JP2005279812A - Transfer apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a transfer apparatus, shortening the operation cycle time to improve productivity, and constructed at a low cost and in a compact manner. <P>SOLUTION: A transfer arm 2 having a holding part 3 for an object at the tip is fixed to one end of an operating shaft 5, the operating shaft 5 is inserted in a hollow part 7 of a direct drive motor 6 having the hollow part 7, a rotary board 8 fixed to one end of a rotating part of the direct drive motor 6 and the operating shaft 5 are coupled to each other through a ball spline 9 to freely move relatively in the axial direction, a nut member 11 disabled from freely rotating is connected to the other end of the operating shaft 5 not to move in the direction of the shaft center and to freely rotate mutually, one end of a screw shaft 12, the middle part of which is engaged with the nut member 11, is inserted in a hollow part 13 formed at the other end of the operating shaft 5, and the other end thereof is coupled to an AC servo motor 15. In this configuration, the transfer arm 2 is caused to perform rotary motion by the direct drive motor 6 and perform axial movement by the AC servo motor 15. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a transfer device, and in particular, holds a target object with a rotatable transfer arm having a target holding portion at a tip, and moves the target by moving and rotating the transfer arm in the rotation axis direction. The present invention relates to a transfer device for transfer.

  2. Description of the Related Art Conventionally, for example, as a substrate transfer device, various devices are known in which a transfer arm is configured to transfer a substrate to a predetermined position by rotating and moving up and down and expanding and contracting with a drive unit. (For example, refer to Patent Document 1).

  In such a transfer apparatus, a conventional configuration example in which the transfer arm performs rotation and vertical movement will be described with reference to FIG. A base end or center support boss 43 of a transfer arm 41 having an object holding portion 42 at the distal end is fixed to an upper end of an operation shaft 44 that can rotate and move up and down. The operating shaft 44 is disposed to pass through the hollow portion 46 of the direct drive motor 45 and can be driven to rotate via a ball spline sleeve 48 fixed to a rotating portion (rotor portion) 45a of the direct drive motor 45. It is engaged so as to be movable in the axial direction. A cylinder device 52 is connected to the lower end of the operating shaft 44 via a connecting bearing portion 51 that allows relative rotation and transmits axial force. Then, the transfer arm 41 is rotated by the direct drive motor 45 through the ball spline sleeve 48 and the operation shaft 44, and the transfer arm 41 is moved up and down by the cylinder device 52 through the connection bearing portion 51 and the operation shaft 44. By doing so, the object held by the holding portion 42 at the tip of the transfer arm 41 is transferred.

Another conventional configuration example will be described with reference to FIG. An operation shaft 63 having a transfer arm 61 having a holding portion 62 at the tip end fixed to the upper end portion is disposed through the hollow portion 65 of the first direct drive motor 64. A spline sleeve 66 is fixed to the rotating portion (rotor portion) 64a of the first direct drive motor 64 so as to be engaged with the operating shaft 63 so as to be rotationally driven and movable in the axial direction. The lower end of the operating shaft 63 is connected to the upper end of the screw shaft 68 via a connecting bearing portion 67 that allows relative rotation and transmits axial force. A nut member 70 screwed into a screw shaft 68 that is guided so as to be unrotatable and movable up and down (not shown) is fixed to a rotating portion (rotor portion) 71 a of a second direct drive motor 71 having a hollow portion 72. Yes. Then, the transfer arm 61 is rotated by the first direct drive motor 64 via the spline sleeve 66 and the operation shaft 63, and the nut member 70 is rotated by the second direct drive motor 71, thereby operating the screw shaft 68 and the operation. By moving the transfer arm 61 up and down via the shaft 63, the object held by the holding portion 62 at the tip of the transfer arm 61 is transferred.
JP 2001-196437 A

  However, in the configuration shown in FIG. 5, the rotational movement of the transfer arm 41 and the operation shaft 44 is performed by the direct drive motor 45, and the vertical movement is performed by the cylinder device 52, which is difficult to perform delicate operation control. In order to ensure a highly reliable transfer operation, it is necessary to perform the rotation operation after the vertical movement by the cylinder device 52 is completely stopped, for example, about 4 sec for one reciprocal transfer operation. There is a problem that the operation tact time is long and it becomes a hindrance to productivity improvement.

  Further, since the vertical movement space of the transfer arm 41, the ball spline sleeve 48, the direct drive motor 45, the coupling bearing portion 51, the expansion / contraction space of the cylinder rod, and the cylinder device 52 are arranged in series in the vertical direction, There is a problem that the size increases and a large installation space is required in the vertical direction.

