Attachment / detachment device

Abstract

A cam member (66) in a first adapter (20) of an attachment / detachment device (10) has a cam-side engagement surface (72), a first cam surface (78), and a second cam surface (80) on a side surface. The first cam surface (78) is adjacent to the cam-side engagement surface (72) in the displacement direction of a piston (64). The second cam surface (80) is adjacent to the first cam surface (78) in the displacement direction of the piston (64). The intersection angle between the first cam surface (78) and the displacement direction of the piston (64) is defined as a first angle (α). The intersection angle between the second cam surface (80) and the displacement direction of the piston (64) is defined as a second angle (β). The first angle (α) is smaller than the second angle (β).

Description

Detachable device

[0001] The present disclosure relates to a detachment device.

[0002] An example of an attachment / detachment device is an end effector exchange device. The end effector exchange device includes a first adapter provided on a distal arm of a robot and a second adapter to which an end effector is attached. When exchanging an end effector in the robot for another end effector, the second adapter is separated from the first adapter. Then, the second adapter, to which the other end effector has already been attached, is removably connected to the first adapter.

[0003] The first adapter includes a cylinder portion. When the connection between the first adapter and the second adapter is insufficient, a gap is formed between a first end surface of the first adapter facing the second adapter and a second end surface of the second adapter facing the first adapter. In such a case, the cylinder operates to pull the second adapter toward the first adapter, causing the first end surface and the second end surface to abut against each other.

[0004] For this reason, the cylinder unit needs to output a large lift force. The lift force is a force that pulls the second adapter toward the first adapter. International Publication No. 2017 / 212791 describes a configuration in which an auxiliary piston member is connected in series to a main piston member via a rod member, thereby increasing the pressure-receiving area. In this configuration, the cylinder unit can output a large thrust force, resulting in a large lift force.

[0005] In the configuration in which two piston members are arranged in series as described in WO 2017 / 212791, the length of the end effector exchange device in the displacement direction of the piston members increases, which means that the end effector exchange device becomes large.

[0006] The present disclosure aims to solve the above-mentioned problems.

[0007] An aspect of the present disclosure is an attachment / detachment device including a first adapter and a second adapter attachable to and detachable from the first adapter. The first adapter includes a piston driven by supplying and discharging a hydraulic fluid, a cam member integrally connected to the piston, and an engagement ball abutting a side surface of the cam member. When the cam member is in a locked position, the engagement ball protrudes to prevent separation of the first adapter and the second adapter. When the cam member is in an unlocked position, the engagement ball retracts to allow separation of the first adapter and the second adapter.

[0008] The side surface of the cam member has a cam-side engagement surface with which the engagement ball abuts in the locked position and a tapered surface with which the engagement ball abuts in the unlocked position. The tapered surface has a first cam surface adjacent to the cam-side engagement surface in the displacement direction of the piston and a second cam surface adjacent to the first cam surface in the displacement direction of the piston. In the above configuration, a first angle, which is an intersection angle between the first cam surface and the displacement direction of the piston, is smaller than a second angle, which is an intersection angle between the second cam surface and the displacement direction of the piston.

[0009] According to the present disclosure, it is possible to prevent the attachment / detachment device from becoming large in size, and a large lifting force can be obtained in the cylinder portion that includes the piston, the cam member, and the engagement ball.

[0010] The above objects, features and advantages will be easily understood from the following description of the embodiments, which will be described with reference to the accompanying drawings.

[0011] FIG. 1 is a schematic perspective view of an attachment / detachment device according to an embodiment of the present disclosure. FIG. 2 is a cross-sectional view of the attachment / detachment device taken along line II-II in FIG. 1. FIG. 3 is an enlarged view of a main portion of FIG. 2. FIG. 4 is a cross-sectional view of the attachment / detachment device when the connection between the first adapter and the second adapter is insufficient. FIG. 5 is a cross-sectional view of the attachment / detachment device when the engagement ball has moved radially outward from that shown in FIG. 4. FIG. 6 is a cross-sectional view of the attachment / detachment device when the first adapter and the second adapter are in a separable state. FIG. 7 is an enlarged view of a main portion of the attachment / detachment device when the cam member has been displaced upward. FIG. 8 is a cross-sectional view showing a state in which a release operating tool has been inserted into the attachment / detachment device. FIG. 9 is a cross-sectional view showing a state in which the cam member has climbed onto the release operating tool.

