Coupling device

Abstract

To adjust axial misalignment between a connection rod and an insertion hole while simplifying a fitting structure of the connection rod.SOLUTION: A coupling device for detachably connecting a robot arm (R) to a pallet (P) includes an operation member (6) for moving a plurality of balls (16) supported by a support member (12) in a radial direction. The operation member (6) is configured to be movable in a movement direction of the support member (12) with the movement of the support member (12) in the radial direction.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a connecting device that detachably connects a first block and a second block. [Background technology]

[0002] A conventional coupling device for detachably coupling a first block and a second block is described in Patent Document 1. This conventional technology is configured as follows.

[0003] In a conventional coupling device, a base plate is attached to the side wall of a pallet. A coupling rod protrudes from the base plate and is movable along the surface of the base plate. A through hole is formed in a housing attached to the robot arm, and the coupling rod is inserted into the through hole. Two pins parallel to the axial direction of the coupling rod protrude from the base plate. The pins are inserted into support holes in the housing. This eliminates axial misalignment between the coupling rod and the through hole, enabling a strong coupling between the robot arm and pallet even when an external force acts on the coupling device in a direction intersecting the axis. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2021 / 079749 Brochure Summary of the Invention [Problem to be solved by the invention]

[0005] However, in conventional connecting devices, it is necessary to provide a structure on the base plate that allows the connecting rod to move, which can make the structure for attaching the connecting rod complex.

[0006] An object of one aspect of the present invention is to provide a connecting device that simplifies the mounting structure of the connecting rod and is capable of adjusting the axial misalignment between the connecting rod and the insertion hole. [Means for solving the problem]

[0007] In order to achieve the above object, the present invention provides a coupling device configured as follows, as shown in, for example, FIGS. 1 to 26.

[0008] A coupling device according to one aspect of the present invention is a coupling device that detachably couples a first block R and a second block P, and includes an engagement unit 2 provided in a housing 1 attached to the first block R. The engagement unit 2 includes a cylinder bore 3 formed in the housing 1, an output member 5 that is inserted into the cylinder bore 3 so as to be axially movable, a support member 12 that protrudes from the second block P and has an insertion hole 18 into which a connecting rod 21 that has an engaged portion 21 a formed on its outer peripheral wall is inserted and that is movable in the radial direction of the cylinder bore 3, a plurality of engaging members 16 that are supported by the support member 12 so as to be movably in the radial direction and that are engageable with the engaged portion 21 a of the connecting rod 21 inserted into the insertion hole 18, and an operating member 6 that moves the plurality of engaging members 16 in the radial direction by movement of the output member 5 in the axial direction, and the operating member 6 is movable in the movement direction of the support member 12 in accordance with the radial movement of the support member 12.

[0009] The present invention has the following advantages. Both the support member that supports the engaging member and the operating member that operates the engaging member are movable in the radial direction of the cylinder bore, and as the support member moves, the operating member moves in the direction of movement of the support member. Therefore, even if the axial alignment of the connecting rod and the insertion hole becomes misaligned, the relative positional relationship between the support member and the operating member is maintained, so the driving force of the output member can be transmitted evenly to the connecting rod via each engaging member. This makes it possible to eliminate axial alignment misalignment between the connecting rod and the insertion hole while simplifying the mounting structure of the connecting rod.

[0010] The above-mentioned connecting device preferably has the following configurations (1) to (9).

[0011] (1) The output member 5 may include locking portions 53, 54 that lock the support member 12 or the operating member 6 so that they can move in the radial direction. In this case, the support member or the operating member can be connected to the output member so as to be movable in the radial direction.

[0012] (2) The support member (12) may have a cylindrical portion (13) that forms the insertion hole (18), and a through hole (15) may be formed in the cylindrical wall of the cylindrical portion (13) in the radial direction, and the engaging member (16) may be inserted into the through hole (15). In this case, the driving force of the output member can be transmitted evenly to the connecting rod via the balls inserted into the through holes of the cylindrical portion.

[0013] (3) The operating member 6 may be engaged with the engaging portions 53, 54, and the operating member 6 may move in the axial direction in conjunction with the axial movement of the output member 5, thereby moving the multiple engaging members 16 in the radial direction. In this case, by moving the operating member in the axial direction, the operating member can move the plurality of engaging members in the radial direction.

[0014] (4) The support member 12 is engaged with the engaging portions 53, 54 and is movable in the axial direction in accordance with the movement of the output member 5 in the axial direction, and the operating member 6 is arranged around the support member 12, and the movement of the support member 12 in the axial direction may move the multiple engaging members 16 in the radial direction. In this case, the support member moves in the axial direction, and the operating member can move the plurality of engaging members in the radial direction.

[0015] (5) The connecting device may further include at least one support rod 22, 23 protruding from the second block P so as to be parallel to the axial direction of the connecting rod 21, and at least one support hole 19, 20 formed in the housing 1 so as to be parallel to the axial direction of the insertion hole 18, into which the support rod 22, 23 is inserted. In this case, even if there is an error between the pitch dimension between the support rod and the connecting rod and the pitch dimension between the support hole and the insertion hole, the error can be absorbed by the support member having the insertion hole moving radially.

[0016] (6) The coupling device may be configured such that a plurality of the engagement units 2 are provided in the housing 1, and a plurality of the coupling rods 21 corresponding to the plurality of engagement units 2 are protruded from the second block P. In this case, the first block and the second block can be strongly connected by the multiple pairs of connecting rods and engaging units. Furthermore, even if there is an error between the pitch dimension between the connecting rods and the pitch dimension between the insertion holes, the error can be absorbed by the radial movement of the insertion holes.

[0017] (7) The coupling device may have two engagement units 2 provided in the housing 1, one of the engagement units 2 being configured so that the support member 12 can move along a first direction in the radial direction, and the other engagement unit 2 being configured so that the support member 12 can move along a second direction different from the first direction in the radial direction. In this case, compared to a configuration in which, for example, each insertion hole is movable in the same direction, it becomes easier to connect the first block to the second block while maintaining the attitude (tilt) of the second block.

