Conveying equipment

Abstract

Provided is a conveyance device capable of achieving high-speed conveyance of a workpiece through arm weight reduction and inertial moment reduction. The conveyance device 100 capable of rotating and linearly moving an arm 121 comprises: a rotary motion mechanism 101 which has a first rotary shaft 108 capable of rotating about a first axis 103; a rotation transmission mechanism 109 which is connected to the first rotary shaft 108 and is capable of rotating the arm 121 when the rotation transmission mechanism 109 is caused to rotate about a second axis 106 in response to rotation of the first rotary shaft 108; and a linear movement mechanism 104 which is capable of linearly moving the arm 121. The linear movement mechanism 104 is disposed on the inner side of the rotation transmission mechanism 109 in such a manner as not to rotate in response to rotation of the first rotary shaft 108.

Description

Conveying device The present invention relates to a conveying device and a pick-and-place device that can transport workpieces (objects to be worked on) at high speed and can rotate and / or move the workpieces to any desired position. Various conveying devices have been proposed that enable pick-and-place workpieces by using a drive source such as a motor to cause an arm to rotate and / or move in a straight line. Patent Document 1 discloses a four-axis horizontal articulated robot (SCARA robot) having a first arm rotated horizontally around a first axis by a first motor, a second arm connected to the tip of the first arm and rotated horizontally around a second axis by a second motor, and an axis extending vertically downward from the tip of the second arm, which is moved up and down in the third axial direction by third and fourth motors, respectively, and rotated horizontally around a fourth axis, with a chuck for gripping a workpiece attached to the lower end of the axis. Patent Document 2 discloses a conveying device having an arm mechanism having a plurality of link bars and a substrate holding part, a first motor for extending and retracting the arm mechanism, a first cable connected to the first motor, a conveying device body that houses the first motor, a first gear provided on the conveying device body, a second motor for rotating the conveying device body and the arm mechanism, a second cable connected to the second motor, and a second gear that meshes with the first gear and is provided on the output shaft of the second motor. Patent Document 3 discloses a two-axis rotary drive device having a first drive motor, a first shaft, a second drive motor attached to the first shaft, a second shaft, and a housing for wiring that supplies a drive signal to the second drive motor. The disclosure states that the wiring is housed in the housing such that when the first drive motor is driven to rotate in one direction, the wiring is wound around the second drive motor, and when the first drive motor is driven to rotate in the other direction, the winding of the wiring is released. JP-A-5-237781 International Publication No. 2011 / 010448 JP-A-11-207684 When the horizontal articulated robot of Patent Document 1 rotates the first arm and the second arm horizontally, a second motor is provided at the tip of the first arm, and third and fourth motors are provided at the tip of the second arm. Therefore, there is a problem that the weight of the arm increases, and further the moment of inertia increases, making it difficult to transfer the workpiece at high speed. When the second motor of the transfer device of Patent Document 2 is driven and the arm mechanism is rotated, the transfer device main body rotates together with the arm mechanism. Therefore, since the first motor mounted in the transfer device main body also rotates at the same time, the moment of inertia increases and it is not easy to transfer the workpiece at high speed. Further, the first cable connected to the first cable winds around the transfer device, and there is a problem that a load is applied to the first cable and the first cable is disconnected. Similarly to the transfer device of Patent Document 2, when the first drive motor of the two-axis rotation drive device of Patent Document 3 is driven, the second drive motor attached to the first shaft also rotates. Therefore, the moment of inertia increases and it is not easy to transfer the workpiece at high speed. Further, since the wiring is repeatedly wound and the wound state is released, a load is applied to the wiring, and there is a problem that disconnection of the wiring cannot be completely prevented. Therefore, an object of the present invention is to provide a transfer device that can transfer a workpiece at high speed, can transfer the workpiece to an arbitrary position, and can prevent problems including disconnection of wiring for supplying a signal for operating the arm. According to one aspect of the present invention, a transfer device capable of pivoting and linearly moving an arm includes a rotational movement mechanism having a first rotation axis rotatable about a first axis, and a rotational transmission mechanism connected to the first rotation axis. The rotational transmission mechanism is configured to rotate the arm by rotating the rotational transmission mechanism about a second axis in response to rotation of the first rotation axis. And a linear motion mechanism capable of linearly moving the arm, and the linear motion mechanism is arranged inside the rotational transmission mechanism so as not to rotate in response to rotation of the first rotation axis. According to one specific example