Hand of an industrial robot and industrial robot

Abstract

The hand of the industrial robot includes a loading section (33) for loading a flat object (3) to be transported. The loading section (33) has a concave curved support surface (33b) that contacts the lower end of the end face of the object (3) and supports the lower end of the end face of the object (3) from below. The support surface (33b) is inclined upward toward the outer periphery of the object (3). The cross section of the loading section (33) defined by the direction from the center of the object (3) toward the outer periphery of the object (3) and the vertical direction is defined as the first cross section. The overall cross section shape of the support surface (33b) in the first cross section is curved.

Description

Technical Field

[0001] This invention relates to the hand of an industrial robot. This invention also relates to industrial robots. Background Technology

[0002] Previously, a robot for handling semiconductor wafers was known (see, for example, Patent Document 1). The robot described in Patent Document 1 (an indexing robot) includes a hand that holds the semiconductor wafer. Four wafer support members are provided on the upper surface of the hand, supporting the peripheral portion of the semiconductor wafer from below and limiting the relative horizontal movement of the semiconductor wafer on the hand by opposing the peripheral end face of the semiconductor wafer. The wafer support members include: a wafer contact portion that contacts the peripheral portion of the semiconductor wafer to support the semiconductor wafer from below; and a conical surface that rises obliquely upwards from the wafer contact portion.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2002-313874 Summary of the Invention

[0006] In the robot described in Patent Document 1, the semiconductor wafer can be moved by the hand until the peripheral end face of the semiconductor wafer contacts the conical surface of the wafer support member. Therefore, for such a robot, for example, if the acceleration / deceleration of the hand increases when handling the semiconductor wafer, the position of the semiconductor wafer on the hand may shift, making it difficult to handle the semiconductor wafer accurately.

[0007] Therefore, the technical problem of the present invention is to provide a hand for an industrial robot, which is used to transport objects and can suppress positional deviation of the objects loaded on the hand. Another technical problem of the present invention is to provide an industrial robot including such a hand.

[0008] To solve the above-mentioned technical problems, one aspect of the present invention provides an industrial robot hand for transporting an object, comprising a loading portion for loading a flat object, the loading portion having a concave curved support surface, the support surface contacting and supporting the lower end of the end face of the object from below, the support surface being inclined upwards towards the outer periphery of the object, and a first cross-section defined by the direction from the center of the object towards the outer periphery and the vertical direction, wherein the overall cross-sectional shape of the support surface in the first cross-section is curved.

[0009] In the hand of the industrial robot of this method, the loading section for loading a flat object has a concave curved support surface. This support surface contacts the lower end of the end face of the object and supports the lower end of the end face of the object from below. The support surface is inclined upwards as it moves toward the outer periphery of the object. Furthermore, in this method, in the first cross-section of the loading section defined by the direction from the center of the object toward the outer periphery and the vertical direction, the overall cross-sectional shape of the support surface is curved. Therefore, in this method, the positional deviation of the object loaded on the hand can be suppressed by using a support surface with a curved cross-sectional shape.

[0010] Furthermore, in this method, the support surface is formed as described above. Therefore, as the deviation between the transported object loaded on the loading unit and its normal loading position increases, the force exerted by the support surface on the transported object in the direction that brings it closer to its normal loading position increases. Thus, in this method, the transported object can be loaded onto the loading unit at a position closer to its normal loading position, thereby suppressing the deviation between the transported object loaded on the hand and its normal loading position.

[0011] This type of hand can be applied, for example, to industrial robots comprising an arm for connecting the hand and a main body for connecting the arm. This industrial robot can suppress positional deviations of the object being transported on the hand. Furthermore, this industrial robot can suppress deviations of the object being transported on the hand from its normal loading position.