[0018] (8) In the coupling device, the first direction may be a direction in which one and the other of the engagement units 2 are aligned in the radial direction, and the second direction may be a direction perpendicular to the first direction in the radial direction. In this case, it becomes easier to further connect the first block to the second block while maintaining the attitude (tilt) of the second block.

[0019] (9) The connecting device may further include a second engaging unit provided in the housing 1, and the second engaging unit may include a cylinder hole 3 formed in the housing 1, an output member 5 inserted into the cylinder hole 3 so as to be axially movable, a support member 12 protruding from the second block P and having an insertion hole 18 into which a connecting rod 21 is inserted and having an engaged portion 21a formed on its outer wall, the support member 12 being movable in the radial direction of the cylinder hole 3, a plurality of engaging members 16 supported on the support member 12 so as to be movably in the radial direction and engageable with the engaged portion 21a of the connecting rod 21 inserted into the insertion hole 18, and an operating member that moves the plurality of engaging members 16 in the radial direction by moving the output member 5 in the axial direction. In this case, the first block and the second block can be strongly connected by the pair of connecting rods and the engagement unit and the pair of connecting rods and the second engagement unit. Furthermore, even if there is an error between the pitch dimension between the connecting rods and the pitch dimension between the insertion holes, the error can be absorbed by the radial movement of the insertion holes on the engagement unit side. [Effects of the Invention]

[0020] According to one aspect of the present invention, it is possible to provide a connecting device that can eliminate axial misalignment between the connecting rod and the insertion hole while simplifying the mounting structure of the connecting rod. [Brief explanation of the drawings]

[0021] [Figure 1] 1 is a cross-sectional view (planar cross-sectional view) showing an initial state (release state) of a connecting device according to a first embodiment. [Figure 2] FIG. 10 is a cross-sectional view (horizontal cross-sectional view) showing the release state of the coupling device. [Figure 3] FIG. 4 is a cross-sectional view (horizontal cross-sectional view) showing the locking state of the connecting device. [Figure 4] 5A and 5B are cross-sectional views showing examples of the configuration of an output member and an operating member provided in an engagement unit of the coupling device. [Figure 5] 5 is a perspective view showing a state in which the output member and the operation unit 6 shown in FIG. 4 are separated. [Figure 6] 1B-1B in FIG. 1, showing a cross-sectional view of a part of the connecting device as viewed from the front. [Figure 7] 1A is a cross-sectional view taken along the line 1A-1A in FIG. 1, showing a part of the connecting device as viewed from the front. [Figure 8] 3A is a cross-sectional view taken along the line 3A-3A in FIG. 3, showing a part of the connecting device as viewed from the front. [Figure 9] FIG. 2 is a view similar to FIG. 1 showing a first modified example of an engagement unit provided in the connecting device. [Figure 10] FIG. 10 is a view similar to FIG. 1, showing a second modified example of an engagement unit provided in the connecting device. [Figure 11] 10A is a cross-sectional view taken along the line 10A-10A in FIG. 10, and is similar to FIG. [Figure 12] 10B-10B in FIG. 10, and is a cross-sectional view similar to FIG. 6. FIG. [Figure 13] FIG. 10 is a view similar to FIG. 1, showing a third modified example of an engagement unit provided in the connecting device. [Figure 14] 13A is a cross-sectional view taken along the line 13A-13A in FIG. 13, and is similar to FIG. [Figure 15] 13B-13B in FIG. 13, and is a cross-sectional view similar to FIG. 6. FIG. [Figure 16] FIG. 10 is a cross-sectional view (planar cross-sectional view) showing an initial state (release state) of a connecting device according to a second embodiment. [Figure 17] FIG. 10 is a cross-sectional view (horizontal cross-sectional view) showing the release state of the coupling device. [Figure 18] FIG. 4 is a cross-sectional view (horizontal cross-sectional view) showing the locking state of the connecting device. [Figure 19] 18A is a cross-sectional view taken along the line 18A-18A in FIG. 18, showing a part of the connecting device as viewed from the front. [Figure 20] 18B-18B in FIG. 18, showing a cross-sectional view of a part of the connecting device as viewed from the front. [Figure 21] FIG. 2 is a view similar to FIG. 1 showing a first modified example of an engagement unit provided in the connecting device. [Figure 22] 21A is a cross-sectional view taken along the line 21A-21A in FIG. 21, and is similar to FIG. [Figure 23] 21B-21B in FIG. 21, and is the same as FIG. 6. FIG. [Figure 24] FIG. 10 is a view similar to FIG. 1, showing a second modified example of an engagement unit provided in the connecting device. [Figure 25] 24A-24A in FIG. 24, and is a cross-sectional view similar to FIG. [Figure 26] 24B-24B in FIG. 24, and is a cross-sectional view similar to FIG. 6. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0022] [First embodiment] A first embodiment of the present invention will be described below. Note that the following description is an example of a connecting device according to the present invention, and the technical scope of the present invention is not limited to the illustrated example.

[0023] [Structure of the coupling device] Figures 1 to 3 show a first embodiment of the present invention. Figure 1 is a cross-sectional view showing the initial state (disconnected state) of the coupling device of this embodiment. Figure 2 is a cross-sectional view showing the released state of the coupling device, and Figure 3 is a cross-sectional view showing the locked state of the coupling device.

[0024] In this embodiment, a coupling device that couples a robot arm (first block) R, such as an articulated robot, to a pallet (second block) P is exemplified. The coupling device detachably couples the pallet P, on which a workpiece or the like is placed, to the tip of the robot arm R. First, the structure of the coupling device will be described. Note that the left-right direction in the following description refers to the left-right direction in the drawings.

[0025] A housing 1 of the connecting device is attached to the left end (tip) of the robot arm R. The housing 1 is provided with an engagement unit 2 that detachably engages with a connecting rod 21 that protrudes from the pallet P. In this embodiment, the housing 1 is provided with one engagement unit 2.