of the present invention, in a conveying device, a pair of support columns are connected to a rotational transmission mechanism, and an arm is positioned between the pair of support columns to enable rotational movement. According to one specific example of the present invention, in a conveying device, an arm is capable of moving in a straight line along a pair of support columns in response to a linear motion mechanism. According to one specific example of the present invention, in a conveying device, the linear motion mechanism is equipped with an arm gripping portion that grips the arm and allows for linear movement, thereby enabling the arm to move in a straight line in response to the linear motion mechanism. According to one specific example of the present invention, in a conveying device, a bearing is provided between the linear motion mechanism and the arm, so that when the rotation transmission mechanism is rotated in response to the rotation of the first rotating shaft, the linear motion mechanism does not rotate in response to the rotation of the first rotating shaft. According to one specific example of the present invention, in a conveying device, the rotational transmission mechanism includes a gear that rotates about a second axis, a hollow portion is provided inside the gear, and a linear motion mechanism is arranged in the hollow portion. According to one specific example of the present invention, in a conveying device, the rotational transmission mechanism is a turret connected to a first rotating shaft, the turret having a plurality of cylindrical pinions on its end face, and at least one of the plurality of cylindrical pinions contacts a gear, thereby allowing the gear to rotate in response to the rotation of the first rotating shaft. According to one specific example of the present invention, in a conveying device, the linear motion mechanism includes a second motor having a second rotation axis that can rotate about a second axis, and the arm is capable of linear motion in response to the rotation of the second rotation axis. According to one specific example of the present invention, in a conveying device, the linear motion mechanism further comprises a screw shaft and a nut engaged with the screw shaft, one end of the screw shaft is connected to the second rotating shaft so that the screw shaft rotates in response to the second rotating shaft, and the nut moves linearly as the screw shaft rotates, thereby enabling the arm to move linearly. According to one specific example of the present invention, in a conveying device, a plurality of balls inserted between a screw shaft and a nut roll, thereby enabling the nut to move in a straight line. According to the present invention, since the linear motion mechanism is located inside the rotational transmission mechanism, the weight of the arm can be reduced, and the arm can be moved in a straight line at high speed. Furthermore, since the linear motion mechanism is positioned so as not to rotate in response to the rotation of the rotational motion mechanism, the moment of inertia during the arm's pivoting motion can be reduced, and the arm can pivot at high speed. In addition, since the linear motion mechanism does not rotate in response to the rotation of the rotational motion mechanism, the wiring supplying signals to the linear motion mechanism does not get tangled, thus preventing malfunctions including wire breakage. Further objectives, features, and advantages of the present invention will become apparent from the following description of embodiments relating to the accompanying drawings. This is a cross-sectional view of a conveying device as one embodiment of the present invention, viewed from the side. This is a cross-sectional view of the conveying device of Figure 1, viewed from the front. This is a perspective view of the conveying device of Figure 1, including a partial cross-sectional view. This is a perspective view of the conveying device of Figure 1. This is a cross-sectional view of the conveying device of Figure 1, viewed from the side when the arm of the conveying device of Figure 1 is lowered. The following describes embodiments of the present invention with reference to the drawings, but the present invention is not limited to these embodiments. Figures 1 to 5 show a conveying device 100, which is one embodiment of the present invention. The conveying device 100 is equipped with a first arm 121, which can be rotated and moved in a straight line. An output shaft 124 is connected to the tip of the first arm 121, and the output shaft 124 grips (picks up) a workpiece (object to be worked on) at the end opposite to the end to which the first arm 121 is connected, and conveys and places (places) the workpiece by the rotational and / or straight line movement of the first arm 121. The conveying device 100 is also equipped with a second arm 122 to support the output shaft 124, and a bearing 123 to enable the output shaft 124 to move smoothly in a straight line. The conveying device 100 includes a rotational motion mechanism 101 having a first rotation shaft 108 that can rotate about a first axis 103, a rotation transmission mechanism 109 connected to the first rotation shaft 108 and capable of pivoting the first arm 121 by rotating the rotation transmission mechanism 109 about a second axis 106 in response to the rotation of the first rotation shaft 108, and a linear motion mechanism 104 capable of moving the first arm 121 in a straight line. The linear motion mechanism 104 is positioned inside the rotation transmission mechanism 109 so as not to rotate in response to the rotation