TW201345812A - Suction chuck and trasfering apparatus - Google Patents

Abstract

A suction chuck and a transferring apparatus are provided to move a structure to the arbitrary position and prevent the deformation or damage of the structure at the same time since the vibration or deformation of the thin plate formed structure is suppressed and sucked, and maintained. CONSTITUTION: A suction chuck (10) comprises a main body (11), an opposite surface (31), a plurality of outlets (41), and a plurality of exhaust cavities (42) of the thin plate form. The exhaust cavities are positioned around the outlets so as to be opened to the opposite surface and formed for penetrating the main body in the thickness direction. Each outlet is formed as a cylindrical space, and comprises 3 nozzle flow paths (44) opened towards inside the space. Compressed gas gushes from each nozzle flow path along the inner wall of the cylindrical space.

Description

Attracting fixture and transfer device

The present invention mainly relates to a structure of a suction jig that conveys and holds a workpiece in a non-contact manner.

There is a non-contact conveyance device (for example, refer to Patent Document 1), in order to move a thin flat workpiece (a thin plate workpiece) such as a solar cell wafer or a fuel cell unit or an electrode or a separator of a secondary battery. Loaded with a white effort fixture, the fixture is a white effort effect.

The non-contact conveying device described in Patent Document 1 has a structure in which air is ejected into a swirling flow forming body (suction element) formed into a hollow cylindrical shape, and a swirling flow is formed inside the swirling flow forming body. Since the swirling flow flows out from the swirling flow forming body to the high-speed flow, the end surface of the swirling flow forming body and the object to be conveyed (wafer) become a negative pressure. Thereby, the object to be conveyed can be sucked and held in a non-contact manner. According to the patent document 1, the air injected into the swirling flow forming body is rectified along the inner peripheral surface to form a swirling flow, and the swirling flow is smoothly formed without the passage resistance, thereby improving energy efficiency and saving. Energyization.

In the transfer device that sucks and holds the thin plate-shaped workpiece (object to be transported), it is preferable to uniformly apply the suction force (negative pressure) to the workpiece. Working When the attraction of the workpiece is uneven, vibration and deformation occur in the workpiece. From this point of view, it is considered to minimize the size of the attraction member for generating the attraction force, and it is preferable to increase the number of the attraction members per unit area.

In the non-contact conveying device described in Patent Document 1, the swirling flow forming body (suction element) formed in a hollow cylindrical shape has a fluid introduction port, a fluid passage, a discharge port, and the like, so that it is difficult to form the swirling flow forming body. miniaturization. Therefore, it is difficult to increase the number of swirling flow formation bodies per unit area. Patent Document 1 also discloses that a plurality of concave portions and fluid passages are formed in a base body of a thin plate-shaped non-contact conveying device, and a swirling flow is generated in an internal space of the concave portion. However, since the configuration is such that the recesses are disposed on the two wrist portions, the attraction force acting on the workpiece is generated only in the portions of the two wrist portions. Therefore, in this configuration, the attraction force cannot be uniformly applied to the entire surface of the workpiece.

Therefore, the applicant of the present application has proposed the Japanese Patent Application No. 2011-94215 of the Japanese Patent Application, the attraction jig 9 shown in Figs. 11 and 12. This is a flat-shaped suction jig body in which metal plate portions are stacked, and an opposing surface 31 that directly faces the workpiece is formed, and a plurality of air ejection ports that are open to the opposing surface 31 are attracted. The elements 41 are arranged in an array. Inside the main body of the suction jig 9, a nozzle flow path 44 that discharges compressed air inside the air ejection port 41 is formed. As shown in Figs. 11 and 12, the nozzle flow path 44 is formed in two with respect to one air ejection port 41. The two nozzle flow paths 44 are 180 degrees out of phase with each other, and an opening is formed in the inner wall of the air ejection port 41. By from When the nozzle flow path 44 ejects air, the air can flow along the inner wall surface of the air ejection port 41. The air flowing along the inner wall surface of the air ejection port 41 flows out from the air ejection port 41 at a high speed, thereby generating an attractive force.

The air ejection port 41, the nozzle flow path 44, and the like can be formed by a method such as etching or punching on the metal plate portion, and it is easy to downsize and dense. For example, in the suction jig 9 of Fig. 11, the diameter of the air ejection port 41 is made, for example, 3 mm. In this way, the air ejection port 41 can be made extremely small, so that the number of suction elements (air ejection ports 41) arranged per unit area can be increased. Further, as shown in Fig. 11, by arranging the air ejection ports 41 in a plurality of arrays in an array, the suction force can be uniformly applied to the workpiece in a uniform manner, and vibration and deformation of the workpiece can be prevented.

In the suction jig 9 shown in Fig. 11, a plurality of exhaust holes 42 for discharging air are formed in the opposing surface 31. The exhaust hole 42 is formed to penetrate the main body of the suction jig 9 in the thickness direction. The air ejected from the air ejection port 41 is discharged through the exhaust hole 42.

[Previous Technical Literature] [Patent Document]

[Patent Document 1] Japanese Patent No. 3981241

The non-contact conveying device disclosed in Patent Document 1 attracts an element (back The periphery of the swirling flow forming body becomes a space. In this configuration, the air ejected from the attraction member is quickly discharged toward the space. Therefore, in the configuration of Patent Document 1, the flow of the air ejected from the attraction member is not considered to be stagnant.

On the other hand, in the suction jig 9 of the comparative example shown in FIG. 11, the air discharged from each of the air ejection ports 41 flows into the exhaust hole 42 and is discharged from the exhaust hole 42. If the air does not flow smoothly from the air ejection port 41 to the exhaust hole 42, the flow velocity is lowered, and a decrease in attraction force is generated. Therefore, it is important that the suction jig 9 of the configuration of Fig. 11 allows air to smoothly flow from the air ejection port 41 to the exhaust hole 42.

Based on the above viewpoints, the inventors of the present invention repeatedly performed the results of analysis of experiments and computer simulations, and found the following problems.

