EP1658939B1 - Circular blade holder with guard - Google Patents

Abstract

The guard has a spring unit (10) as a latch to hold the secondary hand guard (9) in a lower protecting position. An actuator supports a circular knife (5) in a knife head (4) between an upper resting position and a lower cutting position. The circular knife is surrounded by a primary hand guard, which is attached on the actuator. The actuator releases the latch when it moves from a cutting position to a resting position.

Description

The present invention relates to a circular knife holder with at least one bearing of a circular blade, an actuator for changing the position of the circular blade and at least one hand guard, which is arranged relative to the circular blade relatively movable with the features of claim 1, and a method according to claim 13. Such Knife holder is in EP 0 562 454 A1 disclosed.

In the GM 200 11 320 a hand guard is described, which is firmly connected to a main body of a pneumatic scissors blade holder and the cutter head completely surrounds and has an opening through which the circular blade with its cutting edge can be brought out into the cutting position. This construction is rigid and has only a protective function in rest position.

In the filed GM 20 2004 017 934.2 a hand guard is described, which as a unitary, consisting essentially of two interconnected boards component on the base manually displaceable in the lower tool and an upper fixed stop for the rest position and a lower fixed stop for the cutting position is attached.

In the DE-PS 31 46 123 a circular knife holder is described, which has a substantially consisting of a component, closed only open at the bottom hand protection. A major disadvantage in both rest position and in cutting position is that the hand guard escapes upwards and releases the knife edge as soon as the worker encounters them during adjustment work.

According to the further prior art, therefore, several proposals for a contrast inevitably closed hand guard are known. Both in the DE-PS 37 12 078 , in the DE-PS 38 41 576 as well as in the G 90 12 926.1 is a circular segment-shaped cutout on a fixed primary handguard assigned to this segment or segments adapted as secondary handguard, this being swung away by various drives and devices, -rotated, -folded, or-pushed. Only in the rest position in this case a secure protection against the circular blade cutting edge is guaranteed. In the lower cutting position, however, this is more or less free in the area of the cutout.

In DE-GM 90 13 761 a secondary handguard is described, which arranged as a in a plane parallel to the circular blade, with the main body of the circular knife holder fixedly connected, plate-like or partially plate-like element is formed, which projects beyond the knife edge in the direction counter tool and additionally angled at the lower edge and here can have an opening for the passage of the circular blade cutting and / or hinged or swung. However, the secondary handguard is fixed in the direction of the lower tool, so that the circular blade and the primary handguard moves past it into the lower cutting position. Again, the circular knife edge is more or less free.

The object of the present invention is to reduce the risk of accidents when using a circular blade.

This object is achieved with a circular knife holder with the features of claim 1 and with a method having the features of claim 13. Further advantageous embodiments and further developments are specified in the respective subclaims.

Proposed is a circular knife holder with at least one bearing of a circular blade, a hand guard and an actuator with a translational position change of the circular blade and the hand guard, which is arranged relative to the circular blade relatively movable. It is provided for translational position change at least one additional translational guide along which the hand guard is automatically feasible relative to the circular blade from a first end position to a second end position using a separately arranged actuator positioning element and at least the actuator is arranged on the circular knife holder by means of a Force on the hand guard along the translational guide in the direction of a working position of the hand guard can be impressed, which presses the hand guard against a stop as an end position, so that by means of the adjusting pressure element, a relative movement between the circular blade and hand protection is effected. In this case, the circular blade is movable out of a protection of the hand guard in its working position. The translational guidance ensures that the handguard is guided straight when its relative movement is being exerted. An entanglement or terminals is thus excluded in this safety function. Incidentally, a sequence of movements is also simplified as a whole and the positioning adjustments necessary for setting a position of the hand guard or for a position of the circular blade are additionally improved. In particular, the translational guidance takes place over the entire path from the first end position to the second end position. The actuator is also active in particular also from the first end position to the second end position, so that preferably solely due to the applied Force, in particular pressure force by the actuator, the relative movement between the hand guard and circular blade is executed. The translational guide can be arranged, for example, directly on the hand guard. However, it can also be provided on the actuator. The actuator can be performed, for example, pneumatically, electrically or hydraulically. Likewise, mixtures of these different drive types are possible. Furthermore, there is the possibility that an actuator is also designed mechanically, with a place can be done manually. The control element can also be designed, for example, pneumatically, electrically or hydraulically as well as mechanically. For example, the actuator is driven differently than the actuator. This is accompanied by a reliability.

Another reliability results if, in addition to the acting actuator also has the opportunity to exploit the gravity can. According to one embodiment, a fit is provided on elements sliding past one another, in particular the translational guide, which allows sliding only under the effect of gravitational pull, provided that the actuating element would fail. For this purpose, it may be provided that a coupling with the actuating element would be automatically interrupted in such a case. A further embodiment provides that the fit is such that a frictional interruption of a movement occurs when the actuating element fails.

In the following, the design of the actuating element will be explained in more detail with reference to a pressure element. In addition to the use of a pressure element, however, it is also possible to use a tension element. This has the effect of using a tensile force for the relative movement or for the force acting against the stop. The tension element can be arranged at different positions as well as the pressure element. Incidentally, combinations of tension and compression element can form the actuator. Just as different embodiments can be used for the pressure element, this also applies to the tension element.

