IE902919A1 - Letter punch - Google Patents

Abstract

A paper punch comprises a base part (10) and a pressure lever (18) which is pivotally mounted on lateral pillow blocks on the base part (10) and which acts, against the restoring force of a spring (28), on a hole punch slidingly guided on the base part (10). The pressure lever (18) has two downwardly curved bearing lobes (28) which overlap the outside of the pillow blocks (14), and an apron (30) on the front face of the pressure lever (18) which curves downward in the region between the pillow blocks. Under the action of the restoring force of the spring (20), the apron (30) strikes against impact edges on the pillow blocks (14). To prevent parts of the hand being jammed, the impact edges are arranged on thin-walled extenders (40) of the pillow blocks (14) parallel to the bearing lobes (28), while the lateral edges of the apron (30) have a bend (34) in the vicinity of their lower edges, which together with the adjacent bearing lobe (28), delimits a narrow gap (38) the edges of which open toward the base part and in which the extender (40) engages.

Description

The invention relates to a letter punch with a bottom section, with a pressure lever, which is tittably mounted on lateral mounting frames of the bottom section, acting against the return force of a spring on a punch die, displaceably quieted on Ine hot Loin section, in wtiich respect t tie pressure lever has two laterally downward bent mounting t laps, which external ty overlap the mounting frames, and an apron, which is facesidedly downward bent at the pressure lever in the region between the mounting flaps and abuts under the influence of the return force of the spring against the stop edges on the mounting frames.

With letter punches of this type, the apron is lifted off its stop edge when the pressure lever is depressed. As a rule, an externally accessible gap is thus created, into wtiich, in particular with improper handling of the punch, a linger or part of a hand can be inserted to be caught during the following spring return of the pressure lever, In view ot the large return force required lor the withdrawal of the punch dies from perforated piles of paper, considerable danger ot injury exists, aggravated bv the abutting punch parts often having rather sharp edges.

Based thereon, it is the object of the invention to improve known paper punches ot the earlier described type so that danger of injury is avoioed, even with improper handling of the letter punch.

The inventive solution is based no externally accessible gap operation of the pressure lever, a hand can inadvertently be improper handiing. on the knowledge that must. develop during into which gap part of nserted, even during which are aligned and that the apron To achieve this object., it is suggested according to a first variant of the invention, which is particularly suitable for metal punches, that the stop edges are arranqed on thin-wailed latches, parallel with the mounting flaps, has a bent section on its lateral edges in the vicinity of its bottom edge, which bent section together with the adjacent mounting flaps defines a gap which is open edqed towards the bottom section for the engagement of the latch. The stop edge can hereby be formed either by an upwards orientated step, which abuts against an upper limiting edge of the gap, preferably arranged on the apron, or by a face edge of the latch, which abuts from the rear against the apron in the area near the gap.

According to a second variant of the invention, mainly realised with cast punches, latches with upwards orientated face sides which reach under the apron, are arranged on the mounting frames, the upper edges of said latches forming the abutment surfaces, whilst the apron has rearward extending stops for the upper edges of the latches at a distance from its lower edge. So that no gap, in which a finger could be caught, is created over the entire tilting position between apron and latch whilst operating the pressure Lever, the latches have, at least in their region which is reached over by the apron, a part-cyIindricaL surface curvature, which is coaxial relative to the tilting axis of the pressure lever, and which curvature - 3 ~ releases a constant gap of less than 4 mm over the entire tilt path. A further improvement in this respect is achieved in that the apron is also dish-shaped in its interior surface which faces towards the partcylindrical latch part.

The arrangement of the stops according to the second variant of the invention makes it possible to arrange, in the area between the lower edge of the apron and the stops, a stop slide, which is displaceable between two end positions across the apron and which in the one end position enters into the tilt path and which is arranged as a holding-down means of the pressure lever. In order to avoid unintentional release of the holdtnq-down means during operation of the pressure lever, the stop slide is arrested at least in the end position at the latch as withdrawn from the tilt path, preferably in a detent connection. The stop slide is advantageously guided in a substantially horizontal slot of the apron, comprising an operating head which reaches through the slot to the face side of the punch.

