Workpiece recovery device and bucket

Abstract

A workpiece recovery device comprises: a device body (420) having a workpiece conveyance mechanism (410); a bucket (460) detachably attached to the device body (420) and having a bucket body (470) that has a first opening (491) and accommodates a workpiece conveyed by the workpiece conveyance mechanism (410), and having a first lid body (480) that is attached to the bucket body (470) and is capable of operating between a closed state (480A) in which the first opening (491) is closed and an open state (480B) in which the first opening (491) is opened; and a sensor (441) that is attached to the device body (420) and / or the first lid body (480), is capable of sensing the open / closed state of the first lid body (480), and is capable of sensing the attachment state of the bucket (460) to the device body (420).

Description

Work recovery device and bucket

[0001] This invention relates to a work recovery device and a bucket.

[0002] For example, Japanese Patent Application Laid-Open No. 2022-65319 (Patent Document 1) discloses a machine tool equipped with a work bucket for automatically recovering a work after processing from a work spindle.

[0003] Japanese Patent Application Laid-Open No. 2022-65319

[0004] As disclosed in the above Patent Document 1, a work recovery device for automatically recovering a work processed by a machine tool is known. In such a work recovery device, when recovering a work from a machine tool into a bucket, it is necessary to sense various abnormal states of the bucket. However, if the structure for sensing is complex, the work recovery device cannot be realized with a simple configuration.

[0005] An object of this invention is to provide a work recovery device and a bucket having a simple configuration.

[0006] The work recovery device according to this invention includes a device body having a work transfer mechanism, a bucket body having a first opening for accommodating a work transferred by the work transfer mechanism, a first lid attached to the bucket body and operable between a closed state closing the first opening and an open state opening the first opening, a bucket detachably attached to the device body, and a sensor attached to at least one of the device body and the first lid, capable of sensing the open / closed state of the first lid and the attachment state of the bucket to the device body.

[0007] The bucket according to this invention is a bucket for collecting workpieces transported by a workpiece transport mechanism, which is detachably attached to the main body of a device having a workpiece transport mechanism. The bucket has a first opening that opens upward, a second opening that opens horizontally and forms a transport path for workpieces from the workpiece transport mechanism, and a third opening that opens horizontally and is connected to the upper edge of the opening surface formed by the second opening, and comprises a bucket body for accommodating workpieces, a first lid that is rotatably attached to the bucket body and is capable of operating between a closed state that closes the first opening and an open state that opens the first opening, a second lid that is detachably attached to the bucket body and closes the second opening when attached to the bucket body, and a sensor that is attached to the first lid and faces the opening surface formed by the third opening when the first lid is in the closed state, and moves away from the opening surface formed by the third opening when the first lid is in the open state.

[0008] According to this invention, a workpiece recovery device and bucket with a simple configuration can be provided.

[0009] Figure 1 is a perspective view showing a machine tool equipped with a workpiece transfer device and a workpiece retrieval device. Figure 2 is another perspective view showing a machine tool equipped with a workpiece transfer device and a workpiece retrieval device. Figure 3 is a perspective view showing the tool post and the tool post movement mechanism of the machine tool in Figure 1. Figure 4 is a diagram showing the internal structure of the machine tool (closed state of the workpiece transfer device lid) as seen in the direction of the pivot axis of the tool post. Figure 5 is a diagram showing a partially enlarged view of the internal structure of the machine tool (open state of the workpiece transfer device lid) in Figure 5. Figure 6 is a diagram showing the operation of the workpiece transfer mechanism. Figure 6 is another diagram showing the operation of the workpiece transfer mechanism. Figure 6 is yet another diagram showing the operation of the workpiece transfer mechanism. Figure 6 is a diagram showing the workpiece transfer mechanism (arm in the raised position) in the area enclosed by the dashed line X in Figure 8. Figure 9 is a diagram showing the workpiece transfer mechanism (arm in the lowered position) in the area enclosed by the dashed line XI in Figure 9. Figure 4 is a top view showing the transmission mechanism (when the timing belt is functioning normally). Figure 5 is a top view showing the transmission mechanism (when the timing belt is functioning abnormally). This is a perspective view showing the cover and door of the workpiece transfer device. This is a perspective view showing the door as seen in the direction indicated by arrow XV in Figure 14. This is a perspective view showing the door as seen in the direction indicated by arrow XVI in Figure 14. This is a front view showing the machine tool in Figure 2. This is a cross-sectional view showing the machine tool along the line XVIII-XVIII in Figure 17. This is a partially enlarged view showing the internal structure of the machine tool in Figure 4 (closed state of the workpiece transfer device cover). This is a perspective view showing the door opening / closing drive mechanism and the door open state detection mechanism. This is a cross-sectional view showing the door opening / closing drive mechanism (closed state of the door) in Figure 20. This is a cross-sectional view showing the door opening / closing drive mechanism (open state of the door) in Figure 20. This is a cross-sectional view showing the door open state detection mechanism (closed state of the door) in Figure 20. This is a perspective view showing the external appearance of the machine tool in Figure 1 (with the workpiece recovery device bucket attached). This is a perspective view showing the external appearance of the machine tool in Figure 1 (with the workpiece recovery device bucket removed). This is a cross-sectional view showing the workpiece recovery device (closed state of the first cover of the bucket) in Figure 25. This is a cross-sectional view of the workpiece recovery device in Figure 25 (with the first lid of the bucket open). This is a perspective view of the bucket (with the first lid closed) as seen from the front.This is a perspective view of the bucket from the rear (with the first lid closed and the second lid removed). This is a perspective view of the bucket from the rear (with the first lid open and the second lid removed). This is a perspective view of the bucket from the rear (with the first lid closed and the second lid attached). This is a cross-sectional view of the workpiece recovery device within the area enclosed by the dashed line XXXIII in Figure 27. This is a cross-sectional view of the workpiece recovery device within the area enclosed by the dashed line XXXIV in Figure 28.

[0010] Embodiments of this invention will be described with reference to the drawings. In the drawings referred to below, the same or equivalent components are given the same numbers.

[0011] [Overall Structure of the Machine Tool] Figures 1 and 2 are perspective views showing a machine tool equipped with a workpiece transport device and a workpiece retrieval device. In Figure 2, the internal structure of the machine tool 100 is shown by not illustrating the front cover 15, control panel 16, and front door 13, which will be described later. Figure 3 is a perspective view showing the tool post and the tool post movement mechanism of the machine tool in Figure 1.

[0012] Referring to Figures 1 to 3, machine tool 100 is a lathe that performs workpiece machining by bringing a tool into contact with a rotating workpiece. Machine tool 100 is an NC (Numerically Controlled) machine tool in which various operations for workpiece machining are automated by computer numerical control.

[0013] First, the structure of the machine tool 100 will be described. The machine tool 100 has a bed (not shown), a first work spindle (not shown), a second work spindle 20, and a tool post 30. The bed is a base member for supporting the first work spindle, the second work spindle 20, and the tool post 30, etc., and is installed on the floor of a factory or the like. The bed is made of metal such as casting. The bed is a slant bed type, and the support surface that supports the first work spindle, the second work spindle 20, and the tool post 30, etc., is inclined.

[0014] To describe the structure of the second workpiece spindle 20 as shown in the diagram, the second workpiece spindle 20 is capable of holding a workpiece. The second workpiece spindle 20 rotates the workpiece around a rotational axis 120 that is parallel to the horizontally extending Z-axis.

[0015] The second workpiece spindle 20 has a plurality of gripping claws 21 (see Figure 4 below). The plurality of gripping claws 21 are spaced apart from each other in the circumferential direction of the rotational axis 120. Each gripping claw 21 is slidable in the radial direction of the rotational axis 120. The plurality of gripping claws 21 grip the outer circumferential surface of a workpiece by sliding each gripping claw 21 radially inward from the rotational axis 120, or grip the inner circumferential surface of a cylindrical workpiece by sliding each gripping claw 21 radially outward from the rotational axis 120.

[0016] The second workpiece spindle 20 is movable in the Z-axis direction by various feed mechanisms, guide mechanisms, and servo motors.

[0017] The first workpiece spindle (not shown) has the same structure as the second workpiece spindle 20. The first workpiece spindle is positioned opposite the second workpiece spindle 20 in the Z-axis direction. The first workpiece spindle is fixed to the bed.

[0018] The tool post 30 is a turret-type tool post capable of mounting multiple tools. The tool post 30 positions the tools to be used for machining at a predetermined angular position around the pivot axis 110 by moving the multiple tools in the circumferential direction of the pivot axis 110, which extends in the Z-axis direction. The tool post 30 may also be equipped with a milling function that performs workpiece machining by bringing a rotating tool into contact with a stationary workpiece.

[0019] As shown in Figure 3, the machine tool 100 further includes a saddle 31. The saddle 31 is mounted on the bed. The saddle 31 is movable in the Z-axis direction by various feed mechanisms, guide mechanisms, and servo motors.

[0020] The machine tool 100 further comprises a cross feed table 32 and a base 33. The cross feed table 32 is attached to a saddle 31. The cross feed table 32 is movable in the X-axis direction, which is perpendicular to the Z-axis and inclined with respect to the vertical and horizontal directions, by various feed mechanisms, guide mechanisms, and servo motors. The base 33 is attached to the cross feed table 32. The base 33 is movable in the Y'-axis direction, which is perpendicular to the Z-axis and inclined with respect to the X-axis, by various feed mechanisms, guide mechanisms, and servo motors. The base 33 is movable in the Y-axis direction, which is perpendicular to the X-axis and Z-axis, by the interlocking movement of the cross feed table 32 in the X-axis direction and the movement of the base 33 in the Y'-axis direction.

[0021] The tool post 30 is attached to the base 33. In this configuration, the tool post 30 is movable in the X-axis, Y-axis, and Z-axis directions.

[0022] The tool post 30 has a tool post base 39. The tool post base 39 is attached to the base 33. The tool post base 39 is covered by a tool post cover 40.

[0023] The tool post 30 further includes a turret 36. The turret 36 protrudes from the tool post base 39 in the axial direction of the pivot axis 110. The turret 36 is supported by the tool post base 39 so as to be able to rotate around the pivot axis 110. The turret 36 rotates around the pivot axis 110 by receiving rotation from a motor (not shown) mounted on the tool post base 39.

[0024] The swivel body 36 has a plurality of mounting parts 37. For example, the swivel body 36 has 12 mounting parts 37. The plurality of mounting parts 37 are arranged in the circumferential direction of the pivot axis 110. A tool holder 38 can be attached to each mounting part 37. The tool holder 38 can hold a tool T.

[0025] As shown in Figures 1 and 2, the machine tool 100 further comprises a cover body 12 and a front door 13. The cover body 12 partitions the machining area 150 and also forms the exterior of the machine tool 100. The machining area 150 is the space where the workpiece is machined, and is sealed by the cover body 12 and the front door 13 to prevent foreign matter such as chips or coolant from leaking out of the machining area 150.

[0026] The cover body 12 is provided with an opening 12h. The opening 12h opens the processing area 150 to the outside space. The front door 13 is provided in the opening 12h. The front door 13 is mounted on the cover body 12 so as to be slidable in the Z-axis direction. The opening 12h is opened or closed by the sliding motion of the front door 13.

[0027] Figure 4 shows the internal structure of the machine tool (closed state of the workpiece transfer device lid) as viewed in the direction of the rotation axis of the tool post. Referring to Figures 1, 2, and 4, the cover body 12 has a front cover 15, a side cover 18, and a top cover 17.

[0028] The front cover 15 is located on the front of the machine tool 100. In the Z-axis direction, the front cover 15 is adjacent to the opening surface formed by the opening 12h. The side cover 18 is located on the right side of the machine tool 100. The front end of the side cover 18 is connected to the right end of the front cover 15, forming a corner. An operation panel 16 is provided in front of the side cover 18. The control panel 16 houses the control device for the machine tool 100. The ceiling cover 17 is located on the top surface of the machine tool 100. The ceiling cover 17 forms the ceiling of the machining area 150. The ceiling cover 17 is located above the second workpiece spindle 20.

