Workpiece transfer apparatus with shifter and crossbar and workpiece transfer method using same

Abstract

A workpiece conveying apparatus capable of simultaneously conveying two workpieces includes a body section, a right arm and a left arm, the right arm and the left arm being attached to the body section, the right arm and the left arm being horizontally rotatable, a crossbar connected to the right arm, a first suction device attached to the crossbar, a shifter including an attaching section attached to the crossbar and a driving section configured to move with respect to the attaching section, and a second suction device attached to the driving section. The driving section is pivotally attached to a connector bar attached to the left arm, and the driving section is configured to move with respect to the crossbar on the basis of rotation of the right arm and the left arm.

Claims

1. A workpiece conveying apparatus capable of simultaneously conveying two workpieces, the workpiece conveying apparatus comprising: a body section; a right arm and a left arm being attached to the body section and being horizontally rotatable; a crossbar connected to the right arm; first suction means attached to the crossbar; a shifter attached to the crossbar; and second suction means attached to the shifter, wherein the shifter includes an attaching section and a driving section configured to move with respect to the attaching section, the attaching section includes a pair of front and rear guide rails, the driving section includes a base configured to move along the guide rails and auxiliary crossbars attached to the bases and extending in a length direction of the crossbars, the driving section is configured to move with respect to the crossbar on a basis of rotation of the right arm and the left arm, the crossbar has a plurality of holders on both sides thereof, the first suction means and the front and rear guide rails are attached to the holders, the second suction means are attached to the auxiliary crossbars, a connector bar attached to the left arm is pivotally attached to pins provided on the bases, the driving section is provided with a lock mechanism having claw portions that move as the pins move upward and downward, the claw portions protruding in a transverse direction from the pins, the guide rails are provided with downward grooves, in a case where the connector bar is detached from the pins, the claw portions move upward together with the pins and the claw portions are engaged in the grooves so that the bases do not move along the guide rails and are fixed, and in a case where the connector bar is fitted on the pins, the claw portions move downward together with the pins and the claw portions are detached from the grooves so that the bases are movable along the guide rails.

2. The workpiece conveying apparatus according to claim 1, wherein the shifter is attachable to and detachable from the crossbar.

3. The workpiece conveying apparatus according to claim 1, wherein the workpiece conveying apparatus is attached to a pressing machine for use.

4. A method for conveying workpieces by using a workpiece conveying apparatus according to claim 1, the method comprising: gripping one of the workpieces by the first suction means; gripping the other of the workpieces by the second suction means; and varying a distance between the workpieces by moving the driving section of the shifter while simultaneously conveying the workpieces.

Description

BRIEF DESCRIPTION OF DRAWINGS

(1) FIG. 1 is a perspective view showing a pressing machine to which a workpiece conveying apparatus according to the present embodiment is attached.

(2) FIG. 2 is a top view showing the workpiece conveying apparatus according to the present embodiment.

(3) FIG. 3 is a perspective view showing a part of the workpiece conveying apparatus according to the present embodiment.

(4) FIG. 4A is a perspective view of a connector bar of the workpiece conveying apparatus according to the present embodiment, with the connector bar cut perpendicularly to a longitudinal direction thereof. FIG. 4B(a) is a partially enlarged view of FIG. 4A, and FIG. 4B(b) is a reference view illustrating a groove shown in FIG. 4B(a).

(5) FIG. 5 is an explanatory diagram for explaining a method for conveying workpieces according to the present embodiment.

DESCRIPTION OF EMBODIMENTS

(6) A preferred embodiment of the present invention is described in detail below with reference to the drawings as needed. In the drawings, the same components are given the same reference signs, and repetition of the same descriptions is omitted. Further, unless otherwise noted, positional relationships such as top and bottom, left and right are based on those shown in the drawings. Furthermore, the dimensional ratios of the drawings are not limited to those shown in the drawings.

(7) A workpiece conveying apparatus of the present invention is used as an apparatus for simultaneously conveying two workpieces to a pressing machine. The press may be a tandem press line pressing machine or a transfer press line pressing machine.

(8) FIG. 1 is a perspective view showing a pressing machine to which a workpiece conveying apparatus according to the present embodiment is attached.

(9) As shown in FIG. 1, a pressing machine 1 is supported by four uprights 2, with a fixing bar 2a attached so as to bridge a pair of the uprights 2.

(10) Moreover, a workpiece conveying apparatus 100 has a body section 10 attached to substantially the center of the fixing bar 2a. That is, the workpiece conveying apparatus 100 is fixed to aside face of the pressing machine 1 via the fixing bar 2a.

