US3017040A - Stacking apparatus for sheet material - Google Patents

Description

Jan. 16, 1962 H. BOBST STACKING APPARATUS FOR SHEET MATERIAL Filed July 9, 1957 3 Sheets-Sheet 1 Jan. 16, 1962 H. BOBST STACKING APPARATUS FOR SHEET MATERIAL 3 Sheets-Sheet 2 Filed July 9, 1957 Jan. 16, 1962 o s 3,017,040

STACKING APPARATUS FOR SHEET MATERIAL Filed July 9, 1957 3 Sheets-Sheet 3 United States Patent ()fifice BJHZM-d Patented Jan. 18, 1962 3 $17,040 STACKKNG APPARAT US FQR SHEET MATERIAL Henri Bohst, Lausanne, Switzerland, assignor to J. Bobst and Son A., a corporation of witzerland Filed duty 9, 1957, Ser. No. 676,776 1 Claim. (Ci. 214-6) The present invention relates to a punching press for sheet material such as paper or cardboard.

In presses of this type, after the punching operation the resulting blanks are generally freed from the waste before being ejected. In this case, the press includes, besides the actual operation station, a reception station and other stations where part or all of the waste is ejected.

The press according to the present invention, whether of one or the other of the types under consideration, is fitted with a mobile device consisting of a retractable support intended to receive a pile of worked pieces and with a conveying device receiving and evacuating the pile each time the support retracts and the pile falls upon the conveyor which, owing to its mobility and dimensions, is convenient for mounting the retractable support in any position chosen under the receiving station of the worked pieces. Further, a counter of the worked pieces is provided, for causing the temporary retraction of the support whenever the pile heaped upon it reaches a pre-determined number of pieces.

The main advantage of the above arrangement consists in the fact that the reception of the worked pieces can be efiected as required, not only in counted bundles, but also continuously, that is to say, without it being necessary to interrupt the working of the press, as is the case when removing single piles of pieces received on a tray which drops down gradually as the pile is formed. Furthermore, the mobility of the device permits, on the one hand, the complete elimination of this device when a conventional method of reception is used, and, on the other hand, according to the type of press, the setting of the device at will under any one of the stations which functions at the time as a receiving post with, in addition, the possibility of placing the device in such a way that the retractable support is always in a suitable position with respect to the size of the worked pieces to be received.

The annexed drawing represents an embodiment of the invention given by way of example in the case of a press in which the location of the receiving station can vary according to the method of work adopted. A press of this type is described more fully in co-pending application Serial Number 586,018.

FIG. 1 is a schematic side elevation view of the press mentioned above and shows how a device embodying the present invention may be associated therewith; FIG. 2 is a diagrammatic side elevational view of the device of FIG. 1, but on a larger scale; FIG. 3 is a half side elevation of an accessory which is useful in connection with the device of FIG. 2; and FIG. 4 is a half elevation of the accessory of FIG. 3.

The press shown by way of example in FIG. 1 consists of the base 1, containing mechanism which is not shown here and not part of the invention, but which operates as follows:

At station A, punching the sheets between platens;

At station E, ejecting all waste with the exception of part of the sheet by means of which the punched piece is held for feeding into the machine, the ejected waste falling in the direction of arrow 2 on to a moving inclined plane 3;

At station C, called the reception station, ejecting the pieces themselves, which are freed from their waste and fall in the direction of arrow 4 and form a pile 5;

At station .1), finally, ejecting in the direction of arrow 6, that waste part of the sheet by which the piece ejected at station C was conveyed, this waste part falling on to a transverse conveyor belt 7.

Generally speaking, the sheets are registered before arriving at point A, and are conveyed from one position to the other by means of gripper bars driven by endless chains 8 which are periodically advanced.

It is obvious that any other continuous or intermittent method of conveyance can be employed.

It should be noted that although in the above described operation of the press, the finished pieces are ejected at station C, that is, the next to the last station, whereas a certain amount of waste remains attached to the gripper bars and such waste is ejected at the last station D, it would also be possible to operate the press so that the sheets bearing the finished pieces would be ejected at station D.

