U.S. patent application number 17/374233 was filed with the patent office on 2021-11-04 for tool bit holder.
The applicant listed for this patent is MILWAUKEE ELECTRIC TOOL CORPORATION. Invention is credited to Xian Wei XU, Michael J. ZIMMERMANN.
Application Number | 20210339362 17/374233 |
Document ID | / |
Family ID | 1000005710760 |
Filed Date | 2021-11-04 |
United States Patent
Application |
20210339362 |
Kind Code |
A1 |
ZIMMERMANN; Michael J. ; et
al. |
November 4, 2021 |
TOOL BIT HOLDER
Abstract
A tool bit holder includes an inner sleeve in which a
longitudinal bore is defined in which a tool bit is receivable and
a detent is engageable with the tool bit for locking the tool bit
within the longitudinal bore. An outer sleeve surrounds the inner
sleeve and is movable relative to the inner sleeve between a
locking position, in which the detent is engaged with the tool bit
for locking the tool bit within the longitudinal bore, and a
release position, in which the detent may be disengaged from the
tool bit to permit removal of the tool bit from the longitudinal
bore. A spring is positioned between the inner sleeve and the outer
sleeve. The spring biases the outer sleeve toward the locking
position
Inventors: |
ZIMMERMANN; Michael J.; (New
Berlin, WI) ; XU; Xian Wei; (Dongguan City,
CN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
MILWAUKEE ELECTRIC TOOL CORPORATION |
Brookfield |
WI |
US |
|
|
Family ID: |
1000005710760 |
Appl. No.: |
17/374233 |
Filed: |
July 13, 2021 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
16517110 |
Jul 19, 2019 |
11065744 |
|
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17374233 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B23B 35/00 20130101;
B25B 23/0035 20130101; B23B 31/1071 20130101; B23B 2260/10
20130101; B23B 2231/04 20130101 |
International
Class: |
B25B 23/00 20060101
B25B023/00; B23B 31/107 20060101 B23B031/107 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 20, 2018 |
CN |
201810804116.9 |
Claims
1. A tool bit holder comprising: an inner sleeve in which a
longitudinal bore is defined in which a tool bit is receivable; a
shank received in the longitudinal bore of the inner sleeve; a
first detent engageable with the tool bit for locking the tool bit
within the longitudinal bore; a second detent received in a
circumferential groove of the shank; and an outer sleeve
surrounding the inner sleeve and movable relative to the inner
sleeve between a locking position, in which the first detent is
engaged with the tool bit for locking the tool bit within the
longitudinal bore, and a release position, in which the first
detent may be disengaged from the tool bit to permit removal of the
tool bit from the longitudinal bore, wherein the second detent is
maintained in the circumferential groove in the locking position
and the release position by the outer sleeve.
2. The tool bit holder of claim 1, wherein the longitudinal bore
includes a hexagonal cross-sectional shape, and wherein the shank
includes a hexagonal outer periphery slidably received in the
longitudinal bore along a longitudinal axis of the inner
sleeve.
3. The tool bit holder of claim 1, wherein the second detent limits
axial displacement of the inner sleeve relative to the shank.
4. The tool bit holder of claim 3, further comprising first and
second radial bores each extending through the inner sleeve,
between an outer periphery of the inner sleeve and the longitudinal
bore, in which the first and second detents are received,
respectively.
5. The tool bit holder of claim 1, wherein the circumferential
groove is a notch.
6. The tool bit holder of claim 1, further comprising a spring
positioned between the inner sleeve and the outer sleeve, wherein
the spring biases the outer sleeve toward the locking position.
7. The tool bit holder of claim 6, wherein the spring surrounds the
shank.
8. The tool bit holder of claim 1, further comprising a radial bore
extending through the inner sleeve, between an outer periphery of
the inner sleeve and the longitudinal bore, and wherein the first
detent is received in the radial bore.
9. The tool bit holder of claim 1, further comprising a shank
received in the longitudinal bore of the inner sleeve.