According to a further preferred arrangement of the invention, the distance between the apron and a cross bar, which covers the punch dies at the face side, is chosen to be at least the width of a finger across the entire tilt area of the pressure lever. !t is thus ensured that unintentional catching of parts of a hand is avoided.

Below, the invention is described more in detail, based on two examples of embodiments, schematically illustrated by way of two drawings. Shown are, Ln Fig. 1 : a metal punch in perspective illustration; Fig. 2: a vert of F I g. F i q. 3; a cast Fig. 4: a vert F i g. 3.

The metal punch shown In Figs. 1 and 2 consists substantially of a bottom section 10, a thereto rigidly connected mounting member 12, and a pressure Lever 18, mounted to the mounting frames 14 of mounting member 12 to be tiltable around an axis 16. Furthermore, In the mounting member 12 are guided punch dies 22, each encapsuled by a colled spring 20; when depressing operating lever 18, said dies are displaced downwards against the force of springs 20 whilst passing through Insert slot 24 and template aperture 26 in bottom section 10, With subsequent release, the pressure lever is automatically returned, under the influence of springs 20, to its basic position.

Pressure lever 18 has two laterally downward bent mounting flaps 28, which externally overlap the mounting frames 14, Furthermore, the pressure Lever 18 Is provided with a face-side downward bent stop apron 30, which connects the two mounting flaps 28 with one another. Apron 30 has In the vicinity of its lateral edges and In the region of its bottom edge 32 a rearward orientated flap—like curvature which. together with the adjacent mounting flap 28, defines a gap 38. which is open-edged downwards and closed upwards by a punch edge 36 in the apron. Into said gap enqaqes a thin-walled latch 40 of mounting frame 14, which comprises a step 42, serving as a stop for the cross edge 36, arranged on apron 30. It is in principle also possible that, instead of step 42, an edge - 5 section of latch 42, which reaches under the edge section of the Latch, serves as stop for the pressure Lever. Since the width of gap 38 can be arranged to be smaller than 4 mm, there is no danqer of a finger being caught between the stop edges. It is only important that the bent section 34 is so Long that the Latch 40 engages into gap 38, even whilst pressure Lever 18 is depressed.

The punch-die guides in mounting member 12 are facesidedly covered by a cross bar 43. In ait tilt positions of pressure lever 18, apron 30 and cross bar 43 are at a distance of at Least a finger's width in order to avoid parts of the hand being caught in this area. one piece pr essu re In the cast punch, shown in Figs. 3 and 4, the bottom section 10 and the mounting frames 14 are joined into leaving open the insert slot 24. At the lever 18 are provided again laterally downward bent mounting flaps 28 as well as a downward bent apron 30, which facesidedly connects the mounting flaps to one another. At the mounting frames 14 are arranged facesidedly upwards orientated latches 50 which reach under the apron 30 by way of their upper edge 52, which serves as stop edge. On the inside of apron 30, stop cams 54 protrude at a distance from the bottom edge 32, by which the pressure lever 18, whilst tilting back, abuts under the effect of the spring force against the upper edges 52 of Latches 50 have in their section underneath apron 30 a part-cylindrical curvature, which is coaxial relative to tilt, axis 16, whereas the apron 30 is correspondingly dish-shaped at its side which faces the latches 50. Thus, this gap between apron 30 and latches 50. present during depression of pressure latch 50. The which reaches I ever 18, can be kept at a constant width of l ess t han 4 mm, thus avo iding danger of catchi ng. The desc r i bed arrangement of the stops of the cast punc h as i n F i gs. 3 and 4 i s a I so suitable for accommodat ing an adjustable stop si t de 56 ί n t he area between the apron' s Lower edge 32 and one of the stop cams 54. Such a stop slide 56. displaceably arranged in a horizontal slot 58 of apron 30, serves to hold down pressure Lever 19. which can be engaged, for example during transport and storage, with the adjacent latch upper edge 52. So as not to impede the punch process, the stop slide 56 should be securable, preferably in a hook-type connection, to operating lever 18, at Least in the end position which is removed from the tilt path of the latch. 1

