JPH0756133Y2 - Pressurizing robot - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a pressure robot in which a pressure cylinder is provided at the tip of a plurality of operating shafts connected in series to press a member to be pressed against a position-fixed member. In particular, the present invention relates to a pressurizing robot in which a pressurizing reaction force applied to a connecting portion of an operating shaft is reduced.

2. Description of the Related Art A plurality of actuating shafts are connected in series and each is rotated by a driving means, and a pressurizing cylinder is disposed on the actuating shaft at the tip to apply a pressure to a position-fixed member. Pressure robots are used, for example, in spot welding devices and clamp devices. The welding apparatus described in JP-A-60-9585 is an example.

By the way, in such a pressurizing robot, since the pressurizing reaction force by the pressurizing cylinder is received by the connecting portion of the operating shaft, the axial rotation having a direction component perpendicular to the pressurizing direction of the pressurizing cylinder is generated. In the connecting portion that rotatably connects the operation shaft, the reaction shaft may rotate the operation shaft, and the pressure applied by the pressurizing cylinder may be insufficient. For this reason, in such a connecting portion, a drive motor having a large torque or other driving means is adopted, or a measure such as increasing the servo gain of the driving means only when the pressurizing cylinder generates a pressing force is taken. Is common.

However, when a large torque driving means is adopted, the robot becomes large and heavy, and when the servo gain of the driving means is temporarily increased, the control is very difficult. There was a problem that it became complicated.

In any of the cases, part of the driving means such as the speed reducer may be damaged by the pressure reaction force.

On the other hand, for example, as in the device disclosed in Japanese Patent Laid-Open No. Sho 60-196276, an electromagnetic brake is provided at the connecting portion to prevent rotation at the connecting portion by braking the electromagnetic brake, or As in the device described in Japanese Laid-Open Patent Publication No. 54-151530, a hydraulic cylinder as a driving means is arranged between the operating shafts in parallel with the connecting portion, and the operating shaft is rotated by controlling the amount of liquid, and at the It is conceivable to prevent the rotation of the actuating shaft due to the pressure reaction force by blocking the relative movement of the cylinder body and the output rod at the rotation position and performing positioning.

However, when an electromagnetic brake is adopted, braking is performed in the vicinity of the connecting portion, so a high-power electromagnetic brake is required to counter the large pressure applied by a spot welder, etc. Therefore, it is difficult to avoid increasing the size and weight of the robot and increasing the cost. On the other hand, when a hydraulic cylinder is adopted, not only is the control accuracy lower than when the operating shaft is rotated by the drive motor and speed reducer, but also when pressure is applied due to the compression of the liquid in the cylinder. Since the piston may be displaced, it is difficult to control the pressurization position with high accuracy. It is difficult to completely remove air from the cylinder, and the air mixes with the liquid in the cylinder.Therefore, when a high pressure reaction force of, for example, several hundred kgf acts, the liquid does not compress to some extent. It is inevitable.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a pressurizing robot that is lightweight and can obtain high pressurizing position accuracy without increasing the size and weight of the robot. It is in.

Means for Solving the Problems In order to achieve the above object, the present invention has a structure in which an operating shaft connected in series is rotated around a rotation center of a connecting portion by a drive motor through a speed reducer, and In a pressurizing robot in which a pressurizing cylinder is disposed on the operating shaft and pressurizes a member to be pressed against a fixed member, (a) the cylinder main body and (b) the cylinder main body is movable in the axial direction. An output rod arranged, and (c) a brake device for fixing the cylinder body and the output rod of the cylinder and the output rod so that they cannot be moved relative to each other at an arbitrary position by a frictional force. It is arranged in parallel with a connecting portion that connects the operating shaft so as to be rotatable about a center line having a component at right angles, and two connecting portions on the cylinder body side and the output rod side are respectively provided. Connection The cylinder body and the output rod are connected to the operating shaft so as to be relatively rotatable about a center line parallel to the rotation center line, and the cylinder body and the output rod are relatively moved in the axial direction as the operating shaft rotates about the connecting portion. And a cylinder with a brake device for positioning the triangular shape having the connecting portion and the connecting portion at the two points as vertices in an undeformable manner by preventing the relative movement in the axial direction by the brake device. And

