U.S. patent application number 11/192803 was filed with the patent office on 2005-11-24 for quick change adaptor for rotary machines.
Invention is credited to Jochim, James David, Lovchik, Christopher Scott.
Application Number | 20050260052 11/192803 |
Document ID | / |
Family ID | 28045714 |
Filed Date | 2005-11-24 |
United States Patent
Application |
20050260052 |
Kind Code |
A1 |
Lovchik, Christopher Scott ;
et al. |
November 24, 2005 |
Quick change adaptor for rotary machines
Abstract
In one embodiment, the present invention includes an apparatus
including an adaptor body having a first end to be coupled to a
rotary device and a second end having a tapered portion, and a tool
adaptor dimensioned to fit within the tapered portion, the tool
adaptor having a receiving end to receive a tool, such as a
bit.
Inventors: |
Lovchik, Christopher Scott;
(Pearland, TX) ; Jochim, James David; (Nassau Bay,
TX) |
Correspondence
Address: |
TROP PRUNER & HU, PC
8554 KATY FREEWAY
SUITE 100
HOUSTON
TX
77024
US
|
Family ID: |
28045714 |
Appl. No.: |
11/192803 |
Filed: |
July 29, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11192803 |
Jul 29, 2005 |
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10392452 |
Mar 18, 2003 |
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6939213 |
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60367642 |
Mar 25, 2002 |
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Current U.S.
Class: |
409/182 |
Current CPC
Class: |
Y10T 408/957 20150115;
B23Q 3/12 20130101; B23B 31/1071 20130101; B23B 31/202 20130101;
Y10T 279/17752 20150115; Y10T 409/306608 20150115; Y10T 279/15
20150115; Y10T 409/309408 20150115 |
Class at
Publication: |
409/182 |
International
Class: |
B23C 001/20 |
Claims
1-17. (canceled)
18. An apparatus comprising: a body having a first end and a second
end to be coupled to a collet for a rotary machine, the first end
having an opening to receive a tool; and a spring constrained
within the body to spring lock the tool.
19. The apparatus of claim 18, wherein the body has a first
threaded portion for coupling to the collet and a second threaded
portion for receiving the spring.
20. The apparatus of claim 18, wherein the spring is tapered.
21. The apparatus of claim 18, wherein the rotary machine comprises
a router.
22. An apparatus comprising: a body having a first end and a second
end to be coupled to an output shaft of a rotary machine; a spring
coupled to the first end of the body; and a cap mounted around the
spring and tensioned thereby, the cap fitted in movable relation to
the body, the cap having an opening to receive a tool.
23. The apparatus of claim 22, wherein the tool is inserted in a
first rotational direction and removed in a second rotational
direction.
24. The apparatus of claim 22, wherein the body comprises a collet
nut screwed onto the output shaft.
25. The apparatus of claim 22, wherein the spring is threaded onto
a mating thread on the first end of the body.
26. The apparatus of claim 25, wherein a portion of the spring
extends above the first end of the body.
27. The apparatus of claim 22, wherein the cap is axially
constrained via a groove in the body.
28. The apparatus of claim 22, wherein the spring is axially
tensioned when the tool is inserted and axially relaxed when the
tool is removed.
29. The apparatus of claim 22, wherein the spring includes a tang
to fit within a groove within the cap.
30-34. (canceled)
35. An apparatus comprising: a nut having a first end and a second
end to be coupled to a collet shaft of a rotary machine, the first
end having an opening to receive a tool; and a spring having a
first end threaded onto the nut to spring lock the tool.
36. The apparatus of claim 35, wherein the nut has a first internal
thread to mate with the collet shaft and a second internal thread
to mate with the spring.
37. The apparatus of claim 35, wherein the first end of the spring
is tapered.
38. The apparatus of claim 35, wherein the tool is locked via
rotation while being inserted into the nut.
39. The apparatus of claim 35, wherein the nut is to constrain the
spring when the nut is coupled to the collet shaft.
Description
[0001] This application claims priority to the U.S. Provisional
Patent Application No. 60/367,642 filed on Mar. 25, 2002 in the
name of Christopher Scott Lovchik and James David Jochim entitled
TOOL FREE, QUICK RELEASE, SPRING ACTUATED CHUCK.
BACKGROUND
[0002] The present invention relates to an adaptor device, and more
particularly to a quick-change adaptor for cutting tools.
