JP2020108926A - Injection molding machine and changeover cover for injection molding machine - Google Patents

Abstract

To provide a technique capable of easily connecting a rear end part of an ejector rod and an ejector crosshead and suppressing scattering of a lubricant.SOLUTION: The injection molding machine comprises a mold tightening device including a platen for mounting a mold, and an ejector for ejecting a molded product from the mold, wherein the ejector has an ejector rod, an ejector crosshead, and a drive mechanism, the platen has an opening for performing an operation of connecting the ejector rod and the ejector crosshead, the opening enables access from an outer space of the platen to an inner space of the platen, and enables access in a direction orthogonal to a mold opening/closing direction, and the injection molding machine has a changeover cover for change over between a first state that enables the access from the outer space to the internal space through the opening and a second state that suppresses the scattering of the lubricant from the internal space to the outer space through the opening.SELECTED DRAWING: Figure 6

Description

The present invention relates to an injection molding machine and a switching cover for the injection molding machine.

The injection molding machine described in Patent Document 1 includes a mold clamping device that includes a platen to which a mold is attached, and an ejector device that ejects a molded product from the mold. The ejector device includes an ejector rod, an ejector crosshead to which the ejector rod is connected, and a drive mechanism that advances and retracts the ejector crosshead.

The mold has a fixed mold part fixed to the platen and a movable mold part arranged inside the fixed mold part so as to be movable back and forth. An ejector rod hole is formed in the fixed mold part, and the ejector rod is inserted into the ejector rod hole. When the ejector rod advances and pushes the movable mold part, the molded product is projected from the fixed mold part.

When connecting the movable mold part and the ejector rod, first, the front end part of the ejector rod is inserted into the fixed mold part through the ejector rod hole of the fixed mold part. Next, the screw shaft of the front end portion of the ejector rod is screwed into the screw hole of the movable mold portion. Then, the rear end portion of the ejector rod and the ejector crosshead are connected. If the order is reversed, the work is difficult. This is because if the rear end portion of the ejector rod and the ejector crosshead are connected first, then the fixed mold portion is disassembled and the movable mold portion and the ejector rod are connected.

International Publication No. 2005/068155

The injection molding machine has a connector for connecting the rear end portion of the ejector rod and the ejector crosshead. The connector is arranged in the inner space of the platen. Accessing the inner space of the platen from the rear of the platen to perform the connecting work is troublesome. This is because the drive mechanism is disposed in the rear of the connector in addition to the ejector crosshead, and the drive mechanism prevents access from the rear of the platen to the internal space of the platen.

Therefore, it is conceivable to form an opening in the platen for accessing the inner space of the platen from above or from the side of the platen. However, since the drive mechanism is arranged in the inner space of the platen, the lubricant of the drive mechanism is scattered into the outer space of the platen through the opening of the platen.

One aspect of the present invention provides a technique capable of easily connecting a rear end portion of an ejector rod and an ejector crosshead and suppressing scattering of a lubricant.

An injection molding machine according to one aspect of the present invention,
A mold clamping device including a platen to which a mold is attached,
An ejector device for ejecting a molded product from the mold,
The ejector device has an ejector rod, an ejector crosshead to which the ejector rod is connected, and a drive mechanism for moving the ejector crosshead forward and backward.
The platen has an opening for performing an operation of connecting the ejector rod and the ejector crosshead,
The opening allows access from an external space of the platen to an internal space of the platen, and enables access in a direction orthogonal to a mold opening/closing direction,
A first state that allows the access from the external space to the internal space through the opening, and a second state that suppresses the scattering of the lubricant from the internal space to the external space through the opening. A switching cover for switching between and is provided.

According to the aspect of the present invention, the rear end portion of the ejector rod and the ejector crosshead can be easily connected, and the scattering of the lubricant can be suppressed.

FIG. 1 is a diagram showing a state at the time of completion of mold opening of an injection molding machine according to an embodiment. FIG. 2 is a diagram showing a state when the injection molding machine according to the embodiment is clamped. FIG. 3 is a top view showing the movable platen, the ejector device, and the switching cover according to the embodiment. FIG. 4 is a vertical cross-sectional view showing the movable platen, the ejector device, and the switching cover according to the embodiment, and is a vertical cross-sectional view taken along line IV-IV in FIG. 3. FIG. 5 is a partially enlarged view of FIG. FIG. 6 is a vertical cross-sectional view showing a state of the ejector device shown in FIG. 4 when the ejection is completed. FIG. 7 is a horizontal sectional view showing the movable platen, the ejector device, and the switching cover according to the embodiment, and is a vertical sectional view taken along the line VII-VII of FIG. 4. FIG. 8 is a horizontal cross-sectional view showing the state of the switching cover shown in FIG. 7 during the work of connecting the ejector rod and the ejector crosshead. FIG. 9 is a perspective view showing the switching cover according to the embodiment. FIG. 10 is a view of the movable platen, the ejector device, and the switching cover according to the embodiment when viewed from the rear. FIG. 11 is a vertical sectional view showing a switching cover according to the first modification and a switching cover according to the second modification. FIG. 12 is a vertical sectional view showing a switching cover according to the third modification and a switching cover according to the fourth modification.

Embodiments of the present invention will be described below with reference to the drawings. In each drawing, the same or corresponding components are designated by the same or corresponding reference numerals, and description thereof may be omitted.

(Injection molding machine)
FIG. 1 is a diagram showing a state at the time of completion of mold opening of an injection molding machine according to an embodiment. FIG. 2 is a diagram showing a state when the injection molding machine according to the embodiment is clamped. In this specification, the X-axis direction, the Y-axis direction, and the Z-axis direction are directions perpendicular to each other. The X-axis direction and the Y-axis direction represent the horizontal direction, and the Z-axis direction represents the vertical direction. When the mold clamping device 100 is a horizontal mold, the X-axis direction is the mold opening/closing direction and the Y-axis direction is the width direction of the injection molding machine 10. The negative side in the Y-axis direction is called the operating side, and the positive side in the Y-axis direction is called the non-operating side.

As shown in FIGS. 1 and 2, the injection molding machine 10 includes a mold clamping device 100, an ejector device 200, an injection device 300, a moving device 400, a control device 700, and a frame 900. The frame 900 includes a mold clamping device frame 910 and an injection device frame 920. The mold clamping device frame 910 and the injection device frame 920 are installed on the floor 2 via a leveling adjuster 930, respectively. The control device 700 is disposed in the internal space of the injection device frame 920. Hereinafter, each component of the injection molding machine 10 will be described.

(Clamping device)
In the description of the mold clamping device 100, the moving direction of the movable platen 120 when the mold is closed (for example, the X axis positive direction) is the front, and the moving direction of the movable platen 120 when the mold is opened (the X axis negative direction) is the rear. To do.

The mold clamping device 100 performs mold closing, pressurization, mold clamping, depressurization and mold opening of the mold device 800. The mold device 800 includes a fixed mold 810 and a movable mold 820.

The mold clamping device 100 is, for example, a horizontal mold, and the mold opening/closing direction is horizontal. The mold clamping device 100 includes a fixed platen 110, a movable platen 120, a toggle support 130, a tie bar 140, a toggle mechanism 150, a mold clamping motor 160, a motion converting mechanism 170, and a mold thickness adjusting mechanism 180.

The fixed platen 110 is fixed to the mold clamping device frame 910. A fixed mold 810 is attached to a surface of the fixed platen 110 facing the movable platen 120.

The movable platen 120 is arranged movably in the mold opening/closing direction with respect to the mold clamping device frame 910. A guide 101 that guides the movable platen 120 is laid on the mold clamping device frame 910. A movable mold 820 is attached to a surface of the movable platen 120 facing the fixed platen 110. By moving the movable platen 120 back and forth with respect to the fixed platen 110, the mold device 800 is closed, pressurized, clamped, depressurized, and opened.

The toggle support 130 is arranged at a distance from the fixed platen 110, and is mounted on the mold clamping device frame 910 so as to be movable in the mold opening/closing direction. The toggle support 130 may be movably arranged along a guide laid on the mold clamping device frame 910. The guide of the toggle support 130 may be the same as the guide 101 of the movable platen 120.

In the present embodiment, the fixed platen 110 is fixed to the mold clamping device frame 910, and the toggle support 130 is arranged movably in the mold opening/closing direction with respect to the mold clamping device frame 910. The stationary platen 110 may be fixed to the apparatus frame 910 and movably arranged in the mold opening/closing direction with respect to the mold clamping apparatus frame 910.