First, in Fig. 13, the result of computer simulation by the flow of the air ejected from the air ejection port 41 of the suction jig 9 of the comparative example shown in Fig. 11 is shown. This computer simulation was obtained by setting the diameter of the air ejection port 41 to 3 mm. ΔZ in Fig. 13 indicates the interval between the opposing surface 31 of the suction jig 9 and the workpiece. It can be seen that the suction jig 9 is gradually approaching with respect to the workpiece, and the flow of the air changes. The state in which ΔZ = 0.1 mm is the most stable state, and in this state, the workpiece is sucked and held by the suction jig 9.

According to the disclosure of Patent Document 1, the air that has been injected into the swirling flow forming body provided in the structure of Patent Document 1 is rectified along the inner peripheral surface to generate a swirling flow. As can be understood from the results of the computer simulation of Fig. 13, the suction jig 9 of the comparative example is ejected from the nozzle flow path 44. The gas is ejected to the outside without being swirled in the air ejection port 41. This should be because the suction jig 9 (Fig. 11) of the comparative example is such that the air ejection port 41 is formed to be extremely small (diameter: 3 mm), and inside the air ejection port 41, the swirling component of the air flow is extremely small, and the air flow is Not fully swirled. When the air is not sufficiently swirled inside the air ejection port 41, the air ejected from the nozzle flow path 44 flows out from the air ejection port 41 substantially without being dispersed. As a result, the direction in which the air from the air ejection port 41 is ejected is concentrated in a specific direction. In the case of the suction jig of the comparative example shown in Fig. 13, since the two nozzle flow paths 44 are provided in the respective air ejection ports 41, the direction of the air flowing out from the air ejection ports 41 is concentrated in both directions.

As shown in the comparative example (a) of Fig. 13, the air ejected from the air ejection port 41 in both directions is drawn to the exhaust hole 42 by the flow path which is greatly detoured. In the case of the comparative example (a) of Fig. 13, in particular, in the case where ΔZ = 0.3 mm and ΔZ = 0.2 mm, the air circulated abruptly. When ΔZ = 0.2 mm and ΔZ = 0.1 mm, it can be seen that a large loop-like flow occurs and the flow of air stagnates.

According to the simulation performed by the inventors of the present invention, it can be understood that the suction jig 9 of the comparative example of Fig. 11 does not smoothly flow the air. By the air not flowing smoothly, it may cause a decrease in attractiveness. Therefore, the inventors of the present invention obtained the pressure distribution around the air ejection port 41 shown in the comparative example (a) of Fig. 13 by computer simulation. This result is shown in the comparative example (a) of Fig. 14. Fig. 14 shows a pressure distribution in a state of ΔZ = 0.1 mm (a state in which the suction jig 9 sucks and holds the workpiece). The shade of the color in Figure 14 indicates the size of the attraction, and the thicker the part, the rebound force The stronger the repulsive force. The lighter (whiter) part of the color indicates attractiveness, and the middle gray indicates atmospheric pressure (=attractive force is zero). The vicinity of the nozzle flow path 44 is the portion where the flow velocity is the fastest, and the inside of the air discharge port 41 generates a negative pressure by swirling the jet flow along the cylindrical surface, so that the vicinity must become an attractive force. Since the exhaust hole 42 communicates with the atmospheric pressure, the force generated in this portion is substantially zero. Therefore, the distribution of the repulsive force in the region other than the air ejection port 41 and the exhaust hole 42 (the region around the air ejection port 41) becomes a problem.

According to the simulation result of Fig. 14, it is understood that the rebound force of the periphery of the air ejection port 41 is uneven. In the suction jig 9 of the comparative example, the air ejection port 41 has a very small body, and the air ejection ports 41 are arranged in an array. Therefore, compared with the structure of Patent Document 1, the attraction force and the repulsive force can be distributed at a fine pitch. And the role. Therefore, even if the repulsive force is uneven around the air ejection port 41, it can be said that a uniform repulsive force acts on the workpiece from the entire structure of the suction jig 9 as compared with the structure of Patent Document 1. However, in the case where a thin wafer-shaped workpiece is to be processed, the distribution of the biasing repulsive force around the air ejection port 41 may cause deformation or vibration of the workpiece. Therefore, even such a slight unevenness of the rebound force has room for improvement.

The inventors of the present invention considered that the above-mentioned biasing force is biased because the air does not flow smoothly from the air ejection port 41 to the exhaust hole 42, and the air stagnates. It is considered that the stagnation of the air can be improved by optimizing the position of the vent hole 42. In Fig. 13, as a comparative example (b), and in Fig. 14, as a comparative example (b), the position of the exhaust hole 42 can be displayed. The result of computer simulation when the most appropriate.

As understood from the results of the computer simulation, by optimizing the position of the vent hole 42, the air flow can be made slightly smoother than (Comparative Example (b)) and before the most appropriate (Comparative Example (a)). And also slightly improved the bias of the rebound. However, as shown in the comparative example (b) of Fig. 13, even if the position of the vent hole is optimized, a loop-like flow of air remains, and the stagnation of the air cannot be completely cancelled. Also from the comparative example (b) of Fig. 14, it is impossible to completely cancel the bias of the repulsive force.

In the actual suction jig 9, there is a problem that it is not necessary to form the exhaust hole 42 at the most appropriate position. Inside the suction jig 9, it is necessary to form a flow path for supplying compressed air to the air ejection port 41, and it is necessary to avoid the flow path to form the exhaust hole 42. On the other hand, when the vent hole 42 is to be formed at the most appropriate position, the degree of freedom in designing the suction jig 9 is lowered. Therefore, for example, it is difficult to perform free design in which an inductor or the like is disposed at an arbitrary position.

In the idea of optimizing the position of the vent hole 42, it is not sufficient or impossible to release the bias of the repulsive force around the air ejection port 41. Therefore, a structure capable of effectively uniformizing the repulsive force around the air ejection port 41 is required.

The present invention has been made in view of the above circumstances, and its main object is to provide a suction jig that allows air to flow smoothly regardless of the position of the vent hole, thereby releasing the bias of the repulsive force.

The problem to be solved by the present invention is as described above, and the solution to the problem will be described next. Means and their effects.