Pile 5 formed by the pieces falling in the direction of arrow 4 rests on a moving device consisting of a frame 9 mounted on wheels 10, thus enabling it to be displaced at will with respect to the press or even to be removed altogether.

The pile 5 is supported on this device by means of two flaps 19 and 20 placed transversely to the direction of displacement of the sheets in the press and to the direction in which frame 9 may be moved under the latter. These flaps are connected to rods 11 and 12 pivoted on the upper ends of levers 13 and 14 which pivot around their lower ends.

The reference numeral 15 indicates a mechanism of any appropriate type which, by means of two rods 16 and 17, can cause levers 13 and 14 to oscillate temporarily by pushing them apart, that is to say by pushing lever 13 to the left and lever 14 to the right from the positions thereof shown in FIG. 1 of the drawing.

This results in retraction of the two flaps holding pile 5 so that the latter drops to the position indicated at 5 on a conveyor belt 23 which extends along the whole length of the upper part of frame 9 and moves in the direction of arrow 18 to convey the pile to the position indicated at 5".

As shown in greater detail in FIG. 2, the flaps 19 and 20 extending transversally to the longitudinal and displacement axis of frame 9, slide horizontally in U-shaped channel members of the frame, as indicated at 21, and in which they are guided by rollers 22. The broken section appearing on the right hand side of FIG. 2 shows this arrangement in greater detail and at the same time the flap 2B is shown in a retracted position whereas flip 19 is in its normal position, in which .it supports the worked pieces forming pile Sin FIG. 1.

As already mentioned. the mechanism 15 serves to effect the temporary retraction, i.e. the wi.hdrawal to th left and to the right, with reference to the positions in FIG. 1 of the drawing, of the flaps 19 and 213. This mechanism can, for example, be an electro-motor coupled by a single revolution clutch with two cranks connected with rods 16 and 17, and which is controlled by any suitable system to make the cranks eifect a complete revolution, that is to say a to-and-fro oscillation of the two levers 13 and 14.

The longitudinal conveyor belt 23 serving to convey the piles of pieces in the direction of arrow 18 can be continuously driven for instance by an electro-motor located at 24.

The finished pieces, once rid of their waste, fall in the direction of arrow 4 fall upon the flaps 19 and 20, then on to the conveyor belt 23 when the flaps retract.

Since the size of the sheets to be processed may vary, the pieces arranged in piles may be of various dimensions, according to the work performed. Further, it is necessary that the median passing between the two adjacent edges of the flaps 19 and 20, when they are together, should pass practically beneath the center of the piled up pieces, so that, at the moment of retraction, the pile is left unsupported by the two opposed edges simultaneously, otherwise the pile would be upset or tilted instead of falling fiat on to the conveyor belt. This is precisely one of the advantages of the device being movable on wheels 10 as has been described, since it enables the flaps 19 and 20 to be placed in proper position below the reception station. Once this position is attained it is retained during any given job, by a suitable locking means for example, a pin 25 which is to be inserted into one of a series of holes which can be provided in the receiving plate of the press. This receiving plate of the press may also carry rails to guide the wheels 10.

Referring again to FIG. 1, it should be mentioned that somewhere on the machine there is to be provided a counter serving to record the number of finished pieces falling upon the pile 5, the purpose of this counter being to actuate a part of the mechanism 15, which, for instance, can be the single revolution clutch already mentioned. The counter actuates such clutch each time a pre-determined number of pieces falls upon the pile 5, that is to say whenever the flaps are to be retracted to drop the pile at on to the conveyor belt 23, for instance for each lot of ten, fifteen or twenty pieces delivered and piled.

The counter can be either mechanical, electrical or photo-electrical and should preferably be placed on the press and be able to act upon the mechanism both mechanically and electrically.

At high speeds, however, an absolute synchronization must exist between the rhythm at which the pieces fall in the direction of arrow 4 on to the pile 5 and the instant when the flaps 19 and 20 are retracted so as to ensure that once the pile has dropped, the flaps are returned to their normal position and are ready to receive the first sheet of the following pile.