[0029] As shown in Figure 4, the front cover 15 is positioned at a distance from the tool post 30 in the horizontal direction (the front-to-back direction of the machine tool 100) perpendicular to the pivot axis 110 of the tool post 30. The second workpiece spindle 20 is positioned between the tool post 30 and the front cover 15. The rotation axis 120 of the second workpiece spindle 20 is positioned below the pivot axis 110 of the tool post 30. The distance between the rotation axis 120 and the front cover 15 in the front-to-back direction of the machine tool 100 is smaller than the distance between the pivot axis 110 and the front cover 15 in the front-to-back direction of the machine tool 100.

[0030] Figure 5 shows the internal structure of a machine tool as viewed in the direction of the rotation axis of the tool post (with the lid of the workpiece transfer device open).

[0031] Referring to Figures 2, 4, and 5, the machine tool 100 further includes a workpiece transfer device 200. The workpiece transfer device 200 transports the processed workpiece, held on the second workpiece spindle 20, from the processing area 150 to the outside of the machine tool 100.

[0032] As shown in Figures 4 and 5, the workpiece transfer device 200 is located in the machining area 150. The workpiece transfer device 200 is located between the tool post 30 and the front cover 15, above the second workpiece spindle 20. In the front-rear direction of the machine tool 100, the workpiece transfer device 200 is positioned between the tool post 30 and the front cover 15. In the vertical direction, the workpiece transfer device 200 is positioned between the second workpiece spindle 20 and the ceiling cover 17.

[0033] The workpiece transfer device 200 has a cover body 310 and a door 320. The cover body 310 and the door 320 constitute the external appearance of the workpiece transfer device 200.

[0034] The cover body 310 has a cylindrical shape extending in the Z-axis direction. The cover body 310 has an opening 316. The opening 316 is oriented in the axial direction (Z-axis direction) of the pivot center axis 110. The door 320 is provided in the opening 316. The door 320 is rotatably mounted on the cover body 310. The door 320 is operable between a closed state 320A that closes the opening 316 shown in Figure 4 and an open state 320B that opens the opening 316 shown in Figure 5.

[0035] The workpiece transport device 200 further comprises a workpiece transport mechanism 210. The workpiece transport mechanism 210 is housed in a cover body 310. The workpiece transport mechanism 210 is capable of transporting workpieces. The workpiece transport mechanism 210 has a hand 261 (see Figures 7 to 9 below). The hand 261 consists of a robotic hand capable of gripping workpieces.

[0036] While a workpiece is being processed in the processing area 150, the door 320 is in the closed state 320A. When processing of the workpiece held on the second workpiece spindle 20 is complete, the door 320 moves from the closed state 320A to the open state 320B. The workpiece transfer mechanism 210 enters the processing area 150 through the opening 316 and uses the hand 261 to grasp the processed workpiece held on the second workpiece spindle 20. The workpiece transfer mechanism 210 moves the grasped workpiece from the processing area 150 into the interior of the cover body 310. When the workpiece exits the processing area 150, the door 320 moves from the open state 320B to the closed state 320A. Furthermore, the workpiece transfer mechanism 210 moves the workpiece outside the machine tool 100 through the interior of the cover body 310.

[0037] Referring to Figures 1 and 2, the machine tool 100 further includes a workpiece retrieval device 400. The workpiece retrieval device 400 is installed outside the machine tool 100.

[0038] The workpiece recovery device 400 has a bucket 460. The bucket 460 consists of a box capable of accommodating workpieces. The workpiece recovery device 400 is a device for recovering processed workpieces into the bucket 460. The workpiece recovery device 400 is a device for recovering workpieces that have been transported outside the machine tool 100 by the workpiece transport device 200 (workpiece transport mechanism 210) into the bucket 460.

[0039] The workpiece recovery device 400 has a device body 420. The device body 420 is attached to the cover body 12. The device body 420 is provided adjacent to the side cover 18.

[0040] The main body of the device 420 includes a workpiece transport mechanism 410 and a bucket mounting base 427. The workpiece transport mechanism 410 is capable of transporting workpieces. The workpiece transport mechanism 410 consists of a belt conveyor and transports workpieces that have been transported outside the machine tool 100 by the workpiece transport mechanism 210 toward the bucket 460.

[0041] The bucket 460 is detachably attached to the main body 420 of the device. When workpieces are being transported by the workpiece transport mechanism 410, the bucket 460 is attached to the main body 420. When an operator carries the workpieces collected in the bucket 460, the bucket 460 is removed from the main body 420 of the device.

[0042] The bucket mounting base 427 is erected on the floor of a factory or the like where the machine tool 100 is installed. The bucket mounting base 427 has a mounting surface 427a. The mounting surface 427a is provided at a predetermined height above the floor of the factory or the like. The mounting surface 427a extends horizontally. The bucket 460 is placed on the mounting surface 427a. The mounting surface 427a is provided with a positioning mechanism for positioning the bucket 460 at a predetermined position on the mounting surface 427a.

[0043] [Structure of Work Transfer Device] Figure 6 is a diagram showing a partially enlarged view of the internal structure of the machine tool in FIG. 5 (the open state of the cover of the work transfer device). FIGS. 7 to 9 are diagrams showing the operation of the work transfer mechanism in FIG. 6. In FIGS. 7 to 9, the work transfer mechanism 210 viewed in the front-rear direction of the machine tool 100 is shown.

[0044] Figure 10 is a diagram showing the work transfer mechanism (arm in the raised position) in the range surrounded by the two-dot chain line X in FIG. 8. Figure 11 is a diagram showing the work transfer mechanism (arm in the lowered position) in the range surrounded by the two-dot chain line XI in FIG. 9. Figure 12 is a top view showing the transmission mechanism (when the timing belt is normal). Figure 13 is a top view showing the transmission mechanism (when the timing belt is abnormal).

[0045] Figure 14 is a perspective view showing the cover body and the door of the work transfer device. Figure 15 is a perspective view showing the door viewed in the direction indicated by the arrow XV in FIG. 14. Figure 16 is a perspective view showing the door viewed in the direction indicated by the arrow XVI in FIG. 14.

[0046] Figure 17 is a front view showing the machine tool in FIG. 2. Figure 18 is a cross-sectional view showing the machine tool along the line XVIII-XVIII in FIG. 17.

[0047] Figure 19 is a diagram showing a partially enlarged view of the internal structure of the machine tool in FIG. 4 (the closed state of the cover of the work transfer device). In FIG. 19, the tool post 30 positioned closest to the work transfer device 200 in the X-axis direction and the Y-axis direction is shown.

[0048] Figure 20 is a perspective view showing the opening / closing drive mechanism of the door and the detection mechanism for the open state of the door. Figure 21 is a cross-sectional view showing the opening / closing drive mechanism of the door in FIG. 20 (the closed state of the door). Figure 22 is a cross-sectional view showing the opening / closing drive mechanism of the door in FIG. 20 (the open state of the door). Figure 23 is a cross-sectional view showing the detection mechanism for the open state of the door in FIG. 20 (the closed state of the door). Figure 24 is a cross-sectional view showing the detection mechanism for the open state of the door in FIG. 20 (the open state of the door).

[0049] (Embodiment 1) Referring to FIGS. 6 to 9, first, the flow of collecting the machined work held by the second work spindle 20 will be described.

[0050] The workpiece transfer mechanism 210 further comprises an arm 251 and a traveling body 281. The hand 261 is attached to the arm 251. The arm 251 can slide between the raised position shown in Figure 8 and the lowered position shown in Figure 9 within the processing area 150. The arm 251 is mounted on the traveling body 281. The traveling body 281 can slide between the external position shown in Figure 7 and the internal position shown in Figure 8.

[0051] As shown in Figures 6 and 8, when machining of the workpiece held on the second workpiece spindle 20 is complete, the door 320 moves from the closed state 320A to the open state 320B. The traveling body 281 slides toward the machine position. As shown in Figure 9, the arm 251 slides from the raised position toward the lowered position. The hand 261 grips the machined workpiece held on the second workpiece spindle 20. As shown in Figures 6 and 8, the arm 251 slides from the lowered position toward the raised position.

[0052] As shown in Figure 7, the traveling body 281 slides from the inside of the machine to the outside of the machine through the inside of the cover body 310. At the moment the traveling body 281 enters the inside of the cover body 310, the door 320 moves from the open state 320B to the closed state 320A. The arm 251 slides from the raised position to a position directly above the workpiece transport mechanism 410. The hand 261 releases its grip on the workpiece. The workpiece transport mechanism 410 transports the workpiece toward the bucket 460. Through these steps, the processed workpiece is collected in the bucket 460.

[0053] Next, the specific structure of the workpiece transfer mechanism 210 will be described. Referring to Figures 6 to 11, the workpiece transfer mechanism 210 moves the workpiece gripped by the hand 261 along the first direction 101 shown in Figure 6 as the arm 251 slides between the raised and lowered positions.

[0054] In Figure 6, the first direction 101 and the up-down direction 106 are indicated by arrows. The first direction 101 is oblique to the up-down direction 106. For example, the angle α between the first direction 101 and the up-down direction 106 is 8°. The angle α may be in the range of 3° to 15°, or in the range of 5° to 10°. Figure 6 further shows the workpiece W when the arm 251 slides to the lowered position, and the workpiece W' when the arm 251 slides to the raised position. The direction in which the dashed line 140 connecting the center of workpiece W and the center of workpiece W' extends corresponds to the first direction 101.

[0055] As shown in Figures 6, 10, and 11, the workpiece transport mechanism 210 further includes a first servo motor 221, a ball screw 231, and a speed-doubling mechanism 240. The first servo motor 221, the ball screw 231, the speed-doubling mechanism 240, the arm 251, and the hand 261 are mounted on the traveling body 281.

[0056] The first servo motor 221 outputs rotation about a rotation center axis 201 parallel to the first direction 101. The output shaft of the first servo motor 221 extends around the rotation center axis 201. The first servo motor 221 is provided as a power source for the sliding motion of the arm 251 along the first direction 101.

[0057] The ball screw 231 is provided as a motion conversion mechanism that converts the rotational motion output from the first servo motor 221 into linear motion and transmits it toward the arm 251. The ball screw 231 is provided at a distance from the first servo motor 221 in the second direction 102, which is perpendicular to the first direction 101. In this embodiment, the second direction 102 corresponds to the third direction 103 (Z-axis direction) which will be described later.

[0058] The ball screw 231 comprises a screw 232 and a nut 233. The screw 232 extends around a rotation axis 202 parallel to the first direction 101. The screw 232 is supported so as to be rotatable around the rotation axis 202. The nut 233 engages with the screw 232. The nut 233 is fitted onto the outer circumference of the screw 232 via a plurality of rolling elements (not shown). As the screw 232 rotates, the nut 233 slides along the first direction 101.

[0059] The first servo motor 221 is positioned opposite the screw 232 in the second direction 102. The first servo motor 221 is provided in parallel with the screw 232. The first servo motor 221 and the screw 232 extend in the first direction 101 with a gap between them in the second direction 102. As shown in Figure 10, when the arm 251 is positioned in the raised position, the first servo motor 221, the screw 232, the intermediate member 241, and the arm 251 are arranged in the order listed above in the second direction 102 (the third direction 103 described later).

[0060] The arm 251 has an arm shape that extends in the first direction 101. The arm 251 is slidable along the first direction 101 with respect to the intermediate member 241, which will be described later. The arm 251 is supported by a guide mechanism 245 so as to be slidable along the first direction 101. A hand 261 is attached to the arm 251. The hand 261 is attached to the lower end of the arm 251.

[0061] The speed doubling mechanism 240 is located between the ball screw 231 and the arm 251 in the power transmission path from the first servo motor 221. The speed doubling mechanism 240 transmits the linear motion output from the ball screw 231 (nut 233) to the arm 251 with a stroke length doubled. The speed doubling mechanism 240 is located between the first servo motor 221 and the arm 251 in the second direction 102.

[0062] The double-speed mechanism 240 includes an intermediate member 241, a pinion 243, a first rack 246, and a second rack 247.

[0063] The intermediate member 241 extends in the first direction 101. The intermediate member 241 is slidable along the first direction 101 relative to the traveling body 281. The intermediate member 241 is supported by a guide mechanism 244 so as to be slidable along the first direction 101. A nut 233 is attached to the intermediate member 241. The nut 233 is connected to the intermediate member 241 via an angle 236.