The pressure element can impose a constant pressure according to a first embodiment. According to a further embodiment, the pressure element can impose a changing pressure. Preferably, the pressure is adjustable. A further development provides that the pressure element is controlled hydraulically or pneumatically. Another development provides that the pressure element has a mechanical pressure generation. An embodiment provides that the pressure element has at least one spring, in particular a spiral spring. This is designed as a compression spring and can be used in the circular knife holder form the pressure element.

In addition to the arrangement of a single printing element, there is still the possibility that several printing elements are provided. According to one embodiment, it is provided that two pressure elements are arranged parallel to each other. By a distribution of the two pressure elements such that a uniform total pressure can be impressed, it is avoided in the translational guide that transverse forces occur in the guide, which could otherwise cause a possible jamming.

It is preferably provided that at least one first pressure element has a change in length which runs parallel to the translatory guide. According to another embodiment, it is provided that at least one first pressure element has a change in length which runs along an extension of the translatory guide. Again, an additional embodiment has at least one pressure element with a change in length, in which this extends within the translational guide.

According to one embodiment, it is provided that at least one of the pressure elements is connected to the hand guard and imprints the pressure force directly on the hand guard. In particular, however, several pressure elements may be connected to the hand guard to impart the pressure force. A further development provides that the pressure force on the hand guard is impressed on the hand guard, for example, via a main body of the circular knife holder on which the actuator is arranged. A further embodiment provides that the pressure force is impressed on a support on the hand guard itself on a part of the hand guard. The latter can be carried out in particular by an at least two-part hand protection, which can preferably be distinguished into a primary hand protection and a secondary hand protection. There is also the possibility that the pressure force receives a support on the actuator.

For an accuracy of the guide, it is advantageous if the translational guide has a first guide track and a second guide track, which are arranged parallel to each other. Preferably, the first guide track and the second guide track are similar, in particular also running at the same height. However, the first and second guideways can also be different, for example displaced relative to one another with respect to their respective arrangement height. It is also possible to use more than two guideways. The guideways are according to one embodiment, the only guides along the translational relative movement between circular blade and hand protection. In particular, these guideways and corresponding guide elements extending in the guideways can thus have matched geometries which, on the one hand, permit close tolerance and, on the other hand, no jamming. According to another embodiment, it is provided that at least one second guide is provided, via which at least one stop for the hand guard and / or the circular blade or the actuator is provided.

Preferably, the circular knife holder has a design in which the hand guard has at least one coupling point with a component of the circular knife holder, wherein the Koppetstette causes a limitation of relative movement between the hand guard and circular blade along the translational guide. The coupling point, for example, form a stop. The stop, for example, can take effect when the hand guard has taken a first and / or second end position. The coupling point can be integrated in the translational guide as well as provided independently of this. The translational guide may have a limitation for a movement of the circular blade or the hand guard, for example by a positive stop.

The circular knife holder can be used, for example, in a scissors cutting system as an upper tool with an upper knife, to which a slot cutter or a groove cutter box is arranged opposite as a lower tool. There is also the possibility that the circular knife holder is used in a squeeze-cutting system in which the circular knife holder has a crimping knife which serves as an upper tool and is arranged opposite a lower tool. The lower tool is in particular a shaft with a hard, preferably hardened surface.

In particular, the circular knife holder is set such that in a longitudinal cutting device the hand guard forms an open, vertical gap with an opposing component of the longitudinal cutting device in a moved position of the circular knife holder for engagement with a material to be cut lengthwise, which is smaller than 5 mm. The particular alone translational guide at least in one area to the working position of the circular blade can be avoided with appropriate provision of the hand guard that an operator can get between the top and bottom roller or the top blade and the bottom blade with his fingers. The translational guide allows a vertical feed movement to the opposite component, in particular a rotary roller is executable. In particular, the direction of travel perpendicular to the shaft or axis passes directly through a Longitudinal axis of the shaft or bushing through. However, there is the possibility that the translational travel direction of the circular blade holder is arranged for the circular blade such that a feed movement offset from the longitudinal axis and thus inclined thereto extends. In particular, however, the circular knife holder and thus also the circular blade is arranged parallel to a vertical cross section through the shaft longitudinal axis or bushing longitudinal axis. However, according to another embodiment, the circular knife holder can also be adjusted to be inclined, so that the circular blade also receives an inclination relative to the longitudinal axis of the shaft or socket.

The open, vertical gap that forms between the handguard and the opposing component when the circular blade is in a working position is intended to minimize the risk of injury. Preferably, the resulting gap is at most 4 mm or less high. In this way, it can be ensured that, on the one hand, finger injuries due to accidental ringing between the shaft or bush and the cutting blade are avoided. On the other hand, the gap height allows the insertion of material to be cut. In particular, when setting up the longitudinal cutting device, the feeding of the material into the gap can be ensured without the fingers holding the material themselves being able to get into a cutting area.

