GB2142269A - Hand tool - Google Patents

Abstract

A hand tool (e.g. a plasterer's hawk) comprises a flat plate-like member (2), a threaded stem (5) secured thereto and extending from one side thereof and a handle (7) within which is located a captive nut (10) to engage the threaded stem (5). When fully tightened, an abutment (11) (which may be the nut (10)) within the handle (7) abuts abutment means (6) on the stem (5). The handle (7) at least at the end (13) towards the plate-like member (2), is formed from a resilient material, the distance from the end (13) to the abutment (11) within the handle being such that on screwing of the captive nut (10) along the stem (5), the end (13) of the handle contacts the plate-like member (2) marginally before the abutment (11) on the handle tightens on to the abutment (6) on the stem (5), whereby when fully tightened the end (13) of the handle is urged into positive engagement with the plate-like member (2). <IMAGE>

Description

SPECIFICATION Hand tool This invention relates to hand tools, and is particularly, though not necessarily exclusively concerned with hand tools for plasterers such as a so-called plasterer's hawk.

An existing plasterer's hawk is formed by a generally square or rectangular plate or blade, having, centrally of its undersurface, a boss secured in place, e.g., by rivetting. In the boss is a square hole in which a brass nut is held captive, and there is provided a handle, normally of wood, through which extends a bolt which screws into the nut, there being a resilient disc, e.g., of sponge rubber, interposed between the end of the handle and the boss, the disc being there for the comfort of the user, and to provide some assistance in preventing overtightening of the handle. Despite this, overtightening frequently occurs, and as the boss is normaily formed from an aluminium alloy, the nut is caused to turn in the boss, and then the plate or blade can turn on the handle in use, even when the handle is fully tightened.Other plasterer's hawks, although of different precise construction, have the common fault of the plate or blade becoming free to spin on the handle.

The object of the present invention is to provide a means of connecting a hand tool handle in place which avoids the disadvantages referred to above.

According to the present invention, a hand tool comprises a flat plate-like member, a threaded stem secured to and extending from one side of the plate-like member, an abutment on the threaded stem, and a handle within which.is located a captive nut to engage the threaded stem, the nut or an abutment means formed within the handle being adapted to be brought into tight engagement with the abutment means on the screw threaded stem, and the handle at least at the end towards the plate-like member being formed from a resilient material, the distance from that end of the handle to the position of the nut or the abutment means within the handle being such that on screwing of the nut along the stem, the end of the handle contacts the plate-like member marginally before the nut or the abutment means on the handle tightens on to the abutment means on the screw threaded stem, and whereby on tightening of the nut or abutment means on the handle against the abutment on the stem, the end of the handle is urged into positive engagement with the plate-like member.

When the hand tool is a plasterer's hawk, the plate-like member may be the operative plate or blade, and when the handle will be located generally centrally and extending perpendicularly from the rear face. It will however be understood that the plate-like member could be secured to the operative portion of other hand tools.

Preferably the screw threaded stem is a setscrew extending through the plate-like member, the plate-like member having a countersunk hole and whereby the set-screw head lies flush with the surface. It is further preferred that the abutment on the stem is formed by a lock-nut securing the set-screw to the platelike member.

The handle may be formed in its entirity as a moulding of a resilient tough plastics material, and moulded with an internal fitment to receive the captive nut which fitment can also serve as the abutment means within the handle to be tightened on to the lock-nut constituting that abutment on the threaded stem. It is also preferred that the end of the handle towards the plate-like member is flared, the flared end being provided with a rim to contact the plate-like member. Such a flared end adds considerably to the comfort of the user.

By locating the fitment at a distance within the handle such that on screwing the captive nut along the set-screw, the rim contacts the plate-like member marginally before the abutment in the handle tightens on to the locknut, there is the two-fold advantage that the force exerted between the rim and the platelike member on the tightening of the abutment in the handle on to the lock-nut, provides two points of resistance against rotation of the handle with respect to the plate-like member, and by having the rim contact the plate-like member marginally before there is contact between the abutment on the handle and the lock-nut, there is eliminated the possibility of the captive nut being pulled through the fitment, or otherwise loosened in the fitment.

One embodiment of the invention will now be described with reference to the accompanying drawings in which: Figure 1 is a sectional side elevation of a plasterer's hawk constructed in accordance with the invention; Figure 2 is a rear elevation of the plasterer's hawk of Fig. 1.

In the drawings, a plasterer's hawk 1 has a flat rectangular plate or blade 2. Centrally of the plate or blade is a countersunk hole 3 to receive the head 4 of a set screw 5, with the end face of the head lying flush with the face of the plate or blade. Behind the plate or blade, a lock nut 6 is screwed on to the stem and into engagement with the rear face of the plate or blade.

A handle 7 is formed as a moulding of a tough, resilient plastics material, and has an internal formation 8 which, to one side, forms a housing 9 for a captive nut 10, and to the other side an abutment 11 to engage the lock nut 6.

The end of the handle 7 towards the plate or blade 2 has a flared portion 1 2 with a rim 13, the distance between the face of the rim and the end of the abutment 11 being such that on screwing of the handle by its captive nut on to the set screw, the rim 1 3 contacts the rear face of the plate or blade 2 marginally before the abutment 11 contacts the lock nut 6. Further tightening of the handle then brings the abutment 11 into contact with the lock nut 6, and when further tightening is prevented.

