GB2260289A

GB2260289A - An electrically-powered stapling machine

Info

Publication number: GB2260289A
Application number: GB9119327A
Authority: GB
Inventors: Mark Owens; John Drane
Original assignee: Ofrex Group Holdings PLC
Current assignee: Ofrex Group Holdings PLC
Priority date: 1991-09-10
Filing date: 1991-09-10
Publication date: 1993-04-14
Anticipated expiration: 2011-09-10
Also published as: GB2260289B; GB9119327D0

Abstract

A stapling machine comprises a staple driver 12 biased towards a staple-ejection slot 6 of a staple magazine 5, an electrically-driven cam element 21 provided with rising cam surfaces 25, 26 and vertical drops 27, (28) and a rod 13 connected to driver 12 and riding on cam surfaces 25, 26. Rotation of element 21 by electric drive causes rod 13 to ride up and along cam surfaces 25, 26 to raise the driver 12 against the bias of springs 17, 18 until the rod 13 drops suddenly at vertical drops 27, 28 whereupon driver 12 is propelled by springs 17, 18 to enter ejection slot 6 to drive staples through a stack of papers received in a recess 3 between a base 1 having anvil 4 and the rest of the machine. Element 21 has switch actuating projections to disable electric after predetermined rotation. Presence of paper is sensed to actuate electric drive. Presence or absence of a staple in slot 6 may be sensed and absence of a staple inhibits drive. <IMAGE>

Description

DESCRIPTION OF INVENTION "Improvements in or relating to an electrically-powered stapling machine THE PRESENT INVENTION relates to an electrically-powered stapling machine.

It has been proposed previously to provide an electrically-powered stapling machine, but previous attempts have not proved to be satisfactory.

The present invention seeks to provide a satisfactory electrically-powered stapling machine.

According to this invention there is provided a stapling machine, said stapling machine comprising a guide to guide staples, a staple-ejection slot provided at one end of the guide, means to bias staples within the guide towards the staple-ejection slot, a staple-ejector blade movable to drive a staple through the staple-ejection slot, an anvil located adjacent the staple ejection slot adapted to deflect the ends of the arms of a staple driven through the staple-eject on slot, resilient means to bias the staple-ejection blade toward the staple-ejecting position, there being a cam element and electrically-powered means to drive the cam element, the cam element being adapted, on operation thereof, to engage the staple-ejection blade or means associated therewith, firstly to move the staple-eject ing blade against the bias applied thereto, and then to release the staple-ejecting blade to permit the staple-ejecting blade to move to the staple-ejecting position under the bias applied thereto.

Preferably the staple-ejecting blade is provided with a rod or bar which extends substantially transversely of the axis of the staple magazine, the said biassing means comprsing springs engaging the ends of the rod or bar.

Conveniently the springs comprise helical tension springs.

Advantageously the cam element comprises an annular cam element surrounding the staple-ejecting blade, the cam element presenting two cam portions, each end of the transverse rod or bar engaging one of said cam portions.

Preferably the cam portions are defined by an upstanding peripheral wall provided on the annular cam element.

Conveniently each cam portion comprises a relatively low region located at the base of an upwardly extending inclined region which then terminates in a substantially vertical drop to the relatively low region of the next cam portion.

Preferably the cam element is provided with peripheral gear teeth engageable directly or indirectly by an electric motor.

Advantageously a switch is provided adapted to disable the electrically-powered means which drive the cam element, the switch being adapted to be activated whenever the cam element reaches a predetermined position.

Preferably a protrusion or the like is provided on the cam element which is engaged by a micro-switch when the cam element reaches the predetermined position.

Conveniently means are provided to respond to the insertion of paper into a slot between the staple-ejection slot and, said means being adapted to initiate operation of the machine.

Preferably means comprise a micro-switch or the like contacted by paper inserted into the slot.

Conveniently means are provided adapted to respond to the presence or absence of a staple in the ejectIon slot, said means being adapted to inhibit the electrically-powered means when there is no staple present in the ejection slot.

Preferably said means responsive to the presence or absence of a staple in the staple-ejection slot provide a visible indication when no staple is present in the staple-ejection slot.

