JP3614612B2 - Reversing device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a reversing device for reversing the workpiece by 180 degrees while moving the workpiece by a predetermined distance along a linear locus in a transfer press device, a transfer machine, and the like.
[0002]
[Prior art]
In the transfer press apparatus, workpieces are sequentially transferred between the processing stations, and operations such as trimming, bending, or drilling are performed for each processing station. Similarly, in the transfer machine, workpieces are sequentially transferred between the respective processing stations, and operations such as drilling, welding, and component mounting are performed at each processing station.
In this type of apparatus, after a workpiece is processed from one side, it may be processed from the opposite side to the workpiece at the next station. In this case, a reversing device for reversing the workpiece is provided between the processing stations.
[0003]
As a conventional example of the reversing device, a rack extending along a linear trajectory of a work is provided, and a pinion gear fixed around a reversing shaft is provided at a work holding portion for holding the work, and the pinion gear and the rack are provided. There are things that are engaged. In this reversing device, the pinion gear rolls on the rack while the work holding part moves along a linear locus, and as a result, the work holding part reverses 180 degrees.
However, in the reversing device using the rack and pinion gear described above, the occurrence of backlash at the meshing portion cannot be completely eliminated, so the work angle after the work is reversed is unstable, and the machining station There is a problem in that the workpiece cannot be positioned accurately.
[0004]
FIG. 4 is a partial front view showing a cam-type reversing device capable of preventing the occurrence of backlash such as meshing of the rack and the pinion gear.
In FIG. 4, Sa and Sb are respective processing stations. A workpiece holder (not shown) is held by the reversing shaft 1, and the reversing shaft 1 reciprocates along the linear trajectory TT between the processing station Sa and the processing station Sb. By this reciprocation, the workpiece is sequentially transferred from the one processing station Sa to the other processing station Sb.
[0005]
A cam arm 2 is fixed to the reversing shaft 1, and an egg-shaped sliding cam 3 is integrally formed on the cam arm 2. A guide block 4 is fixed on a linear trajectory TT along which the reversing shaft 1 moves. A substantially inverted V-shaped guide groove 5 is formed in the guide block 4.
While the reversing shaft 1 moves in the right direction in the figure along the straight line trajectory TT, the sliding cam 3 slides in the guide groove 5, and the reversing shaft 1 moves from the processing station Sa to the processing station Sb. In the meantime, the reversing shaft 1 is reversed 180 degrees counterclockwise, and the direction of the workpiece is changed 180 degrees between the machining station Sa and the machining station Sb.
[0006]
[Problems to be solved by the invention]
In the cam type reversing device shown in FIG. 4, since the reversing shaft 1 is reversed while the sliding cam 3 slides on the guide groove 5, the shapes and dimensions of the sliding cam 3 and the guide groove 5 are set optimally. By doing so, it is possible to eliminate backlash when the reversing shaft 1 is reversed, or to minimize backlash.
However, in the cam type reversing device as shown in FIG. 4, it is difficult to increase the speed of the reversing shaft 1 at the moment when the sliding cam 3 enters the center convex portion 5 a of the guide groove 5. It is difficult to increase the average speed of the shaft 1 from the processing station Sa to the processing station Sb. Therefore, there is a drawback that the number of work processes per unit time cannot be increased.
[0007]
SUMMARY OF THE INVENTION The present invention solves the above-described conventional problems, and an object of the present invention is to provide a reversing device that has a small backlash when reversing a workpiece and can perform a transfer operation at a high speed.
[0008]
[Means for Solving the Problems]
The present invention provides a reversing device that reverses the work holding unit while the work holding unit moves a predetermined distance along a linear trajectory, and is equiangularly spaced on a circumference around the reversal axis of the work holding unit. A plurality of arranged followers and a first one that rotates the work holding part in one direction around the reversing axis by guiding any one of the followers while the work holding part moves along the linear locus. And a second cam that guides a follower different from the follower when the work holding portion rotates in the one direction, and prevents backlash in the direction opposite to the direction of the work holding portion. And a cam.
