JP2002254380A - Manipulator loaded with vacuum chuck and part assembly method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce load applied on a manipulator body during assembling for enabling assembly work in a unrestricted posture, improve positioning precision and enable assembly of minute parts in a manipulator loaded with a vacuum chuck. SOLUTION: An ultra-small size vacuum chuck 1 is mounted on the manipulator body 2 at the tip part. The vacuum chuck 1 is provided with a relative position fine movement mechanism 15 to maintain a relative position of the manipulator body 2 and a part 4 to be assembled moving in a circle of diameter smaller than positioning precision of the manipulator body 2 in a plane perpendicular to an assembly direction. A reaction force detector to detect a reaction force received during assembling the part 4 to be assembled. Completion of assembly is judged based on the detection result to release the part 14 to be assembled from a part suction mechanism 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a manipulator equipped with a vacuum chuck and a method for assembling parts, and more particularly to a manipulator equipped with a microminiature vacuum chuck used for assembling a micromachine such as a micropump or a miniature machine such as a timepiece. And a component assembling method.

[0002]

2. Description of the Related Art In a factory for assembling precision small machines (miniature machines) such as watches and multimedia home appliances, a manipulator (including a robot) has a vacuum chuck, and picks up and grips parts to carry and transport and assemble. I have. Also, Si
Also in the manufacture of a micromachine such as a micropump manufactured using a micromachining technique, an assembling operation is required for manufacturing a system that integrates a plurality of devices.

As a gripping device effective for assembling a miniature machine or a micromachine, there is a vacuum chuck (prior art 1) described in the 1994 Japan Society of Mechanical Engineers (IV), p. In addition, in the 1996 Annual Meeting of the Japan Society of Mechanical Engineers (IV), page 468, there is a micro gripper that grips a very small material of about several μm (prior art 2).
Studies have been reported. Also, Proceedings of IEEE
On page 72 of -MEMS 97, an electrostatically driven micro gripper (prior art 3) for gripping a component having a diameter of several tens of micrometers is reported as a micro component gripping device. further,
Japanese Patent Application Laid-Open Nos. 8-229750 (Prior Art 4) and 9-267279 (Prior Art 5) describe examples of a gripping tool provided with a fine movement mechanism between a manipulator.

[0004]

The components of a miniature machine or a micromachine are approximately several μm to several m.
It has a size of about m. In order to handle it with high precision and free posture, an ultra-small gripping device that can be mounted on the tip of the assembly manipulator body so that piping and wiring do not hinder the position control of the manipulator is required. Required.

However, in the above-described vacuum chuck of the prior art 1 and the micro gripper of the prior art 2 which grips a very small material of about several μm, the main point is set on how small a component can be gripped. No consideration has been given to miniaturization of its own dimensions, and it is not suitable for mounting on the tip of a manipulator body for assembling a miniature machine or a micromachine that requires precise and complicated work. Further, the electrostatic drive micro gripper of the prior art 3 has a gripping force of 15 nN (1.5 μgf), which is insufficient for application to the assembly of a miniature machine. In any of the gripping devices, no consideration is given to precisely maintaining and controlling the attitude of the gripped component, and the attitude of the component may significantly change during suction.

Further, in the prior arts 4 and 5, since there is no reaction force detector at the time of assembling and only a fine movement mechanism which is displaced linearly, the degree of freedom of fine adjustment in the assembling operation is limited. Is likely to greatly depend on the positioning accuracy of the coarse manipulator.

SUMMARY OF THE INVENTION An object of the present invention is to reduce the load on the manipulator body during assembly, to facilitate assembly work in a free posture, to improve the positioning accuracy, and to reduce the size of the assembly. An object of the present invention is to provide a manipulator equipped with a vacuum chuck capable of easily assembling components and a component assembling method.

[0008]

SUMMARY OF THE INVENTION In order to achieve the above object, a feature of the present invention is to provide a manipulator equipped with a vacuum chuck which moves by mounting a vacuum chuck for gripping an assembly part at a distal end thereof. An ultra-compact vacuum pump, a driving motor for driving the vacuum pump, and a component suction mechanism for sucking and releasing assembly components by a reduced-pressure / positive-pressure atmosphere generated by forward and reverse rotation of the vacuum pump.
A reaction force detector that detects a reaction force from the gripped assembly;
A relative position fine movement mechanism for finely moving the component suction mechanism, and a relative position between a tip end position of the manipulator body and an assembly part gripped by the vacuum chuck is in a plane perpendicular to an assembly direction. The relative position fine movement mechanism is configured to make a circular orbital movement with a diameter smaller than the positioning accuracy of the manipulator body, and a reaction force received when assembling the assembled component to the assembly target component is detected by the reaction force detector. In addition, the present invention is configured to determine the completion of assembly based on the detection result and to detach the assembled component from the component suction mechanism.

