CA2540096A1

CA2540096A1 - Hammer drill bit chuck attachment

Info

Publication number: CA2540096A1
Application number: CA 2540096
Authority: CA
Inventors: Fern Beauchamp; Gerard Grand
Original assignee: Dragonfire Group Holdings Ltd
Current assignee: Dragonfire Group Holdings Ltd
Priority date: 2006-03-03
Filing date: 2006-03-03
Publication date: 2007-09-03

Abstract

A hammer drill bit chuck attachment for use with a conventional electric drill comprises a main shaft for secure engagement in the chuck of the drill. An actuator mechanism is mounted in freely rotatable relation on the main shaft. An impact--receiving member is connected to the main shaft for rotation therewith about the longitudinal axis and for longitudinal sliding movement substantially along the longitudinal axis between an operatively engaged position whereat the actuator mechanism engages the impact-receiving member as the main shaft rotates with respect to the actuator mechanism, to thereby impart reciprocating motion along the longitudinal axis to the impact-receiving member, and a disengaged position whereat the actuator mechanism is removed from the engagement with the impact-receiving member. A rotation--precluding link is operatively connectable between the actuator mechanism and a conventional electric drill for substantially precluding rotation of the actuator mechanism on the main shaft.

Description

FIELD OF THE INVENTION

[0001] The present invention relates to hammer drills, and more particularly to hammer drill bit chuck attachments.

BACKGROUND OF THE INVENTION

[0002] Hammer drills are well known and are typically used, even by home craftsmen, to drill holes in relatively hard substances, such as concrete and the like. Such hammer drills typically have a rotating spindle that drives the drill chuck. A fixed disc having a rearwardly facing toothed surface is secured to the rotations spindle. A movable disc having a forwardly facing toothed surface is selectively engageable with the rearwardly facing toothed surface of the fixed disc so as to provide the hammer drill function. Although the apparatus does work, it presents a serious drawback in that the impact created by the engagement of the two toothed surfaces is directed forwardly through the drill bit and also back through the drill itself, as a reaction force. Accordingly, the bearings of the drill tend to wear excessively, which is highly undesirable. Further, it is well known that there can be significant heat build with prior art hammer drills.

[0003] Such hammer drills, also known as percussion drills, can be found in for example United States Patent 2,942,852, issued June 28, 1960 to Muthman and United States Patent 5,653,294, issued August 5, 1997 to Thurler.

[0004] United States Patent 4,450,919, issued May 29, 1984 to Cousineau discloses a drill attachment for use with a conventional electric drill. This drill attachment provides a hammering and drilling action so that a conventional drill may be used to drill into hard substances. The drill attachment comprises a hammer assembly having a rearward case and a forward chuck assembly. A
rotating spindle is mounted within the case and has a reciprocating spindle mounted in the front end thereof. The rotating spindle drives a drill chuck within the chuck assembly via the reciprocating spindle. A rotating clutch plate mounted on the reciprocating spindle rotates with the reciprocating spindle.
Teeth on the rotating clutch plate engage cooperating teeth on the stationary clutch that is securely mounted on the case. A
removable handle connected to the case permits the case, and therefore the stationary clutch, to be selectively moved forwardly such that the teeth of the stationary clutch engage the teeth of the rotating clutch plate, to thereby impart the hammering function to a drill bit retained within the bit chuck. As is well known, the friction generated by the two sets of co-operating teeth frictionally engaging each other, is inefficient in terms of energy transfer and causes unnecessary heat buildup.

[0005] Another known prior art hammer drill attachment for use with conventional drills comprises a main shaft rotatable by a conventional drill and having an impact-receiving member thereon.
An actuator mechanism is mounted in freely rotatable relation and in slidable relation along the main shaft for actuating engagement with the impact-receiving member. A handle is connected to the actuator mechanism for ready manipulation of the actuator mechanism into engagement with the impact-receiving member. Although this device works well, one problem with it is that two hands are required to operate it in use on a conventional drill. One hand is used to hold and manipulate the drill and one hand is used to manipulate the handle of the hammer drill attachment, which is inconvenient. Further, sometimes it is necessary to use one hand to hold a workpiece that is being worked on, which therefore cannot be done using this prior art device.

