U.S. patent application number 10/104276 was filed with the patent office on 2003-09-25 for keyless chuck with backup key operation.
Invention is credited to Corcoran, Jerry Alvin.
Application Number | 20030178795 10/104276 |
Document ID | / |
Family ID | 27788389 |
Filed Date | 2003-09-25 |
United States Patent
Application |
20030178795 |
Kind Code |
A1 |
Corcoran, Jerry Alvin |
September 25, 2003 |
KEYLESS CHUCK WITH BACKUP KEY OPERATION
Abstract
A chuck that can be operated with or without a key, depending
upon the amount of torque desired. The jaws are controlled by
rotation of a screw ring about the axis of the chuck body that
slides the jaws along jaw passages by engagement with teeth on the
jaw surfaces. The screw ring is housed in a tightening knob that
has a planar ring gear perpendicular to the chuck body axis. A tail
section is rigidly attached to the chuck body below the tightening
knob and houses a pinion gear that matingly engages the planar ring
gear and rotates in concert with the tightening knob. Insertion of
a hex key into a recess in the pinion gear allows the application
of additional torque. Alternate embodiments incorporate a idler
gear to reverse pinion gear rotation; locate the pinion gear in the
tightening knob with the planar ring gear in the tail section; and
utilize a planar ring gear on both the tail section and the
tightening knob with a floating ring to house the pinion gear
between the planar ring gears.
Inventors: |
Corcoran, Jerry Alvin;
(Canby, OR) |
Correspondence
Address: |
MARK S. HUBERT
3816 NE 136TH PLACE
PORTLAND
OR
97230
US
|
Family ID: |
27788389 |
Appl. No.: |
10/104276 |
Filed: |
March 22, 2002 |
Current U.S.
Class: |
279/62 ;
279/902 |
Current CPC
Class: |
B23B 31/1238 20130101;
Y10T 279/17632 20150115; B23B 2260/078 20130101 |
Class at
Publication: |
279/62 ;
279/902 |
International
Class: |
B23B 031/12 |
Claims
What is claimed is:
1. A chuck capable of keyless and keyed operations comprising: a
chuck body housing a plurality of adjustable jaws adapted for
gripping and releasing tools; a means for keyless operation of said
chuck whereby rotation of said means opens and closes said jaws;
and a means for keyed operation of said chuck jaws whereby said
means receives a hex key that when rotated opens and closes said
jaws.
2. The chuck of claim 1 wherein said chuck is a drill chuck.
3. A chuck comprising: an axially bored chuck body with a forward
end and a rear end, and a plurality of jaw passages formed therein
inclined axially forward to intersect said axial bore in an
angularly spaced arrangement; a plurality of jaws with gear teeth
formed thereon and slideably positioned in said jaw passages; a
circumferential groove formed in said chuck body about a
longitudinal axis of said chuck body intersecting said jaw passages
so as to expose said gear teeth; a generally cylindrical tightening
knob with a gripable outer surface rotatably attached about said
forward end of said chuck body and a planar ring gear formed on a
face thereof and an internal threaded ring having rotational
dependence with said jaw teeth to enable sliding movement of said
jaws within said jaw passages when said tightening knob is rotated
about the axis of said chuck body with respect to said chuck body;
and a cylindrical tail piece fixedly attached to the rear section
of said chuck body with a rotatable pinion gear accessibly housed
therein and adapted to rotate in response to rotation of said
planar ring gear; wherein said pinion gear defines a recess adapted
to receive a matingly formed key device for enabling rotation of
said pinion gear.
4. The chuck of claim 3 wherein said rear section of said chuck
body is adapted for receiving a driven shaft of a drill.
5. The chuck of claim 3 wherein said key device is a hex
wrench.
6. The chuck of claim 3 wherein said rotatable pinion gear is
adapted to rotate in response to a rotation of said planar ring
gear by engagement with said planar ring gear on said tightening
knob.
7. The chuck of claim 3 wherein said cylindrical tail section
further comprises an internally housed idler gear, and wherein said
rotatable pinion gear is adapted to rotate in response to a
rotation of said planar ring gear by engagement with said idler
gear wherein said idler gear is in simultaneous engagement with
said pinion gear and said planar ring gear.