[0009] Then, a motor rotary drive type vacuum pump such as a scroll pump or a gear pump is used as a mechanism for generating a reduced-pressure and positive-pressure atmosphere, and is a microminiature mechanism that can be mounted on the tip of the manipulator body for precision assembly.

Further, in order to facilitate the fitting in the assembly of parts, a motor as a driving source is used also as a vacuum pump as a relative position fine movement mechanism of the suction parts, and a rotational output on the opposite side to the vacuum chuck connecting side. By installing an electrostrictive actuator between the eccentric turning mechanism connected to the shaft 12a or the vacuum pump and the component suction mechanism, the diameter is smaller than the positioning accuracy of the manipulator body, and the diameter is perpendicular to the fitting assembly direction. A circular orbit is made in a plane. The drive rotation direction of the vacuum pump is alternately changed between forward and reverse, and the suction and desorption of parts is repeated, so that the relative position of the parts with respect to the tip position of the manipulator body is changed by a displacement amount sufficiently smaller than the positioning accuracy of the manipulator body. I try to change it.

Further, by installing a buffer tank for suppressing pressure fluctuation between the vacuum pump and the component suction mechanism, the time required to return from the reduced pressure atmosphere to the atmospheric pressure becomes longer even if the vacuum pump is stopped after the component suction. Like that.

When the parts are detached, the pump is rotated in the reverse direction to generate a positive pressure atmosphere slightly higher than the atmospheric pressure, and the parts are forcibly released. ing.

[0013] The shape of the component suction mechanism is a nozzle structure at the most advanced structure or a combination of the nozzle structure and a soft sucker, so that components having various shapes can be suctioned, and the posture of the gripped component can be adjusted. The position can be precisely maintained and controlled.

Further, when gripping the assembled component and assembling it into another component, the relative position between the gripped component and the counterpart component is determined.
The step of making a circular orbital motion in a plane perpendicular to the fitting assembly direction with a diameter sufficiently smaller than the positioning accuracy of the manipulator, and the step of measuring the reaction force received when the gripped part comes into contact with the mating part , Or simultaneously and alternately, so that the fitting in the component assembly can be facilitated.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. Note that the same reference numerals in each figure indicate the same or corresponding components.

First, a first embodiment of the present invention will be described with reference to FIGS.

First, an overall configuration of a manipulator (hereinafter, referred to as a manipulator) 100 on which the vacuum chuck of the present invention is mounted will be described with reference to FIG. FIG. 1 is a configuration diagram of a manipulator equipped with a vacuum chuck according to a first embodiment of the present invention.

The manipulator 100 includes an ultra-small vacuum chuck 1 for gripping an assembly component 4 and assembling it into an assembly target component 5, a manipulator body 2 for moving the vacuum chuck 1 to a predetermined position, and a vacuum chuck 1 And a control power supply 3 for controlling the driving of the manipulator body 2
It is composed of The vacuum chuck 1 is mounted on a distal end portion of the manipulator main body 2 and is connected to a control power supply 3 which is separately set at a stationary position via an electric wiring 17. The assembly component 4 and the assembly target component 5 are components constituting a micromachine such as a micropump or a miniature machine such as a timepiece.

The above-described vacuum chuck 1 is a vacuum pump 1
1, its driving motor 12, piping 13, electric wiring 17,
It comprises a component suction mechanism 14, a relative position fine movement mechanism 15, and a reaction force detector 16, which are integrally formed.
The vacuum pump 11 is driven by a driving motor 12 and sucks air from a component suction machine 14 through a pipe 13. The relative position fine movement mechanism 15 performs fine movement of the vacuum chuck 1 and is installed on the manipulator body 2 side of the drive motor 12. Further, the reaction force detector 16 is for detecting whether the vacuum chuck 1 has gripped the assembly part 4 or whether the assembly part 4 has been fitted to the assembly target part 5. It is installed on the suction mechanism 14 side.

The manipulator 100 includes a vacuum chuck 1
By controlling the manipulator main body 2 by the control power supply 3, the assembling part 4 is gripped and moved, and an operation of assembling the assembling part 4 to the to-be-assembled part 5 placed at another position is performed. Here, the vacuum chuck 1 is configured integrally with the component suction mechanism 14 from the vacuum pump 11 and mounted on the distal end portion of the manipulator main body 2, so that only the electric wiring 17 is connected to the control power supply 3 in the stationary position. And the obstacle to the operation of the manipulator 100 is reduced. As a result, the gripping posture of the assembly component 4 and the movement of the manipulator 100 can be freely selected, and a multi-degree-of-freedom assembly operation can be performed.

Next, details of the vacuum chuck 1 will be described with reference to FIGS. FIG. 2 is a sectional view of a vacuum chuck used for a manipulator equipped with the vacuum chuck of FIG.
FIG. 3 is a sectional view taken along line AA of FIG.

