Cutting device and adaptor for power tool

Abstract

A cutting device comprising a hexagonal shank, a tapered portion, and a cutting portion. The tapered portion has a first end and an opposing second end, the second end being closer to the cutting portion than the first end and the tapered portion has a larger cross-section at the second end than at the first end. An adaptor for a power tool, the adaptor comprising: a sleeve for receiving a shank of a cutting device, and a tool engagement portion for engaging in a chuck assembly of the power tool. An internal surface of the sleeve comprises: a hexagonal sleeve portion defining a hexagonal cavity, and a tapered surface defining a tapered cavity. The tapered cavity has a first end and an opposing second end, the second end being closer to an entry of the sleeve than the first end and the tapered cavity having a larger cross-section at the second end than at the first end. A tool assembly comprising the adaptor and the cutting device, wherein the sleeve is for receiving the hexagonal shank of the cutting device. A kit comprising the adaptor and a plurality of the cutting devices, wherein the sleeve is for receiving the hexagonal shank of each cutting device.

Description

[0001] 3556P.W0.01

[0002] 1

[0003] CUTTING DEVICE AND ADAPTOR FOR POWER TOOL

[0004] Technical Field

[0005] The present disclosure relates to cutting devices and adaptors for power tools and particularly, but not exclusively, cutting devices and adaptors for hand-held power tools, such as impact drivers and impact wrenches.

[0006] Background

[0007] Steel structures and equipment, for example bridges, require a large amount of maintenance and modifications during their lifetime. Metal modification may be carried out to increase the service life of metal structures as demand on them increases, or to meet modern compliance specifications and maintain safety. Such maintenance is usually required to be made on site, outside of workshop facilities.

[0008] When building fabricating and modifying metal or other structures, especially on site, it is often desirable to perform different operations such as the drilling of holes using a drill bit, the reaming of holes using a reamer bit, or tapping a hole using a tap bit (or operations requiring a hole cutter, holesaw, countersink, or milling cutter). To perform these tasks, a technician often needs to have not only the bits to hand, but also a power tool such as a drill, magnet drill, and impact driver / wrench. In this specification, the term power tool will refer to rotational power tools, such as drills, impact drivers, etc.

[0009] The VersaDrive® system by Holemaker Technology provides a modular cutting tool system that allows the user to quickly interchange impact-rated cutting devices. Nevertheless, further improvements in such a modular system are desired.

[0010] Summary

[0011] There is provided a cutting device comprising: a hexagonal shank, a tapered portion, and a cutting portion, wherein the tapered portion has a first end and an opposing second end, 3556P.W0.01

[0012] 2 the second end being closer to the cutting portion than the first end and the tapered portion has a larger cross-section at the second end than at the first end.

[0013] Advantageously, in use, the tapered portion locates within a tapered cavity of an adaptor, thereby locating the cutting device more accurately in the centre of the adaptor and reducing lateral movement, or wobble, of the cutting device relative to the adaptor.

[0014] In order to allow quick changing of the cutting device from an adaptor, a hexagonal shaft is usually a loose fit, which therefore allows a degree of wobble during use. The inventors have found that including the tapered portion in combination with the hexagonal shaft, significantly reduces wobble while maintaining a quickly releasable connection, thereby retaining the benefits of a hexagonal shank, while improving the location of the cutting device within the adaptor. The tapered shape also means that pressure on the cutting device during use, locates the cutting device even more accurately, thereby causing location of the cutting device to automatically be at its most accurate during high pressure use in which the location is most important.

[0015] The cutting device may be for a power tool, such as a hand-held power tool, such as an impact driver and / or impact wrench. The cutting device may be impact rated.

[0016] In this specification, the term hexagonal shank is used to describe a shank having a hexagonal cross-section. The term tapered portion refers to a portion of the cutting device which decreases in cross-sectional area along a direction of a longitudinal axis of the hexagonal shank. The longitudinal axis of the hexagonal shank runs through the centre of the hexagonal shank and may run through the centre of the tapered portion and / or cutting portion.

