JP7342488B2 - Workpiece conveyance device - Google Patents

Description

The present invention relates to a workpiece conveyance device.

Conventionally, arm-type transport robots have been widely used for transporting workpieces, etc. (see, for example, Patent Document 1). This arm-type transfer robot has multiple arms, multiple joints, and a motor provided for each arm, and can freely change its posture by rotating each arm individually with each motor. It is configured to allow desired operations. Compared to orthogonal robots (also called orthogonal loaders) that move along two or more orthogonal travel rails, such transfer robots have the advantage of being smaller in size and having greater freedom of movement. be.

Japanese Patent Application Publication No. 2018-69370

However, the arm-type transfer robot has a structure in which a plurality of arms are each provided with a motor to drive each arm, which causes problems in that the structure is complicated and the cost is high. On the other hand, such transport robots have the ability to freely change their posture and perform various operations, but when used exclusively for relatively simple transport of workpieces in machine tools, , it is thought that there may be cases where the specifications are over.

SUMMARY OF THE INVENTION An object of the present invention is to provide a workpiece transport device that is small, simple, and inexpensive to transport workpieces .

One aspect of the present invention is a workpiece conveyance device installed in a machine tool that processes a workpiece,
A transfer robot including a base body and a holding part that holds a workpiece in a releasable manner;
a moving mechanism configured to move the base body along the loading/unloading position of the workpiece in the machine tool and the processing position;
A pallet device having a pallet on which the unprocessed or processed workpiece is placed, and a feeding mechanism that sends the workpiece to the loading/unloading position on the pallet,
The transport robot is
the base body;
a first arm having a first end and a second end at both ends in the longitudinal direction, the first end being connected to the base body;
a second arm having a third end and a fourth end at both ends in the longitudinal direction, the third end being connected to the second end of the first arm;
the holding part connected to the fourth end of the second arm and releasably holding the workpiece;
a motor that is attached to the base body and rotates a motor shaft,
The first arm is arranged in a position where its longitudinal direction intersects with the axial direction of the motor shaft, and the first end is fixed to the motor shaft,
The first arm further includes:
a first pulley provided at the first end coaxially with the motor shaft and fixed to the base body;
a second pulley rotatably provided at the second end;
a first belt spanning between the first pulley and the second pulley;
a first rotating shaft member coaxially fixed to the second pulley;
Equipped with
The second arm is arranged in a position where the longitudinal direction thereof intersects with the axial direction of the first rotating shaft member, and the third end is fixed to the first rotating shaft member,
The second arm further includes:
a third pulley fixed to the second end;
a fourth pulley rotatably provided at the fourth end;
a second belt spanned between the third pulley and the fourth pulley;
a second rotating shaft member coaxially fixed to the fourth pulley;
Equipped with
The holding portion is fixed to the second rotating shaft member and moves linearly as the postures of the first arm and the second arm change,
The feed mechanism is located in a workpiece transfer device that is driven by the movement of the holding section in the transfer robot.

Further, another aspect of the present invention is a workpiece conveyance device disposed above a grinding machine that is a machine tool for processing a workpiece,
A transfer robot including a base body and a holding part that holds a workpiece in a releasable manner;
a moving mechanism configured to move the base body along the loading/unloading position of the workpiece in the machine tool and the processing position,
The transport robot is
the base body;
a first arm having a first end and a second end at both ends in the longitudinal direction, the first end being connected to the base body;
a second arm having a third end and a fourth end at both ends in the longitudinal direction, the third end being connected to the second end of the first arm;
the holding part connected to the fourth end of the second arm and releasably holding the workpiece;
a motor that is attached to the base body and rotates a motor shaft,
The first arm is arranged in a position where its longitudinal direction intersects with the axial direction of the motor shaft, and the first end is fixed to the motor shaft,
The first arm further includes:
a first pulley provided at the first end coaxially with the motor shaft and fixed to the base body;
a second pulley rotatably provided at the second end;
a first belt spanning between the first pulley and the second pulley;
a first rotating shaft member coaxially fixed to the second pulley;
Equipped with
The second arm is arranged in a position where the longitudinal direction thereof intersects with the axial direction of the first rotating shaft member, and the third end is fixed to the first rotating shaft member,
The second arm further includes:
a third pulley fixed to the second end;
a fourth pulley rotatably provided at the fourth end;
a second belt spanned between the third pulley and the fourth pulley;
a second rotating shaft member coaxially fixed to the fourth pulley;
Equipped with
The holding portion is fixed to the second rotating shaft member and moves linearly as the postures of the first arm and the second arm change,
The moving mechanism is configured to move the base body in a horizontal direction above the grinding machine,
The transport robot is included in a workpiece transport device that transports the workpiece in a vertical direction between a position directly above the processing position and the processing position.

According to these configurations, when the motor rotates the motor shaft, the first arm, the first end of which is fixed to the motor shaft, pivots around the axis of the motor shaft. Since the first pulley is fixed to the base body, it does not rotate due to rotation of the motor shaft. The second pulley rotatably provided at the second end is rotated in the opposite direction to the rotation of the motor shaft by the rotational force caused by the rotation of the first arm being transmitted via the first belt. At this time, the first rotating shaft member coaxially fixed to the second pulley rotates in the same direction as the rotation of the second pulley. Accordingly, the second arm, the third end of which is fixed to the first rotating shaft member, pivots in the opposite direction to the first arm. Since the third pulley is fixed to the second end, its relative rotational position does not change. The fourth pulley, which is rotatably provided at the fourth end, receives the rotational force caused by the rotation of the second arm via the second belt, so that the fourth pulley rotates in the opposite direction to the rotation of the second pulley (i.e., the rotation of the motor shaft). rotate in the same direction). At this time, the second rotating shaft member fixed to the fourth pulley rotates in the same direction as the rotation of the fourth pulley. The holding portion fixed to the second rotation shaft member is rotated by the second rotation shaft member in the same direction as the rotation of the fourth pulley, that is, in the same direction as the rotation direction of the first arm.