From the viewpoint of the present invention, the following structure of the suction jig that sucks the thin flat workpiece and is held in a non-contact state is provided. That is, the suction jig includes a flat body, a facing surface, a plurality of air ejection ports, and a plurality of vent holes. Inside the main body, a flow path of compressed gas is formed. The opposing surface is a surface of the main body facing the workpiece side. The air ejection port is opened to the opposing surface in order to eject the compressed gas supplied from the flow path. The exhaust hole is formed to open to the opposite surface around the air ejection port, and penetrates the main body in a thickness direction. Each of the air ejection ports is formed in a cylindrical space, and has a nozzle flow path in which three faces open to the inside of the space, and each nozzle flow path discharges compressed gas toward a direction along the inner wall of the cylindrical space.

In this manner, by supplying the compressed gas into the discharge port from the three nozzle flow paths, the flow of the compressed gas discharged from the discharge port is dispersed in three directions. Since the flow of the compressed gas is dispersed in three directions, the influence of the position of the vent hole on the flow of the compressed air becomes small, and as a result, the vent hole can be freely arranged to increase the degree of design freedom. Moreover, since the flow distribution of the compressed air is dispersed to uniformize the pressure distribution, vibration and deformation of the workpiece can be prevented. By increasing the number of nozzle flow paths, the flow rate of the compressed gas per nozzle flow path is reduced, so that the impact of the workpiece can be reduced by the air ejection.

In the above-described suction jig, the openings of the three nozzle flow paths are preferably formed at equal intervals in the circumferential direction of the discharge port.

By supplying the compressed gas into the discharge port from the nozzle flow paths having the openings at equal intervals, the compressed gas discharged from the discharge port can be uniformly dispersed in three directions.

In the suction jig described above, the longitudinal direction of the nozzle flow path is formed to be parallel to the opposing surface.

Thereby, the compressed gas discharged from the discharge port can be smoothly flowed along the opposing surface.

In the suction jig described above, at least three of the vent holes in the vicinity of the discharge port are formed in a concentric circle around the discharge port.

Thereby, the compressed gas discharged from the discharge port in three directions can be smoothly exhausted from the exhaust hole.

In the suction jig described above, the exhaust holes in the vicinity of the discharge port are formed at equal intervals on the concentric circles.

Thereby, the compressed gas can be uniformly dispersed and flowed to the exhaust hole, so that the pressure distribution around the discharge port can be more equalized.

In the above-described suction jig, the nozzle flow path is formed such that the flow direction of the compressed gas around the axis of the discharge port in the internal space of the arbitrary discharge port and the other discharge port formed in the vicinity of the discharge port are opposite direction.

Thereby, the torque generated by the compressed gas that swirls in the discharge port is eliminated, and the rotation of the workpiece sucked and held by the suction jig can be prevented. Further, if the number of the discharge ports whose flow direction is the clockwise direction is the same as the number of the discharge ports whose flow direction is the counterclockwise direction (reverse direction), the rotational force of each attraction element with respect to the rotation center of the workpiece The sum of the moments becomes zero, and the rotation of the workpiece held by the suction jig can be more effectively prevented. Further, one or more restriction members that are in contact with the side surface of the workpiece sucked and held by the suction jig to prevent rotation thereof may be provided around the suction jig.

According to another aspect of the present invention, a transfer device including the above-described suction jig and a parallel mechanism that can move the suction jig three-dimensionally within a predetermined range is provided.

That is to say, by the parallel mechanism, the workpiece sucked and held by the suction jig can be freely moved three times. According to the suction jig of the present invention, the thin flat workpiece can be prevented from being vibrated or deformed and sucked and held. Therefore, the above-described transfer device can prevent the workpiece from being deformed or damaged, and the workpiece can be moved to an arbitrary position. .

1‧‧‧Transporting robotic arm (transfer device)

10‧‧‧Attraction fixture

11‧‧‧ Subject

31‧‧‧relative

41‧‧‧Air outlet (spray outlet)

42‧‧‧through holes

44‧‧‧Nozzle flow path

Fig. 1 is a perspective view of a transfer robot having a suction jig according to an embodiment of the present invention.

Fig. 2 is a perspective view mainly showing the lower side (opposing surface) of the suction jig.

Figure 3 is a schematic cross-sectional view of the attraction jig.

Fig. 4 is a perspective view showing the penetration of the nozzle flow path.

Fig. 5 is a plan view showing the opposing faces of the suction jig.

Fig. 6 is a plan view showing a state in which air is ejected from an air ejection port.

Fig. 7(a) is a flow path of the air of the suction jig of the embodiment. A display of the results obtained by computer simulation. (b) is a display diagram showing the result of performing the same simulation by changing the position of the vent hole.

Fig. 8(a) is a view showing a result obtained by computer simulation of the pressure distribution of the suction jig of the embodiment. (b) is a display diagram showing the result of performing the same simulation by changing the position of the vent hole.

Fig. 9 is a graph showing the results of measuring the relationship between the air flow rate and the suction force of the suction jig by experiments.

Fig. 10 is a graph showing the result of measuring the amount of deformation of the workpiece attracted by the suction jig by experiments.

Fig. 11 is a plan view of the suction jig of the comparative example.

Fig. 12 is a perspective view showing the state of the nozzle flow path of the suction jig of the comparative example.

Fig. 13(a) is a view showing a result of computer simulation of the flow of air of the suction jig of the comparative example. (b) is a display diagram showing the result of performing the same simulation by changing the position of the vent hole.

Fig. 14 (a) is a display diagram showing the results of computer simulation by the pressure distribution of the suction jig of the comparative example. (b) is a display diagram showing the result of performing the same simulation by changing the position of the vent hole.

Fig. 15 is a plan view showing a modification of the suction jig of the present invention.

Next, an embodiment of the present invention will be described with reference to the drawings. Fig. 1 is a transfer machine including a suction jig 10 according to an embodiment of the present invention. A perspective view of the arm (transfer device) 1.

The transfer robot 1 is configured as a so-called parallel mechanism robot. Specifically, the transfer robot arm includes a base portion 101, three arm portions 106, three electric motors 104, and one end plate 114.

A mounted surface P1 is formed on a lower surface portion of the base portion 101. On the other hand, the upper surface of the frame (not shown) for mounting the transfer robot 1 is used as a horizontal upward facing surface. In this configuration, the transfer robot 1 can be suspended in a state in which the mounted surface P1 of the base portion 101 is fixed to the mounting surface of the frame.