[0006] It is a further object of the present invention to provide a hammer drill bit chuck attachment.

[0007] It is yet a further object of the present invention to provide a hammer drill bit chuck attachment that is inexpensive to manufacture.

[0008] It is yet a further object of the present invention to provide a hammer drill bit chuck attachment that is robust.

[0009] It is yet a further object of the present invention to provide a hammer drill bit chuck attachment wherein heat build up is minimized.

[00010] It is yet a further object of the present invention to provide a hammer drill bit chuck attachment wherein an electric drill used in conjunction with the hammer drill bit chuck attachment can be operated at lower rotational speeds.

[00011] It is yet a further object of the present invention to provide a hammer drill bit chuck attachment that is operable without direct manual actuation in an operatively engaged position.

[00012] It is yet a further object of the present invention to provide a hammer drill bit chuck attachment wherein more power is available to be transferred to a drill bit from an electric drill used in conjunction with the hammer drill bit chuck attachment.

SUbIlKARY OF THE INVENTION

[00013] In accordance with one aspect of the present invention there is disclosed a novel hammer drill bit chuck attachment for use with a conventional electric drill. The hammer drill bit chuck attachment comprises a main shaft for secure engagement in the chuck of a conventional electric drill and defining a longitudinal axis. An actuator mechanism is mounted in freely rotatable relation on the main shaft. An impact-receiving member is connected to the main shaft for rotation therewith about the longitudinal axis and for longitudinal sliding movement substantially along the longitudinal axis between an operatively engaged position whereat the actuator mechanism engages the impact-receiving member as the main shaft rotates with respect to the actuator mechanism, to thereby impart reciprocating motion along the longitudinal axis to the impact-receiving member, and a disengaged position whereat the actuator mechanism is removed from the engagement with the impact-receiving member. A rotation-precluding link is operatively connectable between the actuator mechanism and a conventional electric drill for substantially precluding rotation of the actuator mechanism on the main shaft.

[00014] In accordance with another aspect of the present invention there is disclosed a novel biasing apparatus for use with hammer drill bit chuck attachment. The biasing apparatus comprises an actuator engaging portion, a drill engaging portion, and a resilient biasing portion extending between the actuator engaging portion and the drill engaging portion to bias the actuator engaging portion against an actuator mechanism of a hammer drill bit chuck attachment.

[00015] Other advantages, features and characteristics of the present invention, as well as methods of operation and functions of the related elements of the structure, and the combination of parts and economies of manufacture, will become more apparent upon consideration of the following detailed description and the appended claims with reference to the accompanying drawings, the latter of which is briefly described herein below.

BRIEF DESCRIPTION OF THE DRAWINGS

[00016] The novel features which are believed to be characteristic of the hammer drill bit chuck attachment according to the present invention, as to its structure, organization, use and method of operation, together with further objectives and advantages thereof, will be better understood from the following drawings in which a presently preferred embodiment of the invention will now be illustrated by way of example. It is expressly understood, however, that the drawings are for the purpose of illustration and description only, and are not intended as a definition of the limits of the invention. In the accompanying drawings:

[00017] Figure 1 is a perspective view from the back of the preferred embodiment of the hammer drill bit chuck attachment according to the present invention, secured to a drill chuck;

[00018] Figure 2 is a perspective view from the front of the preferred embodiment hammer drill bit chuck attachment and drill chuck of Figure 1;

[00019] Figure 3 is a perspective view from the back of the preferred embodiment hammer drill bit chuck attachment of Figure 1, but with the drill chuck removed;

[00020] Figure 4 is a perspective view from the front of the preferred embodiment hammer drill bit chuck attachment of Figure 3;