In such a pressurizing robot, in the pressurizing robot as described above, the connecting portion that connects the operating shaft so as to be rotatable about the center line having a direction component perpendicular to the pressurizing direction of the pressurizing cylinder, in other words, For example, a cylinder with a brake device is installed in parallel with the connecting part where the rotational force is applied to the operating shaft by the pressure reaction force.When the operating shaft is rotated by the drive motor via the speed reducer, the cylinder body and output While the rod and the rod are moved relative to each other in the axial direction, when the rotation of the operating shaft is stopped and the pressurizing cylinder is operated, a brake device that mechanically brakes the friction between the cylinder body and the output rod is used. By preventing relative movement, that is, expansion and contraction of the cylinder with the brake device, the triangular shape with the connecting portion and the two connecting portions as vertices cannot be deformed, and the operating shaft is positioned. Be done. Therefore, the pressurizing reaction force of the pressurizing cylinder can be received by the operating shaft forming the triangular shape and the entire cylinder with the brake device, and the rotation of the operating shaft at the connecting portion is reliably prevented. At the same time, there is no fear that the pressure reaction force concentrates on the connecting portion and the drive motor or the speed reducer as the drive means is damaged.

As described above, in the pressurizing robot of the present invention, since the rotation of the operating shaft is blocked by the cylinder with the brake device, the drive motor and the speed reducer are not likely to be damaged by the pressurizing reaction force. The pressurizing robot can be made smaller, lighter and cheaper than when a large torque drive motor or a large output electromagnetic brake is used.

Further, since the drive motor and the speed reducer are used as the drive means for rotating the operating shaft, higher control accuracy can be obtained as compared with the case where the operating shaft is rotated by the hydraulic cylinder, while mechanical force is generated by the friction force. Since the operating shaft is positioned by a cylinder with a brake device that brakes at the same time, the positional deviation due to the compression of the liquid, which occurs when driving and positioning with a hydraulic cylinder, is eliminated, and the control accuracy of the pressurization position is improved. As significantly improved.

Further, since it is possible to obtain an axial assisting force by supplying pressure air or the like to the cylinder body while the brake device is not operating, for example, the direction in which the operating shaft rotates according to the gravity acting on itself. By supplying pressure air or the like so as to rotate in the opposite direction, or by switching the supply of pressure air or the like so that a turning force in the same direction as the direction of rotation by the drive motor is applied to the operating shaft. , The torque of the drive motor can be reduced,
A drive motor that is smaller in size can be adopted.

Embodiments Hereinafter, some embodiments of the present invention will be described in detail with reference to the drawings.

1 and 2 are a front view and a plan view of the spot welding apparatus 10, respectively. This spot welding equipment 10
Consists of a vertical articulated 5-axis robot,
Five working shafts, namely, a turning shaft 12, a front-rear shaft 14, a vertical shaft 16, an arm turning shaft 18, and a wrist bending shaft 20, which are connected in series (hereinafter, unless otherwise specified, the working shafts 12, 14, 16, 18, 20). The swivel shaft 12 is disposed on the base 22 so as to be rotatable about a substantially vertical center line l ₁ , and the front-rear shaft 14 is rotatable on an upper end of the swivel shaft 12 about a substantially horizontal center line l _2. Is installed in
The vertical shaft 16 is disposed at the front end of the front-rear shaft 14 so as to be rotatable around a center line l ₃ parallel to the center line l _2, and the arm pivot shaft 18 projects first from the front end of the vertical shaft 16. state is rotatably arranged around the center line l ₄ perpendicular to the center line l _3,
The wrist bending shaft 20 has the above-mentioned center line l _{4 at} the tip of the arm turning shaft 18.
It is arranged so as to be rotatable around a center line l ₅ orthogonal to. Further, these operating shafts 12, 14, 16, 18, and 20 are connected to drive motors 24, 26, 2 connected via a reducer (not shown).
8, 30, and 32 are each rotated within a predetermined operating range. In the present embodiment, the drive means for rotating each operating shaft is constituted by including these drive motors 24, 26, 28, 30, 32 and a speed reducer (not shown).