The tie bar 140 connects the fixed platen 110 and the toggle support 130 with a space L in the mold opening/closing direction. A plurality of (for example, four) tie bars 140 may be used. The plurality of tie bars 140 are arranged parallel to the mold opening/closing direction and extend according to the mold clamping force. At least one tie bar 140 may be provided with a tie bar strain detector 141 that detects the strain of the tie bar 140. The tie bar distortion detector 141 sends a signal indicating the detection result to the control device 700. The detection result of the tie bar strain detector 141 is used for detecting the mold clamping force and the like.

In this embodiment, the tie bar strain detector 141 is used as the mold clamping force detector that detects the mold clamping force, but the present invention is not limited to this. The mold clamping force detector is not limited to the strain gauge type, but may be a piezoelectric type, a capacitive type, a hydraulic type, an electromagnetic type, or the like, and the mounting position thereof is not limited to the tie bar 140.

The toggle mechanism 150 is arranged between the movable platen 120 and the toggle support 130, and moves the movable platen 120 in the mold opening/closing direction with respect to the toggle support 130. The toggle mechanism 150 includes a crosshead 151, a pair of link groups, and the like. Each of the pair of link groups has a first link 152 and a second link 153 which are flexibly connected by a pin or the like. The first link 152 is swingably attached to the movable platen 120 with a pin or the like. The second link 153 is swingably attached to the toggle support 130 with a pin or the like. The second link 153 is attached to the crosshead 151 via the third link 154. When the crosshead 151 is moved back and forth with respect to the toggle support 130, the first link 152 and the second link 153 bend and stretch, and the movable platen 120 moves back and forth with respect to the toggle support 130.

Note that the configuration of the toggle mechanism 150 is not limited to the configuration shown in FIGS. 1 and 2. For example, although the number of nodes in each link group is five in FIGS. 1 and 2, it may be four, and one end of the third link 154 is coupled to the node between the first link 152 and the second link 153. May be done.

The mold clamping motor 160 is attached to the toggle support 130 and operates the toggle mechanism 150. The mold clamping motor 160 moves the cross head 151 forward and backward with respect to the toggle support 130, thereby bending and extending the first link 152 and the second link 153, and moving the movable platen 120 forward and backward with respect to the toggle support 130. The mold clamping motor 160 is directly connected to the motion converting mechanism 170, but may be connected to the motion converting mechanism 170 via a belt, a pulley, or the like.

The motion conversion mechanism 170 converts the rotational motion of the mold clamping motor 160 into the linear motion of the crosshead 151. The motion conversion mechanism 170 includes a screw shaft and a screw nut screwed onto the screw shaft. A ball or roller may be interposed between the screw shaft and the screw nut.

The mold clamping device 100 performs a mold closing process, a pressure increasing process, a mold clamping process, a depressurizing process, a mold opening process, and the like under the control of the control device 700.

In the mold closing process, the mold clamping motor 160 is driven to move the crosshead 151 forward at the set moving speed to the mold closing completed position, thereby moving the movable platen 120 forward so that the movable mold 820 touches the fixed mold 810. .. The position and movement speed of the crosshead 151 are detected using, for example, the mold clamping motor encoder 161. The mold clamping motor encoder 161 detects the rotation of the mold clamping motor 160 and sends a signal indicating the detection result to the control device 700.

The crosshead position detector that detects the position of the crosshead 151 and the crosshead movement speed detector that detects the movement speed of the crosshead 151 are not limited to the mold clamping motor encoder 161, and general ones are used. it can. The movable platen position detector that detects the position of the movable platen 120 and the movable platen movement speed detector that detects the moving speed of the movable platen 120 are not limited to the mold clamping motor encoder 161, and general ones are used. it can.

In the step-up process, the mold clamping motor 160 is further driven to further advance the crosshead 151 from the mold closing completed position to the mold clamping position to generate a mold clamping force.

In the mold clamping process, the mold clamping motor 160 is driven to maintain the position of the crosshead 151 at the mold clamping position. In the mold clamping process, the mold clamping force generated in the pressurizing process is maintained. In the mold clamping step, a cavity space 801 (see FIG. 2) is formed between the movable mold 820 and the fixed mold 810, and the injection device 300 fills the cavity space 801 with a liquid molding material. A molded product is obtained by solidifying the filled molding material.

The number of cavity spaces 801 may be one or more. In the latter case, a plurality of molded products can be obtained simultaneously. The insert material may be arranged in a part of the cavity space 801, and the molding material may be filled in another part of the cavity space 801. A molded product in which the insert material and the molding material are integrated is obtained.

In the depressurizing step, the mold clamping motor 160 is driven to retract the crosshead 151 from the mold clamping position to the mold opening start position, thereby retracting the movable platen 120 and reducing the mold clamping force. The mold opening start position and the mold closing completion position may be the same position.

In the mold opening process, the mold clamping motor 160 is driven to move the crosshead 151 backward at the set moving speed from the mold opening start position to the mold opening completion position, whereby the movable platen 120 is retracted, and the movable mold 820 is fixed. Separated from the mold 810. Then, the ejector device 200 ejects the molded product from the movable mold 820.

The setting conditions in the mold closing process, the pressurizing process and the mold clamping process are collectively set as a series of setting conditions. For example, the moving speed and position (including the mold closing start position, the moving speed switching position, the mold closing completion position, and the mold closing position) of the crosshead 151 in the mold closing process and the pressurizing process, and the mold clamping force are a series of setting conditions. Is set collectively. The mold closing start position, the moving speed switching position, the mold closing completion position, and the mold clamping position are arranged in this order from the rear side to the front side, and represent the start point and the end point of the section where the moving speed is set. The moving speed is set for each section. The moving speed switching position may be one or plural. The moving speed switching position may not be set. Only one of the mold clamping position and the mold clamping force may be set.

The setting conditions in the depressurizing step and the mold opening step are set in the same manner. For example, the moving speed and position (the mold opening start position, the moving speed switching position, and the mold opening completion position) of the crosshead 151 in the depressurizing process and the mold opening process are collectively set as a series of setting conditions. The mold opening start position, the moving speed switching position, and the mold opening completion position are arranged in this order from the front side to the rear side, and represent the start point and the end point of the section in which the moving speed is set. The moving speed is set for each section. The moving speed switching position may be one or plural. The moving speed switching position may not be set. The mold opening start position and the mold closing completion position may be the same position. Further, the mold opening completion position and the mold closing start position may be the same position.

Note that the moving speed or position of the movable platen 120 may be set instead of the moving speed or position of the crosshead 151. Further, the mold clamping force may be set instead of the position of the crosshead (for example, the mold clamping position) or the position of the movable platen.

By the way, the toggle mechanism 150 amplifies the driving force of the mold clamping motor 160 and transmits it to the movable platen 120. The amplification factor is also called the toggle factor. The toggle magnification changes according to the angle θ formed by the first link 152 and the second link 153 (hereinafter, also referred to as “link angle θ”). The link angle θ is obtained from the position of the crosshead 151. When the link angle θ is 180°, the toggle magnification becomes maximum.

When the thickness of the mold device 800 changes due to the replacement of the mold device 800 or the temperature change of the mold device 800, the mold thickness is adjusted so that a predetermined mold clamping force can be obtained at the time of mold clamping. In the mold thickness adjustment, for example, the interval L between the fixed platen 110 and the toggle support 130 is set so that the link angle θ of the toggle mechanism 150 becomes a predetermined angle at the time of a mold touch in which the movable mold 820 touches the fixed mold 810. Adjust.

The mold clamping device 100 has a mold thickness adjusting mechanism 180. The mold thickness adjusting mechanism 180 adjusts the mold thickness by adjusting the distance L between the fixed platen 110 and the toggle support 130. The timing for adjusting the mold thickness is, for example, from the end of a molding cycle to the start of the next molding cycle. The mold thickness adjusting mechanism 180 is screwed to the screw shaft 181, for example, a screw shaft 181 formed at the rear end of the tie bar 140, a screw nut 182 rotatably and immovably held by the toggle support 130. And a mold thickness adjusting motor 183 for rotating the screw nut 182.

The screw shaft 181 and the screw nut 182 are provided for each tie bar 140. The rotational driving force of the mold thickness adjusting motor 183 may be transmitted to the plurality of screw nuts 182 via the rotational driving force transmission section 185. The plurality of screw nuts 182 can be rotated in synchronization. It is also possible to individually rotate the plurality of screw nuts 182 by changing the transmission path of the rotational driving force transmission portion 185.

The rotational driving force transmission unit 185 is composed of, for example, a gear. In this case, a passive gear is formed on the outer periphery of each screw nut 182, a drive gear is attached to the output shaft of the mold thickness adjusting motor 183, and a plurality of passive gears and an intermediate gear that meshes with the drive gear are provided at the central portion of the toggle support 130. It is rotatably held in. The rotary drive force transmission unit 185 may be configured by a belt, a pulley, or the like instead of the gear.