[0012] This method of operation can be applied, for example, to industrial robots comprising an arm for hand connection and a main body for arm connection. The industrial robot transports objects relative to a storage section. The storage section can store multiple objects at regular intervals in the vertical direction. The loading section has a planar loading surface perpendicular to the vertical direction and connected to the lower end of a support surface. The ends of the objects loaded onto the loading section have rounded chamfers in the vertical direction. The intersection of the extension line of the end face of the object loaded onto the loading section and the extension line of the lower surface of the object in the first cross-section is defined as the first intersection point. The maximum radial deviation of the hand in the storage section when the industrial robot transports objects relative to the storage section is defined as the first deviation. The maximum permissible radial deviation of the object being transported by the industrial robot to the storage section is defined as the second deviation. The sum of the first and second deviations is defined as the third deviation. A point in the first cross-section, located radially outward from the first intersection point and a distance from the third deviation and upward from the first intersection point at a predetermined distance based on the vertical thickness of the loading section, is defined as the first reference point. The intersection of the loading surface in the first cross-section and an imaginary straight line passing through the first intersection point and inclined at a predetermined angle relative to the loading surface is defined as the second reference point. The radius of curvature of the entire cross-section of the support surface in the first cross-section is the radius of the imaginary circle passing through the first intersection point, the first reference point, and the second reference point in the first cross-section. This industrial robot can suppress positional deviation of the object being transported on its hand. Furthermore, this industrial robot can suppress deviation of the object being transported on its hand from its normal loading position.

[0013] As described above, according to one aspect of the present invention, the hand of an industrial robot that transports objects can suppress positional deviation of the objects loaded on the hand. Attached Figure Description

[0014] Figure 1 This is a top view of the industrial robot according to an embodiment of the present invention.

[0015] Figure 2 yes Figure 1 A rear view of a portion of the industrial robot shown.

[0016] Figure 3 yes Figure 1 A side view of a portion of the industrial robot shown.

[0017] Figure 4 It is used to explain storage Figure 1 A diagram showing the structure of the housing portion of the semiconductor wafer shown in Figure 1.

[0018] Figure 5 It is used for explanation Figure 1 A cross-sectional view of the structure of part E in the diagram.

[0019] Figure 6 It is used for explanation Figure 1 A cross-sectional view of the structure of part F in the diagram.

[0020] Figure 7 It is used for explanation Figure 5 The diagram shows the method for setting the radius of curvature of the support surface. Detailed Implementation

[0021] Embodiments of the present invention will now be described with reference to the accompanying drawings.

[0022] (Overall structure of industrial robot)

[0023] Figure 1 This is a top view of the industrial robot 2 according to an embodiment of the present invention. Figure 2 yes Figure 1 Rear view of a portion of the industrial robot 2 shown. Figure 3 yes Figure 1 A side view of a portion of the industrial robot 2 shown. Figure 4 It is used to explain storage Figure 1 A diagram showing the structure of the housing part 4 of the semiconductor wafer 3.

[0024] The industrial robot 2 (hereinafter referred to as "robot 2") of this embodiment is a horizontal multi-joint robot used to transport semiconductor wafers 3 (hereinafter referred to as "wafers 3"), which are the objects to be transported. The wafer 3 is formed in the shape of a flat plate. Specifically, the wafer 3 is in the shape of a thin disk. For example, the diameter of the wafer 3 is 300 mm. For example, the thickness of the wafer 3 is 0.775 mm. For example, the robot 2 transports the wafers 3 relative to the storage section 4, which can store multiple wafers 3 at certain intervals in the vertical direction. For example, the storage section is a FOUP (front-opening unified container) that can store 25 wafers 3 at certain intervals in the vertical direction.

[0025] Robot 2 includes: two hands 5 and 6 for mounting the chip 3; an arm 7 rotatably connected to the hand 5 at its front end; an arm 8 rotatably connected to the hand 6 at its front end; a main body 9 for rotatably connecting the base ends of the arm 7 and the arm 8; and a housing 10 for housing the main body 9. In other words, robot 2 is a dual-arm robot. Arms 7 and 8 are multi-jointed arms that extend and retract in the horizontal direction.

[0026] Arm 7 includes: an arm portion 13 whose base end is rotatably connected to the main body portion 9; and an arm portion 14 whose base end is rotatably connected to the front end of the arm portion 13. In this embodiment, arm 7 is composed of arm portion 13 and arm portion 14. Arm portion 14 is disposed on the upper side of arm portion 13. The base end of hand 5 is rotatably connected to the front end of arm portion 14. The base end of hand 5 is disposed on the upper side of the front end of arm portion 14.

