Vertical multi-joint robot

Abstract

To provide a vertical multi-joint robot in which a weight of a wrist unit is light and required space is saved while employing double hand.SOLUTION: A vertical multi-joint robot 100 includes: a wrist unit 136 connected to a holding arm 132 and mounted with a first hand 142 and a second hand 146; a fifth shaft 138 that rotates the wrist unit; a sixth shaft 140 and a seventh shaft 144 that rotate the first hand and the second hand; a fifth shaft motor 148, a sixth shaft motor 150, and a seventh shaft motor 152 stored in the holding arm and arranged in parallel; a first intermediate shaft 160 that is arranged coaxially with the fifth shaft and receives a drive force of the sixth shaft motor; a second gear 162b that is attached to the sixth shaft and meshes with a first gear 162a attached to the first intermediate shaft; a second intermediate shaft 164 that is arranged coaxially with the fifth shaft and the first intermediate shaft and receives a drive force of the seventh shaft motor; and a fourth gear 166b that is attached to the seventh shaft and meshes with a third gear 166a attached to the second intermediate shaft.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a vertical articulated robot having double hands. [Background technology]

[0002] Conventionally, horizontal articulated robots (SCARA robots) have often been used as robots for transporting substrates. Furthermore, the end of the arm of a horizontal articulated robot is equipped with an end effector such as a hand for placing a substrate (see, for example, Patent Document 1).

[0003] Patent Document 1 describes a so-called double-handed robot. In this double-handed robot, two hands are connected to the tip of an arm in two tiers, one above the other. Each of the two hands can rotate independently around a hand rotation axis at the tip of the arm. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-659 Summary of the Invention [Problem to be solved by the invention]

[0005] However, Patent Document 1 merely discloses a configuration in which a horizontal articulated robot employs a double hand. Moreover, since horizontal articulated robots often have limited uses, it is common to design specialized machines for each application. However, designing specialized machines means that the applications are limited, which means that manufacturing costs are higher compared to standard (general-purpose) vertical articulated robots.

[0006] Therefore, it is conceivable to adopt a double hand in a vertical articulated robot. However, a vertical articulated robot has a wrist unit at the end of an arm, and a hand is attached to the wrist unit. In a horizontal articulated robot such as that shown in Patent Document 1, the hand is attached directly to the arm, so it was easy to provide a hand rotation mechanism within the arm.

[0007] However, in the case of vertically articulated robots, in order to rotate the two hands attached to a rotating wrist unit, it was previously necessary to place two hand rotation mechanisms on the wrist unit, which posed the problem of making the wrist unit very heavy.

[0008] In view of the above problems, the present invention aims to provide a vertically articulated robot that employs a double hand while achieving a lightweight and space-saving wrist unit. [Means for solving the problem]

[0009] In order to solve the above problems, a typical configuration of a vertical articulated robot according to the present invention includes a first arm, a wrist unit connected to the first arm and having a first hand and a second hand attached thereto, a wrist axis that rotates the wrist unit in a direction inclined relative to the first arm, a first hand axis that is attached to the wrist unit and rotates the first hand in a direction perpendicular to the direction of rotation of the wrist unit, a second hand axis that is attached to the wrist unit and rotates the second hand coaxially with the first hand axis, and a drive source for the wrist axis, the first hand axis, and the second hand axis that is housed in the first arm and The robot is characterized by comprising a wrist shaft motor, a first hand shaft motor, and a second hand shaft motor arranged in parallel to each other, a first intermediate shaft arranged coaxially with the wrist shaft and receiving driving force from the first hand shaft motor, a first gear attached to the first intermediate shaft, a second gear attached coaxially to the first hand shaft and meshing with the first gear, a second intermediate shaft arranged coaxially with the wrist shaft and the first intermediate shaft and receiving driving force from the second hand shaft motor, a third gear attached coaxially to the second intermediate shaft, and a fourth gear attached coaxially to the second hand shaft and meshing with the third gear. [Effects of the Invention]

[0010] According to the present invention, it is possible to provide a vertically articulated robot that employs a double hand while achieving a lightweight wrist unit and space saving. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a perspective view showing the overall configuration of a vertical articulated robot according to an embodiment of the present invention. [Figure 2] 2 is a partial cross-sectional view illustrating a main part of the holding arm (first arm) of FIG. 1. FIG. [Figure 3] 3 is an enlarged partial cross-sectional view showing a part of the holding arm (first arm) of FIG. 2. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0012] Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Dimensions, materials, and other specific values ​​shown in the embodiments are merely examples for facilitating understanding of the invention and, unless otherwise specified, do not limit the present invention. In this specification and drawings, elements having substantially the same functions and configurations are designated by the same reference numerals to avoid redundant explanation, and elements not directly related to the present invention are not shown.