That is, according to the workpiece conveyance device according to the present invention, by changing the postures of the first arm and the second arm using one motor, it is possible to linearly move the holding part in the same posture. Therefore, it is possible to convey the workpiece with a small, simple, and inexpensive structure.

As described above, the workpiece transfer device according to the present invention includes the transfer robot and a movement mechanism that moves the base body along a plurality of work positions with respect to the workpiece.

According to these configurations, the base body can be moved to a desired working position by the moving mechanism, and the postures of the first arm and the second arm can be changed by one motor, so that the holding part can be kept in the same position. You can move in a straight line depending on your posture. Therefore, it is possible to transport workpieces between a plurality of work positions with a small, simple, and inexpensive configuration.

1 is a front view showing the overall configuration of a processing system to which a workpiece conveyance device according to an embodiment is applied. FIG. 2 is a right side view showing the overall configuration of the processing system. FIG. 1 is a plan view showing the overall configuration of a processing system. FIG. 3 is an internal structure diagram showing the internal structure of the transfer robot in a front view. FIG. 3 is an exploded perspective view showing the assembly structure of the arm body of the transfer robot. FIG. 3 is an internal structure diagram showing the internal state of the transfer robot when its arm is extended in a side view. FIG. 2 is an internal structure diagram showing the internal state of the transfer robot when the arm is bent in a side view. FIG. 2 is an overall perspective view showing the appearance of the pallet device. It is an internal structure diagram showing the internal structure of the feeding mechanism of the pallet device in a side view. FIG. 3 is an operation explanatory diagram showing a state of a workpiece delivery operation on a delivery pallet. FIG. 2 is a front view of the machine tool showing a state in which the transfer robot is located at a carry-in position. FIG. 3 is a front view of the machine tool showing a state in which the transfer robot is located directly above the processing position. FIG. 2 is a front view of the machine tool showing a state in which the transport robot transports the workpiece to a processing position. FIG. 3 is a front view of the machine tool showing a state in which the transfer robot is located at a workpiece unloading position. FIG. 3 is a front view of the machine tool showing how the transfer robot presses down the operating lever of the pallet device with a hand section.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a transfer robot and a workpiece transfer device of the present invention will be described with reference to the drawings.
(1. Overall configuration of processing system 1)
The overall configuration of an embodiment of a processing system 1 to which a transfer robot and a workpiece transfer device of the present invention are applied will be described with reference to FIGS. 1 to 3. The machining system 1 includes a grinding machine 100 and a workpiece conveying device 200 that conveys the workpiece W between a carry-in position P1, a carry-out position P2, and a machining position P3 of the workpiece W in the grinding machine 100. Ru. Note that the carry-in position P1, the carry-out position P2, and the processing position P3 are located side by side in order from left to right in the X-axis direction. Further, the carry-in position P1 and the carry-out position P2 are located at a height above the grinding machine 100 in the Y-axis direction, and the processing position P3 is located above the table 121 of the grinding machine 100.

(2. Configuration of grinding machine 100)
The grinding machine 100 is a cylindrical grinding machine, and is a machine tool that performs grinding by moving a grinding wheel 111 relative to a workpiece W supported on a bed 102. The grinding machine 100 includes a grinding wheel head 110, a Z-axis feed device (not shown), a workpiece support device 120, an X-axis feed device (not shown), a control device 140, and a machine cover 103. be done.

The whetstone head 110 has a whetstone wheel 111 rotatably provided via a whetstone shaft (not shown). The grindstone head 110 is provided with a grindstone rotation drive device (not shown) that rotationally drives a grindstone wheel 111 for grinding the workpiece W.

Further, the grindstone head 110 is guided and supported on a not-illustrated guide rail that is disposed on the upper surface of the bed 102 and extends in a direction perpendicular to the central axis of the grindstone wheel 111. The grinding wheel 111 is moved in the Z-axis direction (towards the front of the paper in FIG. 1), which is parallel to the upper surface of the bed 102 and in the radial direction of the workpiece W, by a Z-axis feeding device. Furthermore, the Z-axis motor of the Z-axis feeding device and the grindstone rotation drive device are controlled by the control device 140 to control the movement of the grindstone 111 in the Z-axis direction and the rotation speed of the grindstone 111 .

The workpiece support device 120 supports both ends of the cylindrical workpiece W so as to be rotatable around the central axis of the workpiece W. The workpiece support device 120 includes a table 121, a headstock 122, and a tailstock 123. The table 121 is placed on the upper surface of the bed 102 of the grinding machine 100 and is guided and supported on a guide rail (not shown) that extends in the direction of the central axis of the grinding wheel 111 . The table 121 is moved in the X-axis direction (horizontal direction in FIG. 1) parallel to the upper surface of the bed 102 and in the axial direction of the workpiece W by an X-axis feed device (not shown) consisting of an X-axis motor and an X-axis ball screw. It is supposed to move to .

