GB2119761A

GB2119761A - Automatic work feeder

Info

Publication number: GB2119761A
Application number: GB08226672A
Authority: GB
Inventors: Masaru Orii
Original assignee: ORII JIDOKI SEISAKUSHO KABUSHI; ORII JIDOKI SEISAKUSHO KK
Current assignee: ORII JIDOKI SEISAKUSHO KABUSHI; ORII JIDOKI SEISAKUSHO KK
Priority date: 1982-04-24
Filing date: 1982-09-20
Publication date: 1983-11-23
Also published as: KR870000177B1; KR840001478A; JPS58187225A; JPS6361097B2

Abstract

An automatic work feeding apparatus 12 for use with a press 11 including a slide bar that has a work holding member 23 and which can be reciprocated between two points in the feed direction of the work, a vertically movable holder that holds the slide bar while allowing horizontal movement thereof, a power transmission mechanism 20, 28, 27 to be coupled to the slide 16 or the slide power transmission mechanism 18 of the press so as to be operated in use in synchronism with reciprocating motion of the slide 16, the power transmission mechanism being arranged to rotate a cam shaft 26 in opposite directions, a cam mounted on the cam shaft, two cam mechanisms, one to cause horizontal movement of the work holding member 23 and the other to cause vertical movement thereof, the cam mechanisms being movable in response to a change in the position of the cam face of the cam, and displacement transmission mechanisms arranged to transmit the motion of the cam mechanisms to the slide bar and to the holder 23. <IMAGE>

Description

SPECIFICATION Automatic work feeder The present invention relates to an automatic work feeder, and more particularly to an automatic apparatus for feeding workpieces with a slide drive using as a power source a press.

Conventional automatic feeders use a single motor as a power source to achieve a twodimensional operation of the wdrkpiece holder that consists of a reciprocal movement between two horizontal positions and a vertical movement at each position. But these feeders are unavoidably large since they contain either an electric motor or a pneumatic cylinder as a driving means. To convert the rotation of the motor shaft to the horizontal and vertical reciprocal movements of the work holder, the first type of feeder has two clutch mechanisms, one for horizontal movement and the other for vertical movement, in the path transmitting the power of the motor, and the respective clutches are let in or let out to control the horizontal and vertical movements.Therefore, the feeder of the first type is complex both in construction and timing control and is prone to trouble. The second type of feeder using a pneumatic cylinder involves difficulty in controlled switching from horizontal movement to vertical movement and vice versa, and many expensive control parts are necessary to accomplish a precise two-dimensional operation.

According to the present invention there is provided an automatic work feeding apparatus for use with a press including a slide bar that has the work holding member and which can be reciprocated between two points in the feed direction of the work, a vertically movable holder that holds said slide bar while allowing horizontal movement thereof, a power transmission mechanism to be coupled to the slide or the slide power transmission mechanism of the press so as to be operated in use in synchronism with reciprocating motion of said slide, the power transmission mechanism being arranged to rotate a a cam shaft in opposite directions, a cam mounted on said cam shaft, two cam mechanisms, one to cause horizontal movement of the work holding member and the other to cause vertical movement thereof, the cam mechanisms being movable in response to a change in the position of the cam face of the cam, and displacement transmission mechanism arranged to transmit the motion of the cam mechanism to said slide bar and to said holder.

The present invention thus provides an apparatus that feeds workpieces to a press in a predetermined sequence without a separate drive source but using the power output of the press.

In order that the invention may be more clearly understood, the following description is given by way of example only with reference to the accompanying drawings in which: Fig. 1 is a general front view of a preferred embodiment of automatic feeder according to the present invention; Fig. 2 is a simplified perspective view showing the internal mechanism of the feeder of Fig. 1; Fig. 3 is a front view, partially cut away, of the pusher mechanism of the feeder of Fig. 1; Fig. 4 is a front view, partially cut away, of the horizontal feed mechanism of the feeder of Fig. 1; and Fig. 5 is a side elevational view, partially cut away, of the feeder of Fig. 1.

Fig. 1 is a general front view of a press working apparatus that has incorporated therein an automatic feeder of the present invention. The press working apparatus generally indicated at 10 consists of a press 11 and an automatic feeder 12.

The press 11, which is a C type press, comprises a C type frame 13, a bolster 14, a lower mold 15, a slide 16, an upper mold 17, a motor (not shown) and a rotary shaft 1 8. When the press motor rotates the shaft 18, a cam mechanism (not shown) transmits power to the slide 1 6 which reciprocates in the direction indicated by the twoheaded arrow A and presses a workpiece 1 9 on the lower mold 1 5. Therefore, the rotary shaft 18 and cam mechanism make up a slide power transmission mechanism that transmits the motor power to slide 1 6.The rotary shaft 1 8 projects from the upper side wall of the frame 13 and its projecting end is provided with a rotary wheel 20 'that rotates together with the shaft 1 8. An eccentric pin 21 is provided at an eccentric point of the rotary wheel 20.

