Workpiece conveying device

Abstract

It is a subject to provide a workpiece conveying device capable of linearly conveying a workpiece with a light-weight and simple configuration. The present invention is a workpiece conveying device 100 for conveying a workpiece W, the workpiece conveying device 100 comprising a main body portion 10; a rail portion 1 mounted to an upper portion of the main body portion 10; a guide portion 1a slidable along the rail portion 1; an arm 3 in which a first pivotally attaching portion 3b at the upper end thereof is pivotally attached to the guide portion 1a; a holding means 4 which is mounted to a second shall 3a at a lower end of the arm 3 and which can hold the workpiece W; an auxiliary arm 20 mounted to a first shaft 2b of the main body portion 10 to be rotatable; a slider portion 2a slidable along the auxiliary arm 20; and servomotors for driving the auxiliary arm 20, wherein a second pivotally attaching portion 3c at approximately a center of the arm 3 is pivotally attached to the slider portion 2a.

Claims

1. A workpiece conveying device for conveying a workpiece, comprising: a main body portion; a rail portion provided to extend at an upper portion of the main body portion; a guide portion slidable along the rail portion; an arm which upper end is pivotally attached to the guide portion by a first pivotally attaching portion; a holding means which is mounted to an arm lower-end shaft at a lower end of the arm and which can hold the workpiece; an auxiliary arm mounted to a main body shaft of the main body portion to be rotatable; and a slider portion slidable along the auxiliary arm, wherein the arm is a single arm, and approximately middle of the arm is pivotally mounted to the slider portion by a second pivotally attaching portion, the second pivotally attaching portion is provided closer to the first pivotally attaching portion side than a center position with respect to a longitudinal direction of the arm, the slider portion is attached to the auxiliary arm via a sliding belt portion, and rotation of the auxiliary arm, rotation of the holding means, and sliding of the slider portion are performed by driving a first servo motor, a second servo motor, and a third servo motor, respectively.

2. The workpiece conveying device according to claim 1, wherein a ratio of a distance from the first pivotally attaching portion to the second pivotally attaching portion and a distance from the arm lower-end shaft to the second pivotally attaching portion is 1:1.2 to 2.

3. The workpiece conveying device according to claim 1, wherein a ratio of a distance from the main body shaft to the second pivotally attaching portion and a distance from the first pivotally attaching portion to the arm lower-end shaft is 1:2 to 4.

4. The workpiece conveying device according to claim 1, wherein the holding means is comprised of a crossbar connected to the arm and suction portions mounted to the crossbar.

5. The workpiece conveying device according to claim 1 which is used as a device carrying a workpiece in and out with respect to a press machine and which is mounted to a post of the press machine.

Description

BRIEF DESCRIPTION OF DRAWINGS

(1) FIG. 1 is a front view showing one example of a workpiece conveying device according to the present embodiment.

(2) FIG. 2 is a side view showing one ample of a workpiece conveying device according to the present embodiment.

(3) FIG. 3 is a schematic top view showing a holding means in the workpiece conveying device according to the present embodiment.

(4) FIG. 4 is an enlarged front view showing an auxiliary arm in the workpiece conveying device according to the present embodiment.

(5) FIG. 5 is a schematic perspective view showing a press machine to which the workpiece conveying device according to the present embodiment is mounted.

(6) FIG. 6(a) is an explanatory view for explaining a track of a second shaft at a lower end of an arm when a workpiece is conveyed using the workpiece conveying device according to the present embodiment.

(7) FIG. 6(b) is an explanatory view for explaining a track of the second shaft at the lower end of an arm when a workpiece is conveyed using the workpiece conveying device according to the present embodiment.

(8) FIG. 6(c) is an explanatory view for explaining a track of the second shaft at the lower end of an arm when a workpiece is conveyed using the workpiece conveying device according to the present embodiment.

(9) FIG. 6(d) is an explanatory view for explaining a track of the second shaft at the lower end of an arm when a workpiece is conveyed using the workpiece conveying device according to the present embodiment.

(10) FIG. 6(e) is an explanatory view for explaining a track of the second shaft at the lower end of an arm when a workpiece is conveyed using the workpiece conveying device according to the present embodiment.

(11) FIG. 6(f) is an explanatory view for explaining a track of the second shaft at the lower end of an arm when a workpiece is conveyed using the workpiece conveying device according to the present embodiment.