On the lower surface side of the base portion 101, three electric motors 104 are fixed at equal intervals in the circumferential direction around the central portion of the base portion 101 in plan view. Each of the electric motors 104 is provided with a speed reducer, and the base end portion of the arm portion 106 is fixed to the output shaft (that is, the output shaft of the speed reducer).

A joint portion 110 composed of a ball joint is provided in a portion of the middle portion of each arm portion 106, and the arm portion 106 is freely bendable at the joint portion 110. The front end of the three arm portions 106 is connected to one end plate 114. A motor 32 that is provided with the motor shaft facing downward is fixed to the base portion 101. The motor shaft of the motor 32 and the end plate 114 are connected by a revolving shaft 33 that transmits the rotation of the motor shaft to the end plate 114.

The parallel mechanism is configured as described above, and the transfer robot 1 can freely move the end plate 114 three-dimensionally within the range of the stroke of the arm portion 106 by appropriately controlling the three electric motors 104.

At the lower portion of the end plate 114, the suction jig of the present embodiment is mounted (White effort fixture) 10. Thereby, the transfer robot 1 of the present embodiment can move the suction jig 10 three-dimensionally within the range of the stroke of the arm portion 106. Hereinafter, the suction jig 10 is supplied with compressed air (compressed gas) so that the suction force is generated between the lower surface portion and the surface of the workpiece 90 (refer to FIG. 3) and the lower surface portion. A device that can attract and hold the workpiece in a non-contact manner.

The transfer robot 1 of the present embodiment supplies compressed air to the suction jig 10 to suck and hold the workpiece 90, and appropriately controls the electric motor 104 in this state, and causes the end plate 114 (and the suction jig 10 in a state in which the workpiece 90 is attracted). ) Move to the desired location. On the other hand, the transfer robot 1 rotates the suction jig 10 by appropriately driving the motor 32, and rotates the workpiece 90 sucked and held by the suction jig 10 in a substantially horizontal plane. The transfer robot 1 is configured to block the supply of the compressed air to the suction jig 10, thereby releasing the suction and holding of the workpiece 90, and placing the workpiece 90 at a desired position. As described above, in the transfer robot 1 of the present embodiment, the workpiece 90 can be sucked and held by the suction jig 10 to be moved to a desired position.

The workpiece 90 processed as the transfer robot 1 of the present embodiment is a workpiece that is predetermined to be formed into a thin flat plate shape and particularly rectangular. Examples of the workpiece 90 include a solar cell wafer, a unit of a fuel cell, an electrode of a secondary battery, a separator, a tantalum wafer, and the like, and are not limited thereto.

Next, the structure of the suction jig 10 of the present embodiment will be described in detail.

As shown in Fig. 2, the suction jig 10 is provided with a main body 11 which is formed in a flat shape as a whole. As shown in Fig. 3, the lower surface of the main body 11 is an opposing surface 31 that can directly face the workpiece 90. The opposing surface 31 is configured as a flat surface of a rectangular shape (orthogonal quadrangle) perpendicular to the thickness direction of the suction jig 10 . As shown in Fig. 2, a plurality of air ejection ports 41 for ejecting air and a plurality of exhaust holes 42 for discharging air are arranged in an array shape on the opposing surface 31 of the suction jig 10.

As shown in Fig. 3, the main body 11 of the suction jig 10 is formed so that a plurality of plate portions are stacked in the thickness direction. Specifically, the main body 11 is provided with a surface plate 25, a nozzle plate 26, a connecting plate 27, and a distribution plate 28 in this order from the side closer to the workpiece 90 (lower side). The lower surface portion of the surface plate 25 constitutes the above-described opposing surface 31.

The air ejection port 41 has a cylindrical space and is formed as a circular hole that penetrates the surface plate 25 and the nozzle plate 26 in the thickness direction. The air ejection port 41 is not formed in the connecting plate 27 and the distribution plate 28. That is, in the thickness direction of the suction jig 10, the one end portion (the upper end portion) of the air ejection port 41 is closed by the connecting plate 27. On the other hand, the other end portion (the lower end portion) of the air ejection port 41 is opened to the lower surface portion (opposing surface 31) of the surface plate 25.

As shown in FIG. 3, the nozzle plate 26 is formed with a nozzle flow path 44 that communicates with the air ejection port 41. The nozzle flow path 44 is specifically an elongated slit formed in the nozzle plate 26. As shown in FIGS. 4 and 5, the nozzle flow path 44 is formed such that its longitudinal direction is substantially coincident with the tangential direction of the air ejection port 41, and one end side of the longitudinal direction is connected to the space. A space inside the gas discharge port 41.

In the present embodiment, three nozzle flow paths 44 are formed with respect to one air ejection port 41. As shown in Fig. 5, the three nozzle flow paths 44 are formed so as to be 120 degrees out of phase with each other centering on the central axis of the air ejection port 41. Then, the three nozzle flow paths 44 are opened at equal intervals in the circumferential direction of the air ejection port 41 with respect to the inner peripheral wall of the air ejection port 41. The longitudinal direction of the nozzle flow path 44 is formed to be parallel with respect to the opposing surface 31. In the illustrated manner, in the cross-sectional view of Fig. 3, although the two nozzle flow paths 44 are opposed in the same cross section, this is a schematic diagram for explanation, and the nozzle flow path is not actually formed in this manner. 44.

As shown in FIGS. 3 to 5, the end portion of the nozzle flow path 44 on the side opposite to the air ejection port 41 is connected to the compressed air supply port 35. Thereby, the air ejection port 41 and the compressed air supply port 35 are communicated via the nozzle flow path 44. As shown in FIG. 3, the compressed air supply port 35 is a circular hole formed to penetrate the nozzle plate 26 and the connecting plate 27 in the thickness direction. The compressed air supply port 35 is formed to correspond to each nozzle flow path 44. That is, three compressed air supply ports 35 are formed in the nozzle plate 26 and the connecting plate 27 with respect to one air ejection port 41.

As shown in FIG. 3, the distribution plate 28 is formed with a distribution passage 43 that communicates with the three compressed air supply ports 35. The distribution passage 43 is connected to an appropriate compressed air source (for example, a compressor) via, for example, a joint 71 and a pipe 72, and a solenoid valve (not shown).

