JPS6116574B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a working unit of a working device that performs various operations such as supplying parts to workpieces and inspecting them on an assembly line.

In general, this type of work equipment is, for example,
As described in No. 9358, it is structured as follows. That is, the working device includes a moving table on which a workpiece is placed and moving, and a plurality of working units arranged near the moving table.
Each work unit is designed to work on a workpiece on a moving table, and specifically,
It is designed to perform one of the following: supplying parts to the workpiece, inspecting (for example, checking whether the parts are being supplied to the specified position), caulking and press-fitting the parts with a weak force, supplying and removing the workpieces to the moving table, etc. . In order to carry out such work, each work unit includes a fixed part fixed to another stationary table or the like, and an operating part movably supported by the fixed part. For example, a chuck is attached to the operating part, and by moving the operating part while holding the part by the chuck, the part is transferred to, for example, a workpiece.

However, in the conventional structure, as a mechanism for moving the operating portion, a structure is adopted in which a motor built in the working device is connected to the operating portion via a gear cam mechanism or the like.

In this way, the conventional structure uses a gear cam mechanism as a device to drive the operating parts of each work unit, which has the disadvantage of making the work equipment larger and more complex, resulting in higher costs. .

Furthermore, in the conventional structure, one or two driving shafts (intermediate driving shafts) are driven by a motor via a cam gear, etc., and the driving shafts are connected to a large number of work units via a gear mechanism. . Therefore, the mounting position of each work unit is greatly limited by the position of the drive shaft and the structure of the gear mechanism. For example, it is not possible to install the work unit far away from the drive shaft or extremely close to the drive shaft. Can not. That is, it may become impossible to arrange the work unit at an optimal position taking into account the flow of the workpiece.

Moreover, the gear mechanism connecting the driving shaft and the working unit is bulky, and the mounting positions of the working units are restricted, so the working units cannot be installed close to each other. Therefore, it became impossible to attach a large number (for example, 13) of work units to one work device, and there was also a problem that the work capacity (number of processes) of each work device was low.

A device has already been developed in which a working unit is driven by an air cylinder instead of the motor and cam gear mechanism described above. In that case, there are no restrictions on the mounting position of the working device. However, providing an air cylinder in each work unit itself increases the cost of the equipment. Furthermore, since the air cylinder is bulky, many work units cannot be attached to one work device, resulting in a relatively low work capacity (number of processes).

The present invention attempts to solve the above-mentioned conventional problems by driving a work unit using a Bowden wire. In the working unit, the working unit includes a fixed part forming a frame of the unit, an operating part supported by the fixed part so as to be movable in both forward and reverse directions, and a stopper that restricts the amount of movement of the operating part in both the forward and reverse directions. and a spring that biases the actuating portion in the forward or reverse direction, and the actuating portion has one end of a first Bowden wire that actuates the actuating portion in the forward direction, and a first Bowden wire that actuates the actuating portion in the reverse direction. One end of the two Bowden wires is connected, and a traction mechanism is provided at a position remote from the work unit to which the other ends of the two Bowden wires are connected, and the drive timings of the first and second wires are coincident or approximately equal. Matching wires are grouped into one wire group or a small number of wire groups, each wire group is connected to one traction mechanism, and a spring is provided between each wire traction portion of the traction mechanism and the wire. This will be explained next with reference to the drawings.