The vacuum chuck 1 has a scroll type vacuum pump 11 and a drive motor 12 at the center. The vacuum pump 11 has, on one side, a pipe 13 and a component suction mechanism 14 connected to a suction port 116 of the vacuum pump 11 via a buffer tank (pressure vessel) 117. In this way, even if the driving of the vacuum pump 11 is stopped in a state in which the assembly part 4 is sucked, the time required to return from the reduced pressure atmosphere to the atmospheric pressure becomes longer by passing through the buffer tank 117,
The assembly of the assembly target component 5 can be completed while maintaining the grip of the assembly component 4, and the mechanical vibration and heat generation during the component transportation are reduced, so that the positioning accuracy of the manipulator 100 is improved. 4 is less affected by heat, and power consumption can be reduced.

The vacuum chuck 1 includes a driving motor 1
The second rotation shaft 12a also protrudes toward the manipulator main body 2, and the relative position fine movement mechanism 15 is connected to this.
The relative position fine movement mechanism 15 is also fixed to the distal end portion of the manipulator main body 2, whereby the vacuum chuck 1 is moved.
Is mounted on the tip of the manipulator body 2. The relative position fine movement mechanism 15 includes an eccentric turning mechanism 151,
It comprises an attachment member 152 to the drive motor 12 and an attachment member 153 to the manipulator body 2. The eccentric turning mechanism 151 includes a rotating shaft 151a that rotates eccentrically by driving the rotating shaft 12a of the drive motor 12, and a disk member 15 that rotates eccentrically by the rotating shaft 151a.
1b, the disk member 151b and the mounting member 15
2 and 153. With this relative position fine movement mechanism 15, the relative position of the assembly part 4 with respect to the distal end position of the manipulator body 2 can be finely moved by a displacement that is sufficiently smaller than the positioning accuracy of the manipulator body 2.
Adjustment at the time of assembling / fitting to the device becomes very easy.

As described above, the vacuum pump 11 uses a scroll type pump. The scroll type pump has a small number of parts and has a very simple assembly structure, and thus is suitable for microfabrication. That is, by making the vacuum pump 11 that is most needed for microfabrication, it is possible to achieve microfabrication of the entire vacuum chuck 1.

The scroll type vacuum pump 11 includes a fixed scroll 111, a orbiting scroll 112, a shaft 113,
A casing 114 and a bearing 115; Shaft 113
Is supported by a casing 114 via a bearing 115, and is connected to the orbiting scroll 112 via the bearing 115 at a shaft portion eccentric with respect to the rotation shaft 12 a of the drive motor 12. The orbiting scroll 112 is configured to perform an orbiting motion in combination with the fixed scroll 111.

In this structure, when the shaft 113 is rotated by the driving motor 12, the orbiting scroll 112 revolves and the closed space having a small gap formed between the orbiting scroll 112 and the fixed scroll 111 is formed by the suction port 116. , And gradually acts toward the discharge port 118. As a result, the fluid in the closed space is supplied, and a pump action occurs.

The involute curves, which are the basis of the scroll shapes of the fixed scroll 111 and the orbiting scroll 112, were determined by the following formula using polar coordinates.

Outer curve X = A (cos θ + θ sin θ) Y = A (sin θ−θ cos θ) Inner curve X = A (cos θ + (θ−t / A) sin θ) Y = A (sin θ− (θ−t / A) cos θ) where A is the radius of the base circle and 0.175 m in this embodiment.
m and t are 0.25 mm in the thickness of the scroll. Further, the height of the scroll was 1.5 mm. Therefore, the aspect ratio of the scroll cross section is 6. Also,
The theoretical displacement per rotation of the scroll was set to about 4 μl.

In a scroll pump of normal size which has already been widely used, in order to prevent the orbiting scroll from rotating,
Although an Oldham ring is used, in this embodiment, in order to realize an ultra-small structure, as shown in FIG. 3, both the orbiting scroll 112 and the casing 114 are provided with three circular guide grooves 119, respectively. Steel balls 1191 are respectively inserted in them to prevent the orbiting scroll 112 from rotating. Note that a solid cylindrical member may be used instead of the steel ball 1191.

Next, a modification of the anti-rotation mechanism will be described with reference to FIGS. FIG. 4 is a diagram showing a first modification of FIG. 3, and FIG. 5 is a diagram showing a second modification of FIG.