Claims (11)

1. Patent Claims Letter punch with a bottom section, with a pressure Lever, which is tiltably mounted on Lateral mounting frames of the bottom section, acting against the return force of a spring on a punch die, disptaceably guided on the bottom section, in which respect the pressure Lever has two Laterally downward bent mounting flaps, which externally overlap the mounting frames, and an apron, which is facesidedly downward bent at the pressure lever in the region between the mounting flaps and abuts under the influence of the return force of the spring against the stop edges on the mounting frames, characterised in that the stop edges are arranged on thin-walled latches (40) of the mounting frames (14), which are aligned parallel with the mounting flaps <28), and that the apron (30) has a bent section (34) on its lateral edges in the vicinity of its bottom edge (32), which bent section together with the adjacent mounting flaps (28) defines a gap (38) which is open edged towards the bottom section (10) for the engagement of the latch (40). character i sed by an upwards which abuts against an <36> of the gap (38),

2. : Letter punch according to claim 1, in that the stop edge is formed orientated step (42), upper limiting edge preferably arranged on the apron.

3. : Letter punch with a bottom section, with a pressure lever, which is tittabty mounted on Lateral mounting frames of the bottom section, acting against the return force of a spring on a punch die, displaceably guided on the bottom section, in which respect the pressure lever has Laterally downward bent mounting flaps, which externatly overlap the mounting frames, and an apron, which is facesidedly downward bent at the pressure lever in the region between the mounting flaps and abuts under the influence of the return force of the spring against the stop edges on the mounting frames, character Ised in that latches (50) with upwards orientated face sides, which reach under the apron (5®), are arranged on the mounting frames ¢14), the upper edges ¢52) of said latches forming the abutment surfaces, and that the apron ¢30) has rearward extending stops ¢54) for the upper edges ¢52) of

4. ; the latches edge (32). ¢50) at a distance from its Lower Letter punch according to claim 3, characterised in that the I at ches (50) have, at Least in their regt on wh i c h is reached over by the apron <30), a part-cylindrical surf ace

5. : curvature, which is coaxial relative to the tilting axis ¢16) of the pressure Lever (18). Letter punch according to claim 4, characterised in that the apron (30) Is dish-shaped in its interior surface which faces towards the partcylindrical latch part (50) Letter punch according to one of the claims 3 to 5. characterised in that in the area between the lower edge of the apron (32) and the stops ¢54),

6. ; - 9 is arranqed a stop slide <56), which is displaceable across between two end positions and which in the one end position enters into the tilt path of one of the latch upper edges (52) and which is arranged as a holding-down means of the pressure lever (18)

7. : Letter punch according to claim 6, characterised in that the stop slide (56) is arrested at (east in the end position at the latch (52) as withdrawn from the ti Lt path, preferably in a detent connection.

8. :

9. : Letter punch according to claim 6 or 7, characterised in that the stop slide (56) is guided in a substantially horizontal siot <58) of the apron (30) of pressure lever (18). Letter punch according to claim 8, characterised in that the stop slide (56) comprises an operating head which reaches through the slot (58).

10. : Letter punch according to one of the claims 1 to 9, characterised in that the distance between the apron (30) and a cross bar (43), which covers the punch dies at the face side, is at least the width of a finger across the entire tilt area of the pressure lever(l8>.

11. A letter punch substantially as hereinbefore described with reference to the accompanying drawings. Dated this the 13th day of August, 1990o