[0026] The housing 1 includes a main body 1a, a right wall (base end wall) 1b provided on the right side of the main body 1a (the robot arm R side), and a left wall (tip end wall) 1c provided on the left side of the main body 1a (the pallet P side). The main body 1a and the right wall 1b are made of, for example, aluminum, which allows the housing 1 to be lightweight. The left wall 1c is made of, for example, iron, which allows the strength of the left wall 1c on the side where the connecting rod 21 is inserted to be increased.

[0027] The engagement unit 2 includes a cylinder hole 3 formed in the left-right direction within the main body 1a of the housing 1. The cylinder hole 3 includes, from right to left, a large-diameter first cylinder hole (large-diameter hole) 31, a small-diameter second cylinder hole (small-diameter hole) 32 having a diameter smaller than that of the first cylinder hole 31, and a medium-diameter third cylinder hole (medium-diameter hole) 33 having a diameter larger than that of the second cylinder hole 32. An annular protrusion 4 is formed between the second cylinder hole 32 and the third cylinder hole 33, protruding radially inward from the cylinder hole 3. In the illustrated example, the diameter of the second cylinder hole 32 is slightly smaller than that of the third cylinder hole 33, but the diameters of the second cylinder hole 32 and the third cylinder hole 33 may be approximately the same.

[0028] The large diameter portion (piston portion) 51 of the output member 5 is hermetically inserted into the first cylinder bore 31 so as to be movable in the left-right direction (axial direction of the cylinder bore 3). The small diameter portion 52 of the output member 5 is hermetically inserted into the second cylinder bore 32. A locking groove (locking portion) 53 is formed on the left side of the small diameter portion 52, i.e., the side opposite to the large diameter portion 51. An operating member 6 is locked (held) in the locking groove 53 so as to be movable in the radial direction of the cylinder bore 3. The operating member 6 moves left-right in conjunction with the output member 5, and moves multiple balls (engagement members) 16 in the radial direction.

[0029] Fig. 4 is a cross-sectional view showing an example of the configuration of the output member 5 and the operating member 6 provided in the engagement unit 2. Fig. 5 is a perspective view showing a state in which the output member 5 and the operating member 6 shown in Fig. 4 are separated. Fig. 6 is a cross-sectional view taken along the arrow 1B-1B in Fig. 1, showing a part of the coupling device as viewed from the front.

[0030] 4 and 5, the output member 5 has a circular shape in a plan view and includes a large diameter portion 51 and a small diameter portion 52 protruding from the large diameter portion 51. A locking groove 53 for locking the operating member 6 is formed in the radial direction in the small diameter portion 52. In the example shown, the cross section of the locking groove 53 taken along a plane perpendicular to the extension direction of the locking groove 53 has an inverted T shape, and the groove width of the second groove portion 53b located on the bottom side is wider than the groove width of the first groove portion 53a located on the opening side.

[0031] The operating member 6 is disposed in the second cylinder bore 32. The operating member 6 has a cylindrical operating portion 61 with a bottom that abuts against the balls 16. A locking protrusion (locked portion) 62 that is locked into the locking groove 53 of the output member 5 is protruded from the bottom of the operating portion 61. The operating portion 61 has a wedge surface (wedge portion) 17 formed on the inner circumferential surface of its cylindrical wall that widens radially outward toward the tip. The diameter of the operating portion 61 is set slightly smaller than the diameter of the small diameter portion 52 of the output member 5. The locking protrusion 62 has a shape that allows it to be locked into the locking groove 53. In the illustrated example, the cross section of the locking protrusion 62 taken along a plane passing through the central axis of the operating member 6 has an inverted T-shape, and has a first protrusion 62a that is inserted into the first groove 53a and a second protrusion 62b that is inserted into the second groove 53b. The locking projection 62 is slidably inserted into the locking groove 53 from the side of the output member 5. As a result, the output member 5 and the operating member 6 are connected together with the locking projection 62 locked so as not to come out of the locking groove 53.

[0032] As shown in FIG. 1, a first annular gap G1 is formed between the outer peripheral surface of the operating portion 61 and the inner peripheral surface of the second cylinder bore 32. As shown in FIGS. 4 and 6, the output member 5 is oriented such that the extension direction of the locking groove 53 is parallel to the vertical direction, and a second gap G2 is formed between the inner wall surface of the first groove portion 53a and the outer peripheral surface of the first protrusion 62a. Furthermore, a third gap G3 is formed between the inner wall surface of the second groove portion 53b and the outer peripheral surface of the second protrusion 62b. Therefore, the operating member 6 can move in any direction in the radial direction of the cylinder bore 3, i.e., 360 degrees. In this way, the operating member 6 can move left and right in the cylinder bore 3 in conjunction with the output member 5, and can also move in the radial direction of the cylinder bore 3.

[0033] The structure for connecting the output member 5 and the operating member 6 is not limited to the one described above, and any structure may be used as long as it allows the operating member 6 to be connected to the output member 5 so as to be movable in the radial direction.

[0034] A lock chamber 7 is formed on the right side of the output member 5, and a release chamber 8 is formed between the first cylinder bore 31 and the small diameter portion 52 of the output member 5. A supply / discharge passage 9a for supplying and discharging compressed air to the lock chamber 7 is formed in the main body 1a of the housing 1. Another supply / discharge passage 9b for supplying and discharging compressed air to the release chamber 8 is formed in the main body 1a of the housing 1. A mounting hole 10 is formed on the right side of the output member 5, and a retaining spring 11 is mounted in the mounting hole 10. The retaining spring 11 urges the output member 5 leftward against the right wall 1b of the housing 1. The right wall 1b is provided on the main body 1a so as to close the opening on the right side of the cylinder bore 3.

