JPS6361094B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a workpiece tracking device in a press brake, and more specifically, in a press brake that bends a workpiece, it is possible to perform box bending in particular without being affected by the deflection of the workpiece. The present invention relates to a workpiece tracking device that can sufficiently perform its functions even when the workpiece is to be used, maintains accuracy, and is easy to maintain.

Generally, in a press brake that bends a plate-shaped workpiece by approaching and separating an upper apron and a lower apron, when bending the workpiece, the part of the workpiece protruding forward from the apron is It supports the part as it flips up and prevents second bending (unnecessary bending caused by inertia, own weight, etc. of the part of the workpiece that protrudes forward during bending).

Conventionally, in this type of tracking device, a detector that directly detects the bending of the workpiece is provided on the support itself that is to be moved to follow the bending of the workpiece, and the operation of this detector (for example, the position of the bending angle of the workpiece) is This is a device that performs detection, and when the workpiece bends faster and the supporter follows slower, it detects the lifting of the workpiece itself relative to the supporter and controls the supporter to speed up the following movement, and vice versa. (detection operation for controlling to limit the follow-up operation), the support body supporting the workpiece is pushed up by the cylinder.

However, in such conventional devices, since the above-mentioned detector is provided on the support itself that supports the work, detection errors may occur depending on the deflection of the work, for example in the case of a work that is easy to bend and in the case of a work that is difficult to bend. Errors occur due to the deflection of the workpiece, especially when bending a workpiece that does not stand up on both sides and when bending a workpiece that stands up on both sides, such as box bending. It will occur in a big way. In addition, since the above-mentioned detection operation is used, control using, for example, a servo valve is required, and the detection accuracy varies depending on the performance and inclination angle of the detector and this servo valve, especially when bending a box. It has drawbacks such as not being able to fully demonstrate its function, and maintaining the accuracy and maintenance of the detector etc. is difficult.

This invention eliminates the above-mentioned drawbacks, and eliminates the need for a detector that has various problems such as detection errors caused by bending of the workpiece. In particular, even when box bending It is an object of the present invention to provide a workpiece tracking device that is not affected by the above effects, maintains accuracy, and is easy to maintain.

In this invention, the amount of movement of a movable apron in a press brake is detected, and a follow-up arm that corresponds to the amount of movement of this movable apron from the start of bending a workpiece and has a follow-up amount of a predetermined ratio with respect to this amount of movement is provided. By driving the following arm, the following movement of the following arm corresponds to the bending depth of the workpiece.

A preferred embodiment of the present invention will be described below with reference to the accompanying drawings.

1 and 2 show a side view and a plan view of a workpiece following device in a press brake according to the present invention.

In FIG. 1, an upper apron 5 is fixed to the upper part of the frames 3 (the frame shown is the right frame) installed on the left and right sides of the press brake 1 so that the left and right direction of the press brake 1 is the longitudinal direction. The upper apron 5 has an upper mold 7 on its lower surface. On the other hand, a plurality of cylinders 13 are provided between the rear plate 9 and the front plate 11 fixed to the lower part of the left and right frames 3, and a plurality of cylinders 13 are provided on the upper surface of the piston 15, with the left and right direction of the press brake 1 being the longitudinal direction. A lower apron 17 is provided, and the lower apron 17 has a lower mold 19 on its upper surface.

The press brake 1 is a so-called ascending press brake in which the lower apron 17 is a movable apron that can be raised and lowered.
The workpiece W is bent as described later by the engagement of the lower die 19 and the lower die 19.

The workpiece tracking device applied to the ascending press brake 1 having the above configuration includes, for example, a detection mechanism 21 provided in relation to the front plate 11 and the lower apron 17.
1, a follower arm 23 disposed in front of the lower die 19 (on the right side in FIG. 1), and a drive mechanism 25 for driving the follower arm 23.

First, this drive mechanism 25 and follower arm 23
This will be explained with reference to FIG. 1, FIG. 2, and FIG. 3 showing the main parts of the drive mechanism 25.

In FIG. 1, on the front surface of the lower apron 17, a vertical slide 27 can be attached and detached to the left and right (vertical direction in FIG. 2) as shown in FIG. 2, dividing the longitudinal center of the lower apron 17. It is set in. Each vertical slide 27 is provided with a rotatable screw rod 29 in the vertical direction.
A transmission means 31 such as a bevel gear is fixed to the lower end of each screw rod 29, respectively. In addition, each of the screw rods 2
The end portions 35 of each of the longitudinal slides 33 are screwed into each of the end portions 9 , and each of the end portions 35
5 are slidably guided by the vertical guide portions 37 of the vertical slides 27, respectively, as shown in FIG.

