Workpiece holding device

Abstract

The present invention provides a workpiece holding device that enables the clamping device to operate even without the use of a cylinder. The workpiece holding device (11) comprises: a main body (12); at least one shaft member (7) capable of contacting a workpiece (W); a clamping device (1) mounted on the main body (12) for insertion of the shaft member (7) and capable of switching between a non-clamping state for releasing the shaft member (7) and a clamping state for clamping the shaft member (7); and a trigger member (16) for switching the clamping device (1) between the non-clamping state and the clamping state. By directly contacting the workpiece (W) via or indirectly contacting at least a portion (7a) of the shaft member (7), the trigger member (16) moves relative to the main body (12), thereby switching the clamping device (1) from the non-clamping state (Fig. 3(a)) to the clamping state (Fig. 3(b)).

Description

TECHNICAL FIELD

[0001] The present application relates to a workpiece holding device that holds a workpiece, and particularly to a workpiece holding device that uses a clamping device. BACKGROUND

[0002] A clamping device that switches between a non-clamping state that releases a shaft member and a clamping state that clamps the shaft member is known (see Patent Document 1). The clamping device has an outer cylinder into which the shaft member is inserted, a rolling body that is disposed in a wedge-shaped space between the outer cylinder and the shaft, and a retainer that holds the rolling body. If the outer cylinder is relatively moved in one direction with respect to the retainer, the rolling body rolls into the small-diameter side of the wedge-shaped space, and the shaft member can be clamped. On the other hand, if the outer cylinder is relatively moved in the direction opposite to the one direction with respect to the retainer, the rolling body is moved to the large-diameter side of the wedge-shaped space, and the shaft member can be released.

[0003] If the clamping device is used, a workpiece holding device that grips, sucks, supports, or the like a workpiece can be constructed. For example, if a pair of shaft members are disposed on the left and right of the workpiece, and the workpiece is clamped by the pair of shaft members fixed by the clamping device, the workpiece can be gripped. In addition, if a suction pad is provided at the front end of the shaft member fixed by the clamping device, the workpiece can be sucked.

[0004] PRIOR ART DOCUMENTS

[0005] PATENT DOCUMENTS

[0006] Patent Document 1: Japanese Patent Application Publication No. H11-4508 SUMMARY

[0007] PROBLEMS TO BE SOLVED BY THE INVENTION

[0008] However, in the conventional clamping device, in order to switch the clamping device from the non-clamping state to the clamping state, an air cylinder is required. Therefore, there is a problem that the clamping device cannot be operated in an environment where compressed air cannot be used, or in an application where compressed air cannot be used.

[0009] Therefore, an object of the present application is to provide a workpiece holding device in which the clamping device can be operated even without using an air cylinder.

[0010] MEANS FOR SOLVING THE PROBLEMS

[0011] To solve the above problems, the present application is a workpiece holding device, comprising: a main body; at least one shaft member capable of contacting a workpiece; a clamping device mounted on the main body, into which the shaft member is inserted, and capable of being switched to a non-clamping state releasing the shaft member and a clamping state clamping the shaft member; and a trigger member for switching the clamping device to the non-clamping state and the clamping state, which is pressed by directly contacting the workpiece or indirectly contacting the workpiece via at least a part of the shaft member, so that the trigger member moves relatively to the main body, and the clamping device is switched from the non-clamping state to the clamping state.

[0012] Effects of the Invention

[0013] According to the present application, the clamping device can be switched from the non-clamping state to the clamping state even without using a cylinder. BRIEF DESCRIPTION OF DRAWINGS

[0014] Figure 1 is a sectional view of a clamping device assembled in the workpiece holding device of the present embodiment.

[0015] Figure 2 is a view showing another example of a clamping device.

[0016] Figure 3 is a plan view of the workpiece holding device of the first embodiment of the present application (before holding a workpiece). Figure 3 (a) of FIG. 1 shows a state before holding a workpiece, Figure 3 (b) of FIG. 1 shows a state after holding a workpiece).

[0017] Figure 4 is an enlarged view of the main body of the workpiece holding device of the first embodiment of the present application (before holding a workpiece). Figure 4 (a) of FIG. 2 shows a non-clamping state of a clamping device, Figure 4 (b) of FIG. 2 shows a clamping state).

[0018] Figure 5 is a perspective view of the workpiece holding device of the second embodiment of the present application (before holding a workpiece).

[0019] Figure 6 is a perspective view of the workpiece holding device of the second embodiment of the present application (after holding a workpiece).

[0020] Figure 7 is a horizontal sectional view of the main body of the workpiece holding device of the second embodiment of the present application (before holding a workpiece). Figure 7 (a) of FIG. 4 shows a non-clamping state of a clamping device, Figure 7 (b) of FIG. 4 shows a clamping state).

[0021] Figure 8is a horizontal sectional view of a shaft member of the workpiece holding device of the second embodiment of the present application Figure 8 (a) of FIG. 6 shows a non-clamping state of the clamping device, Figure 8 (b) of FIG. 6 shows a clamping state).

[0022] Figure 9 is a horizontal sectional view of a trigger member of the workpiece holding device of the second embodiment of the present application Figure 9 (a) of FIG. 7 shows an initial position of the trigger member, Figure 9 (b) of FIG. 7 shows a working position of the trigger member).

[0023] Figure 10 is an X-direction view of Figure 5

[0024] Figure 11 is a horizontal sectional view of a main body of the workpiece holding device of the third embodiment of the present application Figure 11 (a) of FIG. 8 shows a non-clamping state of the clamping device, Figure 11 (b) of FIG. 8 shows a clamping state).

[0025] Figure 12 is a diagram showing the workpiece holding device of the fourth embodiment of the present application Figure 12 (a) of FIG. 9 is a side view (non-clamping state), Figure 12 (b) of FIG. 9 is a bottom view).

