Workpiece transport hand

Abstract

To provide a workpiece transfer hand capable of sucking and holding a workpiece without a pump for vacuum adsorption or piping inside a robot.SOLUTION: A workpiece transfer hand A1 according to the present invention includes a support 1 that supports a workpiece W, and a plurality of adsorption mechanisms 2 arranged on the support 1. The adsorption mechanism 2 includes an elevating body 20 that can move up and down between a first position and a second position above the first position. The elevating body 20 includes an elastically deformable adsorption pad 22 that spreads upward, and has a first opening O1 at its upper end. When the elevating body 20 is at the first position, the first opening O1 can be sealed by the workpiece W, and a pad internal space S1 inside the adsorption pad 22 and a second opening O2 positioned outside the elevating body 20 can be blocked, and when the elevating body 20 is at the second position, the pad internal space S1 communicates with the second opening O2.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a workpiece transport hand used for transporting a thin plate-like workpiece such as a substrate. [Background technology]

[0002] A conveying device for thin plate-like workpieces such as glass substrates used in manufacturing liquid crystal displays and semiconductor wafers used in manufacturing semiconductors is configured with a hand equipped with a vacuum suction function that utilizes negative pressure as an end effector of a robot (see, for example, Patent Document 1). As shown in this document, the hand equipped with a vacuum suction function is provided with a plurality of suction pads that can be selected to apply or not apply negative pressure, facing the upper surface of the hand. A plate-like workpiece placed on the hand is tightly gripped by the suction pads due to the negative pressure applied to the suction pads by driving a pump. In this state, it is possible to convey the workpiece at high speed without it slipping off the hand.

[0003] However, when using a hand equipped with the above-mentioned conventional vacuum suction function, a separate pump for vacuum suction is required. Also, air piping for vacuum suction by the pump and a valve for switching the negative pressure application state must be arranged in the limited space of the robot. Therefore, the configuration for vacuum suction provided on the robot becomes complicated. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2008-132541 A Summary of the Invention [Problem to be solved by the invention]

[0005] The present invention was devised under these circumstances, and its main objective is to provide a work transport hand that is capable of suction and gripping a workpiece without the need for a vacuum suction pump or piping inside the robot. [Means for solving the problem]

[0006] In order to solve the above problems, the present invention employs the following technical means.

[0007] The work transport hand provided by the present invention comprises a support body for supporting a workpiece, and a plurality of suction mechanisms arranged on the support body, the suction mechanism comprising a lifting body that can move up and down between a first position and a second position higher than the first position, the lifting body expanding upward and having a first opening at an upper end, and including an elastically deformable suction pad, when the lifting body is at the first position, the first opening can be sealed by the workpiece, and the space inside the pad of the suction pad can be blocked from a second opening located outside the lifting body, and when the lifting body is at the second position, the space inside the pad and the second opening are connected.

[0008] In a preferred embodiment, the suction mechanism includes a seal portion communicating with both the space within the pad and the second opening, and when the lifting body is in the first position, the space within the pad and the second opening are blocked by the seal portion.

[0009] In a preferred embodiment, the lifting body is located below the suction pad and includes a pad fixing portion to which the suction pad is fixed, the suction mechanism has a guide portion that guides the pad fixing portion so that it can move up and down, and the pad fixing portion has a communication hole formed therein that communicates with both the space within the pad and the seal portion.

[0010] In a preferred embodiment, the pad fixing portion has a first bottom surface facing downward and a first outer peripheral surface located above the first bottom surface and surrounding at least a portion of the first outer peripheral surface in a planar view, the guide portion has a second bottom surface facing the first bottom surface and a first inner peripheral surface located above the second bottom surface and surrounding at least a portion of the first outer peripheral surface, and the sealing portion is interposed between the first bottom surface and the second bottom surface.

[0011] In a preferred embodiment, the support has an upper surface and a recess recessed from the upper surface, and the pad fixing portion is disposed in the recess.

[0012] In a preferred embodiment, the suction pad is made of a soft resin material or a rubber material, and the pad fixing portion and the guide portion are each made of a material harder than the suction pad.

