WO2000062984A1

WO2000062984A1 - Vibrating means for punching devices

Info

Publication number: WO2000062984A1
Application number: PCT/GB2000/001496
Authority: WO
Inventors: Paul Arthur Aries; David Mead
Original assignee: Acco-Rexel Group Services Limited
Priority date: 1999-04-17
Filing date: 2000-04-17
Publication date: 2000-10-26
Also published as: GB2351934B; GB9908693D0; GB0028279D0; AU4130400A; GB2351934A

Abstract

A punching device comprising a punching assembly comprising a plurality of individual punch members (8) carried on a mounting plate (6), for movement through apertures in a guide plate (10), through a punching slot (12) into which a stack of material to be punched may be fed, and into guide apertures (14) in a base plate (15). The punches are moved from their advanced positions by the application of force to an operating member (16), conveniently by the use of force transmitting members (18). Interposed between the force transmitting means and the punches is a vibrating means (18) to apply vibrations to each punch member during movement of the punching assembly from its retracted to its advanced position. The vibration means may be mechanical, electrical, or at ultrasonic frequency.

Description

VIBRATING MEANS FOR PUNCHING DEVICES

Description of Invention

This invention is concerned with improvements relating to punching devices, in particular devices for the punching of a plurality of holes in a stack of sheets, such as of paper. Such devices are hereinafter referred to as being of the kind specified.

A conventional punching device of the kind specified comprises a housing defining an opening or slot into which one or more sheets of paper or the like material (hereinafter referred to as paper, for convenience) may be located preparatory to a punching operation, said opening or slot hereinafter being referred to as the punching slot.

The slot is conventionally bounded by a guide plate and a base plate, each being provided with a plurality of aligned apertures. Mounted on the housing is a punching assembly comprising a plurality of punch members guided for rectilinear movement between retracted and advanced positions.

Operating means is provided, which may be manual or power-operated (eg. by an electric motor) to move the punch members from their retracted to their advanced positions, causing them to pass though the apertures in the guide plate, across the punching slot and through the sheets of paper therein, and into the apertures in the base plate.

The punch members may form part of a punch plate which is mounted for rectilinear sliding movement, and a conventional operating means comprises a plurality of pinions, rotatable by handle means, said pinions being engagable with rack formations on the punching plates, operation of the handle means causing rotation of the pinions to move the punch plate between its advanced and retracted positions.

Such a device is described in the specification of our UK patent number 2293129. Alternatively the punch plate may be moved by a linearly moveable operating member.

An alternative machine comprises a plurality of separate punch members slideable in guide means, and an operating member engageable with said plurality of punch members and which is moveable either by power means or by manually operable means to move the punch members from their retracted to their advanced positions. Conveniently in such a machine spring means may be utilised to urge the punch members from their advanced positions into engagement with the operating member.

A problem encountered with conventional punching devices of the kind specified is the force required to cause the punch members to pass through a stack of sheets located in the punching slot, particularly when it is desired to punch the maximum number of holes, conventionally 21. Not only is it desirable for operating purposes to reduce the force required as much as possible, but also the machine must be designed to withstand the maximum forces to which it will in use be subject, and thus reducing the forces required may result in a small machine, lighter in weight and easier to operate.

Suggestions have been made, such as in the specification of our UK patent application number 2293128, to reduce the force required by utilising specially designed cutting edges on the punch members, but despite the major obvious advantages of being able to reduce the force required to operate a punching device of the kind specified, no significant improvement has been made over very many years.

According to this invention there is provided a punching device of the kind specified, comprising means to cause the punch members to vibrate as they move through the punching slot.

In this manner it has been found that the force required to cause the punch members to pass through the sheets of paper in the punching slot may be reduced significantly, by 50% or more. This means that the robustness of the machine as a whole, particularly the punching mechanism thereof, may significantly be reduced, and/or the machine designed to punch holes in a larger number of sheets of paper.

According to this invention there is also provided a punching device comprising:

(a) a housing defining a punching slot into which an edge margin of one or more sheets of paper, or the like material, may be located;

(b) a punching assembly comprising a plurality of punch members mounted on the housing for rectilinear movement from a retracted position to an advanced position to punch holes in paper located within the punching slot;

(c) operating means to cause the punching assembly to move from its retracted to its advanced position; and

(d) vibrating means to apply vibrations to each punch member during movement of the punching assembly from its retracted to its advanced position.

