GB2479389A

GB2479389A - Hole saw assembly

Info

Publication number: GB2479389A
Application number: GB1005846A
Authority: GB
Inventors: Eupin Wang
Original assignee: Individual
Current assignee: Individual
Priority date: 2010-04-08
Filing date: 2010-04-08
Publication date: 2011-10-12
Also published as: GB201005846D0

Abstract

The assembly includes a cutting saw 30 and a drill 40. A plurality of cutting portions 33 are formed around an outer periphery of the bottom 31 of the cutting saw. Between each two neighboring cutting portions is a gap 34. Each of the cutting portions includes a cutting tooth 331 with a cusp portion 3311, a cutting edge 3312 and a supporting edge 3313. The cutting edge extends from the cusp portion to the bottom 31. The gap is located beside the cutting edge of the cutting portions. The drill includes an assembling end 41 and a working end (42, figure 3) and is inserted through an assembling hole 32 of the cutting saw. The height of the working end of the drill to the bottom of the cutting saw is larger than the height of the cutting portions. The cutting saw may have two or three cutting portions with each having either one, two or three cutting teeth. Cutting dust caused during drilling may be discharged from the gaps beside the cutting edges.

Description

HOLE SAW ASSEMBLLY

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to a saw, and more particularly to a hole saw assembly.

Description of the Prior Art

A hole saw is usually mounted on a power tool and driven by the power tool to cut a hole in wood or metal.

Referring to Fig. 1, a conventional hole saw disclosed in U.S. Patent No. 5803677 comprises a circular saw 10 and a drill 20. The circular saw 10 is provided with a bottom 11 on which is formed an annular wall 12. At the end of the annular wall 12 are formed a plurality of cutting teeth 13, and in the annular wall 12 are further defined two opposite discharging slots 14 for discharging dust. The drill 20 includes an assembling end 21 and a working end 22 and is inserted through the bottom 11 of the circular saw 10.

When the hole saw drills a hole, the drill 20 drills a central hole beforehand, and then the circular saw cuts a circular hole, at the meantime, the cutting dust is discharged from the discharging slots 14 so that the hole saw doesn't get jammed during drilling.

The present invention has arisen to mitigate and/or obviate the afore-described disadvantages.

SUMMARY OF THE INVENTION

The primary object of the present invention is to provide a hole saw assembly which utilizes the cutting portions disposed around the periphery of the bottom of the cutting saw to drill holes, and the cutting dust caused during drilling can be discharged from the gaps beside the cutting edges. Hence, the hole saw assembly of the present invention is simply structured and has a better dust discharging function.

To achieve the above object, a hole saw assembly provided by the present invention comprises: a cutting saw and a drill.

The cutting saw is provided with a bottom and an assembling hole at a center of the bottom, around an outer periphery of the bottom are formed a plurality of cutting portions, and between each two neighboring cutting portions is defined a gap, each of the cutting portions includes a cutting tooth which consists of a cusp portion, a cutting edge and a supporting edge at both sides of the cusp portion, the cutting edge extends from the cusp portion to the bottom, and the gap is located beside the cutting edge of the cutting portions; The drill has an assembling end and a working end, the drill is inserted through the assembling hole of the cutting saw and fixed therein in such a manner that the working end of the drill is oriented in the same direction as the cutting portions of the cutting saw, and a height from the working end of the drill to the bottom of the cutting saw is larger than a height of the cutting portions.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is a perspective view of a conventional hole saw; Fig. 2 is a perspective view of a hole saw assembly in accordance with a first embodiment of the present invention; Fig. 3 is a side view of the hole saw assembly in accordance with the first embodiment of the present invention; Fig. 4 is a perspective view of a hole saw assembly in accordance with a second embodiment of the present invention; Fig. 5 is a perspective view of a hole saw assembly in accordance with a third embodiment of the present invention; and Fig. 6 is a perspective view of a hole saw assembly in accordance with a fourth embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention will be clearer from the following description when viewed together with the accompanying drawings, which show, for purpose of illustrations only, the preferred embodiment in accordance with the present invention.

Referring to Figs. 2 and 3, a hole saw assembly in accordance with a first preferred embodiment of the present invention comprises a cutting saw 30 and a drill 40.

The cutting saw 30 is provided with a bottom 31 and an assembling hole 32 at the center of the bottom 31. Around the outer periphery of the bottom 31 are formed a plurality of cutting portions 33, and between each two neighboring cutting portions 33 is a gap 34. Each of the cutting portions 33 includes a cutting tooth 331 which consists of a cusp portion 3311, a cutting edge 3312 at one side of the cusp portion 3311, and a supporting edge 3313 at another side of the cusp portion 3311.

The cutting edge 3312 extends from the cusp portion 3311 to the bottom 31, and the gap 34 is located beside the cutting edge 3312 of the cutting portions 33. The cutting saw 30 of this embodiment has two cutting portions 33, and an angle between a line from the junction of the cutting edge 3312 of the first cutting portion 33 to the center of the bottom 31 and a line from the junction of the cutting edge 3312 of the second cutting portion 33 to the center of the bottom 31 is 180 degrees.

The drill 40 has one end defined as an assembling end 41 and the other end defined as a working end 42. The drill 40 is inserted through the assembling hole 32 of the cutting saw 30 and fixed therein in such a manner that the working end 42 of the drill 40 is oriented in the same direction as the cutting portions 33 of the cutting saw 30, and a height Hi from the working end 42 of the drill 40 to the bottom 31 of the cutting saw 30 is larger than a height H2 of the cutting portion 33.

The abovementioned is the structural relations of the main components of the present invention, and the operation and function of the hole saw assembly of the present invention are described as follows.