The exhaust hole 42 is formed as a circular hole and is formed to penetrate the plate portions 25, 26, 27, and 28 in the thickness direction. That is, the vent hole 42 is formed to be in The thickness direction penetrates the main body 11 of the suction jig 10 . Then, in the thickness direction of the suction jig 10, one end of the exhaust hole 42 is opened to the opposing surface 31, and the other end is opened to the upper surface of the main body 11 of the suction jig 10.

As shown in Fig. 5, in the present embodiment, each of the exhaust holes 42 is formed at equal intervals to form a vertex of the equilateral triangle. Further, each of the air ejection ports 41 is formed to be located at the center of gravity of the equilateral triangle formed by the three exhaust holes 42. Thereby, the three exhaust holes 42 in the vicinity of the respective air ejection ports 41 are arranged at equal intervals on the concentric circles centering the air ejection ports 41. However, the air ejection port 41 in the vicinity of the edge of the main body 11 does not have this limitation. This is because there is a portion where the vent hole 42 cannot be formed at the edge of the main body 11 (refer to Fig. 5).

As the material of the four plate portions 25 to 28, it is preferable to use a metal from the viewpoint of cost and the like. Specific examples of the material of the plate portions 25 to 28 include materials selected from stainless steel, aluminum alloy, or titanium alloy. The main body of the suction jig 10 is configured by diffusingly joining the four plate portions 25 to 28 in a state of being completely overlapped. In order to provide the suction jig 10 having a small dimensional accuracy and excellent precision, it is preferable to use the same material as the material of the four plate portions 25 to 28. This is because if different types of metals are diffusion bonded, deformation due to deflection or the like may occur due to residual strain after bonding. In the present embodiment, stainless steel is used as the material of the four plate portions 25 to 28.

The air ejection port 41, the nozzle flow path 44, the compressed air supply port 35, the distribution passage 43, and the exhaust hole 42 formed in the four plate portions 25 to 28 For example, it may be formed by etching, or may be formed by machining such as punching or drilling. Since the processing method such as etching can be used, it is easy to form the air ejection port 41, the nozzle flow path 44, and the like in an array shape in a small size. For example, in the present embodiment, the diameter of the air ejection port 41 is made to be about 3 mm.

Next, the operation of the suction jig 10 of the present embodiment configured as described above will be described with reference to FIG.

In order to suction and hold the workpiece 90 by the suction jig 10 of the above configuration, the solenoid valve connected to the compressed air source is turned on, and the supply of the compressed air to the distribution passage 43 is started. Thereby, compressed air is distributed from the distribution passage 43 to the three compressed air supply ports 35. The compressed air supplied to the compressed air supply port 35 flows through the nozzle flow path 44 that communicates with the compressed air supply port 35, and is discharged from the end of the nozzle flow path 44 toward the inside of the air ejection port 41.

As described above, each of the nozzle flow paths 44 is formed so that the longitudinal direction thereof is along the tangential direction of the air ejection port 41, so that the air ejected from the three nozzle flow paths 44 flows along the inner peripheral wall of the air ejection port 41 (refer to Figure 6). Thereby, the air is caused to flow back into the air ejection port 41 (for example, in Fig. 6, in the air ejection port 41, the air flows in the counterclockwise direction). However, in the suction jig 10 of the present embodiment, the air ejection port 41 has a very small diameter of 3 mm and is formed shallower than the diameter, so that the air inside the air ejection port 41 is not completely swirled. Then, the air ejected from the nozzle flow path 44 to the air ejection port 41 is slightly changed in the direction of the air ejection port 41 (Fig. 6). The air ejection port 41 is ejected.

As shown in Fig. 3(a), when the workpiece 90 is largely separated from the opposing surface 31, no attraction force is generated between the suction jig 10 and the workpiece 90.

However, as shown in Fig. 3(b), if the opposing surface 31 gradually approaches the workpiece 90, the negative pressure caused by the air ejected from the air ejection port 41 acts on the workpiece 90. The closer the distance between the opposing surface 31 and the workpiece 90 is, the larger the flow velocity of the air flowing between the opposing surface 31 and the workpiece 90 is, and is discharged upward through the exhaust hole 42. Thereby, the flow velocity increases when the air flow traveling along the inner wall surface of the air ejection port 41 toward the opposite surface 31, and the internal pressure of the air ejection port 41 decreases. The workpiece 90 is attracted toward the opposing surface 31 by the negative pressure generated thereby. On the other hand, between the workpiece 90 and the opposing surface 31, since there is an air layer formed by the ejected air from the air ejection port 41, the workpiece 90 is subjected to the repulsive force in the direction of being pulled away from the opposing surface 31. . Thus, the workpiece 90 is not completely attracted to the opposing face 31. The workpiece 90 is held in a non-contact manner with respect to the suction jig 10 by the balance of the attraction force and the repulsive force. As described above, the air ejection port 41 functions as a suction member that sucks and holds the workpiece 90 in a non-contact manner in the suction jig 10.

The air flowing between the opposing surface 31 and the workpiece 90 is discharged to the upper side of the suction jig 10 via the exhaust hole 42 (refer to FIG. 3(b)). Thereby, the air is not allowed to stay between the opposing surface 31 and the workpiece 90, so that the air can flow smoothly, and the attraction force can be efficiently operated.

As described above, the air is ejected from the nozzle flow path 44 to the air ejection port 41. The gas flows to swirl along the inner peripheral wall of the air ejection port 41, so that torque acts on the workpiece 90 at this time. Therefore, as shown in FIG. 5, the suction jig 10 of the present embodiment supplies compressed air to the nozzle flow path 44 of each air ejection port 41 in the opposite direction to the other air ejection port 41 in the vicinity. That is, the air ejection ports 41 adjacent to each other in the vicinity are formed such that the respective nozzle flow paths 44 are formed such that the direction in which the air flows inside is clockwise, counterclockwise, clockwise, and the like. Thereby, the torque generated by the swirling air is canceled, and the workpiece 90 sucked and held by the suction jig 10 can be prevented from rotating.