In addition, in FIG. 2, a mold height adjustment handle 39 (the vertical position of the longitudinal slide 33 with respect to the lower mold 19) is located at the bottom of the outer surface of the right vertical slide 27 (the upper vertical slide in FIG. A shaft 41 that passes through the handle 39 and rotates integrally with the vertical slide 2
7 and is rotatably supported. Furthermore, this axis 4
1, as shown in FIG. 1, is integrally provided with transmission means 43 such as bevel gears that engage with each transmission means 31 such as a bevel gear at the end of the screw rod 29 of each vertical slide 27.

By rotating the mold height adjustment handle 39, each screw rod 29 is rotated via the shaft 41, each transmission means 43, and each transmission means 31.
Each of the longitudinal slides 33, whose end portions 35 are screwed into each screw rod 29, moves in the vertical direction (for example, within a range of approximately 60 mm).

Further, in FIG. 1, a shaft 47 having a transmission means 45 such as a worm wheel is rotatably supported on the right end of each of the longitudinal slides 33 that can slide in the vertical direction. The left side of constitutes a screw rod. And each axis 47
The screw rods are screwed into the lower part of each side plate 49. Furthermore, in FIG. 2, the right front-back slide 33
A V width adjustment handle 51 is provided on the outside of the
This handle 51 has a shaft 5 that rotates integrally with it.
3 is provided. And on this shaft 53,
As shown in FIG. 1, a transmission means 55, such as a worm, is provided which engages each transmission means 45, such as a worm wheel.

By rotating the V-width adjustment handle 51, each shaft 47 is rotated via the shaft 53, each transmission means 55, and each transmission means 45, and the lower part thereof is screwed into the left threaded rod portion of each shaft 47. Each of the side plates 49 moves in the front-back direction (for example, within a range of about 15 mm) relative to the front-back slide 33.

1 and 3, a rotation shaft 59 of a link mechanism 57 is supported on the side surface of the side plate 49, and a piston rod 63 of a follower cylinder 61 provided outside the right end of the side plate 49 is supported. It is configured to rotate around the V-shaped shoulder 19a of the lower die 19 upon extension. Note that this follow-up cylinder 61 is movable in the longitudinal direction along the longitudinal slide 33 separately from the side plate 49. This movement is performed using fasteners such as bolts.

That is, the piston rod 63 of the following cylinder 61 is connected to the connecting plate 6 of the link mechanism 57.
A rotary shaft 69 guided in a long hole 67 formed in the front-rear direction of the side plate 5 is rotatably supported, and is guided in the front-rear direction by a guide plate 71 erected on the right side of the side plate 49. Further, the upper rotating shaft 73 of the link mechanism 57
A guide bar 75 is rotatably supported on the shaft.

The link mechanism 57 and the follow-up cylinder 61 that constitute the drive mechanism 25 mentioned above are operated as described below, so that
Following arm 2 which will be described below via link mechanism 57
Drive 3.

That is, in FIGS. 1 and 2, a follower arm 23 is shown without a detector, as is required in the previously described prior art devices.
As shown in FIG. 2, the following arm 23 is provided on the upper surface of the guide bar 75 extending left and right so as to be movable in the left and right directions. The left and right follower arms 23 are provided with a workpiece adsorption member 7 that adsorbs the workpiece W.
A plurality of follower arm fixing handles 7 are provided at the bottom of each follower arm 23, and each follower arm fixing handle 7 fixes the left and right movement of each follower arm 23 with respect to the guide bar 75.
9 are screwed together.

The follower arm 23 can move using the guide bar 75 as a guide, and can be fixed at any position by the follower arm fixing handle 79 according to the needs of the operator, for example, and also has a work support function.

Next, the detection mechanism 21 will be explained with reference to FIG. 1 and FIG. 4 showing the main parts of the detection mechanism 21.

In FIG. 4, a shaft 83 having a tracking start setting handle 81 is rotatably supported on the front side of the lower apron 17, and this shaft 83 is attached to the front surface of the lower apron 17 with a fastener such as a bolt. It is connected via a connector 91 to a clamping bolt 89 screwed into a bracket 87 fixed by a connector 85. The bracket 87 has a slide plate 9 that guides and fixes a plurality of vertically extending elevating plates 93.
5 are provided, and each slide plate 95
are vertically locked to prevent them from slipping out of the bracket 87 by appropriate locking means (not shown).

On the other hand, each lifting plate 93 is attached to a bracket 99 via a shaft 97 at its upper part, and this bracket 99 is further fixed to the lifting body 101 with bolts or the like. Further, a plurality of main cylinders 103 are connected to the front plate 1 as shown in FIG.
It is fixed at 1. Then, each piston rod 105 is engaged with the upper surface of the push-up body 101,
The push-up body is always supported by an elastic machine 109 whose one end is supported by a locking member 107 such as a pin provided on the front plate 11 and whose other end is supported by the shaft 97 at the top of the elevating plate 93. 101 and the piston rod 105 of the main cylinder are urged into engagement.