[0012] In the following description, "upper" and "lower" refer to the upper and lower directions shown in the drawings, respectively. However, these directions are for convenience in order to simplify the description and make it easier to understand, and are not necessarily the directions when the attachment / detachment device 10 shown in FIG. 1 is actually used.

[0013] 1 is a schematic perspective view of an attachment / detachment device 10 according to this embodiment. In this embodiment, an end effector exchanging device 12 is exemplified as the attachment / detachment device 10. However, the end effector exchanging device 12 is an example of the attachment / detachment device 10. In other words, the attachment / detachment device 10 is not limited to the end effector exchanging device 12.

[0014] The end effector exchange device 12 includes a first adapter 20 and a second adapter 100. The first adapter 20 has a plurality of insertion holes 22 on its upper surface. Bolts (not shown) are inserted into some of the plurality of insertion holes 22. Positioning pins (not shown) are inserted into other several of the plurality of insertion holes 22. The first adapter 20 is attached to, positioned, and fixed to the distal arm AM of the robot RO by these bolts and positioning pins.

[0015] An end effector EC is attached to the second adapter 100. The end effector EC is, for example, a tool, a jig, a chuck, or a gripper. The first adapter 20 has a plurality of insertion holes (not shown) on its underside. Bolts (not shown) are inserted into some of the plurality of insertion holes. Positioning pins (not shown) are inserted into some other of the plurality of insertion holes. The end effector EC is attached to, positioned, and fixed to the second adapter 100 by these bolts and positioning pins.

[0016] Since the above configuration is well known, the distal arm AM and the end effector EC are omitted from the drawings other than Fig. 1. In Fig. 1, the end effector exchange device 12 is in a state in which the first adapter 20 and the second adapter 100 are connected to each other.

[0017] 2 is a cross-sectional view of the end effector exchange device 12 taken along line II-II in FIG. 1. The first adapter 20 includes a first adapter body 24, a clamp base 40, and a cylinder portion 60. The cylinder portion 60 has a cylinder bore 62, a piston 64, a cam member 66, and an engagement ball 82. The cylinder bore 62 is formed as an inner bore in the first adapter body 24. The cylinder bore 62 extends along the axis of the cam member 66. The central axis of the cylinder bore 62 and the central axis of the cam member 66 overlap each other. The cylinder bore 62 opens at the bottom of the first adapter body 24. A recess 25 is formed in the lower end surface of the first adapter body 24, extending diametrically outward from the lower end of the cylinder bore 62.

[0018] The clamp base 40 has a disk portion 42 that fits into the cylinder hole 62, an outer flange portion 44 that extends outward from the lower end of the disk portion 42, and a hollow cylindrical portion 46 that extends downward from the lower end of the outer flange portion 44. The disk portion 42 fits into the lower part of the cylinder hole 62. The outer flange portion 44 fits into the recess 25 of the first adapter body 24. With this fit, the lower end of the cylinder hole 62 is closed by the clamp base 40.

[0019] A piston 64 is inserted into the cylinder bore 62. The piston 64 divides the cylinder bore 62 into a first pressure chamber 30 above the piston 64 and a second pressure chamber 32 below the piston 64. The piston 64 is displaceable up and down in FIG. 2 along the axis of the cylinder bore 62. That is, the displacement direction of the piston 64 coincides with the axial direction of the cylinder bore 62 and also coincides with the axial direction of the cam member 66. For this reason, hereinafter, the "displacement direction of the piston 64" may be referred to as the "axial direction." A piston packing 65 is attached to the circumferential side surface of the piston 64. When the piston 64 displaces, the piston packing 65 comes into sliding contact with the wall surface of the cylinder bore 62.

[0020] 1, the first adapter body 24 has a first port 26 and a second port 28 on its side surface. The first port 26 is a port for supplying and discharging the working fluid to and from a first pressure chamber 30. The second port 28 is a port for supplying and discharging the working fluid to and from a second pressure chamber 32. The working fluid may be, for example, compressed gas or hydraulic oil.

[0021] The first adaptor body 24 further has a plurality of supply ports 34. Pipes (not shown) are connected to each supply port 34. The pipes supply the supply ports 34 with the working fluid required for the end effector EC to operate. The inlets of each supply port 34 are formed on the side surface of the first adaptor body 24. As shown in FIG. 2 , the outlets of each supply port 34 face downward within the first adaptor body 24. An insertion hole 36 is formed in the lower end surface of the first adaptor body 24, and a cylindrical seal member 86 is inserted into the insertion hole 36. The outlets of each supply port 34 communicate with a relay flow path 88 of the cylindrical seal member 86.

