GB2063114A

GB2063114A - A power drill chuck attachment

Info

Publication number: GB2063114A
Application number: GB8036849A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1979-11-20
Filing date: 1980-11-17
Publication date: 1981-06-03
Also published as: GB2063114B; ES254512Y; IT8025510A0; BR8006770A; BE886247A; NL8005155A; ES254512U; FR2469972A1; DK455680A; DE2946697A1; IT1133987B

Abstract

An attachment for use with a power drill comprises a hollow elongate body (1) having an open end portion for fitting over the head (3) of the chuck when a drilling tool (4) is located in the chuck so that the tool is enclosed by, and out of contact with the body, the open end portion also having a ring of teeth (2) for interlocking with the teeth of the locking ring (6) of the chuck so that the body is rotatable with the chuck, the other end portion of the body having a receiving portion (9,10) which has an opening for receiving a tool bit (7), e.g. screwdriver bit. An insert (9) for the bit may be coupled by a torque limiting connection to the body. <IMAGE>

Description

SPECIFICATION A power drill chuck attachment This invention relates to a device, that may be used in association with a jaw chuck-type power drill, for screwing in fastening screws.

The operation carried out, for example for the insertion of a plug, requires firstly the production of a drill hole into which the plug is inserted. In order to anchorthe plug and to fasten an object, a fastening screw is then screwed into the plug. As a rule the fastening screw is screwed in by the power drill. For this purpose it is necessary to remove the drill tool, which is clamped in the power drill and used to produce the drill hole, and to clamp in a screwdriver attachment in its place. In the case of mass insertion this exchange process, if no additional power drill is available, has to be repeated in accordance with the number of plugs to be inserted.

The problem which underlies the invention is to provide a device for screwing in fastening screws which obviates the necessity of exchanging the drill tool and the screwdriver attachment.

According to the invention this is achieved by the fact that the device can be fitted over the drilling head of the jaw chuck and the clamped-in drill tool and has a toothed portion which interlocks with the toothed rim of the clamping nut of the jaw chuck, and by the fact that a receiving portion is arranged at the end of the device remote from the power drill, into which a screwdriver attachment can be inserted.

With the device according to the invention the following insertion process takes place. Firstly a hole corresponding to the outer diameter of the plug is drilled in the masonry with the drill tool clamped into the jaw chuck. After inserting the plug in the drill hole produced and positioning the fastening screw, the device is fitted over the drilling head and the clamped-in drill tool. Because of the toothed portion of the device, which interlocks with the toothed rim of the clamping nut of the jaw chuck, a torque transfer takes place from the power drill onto the screwdriver attachment inserted in the receiving portion. Thus, with the screwdriver attachment engaging in the screw head it is possible to screw the fastening screw into the plug without having to remove the drill tool.By means of the pressure necessary to screw in the fastening screw, the toothed portion of the device is prevented from disengaging from the toothed rim of the jaw chuck.

In a further arrangement of the invention, the receiving portion can be designed as a metal insert.

In this manner a high resistance to wear is achieved.

In a further development of the invention the receiving portion can have a flange abutting the end face of the device, as well as a bolt-shaped extension which projects into the interior of the device through a drill hole in the end face of the same and which has a thread and a nut, between which nut and the end face of the device a compression spring is arranged.

As a result of this arrangement a friction clutch is formed which, at too high a screw-in torque, for example when the fastening screw is completely screwed in, breaks the connection between the screwdriver attachment and the power drill. The sensitivity of the overload safeguard depends partly on the pressure and partly on the resilience of the compression spring arranged between the nut and the end face of the device.

In the case of devices used for screwing in fastening screws with a very high torque, in a further development of the invention the abutting end faces of the device and of the flange of the receiving portion have flat interengaging toothed portions.

This arrangement gives rise to an increase in the torque which is to be transferred from the power drill onto the screw driver attachment.

The present invention also provides an attachment for use with a power drill chuck having a toothed locking ring, the attachment comprising a hollow elongate body having an open end portion for fitting over the head of the chuck when a drilling tool is located in the chuck so that the tool is enclosed by, and out of contact with the body, the open end portion also having a ring of teeth for interlocking with the teeth of the locking ring of the chuck so that the body is rotatable with the chuck, the other end portion of the body having a receiving portion which has an opening for receiving a tool bit so that the bit extends axially with respect to, and away from the said other end of the body.

Two power drilled chuck attachments each constructed in accordance with the invention will now be described, by way of example, with reference to the accompanying drawings in which: Figure 1 illustrates a first attachment which has been mounted on the head of a drill chuck and into which a screwdriver bit has been inserted, and Figure 2 shows part of a second attachment.