Therefore, the tracking start setting handle 81 and the bracket 87 move up and down together with the lower apron 17 when it goes up and down. Then, as will be described later, when the slide plate 95 is pressed and fixed to the elevating plate 93 via the shaft 83, the connector 91, and the clamping bolt 89 by rotating the tracking start setting handle 81, the elevating plate 93 is also integrated with the lower apron 17. go up and down. Therefore, as the lower apron 17 rises, the elevating plate 93 and the push-up body 101 also rise, and the piston rod 105 of the main cylinder 103 is pressed. The pressure oil compressed by this operation communicates with each of the follower cylinders 61 through a hydraulic circuit, which will be described later, to extend the piston rod 63 of the follower cylinder 61 and rotate the link mechanism 57.

Next, the operation of the workpiece following device having the above configuration will be explained with reference to FIG. 5 and subsequent figures.

In the above embodiment, depending on the size of the lower mold 19, for example, the shoulder 19a of the lower mold 19, that is, the first
The following two slide mechanisms are provided so that the follower arm 23 can move vertically and longitudinally in order to select point A shown in the figure and FIG. 7, which will be described later, as the center of rotation. When the height of the lower mold 19 provided on the upper surface and the height of the follower arm 23 are different, the height of the lower mold 19 and the height of the follower arm 23 are different.
The mold height adjustment handle 39 is rotated so that the height is horizontal, and the following arm 23 is moved and adjusted in the vertical direction via the vertical slide 27. Engagement line of upper mold 7 and lower mold 19 and shoulder 19 of lower mold 19
If the distance (V width) to a (point A) is changed,
The link mechanism 57 is moved and adjusted in the front and rear directions. This movement is performed by moving the side plate 49 back and forth by rotating the V width adjustment handle 51 as described above.

Now, in such a state, when bending the workpiece W as shown in FIG. 7, which will be described later, the lower mold 1
The workpiece W is placed on the upper surface of 9 and the follower arm 23, and pressure oil is supplied to the pressure chamber of the cylinder 13 (for movable lower apron 17) to move lower apron 17.
to rise. At the same time as this lower apron 17 rises, the follower arm 23 also rises together. When the workpiece W comes into contact with the upper die 7 and the upper die 7 further embeds the workpiece W to start bending, the following start setting handle 81 is rotated as described above, and the elevating plate 93 in the detection mechanism 21 is slid. It is pressed and fixed to the plate 95. In this state, when the upper die 7 starts to further embed the workpiece W, that is, when the lower apron 17 rises, the push-up body 101 pushes the main cylinder 1
The piston rod 105 of 03 is pushed in, and the pushed pressure oil is sent to the follower cylinder 61.
In this way, the amount of movement of the lower apron 17 is detected from the start of bending the workpiece.

FIG. 5 shows a hydraulic circuit for this purpose. Each main cylinder 103 and each follower cylinder 61 are connected via an oil passage 111, and the oil compressed by the main cylinder 103 and generated thereby is It flows into the port of the following cylinder 61 via this oil passage 111. Here, the expansion rate of the oil is increased by the area ratio of the follower cylinder 61 and the main cylinder 103. In addition, in FIG. 5, 113 is an oil chamber. Moreover, the above-mentioned hydraulic circuit can have a simple configuration as is clear from the figure.

The pressure oil sent to the follower cylinder 61 as described above causes the piston rod 63 of the follower cylinder 61 to extend, and the rotation shaft 63 shown in FIG.
9, the follower arm 23 is rotated around point A.

Here, as shown in FIG. 7, the upper mold 7 and the lower mold 1
When bending the workpiece W by approaching the workpiece W, the ratio between the amount H ₁ of the plunge from the upper surface of the lower mold 19 into the workpiece W and the amount of following H ₂ at the following point of the following cylinder 61 (distance on line l in the figure) is the shoulder 19a of the lower mold 19 (point A) from the engagement line of the upper mold 7 and the lower mold 19.
Since it is equal to the ratio of the distance B ₁ to the line 1 and the distance B ₂ from this shoulder 19a to the line l, for example, the main cylinder 1
The volume ratio of the following cylinder 61 to that of the H ₂ /
If the setting is the same as H ₁ , the bending of the workpiece W will be followed, and the following arm 23 will reliably move the workpiece W.
Follow and support this.

