EP1197303A1

EP1197303A1 - Quick clamping system for hand-operated tools

Info

Publication number: EP1197303A1
Application number: EP00830670A
Authority: EP
Inventors: Alessio Tacchini
Original assignee: Dima Star Srl
Current assignee: Dima Star Srl
Priority date: 2000-10-13
Filing date: 2000-10-13
Publication date: 2002-04-17

Abstract

Quick clamping system for hand-operated tools, such as hammers, that comprises two basic members, a head (3) and a wedge (7) which can be fitted into each other when the head (3) is introduced into the slot of the tool (1); said two members (3) and (7) being provided with a plurality of corresponding cusp-shaped teeth (11, 25) that mutually engage upon introduction of the wedge-shaped member (7) into the head member (3), whereby an effective and quick clamping is obtained.

Description

The present invention relates to a quick clamping system for hand-operated tools, such as hammers and the like, that is tools to which a handle is to be secured for use.
It is known that, for such hand-operated tools, such as hammers and the like, it is common practice introducing the handle head into the proper slot of the tool and, thereafter, increasing the coupling stability by introducing at least one nail into said head for widening said head and make it adhere in more stable way against said slot of the hand-operated tool.
That operation is not always effective: prolonged use of the tool weakens said coupling, so that often it is necessary to take other measures, e. g. inserting another nail into said head to try to restore the coupling.
The most serious drawback is however that said coupling is scarcely reliable. For instance, in case of a hammer, vigorous and prolonged use of the tool may result in the tool becoming detached from the handle with serious dangers for people and damages for things.
The object of the present invention is to overcome said drawbacks by providing a simple and practical clamping system which allows reliably securing such a tool to the handle, so that the tool can be used without any problem.
The essential features of the present invention will become apparent from the appended claims.
The present system and its component parts will now be described in detail with particular reference to the accompanying drawings, given by way of non limiting example, in which:

Fig. 1 is an exploded perspective view of the two parts forming the system;
Fig. 2 is an exploded side view of the two parts shown in Fig. 1;
Fig. 3 is a view showing the manner in which the two parts of the system engage each other, the hand-operated tool being omitted; and
Fig. 4 is a schematic side elevation showing how a hammer is clamped to the handle by using the present system.

For a better clarity, we refer here to a hand-operated tool consisting of a hammer 1 to which the handle is to be clamped by the system of the invention. It is clear that said hammer 1 is a non-limiting example and represents in broad terms a tool to which the system of the invention can be applied.
Referring to the accompanying drawings, the system of the invention essentially comprises two parts: head 3 of hammer handle 5, and an external clamping member 7, arranged to be applied to said handle head 3.
Said handle head 3 is made by copying thereon the profile of the slot of hammer 1 or other hand-operated tool into which the head is to be introduced, and by providing therein a longitudinal central hollow 9, transversal to the axis of hammer 1. Said hollow 9 has the shape of a sunken wedge and has a plurality of-downward inclined cusp teeth 11. Hollow 9 ends at its bottom into a substantially rectangular chamber 13, capable of giving a resiliency to the two handle portions 15 created by said hollow 9.
Said head 3 is substantially frusto-conical in upward direction in order to make its insertion into the hammer slot easier and to improve its stability. In other words, the head has, from the bottom to the top, a straight base 17, a tapered portion 19 and an upper straight portion 21, of reduced size with respect to base 17.
Said head 3 has the same cross-sectional shape (elliptical, oval or cylindrical) as the slot into which it is to be introduced.
External clamping member 7 comprises a wedge-shaped portion 23, with a profile corresponding to the profile created in hollow 9 of head 3, that is with a plurality of upward directed cusp teeth 25, capable of fitting into the corresponding recesses created by teeth 11 of head member 3.
Also clamping member 7 comprises an upper portion 27, with the same shape as the slot, from which said wedge-shaped portion 23 projects. Upper portion 27 is intended to come in contact with the planar upper portion of head member 3.
The system operation is obvious: head member 3 is introduced into the slot in hammer 1 or other tool to which the handle is to be secured, then wedge shaped member 7 is introduced into said head member whereby it becomes clamped with handle 5.
By said system head 3 can no longer become disengaged since wedge 7 hinders flexion of the coupling flanges, which in any case always remain under the bevel of a triangle. Moreover, the system allows an integral unit to be formed with handle 5 of hammer 1 or other hand-operated tool, whereby a greater compactness and rigidity of the mounting is obtained.

Claims

Quick clamping system for hand-operated tools, such as hammers and the like, characterised in that it comprises two basic members, a head member (3) and a wedge-shaped member (7) arranged to fit into each other when the head member (3) has been introduced into the slot of the tool (1) to which the handle is to be applied; said two members (3) and (7), arranged to be introduced into the slot of the tool (1), being provided with a plurality of cusp teeth (11, 25) arranged to mutually engage upon introduction of the wedge-shaped member (7) into the head member (3), whereby an effective and quick clamping of the tool (1) to the handle (5) is obtained.
A clamping system as claimed in claim 1, wherein the head member (3) is made by copying thereon the profile of the slot of the tool 1 into which the head is to be introduced, and by providing therein a longitudinal central hollow (9), transversal to the axis of the tool (1); said hollow (9) having the shape of a sunken wedge with a plurality of downward inclined cusp teeth (11), said hollow (9) ending at its bottom with a substantially rectangular chamber (13), capable of giving a resiliency to the two handle portions (15) created by said hollow.
A clamping system as claimed in claim 1, wherein said head member (3) is substantially frusto-conical in upward direction, that is, it has, from the bottom to the top, a straight base portion (17), a tapered portion (19) and an upper portion (21), which also is straight but smaller than the base (17).
A clamping system as claimed in claim 1, wherein said external clamping member (7) comprises a wedge-shaped portion (23) with a profile corresponding to the profile created in the hollow (9) of the head (3), that is with a plurality of upward directed cusp teeth (25) capable of fitting into the corresponding recesses created by the teeth (11) of the head member (3); said wedge-shaped portion (23) having a planar upper portion (27), with a shape similar to the upper portion of the head member (3) and coming into contact therewith when the head member (3) is introduced into the slot.