DE2947426A1 - PRESS BAR DRIVE FOR CUTTING MACHINES FOR PAPER, CARDBOARD OR THE LIKE - Google Patents

Description

Title of the invention

Press beam drive for cutting machines for paper, cardboard or the like.

Field of application of the invention

The invention relates to a hydraulic drive for the press beam on cutting machines for paper, cardboard or od. Like. With which the material to be cut is immovably pressed on the cutting table during the cutting process.

Characteristics of the known technical solutions In the case of cutting machines of the type mentioned, there is a requirement for occupational health and safety, the area in which the knife moves, from the initiation of the cut to the Shield the cross section of the stack of items to be cut from any intervention. This requirement is made by the an-order realized by light curtains. When a light beam is interrupted as a result of an intervention in the protection area is immediately braked and the knife remains in the position it was in at the time the braking was ended. Simultaneously the one moving ahead of the knife until it is placed on the stack of items to be cut or on the cutting table hydraulically driven press beam back in its upper position, so that now the knife edge is free and is a source of danger for serious injury.

To avoid this deficiency, only one solution has so far become known, which is that the control

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of the press beam drive after its separate, independent of the * .; esser drive, one with your I.Iesser drive connected cam is taken over, in such a way, that on the one hand the knife movement begins only after a period of time which corresponds to the running time for the full press beam stroke and on the other hand, if the knife drive is interrupted within a certain, already covered I.Iesserweg the press beam drive is not stopped, but remains switched on, whereby it is achieved that the Press bar on the stack of items to be cut or on the cutting table persists until the end of the cutting process.

This solution is disadvantageous because if the I.Iesser drive is interrupted in the phase in which the knife is in its upper stroke area, the press beam is moved back into its uppermost position, so that the knife edge then protrudes under the press beam and represents a great danger to the operator. aside from that 4-5 there is still the shortcoming that due to the delayed activation of the knife drive a relatively long time is required to complete a work cycle and thus the productivity of the cutting machine is adversely affected.

Object of the invention

The aim of the invention is to provide a press beam drive to create for cutting machines, which can be produced with little effort and still the operator the greatest possible safety against bodily harm when reaching under the due to the interruption of the knife drive shut down knife offers.

Statement of the essence of the invention The invention is based on the object of a press beam drive to create for cutting machines, which is controlled so that when the knife drive is interrupted Before placing the press beam on the stack of items to be cut or on the cutting table, the lower edge of the press beam always protrudes from the knife edge or the one on ciew

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good stack or press beams placed on the cutting table remains in the pressed position.

According to the invention, the object is achieved with a press beam drive for cutting machines for paper, cardboard or the like, consisting of a pressure medium feed pump, a control unit and a press cylinder is, achieved in that a hydraulically operated, with a hydraulic system Control unit and a control member in connection as well as acting on the control unit or the Control element, the lines blocking control element is arranged in the form of a directional control valve.

Instead of the directional valve, according to the invention, as a control element an oil pressure switch can also be arranged.

Embodiment

The invention is to be explained in more detail below using two exemplary embodiments. In the accompanying drawings demonstrate:

Fig. 1: The scheme of the press beam drive with the directional control valve arranged in the pressure line

Fig. 2: The diagram of the drive of the press beam and knife carrier in an exploded view with in the pressure line built-in oil pressure switch.

According to FIG. 1, a cutting machine has a knife carrier 1, a press beam 2, a protective gate 3 with control unit 4, a control member 5 for controlling the Press blade and knife movement, a hydraulic drive for press beam 2, consisting of a control unit 6, a pressure medium pump 7 »a pressure medium container 8, a press cylinder 9, a directional control valve 10, actuators 11 and 12 and lines 13 and 14.

This cutting machine works as follows:

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This cutting machine works as follows: that upon actuation of the control member 5 press bar 2 and knife carrier 1 in the direction of the stack of items to be cut 15 or cutting table 16 move. In the event of intervention in the protection area of the protective grating barrier 3 takes place through the control unit 4 or when the actuation of the control member 5 is interrupted by this braking and Shutting down the knife carrier 1.

At the same time, either by the control unit 4 or the control member 5 via the actuating unit 11, according to the invention provided directional valve 10 reversed so that the downward movement of the press beam 2, forcibly opposite the knife carrier 1 has a lead, is stopped by the lines 13 and 14 are blocked. Through this it is achieved that the press beam 2 is in its position at the time of the interruption of the knife drive maintains.

In Fig. 2 are the knife carriers arranged one behind the other 1 and the press beam 2 shown side by side. The knife carrier 1 is driven by a not shown Drive motor from a crankshaft 17 and knife carrier pull rod 18 hinged to it. The knife carrier 1 is guided on sliding blocks 19, which are arranged in the machine body, not shown. On the Cutting table 16 has a stack of items to be cut 15 ready. For the drive of the press beam 2 is a press cylinder 9> via a pressure medium pump 7 »a control unit 6 and line 13 from a pressure medium container 8 with a Pressure medium is applied, is provided. The press cylinder 9 is connected to the press beam via levers 20 and tie rods 21 2 connected. A protective grating barrier 3 arranged on the machine body is like this with its control unit 4 included in the control of the knife movement that the knife movement is stopped when their protection area is interfered with will. In the line 13 of the press cylinder 9, an oil pressure switch 29 is arranged with a relay with the normally closed contacts 22 and 23 and the contacts 24j 25? 26; 27 in

ORIGINAL INSPECTED

The mode of action of this solution according to the invention The task is as follows:

After actuation of the control member 51 in a known manner contains a two-hand indentation and a fully automatic machine, is on the normally closed contacts 22; 23 of the relay 28 actuates the actuating unit 11 and actuates the control unit 6, whereupon the press beam 2 is lowered onto the stack of items to be cut 15 or onto the cutting table 16. After putting on of the press beam 2 on the stack of items to be cut 15 or on the cutting table 16, the pressure increases in line 13, after which, when a certain value is reached, the oil pressure switch 29 provided according to the invention is actuated, which in turn via the contacts 26; 27 of the relay 28 and magnetic coupling 30 the movement of the knife carrier 1 initiates. This ensures that the knife movement only begins when the press beam 2 is already on the The stack of items to be cut 15 or is seated on the cutting table 16. It is now in the protection area of the protective grating barrier 3 intervened or the actuation of the control organ 5 interrupted, the magnetic coupling 30 is de-energized via the control unit or the control element 5. The knife carrier movement is switched off while the press beam 2 via the contacts 24; 25 of relay 28 continues is held on the stack of items to be cut 15 or on the cutting table 16. The upward movement of the press beam 2 takes place only after cutting through the stack of items to be cut, or is when the press beam 2 on the Cutting table 16 sits, after passing through the lower dead position of the knife carrier 1 over the limit switch 31, the is controlled as a function of the crankshaft 17, via actuating unit 11; 12 and control unit 6 initiated.

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Claims (2)

Invention claims: Θ Press beam drive for cutting machines for paper, Cardboard or the like, which comes from a pressure medium feed pump, consists of a control unit and a press cylinder, characterized in that deΓ ii ■ hydraulic system a hydraulic actuated, with a control unit (4) and a control member (5) in connection with Action on the control unit (4) or the control member (50 the lines (13; 14) blocking control element is arranged in the form of a 'Vegeventils (10). 2. Press beam drive according to point 1, characterized in that that an oil pressure switch (29) is arranged as a control element. 030025/0579 ORK3INAL INSPECTED