10. A tool bit holder comprising: an inner sleeve in which a
longitudinal bore is defined in which a tool bit is receivable; a
shank received in the longitudinal bore of the inner sleeve; a
first detent engageable with the tool bit for locking the tool bit
within the longitudinal bore; a second detent received in a
circumferential groove of the shank; an outer sleeve surrounding
the inner sleeve and movable relative to the inner sleeve between a
locking position, in which the first detent is engaged with the
tool bit for locking the tool bit within the longitudinal bore, and
a release position, in which the first detent may be disengaged
from the tool bit to permit removal of the tool bit from the
longitudinal bore; and a retaining ring secured to the shank,
wherein the outer sleeve is abuttable against the retaining ring to
limit axial displacement of the outer sleeve relative to the
shank.
11. The tool bit holder of claim 10, wherein the longitudinal bore
includes a hexagonal cross-sectional shape, and wherein the shank
includes a hexagonal outer periphery slidably received in the
longitudinal bore along a longitudinal axis of the inner
sleeve.
12. The tool bit holder of claim 10, wherein the second detent
limits axial displacement of the inner sleeve relative to the
shank.
13. The tool bit holder of claim 12, further comprising first and
second radial bores each extending through the inner sleeve,
between an outer periphery of the inner sleeve and the longitudinal
bore, in which the first and second detents are received,
respectively.
14. The tool bit holder of claim 10, wherein the circumferential
groove is a notch.
15. The tool bit holder of claim 10, further comprising a spring
positioned between the inner sleeve and the outer sleeve, wherein
the spring biases the outer sleeve toward the locking position.
16. The tool bit holder of claim 15, wherein the spring surrounds
the shank.
17. A method of operating a tool bit holder, the method comprising:
inserting a tool bit into a longitudinal bore of an inner sleeve
until a rear of the tool bit abuts a first detent positioned within
a radial bore through the inner sleeve; sliding the inner sleeve in
a rearward direction relative to an outer sleeve surrounding the
inner sleeve, thereby pushing a second detent in the rearward
direction along a circumferential groove of a shank; pushing the
first detent with the rear of the tool bit radially outward into a
channel in the outer sleeve, permitting continued insertion of the
tool bit into the longitudinal bore; and pushing the inner sleeve
in a forward direction toward a locked position in which the outer
sleeve displaces the first detent at least partially into the
longitudinal bore to prevent removal of the tool bit therefrom and
pushing the second detent in the forward direction along the
circumferential groove of the shank.
18. The method of claim 17, further comprising compressing a spring
into a retracted position with the sliding inner sleeve while the
outer sleeve remains stationary.
19. The method of claim 18, further comprising releasing the spring
in response to the first detent disengaging the rear of the tool
but, permitting the spring to rebound to an extended position and
pushing the inner sleeve in the forward direction.
20. The method of claim 19, further comprising: pulling the outer
sleeve in a forward direction towards an opening of the
longitudinal bore, with the inner sleeve remaining stationary,
against the bias of the spring; aligning the channel in the outer
sleeve with the first detent; and removing tool bit from the
longitudinal bore, thereby pushing the first detent radially
outward into the channel and out of the longitudinal bore.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of co-pending U.S. patent
application Ser. No. 16/517,110 filed on Jul. 19, 2019, now U.S.
Pat. No. 11,065,744, which claims foreign priority to Chinese
Patent Application No. 201810804116.9 filed on Jul. 20, 2018, the
entire contents of all of which are incorporated herein by
reference.
FIELD OF THE INVENTION
[0002] The present invention relates to tool bit holders, more
particularly to quick-release tool bit holders for use with rotary
power tools.
BACKGROUND OF THE INVENTION
[0003] To facilitate tool bit changes during a work operation,
rotary power tools often use quick-release bit holders in which
different tool bits are receivable. Such bit holders axially secure
tool bits therein by one or more ball detents, which when released
permit removal of the tool bit from the bit holder.