[00021] Figure 5 is a side elevational view of the preferred embodiment hammer drill bit chuck attachment of Figure 3; and [00022] Figure 6 is a side elevational view of the preferred embodiment hammer drill bit chuck attachment of Figure 3, taken along section line 6-6 of Figure 3;

[00023] Figure 7 is a side elevational view of the preferred embodiment hammer drill bit chuck attachment of Figure 3, taken along section line 7-7 of Figure 6;

[00024] Figure 8 is a front end view of the preferred embodiment hammer drill bit chuck attachment of Figure 3;

[00025] Figure 9 is a back end view of the preferred embodiment hammer drill bit chuck attachment of Figure 3;

[00026] Figure 10 is an exploded perspective view from the back of the preferred embodiment hammer drill bit chuck attachment and drill chuck of Figure 1;

[00027] Figure 11A is a perspective view from the front of the rotation-precluding link of the preferred embodiment hammer drill bit chuck attachment of Figure 1;

[00028] Figure 11B is a side elevational view of the rotation-precluding link of Figure 11A;

[00029] Figure 11C is a top plan view of the rotation-precluding link of Figure 11A;

[00030] Figure 11D is a front end elevational view of the rotation-precluding link of Figure 11A;

[00031] Figure 11E is a back end elevational view of the rotation-precluding link of Figure 11A;

[00032] Figure 11F is a sectional side elevational view of the rotation-precluding link of Figure 11A, taken along section line 11F-11F of Figure 11E;

[00033] Figure 12A is a perspective view from the back of the impact-receiving member of the preferred embodiment hammer drill bit chuck attachment of Figure 1;

[00034] Figure 12B is a back end elevational view of the impact-receiving member of Figure 12A;

[00035] Figure 12C is a side elevational view of the impact-receiving member of Figure 12A;

[00036] Figure 12D is a sectional side elevational view of the impact-receiving member of Figure 12A, taken along section line 12D-12D of Figure 12C;

[00037] Figure 13A is a perspective view from the front of the main body of the actuator member of the preferred embodiment hammer drill bit chuck attachment of Figure 1;

[00038] Figure 13B is a side elevational view of the main body of the actuator member of Figure 13A;

[00039] Figure 13C is a front end elevational view of the main body of the actuator member of Figure 13A;

[00040] Figure 13D is a back end elevational view of the main body of the actuator member of Figure 13A;

[00041] Figure 13E is a sectional side elevational view of the main body of the actuator member of Figure 13A, taken along section line 13E-13E of Figure 13D;

[00042] Figure 13F is a sectional side elevational view of the main body of the actuator member of Figure 13A, taken along section line 13F-13F of Figure 13B;

[00043] Figure 14A is a perspective view from the front of the main shaft of the preferred embodiment hammer drill bit chuck attachment of Figure 1;

[00044] Figure 14B is a side elevational view of the main shaft of Figure 14A;

[00045] Figure 14C is a front end elevational view of the main shaft of Figure 14A;

[00046] Figure 14D is a back end elevational view of the main shaft of Figure 14A;

[00047] Figure 14E is a sectional side elevational view of the main shaft of Figure 14A, taken along section line 14E-14E of Figure 14D;

[00048] Figure 15A is a perspective view from the front of the secondary shaft of the preferred embodiment hammer drill bit chuck attachment of Figure 1;

[00049] Figure 15B is a side elevational view of the secondary shaft of Figure 15A;

[00050] Figure 15C is a back end elevational view of the secondary shaft of Figure 15A;

[00051] Figure 15D is a front end elevational view of the secondary shaft of Figure 15A;

[00052] Figure 15E is a sectional side elevational view of the secondary shaft of Figure 15A, taken along section line 15E-15E of Figure 15D;