A stud gun 34 for welding is attached to the wrist bending shaft 20 in a posture orthogonal to the center line l ₅ . The stud gun 34 is a reciprocating pressure cylinder 36 having an upper electrode 40 attached to the tip of an output rod 38, and is fixed to the wrist bending shaft 20 at the rear end of the pressure cylinder 36. The upper electrode 40 is connected to a + terminal of a welding transformer (not shown) via a cable 42. The pair of works 44 and 46 to be welded are positioned and placed on the positioning jig 48, respectively.
A lower electrode 50 is fixedly provided at the welding position of 6. The lower electrode 50 is connected via a cable 52 to the negative terminal of the welding transformer. The above work 4
4,46 correspond to members to be pressed.

On the other hand, two air cylinders 54 and 56 with a brake device are arranged between the turning shaft 12 and the vertical shaft 16. These air cylinders 54 and 56 with a brake device have substantially the same structure, and the brake device 6 is attached to the tip end of the cylinder bodies 58 and 60.
2, 64 are integrally assembled so that the output rods 66, 68 can be stopped at an arbitrary position so that they cannot come in and out. The brake device 62 (64) is provided with a front side pressure chamber 72a, 72a by a switching valve 70 as shown in FIG. 3, for example.
Pressure air is supplied to the b from the air source 74, and the pistons 76a, 7
6b is retracted against the urging force of the spring 78, the compressed state of the disc springs 80a, 80b is released, and the inner diameter of the disc springs is expanded, so that the brake shoe 82 for the output rod 66 (68) is released.
Release the crimped state of a and 82b, and then output rod 66 (68)
While allowing free movement of the piston 76a, the switching valve 70 supplies pressurized air from the air source 74 to the rear pressure chamber 84.
76b is moved forward, and the disc springs 80a, 80b are compressed in the axial direction to reduce the inner diameter thereof, so that the brake shoes 82a, 82b are pressed against the output rod 66 (68) and the output rod 66 is frictionally generated. (68) configured to prevent free movement. The details of the brake devices 62 and 64 are disclosed in, for example, Japanese Utility Model Laid-Open No. 59-13731.

One of the air cylinders 54 with a brake device is relatively rotatable around the center line l ₂ to the upper end of the revolving shaft 12 via a bracket 86 provided in the middle of the cylinder body 58,
While mounted for relative rotation about a center line parallel with the rotational centerline l ₃ in other words, the distal end portion 88 of the output rod 66 is parallel to the rotation center line l ₃ in the vertical axis 16 standing It is attached so as to be capable of relative rotation around the pin 90 provided, and is arranged in parallel with the connecting portion 92 of the front-rear shaft 14 and the vertical shaft 16. Therefore, this air cylinder 54 with a brake device
In the state where the output rod 66 is freely moved in and out, the front-rear shaft 14 and the vertical shaft 16 can rotate about the rotation center line l ₃ , but the output rod 66 is prevented from moving in and out by the brake device 62, and the bracket 86 When the distance between the front end portion 88 and the tip portion 88 is constant, the triangular shape having the connecting portion 92 on which the bracket 86, the tip portion 88, and the rotation center line l ₃ are located as an apex is undeformable. And the front-rear shaft 14 at the connecting portion 92.
The relative rotation between the vertical shaft 16 and the vertical shaft 16 is prevented. The triangle X shown by the solid line in FIG. 4 is in this case.

The brake-equipped air cylinder 54 corresponds to a brake-equipped cylinder, and includes the bracket 86 and the tip portion 88.
Corresponds to two connecting portions on the cylinder body 58 side and the output rod 66 side. Further, the protrusion stroke of the output rod 66 is set to a dimension that allows the front-rear shaft 14 and the vertical shaft 16 to relatively rotate within a predetermined operating range.