[0022] The clamp base 40 has a small diameter hole 50 and a large diameter hole 48 that communicates with the small diameter hole 50. The small diameter hole 50 and the large diameter hole 48 are aligned in the axial direction. The small diameter hole 50 is located above the large diameter hole 48. The lower end of the large diameter hole 48 opens at the lower end of the cylindrical portion 46. The upper end of the small diameter hole 50 opens at the upper end of the disk portion 42. As shown in FIG. 4 , which shows the piston 64 and cam member 66 in a raised position, the cylindrical portion 46 has a notched groove 49 at its lower end. The notched groove 49 extends from the outer peripheral surface to the inner peripheral surface of the cylindrical portion 46.

[0023] As shown in FIG. 2 , the clamp base 40 holds a plurality of engagement balls 82. Specifically, the cylindrical portion 46 has a plurality of retaining holes 52 that penetrate from the outer circumferential surface to the inner circumferential surface. The plurality of engagement balls 82 are disposed in the plurality of retaining holes 52, respectively. The inner diameter of each retaining hole 52 is reduced near the outer circumferential surface of the cylindrical portion 46. This allows the engagement balls 82 disposed in each retaining hole 52 to protrude outward from the cylindrical portion 46 without falling off from the outer circumferential surface of the cylindrical portion 46.

[0024] The cam member 66 is connected to the piston 64 using a screw member 67 and extends downward from the piston 64. The cam member 66 is movable up and down together with the piston 64. The cam member 66 has an upper connecting shaft portion 68 and a lower bulging portion 70 having a larger diameter than the connecting shaft portion 68. The connecting shaft portion 68 is inserted into the small diameter hole 50 of the clamp base 40. The bulging portion 70 is housed in the large diameter hole 48 of the clamp base 40.

[0025] A rod packing 54 is provided on the inner periphery of the disk portion 42 of the clamp base 40. When the cam member 66 is displaced, the rod packing 54 slides relative to the connecting shaft portion 68. A seal member 56 is provided on the outer periphery of the disk portion 42. The seal member 56 abuts against the wall surface of the cylinder hole 62 of the first adapter body 24. The rod packing 54 and the seal member 56 keep the second pressure chamber 32 between the upper surface of the disk portion 42 and the lower surface of the piston 64 airtight from the outside.

[0026] The side of the bulge portion 70 that constitutes the cam member 66 has a cam-side engagement surface 72 and a tapered surface 74 that is adjacent to the cam-side engagement surface 72 in the axial direction. The cam-side engagement surface 72 is the side circumferential surface of the portion of the bulge portion 70 that has a constant diameter. In the illustrated example, the tapered surface 74 is located below the cam-side engagement surface 72. The bulge portion 70 has a stopper portion 76. In the illustrated example, the stopper portion 76 is a large-diameter portion that protrudes slightly diametrically outward above the cam-side engagement surface 72. The side of the stopper portion 76 gradually becomes larger as it extends upward.

[0027] 3 in detail, the tapered surface 74 has a first cam surface 78 and a second cam surface 80. The first cam surface 78 and the second cam surface 80 form the tapered surface 74, the diameter of which tapers downward. In the axial direction, the first cam surface 78 is adjacent to the cam side engagement surface 72, and the second cam surface 80 is adjacent to the first cam surface 78. That is, the first cam surface 78 is located between the cam side engagement surface 72 and the second cam surface 80. In the illustrated example, the first cam surface 78 is located below the cam side engagement surface 72, and the second cam surface 80 is located below the first cam surface 78.

[0028] The intersection angle between the first cam surface 78 and the axial direction (axis L) is defined as a first angle α. The first angle α is half the taper angle of the first cam surface 78. The intersection angle between the second cam surface 80 and the axial direction (axis L) is defined as a second angle β. The second angle β is half the taper angle of the second cam surface 80.

[0029] The first angle α is smaller than the second angle β. That is, the first angle α and the second angle β have a relationship of α<β. The angle difference is calculated by subtracting the first angle α from the second angle β. A preferred example of the angle difference is, for example, 5° to 60°. However, the angle difference is not limited to this range. Furthermore, the first angle α is, for example, 15° to 45°, and the second angle β is, for example, 45° to 75°, but the first angle α and the second angle β are not limited to these ranges. In one aspect, the first angle α and the second angle β are 30° and 50°, respectively.