[0009]
For example, in the first cam and the second cam, a recess that sequentially guides followers arranged on the circumference while the work holding portion moves along the linear locus follows the linear locus. Thus, they are provided with a certain interval. That is, the first cam and the second cam can be constituted by a flat cam extending along the linear locus.
[0010]
In the above, a first set of followers and a second set of followers provided at positions shifted from each other along the reversal axis, the first set of followers being guided by the first cam, Preferably, the second set of followers is guided by the second cam.
[0011]
For example, a rotating body that rotates together with the work holding portion around the reversing axis is provided, and a first set of followers is provided on one surface of the rotating body, and a second set of followers is provided on the other surface. The first cam and the second cam for guiding each set of followers are arranged on the same side with respect to the linear locus.
[0012]
However, two rotating bodies that rotate together with the reversing shaft are provided, and a first set of followers is provided on one rotating body, and a second set of followers is provided on the other rotating body. Is possible.
[0013]
When two sets of followers are provided as described above, the first set of followers are provided at equiangular intervals along the circumference, and the second set of followers is between the first set of followers. Similarly, the first set of followers and the second set of followers are arranged at equal angular intervals in the circumferential direction.
[0014]
The follower is a follower roller using a roller such as a bearing, and the follower roller may be configured to roll to a first cam and a second cam, or the follower may be a columnar shape or the like. This non-rotating member may have a structure in which the follower slides on the first cam and the second cam.
[0015]
In the present invention, followers are arranged at equal angles on the circumference around the reversing axis, and the arrangement of the followers is different from that of the sliding cam 3 shown in FIG. While the reversing shaft moves along the linear trajectory between the processing stations, one of the followers is guided by the first cam, and the reversing shaft and the work holding portion rotate in one direction. When the follower is guided to the first cam, another follower positioned next to the follower along the rotation direction on the circumference around the reversal axis is guided to the second cam, With this second cam, the follower is restrained from the side opposite to the reversing direction, and the work holding part is restrained so that backlash in the direction opposite to the rotating direction does not occur.
[0016]
Therefore, backlash does not occur between the workpiece holding portion and each cam, or backlash is minimized, and the inverted workpiece can be reliably positioned at the processing station. That is, in the present invention, for example, when the first set of followers is guided by the first cam, each follower is guided so that the second set of followers is always guided by the second set of cams. The first cam and the second cam are configured to always constrain the work holding portion from opposite directions of rotation.
[0017]
In addition, the follower is arranged at an equal angle on the circumference around the reversing axis, and this follower rolls in turn to the cam, so when the reversing axis moves along a linear locus There is a one-to-one correspondence between the speed and acceleration and the reversing speed and reversing acceleration of the work holding part, and the moving speed of the sliding cam always changes with respect to the moving speed of the reversing shaft as in the conventional example shown in FIG. It is different. Accordingly, it is possible to increase the moving speed of the reversing axis along the linear locus.
[0018]
In addition, since the first cam and the second cam can be constituted by flat cams along a linear locus, for example, by providing both cams on the same side with respect to the linear locus, the follower can be connected to the first cam and the second cam. The operation of rotating the cam in sequence is smooth, and the reversing operation of the work holding part is smooth. Further, since the reversing axis of the work holding part moves along a linear locus, no wasteful movement occurs in the reversing operation of the work holding part.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a plan view of a reversing device according to the present invention, FIG. 2 is a front view of the reversing device shown in FIG. 1 as viewed in the direction of arrow II, and FIG. is there.
This reversing device is provided, for example, between the first processing station S1 and the second processing station S2 of the transfer press device. The workpiece W is a sheet metal processed product such as a shield case of a magnetic head, for example.
[0020]
In this transfer press apparatus, a number of other processing stations are arranged at predetermined intervals on the upstream side of the first processing station S1 and on the downstream side of the second processing station S2 along the linear trajectory TT. The workpieces are transferred in the X direction between the respective processing stations, and the workpieces W are sequentially delivered to the processing stations arranged in the X direction. At each processing station, punching, drawing, trimming, drilling, and the like from a flat sheet metal are performed. The work W is transferred from the first processing station S1 to the second processing station S2 shown in FIGS. Is delivered 180 degrees while the workpiece is delivered.