8. A chuck comprising: an axially bored chuck body with a forward
end and a rear end and a plurality of jaw passages formed therein
and inclined axially forward to intersect said axial bore in an
angularly spaced arrangement; a plurality of jaws with gear teeth
formed thereon and slideably positioned in said jaw passages; a
circumferential groove formed in said chuck body about a
longitudinal axis of said chuck body intersecting said jaw passages
so as to expose said gear teeth; a cylindrical tightening knob with
a gripable outer surface rotatably attached about said forward end
of said chuck body with a rotatable pinion gear accessibly housed
therein and an internal threaded ring having rotational dependence
with said jaw teeth to enable sliding movement of said jaws within
said jaw passages when said tightening knob is rotated about the
axis of said chuck body with respect to said chuck body; and a
cylindrical tail section fixedly attached to the rear section of
said chuck body with a planar ring gear formed on a face thereof
matingly engaged with said pinion gear and adapted to rotate in
response to rotation of said pinion gear; wherein said pinion gear
defines a recess adapted to receive a key device for enabling
rotation of said pinion gear.
9. The chuck of claim 8 wherein said rear section of said chuck
body is adapted for receiving a driven shaft.
10. The chuck of claim 8 wherein said key device is a hex
wrench.
11. A chuck comprising: a axially bored chuck body with a forward
end and a rear end and a plurality of jaw passages formed therein
and inclined axially forward to intersect said axial bore in an
angularly spaced arrangement; a plurality of jaws with gear teeth
formed thereon and slideably positioned in said jaw passages; a
circumferential groove formed in said chuck body about a
longitudinal axis of said chuck body intersecting said jaw passages
so as to expose said gear teeth; a cylindrical tightening knob with
a gripable outer surface rotatably attached about said forward end
of said chuck body with a first planar ring gear formed on a face
thereof and an internal threaded ring having rotational dependence
with said jaw teeth to enable sliding movement of said jaws within
said jaw passages when said tightening knob is rotated about the
axis of said chuck body with respect to said chuck body; a
cylindrical tail section fixedly attached to the rear section of
said chuck body with a second planar ring gear formed on a face
thereof; and a floating ring situated between said tightening knob,
and said tail section wherein said floating ring accessibly houses
a rotatable pinion gear that defines a recess adapted to receive a
key device for enabling rotation of said pinion gear; wherein said
pinion gear is simultaneously engaged with said first and said
second planar ring gears and is adapted to rotate coincident with
rotation of said first planar ring gear, said second planar ring
gear or both first and second planar ring gears when rotated in
opposite angular directions.
12. The chuck of claim 11 wherein said rear section of said chuck
body is adapted for receiving a driven shaft.
13. The chuck of claim 11 wherein said key device is a hex
wrench.
14. A chuck comprising: a axially bored chuck body with a forward
end and a rear end and a plurality of jaw passages formed therein
and inclined axially forward to intersect said axial bore in an
angularly spaced arrangement; a plurality of jaws with gear teeth
formed thereon and slideably positioned in said jaw passages; a
circumferential groove formed in said chuck body about a
longitudinal axis of said chuck body intersecting said jaw passages
so as to expose said gear teeth; a cylindrical tightening knob with
a gripable outer surface rotatably attached about said forward end
of said chuck body with a first planar ring gear formed on a face
thereof and an internal threaded ring having rotational dependence
with said jaw teeth to enable sliding movement of said jaws within
said jaw passages when said tightening knob is rotated about the
axis of said chuck body with respect to said chuck body; a
cylindrical tail section fixedly attached to the rear section of
said chuck body with a second planar ring gear formed on a face
thereof; and a floating ring situated between said tightening knob,
and said tail section wherein said floating ring is adapted to
receive a keyed device therein with a profile that matingly
corresponds to said first planar ring gear and said second planar
ring gear and align it into simultaneous meshing engagement with
said first planar ring gear and said second planar ring gears;
wherein rotation of said keyed device is coincident with rotation
of said first planar ring gear and said second planar ring gear
when planar gears are rotated in opposite angular directions with
respect to each other.
15. The chuck of claim 14 wherein said keyed device is a drill
chuck.
16. The chuck of claim 14 wherein said rear section of said chuck
body is adapted for receiving a driven shaft.
17. The chuck of claim 14 wherein said key device is a hex
wrench.
