GB2139124A

GB2139124A - Device for portable drilling machines, to collect chipped material

Info

Publication number: GB2139124A
Application number: GB08404505A
Authority: GB
Inventors: Lars Ljungkrantz
Original assignee: Trelleborg AB
Current assignee: Trelleborg AB
Priority date: 1983-02-24
Filing date: 1984-02-21
Publication date: 1984-11-07
Also published as: FR2541617A1; SE8301011L; SE8301011D0; GB8404505D0; FR2541617B3; DE8405583U1

Abstract

A device for portable hammer drilling machines having a bayonet joint type chuck for the drill, for collecting chipped material comprises a bellows type receptacle (13) of resilient material, surrounding the drill (12) coaxially, which is open at the front end (14) thereof and can be engaged at said end with the surface wherein drilling is to take place. The receptacle is closed at the rear end thereof positioned adjacent to the drilling machine, by means of a rigid end wall (15) which has a central aperture (16) and is rotatably mounted on the drill shaft (17) to be guided thereon. In order to restrain the receptacle from rotating together with the drill the end wall is guided for axial displacement on a depth abutment (11) on the drilling machine at a portion of the end wall, projecting radially therefrom and displaceably receiving the depth abutment. <IMAGE>

Description

SPECIFICATION Device for portable drilling machines, to collect chipped material The invention relates to a device in portable hammer drilling machines having a bayonet joint type chuck for the drill, for collecting chipped material, said device comprising a bellows type receptacle of resilient material, preferably rubber, surrounding the drill coaxially, which is open at the front end thereof and can be engaged at said end with the surface wherein drilling is to take place, and is closed at the rear end thereof, positioned adjacent to the drilling machine.

When one is drilling in a surface the chipped material which may comprise dust or drillings, will be collected in the bellows type receptacle. Accordingly, it is avoided that the chipped material is spread in the surroundings and makes things dirty in the vicinity of the working place or causes damage to such things. However, by means of such a collecting device it is prevented above all that the chipped material falls down onto the person who is drilling, which otherwise can hardly be avoided when drilling in a ceiling. Then, the chipped material can penetrate easily into the eyes and cause damage thereto if no protecting glasses are being used.

Several collecting devices have already been proposed. Thus, there are described in DE-A2,317,779, DE-A-2,356,565, and DE-A-2,434,641, and in US-A-3,339,435 collecting devices with a bellows or similar type receptacle which is attached to the drilling machine at the rear end of the receptacle. A disadvantage of these prior art collecting devices is that it is relatively troublesome to mount the collecting device, and that such mounting may require adjustment of the collecting device to the particular type of drilling machine to which the collecting device is to be mounted, and furthermore, that the collecting device must be removed when the drill is to be exchaged.

A collecting device which is not mounted to the drilling machine proper, is described in DE-A 2,404,504. It is passed onto the drill but it must be kept in the proper position manually, which is an obvious disadvantage, because it is in most cases desired to use both hands for handling the drilling machine, particularly when drilling in a ceiling by means of a hammer drill.

In ordertoovercomethedisadvatagesofthe prior art collecting devices, the invention provides a collecting device of the kind referred to above, which is characterised in that the bellows type receptacle at a central aperture in a rigid end wall at the rear end of the receptacle is rotatably mounted to the drill shaft to be guided thereon, and that the end wall for restraining the receptacle from rotating together with the drill is guided for axial displacement on a depth abutment of the drilling machine at a portion of the end wall, projecting radially therefrom and displaceably receiving the depth abutment.

An embodiment of this collecting device will be described below with reference to the accompanying drawing wherein the single figure is an axial cross-sectional view of the collecting device of the invention mounted to a hammer drilling machine, parts of which are fragmentarily shown in side view.

The hammer drilling machine shown in the draw ing comprises a drill chuck 10 which in a hammer drilling machine usually is of the bayonet-joint type.