[0013] In a preferred embodiment, the pad fixing portion is made of a metal material. Effect of the Invention

[0014] According to the workpiece transport hand of the present invention, when a workpiece is placed on the support, the space inside the suction pad becomes negative pressure, and the suction pad can suction and grip the workpiece. On the other hand, when a workpiece is placed on a stage or the like, the space inside the pad communicates with the second opening located outside the lifting body, and the suction pad loses its suction force on the workpiece. Therefore, according to the workpiece transport hand of the present invention, it is possible to suction-hold and transport a workpiece without using a vacuum suction pump or associated piping.

[0015] Other features and advantages of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings. [Brief description of the drawings]

[0016] [Figure 1]1 is a plan view showing a first embodiment of a workpiece transport hand according to the present invention. [Diagram 2] FIG. 2 is an enlarged cross-sectional view taken along line II-II in FIG. [Diagram 3] 3 is a cross-sectional view similar to FIG. 2, illustrating a state in which a workpiece is sucked and gripped by a suction mechanism. [Figure 4] FIG. 3 is a cross-sectional view similar to FIG. 2, illustrating the operation. [Diagram 5] FIG. 3 is a cross-sectional view similar to FIG. 2, illustrating the operation. [Figure 6] 2, showing a second embodiment of a workpiece transport hand according to the present invention. FIG. [Figure 7] 7 is a cross-sectional view similar to FIG. 6, illustrating a state in which a workpiece is sucked and held by a suction mechanism. [Figure 8] FIG. 7 is a cross-sectional view similar to FIG. 6, illustrating the operation. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

[0018] 1 and 2 show a first embodiment of a workpiece transport hand according to the present invention. The workpiece transport hand A1 of this embodiment includes a support 1 and a plurality of suction mechanisms 2.

[0019] In this embodiment, the support 1 is a plate on which a workpiece is placed, and extends horizontally integrally from a base member connected to the arm end of a transport robot (not shown). The support 1 has a base 11 and a pair of fork parts 12. The base 11 is fixed to the base member of the transport robot. The pair of fork parts 12 are each connected to the base 11 and extend in a bifurcated shape from the base 11 in a plan view. The material of the support 1 is not particularly limited, but it is made of a highly rigid and lightweight material such as an aluminum alloy, a ceramic material, or a carbon fiber reinforced plastic.

[0020] The plurality of suction mechanisms 2 are disposed spaced apart from each other on the support 1 (the pair of fork portions 12). In this embodiment, four suction mechanisms 2 are provided, with two suction mechanisms 2 disposed separately on the base end sides of the pair of fork portions 12 and the other two suction mechanisms 2 disposed separately on the tip end sides of the pair of fork portions 12. Note that the number and arrangement of the suction mechanisms 2 are not limited to this embodiment and may take various configurations.

[0021] A specific configuration of the suction mechanism 2 will be described with reference to Fig. 2. In this embodiment, the suction mechanism 2 includes a lifting body 20, a guide body 30, and a seal portion 40. The lifting body 20 is supported by a fork portion 12 (support 1) and is movable up and down.

[0022] The lifting body 20 includes a pad fixing portion 21 and a suction pad 22. In this embodiment, the pad fixing portion 21 is generally disk-shaped and has a bottom surface 211, an outer circumferential surface 212, an outward flange 213, a pad recess 214, a seal recess 215, and a communication hole 216.

[0023] The bottom surface 211 is the lower end surface of the pad fixing part 21 and faces downward. The outer peripheral surface 212 is located above the bottom surface 211 and surrounds at least a part of the bottom surface 211 in a plan view. The outward flange 213 extends radially outward from the lower end of the pad fixing part 21 (outer peripheral surface 212). In this embodiment, the outward flange 213 is annular and surrounds the outer peripheral surface 212 in a plan view. The pad recess 214 is recessed downward from the upper surface of the pad fixing part 21 and is a portion for arranging the suction pad 22. The seal part recess 215 is an annular groove recessed from the bottom surface 211 of the pad fixing part 21 and is a portion for arranging the seal part 40. The communication hole 216 is a through hole that leads in the vertical direction from the upper surface of the pad fixing part 21 (the bottom surface of the pad recess 214) to the bottom surface 211, and is formed at the center position of the pad fixing part 21.