The headstock 122 and the tailstock 123 are arranged to face the upper surface of the table 121 and support one end or the other end of the workpiece W, respectively. The headstock 122 is equipped with a main shaft 127 that is rotated by a main shaft rotation drive device (not shown), and the workpiece W is configured to rotate when the main shaft 127 is rotationally driven. Further, in the spindle rotation drive device, the rotation speed, rotational phase, etc. of the spindle 127 are controlled by the control device 140. The workpiece W is rotatably supported at both ends about an axis parallel to the moving direction (X-axis direction) of the table 121, and is rotationally driven by a spindle rotation drive device.

The control device 140 is a CNC control device that can grind the workpiece W through numerical control by executing a machining program, and is configured using a computer including a CPU, ROM, RAM, hard disk, and the like. The control device 140 is connected to an X-axis feed device, a Z-axis feed device, a grindstone rotation drive device that rotationally drives a grindstone shaft, a spindle rotation drive device that rotationally drives the main shaft 127, and various sensors. , which processes signals from each sensor and controls each part. Note that the control device 140 further includes an input means for inputting a machining program, etc., and an output means (both not shown) for outputting processing contents, processing status, etc.

The control device 140 also controls the workpiece conveyance device 200. Specifically, the control device 140 is connected to a traveling motor 215, which will be described later, and controls the traveling of the base body 221. Further, the control device 140 is electrically connected to a turning motor 230, which will be described later, and controls the turning of the transfer robot 220. Further, the control device 140 is electrically connected to a hand section 260, which will be described later, to control the opening and closing of the gripping claws 261. Note that the hand portion 260 constitutes a holding portion that releasably holds a workpiece in the present invention.

The body cover 103 is made of a steel plate or the like, and covers the front, rear, left, and right sides and top surface of each of the above-mentioned parts of the grinding machine 100 . The body cover 103 includes an opening 104 for taking the workpiece W into and out of the processing position P3, and a shutter 105 for freely opening and closing the opening 104. The processing position P3 of the workpiece W is between the headstock 122 and the tailstock 123, where the workpiece W being processed is supported. The shutter 105 is provided to prevent the coolant supplied to the processing position P3 of the workpiece W from scattering around.

(3. Configuration of workpiece transfer device 200)
Next, the configuration of the workpiece transfer device 200 will be explained. As shown in FIGS. 1 and 2, the workpiece conveyance device 200 is provided above the grinding machine 100, that is, on the upper surface of the machine cover 103 that covers the entire grinding machine 100, and transports the workpiece W to a carry-in position P1 and a carry-out position P1. This is a device for transporting between position P2 and processing position P3. The workpiece transfer device 200 includes a moving mechanism 210, a transfer robot 220, and a pallet device 270. In the following description, the carry-in position P1 and the carry-out position P2 are collectively referred to as carry-in and carry-out positions P1 and P2.

(3.1 Configuration and operation of moving mechanism 210)
The moving mechanism 210 is a mechanism that moves the base body 221 of the transfer robot 220 in the X-axis direction. The moving mechanism 210 includes a pair of support columns 212, a traveling platform 213, and a traveling motor 215.

A pair of pillars 212 are erected in left and right pairs on the upper surface of the body cover 103 and extend in the vertical direction (Y-axis direction). The traveling platform 213 extends in the left-right direction (X-axis direction) between the upper ends of the pair of columns 212. Two construction rails 214 are vertically provided on the front surface of the traveling platform 213 at intervals, and extend in the left-right direction (X-axis direction).

The travel motor 215 is attached to the front surface of the base body 221 of the transfer robot 220. The travel motor 215 rotates a pinion gear 218 attached to a motor shaft 217. A rack 219 having a plurality of teeth attached to the carriage 213 meshes with a pinion gear 218 . As the traveling motor 215 rotates, the base body 221 travels along the construction rail 214 in the horizontal X-axis direction.

(3.2 Configuration and operation of transfer robot 220)
As shown in FIG. 4, the transfer robot 220 includes a base body 221, a rotation motor 230, a first arm 240, a second arm 250, and a hand section 260. As described above, the base body 221 is configured to be movable in the X-axis direction along the construction rail 214 by the moving mechanism 210. The turning motor 230 is attached to the base body 221 and rotates a motor shaft 231. The turning motor 230 is arranged with a motor shaft 231 facing the X-axis direction.

The first arm 240 has a first end 241 and a second end 242 at both longitudinal ends, and the first end 241 is connected to the base body 221 . The second arm 250 has a third end 251 and a fourth end 252 at both longitudinal ends, and the third end 251 is connected to the second end 242 of the first arm 240 . Note that in this specification, the first end 241 refers to a region including a side surface adjacent to one end surface of the first arm 240 in the longitudinal direction. The same applies to the second end 242, the third end 251, and the fourth end 252. Hereinafter, the configurations of the first arm 240 and the second arm 250 will be specifically explained with reference to FIGS. 4 to 7.

