GB2366537A

GB2366537A - Method of making a housing for a tool and the housing so formed.

Info

Publication number: GB2366537A
Application number: GB0022137A
Authority: GB
Inventors: Graham Dewhurst
Original assignee: Ingersoll Rand Co Ltd
Current assignee: Ingersoll Rand Co Ltd
Priority date: 2000-09-09
Filing date: 2000-09-09
Publication date: 2002-03-13
Also published as: GB0022137D0

Abstract

A method of making a housing for a tool such as a percussive hand-held tool, includes providing a barrel (1), forming longitudinal fluid paths (2) in it, forming a cavity (3) in the barrel (1) to expose the fluid paths (2) and subsequently inserting an inner barrel part (1b) such as a sleeve to re-form the fluid paths (2). Transverse bores (6) are provided in the inner barrel part for fluid communication with the longitudinal fluid paths.

Description

2366537 METHOD OF MAKING A HOUSING FOR A TOOL AND THE HOUSING SO FORMED

This invention relates to a method of making a 5 housing for a tool and to the housing so formed.

In particular, the housing is for a hand-held tool such as a percussive tool or a machine mounted tool.

10 With percussive tools, whether they be hammers, rammers, chippers or other types of percussive tool, they all basically have a housing to which a handle is joined, the handle including an operating trigger. The housing has at least one longitudinal bore to supply compressed air 15 or other fluid to the working component of the tool.

Traditionally, the or each longitudinal bore is drilled or bored out from the end of the housing and transverse connecting bores have to be bored through the 20 solid housing.

According to one aspect of the present invention, there is provided a method of making a housing for a tool, the housing being of substantially barrel shape and 25 comprising an outer barrel part and an inner barrel part fitted axially in the outer barrel part, at least one fluid path being formed between the two parts.

According to another aspect of the present 30 invention, there is provided a tool having a housing, the housing being of substantially barrel shape and comprising an outer barrel part and an inner barrel part fitted axially in the outer barrel part, at least one fluid path being formed between the parts.

The housing could be made initially by providing a cored casting or by providing a single, solid part, boring or otherwise forming said at least one fluid path in the housing, broaching or otherwise forming a cavity 5 along a longitudinal portion of the housing to expose said at least one fluid path to the cavity, the remaining material forming said outer barrel part, and said inner barrel part being subsequently fitted.

10 Instead or as well, said inner barrel part can be formed with at least one external groove, for example in the form of a channel or keyway, that forms, when said inner barrel part is fitted in said outer barrel part, said at least one fluid path.

The outer barrel part may be made of forged, drawn or cast material and/or may be of aluminium.

The inner barrel part may be made of steel.

The outer barrel part may be shrunk, press fit or "glued" onto the inner barrel part.

one or both barrel parts could be made of a 25 thermoplastics material.

The invention also extends to a housing for a tool when made as defined above and to a tool having such a housing.

The tool may be a percussive tool.

The tool may be a hand-held or machine mounted tool such as a hammer, rammer, chipper, digger or breaker.

- 3 For a better understanding of the invention and to show how the same may be carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which:- Fig. 1A-is a diagrammatic end view of a housing for a tool illustrating a possible step in the manufacture thereof; 10 Fig. 1B is a diagrammatic sectional view taken on the line A-A in Fig. 1A; Fig. 2A is a diagrammatic view similar to Fig. 1A, showing a subsequent manufacturing step; Fig 2B is a diagrammatic sectional view taken on the line B-B of Fig. 2A and additionally showing part of a handle for the tool; 20 Fig. 3 is a diagrammatic side view, partly in section illustrating the tool in a near-complete form; and Fig. 4 is a diagrammatic end sectional view taken 25 through the housing and handle of the tool shown in Fig. 3.

Figures 1A and 1B show the basic concept of a hand held housing of a percussive tool and the first step of 30 manufacture shows a solid barrel 1 through which a plurality of longitudinal fluid paths 2 such as bores have been formed.