The automatic feeder 1 2 comprises a pusher mechanism 22 that pushes the lowest of a stack of sheet-like workpieces 1 9 in a magazine (not shown) from position a to b, and a horizontal feed mechanism 24 wherein a holding member 23 that engages the workpiece at position b by suction, carries it along the path indicated by the twoheaded arrow B (b-C-d) and positions it on the lower mold 1 5 (position e). The feeder 12 has a cam shaft 26 that is rotatably mounted on a frame 25 by ball bearings, and the cam shaft 26 is supported by the frame in a horizontal plane as shown in Fig. 2. The cam shaft 26 projects from the front side of the frame 25 and its projecting end is fixed to one end of a lever 27; the other end of the lever 27 being rotatably connected to one end of a long link member 28 by a pin 29.The other end of the link member 28 is pivotally connected to the eccentric pin 21 provided in the rotary wheel 20. Due to this arrangement, rotation of the shaft 1 8 on the press 11 causes vertical movement of the link member 28, which then causes the cam shaft 26 to swing through a predetermined angular range (not more than 18,00) in opposite directions as indicated by the two-headed arrow C. Therefore, the rotary wheel 20, link member 28, and lever 27 make up a power transmission mechanism that transmits part of the output power of the motor in the press 11 to the cam shaft 26.

Fig. 2 is a simplified perspective view of the mechanism incorporated within the frame of the automatic feeder 12. The cam shaft 26 has a single oscillating cam 30. Follower shafts 31 and 32 parallel to the cam shaft 26 are rotatably supported by the frame 25, and levers 33 and 34 are fixed to the respective follower shafts at one end. The levers have rollers 33a and 34a, respectively, which are urged against the cam face 30a and positioned to face each other via the oscillating cam 30. A spring (not shown) is loaded in selected positions to urge the rollers 33a and 34a against the cam 30.

A feed arm 36 for the pusher mechanism 22 that is rotatable via a ball bearing 35 is provided in the middle of the cam shaft 26. The periphery of the arm is provided with teeth 36a that engage a cogwheel 37 that rotates together with the follower shaft 32. As the cam shaft 26 rotates in two opposite directions as indicated by arrows C, and C2, roller 34a detects a change in the position of the cam face 30a, and as a result of this detection, the follower shaft 32 rotates in two opposite directions indicated by the arrows D1 and D2, whereupon like the cam shaft 26, the feed arm 36 rotates in two opposite directions as indicated by arrows E1 and E2.

As shown in Fig. 3, the forward end of the feed arm 36 is connected by a link 41 to one end of a pusher 40 having rollers 39 that travel on the base 38 of the pusher mechanism 22 in the feed direction, and as the arm 36 swings, the pusher 40 reciprocates on the horizontal plane. The upper surface of the pusher 40 has a recess 40a, and every time the pusher reciprocates, the side edge of the lowest sheet of the workpieces 1 9 stacked in a magazine (not shown) is pushed forward by the edge of the recess to point b in Fig. 1.

As shown in Fig. 4, a holder 42 6n the frame 25 is positioned between the pusher mechanism ?2 and the lower mold 1 5 on press 11; the holder contains two rows of vee-grooved rollers 42a that hold a rectangular slide bar 43 in the feed direction which is movable with respect to the holder 42 in the feed direction. The slide bar 43 has a holding member 23 at a point close to the forward end of an arm 44. The holding member 23 may be of magnetic suction type of chuck type, and in the illustrated embodiment, it comprises a pair of vacuum sucking pads. The underside of the holder 42 is rotatably connected by a pin to one end of each of two kinked flexible links 45, and the other end of each link is rotatably connected to one end of a straight link 46 by a pin, so that each kinked link 45 is rotatable around an axis 45a.The other end of the straight link 46 is rotatably connected by a pin to the forward end of a lever 47 fixed to the other end of the follower shaft 31.

Because of this arrangement, when the lever 47 is turned counterclockwise as seen in Fig. 4, the straight link 46 moved to the left and the pair of kinked links 45 are rotated clockwise around the axis-45a, whereupon the slide bar 43 as well as the holder 42 are pushed up, and if the lever 47 is subsequently rotated clockwise, the holder 42 is pushed down.