First, the structure of the arm body of the first arm 240 will be explained with reference to FIG. 5. As shown in FIG. 5, the first arm 240 includes a pair of metal plates 240a arranged facing each other in parallel at a predetermined interval, and a connecting member 240p consisting of a cylindrical pin and a bolt screwed into the inner periphery of the pin. The arm body is constructed by connecting each other at a plurality of locations using. The metal plate 240a is processed into a desired contour shape (in this embodiment, an elongated shape with rounded longitudinal ends) using a laser processing machine or the like. The metal plate 240a may have a configuration in which circular or triangular holes are formed at multiple locations to reduce the weight, as long as the strength can be ensured. According to the structure of the first arm 240 formed by connecting a pair of metal plates 240a with a connecting member 240p in this embodiment, the internal mechanism can be observed easily compared to a conventional structure formed into a shell shape by casting, welding, etc. It has the advantage of being easy to maintain, and when used in an environment where there is no problem even if it gets dusty, or when the belt breaks, etc., the component parts are easy to maintain. The second arm 250 has the same length and shape as the first arm 240, and the structure of the arm body is the same as the first arm 240, so a detailed description thereof will be omitted.

Next, the internal structures of the first arm 240 and the second arm 250 will be described with reference to FIGS. 4, 6, and 7. The first arm 240 is arranged such that its longitudinal direction is perpendicular to the axial direction of the motor shaft 231, and the first end 241 is fixed to the motor shaft 231. The first arm 240 includes a first pulley 243 provided coaxially with the motor shaft 231 at a first end 241 and fixed to the base body 221, and a second pulley 244 rotatably provided at a second end 242. ing. The first arm 240 further includes a first belt 245 that is stretched between the first pulley 243 and the second pulley 244, and a first rotating shaft member 246 that is coaxially fixed to the second pulley 244. . The ratio of the number of teeth between the first pulley 243 and the second pulley 244 is 2:1. Therefore, the rotation ratio between the first pulley 243 and the second pulley 244 is 1:2.

The second arm 250 is arranged such that its longitudinal direction is perpendicular to the axial direction of the first rotating shaft member 246, and the third end 251 is fixed to the first rotating shaft member 246. The second arm 250 includes a third pulley 253 fixed to the second end 242 and a fourth pulley 254 rotatably provided to the fourth end 252. The second arm 250 further includes a second belt 255 that is stretched between the third pulley 253 and the fourth pulley 254, and a second rotating shaft member 256 that is coaxially fixed to the fourth pulley. The ratio of the number of teeth between the third pulley 253 and the fourth pulley 254 is 1:2. Therefore, the rotation ratio between the third pulley 253 and the fourth pulley 254 is 2:1. That is, the rotation ratio of the first pulley 243, the second pulley 244, the third pulley 253, and the fourth pulley 254 is 1:2:1.

Next, the configuration of the hand section 260 will be explained. The hand portion 260 is a member that releasably grips the workpiece W, and is fixed to the second rotating shaft member 256 via a bracket 258. The hand section 260 is a known device called an air chuck, and includes a pair of gripping claws 261 that can be opened and closed, and an air cylinder 262. In the hand section 260, a pair of gripping claws 261 are driven to open and close by an air cylinder 262 based on a command signal from the control device 140, and the hand section 260 has an open state in which the workpiece W is released and a closed state in which the workpiece W is gripped. You can switch with .

Next, the operation of each part of the transfer robot 220 will be explained. When the turning motor 230 is driven by a command from the control device 140 and rotates the motor shaft 231 in the direction of arrow A (clockwise in FIG. 7), the first arm whose side surface of the first end 241 is fixed to the motor shaft 231 240 rotates around the motor shaft 231 in the direction of arrow B (clockwise in FIG. 7). At this time, since the first pulley 243 is fixed to the base body 221, it does not rotate due to the rotation of the motor shaft 231.

The second pulley 244 rotatably provided at the second end 242 receives the rotational force caused by the rotation of the first arm 240 via the first belt 245 and is rotated in the direction indicated by arrow C opposite to the rotation of the motor shaft 231. Rotate in the direction. At this time, the first rotating shaft member 246 coaxially fixed to the second pulley 244 rotates in the same direction as the second pulley 244 rotates.

Accordingly, the second arm 250 whose third end 251 side surface is fixed to the first rotating shaft member 246 pivots around the first rotating shaft member 246 in the direction of arrow D opposite to the first arm 240. . Since the third pulley 253 is fixed to the second end 242, the relative rotational position with respect to the second end 242 does not change. Here, since the rotation ratio of the first pulley 243, second pulley 244, and third pulley 253 is 1:2, the second arm 250 turns at twice the angle in the opposite direction to the first arm 240. I will do it.

The fourth pulley 254 rotatably provided at the fourth end 252 receives the rotational force caused by the rotation of the second arm 250 via the second belt 255, and rotates in the direction indicated by the arrow E opposite to the rotation of the second pulley 244. direction (that is, the same direction as the rotation of the motor shaft 231). At this time, the second rotating shaft member 256 coaxially fixed to the fourth pulley 254 rotates in the same direction as the fourth pulley 254 rotates. Since the rotation ratio of the first pulley 243, the second pulley 244, the third pulley 253, and the fourth pulley 254 is 1:2:1, the hand portion is fixed to the second rotating shaft member 256 via the bracket 258. 260 is rotated by the second rotation shaft member 256 in the same direction as the rotation of the fourth pulley 254, that is, in the same direction as the rotation direction of the first arm 240, by the same angle.

In other words, in the transfer robot 220, the first and second arms 240, 250 change their postures using the single rotation motor 230, thereby making it possible to linearly move the hand section 260 in the vertical direction in the same posture.