Referring to the accompanying drawings and first of all to Figure 1, the attachment illustrated comprises a housing 1, preferably made of plastics material, which is elongate in form and has an open end portion provided with a ring of teeth 2. When the attachment is fitted over the head 3 of the chuck of a power drill the teeth on the toothed ring 2 interlock with the teeth, usually bevelled, of a locking or clamping ring or nut 6 of the chuck.

As shown in Figure 1 when the attachment has been located in position on the chuck the housing 1 shrouds a drill 4which has previously been clamped in the jaws of the chuck 3.

The other end portion of the housing 1 is provided with a recess into which has been located a metal insert 9. The insert 9 is non-rotatably mounted in the recess. For example this can be achieved by shaping the recess and the insert 9 so that they are polygonal, for example, square in cross-section.

The insert 9 has a recessed opening, which is also polygonal in section, non-rotatably to receive the end of a screwdriver bit 7.

As will be evident from Figure 1 the attachment can be mounted on the power drill chuckwithout removing the twist drill 4. Consequently, by alternately securing and removing the attachment from the chuck the power drill can be used both for screwdriving and also for drilling without exchanging tools in the chuck.

Referring now to Figure 2 the end part of the second attachment as illustrated is designed to protectthe power drill against overload and provides, in effect, a friction clutch which serves to break the torque transmission between the power drill and the screwdriver bit 7 if the torque becomes too high in operation. In this case, a recess in the end of the attachment housing receives an insert 10 which has an opening for receiving the screwdriver bit 7, and also a flange 11 which is rotatably mounted in the recess.

The flange 11 carries a bolt 12 which passes through the end portion of the attachment and is provided with a screw thread 13 for receiving two nuts 14. A compression spring 15 is mounted on the bolt 12 so that when the nuts are turned the flange is tightened against a transverse end face of the end portion of the attachment. That end face can be formed by an integral part of the end portion of the attachment or, alternatively, by a plate 17, made of metal which is non-rotatably mounted in the recess in the end portion of the housing.

It is preferred to use the plate insert 17 because when the plate becomes worn it can be easily removed and replaced by a fresh plate.

Two nuts 14 are provided so that the nut engaging the spring 15 can be used to tighten the flange against the said transverse face the other nut being used to lock the first nut in position after tightening.

By turning the nuts 14 and increasing or decreas ing the force applied bythe compression spring 15 the friction between the flange and the transverse end face can be increased or decreased as required.

That frictional force can also be increased when the screwdriver bit 7 is being used to drive a screw since the flange 11 will then be forced rearwardly and axially against the transverse face.

If a high torque is required for driving in a screw using the attachment illustrated in Figure 2 the flange 11 and the transverse end face can be provided with flat interengaging toothed portions 16, arranged in ring formation, in order to increase the frictional contact between them.

Claims

1. An attachment for use with a power drill chuck having a toothed locking ring, the attachment comprising a hollow elongate body having an open end portion forfitting over the head of the chuck when a drilling tool is located in the chuck so that the tool is enclosed by, and out of contact with the body, the open end portion also having a ring of teeth for interlocking with the teeth of the locking ring of the chuck so that the body is rotatable with the chuck, the other end portion of the body having a receiving portion which has an opening for receiving a tool bit so that the bit extends axially with respect to, and away from the said other end of the body.

2. An attachment as claimed in claim 1, in which the receiving portion comprises an insert provided with the said opening, the insert being non-rotatably mounted in a recess in the other end portion of the body.

3. An attachment as claimed in claim 1, in which the receiving portion is in the form of an insert provided with the said opening and having a flange which is rotatably mounted in a recess of the other end portion of the body, the flange carrying a bolt which passes through the end portion of the body, the bolt carrying a spring and receiving a nut so that the flange can be tightened against a transverse face of the other end portion of the body.

4. An attachment as claimed in claim 3, in which the flange and the transverse face have interengaging teeth formed thereon.

5. An attachment as claimed in claim 3 or claim 4, in which the transverse face is formed on a plate which is non-rotatably mounted in the recess.

6. A device, that may be used in association with a jaw chuck-type power drill, for screwing in fastening screws, wherein the device can be fitted over the drilling head of the jaw chuck and the clamped-in drill tool, the device has a toothed portion which interlocks with the toothed rim of the clamping nut of the jaw chuck, and the device has a receiving portion which is arranged at the end of the device remote from the power drill, into which a screw driver attachment may be inserted.

7. An attachment for use with a power drill chuck, the attachment being substantially as hereinbefore described with reference to and as illustrated by Figure 1 or Figure 2 of the accompanying drawings.