The operation of the mold thickness adjusting mechanism 180 is controlled by the controller 700. The control device 700 drives the mold thickness adjusting motor 183 to rotate the screw nut 182. As a result, the position of the toggle support 130 with respect to the tie bar 140 is adjusted, and the distance L between the fixed platen 110 and the toggle support 130 is adjusted. Note that a plurality of mold thickness adjusting mechanisms may be used in combination.

The distance L is detected by using the mold thickness adjusting motor encoder 184. The mold thickness adjustment motor encoder 184 detects the rotation amount and the rotation direction of the mold thickness adjustment motor 183, and sends a signal indicating the detection result to the control device 700. The detection result of the mold thickness adjustment motor encoder 184 is used for monitoring and controlling the position and the interval L of the toggle support 130. The toggle support position detector that detects the position of the toggle support 130 and the interval detector that detects the interval L are not limited to the mold thickness adjustment motor encoder 184, and general ones can be used.

The mold clamping device 100 of the present embodiment is a horizontal mold in which the mold opening/closing direction is horizontal, but may be a vertical mold in which the mold opening/closing direction is vertical.

Although the mold clamping device 100 of the present embodiment has the mold clamping motor 160 as a drive source, it may have a hydraulic cylinder instead of the mold clamping motor 160. Further, the mold clamping apparatus 100 may have a linear motor for opening and closing the mold and an electromagnet for clamping the mold.

(Ejector device)
In the description of the ejector device 200, similarly to the description of the mold clamping device 100, the moving direction of the movable platen 120 when the mold is closed (for example, the X-axis positive direction) is the front, and the moving direction of the movable platen 120 when the mold is opened (for example, the mold plate). The X-axis negative direction) will be described as the rear.

The ejector device 200 is attached to the movable platen 120 and moves back and forth together with the movable platen 120. The ejector device 200 has an ejector rod 210 that projects a molded product from the movable mold 820, an ejector crosshead 220 to which the ejector rod 210 is connected, and a drive mechanism 230 that advances and retracts the ejector crosshead 220.

The ejector rod 210 is inserted inside the movable mold 820. The movable die 820 will be described in detail later, but as shown in FIG. 4 and the like, a fixed die portion 830 fixed to the movable platen 120 and a movable die arranged inside the fixed die portion 830 so as to be movable back and forth. And a mold part 840.

The ejector rod 210 is connected to the ejector crosshead 220 and moves back and forth together with the ejector crosshead 220. When the ejector rod 210 moves forward and pushes the movable mold part 840, the molded product is projected from the fixed mold part 830.

The drive mechanism 230 has, for example, as shown in FIG. 5, an ejector motor 240 and a motion conversion mechanism 250 that converts the rotational motion of the ejector motor 240 into the linear motion of the ejector crosshead 220. The motion converting mechanism 250 includes a screw shaft 251 and a screw nut 252 screwed onto the screw shaft 251. Balls or rollers may be interposed between the screw shaft 251 and the screw nut 252.

The ejector device 200 performs the ejection process under the control of the control device 700. In the ejection step, the movable mold part 840 is advanced by advancing the ejector rod 210 from the standby position to the ejection position at the set moving speed, and the molded product is ejected. After that, the ejector motor 240 is driven to retract the ejector rod 210 at the set movement speed, and the movable mold part 840 is retracted to the original standby position.

The position and the moving speed of the ejector rod 210 are detected using, for example, the ejector motor encoder 242. The ejector motor encoder 242 detects the rotation of the ejector motor 240 and sends a signal indicating the detection result to the control device 700. The ejector rod position detector that detects the position of the ejector rod 210 and the ejector rod moving speed detector that detects the moving speed of the ejector rod 210 are not limited to the ejector motor encoder 242, and general ones can be used. ..

(Injection device)
In the description of the injection device 300, unlike the description of the mold clamping device 100 and the ejector device 200, the moving direction of the screw 330 at the time of filling (for example, the negative direction of the X axis) is the front, and the moving direction of the screw 330 at the time of weighing. (For example, the positive direction of the X axis) will be described as the rear.

The injection device 300 is installed on the slide base 301, and the slide base 301 is disposed so as to be movable back and forth with respect to the injection device frame 920. The injection device 300 is arranged so as to be movable back and forth with respect to the mold device 800. The injection device 300 touches the mold device 800 to fill the cavity space 801 in the mold device 800 with the molding material. The injection device 300 includes, for example, a cylinder 310, a nozzle 320, a screw 330, a metering motor 340, an injection motor 350, a pressure detector 360, and the like.

The cylinder 310 heats the molding material supplied inside from the supply port 311. The molding material includes, for example, resin. The molding material is formed into a pellet shape, for example, and is supplied to the supply port 311 in a solid state. The supply port 311 is formed in the rear part of the cylinder 310. A cooler 312 such as a water-cooled cylinder is provided on the outer periphery of the rear portion of the cylinder 310. A heater 313 such as a band heater and a temperature detector 314 are provided on the outer periphery of the cylinder 310 in front of the cooler 312.

The cylinder 310 is divided into a plurality of zones in the axial direction of the cylinder 310 (for example, the X-axis direction). A heater 313 and a temperature detector 314 are provided in each of the plurality of zones. The set temperature is set in each of the plurality of zones, and the controller 700 controls the heater 313 so that the temperature detected by the temperature detector 314 becomes the set temperature.

The nozzle 320 is provided at the front end portion of the cylinder 310 and is pressed against the mold device 800. A heater 313 and a temperature detector 314 are provided on the outer circumference of the nozzle 320. The controller 700 controls the heater 313 so that the temperature detected by the nozzle 320 reaches the set temperature.

The screw 330 is rotatably arranged in the cylinder 310 and is movable back and forth. When the screw 330 is rotated, the molding material is sent forward along the spiral groove of the screw 330. The molding material is gradually melted by the heat from the cylinder 310 while being sent forward. The screw 330 is retracted as the liquid molding material is sent to the front of the screw 330 and accumulated in the front part of the cylinder 310. Then, when the screw 330 is advanced, the liquid molding material accumulated in front of the screw 330 is injected from the nozzle 320 and filled in the mold device 800.

A backflow prevention ring 331 is attached to the front part of the screw 330 as a backflow prevention valve for preventing backflow of the molding material from the front of the screw 330 toward the rear when the screw 330 is pushed forward so as to move back and forth.

When the screw 330 is moved forward, the backflow prevention ring 331 is pushed backward by the pressure of the molding material in front of the screw 330, and is relatively moved to the screw 330 up to the closed position (see FIG. 2) that closes the flow path of the molding material. fall back. This prevents the molding material accumulated in the front of the screw 330 from flowing backward.

On the other hand, the backflow prevention ring 331 is pushed forward by the pressure of the molding material sent forward along the spiral groove of the screw 330 when the screw 330 is rotated, and the open position where the flow path of the molding material is opened. The screw 330 moves forward relative to the screw 330 (see FIG. 1). As a result, the molding material is sent to the front of the screw 330.

The backflow prevention ring 331 may be a co-rotating type that rotates with the screw 330 or a non-co-rotating type that does not rotate with the screw 330.

The injection device 300 may have a drive source that moves the backflow prevention ring 331 forward and backward with respect to the screw 330 between the open position and the closed position.

The metering motor 340 rotates the screw 330. The drive source for rotating the screw 330 is not limited to the metering motor 340, and may be, for example, a hydraulic pump.

The injection motor 350 moves the screw 330 forward and backward. Between the injection motor 350 and the screw 330, a motion conversion mechanism that converts the rotational motion of the injection motor 350 into a linear motion of the screw 330 is provided. The motion conversion mechanism has, for example, a screw shaft and a screw nut screwed onto the screw shaft. A ball, a roller or the like may be provided between the screw shaft and the screw nut. The drive source for moving the screw 330 forward and backward is not limited to the injection motor 350, and may be, for example, a hydraulic cylinder.

The pressure detector 360 detects the force transmitted between the injection motor 350 and the screw 330. The detected force is converted into pressure by the control device 700. The pressure detector 360 is provided in the force transmission path between the injection motor 350 and the screw 330, and detects the force acting on the pressure detector 360.

The pressure detector 360 sends a signal indicating the detection result to the control device 700. The detection result of the pressure detector 360 is used for controlling and monitoring the pressure received by the screw 330 from the molding material, the back pressure on the screw 330, the pressure acting on the molding material from the screw 330, and the like.

The injection device 300 performs a measuring process, a filling process, a pressure holding process, and the like under the control of the control device 700. The filling process and the pressure holding process are collectively referred to as an injection process.

