DD140551A1 - PRESSING BAR FOR CUTTING MACHINES FOR PAPER, PAPER OR THE SIMILAR - Google Patents

Description

Title of the invention

Press bar 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 bar on cutting machines for paper, cardboard od. Like., With which the material to be cut is immovably pressed during the cutting process on the cutting table.

Characteristic of known technical solutions In the case of cutting machines of the type mentioned, the occupational safety requirement is to shield the area in which the blade moves from the initiation of the cut to the average of the stack of cuts before any intervention. This requirement is realized by the arrangement of light barriers. When a light beam is interrupted as a result of an intervention in the protected area, the knife movement is immediately decelerated and the knife remains in the position held at the time the braking is completed. At the same time moving up to the top of the Schneidgutstapel or * on the cutting table leading the blade hydraulically driven pressure bar moves back to its upper position, so that now the knife edge is free and is a source of danger for serious injury.

To avoid this deficiency so far only one solution has become known, which consists in the control aali

the Preßbalkenantriebes is taken over after its separate, independent of the knife drive Einschaltang of a cam connected to the knife drive, such that on the one hand, the blade movement only after a period of time that corresponds to the duration of the full Preßbalkenhub and on the other hand, when interrupting the knife drive within a certain , already covered travel distance of the Preßbalkenantrieb is not stopped, but remains turned on, whereby it is achieved that the pressure bar remains on the stack of products or on the cutting table b-is to complete the cutting process.

This solution is disadvantageous because when interrupting the knife drive in the phase in which the knife is in its upper stroke, the press bar moves back to its uppermost position, so that the knife edge then protrudes under the press bar and a great danger represents the operator. In addition, there is still the defect that the delayed activation of the knife drive a relatively long time for .Absolvierung a working cycle is required and thus the productivity of the cutting machine is adversely affected.

Object of the invention

The invention aims to provide a Preßbalkenantrieb for cutting machines, which can be produced with little effort and still offers the operator the greatest possible security against injury when taking under the shutdown due to interruption of the knife drive knife. ·

.Development of the essence of the invention

The invention has for its object to provide a Preßbalkenantrieb for cutting machines, which is controlled so that when interrupting the knife drive before placing the Preßbalkens on the Schneidgutstapel or on the cutting table, the Preßbalkenunterkante • always protruding relative to the knife edge or, the

on the stack of cutting stock or on the cutting table mounted pressing bar in the pressing position, remains ..

According to the invention the object in a press bar drive for cutting machines for paper, cardboard od. Like., Which consists of a pressure medium feed pump, a control unit and a press cylinder, achieved in that hydraulically actuated controls are provided in the hydraulic system, which ensure that the * Preßbalken to for placing on the Schneidguiistapel or on the cutting table when interrupting the knife drive always · such a position innehat that the knife edge opposite; 75 of the Preßbalkenunterkante is recessed and remains on the stack of cutting material or on the cutting table patch press bar in the pressing position.

As a hydraulically operated controls either a directional control valve or arranged in the pressure chamber and cooperating with him oil pressure switch are provided.

-Ausführungsbeispiel

The invention will be explained in more detail below on two .Execution examples. In the accompanying drawings show:

Fig. 1ί the scheme of Preßbalkenantriebes arranged in the ) pressure line directional control valve

Fig. 2: the scheme of the drive of pressure bar and blade carrier in an exploded view with built-in pressure line oil pressure switch.

According to Eig. 1, a cutting machine has a knife carrier 1, a press bar 2, a protective grid barrier 3 ^m, control unit 4, a control device 5 for controlling the press bar and knife movement, a hydraulic drive for the press bar 2, consisting of a control unit S 1. a pressure medium pump 7? a pressure medium container 8, a pressing cylinder 9> a directional control valve 10, actuators 11 and 12 and lines I3 and 14.