The anti-rotation mechanism shown in FIG. 4 has four guide grooves 119 and four steel balls 1191, and the anti-rotation mechanism shown in FIG. 5 has eight guide grooves 119 and eight steel balls 1191. The number of guide grooves 119 of the anti-rotation mechanism is required to be at least three in order to define a plane. In that case, the frictional force between the orbiting scroll 112 and the casing 114 can be reduced. On the other hand, when the number of the guide grooves 119 is large, the moment load on the drive motor shaft 12a is reduced, and the guide grooves 119 and the orbiting scroll side bearing 115 are reduced.
Wear is reduced. However, when the number of the guide grooves 119 is large, the frictional force increases, and the vibration with a large gap with the steel ball 1191 tends to increase due to the variation in the depth of the guide grooves 119.

As a structural material of the vacuum pump 11, an aluminum material is used for the fixed scroll 111 so as to reduce the weight and facilitate mounting on the manipulator body 2, and the amount of wear caused by the steel balls 1191 is used for the orbiting scroll 112. Cast iron material is used to reduce this. The entire structure of the fixed scroll 111 and the orbiting scroll 112 is processed using a precision lathe and a milling machine, and the scroll portion is processed using an NC end mill. And the diameter of the end mill tool used is 0.6 mm,
The scroll portion at 0.8 mm intervals is milled along a single stroke. The assembly of these parts was performed using M1 bolts and an adhesive. It should be noted that, depending on the application, the material of the combination is not limited, and for example, a combination of aluminum, cast iron, resin, or the like may be selected. Next, the dependence of the exhaust speed on the driving speed in the scroll vacuum pump 11 will be described with reference to FIG. FIG. 6 is a characteristic diagram of the exhaust speed in the scroll type vacuum pump used in FIG. The vacuum pump 11
The driving motor 12 has a diameter of 10 mm and a length of about 2 mm.
A motor with a maximum output of 1.2 W of 0 mm is used.

As shown in FIG. 6, the vacuum pump 11 can obtain a monotonically increasing pumping speed within the range of the operating voltage of the driving motor 11, that is, the rotation speed. The maximum value is about 70 ml / min, and the driving speed at that time is about 2
Since it is 0000 rpm, the displacement per one rotation of the scroll is about 3.5 μl, and the volumetric efficiency with respect to the theoretical displacement is 0.9.

Next, the vacuum pump 11 which is a rotary pump
Will be described with reference to FIGS. 7 and 8. FIG. FIG. 7 is a sectional view of a first modification of the vacuum pump of FIG. 2, and FIG. 8 is a sectional view of a second modification of the vacuum pump of FIG.

The vacuum pump 11 shown in FIG. 7 is a gear pump, and the vacuum pump 11 shown in FIG. 8 is a vane pump. These pumps 11 are pumps that form a plurality of closed spaces and rotate them as shown by thin arrows, thereby increasing or decreasing the volume of each space, and continuously sucking and discharging as shown by thick arrows. is there. Among these, the gear pump 11 has a large gas leakage between the gears and a low efficiency, but can be used as a micro pump. Also,
The vane type pump 11 has a complicated structure in which many movable vanes are inserted into a part of the rotor in order to reduce gas leakage, but can be used as a micro pump.

Next, details of the component suction mechanism 14 will be described with reference to FIGS. FIG. 9 is a sectional view of the component suction mechanism of FIG. 1, and FIG. 10 is a sectional view taken along line BB of FIG.

The component suction mechanism 14 picks up the assembled component 4
After being gripped and fitted to the assembly target component 5, the assembly component 4 is released, and is configured by a combination of a nozzle 141 and a suction cup 144. The nozzle 141 or the suction cup 1
It is also possible to constitute the component suction mechanism 14 by itself.

The nozzle 141 is formed by vertically fixing a first cylindrical member 141a and a second cylindrical member 141b, and has a suction hole 142 penetrating vertically.
The suction hole 142 is formed in the first cylindrical member 141a.
The second cylindrical member 141b has a tapered hole 142a whose inner diameter gradually decreases from the assembly component 4 side to the vacuum pump 11 side, a constant inner diameter hole 142b that follows, and an enlarged hole 142c that follows. It has a branch hole 142d following it. The first cylindrical member 141b is attached to the pipe 13, and thereby the component suction mechanism 1
Reference numeral 42 is connected to the vacuum pump 117 via the pipe 13.

Specifically, the opening diameter of the tapered hole portion 142a is set to a value obtained by adding the positioning accuracy of the manipulator body 2 to approximately twice the outer diameter of the shaft portion 4a of the assembly part 4. For example, if the outer diameter of the assembly 4 is 100 μm and the positioning accuracy of the manipulator body 2 is 50 μm, the opening diameter is 2 μm.
It is about 50 μm. By providing the tapered hole 142a, even if a positional error occurs between the assembly part 4 and the component suction mechanism 14 due to a positioning error of the manipulator body 2, the upper end of the shaft part 4a of the assembly part 4 is tapered.
If it is located within the range of the opening a, the shaft portion 4a is inserted into the suction hole 142, and the assembly component 4 can be sucked and gripped. The inner diameter of the hole 142b having a constant inner diameter is desirably a value obtained by adding about several μm to several tens of μm to the outer diameter of the assembly 4.
Thus, the posture position of the gripped assembly 4 can be precisely maintained in a state where the assembly 4 shaft 4a is inserted into the hole 14b. The longer the depth of the hole 142b having a constant inner diameter is, the more effective it is to maintain the posture of the assembly component 4.