Further, if the number of the air ejection ports 41 whose flow direction is the clockwise direction is the same as the number of the air ejection ports 41 whose flow direction is the counterclockwise direction (the opposite direction), the rotation center of the workpiece 90 generated by each attraction member The sum of the rotational moments is zero, and the rotation of the workpiece 90 held by the suction jig 10 can be more effectively prevented from rotating.

As described above, in the suction jig 10 of the present embodiment, the surface of the workpiece 90 is sucked and held in a non-contact manner in the normal direction. However, only in the above configuration, in the direction parallel to the surface of the workpiece 90 (the direction parallel to the opposing surface 31), the workpiece 90 cannot be held. Then, when the suction jig 10 is attached to the transfer robot such as the parallel mechanism to transport the workpiece 90, a restriction member for restricting the movement of the workpiece 90 in the lateral direction is required. Therefore, a restriction member (not shown) is disposed in the peripheral portion of the suction jig 10 of the present embodiment. The restriction member (guide member) is described in paragraph 0106 of Japanese Patent Application No. 2011-94215.

For example, the edge of the suction jig 10 is fixed with: to surround the suction jig 10 is a plurality of guiding members arranged at intervals with each other. The guide member is disposed in each of the side portions of the suction jig 10 formed in a rectangular shape, and is disposed to face each other with the suction jig 10 interposed therebetween. The guide member is disposed perpendicular to the thickness direction of the suction jig 10 formed in a flat shape, and the lower end thereof protrudes downward from the lower surface portion (opposing surface 31) of the suction jig 10 . The guide member restricts the relative movement of the workpiece 90 in a direction parallel to the lower surface portion (opposing surface 31) of the suction jig 10 when the workpiece 90 held by the suction jig 10 is conveyed.

Next, the special effects obtained by the suction jig of the present embodiment will be described.

First, the inventors of the present invention obtained the flow of air from the air ejection port 41 by computer simulation in order to verify the effect of the suction jig 10 of the present embodiment. The result is shown in Figure 7. In this simulation, the equivalent hydraulic diameter ×3 of the nozzle flow path 44 is set to be equal to the equivalent hydraulic diameter ×2 of the nozzle flow path 44 of the suction jig 9 of the comparative example when the simulation of Fig. 13 is performed. Thereby, the simulation result (Fig. 13) of the suction jig 9 (Fig. 11) of the comparative example including the two nozzle flow paths 44, and the suction jig 10 of the present embodiment including the three nozzle flow paths 44 are provided. The simulation results (Fig. 7) can be compared under the same conditions. The suction jig 10 of the present embodiment in which the equivalent hydraulic diameter of the nozzle flow path 44 is set to be equivalent to the suction jig 9 of the comparative example is referred to as type A. The air ejection port 41 has a diameter of 3 mm.

As shown in Fig. 7(a), in the suction jig 10 of the present embodiment, the air ejected from the air ejection port 41 is ejected in three directions. That is It is said that the air can be dispersed and ejected from the air ejection port 41 as compared with the suction jig 9 of the comparative example in which the air is concentrated in both directions (the simulation result of FIG. 13). As a result, the air does not flow smoothly as in the suction jig 9 of the comparative example, and as shown in Fig. 7(a), the air from the air ejection port 41 can be smoothly flowed toward the exhaust hole 42. On the other hand, compared with the simulation result of the suction jig 9 of the comparative example shown in Fig. 13, in the simulation result of the suction jig of the present embodiment shown in Fig. 7(a), the loop of the air is flow-like. Significantly reduced, while air stagnation is less. In particular, in a state in which the workpiece is sucked and held (a state of ΔZ = 0.1), the loop-like flow almost disappears. In other words, it is understood that the suction jig 10 of the present embodiment can prevent the air from stagnating and can hold and hold the workpiece 90 in a smooth flow state.

Next, the inventors of the present invention obtained the pressure distribution around the air ejection port 41 by computer simulation in order to verify the uniformity of the suction force generated by the suction jig 10 of the present embodiment. The result is shown in Fig. 8. Fig. 8 is a view showing the pressure distribution when ΔZ = 0.1 mm in Fig. 7 (a state in which the workpiece 90 is sucked and held). As shown in Fig. 8 (a), in the suction jig 10 of the present embodiment, the distribution of the repulsive force around the air ejection port 41 is uniform, and the difference is compared with the suction jig 9 of the comparative example (the simulation result of Fig. 14). It is clear. In other words, the suction jig 10 of the present embodiment can disperse the air ejected from the air ejection port 41 in three directions. Therefore, compared with the suction jig 9 of the comparative example in which the air is concentrated in both directions, the suction jig 9 is compared with the suction jig 9 of the comparative example in which the air is concentrated in both directions. The attraction force generated inside the air ejection port and the vicinity of the edge portion can make the repulsive force uniform in the peripheral portion thereof. Suction of the present embodiment The lead jig 10 acts on the air ejection port in the same manner as the repulsive force which is distributed substantially evenly around the periphery of the workpiece 90, so that the effect of reducing the vibration and deformation of the workpiece 90 can be expected.

As shown in Fig. 6, the simulation result of the above-mentioned Fig. 7 (a) and Fig. 8 (a) is a case in which the air is ejected from the air ejection port 41 in three directions, and the exhaust holes 42 are formed. By arranging the exhaust hole 42 in the direction in which the air is ejected from the air ejection port 41, the air from the air ejection port 41 can flow most smoothly. However, it is not always possible to form the vent hole 42 in such an ideal arrangement. Therefore, the inventors of the present invention particularly arranged the vent hole 42 so that the air flowing out from the air ejection port 41 does not easily flow, and performs the same computer simulation as described above. The results are shown in Figures 7(b) and 8(b).

As shown in Fig. 7(b), when the position of the vent hole 42 is changed, when the flow of the air slightly changes, for example, ΔZ = 0.3, a loop-like flow is slightly generated. However, in the state in which the workpiece is sucked and held (the state of ΔZ = 0.1), the loop-like flow is almost eliminated, and it can be seen that the air does not stagnate and smoothly flows. As shown in Fig. 8(b), even when the position of the exhaust hole 42 is changed, the pressure distribution around the air ejection port 41 is uniform, and the result obtained is not that the exhaust hole 42 is disposed at an ideal position. The situation (Fig. 8 (a)) is inferior. By the suction jig 10 of the present embodiment, it is possible to make the air flow smoothly and to uniformize the pressure distribution regardless of the arrangement of the exhaust holes 42.