[0017] The cutting portion may be a drilling portion, tapping portion, saw portion, reaming portion, hole cutting portion, hole saw portion, countersinking portion, or milling cutting portion. The cutting portion is configured to contact a surface to be cut when in use. The cutting portion comprises a cutting surface. 3556P.W0.01

[0018] 3

[0019] The tapered portion may have an outer surface between the first and second ends of the tapered portion. Optionally, the outer surface is offset from a direction of the longitudinal axis of the hexagonal shank by greater than 5 degrees, optionally greater than 10 degrees and / or less than 15 degrees. The offset may alternatively be described as the slope of the outer surface measured from a direction parallel with the longitudinal axis of the hexagonal shank. The taper shape of the tapered portion allows relatively large manufacturing tolerances while still achieving precise lateral location of the cutting device. The inventors have found that these slopes of the outer surface of the tapered portion allow quick disconnection of the tapered portion in a corresponding adaptor cavity without locking, so the connection between the cutting device and adaptor in use remains quickly releasable.

[0020] The outer surface of the tapered portion may have a conical frustrum shape. The outer surface of the tapered portion may be centred on the longitudinal axis of the hexagonal shank. The first and second ends of the tapered portion may be circular.

[0021] Optionally, the tapered portion is between the hexagonal shank and the cutting portion. In this way, the tapered portion decreases in cross-sectional area from its end second end which is closest to the cutting portion, to its first end which is closest to the hexagonal shank.

[0022] Optionally, the cutting device comprises high-speed steel (HSS), for example, HSS-M2. Optionally, the cutting device is formed as one-piece. The cutting portion, tapered portion and hexagonal shank are formed integrally with one another.

[0023] Optionally, the tapered portion has a length between the first and second end along a direction parallel with the longitudinal axis of the hexagonal shank of between less than 8mm, optionally, less than 7mm, optionally 6mm. Optionally the length of the tapered portion is greater than 4 or 5mm. By using a short tapered portion, the connection between the cutting device and adaptor in use remains quickly releasable.

[0024] Optionally, the tapered portion has a width measured at the second end perpendicularly to the longitudinal axis of the hexagonal shank, the width being between 10mm and 20mm, 3556P.W0.01

[0025] 4 optionally between 13 and 16mm, optionally between 14 and 15mm, optionally 14.6 to 14.7. The width may refer to a diameter of the second end of the tapered portion.

[0026] Optionally, the hexagonal shank has a length measured parallel to the longitudinal axis of the hexagonal shank, the length being less than 28mm, and / or greater than 14mm. Optionally, the length is between 20 and 25, optionally 23.5mm. Such lengths of the hexagonal shank allow stable connecting of the shank in the adaptor.

[0027] Optionally, the hexagonal shank has a recess in a side surface of the hexagonal shank. Optionally, the recess has a flat base and / or is suitable for receiving a fastening such as a screw and / or ball-bearing. Optionally the hexagonal shank has a plurality, such as three, such recesses. Optionally, the plurality of recesses are on a common plane transverse the shank and / or are spaced equally about said shank. A recess diameter may be between 4 to 5.5mm. A recess depth may be between 1 and 2 mm, for example, 1.5mm.

[0028] Optionally, the cutting device is one of a drill bit, a reamer, a tap, a hole cutter, a hole saw, a countersink, or a milling cutter.

[0029] There is further provided an adaptor for a power tool, the adaptor comprising: a sleeve for receiving a shank of a cutting device, and a tool engagement portion for engaging in a chuck assembly of the power tool, wherein an internal surface of the sleeve comprises: a hexagonal sleeve portion defining a hexagonal cavity, and a tapered surface defining a tapered cavity; wherein the tapered cavity has a first end and an opposing second end, the second end being closer to an entry of the sleeve than the first end and the tapered cavity having a larger cross-section at the second end than at the first end.

[0030] The hexagonal sleeve portion defines a hexagonal cross-section cavity. The inner surface of the hexagonal sleeve portion has an open-ended hexagonal prism shape. Optionally, the second end of the tapered cavity forms the entry of the sleeve. 3556P.W0.01

[0031] 5

[0032] The tapered surface may have a conical frustrum shape. The tapered surface may be centred on a longitudinal axis of the hexagonal cavity. The first and second ends of the tapered cavity may be circular.