Preferably, the circular knife holder is provided in a region of at least one of the end positions with a barrier which prevents a relative displacement between hand guard and circular blade. For example, the lock is designed as a lock. In particular, when the barrier is arranged in the region of the working position of the circular blade prevents access to the cutting area is made possible by manually pushing up the hand guard. Only by lifting the lock, such as a mechanical lock, something would be possible. In order to avoid incorrect operation here, at least the lock can be equipped with a safety device. If the lock is overcome without authorization, for example by forcefully pushing the hand guard, a safety function can be triggered. The safety function can be carried out, for example, by stopping the longitudinal cutting device, by starting the circular blade and / or by another automatic function of the circular blade holder or the longitudinal cutting device which deactivates a potential risk of injury. It is preferably provided that a safety device is arranged at least on the circular knife holder, which triggers when the hand guard abuts against an obstacle not provided. In this way, for example, avoided when lowering the circular blade and simultaneously lowering the hand guard an object may come into contact with the cutting area of the circular blade, for example, if the hand guard is held or hit an obstacle and thereby the circular blade moved in its traversing movement and finally reachable with the cutting area.

Furthermore, the circular blade holder preferably has an adjustment with which a position of a reground circular blade is adjustable relative to a position for hand protection. In this way it is possible, for example, to be able to set a constant safety distance even with a changing diameter of reground circular knives. The adjustment may provide that the relative position of circular blade bearing is adjustable to a position of the arrangement of the hand guard. Another embodiment provides, for example, that a circular knife bearing relative to the actuator is variable. In this way, the hand guard can remain firmly positioned relative to the actuator. An adjustment is then carried out with the aid of the actuator. However, the adjustment can also rely on other components of the circular knife holder.

According to one embodiment, it is provided that the adjustment of the hand guard in particular must be done only once. If subsequently the circular knives are reground, replaced with new ones or removed and reinserted, the protective function remains due to the first adjustment. The position of the circular blade is therefore also adjustable so that hand guard and circular blade can be arranged independently of each other and in particular adjustable. After such initial adjustment of the hand guard no subsequent readjustment is necessary. However, the adjustment can be checked from time to time. For this purpose, an automatic monitoring or a display can be provided, from which it can be read that a readjustment is necessary.

According to a further aspect of the invention, a method for protecting an operator of a longitudinal cutting device is proposed, in which at least one circular blade is moved in a working position for engaging in a longitudinal path and a translational relative movement between the hand guard and circular blade is performed only at the time when the hand guard has formed a predetermined safety gap with an opposing component of the circular blade and moves the circular blade in its working position. In this way, it is ensured that the circular blade can not reach beyond the hand guard until the safety gap, which prevents the operator's fingers from penetrating, has been formed. Until this Time is the circular blade not over the hand protection protruding, in particular, it is not along its entire circumference diameter over. It is preferably provided that, when the safety gap is formed, only a partial circumference of the circular blade can emerge beyond the hand guard in order to engage a longitudinal track to be cut. Preferably, the hand guard is locked at a time when the circular blade moves into the working position for engagement with a longitudinal track. The locking is preferably carried out at the latest in an end position for the hand guard, but can also be triggered when an area of the end position is reached. For example, for this purpose a pawl can be overcome by the hand guard itself or a component connected to the hand guard. The pawl locks a return movement of the hand guard. The pawl can only be removed again by an authorized adjustment from the blocking area and thus allow a displacement of the hand guard against the circular blade. Preferably, a locking of the hand guard is only canceled at a time when the circular blade is fully retracted again into the hand guard. A further reduction of an accident risk results when the hand guard is permanently pressurized in the direction of the working position after leaving a rest position. In particular, the pressurization can be carried out such that a minimum pressure is provided on the hand guard. This minimum protection is preferably so great that an average operator, with a usual, by a hand applied force is not able to move the hand guard in an inadmissible way manually. The hand guard or an adjacent component is preferably equipped with a sensor, in particular a pressure sensor. If a counter pressure is detected on the hand guard, an automatic interruption of the process of the circular blade can be initiated.

The hand guard according to one embodiment is a single component. This can be composed of several components. The hand guard is preferably dimensioned such that it can accommodate the entire circular blade and covered laterally. In particular, the hand guard may have a cavity in which the circular blade is retractable, in particular completely retractable. The cavity is preferably completely surrounded laterally, so that the circular blade is housed. In one embodiment, it is provided that a slot arrangement is provided in this enclosure. Only through this slot arrangement, a partial circumference of the circular blade can fall outside the protective hood. For example, a shape of this protective hood can be predominantly round, in particular circular and preferably adapted to a shape of the circular blade. In particular, the shape of the protective hood is such that the circular blade is movable within this housing formed by the protective hood. For example The protective hood has an at least approximately circular geometry in its upper region. This is followed, for example, by a longitudinal extension, which is adapted from the dimension to the circular blade movable in the protective hood. In a lower region of the protective hood, it can preferably be adapted to a geometry on an opposing counter element, for example a roller or grooved bushing. In particular, a surface of the protective hood lying opposite the shaft or grooved bushing can have an at least approximately arcuate, in particular circular, course, within which an opening for a leakage of the circular blade is arranged. If the guard is multi-part, it can be provided that a lower geometry is interchangeable and thus adaptable to a respective opposite shaft or grooved bushing. Preferably, the surface of the protective hood opposite the shaft or grooved bush runs at least partially parallel to it.

According to one embodiment, it is provided that the hand guard essentially consists of laser-cut or punched sheet metal. According to another embodiment, it is provided that the hand guard consists of, for example, two interconnected boards, which form a cavity in which the circular blade is arranged.

