Torque transferring device for use with a power tool

Abstract

The present specification relates to a torque transferring device for power tools, comprising a first portion comprising a first engaging structure arranged at a front end of the first portion and adapted to engage a corresponding mating structure to transfer torque thereto, and a second portion comprising a second engaging structure for connection to the output shaft of a power tool arranged at a rear end portion of the second portion, wherein the second engaging portion comprises an open cavity adapted to receive the output shaft of a power tool. The device further comprising a pin arranged at least partly in the open cavity, wherein the pin is arranged to extend in an axial direction and further arranged to, in use, engage a hole formed in the power tool output shaft.

Claims

1. A torque transferring device for a power tool, comprising a first portion comprising a first engaging structure arranged at a front end of said first portion and adapted to engage a corresponding mating structure to transfer torque thereto, and a second portion comprising a second engaging structure for connection to an output shaft of a power tool arranged at a rear end portion of said second portion, wherein said second portion comprises an open cavity adapted to receive said output shaft of a power tool, said device further comprising a pin arranged at least partly in said open cavity, wherein said pin is arranged to extend in an axial direction and further arranged to, in use, engage a hole formed in said power tool output shaft, wherein said pin comprises a body portion and a head portion, wherein said head portion is adapted to, in use, extend into said hole formed in said power tool output shaft.

2. Torque transferring device according to claim 1, wherein said pin extends along a center axis A-A of said torque transferring device and wherein said hole in said power tool output is a center hole.

3. Torque transferring device according to claim 1, wherein said head portion is conical.

4. Torque transferring device according to claim 1, wherein a total length of said pin lies in a range 0.5-15 mm.

5. Torque transferring device according to claim 1, wherein said open cavity comprises a delimiting wall, wherein a hole is provided in said wall opening into said open cavity, and wherein said body portion of said pin is arranged in said hole.

6. Torque transferring device according to claim 5, wherein a surface of said delimiting wall facing said open cavity is substantially flat and extends in a direction perpendicular to a center axis A-A of said torque transferring device.

7. Torque transferring device according to claim 1, further comprising at least one magnet for biasing said pin against a ferromagnetic output shaft by means of a magnetic force.

8. Torque transferring device according to claim 7, wherein said at least one magnet is arranged in a hole provided in said delimiting wall and opening into said open cavity.

9. Torque transferring device according to claim 1, wherein the device further comprises a freely rotatable outer sleeve for operator protecting purposes.

10. Torque transferring device according to claim 9, wherein said freely rotatable outer sleeve is made of an electrically insulating material.

11. Torque transferring device according to claim 1, further comprising an inner insulating element, wherein said inner insulating element is rotatably coupled to said first engaging structure and to said second engaging structure such that a torque may be transferred there between, and wherein said inner insulating element is made of an electrically insulating material, such that an electrical insulation is formed between said first engaging structure and said second engaging structure for operator protecting purposes.

12. Torque transferring device according to claim 1, wherein said torque transferring device is a component chosen from the group socket, bit holder, quick change adapter and extension.

13. Torque transferring device according to claim 12, wherein said device is a socket or a bit holder, and wherein said first portion arranged at a front end thereof adapted to engage a corresponding mating structure to transfer torque thereto, is a portion adapted to engage a nut or a bit.

14. Torque transferring device according to claim 12, wherein said device is a quick change adapter or an extension, and wherein said first portion arranged at a front end thereof adapted to engage a corresponding mating structure to transfer torque thereto, is an adapter or extension output adapted to engage a bit, socket or bit holder.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention will be described in the following illustrative and non-limiting detailed description of exemplary embodiments, with reference to the appended drawing, on which

(2) FIG. 1a is a cross sectional view of an exemplary torque transferring device according to a first embodiment.

(3) FIG. 1b is a cross sectional view of an exemplary torque transferring device according to a first embodiment.

(4) FIG. 2 is a cross sectional view of an exemplary torque transferring device according to a second embodiment.

(5) All figures are schematic, not necessarily to scale and generally only show parts which are necessary in order to elucidate the invention, wherein other parts may be omitted or merely suggested.

DETAILED DESCRIPTION

(6) An exemplary torque transferring device 1 for use with a power tool according to a first embodiment is shown arranged on a power tool output shaft OS in a cross sectional view in FIG. 1. The illustrated exemplary device 1 is a socket 1 comprising a first portion 10 and a second portion 20. A first engaging structure 13 is arranged at a front end 10a of the first portion 10 and adapted to engage a nut to transfer torque thereto, i.e. to tighten a joint. The second portion 20 similarly comprises a second engaging structure 22 arranged at a rear end 20b of the socket and comprisingor formed byan open cavity 11 adapted to receive the output shaft OS of the power toolin the illustrated embodiment a square female output OS.