SUMMARY OF THE INVENTION
[0004] The present invention provides, in one aspect, a tool bit
holder including an inner sleeve in which a longitudinal bore is
defined in which a tool bit is receivable, a detent engageable with
the tool bit for locking the tool bit within the longitudinal bore,
an outer sleeve surrounding the inner sleeve and movable relative
to the inner sleeve between a locking position, in which the detent
is engaged with the tool bit for locking the tool bit within the
longitudinal bore, and a release position, in which the detent may
be disengaged from the tool bit to permit removal of the tool bit
from the longitudinal bore, and a spring positioned between the
inner sleeve and the outer sleeve. The spring biases the outer
sleeve toward the locking position
[0005] The present invention provides, in another aspect, a tool
bit holder including an inner sleeve in which a longitudinal bore
is defined in which a tool bit is receivable, a shank received in
the longitudinal bore of the inner sleeve, first and second radial
bores each extending through the inner sleeve, between an outer
periphery of the inner sleeve and the longitudinal bore, first and
second detents received, respectively, in the first and second
radial bores, the first detent being engageable with the tool bit
for locking the tool bit within the longitudinal bore, an outer
sleeve surrounding the inner sleeve and movable relative to the
inner sleeve between a locking position, in which the first detent
is engaged with the tool bit for locking the tool bit within the
longitudinal bore, and a release position, in which the first
detent may be disengaged from the tool bit to permit removal of the
tool bit from the longitudinal bore, one of a circumferential
groove or a notch in an outer periphery of the shank in which the
second detent is received to limit axial displacement of the inner
sleeve relative to the shank to a distance less than an axial
length of the circumferential groove or notch, and a spring
positioned between the inner sleeve and the outer sleeve. The
spring biases the outer sleeve toward the locking position.
[0006] The present invention provides, in yet another aspect, a
method of operating a tool bit holder. The method includes
inserting a tool bit into a longitudinal bore of an inner sleeve
until a rear of the tool bit abuts a detent positioned within a
radial bore through the inner sleeve, sliding the inner sleeve in a
rearward direction relative to an outer sleeve surrounding the
inner sleeve, compressing a spring into a retracted position with
the sliding inner sleeve while the outer sleeve remains stationary,
pushing the ball detent with the rear of the tool bit radially
outward into a channel in the outer sleeve, permitting continued
insertion of the tool bit into the longitudinal bore, and releasing
the spring in response to the ball detent disengaging the rear of
the tool bit, permitting the spring to rebound to an extended
position and push the inner sleeve in a forward direction toward a
locked position in which the outer sleeve displaces the ball detent
at least partially into the longitudinal bore to prevent removal of
the tool bit therefrom.
[0007] Other aspects of the invention will become apparent by
consideration of the detailed description and accompanying
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a cross-sectional view of a tool bit holder in
accordance with an embodiment of the invention.
[0009] FIG. 2 is a cross-sectional view of the tool bit holder of
FIG. 1, illustrating insertion of a tool bit.
[0010] FIG. 3 is a cross-sectional view of the tool bit holder of
FIG. 1, illustrating the tool bit fully inserted in the tool bit
holder
[0011] FIG. 4 is a cross-sectional view of the tool bit holder of
FIG. 1, illustrating the tool bit being removed.
[0012] FIG. 5 is an exploded perspective view of the tool bit
holder of FIG. 1.
[0013] FIG. 6 is a perspective cutaway view of a tool bit holder in
accordance with another embodiment of the invention.
[0014] Before any embodiments of the invention are explained in
detail, it is to be understood that the invention is not limited in
its application to the details of construction and the arrangement
of components set forth in the following description or illustrated
in the following drawings. The invention is capable of other
embodiments and of being practiced or of being carried out in
various ways. Also, it is to be understood that the phraseology and
terminology used herein is for the purpose of description and
should not be regarded as limiting.