18. A drill chuck comprising: a axially bored chuck body with a
forward end and a rear end and a plurality of coaxially arranged
jaw passages formed therein and inclined axially forward to
collectively intersect said axial bore; a plurality of jaws with
gear teeth formed on a proximal section thereon and slideably
positioned in said jaw passages; a circumferential groove formed in
said chuck body about a longitudinal axis of said chuck body
intersecting said jaw passages so as to expose said gear teeth; a
cylindrical tightening knob with a gripable outer surface rotatably
attached about said forward end of said chuck body with a planar
ring gear formed on a face thereof and an internal screw ring
having rotational dependence with said jaw gear teeth to enable
sliding movement of said jaws within said jaw passages when said
tightening knob is rotated about the axis of said chuck body with
respect to said chuck body; and a cylindrical tail section fixedly
attached to the rear section of said chuck body with a rotatable
pinion gear accessibly housed therein and engaged to said planar
ring gear on said tightening knob; wherein said pinion gear defines
a recess adapted to receive a key device for enabling rotation of
said pinion gear.
19. The chuck of claim 18 wherein said key device is a hex
wrench.
20. The chuck of claim 18 wherein said key device is a screwdriver.
Description
BACKGROUND OF THE INVENTION
[0001] The present invention relates to a keyless tool chuck, and
more particularly relates to an improvement in construction of a
chuck for firmly holding a tool such as a drill bit or a driver bit
of electric work devices without assistance by a chuck key. This
invention relates to a chuck for use with rotating equipment such
as drills. Such rotating equipment is commonly driven manually or
in the case of power drivers, electrically, hydraulicly or
pneumatically. More particularly, the present invention relates to
a keyless style of chuck which may be tightened or loosened by hand
and can alternatively be tightened or loosened by rotation of a key
after insertion into a recess formed in the chuck body.
[0002] Both hand and powered tool drivers are well known. The
general configuration is a rear rotational driver, mechanically
coupled to a chuck by threaded engagement or via a tapered sleeve
that mates into a corresponding recess in the chuck body. The chuck
has any number of circumferentially equally spaced jaws that are
advanced concurrently both axially outward and radially inward from
a front orifice. It is the advancement of these jaws that grip a
tool or bit. The chuck may be used to hold any one of a multitude
of tools such as screw or nut drivers and cutting, shaping or
grinding bits, although the most common is a twist drill. With such
a diverse selection of tool bits, the diameters and configurations
of the shanks vary considerably from circular to polygonal in cross
section. For this reason the chuck is adjustable over a relatively
wide range.
[0003] Numerous chucks have been developed and are well known in
the art. The most common type is found on the household hand drill.
This is perhaps the most simple configuration with three jaws
approximately spaced circumferentially 120 degrees apart from each
other. Each jaw is housed in an angularly disposed passageway in
the chuck body configured so that rotation of the chuck body in one
direction with respect to a constrained nut engaging the jaws
forces the jaws into gripping relationship with the tool bit.
Counter rotation acts to release the gripping relationship. The
rotation is commonly accomplished through the use of a key. If
sufficient torque can be developed by hand rotation of the chuck, a
key is not necessary. This is a desirable configuration in that
bits can be quickly removed or inserted and lost or damaged keys do
not hinder the process.
[0004] In the current state of the art, key and keyless chucks both
have several disadvantages. First if they require a key, it is made
of a specific size as all keys are not interchangeable. Keys are
easily lost and the engagement teeth can become stripped.
Replacement keys can often be hard to find. Second, this type of
tightening is slow as it requires insertion and separate tightening
at different axial positions around the chuck. If it is a hand
tightening chuck it often does not hold the tool bit secure enough
for arduous operations, or conversely it holds the tool bit too
firm such that hand release of the bit is extremely difficult. The
disadvantages of the keyed and keyless chucks are in direct
opposition to their respective advantages. It would be desirable to
have a hybrid style of chuck that is keyless with a backup keyed
operation to remedy all of these drawbacks in the existing chucks.
It would be desirable if the keyed operation was accomplished by a
standard and commonly available key. Elimination of the multiple
keying operations would serve to maintain the ease and speed of
tightening the tool bits in the keyed fashion as would less turns
of the key to advance and tighten the jaws. It would also be
desirable to have a keyless chuck that requires fewer components or
has a lower manufacturing cost.