[0027] The arm 8 includes: an arm portion 15 whose base end is rotatably connected to the main body portion 9; and an arm portion 16 whose base end is rotatably connected to the front end of the arm portion 15. In this embodiment, the arm 8 is composed of the arm portion 15 and the arm portion 16. The arm portion 16 is disposed on the upper side of the arm portion 15. The base end of the hand 6 is rotatably connected to the front end of the arm portion 16. The base end of the hand 6 is disposed on the upper side of the front end of the arm portion 16.

[0028] Arms 7 and 8 can extend and retract horizontally between a position where the front ends of hands 5 and 6 are away from the main body 9 when arms 7 and 8 are extended and the front ends of hands 5 and 6 are close to the main body 9 when arms 7 and 8 are retracted. Hand 5, which transports wafer 3 to the storage section 4, moves linearly in a fixed direction. That is, when hand 5 transports wafer 3, arm 7 extends and retracts relative to the main body 9, causing hand 5 to move linearly in a fixed direction. Similarly, hand 6, which transports wafer 3 to the storage section 4, moves linearly in a fixed direction. That is, when hand 6 transports wafer 3, arm 8 extends and retracts relative to the main body 9, causing hand 6 to move linearly in a fixed direction.

[0029] The base ends of arm 13 and arm 15 overlap in the vertical direction. In this embodiment, the base end of arm 13 is positioned below the base end of arm 15. Furthermore, the base ends of arm 13 and arm 15 are positioned above the main body 9. When arms 7 and 8 are retracted to a predetermined reference position, the front ends of arm 14 and arm 16 overlap in the vertical direction. That is, when arms 7 and 8 are retracted to a predetermined reference position, hands 5 and 6 overlap in the vertical direction. In this embodiment, the front end of arm 14 is positioned above the front end of arm 16, and hand 5 is positioned above hand 6. When arms 7 and 8 are retracted to the reference position, viewed from above, arms 7 and 8 are symmetrically bent and symmetrically arranged.

[0030] In this embodiment, arms 7 and 8 are parallel linkage arms having two parallel linkage mechanisms 22. Arm 13 is composed of two (a pair) parallel arms 23 and 24, and arm 14 is composed of two parallel arms 25 and 26. Arm 15 is composed of two parallel arms 27 and 28, and arm 16 is composed of two parallel arms 29 and 30. Parallel arms 23 to 30 are formed, for example, of aluminum alloy. Parallel arms 23 and 24 are arranged at the same height, and parallel arms 25 and 26 are arranged at the same height. Parallel arms 27 and 28 are arranged at the same height, and parallel arms 29 and 30 are arranged at the same height.

[0031] The base ends of parallel arms 23, 24, 27, and 28 are rotatably connected to the main body 9. Hand 5 is rotatably connected to the front ends of parallel arms 25 and 26. Hand 6 is rotatably connected to the front ends of parallel arms 29 and 30. The base end of parallel arm 25 is rotatably connected to the front end of parallel arm 23, and the base end of parallel arm 26 is rotatably connected to the front end of parallel arm 24. The base end of parallel arm 29 is rotatably connected to the front end of parallel arm 27, and the base end of parallel arm 30 is rotatably connected to the front end of parallel arm 28.

[0032] In the horizontal direction, the distances between the rotation center of parallel arm 23 relative to the main body 9 and the rotation center of parallel arm 25 relative to parallel arm 23, the distances between the rotation center of parallel arm 24 relative to the main body 9 and the rotation center of parallel arm 26 relative to parallel arm 24, the distances between the rotation center of parallel arm 25 relative to parallel arm 23 and the rotation center of hand 5 relative to parallel arm 25, and the distances between the rotation center of parallel arm 26 relative to parallel arm 24 and the rotation center of hand 5 relative to parallel arm 26 are all equal.

[0033] Furthermore, in the horizontal direction, these distances are equal to the distance between the rotation center of parallel arm 27 relative to the main body 9 and the rotation center of parallel arm 29 relative to parallel arm 27, the distance between the rotation center of parallel arm 28 relative to the main body 9 and the rotation center of parallel arm 30 relative to parallel arm 28, the distance between the rotation center of parallel arm 29 relative to parallel arm 27 and the rotation center of hand 6 relative to parallel arm 29, and the distance between the rotation center of parallel arm 30 relative to parallel arm 28 and the rotation center of hand 6 relative to parallel arm 30.

