WO2008041011A1

WO2008041011A1 - Drill bit setting device

Info

Publication number: WO2008041011A1
Application number: PCT/GB2007/003810
Authority: WO
Inventors: Stuart Harold Turner; Iain Bradfield
Original assignee: Turner Intellectual Property Limited
Priority date: 2006-10-06
Filing date: 2007-10-05
Publication date: 2008-04-10
Also published as: WO2008041011A8; GB0619758D0; GB2442790A

Abstract

A drill bit setting device (40) includes a holder (42) for holding in use a drill bit (10) substantially in alignment along a longitudinal axis (76) of the bit (10). The drill bit setting device (40) includes first limit means (70) for limiting movement of the bit (10) along the axis (76) and second limit means (72) for limiting rotational movement of the bit (10) around the axis (76). The first and second limit means (70), (72) define a pre determined set position relative to the holder (42).

Description

Drill Bit Setting Device

The present invention relates to drill bit setting devices.

In the sharpening of drill bits, a drill bit is presented to an abrasive medium such as a grinding wheel, and it is important that the presentation of the tip of the drill bit is correct relative to the abrasive medium. It is known to provide drill sharpening apparatus suitable for home use, which includes an abrasive medium in the form of a grinding wheel mounted for rotation within a housing, the apparatus including a holder for a drill bit which is mounted to present the drill bit correctly to the grinding wheel. Typically, the apparatus also includes a setting device to permit correct setting of the drill bit within the holder. However, typically such sharpening apparatus is used for drill bits having diameters from four millimetres up to thirteen millimetres, and the variation in diameter can cause variations in the setting of the drill bit within the holder. Such variations can result in the incorrect presentation of the drill bit to the grinding wheel.

According to a first aspect of the present invention, there is provided a drill bit setting device, the device including a holder for holding in use a drill bit substantially in alignment along a longitudinal axis of the bit, first limit means for limiting movement of the bit along the axis, and second limit means for limiting rotational movement of the bit around the axis, the first and second limit means defining a predetermined set position relative to the holder.

Possibly, the first limit means is arranged to receive a tip of the bit to align or maintain alignment of the bit along the axis.

Possibly, the device includes a setting member, which may include both the first and second limit means.

Possibly, the first limit means include a first face, against which in the set position the drill bit may abut. The first face may form at least part of an . annulus, and may slope away from the bit in use in a clockwise direction to form part of a spiral. Possibly, the first face slopes away from the bit in use in a direction inwardly towards the axis.

Possibly, the second iimit means includes a second face, which may project from the first face towards the holder.

Possibly the first limit member includes two first faces, which may be diametrically opposed.

Possibly the second limit member includes two second faces, which may be diametrically opposed.

Possibly the setting member defines an axial recess, which extends along the longitudinal axis and may extend between the first faces.

Possibly the device includes mounting means for mounting the setting member in a predetermined position relative to the holder. Possibly the mounting means include a first mounting for mounting the setting member. Possibly the first mounting member releasably mounts the setting member.

Possibly the mounting means include a second mounting for mounting the holder, and the second mounting may releasably mount the holder.

According to a second aspect of the present invention, there is provided a drill bit setting system, the system including a drill bit setting device including a holder for holding in use a drill bit and mounting means for removably mounting a setting member in a predetermined position relative to the holder, the system including a first setting member and a second setting member, the first and second setting members interchangeably mountable in the mounting means to define different predetermined set positions for different size or different type drill bits relative to the holder.

Possibly the device includes any of the features described in the preceding statements. Possibly the first and second setting members include first and second identification means respectively. Possibly the first and second identification means are different.

According to a third aspect of the present invention, there is provided drill bit sharpening apparatus, the apparatus including a drill bit setting device as described above.

According to a fourth aspect of the present invention, there is provided a setting member for a drill bit setting device as described above.

According to a fifth aspect of the present invention, there is provided a method of setting a drill bit for sharpening, the method including the steps of positioning a drill bit to be sharpened within a holder, moving the drill bit along a longitudinal axis in the holder until further movement is prevented by first limit means and rotating the drill bit around the longitudinal axis until further movement is substantially prevented by second limit means.

Possibly the method includes providing a drill bit setting device as described above.