(11) The body section 10 has ball screws 12a and motors 12b attached on both side thereof. The motors 12b are configured to drive the ball screws 12a.

(12) Further, the ball screws 12a and the motors 12b enable the workpiece conveying apparatus 100 to move upward and downward with respect to the fixing bar 2a via the body section 10. This allows the workpiece conveying apparatus to move up and down so as to be in an optimum position for the shape of a die, the shape of a workpiece, or the like.

(13) The workpiece conveying apparatus 100 is configured to simultaneously told two workpieces by suction and carry the workpieces into the pressing machine 1. In a case where another pressing machine is attached to an upstream side of the workpiece conveying apparatus 100, the workpiece conveying apparatus 100 is configured to hold by suction workpieces processed by the upstream pressing machine, carry the workpieces out of the upstream pressing machine, carry the workpieces into the pressing machine 1.

(14) In this way, the workpiece conveying apparatus 100 can be directly attached to the pressing machine 1. As such, the workpiece conveying apparatus 100 can compactly convey workpieces (carry workpieces out and carry workpieces in) without requiring a space.

(15) FIG. 2 is a top view showing the workpiece conveying apparatus according to the present embodiment.

(16) As shown in FIG. 2, the workpiece conveying apparatus 100 includes the body section 10, which is fixed to a pressing machine; a right arm 21 and a left arm 22 attached to the body section 10; a crossbar 3 connected to the right arm 21; first suction means 3a attached to the crossbar 3; a shifter 5 attached to the crossbar 3; and second suction means 7a attached to a driving section 16 of the shifter 5.

(17) Further, the shifter 5 includes an attaching section 15 and the driving section 16, which is configured to move with respect to the attaching section 15.

(18) The right arm 21 and the left arm 22 are rotatably attached to the body section 10, and the right arm 21 and the left arm 22 are symmetrically structured.

(19) The right arm 21 includes an upper right arm section 21a pivotally attached to the body section 10 and a lower right arm section 21b pivotally attached to the upper right arm section 21a. The right arm 21 is horizontally rotatable on a part of the body section 10 as an axis.

(20) Similarly, the left arm 22 includes an upper left arm section 22a pivotally attached to the body section 10 and a lower left arm section 22b pivotally attached to the upper left arm section 22a. The left arm 22 is horizontally rotatable on a part of the body section 10 as an axis.

(21) Moreover, the crossbar 3 is pivotally attached to a distal end of the lower right section 21b, and the driving section 16 of the shifter 5 is attached to a distal end of the lower left arm section 22b via a connector bar 8. It should be noted here that the attaching section 15 of the shifter 5 is attached to the crossbar 3 so that the driving section 16 of the shifter 5 can move along a length direction of the crossbar 3. The shifter 5 will be described in detail later.

(22) Therefore, the crossbar 3 is configured to be supported by the right arm 21 and also supported by the left arm 22 via the shifter 5. This makes it possible to dispersedly support the weights of even comparatively heavy workpieces W and carry the workpieces W in at a high speed.

(23) Further, horizontal rotation of the aforementioned right arm 21 and left arm 22 causes the crossbar 3 to move in the direction that the workpieces travel.

(24) The workpiece conveying apparatus 100 includes a plurality of holders 3b provided on both sides of the crossbar 3.

(25) Moreover, the first suction means 3a are attached to the holders 3b on the right arm 21 side of the crossbar 3, and the attaching section 15 of the shifter 5 is attached to the holders 3b on the left arm 22 side of the crossbar 3.

(26) It should be noted here that in the workpiece conveying apparatus 100, the shifter 5 is directly attached to the holders 3b of the crossbar 3. Specifically, the after-mentioned guide rails 6a of the attaching section 15 of the shifter 5 are detachably attached to the holders 3b of the crossbar 3. That is, the shifter 5 can be attached to the holders 3b of a crossbar to which suction means are attached, instead of the suction means. This allows a conventional crossbar to be used without any change.

(27) Therefore, for example, in a case where the shifter 5 is not used in conveying workpieces (i.e. in a case where there is no need to vary the distance between the workpieces), the shifter 5 may be detached and the first suction means 3a for gripping a workpiece may be attached to the holders 3b for use.

(28) Usable examples of the first suction means 3a are publicly known suction pads. In this case, a workpiece is gripped by suction with vacuum suction in the suction pads.

(29) FIG. 3 is a perspective view showing a part of the workpiece conveying apparatus according to the present embodiment.