In the measuring step, the measuring motor 340 is driven to rotate the screw 330 at a set rotation speed, and the molding material is sent forward along the spiral groove of the screw 330. Along with this, the molding material is gradually melted. The screw 330 is retracted as the liquid molding material is sent to the front of the screw 330 and accumulated in the front part of the cylinder 310. The rotation speed of the screw 330 is detected using, for example, the metering motor encoder 341. The metering motor encoder 341 detects the rotation of the metering motor 340 and sends a signal indicating the detection result to the control device 700. The screw rotation speed detector for detecting the rotation speed of the screw 330 is not limited to the metering motor encoder 341, and a general one can be used.

In the measuring process, the injection motor 350 may be driven to apply the set back pressure to the screw 330 in order to limit the sudden retreat of the screw 330. The back pressure on the screw 330 is detected by using, for example, the pressure detector 360. The pressure detector 360 sends a signal indicating the detection result to the control device 700. When the screw 330 retracts to the metering completion position and a predetermined amount of molding material is accumulated in front of the screw 330, the metering process is completed.

The position and rotation speed of the screw 330 in the weighing process are collectively set as a series of setting conditions. For example, a measurement start position, a rotation speed switching position, and a measurement completion position are set. These positions are arranged in this order from the front side to the rear side, and represent the start point and the end point of the section in which the rotation speed is set. The rotation speed is set for each section. The rotational speed switching position may be one or plural. The rotation speed switching position may not be set. In addition, back pressure is set for each section.

In the filling process, the injection motor 350 is driven to move the screw 330 forward at a set movement speed, and the liquid molding material accumulated in front of the screw 330 is filled in the cavity space 801 in the mold device 800. The position and the moving speed of the screw 330 are detected by using, for example, the injection motor encoder 351. The injection motor encoder 351 detects the rotation of the injection motor 350 and sends a signal indicating the detection result to the control device 700. When the position of the screw 330 reaches the set position, switching from the filling process to the pressure holding process (so-called V/P switching) is performed. The position where the V/P switching is performed is also called the V/P switching position. The set moving speed of the screw 330 may be changed according to the position of the screw 330, time, and the like.

The position and the moving speed of the screw 330 in the filling process are collectively set as a series of setting conditions. For example, a filling start position (also called “injection start position”), a moving speed switching position and a V/P switching position are set. These positions are arranged in this order from the rear side to the front side, and represent the start point and the end point of the section in which the moving speed is set. The moving speed is set for each section. The moving speed switching position may be one or plural. The moving speed switching position may not be set.

The upper limit of the pressure of the screw 330 is set for each section in which the moving speed of the screw 330 is set. The pressure of the screw 330 is detected by the pressure detector 360. When the detected value of the pressure detector 360 is less than or equal to the set pressure, the screw 330 is advanced at the set moving speed. On the other hand, when the detected value of the pressure detector 360 exceeds the set pressure, the screw 330 moves at a moving speed slower than the set moving speed so that the detected value of the pressure detector 360 becomes equal to or lower than the set pressure for the purpose of die protection. Be advanced in.

In addition, in the filling process, after the position of the screw 330 reaches the V/P switching position, the screw 330 may be temporarily stopped at the V/P switching position, and then the V/P switching may be performed. Immediately before the V/P switching, instead of stopping the screw 330, a slight speed forward movement or a slight speed backward movement of the screw 330 may be performed. Further, the screw position detector that detects the position of the screw 330 and the screw movement speed detector that detects the movement speed of the screw 330 are not limited to the injection motor encoder 351, and general ones can be used.

In the pressure-holding step, the injection motor 350 is driven to push the screw 330 forward, the pressure of the molding material at the front end portion of the screw 330 (hereinafter, also referred to as “holding pressure”) is kept at a set pressure, and the pressure is kept in the cylinder 310. The remaining molding material is pushed toward the mold device 800. A shortage of molding material due to cooling shrinkage in the mold device 800 can be replenished. The holding pressure is detected using, for example, the pressure detector 360. The pressure detector 360 sends a signal indicating the detection result to the control device 700. The set value of the holding pressure may be changed according to the elapsed time from the start of the pressure holding process. A plurality of holding pressures and holding times for holding the holding pressures in the pressure holding step may be set, respectively, and may be collectively set as a series of setting conditions.

In the pressure holding step, the molding material in the cavity space 801 in the mold apparatus 800 is gradually cooled, and at the completion of the pressure holding step, the inlet of the cavity space 801 is closed with the solidified molding material. This state is called a gate seal and prevents backflow of the molding material from the cavity space 801. After the pressure holding step, the cooling step is started. In the cooling process, the molding material in the cavity space 801 is solidified. A metering step may be performed during the cooling step in order to reduce the molding cycle time.

The injection device 300 of the present embodiment is an in-line screw system, but may be a pre-plastic system or the like. The pre-plastic type injection device supplies the molding material melted in the plasticizing cylinder to the injection cylinder, and injects the molding material from the injection cylinder into the mold device. In the plasticizing cylinder, a screw is rotatably and immovably arranged, or a screw is rotatably and movably arranged. On the other hand, a plunger is arranged in the injection cylinder so as to be movable back and forth.

Further, the injection device 300 of the present embodiment is a horizontal type in which the axial direction of the cylinder 310 is horizontal, but it may be a vertical type in which the axial direction of the cylinder 310 is vertical. The mold clamping device combined with the vertical injection device 300 may be a vertical mold or a horizontal mold. Similarly, the mold clamping device combined with the horizontal injection device 300 may be a horizontal type or a vertical type.

(Moving device)
In the description of the moving device 400, similarly to the description of the injection device 300, the moving direction of the screw 330 during filling (for example, the negative direction of the X axis) is the front, and the moving direction of the screw 330 during weighing (for example, the positive direction of the X axis). Will be described as backward.

The moving device 400 moves the injection device 300 back and forth with respect to the mold device 800. Further, the moving device 400 presses the nozzle 320 against the mold device 800 to generate a nozzle touch pressure. The moving device 400 includes a hydraulic pump 410, a motor 420 as a drive source, a hydraulic cylinder 430 as a hydraulic actuator, and the like. When the motor 420 is driven, the hydraulic pump 410 supplies hydraulic pressure to the hydraulic cylinder 430, and the hydraulic cylinder 430 moves the injection device 300 forward and backward by the hydraulic pressure.

Although the moving device 400 includes the hydraulic cylinder 430 in the present embodiment, the present invention is not limited to this. For example, instead of the hydraulic cylinder 430, an electric motor and a motion conversion mechanism that converts the rotational motion of the electric motor into the linear motion of the injection device 300 may be used.

(Control device)
The control device 700 is composed of, for example, a computer, and has a CPU (Central Processing Unit) 701, a storage medium 702 such as a memory, an input interface 703, and an output interface 704, as shown in FIGS. The control device 700 performs various controls by causing the CPU 701 to execute the programs stored in the storage medium 702. Further, in the control device 700, the input interface 703 receives a signal from the outside, and the output interface 704 transmits the signal to the outside.

The control device 700 repeatedly performs a measuring process, a mold closing process, a pressurizing process, a mold clamping process, a filling process, a pressure holding process, a cooling process, a depressurizing process, a mold opening process, an ejecting process, and the like to form a molded product. Repeatedly manufactured. A series of operations for obtaining a molded product, for example, an operation from the start of a weighing process to the start of the next weighing process is also referred to as "shot" or "molding cycle". The time required for one shot is also referred to as "molding cycle time" or "cycle time".

One molding cycle has, for example, a measuring step, a mold closing step, a pressurizing step, a mold clamping step, a filling step, a pressure holding step, a cooling step, a depressurizing step, a mold opening step, and an ejecting step in this order. The order here is the order of starting each process. The filling step, the pressure holding step, and the cooling step are performed during the mold clamping step. The start of the mold clamping process may coincide with the start of the filling process. The end of the depressurization process coincides with the start of the mold opening process.

Note that a plurality of steps may be performed at the same time for the purpose of shortening the molding cycle time. For example, the measuring step may be performed during the cooling step of the previous molding cycle, or may be performed during the mold clamping step. In this case, the mold closing step may be performed at the beginning of the molding cycle. Further, the filling process may be started during the mold closing process. Further, the ejecting step may be started during the mold opening step. When the opening/closing valve that opens/closes the flow path of the nozzle 320 is provided, the mold opening process may be started during the metering process. This is because, even if the mold opening process is started during the measuring process, the molding material does not leak from the nozzle 320 if the opening/closing valve closes the flow path of the nozzle 320.

It should be noted that one molding cycle has steps other than the measuring step, the mold closing step, the pressurizing step, the mold clamping step, the filling step, the pressure holding step, the cooling step, the depressurizing step, the mold opening step, and the ejecting step. May be.

For example, after the pressure holding process is completed and before the start of the measuring process, a pre-measurement suckback process of retracting the screw 330 to a preset measuring start position may be performed. It is possible to reduce the pressure of the molding material accumulated in front of the screw 330 before the start of the measuring process, and prevent the screw 330 from suddenly retracting at the start of the measuring process.