  On the other hand, in the configuration shown in FIG. 6, the first direct drive motor 64 rotates the operating shaft 63, the second direct drive motor 71 rotates the nut member 70, and the screw shaft 68 is interposed. Since the motion shaft 63 is moved up and down, the rotational motion and the vertical motion can be continuously or synchronously performed to achieve a desired motion profile, shorten the motion tact, and improve productivity. Since the first and second expensive direct drive motors 64 and 71 need to be installed, there is a problem that the apparatus cost increases.

  In view of the above-described conventional problems, it is an object of the present invention to provide a transfer apparatus that can shorten the operation tact and increase the speed, can be configured compactly, and can reduce the cost.

  The transfer device according to the present invention fixes a transfer arm having a holding unit for an object at a tip portion to one end of an operating shaft, and inserts the operating shaft into a hollow portion of a direct drive motor having a hollow portion. The rotating part of the drive motor and the operating shaft are coupled so that they can move relative to each other in the axial direction and cannot be rotated relative to each other. Then, one end side of the screw shaft whose intermediate portion is screwed to the nut member is inserted into a hollow portion formed at the other end portion of the operation shaft, and the other end is coupled to the servo motor.

  According to this configuration, the rotation axis is moved by the direct drive motor and the movement axis is moved in the axial direction by the servo motor. Therefore, the rotation movement and the axial movement are performed continuously or synchronously. By realizing a desired operation profile, the operation tact can be shortened and the transfer speed can be increased. For example, what conventionally took about 4 seconds for one reciprocating operation can be shortened to about 2 seconds. The transfer arm that requires rotational torque is rotated by a direct drive motor, but the screw shaft that does not require large rotational torque is rotated by an inexpensive servo motor, so it is inexpensive. be able to. Furthermore, since the operating shaft and the nut member are disposed in the hollow portion of the direct drive motor and one end side of the screw shaft is inserted into the hollow portion of the other end portion of the operating shaft, the axial direction can be made compact. . Thus, high speed and compactness can be achieved, and further cost reduction can be achieved.

  Also, if the nut member is fixed to the other end of the operating shaft and a control means for controlling the rotational position and the axial position of the operating shaft by controlling the direct drive motor and the servo motor is provided, the nut member is simply moved to the operating shaft. Since the nut member is fixed to the other end, the structure for supporting the nut member so as not to freely rotate and to be movable in the axial direction is unnecessary, and a simple and inexpensive structure can be obtained. Also, for example, when the servo motor rotates, the direct drive motor is controlled so that the operating axis does not rotate, and the rotational position is controlled to a desired position. The rotation position of the operating axis and the axial position of the operating axis are properly controlled by controlling the direct drive motor and the servo motor in a correlated manner, such as rotating the servo motor in synchronization with each other. can do.

  In addition, when a detection member is provided at the end of the extended portion that extends from the other end of the nut member, and a detection means that detects the detection member corresponding to the movement end of the operation shaft is provided, the movement end of the operation shaft is detected. Thus, the operation safety can be ensured by forcibly stopping the operation.

  According to the present invention, since the direct drive motor and the servo motor rotate the operation shaft and move in the axial direction, the rotation tact and the axial motion can be performed continuously or synchronously to shorten the operation tact. One motor that does not require a large rotational torque can be configured at low cost because it uses a servo motor, and further, an operating shaft and a nut member are disposed in the hollow portion of the direct drive motor, Since one end side of the screw shaft is inserted into the hollow portion at the other end portion of the operation shaft, the screw shaft can be made compact, and high speed and compactness can be achieved with an inexpensive configuration.

  Hereinafter, an embodiment of the transfer apparatus of the present invention will be described in detail with reference to FIGS.

  In FIG. 1, reference numeral 1 denotes a transfer device, which has a transfer arm 2 having holding parts 3 for holding an object to be transferred at both ends, and a support boss part 4 provided at the center of the transfer arm 2. The upper end portion of the operating shaft 5 is fixed to the above. Reference numeral 6 denotes a direct drive motor that rotationally drives the operating shaft 5. A hollow portion 7 is provided in the shaft center portion, and a lower portion of the operating shaft 5 is inserted into the hollow portion 7. A rotating disk 8 is fixed to the upper end of a rotating part (rotor part) on the inner peripheral side of the direct drive motor 6, and a ball spline sleeve 9 as a spline mechanism fixed to the inner periphery of the rotating disk 8 is an outer periphery of the operating shaft 5. Is engaged with the spline forming portion so as not to rotate but to be movable in the axial direction.