[0024] In this embodiment, the suction pad 22 is supported by the pad fixing part 21, and has a base part 221 and a pad part 222. The suction pad 22 is made of a soft resin material or a rubber material. The base part 221 is roughly disk-shaped, and is housed in the pad recess 214. The base part 221 is fixed to the pad fixing part 21 by an appropriate means such as adhesion.

[0025] The pad portion 222 is connected to the upper end of the outer periphery of the base portion 221. The pad portion 222 surrounds the base portion 221 in a plan view. The pad portion 222 is a cylindrical portion that expands upward and has an open upper end. The pad portion 222 has a first opening O1 at its upper end. The pad portion 222 has a relatively small thickness and can easily be elastically deformed.

[0026] A hole 221a is formed at the center of the base portion 221. The hole 221a is a through hole that extends vertically from the upper surface to the lower surface of the base portion 221. The upper end of the hole 221a communicates with an inner space surrounded by the pad portion 222. In this embodiment, the inner space surrounded by the pad portion 222 and the inner space of the hole 221a form an inner space of the suction pad 22 (intra-pad space S1). The lower end of the hole 221a communicates with the communication hole 216 of the pad fixing portion 21.

[0027] The material of the suction pad 22 is not particularly limited, but may be, for example, silicone rubber or fluororubber. The pad fixing portion 21 is made of a material (for example, a hard resin material) harder than the suction pad 22 (pad portion 222). The material of the pad fixing portion 21 is not particularly limited, but may be, for example, polyacetal resin having excellent sliding properties and abrasion resistance.

[0028] A recess 13 having, for example, a circular shape is formed in the fork portion 12 (support 1). The recess 13 is recessed downward from the upper surface 12a of the fork portion 12. In this embodiment, the pad fixing portion 21 is disposed in this recess 13. In this embodiment, the recess 13 has a recess bottom surface 131 and a recess inner peripheral surface 132. The recess bottom surface 131 faces upward and faces the bottom surface 211 of the pad fixing portion 21. The recess inner peripheral surface 132 is connected to the outer periphery of the recess bottom surface 131 and is located above the recess bottom surface 131.

[0029] In this embodiment, the guide body 30 is annular and has a cylindrical portion 31. The guide body 30 has, for example, an outward flange extending radially outward from the upper end of the cylindrical portion 31, and is fixed to the fork portion 12 (support 1) in a state in which the outward flange overlaps the upper surface 12a (fork portion 12) around the recess 13. The cylindrical portion 31 is inserted into the recess inner circumferential surface 132 of the recess 13. The vertical dimension of the cylindrical portion 31 in the recess 13 is smaller than the vertical dimension of the recess 13. A guide surface 311 is formed on the inner circumference of the cylindrical portion 31. The guide surface 311 surrounds a part of the outer circumferential surface 212 of the pad fixing portion 21. The inner diameter dimension of the guide surface 311 is slightly larger than the outer diameter dimension of the outer circumferential surface 212 of the pad fixing portion 21. As a result, the lifting body 20 (pad fixing part 21) can move up and down while being guided by the guide body 30 (guide surface 311 of the cylindrical part 31). A small gap is formed between the guide surface 311 (guide body 30) and the outer circumferential surface 212 (pad fixing part 21). In this embodiment, the gap between the guide surface 311 and the outer circumferential surface 212 corresponds to a second opening O2 located outside the lifting body 20. As can be seen from FIG. 2, the cylindrical part 31 overlaps with the outward flange 213 of the pad fixing part 21 in a plan view. As a result, the upper end of the up and down stroke of the lifting body 20 (pad fixing part 21) is determined by the outward flange 213 of the pad fixing part 21 abutting against the lower surface of the cylindrical part 31.