[0035] A guide hole 1d for inserting the connecting rod 21 is formed in the left wall 1c of the housing 1 in the left-right direction. The inner peripheral surface of the guide hole 1d may be tapered to guide the tip of the connecting rod 21. An annular support member 12, into which the connecting rod 21 is inserted through the guide hole 1d, is provided in the third cylinder bore 33. The support member 12 has a cylindrical portion 13 and a flange 14 protruding radially outward from the outer peripheral surface of the left end of the cylindrical portion 13. The flange 14 is sandwiched between the annular protrusion 4 formed on the inner peripheral surface of the cylinder bore 3 and the left wall 1c. This restricts the left-right movement of the support member 12. Four through holes 15 are formed in the cylindrical wall of the cylindrical portion 13 so as to penetrate radially (two of the four through holes 15 are shown in Figures 1 to 3). A ball 16 is inserted into each through hole 15 so as to be movable radially. Furthermore, the wedge surface 17 of the operating member 6 abuts against the ball 16 from the outside in the radial direction, thereby preventing the ball 16 from slipping out of the through hole 15.

[0036] An insertion hole 18 is formed by the cylindrical hole of the cylindrical portion 13. The left end side of the insertion hole 18 communicates with a guide hole 1d in the left wall 1c of the housing 1. A tapered portion 12a is formed on the inner peripheral surface of the left end side of the cylindrical portion 13, and is inclined so that the guide hole 1d and the insertion hole 18 are generally flush with each other.

[0037] 7 is a cross-sectional view taken along the line 1A-1A in FIG. 1, showing a portion of the coupling device as viewed from the front. As shown in FIGS. 1 and 7, an annular fourth gap G4 is formed between the outer peripheral surface of the flange 14 and the inner peripheral surface of the third cylinder bore 33. Furthermore, as shown in FIG. 1, an annular fifth gap G5 is formed between the outer peripheral surface of the cylindrical portion 13 and the inner wall surface of the annular protrusion 4. Therefore, the support member 12 is movable 360 degrees in the radial direction of the cylinder bore 3. Thus, the support member 12 is restricted from moving in the axial direction of the cylinder bore 3, while still being movable in the radial direction of the cylinder bore 3.

[0038] As shown in FIG. 1, the housing 1 is formed with support holes 19 and 20 on both sides of the engagement unit 2 in the horizontal direction (first direction) at a predetermined interval so as to be parallel to the axial direction of the insertion hole 18.

[0039] A connecting rod 21 and two support rods (pins) 22, 23 are provided on the right wall surface of the pallet P so as to protrude to the right (horizontally) and be parallel to each other. The connecting rod 21 can be inserted into the insertion hole 18. Furthermore, the support rod 22 can be inserted into the support hole 19, and the support rod 23 can be inserted into the support hole 20.

[0040] The connecting rod 21 is fixed, for example, by screws, to the right wall surface of the pallet P. An engaged groove (engaged portion) 21a is formed in the circumferential direction on the outer circumferential wall of the connecting rod 21. The engaged groove 21a is configured so that the ball 16 can engage with it.

[0041] The support rods 22, 23 are fixed, for example by screws, to the right wall surface of the pallet P on both sides of the connecting rod 21 so as to be parallel to the axial direction of the connecting rod 21. The protruding length of each of the support rods 22, 23 is set shorter than that of the connecting rod 21. The tip ends of the support rods 22, 23 may be formed in a spherical shape.

[0042] 8 is a cross-sectional view taken along the line 3A-3A in FIG. 3, showing a portion of the coupling device as viewed from the front. The support rod 22 has a cylindrical outer peripheral wall that fits into the support hole 19. In contrast, as shown in FIG. 8, the support rod 23 has projections 23a at the top and bottom of the outer peripheral wall that protrude in the radial direction of the support rod 23, and a relief portion 23b is formed between the two projections 23a. That is, the support rod 23 has projections 23a on both sides of the cylindrical outer peripheral wall in the horizontal direction (first direction) in which the support rods 22 and 23 are aligned, in other words, in the vertical direction (second direction) that intersects (is perpendicular to) the horizontal direction connecting the support rods 22 and 23. The support holes 19 and 20 both have a circular hole shape (cross-sectional shape of the hole). Therefore, even if there is an error between the pitch dimension between support holes 19 and 20 and the pitch dimension between support rods 22 and 23, support rod 23 can move radially (horizontally) within support hole 20. Furthermore, a vertical load acting on pallet P is received by robot arm R via protrusion 23a and support hole 20.

[0043] Instead of providing the protrusions 23a and the relief portions 23b on the outer peripheral wall of the support rod 23, the support rod 23 may be formed in an oval columnar shape with its major axis intersecting (for example, perpendicular to) the direction connecting the support rods 22 and 23. The term "oval" includes an elliptical shape, an oval shape, and an egg shape. An oval columnar shape refers to a columnar shape with an elliptical, oval, or egg-shaped cross section. In this case, the outer peripheral wall of the support rod 22 is formed in a cylindrical shape, as described above. The support holes 19 and 20 also each have a circular hole shape (cross-sectional shape of the hole).

[0044] Furthermore, support rod 23 may be formed in a cylindrical shape like support rod 22, and support hole 20 may be formed as an elongated hole (horizontally elongated hole) with the long axis extending in the direction connecting support hole 19 and support hole 20. In this case, support hole 19 has a circular hole shape (cross-sectional shape of the hole) like the above.

[0045] The connecting device may include a base plate that is attached to the pallet P. In this case, the connecting rod 21 and the support rods 22, 23 may protrude from the base plate and be attached to the right wall surface of the pallet P via the base plate.

[0046] [Operation of the coupling device] The coupling device operates as follows, as shown in Figures 1 to 3.

[0047] 1, the robot arm R and the pallet P are separated. In this initial state, compressed air is discharged from the lock chamber 7 and supplied to the release chamber 8. Therefore, a force pushing rightward (pressing force) corresponding to the pressure of the compressed air in the release chamber 8 acts on the output member 5 against the biasing force of the holding spring 11, moving the output member 5 rightward.

[0048] The robot arm R in the initial state in Figure 1 is moved leftward. As a result, the tip of the connecting rod 21 passes through the guide hole 1d and is inserted into the insertion hole 18 of the support member 12. Also, the tip of the support rod 22 is inserted into the support hole 19, and the support rod 23 is inserted into the support hole 20.