The follower shaft 31 having the lever 47 rotates according to the change in the position of the cam face 30a of the oscillating cam 30 on the cam shaft 26. The shape of the cam face against which the roller 33a is urged is so designed that the follower shaft 31 is rotated in directions F, and F2 according to the rotation of the cam shaft 26 in directions C, and C2, respectively (see Fig. 2).

The slide bar 43 has a horizontal feed arm 49 that is connected to the other end of the cam shaft 26 by a ball bearing 8, and the forward end of the arm 49 is rotatably connected to a slider 50 by a pin 49a, and the slider 50 is fitted in a vertically movable fashion in a groove 51 a defined by a guide frame 51 fixed to one lateral side of the holder 42. The base of the horizontal feed arm 49 is rotatably connected to one end of a link 52, and the other end of said link is rotatably connected to one end of an arm 53 fixed to the other end of the follower shaft 32.Because of this arrangement, when the cam shaft 26 is rotated in a direction indicated by arrow Ct and C2 as shown in Fig. 2, the horizontal feed arm 49 is rotated around the cam shaft 26 in a direction indicated by arrow G or G2 (Fig. 4) and the slide bar 43 as guided by rollers 42a is moved horizontaliy in a direction indicated by, arrow H1 or H2 (Fig. 4). The horizontal feed arm 49 is connected to the slide bar 43 by the guide frame 51 and slider 50 to absorb any undesired vertical movement of the arm 49, and the work can be fed smoothly on the horizontal plane without vertical fluctuation of the slide bar 43.As shown in Fig. 4, the components of Fig. 2 are contained in a cam box 54.

As described in the foregoing, the automatic feed of the present invention has a power transmission mechanism that is coupled to the slide power transmission mechanism of the press and whidh is operated in synchronism with the reciprocating motion of the slide 1 6 to rotate the cam shaft 26 in two opposite directions. Because of this mechanism, the feeder is capable of reliable feeding the work by effecting the two-dimensional operation of the holding member 23 without using a separate drive source such as a motor. Another advantage of this mechanism is that it offers a compact and simple feed system. In the illustrated embodiment, the power transmission mechanism comprises rotary wheel 20 and elongated link 28.

The mechanism can be further simplified by a pinion mounted on the cam shaft 26 that engages a rack fixed to the slide 1 6. As a further merit, the cam shaft 26 is so designed that it is rotated in two opposite directions over a range of almost 1800, and this enables the two rollers 33a and 34a to be positioned in a face-to-face relation for detecting a change in position of the cam face 30a on a single oscillating cam 30, and as a result, the overall construction ofthe power transmission mechanism is further simplified.

This simplicity in construction coupled with the use of power from the slide power transmission mechanism of the press, enabies timed two dimensional operation of the holding member 23 in conjunction with the reciprocal motion of the slide, hence high-speed feed of the work. In addition, the feeder has a pusher mechanism that temporarily brings the work close to bolster 14 in synchronism with the rotation of the cam shaft 26 in two opposite directions, and because of this arrangement, the feeder has a simple construction in spite of the use of the pusher mechanism, and effects timed horizontal feed of the work. It is to be understood that the work can be brought close to the bolster temporarily be another mechanism such as a belt conveyor driven by the rotation of the. cam shaft.

Claims

1. An automatic work feeding apparatus for use with a press including a slide bar that has a work holding member and which can be reciprocated between two points in the feed direction of the work, a vertically movable holder that holds said slide bar while allowing horizontal movement thereof, a power transmission mechanism to be coupled to the slide or the slide power transmission mechanism of the press so as to be operated in use in synchronism with reciprocating motion of said slide, the power transmission mechanism being arranged to rotate a cam shaft in opposite directions, a cam mounted on said cam shaft, two cam mechanism, one to cause horizontal movement of the work holding member and the other to cause vertical movement thereof, the cam mechanisms being movable in response to a change in the position of the cam face of the cam, and displacement transmission mechanisms arranged to transmit the motion of the cam mechanisms to said slide bar and to said holder.

2. An automatic work feeding apparatus according to claim 1, wherein each of said cam mechanisms has a roller urged against the cam face to detect a change in its position, the two rollers being positioned in a face-to-face relation with respect to a single cam.

3. An automatic work feeding apparatus according to claim 1 or 2 including a horizontal feed mechanism to carry the work to the first of said points, and a displacement transmission mechanism that operates said horizontal feed mechanism upon rotation of said cam shaft.

4. An automatic work feeding apparatus constructed and arranged substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

5. The combination of a press and an automatic work feeding apparatus according to any preceding claim, with the slide or slide power transmission mechanism of the press being coupled to the power transmission mechanism of the work feeding apparatus.

6. The combination of a press and an automatic work feeding apparatus substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.