In the following, various embodiments are exemplified. However, the features specified in each case are not limited to the individual embodiment. Rather, these features can also be used in other embodiments or with other features linked to further developments.

A first embodiment provides that the handguard as a unitary, consisting essentially of two interconnected boards existing component on the base body and / or on the actuator is slidably mounted in the direction of lower tool and is pressed by a biased drive spring permanently in the lower tool, where he in his upper guard position is held by the actuator and at the same time moved by the drive spring in its lower protective position to a fixed stop on the body, after which the actuator moves with circular knife further into the lower cutting position and the circular blade through a slot in the lower part of the handguard passes through and so lengthened to its final cutting position.

Another advantage is achieved by cushing the resulting pinch between the guard and lower tool.

A second embodiment provides that the hand guard is divided into a primary hand guard and a secondary hand guard. However, there is the possibility that the hand guard can be divided into even more than two relatively movable components. The second embodiment provides, for example, that the secondary handguard as a substantially one-piece component on the actuator is preferably slidably mounted on the primary handguard in the direction of the lower tool and permanently pressed in the direction of the lower tool via a prestressed drive spring, which is supported on the main body or preferably on the actuator he is held in its upper protective position by the actuator and this is simultaneously displaced by the drive spring in its lower protective position up to an adjustable fixed stop on the body and reaches its lower protective position with a constant safety distance to the counter tool, after which the actuator with circular blade in further moves the lower cutting position and the circular blade passes through a slot in the lower part of the secondary handguard and thus reaches its final cutting position. As "actuator" here are the rigidly attached components meant as guide rod or rods, traverse, knife head and primary hand guard. The secondary handguard consists essentially of a one-piece laser-cut or stamped sheet metal, which completely covers the circular segment-shaped cutout of the primary handguard, angled downwards and provided here with a slot for the knife passage and angled upwards for the depth stop.

Fig. 1

in beispielhafter Ausgestaltung einen pneumatischen Quetschmesserhalter mit Handschutz, bei dem wesentliche Funktionsteile grob vereinfacht in einer Ebene dargestellt sind, wobei ein Kreismesser mit einem Ursprungsdurchmesser in Ruheposition dargestellt ist, wobei der Handschutz in einer oberen Schutzposition angeordnet ist,

Fig. 2

die Ausgestaltung aus Fig. 1, wobei jedoch das Kreismesser sich nun in Schneidposition befindet und der Handschutz in eine untere Schutzposition verfahren worden ist,

Fig. 3

eine Anordnung entsprechend Fig. 2, wobei jedoch anstatt eines Kreismessers mit ursprünglichem Durchmesser ein nachgeschliffenes Kreismesser mit verringertem Durchmesser in Schneidposition dargestellt ist,

Fig. 4

die Seitenansicht eines einsäulig geführten pneumatischen Scherenschnittmesserhalters mit Kreismesser in Ruheposition und Sekundärhandschutz in oberer Schutzposition,

Fig. 5

den Messerhalter aus Fig. 4 in Vorderansicht,

Fig. 6

den Messerhalter aus Fig. 5 mit Kreismesser in Schneidposition und Sekundärhandschutz in unterer Schutzposition,

Fig. 7

einen Ausschnitt aus Fig. 4 mit einer anderen Antriebsvariante für den Sekundärhandschutz,

Fig. 8

die perspektivische Ansicht eines doppelsäulig geführten pneumatischen Scherenschnittmesserhalters messerseitig von vorne mit Kreismesser in Ruheposition und Sekundärhandschutz in oberer Schutzposition,

Fig. 9

den Messerhalter aus Fig. 8 in perspektivischer Ansicht traversenseitig von vorne mit Kreismesser in Ruheposition und Sekundärhandschutz in oberer Schutzposition,

Fig. 10

den Messerhalter aus Fig. 8 mit Kreismesser in Schneidposition und Sekundärhandschutz in unterer Schutzposition,

Fig. 11

den Sekundärhandschutz als einteiliges Bauteil in perspektivischer Darstellung,

Fig. 12

einen Sekundärhandschutz mit einer Sperre,

Fig. 13

die Sperre aus Fig. 12,

Fig. 14

eine weitere Ausgestaltung einer Justagemöglichkeit mit einem Kreismesser in einer ersten Position, und

Fig. 15

der Kreismesserhalter aus Fig. 14 mit dem Kreismesser in einer zweiten Position.

