Title:
Slip proof device in combination with a bit for a hand drill chuck
Kind Code:
A1


Abstract:
A slip proof device for a chuck includes a recessed area adapted to receive therein a collar, a through hole defined through a bottom face defining the recessed area to allow a bit to extend therethrough, and a first threaded hole defined in a periphery of a side wall defining the recessed area so as to adapt to correspond to one of three cavities in the collar and to allow a first abutting element to extend through the first threaded hole and one of the cavities to secure the slip proof device relative to the chuck. The bit includes a free end adapted to be clamped by the three claws of the chuck and a truncated surface longitudinally defined on the bit such that a second abutting element is able to abut the truncated surface to secure the bit relative to the slip proof device.



Inventors:
Chen, Jih-ming (Dali City, TW)
Application Number:
10/330211
Publication Date:
07/01/2004
Filing Date:
12/30/2002
Assignee:
CHEN JIH-MING
Primary Class:
International Classes:
B23B31/107; B23B31/12; B24B41/00; (IPC1-7): B24B41/00
View Patent Images:



Primary Examiner:
TALBOT, MICHAEL
Attorney, Agent or Firm:
VENABLE LLP (WASHINGTON, DC, US)
Claims:

What is claimed is:



1. A slip proof device in combination with a bit for a chuck having a collar with three claws movably received in the collar and three cavities equally defined in a periphery of the collar, the slip proof device comprising: a recessed area adapted to receive therein the collar; a through hole defined through a bottom face defining the recessed area to allow the bit to extend therethrough; and a first threaded hole defined in a periphery of a side wall defining the recessed area so as to adapt to correspond to one of the three cavities in the collar and to allow a first abutting element to extend through the first threaded hole and one of the cavities to secure the slip proof device relative to the chuck; and the bit comprising a free end adapted to be clamped by the three claws of the chuck and a truncated surface longitudinally defined on the bit such that a second abutting element is able to abut the truncated surface to secure the bit relative to the slip proof device.

2. The slip proof device in combination with a bit as claimed in claim 1, wherein the slip proof device further has a second threaded hole defined in the periphery of the side wall to allow the second abutting element to extend through the second threaded hole to abut the truncated surface of the bit so as to secure the bit.

3. The slip proof device in combination with a bit as claimed in claim 1, wherein the slip proof device further has two cutouts defined in the side face defining the recessed area to adapt to correspond to remaining two cavities of the chuck.

4. The slip proof device in combination with a bit as claimed in claim 2, wherein the slip proof device further has two cutouts defined in the side face defining the recessed area to adapt to correspond to remaining two cavities of the chuck.

Description:

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a slip proof device in combination with a bit for a hand drill chuck, and more particularly to a slip proof device adapted to a chuck so as to obviate slip between the chuck and the bit.

[0003] 2. Description of Related Art

[0004] A conventional hand drill is equipped with numerous bits for different requirements. Before using the hand drill, the operator normally will mount a proper bit on a chuck of the hand drill by using a chuck key. In order to have better understanding of how the conventional hand drill works, refer to FIG. 5, wherein the hand drill has a chuck (40) ready to clamp a bit (50). The chuck (40) has a collar (41) with a through hole (42) radially extending through the collar (41) and three claws (43) movably received in the collar (41) to clamp the bit (50). When the conventional hand drill is in use, the operator uses the chuck key (not shown) to separate the claws (43), after which, a proper bit (50) is inserted into the space defined by the claws (43). Then an abutting element (52) threadingly extends into the through hole (42) to abut a truncated surface (51) such that the bit (50) is secured among the claws (43). Although this type of hand drill has been used successfully for years, drawbacks still impede the operator, which are:

[0005] {circle over (1)} Engagement between the claws (43) and the bit (50) is not secured even with the assistance of the abutting element (52) so that the bit may not be driven to rotate by the turning chuck during operation, or the bit may even separate from the hand drill.