[00053] Figure 16 is a side elevational view from the front of the preferred embodiment hammer drill bit chuck attachment and drill chuck of Figure 1, with the impact-receiving member in its operatively engaged position; and, [00054] Figure 17 is a side elevational view from the front of the preferred embodiment hammer drill bit chuck attachment and drill chuck of Figure 1, with the impact-receiving member in its disengaged position.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[00055] Reference will now be made to Figures 1 through 17, which show a preferred embodiment of the hammer drill bit chuck attachment of the present invention, as indicated by general reference numeral 20, for use with a conventional electric drill.
The hammer drill bit chuck attachment 20 comprises a substantially hollow main shaft 30 for secure engagement in the chuck of a conventional electrical drill (not shown) and having a forward spindle portion 33 and a rearward drill engaging portion 34. A
stop flange 31 is disposed between the forward spindle portion 33 and the rearward drill engaging portion 34. The main shaft 30 defines a longitudinal axis "L" about which the main shaft 30 rotates. A secondary shaft 80 defines a longitudinal axis "LS"
that is axially aligned with the longitudinal axis "L" of the main shaft 30. The secondary shaft 80 comprises a threaded front portion 82, and a rear main-shaft-engaging portion 84. A stop flange 86 is disposed between the threaded front portion 82 and the rear main-shaft-engaging portion 84.

[00056] A conventional drill bit chuck 35 is mountable on the threaded front portion 82 of the secondary shaft 80 for rotation therewith, and comprises three movable jaw members 36 that receive and retain a conventional drill bit 29 therein. The drill bit chuck 35 has a threaded bore hole 39a that receives the co-operating threaded front portion 82 of the secondary shaft 80 in secure engagement.

[00057] An impact-receiving member 40 is connected to the main shaft 30 for rotation therewith about the longitudinal axis "L", and for longitudinal sliding movement substantially along the longitudinal axis "L", as will be discussed in greater detail subsequently and projects radially outwardly from the secondary shaft 80 for longitudinal and rotational movement therewith. The impact-receiving member 40 comprises a main body portion 42 and a rearward ring member 45 and has a threaded central aperture 41 to permit mounting of the impact member 40 on the secondary shaft 80.
The rearward ring member 45 maybe set permanently in place by means of press-fitting or screw-fitting, or both, or may be removable and replaceable so as to allow an end user to select the frequency and amplitude of impacts, as desired.

[00058] The rearward ring member 45 has a plurality of impact portions 46. As can readily be seen in the figures, the plurality of impact portions 46 are rearwardly facing and comprise a plurality of ramp portions. Alternatively, other configurations of impact portions could be used, such as small metal cylinder disposed in rotatable relation within the rearward ring member 45.

[00059] In the preferred embodiment, as illustrated, there are twelve impact portions 46 that are substantially evenly spaced around the rearwardly facing impact portions 46. Alternatively, there can be any suitable number of impact portions 46. Also alternatively, the impact portions 46 may be irregularly spaced, or spaced apart in any other suitable manner. Alternatively, it is also contemplated that the plurality of impact portions 46 could include a plurality of indentations (not specifically shown).

[00060] The impact receiving member 40 is also connected to the main shaft 30, as aforesaid, for longitudinal sliding movement substantially along the longitudinal axis " L" between an operatively engaged position, as can be best seen in Figure 16, and this engaged position as can be best seen in Figure 17, as will be discussed in greater detail subsequently.

[00061] The impact receiving member 40 is connected to the main shaft 30 for rotation therewith about the longitudinal axis "L" by means of the secondary shaft 80. More specifically, the rear main-shaft-engaging portion 84 of the secondary shaft 80 is polygonal in cross-section, and more specifically hexagonal in cross-section, and fits in sliding relation within a co-operating hexagonal-shaped aperture 33a in the front end of the forward spindle portion 33 of the main shaft 30. The secondary shaft 80 is retained in place by means of a threaded fastener 88 that engages a co-operating bore hole 87 in the back end of the rear main-shaft-engaging portion 84.
The head 89 of the threaded fastener 88 abuts against an annular shoulder 33b at the back end of the co-operating hexagonal aperture 33a.