In order that the invention may be more readily understood, and so that further features thereof may be appreciated, the invention will now be described, by way of example, with reference to the accompanying drawings in which FIGURE 1 is a perspective view of the operative part of a stapling machine in accordance with the invention with parts thereof cut away for the sake of clarity of illustration, FIGURE 2 is a front view of the operative part of the stapling machine of Figure 1, again with parts cut away for the sake of clarity of illustration, FIGURE 3 is a side view of the part of the stapling machine as illustrated in Figures 1 and 2, FIGURE 4 is a side view corresponding to Figure 3 but with part cut away to illustrate the staples in the staple guide, and FIGURE 5 is a top plan view of the operative part of the stapling machine as illustrated in Figures 1 to 4.

It is to be appreciated that the operative parts of the stapling machine, as are now to be described will, in use, be provided with a cover. However, the detail of the cover does not form any significant part of the present invention.

A stapling machine in accordance with the invention comprises a base which supports a superstructure 2, the superstructure 2 containing and supporting the operative parts of the stapling machine, as will be described.

Adjacent one end of the base the superstructure 2, together with the base 1, defines a slot 3 adapted to receive a stack of papers to be stapled together.

The base 1 supports, in the region of the slot, an anvil 4, the anvil comprising a plate of metal having formed in the upper surface thereof two recesses adapted to receive the ends of the staple and deflect the staple inwards, as the staple is driven downwardly, as is con ventional in a stapling machine. The anvil may be a reversible anvil having two sets of recesses formed in it, the anvil being reversible so that a first set of recesses adapted to clinch the ends of the staple inwardly may be aligned with the staple or so that a pair of recesses adapted to deflect the ends of the staple outwardly may be aligned with the staple.

A staple guide 5 Is provided within the housing, the staple guide terminating with a staple-ejection slot 6 located immediately above the slot defined between the housing and the base, so that the staple-ejection slot is aligned with the pair of recesses provided in the anvil.

The staple guide 5 is adapted to receive a strip of staples, and contains a spring-biassing means 8 and an associated pusher 9 adapted to push the strip of staples towards the staple-ejection slot.

Mounted towards the rear of the slot 3 adapted to receive the stack of papers to be stapled are two micro-sitches 10,11 which is activated when a stack of papers is inserted into the slot. Operation of these m.cro-sw.tches actuates the stapling cycling, as will be described hereInafter.

A staple-ejector blade 12 is provided which is movable vertically, the staple-ejector blade being aligned with the staple-ejection slot 6. Movement of the staple-ejector blade in a downward sense will cause the staple-ejector blade 12 to contact a staple, from the staple strip 7 and drive that staple downwardly, through the staple-ejection slot, so that the two arms of the staple pass through a stack of paper present in the slot between the superstructure and the base, the ends of the staple then being deflected by the anvil.

The staple-ejector blade 12 is connected, at its upper end, to a rod or bar 13 which extends transversely of the base. Each end of the rod or base is guided in a elongate vertical guide slot 15,16. A respective tension spring 17,18, of helical form, is connected to each end of the bar, the other end of each spring being connected to a respective anchoring point 19,20 adjacent the base 1. The bar 13, and the staple-ejector blade, can thus move upwardly against the spring-bias provided by the two springs and equally can move downwardly under the bias provided by the springs.

A rotatable cam element 21 is provided which is located under the transverse rod or bar. The cam element 21 is of annular form, and surrounds the axis of the staple-ejection blade 12. The cam element comprises a horizontal base having a toothed outer periphery 22 and a central aperture 23, through which the staple-ejector blade passes, the base carrying a peripheral upstanding side wall 24 which is circular in plan. The side wall, however, defines two cam ramps 25,26, each extending from a low point to a high point. Each cam ramp terminates with a substantially vertical drop 27,28 between the high point and the low point of the next ramp. The two ramps are symmetrically located about the annular cam element and the transverse rod or bar extends across the cams so that the bar touches each cam at a corresponding point.