Desirably, the vibration means is operative to cause punch members to vibrate at a frequency of at least lOHz, desirably in the range 10 to 50 KHz or more.

The vibrations applied to the punch members is desirably primarily longitudinal, but desirably the construction and arrangement is such that some movement of the cutting edges of the punch members in a direction at right angles to the longitudinal axis is caused by the vibration means.

The vibration means may be in the form of mechanical means, for example, rotary cam means operating on the punch members, or may be electronically induced, such as by the use of a solenoid acting on the punch members. Conveniently such vibration means operate in the range l OHz to lKHz, preferably 100Hz to 500Hz.

Desirably however ultrasonic vibration means is utilised, to cause the cutting tips of the punch members to vibrate at ultrasonic frequency, such as by the use of piezo-electric elements. Conveniently such vibration means operate in the range 15KHz to 40KHz, preferably at about 20KHz.

The vibration means may comprise a vibration device associated with each punch member, for example being inteφosed between the operating means and each punch member.

Alternatively the vibration means may comprise one or more vibration devices acting jointly on all the punch members, for example, being inteφosed between the operating means and a force-transmitting member engageable with all punches.

There will now be given detailed descriptions, to be read with reference to the accompanying drawings, of various punching devices which have been selected for the puφoses of illustrating the invention by way of example.

The accompanying drawings are schematic views illustrating various ways in which the present invention may be put into practice. For details of the construction and operation of parts of the machine not described herein, reference should be made to the prior art, for example, to the specifications of our UK patents referred to above.

Thus Figure 1 shows schematically a punching assembly comprising a plurality of individual punch members 8a carried by a mounting plate 6a, for movement through apertures in a guide plate lOa_^ through a punching slot 12a, into which a stack of material to be punched may be fed, the punches moving into advanced positions in which they are located in guide apertures 14a in the base plate 15a.

The punches are moved to their advanced positions by the application of force to an operating member 16a, through force transmitting members 18a, which comprise upper and lower force transmitting portions 20a, 22a respectively, with a cam face 24a therebetween. One of the force transmitting portions is mounted for rotational movement, about the longitudinal axis by drive means (not shown). During normal operation of the punching machine, a downward force is applied to the operating member, and carries the punches into engagement with a stack of material in the punching aperture 12a. By rotation of the rotary portions of the force transmitting members 18a, a vibratory force is produced in the range 50 - 100Hz which renders the passage of the punches 8a through the stack of paper and into the guide apertures 14a easier to effect, and in particular capable of being effected with a lower applied force.

Whilst in the embodiment shown in Figure 1 the vibration means, (afforded by the force transmitting portions 20a and 22a, together with the capability of one of these to be rotated), acts on the mounting plate 6a to be applied to all punches, in the embodiment illustrated in Figure 2, in which similar numerals with the suffix b have been utilised, a separate vibration means is associated with each punch member.

Whilst the embodiments illustrated in Figure 1 and 2 illustrate the use of a mechanical vibration means, in Figure 3, in which similar numerals with the suffix c have been utilised, electrical vibration means is utilised, the force transmitting members 18a of Figure 1 being substituted by solenoids 18c, which may be operated at high frequency, conveniently in the range 100Hz to lKHz, to produce, in addition to the transfer of downward force from the operating member 16c to the mounting plate 6c of the normal operating force, a hammer-like action dependant upon the frequency of energisation and relax of the solenoids 18c.

The embodiment illustrated in Figure 4, in which similar numerals with the suffix d have been utilised, shows the substitution of individual solenoids 18d for the individual force transmitting members 18c of the construction shown in Figure 2.

In the construction shown in Figure 5, in which similar numerals with the suffix e are utilised, the vibration means is afforded by force transmitting members 18e comprising brackets 20e which cany eccentrically-mounted rollers 24e. Whilst the force transmitting members may as previously described be utilised to transmit operating force from the operating member 16e to the mounting plate 6e, a vibrational force may be applied to the mounting plate 6e by rotation of the rollers 14e and hence to the individual punch members 8e, to assist their passage through a stack of material located within the punching aperture 12e. Conveniently a frequency in the range 100 - 200Hz is used.

Similarly, in the embodiment illustrated in Figure 6, in which similar numerals with the suffix f are utilised, individual vibration means comprising a bracket 18f and an eccentrically-mounted wheel 24f are utilised for individual punch members 8f.

