US2033320A - Sheet feeder - Google Patents

Description

March 10, 1936. F. R. BELLUCHE SHEET FEEDER Filed Oct. 17, 1934 Patented Mar. 10, 1936 UNITED STATES PATENT orrica SHEET FEEDER Application October 17, 1934, Serial No. 748,632

2 Claims.

This invention relates to improvements in sheet feeding devices for printing machines and the like and refers more particularly to a sheet feeder of the type forming the subject matter of the copending application of Frank R. Belluche, Se-

rial No. 723,092, filed April 30th, 1934.

In the said copending application, individual sheets are carried from a pile by means of a fast moving endless chain conveyer to be disposed on slow moving tapes which advance the sheets to the guides of the printing press or other machine being fed. During the time the sheets are conveyed from the pile to aposition over the slow moving tapes, they are positively held by the grippers of the endless chain conveyer, but while they are advanced to the press by the slow moving tapes, the only control over the sheets is that obtained by friction between the sheets and the tapes resulting from the weight 29 of the sheets. Hence, during this interval the sheet is not positively controlled and as a result, the timing of its presentment to the press is often inaccurate.

It is therefore an object of the present inven- 25 tion to provide means for holding the sheet down onto the slow moving tapes during its advance thereby to the press.

More specifically it is an object of this invention to provide pneumatic means for holding an the sheet down onto the slow moving tapes,

which is so coordinated with the drive of the tapes as to become effective the instant the sheet is deposited thereon, and to become ineffective the instant the sheet reaches the front guides 35 of the press.

With the above and other objects in view which will appear as the description proceeds, this invention resides in the novel construction, combination and arrangement of parts substantial- 40 ly as hereinafter described and more particularly defined by the appended claims, it being understood that such changes in the precise embodiment of the herein disclosed invention may be made as come within the scope of the claims.

The accompanying drawing illustrates one complete example of the physical embodiment of the invention constructed according to the best mode so far devised for the practical ap 5o plication of the principles thereof, and in which: Figure 1 is a view diagrammatically illustrat ing one embodiment of this invention;

Figure 2 is an enlarged section view through line 2 2 of Figure 1; and

Figure 3 is a detail section view through Figure'2 on the plane of the line 3-3.

Referring now more particularly to the accompanying drawing in which like numerals indicate like parts throughout the several views, 5 the numeral 5 represents the receiving cylinder of a printing press or other machine to be fed, and the numeral 6 indicates the front guide of the press with which the leading edges of the sheets engage as they are presented to the ma- 10 chine.

In the embodiment illustrated, the sheets are brought to the feeder in a pile or stack 1 which is automatically elevated by suitable means (not shown) to position the topmost sheet for re- 5 moval therefrom and disposition between initial feed rollers 8 in the conventional manner. The rollers 8 present the sheets individually to grippers 9 carried by an endless chain conveyer ill.

The specific construction of the grippers 9 and the conveyer 10 forms no part of this invention and is therefore illustrated only diagrammatically. Any suitable drive may be provided for the conveyer, and as will be readily apparent, the drive for the conveyer is so timed that the grippers 9 are successively positioned to receive the sheets as they are picked off the pile and advanced by the rollers 8.

The grippers 9 of the conveyer l0 convey the sheet forwardly over a slow moving endless tape conveyer ll trained about rollers l2 and I3 so located as to position the upper stretches of the endless "tapes II in a common plane slightly beneath and preferably parallel to the lower run of the conveyer i0.

As has been indicated, the endless tape conveyer ll travels slowly, that is, with respect to the speed of the conveyer Ill. Theconveyer l0 quickly carries the sheets forwardly over the tape conveyer and drops the sheets thereon as the 4 grippers reach the front end of the conveyer.