[0064] The pinion 243 is attached to the intermediate member 241. The pinion 243 is rotatably supported around a rotational axis 203 that is perpendicular to the first direction 101 and perpendicular to the second direction 102 (the third direction 103 described later). In the first direction 101, the pinion 243 is positioned closer to the lower end of the intermediate member 241 than to the upper end.

[0065] The first rack 246 and the second rack 247 each extend in the first direction 101. Each rack of the first rack 246 and the second rack 247 engages with a pinion 243. The pinion 243 is located between the first rack 246 and the second rack 247 in the second direction 102. The first rack 246 is attached to the traveling body 281. The second rack 247 is attached to the arm 251.

[0066] As shown in Figures 8 and 10, when the arm 251 is positioned in the raised position, the screw 232, the intermediate member 241, and the arm 251 are arranged in the order listed above in the second direction 102. The first rack 246 extends downward along the first direction 101 from the engagement position of the first rack 246 with respect to the pinion 243. The second rack 247 extends upward along the first direction 101 from the engagement position of the second rack 247 with respect to the pinion 243.

[0067] As shown in Figures 9 and 11, when the arm 251 is positioned in the lowered position, the intermediate member 241 is positioned shifted downward along the first direction 101 relative to the screw 232, and the arm 251 is positioned shifted downward along the first direction 101 relative to the intermediate member 241. The first rack 246 extends upward along the first direction 101 from the engagement position of the first rack 246 with respect to the pinion 243. The second rack 247 extends downward along the first direction 101 from the engagement position of the second rack 247 with respect to the pinion 243.

[0068] When moving the arm 251 from the raised position to the lowered position, the first servo motor 221 outputs rotation in one direction along the circumferential direction of the rotation center axis 201. The rotation from the first servo motor 221 is transmitted to the screw 232 via the transmission mechanism 270, which will be described later. The screw 232 rotates in one direction along the circumferential direction of the rotation center axis 202. The nut 233 and the intermediate member 241 move downward together along the first direction 101. As the intermediate member 241 moves downward, the pinion 243 rotates in one direction along the circumferential direction of the rotation center axis 203 while engaging with the first rack 246. The rotation of the pinion 243 is transmitted to the second rack 247, causing the arm 251 to move downward along the first direction 101. At this time, the downward stroke length of the hand 261 is obtained by adding the downward stroke length of the intermediate member 241 and the downward stroke length of the arm 251 relative to the intermediate member 241.

[0069] When moving the arm 251 from the lowered position to the raised position, the first servo motor 221 outputs rotation in the other direction along the circumferential direction of the rotation center axis 201. The rotation from the first servo motor 221 is transmitted to the screw 232 via the transmission mechanism 270, which will be described later. The screw 232 rotates in the other direction along the circumferential direction of the rotation center axis 202. The nut 233 and the intermediate member 241 move together as a unit and rise along the first direction 101. As the intermediate member 241 rises, the pinion 243 rotates in the other direction along the circumferential direction of the rotation center axis 203 while engaging with the first rack 246. The rotation of the pinion 243 is transmitted to the second rack 247, causing the arm 251 to rise along the first direction 101. At this time, the upward stroke length of the hand 261 is obtained by adding the upward stroke length of the intermediate member 241 and the upward stroke length of the arm 251 relative to the intermediate member 241.

[0070] Referring to Figures 10 to 12, the workpiece transport mechanism 210 further includes a transmission mechanism 270. The transmission mechanism 270 is mounted on the traveling body 281. The transmission mechanism 270 is attached to the upper ends of the first servo motor 221 and the ball screw 231. The transmission mechanism 270 transmits rotation from the first servo motor 221 to the screw 232.

[0071] The transmission mechanism 270 includes a first pulley 226, a second pulley 227, and a timing belt 271. The first pulley 226 is connected to the output shaft of the first servo motor 221. The first pulley 226 receives the rotational motion output from the first servo motor 221 and rotates around the rotational axis 201. The second pulley 227 is connected to the screw 232. The second pulley 227 rotates together with the screw 232 around the rotational axis 202. The timing belt 271 is an annular belt. The timing belt 271 is stretched between the first pulley 226 and the second pulley 227. The rotation from the first servo motor 221 is transmitted to the screw 232 via the first pulley 226, the timing belt 271, and the second pulley 227.

[0072] The workpiece transport mechanism 210 further comprises a first rotating body 273 and a second rotating body 272. The first rotating body 273 is connected to a second pulley 227. The first rotating body 273 has a disc shape centered on the rotational axis 202. The first rotating body 273 rotates together with the screw 232 and the second pulley 227 around the rotational axis 202. The first rotating body 273 has a first locking portion 274. The first locking portion 274 has a stepped shape on the outer circumferential surface of the first rotating body 273 in the radial direction of the rotational axis 202. The first rotating body 273 has a plurality of first locking portions 274. The plurality of first locking portions 274 are provided spaced apart from each other in the circumferential direction of the rotational axis 202.

[0073] The second rotating body 272 is positioned between the first pulley 226 and the second pulley 227. The second rotating body 272 is rotatably supported about a rotation axis 203 parallel to the first direction 101. Viewed in the first direction 101, the rotation axis 203 is located between the rotation axes 201 and 202. Viewed in the first direction 101, the rotation axis 203 intersects a virtual line connecting the rotation axes 201 and 202. The distance between the rotation axes 202 and 203 may be greater than or equal to the distance between the rotation axes 201 and 203. The first rotating body 273 and the second rotating body 272 are provided in the same plane perpendicular to the rotation axes 202 and 203.

[0074] The second rotating body 272 has a second locking portion 277. The second locking portion 277 faces the outer circumferential surface of the first rotating body 273 with a gap between them in a planar direction perpendicular to the rotational axis 203. The second locking portion 277 has a hook shape that allows it to hook onto the first locking portion 274 from one direction along the circumferential direction of the rotational axis 202.

[0075] The second rotating body 272 further has a shaft portion 275. The shaft portion 275 is located away from the second locking portion 277 in the circumferential direction of the rotational axis 203. The shaft portion 275 has an axial shape that extends parallel to the rotational axis 203. The shaft portion 275 is positioned on the outside of the annular timing belt 271.

[0076] The workpiece transport mechanism 210 further includes an elastic member 278. The elastic member 278 consists of, for example, a coil spring centered on the rotational axis 203. The elastic member 278 imparts an elastic force to the second rotating body 272 along the direction of rotation of the second rotating body 272. The elastic member 278 imparts an elastic force to the second rotating body 272 in a clockwise direction around the rotational axis 203 in Figure 12.

[0077] Figure 12 shows the transmission mechanism 270 under normal conditions of the timing belt 271. Figure 13 shows the transmission mechanism 270 under abnormal conditions of the timing belt 271 (when the timing belt 271 breaks). Referring to Figures 12 and 13, the second rotating body 272 operates between a first state 272A (the state of the second rotating body 272 shown in Figure 12), in which the second locking portion 277 is positioned away from the first rotating body 273 by being locked by the timing belt 271, and a second state 272B (the state of the second rotating body 272 shown in Figure 13), in which, when the locking by the timing belt 271 is released, the second rotating body 272 rotates under the elastic force of the elastic member 278, and the second locking portion 277 locks with the first locking portion 274.

[0078] As shown in Figure 12, the second rotating body 272 is biased clockwise around the rotational axis 203 in Figure 12 by the elastic force from the elastic member 278. The shaft portion 275 is in contact with the timing belt 271 from the outside of the annular timing belt 271. By locking the shaft portion 275 to the timing belt 271, the second locking portion 277 is positioned away from the first rotating body 273. At this time, the first rotating body 273 can rotate freely around the rotational axis 202.

[0079] As shown in Figure 13, if the timing belt 271 breaks, the arm 251 slides toward the lowered position due to its own weight or the weight of the workpiece. As the arm 251 slides toward the lowered position, the first rotating body 273 rotates counterclockwise around the rotation center axis 202 in Figure 13. On the other hand, if the timing belt 271 breaks, the locking of the second rotating body 272 (shaft portion 275) by the timing belt 271 is released. The second rotating body 272 rotates clockwise around the rotation center axis 203 in Figure 13 due to the elastic force of the elastic member 278. As the second rotating body 272 rotates, the second locking portion 277 moves closer to the outer circumferential surface of the first rotating body 273. At this time, the rotation of the first rotating body 273 is restricted as the second locking portion 277 locks with the first locking portion 274. As a result, the arm 251 is prevented from sliding toward the lowered position, and the workpiece gripped by the hand 261 is prevented from falling.

[0080] The workpiece transfer mechanism 210 further includes a sensor 276. The sensor 276 is capable of sensing the movement of the second rotating body 272. The sensor 276 is capable of sensing the movement of the second rotating body 272 between the first state 272A and the second state 272B.

[0081] Sensor 276 is, for example, a proximity sensor. Sensor 276 is attached to the traveling body 281. In the first state 272A of the second rotating body 272, sensor 276 is positioned opposite the shaft portion 275 with a gap between them. At this time, sensor 276 detects the shaft portion 275. When the second rotating body 272 moves from the first state 272A to the second state 272B, the shaft portion 275 moves away from sensor 276. At this time, detection of the shaft portion 275 by sensor 276 is eliminated. By sensing the movement of the second rotating body 272 from the first state 272A to the second state 272B, sensor 276 can detect a belt break in the timing belt 271.

[0082] Furthermore, the object detected by the sensor 276 is not limited to the shaft portion 275, but may be other parts of the second rotating body 272. Also, in the present invention, the type of sensor for sensing the operation of the second rotating body is not particularly limited. The sensor may be a non-contact type sensor such as the proximity sensor described above, or a contact type sensor such as a limit switch.

[0083] Referring to Figures 5 to 9, the workpiece transfer mechanism 210 moves the workpiece gripped by the hand 261 along the third direction 103 as the traveling body 281 slides between the internal position shown in Figure 8 and the external position shown in Figure 7.

[0084] In Figures 7 to 11, the third direction 103 is indicated by an arrow. The third direction 103 is perpendicular to the first direction 101 and parallel to the horizontal direction. The third direction 103 corresponds to the Z-axis direction. The third direction 103 corresponds to the axial direction of the pivot center axis 110 and the rotation center axis 120.

[0085] The workpiece transport mechanism 210 has a horizontal column 289. The horizontal column 289 extends in a third direction 103. The horizontal column 289 consists of a column body in which the third direction 103 corresponds to the longitudinal direction. The horizontal column 289 extends from the processing area 150, through the side cover 18, to the outside of the machine tool 100 (in Figures 7 to 9, the cover line of the side cover 18 is shown by a dashed line).

[0086] The horizontal column 289 is located between the tool post 30 and the traveling body 281 in the front-rear direction of the machine tool 100. In the vertical direction 106, the horizontal column 289 is positioned closer to the upper end than the lower end of the workpiece transport mechanism 210. The horizontal column 289 is supported at a predetermined height from the floor surface on which the machine tool 100 is installed. The horizontal column 289 is positioned above the rotational axis 120. The horizontal column 289 is positioned above the slewing axis 110. The horizontal column 289 is positioned above the hand 261 when the arm 251 slides to the raised position. The horizontal column 289 is positioned above the dog 371, switch 372, and piston cylinder 381 (see Figure 20), which will be described later.

[0087] The workpiece transport mechanism 210 further includes a second servo motor 286, a feed mechanism 287, and a guide mechanism 288.

[0088] The running body 281 is slidable along the third direction 103. The guide mechanism 288 supports the running body 281 so that it can slide along the third direction 103. As an example, the guide mechanism 288 consists of a linear guide having a guide rail and a slider. The guide rail extends in the third direction 103. The guide rail is attached to a cross column 289. The slider is engaged with the guide rail via a plurality of rolling elements. The slider is slidable along the guide rail in the third direction 103. The running body 281 is attached to the slider.

[0089] The second servo motor 286 is mounted on the vehicle body 281. The second servo motor 286 is provided as a power source for the sliding motion of the vehicle body 281 along the third direction 103. The feed mechanism 287 converts the rotational motion output from the second servo motor 286 into linear motion in the third direction 103 and transmits it to the vehicle body 281. As an example, the feed mechanism 287 has a rack and a pinion. The rack extends in the third direction 103. The rack is attached to the cross column 289. The pinion is connected to the output shaft of the second servo motor 286 via a reduction gear or the like. The pinion is engaged with the rack.