[0033] The longitudinal axis of the hexagonal cavity runs through the centre of the hexagonal cavity and may run through the centre of the tapered cavity and / or tool engagement portion.

[0034] The adaptor may be for a hand-held power tool, such as an impact driver and / or impact wrench. The adaptor may be impact rated.

[0035] Optionally, the tapered surface is offset from a direction of the longitudinal axis of the hexagonal cavity by greater than 5 degrees. In other words, the slope of the tapered surface is 5 degrees, measured from a direction parallel with the longitudinal axis of the hexagonal cavity. Optionally, the offset or slope may be greater than 10 degrees, and / or less than 15 degrees.

[0036] Optionally, the tapered surface is between the hexagonal sleeve portion and the entry to the sleeve.

[0037] Optionally, the adaptor comprises nitriding steel, for example 722M24. The nitriding steel may be heat treated, for example for 72hr.

[0038] Optionally, the tapered cavity defined by the tapered surface has a length between the first and second end along a direction parallel with a longitudinal axis of the hexagonal cavity of between 4 and 8mm, optionally between 5 and 7mm, optionally 6mm.

[0039] Optionally, the tapered cavity has a width measured at the second end perpendicularly to a longitudinal axis of the hexagonal cavity, the width being between 10mm and 20mm, optionally between 13 and 16mm, optionally between 14 and 15mm, optionally between 14.6mm and 14.7mm. The width may refer to a diameter of the second end of the tapered cavity. 3556P.W0.01

[0040] 6

[0041] Optionally, the hexagonal cavity has a length measured parallel to a longitudinal axis of the hexagonal cavity, the length being less than 28mm, optionally less than 25 and / or greater than 14mm or 20mm. Optionally the length is 23.5mm.

[0042] Optionally, adaptor further comprising one or more fasteners for engaging the shank within the sleeve. Optionally the fastener is a screw or ball-bearing. Optionally, the adaptor comprises a plurality, such as three such fasteners. Optionally, the fasteners are on a common plane transverse the longitudinal axis and optionally spaced equally about said hexagonal cavity. Optionally a maximum diameter from an outer surface of the hexagonal sleeve portion to an outer edge of one of the ball fasteners is less than 19mm.

[0043] Optionally, the sleeve is for receiving the hexagonal shank of a cutting device as described above.

[0044] There is further provided a tool assembly comprising an adaptor as described above and a cutting device as described above.

[0045] The shape and size of the tapered cavity of the adaptor may match the shape and size of the tapered portion of the cutting device. Optionally with a tolerance of less than 0.15mm, for example 0.1mm, for distances of less than 30mm.

[0046] There is further provided a kit comprising an adaptor as described above and a plurality of cutting devices as described above.

[0047] The cutting devices, adaptors, tool assemblies and kits described above may be combined in any possible combination. The optional features described above are equally applicable to all of the described cutting devices, adaptors, tool assemblies and kits and are not limited to the particular cutting device / adaptor / tool assembly / kit with which they are described here. The essential features of any of the cutting devices / adaptors / tool assemblies / kits described may be optional features of any other cutting device / adaptor / tool assembly / kit described. 3556P.W0.01

[0048] 7

[0049] Further features and advantages of the above-described aspects of the present disclosure will become apparent from the claims and the following description.

[0050] Brief Description of Drawings

[0051] Embodiments of the present disclosure will now be described by way of example only, with reference to the following diagrams, in which: -

[0052] Fig. 1A is a side view of a portion of a cutting device;

[0053] Fig. IB is a perspective view of the cutting device of Fig. 1A;

[0054] Fig 2A is a side view of a portion of another cutting device;

[0055] Fig. 2B is a perspective view of the cutting device of Fig. 2A;

[0056] Fig. 3A is a longitudinal section view of an adaptor;

[0057] Fig. 3B is a close-up view of a portion of the view shown in Fig. 3A;

[0058] Fig. 4 is a longitudinal section view of a tool assembly including the adaptor of Fig. 3A having the portion of the cutting device of Fig. 1A therein.