DESCRIPTION OF EMBODIMENTS

(12) Preferred embodiments of the present invention will be explained in details hereinbelow with reference to drawings as necessary. In this respect, identical elements are marked with identical reference signs, and duplicated explanations will be omitted. Further, unless specified otherwise, positional relationships of top and bottom or right and left are based on the positional relationships as shown in the drawings. Moreover, dimensional ratios of the drawings are not limited to the illustrated ratios.

(13) FIG. 1 is a front view showing one example of a workpiece conveying device according to the present embodiment.

(14) As shown in FIG. 1, the workpiece conveying device 100 according to the present embodiment comprises a main body portion 10; a rail portion 1 provided to extend at an upper portion of the main body portion 10; a guide portion 1a slidable along the rail portion 1; an arm 3 which upper end is pivotally attached to the guide portion 1a by means of a first pivotally attaching portion 3b; a holding means 4 which is mounted to a second shaft 3a at a lower end of the arm 3 and which can hold a workpiece W; an auxiliary arm 20 mounted to a first shaft 2b of the main body portion 10 to be rotatable; and a slider portion 2a slidable along the auxiliary arm 20.

(15) The slider portion 2a is pivotally attached to approximately the center of the arm 3 by means of a second pivotally attaching portion 3c.

(16) In this manner, the workpiece conveying device 100 is of light-weight and simple configuration.

(17) In the workpiece conveying device 100, the workpiece W is conveyed by holding the workpiece W by means of the holding means 4 and by rotating the arm 3 to which the holding means 4 is mounted at the first pivotally attaching portion 3b.

(18) At this time, the guide portion in pivotally attached to the arm 3 by means of the first pivotally attaching portion 3b slides along the rail portion 1 in the vertical direction, and simultaneously therewith, the slider portion 2a pivotally attached to approximately the center of the arm 3 by means of the second pivotally attaching portion 3c slides in the longitudinal direction of the auxiliary arm 20. In this respect, details of these movements will be described later. With this arrangement, it is possible to reliably hold the workpiece W while the workpiece W can be conveyed linearly with a compact configuration.

(19) The workpiece conveying device 100 will hereinafter be explained in further details.

(20) In the workpiece conveying device 100, the rail portion 1 extending linearly in the longitudinal direction (vertical direction) of the main body portion 10 is provided to extend at an upper portion of the main body portion 10, and the guide portion 1a is mounted to the rail portion 1 to be freely slidable in the vertical direction along the rail portion 1.

(21) The guide portion 1a is pivotally attached to the upper end of the arm 3 by means of the first pivotally attaching portion 3b.

(22) Accordingly, the upper end of the arm 3 slides in the vertical direction along the rail portion 1 integrally with the guide portion 1a. With this arrangement, it is possible to adjust heights of workpieces W at the time of conveying workpieces W.

(23) The auxiliary arm 20 is mounted to the main body portion 10 in a rotatable manner.

(24) Here, the auxiliary arm 20 is mounted to the main body portion 10 just below the rail portion 1 and being apart therefrom by a certain distance. With this arrangement, it is possible to make the auxiliary arm 20 more compact and to reduce the moving distance of the slider portion 2 at the time of conveying a workpiece. Namely, it is possible to make the slider portion 2a smoothly follow movements of the arm 3 while movements of the slider portion 2a itself are relatively limited.

(25) FIG. 2 is a side view showing one example of a workpiece conveying device according to the present embodiment.

(26) As shown in FIG. 2, in the workpiece conveying device 100, a servomotor (hereinafter referred to as “first servomotor” for the sake of convenience) 7a and a reduction gear 8a coupled to the first servomotor are mounted to the rear surface of the rail portion 1. Therefore, by suitably selecting reduction ratios, the first servomotor 7a can suppress torque of a motor shaft.

(27) Here, the auxiliary arm 20 rotates around the first shaft 2b provided at the main body portion 10. Further, the first servomotor 7a is coupled to the first shaft 2b via the reduction gear 8a. Therefore, the auxiliary arm 20 is arranged to rotate around the first shaft 2b of the main body portion 10 as indicated by arrow A based on driving of the first servomotor 7a.

(28) Returning to FIG. 1, the main body portion 10 is arranged to be mounted to a post of a press machine as it will be described later. Namely, the workpiece conveying device 100 can be mounted to a post P1 of a press machine via the main body portion 10 (see FIG. 5).