Further, after the measurement process is completed and before the start of the filling process, a post-measurement suckback process of retracting the screw 330 to a preset filling start position (also referred to as “injection start position”) may be performed. The pressure of the molding material accumulated in front of the screw 330 before the start of the filling process can be reduced, and the leakage of the molding material from the nozzle 320 before the start of the filling process can be prevented.

The control device 700 is connected to the operation device 750 and the display device 760. The operation device 750 receives an input operation by the user and outputs a signal according to the input operation to the control device 700. The display device 760 displays a display screen according to an input operation on the operation device 750 under the control of the control device 700.

The display screen is used for setting the injection molding machine 10 and the like. A plurality of display screens are prepared and can be switched and displayed or overlapped. The user operates the operation device 750 while looking at the display screen displayed on the display device 760 to set the injection molding machine 10 (including input of set values).

The operation device 750 and the display device 760 may be configured by, for example, a touch panel and integrated. Although the operation device 750 and the display device 760 of this embodiment are integrated, they may be provided independently. Further, a plurality of operation devices 750 may be provided. The operation device 750 and the display device 760 are arranged on the Y axis direction negative side of the mold clamping device 100 (more specifically, the fixed platen 110). The negative side in the Y-axis direction is called the operating side, and the positive side in the Y-axis direction is called the non-operating side.

(Movable platen, ejector device and switching cover)
FIG. 3 is a top view showing the movable platen, the ejector device, and the switching cover according to the embodiment. FIG. 4 is a vertical cross-sectional view showing the movable platen, the ejector device, and the switching cover according to the embodiment, and is a vertical cross-sectional view taken along line IV-IV in FIG. 3. Note that FIG. 4 shows a state at the time of starting the ejection of the ejector device. FIG. 5 is a partially enlarged view of FIG. FIG. 6 is a vertical cross-sectional view showing a state of the ejector device shown in FIG. 4 when the ejection is completed. FIG. 7 is a horizontal sectional view showing the movable platen, the ejector device, and the switching cover according to the embodiment, and is a vertical sectional view taken along the line VII-VII of FIG. 4. FIG. 8 is a horizontal cross-sectional view showing the state of the switching cover shown in FIG. 7 during the work of connecting the ejector rod and the ejector crosshead. FIG. 9 is a perspective view showing the switching cover according to the embodiment. FIG. 10 is a view of the movable platen, the ejector device, and the switching cover according to the embodiment when viewed from the rear.

As shown in FIG. 4 and the like, the movable platen 120 includes a movable mold mounting portion 510 to which the movable mold 820 is mounted, and a first link mounting portion 520 to which the first link 152 of the toggle mechanism 150 is swingably mounted. Have. The movable platen 120 has a load transmission part 530 that transmits a load (for example, a mold clamping force and its reaction force) between the first link mounting part 520 and the movable mold mounting part 510. Further, the movable platen 120 has a pair of support leg portions 540 that support the load transmission portion 530, as shown in FIG.

The movable mold mounting portion 510 is formed in a rectangular shape when viewed in the mold opening/closing direction. As shown in FIG. 10, cutouts 511 are formed at the four corners of the movable mold mounting portion 510 in order to avoid interference with the tie bars 140 when viewed in the mold opening/closing direction. Instead of the notch 511, a through hole may be formed and the tie bar 140 may be arranged in the through hole.

As shown in FIG. 4, the movable mold mounting portion 510 is formed with an ejector rod hole 512 that penetrates the movable mold mounting portion 510 in the mold opening/closing direction. The ejector rod hole 512 is formed in the central portion of the movable mold mounting portion 510 when viewed in the mold opening/closing direction. The ejector rod hole 512 is formed from the front end surface of the movable mold mounting portion 510 to the internal space of the load transmitting portion 530. The ejector rod 210 is arranged in the ejector rod hole 512 so as to be movable back and forth.

A pair of first link attachment portions 520 are provided at intervals in the Z-axis direction. Each of the pair of first link attachment portions 520 includes a plurality of link attachment plates 521 arranged at intervals in the Y-axis direction. First link pin holes 522 that penetrate the link mounting plates 521 in the Y-axis direction are formed in the plurality of link mounting plates 521. The first link pin is inserted into the first link pin hole 522. The first link pin swingably connects the first link 152 to the first link attachment portion 520.

As shown in FIG. 10, the load transmitting portion 530 is formed in a rectangular frame shape when viewed in the mold opening/closing direction. As shown in FIG. 4 and the like, the upper surface of the load transmitting portion 530 has an inclined portion 531 that inclines downward as it goes forward. Similarly, the lower surface of the load transmission part 530 has an inclined part 532 that inclines upward as it goes forward. By forming the pair of upper and lower inclined portions 531 and 532, the mold clamping force transmitted from the pair of upper and lower first link attaching portions 520 to the load transmitting portion 530 is arranged in the vertical center portion of the load transmitting portion 530. It can be intensively transmitted to the movable mold 820.

As shown in FIG. 10, a pair of support leg portions 540 are provided with the load transmission portion 530 sandwiched in the Y-axis direction. The pair of support leg portions 540 respectively support the Z axis direction central portion of the Y axis direction end surface of the load transmission portion 530, and support the load transmission portion 530 by floating from the mold clamping device frame 910. The heat from the movable mold 820 is transmitted to the mold clamping device frame 910 via the movable mold attachment portion 510, the load transmission portion 530 and the support leg portion 540. Heat transfer from the load transfer part 530 to the mold clamping device frame 910 can be suppressed, and the temperature distribution of the load transfer part 530 can be vertically symmetrical. Therefore, the inclination of the load transmission unit 530 can be suppressed.

The support leg portion 540 has, for example, a vertical portion 541 and an inclined portion 542 that extends obliquely upward from the upper end portion of the vertical portion 541. The vertical portion 541 is composed of a vertical column, and is fixed to the slide base 102 at the lower end portion. The slide base 102 moves back and forth along the guide 101. The inclined portion 542 extends from the upper end portion of the vertical portion 541 to the Z-axis direction central portion of the Y-axis direction end surface of the load transmission portion 530.

The movable mold 820 is attached to the movable platen 120 and moves back and forth together with the movable platen 120. The movable mold 820 has a fixed mold part 830 fixed to the movable platen 120, and a movable mold part 840 arranged inside the fixed mold part 830 so as to be movable back and forth.

The fixed mold part 830 is fixed to the movable mounting plate 831 via the movable mounting plate 831 mounted on the movable platen 120, a spacer block 835 forming a space 834 in front of the movable mounting plate 831, and the spacer block 835. And a movable mold plate 836.

The movable mounting plate 831 is formed with an ejector rod hole 832 that penetrates the movable mounting plate 831 in the mold opening/closing direction. The ejector rod 210 is arranged in the ejector rod hole 832 so as to be movable back and forth.

The spacer block 835 is formed in a rectangular frame shape when viewed in the mold opening/closing direction. The spacer block 835 forms a space 834 between the movable mounting plate 831 and the movable mold plate 836. An ejector plate 841 is arranged in this space 834 so as to be able to move back and forth.

The movable mold plate 836 forms a cavity space 801 together with the fixed mold 810. The molded product 20 solidified in the cavity space 801 retracts together with the movable mold plate 836 when the mold is opened, and then is projected from the movable mold plate 836.

The fixed mold part 830 includes a guide pin 839 that guides the movable mold part 840. The axial direction of the guide pin 839 is the X-axis direction. The movable mold part 840 moves back and forth along the guide pin 839.

The movable mold part 840 is arranged in the fixed mold part 830 so as to be movable back and forth. The movable mold part 840 includes, for example, a plate-shaped ejector plate 841 that is perpendicular to the mold opening/closing direction, and a rod-shaped ejector pin 844 that extends forward from the ejector plate 841.

The ejector plate 841 is arranged to be movable back and forth in a space 834 between the movable mounting plate 831 and the movable mold plate 836. The ejector plate 841 moves back and forth along the guide pin 839. The ejector plate 841 is biased by the return spring 845 in a direction away from the movable mold plate 836.

The return spring 845 may be omitted when connecting the ejector plate 841 and the ejector rod 210 as described later. This is because the ejector plate 841 moves back and forth together with the ejector rod 210.

The ejector pin 844 is arranged so as to be movable back and forth in an ejector pin hole that penetrates the movable mold plate 836 in the mold opening/closing direction. The ejector pin 844 moves back and forth together with the ejector plate 841. When the ejector plate 841 is in the retracted limit position, the front end surface of the ejector pin 844 is flush with the front end surface of the movable die plate 836. The front end surface of the ejector pin 844 contacts the molded product 20.