[0003] Currently, no simple and inexpensive quick-change (QC)
devices exist for swapping cutting bits in and out of standard
rotary cutting machines. Machines such as routers, grinders, and
small mills have the capacity to use thousands of cutting bits but
unfortunately lack an easy or quick way to switch between these
bits. Standard bit changing procedures typically require the user
to either manipulate two individual tools or manipulate one tool
while the preventing the machine shaft from rotating.
[0004] For example, routers such as CRAFTSMAN.TM. routers
(available from Sears Co., Chicago, Ill.) use a split collet and
jam nut to secure a cutting bit to a router. In such a
configuration, the collet uses the bore in the router shaft for
alignment. The bore is the only precision surface needed, and the
outside diameter and the threads can have considerable error with
little to no adverse affect on the performance of the router.
However, no quick adaptor exists for such a router or other rotary
machine.
[0005] Thus a need exists for an adaptor to provide for quick and
easy tool changing. More so, a need exists to provide such quick
tool changing that can handle errors in a machine shaft and
threaded adaptor device.
SUMMARY OF THE INVENTION
[0006] Embodiments of the present invention provide a compact and
inexpensive way to allow quick and easy tool changing. Such devices
can be readily actuated with one hand and requires no additional
tooling or procedures (for either tool insertion or release). In
certain embodiments, a device may be used in automated bit changers
in certain machines. The small size of the device allows it to be
used with small hand grinders or woodworking routers without
significantly increasing the effective machine spindle length. As
such, most existing tools can be retrofitted with this device
without affecting their performance. Certain embodiments of the
device may also incorporate several safety features that protect
against inadvertent release of a spinning bit.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 shows an exploded view of a preferred embodiment of a
quick-change assembly.
[0008] FIG. 2 shows an exploded view of a bit adaptor assembly in
accordance with one embodiment of the present invention.
[0009] FIG. 3 shows an exploded view of a bit adaptor assembly in
accordance with another embodiment of the present invention.
[0010] FIG. 4 shows a cross-sectional view of a QC adaptor assembly
in accordance with one embodiment of the present invention.
[0011] FIG. 5 shows a cross-sectional view of the QC adaptor of
FIG. 4 without a bit adaptor assembly present.
[0012] FIG. 6 shows a fully assembled quick-change device without a
bit or actuating collar shroud in accordance with one embodiment of
the present invention.
[0013] FIG. 7 shows an exploded view of an alternate QC assembly in
accordance with one embodiment of the present invention.
[0014] FIG. 8 shows a partial cross-sectional view of another
alternate embodiment of a QC assembly.
[0015] FIG. 9 shows an exploded view of a spring chuck assembly in
accordance with one embodiment of the present invention.
[0016] FIG. 10 shows an exploded, partial cross-section view of a
spring chuck assembly in accordance with another embodiment of the
present invention.
[0017] FIG. 11 shows an exploded view of a spring chuck assembly in
accordance with still another embodiment of the present
invention.
[0018] FIG. 12 shows a shaft clamp embodiment in accordance with
the present invention.
DETAILED DESCRIPTION
[0019] Referring to FIG. 1, shown is a quick-change assembly in
accordance with one embodiment of the present invention. As shown
in FIG. 1, the assembly includes a quick-change body (1), a
quick-change body adaptor nut (2), a QC body adaptor nut retaining
ring (3), two force compensation half rings (4), locking balls (5),
an actuating spring (6), an actuating collar (7), an actuating
collar cam pin (8), an actuating collar shroud (9), and a bit
adaptor assembly (10) which, in this embodiment may be an adaptor
for a 1/2" bit.
[0020] In forming the QC assembly, the QC body adaptor nut
retaining ring (3) may be inserted into a retaining ring groove
(19) on the quick-change body (1), and the quick-change body
adaptor nut (2) may be slipped down onto the body (1) and snapped
over the ring (3). In this embodiment an internal groove (20)
(shown in FIG. 4) in the quick-change body adaptor nut (2) captures
the retaining ring (3) and may prevent the nut (2) from being
separated from the body (1) without rigidly constraining the nut
(2) to the body (1).