(29) The arm 3 is pivotally attached to the guide portion 1a at its upper end by means of the first pivotally attaching portion 3b and is made to rotate largely around the first pivotally attaching portion 3b.

(30) Further, approximately the center of the arm 3 is pivotally attached to the slider portion 2a by means of the second pivotally attaching portion 3c.

(31) Moreover, the holding means 4 capable of holding a workpiece W is mounted to the second shaft 3a at the lower end of the arm 3.

(32) Here, the second pivotally attaching portion 3c is provided to lean closer to the first pivotally attaching portion 3b side (guide portion 1a side) than the central portion with respect to the longitudinal direction of the arm 3. With this arrangement, the length of the auxiliary arm 20 can be reduced, and the device can be made more compact.

(33) At this time, it is preferable that the ratio of the distance H1 from the first pivotally attaching portion 3b to the second pivotally attaching portion 3c and the distance H2 from the second shaft 3a to the second pivotally attaching portion 3c (H1:H2) is 1:1.2 to 2. In this case, the device can be made more compact, and it is also possible to reduce energy costs necessary for conveyance.

(34) Further, it is preferable that the ratio of the distance H3 from the first shaft 2b to the second pivotally attaching portion 3c and the distance (H1+H2) from the first pivotally attaching portion 3b to the second shaft 3b (H3:H1+H2) is 1:2 to 4. In this case, the size of the device can be made more compact.

(35) The holding means 4 comprises the crossbar 4a coupled to the second shaft 3a at the lower end of the arm and a plurality of suction portions 4b mounted to the crossbar 4a. Therefore, it is possible to suck and hold a workpiece W also in case of a relatively large workpiece W.

(36) FIG. 3 is a top view showing the holding means in the workpiece conveying device according to the present embodiment.

(37) As shown in FIG. 3, the suction portions 4b each comprised of a pair of right and left vacuum cups are mounted at eight spots of the crossbar 4a in the holding means 4.

(38) Each of the suction portions 4b sucks and holds a planar portion of a workpiece W by sucking its interior. In this respect, it is also possible that each of the suction portions 4b sucks and holds the workpiece W independently from each other. In this case, it is possible to suitably select suction portions 4b to be used depending on shapes and sizes of workpieces W.

(39) In the holding means 4, a servomotor 7c (hereinafter referred to as “second servomotor” for the sake of convenience) is coupled to the second shaft 3a (see FIG. 2).

(40) Accordingly, the crossbar 4a is made to rotate based on driving of the second servomotor 7c. In this respect, the crossbar 4a rotates with the suction portions 4b continuously facing directly downward corresponding to the position of the rotating arm 3.

(41) FIG. 4 is an enlarged front view showing the auxiliary arm in the workpiece conveying device according to the present embodiment.

(42) As shown in FIG. 4, in the workpiece conveying device 100, the belt portion 2 which slides along the longitudinal direction of the auxiliary arm 20 is extended at the auxiliary arm 20, and the slider portion 2a is fixed at the belt portion 2.

(43) More specifically, at the auxiliary arm 20, the belt portion 2 is extended in the longitudinal direction via a follower pulley 9a and a drive pulley 9b, and the slider portion 2a is fixed to the belt portion 2.

(44) Further, a servomotor 7b (hereinafter referred to as “third servomotor” for the sake of convenience) for driving the follower pulley 9b is mounted to the auxiliary arm 20 via a reduction gear 8b. Therefore, by suitably selecting reduction ratios, the third servomotor 7b can suppress torque of the motor shaft.

(45) In the auxiliary arm 20, the drive pulley 9b moves based on driving of the third servomotor 7b, and the belt portion 2 slides along the longitudinal direction of the auxiliary arm 20.

(46) At this time, since the slider portion 2a is fixed to the belt portion 2, the slider portion 2a will also slide along the longitudinal direction of the auxiliary arm 20 integrally with the belt portion 2. In this respect, the arm 3 is pivotally attached to the slider portion 2a by means of the second pivotally attaching portion 3c as described above.

(47) In the workpiece conveying device 100, the arm 3 rotates at the first pivotally attaching portion 3b, through the cooperation of the first servomotor 7a for driving the auxiliary arm 20 and the third servomotor 7b for driving the slider portion 2a.

