DE1101128B - Circular knife holder for paper cutting machines u. like - Google Patents

Description

GERMAN

The invention relates to a pneumatically operated circular knife holder for paper cutting machines, in which the circular knife held in a guide piece and running in ball bearings in lateral recesses of a frame-shaped, after the knife to open holder slides so that it is in Direction of the web is kept movable.

Such circular knives are arranged in groups on a traverse above the path to be cut, wherein the cutting pressure in known designs of this type by a between guide piece and Frame attached spring is generated. It has also been proposed that such circular knives be pneumatic to operate. In an arrangement of this type, the cutting roller is supporting and between two plates guided slide in a fixed connection with a flexible rod, which in turn is attached to a pneumatically operated piston is attached. The pneumatic pressure generating arrangement is thus in place outside of the individual knives and therefore requires additional space. Also is the familiar arrangement relatively complicated and therefore expensive to manufacture.

According to an older proposal for a hydraulically or pneumatically adjustable holder for rotating Squeeze knife, the pneumatic drive is moved directly into the squeeze knife holder by the Piston of a pressure housing is directly connected to the carrier of the Ouetsch knife and the pressure housing is flat, can-shaped and arranged such that it is with its narrow side parallel to the crushing knife axis. In this older proposal, the one in the crush knife holder located pressure housing has taken over the function of the well-known hydraulic cylinder. For this arrangement, however, a special piston is still necessary to seal it against the gaseous or liquid pressure medium must be made particularly carefully, since the loss of hydraulic fluid or compressed gas to relieve the knife or, in the case of liquids, to a Contamination of the material to be cut. The one for this purpose in the older proposal provided sealing sleeve does not meet these conditions with absolute certainty.

According to the invention it is therefore proposed, in such a knife holder, between the guide piece on the upper narrow side and the frame a known, preferably folded To arrange bellows made of elastic material for the transmission of the pneumatic pressure. This measure, in which an airtight elastic bellows acts directly and evenly on the entire surface of the guide piece, has the advantage that

Circular knife holder
for paper cutting machines etc.

Applicant:

Wilhelm Bilstein

Tool and machine factory,

Vilkerath via Overath

Erich-Winfried Schmitz-Helff, Darmstadt-Eberstadt,

and Wilhelm Bilstein, Vilkerath about Overath,

have been named as inventors

Special seals as in the known constructions for the transmission of the pressure in omission come. This results in an extremely space-saving construction, in which, however, the pneumatic Pressure effect is relatively large and losses are excluded. Furthermore, the maintenance Reduced to a minimum, because with a suitable choice of material, especially a plastic for the bellows, a practically unlimited service life with perfect density can be expected.

The use of an elastic hollow body which is changeable in shape by adjustable internal pressure is has already become known in a rolling device, in particular a pile crusher. The familiar arrangement provides that each work roll is supported by at least one pressure-loaded beam, whereby to avoid construction inaccuracies and theoretically possible deflections of the support beams elastic pressure transmission members, so-called cushions are proposed, the elasticity of which can be selected or is adjustable. In particular, hoses made of rubber, synthetic rubber, elastic plastic or thin-walled, resilient metal called that with a pneumatic Pressure source in connection. In contrast to the known arrangement in which the The task to be solved was a uniform pressure distribution over the entire length of a rolling device, So to achieve a relatively large machine, each must in the present invention Knife holder can be adjusted by itself by changing the pneumatic pressure accordingly, so that either the same pressures for all knife

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holders or, depending on the choice, different cutting pressures can be generated. Furthermore, the pneumatic pressure must also increase the force of the relief springs be overcome, which ■ to lift the weight of the cutting knife with guide piece are usually provided with such cutting knife holders and under their influence when the contact pressure is released, the knives are automatically lifted from the cutting roller. The difficulty with the invention thus consisted in the fact that circular knife holders are small The structure of the building acts and therefore a very specific one in a relatively very narrow space Pneumatics that generate pressure and maintain and operate safely can be accommodated had to, with considerable demands being made on the material from which the bellows is made. Surprisingly, it has now been shown that the proposal according to the invention eliminates the problem can be resolved in an impeccable manner.

In a further development of the inventive concept and to facilitate the sliding of the guide piece in the frame are between the two Lateral sliding surfaces of the guide piece and the frame balls introduced.

The knife axis is also mounted in a ball bearing ring, the knife axis being advantageous at the same time forms the inner ring of the ball bearing.

The guide piece itself is made according to the invention from injection molding, which makes the execution significantly cheaper.

In the drawing, an embodiment of the invention is illustrated, namely shows 1 shows the side view of the circular knife holder,

Fig. 2 is a vertical longitudinal section along the line I-I of Fig. 1,

Fig. 3 is a plan view of the knife holder according to Fig.l,

FIG. 4 shows a partial cross section through the frame along the line II-II of FIG. 1,

Fig. 5 shows a cross section through the knife holder, in which a ball bearing in the guide piece is built in,

Fig. 6 is a partial cross section through the knife holder, in which in the guide piece the Axis of the knife holder serves as a ball bearing ring.

The knife holder consists of the frame I ₁ which is too open on the knife side and in which a guide piece 2 with the knife 3 mounted therein slides. Between the upper part 'of the guide piece and the frame, a bellows 4 made of flexible material is inserted, which is fed via a pipe 5 with compressed air. In the embodiment according to FIGS. 1 to 5, the knife itself is held in a ball bearing 6 which is injected into the knife holder 2, which is advantageously made of injection molding. In the embodiment according to FIG. 6, the knife axis is used? even as a ball bearing ring, so that the knife axis can be made stronger and still space is saved. In the embodiment according to FIG. 4, balls 8 are provided between the guide piece and the frame in order to reduce friction.

Claims (4)

Patent claims: 1. Pneumatically operated circular knife holder for paper cutting machines, in which the in Circular knives held in a guide piece and running in ball bearings in lateral recesses a frame-shaped, after the knife to open holder slides, characterized in that between the guide piece (2) on its upper narrow side and the frame (1) a known per se, preferably folded bellows made of elastically deformable material for the transmission of the pneumatic pressure is arranged. 2. Circular knife holder ¹ according to claim 1, characterized in that balls (8) are introduced between the two lateral sliding surfaces of the guide piece and the frame (1). 3. Circular knife holder according to claim 1, characterized in that the knife axis (7) at the same time forms the inner ring of the ball bearing. 4. circular knife holder according to claim 1 to 3, characterized in that the guide piece (2) of the circular knife (3) consists of injection molding. Considered publications:
German Patent Nos. 1 024 341, 918 676; U.S. Patent No. 2,802,528. Legacy Patents Considered:
German Patent No. 1 072 878. 1 sheet of drawings © 109 528/430 2.61