Further, the other air cylinder 56 with a brake device has a bracket 94 provided at the front end of the cylinder body 60, and a center line parallel to the rotation center lines l ₂ and l ₃ is provided at an intermediate portion of the swivel shaft 12. while mounted for relative rotation, the tip portion 96 of the output Rod 68 is mounted for relative rotation about the pin 98 in parallel to upright the pivot axis l _2, l ₃ in the vertical axis 16 It is arranged in parallel with the connecting portion 100 between the turning shaft 12 and the front-rear shaft 14. Therefore, in a state where the output rod 68 of the air cylinder 56 with the brake device is free to move in and out, the swivel shaft 12 and the front-rear shaft 14 can freely rotate about the rotation center line l _2. Air cylinder
In the state where the relative rotation of the front-rear shaft 14 and the vertical shaft 16 around the rotation center line l ₃ is blocked by the 54, the brake device 64 blocks the output rod 68 from entering and exiting the bracket 94.
When the distance between the end portion 96 and the tip portion 96 is constant, the triangular shape having the connecting portion 100 on which the bracket 94, the tip portion 96, and the rotation center line l ₂ are located as an apex is undeformable. As a result, relative rotation between the pivot shaft 12 and the front-rear shaft 14 at the connecting portion 100 is prevented. The triangle Y shown by the broken line in FIG. 4 is in this case.

The brake-equipped air cylinder 56 corresponds to a brake-equipped cylinder, and includes the bracket 94 and the tip 96.
Corresponds to two connecting portions on the cylinder body 60 side and the output rod 68 side. Further, the protrusion stroke of the output rod 68 is set to such a size that the swivel shaft 12, the front-rear shaft 14, and the vertical shaft 16 can relatively rotate within a predetermined operation range. In addition, such an air cylinder with a brake device 56
Is an output rod of the air cylinder 54 with the brake device.
Only when the entering / exiting of 66 is blocked by the brake device 62, the relative rotation of the pivot shaft 12 and the front-rear shaft 14 in the connecting portion 100 can be blocked.

Further, one end of the energizing bar 102 is attached to the pin 90 to which the output rod 66 of the air cylinder 54 with the brake device is connected so as to be relatively rotatable. This energizing bar 102
At one end of the cable 42 connected to the upper electrode 40
While the other end of the current-carrying bar 102 is axially slidably fitted to a bracket 86 fixed to the cylinder body 58 and connected to the + terminal of the welding transformer. 106 are connected by a cylinder 104. The cylinder 104 always interrupts the connection between the energizing bar 102 and the cable 106 to allow the energizing bar 102 to move relative to the bracket 86, but at least by the air cylinder 54 with a brake device, the front-rear shaft 14 and the vertical shaft 16 are provided.
When the relative movement between the swivel shaft 12, the front-rear shaft 14 and the vertical shaft 16 is blocked by the air cylinders 54, 56 with a brake device, the power is turned on immediately before the welding work. It is driven to connect the bar 102 and the cable 106.

Then, the spot welding apparatus 10 configured as described above
First, in the state where the output rods 66, 68 of the air cylinders 54, 56 with the brake device can freely move in and out, and the connection between the energizing bar 102 and the cable 106 is cut off, each operating shaft, that is, the swivel shaft 12, Front-rear axis 14, Vertical axis 16, Arm pivot axis 18,
By rotating the wrist bending shaft 20 and the wrist bending shaft 20, respectively, the stud gun 34 is positioned right above the predetermined welding position in a posture substantially vertical to the works 44 and 46. Then, in this state, the brake devices 62, 64 of the air cylinders 54, 56 with the brake device are actuated to prevent the output rods 66, 68 from entering and leaving the cylinder bodies 58, 60, and the cylinder 104 causes the energizing bar 102. And the cable 106 are connected.

Next, the upper electrode 40 is projected by the pressure cylinder 36 of the stud gun 34, whereby the pair of workpieces 44 and
46 is pinched with the lower electrode 50. Then, when the welding current is supplied from the welding transformer in that state, the welding current passes from the upper electrode 40 through the works 44, 46 to the lower electrode 5
Flow to 0, and at this time, the works 44 and 46 are welded based on the heat generated by the electric resistance between the works 44 and 46.