[0034] Robot 2 also includes: a first arm drive mechanism for rotating arms 13 and 14 to extend and retract arm 7; a second arm drive mechanism for rotating arms 15 and 16 to extend and retract arm 8; a lifting mechanism for raising and lowering arms 7 and 8, main body 9, the first arm drive mechanism, and the second arm drive mechanism relative to housing 10; and a rotation mechanism for rotating arms 7 and 8, main body 9, the first arm drive mechanism, the second arm drive mechanism, and the lifting mechanism relative to housing 10 with the up-down direction as the rotation axis. The first arm drive mechanism, the second arm drive mechanism, the lifting mechanism, and the rotation mechanism are housed within housing 10.

[0035] (The structure of the hand)

[0036] Figure 5 It is used for explanation Figure 1 A cross-sectional view of the structure of part E in the diagram. Figure 6 It is used for explanation Figure 1 A cross-sectional view of the structure of part F in the diagram. Figure 7It is used for explanation Figure 5 The diagram shows the method for setting the radius of curvature R of the support surface 33b.

[0037] Hands 5 and 6 include: a loading portion 33 for loading the wafer 3; and a hand base 34 for fixing the loading portion 33. The hand base 34 is rotatably connected to the front end of the arms 14 and 16. The base end of the loading portion 33 is fixed to the hand base 34. The loading portion 33 is formed as a flat plate with its thickness direction in the vertical direction. The loading portion 33 is, for example, made of ceramic. When viewed from the vertical direction, the loading portion 33 has a Y-shaped shape. The front end side of the loading portion 33 is forked.

[0038] The wafer 3 is loaded into the loading section 33, with the thickness direction of the wafer 3 aligned with the vertical direction. For example... Figure 5 and Figure 6 As shown, the wafer 3 mounted on the loading section 33 has rounded chamfers (rounded corners) at both ends of its end face in the vertical direction. When the diameter of the wafer 3 is 300mm, the radius of curvature of the chamfer at the end face of the wafer 3 is about 0.2mm.

[0039] The loading portion 33 has a concave curved support surface 33b, which contacts the lower end of the end face of the wafer 3 and supports the end face of the wafer 3 from below. The support surface 33b is inclined upwards toward the outer periphery of the wafer 3 (i.e., toward the radially outer side of the wafer 3). The support surface 33b is formed at four locations. Specifically, the support surface 33b is formed at two locations in the middle between the front end and the base end of the loading portion 33, and at two locations at the front end of the loading portion 33. The portion of the loading portion 33 in which the support surface 33b is formed is called the support surface forming portion 33c. The loading portion 33 also has a planar loading surface 33d, which is perpendicular to the vertical direction and connected to the lower end of the support surface 33b.

[0040] If we define the cross-section of the loading portion 33 by the direction from the center of the wafer 3 toward the outer periphery of the wafer 3 and the vertical direction (i.e., the cross-section of the loading portion 33 defined by the radial and vertical directions of the wafer 3), Figure 5 and Figure 6 If the cross-section of the loading part 33 shown is designated as the first cross-section, then the overall cross-sectional shape of the support surface 33b in the first cross-section is curved. Specifically, the overall cross-sectional shape of the support surface 33b in the first cross-section is an arc shape. The radius of curvature R of the support surface 33b in the first cross-section is set as follows.

[0041] In the following description, such as Figure 7As shown, the intersection of the extension line of the end face of the wafer 3 mounted on the loading section 33 and the extension line of the lower surface of the wafer 3 in the first cross section is defined as the first intersection point C1. In the following description, the maximum deviation of the hands 5 and 6 in the radial direction of the wafer 3 when the robot 2 moves the wafer 3 relative to the storage section 4 (the maximum deviation of the repeatedly moving hands 5 and 6) is defined as the first deviation; the maximum permissible deviation of the wafer 3 in the radial direction when the wafer 3 is moved from the robot 2 to the storage section 4 is defined as the second deviation; and the sum of the first deviation and the second deviation is defined as the third deviation X.