(48) In the workpiece conveying device 100, by sliding the slider portion 2a pivotally attached to the arm 3 along the auxiliary arm 20 mounted to the main body portion 10 in a rotatable manner, the auxiliary arm 20 supports the arm 3 via the slider portion 2a while it does not interfere linear conveyance of the workpiece W. With this arrangement, it is possible to linearly convey also a workpiece W of relatively large weight as it will be described later.

(49) In the workpiece conveying device 100, since all of rotation of the holding means 4, rotation of the auxiliary arm 20 and sliding of the slider portion 2a is performed by driving the servomotors as described above, the configuration does not require space and be even simpler.

(50) The workpiece conveying device 100 according to the present embodiment is preferably used, for instance, as a device for carrying a workpiece in and out with respect to a press machine and which is mounted to a post of the press machine.

(51) FIG. 5 is a schematic perspective view showing a press machine to which the workpiece conveying device according to the present embodiment is mounted. In this respect, detailed portions of the press machine will be omitted.

(52) As shown in FIG. 5, the press machine P is arranged in that the main body portion 10 of the workpiece conveying device 100 is mounted to a post P1. Namely, since the workpiece conveying device 100 according to the present embodiment is of light-weight and simple configuration and is space-saving, it can be installed in a small space.

(53) In the press machine P, a workpiece after pressing is carried out by the workpiece conveying device 100. In this respect, it is, of course, also possible to carry a workpiece in before pressing into the press machine.

(54) For instance, also in case a plurality of press machines P is aligned to comprise a tandem press line, the workpiece conveying devices 100 will not require large spaces and the entire line can be made compact.

(55) Moreover, as described above, since the workpiece conveying device 100 can convey a workpiece linearly, it is possible to carry the workpiece in and out quickly and efficiently in the press machine P.

(56) Next, a workpiece conveying method using the workpiece conveying device 100 will be explained.

(57) FIGS. 6(a) to FIG. 6(f) are explanatory views for explaining tracks of the lower end (base portion of the second shaft 3a) of the arm when a workpiece is conveyed using the workpiece conveying device according to the present embodiment. In this respect, detailed descriptions of the holding means 4 are omitted for the sake of convenience.

(58) As shown in FIG. 6(a), the lower end of the arm 3 holds a workpiece (not shown) at position A via the holding means. At this time, the guide portion 1a is positioned on the lowermost side of the rail portion 1 and the slider portion 2a is positioned closer to the upper side of the auxiliary arm 20.

(59) Then, the guide portion 1a is moved upward up to approximately the center of the rail portion 1 and the slider portion 2a is moved to the uppermost side of the auxiliary arm 20. Then, the arm 3 will move upward while maintaining a predetermined angle as shown in FIG. 6(b) and the lower end of the arm 3 reaches position B. With this arrangement, the workpiece (not shown) is lifted up.

(60) Next, the slider portion 2a maintains the state in which it is at the uppermost position of the auxiliary arm 20 and the guide portion 1a is moved to the uppermost side of the rail portion 1. Then, the arm 3 and the auxiliary arm 20 rotate to be aligned on the same line as shown in FIG. 6(c). Consequently, the lower end of the arm 3 moves rightward and reaches position C. At this time, the guide portion 1a, the rail portion 1, the slider portion 2a, the auxiliary arm 20 and the arm 3 will overlap on the same line.

(61) Next, the slider portion 2a maintains the state in which it is at the uppermost position of the auxiliary arm 20 and the guide portion 1a is moved downward up to approximately the center of the rail portion 1. Then, the arm 3 and the auxiliary arm 20 rotate as shown in FIG. 6(d) and the lower end of the arm 3 moves further rightward and reaches position D.

(62) Next, the guide portion 1a is moved to the lowermost side of the rail portion 1 and the slider portion 2a is moved to a position closer to the upper side of the auxiliary arm 20 from the uppermost position of the auxiliary arm 20. Then, the arm 3 moves downward in a state in which it maintains the predetermined angle as shown in FIG. 6(e) and the lower end of the arm 3 reaches position E. Holding of the workpiece (not shown) is then released via the holding means 4.

(63) Conveyance of a workpiece is performed in this manner.

(64) In this respect, after conveying the workpiece, the guide portion 1a is moved to approximately center of the rail portion 1 and the slider portion 2a is moved to the lowermost side of the auxiliary arm 20. Then, the arm 3 and the auxiliary arm 20 rotate as shown in FIG. 6(f) and the lower end of the arm 3 moves leftward and reaches position F. At this time, the guide portion 1a, the rail portion 1, the slider portion 2a, the auxiliary arm 20 and the arm 3 will repeatedly be overlapped on the same line.