Here, the pressure applied by the pressure cylinder 36 is usually several hundred kg.
Depending on the welding conditions such as the plate thickness and material of the workpieces 44 and 46,
In some cases, a pressure of about 700 kgf may be required. Therefore, due to the pressure reaction force, force is applied to the wrist bending shaft 20 and the vertical shaft 16 in the direction opposite to the pressure direction, and the pressure cylinder
Rotational force is applied to the connecting portions 100 and 92 that connect the operating shafts so as to be rotatable about center lines l ₂ and l ₃ that are perpendicular to the pressing direction of 36 (vertical direction in the state of FIG. 1). To be acted upon. That is, the front-rear shaft 14 and the turning shaft 12 are connected to each other by a substantially horizontal rotation center line l ₂
In the connecting portion 100 that is rotatably connected around, a force that rotates the front-rear shaft 14 clockwise to the rotation center line l ₂ is applied, and the front-rear shaft 14 and the vertical shaft 16 are substantially horizontal. in connection portion 92 which is pivotally connected to the around such pivot axis l _3, the force for relatively rotating the upper and lower shaft 16 counterclockwise about the pivot axis l ₃ with respect to the longitudinal axis 14 acts To be made.

Therefore, in the case of the conventional device in which the air cylinders 54 and 56 with the brake device are not attached, the pressure reaction force is concentrated and applied to the connecting portions 92 and 100 thereof,
If the drive torque of the drive motors 26, 28 is insufficient, the front and rear shafts 14,
The vertical shaft 16 may rotate and the pressurizing cylinder 36 may escape upward to cause welding failure, or the welding position may shift. Further, when the drive torque of the drive motors 26, 28 is sufficient, the reduction gear or the like may be damaged by the pressure reaction force.

On the other hand, in the present embodiment, air cylinders 54, 56 with a brake device are provided in parallel with the connecting portions 92, 100, and the brake devices 62, 64 are actuated to prevent the output rods 66, 68 from coming in and out. By doing so, two undeformable triangles X and Y are formed, so that the pressure reaction force is the swivel axis 12, the front-rear axis 14, and the vertical axis that form these triangles X and Y. It is received by the shaft 16 and the air cylinders 54, 56 with the brake device as a whole, rotation of the operating shaft in the connecting portions 92, 100 is prevented, and welding defects due to the escape of the pressurizing cylinder 36 are prevented. , 1
The pressure reaction force is not concentrated on 00, and the speed reducer is not damaged.

The rotation center line l _{5 of} the arm pivot shaft 18 and the wrist bending shaft 20 is also perpendicular to the pressing direction of the pressing cylinder 36, but the pressing direction of the pressing cylinder 36 is from the vertical direction. The inclination angle, that is, the bending angle at the rotation center line l ₅ is relatively small, and a large rotational force is not applied between the arm pivot shaft 18 and the wrist bending shaft 20 due to the pressure reaction force. However, when it is necessary to perform welding work in a posture in which the pressurizing cylinder 36 and the arm turning shaft 18 are largely bent at the wrist bending shaft 20, a cylinder with a brake device that blocks the rotation of the wrist bending shaft 20 should be provided. Is desirable.

Then, when the welding work is completed in this way, the supply of the welding current is stopped, the output rod 38 of the pressurizing cylinder 36 is drawn in, and the pressurization state of the works 44, 46 is released. After that, the operation of the brake devices 62, 64 is released to allow the output rods 66, 68 to move in and out, and the cylinder 1
The connection between the energizing bar 102 and the cable 106 due to 04 is cut off,
In this state, the respective operating shafts 12, 14, 16, 18, 20 are respectively rotated to move the stud gun 34 to another welding position, and the above welding work is repeated.

As described above, the spot welding apparatus 10 of the present embodiment is configured to prevent the rotation of the connecting portions 92, 100 due to the pressure reaction force by the air cylinders 54, 56 with the brake device.
There is no risk that the drive motors 26, 28 and the reducer will be damaged by the pressure reaction force, and the spot welding device 10 is smaller, lighter and cheaper than when a large torque drive motor or a large output electromagnetic brake is adopted. Becomes

Further, since the drive motors 26, 28 and the speed reducer are used as the drive means for rotating the front-rear shaft 14 and the vertical shaft 16, a higher control is required as compared with the case where those operating shafts are rotated by the hydraulic cylinder. While the accuracy can be obtained, the front and rear shafts 14 and the vertical shaft 16 are positioned by the air cylinders 56, 54 with a brake device that mechanically brakes by frictional force. The positional displacement due to the compression of the liquid is eliminated, and the control accuracy of the pressurizing position is significantly improved as a whole.