[0090] Referring to Figures 2 and 5, the cover body 310 is attached to the ceiling cover 17. The cover body 310 is positioned vertically between the ceiling cover 17 and the second workpiece spindle 20.

[0091] Referring to Figures 14, 17, and 18, the cover body 310 (cover main body portion 341, described later) further has a front portion 310f. The front portion 310f extends in the vertical direction and in a planar direction including the third direction 103. A gap 346 is provided between the cover body 310 and the front cover 15. The front portion 310f faces the front cover 15 through the gap 346. In the vertical direction, the gap 346 extends between the second work spindle 20 and the ceiling cover 17.

[0092] The machine tool 100 further has line bodies 330. The line bodies 330 may be pipes for carrying fluids such as gas or liquid, or they may be wiring for carrying electricity. The machine tool 100 has a plurality of line bodies 330. The line bodies 330 are routed in the gap 346. The line bodies 330 extend from the second work spindle 20 and are supported by the ceiling cover 17. The plurality of line bodies 330 extend from the second work spindle 20 toward the ceiling cover 17 in the gap 346, spaced apart from each other in at least the third direction 103.

[0093] One end of the line body 330 is connected to the second work spindle 20. The other end of the line body 330 is fixed to the ceiling cover 17. As the second work spindle 20 moves in the Z-axis direction, one end of the line body 330 swings in the Z-axis direction, while the other end of the line body 330 remains fixed to the ceiling cover 17.

[0094] Referring to Figures 1 to 24, the configuration of the workpiece transfer device 200 and the machine tool 100 in Embodiment 1 of this invention is summarized.

[0095] The workpiece transfer device 200 in this embodiment includes a first servo motor 221, a ball screw 231 having a screw 232 to which rotation from the first servo motor 221 is input, and a nut 233 that engages with the screw 232, an intermediate member 241 to which the nut 233 is attached and which is slidable along a first direction 101, a double-speed mechanism 240 having a pinion 243 attached to the intermediate member 241, a first rack 246 and a second rack 247 that engage with the pinion 243 and extend in the first direction 101, an arm 251 to which the second rack 247 is attached and which is slidable relative to the intermediate member 241 in the first direction 101, and a hand 261 attached to the arm 251.

[0096] With this configuration, the rotational motion output from the first servo motor 221 is converted into linear motion by the ball screw 231, and this linear motion is transmitted to the arm 251 via the speed-doubling mechanism 240, thereby stroking the hand for gripping the workpiece. In this case, by using the first servo motor 221 as the power source for the arm 251, the workpiece transfer device 200 can be made more compact in the first direction 101 compared to when a piston cylinder is used. Furthermore, by using the speed-doubling mechanism 240, the overall length of the screw 232 in the first direction 101 can be kept small while ensuring a sufficient stroke length for the hand 261. Therefore, the workpiece transfer device 200 can be made more compact.

[0097] Furthermore, by using the first servo motor 221, an additional effect is achieved in which the arm 251 can be slid to any position along the first direction 101.

[0098] Furthermore, the first direction 101 is oblique to the vertical direction 106. With this configuration, the workpiece transport device 200 can be made more compact in the vertical direction compared to the case where the first direction 101 is parallel to the vertical direction 106.

[0099] Furthermore, the first servo motor 221 is positioned opposite the screw 232 in a second direction 102 that is perpendicular to the first direction 101. The workpiece transport device 200 further includes a transmission mechanism 270 that transmits rotation from the first servo motor 221 to the screw 232.

[0100] With this configuration, the installation of the transmission mechanism 270 allows the first servo motor 221 to be positioned opposite the screw 232 in the second direction 102. As a result, the first servo motor 221 is positioned in parallel with the screw 232, allowing the workpiece transport device 200 to be configured compactly in the first direction 101.

[0101] The transmission mechanism 270 also includes a first pulley 226 connected to the output shaft of the first servo motor 221, a second pulley 227 connected to the screw 232, and a timing belt 271 stretched between the first pulley 226 and the second pulley 227. The workpiece transport device 200 further includes a first rotating body 273 having a first locking portion 274 and connected to the second pulley 227, a second rotating body 272 having a second locking portion 277 and rotatably supported between the first pulley 226 and the second pulley 227, and an elastic member 278 that applies an elastic force to the second rotating body 272 along the rotational direction of the second rotating body 272. The second rotating body 272 operates between a first state 272A in which the second locking portion 277 is positioned away from the first rotating body 273 by being locked by the timing belt 271, and a second state 272B in which, when the locking by the timing belt 271 is released, the second rotating body 272 rotates due to the elastic force of the elastic member 278, and the second locking portion 277 locks with the first locking portion 274. The workpiece transfer device 200 further includes a sensor 276 capable of sensing the operation of the second rotating body 272.

[0102] In this configuration, the rotation output from the first servo motor 221 is transmitted to the screw 232 via the first pulley 226, the timing belt 271, and the second pulley 227 in that order. If the timing belt 271 breaks, the locking of the second rotating body 272 by the timing belt 271 is released. The second rotating body 272 moves from the first state 272A to the second state 272B upon receiving the elastic force from the elastic member, and the second locking part 277 locks with the first locking part 274. This restricts the rotation of the screw 232 and prevents the arm 251 from descending along the first direction 101 due to the weight of the workpiece. Furthermore, the timing belt 271 breakage is detected by sensing the movement of the second rotating body 272 from the first state 272A to the second state 272B using the sensor 276. In this configuration, the second rotating body 272 is responsible for both the braking mechanism in case of belt breakage and the belt breakage detection mechanism, which allows for a simple construction of the workpiece transport device 200.

[0103] Furthermore, the workpiece transfer device 200 includes a first servo motor 221, a ball screw 231, a double-speed mechanism 240, an arm 251 and a hand 261, a traveling body 281 that is slidable along a third direction 103 that is perpendicular to the first direction 101 and parallel to the horizontal direction, and a second servo motor 286 provided as a power source for the sliding motion of the traveling body 281 along the third direction 103.

[0104] With this configuration, by using the second servo motor 286 as the power source for the traveling body 281, the workpiece transport device 200 can be made more compact in the third direction 103 compared to the case where a piston cylinder is used.

[0105] The machine tool 100 in this embodiment includes a turret-type tool post 30 that can rotate around a pivot axis 110 extending in the horizontal direction, a front cover 15 positioned at a distance from the tool post 30 in a horizontal direction perpendicular to the pivot axis 110, a second work spindle 20 positioned between the tool post 30 and the front cover 15 and rotating the workpiece around a rotation axis 120 extending parallel to the pivot axis 110, and a workpiece transfer device 200 positioned between the tool post 30 and the front cover 15 and above the second work spindle 20.

[0106] With this configuration, the workpiece transfer device 200 can be placed in the limited space between the tool post 30 and the front cover 15, above the second workpiece spindle 20.

[0107] Furthermore, the workpiece transfer device 200 has an opening 316 that opens in a direction parallel to the pivot axis 110, and further comprises a cover body 310 that houses a first servo motor 221, a ball screw 231, a double-speed mechanism 240, an arm 251 and a hand 261, and a door 320 that is rotatably attached to the cover body 310 and opens and closes the opening 316.

[0108] With this configuration, the door 320 is rotated between a closed state 320A that closes the opening 316 and an open state 320B that opens the opening 316. In this case, when the door 320 is in the closed state 320A, foreign matter such as chips or coolant generated during workpiece processing can be prevented from entering the inside of the cover body 310. Also, when the door 320 is in the open state 320B, the hand 261 for gripping the workpiece can be moved forward and backward relative to the processing area 150.

[0109] A gap 346 is provided between the cover body 310 and the front cover 15. The machine tool 100 further comprises a line body 330 which includes at least one of piping and wiring and is routed in the gap 346.

[0110] With this configuration, the line body 330 can be routed by utilizing the gap 346 between the cover body 310 and the front cover 15, which is secured by the compact configuration of the workpiece transport device 200.

[0111] Furthermore, the machine tool 100 is further equipped with a ceiling cover 17. The line body 330 extends from the second workpiece spindle 20 and is supported by the ceiling cover 17.

[0112] With this configuration, since the line body 330 extends vertically between the second work spindle 20 and the ceiling cover 17, the line body 330 can be routed and secured even in the narrow gap 346 between the cover body 310 and the front cover 15.

[0113] Furthermore, the machine tool 100 is further equipped with a ceiling cover 17. The cover body 310 is attached to the ceiling cover 17.

[0114] With this configuration, the space up to the ceiling of the machine tool 100 can be efficiently utilized to install the workpiece transport device 200.

[0115] As shown in Figures 10 and 11, the intermediate member 241 is configured to slide along a first direction 101 relative to the traveling body (main body member) 281. The workpiece transport mechanism 210 further includes a guide mechanism 244. The guide mechanism 244 guides the intermediate member 241 along the first direction 101. As an example, the guide mechanism 244 consists of a linear guide having a guide rail attached to the intermediate member 241 and a slider attached to the traveling body 281 and fitted into the guide rail. The arm 251 is also configured to slide along a first direction 101 relative to the intermediate member 241. The workpiece transport mechanism 210 further includes a guide mechanism 245. The guide mechanism 245 guides the arm 251 along the first direction 101. As an example, the guide mechanism 245 consists of a linear guide having a guide rail attached to the intermediate member 241 and a slider attached to the arm 251 and fitted into the guide rail.

[0116] (Embodiment 2) In this embodiment, the structure of the workpiece transport device 200 will be described with reference to the cover body 310. The structure of the cover body 310 will be described with reference to Figures 14 to 18. The cover body 310 has a cover main body portion 341. The cover main body portion 341 has a cylindrical shape extending in the third direction 103 (Z-axis direction). The cover main body portion 341 forms a first internal space 350. The cover main body portion 341 houses the workpiece transport mechanism 210 in the first internal space 350.

[0117] The cover body 310 (cover main body portion 341) has, in addition to the opening 316, an upper opening 317 and a cover-side opening 318. The opening 316 faces in a direction parallel to the pivot axis 110 (third direction 103). The upper opening 317 faces upward. The upper opening 317 is superimposed on the ceiling cover 17. The cover-side opening 318 faces in the third direction 103. The opening surface formed by the opening 316 and the opening surface formed by the cover-side opening 318 face each other in the third direction 103. The cover body 310 communicates with the cylindrical cover 426 (see Figures 1 and 2), which will be described later, through the cover-side opening 318.

[0118] The door 320 is attached to the cover body 310 so as to be rotatable about the pivot axis 301. The pivot axis 301 extends in the vertical direction. The pivot axis 301 is located at the front end of the cover body 310 of the machine tool 100. The pivot axis 301 is located in front of the machine tool 100, beyond the front portion 310f.

[0119] The door 320 operates between a closed state 320A, which closes the opening 316 shown in Figures 4 and 14, and an open state 320B, which opens the opening 316 shown in Figures 5 and 6. The door 320 rotates around the pivot axis 301 in a direction that approaches the front door 13 in Figure 1. In the open state 320B, the door 320 is positioned to overlap the front door 13 (window 14).

[0120] The cover body 310 further has a protrusion 342. The protrusion 342 has a convex shape that protrudes from the cover body 341 (front portion 310f) when viewed from outside the first internal space 350. The protrusion 342 forms a second internal space 360. The second internal space 360 ​​is a space continuous with the first internal space 350. The volume of the second internal space 360 ​​is smaller than the volume of the first internal space 350.

[0121] The protruding portion 342 extends vertically, forming a convex shape that protrudes from the front portion 310f when viewed from outside the first internal space 350. The length of the protruding portion 342 in the vertical direction is greater than the length (width) of the protruding portion 342 in the third direction 103. The protruding portion 342 is located adjacent to the opening 316 in the third direction 103. The protruding portion 342 is located closer to the opening 316 than to the cover-side opening 318 in the third direction 103. The distance between the opening 316 and the protruding portion 342 in the third direction 103 is less than the distance between the protruding portion 342 and the cover-side opening 318 in the third direction 103.

[0122] As shown in Figures 17 and 18, a second gap 346 (gap 346) is provided between the cover body portion 341 (front portion 310f) and the front cover 15, at a position adjacent to the protrusion 342 in the axial direction (third direction 103) of the pivot axis 110. The protruding length of the protrusion 342 from the front portion 310f is smaller than the distance between the front portion 310f and the front cover 15 (the size of the second gap 346 in the front-rear direction of the machine tool 100).