  A nut member 11 constituting a ball screw feed mechanism is connected to the lower end of the operation shaft 5 in a vertically free manner via a thrust bearing 91 on the lower end surface of the operation shaft 5, and the nut member 11 is connected to the spline sleeve. 10 is supported so that it cannot rotate but can move up and down. An intermediate portion of a screw shaft 12 including a ball screw shaft is screwed onto the nut member 11, and an upper end portion of the screw shaft 12 is inserted into a hollow portion 13 formed at the lower end portion of the operation shaft 5. The vicinity of the lower end of the screw shaft 12 is rotatably supported by a bearing 14, and the lower end of the screw shaft 12 is coupled to an AC servo motor 15 via a shaft coupling 16 that can absorb misalignment.

  In FIG. 1, 17 is a support bracket for supporting the fixed portion on the outer peripheral side of the direct drive motor 5, 18 is a base plate on which the spline sleeve 10 and the bearing 14 are mounted, 19 is mounted on the base plate 18 and the AC sabot motor 15, and is transferred. It is a frame that supports the entire mounting apparatus 1.

  Next, the transfer operation by the transfer apparatus 1 having the above configuration will be described with reference to FIGS. First, as shown by the solid line in FIG. 3, the solid lines in FIG. 1 are shown with the holding parts 3 at both ends of the transfer arm 3 facing the first delivery parts 21a and 21b of the object 20 to be transferred. The transfer arm 2 is lowered as shown by and the object 20 is held by the respective holding portions 3. Next, the screw shaft 12 is rotated by the AC servo motor 15, the nut member 11 is moved upward, and the transfer arm 2 is indicated by an imaginary line in FIG. As shown in FIG. Next, the operation shaft 5 and the transfer arm 2 are rotated by 90 ° as indicated by the arrow b by the direct drive motor 6 via the turntable 8 and the ball spline 9, and the holding portion 3 at the tip of the transfer arm 2 is moved to It positions above 2 delivery parts 22a and 22b. Next, the screw shaft 12 is reversely rotated by the AC servo motor 15 to move the nut member 11 downward, and the transfer arm 2 is again shown by the solid line in FIG. Then, the object 20 is lowered to a predetermined height position, and the object 20 is delivered to the second delivery units 22a and 22b.

  When the object 20 is delivered to the second delivery parts 22a and 22b, the screw shaft 12 is rotated by the AC servo motor 15 to move the nut member 11 upward, and the transfer arm 2 is moved to the arrow via the operation shaft 5. As shown in d, it is raised to a predetermined height position. Next, the operating shaft 5 and the transfer arm 2 are reversely rotated by 90 ° as indicated by an arrow e by the direct drive motor 6 through the rotating disk 8 and the ball spline 9, and the holding portion 3 at the tip of the transfer arm 2 is moved. It positions above the 1st delivery parts 21a and 21b. Thereafter, when the object 20 is transferred again, the screw shaft 12 is reversely rotated by the AC servo motor 15 to move the nut member 11 downward, and the transfer arm 2 is moved via the operation shaft 5 as indicated by an arrow f. As indicated by a solid line in FIG. 1 again, the object 20 is lowered to a predetermined height position and the object 20 is held by the respective holding portions 3. By repeating the above operation, the object 20 can be sequentially transferred from the first delivery unit 21a, 21b to the second delivery unit 22a, 22b. The AC servo motor 15 and the direct drive motor 6 can be operated synchronously so that the vertical movement of the transfer arm 2 and the rotating shaft can be performed in parallel.

  According to the above embodiment, the direct drive motor 6 rotates the operating shaft 5 via the ball spline 9, the AC servomotor 15 rotates the screw shaft 12, and the operating shaft is connected via the nut member 11. 5 is moved in the axial direction, and both the rotational motion and the axial motion are driven by a motor. Therefore, the motion can be realized by realizing a desired motion profile by performing both motions continuously or synchronously. The tact time can be shortened, the transfer speed can be increased, and the productivity can be improved.

  Moreover, the transfer arm 2 that requires rotational torque is rotated by the direct drive motor 6, but the screw shaft 12 that does not require large rotational torque is rotated by an inexpensive AC servomotor 15. Therefore, it can be constructed at a lower cost than those in which both are moved by a direct drive motor as in the conventional example. Further, the operating shaft 5 and the nut member 11 are disposed in the hollow portion 7 of the direct drive motor 6, and one end side of the screw shaft 12 is inserted into the hollow portion 13 at the other end portion of the operating shaft 5. It can be configured compactly.

  Next, another embodiment of the transfer device of the present invention will be described with reference to FIG. In addition, the same component as the component of the said embodiment attaches | subjects the same referential mark, description is abbreviate | omitted, and only a different point is demonstrated.