In FIG. 1, which is a schematic vertical cross-sectional view of a working device employing a working unit according to the present invention, the lower part of a vertical cylindrical shaft 5 is rotatably supported by a case 2 installed on a foundation 1 via bearings 3 and 4. An annular moving table 6 is fixed to the upper end of the cylindrical shaft 5, and a plurality of workpieces W (only one is shown) are placed on the outer periphery of the table 6 at intervals in the circumferential direction.
A turret 7 is fixed to the cylinder shaft 5 within the case 2, and a cam follower 8 protruding from the turret 7 is engaged with a roller gear cam 10 (or barrel cam, globoidal cam). Reference numeral 11 denotes an electric motor that drives a cam 10 and a wire pulling mechanism 13 (described later) via a chain 12. When the electric motor 11 is operated, the cylinder shaft 5 and table 6 are stopped intermittently due to the action of the cam 10 and the cam follower 8. Rotate. A fixed shaft 15 whose lower end is fixed to the case 2 is disposed within the cylinder shaft 5. The fixed shaft 15 projects above the cylindrical shaft 5, and a circular table 16 having a smaller diameter than the table 6 is fixed to the upper end. A plurality of work units 17 (only one is shown) are arranged on the upper surface of the outer periphery of the circular table 16 at intervals in the circumferential direction.

As shown in FIG. 2, which is an enlarged cross-sectional view of FIG. A plate-shaped bracket 21 extending inward from the end 20 (center side (right side in FIG. 2)) is fastened to the table 16 by bolts 23 inserted through four holes 22. Frame 1
The both sides 25 of the table 16 extend horizontally and parallel to each other at intervals in the circumferential direction of the table 16, and there is a side part between the inner end 20 and the outer end 26 that connect both ends of the both sides 25. Two guide rods 27 parallel to 25
has been erected. Both ends of each guide rod 27 fit into holes in the frame ends 20 and 26, and are fixed by setscrews 24 screwed into threaded holes in the outer end 26. Both guide rods 27 have two pairs (total of four) of bushes 2.
A movable base 30 (operating portion) is slidably fitted through 8 and 29. Both guide rods 27 of movable base 30
A two-stage hole 31 extending from the inner (right side) end face to the center of the movable table is open in the area between them. A two-step outer end of a rod-shaped stripper 32 is fitted into the hole 31 and connected to the movable base 30 by a vertical stop pin 35. In the illustrated state in which the movable base 30 has moved to the innermost side (to the right), the intermediate portion and right end portion of the stripper 32 are formed into cylinders that protrude from the frame end portion 20 toward the center of the table 16, as shown in FIG. It enters the hole 37 of the boss 36. A screw 38 is attached to the inner surface of the end of the hole 37 on the center side of the table 16 (right side in the figure).
A bolt-shaped stopper 40 is screwed into the screw 38 from the center side of the table 16.
A fixing fitting 45 for fixing the outer tube 43 of the Bowden wire 42 (the first Bowden wire for the movable table 30) to the small diameter threaded portion 41 formed at the center side end of the table 16 of the stopper 40.
are screwed together, and a lock nut 4 is attached to the large diameter threaded portion 46.
7 is threadedly engaged with the end face of the boss 36 in a press-contact state. 48 is a hexagonal nut-shaped flange (FIG. 3) formed between the large and small diameter threaded portions 41 and 46. The inner cable 44 of the Bowden wire 42 passes through a hole in the stopper 40, fits into the hole in the stripper 32, and is secured by a screw 50 in the stripper 32. In the illustrated state, the stripper 32 is in contact with the stopper 40.

40a is a bolt-shaped stopper that is screwed into a screw hole in the frame end 26. The stopper 40a has the same structure as the stopper 40, and the stopper 40a
Small diameter threaded portion 4 at the end of the side away from the movable base 30
A fixing metal fitting 45a for fixing an outer tube 43a of a Bowden wire 42a (second Bowden wire to the movable base 30) is screwed onto 1a, and a lock nut 47a is screwed onto the large diameter threaded portion 46a. 48a is a hexagonal nut-shaped flange. The inner cable 44a of the Bowden wire 42a passes through the hole in the stopper 40a, fits into the hole in the movable base 30, and then tightens the set screw 50a (FIG. 3).
Fixed by A vertically extending cylinder 53 is located in the center of the movable table 30, and the cylinder 53 fits into a pair of notches 54 and 54' provided in the movable table 30 and having an arcuate cross section.