The ejector device 200 has an ejector rod 210 that moves back and forth in the mold opening/closing direction. The ejector rod 210 is disposed in the ejector rod hole 832 of the fixed mold part 830 so as to be able to move back and forth. When the ejector rod 210 advances and pushes the movable mold part 840 forward, the movable mold part 840 advances and the molded product 20 is projected from the fixed mold part 830. When the movable mold part 840 and the ejector rod 210 are connected, the ejector rod 210 retracts with the movable mold part 840 in front when retracting.

If the movable mold part 840 and the ejector rod 210 are not connected, a spring that biases the movable mold part 840 backward is provided. When the ejector rod 210 moves forward, it moves the movable mold part 840 forward against the elastic restoring force of the spring. When the ejector rod 210 retracts, the movable mold part 840 retracts due to the elastic restoring force of the spring. If the spring fails, the movable mold part 840 does not retract when the ejector rod 210 retracts, so a sensor for monitoring the position of the movable mold part 840 is provided.

According to this embodiment, since the movable mold part 840 and the ejector rod 210 are connected, a spring for urging the movable mold part 840 rearward is unnecessary. Therefore, the movable mold part 840 can be moved back and forth without being affected by the fluctuation of the elastic restoring force of the spring due to the expansion and contraction of the spring. Further, if the position of the ejector rod 210 is monitored, the position of the movable mold part 840 can also be monitored. Therefore, not only the spring is unnecessary, but also the sensor for monitoring the position of the movable mold part 840 is unnecessary.

The ejector device 200 includes an ejector crosshead 220 to which the ejector rod 210 is connected, and a drive mechanism 230 that moves the ejector crosshead 220. The ejector device 200 has a mounting board 260 for mounting the drive mechanism 230 to the movable platen 120. Further, the ejector device 200 has a plurality of guide rods 270 extending forward from the mounting board 260.

The ejector crosshead 220 moves back and forth along the plurality of guide rods 270. The plurality of guide rods 270 also have a role of inhibiting rotation of the ejector crosshead 220. A stopper 271 is provided at the front end of the guide rod 270. The stopper 271 prevents the ejector crosshead 220 from coming off the guide rod 270.

The drive mechanism 230 includes, for example, an ejector motor 240 and a motion conversion mechanism 250 that converts the rotational motion of the ejector motor 240 into the linear motion of the ejector crosshead 220. As shown in FIG. 5, the motion converting mechanism 250 includes a screw shaft 251 and a screw nut 252 screwed onto the screw shaft 251. Balls or rollers may be interposed between the screw shaft 251 and the screw nut 252. The screw shaft 251 of the motion converting mechanism 250 and the output shaft 241 of the ejector motor 240 are arranged on the same straight line.

The motion conversion mechanism 250 further includes a spline nut 253 fixed to the output shaft 241 of the ejector motor 240, and a spline shaft 254 splined to the spline nut 253. The output shaft 241 of the ejector motor 240 is formed in a tubular shape. A spline nut 253 and a spline shaft 254 are inserted inside the output shaft 241. The output shaft 241 of the ejector motor 240 and the spline shaft 254 of the motion conversion mechanism 250 can be overlapped with each other when viewed in a direction orthogonal to the X-axis direction, and the dimension of the drive mechanism 230 in the X-axis direction can be shortened.

The motion converting mechanism 250 further includes a rotating shaft 255 that rotates together with the screw shaft 251, and a bearing 256 that rotatably supports the rotating shaft 255. The bearing 256 has an inner ring that rotates together with the rotating shaft 255 and an outer ring that is held by the ejector crosshead 220. The bearing 256 prevents the rotation driving force from being transmitted from the rotating shaft 255 to the ejector crosshead 220.

The spline shaft 254, the screw shaft 251, and the rotating shaft 255 are arranged on the same straight line and integrated. The spline shaft 254, the screw shaft 251, and the rotating shaft 255 are arranged in this order from rear to front.

When the output shaft 241 of the ejector motor 240 is rotated, the spline nut 253, the spline shaft 254, and the screw shaft 251 rotate together with the output shaft 241. Since the screw nut 252 is fixed to the mounting board 260, it does not rotate together with the screw shaft 251. Therefore, the screw shaft 251 moves forward and backward while rotating. The spline shaft 254 and the spline nut 253 are spline-coupled so that the screw shaft 251 and the spline shaft 254 can move forward and backward while rotating. As the screw shaft 251 rotates, the ejector crosshead 220 moves back and forth.

The screw shaft 251 of the motion converting mechanism 250 and the output shaft 241 of the ejector motor 240 are arranged on the same straight line in the present embodiment, but they may not be arranged on the same straight line. In the latter case, the rotational movement of the ejector motor 240 is transmitted to the movement conversion mechanism 250 via, for example, a pulley and a timing belt.

The mounting board 260 is mounted on the load transmission portion 530 of the movable platen 120, as shown in FIG. The load transmission part 530 is formed in a square frame shape when viewed in the mold opening/closing direction, for example. A step surface 533 is formed in a ring shape on the inner peripheral surface of the load transmitting portion 530. The mounting board 260 is fixed to the step surface 533.

As shown in FIG. 10 and the like, the mounting board 260 has a rectangular mounting board main body 261 as viewed in the mold opening/closing direction, and four mounting arms 262 radially protruding from the mounting board main body 261 in the mold opening/closing direction. .. The respective tip portions of the four mounting arms 262 are fixed to the step surface 533 on the inner peripheral surface of the load transmitting portion 530 with bolts or the like. Since the space 534 can be formed between the mounting board body 261 and the inner peripheral surface of the load transmitting portion 530, the mounting board 260 can be made smaller and lighter.

As shown in FIG. 4, the mounting board 260 is formed with a through hole 263 that penetrates the mounting board 260 in the mold opening/closing direction. The through hole 263 is formed in the central portion of the mounting board body 261 as viewed in the mold opening/closing direction. The drive mechanism 230 is arranged in the through hole 263 of the mounting board 260. More specifically, the screw nut 252 of the drive mechanism 230 is arranged in the through hole 263 of the mounting board 260.

Next, the work of connecting the movable mold part 840 and the ejector rod 210 will be described. First, before fixing the fixed mold part 830 to the movable platen 120, the front end part of the ejector rod 210 is inserted into the fixed mold part 830 through the ejector rod hole 832 of the fixed mold part 830. Next, the screw shaft 211 at the front end of the ejector rod 210 is screwed into the screw hole 842 of the movable mold part 840. The screw hole 842 is formed, for example, on the rear end surface of the ejector plate 841.

In the present embodiment, the screw shaft 211 is formed at the front end portion of the ejector rod 210 and the screw hole 842 is formed at the rear end surface of the ejector plate 841, but the screw shaft 211 and the screw hole 842 may be arranged in reverse. That is, the screw hole 842 may be formed in the front end surface of the ejector rod 210, and the screw shaft 211 may be formed in the rear end surface of the ejector plate 841.

Thereafter, the fixed mold part 830 is fixed to the movable platen 120, and subsequently, the rear end part of the ejector rod 210 and the ejector cross head 220 are connected by the connecting tool 600. The connector 600, for example, as shown in FIG. 5, connects the flange at the rear end of the ejector rod 210 and the flange at the front end of the ejector crosshead 220 by butting them. The connector 600 has a first divided portion 601 that presses the rear end flange of the ejector rod 210 from the front, and a second divided portion 602 that presses the front end flange of the ejector crosshead 220 from the rear. The first divided portion 601 and the second divided portion 602 are connected by a bolt or the like. The connector 600 may be a general one.

If the order of the connection between the front end of the ejector rod 210 and the movable mold part 840 and the connection between the rear end of the ejector rod 210 and the ejector crosshead 220 is reversed, the work is difficult. If the rear end of the ejector rod 210 and the ejector crosshead 220 are connected to each other, then the fixed mold part 830 is disassembled to connect the movable mold part 840 to the front end of the ejector rod 210. Because

The connector 600 is arranged in the internal space 121 of the movable platen 120, as shown in FIG. 4. The internal space 121 of the movable platen 120 is a space in which the ejector device 200 is arranged. Accessing the connector 600 from the rear of the movable platen 120 is cumbersome. Behind the connector 600, not only the ejector crosshead 220 but also the drive mechanism 230 is arranged. The drive mechanism 230 blocks access to the connector 600 from the rear of the movable platen 120.

The movable platen 120 has an opening 123 for performing a work of connecting the ejector rod 210 and the ejector crosshead 220. Hereinafter, the work of connecting the ejector rod 210 and the ejector crosshead 220 will be simply referred to as the connecting work. The opening 123 is an access from the external space 122 of the movable platen 120 to the internal space 121 of the movable platen 120, and allows access in a direction orthogonal to the mold opening/closing direction (for example, the vertical direction). The connection work is performed by a human or a robot. The outer space 122 of the movable platen 120 is a space on the opposite side of the inner space 121 with the opening 123 as a reference.