The suction cup 144 is made of a rubber material having a soft and smooth surface, the upper part 144a is mounted on the nozzle 141, the central part 144b is bellows-shaped, and the axial length can be largely changed. 144c has an enlarged shape. By doing so, it is possible to effectively grip the dimensional change of the assembly part 4 and secure a sufficient suction area.

In the component suction mechanism 14, when the shaft portion 4a of the assembly 4 enters the tapered hole 142a and is guided by the tapered slope to enter the hole 142b having a constant inner diameter, the nozzle hole 142 and the assembly 4 are connected to each other. Due to the pressure loss due to the airflow during the period, a pressure difference occurs between the front and rear of the assembly part 4, and the shaft part 4a of the assembly part 4 is sucked into the deep part of the nozzle 141 (upper part in FIG. When the assembly 4 has an axial shape, the nozzle 1
Suction / gripping occurs only with 41. In the case where the assembly component 4 is a flat plate with a shaft as shown in FIG. 7, the surface of the flat plate portion 4b is brought into contact with and sucked by the suction cup 144, so that suction and grip occur. And
In any case, the position and orientation of the component are maintained with high accuracy by the nozzle 141. When the assembly 4 is a plate or a block without a shaft, suction is caused only by the suction cup 144. In this case, it is possible to hold components of various shapes that are not restricted by the shape of the component.

As described above, by combining the component suction mechanism 14 with the nozzle 141 and the soft suction cup 144, components having various shapes can be suctioned, and at the same time, the posture of the component grasped.・ Position can be precisely maintained.

Here, the nozzle 1 is used as the component suction mechanism 14.
The attraction force when only 41 is used will be described with reference to FIG. FIG. 11 is a characteristic diagram of the suction force of only the nozzles of the component suction mechanism of FIG. The attraction force characteristic is obtained by measuring the attraction force with respect to a voltage applied to a driving motor required at the time when the assembly part 4 of the minute gear is attracted.

FIG. 11 shows a component suction mechanism 14 having only nozzles.
As apparent from the above, it is possible to obtain an attraction force proportional to the voltage applied to the motor. Then, in this example, it was confirmed that by adjusting the input voltage to the motor to 3.4 V or more, it is possible to obtain an adsorption force of 0.06 mN (6 mgf) or more.

The soft suction cup 1 is used as the component suction mechanism 14.
The measurement results of the attraction force when only 44 is used will be described. The suction force of the component suction mechanism 14 using only the rubber suction cup 144 having a diameter of 7 mm is approximately 10,000 r.
It was confirmed that a maximum of about 0.7 N (70 gf) or more can be obtained at pm or more.

Next, a modification of the component suction mechanism 14 is shown in FIG.
This will be described with reference to FIG. FIG. 12 is a sectional view showing a modification of the component suction mechanism of FIG. 9, and FIG.
It is sectional drawing.

In the component suction mechanism 14, the nozzle 141
A plurality of cores 145 are installed inside. In this modification, four cores are shown, but it is sufficient if at least two cores. In this structure, when the assembly component 4 enters the component suction mechanism 14, it is sucked together with the core 145. Here, by adding the core 145, even when the outer diameter of the shaft-shaped component is different, an effect is obtained that a similar gripping force can be obtained within the gap value range between the core 145 and the nozzle 141.

Next, the operation of the above-described manipulator 100 will be described with reference to FIGS.

The operation from positioning by the manipulator 100 to gripping of the assembly 4 will be described with reference to FIG. FIG. 14 is an operation flowchart from positioning by a manipulator equipped with the vacuum chuck of FIG. 1 to gripping of an assembly part.

In FIG. 14, a known teaching playback system is used for positioning the manipulator body 2. That is, first, the manipulator body 2 is manually moved to a desired position (step 201), the three-dimensional position coordinates of the position are stored, and the sequence is positioned at the time of executing the sequence. In the coordinate system, the component fitting direction is defined as a Z axis, and a plane perpendicular to the Z axis is defined as an XY plane. When the XY coordinates of the component suction position match the value stored in advance (step 202), a chuck instruction signal is transmitted (step 203).