SUMMARY OF THE INVENTION
[0005] In accordance with the invention, a keyless chuck includes a
rotatable hand tightening knob with a planar ring gear on the back
surface lying perpendicular to the axis of rotation. A pinion gear
is housed in an internal cavity between the chuck body and a tail
piece and is in mating engagement with the ring gear such that the
pinion gear rotates as the tightening knob is rotated when
advancing and closing the jaws. The pinion gear has a recess which
is accessible through an orifice in the tail piece and is adapted
accept a key device such as an hex key, or a screwdriver that when
inserted and rotated, can provide additional torque to open or
close the jaws. A second embodiment utilizes a substantially
similar configuration but incorporates an idler gear to reverse
rotation between the pinion gear and the tightening knob.
[0006] In a third embodiment of the keyless chuck, a keyless chuck
includes a rotatable hand tightening knob with a pinion gear housed
in a void formed in the tightening knob. The tail piece of the
chuck has an planar ring gear on the front surface that lies
perpendicular to the axis of rotation where the ring gear is in
mating engagement with the pinion gear such that the pinion gear
rotates as the knob is rotated to advance and close the jaws. The
pinion gear has a recess that is accessible through an orifice in
the tightening knob and corresponds to a key device such as an hex
key, that when inserted and rotated, can provide additional torque
to open or close the jaws.
[0007] In a fourth embodiment a keyless chuck includes a rotatable
hand tightening knob with an planar ring gear formed on its back
surface lying perpendicular to the axis of rotation. A tail piece
has a planar ring gear on a front surface lying perpendicular to
the axis of rotation and positioned such that its teeth oppose the
teeth of the planar ring gear of the tightening knob. A pinion gear
is housed in an internal cavity of a floating ring that fits
between the knob and tail piece such that the pinion gear is
matingly engaged with both the tail piece ring gear and the knob
ring gear. The floating ring and pinion gear have corresponding
recesses to accept a keyed device such as a hex key, that when
inserted and rotated, will rotate the knob and tail piece in
opposite directions thereby providing additional torque to open or
close the jaws and closing the jaws in less turns as in the first
and second embodiments.
[0008] In the final embodiment a keyless chuck includes a rotatable
hand tightening knob with a planar ring gear formed on the back
surface lying perpendicular to the axis of rotation. A set of two
gears, a first pinion gear and a second idler gear are housed in an
internal cavity of the tail piece such that the idler gear is in
mating engagement with the ring gear. The idler gear rotates as the
knob is rotated to advance and close the jaws. This causes the
pinion gear to rotate in the opposite direction of the idler gear.
The tail piece and pinion gear have corresponding recesses to
accept a keyed device such as an hex key, that when inserted and
rotated, can provide additional torque to open or close the jaws.
This embodiment changes the direction that the pinion gear is
rotated in the preferred embodiment to accomplish the same
effect.
[0009] Accordingly, it is an object of the present invention to
provide an improved keyless chuck with the ability to use a key to
gain additional mechanical advantage to tighten or loosen the
jaws.
[0010] It is a further object of the present invention to provide
an improved chuck that uses a standard fastener tool to tighten or
loosen the jaws.
[0011] It is yet another object of the present invention to provide
an improved keyless chuck that eliminates the multiple keying
operations common to the chuck industry.
[0012] It is still a further object of the present invention to
provide an improved keyless chuck capable of an increased
tightening torque over conventional chucks.
[0013] It is a final object of the present invention to provide an
improved chuck that would require a minimum number of key turns to
advance and tighten the jaws thus serving to increase the ease and
speed of tightening the tool bits in the keyed fashion.