[0123] The second gap 346 is located further back than the protruding portion 342 when viewed from the opening 12h (see Figure 1) where the front door 13 is positioned. The aforementioned multiple line bodies 330 are routed through the second gap 346.

[0124] Referring to Figures 14 to 16 and Figure 19, the door 320 is provided with a recess 322. The recess 322 has a concave shape that recesses toward the first internal space 350 when the door 320 is in the closed state 320A. The door 320 has a main surface 321. When the door 320 is in the closed state 320A, the main surface 321 consists of a plane perpendicular to the third direction 103. The recess 322 forms a step on the main surface 321 that is recessed toward the third direction 103.

[0125] In Figure 19, the tool post 30 is positioned closest to the workpiece transport device 200 in the X-axis and Y-axis directions shown in Figure 3. In this case, when viewed in the axial direction of the pivot axis 110 (third direction 103), the maximum range 302 over which the tool mounted on the tool post 30 moves as the tool post 30 rotates coincides with the recess 322.

[0126] The maximum range 302 is indicated by an arc centered on the pivot axis 110. The arc corresponds to the trajectory traced by the tip of the tool with the maximum tool length mounted on the tool post 30 as the tool post 30 rotates. Viewed in the axial direction (third direction 103) of the pivot axis 110, at least a portion of the recess 322 is located radially inward from the pivot axis 110 than the arc shown in the maximum range 302.

[0127] Referring to Figures 20 to 22, the workpiece transfer device 200 further includes a piston cylinder 381. The piston cylinder 381 is provided as an actuator for operating the door 320 between a closed state 320A and an open state 320B.

[0128] The piston cylinder 381 has a cylinder body 383 and a rod 382. The cylinder body 383 is housed in a first internal space 350. In the third direction 103, the cylinder body 383 is positioned opposite the opening surface formed by the opening 316 at a distance from it. The cylinder body 383 is attached to the cover body 310 (cover body portion 341). The cylinder body 383 is attached to the front portion 310f. The cylinder body 383 is rotatably mounted to the cover body 310 around a pivot axis 307 that extends in the vertical direction.

[0129] The rod 382 extends from the cylinder body 383 toward the opening surface formed by the opening 316. The tip of the rod 382 is attached to the door 320. The tip of the rod 382 is rotatably attached to the door 320 around a pivot axis 306 that extends in the vertical direction.

[0130] When a fluid such as air is supplied to the cylinder body 383, the rod 382 shortens or extends. As shown in Figure 21, the piston cylinder 381 moves the door 320 from the open state 320B to the closed state 320A as the rod 382 shortens. As shown in Figure 22, the piston cylinder 381 moves the door 320 from the closed state 320A to the open state 320B as the rod 382 extends.

[0131] Referring to Figures 20, 23, and 24, the workpiece transfer device 200 further includes a dock 371 and a switch 372. The dock 371 and the switch 372 are capable of detecting the open state 320B of the door 320.

[0132] The dog 371 is attached to the door 320. The dog 371 is attached to the door 320 via an angle 376. The dog 371 is located radially outward from the pivot axis 301. The dog 371 moves circumferentially around the pivot axis 301 as the door 320 operates between the closed state 320A and the open state 320B. The second internal space 360 ​​is located on the trajectory of the dog 371 as it moves circumferentially around the pivot axis 301.

[0133] Switch 372 is a limit switch operated by the dog 371 when the door 320 is in the open state 320B. Switch 372 is housed in the first internal space 350. Switch 372 is attached to the cover body 310 (cover main body 341). Switch 372 is attached to the front part 310f. Switch 372 is located in the opening 316.

[0134] As shown in Figure 23, when the door 320 is in the closed state 320A, the dock 371 is located in the second internal space 360. In the top view shown in Figure 23, the angle 376 protrudes from the door 320 in the third direction 103 in the first internal space 350. The dock 371 protrudes from the angle 376 in a direction perpendicular to the third direction 103 (towards the front of the machine tool 100) and enters the second internal space 360 ​​from the first internal space 350. In the vertical direction, the dock 371 is housed closer to the lower end than the upper end of the second internal space 360.

[0135] As shown in Figures 20 and 24, when the door 320 is in the open state 320B, the dog 371 has retracted from the second internal space 360. In the top view shown in Figure 24, the angle 376 protrudes from the door 320 outside the first internal space 350 in a direction perpendicular to the third direction 103 (towards the rear of the machine tool 100). The dog 371 protrudes from the angle 376 toward the opening 316 (first internal space 350). The dog 371 overlaps with the operating part 372p of the switch 372. The dog 371 presses down on the operating part 372p, and the operating part 372p strokes, thereby operating the switch 372. The operation of the switch 372 by the dog 371 detects the open state 320B of the door 320.

[0136] Referring to Figures 5, 6, 14, and 20, a first gap 347 is provided between the workpiece transport mechanism 210 and the cover body 310 (cover main body 341). The first gap 347 is provided between the workpiece transport mechanism 210 and the front portion 310f. The first gap 347 extends in the third direction 103 (Z-axis direction). The first gap 347 widens from the upper end to the lower end of the workpiece transport mechanism 210. The size of the first gap 347 in the front-rear direction of the machine tool 100 increases in the vertical direction from the upper end to the lower end of the workpiece transport mechanism 210. The switch 372 is provided in the first gap 347. The switch 372 is positioned in the first gap 347 closer to the lower end of the workpiece transport mechanism 210 than to the upper end of the workpiece transport mechanism 210.

[0137] As shown in Figures 5 and 14, the cover body 310 (cover main body 341) further has an upper surface 311 and a bottom surface 312. The upper surface 311 is located at the top of the cover body 310. The upper opening 317 opens into the upper surface 311. The upper surface 311 is superimposed on the ceiling cover 17. The bottom surface 312 is located at the bottom of the cover body 310. The bottom surface 312 faces the second workpiece spindle 20 in the vertical direction.

[0138] The size of the first gap 347 in the front-rear direction of the machine tool 100 increases in the vertical direction as it approaches the bottom surface 312 from the top surface 311. The switch 372 is positioned closer to the bottom surface 312 than to the top surface 311 in the vertical direction. The distance between the switch 372 and the bottom surface 312 in the vertical direction is smaller than the distance between the switch 372 and the top surface 311 in the vertical direction.

[0139] The piston cylinder 381 is located in the first gap 347. The piston cylinder 381 is positioned in the first gap 347 closer to the lower end of the workpiece transport mechanism 210 than to the upper end of the workpiece transport mechanism 210. In the vertical direction, the piston cylinder 381 is positioned closer to the bottom surface 312 than to the top surface 311. The distance between the piston cylinder 381 and the bottom surface 312 in the vertical direction is smaller than the distance between the piston cylinder 381 and the top surface 311 in the vertical direction. The piston cylinder 381 is located below the switch 372.

[0140] Referring to Figures 5 and 6, the workpiece transport device 200 further includes a sensor 391 for detecting the closed state 320A of the door 320. The sensor 391 consists of, for example, a non-contact safety switch.

[0141] If the control device of the machine tool 100 commands the piston cylinder 381 to shorten the rod 382, ​​but the switch 372 detects that the door 320 is in the open state 320B and the sensor 391 does not detect that the door 320 is in the closed state 320A, the control device determines that the door 320 is in the open state 320B. In this case, the control device may execute control to restrict the movement of the front door 13 (see Figure 1) to the open state.

[0142] On the other hand, if the control device of the machine tool 100 commands the piston cylinder 381 to extend the rod 382, ​​but the switch 372 does not detect the door 320 in the open state 320B, and the sensor 391 detects the door 320 in the closed state 320A, the control device determines that the door 320 is in the closed state 320A. In this case, the control device may stop the drive of the second servo motor 286 and execute control to stop the operation of the machine tool 100.

[0143] Referring to Figures 1 to 24, the configuration of the workpiece transfer device 200 and the machine tool 100 in Embodiment 2 of this invention is summarized.

[0144] The workpiece transport device 200 in this embodiment includes a workpiece transport mechanism 210 capable of transporting workpieces, a cover body 310 having a cover body portion 341 that includes an opening 316 and forms a first internal space 350, and housing the workpiece transport mechanism 210 in the first internal space 350, a door 320 that is rotatably attached to the cover body 310 and is capable of operating between a closed state 320A that closes the opening 316 and an open state 320B that opens the opening 316, a dog 371 attached to the door 320, and a switch 372 attached to the cover body 310 that is operated by the dog 371 when the door 320 is in the open state. The cover body 310 has a convex shape that protrudes from the cover body 341 when viewed from the outside of the first internal space 350, and further has a protruding portion 342 that forms a second internal space 360 ​​in which the dog 371 is positioned when the door 320 is in the closed state 320A, and the dog 371 retracts when the door 320 is in the open state 320B.

[0145] With this configuration, as the door 320 rotates between the closed state 320A and the open state 320B, the dog 371 moves forward and backward relative to the second internal space 360 ​​formed by the protrusion 342. In this case, the protrusion 342 has a convex shape that protrudes from the cover body 341 when viewed from outside the first internal space 350 that houses the workpiece transport mechanism 210. Therefore, the workpiece transport device 200 can be made more compact compared to the case where the cover line of the cover body 341 is enlarged overall.

[0146] Furthermore, the workpiece transport mechanism 210 includes an arm 251 that can slide along a first direction 101 oblique to the vertical direction 106, and a hand 261 attached to the arm 251. A first gap 347 is provided between the workpiece transport mechanism 210 and the cover body 341, which widens from the upper end to the lower end of the workpiece transport mechanism 210. The switch 372 is positioned in the first gap 347, closer to the lower end of the workpiece transport mechanism 210 than to the upper end of the workpiece transport mechanism 210.

[0147] With this configuration, by setting the sliding direction of the arm 251 to a first direction 101 oblique to the vertical direction 106, a first gap 347 is provided between the workpiece transport mechanism 210 and the cover body 341, which widens from the upper end to the lower end of the workpiece transport mechanism 210. In this case, the switch 372 can be placed using the relatively large space secured in the first gap 347, which is closer to the lower end of the workpiece transport mechanism 210 than to the upper end of the workpiece transport mechanism 210.

[0148] Furthermore, the workpiece transport device 200 is positioned in the first gap 347 closer to the lower end of the workpiece transport mechanism 210 than to the upper end of the workpiece transport mechanism 210, and further includes a piston cylinder 381 that operates the door 320 between a closed state 320A and an open state 320B.

[0149] With this configuration, the piston cylinder 381 can be positioned using the relatively large space secured in the first gap 347, which is located closer to the lower end of the workpiece transport mechanism 210 than to the upper end of the workpiece transport mechanism 210.

[0150] The machine tool 100 in this embodiment includes a turret-type tool post 30 that can rotate around a pivot axis 110 extending horizontally, a front cover 15 positioned at a distance from the tool post 30 in a horizontal direction perpendicular to the pivot axis 110, a second work spindle 20 positioned between the tool post 30 and the front cover 15 and rotating the workpiece around a rotation axis 120 extending parallel to the pivot axis 110, and a workpiece transfer device 200 positioned between the tool post 30 and the front cover 15 and above the second work spindle 20. The opening 316 opens in a direction parallel to the pivot axis 110.

[0151] With this configuration, the workpiece transfer device 200 can be placed in the limited space between the tool post 30 and the front cover 15, above the second workpiece spindle 20.

[0152] Furthermore, a second gap 346 is provided between the cover body 341 and the front cover 15, in the axial direction of the pivot axis 110, adjacent to the protruding portion 342. The machine tool 100 further comprises a line body 330 which includes at least one of piping and wiring and is routed in the second gap 346.

[0153] With this configuration, the line body 330 can be routed using the second gap 346, which is secured between the cover body 341 and the front cover 15, and is located adjacent to the protrusion 342 in the axial direction of the pivot center axis 110.

[0154] Furthermore, the door 320 is provided with a recess 322 that recesses toward the first internal space 350 when the door 320 is in the closed state 320A. When the tool post 30 is positioned closest to the workpiece transport device 200, the maximum range 302 over which the tool T mounted on the tool post 30 moves in conjunction with the rotational movement of the tool post 30, when viewed in the axial direction of the pivot axis 110, coincides with the recess 322.