of the first rotation axis 108 of the rotation motion mechanism 101. That is, when the first rotation axis 108 of the rotation motion mechanism 101 rotates around the first axis 103, causing the rotation transmission mechanism 109 to rotate around the second axis 106, the first arm 121 pivots accordingly, but the linear motion mechanism 104 does not rotate. By positioning the linear motion mechanism 104 inside the rotation transmission mechanism 109 in this way, the weight of the first arm 121 can be reduced, making it easier to move the first arm 121 in a straight line at high speed. Furthermore, by preventing the linear motion mechanism 104 from rotating in response to the rotation of the first rotation axis 108, the moment of inertia of the first arm 121 is reduced, making it easier to move the first arm 121 pivot at high speed. The rotational motion mechanism 101 may be configured with a first motor 102 so as to be able to rotate the first rotating shaft 108. Alternatively, the rotational motion mechanism 101 may be configured to rotate the first rotating shaft 108 by adjusting the rotational speed of the first motor 102 by including a reduction gear 107. The rotation transmission mechanism 109 is connected to the first rotating shaft 108 of the rotational motion mechanism 101 via a first clamp collar 129 and comprises a drive unit that rotates in response to the first rotating shaft 108 and a driven unit that rotates along with the rotation of the drive unit. The drive unit and the driven unit may be composed of gears, and the rotation of the drive unit may be transmitted to the driven unit by the meshing of the teeth of the drive unit and the teeth of the driven unit, or the rotation of the drive unit may be transmitted to the driven unit by using a timing belt. Depending on the position, orientation, etc., relationship between the rotational motion mechanism 101 and the rotation transmission mechanism 109, various types of gears such as spur gears, helical gears, and bevel gears can be used as the gears of the drive unit and the driven unit. A pair of support columns 119 are connected to the driven part of the rotation transmission mechanism 109, and the first arm 121 is positioned between the pair of support columns 119 as shown in Figure 4. As a result, when the driven part of the rotation transmission mechanism 109 rotates, the pair of support columns 119 also rotate together, and the first arm is pushed by one of the pair of support columns 119, allowing it to pivot in both directions. Since the first arm 121 is positioned between the pair of support columns 119 as described above, it can move in a straight line along the pair of support columns 119 in response to the straight-line motion mechanism 104. The straight-line motion mechanism 104 can be an air cylinder, an electric cylinder, etc. By moving the cylinder in a straight line along the second axis 106 pneumatically or electrically, the first arm 121 connected to the cylinder can be moved in a straight line accordingly. Alternatively, the straight-line motion mechanism 104 can consist of a screw shaft and a nut. By converting the rotation of the screw shaft about the second axis 106 into a straight-line motion by the nut, the first arm 121 connected to the nut can be moved in a straight line. The linear motion mechanism 104 includes an arm clamping portion 117 that clamps the first arm 121. The arm clamping portion 117 does not rotate in response to the rotation transmission mechanism 109, but is configured to move in a straight line along the second axis 106 in response to the linear motion by the linear motion mechanism 104. When the arm clamping portion 117 moves in a straight line, the first arm 121 is able to move in a straight line in response to the arm clamping portion 117. An arm bearing 118 is provided between the linear motion mechanism 104 and the first arm 121. When the drive unit of the rotation transmission mechanism 109 rotates in response to the rotation of the first rotation shaft 108 of the rotation motion mechanism 101, and the driven unit of the rotation transmission mechanism 109 rotates accordingly, the first arm 121 pivots in accordance with the rotation of the driven unit of the rotation transmission mechanism 109. However, the arm bearing 118 prevents the torque of the driven unit of the rotation transmission mechanism 109 from being transmitted to the linear motion mechanism 104, thus preventing the linear motion mechanism 104 from rotating. Since the linear motion mechanism 104 does not rotate, the moment of inertia when the rotation transmission mechanism 109 is rotating can be reduced. The driven portion of the rotation transmission mechanism 109 may consist of a gear 112 that rotates around a second axis 106. A hollow portion 120 is provided inside the gear 112, and a linear motion mechanism 104 is arranged in the hollow portion 120. As shown in Figures 1 and 2, the linear motion mechanism 104 is positioned so as not to come into contact with the gear 112 and does not rotate in conjunction with the rotation of the gear 112. The drive unit of the rotation transmission mechanism 109 may consist of a turret 111 connected to the first rotating shaft 108 of the rotational motion mechanism 101 via a first clamp collar 129. A plurality of cylindrical pinions 110 are provided on one end face of the turret 110. At least one of the plurality of cylindrical pinions 110 contacts the gear 112 of the driven part of the rotation transmission mechanism 109, so that in response to the rotation of the first rotating shaft 108 of the rotational motion mechanism 101, the plurality