GB2048221A

GB2048221A - Box-blank Forming Machine

Info

Publication number: GB2048221A
Application number: GB7914981A
Authority: GB
Original assignee: SHII LIE LAIW; WUU SHYONG JOU
Current assignee: SHII LIE LAIW; WUU SHYONG JOU
Priority date: 1979-04-30
Filing date: 1979-04-30
Publication date: 1980-12-10

Abstract

An improved feed arrangement for a box-blank forming machine brings a paper board blank for forming to the press (3) at the same time as it removes the previously-formed blank. The conveyor for doing this is in the form of spaced-apart bands (5) driven stepwise from the main drive of the machine by an intermittent drive formed by a control wheel (1) with eccentric arm (13) and drive stud (14) registering with a cross-wheel (2). Each part-rotation of the cross-wheel (2) by the stud (14) causes one-fourth travel of the conveyor bands (5), because four is the number of pairs of clips (4) which are provided on the bands for holding the board. These are automatically opened at a loading position and a release position by ramps (51 and 51' respectively). <IMAGE>

Description

SPECIFICATION Box-blank Forming Machine This invention relates to box blank forming machines namely those machines which cut out (partially or completely) a shape and form fold lines in a web or sheet of paperboard to define a blank which can then be erected into a box.

Conventionally there are two general types of this machine one in which the paperboard is manually placed in the press area of the machine where the board is to be operated on and then manually removed from it; and the other where there is automatic delivery of the board to that area and then automatic return. The first type has its dangers and is labour-intensive; the second is time-consuming in that there is a long feed time for each forming operation.

The present invention is concerned to improve the feed arrangements in such a machine and in particular arrangements which feed material for forming the blank towards the press area while at the same time removing a previously-formed blank from that area.

To achieve this a conveyor system is provided which brings paperboard step-wise to the press area, the stepwise movement of the conveyor being synchronised with movements of the press from the driving gear of the press itself. It is provided with means for attaching the paperboard to the conveyor and the stepwise movement of the conveyor is 1/nth of its pitch, where n is the number of attachment means provided around the conveyor. The attachment means are preferably clips arranged on respective spacedapart parallel bands which make up the conveyor means, the clips being automatically operated, being automatically placed in an open or closed position according to the position they have reached on the conveyor in the respective runs.

Thus the board may be automatically held to or released from these attachment means.

A particular embodiment of the invention will now be described with reference to the accompanying drawings, wherein: Fig. 1 is a side view of the blank forming machine; Fig. 2 is a front view; Fig. 3A is a detail seen in side view; Fig. 3B is a section on the line B-B of Fig. 3A; Fig. 4A is a detailed side view of another detail; Fig. 4B is a section on the line B-B of Fig. 4A; Figs. 5A and 5B show side views of clips on the conveyor means respectively in a closed and open condition and Fig. 5C is a top view of such a clip.

The blank forming machine has a base 72 a main frame 71 and an auxiliary frame 6 which act to support and bear the various mechanical parts to be described.

A continuously operating motor 9 drives through a pulley and belt drive a fly wheel 10 which is keyed to a main drive shaft 81. Pinions 11, 11' at respective ends of the shaft mesh respectively with pinions 12, 12' on a second drive shaft 8. Link arms 31 (Fig. 1) are pivoted eccentrically on pinions 12, 12' and extend to a draw shaft 32 on a press unit 3 which is pivotally mounted at 33 on the frame of the machine so as to be able to rock between the full line and dotted line positions shown in Fig. 1. In the full line position a press tool borne on one face of the press unit 3 is brought into contact with paperboard against an anvil block 34.

Also keyed to the shaft 8 is a control wheel 1 which has arcuate concave bits out of its external periphery and to which is secured an eccentric arm 13 having at its end a projecting drive stud 14. The drive stud 14 projects back over the plane of the control wheel 1.

In register with the control wheel 1 is pivotally borne on the shaft 81 a cross wheel 2 which is secured for rotation to a pulley wheel A. These two wheels are borne on the shaft 81 through a bearing 22 so that they are rotatable relative to the shaft 81.

As best seen in Fig. 3A the cross wheel has a fourfold symmetry with slots 21 at each quadrant and arcuately indented concave periphery between the slots. The concavity of these indents has the same radius of curvature as the convex part of the periphery of the control wheel 1 so that engagement between those peripheries locks the cross wheel 2 rotationally, the control wheel remaining free to rotate. This locking also ensures registration of the entry to a slot 21 with the drive stud 14 as the control wheel 1 rotates with the eccentric arm 13. As the stud 14 engages in a slot 21 the concave portion of the periphery of the wheel 1 is registering with the cross wheel 2, the cross wheel is unlocked and rotation of the latter is thereby permitted under the influence of the drive stud 14.

This rotation, which is through 900 before the stud passes outwardly from the slot is communicated to the pulley A and thence through pulley B to a conveyor drive shaft 82 which are mounted at each end conveyor drive pulleys C, C'.

Parallel conveyor bands 5 (Fig. 2) are stretched around these pulleys C, C' and idler pulleys D,D', E, E' and F, F' to form an endless path which is quadrangular in side view (Fig. 1). The throw of the drive stud 14 and the diameters of the cross wheel and the various pulleys A, B, C is arranged such that each 900 rotation of the cross wheel causes travel of the conveyor bands for onefourth of the pitch of their endless path.