[0042] Furthermore, in the following description, the point in the first cross section that is radially outward from the first intersection point C1 and away from the wafer 3 by a third deviation amount X and a predetermined first distance Y from the first intersection point C1 upwards based on the vertical thickness of the loading portion 33 is designated as the first reference point C2, and the point in the first cross section that is the intersection of the loading surface 33d and the imaginary straight line VL that passes through the first intersection point C1 and is inclined at a predetermined angle θ1 relative to the loading surface 33d is designated as the second reference point C3.

[0043] The first deviation is set based on the rigidity of the hands 5, 6, etc. The second deviation is set based on the specifications of the storage section 4, etc. The vertical thickness of the loading section 33 is set based on the gap between the lower surfaces of the upper and lower wafers 3 of the two wafers 3 arranged adjacent to each other in the vertical direction in the storage section 4, as well as the rigidity of the hands 5, 6, etc. The first distance Y is set based on the maximum vertical deviation of the hands 5, 6 in the storage section 4 (the maximum deviation of the repeatedly moving hands 5, 6) when the robot 2 moves the wafers 3 relative to the storage section 4, and the vertical thickness of the loading section 33. The angle θ1 is set empirically. In this embodiment, the angle θ1 is 15°.

[0044] The upper surface of the loading part 33, excluding the support surface 33b and the loading surface 33d, is positioned at a first distance Y above the first intersection point C1. This upper surface of the loading part 33 is a plane perpendicular to the vertical direction. The radius of curvature R of the entire cross-section of the support surface 33b in the first section is the radius of the imaginary circle VC passing through the first intersection point C1, the first reference point C2, and the second reference point C3 in the first section.

[0045] For example, when the diameter of wafer 3 is 300 mm, the radius of curvature R is 3 to 4 mm. Specifically, when the diameter of wafer 3 is 300 mm, the radius of curvature R is 3.234 mm. In this embodiment, the third deviation X is 1 mm, and the first distance Y is 1 mm. In the first cross-section, the angle θ2 of the line connecting the first intersection point C1 and the first reference point C2 with respect to the horizontal direction is 45°. The vertical distance between the lower surface of wafer 3, which is mounted in the normal mounting position of the mounting part 33, and the mounting surface 33d is 0.5 mm.

[0046] (Main effects of this implementation method)

[0047] As described above, in this embodiment, the loading portion 33 for loading the wafer 3 has a concave curved support surface 33b. This support surface 33b contacts the lower end of the wafer 3's end face and supports the lower end of the wafer 3's end face from below. The support surface 33b is inclined upwards as it moves toward the outer periphery of the wafer 3. In this embodiment, the entire cross-sectional shape of the support surface 33b in the first cross-section of the loading portion 33 is arc-shaped. Therefore, in this embodiment, the positional deviation of the wafer 3 loaded on the hands 5 and 6 can be suppressed by using the arc-shaped support surface 33b.

[0048] Furthermore, in this embodiment, the support surface 33b is formed as described above. Therefore, when the deviation of the wafer 3 mounted on the loading portion 33 from its normal loading position increases, the force applied by the support surface 33b to the wafer 3 in the direction that brings the wafer 3 closer to its normal loading position increases. Therefore, in this embodiment, the wafer 3 can be mounted on the loading portion 33 at a position closer to its normal loading position, and as a result, deviation of the wafer 3 mounted on the hands 5 and 6 from its normal loading position can be suppressed.

[0049] (Other implementation methods)

[0050] The above-described embodiments are examples of preferred embodiments of the present invention, but are not limited thereto. Various modifications can be made without departing from the spirit of the present invention.

[0051] In the above embodiment, the overall cross-sectional shape of the support surface 33b in the first section can be a curved surface shape other than an arc. In the above embodiment, arms 7 and 8 may not be parallel link arms. That is, arms 13 to 16 may each be composed of a single arm. Furthermore, in the above embodiment, hands 5 and 6 are arranged in a state of offset in the vertical direction, but it is also possible that the base ends of arms 7 and 8 are arranged in the same position in the vertical direction in a manner that is adjacent in the horizontal direction, and hands 5 and 6 are arranged in the same position in the vertical direction.