Further advantageous embodiments and developments will become apparent from the following drawings. However, the embodiments shown there are not to be construed restrictively. Rather, the respective features are given by way of example and can be linked to the above-mentioned as well as from other figures of the drawing features to developments. Show it:

Fig. 1

in an exemplary embodiment, a pneumatic crushing knife holder with hand protection, in which essential functional parts are shown roughly simplified in a plane, wherein a circular blade is shown with an original diameter in the rest position, wherein the hand guard is disposed in an upper protective position,

Fig. 2

the embodiment Fig. 1 but with the circular knife now in the cutting position and the hand guard moved to a lower protective position,

Fig. 3

an arrangement accordingly Fig. 2 in which, however, instead of a circular knife of original diameter, a reground circular knife of reduced diameter is shown in the cutting position,

Fig. 4

the side view of a pneumatic guided scissors blade holder with circular blade in rest position and secondary handguard in upper protection position,

Fig. 5

off the knife holder Fig. 4 in front view,

Fig. 6

off the knife holder Fig. 5 with circular knife in cutting position and secondary hand guard in lower protective position,

Fig. 7

a section from Fig. 4 with another drive variant for secondary hand protection,

Fig. 8

the perspective view of a double-headed pneumatic scissors cutting blade holder on the knife side from the front with circular blade in rest position and secondary hand protection in the upper protection position,

Fig. 9

off the knife holder Fig. 8 in perspective view from the front on the traverse side with circular blade in rest position and secondary hand protection in upper protective position,

Fig. 10

off the knife holder Fig. 8 with circular knife in cutting position and secondary hand guard in lower protective position,

Fig. 11

the secondary handguard as a one-piece component in perspective view,

Fig. 12

a secondary handguard with a lock,

Fig. 13

the lock off Fig. 12 .

Fig. 14

a further embodiment of a Justagemöglichkeit with a circular blade in a first position, and

Fig. 15

the circular knife holder Fig. 14 with the circular knife in a second position.

Fig. 1 shows a circular knife holder with a hand guard 3 in an upper protective position and with a new, not yet reground circular blade 5, which has the diameter D-max, in a rest position. A piston 6 of an actuator 2 with a cutter head 4 and the circular blade 5 mounted thereon is also located in a not shown in detail piston / cylinder unit 7 with a return spring in an upper end position, ie in a raised position of a lower tool 16. The hand guard 3 as a single component is at guide slots 9.1 / 2 and guide pins 10.1 / 2 and 11.1 / 2 on a base 1 of the circular knife holder by a driving pin 12 on the actuator 2 and a slot 13 on the hand guard against a spring force of two drive springs 14.1 / 2 as a working position in a held in the upper protective position. The guide slots 9.1 and 9.2 with the guide pins 10.1, 10.2 and 11.1, 11.2 form a translational guide for the relative movement between the hand guard 3 and the circular blade. 5

Fig. 2 shows the circular knife holder with hand guard 3 in the lower protective position and also with new, not yet reground circular blade 5 in the cutting position. The piston of the actuator with cutter head and circular knife mounted thereon is located after reaching a stroke H-min in a cutting position as a working position. The hand guard is located by the biased drive springs 14.1 / 2 against the fixed stops 10.1 / 2 in the lower guard position after covering a constant distance S-fix.

Fig. 3 shows the circular knife holder Fig. 1 with hand guard 3 in the lower protection position and now with reground circular blade 5. The position of actuator 2 with cutter head 4 and the circular blade 5 mounted thereon and the hand guard 3 otherwise corresponds to Fig. 2 with the difference that the actuator has covered the larger stroke H-max to compensate for the smaller diameter of the circular knife D-min.

The movement of Fig. 1 to Fig. 2 is as follows: As soon as the actuator 2 moves with cutter head 4 and 5 mounted circular blade toward the lower tool 16, the hand guard 3 is simultaneously moved by the spring force of the drive springs 14 up to the fixed attachment 10 on the base body 1. Thus, the hand guard has 3 after covering the fixed distance S-fix reached its lower protective position by a constant safety distance "a" is maintained. Only then follows the passage of the circular blade 5 through the slot 15 in the lower region of the hand guard 3, which is here in the form of a protective cover, to the lower tool 16, after which the actuator has covered the stroke H-min.

The movement of Fig. 1 to Fig. 3 takes place in the same way as from Fig. 1 to Fig. 2 only with the difference that the actuator has covered the stroke H-max.

In the reverse order of cutting in the rest position, the circular blade 5 first enters the protective hood as soon as the actuator moves to the rest position. Only then is the hand guard from the driving pin 12 on the actuator 2 and slot 13, which additionally has a guiding function, pushed on the hand guard 3 against the spring force of the drive springs simultaneously in the upper protective position.

In particular, in narrow-built circular blade holders, the boards of the hand guard can be connected by spacers with each other, which are then guided in slots in the body.

Instead of guide elements in the form of pins and slots, grooves with a spring, for example in the case of wider knife holders, are also used. can be used as a swivel tail guide.

The prestressed drive springs between the body and hand guard, as shown in the figures, or as a variant between actuator and hand guard can also be designed as a tension spring. Likewise, other types of spring can be used.

To increase the protective function, the supply air in the piston / cylinder unit for the actuator can be throttled, so that the passage of the circular blade after reaching the safety position of the hand guard relatively late and slow.

This can be further ensured by a positive control upon actuation of a control valve on the fixed stop of the hand guard by the further movement of the actuator is only released when the hand guard reaches the lower protection position and then the circular blade is pushed with adjustable time through the slot in the cutting position ,

The construction described here can also be used if the circular knife holder is equipped with razor blades instead of a circular knife, for example on a revolver.

The design principle is equally applicable to other actuators in the same way, e.g. the drive takes place in place of a piston / cylinder unit by an electric actuator.

In Fig. 4 is a pneumatic Scherenschnittmesserhalter with a one-column guided actuator shown in the side view, as he is generically described in the aforementioned writings with inevitably closed hand guard.