[0013] 1 is a perspective view showing the overall configuration of a vertical articulated robot 100 according to an embodiment of the present invention. The vertical articulated robot 100 is an industrial robot used, for example, to transport a workpiece (such as a substrate).

[0014] In brief, vertically articulated robot 100 in this embodiment differs from a typical vertically articulated robot in that the first axis rotates in a different direction, and the main operating range of the lower arm and upper arm is upward. Vertically articulated robot 100 is, for example, a seven-axis robot, and includes base 108, first axis 110, swivel frame 112, second axis 114, lower arm 116, third axis 118, and upper arm 120. As will be described later, upper arm 120 has connecting arm 130, fourth axis 134, and holding arm (first arm) 132, and rotates as a whole about third axis 118 and fourth axis 134.

[0015] The base 108 is installed on the floor of a factory, etc. A connector 124 to which the harness is connected is attached to a side surface 122 of the base 108. Note that the connector 124 can also be attached to other side surfaces 126, 128 of the base 108, taking into consideration the direction in which the harness is pulled out.

[0016] When the base 108 is installed on a floor, the first shaft 110 is supported in a direction parallel to the installation surface 109, which is the installation surface (hereinafter referred to as the horizontal direction). The swivel frame 112 rotates about the first shaft 110. The second shaft 114 is supported by the swivel frame 112 in a direction perpendicular to the first shaft 110. The lower arm 116 rotates about the second shaft 114. In other words, the rotation direction of the second shaft 114 is the direction in which the angle formed between the lower arm 116 and the first shaft 110 changes. The third shaft 118 is supported parallel to the second shaft 114 by a tip 129, which is the end of the lower arm 116 opposite to the second shaft 114.

[0017] The upper arm 120 has a connecting arm 130, a fourth shaft 134, and a holding arm 132, and rotates as a whole about the third shaft 118 and the fourth shaft 134. The connecting arm 130 is rotatably connected to the lower arm 116 via the third shaft 118. The holding arm 132 is rotatably connected to the connecting arm 130 via the fourth shaft 134 extending in the longitudinal direction of the holding arm 132, so as to twist around the fourth shaft 134.

[0018] A wrist unit 136 is connected to the tip end of the holding arm 132. The wrist unit 136 rotates in a tilting direction rather than a twisting direction relative to the holding arm 132 via a fifth axis (wrist axis) 138. A first hand 142 and a second hand 146, which are end effectors on which a workpiece is placed, are attached to the wrist unit 136. In this way, the vertical articulated robot 100 employs a so-called double hand.

[0019] The first hand 142 rotates via a sixth axis (first hand axis) 140 in a direction (twisting direction) perpendicular to the rotation direction of the wrist unit 136. The second hand 146 rotates via a seventh axis (second hand axis) 144 coaxial with the sixth axis 140 in a direction perpendicular to the rotation direction of the wrist unit 136. The fifth axis 138, the sixth axis 140, and the seventh axis 144 are supported by the wrist unit 136 in a direction perpendicular to the fourth axis 134.

[0020] In this way, the vertical articulated robot 100 has the first axis 110 arranged horizontally, and the swivel frame 112 rotates in a direction approximately perpendicular to the installation surface 109. This allows the second axis 114 and subsequent axes and arms to perform circular motion in a direction approximately perpendicular to the installation surface 109 using the first axis 110.

[0021] Fig. 2 is a partial cross-sectional view illustrating a main portion of the holding arm (first arm) 132 in Fig. 1. Fig. 3 is a partial cross-sectional view showing an enlarged portion of the holding arm (first arm) 132 in Fig. 2. The figure shows the internal structure of the holding arm 132 and wrist unit 136 of the vertical articulated robot 100.