During the remaining distance the sheets travel before reaching the press, they are advanced solely by the slow moving endless tape conveyer II. If the sheets were merely allowed to rest on the tapes by their own weight and no other means were provided for holding the sheets during their advancement to the press by the tapes, it is apparent that little if any control over the sheets would be had during this intervaL. and the timmg of their presentment to the press would often be inaccurate. This was a disadvantage of all past tape conveyers. part of the mechanism taken on the plane of the To overcome this disadvantage, means are provided to substantially positively hold the sheets 5 down onto the tapes during their conveyance by the tapes. For thispurpose suction cups M are placed underneath each tape with ports 15 closed only by the tapes. Consequently, the effect of suction within the cups I4 is transmitted through the ports l5 and the pores of the tapes to a sheet resting on the tapes to substantially positively hold the sheet down onto the tapes. This action is somewhat similar to that occurring in the air wheel used in some feeding devices for advancing the sheets.

Any desired manner of mounting the suction cups may be employed, but as it is desirable to have them adjustable with respect to the longitudinal stretch of the tape conveyer so as to accommodate sheets of different lengths, they are preferably mounted on a transverse supporting bar I6 whose ends H are slidably received in convey er.

guideways l8 of fixed longitudinal rails l9. Clamping screws 20 are provided to secure the transverse bar Hi to the supporting rails I 9 in adjusted position.

All of the suction cups l4 arecommunicated through hose connections 2|, and a flexible hose 22 connects one of the outermost suction cups with a valve housing 23 having a valve 24 and a connection 25 leading to a source of vacuum.;

When the valve 24 is open, the suction cups H are operative and vice versa.

Inasmuch as the time when the suction holding the sheet down onto the tape conveyer is to become effective and rendered ineffective must be coordinated with the advance of the sheets by the tape conveyer, the opening and closing of the valve 24 is coupled with the drive for the tape This may be accomplished by providing a cam 26 mounted on a drive shaft 21 and arranged to actuate a rocker arm 28 to intermittently push the valve open, the drive shaft also providing a drive for the tape conveyer.

To drive the tape conveyer, the drive shaft 21 has a gear 29 fixed thereto to drive a pinion 30 fixed to the shaft of the rollers l2 through an idler gear and pinion 3| and 32, respectively. The ratio of the gear connection between the drive shaft 21 and the shaft of the rollers I 2 is such that proper coordination between the functioning of the cam 26 and the drive of the tape conveyer is obtained, the cam being set so that the suction becomes effective the moment the sheet is released from the grippers Sand is shut off the instant the leading edge of the sheet reaches the front guide 6 of the press.

From the foregoing description taken .in connection with the accompanying drawing, it will be readily apparent to those .skilled in the art, that this invention affords novel and efficient means for controlling sheets advanced by a tape conveyer, and that while the invention has been shown and described in association with a sheet feeder for printing presses and the like, it will be readily apparent that it is applicable to any situation where it is desired to hold a sheet down onto a tape or belt conveyer.

What I claim as my invention is:

1. In a sheet feeder for printing presses and kindred machines, an endless fabric conveyer to present sheets individually to the press, a suction cup beneath the top stretch of the conveyer having a port closed by the conveyer so that the effect of vacuum within the cup is transmitted to a sheet disposed on the conveyer through the pores of the conveyer to hold the sheet down onto the conveyer, and means extending transversely of the conveyer and adjustable longitudinally thereof to mount said suction cup.

'2. In a sheet feeder, the combination of a slow moving endless tape conveyer arranged to present sheets slowly to the front guides of a printing press or other kindred machine, a fast moving endless conveyer having sheet grippers and arranged so that its lower stretch overlies and is substantially parallel with the top of the slow moving tape conveyer to carry sheets entirely over the tape conveyer whereby upon release of the sheets so carried upon opening of the grippers, the sheets drop fiatwise onto the slow moving tape conveyer, and suction means acting through the slow moving tape conveyer to hold the sheets thereon in the position in which they are dropped from the fast moving conveyer so as to insure proper presentation of the sheets to the front guides. I

FRANK R. BELLUCHE.

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