A housing 30 mounted on the superstructure contains a motor and a drive mechanism to engage the toothed outer periphery 22 of the cam element 21 to cause the cam element to rotate in a clock-wise sense as viewed from above in Figure 5. It will be appreciated that as the cam element 21 rotates the transverse rod or bar 13 will pass through a position at which the bar is at the low point of each cam ramp 25,26, and, as the element 21 rotates, will be driven up each cam ramp 25,26, thus causing the staple-ejector blade 12 to move upwardly against the spring-bias applied thereto by the two tension springs 17,18.When the transverse rod or bar 13 reaches the high point of the two cam ramps 25,26, the next slight rotational movement of the cam element 21 will cause the transverse rod or bar 13 to become aligned with the two vertical portions 27,28 extending between the high point of one cam ramp and a low point of the next cam ramp, thus enabling the transverse rod or bar 13 to move downwardly under the spring-bias applied thereto by the tension springs 17,18, consequently causing the staple-ejector blade 13 to move downwardly relatively switfly, to drive a staple through the staple ejection slot 6.

Two protrusions 29,30 are provided on the exterior surface of the cam element, these protrusions being positioned to be contacted by the arm 31 of the micro-switch, the switch being turned to the "off" pos iton when the arm 31 is in contact with one or other of the protrusions.

At the rear of the stapler, means are provIded to obtain access to the staple guide in order to replenish the supply of staples therein.

The motor that drives the cam element may be powered by batteries, which would be contained within a suitable receptacle within the housing, and the batteries may be of the rechargeable type. Alternatively, the stapler may be adapted to be powered by mains electricity.

In use of the stapling machine, as described, the stapling machine will initially be in a condition where one of the projections 30 on the cam element 21 will be in contact with the arm 31 of the micro-switch 32, which is connected to disable the motor which drives the cam element 21. Thus the cam element 21 is stationary. At this point in time, the transverse rod or bar 13 is at an intermediate position on the two cam ramps 25,26. The staple-ejector blade 12 is thus elevated above the staple guide 5. A stack of paper to be stapled may then be inserted into the slot 3 between the superstructure 2 and the base 1. The edge of the stack of paper will contact the micro-switches 10,11 provided within the slot, these micro-switches being connected to activate the motor.

When the motor is activated the cam element 21 begins to rotate. This moves the transverse bar 13 further upwardly against the bias applied by the tension springs 17,18, and also moves the protrusion, on the cam element, away from the arm 31 of the respective micro-switch 32. Thus this micro-switch no longer "dis- ables" the motor. The motor thus continues to rotate until the transverse bar 13 passes the high point on the two cam ramps 25,26, when the transverse bar 13 moves swirftly downwardly to the low point on the two cam ramps, under the bias applied by the tension springs 17,18, thus moving the ejection blade downwardly. The staple is thus driven downwardly to staple the sheets of paper together.The cam element 21 continues rotating, thus moving the staple-ejection blade upwardly against the bias applied thereto by the tension springs, until the next projection 29 contacts the arm 31 of the respective micro-switch 32, thus dis-enabling the motor. The cam element 21 then stops rotating, and the device is ready to repeat the described cycle of operation.

While the invention has been described with reference to one embodiment it is to be appreciated that modifications may be effected without departing from the scope of the invention.

Whilst in the described embodiment operation of the device is initiated by micro-switches located within the slot between the base and the rest of the superstructure, operation may be actuated by an optical arrangement adapted to sense the presence of paper within the slot, such as a co-operating light-emitting diode and photo-sensitive transistor located in alignment on opposite sides of the slot, or operation of the device may be actuated by a manually operable switch provided at a convenient location on a housing covering the superstructure, for example, on the top of the housing immediately above the slot between the housing and the base.

Means may be provided to sense the presence of a staple in the staple-ejection slot and, of course, to sense the absence of a staple within the staple-ejection slot. Such an arrangement may comprise an optical device comprisIng a light-emitting diode and a photo-sensitive transistor located on opposite sides of the staple guide in the region of the staple-ejection slot, so that if a staple is present in the staple-ejection slot it will prevent light from the light-emitting diode passing to the photo-sensitive transistor. The arrangement which senses the presence of a staple in the staple-ejection slot may be associated with means to inhabit operation of the motor when no staple is present in the slot and may also be associated with means to provide a visible indication that there is no staple in the staple-ejection slot, for example, a light-emitting diode visible from the exterior of the housing. Such a diode would provide an indication to the user of the device that it is necessary to insert further staples into the stapling machine.