[0022] 2, the vertical articulated robot 100 includes a fifth axis motor (wrist axis motor) 148, a sixth axis motor (first hand axis motor) 150, and a seventh axis motor (second hand axis motor) 152 within the holding arm 132. The fifth axis motor 148, the sixth axis motor 150, and the seventh axis motor 152 have motor shafts 148a, 150a, and 152a, respectively, and are the drive sources for the fifth axis 138, the sixth axis 140, and the seventh axis 144.

[0023] These three motors, namely, fifth axis motor 148, sixth axis motor 150, and seventh axis motor 152, are housed in holding arm 132 as shown in the figure. Furthermore, the three motors, including motor shafts 148a, 150a, and 152a, are generally arranged in parallel with each other.

[0024] The driving force of the fifth axis motor 148 is transmitted to the fifth axis 138 via a timing belt 154. The timing belt 154 is arranged to span between a motor shaft 148a of the fifth axis motor 148 and the fifth axis 138 that rotates the wrist unit 136. This allows the fifth axis 138 to rotate by driving the fifth axis motor 148.

[0025] As described above, the fifth axis 138 rotates by driving the fifth axis motor 148, and transmits driving force to the wrist unit 136 while being further decelerated via the wave reducer 170. As a result, the wrist unit 136 rotates relative to the holding arm 132 while being decelerated via the fifth axis 138 and the wave reducer 170. Note that in Figures 2 and 3, the members that move together with the fifth axis 138 are hatched.

[0026] 3, the wave reducer 170 has a bearing 172, a flexspline (external gear) 174, and a circular spline (internal gear) 176. In the wave reducer 170, the outer circular spline 176 is fixed, and the flexspline 174, which is arranged inside the circular spline 176, rotates as the wrist unit 136.

[0027] The driving force of the sixth-axis motor 150 is transmitted to the first intermediate shaft 160 via a timing belt 156. The first intermediate shaft 160 is disposed coaxially with the fifth shaft 138. The timing belt 156 is disposed so as to span between the motor shaft 150a of the sixth-axis motor 150 and the first intermediate shaft 160.

[0028] The first gear 162a is a bevel gear attached to the first intermediate shaft 160. The second gear 162b is a bevel gear attached coaxially to the sixth shaft 140 and meshes with the first gear 162a. Therefore, when the sixth shaft motor 150 is driven, the first gear 162a rotates together with the first intermediate shaft 160, and the second gear 162b, which meshes with the first gear 162a, rotates together with the sixth shaft 140. As a result, by driving the sixth shaft motor 150, the sixth shaft 140 can be rotated.

[0029] The sixth shaft 140 transmits driving force to the plate 168 while reducing the speed via a wave reducer 180. The first hand 142 is attached to the plate 168. This causes the first hand 142 to rotate in a direction perpendicular to the rotation direction of the wrist unit 136. Note that in Figures 2 and 3, the members that move together with the sixth shaft 140 are hatched.

[0030] 3, the wave reducer 180 has a bearing 182, a flexspline (external gear) 184, and a circular spline (internal gear) 186. In the wave reducer 180, the flexspline 184 is fixed to the wrist unit 136, and the circular spline 186, which is arranged on the outside of the flexspline 184, rotates as the sixth axis 140.

[0031] As shown in the figure, the sixth axis 140 is cylindrical, and the seventh axis 144 is coaxially arranged inside the sixth axis 140. The sixth axis 140 and the seventh axis 144 are attached to the wrist unit 136.

[0032] The driving force of the seventh-axis motor 152 is transmitted to the second intermediate shaft 164 via a timing belt 158. The second intermediate shaft 164 is disposed coaxially with the fifth shaft 138 and the first intermediate shaft 160. The timing belt 158 ​​is disposed so as to span between the motor shaft 152a of the seventh-axis motor 152 and the second intermediate shaft 164.

[0033] The third gear 166a is a bevel gear coaxially attached to the second intermediate shaft 164 and is coaxial with the first gear 162a. The fourth gear 166b is a bevel gear coaxially attached to the seventh shaft 144 and is coaxial with the second gear 162b, and further meshes with the third gear 166a.

[0034] Therefore, when the seventh shaft motor 152 is driven, the third gear 166a rotates together with the second intermediate shaft 164, and the fourth gear 166b meshing with the third gear 166a rotates together with the seventh shaft 144. As a result, by driving the seventh shaft motor 152, the seventh shaft 144 can be rotated.