[0030] As will be described later, when the cam member 66 is in the locked position, the engagement ball 82 abuts against the cam-side engagement surface 72 (see FIG. 2). In contrast, when the cam member 66 is in the unlocked position as shown in FIGS. 4 to 6, the engagement ball 82 abuts against the tapered surface 74 (the first cam surface 78 or the second cam surface 80). The tapered surface 74 forms a retraction space for the engagement ball 82 to move diametrically inward when the second adapter 100 is separated from the first adapter 20.

[0031] As shown in FIG. 2 , the second adapter 100 includes a second adapter body 110 and a clamp plate 120 .

[0032] The second adaptor body 110 has a receiving hole 112 that penetrates in the vertical direction. The upper end of the receiving hole 112 is connected to a recess 114 formed in the upper surface of the second adaptor body 110. The annular clamp plate 120 fits into the recess 114 and is fixed to the second adaptor body 110 via bolts (not shown).

[0033] The second adaptor body 110 has a plurality of delivery ports 118. The inlet of each delivery port 118 is formed on the top surface of the second adaptor body 110 and faces the relay flow path 88 of the cylindrical seal member 86. That is, the delivery port 118 communicates with the supply port 34 via the relay flow path 88. The outlet of each delivery port 118 is formed on the side surface of the second adaptor body 110. Pipes (not shown) are connected to the outlet of each delivery port 118. The working fluid required for operation of the end effector EC is delivered from the delivery port 118 to the pipes.

[0034] The clamp plate 120 has a through hole 122 that penetrates in the vertical direction. An adapter-side engagement surface 124 is formed on the inner periphery of the lower end of the through hole 122. The adapter-side engagement surface 124 is a tapered surface that tapers in diameter from bottom to top.

[0035] When the cam member 66 is in the locked position, the engagement ball 82 abuts against the cam-side engagement surface 72 as described above, and also protrudes toward the clamp base 40 and abuts against the adapter-side engagement surface 124. In this state, the engagement ball 82 is constrained by the cam-side engagement surface 72 and the adapter-side engagement surface 124. Therefore, the engagement ball 82 cannot retract toward the bulge portion 70 of the cam member 66. For this reason, the clamp base 40 cannot move upward relative to the second adapter body 110. For the above reasons, the connection between the first adapter 20 and the second adapter 100 is maintained. In other words, a locked state is established. Hereinafter, the position of the piston 64 when the locked state is established may be referred to as bottom dead center.

[0036] In contrast, when the cam member 66 is in the unlocked position, the engagement ball 82 is released from the constraint of the adapter-side engagement surface 124 and the cam-side engagement surface 72. That is, an unlocked state is established. As shown in FIG. 6 , when the piston 64 is raised to its highest position, the engagement ball 82 can retract until it separates from the adapter-side engagement surface 124 and the cam-side engagement surface 72 and abuts against the second cam surface 80. The engagement ball 82 in the retracted position can pass through the through-hole 122 without interfering with the clamp plate 120. This allows the first adapter 20 to be raised relative to the second adapter 100. This rise allows the first adapter 20 and the second adapter 100 to be separated. Hereinafter, the position of the piston 64 shown in FIG. 6 may be referred to as top dead center.

[0037] As shown in Fig. 1, the second adaptor body 110 has a separation operation hole 130. The separation operation hole 130 opens to the side surface of the second adaptor body 110 and extends to the accommodation hole 112 (see Fig. 2) of the second adaptor body 110. The separation operation hole 130 is formed at a height position corresponding to the notched groove 49 (see Fig. 4) of the cylindrical portion 46 of the clamp base 40.

[0038] As shown in Figure 8, a release operating tool 134 is inserted into the separation operating hole 130 (see Figure 1). The release operating tool 134 is, for example, a release bar 136. When the cam member 66 is in the locked position, inserting the release bar 136 into the second adapter 100 through the separation operating hole 130 causes the tip of the release bar 136 to enter the large diameter hole 48 through the notched groove 49 of the clamp base 40. In this way, the tip of the release bar 136 can be inserted into and removed from the large diameter hole 48 through the notched groove 49. The tip of the release bar 136 also abuts against the second cam surface 80 on the bulge 70 of the cam member 66.

[0039] 1, the first adapter body 24 has a first connector 90, and the second adapter body 110 has a second connector 140. When the first adapter 20 and the second adapter 100 are connected to each other, the first connector 90 and the second connector 140 engage with each other and are electrically connected to each other, thereby forming an electrical path for supplying the necessary power to the end effector EC.