[0026] Figure 13 is a side view (clamping state) of the workpiece holding device of the fourth embodiment of the present application.

[0027] Figure 14 is a diagram showing the workpiece holding device of the fifth embodiment of the present application Figure 14 (a) of FIG. 10 is a side view (non-clamping state), Figure 14 (b) of FIG. 10 is a bottom view).

[0028] Figure 15 is a side view (clamping state) of the workpiece holding device of the fifth embodiment of the present application.

[0029] Figure 16 is a diagram showing the workpiece holding device of the sixth embodiment of the present application Figure 16 (a) of FIG. 11 is a side view (non-clamping state), Figure 16 (b) of FIG. 11 is a bottom view).

[0030] Figure 17 is a side view (clamping state) of the workpiece holding device of the sixth embodiment of the present application. DETAILED DESCRIPTION

[0031] ​Hereinafter, a workpiece holding device according to embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be noted that the present invention can be embodied in various ways and is not limited to the embodiments described herein. These embodiments are provided so that those skilled in the art can understand the invention by making the specification sufficiently clear.

[0032] (Clamping device)

[0033] Figure 1 This is a cross-sectional view of the clamping device 1 assembled in the workpiece holding device of this embodiment. First, the structure of the clamping device 1 will be described. The clamping device 1 is configured to switch between a non-clamped state of the release shaft member 7 and a clamped state of the clamping shaft member 7. The clamping device 1 includes an outer cylinder 2, a rolling element 3, a retaining member 4, and a spring 5. The clamping device 1 is mounted on the main body 12 (see reference 12). Figure 3 Fixing plate 12a.

[0034] The outer cylinder 2 is cylindrical. A shaft member 7 is inserted into the outer cylinder 2. A directional bearing is formed on the inner surface of the outer cylinder 2. Figure 1 The tapered surface 2a gradually decreases in diameter along direction B. A wedge-shaped space S is formed between the outer surface of the shaft member 7 and the tapered surface 2a of the outer cylinder 2. The rolling element 3 is housed in this wedge-shaped space S. It should be noted that the orthogonal section of the outer cylinder 2 can be either circular or polygonal. The orthogonal section of the shaft member 7 can also be either circular or polygonal.

[0035] The rolling element 3 is a roller or a ball. The roller can be either bottle-shaped or drum-shaped. Multiple rolling elements 3 are arranged along the circumference of the wedge-shaped space S.

[0036] The retainer 4 holds the rolling element 3. The retainer 4 is cylindrical. An opening 4a is formed in the retainer 4 to receive the rolling element 3. The rolling element 3 is rotatably received in the opening 4a. One end of the retainer 4 protrudes axially from the outer cylinder 2. One end of the retainer 4 is fixed to the fixing plate 12a.

[0037] Spring 5 is housed in outer cylinder 2. Spring 5 is positioned between retaining ring 2b mounted on outer cylinder 2 and retainer 4. Spring 5 exerts force on rolling element 3 held in retainer 4 toward the small-diameter side of wedge-shaped space S.

[0038] like Figure 1As shown, when the outer cylinder is moved relative to the retainer 4 in direction A (one direction), the rolling element 3 rolls into the smaller diameter side of the wedge-shaped space S. The shaft member 7 is secured by the rolling element 3 and clamped by it (the clamping device 1 is in the clamped state). At this time, the load P acting on the shaft member 7 is transmitted to the fixed plate 12a via the rolling element 3 and the retainer 4. On the other hand, when the outer cylinder is moved relative to the retainer 4 in direction B (the opposite direction), the rolling element 3 moves towards the larger diameter side of the wedge-shaped space S. The shaft member 7 is released from the rolling element 3 and can move axially (the clamping device 1 is in the unclamped state).

[0039] like Figure 2 As shown, the outer cylinder 2 of the clamping device 1 can also be fixed to the fixing plate 12a. When the retaining member 4 moves relative to the outer cylinder 2 in the direction B, the rolling element 3 rolls into the smaller diameter side of the wedge-shaped space S, and the clamping device 1 is in a clamped state. The load P acting on the shaft member 7 is transmitted to the fixing plate 12a via the rolling element 3 and the outer cylinder 2. On the other hand, when the retaining member 4 moves relative to the outer cylinder 2 in the direction A, the rolling element 3 moves towards the larger diameter side of the wedge-shaped space S, and the clamping device 1 is in a non-clamped state.

[0040] (First Implementation)

[0041] Figure 3 The workpiece holding device 11 according to the first embodiment of the present invention is shown. Figure 3 (a) shows the state before the workpiece W is held. Figure 3 (b) shows the state after the workpiece W is held. It should be noted that in... Figure 3 The example shown is of using the workpiece holding device 11 as a vise to hold and fix the workpiece W, but the workpiece holding device 11 can also be assembled into a robot to transport the workpiece W.

[0042] 12 represents a pair of main bodies, 7 represents a shaft component, 1 represents a clamping device, and 14 represents a trigger mechanism. The main body 12, shaft component 7, clamping device 1, and trigger mechanism 14 are symmetrical. The structure of the left-side main body 12, shaft component 7, clamping device 1, and trigger mechanism 14 will be described below.

[0043] The main body 12 is equipped with multiple shaft members 7, multiple clamping devices 1, and a triggering mechanism 14. The number of shaft members 7 and clamping devices 1 is not particularly limited; for example, more than four shaft members 7 can be arranged in a matrix on the main body 12.