There is therefore eliminated completely the pulling of the captive nut through the housing or otherwise being loosened, by virtue of the two points of resistance against over-tightening of the handle, i.e. between the rim on the flared end of the handle and plate or blade, and by the contact between the abutment means within the handle and the lock nut on the stem.

1. A hand tool comprising a flat plate-like member, a threaded stem secured to and extending from one side of the plate-like member, an abutment on the threaded stem, and a handle within which is located a captive nut to engage the threaded stem, the nut or an abutment means formed within the handle being adapted to be brought into tight engagement with the abutment means on the screw threaded stem, and the handle at least at the end towards, the plate-like member being formed from a resilient material, the distance from that end of the handle to the position of the nut or the abutment means within the handle being such that on screwing of the nut along the stem, the end of the handle contacts the plate-like member marginally before the nut or the abutment means on the handle tightens on to the abutment means on the screw threaded stem, and whereby on tightening of the nut or abutment means on the handle against the abutment on the stem, the end of the handle is urged into positive engagement with the plate-like member.

2. A hand tool as in Claim 1 and in the form of a plasterer's hawk, wherein the platelike member is the operative plate or blade, and the handle is located generally centrally and extends perpendicularly from the rear face.

3. A hand tool as in Claim 1 or Claim 2, wherein the screw threaded stem is a setscrew extending through the plate-like member, the plate-like member having a countersunk hole and whereby the set-screw head lies flush with the surface.

4. A hand tool as in Claim 3, wherein the abutment means is a lock nut securing the set-screw to the plate-like member.

5. A hand tool as in any of Claims 1 to 4, wherein the handle is formed in its entirity as a moulding of a resilient tough plastics material, and moulded with an internal fitment to receive the captive nut which fitment can also serve as the abutment means within the handle to be tightened on to the lock-nut constituting the abutment on the threaded stem.

6. A hand tool as in Claim 5, wherein the end of the handle towards the plate-like member is flared, the flared end being provided with a rim to contact the plate-like member, 7. A hand tool as in Claim 5 or Claim 6, wherein the fitment is at a distance within the handle such that on screwing the captive nut along the set-screw, the rim contacts the plate-like member marginally before the abutment in the handle tightens on to the lock nut.

8. A hand tool substantially as hereinbefore described with reference to the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (8)

**WARNING** start of CLMS field may overlap end of DESC **. or blade 2 has a flared portion 1 2 with a rim 13, the distance between the face of the rim and the end of the abutment 11 being such that on screwing of the handle by its captive nut on to the set screw, the rim 1 3 contacts the rear face of the plate or blade 2 marginally before the abutment 11 contacts the lock nut 6. Further tightening of the handle then brings the abutment 11 into contact with the lock nut 6, and when further tightening is prevented. There is therefore eliminated completely the pulling of the captive nut through the housing or otherwise being loosened, by virtue of the two points of resistance against over-tightening of the handle, i.e. between the rim on the flared end of the handle and plate or blade, and by the contact between the abutment means within the handle and the lock nut on the stem.

1. A hand tool comprising a flat plate-like member, a threaded stem secured to and extending from one side of the plate-like member, an abutment on the threaded stem, and a handle within which is located a captive nut to engage the threaded stem, the nut or an abutment means formed within the handle being adapted to be brought into tight engagement with the abutment means on the screw threaded stem, and the handle at least at the end towards, the plate-like member being formed from a resilient material, the distance from that end of the handle to the position of the nut or the abutment means within the handle being such that on screwing of the nut along the stem, the end of the handle contacts the plate-like member marginally before the nut or the abutment means on the handle tightens on to the abutment means on the screw threaded stem, and whereby on tightening of the nut or abutment means on the handle against the abutment on the stem, the end of the handle is urged into positive engagement with the plate-like member.

2. A hand tool as in Claim 1 and in the form of a plasterer's hawk, wherein the platelike member is the operative plate or blade, and the handle is located generally centrally and extends perpendicularly from the rear face.

3. A hand tool as in Claim 1 or Claim 2, wherein the screw threaded stem is a setscrew extending through the plate-like member, the plate-like member having a countersunk hole and whereby the set-screw head lies flush with the surface.

4. A hand tool as in Claim 3, wherein the abutment means is a lock nut securing the set-screw to the plate-like member.

5. A hand tool as in any of Claims 1 to 4, wherein the handle is formed in its entirity as a moulding of a resilient tough plastics material, and moulded with an internal fitment to receive the captive nut which fitment can also serve as the abutment means within the handle to be tightened on to the lock-nut constituting the abutment on the threaded stem.

6. A hand tool as in Claim 5, wherein the end of the handle towards the plate-like member is flared, the flared end being provided with a rim to contact the plate-like member,

7. A hand tool as in Claim 5 or Claim 6, wherein the fitment is at a distance within the handle such that on screwing the captive nut along the set-screw, the rim contacts the plate-like member marginally before the abutment in the handle tightens on to the lock nut.

8. A hand tool substantially as hereinbefore described with reference to the accompanying drawings.