(30) As shown in FIG. 3, in the workpiece conveying apparatus 100, the connector bar 8, which extends forward and backward, is fixed to the distal end of the lower left arm section 22b of the left arm 22.

(31) The shifter 5 includes the attaching section 15 and the driving section 16.

(32) The attaching section 15 includes a pair of front and rear guide rails 6a, and the driving section 16 includes bases 6b configured to move along the guide rails 6a, respectively, and auxiliary crossbars 7 attached to the bases 6b, respectively. It should be noted that each of the guide rails 6a is placed parallel to the crossbar 3.

(33) Attached to the bases 6b of the shifter 5 are pins 8a loosely fitted in holes provided in the connector bar 8, respectively.

(34) In the workpiece conveying apparatus 100, horizontal rotation of the left arm 22 causes the connector bar 8 to move in the length direction of the crossbar 3, and as the connector bar 8 moves, the bases 6b to which the auxiliary crossbars 7 are attached move along the guide rails 6a. That is, the driving section 16 of the shifter 5 moves in the length direction of the crossbar 3 with respect to the crossbar 3 on the basis of rotation of the right arm 21 and the left arm 22.

(35) In the shifter 5, each of the auxiliary crossbars 7 is provided with a plurality of auxiliary holders 7b.

(36) Moreover, the second suction means 7a are attached to the auxiliary holders 7b.

(37) It should be noted that as in the case of the first suction means 3a, publicly known suction pads can be used as the second suction means 7a.

(38) In the workpiece conveying apparatus 100 according to the present embodiment, the attaching section 15 of the shifter 5 is attached to the crossbar 3, the right arm 21 is connected to the crossbar 3, and the left arm 22 is attached to the bases 6b of the shifter 5 via the connector bar 8 and the pins 8a. This makes it possible to move the shifter 5 in the length direction of the crossbar 3 with respect to the crossbar 3 on the basis of rotation of the right arm 21 and the left arm 22 without providing a special device or a driving device.

(39) Further, since the first suction means 3a are attached to the crossbar 3, one of the workpieces can be sucked, and since the second suction means 7a are attached to the driving section 16 of the shifter 5, the other of the workpieces can be sucked at the same time.

(40) For these reasons, the workpiece conveying apparatus 100 is simple in structure and yet capable of simultaneously conveying two workpieces on the basis of rotation of the right arm 21 and the left arm 22 while varying the distance between the workpieces.

(41) FIG. 4A is a perspective view of the connector bar of the workpiece conveying apparatus according to the present embodiment, with the connector bar cut perpendicularly to a longitudinal direction thereof. FIG. 4B(a) is a partially enlarged view of FIG. 4A, and FIG. 4B(b) is a reference view illustrating a groove shown in FIG. 4B(a).

(42) As shown in FIG. 4A, the driving section 16 of the shifter 5 has a lock mechanism 11 provided in the bases 6b to fix the bases 6b to the guide rails 6a.

(43) Therefore, the lock mechanism 11 is configured to move along the guide rails 6a together with the driving section 16.

(44) Accommodated inside the lock mechanism 11 is the aforementioned pins 8a, on lower surfaces of which springs 13 are provided to bias the pins 8a upward. That is, the pins 8a are in a state of being pressed upward by the springs 13.

(45) Further, the pins 8a have claw portions 11a protruding in a transverse direction.

(46) In the workpiece conveying apparatus 100, the connector bar 8 at the distal end of the lower left arm section 22h is fitted on the pins 8a to press the pins 8a downward. Then, the pins 8a press the springs inside the lock mechanisms 11, and the claw portions move downward accordingly.

(47) Meanwhile, the guide rails 6a of the shifter 5 are provided with grooves 11b so that the claw portions 11a are inserted in the grooves 11b when moved upward. This causes the bases 6b to be fixed to the guide rails 6a to become unable to move along the guide rails 6a.

(48) Therefore in a case where the connector bar 8 of the left arm 22 is fitted on the pins 8a of the shifter 5, the claw portions 11a are detached from the grooves 11b and the bases 6b move along the guide rails 6a, and in a case where the connector bar 8 of the left arm 22 is detached from the pins 8a of the shifter 5, the claw portions 11a are inserted in the grooves 11b and the bases 6b do not move along the guide rails 6a and are fixed.

(49) Thus, in the workpiece conveying apparatus 100, the shifter 5 is provided with the lock mechanism 11 for fixing the bases 6b. Therefore, in a case where the shifter 5 is not used, unintended movement of the bases 6b can be prevented by fixing the bases 6b in the manner described above.