[0044] The main body 12 is movably supported on the base 17. The main body 12 moves forward and backward toward the workpiece W via a feeding mechanism. The feeding mechanism is not particularly limited; for example, a feed screw, cylinder, etc., can be used. Figure 3The feed screw is shown in (a) and (b). A right-hand thread and a left-hand thread are formed on the screw shaft 18. A ball screw nut (not shown) is provided on the body 12, which engages with the right-hand and left-hand threads of the screw shaft. If the screw shaft 18 is rotated using a handle 20, a motor, etc., the body 12 moves forward and backward toward the workpiece W through the action of the ball screw.

[0045] The main body 12 includes a fixed plate 12a and a movable plate 12b. A retainer 4 of the clamping device 1 (see reference) is mounted on the fixed plate 12a. Figure 3 of (b) Figure 4 (a) and (b)). The outer cylinder 2 of the clamping device 1 is installed on the movable plate 12b. The movable plate 12b is clamped by the spring 5 of the clamping device 1 (see reference). Figure 1 A force is applied to the rod 15 of the triggering mechanism 14. It should be noted that the outer cylinder 2 can also be installed on the fixed plate 12a, and the retaining member 4 can be installed on the movable plate 12b. Alternatively, a spring (not shown) can be provided between the fixed plate 12a and the movable plate 12b to apply force from the movable plate 12b to the rod 15.

[0046] The shaft member 7 is axially movable and supported on the main body 12. A direct-acting bearing (not shown), such as a ball bearing sleeve, is provided on the fixed plate 12a to guide the axial movement of the shaft member 7. A contact 7a is provided at the front end of the shaft member 7 to contact the workpiece W. The contact 7a is not particularly limited and can be, for example, a pointed rubber in the shape of a bullet or a cone, or an adsorption pad. A spring 19 (see reference) is provided between the contact 7a and the main body 12 to allow the shaft member 7 to protrude from the main body 12. Figure 4 (a)).

[0047] like Figure 3 As shown in (a), the triggering mechanism 14 includes a shaft-shaped triggering member 16 and a rod 15. The triggering member 16 and the rod 15 are configured to switch the clamping device 1 to a non-clamping state and a clamping state. The triggering member 16 is axially movable and supported on the main body 12. A direct-acting bearing (not shown), such as a ball bearing sleeve, is provided on the fixed plate 12a to guide the axial movement of the triggering member 16. The front end 16a of the triggering member 16 is flange-shaped and can contact the workpiece W. The position of the front end 16a of the triggering member 16 is determined according to the concavity or convexity of the workpiece W. The rear end 16b of the triggering member 16 is flange-shaped and can contact the reset member 23. The reset member 23 is mounted on the base 17.

[0048] The lever 15 is tilted about the pivot 16c. The lever 15 changes the distance between the fixed plate 12a and the movable plate 12b as the trigger member 16 moves relative to the main body 12. Each lever 15 is, for example, L-shaped and has a short side 15a and a long side 15b (see reference). Figure 4(a)). The end of the long side 15b is connected to the trigger member 16 in a tilting motion. The short side 15a is disposed between the fixed plate 12a1 and the movable plate 12b. A bearing 27 is provided on the short side 15a that contacts the movable plate 12b and the fixed plate 12a1 (see reference). Figure 4 (a)). It should be noted that the structure of rod 15 is not limited to the above.

[0049] like Figure 3 As shown in (a), when the main body 12 moves to the initial position and the rear end 16b of the triggering member 16 contacts the reset member 23, the clamping device 1 switches from the clamping state to the non-clamping state. Figure 3 As shown in (b), when the body 12 moves toward the workpiece W, the clamping device 1 is in a non-clamping state, so the shaft member 7 mimics the shape of the workpiece W. Preferably, the position of the shaft member 7 of each clamping device 1 is adjusted so that it contacts the workpiece W before the trigger member 16.

[0050] like Figure 3 As shown in (b), when the main body 12 moves further toward the workpiece W and the front end 16a of the trigger member 16 comes into direct contact with the workpiece W, the trigger member 16 moves relative to the main body 12, and the clamping device 1 switches from a non-clamping state to a clamping state. Therefore, the shaft member 7 is fixed, and the workpiece W can be held using the shaft member 7. When holding the workpiece W, the shaft member 7 mimics the shape of W, thus enabling the holding of a variety of workpieces W.

[0051] Figure 4 (a) and (b) show enlarged views of the main body 12, shaft member 7, and triggering mechanism 14. Figure 4 (a) shows the non-clamped state. Figure 4 (b) shows the clamped state. When as Figure 3 When the rear end 16b of the trigger member 16 contacts the reset member 23 as shown in (a), Figure 4 As shown in (a), the trigger member 16 moves relative to the body 12. Figure 4 The relative movement δ to the right of (a) is thus achieved. Therefore, the short side 15a of the rod 15 rotates in a manner that it stands upright between the fixed plate 12a1 and the movable plate 12b, and the outer cylinder 2 moves relative to the retainer 4. Figure 4 The left side of (a) moves relative to the left. As a result, the clamping device 1 switches from the clamping state to the non-clamping state.

[0052] On the other hand, when Figure 3 When the front end 16a of the trigger member 16 contacts the workpiece W as shown in (b), Figure 4 As shown in (b), the trigger member 16 moves relative to the body 12. Figure 4The leftward relative movement δ of (b) is thus caused by the short side 15a of the rod 15 rotating at an angle between the fixed plate 12a1 and the movable plate 12b, and the outer cylinder 2 moving relative to the retainer 4 towards the leftward relative movement δ. Figure 4 The right side of (b) moves relative to the clamping device. As a result, the clamping device 1 switches from the non-clamping state to the clamping state.

[0053] The structure and function of the workpiece holding device 11 of this embodiment have been explained above. The workpiece holding device 11 of this embodiment achieves the following effects.

[0054] By directly contacting the workpiece W with the trigger component 16, the trigger component 16 moves relative to the main body 12, and the clamping device 1 switches from the non-clamping state to the clamping state. Therefore, even without using a cylinder, the clamping device 1 can be switched from the non-clamping state to the clamping state.