[0040] Next, a description will be given of the operation of attaching and detaching the first adapter 20 and the second adapter 100. In the following, compressed air will be exemplified as the working fluid for attaching and detaching the first adapter 20 and the second adapter 100.

[0041] In the initial state, the first adapter 20 attached to the distal arm AM of the robot RO is separated from the second adapter 100 to which a predetermined end effector EC is attached. Compressed air is supplied to the second pressure chamber 32 through the second port 28, and the piston 64 is stopped at the top dead center as in Figure 4. At this time, the cam member 66 is in the unlock position, and the second cam surface 80 faces the engaging ball 82.

[0042] When connecting the first adapter 20 and the second adapter 100 to each other from the initial state, the distal arm AM of the robot RO is operated appropriately to align the cylindrical portion 46 of the clamp base 40 with the clamp plate 120. Furthermore, the first adapter 20 is moved relatively closer to the second adapter 100, and the cylindrical portion 46 is passed through the through-hole 122 of the clamp plate 120 and inserted into the receiving hole 112 of the second adapter body 110.

[0043] When the cylindrical portion 46 is inserted into the receiving hole 112, the state shown in Fig. 6 is ideally formed. However, as shown in Fig. 4, the lower surface of the first adapter 20 may be separated from the upper surface of the second adapter 100, forming a gap. In this state, the relay flow path 88 and the delivery port 118 are separated from each other, and the first connector 90 and the second connector 140 are separated from each other, so the end effector EC does not operate.

[0044] From this state, the lower surface of the first adapter 20 is brought into contact with the upper surface of the second adapter 100, thereby establishing a locked state. Specifically, compressed air is supplied to the first pressure chamber 30 through the first port 26, and compressed air is discharged from the second pressure chamber 32 through the second port 28. Because the internal pressure of the first pressure chamber 30 becomes greater than the internal pressure of the second pressure chamber 32, the piston 64 and cam member 66 are displaced downward.

[0045] As a result, the engagement ball 82 is pushed by the second cam surface 80 of the bulge 70 and easily moves radially outward along the retaining hole 52. The radially outward direction is the direction toward the clamp plate 120. As a result, as shown in FIG. 5 , the engagement ball 82 moves from the second cam surface 80 to the first cam surface 78. Because the second angle β is greater than the first angle α, the stroke of the piston 64 (the displacement of the cam member 66) until the engagement ball 82 moves from the second cam surface 80 to the first cam surface 78 is relatively small. As the piston 64 and the cam member 66 further move downward, the engagement ball 82 protrudes from the retaining hole 52 and moves closer to the clamp plate 120 while being guided by the first cam surface 78 of the bulge 70 and the adapter-side engagement surface 124.

[0046] This movement of the engaging ball 82 generates a lifting force in the cylinder portion 60 that pulls (lifts) the second adapter 100 toward the first adapter 20. In this embodiment, the first angle α of the first cam surface 78 is smaller than the second angle β of the second cam surface 80. Therefore, by guiding the engaging ball 82 with the first cam surface 78, a larger lifting force can be obtained than when the engaging ball 82 is guided by the second cam surface 80.

[0047] 2, when the piston 64 and cam member 66 are further displaced downward and the piston 64 reaches the bottom dead center, the engagement ball 82 is constrained between the cam-side engagement surface 72 of the bulge portion 70, the lower surface of the stopper portion 76 of the bulge portion 70, and the adapter-side engagement surface 124 of the clamp plate 120. As a result, the engagement ball 82 is tightly sandwiched between the cam member 66 and the clamp plate 120.

[0048] In this way, as the piston 64 reaches the bottom dead center and the cam member 66 enters the locked position, the first adapter 20 and the second adapter 100 are connected via the engaging ball 82, creating a locked state. The distal arm AM (see FIG. 1) then operates appropriately, causing the end effector EC to face the workpiece. The robot RO then performs a predetermined task on the workpiece based on the end effector EC.

[0049] When the end effector EC is to be replaced with another end effector EC, the robot RO operates appropriately to position the distal arm AM at the replacement station, where another second adapter 100 to which another end effector EC has been pre-attached is disposed.

[0050] To separate the second adapter 100 from the first adapter 20, compressed air is supplied to the second pressure chamber 32 through the second port 28, and the compressed air is discharged from the first pressure chamber 30 through the first port 26. Because the internal pressure of the second pressure chamber 32 becomes greater than the internal pressure of the first pressure chamber 30, the piston 64 and the cam member 66 are displaced upward. Accordingly, the cam member 66 moves from the locked position to the unlocked position, and the engagement ball 82 moves away from the cam-side engagement surface 72.