The actuator, which is guided and driven on a base body 17 is not shown in detail but only by its guide column 18 and is in its upper end position, i. in rest position. At the guide column 18 of the cutter head 21 is attached thereto with circular blade 20 and the primary hand guard 19 is attached.

On the base body 17 of the circular blade holder, a depth stop 23 with a fixed part 23a and adjusting screw 23b is fixed and an adjustable part 23c with slot 23d and angled stop 23e.

The secondary hand guard 22 is in the upper protective position and is guided and held in its guide slots 25.1 / 2 on the primary hand guard 19 via guide pins with head 26.1 / 2 and 27.1 / 2. The secondary hand guard 22 consists essentially of a one-piece, laser-cut or stamped sheet metal part with a circular segment-shaped section of the can-shaped primary hand guard 19 covering part and a lower bend 28 to the circular blade out with a passage slot 29 for the circular blade 20, and two the cutter head 21 and primary handguard attachment part 19a between cutter head 19 and primary handguard 19a is against the Abstützabwinklung 22b of the secondary handguard 22 a prestressed drive spring 24 mounted as a compression spring, the secondary handguard 22nd permanently pushes down. In the upper protective position of the secondary hand guard 22 is held by the driver and guide pins 26.1 / 2, the primary hand guard 19.

In Fig. 5 is the knife holder off Fig. 4 shown in front view and also shows the guide column 18 of the actuator with cutter head 21 and circular knife 20 stored thereon and primary hand guard 19 with mounting part 19a in rest position and the secondary hand guard 22 in the upper protective position.

On the base body 17 of the circular knife holder of the depth stop 23 with fixed part 23a and adjusting screw 23b is fixed and an adjustable part 23c with not visible here slot and angled stop 23e. The secondary hand guard 22 is guided and held in its guide slots, not visible here, on the primary hand guard 19 via upper driver and guide pins with head 26 and lower guide pins 27. The secondary hand guard 22 covers the cutout of the primary hand guard 19 downwards and protects the circular blade cutting edge 20 by the lower bend 29 with its passage slot 29 for the circular blade. Upwards, the secondary hand guard 22 is also provided with an angled portion 22a for the stop 23e. Between the cutter head 21 and the primary hand guard 19a against the Abstützabwinklung 22b of the secondary hand guard 22, the biased drive spring 24 is mounted as a compression spring.

In Fig. 6 is the knife holder according to Fig. 2 shown, only with the difference that the guide column 18 of the actuator with cutter head 21 and mounted thereon circular blade 20 and primary hand guard 19 are in the lower cutting position and the secondary hand guard 22 in lower protection position. The circular blade has passed through its slot 20 through the slot 25 in order to cooperate with the counter knife, not shown.

In Fig. 7 is a section of Fig. 1 shown with a drive variant for the secondary handguard 17 in the form of prestressed tension springs 18.1 / 2, which are mounted between secondary handguard 17 and primary handguard 19.

In Fig. 8 is a pneumatic Scherenschnittmesserhalter with a double-headed guided actuator on the knife side in a perspective view from the front-top, as he generically in the EP 0 925 159 will be described in detail.

The circular blade is in the rest position and the secondary hand guard in the upper protection position.

On the main body 17 is a part of the actuator can be seen, namely the two guide columns 18.1 / 2 attached thereto Traverse 19. In contrast to the aforementioned embodiment of a one-column knife holder here the cutter head is connected via the traverse 19 with the two guide columns 18. This results in an intermediate space between traverse 19 and primary hand guard 22, in which the secondary hand guard 24 is guided on the primary hand guard 22. Otherwise, the others correspond Components substantially the above and described in detail and namely: depth stop 20 (here, however, without depth adjustment) on the base body 17, cutter head 21, circular blade 23 and angled section 26 with passage slot 25th

In Fig. 9 is the knife holder of Fig. 8 Traverse side shown in perspective view from bottom to back.

The actuator with its traverse and circular blade not visible here is again in the upper rest position and the secondary hand guard in the upper protective position.

Otherwise, the essential other components again correspond to the aforementioned and described in detail: base 17, traverse 18 on the actuator, knife head 19, primary hand guard 20, secondary hand guard 21 with guide slots 22.1 / 2, an upper cam and guide pin 23, lower guide pins 24.1 / 2 and drive spring 25.

In Fig. 10 is the knife holder of Fig. 5 shown in the same view only with the difference that the actuator with circular blade 17 is now in cutting position and the secondary hand guard 18 in lower protective position, the circular blade 17 has passed through its slot 19 through the slot 20.

In Fig. 11 the secondary handguard for clarity as a single part is shown in perspective. Shown are: lower bend 17 with passage slot 18, lower cover 19 for the cutout of the primary hand guard, two side arms 20.1 / 2 with guide slots 21.1 / 2, upper bend 21 for the depth stop, Stützabwinklung 22 for a compression spring.

The functional sequence with kinematics of actuator and secondary hand protection is generally as follows and refers to the sequence of Fig. 5 to Fig. 10 :

As soon as the actuator with the cutterhead and the circular blade mounted thereon moves in the direction of the lower tool, the secondary handguard is simultaneously moved by the drive spring until the fixed stop on the main body is reached. Thus, the secondary handguard has reached its lower protection position. Thereafter, the actuator continues to move until the circular blade has reached its cutting position after passing through the slot of the secondary hand guard. It can easily be seen that the reground smaller diameter circular blade is only slightly above the actuator moved further to come into contact with the lower tool, while the secondary handguard remains in its position.