[0059] Detailed Description

[0060] A number of different embodiments of the disclosure are described subsequently. In order to minimise repetition, similar features of the different embodiments are numbered with a common two-digit reference numeral and are differentiated by a third digit placed before the two common digits. Such features are structured similarly, operate similarly, and / or have similar functions unless otherwise indicated.

[0061] Figs. 1A and IB shows a cutting device 100 comprising: a hexagonal shank 101, a tapered portion 102, and a stem 103 of a cutting portion. The remaining part of the cutting portion including a cutting surface is not shown, but would extend to the right as shown in Fig. 1A from the stem 103. The tapered portion 102 has a first end 102a and an opposing second end 102b, the second end being closer to the cutting portion than the first end. The tapered portion 102 has a larger cross-section at the second end 102b than at the first end 102a. 3556P.W0.01

[0062] 8

[0063] The cutting device 100 is impact-rated and therefore suitable for use with an impact driver and / or impact wrench.

[0064] Hexagonal shank 101 has a hexagonal cross-section. The longitudinal axis Al of the hexagonal shank 101 runs through the centre of the hexagonal shank.

[0065] The tapered portion 102 is a portion of the cutting device which decreases in cross- sectional area along the direction of the longitudinal axis Al of the hexagonal shank. The longitudinal axis Al of the hexagonal shank also runs through the centre of the tapered portion.

[0066] The tapered portion 102 has an outer surface between the first and second ends 102a, 102b. The outer surface is offset from a direction of the longitudinal axis of the hexagonal shank by 5 degrees, though in other embodiments the offset may be greater than 10 degrees. The offset is the slope of the outer surface measured from a direction parallel with the longitudinal axis Al of the hexagonal shank. The outer surface of the tapered portion 102 has a conical frustrum shape centred on the longitudinal axis Al of the hexagonal shank

[0067] 102. The first and second ends 102a, 102b are circular.

[0068] The tapered portion 102 is between the hexagonal shank 101 and the cutting portion stem

[0069] 103.

[0070] The tapered portion 102 has a length between the first and second end 102a, 102b along a direction parallel with the longitudinal axis Al of the hexagonal shank of 6mm. The tapered portion 102 has a diameter measured at the second end 102b perpendicularly to the longitudinal axis Al of the hexagonal shank, the diameter being between 14.6 to 14.7mm.

[0071] The hexagonal shank 101, tapered portion 102 and stem of the cutting portion 103 are formed integrally with one-another, of one piece of HSS, for example, HSS-M2. 3556P.W0.01

[0072] 9

[0073] The hexagonal shank 101 has a length measured parallel to the longitudinal axis Al of the hexagonal shank, the length being 23.5mm. The hexagonal shank 101 has three recesses 104 in a side surface of the hexagonal shank 101. The recesses have flat bases and are suitable for receiving a fastening such as a screw and / or ball-bearing. The plurality of recesses are on a common plane transverse the shank 101 and are spaced equally about said shank. The diameter of each recess is between 4 and 5.5mm. A recess depth for each recess is 1.5mm.

[0074] Figs. 2A and 2B show a cutting device 200 comprising: a hexagonal shank 201, a tapered portion 202, and a stem 203 of a cutting portion. The remaining part of the cutting portion including a cutting surface is not shown, but would extend to the right as shown in Fig. 2 A from the stem 203. The tapered portion 202 has a first end 202a and an opposing second end 202b, the second end being closer to the cutting portion than the first end. The tapered portion 202 has a larger cross-section at the second end 202b than at the first end 202a. The longitudinal axis A2 of the hexagonal shank 201 runs through the centre of the hexagonal shank 201, tapered portion 202 and cutting portion stem 203.

[0075] The cutting device 200 is similar to the cutting device 100 in Fig. 1A and IB, except that the width / diameter of the cutting portion stem 203 is smaller than the width / diameter of the stem 103 of cutting device 100. The smaller stem 203 allows for connection / formation of smaller cutting portions and the larger stem 103 for the connection / formation of larger cutting portions, for example tools for cutting larger holes.

[0076] The remaining features and dimensions of the cutting device 200 are the same as described above for cutting device 100 and corresponding features between the two devices are labelled with common second and third digits.