[0021] In further formation of the assembly, the locking balls (5)
may be inserted into holes (21) on the QC body (1) and two force
compensation half rings (4) may be inserted into a groove (22)
(also shown in FIG. 4) on the QC body adaptor nut (2). The
actuating spring (6) is inserted into the actuating collar (7) and
both may be slipped over the base of the QC body (1). The actuating
collar cam pin (8) is inserted through the cam slot (23) in the
actuating collar (7) and into the threaded hole (24) in the QC body
(1). Once the actuating collar cam pin (8) is in place the movement
of the actuating collar (7) may be constrained to only that allowed
by the geometry of the cam slot (23). The actuating collar shroud
(9) is pressed onto the outside of the actuating collar (7),
locking the shroud (9) and actuating collar (7) together.
[0022] Any number of bit adaptor assemblies can be constructed
using either a collet system or a setscrew system as shown in FIGS.
2 and 3 respectively. Adaptor assemblies may be made to accommodate
any standard or non-standard shank size. FIG. 2 shows an example
embodiment of a {fraction (1/2)}" bit adaptor assembly (10), which
is constructed by inserting a 1/2" cutting bit (14) into a 1/2" bit
adaptor collet (12), which is then threaded into the 1/2" bit
adaptor body (11). Two bit adaptor torque pins (13) are threaded
into the bit adaptor body (11) and may carry the machine spindle
torque from the QC body (1) to the 1/2" bit adaptor body (11) and
finally to the cutting bit (14). In various embodiments, bit
adaptor body (11) may be tapered to fit within adaptor body (1).
While the angle of such taper may vary, in certain embodiments the
angle may be greater than approximately 15.degree..
[0023] FIG. 3 shows an example embodiment of a 1/4" bit adaptor
assembly (15) for a standard 1/4" diameter shank bit. In one
embodiment, this may be the preferred way to secure a 1/4" bit. As
shown in FIG. 3, assembly (15) includes a 1/4" bit adaptor body
(16), two bit adaptor setscrew/torque pins (17), and a 1/4" shank
bit (18). The assembly may be constructed by inserting the 1/4"
cutting bit (18) into the bit adaptor body (16). Two bit adaptor
setscrew/torque pins (17) are threaded into the bit adaptor body
and tightened against the bit shank. These setscrews/torque pins
(17) may carry the machine spindle torque from the QC body (1) to
the 1/4" bit adaptor body (16) and finally to the cutting bit
(18).
[0024] Referring now to FIG. 4, shown is a cross section of a QC
adaptor assembly in accordance with one embodiment of the present
invention. Referring also to FIG. 5, shown is the QC adaptor of
FIG. 4 without a corresponding bit adaptor assembly. The non-ridged
constrain of the QC body (1) through the adaptor nut retaining ring
(3) to the quick-change body adaptor nut (2) allows the collet
interface surface (33) to align true to the tool without any
off-axis influence from the threads of the quick-change body
adaptor nut (2). Using this configuration, the quick-change body
adaptor nut (2) and the collet interface surface (33) may be
matched to fit and run true on any existing any removable collet
and nut tool interface.
[0025] Referring now to FIG. 6, shown are details of the cam slot
(23) in the actuating collar (7) in accordance with one embodiment
of the present invention. Operationally, the actuating spring (6)
may push the actuating collar (7) down. Due to the cam pin (8)
riding in the cam slot (23), the actuating collar (7) may be forced
to rotate as it moves down. As the actuating collar (7) moves down
a tapered surface (25) (shown in FIG. 5) on its inner diameter, the
actuating collar (7) presses the locking balls (5) inward and into
a tapered groove (26) (shown in FIG. 4) on the bit adaptor body
(11), thereby preloading the bit adaptor assembly (10) upward into
the QC body (1) taper. To insert the bit adaptor assembly (10), a
user may simply lift up on the actuating collar shroud (9). Such
action may remove the inward pressure on the locking balls (5),
allowing them to move outward, which then allows the bit adaptor
assembly (10) to be inserted into the quick-change assembly.
[0026] In certain embodiments, the exterior taper on the bit
adaptor body (11) may match the interior taper of the quick-change
body (1) to insure accurate axial bit alignment. The heads of the
bit adaptor torque pins (13) may protrude and be constrained by
grooves or sculpted slots (27) on the QC body (1). These sculpted
slots (27) may allow the machine spindle torque to be transferred
through the QC body (1) to the torque pins and finally to the
spinning bit. More so, sculpted slots (27) permit a bit adaptor
assembly (10) to be inserted in any angular position, as the slots
(27) will guide bit adaptor assembly (10) to the proper seating. As
such the bit adaptor assembly (10) can be inserted blind and it
will still be properly engaged in adaptor body (1). In various
embodiments, simply lifting up on the actuating collar (7) may
release the bit adaptor assembly (10).