[0035] The seventh shaft 144 transmits driving force to the plate 169 while reducing the speed via a wave reducer 190. The second hand 146 is attached to the plate 169. This allows the second hand 146 to rotate coaxially with the first hand 142. Note that in Figures 2 and 3, the members that move together with the seventh shaft 144 are hatched.

[0036] 3, the wave reducer 190 has a bearing 192, a flexspline (external gear) 194, and a circular spline (internal gear) 196. In the wave reducer 190, the flexspline 194 is fixed, and the circular spline 196, which is arranged on the outside of the flexspline 194, rotates as the seventh axis 144.

[0037] In this way, in the vertical articulated robot 100, three motors, that is, the fifth axis motor 148, the sixth axis motor 150, and the seventh axis motor 152, are housed in the holding arm 132 in parallel with each other.

[0038] In addition, in the wrist unit 136, a first intermediate shaft 160, a second intermediate shaft 164, a first gear 162a, and a third gear 166a are arranged coaxially with the fifth shaft 138. In addition, in the wrist unit 136, a sixth shaft 140, a seventh shaft 144, a second gear 162b, and a fourth gear 166b are arranged coaxially.

[0039] Therefore, with the vertical articulated robot 100, by arranging the components as described above, it is possible to house three motors in the holding arm (first arm) 132. Therefore, even when a double hand is adopted in which the first hand 142 and the second hand 146 are attached to the wrist unit 136, it is possible to reduce the weight and space of the wrist unit 136.

[0040] While preferred embodiments of the present invention have been described above with reference to the accompanying drawings, it goes without saying that the present invention is not limited to substrate transport applications. The present invention is a versatile vertical articulated robot that can also be used for handling and loading in narrow layouts. It is clear that those skilled in the art can conceive of various modifications and alterations within the scope of the claims, and it is understood that these also fall within the technical scope of the present invention. [Industrial Applicability]

[0041] The present invention can be used as a vertical articulated robot having double hands. [Explanation of symbols]

[0042] 100...vertical articulated robot, 108...base, 109...mounting surface, 110...first axis, 112...swivel frame, 114...second axis, 116...lower arm, 118...third axis, 120...upper arm, 122, 126, 128...side of base, 124...connector, 129...tip of lower arm, 130...connecting arm, 132...holding arm (first arm), 134...fourth axis, 136...wrist unit, 138...fifth axis (wrist axis), 140...sixth axis (first hand axis), 142...first hand, 144...seventh axis (second hand axis), 146...second hand, 148...fifth axis motor (wrist axis motor) ), 150...6th axis motor (first hand axis motor), 152...7th axis motor (second hand axis motor), 148a, 150a, 152a...motor shaft, 154, 156, 158...timing belt, 160...first intermediate shaft, 162a...first gear, 162b...second gear, 164...second intermediate shaft, 166a...third gear, 166b...fourth gear, 168, 169...plate, 170, 180, 190...wave reducer, 172, 182, 192...bearing, 174, 184, 194...flexspline (external gear), 176, 186, 196...circular spline (internal gear)

Claims

[Claim 1] A first arm; a wrist unit connected to the first arm and having a first hand and a second hand attached thereto; a wrist axis that rotates the wrist unit in a direction inclined relative to the first arm; a first hand shaft attached to the wrist unit and configured to rotate the first hand in a direction perpendicular to a rotation direction of the wrist unit; a second hand shaft attached to the wrist unit and configured to rotate the second hand coaxially with the first hand shaft; a wrist shaft motor, a first hand shaft motor, and a second hand shaft motor, which are drive sources for the wrist shaft, the first hand shaft, and the second hand shaft, and which are housed in the first arm and arranged in parallel to each other; a first intermediate shaft that is arranged coaxially with the wrist shaft and receives a driving force from the first hand shaft motor; a first gear attached to the first intermediate shaft; a second gear attached coaxially to the first hand shaft and meshing with the first gear; a second intermediate shaft that is arranged coaxially with the wrist shaft and the first intermediate shaft and receives a driving force from the second hand shaft motor; a third gear attached coaxially to the second intermediate shaft; a fourth gear attached coaxially to the second hand shaft and meshing with the third gear.

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