In the suction jig 9 of the comparative example shown in Figs. 11 and 12, since the air from the air ejection port 41 is concentrated in both directions, it is borrowed. The flow of air is greatly changed by the position of the vent hole 42. Therefore, in the suction jig 9 of the comparative example, the exhaust hole 42 cannot be freely arranged, and the degree of freedom in design is low. In the suction jig 10 of the present embodiment, the air from the air ejection port 41 is dispersed and discharged in three directions. Therefore, even if the position of the exhaust hole 42 is changed, the flow of air does not largely change. In other words, even if the position of the exhaust hole 42 is changed from the ideal position, the flow of the air does not largely change. Therefore, the air can be smoothly flowed in the same manner as the ideal state, and the repulsive force can be uniformly applied. Therefore, with the structure of the suction jig 10 of the present embodiment, the vent hole 42 can be freely disposed without paying attention to the flow of air, so that the degree of freedom in designing the suction jig 10 can be improved.

Then, the inventors of the present invention actually experimented with the suction jig 10 shown in Fig. 2 and performed an experiment comparing the magnitude of the suction force acting on the workpiece with the suction jig 9 (Fig. 11) of the comparative example. The result is shown in Figure 9. In Fig. 9, the horizontal axis represents the flow rate of the air supplied to the suction jig, and the vertical axis represents the attraction force of the entire suction jig to the workpiece. The curve shown as the two nozzles in Fig. 9 is an experimental result showing the suction jig 9 of the comparative example. The curve shown as the type A and the type B is an experimental result showing the suction jig 10 (the suction jig having three nozzle flow paths with respect to one air ejection port) of the present embodiment.

As described above, the suction jig of the type A is set such that the equivalent hydraulic diameter of the nozzle flow path 44 is equal to that of the suction jig 9 of the comparative example. On the other hand, the suction jig of the present embodiment shown as type B in Fig. 9 is set such that the total sectional area of the three nozzle flow paths 44 is equal to the total of the two nozzle flow paths 44 of the suction jig 9 of the comparative example. Sectional area. In the experiment, because of The suction jig of the present embodiment is set to have the same diameter and number of the air ejection ports 41 and the total opening area of the exhaust holes 42 in accordance with the conditions of the suction jig of the comparative example.

As shown in Fig. 9, the suction jig 10 (type A and type B) of the present embodiment has a higher suction force of the same air flow rate than the suction jig 9 of the comparative example. The suction jig 10 of the present embodiment allows air to smoothly flow from the air ejection port 41 to the exhaust hole 42, and as a result, the suction force can be efficiently generated with a small air flow rate. It has been confirmed that the suction jig 10 of the present embodiment having three nozzle flow paths 44 with respect to one air ejection port 41 is attracted to the suction jig 9 of the comparative example having two nozzle flow paths 44 for one air ejection port 41. The efficiency is even higher.

Next, the inventors of the present invention conducted an experiment of actually measuring the amount of deformation of the workpiece 90 by sucking and holding the thin-plate-shaped workpiece 90 on the suction jig. The workpiece used in this experiment was a crucible wafer having a square of 125 mm on the side and a corner portion of about 8 mm at four corners, and the length in the diagonal direction was about 165 mm, and the thickness was 110 μm. The results of the experiment are shown in Figure 10. The horizontal axis of Fig. 10 is a distance indicating a diagonal direction (a direction orthogonal to the thickness direction) of the workpiece 90 from the center position of the workpiece 90. The vertical axis indicates the relative position of each point of the workpiece 90 in the thickness direction of the workpiece 90. The larger the fluctuation of the vertical axis in Fig. 10, the larger the deformation of the workpiece 90 in the diagonal direction. In this experiment, the flow rate of the air supplied to each of the suction jigs was adjusted in advance so that the suction force of each of the suction jigs acting on the workpiece 90 was equal. As an attraction, it is considered that the acceleration generated when the transfer robot moves is related to the workpiece. The weight itself is set to a value sufficient to maintain the workpiece. Thereby, the suction jig 9 of the comparative example and the suction jig 10 of the present embodiment (type A and type B) can be compared under the same conditions.

As shown in Fig. 10, the workpiece 90 sucked and held by the suction jig 9 of the comparative example is deformed by 0.08 mm or more, and the amount of deformation of the workpiece 90 sucked and held by the suction jig 10 (type A and type B) of the present embodiment is relatively The maximum is also about 0.05mm. Further, it has been confirmed that the suction jig 10 of the present embodiment having the three nozzle flow paths 44 with respect to one air ejection port 41 can reduce the amount of deformation of the workpiece 90 more than the suction jig 9 of the comparative example.

As described above, the suction jig 10 of the present embodiment includes the flat body 11 , the opposing surface 31 , the plurality of air ejection ports 41 , and the plurality of exhaust holes 42 . Inside the main body 11, a flow path of compressed air is formed. The opposing surface 31 is a surface of the main body 11 facing the workpiece 90 side. The air ejection port 41 is opened to the opposing surface 31 in order to eject the compressed air supplied from the above-described flow path. The exhaust hole 42 is formed to open to the opposing surface 31 around the air ejection port 41, and penetrates the main body 11 in the thickness direction. Each of the air ejection ports 41 is formed in a cylindrical space, and includes a nozzle flow path 44 having three faces open to the inside of the space, and each of the nozzle flow paths 44 is ejected toward the direction along the inner wall of the cylindrical space. gas.

In this manner, by supplying the compressed air into the air ejection port 41 from the three nozzle flow paths 44, the flow of the compressed gas ejected from the ejection port 41 is dispersed in three directions. Due to the dispersion of the flow of compressed gas to the three parties Therefore, the influence of the position of the vent hole 42 on the flow of the compressed air becomes small, and as a result, the vent hole 42 can be freely disposed to increase the degree of design freedom. Further, since the pressure distribution is dispersed to uniformize the pressure distribution, vibration and deformation of the workpiece 90 can be prevented. By increasing the number of nozzle flow paths 44, the flow rate of the compressed gas per nozzle flow path 44 is reduced, so that the impact of the workpiece can be reduced by the air ejection.