[0014] The subject matter of the present invention is particularly
pointed out and distinctly claimed in the concluding portion of
this specification. However, both the organization and method of
operation, together with further advantages and objects thereof,
may best be understood by reference to the following description
taken in connection with accompanying drawings wherein like
reference characters refer to like elements. Other objects,
features and aspects of the present invention are discussed in
greater detail below.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 is a perspective view of the keyless chuck with the
jaws fully advanced;
[0016] FIG. 2 is an exploded view of the keyless chuck showing the
interconnection between the pinion gear and the tightening knob's
ring gear;
[0017] FIG. 3 is a cross sectional view of the chuck showing the
chuck body, tail piece and tightening knob;
[0018] FIG. 4 is a cross sectional view of a second embodiment
chuck showing the chuck body, a modified tail piece, tightening
knob and idler gear;
[0019] FIG. 5 is a cross sectional view of a third embodiment chuck
with a showing the chuck body, tail piece and modified tightening
knob;
[0020] FIG. 6 is a cross sectional view of a fourth embodiment
chuck showing the chuck body, tail piece, tightening knob and
floating ring; and
[0021] FIG. 7 is a cross sectional view of the fourth embodiment
chuck showing the chuck body, tail piece, tightening knob and an
internally housed floating ring.
DETAILED DESCRIPTION
[0022] The chuck apparatus according to a preferred embodiment of
the present invention comprises a chuck body, a tightening knob,
and a tail piece. Referring to FIG. 1, a perspective view of the
keyless chuck with the jaws fully advanced, keyless chuck 2 is
comprised of cylindrical chuck body 4 which is housed inside tail
piece 6 and tightening knob 8. Tightening knob 8 and tail piece 6
are arranged in a stacked configuration. Jaws 10 extend axially
from chuck body 4. Dust ring 12 (only illustrated in FIG. 1) is
attached to tightening knob 8 and spans across clearance gap 56
(see FIG. 3) onto chuck body 4 so as to prevent debris from fouling
the operation of chuck 2. Tightening knob 8 has a cylindrical
configuration terminating in a radiused frusticonical face 16.
Grooves 14 are formed in cylindrical face 18 and extend partially
along its longitudinal axis. Pinion gear 20 and key recess 22 can
be seen protruding through tail piece bore 24 in tail piece 6.
[0023] Looking at FIG. 2, an exploded view of the keyless chuck, it
can be seen that pinion gear 20 with pinion gear teeth 27, has
shoulder 30 extending perpendicularly from gear face 32. Shoulder
30 has key recess 22 formed therein that matingly engages with hex
key 34. Tightening knob 8 has rear face 36 with planar ring gear 28
and teeth 38 formed thereon. The interconnective alignment of
pinion gear 20 with ring gear 28 and tail piece recess 24 is
illustrated.
[0024] FIG. 3, a cross sectional view of the chuck, illustrates the
physical orientation of the internal components of chuck 2. Tail
piece 6 is fixedly attached to chuck body 4. Shoulder 30 acts as a
plain bearing for pinion gear 20 to rotate on within tail piece
bore 24 and also acts to retain pinion gear 20 within bore 24.
Pinion gear teeth 27 matingly engage planar ring gear teeth 38.
Recess 40 is bored longitudinally through chuck body 4. Three jaw
passages 42 are bored inclinedly through chuck body 4 and are in
communication with recess 40. Jaw passages 42 are oriented so as to
be converging passages and are spaced approximately angularly
equidistant about the longitudinal axis of chuck body 4. Jaws 10
are of a generally cylindrical configuration with rack teeth 52 and
tapered faces 58 located on the exterior longitudinal surface of
jaw 10 approximately 180 degrees apart. Jaws 10 reside in jaw
passage 42 oriented such that rack teeth 52 face into annular
groove 50 of chuck body 4 at an acute angle with respect to the
longitudinal axis of chuck body 4. Threaded ring 48 frictionally
fits into annular recess 46 in tightening knob 8 such that threads
54 extend into annular groove 50 in chuck body 4 and engage with
rack teeth 52 of jaws 10. There is a clearance gap 56 between chuck
body 4 and tightening knob 8.
[0025] FIG. 4, a cross sectional view of a second embodiment chuck
with a modified tail piece, illustrates first modified tail piece
60 with tail piece idler gear bore 62 and tail piece pinion gear
bore 64. Pinion gear 20 is secured into pinion gear bore 64 by
pinion gear shoulder 30. Tail piece idler gear 66 is secured into
tail piece idler gear bore 62 by idler gear shoulder 70. Idler gear
66 engages planar ring gear 38 and pinion gear 20.
[0026] FIG. 5, a cross sectional view of a third embodiment chuck,
shows pinion gear 20 housed by shoulder 30 in orifice 82 of first
modified tightening knob 80. Pinion gear 20 resides in void 84.