[0055] By contacting the trigger member 16 with the reset member 23, the trigger member 16 moves relative to the main body 12, and the clamping device 1 switches from the clamping state to the non-clamping state. Therefore, the clamping device 1 can be switched from the clamping state to the non-clamping state even without using a cylinder.

[0056] A pair of main bodies 12 are configured to clamp the workpiece W, thus enabling the holding of a wide variety of workpieces W.

[0057] (Second Implementation)

[0058] Figure 5 as well as Figure 6 A perspective view of the workpiece holding device 41 according to the second embodiment of the present invention is shown. Figure 5 The initial position of the main body 42 is shown (the state where the workpiece W is not being held). Figure 6 The state in which the workpiece W is held is shown. The workpiece holding device 41 of the second embodiment is mounted on the front axis of a robot (not shown) and serves as the robot's hand.

[0059] 43 is the base, 42 is a pair of main bodies (left and right), 7 is the shaft member, and 51 is the trigger member. In the first embodiment, the clamping device 1 switches from a non-clamping state to a clamping state by directly contacting the workpiece W through the trigger member 16. In contrast, in the second embodiment, as... Figure 6 As shown, the clamping device 1 switches from a non-clamping state to a clamping state by indirectly contacting the workpiece W via the contact 7a of the shaft member 7 through the trigger member 51.

[0060] like Figure 5As shown, a pair of main bodies 42 are supported on a base 43, capable of moving forward and backward relative to the workpiece W. The movement of the main bodies 42 is guided by a linear guide. The linear guide includes a guide rail 45 fixed to the base 43 and a block 46 fixed to the main body 42. A ball screw nut 47 is assembled on the block 46. A screw shaft 48 with right-hand and left-hand threads is screwed into the ball screw nut 47. The rotation of the motor 44 is transmitted to the screw shaft 48 via a transmission mechanism 49 such as a belt and pulleys. When the screw shaft 48 rotates, the pair of main bodies 42 move forward and backward relative to the workpiece W.

[0061] Figure 7 The internal structure of the main body 42 is shown. Figure 7 (a) shows the non-clamped state of clamping device 1. Figure 7 (b) shows the clamping state of clamping device 1. Figure 7 As shown, the main body 42 is assembled with a shaft member 7 and a trigger member 51.

[0062] Figure 8 The main body 42 and shaft member 7 are shown. The main body 42 includes fixed plates 42a and 42b and a movable plate 42c. The retainer 4 of the clamping device 1 is mounted on the fixed plate 42b (see reference). Figure 1 , Figure 8 (b)). The outer cylinder 2 of the clamping device 1 is mounted on the movable plate 42c. However, the movable plate 42c is not fixed to the outer cylinder 2, but only contacts the flange 2c of the outer cylinder 2. This is to ensure the concentricity of the outer cylinder 2 and the shaft member 7. The outer cylinder 2 is clamped by the spring 5 of the clamping device 1 (see reference). Figure 1 A force is applied to the movable plate 42c. The movable plate 42c is clamped by the spring 5 of the clamping device 1, which then applies force to the rod 54 of the triggering mechanism 14 (see reference). Figure 7 (a) Applying force.

[0063] like Figure 9 As shown in (a), a direct-acting bearing 52, such as a bushing, is mounted on the movable plate 42c. Shafts 53, into which the direct-acting bearings 52 are inserted, are fixed to the fixed plates 42a and 42b. The movement of the movable plate 42c is guided by the direct-acting bearings 52 and the shafts 53.

[0064] like Figure 8As shown in (a), the shaft member 7 is axially movable and supported on the main body 42. Direct-acting bearings (not shown), such as ball bearing sleeves, are installed on the fixed plates 42a and 42b to guide the axial movement of the shaft member 7. The retaining member 4 of the clamping device 1 is mounted on the fixed plate 42b via these direct-acting bearings. A contact 7a is provided at the front end of the shaft member 7, capable of contacting the workpiece W. The contact 7a is not particularly limited; for example, it can be a pointed rubber or suction pad in the shape of a bullet or cone. A spring 19 is provided between the contact 7a and the fixed plate 42a to allow the shaft member 7 to protrude from the main body 42. The protruding state of the shaft member 7 is maintained by the contact of the limiting member 7c at the rear end of the shaft member 7 with the fixed plate 42b.

[0065] like Figure 9 As shown in (a), the triggering member 51 includes a plate portion 51a and a shaft portion 51b fixed to the plate portion 51a. The plate portion 51a covers the workpiece W side of the main body 42 (see reference). Figure 5 A through hole 51a1 for the shaft member 7 to pass through is formed in the plate portion 51a (see reference). Figure 5 The diameter of the through hole 51a1 is larger than the diameter of the spring 19 wound around the shaft member 7, but smaller than the diameter of the contact 7a. When the contact 7a contacts the workpiece W and the shaft member 7 retracts, the rear end of the contact 7a contacts the plate portion 51a (see reference). Figure 7 (b)). The rear end portion 51b1 of the shaft portion 51b protrudes from the main body 42. The rear end portion 51b1 of the shaft portion 51b can engage with the angled reset member 43a fixed to the base 43 (see reference). Figure 5 )touch.

[0066] like Figure 9 As shown in (a), the triggering member 51 is supported on the main body 42 so as to be axially movable. A direct-acting bearing 55, such as a bushing, is fixed to the plate portion 51a of the triggering member 51. A shaft 56 into which the direct-acting bearing 55 is inserted is fixed to the fixed plate 42a. In addition, a direct-acting bearing (not shown), such as a bushing, is mounted on the fixed plate 42a to guide the movement of the shaft portion 51b of the triggering member 51.