[0030] The guide body 30 is made of, for example, a material (such as a hard resin material) harder than the suction pad 22 (pad portion 222). The material of the guide body 30 is not particularly limited, but is made of, for example, polyacetal resin having excellent sliding properties and abrasion resistance.

[0031] In this embodiment, the seal portion 40 is disposed in the seal portion recess 215 of the pad fixing portion 21. The seal portion 40 is annular in plan view, and has a block portion 41 and an extension piece 42. A large portion of the block portion 41 is housed in the seal portion recess 215. The extension piece 42 extends from the lower end of the block portion 41, and has a thin lip shape. In the illustrated example, a pair of extension pieces 42 extend from both the lower end inner periphery and the lower end outer periphery of the block portion 41. The seal portion 40 is made of a soft resin material or a rubber material.

[0032] In this embodiment, the seal portion 40 is interposed between the bottom surface 211 of the pad fixing portion 21 and the recess bottom surface 131 of the recess 13. As shown in FIG. 2, the seal portion 40 communicates with both the pad inner space S1 inside the suction pad 22 and the second opening O2 located outside the lifting body 20. When the lifting body 20 (pad fixing portion 21) is at the lower end position of its up-down movement stroke, the seal portion 40 comes into close contact with the recess bottom surface 131 of the recess 13, blocking the gap between the bottom surface 211 and the recess bottom surface 131. As a result, the lower end of the up-down movement stroke of the lifting body 20 (pad fixing portion 21) is determined by the recess bottom surface 131. Furthermore, when the sealing portion 40 is in close contact with the bottom surface 131 of the recess 13 to seal the space between the bottom surface 211 and the bottom surface 131 of the recess, the pad space S1 inside the suction pad 22 is blocked from the gap (second opening O2) between the guide body 30 and the pad fixing portion 21.

[0033] In this embodiment, the bottom surface 211 of the pad fixing portion 21 corresponds to the "first bottom surface" of the present invention, and the outer peripheral surface 212 of the pad fixing portion 21 corresponds to the "first outer peripheral surface" of the present invention. The recess bottom surface 131 of the recess 13 corresponds to an example of the "second bottom surface" of the present invention, and the guide surface 311 of the guide body 30 corresponds to an example of the "first inner peripheral surface" of the present invention.

[0034] Next, the operation of this embodiment will be described.

[0035] When a thin plate-like workpiece is transported by the workpiece transport hand A1, the workpiece is supported by the support body 1. Here, as shown in Fig. 3, the workpiece W is placed on the pad portion 222 (suction pad 22) of the suction mechanism 2, and the lifting body 20 (pad fixing portion 21) is at the lowest position due to the weight of the workpiece W. The pad portion 222 expands substantially horizontally, and the pad inner space S1 inside the suction pad 22 is significantly reduced, and the first opening O1 of the pad portion 222 is sealed by the workpiece W.

[0036] In addition, the seal portion 40 arranged at the lower end of the pad fixing portion 21 is in close contact with the bottom surface 131 of the recess, and blocks the gap between the bottom surface 211 and the bottom surface 131 of the recess. At this time, the seal portion 40 blocks the space S1 inside the suction pad 22 and the gap (second opening O2) between the guide body 30 and the pad fixing portion 21. The communication hole 216 formed in the pad fixing portion 21 communicates with the space S1 inside the pad, and also communicates with the space between the bottom surface 211 and the bottom surface 131 of the recess. As a result, a sealed space is formed by the space S1 inside the pad, the communication hole 216, and the space surrounded by the bottom surface 211, the bottom surface 131 of the recess, and the seal portion 40, and the sealed space is in a state where the pressure is reduced to less than atmospheric pressure (negative pressure state). Therefore, in the state shown in FIG. 3, the workpiece W is suction-held by the pad portion 222 (suction mechanism 2), and can be moved horizontally and transported. As shown in FIG. 3, the position where the lift body 20 (pad fixing portion 21) is lowered to the lowest position corresponds to the "first position" of the present invention.