The opening 123 for connecting work is formed on the upper surface of the movable platen 120, more specifically, on the upper surface of the load transmission portion 530 of the movable platen 120, as shown in FIG. In order to make the rigidity of the movable platen 120 vertically symmetrical, the opening 125 is also formed on the lower surface of the movable platen 120, more specifically, the lower surface of the load transmission portion 530 of the movable platen 120. The lower opening 125 is not for connecting work in the present embodiment, but may be for connecting work.

The worker or the work robot accesses the internal space 121 of the movable platen 120 from the external space 122 of the movable platen 120 through the opening 123 of the movable platen 120 to perform the connecting work. Then, the worker or the work robot exits from the internal space 121 of the movable platen 120 to the external space of the movable platen 120.

The worker or the work robot can perform the uncoupling work in the same manner as the coupling work. The connection releasing operation is an operation of releasing the connection between the ejector rod 210 and the ejector crosshead 220.

The worker or the work robot accesses the internal space 121 of the movable platen 120 from the external space 122 of the movable platen 120 through the opening 123 of the movable platen 120 to perform the disconnection work. Then, the worker or the work robot exits from the internal space 121 of the movable platen 120 to the external space 122 of the movable platen 120.

In addition, although the opening 123 for connection work of the present embodiment is formed on the upper surface of the movable platen 120, the present invention is not limited to this. The opening 123 for connecting work includes an upper surface (end surface on the positive side in the Z-axis direction), a lower surface (end surface on the negative side in the Z-axis direction), a lateral side surface on the opposite side (end surface on the positive side in the Y-axis direction), and an operating side. It may be formed on at least one of the lateral side faces (the end face on the negative side in the Y-axis direction).

That is, the opening 123 for connecting work may be any one for accessing the internal space 121 of the movable platen 120 from the direction orthogonal to the mold opening/closing direction. In the present embodiment, the working opening 123 is formed on the upper surface of the load transmitting portion 530, as shown in FIG. 3, on the side surface on the opposite side of the load transmitting portion 530 and on the operating side of the load transmitting portion 530. This is because the lateral side surface is closed by the support leg portion 540.

By the way, in the internal space 121 of the movable platen 120, not only the connector 600 but also the drive mechanism 230 is arranged. The drive mechanism 230 is supplied with a lubricant such as grease from the lubricant supply unit 610.

The lubricant supply unit 610 is attached to the upper surface of the movable platen 120, as shown in FIG. More specifically, the lubricant supply unit 610 is attached to the upper surface of the load transmission unit 530 of the movable platen 120. A lubricant passage 611 that extends vertically downward to the inner peripheral surface of the movable platen 120 is formed on the upper surface of the movable platen 120. A lubricant passage 612 is formed on an extension of the lubricant passage 611. The lubricant passage 612 extends vertically downward from the upper surface of the mounting board 260 to the through hole 263 of the mounting board 260.

The lubricant flows down through the lubricant passage 611 of the movable platen 120 and the lubricant passage 612 of the mounting board 260, and is supplied to the motion conversion mechanism 250. The lubricant is first supplied to the screw nut 252 and then to the screw shaft 251. Then, the lubricant spreads forward and backward along the screw shaft 251 and is also supplied to the spline shaft 254 and the bearing 256.

As shown in FIG. 6, the lubricant is scattered from the rotating screw shaft 251 by the centrifugal force between the mounting board 260 and the ejector crosshead 220. More specifically, the lubricant disperses from the rotating screw shaft 251 by centrifugal force between the screw nut 252 and the ejector crosshead 220, as shown in FIG. The scattered lubricant is directed to the opening 123 on the upper side of the movable platen 120, as shown by the arrow in FIG.

The injection molding machine 10 includes a switching cover 620 to stop the lubricant from scattering toward the upper opening 123. The scattered lubricant also goes to the lower opening 125. The lubricant that has passed through the lower opening 125 is received by the oil pan. The oil pan is placed on the upper surface of the frame 900, for example.

The switching cover 620 is in a first state in which access from the external space 122 to the internal space 121 via the opening 123 of the movable platen 120 is permitted, and from the internal space 121 via the opening 123 of the movable platen 120 to the external space 122. The state is switched to the second state in which the scattering of the lubricant to the inside is suppressed. When the switching cover 620 is in the second state, compared to the first state, the switching cover 620 suppresses the lubricant from scattering from the internal space 121 to the external space 122 through the opening 123.

When the switching cover 620 is in the second state, the opening degree of the opening 123 is smaller than when the switching cover 620 is in the first state when viewed from the access direction (for example, the vertical direction) during the connecting work. The small opening degree of the opening 123 means that the area of the opening 123 covered by the switching cover 620 is large. As the opening degree of the opening 123 is smaller, the scattering of the lubricant from the inner space 121 to the outer space 122 through the opening 123 can be suppressed.

The switching cover 620 is, for example, a slide cover that moves in parallel. The switching cover 620 slides between the position shown in FIG. 7 and the position shown in FIG. The sliding direction is, for example, the X-axis direction.

At the position shown in FIG. 8, the switching cover 620 is in the first state that allows the connecting work from the opening 123 of the movable platen 120. The connecting operation is an operation of connecting the ejector rod 210 and the ejector crosshead 220 as described above.

As shown in FIG. 8, while the connecting work is performed, the ejector crosshead 220 stops at the backward limit position and the ejector plate 841 stops at the backward limit position. As shown in FIG. 4, when the ejector plate 841 stops at the retracted limit position, the front end surface of the ejector pin 844 is flush with the front end surface of the movable die plate 836.

As shown in FIG. 8, at least the connector 600 is inside the contour line 124 of the opening 123 of the movable platen 120 when viewed from the access direction (for example, from above) of the worker or the work robot while the connection work is performed. A part is placed. This allows the connecting work. In the present embodiment, the entire connecting tool 600 is arranged inside the contour line 124 of the opening 123, so the connecting work is easier.

At the position shown in FIG. 7, switching cover 620 is in the second state in which lubricant is prevented from splashing from internal space 121 to external space 122 through opening 123 of movable platen 120. As shown in FIG. 6, the lubricant is scattered from the rotating screw shaft 251 by the centrifugal force between the mounting board 260 and the ejector crosshead 220.

The distance between the mounting board 260 and the ejector cross head 220 is widest when the ejector cross head 220 is moved most forward and the ejector rod 210 reaches the protruding position, as shown in FIG. At this time, the screw shaft 251 and the opening 123 for connecting work of the movable platen 120 overlap each other when viewed from the access direction (for example, above) during connecting work.

When the distance between the mounting plate 260 and the ejector crosshead 220 is widest, at least a part of the portion of the screw shaft 251 that overlaps the opening 123 is covered with the switching cover 620 when viewed from the access direction (for example, from above) at the time of connection work. Be seen. Accordingly, the scattering of the lubricant from the internal space 121 to the external space 122 via the opening 123 of the movable platen 120 is suppressed.

When the distance between the mounting plate 260 and the ejector crosshead 220 is widest, the entire portion of the screw shaft 251 that overlaps the opening 123 is covered with the switching cover 620 when viewed from the access direction (for example, from above) during the connecting work. Good. Thereby, the scattering of the lubricant from the internal space 121 to the external space 122 via the opening 123 of the movable platen 120 can be further suppressed.

It should be noted that the switching cover 620 does not have to overlap the entire opening 123 for connecting work at the position shown in FIG. 7 when viewed from the access direction (for example, above) during connecting work. It suffices that the opening degree of the opening 123 of the movable platen 120 is reduced by sliding the switching cover 620 from the position shown in FIG. 8 to the position shown in FIG. 7.

As shown in FIGS. 7 and 8, the switching cover 620 has, for example, a flat plate portion 621 and a guide hole portion 624 formed in the flat plate portion 621. The flat plate portion 621 is fixed to the upper surface of the mounting board 260 with bolts 625. The bolt 625 passes through the guide hole portion 624 and is screwed into the bolt hole on the upper surface of the mounting board 260.

The guide hole portion 624 is a long hole extending in the sliding direction of the switching cover 620 (for example, the X axis direction). A plurality of guide hole portions 624 are provided at intervals in a direction (eg, Y-axis direction) orthogonal to the sliding direction of the switching cover 620. A bolt 625 is arranged in each of the plurality of guide hole portions 624.

By loosening the bolt 625, the switching cover 620 can be slid while the bolt 625 is screwed into the bolt hole. After the switching cover 620 is slid, the switching cover 620 is fixed to the upper surface of the mounting plate 260 by tightening the bolts 625. The operator tightens the bolt 625 with a tool such as a spanner or a wrench in order to suppress the vibration of the switching cover 620.