DETAILED DESCRIPTION
[0015] FIGS. 1 and 2 illustrate a tool bit holder 10 for adapting
different types and sizes of tool bits 12 for use with a rotary
power tool (e.g., drill driver, an impact driver, etc.). Such tool
bits 12 are interchangeably coupled to the bit holder 10 without
the use of tools. The bit holder 10 includes an inner sleeve 14, an
outer sleeve 18 surrounding the inner sleeve 14 and slidable
relative to the inner sleeve 14, and a shank 22 upon which both the
inner sleeve 14 and the outer sleeve 18 are supported. The shank 22
includes a hexagonal cross-sectional shape and a circumferential
groove 26 in which a ball detent of a quick-release mechanism of
the rotary power tool is receivable for axially securing the bit
holder 10 to the rotary power tool. Alternatively, the shank 22 may
be clamped by multiple jaws of a drill chuck.
[0016] The inner sleeve 14 includes a longitudinal bore 30 defining
a longitudinal axis 34 coaxial with the shank 22. The bore 30
includes a hexagonal cross-sectional shape corresponding to that of
the shank 22, thereby providing a snug sliding fit between the
inner sleeve 14 and the shank 22. The bore 30 also extends through
the inner sleeve 14, defining opposite front and rear openings 38,
42. Tool bits 12 are receiveable through the front opening 38,
whereas the shank 22 protrudes from the rear opening 42.
[0017] As previously stated, the inner sleeve 14 is slidable
relative to the shank 22 along the longitudinal axis 34. The tool
holder 10 also includes first and second pluralities of radial
bores 46a, 46b spaced axially from each other along the axis 34,
and first and second pluralities of ball detents 50a, 50b received
in the radial bores 46a, 46b, respectively. The bores 46a, 46b
extend radially through the inner sleeve 14, between a cylindrical
outer periphery of the inner sleeve 14 and the bore 30. The radial
bore 46a tapers in a radially inward direction, thereby defining
openings into the bore 30 having a smaller diameter than the
diameters of the respective ball detents 50a received in the bore
46a. Therefore, the ball detents 50a, 50b are prevented from
falling into the bore 30. As shown in FIG. 5, the bores 46a are
spaced approximately 120 degrees apart from each other.
Alternatively, the bores 46a may be spaced approximately 180
degrees apart from each other.
[0018] In the illustrated embodiment of the tool bit holder 10, the
bores 46b are spaced 180 degrees apart from each other for receipt
of two of the ball detents 50b. Unlike the bores 46a, the bores 46b
are cylindrical and have a diameter nominally greater than that of
the ball detents 50b. Alternatively, only a single bore 46b and
ball detent 50b may be used. As shown in FIGS. 1-4, the ball
detents 50b are received within a circumferential groove 54 in the
shank 22 having an axial length L. In an alternative embodiment of
the tool bit holder 100 shown in FIG. 6, the ball detents 50b are
received within corresponding, discrete notches 78 in the shank 22
rather than a circumferential groove 54.
[0019] With reference to FIGS. 1 and 2, the outer sleeve 18
includes a cylindrical inner periphery 18a corresponding to a
cylindrical outer periphery 14a of the inner sleeve 14, thereby
providing a snug sliding fit between the outer sleeve 18 and the
inner sleeve 14. The outer sleeve 18 also includes a rear end 58
having a round aperture 62 through which the shank 22 extends. In
alternative embodiments (not shown), the aperture 62 may be
substantially hexagonal. The bit holder 10 further includes a
retaining ring 66 secured to the shank 22 against which the rear
end 58 of the outer sleeve 18 is abuttable and a spring 70 seated
between an internal shoulder 90 defined by the rear end 58 of the
outer sleeve 18 and a rear end 94 of the inner sleeve 14. The
spring 70 also surrounds the shank 22. As such, the spring 70 is
located within an annular chamber 98 defined by the shank 22, the
cylindrical inner periphery 18a of the outer sleeve 18, the rear
end 94 of the inner sleeve 14, and the shoulder 90 on the outer
sleeve 18. Because the placement of the ball detents 50b in the
circumferential groove 54 limits axial movement of the inner sleeve
14 relative to the shank 22 to a displacement D that is less than
the axial length L of the groove 54, the spring 70 biases the rear
end 58 of the outer sleeve 18 against the retaining ring 66 and the
inner sleeve 14 and the outer sleeve 18 apart from each other.