[0155] With this configuration, the workpiece transport device 200 can be positioned closer to the tool rest 30 while avoiding interference between the tool T mounted on the tool rest 30 and the door 320.

[0156] [Structure of the workpiece recovery device] Figure 25 is a perspective view showing the external appearance of the machine tool in Figure 1 (with the workpiece recovery device bucket attached). Figure 26 is a perspective view showing the external appearance of the machine tool in Figure 1 (with the workpiece recovery device bucket removed). Figure 27 is a cross-sectional view showing the workpiece recovery device in Figure 25 (with the first lid of the bucket closed). Figure 28 is a cross-sectional view showing the workpiece recovery device in Figure 25 (with the first lid of the bucket open).

[0157] Figure 29 is a perspective view of the bucket from the front (with the first lid closed). Figure 30 is a perspective view of the bucket from the rear (with the first lid closed and the second lid removed). Figure 31 is a perspective view of the bucket from the rear (with the first lid open and the second lid removed). Figure 32 is a perspective view of the bucket from the rear (with the first lid closed and the second lid attached).

[0158] Figure 33 is a cross-sectional view showing the workpiece retrieval device in the area enclosed by the dashed line XXXIII in Figure 27. Figure 34 is a cross-sectional view showing the workpiece retrieval device in the area enclosed by the dashed line XXXIV in Figure 28.

[0159] (Embodiment 3) In this embodiment, the structure of the workpiece recovery device 400 will be described. Referring to Figures 25 to 28, the workpiece recovery device 400 (device body 420) further has a cylindrical cover 426. The cylindrical cover 426 has a cylindrical shape extending in the Z-axis direction. The cylindrical cover 426 is connected to the side cover 18. The cylindrical cover 426 communicates with the first internal space 350 inside the cover body 310. The cylindrical cover 426 covers the horizontal column 289 extending from the side cover 18 (see Figures 7 to 9).

[0160] The workpiece transport mechanism 410 is located below the cylindrical cover 426. The workpiece transport mechanism 410 transports the workpieces that have been transported outside the machine tool 100 by the workpiece transport mechanism 210 shown in Figures 7 to 9 toward the front of the machine tool 100. The direction of workpiece transport by the workpiece transport mechanism 410 and the direction of workpiece transport by the workpiece transport mechanism 210 are perpendicular to each other.

[0161] As shown in Figures 27 and 28, the workpiece transport mechanism 410 includes a rotating roller 411 and a rotating roller 412, and a belt 416. The rotating roller 411 is rotatable about a rotational axis 406 extending in the Z-axis direction. The rotating roller 412 is rotatable about a rotational axis 407 extending in the Z-axis direction. Either the rotating roller 411 or the rotating roller 412 is a driven roller driven by a motor (not shown). The other rotating roller 411 or the rotating roller 412 is a driven roller that rotates when rotational motion from either the rotating roller 411 or the rotating roller 412 is transmitted via the belt 416.

[0162] The rotating rollers 411 and 412 are spaced apart from each other in the front-rear direction of the machine tool 100. The belt 416 is an annular strip and is stretched over the rotating rollers 411 and 412. The arm 251 slides directly above the belt 416 along a first direction 101 that is oblique to the vertical direction. The top surface 416a of the belt 416 faces the hand 261 in the vertical direction. The workpiece gripped by the hand 261 is placed on the top surface 416a of the belt 416.

[0163] The workpiece recovery device 400 (device body 420) further comprises a first cover 413 and a second cover 421. The first cover 413 covers the workpiece transport mechanism 410 below the cylindrical cover 426. The second cover 421 covers the space between the first cover 413 and the cylindrical cover 426. The second cover 421 protrudes further forward of the machine tool 100 than the cylindrical cover 426. Together with the first cover 413 and the cylindrical cover 426, the second cover 421 forms an internal space 430.

[0164] The internal space 430 is the space through which the workpiece is transported by the workpiece transport mechanism 210 and the workpiece transport mechanism 410. The internal space 430 houses the arm 251 and hand 261 of the workpiece transport mechanism 210, and the rotating roller 411, rotating roller 412, and belt 416 of the workpiece transport mechanism 410.

[0165] The second cover 421 is provided with a workpiece discharge port 429. The workpiece discharge port 429 opens facing the front of the machine tool 100. The opening surface of the workpiece discharge port 429 faces the workpiece transport mechanism 410 in the front-to-back direction of the machine tool 100. The workpiece discharge port 429 is an opening for allowing workpieces transported by the workpiece transport mechanism 410 to exit the internal space 430.

[0166] The bucket mounting base 427 is located in front of the machine tool 100 relative to the first cover 413 and the second cover 421. The top surface 416a of the belt 416 is positioned higher than the mounting surface 427a of the bucket mounting base 427. The workpiece discharge port 429 opens at a position higher than the mounting surface 427a of the bucket mounting base 427.

[0167] Referring to Figures 25 to 31, the bucket 460 is configured to accommodate workpieces. The bucket 460 is detachably mounted to the main body 420 of the apparatus. The bucket 460 is mounted to the main body 420 by being placed on the bucket mounting base 427.

[0168] As shown in Figures 27 to 31, the bucket 460 has a bucket body 470. The bucket body 470 forms a workpiece storage space 500 for accommodating workpieces. The bucket body 470 consists of a bottomed box body including a first side portion 471, a second side portion 472, a third side portion 473, a bottom portion 474, and a crossbar portion 475.

[0169] The bottom portion 474 constitutes the bottom of the bucket body 470. In a top view, the bottom portion 474 has a substantially rectangular shape. The first side portion 471, the second side portion 472, and the third side portion 473 rise from the periphery of the bottom portion 474. The first side portion 471 and the second side portion 472 face each other horizontally, with the workpiece storage space 500 in between. Handles 481 are attached to the first side portion 471 and the second side portion 472. The third side portion 473 extends between the first side portion 471 and the second side portion 472.

[0170] The workpiece storage space 500 is formed on the bottom portion 474 and is surrounded on three sides by the first side portion 471, the second side portion 472, and the third side portion 473.

[0171] The horizontal bar portion 475 faces the bottom portion 474 in the vertical direction, with the workpiece storage space 500 in between. The horizontal bar portion 475 extends between the first side portion 471 and the second side portion 472. In a top view, the horizontal bar portion 475 extends in a band shape between the first side portion 471 and the second side portion 472, while having a constant width.

[0172] The bucket body 470 has a first opening 491, a second opening 492, and a third opening 493. The workpiece storage space 500 is in communication with the space outside the bucket body 470 through the first opening 491, the second opening 492, and the third opening 493.

[0173] The first opening 491 opens upward. The opening surface formed by the first opening 491 is a horizontal plane. The opening surface formed by the first opening 491 faces the bottom 474 in the vertical direction. The first opening 491 is composed of the upper end of the first side portion 471, the upper end of the second side portion 472, the upper end of the third side portion 473, and the front end of the crossbar portion 475 (the front end of the machine tool 100 when the bucket 460 is placed on the bucket mounting base 427). The upper end of the third side portion 473 and the front end of the crossbar portion 475 face each other in the horizontal direction, with the opening surface formed by the first opening 491 in between.

[0174] The opening surface formed by the first opening 491 is smaller than the area of ​​the bottom portion 474 in a top view. The opening surface formed by the first opening 491 is larger than the area of ​​the horizontal bar portion 475 in a top view.

[0175] The second opening 492 opens in a horizontal direction. The opening surface formed by the second opening 492 is a vertical surface. In the horizontal direction, the opening surface formed by the second opening 492 faces the third side portion 473 across the workpiece storage space 500. The second opening 492 is composed of the rear end of the bottom portion 474 (the rear end of the machine tool 100 when the bucket 460 is placed on the bucket mounting base 427), the rear end of the first side portion 471, and the rear end of the second side portion 472.

[0176] The third opening 493 opens horizontally. The opening surface formed by the third opening 493 is a vertical surface. The third opening 493 is composed of the rear end of the first side portion 471, the rear end of the second side portion 472, and the rear end of the crossbar portion 475. The opening surface formed by the third opening 493 and the opening surface formed by the second opening 492 are aligned in the vertical direction. The opening surface formed by the third opening 493 is connected to the upper edge of the opening surface formed by the second opening 492.

[0177] The bucket 460 further comprises a first lid 480. The first lid 480 is rotatably mounted to the bucket body 470. The first lid 480 is attached to the rear end of the crossbar 475 via a plurality of hinges 482. The first lid 480 is attached to the bucket body 470 in a manner that prevents it from being detached. The first lid 480 is rotatably mounted to the crossbar 475 about a pivot axis 401. The pivot axis 401 extends horizontally.

[0178] The first cover 480 is made of a plate material and has a plan view corresponding to the opening surface formed by the first opening 491. The first cover 480 can operate between a closed state 480A (the state of the first cover 480 shown in Figures 27, 29, and 30) that closes the first opening 491 and an open state 480B (the state of the first cover 480 shown in Figures 28 and 31) that opens the first opening 491.

[0179] The first cover 480 has a rear end portion 480r. The rear end portion 480r is located on the rear side of the machine tool 100 relative to the pivot axis 401. As shown in Figures 29 and 30, when the first cover 480 is in the closed state 480A, the rear end portion 480r is superimposed on the crossbar portion 475 from the side of the workpiece storage space 500. As shown in Figure 31, when the first cover 480 is in the open state 480B, the rear end portion 480r is spaced apart from the crossbar portion 475 and positioned in the workpiece storage space 500.

[0180] As shown in Figures 27 and 28, when the bucket 460 is placed on the bucket mounting base 427, the bottom 474 faces the mounting surface 427a in the vertical direction. The opening surface of the second opening 492 faces the opening surface of the workpiece discharge port 429 in the horizontal direction. A gap is provided between the second cover 421 and the bucket body 470 (crossbar portion 475) that is small enough to prevent an operator's hand from entering. The second opening 492 forms a transport path for workpieces from the workpiece transport mechanism 410. Workpieces from the workpiece transport mechanism 410 enter the workpiece storage space 500 by passing through the workpiece discharge port 429 and the second opening 492 in sequence.

[0181] The workpiece retrieval device 400 (device body 420) further includes a plate member 431. The plate member 431 is provided across the internal space 430 and the workpiece storage space 500. The plate member 431 enters the workpiece storage space 500 from the internal space 430 through the workpiece discharge port 429 and the second opening 492.

[0182] The plate member 431 extends diagonally downward from the workpiece transport mechanism 410 toward the bucket body 470. The plate member 431 has a plate bottom portion 432 and a plate side portion 433. The plate bottom portion 432 is located on the extension of the top surface 416a of the belt 416. The plate bottom portion 432 extends so as it moves away from the top surface 416a of the belt 416 and approaches the bucket body 470, it shifts downward. Workpieces fed from the belt 416 roll or slide on the plate bottom portion 432 and move toward the workpiece storage space 500. The plate side portion 433 is arranged parallel to the vertical plane. The plate side portion 433 rises from the edge of the plate bottom portion 432.

[0183] The workpiece recovery device 400 (device body 420) further includes a support member 422 and a tilt adjustment mechanism 490. The support member 422 supports the plate member 431. The tilt adjustment mechanism 490 is provided on the plate member 431 and the support member 422. The tilt adjustment mechanism 490 can adjust the tilt of the plate member 431.

[0184] The support member 422 is attached to the second cover 421. The support member 422 consists of a plate member arranged parallel to the vertical plane. The support member 422 is provided across the internal space 430 and the workpiece storage space 500. The support member 422 enters the workpiece storage space 500 from the internal space 430 through the workpiece exit 429 and the second opening 492. The support member 422 is positioned opposite the plate side portion 433.

[0185] The tilt adjustment mechanism 490 includes an elongated hole 423 and a bolt 434. The elongated hole 423 is provided in the support member 422. The elongated hole 423 is a through-hole that penetrates the support member 422 and extends in an arc shape. The plate member 431 is supported by the support member 422 by inserting the bolt 434 into a hole provided in the plate member 431 (plate side portion 433) and the elongated hole 423, and fastening it with a nut (not shown). In this case, the tilt of the plate member 431 is adjusted by rotating the plate side portion 433 while shifting the insertion position of the bolt 434 relative to the elongated hole 423.