[0037] Next, for example, when placing the workpiece W on a destination stage (not shown), the support 1 (fork portion 12) is lowered as shown in FIG. 4, and the workpiece W is transferred to a stage (not shown). Here, even when the support 1 starts to be lowered, the pad portion 222 continues to be attached to the workpiece W. Therefore, the lifting body 20 (pad fixing portion 21) is positioned relatively higher than the support 1, as compared to the case shown in FIG. 3. Then, the seal portion 40 moves away from the bottom surface 131 of the recess, and the pad inner space S1 inside the suction pad 22 communicates with the gap (second opening O2) between the guide body 30 and the pad fixing portion 21.

[0038] In a state where the space S1 in the pad communicates with the gap (second opening O2) between the guide body 30 and the pad fixing part 21, air flows in from the second opening O2 and flows into the communication hole 216 and the space S1 in the pad. Then, as shown in FIG. 5, the space S1 in the pad returns to an atmospheric pressure state, and the pad part 222 (suction pad 22) loses the suction force of the workpiece W. In the state shown in FIG. 5, the space S1 in the pad communicates with the second opening O2, and the lifting body 20 (pad fixing part 21) is located relatively higher with respect to the support body 1 compared to the case shown in FIG. 3. In the state shown in FIG. 4 and FIG. 5, the lifting body 20 (pad fixing part 21) is in the "second position" of the present invention. After that, the pad part 222 leaves the workpiece W, and the lifting body 20 (pad fixing part 21) falls into the recess 13 of the support body 1 by its own weight, returning to the state shown in FIG. 2.

[0039] The workpiece transport hand A1 includes a support 1 and a plurality of suction mechanisms 2 arranged on the support 1. The suction mechanism 2 includes a lifting body 20, which is movable up and down between a first position and a second position above the first position. The lifting body 20 includes a suction pad 22. The suction pad 22 (pad portion 222) expands upward, has a first opening O1 at its upper end, and is elastically deformable. When the lifting body 20 is at the first position, the first opening O1 is sealed by the workpiece W, and an inner-pad space S1 inside the suction pad 22 is blocked from a second opening O2 located outside the lifting body 20. On the other hand, when the lifting body 20 is at the second position, the inner-pad space S1 and the second opening O2 are in communication with each other.

[0040] According to this configuration, when the workpiece W is placed on the support 1, the pad inner space S1 inside the suction pad 22 becomes negative pressure, and the pad portion 222 (suction pad 22, suction mechanism 2) can suction and grip the workpiece W. On the other hand, when the workpiece W is placed on a stage or the like, the pad inner space S1 and the second opening O2 communicate with each other, and the pad portion 222 (suction pad 22, suction mechanism 2) loses its suction force on the workpiece W. Therefore, according to the workpiece transport hand A1 of this embodiment, it is possible to suction-hold and transport the workpiece W without using a vacuum suction pump or associated piping.

[0041] The suction mechanism 2 includes a seal portion 40. The seal portion 40 communicates with both the space within the pad S1 and the second opening O2. When the lifting body 20 is in the first position, the space within the pad S1 and the second opening O2 are blocked by the seal portion 40. With such a configuration including the seal portion 40, when the lifting body 20 is in the first position, the space within the pad S1 and the second opening O2 can be appropriately blocked. Therefore, the negative pressure state of the space within the pad S1 is appropriately maintained, and as a result, the workpiece W can be more reliably suction-held by the suction pad 22.

[0042] The lifting body 20 includes a pad fixing part 21 located below the suction pad 22, and the suction pad 22 is fixed to this pad fixing part 21. The suction mechanism 2 includes a recess bottom surface 131 and a guide surface 311 (guide part) for guiding the pad fixing part 21 so that it can move up and down. A communication hole 216 is formed in the pad fixing part 21, and the communication hole 216 communicates with both the pad internal space S1 and the seal part 40. With this configuration, the lifting body 20 can be moved up and down appropriately, and the movement of the lifting body 20 is stabilized.