The invention will now be described by way of example only and with reference to the accompanying drawings, in which:-

Fig. 1 is a side view of a conventional drill bit;

Fig. 2 is a perspective view of part of a sharpening apparatus in use;

Fig. 3 is a side schematic view of a drill bit setting device in use;

Fig. 4 is a side schematic view of the sharpening apparatus in use;

Fig. 5 is a perspective view of a setting block; Fig. 6 is a perspective view of part of the sharpening apparatus in a partially disassembled condition;

Figs. 7 A to 7D are perspective views of different setting blocks; and

Fig. 8 is a perspective view of another setting block.

Fig. 1 shows a conventional drill bit 10, the drill bit 10 including a shank 12, a pair of spiral flutes 14 being formed in the shank 12, and a tip 15. The tip 15 includes a pair of opposed tip faces 18, a chisel edge 16 extending between the tip faces 18. A leading edge 20 is formed between each tip face

18 and one of the flutes 14. Conventionally, drill bits are rotated clockwise into a material to form a hole, the leading edges 20 being the edges which cut into the material.

Fig. 2 shows sharpening apparatus 30 which includes a housing 32 which could be formed of a plastics material by moulding. The sharpening apparatus 30 could include a mounting 34 for mounting the housing 32 to a drive motor, and could include a cavity 36 in which in use a grinding wheel is positioned for driving by the drive motor.

The sharpening apparatus 30 includes a drill bit setting device 40. The setting device 40 includes mounting means which include a holder mounting 51 and a block mounting 63.

The setting device 40 includes a holder 42, which includes a first jaw 44 and a second jaw 46, the first jaw 44 being movable relative to the second jaw 46. A pair of threaded members 48 project upwardly from the second jaw 46 on each side of the first jaw 44 to form a clamping screw. A clamping nut 50 locates the first jaw 44 to the threaded members 48, and is arranged so that as the nut 50 rotates, the first jaw 44 is moved relative to the second jaw 46. The second jaw 46 defines a recess 56 in which a drill bit 10 is receivable, to provide longitudinal alignment of the drill bit 10. The recess 56 could be V-shaped.

The holder 42 includes mounting projections 52 which slidably engage within corresponding mounting slots 54 defined by the holder mounting 51.

As shown in Fig. 6, the setting device 40 includes a setting member in the form of a setting block 60. The setting block 60 includes a pair of mounting slots 66 which are slidably engageable with a corresponding pair of mounting projections 64 formed by the block mounting 63.

Referring to Fig. 5, the setting block 60 includes a body 61 which mounts a setting plate 62.

The setting plate 62 includes first limit means in the form of a pair of diametrically opposed first faces 70. The first faces 70 together form an annulus around a recess 74 defined by the setting plate 62. Each of the first faces 70 slopes inwardly into the plate 62 from an outer edge of the annulus to an inner edge of the annulus, and also slopes inwardly moving around the annulus in a clockwise direction to form part of a spiral.

The setting plate 62 includes second limit means in the form of a pair of diametrically opposed second faces 72 which project outwardly from the first faces 70 at their inwardmost part, each second face 72 being formed between the inwardmost part of one first face 70 and the outwardmost part of the other first face 70.

In use, the tool setting device 40 is assembled and used as follows. Referring to Fig. 6, the setting block 60 is slidably mounted to the block mounting 63, and the holder 42 is slidably mounted to the holder mounting 51. In this example, the holder mounting 51 and the block mounting 63 are integrally formed as part of the housing 32, and therefore provide a fixed, predetermined relationship between the setting block 60 and the holder 42. The holder mounting slots 54 and the block mounting projections 64 extend substantially parallel to each other.

A drill bit 10 is positioned within the recess 56 and the clamping nut 50 adjusted to bring the first jaw 44 to act upon the drill bit 10. At this stage, the first jaw 44 is positioned so that the drill bit 10 is held substantially in alignment along the longitudinal axis 76, but permitting the drill bit 10 to move along the axis 76 and to rotate around the axis 76.

A light force is applied to the drill bit 10 for example by a user gripping the drill bit shank 12 and the drill bit 10 is moved along the axis 76 as indicated by arrow A in Fig. 2 until the tip faces 18 contact the first faces 70 of the setting plate 62. In this position, the tip 15 is received between the first faces 70, the chisel edge 16 being received within the recess 74 defined by the setting plate 62. The first faces 70 thus limit movement of the bit 10 along the axis 76, and provide or maintain alignment of the bit 10 along the axis 76.

The force is maintained and the drill bit 10 is then rotated clockwise as shown by arrow B in Fig. 2. As the drill bit 10 rotates, the tip faces 18 maintain contact with and move along the first faces 70 until the leading edges 20 abut the second faces 72. The second faces 72 thus limit the rotational movement of the bit 10 around the axis 76. The drill bit 10 is now in a set position.