(3.3 Configuration and operation of pallet device 270)
Next, the configuration of the pallet device 270 will be explained with reference mainly to FIGS. 8 to 10. The pallet device 270 includes a carry-in pallet 270a, a carry-out pallet 270b, and a feed mechanism 280 having an operation lever 281. The carrying-in pallet 270a has a plurality of V-shaped placing parts on which bar-shaped workpieces W can be placed one by one along the feeding direction, and has a plurality of V-shaped placing parts on which a plurality of unprocessed workpieces W can be placed and is also used for carrying-in. This is a mechanism for sequentially sending out one piece at a time toward position P1.

Specifically, the carry-in pallet 270a has a mounting table 271a and a feeding table 272a. The mounting table 271a has a pair of plate-like members provided on both sides in the width direction, and has a plurality of V-shaped bevels formed at the same pitch in the longitudinal direction. The feed table 272a has a pair of plate-like members disposed inside the mounting table 271a in the width direction with a gap between them, and has a plurality of chevron-shaped bevels formed at the same pitch as the bevels of the mounting table 271a. The mounting table 271a is a fixed member and does not operate. On the other hand, the feed table 272a is a movable member, and is connected to a rotating shaft member 273a, and is configured to pivot vertically and forwardly by rotation of the rotating shaft member 273a.

The carry-out pallet 270b is arranged side by side in the X-axis direction so that the feeding direction is opposite to that of the carry-in pallet 270a, and is a mechanism that can sequentially send out processed workpieces W one by one from the carry-out position P2. Since the carry-out pallet 270b has the same configuration as the carry-in pallet 270a, detailed explanation will be omitted. Note that the mounting table 271b corresponds to the mounting table 271a, the feeding table 272b corresponds to the feeding table 272a, and the rotating shaft member 273b corresponds to the rotating shaft member 273a.

The feed mechanism 280 is a mechanism that rotates an input-side rotation shaft member 273a provided on the input pallet 270a and an output-side rotation shaft member 273b provided on the output pallet 270b by pressing down the operation lever 281. The feeding mechanism 280 includes an operating lever 281 that forms a head, a rack 282 that extends below the operating lever 281 and has a plurality of teeth, and a housing 283 that accommodates the lower part of the rack 282 in a vertically movable manner. The rack 282 includes a spring 284 interposed between the operating lever 281 and the housing 283. Inserted into the housing 283 are an end of a rotating shaft member 273a on the carry-in side to which a pinion gear 274a is fixed, and an end of a rotating shaft member 273b on the carry-out side to which a pinion gear 274b is fixed. . The pinion gear 274a is arranged adjacent to the rack 282, and a plurality of teeth formed on the outer periphery of the pinion gear 274a mesh with a plurality of teeth of the rack 282. The pinion gear 274b is disposed on the opposite side of the rack 282 with the pinion gear 274a in between, and some of the teeth formed on the outer periphery of the pinion gear 274b are part of the teeth of the pinion gear 274a. They mesh together.

Next, the operation of each part of the pallet device 270 will be explained. When the transfer robot 220 extends the first and second arms 240 and 250 directly above the operating lever 281 and the hand section 260 descends and the operating lever 281 is pressed down, the robot resists the urging force of the spring 284. Then, the rack 282 slides downward. As the rack 282 slides downward, the pinion gear 274a that meshes with the rack 282 rotates counterclockwise as shown by the arrow in FIG. As a result, the rotation shaft member 273a on the loading side fixed to the pinion gear 274a rotates, and the feed table 272a performs an arc movement up and down and back and forth, so that the feed table 272a is placed in each V-shaped groove of the mounting table 271a. Unprocessed workpieces W are sent one by one in the direction indicated by the arrow in FIG. 8 toward the carry-in position P1.

At the same time, pinion gear 274b, which meshes with pinion gear 274a, is driven by the rotation of pinion gear 274a and rotates clockwise as shown by the arrow in FIG. As a result, the rotating shaft member 273b on the unloading side fixed to the pinion gear 274b rotates, and the feed table 272b performs an arc movement up and down and back and forth, so that the processed product placed in the valley of the bevel of the mounting table 271b is rotated. The workpieces W are sent one by one in the direction shown by the arrow in FIG. 8 toward the carry-out position P2. Here, FIG. 10 shows that in the carry-out pallet 270b, the feed table 272b performs circular arc movement up and down and back and forth due to the rotation of the rotation shaft member 273b on the carry-out side, so that the processing that is placed in the valley of the bevel of the mounting table 271b is carried out. It shows how the finished workpieces W are being sent one by one toward the unloading position P2. In FIG. 10, the original position of the feed base 272b before turning is shown by a two-dot chain line, and the position at the turning end is shown by a solid line. Further, point a indicates the center of the workpiece W at the original position before the feed base 272b rotates, and point b indicates the center of the workpiece W at the end of the rotation. At the turning end of the feed table 272b, the workpiece W is supported by the bevel trough of the feed table 272b and is stopped without rolling. When the transfer robot 220 releases the depression of the operating lever 281, the operating lever 281 returns to its original position by the spring 284, and the feed platform 272b also returns to its original position. The workpiece W, which had stopped rolling at point b, rolls on the S slope of the mounting table 271b and stops at point c. In this way, the workpiece W moves by one pitch on the bevel of the mounting table 271b from point a to point b and then to point c.

(4. Flow of conveyance of workpiece W in processing system 1)
Next, an example of the flow of transporting the workpiece W in the processing system 1 will be described with reference to FIGS. 11 to 15. In the initial state, an unprocessed workpiece W is placed in advance on the carry-in pallet 270a by the operator through a window (not shown) on the front side of the processing system 1. Further, it is assumed that the transport robot 220 is waiting at the initial position shown in FIG.