  In the above embodiment, the nut member 11 is supported by the spline sleeve 10 so as not to rotate and to be movable in the axial direction. However, in this embodiment, the nut member 11 is fixed to the lower end portion of the operation shaft 5. That is, a fastening fixing portion 23 that is externally fitted to the outer periphery of the lower end portion of the operating shaft 5 and can be fastened and fixed is provided at the upper end portion of the nut member 11. A control means 24 is provided for controlling the direct drive motor 6 and the AC servo motor 15 in correlation to control the rotational position and the axial position of the operating shaft 5.

  Further, a detection member 26 made of a ferromagnetic material such as iron is attached to the end of the extension portion 25 extending from the other end of the nut member 11, and the side thereof is covered corresponding to the upper and lower moving ends of the operation shaft 5. Detection means 27a and 27b such as a reed switch for detecting the detection member 26 are provided.

  In FIG. 4, 28 is a support frame disposed around the rotating disk 8, 30 is a base plate connected to the support frame 28 via a plurality of support rods 29 disposed around the direct drive motor 6, Reference numeral 31 denotes a support plate that supports a fixed portion on the outer periphery of the direct drive motor 6 on the base plate 30, and 33 is connected via a plurality of connecting rods 32 that are suspended from the inner periphery of the support plate 31. Is supported by a mounting bracket 34, and the support plate 33 is provided with a bearing 14 that rotatably supports the vicinity of the lower end of the screw shaft 12. Reference numeral 35 denotes a cover surrounding the periphery of the upper end portion of the operation shaft 5.

  According to the configuration of the present embodiment, since the nut member 11 is simply fixed to the lower end portion of the operation shaft 5 by the fastening and fixing portion 23, the nut member 11 cannot be rotated and axially as in the above embodiment. The spline sleeve 10 that is movably supported on the shaft is not required, so that a simple and inexpensive configuration can be obtained, and the direct drive motor 6 and the servo motor 15 are controlled in correlation, whereby the rotational position of the operating shaft 5 And the axial position of the operation shaft 5 can be appropriately controlled without affecting each other.

  Further, since the detected member 26 provided at the lower end of the extension 25 extending from the lower end of the nut member 11 is detected by the detecting means 27a and 27b, the moving end of the operating shaft 5 can be detected. By making the shaft 5 forcibly stop when it reaches the moving end, the safety of the operation can be ensured.

  In the above description of the embodiment, the configuration in which the screw shaft 12 and the AC servomotor 15 are coupled via the shaft coupling 16 is shown. However, the output shaft of the AC servomotor 15 is configured by the screw shaft 12. Needless to say, since the shaft coupling 16 and the bearing 14 can be omitted, the structure can be further reduced.

  In the transfer device of the present invention, the rotation of the operation shaft and the movement in the axial direction are performed by the direct drive motor and the servo motor. The motor can be shortened, the transfer speed can be increased, and a servo motor is used for one motor that does not require a large rotational torque. Therefore, the present invention is useful for a transfer device for a substrate or semiconductor wafer transfer device in an electronic component production line, a manufacturing line for other various articles, or the like.

It is a vertical front view of the transfer apparatus of one Embodiment of this invention. It is a vertical front view of the operation state of the transfer apparatus of the embodiment. It is a vertical front view of the operation state of the transfer apparatus of the embodiment. It is a principal part top view of the transfer apparatus of other embodiment of this invention. It is a vertical front view of the transfer apparatus of a prior art example. It is a vertical front view of the transfer apparatus of another prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Transfer apparatus 2 Transfer arm 3 Holding part 5 Operation shaft 6 Direct drive motor 7 Hollow part 8 Turntable 9 Ball spline (spline mechanism)
DESCRIPTION OF SYMBOLS 11 Nut member 12 Screw shaft 13 Hollow part 15 AC servomotor 23 Fastening fixing part 24 Control means 25 Extension part 26 Detected member 27a, 27b Detection means

Claims (3)

  A transfer arm having a holding portion for an object at the tip is fixed to one end of the operating shaft, and the operating shaft is inserted into the hollow portion of the direct drive motor having a hollow portion. Are connected to the other end of the operating shaft so that they can be rotated relative to each other or fixed, and the intermediate part is screwed to the nut member. A transfer apparatus, wherein one end side of the combined screw shaft is inserted into a hollow portion formed at the other end portion of the operation shaft, and the other end is coupled to a servo motor.   2. The shifter according to claim 1, further comprising a control means for fixing the nut member to the lower end portion of the operating shaft and controlling the rotational position and the axial position of the operating shaft by controlling the direct drive motor and the servo motor. Mounting device.   3. The detection member is provided at the end of the extended portion extending from the other end of the nut member, and detection means for detecting the detection member is provided corresponding to the moving end of the operating shaft. The transfer apparatus described.

Images