In addition, the pressurized air is supplied to the cylinder bodies 58, 60 of the air cylinders 54, 56 with the vertical brake device to supply the vertical shaft 16 and the front-rear shaft 1
Although it is possible to assist the rotation of 4, the vertical axis 16
Since it is normally held in a downward posture, its driving does not require that much driving force, and if the rotation of the front-rear shaft 14 is assisted, the load of the drive motor 28 that drives the up-down shaft 16 increases. Not preferable. For this reason, in this embodiment, the compressed air is not supplied to the cylinder bodies 58, 60.

Next, another embodiment of the present invention will be described. In the following embodiments, parts that are substantially the same as those in the first embodiment will be assigned the same reference numerals and explanations thereof will be omitted.

First, in the embodiment shown in the front view of FIG. 5 and the plan view of FIG. 6, the air cylinder 56 with the brake device is arranged between the two side plates 112 and 114 of the turning shaft 12. At the same time, the side plate 11 is provided with a current-carrying bar 116 that connects the cables 42 and 106.
It is mounted on the outside of 2 in parallel with the air cylinder 56 with the brake device, which makes the device compact. In addition, 118 and 120 in FIG. 5 are covers.

In the embodiment shown in the front view of FIG. 7 and the right side view of FIG. 8, the rotation of the connecting portion 100 between the turning shaft 12 and the front-rear shaft 14 is prevented by the air cylinder 122 with a brake device. In addition, the rotation of the connecting portion 92 between the front and rear shafts 14 and the vertical shaft 16 is prevented by the air cylinder with a brake device 124.
The cylinder body 126 is mounted between the two side plates of the pivot shaft 12 so as to be relatively rotatable about a center line parallel to the rotation center line l _2, and the output rod 128 is centered parallel to the rotation center line l _2. It is attached to the front-rear shaft 14 so as to be relatively rotatable around the line. Further, the cylinder body 130 of the air cylinder 124 with a brake device is attached to the swivel shaft 12 so as to be relatively rotatable about a center line parallel to the center lines l ₂ and l _3, and the output rod 13
2 is attached to the vertical shaft 16 so as to be relatively rotatable around a center line parallel to the rotation center lines l ₂ and l ₃ . In this case,
In order to rotate the front-rear shaft 14 and the vertical shaft 16 in a direction opposite to the direction in which the front-rear shaft 14 and the vertical shaft 16 rotate according to gravity acting on the front-rear shaft 14, that is, in the clockwise direction in FIG.
By supplying pressure air to the cylinder bodies 126 and 130 of 124, the output torque of the drive motors 26 and 28 can be reduced. The rotation prevention of the connecting portion 92 by the air cylinder 124 with the brake device functions only when the rotation of the connecting portion 100 is blocked by the air cylinder 122 with the brake device.

On the other hand, a connector 134 is provided between the pivot shaft 12 and the vertical shaft 16.
The two energizing bars 136 and 138, which are connected to each other so as to be rotatable relative to each other about the center line parallel to the rotation center lines l ₂ and l ₃ , are also connected to the rotation center lines l ₂ and l ₃ at both ends thereof. The cables 42 and 106 are connected so as to be rotatable relative to each other about parallel center lines. By doing so, the rotation of the connecting member 134 allows the front-rear shaft 14 and the vertical shaft 16 to rotate, so that the cylinder 104 as in the first embodiment.
Eliminates the need to connect or disconnect the cable 106. FIG. 8 is a view in which the energizing bars 136 and 138 are omitted.

The embodiment shown in the front view of FIG. 9 and the right side view of FIG. 10 is different from the embodiment shown in FIGS. 7 and 8 in that the front-rear shaft 14 has two side plates 140, 142. The air cylinder 122 with a brake device for preventing the rotation of the connecting portion 100 is arranged between them to make it compact. The cylinder body 126 is attached to the side plates 140, 142, and the output rod 128 is provided. Is attached to the pivot 12. In addition, 144 and 146 are covers, and FIG.
It is the figure which omitted 36 and 138.

Although some embodiments of the present invention have been described in detail with reference to the drawings, the present invention can be implemented in other modes.