[0043] The pad fixing part 21 has a bottom surface 211 (first bottom surface) facing downward, and an outer peripheral surface 212 (first outer peripheral surface) located above the bottom surface 211 and surrounding at least a part of the bottom surface 211 (first bottom surface) in a plan view. In this embodiment, the guide part has a recessed bottom surface 131 (second bottom surface) facing the bottom surface 211, and a guide surface 311 (first inner peripheral surface) located above the recessed bottom surface 131 and surrounding a part of the outer peripheral surface 212. The seal part 40 is interposed between the bottom surface 211 and the recessed bottom surface 131. With this configuration, the vertical movement of the lifting body 20 is stabilized, and when the lifting body 20 starts to move upward relative to the support body 1 from a state in which it is in the first position, the pad inner space S1 and the second opening O2 are quickly communicated. Therefore, the suction pad 22 is prevented from continuing to suction the workpiece W inappropriately.

[0044] The fork portion 12 (support 1) has a recess 13 recessed from an upper surface 12a. The pad fixing portion 21 is disposed in the recess 13. With this configuration, the overall vertical dimension of the support 1 and the suction mechanism 2 disposed on the support 1 can be reduced.

[0045] Fig. 6 shows a second embodiment of the workpiece transport hand according to the present invention. In the drawings following Fig. 6, elements that are the same as or similar to those of the workpiece transport hand A1 of the above embodiment are given the same reference numerals as those of the above embodiment, and descriptions thereof will be omitted as appropriate.

[0046] The workpiece transport hand A2 shown in FIG. 6 does not include a guide body 30, as compared with the workpiece transport hand A1 of the above embodiment, and this point is a major difference from the workpiece transport hand A1. In addition, the pad fixing part 21 does not have an outward flange 213, and the outer peripheral surface 212 is connected to the outer peripheral edge of the bottom surface 211. As in the above embodiment, the pad fixing part 21 is disposed in the recess 13. The recess inner peripheral surface 132 of the recess 13 surrounds the outer peripheral surface 212 of the pad fixing part 21. The inner diameter dimension of the recess inner peripheral surface 132 is slightly larger than the outer diameter dimension of the outer peripheral surface 212 of the pad fixing part 21. As a result, the lifting body 20 (pad fixing part 21) can move up and down while being guided by the recess inner peripheral surface 132. A small gap is formed between the recess inner peripheral surface 132 (recess 13) and the outer peripheral surface 212 (pad fixing part 21). In this embodiment, the gap between the recess inner circumferential surface 132 and the outer circumferential surface 212 corresponds to a second opening O2 located outside the lift body 20.

[0047] When the lifting body 20 (pad fixing part 21) is at the lower end position of its up-down stroke, the seal part 40 comes into close contact with the recess bottom surface 131 of the recess 13 and blocks the gap between the bottom surface 211 and the recess bottom surface 131. As a result, the lower end of the up-down stroke of the lifting body 20 (pad fixing part 21) is determined by the recess bottom surface 131. When the seal part 40 comes into close contact with the recess bottom surface 131 of the recess 13 and blocks the gap between the bottom surface 211 and the recess bottom surface 131, the pad intra-space S1 inside the suction pad 22 is blocked from the gap (second opening O2) between the recess 13 and the pad fixing part 21.

[0048] In this embodiment, the pad fixing portion 21 is made of, for example, a metal material. The pad fixing portion 21 made of a metal material is heavier than the pad fixing portion 21 made of a resin material.

[0049] In this embodiment, the bottom surface 211 of the pad fixing portion 21 corresponds to the "first bottom surface" of the present invention, and the outer peripheral surface 212 of the pad fixing portion 21 corresponds to the "first outer peripheral surface" of the present invention. The recess bottom surface 131 of the recess 13 corresponds to an example of the "second bottom surface" of the present invention, and the recess inner peripheral surface 132 of the recess 13 corresponds to an example of the "first inner peripheral surface" of the present invention.

[0050] Next, the operation of this embodiment will be described.

[0051] When a thin plate-like workpiece is transported by the workpiece transport hand A2, the workpiece is supported by the support body 1. Here, as shown in Fig. 7, the workpiece W is placed on the pad portion 222 (suction pad 22) of the suction mechanism 2, and the lifting body 20 (pad fixing portion 21) is at the lowest position due to the weight of the workpiece W. The pad portion 222 expands substantially horizontally, and the pad inner space S1 inside the suction pad 22 is significantly reduced, and the first opening O1 of the pad portion 222 is sealed by the workpiece W.