[0027] In certain embodiments, the cam slot (23) may provide
several safety features. Such features may include an inertial
lock, an anti-ball jam lock, as well as audible and visual
indication of correct bit insertion. The inertial lock may utilize
the rotational motion of the actuating collar (7) dictated by the
control (i.e., cam) slot (23) in the actuating collar (7) and cam
pin (8) attached to the QC body (1). If the actuating collar is
pulled up, as if to release the bit assembly, it is forced to
rotate opposite the running direction of the machine spindle. As
the machine is spun up, the actuating collar (7) lags the QC body
(1) because of its rotational inertia. This lag forces the cam pin
(8) to travel down the cam slot (23), which pushes the actuating
collar (7) further down, which adds to the inward force of the
locking balls (5) that holds the bit adaptor assembly (10) in
place. The crescent shape of the cam slot (23) maximizes the
inertial force by providing and increasing force angle as the
actuating collar (7) rotates. The geometry of the cam slot (23) may
also ease actuation of the actuating collar (7) by reducing the
force angle when the actuating collar (7) is depressed.
[0028] Full rotation of the actuating collar (7), as dictated by
the cam slot (23), may be required in order to insert or remove a
bit adaptor assembly (10) in certain embodiments. Internal ball
relief grooves (28) (see FIG. 1) on the inner diameter of the
actuating collar (7) allow the locking balls (5) to fully retract
only at the proper rotational position. If for any reason the
actuating collar (7) is jammed and is prevented from fully
rotating, the locking balls (5) will not allow insertion or removal
of the bit adaptor assembly (10).
[0029] Referring again to FIG. 6, in certain embodiments tapered
surfaces (29) on the actuating collar (7) also may engage the bit
adaptor torque pins (13) and help to rotate the collar (7) to the
correct position during insertion and help unseat the bit adaptor
assembly (10) during removal. When the actuating collar (7) is
pressed up, the actuating collar (7) is rotated opposite the
running direction of the router, and the bit adaptor assembly (10)
is pushed down and out by the tapered surfaces (29). When the
actuating collar (7) is fully depressed, the cam pin (8) moves into
and catches in a detent (30) in the control slot (23). This is the
cocked position. A bit adaptor assembly (10) can only be installed
when the quick-change body (1) is in this position.
[0030] In certain embodiments, a bit adaptor assembly (10) is
installed by simply pushing it into quick-change body (1). The bit
adaptor torque pins (13) engage the tapered surfaces (29) on the
actuating collar (7), forcing it to rotate in the running direction
of the router. Once the collar (7) is rotated out of the control
slot detent (30), the actuation spring (6) takes over and it snaps
the actuating collar (7) down, grabbing the bit adaptor assembly
(10). The snap of the actuating collar (7) provides an audible
indication that the bit adaptor assembly (10) has been properly
seated. Due to the rotation of the actuating collar (7), a further
visual indication may be given when marks on the QC body (1) and on
the actuating collar (7) are in alignment. If these marks do not
line up, then the bit adaptor assembly (10) has not been properly
installed.
[0031] The force-compensating half rings (4) provide another safety
feature in certain embodiments. During operation the half rings (4)
are thrown outward by centrifugal acceleration against a tapered
surface (31) (shown in FIG. 4) on the inner diameter of the
actuating collar (7), thereby forcing it down. This downward force
helps assure that the collar (7) does not lift up during operation,
thereby releasing the spinning bit assembly (10). This downward
force is proportional to the mass of the half rings (4), their
distance from the axis of rotation, the angle of the tapered
surface (31) and the square of the spindle's angular velocity--and
may be optimized for the particular machine application. In an
alternate embodiment, these half rings (4) may also act as a
retaining ring by preventing the actuating collar (7) from slipping
off of the QC body (1) by protruding partially under the inner lip
(32) on the actuating collar (7). The inner diameter of the half
rings (4) may be slightly smaller than the root diameter groove
(22) on the QC body adaptor nut (2). This causes the half rings (4)
to spring away from the QC body nut (2) at all times and insures
that the QC body nut (2) cannot slip out of the actuating collar
(7). Even with no tapered surface (31), these half rings (4) may
provide resistance to the upward motion of the actuating collar
(7).