[0186] As shown in Figures 27 to 34, the workpiece recovery device 400 further includes a sensor 441. The sensor 441 is attached to at least one of the device body 420 and the first lid 480. The sensor 441 is capable of sensing the open / closed state of the first lid 480 and the mounting state of the bucket 460 to the device body 420.

[0187] The sensor 441 is attached to the main body 420 and the first lid 480. The sensor 441 has a sensor body portion 443 and a detection target portion 442. The sensor body portion 443 is the main body of the sensor 441 that can sense the open / closed state of the first lid 480 and the mounting state of the bucket 460 to the main body 420. The detection target portion 442 is the object to be detected by the sensor body portion 443.

[0188] The sensor body 443 is attached to the device body 420. The detection target unit 442 is attached to the first cover 480. The detection target unit 442 is detected by the sensor body 443 when the detection target unit 442 is positioned opposite the sensor body 443.

[0189] Sensor 441 is a non-contact safety switch. In this case, the detection target unit 442 is a signal transmitting unit that emits a signal, and the sensor body unit 443 is a sensor head that detects the detection target unit 442 by receiving a signal from the signal transmitting unit which is positioned opposite it. The detection target unit 442 has a first surface 442a. The detection target unit 442 emits a signal through the first surface 442a. The sensor body unit 443 has a second surface 443a. The sensor body unit 443 receives a signal from the detection target unit 442 through the second surface 443a.

[0190] The sensor body 443 is attached to the second cover 421. The sensor body 443 is mounted in a position where the second surface 443a is a vertical surface. The sensor body 443 is positioned above the plate member 431. The sensor body 443 is provided at the opening edge of the workpiece discharge port 429. The second cover 421 is provided with a notch 421h. The notch 421h forms a notch shape at the opening edge of the workpiece discharge port 429. The second surface 443a is exposed to the space outside the internal space 430 through the notch formed by the notch 421h.

[0191] The detection target unit 442 is attached to the rear end portion 480r of the first cover 480. The detection target unit 442 is attached to the inner surface of the first cover 480 that faces the workpiece storage space 500 when the first cover 480 is in the closed state 480A. The sensor 441 (detection target unit 442) faces the opening surface formed by the third opening 493 when the first cover 480 is in the closed state 480A. The first surface 442a is arranged parallel to the vertical plane when the first cover 480 is in the closed state 480A. The first surface 442a is exposed to the space outside the workpiece storage space 500 through the opening formed by the third opening 493 when the first cover 480 is in the closed state 480A. The sensor 441 (detection target unit 442) moves away from the opening surface formed by the third opening 493 when the first cover 480 is in the open state 480B. The first surface 442a is positioned non-parallel to the vertical plane when the first cover 480 is in the open state 480B. As the first cover 480 moves from the closed state 480A to the open state 480B, the first surface 442a moves away from the opening surface formed by the third opening 493.

[0192] As shown in Figures 25, 27, and 33, when the bucket 460 is mounted on the device body 420 and the first lid 480 is in the closed state 480A, the detection target part 442 faces the sensor body 443. The first surface 442a and the second surface 443a face each other with a gap between them. The distance between the first surface 442a and the second surface 443a is less than or equal to the detection distance at which the sensor body 443 can detect the detection target part 442. The detection distance is, for example, in the range of 10 mm to 20 mm. At this time, the sensor body 443 detects the detection target part 442. Sensor 441 senses that the bucket 460 is mounted on the device body 420 and senses that the first lid 480 is in the closed state 480A.

[0193] As shown in Figures 28 and 34, when the bucket 460 is attached to the device body 420 and the first lid 480 is in the open state 480B, the detection target part 442 moves away from the sensor body 443. The first surface 442a moves away from the second surface 443a as the first lid 480 moves from the closed state 480A to the open state 480B. The distance between the first surface 442a and the second surface 443a is greater than the detection distance at which the sensor body 443 can detect the detection target part 442. At this time, the sensor body 443 does not detect the detection target part 442. As shown in Figure 26, when the bucket 460 is removed from the device body 420, the detection target part 442 moves away from the sensor body 443. The sensor body 443 does not detect the detection target part 442.

[0194] In these cases, the sensor 441 senses that the first lid 480 is in the open state 480B, or that the bucket 460 has been removed from the main body 420 of the device.

[0195] As shown in Figures 33 and 34, the sensor 441 (sensor body 443) outputs the sensed open / closed state of the first lid 480 and the state in which the bucket 460 is attached to the device body 420 to the control device 160 of the machine tool 100. The control device 160 may perform control to stop the workpiece transport mechanism 210 and the workpiece transport mechanism 410 when the first lid 480 is in the open state 480B or the bucket 460 is detached from the device body 420, or it may perform control to notify the operator of such facts.

[0196] This configuration prevents workers from accessing the workpiece transport mechanism 410 through the workpiece transport port 429 when the distance from the workpiece transport port 429 to the workpiece transport mechanism 410 is short, or when the height difference between the workpiece transport port 429 and the bucket 460 is small. Furthermore, shortening the distance from the workpiece transport port 429 to the workpiece transport mechanism 410 improves the maintainability of the workpiece transport mechanism 410.

[0197] Referring to Figure 32, the bucket 460 further has a second lid 496. The second lid 496 is made of plate material. The second lid 496 is detachably attached to the bucket body 470. When the second lid 496 is attached to the bucket body 470, it closes the second opening 492.

[0198] The bucket body 470 further has a folded portion 497. The folded portion 497 is formed by folding the rear ends of the first side portion 471, the second side portion 472, and the bottom portion 474 back by 90° toward the workpiece storage space 500. The folded portion 497 extends in a frame-like manner along the rear ends of the first side portion 471, the second side portion 472, and the bottom portion 474. The second opening 492 opens inside the inner periphery of the folded portion 497. The second lid 496 is inserted inside the folded portion 497.

[0199] The second cover 496 is removed from the bucket body 470 when the bucket 460 is attached to the device body 420. This opens the second opening 492, allowing workpieces to enter the bucket 460 from the workpiece transport mechanism 410. The second cover 496 is attached to the bucket body 470 when the bucket 460 is removed from the device body 420. This closes the second opening 492, allowing the bucket 460 containing the workpieces to be carried.

[0200] Referring to Figures 25 to 32, the configuration of the workpiece recovery device 400 and bucket 460 in Embodiment 3 of this invention is summarized.

[0201] The workpiece recovery device 400 in this embodiment includes a device body 420 having a workpiece transport mechanism 410, a bucket body 470 having a first opening 491 and accommodating workpieces transported by the workpiece transport mechanism 410, a bucket 460 attached to the bucket body 470 and having a first lid 480 that can operate between a closed state 480A that closes the first opening and an open state 480B that opens the first opening 491, and which is detachably mounted to the device body 420, and a sensor 441 attached to at least one of the device body 420 and the first lid 480, which is capable of sensing the open / closed state of the first lid 480 and the mounting state of the bucket 460 to the device body 420.

[0202] With this configuration, the open / closed state of the first lid 480 and the mounted state of the bucket 460 are sensed by a common sensor 441, so a workpiece recovery device 400 for collecting workpieces transported by the workpiece transport mechanism 410 into the bucket 460 can be realized with a simple configuration.

[0203] Furthermore, the first lid 480 is rotatably attached to the bucket body 470. The sensor 441 has a sensor body portion 443 attached to the device body 420, and a detection target portion 442 provided on the first lid 480 and detected by the sensor body portion 443 when positioned opposite to the sensor body portion 443. When the bucket 460 is mounted on the device body 420 and the first lid 480 is in the closed state 480A, the detection target portion 442 faces the sensor body portion 443. When the bucket 460 is mounted on the device body 420 and the first lid 480 is in the open state 480B, the detection target portion 442 separates from the sensor body portion 443. When the bucket 460 is removed from the device body 420, the detection target portion 442 separates from the sensor body portion 443.

[0204] With this configuration, when the bucket 460 is attached to the device body 420 and the first lid 480 is in the closed state 480A, the detection target unit 442 faces the sensor body 443. At this time, the sensor body 443 detects the detection target unit 442, allowing it to determine that the bucket 460 is in a normal state. Furthermore, when the bucket 460 is attached to the device body 420 and the first lid 480 is in the open state 480B, and when the bucket 460 is removed from the device body 420, the detection target unit 442 separates from the sensor body 443. At this time, the sensor body 443 does not detect the detection target unit 442, allowing it to determine that the bucket 460 is in an abnormal state.

[0205] For example, a non-contact safety switch may be used as the sensor 441. In this case, the detection target unit 442 is a signal transmitting unit that emits a signal, and the sensor body 443 is a sensor head that detects the detection target unit 442 by receiving a signal from the signal transmitting unit positioned opposite it. Another example is a photoelectric sensor. In this case, the detection target unit 442 is a light emitting unit that emits light, and the sensor body 443 is a light receiving unit that detects the detection target unit 442 by receiving light from the light emitting unit positioned opposite it. Yet another example is a proximity sensor. For example, when a proximity sensor is attached to the device body 420, the proximity sensor consists only of a sensor body that detects the first cover 480.

[0206] Furthermore, the bucket body 470 further includes a second opening 492 which forms a transport passage for workpieces from the workpiece transport mechanism 410. The bucket 460 is detachably attached to the bucket body 470 and further includes a second lid 496 which closes the second opening 492 when attached to the bucket body 470.

[0207] With this configuration, when the bucket 460 is attached to the device body 420, the second lid 496 is removed from the bucket body 470 and the second opening 492 is opened, allowing workpieces to be collected into the bucket 460 through the second opening 492. When the bucket 460 is removed from the device body 420, the second lid 496 is attached to the bucket body 470 and the second opening 492 is closed, allowing the bucket 460 containing the workpieces to be carried.

[0208] The main body of the device 420 further includes a plate member 431 extending diagonally downward from the workpiece transport mechanism 410 toward the bucket body 470, a support member 422 that supports the plate member 431, and a tilt adjustment mechanism 490 provided on the plate member 431 and the support member 422 that can adjust the tilt of the plate member 431.

[0209] With this configuration, the workpiece can be smoothly moved from the workpiece transport mechanism 210 toward the bucket body 470 by adjusting the inclination of the plate member 431 according to the weight or shape of the workpiece.

[0210] In this embodiment, the bucket 460 is detachably attached to the main body 420 of the apparatus having a workpiece transport mechanism 410, and is a bucket for collecting workpieces transported by the workpiece transport mechanism 410. The bucket 460 has a first opening 491 that opens upward, a second opening 492 that opens horizontally and forms a transport path for workpieces from the workpiece transport mechanism 410, and a third opening 493 that opens horizontally and is connected to the upper edge of the opening surface formed by the second opening 492, and a bucket body 470 that contains workpieces, and a bucket body 480A that is rotatably attached to the bucket body 470 and has a closed state 480A that closes the first opening 491 and an open state 48 that opens the first opening 491 The system includes a first lid 480 that can operate between 0B and 0B, a second lid 496 that is detachably attached to the bucket body 470 and closes the second opening 492 when attached to the bucket body 470, and a sensor 441 (detection target part 442) that is attached to the first lid 480 and faces the opening surface of the third opening 493 when the first lid 480 is in the closed state 480A, and moves away from the opening surface of the third opening 493 when the first lid 480 is in the open state 480B.

[0211] With this configuration, the open / closed state of the first lid 480 and the mounted state of the bucket 460 are sensed by a common sensor 441, so that the bucket 460 for collecting workpieces transported by the workpiece transport mechanism 410 can be realized with a simple configuration.

[0212] The machine tool 100 in this embodiment includes a cover body 12 that demarcates the processing area 150, and a workpiece recovery device 400 for recovering processed workpieces that have been discharged from the processing area 150.

[0213] [Notes concerning workpiece transfer device and workpiece recovery device] (1) The workpiece transfer device is required to be retrofittable to a machine tool and to be mounted on the machine tool without changing the machine size (cover line) of the machine tool. The workpiece transfer device described herein has the following features.

[0214] (a) A workpiece transfer device (workpiece unloader) is mounted in the space between the front cover and the tool post of the machine tool, above the opposing workpiece spindle. The workpiece transfer device lifts the processed workpiece from the opposing workpiece spindle and then moves it in the Z-axis direction to transport it outside the machine tool.