[0052] In addition, the seal portion 40 arranged at the lower end of the pad fixing portion 21 is in close contact with the bottom surface 131 of the recess, and blocks the gap between the bottom surface 211 and the bottom surface 131 of the recess. At this time, the seal portion 40 blocks the space S1 inside the suction pad 22 and the gap (second opening O2) between the recess 13 and the pad fixing portion 21. The communication hole 216 formed in the pad fixing portion 21 communicates with the space S1 inside the pad, and also communicates with the space between the bottom surface 211 and the bottom surface 131 of the recess. As a result, a sealed space is formed by the space S1 inside the pad, the communication hole 216, and the space surrounded by the bottom surface 211, the bottom surface 131 of the recess, and the seal portion 40, and the sealed space is in a state where the pressure is reduced to less than atmospheric pressure (negative pressure state). Therefore, in the state shown in FIG. 7, the workpiece W is suction-held by the pad portion 222 (suction mechanism 2), and can be moved horizontally and transported. As shown in FIG. 7, the position where the lift body 20 (pad fixing portion 21) is lowered to the lowest position corresponds to the "first position" of the present invention.

[0053] For example, when placing the workpiece W on a destination stage (not shown), the support 1 (fork portion 12) is lowered while the workpiece W is transferred to a stage (not shown). Here, even when the support 1 starts to be lowered, the pad portion 222 continues to be attached to the workpiece W. Therefore, the lifting body 20 (pad fixing portion 21) is positioned relatively higher than the support 1 compared to the case shown in FIG. 7. Then, the seal portion 40 moves away from the bottom surface 131 of the recess, and the pad inner space S1 inside the suction pad 22 communicates with the gap (second opening O2) between the recess 13 and the pad fixing portion 21.

[0054] In a state where the space S1 in the pad communicates with the gap (second opening O2) between the recess 13 and the pad fixing part 21, air flows in from the second opening O2 and flows into the communication hole 216 and the space S1 in the pad. Then, as shown in FIG. 8, the space S1 in the pad returns to an atmospheric pressure state, and the pad part 222 (suction pad 22) loses the suction force of the workpiece W. In the state shown in FIG. 8, the space S1 in the pad communicates with the second opening O2, and the lifting body 20 (pad fixing part 21) is located relatively higher with respect to the support body 1 compared to the case shown in FIG. 7. In the state shown in FIG. 8, the lifting body 20 (pad fixing part 21) is in the "second position" of the present invention. After that, the pad part 222 leaves the workpiece W, and the lifting body 20 (pad fixing part 21) falls into the recess 13 of the support body 1 by its own weight, returning to the state shown in FIG. 6.

[0055] The workpiece transport hand A2 includes a support 1 and a plurality of suction mechanisms 2 arranged on the support 1. The suction mechanism 2 includes a lifting body 20, which is movable up and down between a first position and a second position above the first position. The lifting body 20 includes a suction pad 22. The suction pad 22 (pad portion 222) expands upward, has a first opening O1 at its upper end, and is elastically deformable. When the lifting body 20 is at the first position, the first opening O1 is sealed by the workpiece W, and the pad space S1 inside the suction pad 22 is blocked from the second opening O2 located outside the lifting body 20. On the other hand, when the lifting body 20 is at the second position, the pad space S1 and the second opening O2 are in communication with each other.

[0056] According to this configuration, when the workpiece W is placed on the support 1, the pad space S1 inside the suction pad 22 becomes negative pressure, and the pad portion 222 (suction pad 22, suction mechanism 2) can suction and hold the workpiece W. On the other hand, when the workpiece W is placed on a stage or the like, the pad space S1 and the second opening O2 communicate with each other, and the pad portion 222 (suction pad 22, suction mechanism 2) loses its suction force for the workpiece W. Therefore, according to the workpiece transport hand A2 of this embodiment, it is possible to suction-hold and transport the workpiece W without using a vacuum suction pump or associated piping.