When this signal is received (step 20)
4) While the vacuum pump is driven to rotate in the forward direction to generate a reduced-pressure atmosphere (step 205), the manipulator main body 2 is gradually lowered (step 206), and the assembled component 4 is sucked by the vacuum chuck 1. Whether the assembled component 4 has hit the end point of the component suction mechanism 14 is detected by the reaction force detector 16 installed on the vacuum chuck 1 (step 207), and the lowering of the manipulator body 2 is stopped (step 208). When the set time has elapsed (step 209), a chuck completion signal is transmitted (step 210).

When this signal is received (step 21)
1) Stop the vacuum pump 11 (step 21)
2). Here, the reduced pressure atmosphere is maintained by installing the buffer tank 117, and the suction of the assembly component 4 is continued without driving the vacuum pump 11. Then, the manipulator body 2 is raised at a low speed (step 213), it is confirmed whether the XY coordinates are set (step 214), and the lifting of the manipulator body 2 is stopped (step 215).

The sequence of this embodiment is characterized by ON / OFF timing of the vacuum pump 11 and detection of the reaction force. In the present embodiment, the positioning method based on the teaching playback is employed. However, a so-called master-slave method in which the manipulator is artificially controlled while observing the movement of the manipulator, or a combination of the two is also effective.

The operation of the manipulator 100 from gripping to release of the assembly will be described with reference to FIG. FIG. 15 is an operation flowchart from gripping to detachment of an assembly component by the manipulator equipped with the vacuum chuck of FIG.

In FIG. 15, the assembly part 4 is moved by the manipulator body 2 to the fitting position of the part 5 to be assembled in a state where the assembly part 4 is sucked by the vacuum chuck 1 (the vacuum pump may be kept off) (step 221). When fitting the assembly component 4 to the assembly target component 5, when the XY coordinates of the tip of the assembly component 4 have moved to the fitting position stored in advance (step 222), the drive motor 12 of the vacuum chuck 1 is turned on. Drive forward. As a result, the vacuum pump 11 performs the normal rotation operation (step 223),
The eccentric turning mechanism 151 connected to the rotating shaft 12a of the drive motor 12 operates to move the vacuum chuck 1 so as to draw a circular orbit with respect to the manipulator body 2 (step 2).
24). Accordingly, the assembly 4 also moves in a circular orbit.

Then, by the operation of the manipulator main body 2, the assembly component 4 gradually descends while moving in a circular orbit (step 225). Whether the assembly component 4 is fitted to the assembly target component 5 is lowered at the fitting position while detecting the reaction force received by the assembly component 4 from the assembly target component 5, and the portion where the reaction force is reduced is fitted. It is recognized as having been done (step 226). If it is recognized that the fitting has been performed, the driving of the driving motor 12 is stopped to stop the circular orbital movement of the assembly component 4 (step 227), and
Stop the lowering of the manipulator body 2 (step 22
8) Send a release stop signal (step 22)
9).

When the release instruction signal is detected (step 230), the driving motor 12 of the vacuum chuck 1 is started in the reverse direction. Thereby, the vacuum pump 1 of the vacuum chuck 1
1 performs reverse operation (step 231), retracts the vacuum chuck 1 with the manipulator body 2 while forming a positive pressure atmosphere (step 232), and detaches the assembly part 4 from the vacuum chuck 1. It is checked whether the retracted manipulator body 2 is at the set XY coordinates (step 233), and the ascent of the manipulator body 2 is stopped (step 234).
Then, the operation of the vacuum pump 11 is stopped (step 23).
5) Send a release completion signal (step 23)
6).

When this release completion signal is received (step 237), the manipulator body 2 operates to return to the origin (step 238).

The present embodiment is characterized in that components are fitted by circular orbital motion and reaction force detection, and the assembly component 4 is detached by utilizing a positive pressure atmosphere due to the reverse rotation of the vacuum pump 11. The vacuum pump 11 is driven alternately in the forward and reverse directions without detecting the reaction force, and is lowered while detecting the reaction force. They may be fitted.

With the above operation sequence, positioning and
At the time of fitting, even if displacement occurs in a random direction in the XY plane due to the limit of positioning accuracy of the manipulator, fine adjustment is made by circular orbital movement while monitoring the assembly reaction force. A suitable position for fitting can be found more easily than the method of finely moving linearly regardless of the position. As a result, high-precision suction and grip of parts using vacuum chucks, transport and positioning with manipulators,
The detachment is performed, and as a whole, a high-precision assembling operation of minute components is realized.

Next, a second embodiment of the present invention will be described with reference to FIGS. FIG. 16 is a sectional view of a vacuum chuck of a manipulator having a vacuum chuck according to a second embodiment of the present invention, and FIG. 17 is a sectional view taken along line DD of FIG.