(7) In order to improve the engagement and guiding, the socket further comprises a pin 40 extending through this open cavity 11 in an axial direction A-A. The pin 40 is arranged to in use, as shown in FIG. 1, engage the hole H formed in the power tool output shaft OS. The hole H in the illustrated output shaft OS is a cone shaped center holei.e. a hole provided in the output shaft in order to facilitate machining of the shaft during manufacturing by means of engaging a correspondingly cone shaped bar for example during lathing. The pin of the embodiment illustrated in FIG. 1 comprises a body portion 40a and a conical head portion 40b, where the head portion is adapted to, in use as shown in FIG. 1, extend into the correspondingly conical hole H.

(8) The body portion 40a of the pin is arranged in a blind hole 24 provided in a delimiting wall 23 forming a bottom of the open cavity 22the wall 23 is substantially flat and extends in a direction perpendicular to the center axis A-A. It follows that the head portion 40a only is arranged in the open cavity.

(9) The length of the head portion is adapted in order to ensure that the head portion 40a makes contact with the cone shaped surface of the hole H of the output shaft before the flat portion F of the tool square OS comes into contact with the wall 23.

(10) In order to provide an even further engagement, the illustrated embodiment further comprises magnets 30a; 30b arranged in blind holes provided in the delimiting wall 23 opening into the cavity 22 for attracting the commonly ferromagnetic output shaft OS by means of a magnetic force against the pin 40.

(11) Turning to FIG. 1b, a similar socket is shown in a cross sectional view. As the socket of FIG. 1, the socket 1 of FIG. 1b comprises a first engaging structure 13 adapted to engage a nut to transfer torque thereto and a second engaging structure 22 formed by an open cavity 11 adapted to receive the output shaft OS of the power tool (not shown). The socket further comprises a pin 40 extending through this open cavity and arranged to in use, as shown in FIG. 1, engage the hole H formed in the power tool output shaft OS. The pin comprising a body portion 40a and a conical head portion 40b, where the head portion is adapted to, in use extend into the hole H. The illustrated embodiment however differs from the embodiment of FIG. 1a in that no magnets are provided.

(12) Turning to FIG. 2, another exemplary torque transferring device 1 according to a third embodiment is shown in a cross sectional view arrange don a tool output shaft. The illustrated exemplary device 1 is however an extension 1. Similarly to the embodiments in FIGS. 1a and b, the extension comprises a first portion 10 and a second portion 20. A first engaging structure 13 is arranged at a front end 10a of the first portion 10 and adapted to engage a socket to tighten a joint. The second portion 20 comprises a second engaging structure 22 arranged at a rear end 20b of the extension and comprisingor formed byan open cavity 11 adapted to receive the output shaft OS of the power tool.

(13) Also as described above, the extension of FIG. 2 comprises a pin 40 extending through the open cavity 11 in an axial direction A-A.

(14) The pin 40 comprises a cylindrical body portion arranged in a blind hole 24 provided in the wall 23 and a conical head portion, where the head portion is adapted to, in use, extend into a correspondingly conical hole H in the output shaft OS.

(15) However, in the third embodiment, for operator protecting purposes, an electrical insulation is formed between the first engaging structure 13 and the second engaging structure 22, and hence between the joint and the tool and the hand of the operator holding the tool. This by means of an inner insulating element 50, made of an electrically insulating material arranged between and rotatably coupled to the first engaging structure and the second engaging structure such that a torque may be transferred there between.

(16) In order to further enhance the operator protection, the extension of the illustrated embodiment in FIG. 2 includes a freely rotatable outer sleeve 60 made of an electrically insulating material and provided on the outside of the extension. It should be noted that the additional protective features shown in FIG. 2i.e. the insulating sleeve and element, may just as well be applied to the sockets shown in FIGS. 1a and b.

(17) While the invention has been illustrated and described in detail in the drawings and foregoing description, such illustration and description are to be considered illustrative or exemplary and not restrictive; the invention is not limited to the disclosed embodiments. The skilled person understands that many modifications, variations and alterations are conceivable within the scope as defined in the appended claims. For example, the invention may apart from the sockets and extension adapter of the illustrated embodiments just as well be realized as a (quick change) adapter, or as a bit holder.

(18) Additionally, variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure and the appended claims. In the claims, the word comprising does not exclude other elements or steps and the indefinite article a or an does not exclude a plurality. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. Any reference signs in the claims should not be construed as limiting the scope of the claims.