The application of the force is continued to maintain the drill bit 10 in the set position, and the clamping nut 50 is adjusted so that the first jaw 44 secures the drill bit 10 in the set position.

Fig. 3 shows schematically the setting device 40 in the set position, in which the bit 10 protrudes a predetermined set distance 80 from the holder 42 as set by the setting block 60. The rotational orientation of the bit 10 has also been set to a predetermined orientation in accordance with the position of the second faces 72 of the setting plate 62. The holder 42 with the bit 10 in the set position is now removed from the holder mounting 51 and can now be mounted in a sharpening position, in which the drill bit 10 is presented to a grinding wheel 82 as shown in Fig. 4, the set position ensuring that the drill bit is at the correct presentation of distance 80 and rotational orientation.

Figs. 7A to 7D show a plurality of setting blocks 60A₁ 6OB, 6OC, 6OD, each setting block 60 including a body 61 which is substantially the same in each case and a setting plate 62A, 62B, 62C, 62D respectively. Differently sized first faces 7OA, 7OB, 7OC, 7OD of different radii are formed in the setting plates 62A, 62B, 62C, 62D correspondingly, to accommodate different size drill bits, and the axial recesses 74A, 74B, 74C, 74D, are also of different radius.

Thus, for example, the setting block 6OA shown on the left hand side of the drawing has an axial recess 74A and first faces 70A of relatively small radius to accommodate drill bits of relatively small diameter, for example in the range 4.0 to 5.5mm diameter.

The setting block 6OD on the right hand side of the drawing, has an axial recess 74D and first faces 7OD of relatively large diameter, to accommodate drill bits for example of between 12 to 13mm diameter.

In each case, the first faces 70 receive the drill tip 15 to provide positive axial alignment of the tip 15. It will be noted that the centre of each of the annular first faces 70 and of the axial recess 74 progressively moves upwards as the first faces 70 and axial recess 74 increase in size, to correspond with the movement of the position of the longitudinal axis 76 of the drill bit 10 in the holder 42 as the drill bit 10 increases in size. It is important that the correct setting block 60 is used for each size drill bit 10, as otherwise the drill bit 10 will be set incorrectly for presentation to the grinding wheel 82.

The body 61 of each of the setting blocks 60 is substantially the same in each case, permitting a standard body 61 to be used with different setting B2007/003810

plates 62 thus reducing manufacturing costs. The setting plates 62 could include identification means, which could include markings and/or colours, each colour for example denoting a corresponding drill bit size range.

Fig. 8 shows a further setting block 60 which includes a body 61 of substantially the same design as previously described and a setting plate 162. The setting plate 162 includes a planar part 86 and a projecting part 84 which projects from the planar part 86. First faces 70 and second faces 72 are formed on the projecting part 84, and the projecting part 84 defines an axial recess 74, the first faces 70, the second faces 72 and the axial recess 74 being similar to those previously described.

The setting block 60 of Fig. 8 is used in a similar way to the setting blocks 60 previously described. The projecting part 84 of the setting plate 62 permits the use of drill bits of different configuration. For example, in some countries such as the U.K., standard drill bits have a 118° drill point angle. In other countries, for example the United States, standard drill bits have a 135° drill point angle. The difference in drill point angle requires a different set position for the bit 10 to ensure correct presentation to the grinding wheel 82. In the examples shown, the setting blocks shown in Figs. 1 to 7 could be suitable for drill bits having a 118° drill point angle, and the setting block of Fig. 8 could be suitable for a drill bit having a 135° drill point angle.

The provision of modular setting blocks 60 which are of a standardised size and shape to mount to the block mounting 63 permits use of the setting device 40 for a wide variety of drill bits, while providing simple and accurate setting of the drill bits to ensure correct presentation of the drill bits to the grinding wheel.

Various other modifications may be made without departing from the scope of the invention. The setting device 40 could form part of the sharpening apparatus 30 as shown in Fig. 1 , or could be provided separately. The holder and block mountings could be of any suitable design. The holder could be of any suitable design. There is thus provided a drill bit setting device, which permits a relatively unskilled person to accurately set drill bits to ensure correct presentation of the drill bits to the grinding wheel. The system is easy to use and simple to understand, and can accommodate drill bits of different sizes and designs with a minimum number of parts to ensure ease and economy of manufacture.

