GB2193459A - Pocket knife - Google Patents

Description

1 GB2193459A 1 SPECIFICATION is supported almost at its centre by means of

a shaft 8 which is mounted in the rear section Pocket knife bridging the space between the side plates 1, 1 and may be formed separately from the The present invention relates to an improved 70 lever 3, as shown in the drawing, or may be pocket knife. integral therewith. A projection 7 on the end Conventionally, a pocket knife in which the section of the swinging bar 3, mates with a knife blade can be folded into the space be- recess 6 at the base 5 of the knife blade 2, tween a pair of side plates forming the handle to secure the knife blade 2 in the fully open has a pivoted lever for locking the knife blade 75 position. The interlocking projection 7 and re in the open state. An end section of the pi- cess 6 are not however, essential, since the voted [ever is pressed against the base por[ever 3 is biased toward the interlocking posi tion of the knife blade by the application of a tion of the projection 7 and recess 6 by a leaf turning moment centered around the pivot, spring 4 and the biasing force alone may be and the knife blade is secured in place by the 80 made sufficient to hold the blade 2 in the fully resilience of a spring member acting on the open position.

lever. In particular, the lever is pivoted on a The shaft 8 is supported in bearing re shaft inserted in opposed holes bored through cesses 9 which are formed in the inner sur both side plates. face of the side plates 1, 1. These recesses 9 In this arrangement, both ends of the shaft 85 do not penetrate to the outer surface of the are exposed at the outside surface of the side side plates 1,1, but are so-called "blindholes".

plates, so that it is necessary to grind this Each bearing recess 9 communicates with a region to ensure that the ends of the shaft are guide channel 10 formed in the inner surface flush with the outer surfaces of the side of its side plate to extend radially from the plates. However, the shaft is mounted in an 90 recess 9 to the edge of the side plate 1. As upper part of the side plate, wherein the outer shown in Figure 2, the mount 15 of each surface is finished as a curved surface for guide channel 10 opens into a notch 14 in the ease in boring, so that the grinding operation top edge of the side plate 1, which notch 14 requires experience and considerable time. is provided to enable a user to depress the This is the bottleneck in the mass production 95 rear end of the lever 3 to release the inter of pocket knives. locking projection 8 and recess 6 when fold One object of the present invention is to ing the blade. The mount 15 of the channel avoid the disadvantages and drawbacks inher- 10 may, however, open at another peripheral ent in conventional pocket knives. surface.

According to the present invention, we pro- 100 The turning moment biasing the lever 3 is pose a pocket knife having a knife blade that applied about the pivot i.e. the shaft 8, by the is foldable between a closed position wherein leaf spring 4 which is mounted between the the blade is disposed within a cavity in the side plates 1, 1, to engage a step or notch to blade, and an open position, the blade being the rear of the shaft 8. This additionally held in the open position by a lever biased 105 serves to hold the shaft 8 in the bearing re against a base portion of the knife blade and cesses 9 preventing its withdrawal along the pivoted by means received in recesses in the guide channel 10. One end of the leaf spring opposed side surfaces of the cavity, each side 4 is held in a hole 13 in a spacer 12 mounted surface having therein a guide channel extend- between the side plates 1, 1.The flexible leaf' ing from the recess to an opening at a periph- 110 4 and the spacer 12 may be separate as eral edge of the handle. shown, or integrally formed.

A preferred embodiment of the invention During assembly, all components other than will now be described by way of example the swinging bar 3 and the swing shaft 8 are with reference to the accompanying drawings mounted in advance in the space between the in which: 115 side plates 1, 1 (i.e. the knife blade 2 is __ Figure 1 is a longitudinal cross-section of a mounted in a freely rotatable manner in the pocket knife according to the present inven- space between the side plates 1,1 and the tion; spacer 12, is interposed and secured there Figure 2 is an elevation of the inner surface between). One end of the leaf spring 4 is of a side plate of the knife of Figure 1; 120 inserted into the hole 13 provided in the spa Figure 3 is a lateral cross-section taken in cer 12 and the shaft 8 is then attached to the the vicinity of the swing shaft in Figure 1; and lever bar 3, inserted into the channel mouth Figure 4 is a lateral cross-section of the side 15, and pushed along the guide channel 10 to plate of Figure 2 taken in the vicinity of the the point where the ends of shaft 8 are sup- bearing section. 125 ported in the bearing recesses 8. At this The pocket knife shown in the Figures has a stage, the knife blade 2 is set in the fully knife blade 2 mounted in a freely rotatable open position with the end of the lever 3 in manner so that it can be folded into the space contact with the upper edge of the base por between a pair of side plates 1, 1. A pivotal tion 5 of the knife blade 2. In addition, the lever 2 in the form of an elongate metal leaf 130leaf spring 4 contacts the lower edge of the 2 GB2193459A 2 lever 3, and presses it in the upward direc tion.

Accordingly, the shaft 8 which pivotally mounts the lever 3 is not exposed at the outer surface of the side plate 1,1, with the result that the surface of the pocket knife can be easily finished.

Claims (5)

1. A pocket knife having a knife blade that P, is foldable between a closed position wherein the blade is disposed within a cavity in the handle, and an open position, the blade being field in the open position by a lever biased against a base portion of the knife blade and pivoted by means received in recesses in the opposed side surfaces of the cavity, each side surface having therein a guide channel extend ing from the recess to an opening at a periph eral edge of the handle.

2. A knife according to claim 1 wherein the handle comprises two side plates which are spaced apart to define the cavity.

3. A knife according to claim 1 or claim 2 wherein the lever is biased by a spring -acting on the lever to provide a turning moment about the pivoto and to resist withdrawal of the pivot means along the guide channels.

4. A knife according to any one of claims 1 to 3-wherein disengageable interlocking means are provided to more securely hold the blade in the said open position.

5. A pocket knife comprising:

a pair of side plates; a knife blade which can be folded into the space between the side plates; a lever for locking the knife blade -in the open state and mounted or pivotal movement on a swing shaft; a flexible lead mounted between the side plate to apply to the pivoted lever, a turning moment centered around the shaft, so that the lever is urged against the base section of the knife blade; bearing recesses formed in the inner sur faces of the side plates to support the ends of the shaft, which bearing recesses do not penetrate as far as the outer surface of the side plates, and a guide channel which com municates with the bearing recess and ex tends as far as the peripheral edge of the side plate as a radial of the bearing section.

6 A pocket knife constructed and arranged substantially as hereinbefore described with reference to and as illustrated in the accom panying drawings.

Published 1988 at The Patent office, State House, 66/71 High Holborn, London WC 1 R 4TP. Further copies may be obtained from The Patent Office, Sales Branch, St Mary Cray, Orpington, Kent BR5 3RD.

Printed by Burgess.& Son (Abingdon) Ltd. Con. 1/87.