In the reverse order of cutting in the rest position, the circular blade first returns to the primary protection hood as soon as the actuator moves to the rest position. Only then is the secondary hand guard pushed simultaneously by the upper drive pins on the primary hand guard against the spring force of the drive springs into the upper guard position.

Fig. 12 shows a circular knife holder with a secondary hand guard 37 with a lock. The lock prevents, in a cutting position of the circular blade holder of the secondary hand guard 37 in the lower protective position against an imprinted force, preferably against its drive spring 36, can escape upwards while releasing a knife edge of the circular blade. This allows a fitter to perform, for example, set-up operations without running the risk of unintentionally exposing the circular knife.

Preferably, the barrier is such that the secondary handguard 37 is provided with a barrier that holds it in a lower, in particular in the lowest protective position. For example, the lock is released only via the actuator during its movement from the cutting to the rest position again.

The illustrated in exemplary embodiment pneumatic scissors blade holder can be seen in a front partial view. The actuator with cutter head 31 and mounted thereon circular blade 32 is located in a lower cutting position and a secondary hand guard 37 in a lower protective position. The actuator, which is guided and driven in a base body 30, is not shown in detail, but only by a guide column 35 to which a crosshead 33 of the cutter head 31 is mounted thereon with circular blade and the primary handguard 34. The following are the rigidly fixed in this example on the actuator parts such as guide column 35, cross member 33, cutter head 31 and primary hand guard 34 under the generic term "actuator" summarized. On the base body 30 of the circular knife holder, the drive spring 36 is supported, which presses the secondary hand guard 37 down to a fixed stop 38. On the body is a spring element .39 mounted as a lock with a toward secondary handguard 37 straight bent latch 40 and a return bracket 41. The secondary hand guard 37 has a not visible here retaining slot, in which the catch 40 in a movement of the actuator from the top Rest position is engaged in the lower cutting position by the spring action of the spring element 39. The cross member 33 is provided with a pawl 42, which releases the retaining slot on the return bracket 41 again when the actuator or the cross member 33 moves from its lower cutting in the upper rest position. It can easily be seen that the secondary hand guard 37 can no longer escape upwards in its lower protective position.

Fig. 13 shows the lock Fig. 12 in the form of the spring element 39 in a perspective view. The spring element 39 shows the angled catch 40 and the return bar 41. The pawl 42 is attached to the traverse 33 shown only partially.

Fig. 14 shows in a side view a circular knife holder 43. This has an adjustment 44. In this case, for example, a height adjustment element, in particular an adjusting screw 45 is used, which causes a change in position of a secondary protection 46 via a rotation. For this purpose, the adjusting screw 45 may be coupled directly or indirectly to the secondary protection 46. For example, it is possible to provide a translation in order to enable a particularly fine adjustment and thereby adjustment. The translation may increase or decrease rotation of the adjustment screw 46 in proportion. The adjustment preferably cooperates with a stationary element of the circular knife holder 43. As shown, the adjusting screw 45 acts directly on the secondary protection 45, wherein the adjusting screw 45 is in this representation in an end position. In this a spring 47 is completely compressed. This serves as a force generator element. The force generating element causes the set secondary protection 45 can not be brought out of the adjusted position without overcoming the force applied thereby. Preferably, in an adjustment, the possibility is provided to provide a lock or at least a fuse that prevents the change in the adjustment, unless the lock has been overcome or the fuse has been released. The secondary protection 46 can be, for example, a folded sheet metal, a cast material, for example, made of sheet metal or plastic, or even a solid material that has been processed in accordance with material removal. Preferably, the adjustment is designed such that the circular blade can not be moved from the secondary protection in a rest position of the circular blade even in each maximum position of the adjustment. Furthermore, the secondary protection is advantageously shaped such that in the rest position no lateral access to the cutting area of the circular blade is possible. For this purpose, the secondary region can have a laterally raised web 47.

Fig. 15 shows the circular knife holder 43 Fig. 14 , The height-adjustable adjustment 44 is still in the off Fig. 14 first position. A suspension 48 for the circular blade is moved to a lower position, whereby the circular blade passes into a cutting position. The secondary protection 46 is also moved along its translational guide in a lower position. However, the travel path of the secondary handguard 46 is shorter. As a result, the circular blade can pass through the secondary protection and moved into the cutting position. The secondary protection reaches a stop, which is formed in this embodiment by the adjustment itself. The adjusting screw 45 has a head surface, to which the secondary protection 46 comes to rest. As shown, it can be secondary protection in the region of its guide along the adjustment than in comparison to the diameter of the adjusting screw 45 thinner component, in particular as a sheet metal part formed. However, there is also the possibility that along the guide a sleeve-like geometry is slidably provided about a rail. The secondary hand guard 46 can then be movable on the rail or on the sleeve. By means of this development, a possible tilting risk can be further reduced.