[0020] The outer sleeve 18 also includes a channel 74 in the
cylindrical inner periphery of the outer sleeve 18 proximate the
radial bores 46a. When the channel 74 is misaligned with the ball
detents 50a coinciding with a "locking" position of the outer
sleeve 18 as shown in FIG. 1, the outer sleeve 18 displaces the
ball detents 50a radially inward to protrude into the longitudinal
bore 30 and clamp against a tool bit 12 to axially secure the tool
bit 12 within the bore 30. In the illustrated embodiment, the ball
detents 50a are biased radially inward to protrude into the bore 30
by the spring 70. The outer sleeve 18 is slidable relative to the
inner sleeve 14 from its locking position to a "release" position
(FIG. 2), against the bias of the spring 70, to align the channel
74 with the ball detents 50a. When aligned, the ball detents 50a
are at least partially receiveable in the channel 74, and are also
removed from the bore 30. Therefore, the clamping force applied to
the tool bit 12 is released, permitting it to be removed from the
bit holder 10.
[0021] In contrast, the ball detents 50b are continuously engaged
with the cylindrical inner periphery 18a of the outer sleeve 18,
regardless of its position. Therefore, the ball detents 50b are
maintained within the circumferential groove 54 when the outer
sleeve 18 is in the locking position and the release position.
[0022] FIG. 1 illustrates the tool bit holder 10 with the outer
sleeve 18 in the locking position and without a tool bit 12
received in the holder 10. As stated above, when the outer sleeve
18 is in the locking position, the ball detents 50a radially
protrude into the bore 30. Additionally, the spring 70 is situated
within the chamber 98 in an extended position. Upon insertion of
the tool bit 12 into the bore 30, a rear 12a of the tool bit 12
contacts the ball detents 50a. Because the ball detents 50a are
misaligned with the channel 74, they cannot be radially displaced
from the bore 30. Rather, continued rearward movement of the tool
bit 12 causes the inner sleeve 14 to slide relative to the shank 22
while the outer sleeve 18 remains stationary in the locking
position, compressing the spring 70 into a retracted position.
After the inner sleeve 14 is displaced by the amount D, the ball
detents 50a are pushed radially outward into the channel 74 of the
outer sleeve 18, removing the ball detents 50a from the bore 30 and
creating a sufficient amount of clearance for the tool bit 12 to be
inserted past the ball detents 50a. Upon the ball detents 50a
encountering a circumferential groove 82 in the tool bit 12, the
spring 70 rebounds towards the extended position to push the inner
sleeve 14 forward toward a locked position, driving the ball
detents 50a into a wedged or clamped position between the
cylindrical inner periphery 18a of the outer sleeve 18 and the tool
bit 12. While the inner sleeve 14 is displaced forward, the outer
sleeve 18 remains stationary in the locking position relative to
the shank 22. Alternatively, the spring 70 may rebound to push the
inner sleeve 14 forward by less than the displacement D, causing
the ball detents 50a to wedge against a conical interior surface
74a (FIG. 1) transitioning the channel 74 to the cylindrical inner
periphery 18a.
[0023] To release the bit 12, the outer sleeve 18 is pulled towards
the front opening 38 against the bias of the spring 70 toward its
release position, aligning the channel 74 in the outer sleeve 18
with the ball detents 50a, permitting radially outward movement of
the ball detents 50a and removal of the tool bit 12. The
illustrated embodiment of the holder 10 also includes a magnet 86
coupled to an end of the shank 22 within the bore 30 for retaining
a tool bit 12 within the bore 30. Therefore, the magnet 86 may
retain the tool bit 12 within the bore 30 even when the outer
sleeve 18 is in the release position. In this manner, the tool bit
12 cannot fall out of the bore 30 once the outer sleeve 18 is moved
to the release position. Rather, the user must grasp the tool bit
12 and pull it from the bore 30 for removal. Alternatively, the
magnet 86 may be omitted from the holder 10.
[0024] Various features of the invention are set forth in the
following claims.
* * * * *