(50) The following describes a method for conveying workpieces by using a workpiece conveying apparatus.

(51) FIG. 5 is an explanatory diagram for explaining a method for conveying work workpieces according to the present embodiment.

(52) As shown in FIG. 5, the method for conveying workpieces includes first gripping a right side workpiece W1 by the first suction means 3a on the right arm 21 side and then gripping a left side workpiece W2 by the second suction means 7a of the left arm 22.

(53) Next, the workpieces W are horizontally conveyed by rotating the upper and lower right arm sections 21a and 21b of the right arm 21 and the upper and lower left arm sections 22a and 22b of the left arm 22.

(54) At this point in time, the driving section 16 of the shifter 5 moves along the length direction of the crossbar 3 extending in a direction perpendicular to the direction that the workpieces W1 and W2 travel. It should be noted that the moving distance that the driving section 16 of the shifter 5 moves is based on how the pair of right and left arms 21 and 22 rotate. The moving of the driving section 16 of the shifter 5 is performed by a set computer program.

(55) Then, the right arm 21 and the left arm 22 are moved to opposite sides, and in predetermined positions, the right side workpiece W1 is released bon/Um first suction means 3a of the right arm 21 and the workpiece W2 is released from the second suction means 7a of the left arm 22.

(56) After that, the right arm 21 and the left arm 22 are returned into their original positions by again rotating the upper and lower right arm sections 21a and 21b of the right arm 21 and the upper and lower left arm sections 22a and 22b of the left arm 22.

(57) In the method for conveying workpieces, the distance D2 between the workpieces W1 and W2 after conveyance is longer than the distance D1 between the workpieces W1 and W2 before conveyance. It should be noted that depending on the set computer program, the distance D2 between the workpieces W1 and W2 after conveyance can be made shorter than the distance D1 between the workpieces W1 and W2 before conveyance.

(58) Thus, the method for conveying workpieces makes it possible to vary the distance between the workpieces W1 and W2 by moving the driving section 16 of the shifter 5 during conveyance. That is, the method for conveying workpieces uses the aforementioned workpiece conveying apparatus to achieve a simple structure and yet make it possible to simultaneously convey two workpieces while varying the distance between the workpieces.

(59) The foregoing has described a preferred embodiment of the present invention. However, the present invention is not limited to the embodiment described above.

(60) For example, instead of a workpiece conveying apparatus 100 according to present embodiment being fixed to a side face of the pressing machine 1, workpiece conveying apparatuses 100 may be attached to both sides of the pressing machine 1, respectively.

(61) In the workpiece conveying apparatus 100 according to the present embodiment, the body section 10 is attached to substantially the center of the fixing bar 2a. Alternatively, the body section 10 may be attached to a position deflected to one side of the fixing bar 2a.

(62) In the workpiece conveying apparatus 100 according to the present embodiment, the crossbar 3 is pivotally attached to the distal end of the lower right arm section 21b, and the shifter 5 is attached to the distal end of the lower left arm section 22b via the connector bar 8. Alternatively, a left-right reversal may be made. That is, a crossbar may be pivotally attached to the distal end of a left arm section, and a shifter may be attached to the distal end of a lower right arm section via a connector bar.

(63) Further, the shifter 5 may be attached to the distal end of the lower left arm section 22b via a clamping device instead of the connector bar 8.

INDUSTRIAL APPLICABILITY

(64) A workpiece conveying apparatus of the present invention is used for example in press working as an apparatus for conveying workpieces to a pressing machine. The workpiece conveying apparatus of the present invention is simple in structure and yet capable of simultaneously conveying two workpieces while varying the distance between the workpieces.

REFERENCE SIGNS LIST

(65) 1 . . . pressing machine 2 . . . upright 2a . . . fixing bar 3 . . . crossbar 3a . . . first suction means 3b . . . holder 5 . . . shifter 6a . . . guide rail 6b . . . base 7 . . . auxiliary crossbar 7a . . . second suction means 7b . . . auxiliary holder 8 . . . connector bar 8a . . . pin 10 . . . body section 11 . . . lock mechanism 11a . . . claw portion 11b . . . groove 12a . . . ball screw 12b . . . motor 13 . . . spring 15 . . . attaching section 16 . . . driving section 21 . . . right arm 21a . . . upper right arm section 21b . . . lower right arm section 22 . . . left arm 22a . . . upper left arm section 22b . . . lower left arm section 100 . . . workpiece conveying apparatus W1, W2 . . . workpiece