When drilling a hole in a work piece, the working end 42 of the drill 40 will drill a central positioning hole beforehand in the surface of the work piece at a location where the hole needs to be drilled so as to position the hole saw. When the central positioning hole is drilled to a certain depth at which the cusp portion 3311 of the cutting tooth 331 of each of the cutting portions 33 touches the surface of the work piece, the cutting edge 3312 of the cutting tooth 331 of each of the cutting portions 33 will start cutting. During the drilling operation, cutting dusts can be discharged from the gaps 34 which is located beside the cutting teeth 331 of the cutting portions 33, so that the cutting portions 33 don't get jammed.

Referring to Fig. 4, which shows a second embodiment of the present invention, in which, the cutting saw 30 is provided with three cutting portions 33, an angle between a line from the junction of the cutting edge 3312 of an arbitrary one of the three cutting portions 33 to the center of the bottom 31 and a line from the junction of the cutting edge 3312 of a neighboring one of the three cutting portions 33 to the center of the bottom 31 is 120 degrees.

Referring to Fig. 5, a third embodiment of the present invention is shown and is structurally and functionally similar to the second embodiment except that: each of the cutting portions 33 of this embodiment is further provided with a secondary cutting tooth 332 beside the cutting tooth 331. The secondary cutting tooth 332 is also formed with a cusp portion 3321, and a secondary cutting edge 3322 and a secondary supporting edge 3323 at both sides of the cusp portion 3321 and is located between the supporting edge 3313 of the corresponding cutting tooth 332 and the gap 34 in such a manner that the secondary cutting edge 3322 is connected to the supporting edge 3313 of its cutting tooth 332.

Referring finally to Fig. 6, a fourth embodiment of the present invention is shown and is structurally and functionally similar to the third embodiment except that: each of the cutting portions 33 of this embodiment is provided with two secondary cutting teeth 332a and 332b beside the cutting tooth 331. The secondary cutting tooth 332a is formed with a cusp portion 3321a, and a cutting edge 3322a and a supporting edge 3323a both sides of the cusp portion 3321a. The secondary cutting tooth 332a is connected to the supporting edge 3313 of the corresponding cutting tooth 331. The secondary cutting tooth 332b is also formed with a cusp portion 3321b, and a cutting edge 3322b and a supporting edge 3323b both sides of the cusp portion 332 lb. The secondary cutting edge 3322b is connected to the supporting edge 3323a of the secondary cutting tooth 332a.

The present invention utilizes the cutting portions 33 disposed around the peripheiy of the bottom 31 of the cutting saw to drill holes, and the cutting dust caused during drilling can be discharged from the gaps 34 beside the cutting edges 3312. Hence, the hole saw assembly of the present invention is simply structured and has a better dust discharging function.

While we have shown and described various embodiments in accordance with the present invention, it is clear to those skilled in the art that further embodiments may be made without departing from the scope of the present invention.

Claims

WHAT IS CLAIMED IS: 1. A hole saw assembly comprising: a cutting saw being provided with a bottom and an assembling hole at a center of the bottom, around an outer periphery of the bottom being formed a plurality of cutting portions, and between each two neighboring cutting portions being defined a gap, each of the cutting portions including a cutting tooth which consists of a cusp portion, a cutting edge and a supporting edge at both sides of the cusp portion, the cutting edge extending from the cusp portion to the bottom, and the gap being located beside the cutting edge of the cutting portions; a drill having an assembling end and a working end, the drill being inserted through the assembling hole of the cutting saw and fixed therein in such a manner that the working end of the drill is oriented in the same direction as the cutting portions of the cutting saw, and a height from the working end of the drill to the bottom of the cutting saw is larger than a height of the cutting portions.
2. The hole saw assembly as claimed in claim 1, wherein the cutting saw has two cutting portions, and an angle between a line from a junction of the cutting edge of a first cutting portion to the center of the bottom and a line from a junction of the cutting edge of a second cutting portion to the center of the bottom is 180 degrees.
3. The hole saw assembly as claimed in claim 1, wherein the cutting saw is provided with three cutting portions, an angle between a line from a junction of the cutting edge of an arbitrary of the three cutting portions to the center of the bottom and a line from a junction of the cutting edge of a neighboring one of the three cutting portions to the center of the bottom is 120 degrees.
4. The hole saw assembly as claimed in claim 1, wherein each of the cutting portions is further provided with at least one secondary cutting tooth between the supporting edge of the cutting tooth and the gap, and the secondary cutting tooth is connected to the supporting edge of the cutting tooth.
5. The hole saw assembly as claimed in claim 4, wherein each of the cutting portions is further provided with a secondary cutting tooth which is formed with a cusp portion, and a secondary cutting edge and a secondary supporting edge at both sides of the cusp portion of the secondary cutting tooth, and the secondary cutting edge is connected to the supporting edge of the cutting tooth.
6. The hole saw assembly as claimed in claim 4, wherein each of the cutting portions is provided with two secondary cutting teeth, a first one of the two secondary cutting teeth is formed with a cusp portion, and a cutting edge and a supporting edge both sides of the cusp portion, the secondary cutting tooth of the first one of the two secondary cutting teeth is connected to the supporting edge of the corresponding cutting tooth, a second one of the two secondary cutting teeth is also formed with a cusp portion, and a cutting edge and a supporting edge both sides of the cusp portion, the secondary cutting edge of the second one of the two secondary cutting teeth is connected to the supporting edge of the first one of the two secondary cutting teeth.
7. A hole saw assembly substantially as hereinbefore described with reference to and as shown in Figures 2 to 6 of the accompanying drawings.