[0049] At this time, if there is an axial misalignment between the axis of connecting rod 21 and the axis of insertion hole 18, the tip of connecting rod 21 will come into contact with tapered portion 12a of support member 12. Then, support member 12 and ball 16 will move together in the radial direction to absorb the axial misalignment. Furthermore, as support member 12 moves in the radial direction, operating member 6 will move via ball 16 in the movement direction of support member 12. In other words, support member 12, ball 16, and operating member 6 will move together in the radial direction of cylinder bore 3. As a result, no axial misalignment will occur between support member 12 and operating member 6, and a relative positional relationship will be maintained in which the axial centers of support member 12 and operating member 6 are aligned.

[0050] Thereafter, the connecting rod 21 is further inserted into the insertion hole 18 and stops at a position where the engaged groove 21a of the connecting rod 21 faces the ball 16. This switches the connecting device from the initial state of FIG. 1 to the release state of FIG. 2.

[0051] Next, when the coupling device is driven to change from the release state shown in FIG. 2 to the locked state shown in FIG. 3, compressed air is discharged from the release chamber 8 and supplied to the lock chamber 7. First, the output member 5 is moved leftward by the combined force of the compressed air pushing the output member 5 leftward from the lock chamber 7 and the leftward biasing force of the retaining spring 11. Next, the wedge surface 17 of the operating member 6 moves the ball 16 radially inward, and the ball 16 abuts against the engaging groove 21 a of the connecting rod 21. At this time, because the axes of the support member 12 and the operating member 6 are aligned, each ball 16 can be pressed evenly by the operating member 6. Subsequently, when the operating member 6 retracts the connecting rod 21 to the right via the ball 16, the right wall surface of the pallet P is pressed against the seating surface 1 e of the left wall 1 c of the housing 1. This switches the coupling device from the release state shown in FIG. 2 to the locked state shown in FIG. 3.

[0052] When the coupling device is driven to release from the locked state of FIG. 3 to the released state of FIG. 2, the compressed air is discharged from the lock chamber 7 and compressed air is supplied to the release chamber 8. Then, first, the force of the compressed air in the release chamber 8 pushing the output member 5 to the right moves the output member 5 to the right against the leftward biasing force of the retaining spring 11. Next, a gap is formed between the wedge surface 17 of the operating member 6 and the ball 16, allowing the ball 16 to move radially outward. This switches the coupling device from the locked state of FIG. 3 to the released state of FIG. 2.

[0053] [Advantages of the coupling device] The coupling device of the above embodiment is a coupling device that detachably couples a robot arm R and a pallet P, and includes an engagement unit 2 provided in a housing 1 attached to the robot arm R. The engagement unit 2 includes a cylinder bore 3 formed in the housing 1, an output member 5 that is inserted into the cylinder bore 3 so as to be axially movable, a support member 12 that protrudes from the pallet P and has an insertion hole 18 into which a connecting rod 21 is inserted, the insertion hole having an engaged groove 21a formed in the outer peripheral wall, and that is movable in the radial direction of the cylinder bore 3, a plurality of balls 16 that are supported by the support member 12 so as to be radially movable and that are engageable with the engaged groove 21a of the connecting rod 21 inserted into the insertion hole 18, and an operation member 6 that moves the plurality of balls 16 in the radial direction by moving the output member 5 in the axial direction. The operation member 6 is movable in the movement direction of the support member 12 in accordance with the radial movement of the support member 12.

[0054] With this configuration, both the support member 12 and the operating member 6 are movable in the radial direction of the cylinder bore 3, and as the support member 12 moves, the operating member 6 moves in the movement direction of the support member 12. Therefore, even if the axial misalignment occurs between the connecting rod 21 and the insertion hole 18, the relative positional relationship between the support member 12 and the operating member 6 can be maintained, and the driving force of the output member 5 can be transmitted evenly to the connecting rod 21 via each ball 16. Therefore, according to this embodiment, it is possible to provide a coupling device that can eliminate the axial misalignment between the connecting rod 21 and the insertion hole 18 while simplifying the mounting structure of the connecting rod 21.

[0055] [Modification of the first embodiment] (First Modification) 9 is a diagram showing a first modified example of the engagement unit 2 of this embodiment, and is a diagram similar to FIG. 1. FIG. 9 shows another structure for connecting the output member 5 and the operating member 6. As shown in FIG. 9, the output member 5 may have a locking protrusion (locking portion) 54 instead of the locking groove 53. Furthermore, the operating member 6 may have a locking hole 63 instead of the locking protrusion 62.

[0056] The locking projection 54 includes, from the left side, a first protrusion 54a and a second protrusion 54b having a smaller diameter than the first protrusion 54a. The locking hole 63 includes, from the left side, a first hole 63a and a second hole 63b having a smaller diameter than the first hole 63a. The first protrusion 54a is inserted into the first hole 63a, and the second protrusion 54b is inserted into the second hole 63b. The locking projection 54 is fixed to the small diameter portion 52, for example, by screws, while inserted into the locking hole 63. In this case, a second gap G2 is formed between the outer circumferential surface of the first protrusion 54a and the inner circumferential surface of the first hole 63a, and a third gap G3 is formed between the outer circumferential surface of the second protrusion 54b and the inner circumferential surface of the second hole 63b. In this manner, the output member 5 and the operating member 6 may be coupled to each other so that the operating member 6 can move in the radial direction of the cylinder bore 3.

[0057] (Second Modification) Fig. 10 is a view showing a second modified example of the engagement unit 2, and is a view similar to Fig. 1. Fig. 11 is a cross-sectional view taken along the line 10A-10A in Fig. 10, and is a view similar to Fig. 7. Fig. 12 is a cross-sectional view taken along the line 10B-10B in Fig. 10, and is a view similar to Fig. 6. Figs. 10 to 12 show only a portion of the coupling device.