[0067] The lever 54 is connected to the shaft 51b in a tilting motion around the pivot 51b2. The lever 54 is, for example, triangular in shape. Bearings 54a and 54b are provided at the two corners of the lever 54 other than the pivot 51b2. The distance between the fixed plate 42a and the movable plate 42c changes as the trigger member 51 moves relative to the main body 42.

[0068] Figure 10 yes Figure 5 The X-axis view shows the axial view of the main body 42. (See attached image.) Figure 5 As shown, multiple shaft members 7 are arranged parallel to each other on the main body 42. Figure 10As shown, viewed axially from the main body 42, the plurality of shaft members 7 include: a first shaft member 7-1, which is disposed at the vertex of the first regular hexagon h1; and a second shaft member 7-2, which is disposed at the vertex of a second regular hexagon h2, one side of which is longer than the first regular hexagon h1 and substantially offset by 30° relative to the first regular hexagon h1. A triangle, preferably an equilateral triangle, is formed by the two inner first shaft members 7-1 and the outer second shaft member 7-2. The shaft portion 51b and the rod 54 of the trigger member 51 are disposed inside the first regular hexagon h1 (see reference). Figure 9 Four shafts 56, for example, are arranged on the outside of the second regular hexagon h2 to guide the trigger member 51 (see reference). Figure 9 (a) and, for example, four shafts 53 for guiding the movable plate 42c (see reference). Figure 9 (a)). When viewed axially from the main body 42, shafts 53 and 56 are arranged at equal distances from the two adjacent second shaft members 7-2.

[0069] It should be noted that the first shaft member 7-1 and the second shaft member 7-2 can also be positioned at the vertices of a regular n-gon (n≥4), and the second regular n-gon h2 can be offset by 180° / n relative to the first regular n-gon h1. Furthermore, one or more shaft members 7 can be positioned inside the first regular n-gon h1, or one or more shaft members 7 can be positioned outside the second regular n-gon h2. Additionally, the number of shafts 56 guiding the trigger member 51 can be set to 3 or less, and the number of shafts 53 guiding the movable plate 42c can be set to 3 or less.

[0070] The function of the holding device 41 in the second embodiment will be explained. For example... Figure 5 As shown, when the main body 42 is moved to the initial position by the motor 44, the rear end 51b1 of the shaft portion 51b of the trigger member 51 contacts the reset member 43a, the trigger member 51 moves to the initial position, and the clamping device 1 switches from the clamping state to the non-clamping state.

[0071] That is, when Figure 7 When the rear end 51b1 of the shaft portion 51b of the triggering member 51, as shown in (a), contacts the reset member 43a, the triggering member 51 moves relative to the right by δ relative to the main body 42. As a result, the rod 54 tilts, the gap between the fixed plate 42a and the movable plate 42c widens, the outer cylinder 2 of the clamping device 1 moves relative to the retainer 4 to the left, and the clamping device 1 switches from the clamping state to the non-clamping state.

[0072] Next, when the main body 42 is moved toward the workpiece W by the motor 44, as... Figure 6As shown, the contact 7a of the shaft member 7 contacts the workpiece W, thus the shaft member 7 conforms to the shape of the workpiece W. When the main body 42 moves further toward the workpiece W and the contact 7a of the shaft member 7 contacts the trigger member 51, the trigger member 51 contacts the workpiece W via the contact 7a, and the trigger member 51 moves relative to the main body 42. Thus, the clamping device 1 switches from a non-clamping state to a clamping state.

[0073] That is, such as Figure 7 As shown in (b), when the triggering member 51 moves δ to the left relative to the main body 42, the rod 54 tilts, and the movable plate 42c approaches the fixed plate 42a. Consequently, the outer cylinder 2 of the clamping device 1 moves relative to the retaining member 4... Figure 7 The rightward relative movement of (b) is achieved, and the clamping device 1 switches from the non-clamping state to the clamping state. The unidirectional (leftward) movement of the shaft member 7 is restricted by the clamping device 1, thus the workpiece W can be held by the shaft member 7.

[0074] like Figure 6 As shown, when the triggering member 51 operates and the clamping device 1 switches from the non-clamping state to the clamping state, the load applied to the motor 44 increases, and the current flowing through the motor 44 increases. If the current flowing through the motor 44 increases, the motor control device 61 (see reference...) Figure 5 This will stop motor 44.

[0075] like Figure 5 As shown, the current flowing through the motor 44 is detected by the current sensor 62. The motor control device 61 includes a host controller 61a that gives commands to the motor 44 and a driver 61b that supplies power to the motor 44. The host controller 61a is a computer that includes a storage device storing a program for controlling the motor 44, RAM storing current values, a processor for executing the program, etc. When the current value detected by the current sensor 62 is above a threshold value, the host controller 61a stops the motor 44.

[0076] The structure and function of the workpiece holding device 41 according to the second embodiment have been explained above. The workpiece holding device 41 according to the second embodiment achieves the following effects.

[0077] The trigger member 51 indirectly contacts the workpiece W via the contact 7a of the shaft member 7, thereby causing the trigger member 51 to move relative to the main body 42, and the clamping device 1 switches from a non-clamping state to a clamping state. Therefore, the clamping device 1 can be switched from a non-clamping state to a clamping state even without using a cylinder. In addition, the indirect contact between the trigger member 51 and the workpiece W via the contact 7a prevents damage to the workpiece W.

[0078] The trigger member 51 has a plate portion 51a, so that the plate portion 51a can be pressed by the contact 7a, which contacts the workpiece W and retracts the most, regardless of where the protrusion of the workpiece W is located. Therefore, the trigger member 51 can be operated regardless of the shape of the workpiece W.