In the embodiment illustrated in Figure 7, in which similar numerals with the suffix g have been utilised, the vibration means is provided by piezoelectric vibration means, operative between the operating member 16g and the mounting plate 6g, simultaneously to transmit load from the operating member 16g to the punches 8g. The piezo-electric devices 18g are operated at ultrasonic frequency, to cause a longitudinal vibration to be applied to the individual punch members 8g to assist their passage through the material being punched.

In the embodiment illustrated in Figure 7 in which similar numerals with the suffix h have been utilised, a piezo-electric device has been utilised in association with each punch member 8h, said pizo-electric devices 18h similarly being vibrated at high frequency, conveniently in the range 15KHz to 40KHz, to cause a longitudinal vibration to be applied to the punch members.

In accordance with ultrasonic technology, the lower face of the piezoelectric device contacting the punch member preferably forms an antinode, and advantageously the length of the individual punch members is nλ÷2, where λ is the wavelength of vibration, ensuring that the cutting tips of the punch members similarly provide antinodes. Figure 9 illustrates the utilisation of the invention in relation to a conventional punching device in the form of a punching plate 9j, having integral punch members 8j in staggered relationship. Unlike the specification of our above referred to UK patent 2293129, the rack plate 16] is separated from the punch plate 9χ, a pinion 30 being provided which is engageable with rack formations 32, to move the rack plate, and through the force transmitting members 18j, to move the punch plate 9j.

As with the embodiment illustrated in Figure 7, the force transmitting members 18j are afforded by piezo-electric devices which, simultaneously with transmission of force from the rack plate 16j to punch plate 9], may also apply to the punch plate primarily longitudinal vibrations at a frequency of about 20KHz.

In addition, a desired length of punch member is used which ensures, as far as possible, that the tips lie in regions of the punches which are anti-nodes. In this regard, it will be appreciate that, whilst the degree of stagger of the punches shown in Figure 9 has been exaggerated for the puφoses of clarity, necessarily with a staggered formation some only of the punches will be anti- nodes.

Notwithstanding, it has been found that such vibration produced at the tip of the punches, whilst not being maximal, nonetheless improves the movement of the punches through the paper.

In the particular construction of punch members 8] illustrated in Figure 9, whilst most of the vibrational energy emanates from the punch members 8j in the longitudinal direction, with the particular construction of cutting edge illustrated in Figure 9, some of the vibrational energy emanates from the cutting edges in a direction at right angles to the longitudinal axis, further assisting passage of the punches through a stack of paper in the punching slot.

In the present specification "comprise" means "includes or consists of and "comprising" means "including or consisting of. The features disclosed in the foregoing description, or the following claims, or the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, as appropriate, may, separately, or in any combination of such features, be utilised for realising the invention in diverse forms thereof.

Claims

1 A punching device of the kind specified comprising means (18) to cause the punch members (8) to vibrate as they move through the punching slot (12).

2 A punching device comprising:

(a) a housing defining a punching slot into which an edge margin of one or more sheets of paper, may be located;

(b) a punching assembly comprising a plurality of punch members (18) mounted on the housing for rectilinear movement from a retracted position to an advanced position to punch holes in paper located within the punching slot;

(c) operating means (16, 30, 32) to cause the punching assembly to move from its retracted to its advanced position; and

(d) vibrating means (18) to apply vibrations to each punch member (8) during movement of the punching assembly from its retracted to its advanced position.

3 A punching device according to one of claims 1 and 2 wherein the vibration means is operative to cause the punch members to vibrate at a frequency of at least l OHz, desirably in the range 10 to 50 KHz or more.

4 A punching device according to any one of the preceding claims wherein the vibrations applied to the punch members is primarily longitudinal.

5 A punching device according to any one of the preceding claims wherein the construction and arrangement is such that some movement of the cutting edges of the punch members in a direction at right angles to the longitudinal axis is caused by the vibration means. 6 A punching device according to any one of the preceding claims wherein the vibrations means is in the form of mechanical means (20a, 22a, 24a; 20b, 22b, 24b; 20e, 24e,; 20f, 24f).

7 A punching device according to any of claims 1 to 5 wherein the vibration means (18c, 18d, 18j) is electronically induced.

8 A vibrating device according to any one of claims 1 to 5 wherein the vibration means is operative to cause the cutting tips of the punch members (8) to vibrate at ultrasonic frequency.

9 A vibration device according to any one of the preceding claims wherein the vibration means comprises a vibration device associated with each punch member.

10 A punching device according to any one of claims 1 to 8 wherein the vibration means comprises one or more vibration devices acting jointly on all the punch members.