The difference between the present embodiment and the first embodiment is the position and structure of the relative position fine movement mechanism 15. That is, in the present embodiment, the relative position fine movement mechanism 15 is located between the buffer tank 117 of the vacuum pump 11 and the component suction mechanism 14 so that the flexible pipe 13 connected to the component suction mechanism 14 is sandwiched from the side. An electrostrictive actuator 152 is provided. With the structure of the present embodiment, the position of the component suction mechanism 14 can be changed by a displacement that is sufficiently small compared to the positioning accuracy of the manipulator body 2. In addition, 2
By exciting the electrostrictive actuators 152 with AC voltages having a phase shift of 90 degrees from each other,
Can be moved relative to each other in a circular or elliptical orbit. Relative position fine movement mechanism 1 of this structure
Adopting 5 makes it very easy to assemble and fit the assembly component 4 to the assembly target component 5 with a small structure. Further, in the present embodiment, compared to the structure of the first embodiment, the size of the member to be finely moved is small and the weight is very light, so that the vibration load on the manipulator is reduced, and as a result, the positioning accuracy is improved. be able to.

In this embodiment, the scroll pump 1
1 so that it can be mounted on the tip of the manipulator body 2 for precision assembly.
The load on the device is reduced, the assembling work in a free posture is facilitated, and the positioning accuracy can be improved. Also, the adoption of the relative position fine movement mechanism 15 for the suction component allows the fitting to be performed very easily. In addition, by adopting the buffer tank 117 that suppresses pressure fluctuations, after the vacuum pump 11 is stopped at the time of gripping parts, the time required to return from the reduced pressure atmosphere to the atmospheric pressure becomes longer, thereby suppressing vibration and heat generation and positioning the parts. Accuracy can be improved. Furthermore, by using the nozzle 141 structure or the combination of the nozzle 141 structure and the soft suction cup 144 as the most advanced structure of the component suction mechanism 14, components having various shapes can be suctioned. In addition, by monitoring the reaction force at the time of fitting and finely adjusting the relative position of the gripped parts by circular orbital movement, it is possible to easily assemble minute parts.

[0064]

As described above, according to the present invention, the load on the manipulator body at the time of assembly can be reduced, the assembling work in a free posture can be easily performed, and the positioning accuracy can be improved. In addition, a manipulator and a component assembling method equipped with a vacuum chuck capable of easily assembling minute components can be obtained.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a manipulator equipped with a vacuum chuck according to a first embodiment of the present invention.

FIG. 2 is a sectional view of a vacuum chuck used in a manipulator on which the vacuum chuck of FIG. 1 is mounted.

FIG. 3 is a sectional view taken along line AA of FIG. 2;

FIG. 4 is a diagram showing a first modification of FIG. 3;

FIG. 5 is a diagram showing a second modification of FIG. 3;

FIG. 6 is a characteristic diagram of the exhaust speed in the scroll vacuum pump used in FIG.

FIG. 7 is a sectional view of a first modification of the vacuum pump of FIG. 2;

FIG. 8 is a sectional view of a second modification of the vacuum pump of FIG. 2;

FIG. 9 is a sectional view of the component suction mechanism of FIG. 1;

FIG. 10 is a sectional view taken along the line BB of FIG. 9;

11 is a characteristic diagram of the suction force of only the nozzles of the component suction mechanism of FIG. 9;

FIG. 12 is a sectional view showing a modification of the component suction mechanism of FIG. 9;

FIG. 13 is a sectional view taken along the line CC of FIG. 12;

14 is an operation flowchart from positioning by a manipulator equipped with the vacuum chuck of FIG. 1 to gripping of an assembly component;

FIG. 15 is an operation flowchart from gripping to detachment of an assembly component by a manipulator equipped with the vacuum chuck of FIG. 1;

FIG. 16 is a sectional view of a vacuum chuck of a manipulator equipped with a vacuum chuck according to a second embodiment of the present invention.

FIG. 17 is a sectional view taken along line DD of FIG. 16;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Vacuum chuck, 2 ... Manipulator main body, 3 ... Control power supply, 4 ... Assembly parts, 5 ... Assembly parts, 11 ... Vacuum pump, 12 ... Driving motor, 13 ... Piping, 14 ... Parts suction mechanism, 15 ... Relative Position fine movement mechanism, 16 ... reaction force detector,
Reference Signs List 17: electric wiring, 100: manipulator, 111: fixed scroll, 112: orbiting scroll, 113: shaft, 114: casing, 115: bearing, 116: suction port, 117: buffer tank, 118: discharge port, 11
9 Guide groove, 141 nozzle, 141a first cylindrical member, 141b second cylindrical member, 142 suction hole, 1
44: suction cup, 145: core, 151: eccentric turning mechanism, 1
52 ... Electrostrictive actuator.