[0057] When the lifting body 20 moves upward relative to the support 1 from a state in which the suction mechanism 2 suction-holds the workpiece W and the lifting body 20 is in the first position, the space inside the pad S1 and the second opening O2 communicate with each other. In this embodiment, the pad fixing part 21 is made of a metal material and is relatively heavy. With this configuration, after the space inside the pad S1 and the second opening O2 communicate with each other, the suction pad 22 is quickly separated from the workpiece W by the weight of the pad fixing part 21. Therefore, the efficiency of transporting the workpiece W can be improved. In addition, within the scope of the same configuration as the workpiece transport hand A1 of the above embodiment, the same effects as those of the above embodiment are achieved.

[0058] Although an embodiment of the present invention has been described above, the scope of the present invention is not limited to the above-described embodiment, and all modifications within the scope of the matters described in each claim are all included in the scope of the present invention.

[0059] In the above embodiment, the seal portion 40 is disposed on the bottom surface 211 side of the pad fixing portion 21, but the seal portion 40 may be disposed on the bottom surface 131 side of the recess 13. In the above embodiment, the seal portion 40 has a lip-shaped extension piece 42, but the specific configuration of the seal portion can be changed in various ways. For example, the seal portion may be formed by an O-ring or a plate-shaped seal member. When the seal portion is disposed on the bottom surface 131 side of the recess, the seal portion does not have to be annular. In the above embodiment, the seal portion 40 is disposed between the bottom surface 211 of the pad fixing portion 21 and the bottom surface 131 of the recess 13, but the present invention is not limited to this. For example, the seal portion 40 may be disposed between the outer peripheral surface 212 of the pad fixing portion 21 and the inner peripheral surface 132 of the recess 13. [Explanation of symbols]

[0060] A1, A2: workpiece transport hand, 1: support, 12a: upper surface (upper surface of support), 13: recess, 131: recess bottom surface (second bottom surface), 132: recess inner peripheral surface (first inner peripheral surface), 2: suction mechanism, 21: pad fixing portion, 211: bottom surface (second bottom surface), 212: outer peripheral surface (first outer peripheral surface), 216: communication hole, 22: suction pad, 30: guide body, 311: guide surface (first inner peripheral surface), 40: seal portion, O1: first opening, O2: second opening, S1: space inside pad, W: workpiece

Claims

1. A support for supporting a workpiece; a plurality of suction mechanisms disposed on the support; the suction mechanism includes a lifting body that is movable up and down between a first position and a second position higher than the first position, the lifting body includes an elastically deformable suction pad that expands upward and has a first opening at an upper end; when the lifting body is at the first position, the first opening can be sealed by the work, and a space inside the suction pad can be blocked from a second opening located outside the lifting body; A workpiece transport hand, wherein when the lifting body is in the second position, the space within the pad communicates with the second opening.

2. the suction mechanism includes a seal portion communicating with both the space within the pad and the second opening, The workpiece transport hand according to claim 1 , wherein when the lifting body is at the first position, the space within the pad and the second opening are blocked off by the seal portion.

3. the lifting body is located below the suction pad and includes a pad fixing portion to which the suction pad is fixed, The suction mechanism includes a guide portion that guides the pad fixing portion so that the pad fixing portion can move up and down. The workpiece transport hand according to claim 2 , wherein the pad fixing portion is formed with a communication hole communicating with both the space within the pad and the seal portion.

4. The pad fixing portion has a first bottom surface facing downward, and a first outer circumferential surface located above the first bottom surface and surrounding at least a portion of the first bottom surface in a plan view, the guide portion has a second bottom surface facing the first bottom surface, and a first inner circumferential surface located above the second bottom surface and surrounding at least a portion of the first outer circumferential surface, The workpiece transport hand according to claim 3 , wherein the seal portion is interposed between the first bottom surface and the second bottom surface.

5. the support has a support upper surface and a recess recessed from the support upper surface, The workpiece transport hand according to claim 3 , wherein the pad fixing portion is disposed in the recess.

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