4 - In particular because of the difficulty in subsequently providing transverse fluid bores to connect with the longitudinal fluid path 2, the central section of the barrel 1 is taken out, for example by broaching, 5 thereby to expose the fluid paths 2 to an inner cavity 3, as illustrated in Figs. 2A and 2B. The result is the formation of an outer barrel 1A. Also illustrated in Fig. 2B is a handle 4 which houses a trigger 5 (Fig. 3).

10 As shown in Fig. 3, an inner barrel part 1B, already preformed with at least one transverse bore or fluid path 6 through its wall, is fitted within the outer barrel part 1A and is held in place at one end for example by a ci-rclip 7 and at the other end by, for example, a cap 15 arrangement 8.

As can be seen in both Figs. 3 and 4, this arrangement allows for the inner sleeve or barrel part 1B to again enclose the or each fluid path 2, whilst 20 providing access for compressed fluid to the working part of the percussive tool through the or each transverse fluid path 6.

Accordingly, the present construction eliminates the 25 necessity to machine the transverse fluid paths such as bores in situ and also allows a choice of materials more suited to the function and strength requirements of the tool.

30 As mentioned previously, the inner barrel part 1B can be provided with at least one external groove (not shown) in addition to or instead of the drilled out portion(s) of the outer barrel part 1A in order to form the or each fluid path 2.

Claims

1. A method of making a housing for a tool, the housing being of substantially barrel shape and 5 comprising an outer barrel part and an inner barrel part fitted axially in the outer barrel part, at least one fluid path being formed between the two parts.

2. A method according to claim 1, wherein the 10 housing is formed from a single, solid part, and said at least one fluid path is bored or otherwise formed in the housing, and a cavity is broached or otherwise formed along a longitudinal portion of the housing to expose said at.least one fluid path to the cavity, the remaining 15 material forming said outer barrel part, and said inner barrel part being subsequently fitted.

3. A method according to claim 1 or 2, wherein said inner barrel part is formed with at least one 20 external groove, that forms, when said inner barrel part is fitted in said outer barrel part, said at least one fluid path.

4. A method according to any one of the preceding 25 claims, wherein the outer barrel part is made from forged, drawn or cast material and/or is of aluminium.

5. A method according to any one of the preceding claims, wherein the inner barrel part is of steel.

6. A method according to claim 1, 2 or 3, wherein one or both barrel parts is/are made of a thermoplastics material.

7. A method according to any one of the preceding claims, wherein the outer barrel part is shrunk, press fit or glued onto the inner barrel.

5

8. A method according to any one of the preceding claims, wherein said inner barrel part is preformed with at least one transverse fluid path through its wall for communication with said at least one fluid path that is formed between said two parts.

9. A method of making a housing for a tool, substantially as hereinbefore described, with reference to the accompanying drawings.

15

10. A housing according to claim 10 for a tool when made in accordance with any one of the preceding claims.

11. A housing for a tool, substantially as hereinbefore described with reference to the accompanying 20 drawings.

12. A tool including a housing according to claim 9 or 10.

25

13. A tool having a housing, the housing being of substantially barrel shape and comprising an outer barrel part and an inner barrel part fitted axially in the outer barrel part, at least one fluid path being formed between the parts.

14. A tool according to claim 13, wherein said inner barrel part is formed with at least one external groove, that forms, when said inner barrel part is fitted in said outer barrel part, said at least one fluid path.

15. A tool according to claim 13 or 14, wherein said inner barrel part is preformed with at least one transverse fluid path through its wall for communication with said at least one fluid path that is formed between 5 said two parts.

16. A tool according to claim 12, 13, 14 or 15 and being a percussive tool.

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17. A tool according to claim 16 and being a hammer, rammer, chipper, digger or breaker.

18. A tool, substantially as hereinbefore described with reference to the accompanying drawings.