The drilling machine also is provided with an adjustable depth abutment 11 which extends in the axial direction of the chuck and can be adjusted axially for determining different drilling depths by engagement of the depth abutment with the surface wherein drilling takes place, and thus preventing the continued penetration of the drill into said surface. In the drawing there is shown a drill 12 secured to the chuck 10.

The collecting device according to the invention comprises a moulded bellows type receptacle 13 of rubber without any inserts therein. The receptacle is soft and can be compressed elastically from the normal position shown. The receptacle is adapted to be engaged at one end 14 thereof, the front end, with the surface wherein drilling is to take place, while the receptacle at the opposite end, the rear end, is provided with a circular receptacle holder 15, prefer ably of a plastic material having good bearing properties such as Nylon, said holder being attached to the receptacle.The receptacle holder forms an end wall at the rear end of the receptacle, having a central circular through aperture 16, and the collect ing device is mounted to the drilling machine by the receptacle holder 15 being passed at said aperture onto the shaft 17 of the drill 12, said shaft of drills adapted to be attached to a chuck of the bayonet joint type having the same diameter independent of the diameter of the bore, such that one and the same collecting device canoe used for drills of different diameters. The holder 15 has a play in the drill shaft 17, which can be one or two tenths of a millimetre, and the holder 15 with the receptacle 13 is thus rotatably mounted to the shaft 17.In orderthatthe holder with the receptacle will not rotate together with the drill, the holder is provided with a collar 18 or forms such a collar, which partly surrounds the chuck 10 spaced therefrom, and forms a radially projecting lug 19 which is mounted displaceably on the depth abutment 11. This abutment passes through an aperture in the lug 19 but as an alternative the lug can be formed as a fork which straddles the depth abutment 11.

At drilling, the end 14 of the bellows type recepta cle 13 is engaged with the surface in which drilling is to take place, and accordingly all chipped material will be received by the receptacle closed at the rear end thereof by means of the holder 15, the recepta cle being compressed axially as the drill penetrates into the surface wherein drilling takes place. The collecting device is restrained from rotating by the engagement of the holder within the depth abut ment 11.

When the drill 12 is to be exchanged the chuck 10 is easily available for operating same when remov ing the old drill and fitting the new drill. Thus, it is not necessary to dismount the collectng device from the drilling machine when the drill is to be ex changed. The bellows type receptacle preferably has such length that it can enclose the drill of the greatest length. Then, the receptacle can be cut at the desired position for use in connection with drills of shorter lengths, if the bellows type receptacle otherwise should be compressed too much at the drilling depth associated with such shorter drills.

As mentioned above the holder 15 preferably is made of a plastic material having good bearing properties, but also other plastic materials can be used if the aperture 16 of the holder is provided with a bushing. Further modifications can of course be made in the embodiment shown and described herein within the scope of the following claims.

Claims

1. A device for a portable hammer drilling machine having a bayonet joint tyoe checkforthe drill, for collecting chipped material, said device comprising a bellows type receptacle of resilient material surrounding the drill coaxially, which is open at the front end thereof and can be engaged at said end with the surface wherein drilling is to take place, and which is closed at the rear end positioned adjacent to the drilling machine, characterised in that the bellows type receptacle at a central aperture in a rigid end wall at the rear end of the receptacle is rotatably mounted on the drill shaft to be guided thereon, and that the end wall for restraining the receptacle from rotating together with the drill, is guided for axial displacement on a depth abutment on the drilling machine at a portion of the end wall, projecting radially therefrom and displaceably receiving the depth abutment.

2. A device as claimed in Claim 1, in which said resilient material comprises rubber.

3. A device as claimed in Claim 1 or Claim 2, in which the aperture of the end wall is provided with a bushing.

4. A collecting device for use with a hammer drill, substantially as hereinbefore described with reference to the accompanying drawing.

5. A hammer drill provided with a device according to any preceding Claim.

6. The features herein described, or their equivalents, in any patentably novel selection.