First, when the transport robot 220 is located at the initial position (carry-in position P1) at the left end in FIG. 1, the shutter 105 closes the opening 104 on the upper surface of the body cover 103. The first and second arms 240 and 250 were extended by driving the turning motor 230 to lower the hand section 260 directly below, and the unprocessed workpiece W was grasped by opening and closing the grasping claws 261 using the air cylinder 262. After that, the first and second arms 240 and 250 are bent and raised directly upward to return to the original height (see FIG. 11).

Next, the transfer robot 220 is moved to the right in the X-axis direction by the moving mechanism 210 to a position directly above the processing position P3. At this time, since the shutter 105 fixed to the base body 221 also moves integrally toward the right side in the X-axis direction, the opening 104 of the body cover 103 is opened (see FIG. 12).

Next, the first and second arms 240 and 250 are extended by driving the swing motor 230, and the hand section 260 is vertically lowered directly downward through the opening 104 to transport the workpiece W to the processing position P3 ( (See Figure 13). After the workpiece W is supported by the headstock 122 and tailstock 123, the gripping claws 261 are released by the air cylinder 262, and the first and second arms 240 and 250 are bent by driving the rotation motor 230. After the transport robot 220 is raised directly upward and returned to its original height, the transport robot 220 is moved to the left in the X-axis direction by the moving mechanism 210 to the initial position. At this time, since the shutter 105 fixed to the base body 221 also moves integrally toward the left in the X-axis direction, the opening 104 of the body cover 103 is closed (see FIG. 1). In this manner, with the opening 104 of the machine cover 103 closed by the shutter 105, the workpiece W is processed by the grinding machine 100.

When the grinding machine 100 finishes machining the workpiece W, the transfer robot 220 is moved to the right in the X-axis direction by the moving mechanism 210 to just above the machining position P3. Next, the rotation motor 230 is driven to extend the first and second arms 240 and 250, and the hand section 260 is lowered to the processing position P3 through the opening 104 opened by the movement of the shutter 105. The gripping claw 261 of the hand portion 260 is closed to grip the machined workpiece W, and the first and second arms 240 and 250 are bent and raised directly upward to return to the original height, and then moved. The mechanism 210 moves the transfer robot 220 to the left in the X-axis direction to a position directly above the carry-out position P2 (FIG. 14).

Next, the gripping claws 261 are closed by the air cylinder 262 of the hand section 260 to grip the machined workpiece W, and the first and second arms 240 and 250 are extended by the drive of the turning motor 230, and the hand section 260 is lowered to the carry-out position P2, and the gripping claws 261 are released to place the pallet 260 on the carry-out pallet 270b.

Next, the gripping claw 261 is closed, the first and second arms 240 and 250 are bent by driving the rotation motor 230, and the hand part 260 is raised, and then the transfer robot 220 is moved in the X-axis direction by the moving mechanism 210. Move it toward the left until it is directly above the operating lever 281. Then, the rotation motor 230 is driven to extend the first and second arms 240 and 250, and the operating lever 281 is pushed down by the lower surface of the grip claw 261 of the hand section 260. As a result, the processed workpieces W placed on the carry-out pallet 270b are sent one by one from the carry-out position P2 side, and at the same time, the unprocessed workpieces W placed on the carry-in pallet 270a are carried in one by one. It is sent to the position P1 side.

Next, the rotation motor 230 is driven to bend the first and second arms 240 and 250 to raise the hand section 260, and then the transfer robot 220 is moved toward the left side in the X-axis direction by the moving mechanism 210 to a carry-in position P1. Return to the initial position directly above. Thereafter, by repeating the above-described operations, the processing system 1 can perform a series of processes from carrying in the unprocessed workpiece W, processing it with the grinder 100, and carrying out the processed workpiece W.

(5. Summary)
As described above, according to the transfer robot 220 according to the present embodiment, the first and second arms 240 and 250 change their postures using one turning motor 230, thereby causing the hand unit 260 to move linearly. I can do it. Therefore, it is possible to convey the workpiece W with a small, simple, and inexpensive configuration.

Further, in the transfer robot 220, the first arm 240 and the second arm 250 have the same distance L between their shafts. According to this configuration, the hand section 260 can be vertically linearly moved directly below the first end 241 of the first arm 240. Further, the rotation ratio between the first pulley 243 and the second pulley 244 is 1:2, and the rotation ratio between the third pulley 253 and the fourth pulley 254 is 2:1. According to this configuration, when the first arm 240 pivots in a predetermined direction by a predetermined angle, the second arm 250 pivots in the opposite direction at twice the angle, and the hand portion 260 rotates in the same direction as the first arm 240. Since the hand section 260 rotates at an angle, the hand section 260 can be moved vertically and linearly in the same posture.

In addition, the arm body of the first arm 240 is configured by arranging a pair of metal plates 240a facing each other in parallel at a predetermined interval and connecting them to each other at a plurality of locations using connecting members 240p. The second arm 250 also has a similar configuration. Therefore, compared to conventional arm-type robots in which the arm body is formed into a shell shape by casting or welding, it is easier to observe the internal mechanism, and it is easier to maintain components including consumable parts such as belts. ing.