For example, although the present invention is applied to the spot welding apparatus in all of the above embodiments, the present invention can also be applied to other pressurizing robots such as a clamp apparatus.

Further, in the above embodiment, the air cylinder 5 with the brake device
4,56,122,124 are used, but the cylinder body 58,60,
If pressure air is not supplied to 126 and 130, output rod 6
As long as the 6,68,128,132 can be held movably in the axial direction, the pistons and the like in the cylinder bodies 58,60,126,130 can be omitted.

Further, the brake device 62 (6
4) is just an example, and as long as the movement of the output rod 66 (68) can be stopped at an arbitrary position, a brake device having another configuration can be adopted.

Further, in each of the above-mentioned embodiments, two air cylinders 54 and 56 with a brake device or 122 and 124 are attached, but one or three or more air cylinders may be provided depending on the configuration of the robot.

Further, in the above-mentioned embodiment, the welding current is supplied through the current-carrying bars 102, 116, 136, 138, but it goes without saying that the means for supplying the welding current can be appropriately changed.

Further, although the above-mentioned embodiments are all vertical articulated 5-axis robots, the present invention can be similarly applied to various other pressure robots such as horizontal articulated robots.

Although not illustrated one by one, the present invention can be implemented in various modified and improved modes based on the knowledge of those skilled in the art.

[Brief description of drawings]

FIG. 1 is a partially cutaway front view showing an example in which the present invention is applied to a spot welding apparatus. FIG. 2 is a plan view of the device of FIG. FIG. 3 is a sectional view showing an example of a brake device for an air cylinder with a brake device in the device of FIG. FIG. 4 is a view for explaining the action of the air cylinder with a brake device in the device of FIG. 5th is a front view showing another embodiment of the present invention. FIG. 6 is a plan view of the embodiment of FIG. FIG. 7 is a front view showing still another embodiment of the present invention. FIG. 8 is a right side view with a part of the embodiment of FIG. 7 omitted. FIG. 9 is a front view showing still another embodiment of the present invention. FIG. 10 is a right side view with a part of the embodiment of FIG. 9 omitted. 10: Spot welding device (pressurizing robot) 12,14,16,18,20: Actuating shaft 24,26,28,30,32: Drive motor 36: Pressurizing cylinder 44,46, Work (pressurized member) 50: Lower electrode (fixed position member) 54,56,122,124: Air cylinder with brake device (cylinder with brake device) 58,60,126,130: Cylinder body 62,64: Brake device 66,68,128,132: Output rod 86,94: Bracket (connection) Part) 88,96: Tip part (connecting part) 92,100: Connecting part l ₁ , l ₂ , l ₃ , l ₄ , l ₅ : Rotation center line

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Takanori Nakamura 1 Toyota Town, Toyota City, Aichi Prefecture, Toyota Motor Co., Ltd. (72) Inventor Yoshitaka Sakamoto 1 Toyota Town, Toyota City, Aichi Prefecture, Toyota Motor Co., Ltd. (56) References JP-A 61-216869 (JP, A) JP-A 60-196276 (JP, A) JP-A 54-151530 (JP, A)

Claims (1)

[Scope of utility model registration request] 1. An operating shaft connected in series is rotated by a drive motor around a rotation center of a connecting portion via a speed reducer, and a pressure cylinder is arranged on the operating shaft at the tip end to be applied. In a pressurizing robot for pressurizing a pressure member to a fixed member, a cylinder body, an output rod disposed on the cylinder body so as to be movable in the axial direction, and a cylinder body and an output rod of the cylinder body by friction force. And a brake device that is fixed so that it cannot move relative to any other position, and that connects the operating shaft so as to be rotatable about a center line having a direction component perpendicular to the pressurizing direction of the pressurizing cylinder. And two connecting portions on the side of the cylinder body and on the side of the output rod which are arranged in parallel with each other so as to be relatively rotatable around a center line parallel to the rotation center line of the connecting portion. Connected, said The cylinder body and the output rod are relatively moved in the axial direction in accordance with the rotation of the operating shaft around the coupling part, and the relative movement in the axial direction is blocked by the brake device, so that the coupling part is formed. And a cylinder with a brake device for positioning a triangular shape having the connecting portions at the two locations as vertices so as not to be deformable.