In this way, the workpiece tracking device is operated in proportion to the amount detected by the detection mechanism 21, that is, the bending depth of the workpiece w, and follows the upward movement, so the conventional detector as described above is not required. It can be done.
Therefore, it is essentially not affected by the deflection of the workpiece W.

For example, the detection mechanism 21 should detect whether the work W is easy to bend or hard to bend, or whether both sides are upright as in box bending or both sides are not upright. The amount of movement of the lower apron 17 corresponding to the predetermined bending depth is independent of the deflection of the workpiece W and can be essentially always the same. Therefore, no error occurs.

In addition, the ratio of the lifting amount of the lower apron 17 to the vertical tracking amount of the tracking arm 23 having the link mechanism 57 etc. provided on the lower apron 17 is determined by the shoulder 1 of the lower die 19.
9a and the following point, and set the following arm to correspond to the amount of movement of the lower apron 17 from the start of bending the workpiece, and to have a following amount of the predetermined ratio as described above to this amount of movement. By configuring the valve 23 to be driven, it is possible to eliminate difficulties in maintaining accuracy and maintenance when using a conventional servo valve or the like.

In addition, as shown in Figure 6, when the dimension of B ₁ above is changed (when the V width is changed), the dimension of B ₂ is B ₂ /B ₁
What is necessary is to change the position of the following cylinder 61 with respect to the longitudinal slide 33 so that the following occurs.

Further, in the above-mentioned ascending type press brake 1, when the lower apron 17 is lowered after the bending process, the elevating plate 93 and the push-up body 101 are also lowered together, and the piston rod 105 of the main cylinder 103 is lowered.
However, the weight of the follower arm 23 causes the piston rod 63 of the follower cylinder 61 to contract, causing the main cylinder 10 to disengage.
No. 3 piston rod 105 is extended. here,
The above-mentioned follow-up start setting position is when the upper die 7 and the workpiece W begin to engage with each other, but in order to perform the next bending after bending the workpiece W, it is necessary to further lower the lower apron 17. Therefore, when the lower apron 17 is further lowered, the piston rod 105 of the main cylinder 103 is fully extended and stops, and the push-up body 101 and the piston rod 105 of the main cylinder 105 are disengaged and separated, stopping at the bottom dead center.

Further, in the above embodiment, the setting of the start of tracking is performed by manually rotating the tracking start setting handle 81, but in addition to this configuration, for example, the pressure increase that occurs when the upper die 7 contacts the workpiece W. It is also possible to detect this electrically using a pressure switch or the like, and to fix the elevating plate 93 to the slide plate 95 using a pressing means such as a cylinder or a rotating means such as a motor.

Furthermore, the present invention can be applied to a type of press brake (descending press brake) in which the upper apron is raised and lowered and the lower apron is fixed.

As understood from the above description of the embodiments, the gist of the present invention is as described in the claims, and the present invention can bring about the following effects.

Since it corresponds to the bending depth of the workpiece, a conventional detector is not required, and it is not affected by the deflection of the workpiece, and its function is fully demonstrated, especially when performing box bending. can be done.

Furthermore, since the detection mechanism can be configured to detect the amount of movement of the movable apron that is unrelated to the deflection of the workpiece, and the drive mechanism can be configured without using conventional servo valves, etc., accuracy can be maintained and Maintenance can be facilitated.

Note that this invention is not limited to the above-mentioned embodiments, and the invention can be implemented in modes other than the above-mentioned embodiments. It does not limit the technical scope.

[Brief explanation of drawings]

1 and 2 are a side view and a plan view of a workpiece following device in a press brake implementing the present invention, and FIG. 3 is a side view of the main parts of the drive mechanism.
Fig. 4 is a front view of the main parts of the detection mechanism, Fig. 5 is a hydraulic circuit diagram, Fig. 6 is an explanatory diagram illustrating changing the V width of the lower die, and Fig. 7 is an explanatory diagram illustrating bending of the workpiece. It is a diagram. Explanation of main symbols shown in the drawings, 1...
Press brake, 17...Movable apron, 21...
...Detection mechanism, W...Workpiece, 23...Following arm, 25...Driving mechanism.

Claims (1)

[Scope of Claims] 1. A detection mechanism 21 that is a device that follows the bounce of a workpiece to be bent in a press brake and detects the amount of movement of a movable apron 17 in the press brake 1, and a workpiece W to be bent. a link mechanism 57 that supports the follow-up arm 23 that follows and supports the spring-up portion of the press brake 1 so as to rotate upwardly around the lower die 19 of the press brake 1; a drive mechanism 25 that drives the link mechanism 57; and a drive mechanism 25 that drives the link mechanism 57; A workpiece following device for a breath brake, comprising: an actuating device that operates the drive mechanism 25 in a proportional relationship to a detected amount.