Further, the workpiece transfer device 200 according to the present embodiment includes a transfer robot 220 and a movement mechanism 210 that moves the base body 221 along a plurality of work positions with respect to the workpiece W.

According to this configuration, the base body 221 of the transfer robot 220 can be moved to a desired working position by the moving mechanism 210, and the first and second arms 240, 250 can be adjusted By changing, the hand section 260 can be moved linearly. Therefore, the workpiece W can be transported between a plurality of work positions with a small, simple, and inexpensive configuration.

Further, the workpiece transfer device 200 is installed in the grinding machine 100 as a machine tool that processes the workpiece W, and the moving mechanism 210 moves the base body 221 to the loading/unloading position P1 of the workpiece W in the grinding machine 100. It is configured to move in the X-axis direction corresponding to P2 and processing position P3. In other words, the workpiece transport device 200 can transport the workpiece W in the horizontal direction (X-axis direction) using the moving mechanism 210, and can further transport the workpiece W in the vertical direction (Y-axis direction) using the transport robot 220. .

Further, the grinding machine 100 includes a body cover 103 that covers the surrounding area, and the body cover 103 includes an opening 104 for taking the workpiece W into and out of the processing position P3, and a shutter 105 that freely opens and closes the opening 104. ing. The shutter 105 is connected to the base body 221 and is opened and closed as the base body 221 moves in the X-axis direction. Therefore, there is no need to separately provide a cylinder device, a position sensor, etc. as a drive source for the shutter 105, and it is possible to simplify the configuration and reduce costs.

Further, the workpiece conveyance device 200 includes a pallet device 270 that includes a carry-in pallet 270a, a carry-out pallet 270b, and a sending mechanism 280 that carries the workpiece W on the carry-in and carry-out pallets 270a and 270b to the carry-in and carry-out positions P1 and P2. It is equipped with The feed mechanism 280 is driven by the operation of the hand section 260 in the transfer robot 220. Therefore, there is no need to separately provide a drive source for the feeding mechanism 280, and the configuration can be simplified and costs can be reduced.

(6. Modified example)
The present invention is not limited to the embodiments described above, and various changes can be made without departing from the spirit of the present invention. For example, in the above embodiment, an example of a processing system is shown in which the workpiece conveyance device 200 of the present invention is installed in the grinding machine 100, but the present invention is not limited to this. The workpiece conveyance device 200 of the present invention can be applied to various machine tools other than grinders. Further, in the above embodiment, an example was shown in which the transfer robot 220 is combined with the moving mechanism 210 to form a workpiece transfer device, but the transfer robot 220 may be used alone depending on the application.

In the embodiment described above, an example was shown in which the transfer robot 220 is placed facing downward and the workpiece W is transferred in the vertical direction (Y-axis direction), but the robot 220 is not limited to this and may be placed in any direction. For example, the transfer robot 220 may be arranged sideways and the workpiece W may be transferred in the horizontal direction (X-axis direction in the case of left-right arrangement, Z-axis direction in the case of front-back arrangement).

Furthermore, in the embodiment described above, the configuration for moving the base body 221 in the X-axis direction in the moving mechanism 210 is not limited to the above-described configuration using the traveling motor 215, the pinion gear 218, and the rack 219; 221 may be moved linearly in the X-axis direction by a ball screw mechanism.

Further, in the embodiment described above, an example was shown in which the rotation ratio of the first pulley 243 and the second pulley 244 was set to 1:2, and the rotation ratio of the third pulley 253 and the fourth pulley 254 was set to 2:1. , but not limited to this. When the rotation ratio between the first pulley 243 and the second pulley 244 is m:n, the rotation ratio between the third pulley 253 and the fourth pulley 254 may be set to be n:m.

Furthermore, in the embodiment described above, an example was shown in which the first arm 240 is arranged in a posture in which its longitudinal direction and the axial direction of the motor shaft 231 are orthogonal; Just place it in the position. Similarly, although an example has been shown in which the second arm 250 is arranged in a position where its longitudinal direction and the axial direction of the first rotating shaft member 246 are orthogonal, the longitudinal direction and the axial direction of the first rotating shaft member 246 are All you have to do is place it in the position you want.

Further, in the embodiment described above, an example was shown in which the hand portion 260 that releasably grips the workpiece W is connected to the fourth end 252 of the second arm 250, but the present invention is not limited to this. Instead of the hand part 260, a holding part that releasably holds the workpiece W may be provided with a suction part that attracts the workpiece W with magnetic force or air, a hook part that locks the workpiece, or the like.

Furthermore, in the embodiment described above, the second pulley 244, the first rotating shaft member 246, and the third pulley 253 are provided and fixed separately, but the present invention is not limited to this. For example, the second pulley 244 and the first rotating shaft member 246, or the first rotating shaft member 246 and the third pulley 253 may be integrated, or one pulley may rotate the second pulley 244 and the first rotating shaft member 246. It may also be configured to serve as the shaft member 246 and the third pulley 253.

W...workpiece, P1...carry-in position, P2...carry-out position, P3...processing position, 1...processing system, 100...grinding machine (machine tool), 103...body cover, 104...opening, 105...shutter, 200...work Object conveyance device, 210... Moving mechanism, 220... Transfer robot, 221... Base body, 230... Turning motor (motor), 231... Motor shaft, 240... First arm, 241... First end, 242... Second end , 243...first pulley, 244...second pulley, 245...first belt, 246...first rotating shaft member, 250...second arm, 251...third end, 252...fourth end, 253...third pulley , 254... Fourth pulley, 255... Second belt, 256... Second rotating shaft member, 260... Hand part (holding part), 270... Pallet device, 270a... Carrying in pallet (pallet), 270b... Carrying out pallet (pallet) , 280... feed mechanism.