[0079] When viewed from the axial direction of the main body 42, the multiple shaft members 7 have a first shaft member 7-1 arranged at the vertex of the first regular n-gon h1 and a second shaft member 7-2 arranged at the vertex of the second regular n-gon h2. Therefore, a triangle can be formed by two adjacent inner first shaft members 7-1 and one outer second shaft member 7-2, and the multiple shaft members 7 can be arranged in a dense state.

[0080] When viewed from the axial direction of the main body 42, the shaft portion 51b and the rod 54 are arranged inside the first regular n-gon h1, thus making efficient use of space and enabling the main body 42 to be miniaturized.

[0081] When viewed from the axial direction of the main body 42, the shaft 56 that guides the triggering member 51 and the shaft 53 that guides the movable plate 42c are arranged on the outside of the second regular n-gon h2, thus making efficient use of space and enabling the main body 42 to be miniaturized.

[0082] A pair of main bodies 42 are configured to clamp the workpiece W. A motor 44 drives the pair of main bodies 42. The motor 44 stops when its current exceeds a threshold value. Therefore, the same program can be used to control the motor 44 for both thin and thick workpieces W. If the threshold value is adjusted according to the hardness of the workpiece W, both hard and soft workpieces can be held.

[0083] (Third Implementation)

[0084] Figure 11 The workpiece holding device 71 according to the third embodiment of the present invention is shown. Figure 11 (a) and Figure 7 Similarly, (a) shows the non-clamped state of clamping device 1. Figure 11 (b) and Figure 7 (b) similarly shows the clamping state of clamping device 1. The structure of the main body, shaft member, clamping device, trigger member, and rod is the same as in the second embodiment, therefore the same reference numerals are used, and their descriptions are omitted.

[0085] In the second embodiment, the trigger member 51 is reset to its initial position (see reference 43a) by contacting the shaft portion 51b of the trigger member 51 with the reset member 43a. Figure 5 , Figure 7 (a)). In contrast, in the third embodiment, as Figure 11 As shown in (a), the trigger member 51 is reset to the initial position by means of the spring 72.

[0086] Spring 72 is clamped between the fixing plate 42a of the main body 42 and the direct-acting bearing 55. For example... Figure 11 As shown in (b), in the clamping state of the clamping device 1, when the main body 42 is moved away from the workpiece W, the contact 7a of the shaft member 7 moves away from the plate portion 51a under the action of the spring 19. Figure 11 As shown in (a), when the contact 7a leaves the plate 51a, the trigger member 51 moves to the right under the action of the spring 72, returning to its initial position. As a result, the rod 54 tilts, thereby switching the clamping device 1 from the clamping state to the non-clamping state.

[0087] According to the workpiece holding device 71 of the third embodiment, the trigger member 51 is reset to the initial position by means of the spring 72. Therefore, it is not necessary to provide an angled (protruding) reset member 43a on the base 43, which can increase the stroke of the main body 42. Alternatively, the stroke can be easily changed by changing the installation position of the workpiece holding device 71.

[0088] (Fourth Implementation)

[0089] Figure 12 (a) and (b) show the workpiece holding device 21 according to the fourth embodiment of the present invention. Figure 12 (a) is a side view. Figure 12 (b) is a bottom view. The workpiece holding device 21 of the fourth embodiment is also mounted on the front axis of the robot and serves as the robot's hand. Multiple shaft members 7, multiple clamping devices 1, and a triggering mechanism 14 are arranged in the main body 22. At the lower end of each shaft member 7 facing the vertical direction, an adsorption pad 7b is provided as an adsorption member for adsorbing the workpiece W. The shaft member 7 is hollow and connected to the vacuum generator 26 via a flexible hose. Figure 12 As shown in (b), the shaft member 7 and the adsorption pad 7b are arranged in a matrix (vertical and horizontal) on the main body 22. The shaft member 7 is forced into a protruding state by the spring 25.

[0090] In the first embodiment, the trigger member 16 contacts the reset member 23, thereby causing the trigger member 16 to move relative to the main body 12, and the clamping device 1 switches from a clamping state to a non-clamping state (see reference). Figure 3 (a)). In contrast, in the fourth embodiment, the trigger member 16 is moved relative to the main body 22 by the spring 24 that applies force to the trigger member 16 in the protruding state, and the clamping device 1 switches from the clamping state to the non-clamping state.

[0091] 22 is the main body, 22a is the fixed plate, and 22b is the movable plate. A ball bearing sleeve (not shown) is installed on the fixed plate 22a to guide the movement of the shaft member 7. The retainer 4 of the clamping device 1 is fixed on the fixed plate 22a via the ball bearing sleeve (not shown). The outer cylinder 2 of the clamping device 1 is installed on the movable plate 22b. The structure of the clamping device 1 is the same as that of the clamping device 1 in the first embodiment.

[0092] 16 is a trigger member, and 15 is a rod. The front end 16a of the trigger member 16 is flanged and can contact the workpiece W. The rod 15 is disposed between the fixed plate 22a and the movable plate 22b. A spring 24 is provided between the front end 16a of the trigger member 16 and the fixed plate 22a to apply force to the trigger member 16 in a protruding state. It should be noted that, as in the second embodiment, the front end 16a of the trigger member 16 can also be made into a plate shape of approximately the same size as the main body 22, with a through hole formed in the front end 16a of the plate shape for the shaft member 7 to pass through, and the adsorption pad 7b in contact with the front end 16a.

[0093] Figure 12 (a) shows the non-clamped state of clamping device 1. Figure 13 Indicates the clamped state. For example... Figure 12 As shown in (a), in the unclamped state of the clamping device 1, when the main body 22 descends toward the workpiece W, as Figure 13 As shown, the suction pad 7b of the shaft member 7 contacts the workpiece W, and the shaft member 7 overcomes the spring force of the spring 25 and conforms to the shape of the workpiece W.