[00062] An actuator mechanism 50 is mounted in freely rotatable relation on the main shaft 30 and comprises a main body member 52 having a throughpassage 54. The actuator mechanism 50 is mounted in freely rotatable relation and in freely slidable relation, with the forward spindle portion 33 of the main shaft 30 disposed within the throughpassage 54. In this manner, the actuator mechanism 50 is slidably engaged on the forward spindle portion 33 of the main shaft 30 for movement along the longitudinal axis "L" on the main shaft 30 rearwardly of the impact-receiving member 40, for longitudinal sliding movement along the drive shaft 30 between a forward operatively engaged position, as is best seen in Figure 16, and a rearward disengaged position, as is best seen in Figure 17.

[00063] At least one roller member is rotationally mounted, and in the preferred embodiment as illustrated, three roller members 60 are rotationally mounted on the main body member 52 of the actuator mechanism 50 by means of threaded fasteners 61 threadibly engaged in co-operating threaded apertures 53 in the main body member 52.
The axis of rotation "R" of each roller member 60 is substantially perpendicular to the longitudinal axis "L" of the main shaft 30.
The roller members 60, as illustrated, are bearing assemblies having an outer ring freely rotatably mounted onto an inner hub.
Other suitable designs of roller members 60 could also be used.

[00064] In the operatively engaged position of the impact-receiving member, the roller members 60 engage the rearwardly facing impact portions 46 of the impact-receiving member 40 as the main shaft 30 rotates with respect to the actuator mechanism 50, as would occur during normal use of the electric drill. In this manner, the roller members 60 impart reciprocating motion along the longitudinal axis "L" to the main shaft 30. It would be readily understood by one skilled in the art that the roller members 60 generally ride along the rearward facing impact portions 46, and may impact all of the rearward facing impact portions 46, or impacts only higher portions of the rearward facing impact portions 46, depending on the speed of rotation of the impact-receiving member 40 with respect with the actuator mechanism 50.

[00065] The height, radius of curvature, shape and number of the impact portions 46 will affect the frequency and amplitude of the impacts of the roller members 60 on the rearward facing impact portions 46.

[00066] When the impact member 40 is in its disengaged position, the roller members 60 are removed from operative engagement with the plurality of impact portions 46.

[00067] A rotation-precluding link 90 is operatively connectable between the actuator mechanism 50 and a conventional electric drill, for substantially precluding rotation of the actuator mechanism 50 on the main shaft 30. The rotation-precluding link 90 comprises an actuator engaging portion 92 that is preferably in the form of an actuator engaging collar, and also a drill engaging portion 94 that is preferably in the form of a drill engaging collar. The rotation-precluding link 90 further comprises at least one arm portion, and in the preferred embodiment as illustrated, first and second arm portions 96,98, each interconnecting the actuator engaging portion 92 and the drill engaging portion 94.
The rotation-precluding link 90 is preferably made from nylon so as to be somewhat pliable and flexible, but other suitable materials may also be used. Further, a soft pliable material may be used on the back end 99 of the drill engaging collar 94 to permit more secure engagement with the forward portion of a conventional electric drill.

[00068] Further, the rotation-precluding link 90 should be made from a plastic material or materials in order to insulate an operator's hand from potential electric shock if the drill bit 29 happens to contact a live electrical wire during drilling.

[00069] The actuator engaging collar 92 of the rotation-precluding link 90 is securely connected to the main body 52 of the actuator mechanism 50. In this manner, when the drill engaging collar 92 engages the body of a conventional electric drill, the rotation-precluding link 90 precludes the actuator mechanism 50 from being rotated by rotation of the main shaft 30. Accordingly, when the conventional electric drill is operated, or in other words when its chuck is rotated, the main shaft 30, the secondary shaft 80, the impact-receiving member 40 and the drill bit chuck 35 are rotated about the longitudinal axes "L" and "LS", but the actuator mechanism remains stationary relative thereto. When the impact receiving member 40 is in its operatively engaged position due to the drill bit 29 engaging a workpiece (not shown), the actuator mechanism 50, specifically the roller members 60, engage the impact receiving member 40, specifically the impact member 46, as the main shaft rotates, to thereby impart reciprocating motion along the longitudinal axis to the impact receiving member 40.