Recess 40 is bored longitudinally through chuck body 4. Three jaw
passages 42 are bored inclinedly through chuck body 4 and are in
communication with recess 40. Jaw passages 42 are orientated so as
to be converging passages and are spaced approximately equidistant
about the longitudinal axis of chuck body 4. Jaw 10 is of a
generally cylindrical configuration with rack teeth 52 and tapered
face 58 located on the exterior longitudinal surface of jaw 10 180
degrees apart. Jaw 10 resides in jaw passage 42 oriented such that
rack teeth 52 face into annular groove 50 at an acute angle with
respect to the longitudinal axis of chuck body 4. Threaded ring 48
frictionally fits into annular recess 92 in first modified
tightening knob 80 such that threads 54 extend into annular groove
50 in chuck body 4 and engage with rack teeth 52 of jaw 10. There
is a clearance gap 56 between chuck body 4 and first modified
tightening knob 80. Second modified tail piece 86 has a hollow
cylindrical shape with upper flange 88 and lower flange 90. Upper
flange 88 forms planar ring gear 92 having teeth 96 which engages
teeth 27 of pinion gear 20. Lower flange 90 is fixedly attached to
chuck body 4.
[0027] FIG. 6, a cross sectional view of a fourth embodiment chuck,
shows external floating ring 100 housed in a stacked arrangement
between third modified tail piece 102 and second modified
tightening knob 104. Second modified tightening knob 104 has planar
ring 106 with teeth 108 formed on a surface thereof that is
perpendicular to the longitudinal axis of chuck body 4. Third
modified tail piece 102 has planar ring gear 110 with teeth 112
formed on a surface thereof that is perpendicular to the
longitudinal axis of chuck body 4 and parallel planar ring gear
106. Floating ring 100 is of a generally hollow cylindrical shape
with recess 118. Floating ring 100 fits into the space defined by
tail piece groove 114 and tightening knob groove 116. Shoulder 30
on pinion gear 20 resides in floating ring recess 118 and teeth 30
of pinion gear 20 matingly engage teeth 108 and 112 simultaneously.
FIG. 7, a cross sectional view of the fifth embodiment chuck, shows
internal floating ring 120 housed in a stacked arrangement between
fourth modified tail piece 122 and third modified tightening knob
124. Third modified tightening knob 124 has planar ring 126 with
teeth 128 formed on a surface thereof that is perpendicular to the
longitudinal axis of chuck body 4. Fourth modified tail piece 122
has planar ring gear 130 with teeth 132 formed on a surface thereof
that is perpendicular to the longitudinal axis of chuck body 4 and
parallel planar ring gear 126. Floating ring 120 is of a generally
hollow cylindrical shape with recess 136. Floating ring 120 resides
in groove 134 cut in third modified tightening knob 124. Chuck key
138 has shoulder 140 and teeth 142 formed thereon. Shoulder 140 can
be fit into recess 136 such that chuck key teeth 142 will matingly
engage tightening knob planar ring gear teeth 128 and tail piece
planar ring gear teeth 132 simultaneously.
[0028] Now referring to FIGS. 1-3 it can be seen that in operation,
rotating tightening knob 8 with respect to tail piece 6 causes
threads 54 of threaded ring 48 to engage rack teeth 52 so as to
slidingly advance or retract jaws 10 in jaw passages 42 until
tapered faces 58 of jaws 10 contact each other or until bottom face
90 contacts abutment 92 of chuck body 4. Rotating tightening knob 8
with respect to tail piece 6 also causes pinion gear 20 to rotate
on shoulder 30 in tail piece bore 24 by virtue of its engagement
with teeth 38 of ring gear 36. This mating engagement between
pinion gear 20 and ring gear 36 can also allow additional torque to
be exerted on tightening knob 8 to slidingly advance or retract
jaws 10 in jaw passages 42 when hex key 34 is inserted into key
recess 22 and rotated. Although jaws 10 can be tightened or
loosened by hand manipulation of tightening knob 8 with respect to
tail piece 6, jaws 10 may also be tightened or loosened with
additional mechanical advantage provided by a rotating hex key 34.
Although the mechanical advantage is provided through six sided hex
key 34, any key style tool configuration, as commonly known in the
industry, would function equally as well provided that key recess
22 was configured to match.