of cylindrical pinions 110 provided on the turret 111 of the drive unit of the rotation transmission mechanism 109 rotate, and the gear 112 of the driven part of the rotation transmission mechanism 109 rotates. By configuring the rotation transmission mechanism 109 in this way, the first arm 121 can be rotated to any pivot angle, and a workpiece can be transported to any position. Furthermore, at least two of the multiple cylindrical pinions 110 contact the teeth of the gear 112 of the driven part of the rotation transmission mechanism 109 by gripping them, thereby eliminating backlash and allowing the first arm 121 to be rotated to any desired pivot angle with even greater precision. The rotational transmission mechanism 109 may be positioned on a base 125 and covered by a housing 126, as shown in Figures 1 to 3. The rotational transmission mechanism 109 may also be equipped with a gear bearing 128 to allow smooth rotation relative to the housing 126. Furthermore, an oil seal 128 may be provided between the gear 112 and the housing 126 to ensure smooth contact between the multiple cylindrical pinions 110 and the gear 112 by injecting oil into the housing 126 and to prevent oil leakage. The contact between the multiple cylindrical pinions 110 and the gear 112 may be sliding contact or rolling contact. By using sliding contact, the cylindrical pinion can be constructed from a single component, thereby increasing the rigidity of the cylindrical pinion and reducing manufacturing costs. In the case of rolling contact, the cylindrical pinion 110 may be a cam follower / roller follower or a bearing. By using rolling contact, the friction between the cylindrical pinion 110 and the gear 112 can be reduced, and rotation can be transmitted from the cylindrical pinion 110 to the gear 112 with high efficiency. The linear motion mechanism 104 may include a second motor 105 having a second rotating shaft 113 that is rotatable about a second axis 106. Alternatively, the rotational motion mechanism 101 may be equipped with a reduction gear to adjust the rotational speed of the second motor 105 and rotate the second rotating shaft 113. The linear motion mechanism 104 converts the rotation by the second rotating shaft 113 into linear motion, enabling the first arm 121 to move in a straight line. The second rotating shaft 113 of the linear motion mechanism 104 may be enclosed by a cylindrical body and connected to the cylindrical body via a second clamp collar 130. The linear motion mechanism 104 may also include a screw shaft 115 and a nut 116 engaged with the screw shaft 115. One end of the screw shaft 115 is connected to the cylindrical body via a coupling 114, and when the second rotating shaft 113 of the second motor 105 of the linear motion mechanism 104 rotates, the screw shaft 115 also rotates accordingly. The rotation of the screw shaft 115 is converted into linear motion of the nut 116, enabling the first arm 121 connected to the nut 116 to move in a straight line. An arm clamping portion 117 that clamps the first arm 121 is connected to the nut 116. The arm clamping portion 117 does not rotate in response to the rotation of the gear 112, and is configured to move in a straight line along the second axis 106 relative to the second motor 105. When the second rotation shaft 113 rotates and the screw shaft 115 rotates, the nut 116 moves in a straight line along the second axis 106 together with the arm clamping portion 117 without rotating in response. Then, the first arm 121 also moves in a straight line along the pair of support columns 119 in accordance with the straight line movement of the nut 116 and the arm clamping portion 117. Figures 1 and 5 show that the rotation of the screw shaft 115 is converted into vertical linear motion by the nut 116, causing the arm clamping portion 117 and the first arm 121 to move upward and downward, respectively. By configuring the linear transmission mechanism 104 in this way, the first arm 121 can be moved to any height, and the workpiece can be transported to any height. Multiple balls may be inserted between the screw shaft 115 and the nut 116 of the linear motion mechanism 104. This constitutes a so-called ball screw. When the screw shaft 115 rotates, the multiple balls roll between the screw shaft 115 and the nut 116, allowing the nut 116 to move smoothly in a straight line. The conveying device 100 can also operate the rotational motion mechanism 101 and the linear motion mechanism 104 simultaneously. That is, by rotating the first rotation axis 108 of the rotational motion mechanism 101, the first arm 121 can be rotated via the rotational transmission mechanism 109, while by operating the linear motion mechanism 104, the first arm 121 can be moved in a straight line. Although the above description is based on specific embodiments, it will be apparent to those skilled in the art that the present invention is not limited thereto, and various changes and modifications can be made within the scope of the principles of the present invention and the appended claims. 100 Conveying device 101 Rotational motion mechanism 102 First motor 103 First axis 104 Straight-line motion mechanism 105 Second motor 106 Second axis 107 Reducer 108 First axis of rotation 109 Rotational transmission mechanism 110 Cylindrical pinion 111 Turret 112 Gear 113 Second axis of rotation 114 Coupling 115 Screw shaft 116 Nut 117 Arm clamping section 118 Arm bearing 119 Pillar 120 Hollow part 121 First Arm 122 Second Arm 123 Output bearing 124 Output shaft 125 base 126 Housing 127 Gear bearing 128 Oil seal 129. First clamp collar 130 Second clamp collar