[00070] The rotation-precluding link 90 extends rearwardly from the actuator mechanism 50 for engagement by the drill engaging collar 94 with the electric drill 28. The rotation-precluding link 90 precludes rotational movement of the actuator mechanism 50 with respect to the electric drill 28. Further, the rotation-precluding link 90 transmits a portion of the forces from the drill bit 29 and drill chuck 35 to the conventional electric drill (not shown), thus putting less stress on the drill chuck of the conventional electric drill.

[00071] As described above, the conventional drill bit 29 is caused to "hammer" into a piece of material as it rotates, thus causing a drill hole to be drilled readily even into hard materials, such as cement or concrete.

[00072] It has been found that with the hammer drill bit chuck attachment 20 of the present invention, which is operable without manual actuation in its operatively engaged position, there is reduced friction, reduced heat build up, reduced noise, reduced wear and improved drilling performance compared with conventional hammer drills, which have two sets of impacting steel teeth used to perform the hammering function. Heat build up is of particular concern under International Electrotechnical Commission IEC 60745 1:2001 (Hand Held Motor-Operated Electric Tools - Safety), and 60745 1:2001 (2003-01)( Hand Held Motor-Operated Electric Tools -Safety - particular requirements for drills and impact drills) and IEC 60745-2-1 ("Particular requirements for drills and impact drills"), as adopted by UL, CSA and other national governing bodies regulating safety in hand held power tools and accessories. An electric drill using the present invention experiences very minimal loss of speed due to the reduced friction between the roller members 50 and the impact-receiving member. Accordingly, the rotational energy is directed to the actual longitudinal vibration, and not to losses due to friction and heat. This is important for being able to achieve the maximum possible speed with a drill, and also for reduced wear of the hammer drill bit chuck attachment of the present invention and an electric drill being used. In contrast, an electric hammer drill actually operates at a significantly reduced rotational speed compared to the maximum rotational speed of the drill, due to the friction of the steel teeth.

[00073] As can be understood from the above description and from the accompanying drawings, the present invention provides a hammer drill bit chuck attachment that is inexpensive to manufacture, that is robust, wherein the frequency and amplitude of impacts can be adjusted or selected, wherein heat build up is minimized, wherein an electric drill used in conjunction with the hammer drill bit chuck attachment can be operated at lower rotational speeds, that is operable without direct manual activation, and wherein more power is available to be transferred to a drill bit from an electric drill used in conjunction with the hammer drill bit chuck attachment, all of which features are unknown in the prior art.

[00074] Other variations of the above principles will be apparent to those who are knowledgeable in the field of the invention, and such variations are considered to be within the scope of the present invention. Further, other modifications and alterations may be used in the design and manufacture of the hammer drill bit and hammer drill bit chuck attachment of the present invention without departing from the spirit and scope of the accompanying claims.

Claims

I CLAIM:

l. A hammer drill bit chuck attachment for use with a conventional electric drill, said hammer drill bit chuck attachment comprising:

a main shaft for secure engagement in the chuck of a conventional electric drill and defining a longitudinal axis;

an actuator mechanism mounted in freely rotatable relation on said main shaft;