[0077] Fig. 3A shows an adaptor 300 for a power tool. The adaptor 300 comprises a sleeve 301 for receiving shank 101, 102 of cutting device 100, 200, and a tool engagement portion 302 for engaging in a chuck assembly of the power tool. An internal surface of the sleeve comprises: a hexagonal sleeve portion 303 defining a hexagonal cavity, and a tapered surface 304 defining a tapered cavity. The tapered cavity has a first end 304a and an opposing second 3556P.W0.01

[0078] 10 end 304b, the second end being closer to an entry 305 of the sleeve than the first end and the tapered cavity having a larger cross-section at the second end than at the first end.

[0079] The second end 304b of the tapered cavity forms the entry 305 of the sleeve and the tapered surface 304 is between the hexagonal sleeve portion and the entry to the sleeve.

[0080] The tapered surface 304 has a conical frustrum shape and is centred on a longitudinal axis A3 of the hexagonal cavity. The first 304a and second 304b ends of the tapered cavity are circular.

[0081] A close up of circle B in Fig. 3A is shown in Fig. 3B and shows that the tapered surface 304 is offset from the angle of the surface of the hexagonal cavity 303 by 5 degrees. As the hexagonal cavity is a hexagonal prism centred on the axis A3, the direction of the surface

[0082] 303 in this cross-sectional view is the same as the direction of the axis A3, so Fig. 3B shows that the offset of the tapered surface 304 is also 5 degrees from a direction of the longitudinal axis A3 of the hexagonal cavity. In other words, the slope of the tapered surface

[0083] 304 is 5 degrees, measured from a direction parallel with the longitudinal axis A3 of the hexagonal cavity. In other embodiments, the offset or slope may be greater than 10 degrees, and / or less than 15 degrees.

[0084] The tapered cavity defined by the tapered surface 304 has a length between the first 304a and second 304b end along a direction parallel with a longitudinal axis A3 of the hexagonal cavity of 6mm.

[0085] The tapered cavity has a diameter measured at the second end 304b perpendicularly to the longitudinal axis A3 of the hexagonal cavity, the diameter being between 14.6mm and 14.7mm.

[0086] The hexagonal sleeve portion 301 defines a hexagonal cross-section cavity. The inner surface of the hexagonal sleeve portion 303 has an open-ended hexagonal prism shape. The longitudinal axis A3 of the hexagonal cavity runs through the centre of the hexagonal cavity, through the centre of the tapered cavity and through the tool engagement portion. 3556P.W0.01

[0087] 11

[0088] The hexagonal cavity has a length measured parallel to the longitudinal axis A3 of the hexagonal cavity, the length being 23.5mm.

[0089] The adaptor further comprises three fasteners 306 for engaging the shank 101, 201 within the sleeve 301. The fasteners 306 are ball-bearings and are on a common plane transverse the longitudinal axis A3 and are spaced equally about said hexagonal cavity. A maximum diameter from an outer surface of the hexagonal sleeve portion to an outer edge of one of the ball fasteners, crossing the axis A3 is less than 19mm.

[0090] The adaptor is for a hand-held power tool, such as an impact driver and / or impact wrench and is impact rated. The adaptor is formed of 722M24 nitriding steel, heat treated for 72hr.

[0091] Fig. 4 shows a tool assembly comprising the adaptor 300 as described above and cutting device 100 as described above.

[0092] The shape and size of the tapered cavity of the adaptor 300 matches the shape and size of the tapered portion 102 of the cutting device 100 with a tolerance of 0.1mm, for distances of less than 30mm.

[0093] In Fig. 1A, IB, 2A, 2B and 4, the cutting portion is not specified as only the stem is shown. The cutting portion may be a drilling portion, tapping portion, saw portion, reaming portion, hole cutting portion, hole saw portion, countersinking portion, or milling cutting portion. The longitudinal axis Al, A2 of the hexagonal shank also runs through the centre of the cutting portion. The remaining part of the cutting portion (not shown) including the cutting surface may also be formed of HSS within said one-piece, or may be formed of other materials and attached at the stem, depending on the purpose of the cutting portion.