In FIG. 3, which shows a cross-section taken from FIG. 2, the cylinder 53 is fixed to the movable base 30 by a snap spring 53a fitted into a groove on the outer peripheral surface and a nut 56 screwed into a screw 55 on the outer periphery of the lower end. A vertical shaft 58 (operating portion) is slidably fitted into the inner periphery of the lower half of the cylinder 53 via a bush 57.
A male thread 61 on the lower half of the stopper 60 is screwed into the thread on the inner surface of the upper end. A pair of slits 62 extending in the longitudinal direction from near the upper end to the middle part of the cylinder 53 are provided at diametrically opposed positions, and a single horizontal screw 63 is inserted through the slit 62 on the right side in the figure. 63 is cylinder 5
an annular stopper 6 disposed between the shaft 58 and the shaft 58;
4 is pressed against the cylinder 53 and fixed. . A screw 65 is screwed into a screw hole in the cylinder 53, and its tip enters a vertical groove 67 on the outer peripheral surface of the shaft 58 to prevent the shaft 58 from rotating. 66 is a lock nut. The shaft 58 has a small diameter hole 72 perpendicular to the upper end surface, and a Bowden wire 73 is inserted into the hole 72.
The tip of the inner cable 74 (the first Bowden wire for the shaft 58) is fitted and the set screw 75
Fixed by The cable 74 passes through the hole in the stopper 60 and is connected to the outer tube 76.
is fixed to the stopper 60 by a fixing fitting 77 that is screwed into the male threaded portion at the upper end of the stopper 60.

A bracket 68 that protrudes outward through a left slit 62 is fastened to the upper end of the shaft 58 with a bolt 69, and an inner Bowden wire 73a (second Bowden wire for the shaft 58) is attached to the tip of the bracket 68. The tip of the cable 74a is fixed by a set screw 70. A bracket 71 is fastened to the middle part of the cylinder 53 at a position directly below a bracket 68 with a bolt 71a, and a bolt-shaped holder 60a is screwed into a screw hole (not shown) at the tip of the bracket 71 from below. It is. Holder 60a is stopper 6
The outer tube 76a of the Bowden wire 73a is fixed to the lower end by a fixing fitting 77a. Although not shown, an air chuck, a magnetic chuck, etc., for example, is attached to the lower end of the shaft 58.

As shown in FIG. 4, which is a partially cutaway enlarged view of the wire pulling mechanism 13 in FIG.
The other ends of the outer tubes 43, 43a of 2a are fixed to bolt-shaped holders 81, 82 by nut-shaped fixing fittings 79, 80, and both holders 81,
82 is screwed into screw holes in vertical plate-shaped frame portions 83, 83a. Both inner cables 4
4 and 44a extend to the right in the figure through holes in the holders 81 and 82, and their tips are fixed to cylindrical holders 84 and 85 that are substantially concentric with the holders 81 and 82. The holders 84, 85 are slidably fitted into holes of horizontal rods 87, 88 perpendicular to the holders 84, 85,
Steps 89, 90 of holders 84, 85 and rod 8
Compression coil springs 91 and 92 are compressed between 7 and 88.

Each of the horizontal rods 87 and 88 has a number of holes spaced apart in the longitudinal direction, and a holder 84 or 85 is slidably fitted into each hole as shown in FIG. Although only one holder 84, 85 is shown in FIG. 4, the other holders 84, 85 (not shown) are also constructed in the same manner as the holders 84, 85 shown, and each has a stepped portion 89. , 90, and compression coil springs 91, 92 are also provided.

As mentioned above, a plurality of work units 17 are provided, and the Bowden wires extending from the operating parts (movable platform and movable shaft) of the work units other than the shown work unit 17 are placed in separate holders 81, 82 in the not shown parts. , 84, 85. Further, the Bowden wires 73, 73a for driving the shaft 58 in FIG.
It is connected to 5. Note that two traction mechanisms 13 are provided, and the Bowden wire that connects to some operating parts (for example, the movable base 30) is connected to a different traction mechanism from the Bowden wire that connects to other operating parts (for example, the shaft 58). You can also.