[0051] 6, the piston 64 rises further and reaches the top dead center. At this point, the side surface of the cam member 66 that faces the engagement ball 82 is the second cam surface 80. The engagement ball 82 is able to move diametrically inward until it abuts against the second cam surface 80.

[0052] Next, the distal arm AM operates, causing the first adapter 20 to rise relative to the second adapter 100. Accordingly, the engagement balls 82 move (retract) radially inward along the retaining holes 52. The radially inward direction is the direction in which the engagement balls 82 move away from the clamp plate 120 and approach the second cam surface 80. As shown in FIG. 7 , the engagement balls 82 are positioned more inward than the inner circumferential surface of the through-holes 122 of the clamp plate 120. Therefore, the first adapter 20 disengages from the second adapter 100 without the engagement balls 82 interfering with the clamp plate 120. In other words, the second adapter 100 separates from the first adapter 20. Thereafter, in the same manner as described above, another second adapter 100 is coupled to the first adapter 20 of the distal arm AM. This completes the replacement of the end effector EC.

[0053] 7 shows an imaginary line extending from the first cam surface 78 and an imaginary line of the engaging ball 82 when the piston 64 and the cam member 66 have risen to the position shown in Fig. 6. As can be seen from these imaginary lines, if the cam member 66 does not have the second cam surface 80, the cam member 66 would need to be lifted significantly in order to retract the engaging ball 82 to the same position as when the cam member 66 has the second cam surface 80. In this case, the stroke amount of the cylinder portion 60 increases, and the end effector exchange device 12 would therefore become larger.

[0054] [Correction Based on Rule 91, 17.01.2025] In contrast, in this embodiment, the side surface of the cam member 66 has a second cam surface 80. The second angle β of the second cam surface 80 is greater than the first angle α of the first cam surface 78. Therefore, a sufficiently large retraction space is formed. This allows the engaging ball 82 to fully retract. That is, the engaging ball 82 can be disengaged from the adapter-side engaging surface 124 with a smaller stroke than when the second cam surface 80 is not present. This prevents the end effector exchange device 12 from becoming larger. As described above, when the first angle α is 15° to 45°, the second angle β is 45° to 75°, and the angle difference between the second angle β and the first angle α is 5° to 60°, the engaging ball 82 easily retracts.

[0055] It is assumed that an unexpected event will cause the supply of compressed air to the second pressure chamber 32 to stop. Alternatively, it is assumed that an unexpected event will cause the piston 64 to be unable to generate sufficient thrust. In such a case, the release bar 136 is operated. This operation will be described with reference to FIGS. 8 and 9.

[0056] As shown in Figure 8, the operator grasps the handle of the release bar 136 and inserts the tip of the release bar 136 into the separation operation hole 130, and then advances the release bar 136 toward the inside of the second adapter 100. This causes the tapered side surface at the tip of the release bar 136 to abut against the second cam surface 80, applying a pressing force to the second cam surface 80. The cam member 66 rises in response to this pressing force, changing from the locked position to the unlocked position. As shown in Figure 9, when the release bar 136 is advanced further, the cam member 66 rides up onto the release bar 136.

[0057] As described above, the second angle β is greater than the first angle α. Therefore, when the tip of the release bar 136 abuts against the second cam surface 80, the pressing force required to lift the cam member 66 is smaller than when the tip of the release bar 136 abuts against the first cam surface 78. As can be seen from this, by pressing against the second cam surface 80, the cam member 66 can be lifted with a small force.

[0058] Thereafter, for example, when the operator pulls the second adapter 100 in a direction away from the first adapter 20 (downward in the illustrated example), the engagement ball 82 moves (retreats) along the second cam surface 80. In other words, the first adapter 20 rises relative to the second adapter 100, and the first adapter 20 disengages from the second adapter 100.

[0059] Contrary to the illustrated example, the cylinder portion 60 can also be configured so that the locked state is established when the piston 64 is at top dead center. In this case, the unlocked state is established as the piston 64 descends. In this configuration, the first adapter 20 and the second adapter 100 can be separated when the piston 64 is at bottom dead center.

[0060] This embodiment has the following advantages.