an impact-receiving member connected to said main shaft for rotation therewith about said longitudinal axis and for longitudinal sliding movement substantially along said longitudinal axis between an operatively engaged position whereat said actuator mechanism engages said impact-receiving member as said main shaft rotates with respect to said actuator mechanism, to thereby impart reciprocating motion along said longitudinal axis to said impact-receiving member, and a disengaged position whereat said actuator mechanism is removed from said engagement with said impact-receiving member; and, a rotation-precluding link operatively connectable between said actuator mechanism and a conventional electric drill for substantially precluding rotation of said actuator mechanism on said main shaft.
2. The hammer drill bit chuck attachment of claim 1, wherein said impact-receiving member is connected to said main shaft for rotation therewith about said longitudinal axis by means of a secondary shaft defining a longitudinal axis, and wherein the longitudinal axis of said secondary shaft is axially aligned with the longitudinal axis of said main shaft.
3. The hammer drill bit chuck attachment of claim 1, wherein said secondary shaft comprises a threaded front portion, a rear main-shaft-engaging portion, and a stop flange disposed between said threaded front portion and said rear main-shaft-engaging portion.
4. The hammer drill bit chuck attachment of claim 1, wherein said rear main-shaft-engaging portion is polygonal in cross-section.
5. The hammer drill bit chuck attachment of claim 1, wherein said rear main-shaft-engaging portion is hexagonal in cross-section.
6. The hammer drill bit chuck attachment of claim 1, wherein said actuator mechanism is mounted in freely slidable relation on said main shaft.
7. The hammer drill bit chuck attachment of claim 1, wherein said main shaft has a rearward drill engaging portion, a forward spindle portion, and a stop flange disposed between said rearward drill engaging portion and said forward spindle portion.
8. The hammer drill bit chuck attachment of claim 1, wherein said actuator mechanism is slidably engaged on said forward spindle portion of said main shaft for movement along said longitudinal axis.
9. The hammer drill bit chuck attachment of claim 1, wherein said stop flange limits the movement in a rearward direction of said actuator mechanism on said main shaft.
10. The hammer drill bit chuck attachment of claim 1, wherein said main shaft is substantially hollow.
11. The hammer drill bit chuck attachment of claim 1, wherein said rotation-precluding link comprises an actuator engaging portion and a drill engaging portion.
12. The hammer drill bit chuck attachment of claim 1, wherein said rotation-precluding link further comprises at least one arm portion interconnecting said actuator engaging portion and said drill engaging portion.
13. The hammer drill bit chuck attachment of claim 1, wherein said rotation-precluding link further comprises first and second arm portions interconnecting said actuator engaging portion and said drill engaging portion.
14. The hammer drill bit chuck attachment of claim 1, wherein said actuator engaging portion comprises an actuator engaging collar.
15. The hammer drill bit chuck attachment of claim 1, wherein said drill engaging portion comprises a drill engaging collar.
16. The hammer drill bit chuck attachment of claim 1, wherein said rotation-precluding link is made from nylon
17. The hammer drill bit chuck attachment of claim 1, wherein said impact-receiving member has a plurality of impact portions and said actuator mechanism engages said plurality of impact portions in said operatively engaged position.
18. The hammer drill bit chuck attachment of claim 1, wherein said actuator mechanism has at least one roller member rotationally mounted thereon, and wherein when said actuator mechanism is in said operatively engaged position said at least one roller member engages said plurality of impact portions as said main shaft rotates with respect to said actuator mechanism, and wherein when said actuator mechanism is in disengaged position said at least one roller member is removed from said engagement with said plurality of impact portions.
19. The hammer drill bit chuck attachment of claim 1, wherein each of said impact portions comprises a ramp portion.
20. The hammer drill bit chuck attachment of claim 1, wherein said impact portions are rearwardly facing.
21. A rotation-precluding link for use with hammer drill bit chuck attachment, said rotation-precluding link comprising:

an actuator engaging portion; and, a drill engaging portion.
22. The hammer drill bit chuck attachment of claim 21, wherein said rotation-precluding link further comprises at least one arm portion interconnecting said actuator engaging portion and said drill engaging portion.
23. The hammer drill bit chuck attachment of claim 22, wherein said rotation-precluding link further comprises first and second arm portions interconnecting said actuator engaging portion and said drill engaging portion.
24. The hammer drill bit chuck attachment of claim 21, wherein said actuator engaging portion comprises an actuator engaging collar.
25. The hammer drill bit chuck attachment of claim 21, wherein said drill engaging portion comprises a drill engaging collar.