Both ends of the rods 87 and 88 are rotatably supported by the upper and lower ends of a pair of vertically extending arms 93 (only one of which is shown). An intermediate portion of the arm 93 is rotatably supported on a common shaft 97 parallel to the rods 87 and 88 via a bush 94. Both ends of the shaft 97 are fixed to a pair of vertical plate-like frames 100. A shaft 9 is located near the lower end of the arm 93.
An annular cam follower 106 is fastened by a bolt 105 and a nut parallel to 7. The cam follower 106 is in contact with a plate cam 113 fixed to a driving shaft 112 parallel to the shaft 97. Drive shaft 11
2 is supported by the side frame 100 via bearings. A sprocket 116 is fixed to the shaft 112, and a chain 1 shown in FIG. 1 is attached to the sprocket 116.
2 is on. Note that a return spring (not shown) is connected to the arm 93 to bias the arm 93 in a direction in which the cam follower 106 comes into contact with the cam 113.

Next, the operation will be explained. The arm 93 in FIG. 4 is always in contact with the cam 113, being pulled by a return spring (not shown). Therefore, when the cam 113 shown in FIG. 4 is rotated in the direction of arrow R by the electric motor 11 shown in FIG.
13, the arm 93 rotates around the common axis 9.
7 as the center and the position shown by the solid line and the two-dot chain line 93'
It oscillates between the positions shown.

When the arm 93 is in the position shown by the solid line, the rod 87 and holder 84 are at the farthest position from the holder 81 of the outer tube 43, and the rod 88 and holder 85 are at the position closest to the holder 82 of the outer tube 43a. . Therefore, when the arm 93 is in the position shown by the solid line, the arm 93 is pulling the cable 44 to the maximum extent through the rod 87 and the holder 84, and the rod 88 is
The cable 44a is loosened to the maximum extent through the holder 85.

When the arm 93 is at the position indicated by the two-dot chain line 93', the rod 87 and holder 84 are at the closest position to the holder 81 of the outer tube 43, and the rod 88 and holder 85 are at the position furthest from the holder 82 of the outer tube 43a. It is in the same position. Therefore, when the arm 93 is in the position shown by the two-dot chain line 93', the arm 93 loosens the cable 44 to the maximum extent through the rod 87 and the holder 84, and also loosens the cable 44a through the rod 88 and the holder 85. Stretched to the max.

Of course, when the arm 93 moves from the position shown by the solid line to the position shown by the two-dot chain line, the tensile force exerted on the cable 44 from the arm 93 decreases, and the tensile force exerted from the arm 93 on the cable 44a increases. Also, when the arm 93 moves from the position shown by the two-dot chain line to the position shown by the solid line, the arm 93
The tensile force exerted on cable 44 increases from
The tensile force exerted on cable 44a from arm 93 is reduced.

The cables 74 and 74a in FIG. 3 and other cables are also attached to holders 84 and 85 (not shown).
Due to the action of the arm 93, the cable 44,
The tensile state changes as in the case of 44a.

Then, as described above, when the tensile force on the cable 44 decreases and the tensile force on the cable 44a increases, the movable base 30 is pulled by the cable 44a and moves on the guide rod 27 to the position where it hits the stopper 40a (shaft 58' in FIG. 3). position). At that time, the stop position of the movable base 30 is the stopper 40a.
It can be adjusted by turning and moving the position. Next, when the tension in the cable 44a is reduced and the cable 44 is pulled, the stripper 3
2, the movable base 30 is returned to the position where the stripper 32 abuts the stopper 40 (the illustrated position). At that time, the stop position of the movable base 30 is determined by rotating the stopper 40 so that the stopper 40 is aligned with the hole 37.
It can be adjusted by changing the amount of insertion.