[0021]
A symbol A shown in FIG. 1 is a work holding unit. The workpiece holding portions A and A are provided opposite to both sides with the workpiece transfer trajectory Tw-Tw interposed therebetween, and the fingers 11 that hold the workpiece W from both sides are held in the workpiece holding portions A and A, respectively. 11 and finger holders 12 and 12 to which the fingers 11 and 11 are fixed.
In each work holding part A, A, the finger holder 12 is supported by the transfer base 13. The transfer base 13 is guided by a linear guide (not shown) and is driven so as to reciprocate between the first processing station S1 and the second processing station S2 along the linear trajectory TT. Has been.
[0022]
The transfer base 13 is provided with a cam 15 that is driven by a feed bar 14. The finger holder 12 is driven by the cam 15 in the direction in which the workpiece W is held (Y1 direction) and in the direction in which the holding of the workpiece W is released (Y2 direction). At this time, the pair of transfer bases 15 located on both sides of the workpiece transfer locus Tw-Tw reciprocally move in synchronization. That is, when the transfer base 15 stops at the first processing station S1, the finger holder 12 is driven in the Y1 direction, and the workpiece W is held by the fingers 11 and 11 from both sides. When the workpiece W is held, the pair of transfer bases 13 moves to the second processing station S2, and when the transfer base 13 stops at the second processing station S2, the finger holder 12 is moved in the Y2 direction by the cam 15. , The workpiece W is positioned and delivered to the second processing station S2, and predetermined processing is performed.
[0023]
An inversion shaft 16 is fixed to the finger holder 12, and the inversion shaft 16 is rotatably supported by the transfer base 13. The center of rotation of the reversing shaft 16 is indicated by Ow. A reversing shaft is also fixed to the finger holder 12 provided on the side facing the transfer base 13 shown in FIG. 1, and this reversing shaft also rotates to the transfer base 13 on the other side located in the upper part of FIG. It is supported freely.
As shown in FIGS. 1 and 2, a rotating body 20 is fixed to the end of the reversing shaft 16 supported by one transfer base 13 shown in FIG. It rotates together with the finger 11 holding W.
[0024]
A first set of follower rollers 21 is rotatably supported on the surface of the rotating body 20, and the first set of follower rollers 21 has a circumference around the rotation center Ow of the reversing shaft 16. Above, they are arranged at an equiangular interval of 90 degrees. A second set of follower rollers 22 is rotatably supported on the back surface of the rotating body 20. The second set of four follower rollers 22 are arranged at equal angular intervals of 90 degrees on the circumference of the rotation center Ow of the reversing shaft 16. As shown in FIGS. 2 and 3, the first set of four follower rollers 21 and the second set of follower rollers 22 are located on a circumference with a constant radius centered on the rotation center Ow. The first set of follower rollers 21 and the second set of follower rollers 22 are arranged at an angle of 45 degrees with respect to each other on the circumference. As shown in FIG. 1, the first set of four follower rollers 21 and the second set of four follower rollers 22 are arranged in the axial direction of the reversing shaft 16 so as to be spaced from each other. .
[0025]
The follower rollers 21 and 22 are bearings rotatably supported with respect to shafts 21a and 22a fixed to the rotating body 20, or are fitted on the outer periphery of the bearings.
A cam support member 25 is provided between the first processing station S1 and the second processing station S2, and the first cam 26 and the second cam 27 are fixed to the cam support member 25. ing. The first cam 26 and the second cam 27 are provided on one side with respect to the linear locus TT along which the rotation center Ow of the reversing shaft 16 moves, and both the cams 26 and 27 are disposed on the reversing shaft 16. Are disposed at positions shifted from each other in the axial direction. Then, the first set of follower rollers 21 rolls on the first cam 26 and is guided by the first cam 26, and the second set of follower rollers 22 rolls on the second cam 27. And guided to the second cam 27.