[0215] (b) A combination of a double-speed mechanism and a ball screw is used as the mechanism for stroking the workpiece up and down. This allows for a compact workpiece transport device in the vertical direction. A servo motor, which is the power source for the ball screw, is arranged via a timing belt. A mechanism is also provided to detect belt breakage and prevent the workpiece from falling when the belt breaks. By using a timing belt, it is possible to arrange the ball screw and the servo motor in parallel. This allows for an even more compact workpiece transport device in the vertical direction.

[0216] (c) Servo motors are used for all axes as the power source in the workpiece transfer device. This allows the hand to be stopped at any position. The workpiece can be caught by the hand or released from the hand at any position. It is possible to accommodate differences in the size of the workpieces held by the opposing workpiece spindles. By positioning the hand directly above the belt conveyor outside the machine tool, it is possible to prevent excessive external force from being applied to the workpiece when it falls from the hand.

[0217] (d) The straight line connecting the center of the workpiece held by the opposing workpiece spindle (the rotation center of the opposing workpiece spindle) and the center of the workpiece gripped by the hand and transported to the raised position is inclined with respect to the vertical direction. That is, the direction of movement of the hand (the sliding direction of the arm) is oblique to the vertical direction. The inclination of the direction of movement of the hand with respect to the vertical direction is, for example, 8°. The inclination of the direction of movement of the hand with respect to the vertical direction may be in the range of 3° to 15° or in the range of 5° to 10°. This makes it possible to avoid interference between the movement range of the hand as it moves up and down and the tool post. Since it is not necessary to change the cover line of the cover that covers the tool post base, the specifications of the X-axis stroke and Y-axis stroke of the tool post can be maintained.

[0218] (e) The work unloader cover consists of a cylindrical cover body extending in the Z-axis direction and a door attached to the cover body that can be opened and closed. Closing the door separates the inside of the cover from the machining area. Various pipes and wires from the opposing work spindle are routed between the work unloader cover and the front cover. The wires and pipes are suspended from the ceiling cover located above the opposing work spindle. There are no changes to the front cover and ceiling cover between the standard specification and the special specification with the added work unloader.

[0219] (f) In order to secure space for routing piping and wiring between the work unloader cover and the front cover, the cover line of the work unloader cover on the side facing the front cover is positioned close to the tool post side. In this configuration, by making the direction of movement of the hand (the sliding direction of the arm) oblique to the vertical direction, a space is created inside the work unloader cover, near the lower end on the side facing the front cover. The door opening and closing drive mechanism (piston cylinder) and the door open state detection mechanism (limit switch and dog) are installed in this space.

[0220] (g) The main body of the work unloader cover is provided with a pocket that protrudes toward the front cover. When the door is closed, the limit switch dog is housed in this pocket. Space for routing piping and wiring is provided in a recessed position within the pocket. The door of the work unloader cover is provided with a recess to avoid interference between the tool, which moves circumferentially with the rotation of the tool post, and the door.

[0221] (h) The door of the work unloader cover is rotatable. The door opens towards the operator. When viewed in the front-to-back direction of the machine tool, the open door of the work unloader cover and the window of the front door of the machine tool may partially overlap.

[0222] (i) A sensor (for example, a non-contact safety switch described later) is provided separately to detect the closed state of the work unloader cover door. If the limit switch detects that the door is open and the non-contact safety switch does not detect that the door is closed, it is determined that the door is open. At this time, control is executed to prevent the front door of the machine tool from being opened. If the limit switch does not detect that the door is open and the non-contact safety switch detects that the door is closed, it is determined that the door is closed. At this time, the servo motor for moving the hand in the Z-axis direction is not driven, and the entire machine tool is stopped.

[0223] (2) Workpiece recovery devices are known that collect workpieces transported by a workpiece transport mechanism such as a belt conveyor into a bucket. The bucket is detachable from the main body of the device which has the belt conveyor in order to transport the workpieces collected in the bucket. In such a workpiece recovery device, it is necessary to prevent workers from accessing the workpiece transport path.

[0224] The size and dimensions of the workpieces being transported vary, and it is difficult to increase the height difference between the bucket and the conveyor belt to prevent damage to the workpieces during transport. Another idea is to install a hinged door at the workpiece exit from the conveyor belt. However, workers can easily grab and open the door, and in the case of lightweight workpieces, there is the problem that the workpieces being transported from the conveyor belt cannot push the door open.

[0225] The workpiece retrieval device described herein has the following features: (a) A lid is provided to prevent an operator's hand from entering the bucket, and a sensor is provided on the lid. When the lid is opened, the sensor turns OFF, and the open state of the lid is detected. Even when the bucket is removed from the device body, the sensor turns OFF, and the removed state of the bucket is detected. This allows an abnormal state in which the workpiece discharge port becomes accessible to be detected by a single sensor. When the sensor detects an abnormal state, workpiece unloading is stopped.

[0226] (b) As a sensor, for example, a non-contact safety switch is used in which a signal transmitter attached to the lid and a sensor head attached to the cover are installed without direct contact (the detection distance is, for example, in the range of 10 mm to 20 mm). When the signal transmitter is positioned opposite the sensor head, the sensor head detects the signal from the signal transmitter and transmits the signal as information about the closed state of the lid and the installed state of the bucket.

[0227] (c) A single sensor can detect the presence or absence of a bucket and the opening and closing of the bucket lid, thereby enhancing the safety of the workpiece retrieval device. The safety switch is less expensive than area sensors, etc. When the distance from the workpiece exit to the workpiece discharge mechanism such as a belt conveyor is short, and / or when the height difference between the workpiece exit and the bucket is small, it is possible to prevent workers from accessing the workpiece discharge mechanism. By shortening the distance from the workpiece exit to the workpiece discharge mechanism such as a belt conveyor, the maintainability of the workpiece discharge mechanism can be improved. The workpiece retrieval device can be applied regardless of the size of the workpiece. By opening the lid, the workpieces collected in the bucket can be checked without removing the bucket from the device body.

[0228] (d) A plate member whose inclination (for example, in an angular range of 5° to 15°) can be adjusted may be placed between the belt conveyor and the bucket. The inclination of the plate member can be adjusted steplessly by making the fastening holes of the plate member elongated in an arc shape.

[0229] (e) An opening is provided on the rear side of the bucket, which forms a transport path for workpieces from the workpiece transport mechanism. When the bucket is removed from the main body of the device and the workpieces collected in the bucket are to be carried, a lid is attached to the bucket to close the opening. When the bucket is attached to the main body of the device, the lid is removed from the bucket.

[0230] The embodiments disclosed herein should be considered in all respects to be illustrative and not restrictive. The scope of the invention is indicated by the claims rather than the foregoing description, and all modifications within the meaning and scope of equivalents of the claims are intended.

[0231] This application is based on Japanese Patent Application No. 2024-192866, filed with the Japan Patent Office on 1 November 2024, and Japanese Patent Application No. 2025-093818, filed with the Japan Patent Office on 5 June 2025, the entire contents of which are incorporated herein by reference.

[0232] 12, 310 Cover body, 12h, 316 Opening, 13 Front door, 14 Window, 15 Front cover, 16 Control panel, 17 Ceiling cover, 18 Side cover, 20 Second work spindle, 21 Gripping claw, 30 Tool post, 31 Saddle, 32 Horizontal feed table, 33 Base, 36 Swivel body, 37 Mounting section, 38 Tool holder, 39 Tool post base, 40 Tool post cover, 100 Machine tool, 101 First direction, 102 Second direction, 103 Third direction, 106 Up and down direction, 110 Swivel center axis, 120 Rotation center axis, 140 Dotted line, 150 Machining area, 200 Work transport device, 201, 202, 203 Rotation center axis, 210, 410 Work transport mechanism, 221 First servo motor, 226 1st pulley, 227 2nd pulley, 231 Ball screw, 232 Screw, 233 Nut, 236 Angle, 240 Speed-doubling mechanism, 241 Intermediate member, 243 Pinion, 244, 245 Guide mechanism, 246 1st rack, 247 2nd rack, 251 Arm, 261 Hand, 270 Transmission mechanism, 271 Timing belt, 272 2nd rotating body, 272A 1st state, 272B 2nd state, 273 1st rotating body, 274 1st locking part, 275 Shaft part, 276, 441 Sensor, 277 2nd locking part, 278 Elastic member, 281 Traveling body, 286 2nd servo motor, 287 Feed mechanism, 288 Guide mechanism, 289 Cross column, 301 Rotation center axis, 302 Maximum range, 306, 307 Rotational axis, 310f Front section, 311 Top surface, 312 Bottom surface, 317 Upper opening, 318 Cover side opening, 320 Door, 320A, 480A Closed state, 320B, 480B Open state, 321 Main surface, 322 Recess, 330 Line body, 341 Cover body section, 342 Protruding part, 346 Gap (second gap), 347 First gap, 350 First internal space, 360 Second internal space, 371 Dog, 372 Switch, 372p Operating section, 376 Angle, 381 Piston cylinder, 382 Rod, 383 Cylinder body, 391 Sensor, 400 Workpiece recovery device, 401 Rotational axis, 406,407 Rotating central axis, 411 Rotating shaft, 412 Rotating shaft, 413 First cover, 416 Belt, 416a Top surface, 420 Device body, 421 Second cover, 421h Notch, 422 Support member, 423 Elongated hole, 426 Cylinder cover, 427 Bucket mounting base, 427a Mounting surface, 429 Workpiece discharge port, 430 Internal space, 431 Plate member, 432 Plate bottom, 433 Plate side, 434 Bolt, 442 Detection target part, 442a First surface, 443 Sensor body part, 443a Second surface, 460 Bucket, 470 Bucket body, 471 First side, 472 Second side, 473 Third side, 474 Bottom, 475 Crossbar part, 480 First lid, 480r rear end, 481 handle, 482 hinge, 490 tilt adjustment mechanism, 491 first opening, 492 second opening, 493 third opening, 496 second lid, 497 folded part, 500 workpiece storage space, T tool, W workpiece, α angle.

Claims

1. A workpiece recovery device comprising: a device body having a workpiece transport mechanism; a bucket body having a first opening and containing workpieces transported by the workpiece transport mechanism; a bucket attached to the bucket body and having a first lid that can operate between a closed state that closes the first opening and an open state that opens the first opening, and which is detachably mounted to the device body; and a sensor attached to at least one of the device body and the first lid, which is capable of sensing the open / closed state of the first lid and is capable of sensing the mounting state of the bucket to the device body.

2. The workpiece recovery device according to claim 1, wherein the first lid is rotatably mounted on the bucket body, the sensor has a sensor body portion attached to the device body, and a detection target portion provided on the first lid and detected by the sensor body portion when positioned opposite to the sensor body portion, the detection target portion faces the sensor body portion when the bucket is mounted on the device body and the first lid is in the closed state, the detection target portion separates from the sensor body portion when the bucket is mounted on the device body and the first lid is in the open state, and the detection target portion separates from the sensor body portion when the bucket is removed from the device body.

3. The workpiece recovery device according to claim 1 or 2, wherein the bucket body further includes a second opening that forms a transport passage for workpieces from the workpiece transport mechanism, and the bucket further has a second lid that is detachably attached to the bucket body and closes the second opening when attached to the bucket body.

4. The workpiece recovery device according to claim 1 or 2, wherein the device body further comprises a plate member extending diagonally downward from the workpiece transport mechanism toward the bucket body, a support member supporting the plate member, and a tilt adjustment mechanism provided on the plate member and the support member, which is capable of adjusting the tilt of the plate member.

5. A bucket for collecting workpieces transported by a workpiece transport mechanism, which is detachably attached to the main body of a device having a workpiece transport mechanism, comprising: a bucket body for accommodating workpieces, having a first opening that opens upward, a second opening that opens horizontally and forms a transport path for workpieces from the workpiece transport mechanism, and a third opening that opens horizontally and is connected to the upper edge of the opening surface formed by the second opening; a first lid that is rotatably attached to the bucket body and is capable of operating between a closed state that closes the first opening and an open state that opens the first opening; a second lid that is detachably attached to the bucket body and closes the second opening when attached to the bucket body; and a sensor that is attached to the first lid and faces the opening surface formed by the third opening when the first lid is in the closed state, and moves away from the opening surface formed by the third opening when the first lid is in the open state.

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