[0058] As shown in FIG. 11 , the third cylinder hole 33 of the cylinder hole 3 may be an elongated hole having a major axis in the vertical direction (left-right direction in the figure). The elongated hole is composed of straight and curved portions. In this case, a fourth gap G4 is formed between the third cylinder hole 33 and the support member 12 on both sides of the support member 12 in the vertical direction. With this configuration, the support member 12 is movable only in the vertical direction (second direction) in the radial direction of the cylinder hole 3, and movement in the horizontal direction (first direction) is restricted. In this way, for example, by changing the shape of the third cylinder hole 33, the radial movement direction of the support member 12 can be adjusted. Note that the third cylinder hole 33 may be an elliptical shape composed only of curved lines instead of an elongated hole shape.

[0059] 12, the third gap G3 does not have to be formed between the inner wall surface of the second groove portion 53b and the outer peripheral surface of the second protrusion portion 62b. With this configuration, the support member 12 is only movable in the vertical direction in the radial direction of the cylinder bore 3, and movement in the horizontal direction is restricted.

[0060] Thus, in the present invention, the operation member 6 and the support member 12 being movable in the radial direction means that these members are movable in at least one direction in the radial direction. In other words, the operation member 6 and the support member 12 may be movable in either radial direction, or may be movable in only the horizontal direction (one direction), only the vertical direction (one direction), or both directions (two directions) in the radial direction. (Third Modification) Figure 13 is a diagram showing a third modified example of the engagement unit 2, and is a diagram similar to Figure 1. Figure 14 is a cross-sectional view taken along the line 13A-13A in Figure 13, and is a diagram similar to Figure 7. Figure 15 is a cross-sectional view taken along the line 13B-13B in Figure 13, and is a diagram similar to Figure 6. Figures 13 to 15 show only a portion of the coupling device.

[0061] As shown in FIG. 14, the third cylinder bore 33 of the cylinder bore 3 may be an elongated hole having a major axis in the horizontal direction (the up-down direction in the figure). In this case, a fourth gap G4 is formed between the third cylinder bore 33 and the support member 12 on both sides of the support member 12 in the horizontal direction. With this configuration, the support member 12 is movable only horizontally in the radial direction of the cylinder bore 3, and its movement in the vertical direction is restricted. Also, as shown in FIG. 15, the output member 5 may be arranged so that the extension direction of the locking groove 53 is parallel to the horizontal direction. Furthermore, the first gap G1 does not have to be formed between the inner wall surface of the second groove portion 53b and the outer circumferential surface of the second protrusion portion 62b. With this configuration, the operating member 6 is movable only horizontally in the radial direction of the cylinder bore 3, and its movement in the vertical direction is restricted.

[0062] (Other variations) The coupling device may have a plurality of engagement units 2 provided in the housing 1, and a plurality of coupling rods 21 corresponding to the plurality of engagement units 2 protruding from the pallet P. With this configuration, the robot arm R and the pallet P can be strongly coupled by the plurality of pairs of coupling rods 21 and engagement units 2. Furthermore, even if there is an error between the pitch dimension between each of the coupling rods 21 and the pitch dimension between each of the insertion holes 18, for example, the error can be absorbed by the support members 12, balls 16, and operating member 6 moving together in the radial direction.

[0063] The coupling device may also be configured such that two engagement units 2 are provided in the housing 1, and the support member 12 of one engagement unit 2 is movable along a first radial direction, and the support member 12 of the other engagement unit 2 is movable along a second radial direction different from the first radial direction. With this configuration, it becomes easier to couple the robot arm R to the pallet P while maintaining the orientation (tilt) of the pallet P, compared to, for example, a configuration in which each support member 12 is movable in the same direction.

[0064] Furthermore, the first direction may be a direction in which one and the other engagement units 2 are aligned in the radial direction (for example, a horizontal direction), and the second direction may be a direction perpendicular to the first direction in the radial direction (for example, a vertical direction). This configuration makes it easier to couple the robot arm R to the pallet P while maintaining the attitude (tilt) of the pallet P.

[0065] Furthermore, the coupling device may be provided with the engagement unit 2 and a second engagement unit having a different structure from the engagement unit 2, which is provided in the housing 1. The second engagement unit may have a structure in which the operating member 6 does not move in the radial direction, for example.

[0066] In this case, the coupling device may further include a second engagement unit provided in the housing 1. The second engagement unit includes a cylinder bore 3 formed in the housing 1, an output member 5 inserted into the cylinder bore 3 so as to be axially movable, a support member 12 projecting from the pallet P and having an insertion hole 18 into which a coupling rod 21 having an engaged groove 21a formed in its outer peripheral wall is inserted and movable in the radial direction of the cylinder bore 3, a plurality of balls 16 supported by the support member 12 so as to be radially movable and engageable with the engaged groove 21a of the coupling rod 21 inserted into the insertion hole 18, and an operating member that moves the plurality of balls 16 in the radial direction by axial movement of the output member 5. With this configuration, the pair of coupling rods 21 and the engagement unit 2 and the pair of coupling rods 21 and the second engagement unit can firmly couple the robot arm R and the pallet P.

[0067] Second Embodiment A second embodiment of the present invention will be described below. For ease of explanation, the same reference numerals will be used to designate components having the same functions as those described in the previous embodiment, and the description thereof will not be repeated.

[0068] [Structure of the coupling device] Figures 16 to 18 show a second embodiment of the present invention. Figure 16 is a cross-sectional view showing the initial state of the coupling device of the second embodiment. Figure 17 is a cross-sectional view showing the released state of the coupling device, and Figure 18 is a cross-sectional view showing the locked state of the coupling device.

[0069] Unlike the coupling device of the first embodiment described above, the coupling device of this embodiment is configured such that the engagement unit 2 is in a released state when the output member 5 advances to the left and in a locked state when the output member 5 retreats to the right.

[0070] In the engagement unit 2 of this embodiment, a release chamber 8 is formed on the right side of the output member 5, and a lock chamber 7 (see FIG. 18) is formed between the first cylinder bore 31 and the small diameter portion 52. A bottomed, cylindrical support member 12 including a cylindrical portion 13 that supports a plurality of balls 16 is disposed in the second cylinder bore 32. A locking protrusion 62 protrudes from the bottom of the support member 12. The support member 12 is locked in the locking groove 53 via the locking protrusion 62 so as to be movable in the radial direction, and together with the bolt, it is movable in the left-right direction (axial direction) as the output member 5 moves in the left-right direction.