(65) Then, the guide portion 1a is moved to the lowermost side of the rail portion 1 and the slider portion 2a is moved from the lowermost position of the auxiliary arm 20 to a position closer to the upper side of the auxiliary arm 20. Then, the arm 3 and the auxiliary arm 20 rotate, the second shaft 3a moves leftward, and the lower end of the arm 3 reaches the position A as shown in FIG. 6(a).

(66) In the workpiece conveying method using the workpiece conveying device 100, it is possible to linearly convey a workpiece by sliding the guide portion 1a pivotally attached to the arm 3 along the rail portion 1 on one hand and by sliding the slider portion 2a pivotally attached to the arm 3 along the auxiliary arm 20 on the other hand.

(67) When a workpiece is sucked and held, the workpiece can be linearly conveyed in the lateral direction in a state in which it is lifted upward, and when no workpiece is sucked and held, the second shaft 3a at the lower end of the arm 3 can be moved linearly in the lateral direction without moving it upward. Namely, it is possible to move the second shaft 3a in the lateral direction via two types of paths.

(68) While a preferred embodiment of the present invention has been explained above, the present invention is not to be limited to the above embodiment.

(69) For instance, while the holding means 4 comprising the crossbar 4a connected to the second shaft 3a at the lower end of the arm 3 and suction portions 4b mounted to the crossbar 4a is used as a means which holds a workpiece W in the workpiece conveying device 100 according to the present embodiment, the present invention is not limited to this, and it is also possible to employ a gripper or the like.

(70) Further, while suction portions 4b comprised of a pair of right and left vacuum cups are mounted to the crossbar 4a at eight spots, spots and numbers of mounting the suction portions 4b are not limited to this.

(71) While one end of the crossbar 4a is coupled to the second shaft 3a at the lower end of the arm 3 in the workpiece conveying device 100 according to the present embodiment, it is also possible that a pair of workpiece conveying devices 100 is coupled to both ends of the crossbar. Namely, it is also possible that a pair of workpiece conveying devices 100 is coupled via the crossbar.

(72) While the slider portion 2a is mounted to the auxiliary arm 20 via the belt portion 2 in the workpiece conveying device 100 according to the present embodiment, the present invention is not limited to this configuration.

(73) For instance, it is also possible to provide a rail at the auxiliary arm 20 and to make the slider portion slide along this rail or to move the slider itself using wires or the like.

(74) While all of rotation of the holding means 4, rotation of the auxiliary arm 20 and the sliding of the slider portion 2a is performed through driving servomotors in the workpiece conveying device 100 according to the present embodiment, the present invention is not limited to this, and it might also be driving using invertor motors or the like.

(75) On the other hand, it is also possible to perform sliding of the guide portion 1a by driving a servomotor instead of rotation of the auxiliary arm 20.

(76) In the workpiece conveying device 100 according to the present embodiment, mounting of the reduction gears to the first servomotor, the second servomotor and the third servomotor is arbitrary.

INDUSTRIAL APPLICABILITY

(77) The workpiece conveying device according to the present invention is preferably used as a workpiece conveying device for conveying a workpiece used, for instance, for press working.

(78) According to the workpiece conveying device according to the present invention, a workpiece can be conveyed linearly with a light-weight and simple configuration.

REFERENCE SIGNS LIST

(79) 1 . . . rail portion,

(80) 1a . . . guide portion,

(81) 2 . . . belt portion,

(82) 2a . . . slider portion,

(83) 2b . . . first shaft,

(84) 3 . . . arm,

(85) 3a . . . second shaft,

(86) 3b . . . first pivotally attaching portion,

(87) 3c . . . second pivotally attaching portion,

(88) 4 . . . holding means,

(89) 4a . . . crossbar,

(90) 4b . . . suction portion,

(91) 7a . . . first servomotor (servomotor),

(92) 7b . . . third servomotor (servomotor),

(93) 7c . . . second servomotor (servomotor),

(94) 8a, 8b . . . reduction gear,

(95) 9a . . . follower pulley,

(96) 9b . . . drive

(97) 10 . . . main body portion,

(98) 20 . . . auxiliary arm,

(99) 100 . . . workpiece conveying device,

(100) P . . . press machine,

(101) P1 . . . post,

(102) W . . . workpiece,