[0026]
As shown in FIG. 2 and FIG. 3, the first cam 26 has a concave portion 26a, a convex portion 26b, a concave portion 26c, a convex portion 26d, and a concave portion from the first processing station S1 toward the second processing station S2. 26e are formed in order. Similarly, in the second cam 27, a concave portion 27a, a convex portion 27b, a concave portion 27c, a convex portion 27d, and a concave portion 27e are formed in this order from the first processing station S1 to the second processing station S2. And the 1st cam 26 and the 2nd cam 27 are forming the convex part and the recessed part so that the phase may shift | deviate.
[0027]
Next, the inversion operation of the inversion device of the present invention will be described.
The workpiece W that has been processed at the first processing station S1 is held between the fingers 11 and 11 from both sides. Thereafter, the transfer base 13 is driven in the X direction toward the second processing station S2. Then, the first set of follower rollers 21 provided on the rotating body 20 rolls on the first cam 26, and the second set of follower rollers 22 rolls on the second cam 27. At this time, the first set of follower rollers 21 and the second set of follower rollers 22 always contact the first cam 26 and the second cam 27 at the same time. That is, as shown in FIG. 3, the first set of the follower roller 21 and the second follower roller 22 are restrained by the cams 26 and 27 from opposite directions of rotation, and the rotating body 20 and the work holding unit A are Backlash does not occur.
[0028]
In FIG. 3, the first set of follower rollers 21 are sequentially assigned the signs (1), (3), (5), and (7) in the clockwise direction, and the second set of follower rollers 22 are sequentially indicated. (2), (4), (6), and (8) are attached. In the rotating body 20, the first set of follower rollers 21 and the second set of follower rollers 22 are staggered and arranged at an angle of 45 degrees clockwise (1), (2), (3), (4) They are arranged in the order of ▼, ▲ 5 ▼, ▲ 6 ▼, ▲ 7 ▼, ▲ 8 ▼.
[0029]
When the rotation center Ow of the reversing shaft 16 is located at the first processing station S1, the opening of the work W held by the work holding part A is upward. From this position, the rotational center Ow is accelerated and moved in the X direction along the linear trajectory TT with a predetermined acceleration. In the rotating body 20 stopped at the position (I), the follower roller 21 of {circle around (1)} hits the bottom of the concave portion 26a of the first cam 26 and is restrained from turning clockwise, and at the same time the {circle around (2)} The follower roller 22 hits the convex portion 27b of the second cam 27, and the rotation of the rotating body 20 in the counterclockwise direction is restricted. Therefore, when the rotating body 20 is stopped at the position (I), no backlash occurs in the rotating body 20 and the work holding part A, and the work W that has been processed at the first processing station S1 is: The workpiece 11 is securely held by the fingers 11 of the workpiece holding portion A, and the posture error in the rotation direction does not occur between the workpiece W and the workpiece holding portion A.
[0030]
When the rotation center Ow of the reversing shaft 16 linearly moves in the X direction from the position (I), the follower roller 22 of (2) starts to enter the recess 27c of the second cam 27, and the follower of (1) The roller 21 rolls on the slope of the recess 26 a of the first cam 26. Accordingly, the rotating body 20 rotates counterclockwise. During this time, the follower roller 22 of (2) rolls on the inclined surface reaching the concave portion 27c of the second cam 27 and rotates while the rotating body 20 is restrained counterclockwise, but at the same time (1) The follower roller 21 rolls on the inclined surface of the first cam 26, and the rotating body 20 continues to be restrained in the clockwise direction. Therefore, the rotating body 20 and the work holding part A move while rotating counterclockwise without causing backlash.
When the rotation center Ow of the reversing shaft 16 reaches the middle point (II) between the processing stations S1 and S2, the follower roller (2) and the follower roller (3) are respectively in the recess 26c of the first cam 26. The bottom and the bottom of the concave portion 27c of the second cam 27 are reached. Even at this stage, the rotating body 20 is restrained clockwise and counterclockwise, and backlash does not occur.