[0052] In the above embodiments, robot 2 may not include arms 7 and 8, but rather a slender, approximately cuboid arm that holds hands 5 and 6, such as the arm of an industrial robot disclosed in Japanese Patent Application Publication No. 2019-25585, thereby enabling hands 5 and 6 to reciprocate linearly in the horizontal direction. That is, robot 2 may be a so-called linear robot, in which hands 5 and 6 are attached to the arm so that they can slide in the horizontal direction.

[0053] In the above embodiments, the robot 2 may include only one hand and one arm. For example, the robot 2 may include only one hand 5 and one arm 7. Furthermore, when the robot 2 includes only one hand and one arm, the arm 7 may be composed of three or more arm segments. For example, the arm 7 may be a three-bar linkage composed of three arm segments. In the above embodiments, the object to be transported by the robot 2 may be an object other than the wafer 3. In this case, the object to be transported may, for example, be formed into a rectangular flat plate.

[0054] (The composition of this technology)

[0055] In this technology, for example, the object to be transported is formed in a disk shape, and the first cross-section is defined by the radial and vertical directions of the object to be transported. The cross-sectional shape of the support surface in the first cross-section is an arc shape. Furthermore, in this technology, for example, the radius of curvature of the cross-section of the support surface in the first cross-section is 3 to 4 mm.

[0056] Symbol Explanation

[0057] 2. Robots (Industrial Robots)

[0058] 3. Chip (semiconductor chip, object to be transported)

[0059] 4. Storage Department

[0060] 5, 6 hands

[0061] 7th and 8th arms

[0062] 9. Main body

[0063] 33 Loading Section

[0064] 33b Support surface

[0065] 33d loading surface

[0066] C1 First intersection point

[0067] C2 First reference point

[0068] C3 Second Reference Point

[0069] R (radius of curvature)

[0070] VC Imaginary Circle

[0071] VL Imaginary Straight Line

[0072] X Third Deviation

[0073] Y is the first distance.

Claims

1. A hand of an industrial robot, the industrial robot being used to move objects, characterized in that, Includes a loading section for loading the flat, transportable object. The loading section has a concave curved support surface that contacts the lower end of the end face of the object being transported and supports the lower end of the end face of the object being transported from below. The support surface is inclined upwards as it moves toward the outer periphery of the object being transported. The first section is defined by the cross-section of the loading part, which is defined by the direction from the center of the object being transported toward the outer periphery of the object being transported and the vertical direction. The cross-sectional shape of the support surface in the first section is curved.

2. The hand of the industrial robot according to claim 1, characterized in that, The object being transported is formed in the shape of a disc. The first cross-section is defined by the radial and vertical directions of the object being transported. The overall cross-sectional shape of the supporting surface in the first section is an arc shape.

3. An industrial robot, characterized in that, include: The hand as described in claim 1 or 2; The arm connected to the hand; as well as The main body part connected to the arm.

4. An industrial robot, characterized in that, include: The hand as described in claim 2; The arm connected to the hand; as well as The main body connected to the arm, The industrial robot moves the transported objects relative to the storage unit, which can store multiple transported objects at certain intervals in the vertical direction. The loading part has a planar loading surface that is perpendicular to the vertical direction and is connected to the lower end of the support surface. The vertical ends of the object being transported, mounted on the loading unit, are chamfered in an arc shape. The first intersection point is defined as the point where the extension line of the end face of the object to be transported loaded onto the loading part and the extension line of the lower surface of the object to be transported are extended in the first cross section. The maximum radial deviation of the hand of the industrial robot relative to the storage part when transporting the object to be transported is defined as the first deviation. The maximum permissible radial deviation of the object to be transported by the industrial robot to the storage part is defined as the second deviation. The sum of the first deviation and the second deviation is defined as the third deviation. The first reference point is defined as the point in the first cross section that is radially outward from the first intersection point, away from the third deviation, and upward from the first intersection point, away from the first distance based on the vertical thickness of the loading part. The second reference point is defined as the point where the loading surface in the first cross section intersects with an imaginary straight line passing through the first intersection point and inclined at a predetermined angle relative to the loading surface. The radius of curvature of the entire cross section of the supporting surface in the first cross section is the radius of the imaginary circle passing through the first intersection point, the first reference point, and the second reference point in the first cross section.

5. The industrial robot according to claim 4, characterized in that, The radius of curvature of the entire cross section of the supporting surface in the first section is 3 to 4 mm.

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