To ensure this synchronization, the counter can be made to close an electrical circuit controlling mechanism 15 upon the deposit of a predetermined number of pieces in pile 5, but this circuit must then be closed by an additional switch controlled by an element of the mechanism of the press.

All the operations just described can naturally take place not only below station C, but below stations B or D as well, in case one of the latter i the receiving station, simply by shifting the device described above and positioning it where it is required for the reception of the sheets falling in piles in the direction of arrow 2 or arrow 6. The associated press may also have only two stations, namely stations A and B.

Since in the example described here the pieces are ejected at station C while, at station D, the grippers of the bars conveying the sheets through the press discard waste, it is apparent that such waste would drop either onto the conveyor belt 23 or onto a moving pile of pieces.

In order to avoid this, an accessory is provided formed by the frame 26 mounted on wheels 27 and able to straddle the device previously described. The frame 26 has a transverse conveyor belt 7 intended for the lateral evacuation of the waste ejected at station D.

FIGS. 3 and 4 show this straddle frame 26 on a larger scale and in the half views from the side and the front respectively. The frame 26 i provided with its own motor, not shown in the drawing. Transport of the waste can, for instance, be effected in the direction of arrow 28, with the waste falling in the direction of 4 arrow 29 (FIG. 4), outside the profile of the pilereceiving device, which is indicated X.

The foregoing description naturally applies to presses other than the type specifically mentioned herein by way of example, and the device can be used for the reception of pieces of paper or of cardboard, but it is particularly suitable when the material is either a thick cardboard or pieces of corrugated cardboard.

Although it has been stated that the device fitted with retracting flaps 19 and 20 and conveyor belt 23 extends in the direction of conveyance of the sheets across the press, obviously, the device might as well be designed for positioning at right angles to this direction. In the latter case, the additional conveyor belt 7 of the frame 26 would no longer be necessary.

What I claim is:

Apparatus for stacking and transporting flexible cut sheets received from the reception station of a punch press thereabove, comprising a frame movable to a position below the reception station of the punch press, a continuously operable conveyor carried by said frame for transporting stacks of the cut sheets fromunder the reception station, a pair of horizontal flaps, means supporting said flaps on said frame in a horizontal plane above said conveyor and guiding said flaps for simultaneous movements toward and away from each other in said horizontal plane between closed positions, wherein said flaps are juxtaposed to intercept and support the successive cut sheets falling from the reception station and, thus, forming a stack of sheets on said flaps, said flaps cooperatively supporting said flexible sheets in a stack of juxtaposed horizontal planes and retracted positions, wherein said flaps are relatively widely spaced apart simultaneously and instantaneously to permit the stack of cut sheets previously formed on the flaps to fall evenly and undeformed between the latter onto the underlying conveyor, and means for intermittently efiecting the movement of said flaps from said closed positions to said retracted positions and then back to said closed positions for again intercepting and supporting the cut sheets falling from said reception station, said means for intermittently effecting the movement of the flaps including levers pivotally supported at their lower ends for swinging movements in vertical planes parallel to the directions of movement of the flaps between said closed and retracted positions, links pivotally connected at their opposite ends to the upper ends of said levers and to said flaps, respectively, so that said flaps move between said closed and retracted positions in response to rocking of said levers toward and away from each other, and means for simultaneously rocking said levers.

References Cited in the file of this patent UNITED STATES PATENTS 1,466,177 Lacke Aug. 28, 1923 1,600,958 Hart et al. Sept. 21, 1926 2,000,273 Conklin et al. May 7, 1935 2,424,093 Harred July 15, 1947 2,488,675 Mallot Nov. 22, 1949 2,615,376 Pelikan Oct. 28, 1952 2,627,354 Isella et al. Feb. 3, 1953 2,701,650 Stevenson Feb. 8, 1955 2,710,696 Fontaine et al. June 14, 1955 2,793,693 Menk May 28, 1957 2,947,428 Curtenius Aug. 2, 1960 FOREIGN PATENTS 905,356 Germany Mar. 1, 1954

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