I .1

The operation of this cutting machine is that upon actuation of the control member 5, the press bar 2 and bitesserträger 1 move in the direction of the cut material stack 15 and cutting table 16. When intervention in the protective area of the protective barrier 3 is carried out by the control unit 4 or upon interruption of the operation of the control member 5 by this the braking and stopping of the blade carrier. 1

At the same time either the control unit 4 or the control member 5 via the control unit 11, the inventively provided directional control valve 10 reversed so that the downward movement of the Preßbalkens 2, the forcibly against the blade carrier 1 has a flow is stopped by the lines Ί3 and 14 locked become. This ensures that the press bar 2 maintains its own at the time of interruption of the knife drive position.

In Fig. 2, the successively arranged blade carrier 1 and the press bar 2 are shown side by side. The drive 'of the knife carrier 1 is carried out by a drive motor, not shown, via a crankshaft 17 and hinged thereto Meßerträgerzugstange 18. The knife carrier 1 is on sliding blocks 19, which are arranged in the machine body, not shown, out. On the cutting table 16 a cut material 15 is provided. For driving the pressure bar 2 is a pressing cylinder 9, which is acted upon by a pressure medium pump 7 _5, a control unit 6 and line I3 from a pressure medium container 8 with a pressure medium provided. The pressing cylinder 9 is connected via levers 20 and tie rods 21 to the pressing bar 2. A arranged on the machine body guard rail 3 is included with its control unit 4 so in the control of the blade movement that at

Intervention in their protection range, the knife movement is stopped. In the line I3 of the pressing cylinder 9, an oil pressure switch 29 is arranged, with 'a relay with the normally closed contacts 22 and 23 and the contacts 24; 2535 25; 26; 27 is in operative connection.

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The mode of action of this solution according to the invention is the following:

After actuation of the control element 5 »which contains in a known manner a Zweihandeinrückung and a fully automatic, is via djLe normally closed contacts 22; 23 of the relay 28 controls the control unit 11 and actuates the control unit 6, whereupon the press bar 2 lowers onto the stack of product 15 or onto the cutting table 16. After 'putting on the press bar 2 on the stack of products 15 and on the cutting table 16 in der'Leitung 13 the · pressure increases, after which the inventively provided oil pressure switch 29 is actuated when reaching a certain value, which in turn via the Kontakte'26; 27 of the relay 28 and magnetic coupling 30 initiates the movement of the blade carrier 1. This ensures that the blade movement does not begin until the pressure bar 2 is already seated on the stack of products 15 or on the cutting table 16. If now intervened in the protective area of the protective grid barrier 3 or the operation of the control member 5 is interrupted, the magnetic coupling 3O is de-energized via the control unit or the control member 5. The knife carrier movement is switched off while .der Preßbalken 2 via the contacts 24; 25 of the relay 28 is still held on the Schneidgutstapel 15 and on the cutting table 16. The upward movement of the Preßbalkens 2 takes place only after cutting through the stack of cutting material, or is when the press bar 2 is seated on the cutting table 16, after Durchlaufen.der. bottom dead position of the knife carrier 1 via the limit switch 31 j ^ qx is controlled in response to the crankshaft 17, via actuator 11; 12 and control unit 6 initiated.

Claims (3)

Brfindungsansprüche: 1. Preßbalkenantrieb for cutting machines for paper, cardboard or the like., Which consists of a pressure medium feed pump, a control unit and a Preßzylinde'r, characterized in that hydraulically actuated controls are provided in the hydraulic system, which ensure that the pressure bar (2) until placement on the stack of products (15) or on the cutting table (16) always has such a position when the knife drive is interrupted, that the knife edge is set back relative to the bottom edge of the press bar and on the cutting material stack (15) or on the cutting table (16) attached Preßbalken (2) remains in the pressed position. 2. Preßbalkenantrieb according to item 1, characterized in that a directional control valve (10) is provided as a control. 3 · Preßbalkenantrieb according to item 1, characterized in that an oil pressure switch (29) is provided as a control. f i. ' ¹