[0061] As shown in FIG. 2, the side surface of the cam member 66 has a cam-side engagement surface 72 that contacts an engagement ball 82 in the locked position and a tapered surface 74 that contacts the engagement ball 82 in the unlocked position. The tapered surface 74 has a first cam surface 78 that is adjacent to the cam-side engagement surface 72 in the axial direction (the displacement direction of the piston 64) and a second cam surface 80 that is adjacent to the first cam surface 78 in the axial direction. As shown in FIG. 3, when the angle between the first cam surface 78 and the axial direction is a first angle α and the angle between the second cam surface 80 and the axial direction is a second angle β, the first angle α is smaller than the second angle β. In other words, α<β.

[0062] With this configuration, it is possible to increase the lifting force of the cylinder portion 60 while avoiding an increase in the stroke amount of the cylinder portion 60. In other words, it is possible to easily connect the first adapter 20 and the second adapter 100 while avoiding an increase in the size of the end effector exchange device 12.

[0063] In one embodiment, the angle difference between the second angle β and the first angle α is between 5° and 60°.

[0064] In one embodiment, the first angle α is between 15° and 45°, and the second angle β is between 45° and 75°.

[0065] In one aspect, the second adapter 100 has an adapter-side engagement surface 124 .

[0066] In either aspect, when the cam member 66 is in the unlocked position, the engagement ball 82 can easily retreat from the cam-side engagement surface 72 .

[0067] 2, when the cam member 66 is in the locked position, the engagement ball 82 is sandwiched between the cam-side engagement surface 72 and the adapter-side engagement surface 124. The cam member 66 has a stopper portion 76 that prevents the engagement ball 82 from displacing toward the piston 64.

[0068] Specifically, the engagement ball 82 is surrounded by the cam-side engagement surface 72, the adapter-side engagement surface 124, and the inner surface of the stopper portion 76. This prevents the engagement ball 82 from moving in the displacement direction of the piston 64. Therefore, the first adapter 20 and the second adapter 100 are difficult to separate.

[0069] The first adaptor 20 includes a first adaptor body 24 and a clamp base 40. The clamp base 40 has a retaining hole 52 that movably retains an engaging ball 82.

[0070] Since the engaging ball 82 is held in the holding hole 52 , the engaging ball 82 is unlikely to fall off the first adapter 20 .

[0071] As shown in Fig. 1, the second adapter 100 has a separation operation hole 130. As shown in Figs. 8 and 9, a release operation tool 134 (e.g., a release bar 136) is inserted into the separation operation hole 130. The release operation tool 134 inserted into the separation operation hole 130 abuts against the second cam surface 80.

[0072] Even if the supply of compressed air (working fluid) is stopped, the first adapter 20 can be manually separated from the second adapter 100 by using the release operating tool 134. Furthermore, when the release operating tool 134 abuts against the second cam surface 80, the force required to lift the cam member 66 is smaller than when the release operating tool 134 abuts against the first cam surface 78. In other words, the first adapter 20 and the second adapter 100 can be separated from each other with a small force.

[0073] The following additional notes are further disclosed regarding the above embodiment.

[0074] (Supplementary Note 1) The attachment / detachment device (10) of the present disclosure comprises a first adapter (20) and a second adapter (100) that is attachable to and detachable from the first adapter. The first adapter comprises a piston (64) that is driven by supplying and discharging a working fluid, a cam member (66) that is integrally connected to the piston, and an engagement ball (82) that abuts against a side surface of the cam member. When the cam member is in a locked position, the engagement ball protrudes, preventing separation of the first adapter and the second adapter. When the cam member is in an unlocked position, the engagement ball retracts, allowing separation of the first adapter and the second adapter.

[0075] The side surface of the cam member has a cam-side engagement surface (72) against which the engagement ball abuts in the locked position and a tapered surface (74) against which the engagement ball abuts in the unlocked position. The tapered surface has a first cam surface (78) adjacent to the cam-side engagement surface in the displacement direction of the piston, and a second cam surface (80) adjacent to the first cam surface in the displacement direction of the piston. In the above configuration, a first angle (α) which is an intersection angle between the first cam surface and the displacement direction of the piston is smaller than a second angle (β) which is an intersection angle between the second cam surface and the displacement direction of the piston.

[0076] This configuration increases the lifting force of the cylinder portion, which includes the piston, the cam member, and the engagement ball, while preventing the attachment / detachment device from becoming large. The lifting force is the force that pulls the second adapter toward the first adapter.

[0077] (Supplementary Note 2) In the attachment / detachment device described in Supplementary Note 1, an angle difference obtained by subtracting the first angle from the second angle may be 5° to 60°.

[0078] (Supplementary Note 3) In the attachment / detachment device described in Supplementary Note 1 or 2, the first angle may be 15° to 45°, and the second angle may be 45° to 70°.