[0094] As the main body 22 descends further toward the workpiece W, the front end 16a of the trigger member 16 contacts the workpiece W, and the trigger member 16 rises against the spring force of the spring 24. At this time, as... Figure 13 As shown, the short side 15a of the rod 15 rotates at an angle between the fixed plate 22a and the movable plate 22b, the outer cylinder 2 rises relative to the retainer 4, and the clamping device 1 switches from a non-clamping state to a clamping state. If the adsorption pad 7b is made into a vacuum while the shaft member 7 is fixed by the clamping device 1, the workpiece W can be gripped.

[0095] On the other hand, if the vacuum of the adsorption pad 7b is released and the main body 22 is separated from the workpiece W, the triggering component 16 will be reset by the force of the spring 24. Figure 12 The initial position is shown in (a). At this time, the short side 15a of the rod 15 rotates in such a way that it stands between the fixed plate 22a and the movable plate 22b, the outer cylinder 2 descends relative to the retainer 4, and the clamping device 1 switches from the clamping state to the non-clamping state.

[0096] According to the fourth embodiment, the following effects are achieved.

[0097] By triggering the component 16 to contact the workpiece W, the component 16 moves relative to the main body 22, and the clamping device 1 switches from the non-clamping state to the clamping state. Therefore, the clamping device 1 can be switched from the non-clamping state to the clamping state even without using a cylinder.

[0098] The spring 24 resets the trigger member 16 to its initial position, so the clamping device 1 can be switched from the clamping state to the non-clamping state even without the use of a cylinder.

[0099] The shaft member 7 is formed as a hollow structure, and an adsorption pad 7b is provided at the front end of the shaft member 7, so that the workpiece W can be adsorbed.

[0100] (Fifth Implementation)

[0101] Figure 14 (a) and (b) show the workpiece holding device 31 according to the fifth embodiment of the present invention. Figure 14 (a) is a side view. Figure 14 (b) is a bottom view. In the fifth embodiment, similar to the fourth embodiment, a plurality of shaft members 7, a plurality of clamping devices 1, and a triggering mechanism 14 are arranged in the main body 32. An adsorption pad 7b, serving as an adsorption member for adsorbing the workpiece W, is provided at the front end of each shaft member 7. The shaft member 7 is hollow and connected to the vacuum generator 26. The structures of the shaft member 7, the triggering mechanism 14, and the vacuum generator 26 are the same as in the fourth embodiment, therefore the same reference numerals are used and their descriptions are omitted.

[0102] In the fourth embodiment, a clamping device 1 is provided on each shaft member 7 to restrict the movement of the shaft member 7 in one direction (unidirectional). In contrast, in the fifth embodiment, two clamping devices 1 are provided on each shaft member 7 to restrict the movement of the shaft member 7 in two directions (bidirectional).

[0103] The main body 32 includes two movable plates 32b and two fixed plates 32a. The retainer 4 of the clamping device 1 is fixed to each fixed plate 32a via ball bearing sleeves (not shown). The outer cylinder 2 of the clamping device 1 is mounted on each movable plate 32b. The two clamping devices 1 disposed on each shaft member 7 are arranged such that their large-diameter portions in a wedge-shaped space face each other. The structure of the clamping device 1 itself is the same as that of the clamping device 1 in the first embodiment; therefore, the same reference numerals are used, and its description is omitted.

[0104] The lever 15 of the triggering mechanism 14 is positioned between the two movable plates 32b. Figure 14 (a) shows the non-clamped state. Figure 15 Indicates the clamped state. For example... Figure 14 As shown in (a), in the unclamped state, when the body 32 descends toward the workpiece W, as Figure 15As shown, the suction pad 7b of the shaft member 7 contacts the workpiece W, and the shaft member 7 overcomes the spring force of the spring 25 and conforms to the shape of the workpiece W.

[0105] As the main body 32 descends further toward the workpiece W, the front end 16a of the trigger member 16 contacts the workpiece W, and the trigger member 16 rises relative to the main body 32, overcoming the spring force of the spring 24. At this time, as... Figure 15 As shown, the short side 15a of the rod 15 rotates at an angle between the two movable plates 32b, bringing the two outer cylinders 2 closer together, and the clamping device 1 switches from a non-clamping state to a clamping state. If the adsorption pad 7b is made into a vacuum while the shaft member 7 is fixed by the clamping device 1, the workpiece W can be gripped.

[0106] On the other hand, if the vacuum of the adsorption pad 7b is released and the main body 32 is separated from the workpiece W, the triggering component 16 is reset by the force of the spring 24. Figure 14 The reset position is shown in (a). At this time, as Figure 14 As shown in (a), the short side 15a of the rod 15 rotates in a manner that it stands between the two movable plates 32b, the two outer cylinders 2 separate, and the clamping device 1 switches from the clamping state to the non-clamping state.

[0107] According to the fifth embodiment, in addition to having the same effect as the fourth embodiment, it also has the following effect: two clamping devices 1 are provided for each shaft member 7 to restrict the movement of the shaft member 7 in both directions (bidirectional), so that the workpiece W can be stably held.

[0108] (Sixth Implementation Method)

[0109] Figure 16 (a) and (b) show the workpiece holding device 81 according to the sixth embodiment of the present invention. Figure 16 (a) is a side view. Figure 16 (b) is a bottom view. In the sixth embodiment, multiple shaft members 7 and multiple clamping devices 1 are also arranged on the main body 32. An adsorption pad 7b for adsorbing the workpiece W is provided at the front end of each shaft member 7. The shaft member 7 is hollow and connected to a vacuum generator (not shown). Two clamping devices 1 are provided on each shaft member 7 to restrict the movement of each shaft member 7 in two directions (bidirectional). The structure of the main body 32, shaft members 7, and clamping devices 1 is the same as in the fifth embodiment, therefore the same reference numerals are used and their descriptions are omitted.