In FIG. 3, when the arm 93 swings to reduce the tension on the cable 74 and pull the cable 74a, the shaft 58 is lowered to a position where the step 79 near the upper end hits the stopper 64. that time,
The stopping position of the shaft 58 can be adjusted by operating the screw 63 and changing the vertical position of the stopper 64. Next, by reducing the tension on cable 74a and pulling cable 74 upward, shaft 58 is returned to the position where the upper end abuts stopper 60 (the position shown). At this time, the stopping position of the shaft 58 can be adjusted by turning the stopper 60 and changing the amount of insertion into the cylinder 53. The operating parts of other working units, not shown, are likewise driven by cables.

The specific work of the above-mentioned work unit 17 is, for example, as follows. In Fig. 3, first the movable base 3
When the shaft 58 is lowered (stroke M ₁ ) with 0 pushed to the outermost position and a part (not shown) in the corresponding position is held by an air chuck attached to the lower end of the shaft 58, the shaft 58 is raised. (M ₂ ), the movable table 30 moves inward (M ₃ ), then the shaft 58 descends (M ₄ ), and the chuck supplies the parts to the workpiece W (Fig. 1), completing the supply. Then, the shaft 58 rises (M ₅ ), the movable table 30 moves outward (M ₆ ), and the same operation is repeated thereafter. Incidentally, if there is no problem in holding and supplying parts, the shaft 58 and the movable base 30 can be operated at the same time. The table 6 in FIG. 1 rotates intermittently so that a new workpiece W stops directly below the work unit 17 in each work cycle mentioned above, and the workpiece W whose work has been completed by the unit 17 is moved to the next work unit. It is sent to the working position (for example, directly below). The above-mentioned parts have previously been conveyed below the shaft 58' by a suitable mechanism.

Next, the wire pulling mechanism 13 will be explained in more detail with reference to FIG. In the state shown in Figure 4,
The arm 93 pulls the cable 44 as much as possible in the direction of the reverse arrow F, and when the cam 113 rotates in the direction of the arrow R from this state, the arm 93 pulls the common shaft 9 due to the contraction force of a return spring (not shown).
7 in the direction of arrow F until it reaches the position 93' from the arm 93 to the rod 87,
The tensile force in the reverse F direction that has been applied to the cable 44 via the spring 91 and the holder 84 is reduced, and the cable 44a is pulled via the holder 85. Then, as explained earlier, the second
As the movable base 30 shown moves outward, the movable base 30 pulls the cable 44 in the direction of arrow F in FIG. 4, and the holder 84 moves in the direction of arrow F to a position 84'. Note that when the tensile force on the cable 44 decreases, the cable 44
1,84', but the cable 44
Since the cable 44 is tensioned by the spring 91 shown in FIG. 4, the cable 44 will not slacken. cam 113
When the arm 93 rotates further, the arm 93 swings in the direction of the reverse arrow F and returns to the position shown by the solid line, and the cable 4
4 is pulled in the direction of the reverse arrow F, the tensile force of the cable 44a decreases, and the movable base 30 in FIG. 2 returns to the position shown.

As described above, the movable base 30 moves in response to the arm 93. In this case, by changing the relative characteristics of the springs 91 and 92, it is possible to adjust the movement timing of the movable base 30 relative to the swing timing of the arm 93. can. That is, even if, for example, a long spring is used as the spring 91 and is greatly compressed in the free state, and the arm 93 starts swinging in the direction of the arrow F from the position shown by the solid line in FIG. 4 and the spring 91 is slightly expanded,
If the repulsive force of the spring 91 is set to be equal to or exceed the repulsive force of the spring 92 (ignoring the frictional force), the movable base 30 will start moving only after the arm 93 has further swung by a predetermined amount. do not. On the contrary, for example, a weak spring is used as the spring 91, and the fourth
When the repulsive force of the spring 91 is made to match the repulsive force of the spring 92 in the state shown in the figure, the movable base 30 also starts moving at the same time as the arm 93 starts swinging in the direction of the arrow F. Also, the arm 93 is indicated by the two-dot chain line 9 in FIG.
3' and the movable base 30 in FIG. 2 is in contact with the stopper 40a, when the repulsive force of the spring 92 exceeds the repulsive force of the spring 91, the arm 93 swings in the reverse F direction. Even if you start
Only by compressing the spring 91, the movable base 30 does not start moving until the arm 93 swings a predetermined amount.
On the contrary, both springs 91 and 92 at the start of tension
If the repulsive forces of the arms 93 and the movable base 30 are made to match, the movement start timings of the arm 93 and the movable base 30 in the reverse F direction will match. In this way, the movement timing of the movable table 30 is determined by the springs 91 and 92.
Similarly, the operating timing of the operating parts of the other working units is adjusted by corresponding springs.