[0006] {circle over (2)} When the diameter of the bit is small, the distance among each of the claws is too small to have an effective clamping force to hold the bit.

[0007] {circle over (3)} If the diameter is small, the abutting element should be small so as to properly abut a side face of the bit, which results in that the abutting force of the abutting element is not effective.

[0008] To overcome the shortcomings, the present invention tends to provide an improved slip proof device in combination with a bit to mitigate and obviate the aforementioned problems.

SUMMARY OF THE INVENTION

[0009] The primary objective of the present invention is to provide an improved slip proof device adapted to engage with the chuck of the hand drill so as that the requirement of the abutting element is eliminated.

[0010] Another objective of the present invention is to provide an improved bit incorporated with the slip proof device such that the bit is able to be securely clamped by the hand drill.

[0011] Other objects, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012] FIG. 1 is a perspective view of the slip proof device in combination with a bit of the present invention;

[0013] FIG. 2 is an exploded perspective view of the slip proof device and the bit in FIG. 1;

[0014] FIG. 3 is a schematic side plan view showing the engagement of the slip proof device with the bit;

[0015] FIG. 4 is a schematic view showing the bit incorporation with the slip proof device of the present invention; and

[0016] FIG. 5 is a cross sectional view showing the relationship between the bit and the claws of the conventional hand drill.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0017] With reference to FIGS. 1 and 2, a chuck (30) which is substantially the same as the conventional one has a first collar (31) and a second collar (32) received in the first collar (31). The second collar (32) has three cavities (33) equally defined in a periphery of the second collar (32) and three claws (34) movably received in the second collar (32).

[0018] A slip proof device (10) in accordance with the present invention is adapted to engage with the chuck (30). The slip proof device (10) is U-shaped in cross section and has a recessed area (11), a through hole (12) defined in a bottom face defining the recessed area (11), a first threaded hole (14) defined in a side face of the recessed area (11) to correspond to a first bolt (141), two cutouts (15) peripherally defined in the side face of the recessed area (11) and a second threaded hole (16) defined in the side face of the recessed area (11) to correspond to a second bolt (161). It is noted that the first threaded hole (14) is aligned with one of the cavities (33) of the chuck (30) and the two cutouts (15) are defined to align with the remaining two cavities (33) of the chuck (30).

[0019] A bit (20) in accordance with the present invention has a free end (21) adapted to correspond to the three claws (34) of the chuck (30) and a truncated surface (22) longitudinally defined along the bit (20).

[0020] With reference to FIGS. 3 and 4, when the slip proof device (10) and the bit (50) are to be incorporated with the chuck (30), the free end (21) of the bit (20) is first inserted through the through hole (12) and into a space defined by the three claws (34) of the chuck (30). Then the operator uses the chuck key (not shown) to tighten the three claws (34) to secure the bit (20) in the chuck (30). Thereafter, the slip proof device (10) is adapted to engage with the second collar (32) of the chuck (30) with the first threaded hole (14) aligned with one of the cavities (33) in the second collar (32) and the two cutouts (15) aligned with the remaining two cavities (33) of the chuck (30). Then the second abutting element (26) threadingly extends into the second threaded hole (16) to abut the truncated surface (22) of the bit (20) such that the bit (20) is firmly clamped in the slip proof device (10). After the bit (20) is secured in the chuck (30) and the slip proof device (10), the first abutting element (141) threadingly extends through the first threaded hole (14) and into the aligned cavity (33) of the second collar (32).

[0021] With such an arrangement, it is noted that when the slip proof device (10) incorporated with the bit (20) is adapted to engage with the chuck (30), the problem raised by the too-small diameter of the bit is obviated. Furthermore, because the bit (20) has the truncated surface (22) which is firmly abutted by a free end of the second abutting element (161), the operator need not worry that the bit (20) may slip during operation.

[0022] It is to be understood, however, that even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.