[0031]
When the rotation center Ow of the reversing shaft 16 reaches the second processing station Ow and reaches the position (III), the work holding part A rotates 180 degrees, and the work W is in a posture in which the opening part faces downward. . At this time, the follower roller (4) hits the concave portion 27e of the second cam 27, and the follower roller (3) hits the convex portion 26d of the first cam 26, so that the rotating body 20 rotates counterclockwise and clockwise. The workpiece W is restrained in the direction and stopped without causing backlash. Therefore, the workpiece W is stopped at the second processing station S2 with its angular posture positioned with high accuracy. At this time, the workpiece W is placed in the second processing station S2.
[0032]
When the workpiece W is installed in the second machining station S2, the cam 15 is driven by the feed bar 14, the finger 11 is driven in the Y2 direction, the holding of the workpiece W is released, and the second machining station S2. A predetermined machining operation is performed.
After the workpiece W is delivered to the second machining station S2, the rotation center Ow of the reversing shaft 16 moves in the anti-X direction and returns to the first machining station S1, during which the rotating body 20 and the workpiece holding part A are moved. By rotating 180 degrees clockwise, the workpiece holding part A can hold the next workpiece W positioned at the first processing station S1.
[0033]
In the embodiment shown in the figure, a first set of follower rollers 21 and a second set of follower rollers 22 are provided on both the front and back sides of one rotating body 20. Two rotating bodies may be provided at intervals in the direction, and a first set of follower rollers may be supported on one rotating body, and a second set of follower rollers may be supported on the other rotating body. .
Alternatively, when the workpiece W is held by the fingers 11 and 11 from both sides, the fingers 11 and 11 or the finger holders 12 and 12 on both sides are connected to each other, and the rotating body is fixed to the one finger holder 12. The first set of follower rollers is supported by the second finger holder 12 and the second set of follower rollers is supported by the rotating body fixed to the other finger holder 12 so that the first set of follower rollers rolls. And the second cam on which the second set of follower rollers rolls may be positioned on both sides of the workpiece W transfer trajectory Tw-Tw.
[0034]
【The invention's effect】
As described above, in the present invention, when the work is reversed between the processing stations, the work holding portion does not have backlash, and the work can be positioned with respect to each processing station with a highly accurate angular posture. . In addition, the follower is arranged on the circumference of a predetermined radius around the reversing axis, and the rotating body rotates with respect to the linear movement of the reversing axis. Is possible.
[Brief description of the drawings]
FIG. 1 is a plan view showing a work reversing device of the present invention,
FIG. 2 is a front view of the work reversing device shown in FIG.
FIG. 3 is an explanatory diagram of the reversing operation of the work reversing device;
FIG. 4 is an operation explanatory diagram of a conventional work reversing device;
[Explanation of symbols]
W Work S1, S2 Processing station 11 Finger 12 Finger holder 13 Transfer base 15 Cam 16 Reverse shaft 20 Rotating body 21 First set of follower rollers 22 Second set of follower rollers 26 First cam 27 Second cam

Claims (4)

In a reversing device that reverses the work holding part while the work holding part moves a predetermined distance along a linear trajectory, a plurality of pieces arranged at equiangular intervals on a circumference around the reversing axis of the work holding part And a first cam for rotating the work holding part in one direction around the reversing axis by guiding any one of the followers while the work holding part moves along the linear locus. A second cam that guides a follower different from the follower to suppress backlash in the direction opposite to the direction of the work holding part when the work holding part rotates in the one direction. A reversing device characterized in that it is provided. The first cam and the second cam have a recess that sequentially guides a follower arranged on the circumference while the work holding portion moves along the linear locus. 2. The reversing device according to claim 1, wherein the reversing device is provided with a constant interval. A first set of followers and a second set of followers provided at positions shifted from each other along the reversal axis, the first set of followers being guided by the first cam, The reversing device according to claim 1 or 2, wherein a set of followers is guided by the second cam. A rotating body that rotates together with the work holding portion around the reversing axis is provided, and a first set of followers is provided on one surface of the rotating body, and a second set of followers is provided on the other surface. The reversing device according to claim 3, wherein the first cam and the second cam for guiding the set of followers are arranged on the same side with respect to the linear locus.

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