Without changing the basic principle of the invention, further modifications of individual components or groups are possible, such as:

The primary hand guard can also be provided with a straight outlet at the bottom, so that the circular segment-shaped cut undergoes a change in shape, with the secondary hand guard being adapted to it.

The counter-tool facing angled portion of the secondary handguard may be straight, concave or convex, with or without lateral rounding, with or without additional lateral bends to the primary hand guard out.

The guide elements between the primary and secondary handguards can also be reversed by attaching the slots to the primary handguard and the driver and guide pins to the secondary handguard. Likewise, other guide elements are possible, such as e.g. Tongue and groove.

The biased drive springs can be mounted between secondary hand guard and "actuator" and / or body. Likewise, other spring shapes can be used.

Likewise, the described construction is usable when the circular knife holder with razor blades e.g. in a revolver on the cutterhead is equipped.

The design principle can continue to be used in actuators with pneumatic, electric or other types of drive in the same way.

Claims (17)

1. Circular blade holder with a blade head (21) with at least one mounting of a circular blade (5), a hand guard (3),and with an actuator (2) fastened on the blade head (21)with a translational variation of position of the circular blade (5) and of the hand guard (3), which is arranged to be movable relative to the circular blade (5), characterised in that at least one additional translational guide (9.1, 9.2, 10.1, 10.2, 11.1, 11.2) is provided for translational variation of position, along which the hand guard (3) can be automatically guided from a first limit position to a second limit position utilizing an actuating element (14.1, 14.2) arranged separate from the actuator (2), whereby a force can be applied to the hand guard (3) along the translational guide (9.1, 9.2, 10.1, 10.2, 11.1, 11.2) by means of the actuating element (14.1, 14.2), located on the circular blade holder, in the direction of an operating position of the circular blade (5), pressing the hand guard (3) against a stop as limit position, characterised in that a relative movement can be effected between the circular blade (5) and the hand guard (3) by means of the actuator (2), with which the circular blade (5) can be moved out of a shield of the hand guard (3) into its operating position.
2. Circular blade holder in accordance with Claim 1, characterised in that the translational guide (9.1, 9.2, 10.1, 10.2, 11.1, 11.2) has a first guide rail and a second guide rail, which are arranged parallel to one another.
3. Circular blade holder in accordance with Claim 1 or 2, characterised in that the actuating element (14.1, 14.2) is attached as pressure force element with the hand guard (3) and exerts a pressure force directly on the hand guard.
4. Circular blade holder in accordance with one of the preceding claims, characterised in that the actuating element (14.1, 14.2) has a length variation which runs parallel to the translational guide (9.1, 9.2, 10.1, 10.2, 11.1, 11.2).
5. Circular blade holder in accordance with one of the preceding claims, characterised in that the hand guard (3) has at least one coupling position with a component of the circular blade holder, by means of which a limit is placed on a relative movement between hand guard (3) and circular blade holder (5) along the translational guide (9.1, 9.2, 10.1, 10.2, 11.1, 11.2).
6. Circular blade holder in accordance with one of the preceding claims, characterised in that the actuating element (14.1, 14.2) is a spring.
7. Circular blade holder in accordance with one of the preceding claims, characterised in that the hand guard (3) is fully movable relative to the circular blade (5).
8. Circular blade holder in accordance with one of the claims 1-6, characterised in that the hand guard (3) has a primary hand guard (19) and a secondary hand guard (22), whereby the primary hand guard (19) and the secondary hand guard (22) are movable relative to one another along the translational guide (26.1, 26.2, 27.1, 27.2).
9. Circular blade holder in accordance with one of the preceding claims, characterised in that the circular blade holder is arranged in a longitudinal cutting device and the hand guard (3) in a travel position of the circular blade holder for engagement with a material to be cut longitudinally forms an open, vertical gap (a) that is smaller than five millimetres with an opposing component of the longitudinal cutting device.
10. Circular blade holder in accordance with one of the preceding claims, characterised in that a lock is provided in a region of at least one of the limit position that inhibits a relative displacement between hand guard (3) and circular blade (5).
11. Circular blade holder in accordance with one of the preceding claims, characterised in that an adjustment is provided, by means of which a position of the hand guard (3) can be adjusted.
12. Circular blade holder in accordance with one of the preceding claims, characterised in that a safety device is provided which activates when the hand guard (3) butts against an unintended obstacle.
13. Method for protection of a user of a longitudinal cutting device with which at least one circular blade (5) is moved translationally into an operating position for engagement in a longitudinal track and a translational relative movement is executed between a hand guard (3) and a circular blade (5) only at an instant when the hand guard (3) has formed a predeterminable safety gap with an opposing component of the circular blade (5) and the circular blade (5) travels translationally into its operating position.
14. Method in accordance with Claim 13, characterised in that the hand guard (3) is locked when the circular blade (5) travels into the operating position for engagement with a longitudinal track.
15. Method in accordance with Claim 13 or 14, characterised in that the hand guard (3) is constantly subjected to pressure in the direction of the operating position after leaving a rest position.
16. Method in accordance with one of the claims 13-15, characterised in that the hand guard (3) is moved translationally relative to the circular blade (5) during a movement of the circular blade (5) from the operating position into a rest position.
17. Method in accordance with one of the claims 13-16, characterised in that a safety device in activated when a movement of the hand guard (3) impinges on an unintended obstacle.

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