Claims

Page 1 of 2 pages of Claims 1. A conveyor device which operates an arm to rotate, and moves linearly, which consists of: a rotary motion mechanism which includes a first rotating shaft which can rotate around the first axis; a rotational transmission mechanism which includes a drive unit which rotates in response to the first rotating shaft and a driven unit which rotates in response to the rotation of the drive unit, and is configured to rotate the arm by a receiver unit connected to the driven unit when the driven unit rotates around a second axis in response to the rotation of the first rotating shaft; and a linear motion mechanism which moves the arm linearly, whereby the linear motion mechanism is arranged inside the driven unit and does not rotate in response to the rotation of the first rotating shaft.

2. A conveyor device according to Claim 1, in which the receiver unit is a pair of supporting units, and the arm is configured to rotate by being positioned between the pair of supporting units.

3. A conveyor device according to Claim 2, in which the arm moves linearly along the pair of supporting units in response to the linear motion mechanism. 4.Conveyor devices under claim 3, where the linear motion mechanism includes an inter-arm insert which is inserted between the arms and moves in a linear fashion, in which case the arms move in a linear fashion in response to the linear motion mechanism.

5. Conveyor devices under claims 1 to 4, where bearings are provided between the linear motion mechanism and the arms, in which case, if the driven unit rotates in response to the rotation of the first rotating shaft, the linear motion mechanism is arranged so that it does not rotate in response to the rotation of the first rotating shaft.

6. Conveyor devices under claims 1 to 5, where the driven unit includes a gear which rotates around a second axis, a hollow part is provided inside the gear, and the linear motion mechanism is provided in the hollow part. Page 2 of page 2 of 7.

8. Any conveyor under claim 1 through 7, in which the linear motion mechanism includes a second motor which includes a second rotating shaft which includes a number of small cylindrical gears on the end surfaces of the hexagonal turntable, and at least one of a number of small cylindrical gears engaged in contact with the gears to cause the gears to rotate in response to the rotation of the first rotating shaft.

9. Any conveyor under claim 1 through 7, in which the linear motion mechanism includes a second motor which includes a second rotating shaft which can rotate around a second axis, and the linear motion mechanism moves the arm linearly in response to the rotation of the second rotating shaft.

10. Any conveyor under claim 8, in which the linear motion mechanism includes an additional threaded shaft and a screw thread which is engaged with the threaded shaft, one end of the threaded shaft is connected to the second rotating shaft to cause the threaded shaft to rotate in response to the second rotating shaft, and the screw thread moves linearly in response to the rotation of the second rotating shaft to cause the arm to move linearly.A conveying device according to claim 9, in which a certain number of balls placed between a threaded shaft and a threaded nut roll to move the threaded nut in a linear fashion;