[0029] FIG. 4 is a second embodiment wherein first modified tail
piece 60 houses idler gear 66 in mated engagement with pinion gear
20. Idler gear 66 is in mated engagement with ring gear 38. This
configuration accomplishes a substantially similar jaw tightening
and loosening function as described in the preferred embodiment
with a reverse rotation of pinion gear 20.
[0030] FIG. 5 is a third embodiment wherein pinion gear 20 is
housed in first modified tightening knob 80 and ring gear 92 is
located on upper flange 88 of second modified tail piece 86. Manual
operation of this embodiment in the keyless mode is the same as
that of the preferred embodiment to the user, however internally,
as first modified tightening knob 80 is rotated with respect to
second modified tail piece 86, pinion gear 20 is rotated by mating
engagement with tail piece ring gear 92. When hex key 34 is
inserted into pinion gear recess 22 and rotated, teeth 27 will
rotate second modified tail piece 86 and chuck body 4 thereby
revolving jaws 10 around the longitudinal axis of chuck body 4 such
that rack teeth 52, which are engaged with stationary threads 54 of
threaded ring 48, advance or retract jaws 10 slidingly along jaw
passages 42. In this manner additional torque and mechanical
advantage can be added to tighten or loosen the jaws.
[0031] Referring to the fourth embodiment of FIG. 6 the advancement
of jaws 10 is still accomplished by rotation of jaw teeth 52 with
respect to threads 54 of threaded ring 48 as in all of the
embodiments. This alternate embodiment incorporates planar ring
gears on both second modified tightening knob 104 and third
modified tail piece 102. With pinion gear 20 engaged with
tightening knob planar ring gear 106 and tail piece planar ring
gear 110, both second modified tightening knob 104 and third
modified tail piece 102 are rotated simultaneously when hex key 34
is inserted into key recess 22 and rotated for keyed operation.
This reduces the number of rotations of key 34 that are required to
fully open or close jaws 10 as compared to chuck embodiments
incorporating only one planar ring gear, but requires more torque
to accomplish each rotation. The floating ring 100 houses pinion
gear 20 in a stationary position about the axis of chuck body 4
while second modified tightening knob 104 and third modified tail
piece 102 revolve about this axis.
[0032] The fifth embodiment in FIG. 7 functions similarly to the
fourth alternate embodiment since both embodiments utilize two
planar ring gears for keyed operation, except there is no pinion
gear 20 rotated by hex key 34. Instead shoulder 140 of a
conventional chuck key 138, standardized in the industry, is
inserted into recess 136 of internal floating ring 120 such that
teeth 142 matingly engage teeth 128 of tightening knob planar ring
gear 126 and teeth 132 of tail piece planar ring gear 130. Floating
ring 120 maintains key 138 in a stationary position about the axis
of chuck body 4 while third modified tightening knob 124 and fourth
modified tail piece 122 revolve about this axis.
[0033] This additional mechanical advantage in the "key mode"
allows the jaws in all embodiments to be tightened beyond what
could be accomplished by hand manipulation in the "keyless chuck"
mode. This is useful in situations where the tool to be gripped is
not of uniform diameter or when working on particularly hard
surfaces. This additional mechanical advantage also allows for the
jaws to be loosened when the tool has stopped rotating in the work
material and the driver has input additional torque to tighten the
jaws on the tool beyond what could be accomplished by hand
manipulation.
[0034] The coupling of the driver mechanism (not part of this
invention) to chuck body 4 is accomplished in several ways as is
well known in the industry. Commonly, tapered or threaded shafts or
sleeves are fixedly engaged in the longitudinal bore 40 of chuck
body 4. Although chuck body 4 is illustrated with a smooth bore 40
this bore can also be threaded or otherwise adapted to receive the
driver mechanism's drive shaft.
[0035] The amount of mechanical advantage or torque available to
tighten or loosen the jaws of the various chuck embodiments is
determined through the gearing ratios, configurations and designs
of the pinion gear, idler gear, planar ring gears and check key as
is well known in the industry.
[0036] While a preferred embodiment of the present invention and
four alternate embodiments have been shown and described, it will
be apparent to those skilled in the art that many changes and
modifications may be made without departing from the invention in
its broader aspects. The appended claims are therefore intended to
cover all such changes and modifications as fall within the true
spirit and scope of the invention.
* * * * *