[0094] So, the cutting devices shown in Fig. 1A, IB, 2A, 2B and 4 are each one of a drill bit, a reamer, a tap, a hole cutter, a hole saw, a countersink, or a milling cutter.

[0095] Although particular embodiments of the disclosure have been disclosed herein in detail, this has been done by way of example and for the purposes of illustration only. The 3556P.W0.01

[0096] 12 aforementioned embodiments are not intended to be limiting with respect to the scope of the appended claims.

[0097] It is contemplated by the inventors that various substitutions, alterations, and modifications may be made to the invention without departing from the scope of the invention as defined by the claims.

Claims

3556P.W0.0113CLAIMS1. A tool assembly comprising: a cutting device comprising a hexagonal shank, a tapered portion, and a cutting portion, wherein the tapered portion is between the hexagonal shank and the cutting portion; and an adaptor for a power tool, the adaptor comprising: a sleeve for receiving the cutting device, an internal surface of the sleeve comprising a hexagonal sleeve portion defining a hexagonal cavity for receiving the hexagonal shank, and a tapered surface defining a tapered cavity for receiving the tapered portion, and a tool engagement portion for engaging in a chuck assembly of the power tool; wherein the tapered portion has a first end and an opposing second end, the second end being closer to the cutting portion than the first end and the tapered portion has a larger cross-section at the second end than at the first end, and the tapered cavity has a first end and an opposing second end, the second end being closer to an entry of the sleeve than the first end and the tapered cavity having a larger cross-section at the second end than at the first end.

2. A tool assembly according to claim 1, wherein the tapered portion has an outer surface between the first and second ends of the tapered portion, the outer surface being offset from a direction of a longitudinal axis of the hexagonal shank by greater than 5 degrees.

3. A tool assembly according to any preceding claim, wherein the cutting device comprises high-speed steel.

4. A tool assembly according to any preceding claim, wherein the tapered portion has a length between the first and second end along a direction parallel with a longitudinal axis of the hexagonal shank of between 4 and 8mm.3556P.W0.01145. A tool assembly according to any preceding claim, wherein the tapered portion has a width measured at the second end perpendicularly to a longitudinal axis of the hexagonal shank, the width being between 10mm and 20mm.

6. A tool assembly according to any preceding claim, wherein the hexagonal shank has a length measured parallel to a longitudinal axis of the hexagonal shank, the length being less than 28mm.

7. A tool assembly according to any preceding claim, wherein the hexagonal shank has a recess in a side surface of the hexagonal shank.

8. A tool assembly according to any preceding claim, wherein the cutting device is one of a drill bit, a reamer, a tap, a hole cutter, a hole saw, a countersink, or a milling cutter.

9. A tool assembly according to any preceding claim, wherein the tapered surface is offset from a direction of a longitudinal axis of the hexagonal cavity by greater than 5 degrees.

10. A tool assembly according to any preceding claim, wherein the tapered surface is between the hexagonal sleeve portion and the entry to the sleeve.

11. A tool assembly according to any preceding claim, wherein the adaptor comprises nitriding steel.

12. A tool assembly according to any preceding claim, wherein the tapered surface has a length between the first and second end along a direction parallel with a longitudinal axis of the hexagonal cavity of between 4 and 8mm13. A tool assembly according to any preceding claim, wherein the tapered cavity has a width measured at the second end perpendicularly to a longitudinal axis of the hexagonal cavity, the width being between 10mm and 20mm.3556P.W0.011514. A tool assembly according to any preceding claim, wherein the hexagonal cavity has a length measured parallel to a longitudinal axis of the hexagonal cavity, the length being less than 28mm.

15. A tool assembly according to any of any preceding claim, the adaptor further comprising one or more fasteners for engaging the shank within the sleeve.

16. A kit comprising a tool assembly according to any preceding claim and one or more additional cutting devices, each additional cutting device comprising: a hexagonal shank; a tapered portion; and a cutting portion; wherein the tapered portion has a first end and an opposing second end, the second end being closer to the cutting portion than the first end and the tapered portion has a larger cross-section at the second end than at the first end.

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