Whilst the invention has been described with reference to an embodiment in which the rotary position of the cam element is sensed by means of projections provided on the cam element and an associated micro-switch, in a modified embodiment of the invention, the position of the cam element may be detected by optical means. Thus, for example, a light-emitting diode and a photo-sensitive transducer may be located on opposite sides of the cam element, and apertures may be formed extending through the cam element, the apertures being co-aligned with the light-emitting diode and the light-sensitive transducer, thus permitting light from the diode to fall on the photo-sensitive transducer when the cam element is in an appropriate predetermined position.

Whilst reference has been made above to the presence of helical tension springs to bias the staple-ejector blade downwardly, other resilient means may be used for this purpose, such as appropriately designed leaf-springs.

Claims

CLAIMS:

1. A stapling machine, said stapling machine comprising a guide to guide staples, a staple-ejection slot provided at one end of the guide, means to bias staples within the guide towards the staple-ejection slot, a staple-ejector blade movable to drive a staple through the staple-ejection slot, an anvil located adjacent the staple ejection slot adapted to deflect the ends of the arms of a staple driven through the staple-ejection slot, resilient means to bias the staple-ejection blade toward the staple-ejecting position, there being a cam element and electrically-powered means to drive the cam element, the cam element being adapted, on operation thereof, to engage the staple-ejection blade or means associated therewith, firstly to move the staple-ejecting blade against the bias applied thereto, and then to release the staple-ejecting blade to permit the staple-ejecting blade to move to the staple-ejecting position under the bias applied thereto.

2. A stapling machine according to Clam 1 wherein the staple-ejecting blade is provided with a rod or bar which extends substantially transversely of the axis of the staple magazine, the said biassing means comprsing springs engaging the ends of the rod or bar.

3. A stapling machine according to Claim 2 wherein the springs comprise helical tension springs.

4. A stapling machine according to Claim 2 or 3 wherein the cam element comprises an annular cam element surrounding the staple-ejecting blade, the cam element presenting two cam portions, each end of the transverse rod or bar engaging one of said cam portions.

5. A stapling machine according to Claim 4 wherein the cam portions are defined by an upstanding peripheral wall provided on the annular cam element.

6. A stapling machine according to Claim 4 or 5 wherein each cam portion comprises a relatively low region located at the base of an upwardly extending inclined region which then terminates in a substantially vertical drop to the relatively low region of the next cam portion.

7. A stapling machine according to any one of Claims 4 to 6 wherein the cam element is provided with peripheral gear teeth engageable directly or indirectly by an electric motor.

8. A stapling machine according to any one of Claims 1 to 7 wherein a switch is provided adapted to disable the electrically-powered means which drive the cam element, the switch being adapted to be activated whenever the cam element reaches a predetermined pos ition.

9. A stapling machine according to Claim 7 wherein a protrusion or the like is provided on the cam element which is engaged by a micro-switch when the cam element reaches the predetermined position.

10. A stapling machine according to any one of the preceding Claims wherein means are provided to respond to the insertion of paper into a slot between the staple-ejectlon slot and, said means being adapted to initiate operation of the machine.

11. A stapling machine according to Claim 10 wherein said means comprise a micro-switch or the like contacted by paper inserted into the slot.

12. A stapling machine according to any one of the preceding Claims wherein means are provided adapted to respond to the presence or absence of a staple in the ejection slot, said means being adapted to inhibit the electrically-powered means when there is no staple present in the ejection slot.

13. A stapling machine according to Claim 12 wherein said means responsive to the presence or absence of a staple in the staple-ejection slot provide a visible indication when no staple is present In the staple-ejection slot.

14. A stapling machine substantially as herein described with reference to and as shown in the accompanying drawings.

15. Any novel feature or combination of features disclosed herein.