[0071] Furthermore, a cylindrical operating member 6 is disposed in the third cylinder bore 33. The operating member 6 is disposed surrounding the periphery of the support member 12, restricting movement of the operating member 6 in the axial direction of the cylinder bore 3 while allowing movement in the radial direction of the cylinder bore 3. The operating member 6 is configured such that when the support member 12 moves left and right in conjunction with the output member 5, the wedge surface 17 of the operating member 6 moves the plurality of balls 16 in the radial direction.

[0072] Fig. 19 is a cross-sectional view taken along line 16A-16A in Fig. 16, showing a part of the coupling device as viewed from the front. Fig. 20 is a cross-sectional view taken along line 16B-16B in Fig. 16, showing a part of the coupling device as viewed from the front. Fig. 20 is the same as Fig. 6.

[0073] 16 and 19, an annular fourth gap G4 is formed between the outer peripheral surface of the operating member 6 and the inner peripheral surface of the third cylinder bore 33. Also, as shown in FIG. 16, an annular first gap G1 is formed between the outer peripheral surface of the tubular portion 13 and the inner peripheral surface of the second cylinder bore 32. Furthermore, as shown in FIGS. 16 and 20, a second gap G2 is formed between the inner wall surface of the first groove portion 53a and the outer peripheral surface of the first protrusion 62a, and a third gap G3 is formed between the inner wall surface of the second groove portion 53b and the outer peripheral surface of the second protrusion 62b. Therefore, the operating member 6 and the support member 12 are movable 360 degrees in the radial direction of the cylinder bore 3.

[0074] [Operation of the coupling device] The coupling device operates as follows, as shown in Figures 16 to 18.

[0075] 16, compressed air is discharged from the lock chamber 7 and is supplied to the release chamber 8. Therefore, a pushing force to the left corresponding to the pressure of the compressed air in the release chamber 8 acts on the output member 5 so as to move the output member 5 to the left.

[0076] The robot arm R in the initial state in Figure 16 is moved leftward. As a result, the tip of the connecting rod 21 passes through the guide hole 1d and is inserted into the insertion hole 18 of the support member 12. Also, the tip of the support rod 22 is inserted into the support hole 19, and the support rod 23 is inserted into the support hole 20.

[0077] At this time, if there is an axial misalignment between the axial center of the connecting rod 21 and the axial center of the insertion hole 18, the tip of the connecting rod 21 inserted into the guide hole 1d will come into contact with the support member 12. Then, the support member 12 and the ball 16 will move together in the radial direction to absorb the axial misalignment. Furthermore, as the support member 12 moves in the radial direction, the operating member 6 arranged to surround the periphery of the support member 12 will move in the moving direction of the support member 12. In other words, the support member 12, the ball 16, and the operating member 6 will move together in the radial direction of the cylinder bore 3. As a result, no axial misalignment occurs between the support member 12 and the operating member 6, and the relative positional relationship between the support member 12 and the operating member 6 will be maintained, with their axial centers aligned.

[0078] Thereafter, the connecting rod 21 is further inserted into the insertion hole 18 and stops at a position where the engaged groove 21a of the connecting rod 21 faces the ball 16. This switches the connecting device from the initial state of FIG. 16 to the release state of FIG. 17.

[0079] Next, when the coupling device is driven to change from the release state shown in FIG. 17 to the locked state shown in FIG. 18, compressed air is discharged from the release chamber 8 and compressed air is supplied to the lock chamber 7. The compressed air in the lock chamber 7 then exerts a force pushing the output member 5 rightward, causing the output member 5 to move rightward together with the support member 12. Next, the wedge surface 17 of the operating member 6 moves the ball 16 radially inward, and the ball 16 abuts against the engaging groove 21 a of the connecting rod 21. At this time, because the axes of the support member 12 and the operating member 6 are aligned, each ball 16 can be pressed evenly by the operating member 6. Subsequently, when the operating member 6 retracts the connecting rod 21 rightward via the ball 16, the right wall surface of the pallet P is pressed against the seating surface 1 e of the left wall 1 c of the housing 1. This switches the coupling device from the release state shown in FIG. 17 to the locked state shown in FIG. 18.

[0080] When the coupling device is released from the locked state of FIG. 18 to the released state of FIG. 17, compressed air is discharged from the lock chamber 7 and compressed air is supplied to the release chamber 8. Then, the compressed air in the release chamber 8 first pushes the output member 5 to the left, causing the output member 5 to move leftward. Next, a gap is formed between the wedge surface 17 of the operating member 6 and the ball 16, allowing the ball 16 to move radially outward. This switches the coupling device from the locked state of FIG. 18 to the released state of FIG. 17.

[0081] [Modification of the second embodiment] (First Modification) Figure 21 is a diagram showing a first modified example of the engagement unit 2 of this embodiment, and is a diagram similar to Figure 16. Figure 22 is a cross-sectional view taken along arrows 21A-21A in Figure 21, and is a diagram similar to Figure 19. Figure 23 is a cross-sectional view taken along arrows 21B-21B in Figure 21, and is a diagram similar to Figure 20. Figures 21 to 23 show only a portion of the coupling device.

[0082] As shown in FIG. 22, the third cylinder hole 33 may be an elongated hole having a major axis in the vertical direction (left-right direction in the figure). In this case, a fourth gap G4 is formed between the third cylinder hole 33 and the operating member 6 on both sides of the operating member 6 in the vertical direction. With this configuration, the operating member 6 is movable only in the vertical direction (second direction), and movement in the horizontal direction (first direction) is restricted. In this way, for example, by changing the shape of the third cylinder hole 33, the radial movement direction of the operating member 6 can be adjusted.