On the conveyor means formed by two spacedapart conveyor bands 5 there are in this embodiment four pairs of board-transporting clips 4 which are arranged equidistantly around each band and laterally opposed, as between the bands, across the machine. The positioning of the pulleys C, D, E and F which define the ends of the respective planar runs of these bands is such that when a clip 4 has just passed the convexity in which it rounds the pulleys D, D' the next three clips along the band in its direction of travel are resepctively about to round the pulleys E, F and C respectively.

As best seen in Fig. 5 provision is made for automatically opening the clips of the pair of clips which arrive at certain positions around that path.

We shall describe the position adjacent the pulley D seen in Fig. 1.

Each clip consists of a triangular side plate 44 of which the top portion is bent over so as to secure by means of a screw 46a a fixed upper jaw 41 of the clip. A lower jaw 42 is pivotable about the axle 43 which projects from the side plate 44 and is urged by U-spring 47', towards its closed position seen in Fig. 5A. Lower jaw 42 continues as a lever arm portion from which projects an axle on which there is a roller 47 which is in register, as the conveyor band progresses, with a stationary ramp 51. When the travel of the conveyor brings the roller 57 onto the ramp 51 the jaws 41 and 42 will be opened and paperboard can be inserted between or removed from their gripping plates 48 which overlap each other laterally so as to overlie one another.

Similarly a ramp 51' is provided before the turn around the pulleys C to open clips also arriving at that position.

In operation the motor 9 is run continuously so that a pivotal reciprocation is imparted continuously to the forming press unit 3 by rotation of the second drive shaft 8 and the throw imparted to the link arms 31. This same rotation causes continuous rotation of control wheel 1 and arm 1 3 and as a result intermittent rotation of cross wheel 2 and intermittent travel of conveyor bands 5. The position at which the conveyor bands pause and in which the cross wheel 2 is located stationary by the control wheel 1 are those in which the clips adjacent pulleys D are held open by ramps 51 and the clips adjacent pulleys C are held open by ramps 51'. Paperboard may be therefore manually inserted between the holding plates 58 of these clips while they are open at the position adjacent the pulley D and then when the conveyor moves the clips will close and hold the board through the two steps it takes to reach the position where it is acted on by press unit 3. The blank duly cut and with crease lines imposed on it by press unit 3 (which is brought up against anvil 34 by rotation of the shaft 8 while the conveyor as a whole is stationary) is then brought in the next step to a position where the clips 4 are opened by ramps 51' and the formed board is free to escape down a delivery chute 52.

In subsequent stages the blank if not completely severed from the board will be knocked out of the skeleton of the board and will be erected or sent away for erection.

Claims

1. Box-blank forming machine having a common drive for the box-blank forming press and for feed means for bringing paperboard to and from the press, the feed means including endless conveyor means having a path passing through the area where the press acts on paperboard to form the blank and means for holding the board whereby to bring simultaneously board to the area and a formed blank from the area, the drive for the conveyor means imposing stepwise movement on the conveyor means with a stationary period synchronised with the operation of the press on the board.

2. Box-blank forming machine according to claim 1 wherein the stepwise movements of the conveyor means is imposed by continuous rotation of a control wheel with eccentric drive stud, registering with a cross-wheel intermittently driven by engagement with the drive stud, and a drive from the cross wheel is the conveyor means.

3. Box-blank forming machine according to claim 2, wherein the control wheel has a major portion of its periphery convex to be engageable with concavities in the periphery of the cross wheel to lock the latter against rotation and a minor portion of its periphery related to the position of the drive stud to unlock the crosswheel and allow its rotation under the influence. of the drive stud.

4. Box-blank forming machine according to claim 2 or claim 3 wherein an eccentric drive for reciprocating the press and the control wheel are mounted on a common, continuously rotatable, shaft.

5. Box-blank forming machine according to any one of the preceding claims wherein there are an an attachment means equally spaced around the endless conveyor means for holding board to the conveyor means, each stepwise movement of the conveyor means being 1/nth of its pitch.

6. Box-blank forming machine according to claim 5 wherein n is 4.

7. Box-blank forming machine according to any one of the preceding claims wherein the conveyor means includes a spaced-apart pair of endless bands each passing round a plurality of spaced apart pulleys to define a polygonal path, a loading station being one run of the path, the press area being on another run and the unloading station on a third.

8. Box-blank forming machine according to claim 7 wherein the holding means are clips operated automatically in relation to their position in the path of the conveyor means, to be opened to release or accept board and to be closed to retain it.

9. Box-blank forming machine according to claim 8, wherein the clips include a fixed jaw and a movable jaw, the movable jaw being resiliently urged towards a closed, board-holding, position but having a cam-follower on a lever arm, the cam-follower being engageable with cam-means adjacent the conveyor means to control opening and closing of the clip.

10. Box-blank forming machine according to claim 9, wherein there are two such cam means engageable during one circuit of the clips, one being at a loading station and one at a release station.

11. Box-blank forming machine substantially as herein described with reference to and as illustrated in the accompanying drawings.