[0079] (Supplementary Note 4) In the attachment / detachment device described in any one of Supplementary Notes 1 to 3, the second adapter has an adapter-side engagement surface (124) against which the engagement ball abuts in the locked position and from which the engagement ball moves away in the unlocked position.

[0080] In any of Supplementary Notes 2 to 4, when the cam member is in the unlocked position, the engagement ball can easily retreat from the cam-side engagement surface.

[0081] (Appendix 5) In the attachment / detachment device described in Appendix 4, the cam member may have a stopper portion (76) that prevents the engagement ball sandwiched between the cam side engagement surface and the adapter side engagement surface from displacing toward the piston in the locked position.

[0082] The engaging ball is surrounded by the cam-side engaging surface, the adapter-side engaging surface, and the inner surface of the stopper portion, preventing movement in the piston displacement direction, thereby making it difficult for the first adapter and the second adapter to separate.

[0083] (Appendix 6) In the attachment / detachment device described in any one of Appendices 1 to 5, the first adapter may include a first adapter body (24) and a clamp base (40), and the clamp base may have a retaining hole (52) that movably holds the engagement ball.

[0084] This configuration prevents the engaging ball from falling off the first adapter.

[0085] (Appendix 7) In the attachment / detachment device described in any one of Appendices 1 to 6, the second adapter has a separation operation hole (130) into which a release operation tool (134) is inserted, and the release operation tool inserted into the separation operation hole may abut against the second cam surface.

[0086] Even if the supply of hydraulic fluid is stopped, the first adapter can be manually separated from the second adapter by the release tool. Furthermore, because the release tool can abut against the second cam surface, the force applied to the cam member is smaller than when the release tool abuts against the first cam surface.

[0087] (Appendix 8) In the attachment / detachment device described in any one of Appendices 1 to 7, the attachment / detachment device may be an end effector exchange device (12), and the first adapter may be attached to a robot (RO), and an end effector (EC) may be attached to the second adapter.

[0088] Thus, a suitable example of the attachment / detachment device is an end effector exchange device.

[0089] The present invention is not limited to the above disclosure, and various configurations can be adopted without departing from the gist of the present invention.

Claims

1. A detachment device (10) comprising a first adapter (20) and a second adapter (100) detachable from the first adapter, wherein the first adapter comprises a piston (64) driven by the supply and discharge of hydraulic fluid, a cam member (66) integrally connected to the piston, and an engagement ball (82) abutting against a side surface of the cam member, wherein when the cam member is in a locked position, the engagement ball protrudes to prevent separation of the first adapter and the second adapter, and when the cam member is in an unlocked position, the engagement ball retracts to allow separation of the first adapter and the second adapter, and the side surface of the cam member has a cam-side engagement surface (72) against which the engagement ball abuts in the locked position and a tapered surface (74) against which the engagement ball abuts in the unlocked position, The tapered surface has a first cam surface (78) adjacent to the cam-side engagement surface in the displacement direction of the piston, and a second cam surface (80) adjacent to the first cam surface in the displacement direction of the piston, and a first angle (α) that is an intersection angle between the first cam surface and the displacement direction of the piston is smaller than a second angle (β) that is an intersection angle between the second cam surface and the displacement direction of the piston.

2. The attachment / detachment device according to claim 1, wherein the angle difference obtained by subtracting the first angle from the second angle is between 5° and 60°.

3. The attachment / detachment device according to claim 1, wherein the first angle is between 15° and 45°, and the second angle is between 45° and 70°.

4. A detaching device according to claim 1, wherein the second adapter has an adapter-side engagement surface (124) against which the engagement ball abuts in the locked position and from which the engagement ball is spaced in the unlocked position.

5. A detaching device according to claim 4, wherein the cam member has a stopper portion (76) that prevents the engagement ball sandwiched between the cam-side engagement surface and the adapter-side engagement surface from displacing toward the piston when in the locked position.

6. A detaching device according to claim 1, wherein the first adapter comprises a first adapter body (24) and a clamp base (40), and the clamp base has a retaining hole (52) in which the engaging ball is movably held.

7. A detachment device according to claim 1, wherein the second adapter has a separation operation hole (130) into which a release operation tool (134) is inserted, and the release operation tool inserted into the separation operation hole abuts against the second cam surface.

8. An attachment / detachment device according to any one of claims 1 to 7, wherein the attachment / detachment device is an end effector exchange device (12), the first adapter is attached to a robot (RO), and an end effector (EC) is attached to the second adapter.

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