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (Reference) B25J 17/02 B25J 17/02 A B81C 5/00 B81C 5/00 (72) Inventor Yoshishige Endo Jindatecho, Tsuchiura-shi, Ibaraki Pref. 502 Machinery Research Laboratories, Hitachi, Ltd. (72) Inventor Tatsuo Natori 502, Kantachi-cho, Tsuchiura-shi, Ibaraki Prefecture F-term, Machinery Research Laboratories, Ltd.F-term (reference) 3C007 AS07 BT01 BT18 DS01 FS01 FT02 FU00 GU03 HS03 HS27 HS29 KS28 KS34 KX07 LV17 3C030 AA08 AA15 AA22 AA23 BC02 BC25 BC27

Claims (11)

[Claims] 1. A manipulator equipped with a vacuum chuck which moves by mounting a vacuum chuck for gripping an assembly component at a tip thereof, wherein the vacuum chuck comprises an ultra-small vacuum pump and a driving motor for driving the vacuum pump. A component adsorption mechanism for adsorbing / desorbing an assembly part by a reduced-pressure / positive-pressure atmosphere generated by forward / reverse rotation of the vacuum pump; a reaction force detector for detecting a reaction force from the gripped assembly part; A relative position fine movement mechanism for finely moving the suction mechanism, wherein a relative position between a tip end position of the manipulator body and an assembly part gripped by the vacuum chuck is in a plane perpendicular to an assembly direction. The relative position fine movement mechanism is configured to make a circular orbital movement with a diameter smaller than the positioning accuracy of the manipulator body, and assemble the assembly parts to the assembly target parts. A vacuum chuck, characterized in that the reaction force received by the reaction force detector is detected by the reaction force detector, assembly completion is determined based on the detection result, and the assembled component is detached from the component suction mechanism. Manipulator. 2. The relative position fine movement mechanism is provided with an eccentric turning mechanism which is driven also as the drive motor of the vacuum pump and is connected to a motor rotation output shaft on the side opposite to the vacuum pump installation side. A manipulator equipped with the vacuum chuck according to claim 1. 3. The manipulator according to claim 1, wherein the relative position fine movement mechanism is an electrostrictive actuator installed between the vacuum pump and the component suction mechanism. 4. The reaction force detector according to claim 1, wherein said reaction force detector is a reaction force detector based on a principle of displacement-stress conversion integrally formed with said component suction mechanism. Manipulator equipped with a vacuum chuck. 5. The scroll pump according to claim 1, wherein the vacuum pump is a scroll pump.
The manipulator equipped with a vacuum chuck according to any one of claims 1 to 4, wherein the manipulator is a motor rotary drive type pump such as a vane type pump or a gear type pump. 6. A vacuum chuck according to claim 1, wherein a buffer tank for suppressing pressure fluctuation is provided between the suction port of the vacuum pump and the component suction mechanism. Manipulator. 7. The component suction mechanism includes a nozzle having a tapered hole portion whose inner diameter gradually decreases from the assembled component side to the vacuum pump side, and a nozzle portion having a constant inner diameter following the nozzle portion. Item 7. A manipulator on which the vacuum chuck according to any one of Items 1 to 6 is mounted. 8. The manipulator mounted with a vacuum chuck according to claim 1, wherein said component suction mechanism comprises a soft suction cup having an exhaust hole in a central portion and a nozzle fitted in the hole. 9. A vacuum chuck for assembling by assembling and assembling said assembly part at a predetermined position of a part to be assembled by sucking and desorbing the assembly part using a reduced pressure and positive pressure atmosphere generated by a vacuum pump. In a component assembling method for assembling parts using a manipulator having a manipulator body having a vacuum chuck mounted at a tip thereof, a step of positioning the manipulator body when assembling an assembly part into a part to be assembled, Measuring the reaction force received when the manipulator comes into contact with the assembly target component, and the manipulator body in a plane in which the relative position of the assembly gripped by the vacuum chuck by the relative position fine movement mechanism is perpendicular to the fitting assembly direction And performing a circular orbital motion with a diameter smaller than the positioning accuracy of the component. 10. The relative position between the assembly component and the assembly target component is smaller than the positioning accuracy of the manipulator body by repeating the suction and desorption of the assembly component by alternately changing the drive rotation direction of the vacuum pump forward and reverse. The component assembling method according to claim 9, wherein the component is fitted to the component to be assembled by performing relative movement by the displacement amount. 11. The driving direction of the vacuum pump is alternately changed between positive and negative.
A vacuum chuck mounted on the tip of a positioning manipulator that adsorbs and desorbs parts using the reduced pressure and positive pressure atmosphere generated by the control power supply to be reversed and fits it into a predetermined position of one of the parts to be assembled and assembles it A relative position fine movement mechanism in which a relative position between the distal end position of the manipulator and a grip target component gripped by the vacuum chuck moves in a circular orbit with a diameter smaller than the positioning accuracy of the manipulator in a plane perpendicular to the fitting and assembly direction; A vacuum chuck having means for measuring a reaction force received when a grip target component comes into contact with an assembly target component.