Claims (9)

A workpiece conveyance device installed for a machine tool that processes a workpiece,
A transfer robot including a base body and a holding part that holds a workpiece in a releasable manner;
a moving mechanism configured to move the base body along the loading/unloading position of the workpiece in the machine tool and the processing position;
A pallet device having a pallet on which the unprocessed or processed workpiece is placed, and a feeding mechanism that sends the workpiece to the loading/unloading position on the pallet,
The transport robot is
the base body;
a first arm having a first end and a second end at both ends in the longitudinal direction, the first end being connected to the base body;
a second arm having a third end and a fourth end at both ends in the longitudinal direction, the third end being connected to the second end of the first arm;
the holding part connected to the fourth end of the second arm and releasably holding the workpiece ;
a motor that is attached to the base body and rotates a motor shaft,
The first arm is arranged in a position where its longitudinal direction intersects with the axial direction of the motor shaft, and the first end is fixed to the motor shaft,
The first arm further includes:
a first pulley provided at the first end coaxially with the motor shaft and fixed to the base body;
a second pulley rotatably provided at the second end;
a first belt spanning between the first pulley and the second pulley;
a first rotating shaft member coaxially fixed to the second pulley;
Equipped with
The second arm is arranged in a position where the longitudinal direction thereof intersects with the axial direction of the first rotating shaft member, and the third end is fixed to the first rotating shaft member,
The second arm further includes:
a third pulley fixed to the second end;
a fourth pulley rotatably provided at the fourth end;
a second belt spanned between the third pulley and the fourth pulley;
a second rotating shaft member coaxially fixed to the fourth pulley;
Equipped with
The holding portion is fixed to the second rotating shaft member and moves linearly as the postures of the first arm and the second arm change ,
A workpiece transfer device, wherein the feed mechanism is driven by the operation of the holding section in the transfer robot. A workpiece conveyance device placed above a grinder, which is a machine tool that processes workpieces,
A transfer robot including a base body and a holding part that holds a workpiece in a releasable manner;
a moving mechanism configured to move the base body along the loading/unloading position of the workpiece in the machine tool and the processing position,
The transport robot is
the base body;
a first arm having a first end and a second end at both ends in the longitudinal direction, the first end being connected to the base body;
a second arm having a third end and a fourth end at both ends in the longitudinal direction, the third end being connected to the second end of the first arm;
the holding part connected to the fourth end of the second arm and releasably holding the workpiece ;
a motor that is attached to the base body and rotates a motor shaft,
The first arm is arranged in a position where its longitudinal direction intersects with the axial direction of the motor shaft, and the first end is fixed to the motor shaft,
The first arm further includes:
a first pulley provided at the first end coaxially with the motor shaft and fixed to the base body;
a second pulley rotatably provided at the second end;
a first belt spanning between the first pulley and the second pulley;
a first rotating shaft member coaxially fixed to the second pulley;
Equipped with
The second arm is arranged in a position where the longitudinal direction thereof intersects with the axial direction of the first rotating shaft member, and the third end is fixed to the first rotating shaft member,
The second arm further includes:
a third pulley fixed to the second end;
a fourth pulley rotatably provided at the fourth end;
a second belt spanned between the third pulley and the fourth pulley;
a second rotating shaft member coaxially fixed to the fourth pulley;
Equipped with
The holding portion is fixed to the second rotating shaft member and moves linearly as the postures of the first arm and the second arm change ,
The moving mechanism is configured to move the base body in a horizontal direction above the grinding machine,
The transport robot is a workpiece transport device that transports the workpiece in a vertical direction between a position directly above the processing position and the processing position. According to claim 1 or 2, when the rotation ratio of the first pulley and the second pulley is m:n, the rotation ratio of the third pulley and the fourth pulley is n:m . Workpiece conveyance device. The workpiece conveyance device according to claim 3 , wherein the m is 1 and the n is 2. The workpiece conveyance device according to any one of claims 1 to 4 , wherein the first arm and the second arm have the same distance between shaft supports. The first arm is arranged in a posture in which the longitudinal direction thereof and the axial direction of the motor shaft are perpendicular to each other,
The workpiece conveyance device according to any one of claims 1 to 5 , wherein the second arm is arranged in a posture in which a longitudinal direction of the second arm and an axial direction of the first rotating shaft member are perpendicular to each other. An arm main body of each of the first arm and the second arm is configured by arranging a pair of metal plates facing each other in parallel at a predetermined interval and connecting them to each other at a plurality of locations using a connecting member. 7. The workpiece conveyance device according to any one of 1 to 6 . The machine tool includes a body cover that covers the surroundings,
The machine cover includes an opening for taking the workpiece in and out of the processing position, and a shutter that freely opens and closes the opening.
Equipped with
The workpiece conveyance device according to any one of claims 1 to 7, wherein the shutter is connected to the base body and is opened and closed as the base body moves. The machine tool is a grinding machine,
The workpiece conveyance device is arranged above the grinding machine,
The moving mechanism is configured to move the base body in a horizontal direction above the grinding machine,
The workpiece transport device according to claim 1 , wherein the transport robot transports the workpiece in a vertical direction between a position directly above the processing position and the processing position.

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