As explained above, according to the present invention, the work unit 17 is driven by the Bowden wires 42, 42a, 73, and 73a, so that the work unit 17 can be driven via a cam mechanism as in the past, or by an air cylinder. Compared to the case where the unit is driven, the structure of the working unit 17 can be simplified and the cost of the device can be reduced. Furthermore, since the work unit 17 can be made smaller, it becomes possible to attach a large number of work units 17 (for example, 13 or more) to one work device, and the work capacity (number of processes) of each work device can be increased. can. The mounting position of the work unit 17 is free, and the work unit 17 can be placed at an optimal position taking into consideration the flow of the work W.

Furthermore, in the present invention, a large number of wires connected to the operating parts (for example, the movable table 30) of the working unit 17 that operate synchronously or approximately synchronously are collectively pulled by one or a small number of arms 93 (pulling parts). Since the tension mechanism is made to be tensioned, the structure of the traction mechanism 13 is simplified, and in this respect as well, the cost of the device can be reduced.

Furthermore, in the present invention, since the springs 91, 92 are provided between the wire pulling portion of the pulling mechanism 13 and the wire 42 (cables 44, 44a), both springs 91,
By appropriately selecting the characteristics of 92, the operating timing of each operating part can be adjusted individually. Therefore, even though a plurality of wires are pulled by a common arm 93, all operating parts can be driven at optimal timing.

Note that when embodying the present invention, the wires 42, 42a and the movable base 30, etc. in FIG. 2 can be eliminated, and the shaft 58 in FIG. , 73a, cylinder 53, etc., and the shaft 58 can be moved only in the horizontal direction. The present invention can also be applied to rotary or chuck type work units.

Furthermore, in the present invention, instead of the cam 113 shown in FIG. 4, a solenoid, an air cylinder, or the like may be used to pull the wire group.
The present invention can also be applied to a working device in which a moving table carrying a workpiece moves linearly while stopping intermittently, and a working device in which a moving table moves continuously. For example, the work unit 17 can be installed radially outward of the movable table 6 in FIG. 1 via another frame.

[Brief explanation of the drawing]

FIG. 1 is a schematic vertical cross-sectional view of a working device employing a working unit according to the present invention, and FIG.
FIG. 3 is a schematic enlarged sectional view of FIG. 2, and FIG. 4 is an enlarged partially cutaway view of FIG. 1. 6... Moving table, 13... Traction mechanism, 17... Working unit, 30, 58... Movable base and shaft (operating part), 40, 40a, 60, 64... Stopper,
42, 42a, 73, 73a... Bowden wire, W... Work.

Claims (1)

[Claims] 1. In a plurality of work units installed near a movable table to perform work on workpieces on the movable table, the work unit has a fixed part forming the frame of the unit, and a fixed part that can be used in both forward and reverse directions. An operating part that is movably supported and a stopper that restricts the amount of movement of the operating part in both forward and reverse directions are provided. The second actuates the part in the opposite direction.
One end of the Bowden wire is connected to the other end of the Bowden wire, and a traction mechanism is provided at a position remote from the work unit to which the other ends of both Bowden wires are connected, and the drive timings of the first and second wires coincide or almost coincide. The present invention is characterized in that the wires are grouped into one or a small number of wire groups, each wire group is connected to one traction mechanism, and a spring is provided between each wire traction portion of the traction mechanism and the wire. work unit.