[0083] 23, the third gap G3 does not have to be formed between the inner wall surface of the second groove portion 53b and the outer peripheral surface of the second protrusion portion 62b. With this configuration, the support member 12 is only movable in the vertical direction in the radial direction of the cylinder bore 3, and movement in the horizontal direction is restricted.

[0084] (Second Modification) Figure 24 is a diagram showing a second modified example of the engagement unit 2 of this embodiment, and is a diagram similar to Figure 1. Figure 25 is a cross-sectional view taken along the line 24A-24A in Figure 24, and is a diagram similar to Figure 19. Figure 26 is a cross-sectional view taken along the line 24B-24B in Figure 24, and is a diagram similar to Figure 20. Figures 24 to 26 show only a portion of the coupling device.

[0085] 25, the third cylinder hole 33 may be an elongated hole having a long axis in the horizontal direction (the up-down direction in the figure). In this case, a fourth gap G4 is formed between the third cylinder hole 33 and the operating member 6 on both sides in the horizontal direction (first direction) with the operating member 6 sandwiched therebetween. With this configuration, the operating member 6 is movable only in the horizontal direction, and movement in the vertical direction is restricted.

[0086] 26, the output member 5 may be disposed so that the extension direction of the locking groove 53 is parallel to the horizontal direction. Furthermore, the third gap G3 does not have to be formed between the inner wall surface of the second groove portion 53b and the outer peripheral surface of the second protrusion portion 62b. With this configuration, the support member 12 is only movable horizontally in the radial direction of the cylinder bore 3, and movement in the vertical direction is restricted.

[0087] (Other variations) The holding spring 11 attached to the attachment hole 10 is not an essential element and may be omitted.

[0088] The pressure fluid used in the connecting device may be compressed air, or may be a compressed gas other than compressed air, pressure oil, or the like.

[0089] The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. Embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present invention. Furthermore, new technical features can be formed by combining the technical means disclosed in each embodiment. [Explanation of symbols]

[0090] 1: housing, 2: engagement unit, 3: cylinder hole, 5: output member, 6: operating member, 12: support member, 13: cylindrical portion, 15: through hole, 16: ball (engagement member), 18: insertion hole, 21: connecting rod, 21a: engaged groove (engaged portion), 22: support rod, 23: support rod, 53: locking groove (locking portion), 54: locking protrusion (locking portion), P: pallet (second block), R: robot arm (first block)

Claims

1. A coupling device for detachably coupling a first block (R) and a second block (P), The housing (1) is attached to the first block (R) and includes an engagement unit (2) provided in the housing (1). The engagement unit (2) a cylinder hole (3) formed in the housing (1); an output member (5) inserted into the cylinder hole (3) so as to be axially movable; a support member (12) that protrudes from the second block (P) and has an insertion hole (18) into which a connecting rod (21) having an engaged portion (21 a) formed on its outer peripheral wall is inserted, and that is movable in the radial direction of the cylinder hole (3); a plurality of engaging members (16) supported by the support member (12) so as to be movable in the radial direction and engageable with the engaged portions (21 a) of the connecting rods (21) inserted into the insertion holes (18); an operating member (6) that moves the plurality of engagement members (16) in the radial direction by moving the output member (5) in the axial direction; Equipped with The operating member (6) is movable in the direction of movement of the support member (12) in accordance with the radial movement of the support member (12).

2. The coupling device according to claim 1, wherein the output member (5) includes a locking portion (53, 54) that locks the support member (12) or the operating member (6) so as to be movable in the radial direction.

3. The support member (12) has a cylindrical portion (13) that forms the insertion hole (18), and a through hole (15) is formed in the cylindrical wall of the cylindrical portion (13) in the radial direction, 3. The coupling device according to claim 1, wherein the engaging member (16) is inserted into the through hole (15).

4. 3. The coupling device according to claim 2, wherein the operating member (6) is engaged with the locking portions (53, 54), and the operating member (6) moves in the axial direction in conjunction with the axial movement of the output member (5), thereby moving the plurality of engaging members (16) in the radial direction.

5. The support member (12) is engaged with the engaging portions (53, 54) and is movable in the axial direction in accordance with the movement of the output member (5) in the axial direction.

3. The coupling device according to claim 2, wherein the operating member (6) is arranged around the support member (12), and the plurality of engagement members (16) are moved in the radial direction by the support member (12) moving in the axial direction.

6. At least one support rod (22, 23) protruding from the second block (P) so as to be parallel to the axial direction of the connecting rod (21); At least one support hole (19, 20) formed in the housing (1) parallel to the axial direction of the insertion hole (18), into which the support rod (22, 23) is inserted; The coupling device of claim 1 or 2, further comprising:

7. The housing (1) is provided with a plurality of the engagement units (2), 3. The coupling device according to claim 1, wherein a plurality of said coupling rods (21) corresponding to a plurality of said engaging units (2) are protruded from said second block (P).

8. The housing (1) is provided with two of the engagement units (2), In one of the engagement units (2), the support member (12) is movable along a first direction in the radial direction, The coupling device according to claim 7, wherein the other of the engagement units (2) is configured so that the support member (12) is movable along a second direction different from the first direction in the radial direction.

9. the first direction is a direction in which one and the other of the engaging units (2) are aligned in the radial direction; The coupling device according to claim 8 , wherein the second direction is perpendicular to the first direction in the radial direction.

10. Further comprising a second engagement unit provided on the housing (1), The second engagement unit is a cylinder hole (3) formed in the housing (1); an output member (5) inserted into the cylinder hole (3) so as to be axially movable; a support member (12) that protrudes from the second block (P) and has an insertion hole (18) into which a connecting rod (21) having an engaged portion (21 a) formed on its outer peripheral wall is inserted, and that is movable in the radial direction of the cylinder hole (3); a plurality of engaging members (16) supported by the support member (12) so as to be movable in the radial direction and engageable with the engaged portions (21 a) of the connecting rods (21) inserted into the insertion holes (18); an operating member that moves the plurality of engagement members (16) in the radial direction by moving the output member (5) in the axial direction; 3. The coupling device according to claim 1 or 2, comprising:

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