Whilst endeavouring in the foregoing specification to draw attention to those features of the invention believed to be of particular importance it should be understood that the Applicant claims protection in respect of any patentable feature or combination of features hereinbefore referred to and/or shown in the drawings whether or not particular emphasis has been placed thereon. _ - .

Claims

1. A drill bit setting device, the device including a holder for holding in use a drill bit substantially in alignment along a longitudinal axis of the bit, first limit means for limiting movement of the bit along the axis, and second limit means for limiting rotational movement of the bit around the axis, the first and second limit means defining a predetermined set position relative to the holder.

2. A device according to claim 1 , in which the first limit means is arranged to receive a tip of the bit to align or maintain alignment of the bit along the axis.

3. A device according to claims 1 or 2, in which the device includes a setting member.

4. A device according to claim 3, in which the setting member includes both the first and second limit means.

5. A device according to any of the preceding claims, in which the first limit means include a first face, against which in the set position the drill bit abuts.

6. A device according to claim 5, in which the first face forms at least part of an annulus.

7. A device according to claims 5 or 6, in which the first face slopes away from the bit in use in a clockwise direction to form part of a spiral.

8. A device according to any of claims 5 to 7, in which the first face slopes away from the bit in use in a direction inwardly towards the axis.

9. A device according to any of the preceding claims, in which the second limit means includes a second face.

10. A device according to claim 9 when dependent on claim 5 or any claim dependent thereon, in which the second face projects from the first face towards the holder.

11. A device according to claim 5 or any claim dependent thereon, in which the first limit means includes two first faces.

12. A device according to claim 11 , in which the two first faces are diametrically opposed.

13. A device according to claim 9 or any claim dependent thereon, in which the second limit member includes two second faces.

14. A device according to claim 13, in which the two second faces are diametrically opposed.

15. A device according to claim 3 or any claim dependent thereon, in which the setting member defines an axial recess.

16. A device according to claim 15, in which the axial recess extends along the longitudinal axis.

17. A device according to claims 15 or 16 when dependent on claim 11 or any claim dependent thereon, in which the setting member extends between the first faces.

18. A device according to claim 3 or any claim dependent thereon, in which the device includes mounting means for mounting the setting member in a predetermined position relative to the holder.

19. A device according to claim 18, in which the mounting means include a first mounting for mounting the setting member. ^

20. A device according to claim 19, in which the first mounting releasably mounts the setting member.

21. A device according to any of claims 18 to 20, in which the mounting means include a second mounting for mounting the holder.

22. A device according to claim 21 , in which the second mounting releasably mounts the holder.

23. A drill bit setting system, the system including a drill bit setting device including a holder for holding in use a drill bit and mounting means for removably mounting a setting member in a predetermined position relative to the holder, the system including a first setting member and a second setting member, the first and second setting members interchangeably mountable in the mounting means to define different predetermined set positions for different size or different type drill bits relative to the holder.

24. A system according to claim 23, in which the device is according to any of claims 1 to 22.

25. A system according to claims 23 or 24, in which the first and second setting members include first and second identification means respectively.

26. A drill bit sharpening apparatus, the apparatus including a drill bit setting device according to any of claims 1 to 22.

27. A setting member for a drill bit setting device according to any of claims 1 to 22.

28. A method of setting a drill bit for sharpening, the method including the steps of positioning a drill bit to be sharpened within a holder, moving the drill bit along a longitudinal axis in the holder until further movement is prevented by first limit means and rotating the drill bit around the longitudinal axis until further movement is substantially prevented by second limit means.

29. A method according to claim 28, in which the method includes providing a drill bit setting device according to any of claims 1 to 22.

30. A drill bit setting device substantially as hereinbefore described and with reference to Figs 2 to 8 of the accompanying drawings.

31. A drill bit setting system substantially as hereinbefore described and with reference to Figs 2 to 8 of the accompanying drawings.

32. Drill bit sharpening apparatus substantially as hereinbefore described and with reference to Figs 2 to 8 of the accompanying drawings.

33. A setting member for a drill bit setting device substantially as hereinbefore described and with reference to Figs 2 to 8 of the accompanying drawings.

34. A method of setting a drill bit for sharpening substantially as hereinbefore described and with reference to Figs 2 to 8 of the accompanying drawings.

35. Any novel subject matter or combination including novel subject matter disclosed herein, whether or not within the scope of or relating to the same invention as any of the preceding claims.