[0110] The spacing between the two movable plates 32b is adjusted using a working cylinder device 85, such as a cylinder. The main body 85a of the working cylinder device 85 is mounted on the upper movable plate 32b. The rod 85b of the working cylinder device 85 is mounted on the lower movable plate 32b. Figure 16As shown in (a), when the distance between the two movable plates 32b is widened using the working cylinder device 85, the clamping device 1 becomes unclamped. Figure 17 As shown, when the working cylinder device 85 reduces the distance between the two movable plates 32b, the clamping device 1 is in a clamping state.

[0111] like Figure 16 As shown in (b), when viewed axially from the main body 32, the plurality of shaft members 7 include: a first shaft member 7-1, which is disposed at the vertex of the first regular hexagon h1; and a second shaft member 7-2, which is disposed at the vertex of a second regular hexagon h2, one side of which is longer than the first regular hexagon h1 and substantially offset by 30° relative to the first regular hexagon h1. A working cylinder device 85 (see reference) is disposed inside the first regular hexagon h1. Figure 16 (a) Four shafts 84, for example, are arranged on the outside of the second regular hexagon h2 to guide the movable plate 32b. The shafts 84 are arranged at equal distances from the two adjacent second shaft members 7-2. A direct-acting bearing 83, such as a bushing, for inserting the shafts 84 is installed on the movable plate 32b.

[0112] It should be noted that the first axis member 7-1 and the second axis member 7-2 can also be positioned at the vertices of a regular n-gon (n≥4), and the second regular n-gon h2 can be offset by 180° / n relative to the first regular n-gon h1.

[0113] The function of the workpiece holding device 81 in the sixth embodiment will be explained. Figure 16 In the unclamped state shown in (a), when the body 32 is brought close to a workpiece not shown, as Figure 17 As shown, the adsorption pad 7b of the shaft member 7 contacts the workpiece and mimics the shape of the workpiece. If the working cylinder device 85 is activated to switch the clamping device 1 from the non-clamping state to the clamping state, and the adsorption pad 7b is made into a vacuum, the workpiece can be adsorbed.

[0114] The workpiece holding device 81 according to the sixth embodiment has the following effects.

[0115] When viewed from the axial direction of the main body 32, the multiple shaft members 7 have a first shaft member 7-1 arranged at the vertex of the first regular n-gon h1 and a second shaft member 7-2 arranged at the vertex of the second regular n-gon h2. Therefore, a triangle can be formed by two adjacent inner first shaft members 7-1 and one outer second shaft member 7-2, and the multiple shaft members 7 can be arranged in a dense state.

[0116] When viewed from the axial direction of the main body 32, the working cylinder device 85 is arranged inside the first regular n-gon h1, thus making effective use of space and enabling the main body 32 to be miniaturized.

[0117] When viewed from the axial direction of the main body 32, a shaft 84 for guiding the movable plate 32b is arranged on the outside of the second regular n-gon h2, thus making efficient use of space and enabling the main body 32 to be miniaturized.

[0118] This specification is based on Japanese Special Application No. 2020-089319 filed on May 22, 2020, and Japanese Special Application No. 2020-150244 filed on September 8, 2020. All of their contents are contained herein.

[0119] Explanation of reference numerals in the attached figures

[0120] 1…clamping device, 7…shaft member, 7a…contact (part of shaft member), 7b…adsorption pad (adsorption member), 7-1…first shaft member, 7-2…second shaft member, 11, 21, 31, 41, 71, 81…workpiece holding device, 12, 22, 32, 42…main body, 15, 54…rod, 16, 51…trigger member, 23, 43a…reset member, 24, 72…spring, 32b, 42c…movable plate, 44…motor, 51a…plate part, 51b…shaft part (part of trigger member), 53, 84…shaft guiding the movable plate, 56…shaft guiding the trigger member, 61…motor control device, 85…working cylinder device, W…workpiece, h1…first regular hexagon, h2…second regular hexagon.

Claims

1. A workpiece holding device, comprising: a main body; at least one shaft member capable of contacting a workpiece; a clamping device installed to the main body, into which the shaft member is inserted, and capable of switching to a non-clamping state in which the shaft member is released and a clamping state in which the shaft member is clamped; and a trigger member for switching the clamping device to the non-clamping state and the clamping state, a pair of the main bodies being arranged so as to sandwich the workpiece, the main body including a fixed plate and a movable plate, the trigger member being pressed by being directly contacted with the workpiece or indirectly contacted with the workpiece via at least a part of the shaft member, so that the trigger member is relatively moved with respect to the main body, the movable plate is relatively moved with respect to the fixed plate, and the clamping device is switched from the non-clamping state to the clamping state.

2. The workpiece holding device according to claim 1, wherein the trigger member has a plate portion through which the at least one shaft member passes and with which a tip of the shaft member can be contacted.

3. The workpiece holding device according to claim 1, wherein a lever for switching the clamping device to the non-clamping state and the clamping state is linked to the trigger member so as to be able to tilt.

4. The workpiece holding device according to any one of claims 1 to 3, wherein the trigger member is relatively moved with respect to the main body by being contacted with a return member or by a spring, so that the clamping device is switched from the clamping state to the non-clamping state.

5. The workpiece holding device according to any one of claims 1 to 3, wherein a pair of the main bodies are arranged so as to sandwich the workpiece, the workpiece holding device including a motor that advances and retreats the main body with respect to the workpiece, and a motor control device that stops the motor when a current value of the motor becomes a threshold value or more.

6. The workpiece holding device according to any one of claims 1 to 3, wherein the shaft member is formed to be hollow, and has a suction member that suctions the workpiece at a tip end. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

Images