In the suction jig 10 of the present embodiment, the openings of the three nozzle flow paths 44 are formed at equal intervals in the circumferential direction of the air ejection port 41.

By supplying the compressed gas into the air ejection port 41 from the nozzle flow paths 44 having the openings at equal intervals, the compressed gas discharged from the air ejection ports 41 can be uniformly dispersed in three directions.

In the suction jig 10 of the present embodiment, the longitudinal direction of the nozzle flow path 44 is formed to be parallel to the opposing surface 31.

Thereby, the compressed gas discharged from the air ejection port 41 can smoothly flow along the opposing surface 31.

In the suction jig 10 of the present embodiment, three exhaust holes 42 in the vicinity of the air ejection port 41 are formed on concentric circles around the air ejection port 41.

Thereby, the compressed gas discharged from the air ejection port 41 in three directions can be smoothly exhausted from the three exhaust holes 42.

In the suction jig 10 of the present embodiment, the exhaust holes 42 in the vicinity of the air ejection port 41 are formed at equal intervals on the concentric circles.

Thereby, the compressed gas can be uniformly dispersed and flowed to the exhaust hole 42, so that the pressure distribution around the air discharge port 41 can be more equalized.

In the suction jig of the present embodiment, the nozzle flow path 44 is formed in a flow direction of the compressed gas around the axis of the air ejection port 41 in the internal space of the arbitrary air ejection port 41, and at the air ejection port 41. The other air ejection ports 41 formed closest to each other are in opposite directions.

Thereby, the torque generated by the air swirling in the air ejection port 41 is eliminated, and the rotation of the workpiece 90 sucked and held by the suction jig 10 can be prevented.

The transfer robot 1 of the present embodiment includes the above-described suction jig 10 and a parallel mechanism that can move the suction jig 10 three-dimensionally within a predetermined range.

That is to say, the workpiece 90 sucked and held by the suction jig 10 can be freely moved three times by the parallel mechanism. According to the suction jig 10 of the present embodiment, the thin flat workpiece 90 can be prevented from being vibrated or deformed and held and held. Therefore, the robot arm 1 can be transferred, and the workpiece 90 can be prevented from being deformed or damaged. Move to any location.

Although the preferred embodiment of the present invention has been described above, the above configuration may be changed to, for example, the following.

The suction jig 10 is mounted on the parallel mechanism type transfer robot 1 as described above, and is not limited thereto, and can be applied to, for example, a horizontal articulated arm type transfer robot.

In the above embodiment, the shape of the opposing surface 31 of the suction jig 10 is rectangular, and is not limited thereto, and may be formed into an appropriate shape. The shape of the opposing surface 31 of the suction jig 10 is suitable for being able to attract as long as it is formed in substantially the same shape as the shape of the workpiece 90 to be processed, and is slightly larger than the workpiece. The flow does not waste and evenly act on the workpiece 90.

The number and arrangement of the air ejection ports 41 formed in the opposing surface 31 can be appropriately changed in accordance with the weight and size of the workpiece 90.

In the above embodiment, the compressed gas supplied to the discharge port is air, and of course, other gases such as nitrogen may be supplied.

In the above embodiment, three exhaust holes 42 are provided in the vicinity of one air ejection port 41, and the present invention is not limited thereto. For example, as shown in Fig. 15, four exhaust holes may be formed around one air ejection port 41. 42. Other arrangements and numbers of the vent holes 42 can be freely changed. The suction jig 10 of the present invention has a special effect of allowing air to flow smoothly even if the vent hole 42 is disposed. Further, since the suction jig 10 of the present invention discharges air from three air ejection ports 41 in three directions, the structure of the above-described embodiment in which three exhaust holes 42 are disposed in the vicinity of one air ejection port 41 allows the air to be the smoothest. The ground flows, and the flow of the air is not easily disturbed, so it is particularly suitable.

The structure (the compressed air supply port 35, the distribution path 43, and the like) for supplying air to each of the nozzle flow paths 44 is not limited to the structure of the above-described embodiment, and can be appropriately changed. The internal structure of one air ejection port 41 is required to inject air from three directions, and the detailed structure thereof is not particularly limited.

10‧‧‧Attraction fixture

11‧‧‧ Subject

31‧‧‧relative

35‧‧‧Compressed air supply port

41‧‧‧Air outlet (spray outlet)

42‧‧‧ venting holes

44‧‧‧Nozzle flow path

Claims (7)

A suction jig that attracts a thin flat workpiece and holds it in a non-contact state; the suction jig includes: a flat body, a facing surface, a plurality of discharge ports, and a plurality of rows a flat-shaped body having a flow path for forming a compressed gas therein; the opposing surface being a surface facing the workpiece on the workpiece side; and the plurality of discharge ports for the passage from the flow path The supplied compressed gas is ejected and opened to the opposite surface; the plurality of exhaust holes are formed to open to the opposite surface around the discharge port, and penetrate the main body in the thickness direction; and the discharge ports are formed as The cylindrical space is provided with a nozzle flow path having three faces open to the inside of the space, and each nozzle flow path discharges compressed gas toward a direction along the inner wall of the cylindrical space. In the suction jig according to the first aspect of the invention, the openings of the three nozzle flow paths are formed at equal intervals in the circumferential direction of the discharge port. The suction jig according to claim 1 or 2, wherein the longitudinal direction of the nozzle flow path is formed to be parallel to the opposing surface. The suction jig according to claim 1 or 2, wherein at least three of the vent holes in the vicinity of the discharge port are formed on a concentric circle centered on the discharge port. Such as the suction jig of claim 4, wherein the above ejection The nearest vent holes of the mouth are formed at equal intervals on the concentric circles described above. The suction jig according to claim 1 or 2, wherein the nozzle flow path is formed in a flow direction of compressed gas around an axis of the discharge port in an internal space of an arbitrary discharge port, and at a maximum of the discharge port The other spouts formed nearby are in opposite directions. A transfer device comprising: the suction jig according to any one of claims 1 to 6; and a parallel mechanism capable of moving the suction jig three times within a predetermined range.