A knob may be formed on the head of the bolt 625. That is, the bolt 625 may be a so-called butterfly bolt. The operator can operate the bolt 625 without using a tool. A non-slip groove may be formed on the head of the bolt 625.

As shown in FIG. 9, the switching cover 620 has a cutout portion 626 formed in the flat plate portion 621. The flat plate portion 621 includes a first rectangular plate portion 622 that is rectangular in a top view and a second rectangular plate portion 623 that is rectangular in a top view. The second rectangular plate portion 623 is arranged behind the first rectangular plate portion 622 (on the negative side in the X-axis direction). The dimension of the second rectangular plate portion 623 in the Y-axis direction is shorter than the dimension of the first rectangular plate portion 622 in the Y-axis direction.

The cutout portions 626 are arranged on both sides of the second rectangular plate portion 623 in the Y axis direction. The mounting arm 262 of the mounting board 260 is arranged in the notch 626. Interference between the mounting arm 262 of the mounting board 260 and the switching cover 620 can be avoided, and the sliding distance of the switching cover 620 can be increased.

As shown in FIG. 7, when the switching cover 620 suppresses the scattering of the lubricant, the opening 123 and the notch 626 do not overlap with each other when viewed from the access direction (for example, from above) during the connecting work. Therefore, the lubricant is not scattered from the cutout 626 to the opening 123.

The switching cover 620 has a plate-shaped stopper portion 627 perpendicular to the flat plate portion 621. The stopper portion 627 stops the switching cover 620 by coming into contact with the rear surface of the mounting board body 261 when the switching cover 620 is advanced from the position shown in FIG. 8 to the position shown in FIG. 7. The stop position of the switching cover 620 can be defined.

The stopper portion 627 may be formed with a through hole that penetrates the stopper portion 627 in the front-rear direction. A bolt is arranged in this through hole. The bolt passes through the through hole of the stopper portion 627 and is screwed into the bolt hole on the rear surface of the mounting board body 261. In this case, a guide pin may be arranged in the guide hole portion 624 instead of the bolt 625. The arrangement of the guide pin and the guide hole portion 624 may be reversed. That is, the guide pin may be provided on the lower surface of the switching cover 620 and the guide hole portion 624 may be formed on the upper surface of the mounting board body 261.

The switching cover 620 has a lubricant passage portion 628 formed on the flat plate portion 621. The lubricant passage portion 628 is a hole for passing the lubricant that flows down from the lubricant passage 611 of the movable platen 120 toward the lubricant passage 612 of the mounting board 260.

As described above, according to the present embodiment, when the switching cover 620 is in the first state, from the external space 122 to the internal space 121 via the opening 123 of the movable platen 120 in the direction orthogonal to the mold opening/closing direction. Since it is accessible, connection work can be performed. Further, when the switching cover 620 is in the second state, it is possible to suppress the scattering of the lubricant from the internal space 121 to the external space 122 via the opening 123. Since the state of the switching cover 620 is switched between the first state and the second state, the connecting work can be easily performed and the scattering of the lubricant can be suppressed.

By the way, the switching cover 620 of the present embodiment is arranged in the internal space 121 of the movable platen 120, as shown in FIG. The switching cover 620 is arranged between the drive mechanism 230 and the opening 123. The switching cover 620 is attached to the ejector device 200, for example. When the switching cover 620 is disposed in the internal space 121 of the movable platen 120, it may be attached to the movable platen 120 as shown in FIG. 11A instead of being attached to the ejector device 200. The switching cover 620 shown in FIG. 11A closes the entire opening 123 from the internal space 121 side.

When the switching cover 620 is arranged in the internal space 121 of the movable platen 120, the switching cover 620 suppresses the lubricant from scattering from the internal space 121 of the movable platen 120 to the opening 123 in the second state. The adhesion of the lubricant to the opening 123 can be suppressed, and the adhesion of the lubricant to the worker or the work robot performing the connecting work can be reduced. Further, it is possible to prevent the inner peripheral surface of the movable platen 120 from being contaminated with the lubricant.

The switching cover 620 may be arranged in the internal space 121 of the movable platen 120 in the second state in which the scattering of the lubricant is suppressed. The switching cover 620 of the present embodiment is arranged in the internal space 121 in the first state that allows access for connecting work, but the present invention is not limited to this. For example, the switching cover 620 may be arranged in the external space 122 or the opening 123 in the first state that allows access for the connecting work. If the switching cover 620 is arranged in the internal space 121 in the second state regardless of the arrangement in the first state, it is possible to prevent the lubricant from adhering to the opening 123 and to perform a coupling work. Alternatively, the adhesion of the lubricant to the work robot can be reduced. Further, it is possible to prevent the inner peripheral surface of the movable platen 120 from being contaminated with the lubricant.

It should be noted that the switching cover 620 may be arranged in the external space 122 as shown in FIG. 11B instead of being arranged in the internal space 121 of the movable platen 120 in the second state in which the scattering of the lubricant is suppressed. Alternatively, it may be arranged in the opening 123 as shown in FIG. Also in this case, the scattering of the lubricant from the internal space 121 to the external space 122 via the opening 123 of the movable platen 120 can be suppressed.

As shown in FIG. 11B, the switching cover 620 may be attached to the movable platen 120 when arranged in the external space 122 of the movable platen 120. The switching cover 620 shown in FIG. 11B closes the entire opening 123 from the external space 122 side. Further, as shown in FIG. 12A, the switching cover 620 may be attached to the movable platen 120 when it is arranged in the opening 123 of the movable platen 120. The switching cover 620 shown in FIG. 12A closes the entire opening 123 in the middle of the opening 123.

The sliding direction of the switching cover 620 is not limited to the X-axis direction. For example, the sliding direction of the switching cover 620 may be the Y-axis direction or the Z-axis direction. The sliding direction of the switching cover 620 is appropriately selected.

The switching cover 620 may be a slide cover that moves in parallel, a telescopic cover that expands and contracts, or a rotating cover that rotates. The expandable cover may be either a bellows type or a telescopic type. The switching cover 620 shown in FIG. 12B has a rotation cover 629 and a hinge 630. The hinge 630 is attached to the rotary cover 629, and the rotary cover 629 rotates about the pin 631 of the hinge 630. The state shown by the solid line in FIG. 12(b) is the second state in which the scattering of the lubricant is suppressed, and the state shown by the chain double-dashed line in FIG. 12(b) is the first state in which the access for connecting work is permitted. The switching cover 620 shown in FIG. 12B closes the entire opening 123 from the external space 122 side in the second state.

(Modifications, etc.)
Although the embodiment of the injection molding machine and the like have been described above, the present invention is not limited to the above embodiment and the like. Various changes, modifications, substitutions, additions, deletions, and combinations are possible within the scope of the claims. Of course, these also belong to the technical scope of the present invention.

For example, the ejector device 200 of the above embodiment is attached to the movable platen 120 and projects the molded product 20 from the movable mold 820, but the present invention is not limited to this. That is, the ejector device 200 may be attached to the fixed platen 110 and may eject the molded product 20 from the fixed mold 810. In such a case, for example, the mold clamping device 100 is a vertical type.

10 Injection molding machine 100 Mold clamping device 120 Movable platen (platen)
121 Inner Space 122 Outer Space 123 Opening 200 Ejector Device 210 Ejector Rod 220 Ejector Cross Head 230 Drive Mechanism 600 Connector 610 Lubricant Supply 620 Switching Cover 800 Mold Device 820 Movable Mold (Mold)

Claims (2)

A mold clamping device including a platen to which a mold is attached,
An ejector device for ejecting a molded product from the mold,
The ejector device includes an ejector rod, an ejector crosshead to which the ejector rod is connected, and a drive mechanism that moves the ejector crosshead forward and backward.
The platen has an opening for performing an operation of connecting the ejector rod and the ejector crosshead,
The opening allows access from an outer space of the platen to an inner space of the platen, and enables access in a direction orthogonal to a mold opening/closing direction,
A first state that allows the access from the external space to the internal space through the opening, and a second state that suppresses the scattering of the lubricant from the internal space to the external space through the opening. An injection molding machine equipped with a switching cover that switches between and. A cover for an injection molding machine comprising a mold clamping device including a platen to which a mold is attached, and an ejector device for ejecting a molded product from the mold,
The ejector device has an ejector rod, an ejector crosshead to which the ejector rod is connected, and a drive mechanism for moving the ejector crosshead forward and backward.
The platen has an opening for performing an operation of connecting the ejector rod and the ejector crosshead,
The opening allows access from an external space of the platen to an internal space of the platen, and enables access in a direction orthogonal to a mold opening/closing direction,
A first state that allows the access from the external space to the internal space through the opening, and a second state that suppresses the scattering of the lubricant from the internal space to the external space through the opening. Switching cover for injection molding machines that switches to and.