[0032] The centrifugal force referred to earlier may produce a
proportional frictional force between the half rings (4) and the
actuating collar (7), which may oppose any motion in the collar
(7), either up or down, that might result in bit assembly (10)
release. The more massive the half rings (4) become the more
frictional force that they are able to generate at any given
rotational speed. More so, while described as half rings, it is to
be understood that force compensation rings need not be fully
semicircular and in certain embodiments, more than two such ring
portions may be present.
[0033] Quick-change devices in accordance with embodiments of the
present invention may be adapted to tools that do not have a
removable collet as well as tools that have just a simple shaft.
This is done by colleting to the shaft as shown in FIG. 7. As shown
in the embodiment of FIG. 7, the quick-change body (1) may be split
(35) at the end that engages a complex machine shaft (34). The QC
body is slipped over the machine shaft (34) and the collet nut (36)
is threaded up the QC body (1). This nut (36) forces the collet
closed, thereby clamping to the machine shaft and eliminating
motion between it and the QC body.
[0034] As discussed above, in various embodiments a quick-change
assembly may be dimensioned to not significantly increase the
effective machine spindle length. In certain embodiments, an
assembly may vary depending on the machine in which it will be
used. Further, while tool sizes may vary, in certain embodiments
the quick-change assembly may accommodate tools having shanks up to
1/2" inch.
[0035] As discussed above, certain routers use a split collet and
jam nut to secure a bit. Referring now to FIG. 8, in certain
embodiments a quick-change assembly may use a shaft adaptor (80),
with an aligning surface (82), inserted into the bore in the router
shaft (84) and a solid body (86), with a mating aligning surface,
that threads onto the router. Such threads may be designed to be
loose enough to handle any minor errors in the router shaft and
allow the aligning surfaces to draw the quick-change into alignment
with the router bore. In other aspects, this embodiment may be
similar to the embodiment of FIG. 1.
[0036] The embodiment of FIG. 8 works well provided that the errors
in the shaft and threads are not too great. However, precision
bores may suffer from more significant radial errors and axial
errors found in the outside diameters and threads of the bore.
[0037] Though many routers are within expectable ranges for such a
quick-change design, other routers have both radial errors
(concentricity) and axial errors (angular run out) that may exceed
the capabilities of the embodiment of FIG. 8.
[0038] To prevent such deformation, the embodiment of FIG. 1 may be
used. This embodiment advantageously may be formed using a two-part
assembly having a quick-change head (i.e., body (1)) with the shaft
adaptor (i.e., collet interface surface (33)) machined directly
into it, and a separate threaded base (i.e., nut (2)) attached to
the quick-change head by a retaining ring (3). The threaded base
can move or float as the assembly is tightened down onto the
router, allowing this configuration to handle extreme errors in
both the shaft and the thread while maintaining precision
alignment.
[0039] In other embodiments, a spring-based quick-change adaptor
may be used. FIG. 9 shows an embodiment of a spring chuck assembly.
It includes a split-collet nut (101), a locking spring (102), a
quick release cap (103), and a bit (104). In one embodiment, the
device may be designed to accept a single shaft diameter (smaller
bits can be accommodated by using shaft adaptors), although in
other embodiments a device can accept any given bit diameter.
Henceforth this standard shaft diameter will be referred to as the
"bit shaft" or the "bit shaft diameter".
[0040] In the embodiment of FIG. 9, the split-collet nut (101)
screws onto the rotary output shaft of the machine being used. The
internal diameter of the split collet has no greater than a 0.001"
clearance with the bit shaft diameter. The locking spring (102) is
taper wound in the left hand direction. The internal diameter of
the small side of the spring taper is set to be at least 0.005"
smaller than the bit shaft diameter. The locking spring is threaded
onto, and is retained by, a left hand thread (110) on the
split-collet nut (101). This thread allows a set number of winds to
be treaded onto the collet. Additional winds of the locking spring
remain above the split-collet. The quick release cap (103) mounts
over the locking spring (102) and an internal lip (111) snaps into
a groove (112) in the split-collet nut (101). The bit is inserted
into the chuck assembly by lightly pushing it into the split-collet
while simultaneously rotating it in the counter-clockwise
direction. To remove the bit, it may be rotated counter-clockwise
and simultaneously pulled out.
[0041] This device works by utilizing the tension in the spring to
hold the bit tight (and ground the input torque) when the machine
output shaft rotates in the clockwise direction (cutting
direction). In addition, the tension in the spring also serves to
close or clamp the split collet around the bit, also grounding the
torque. The phenomenon being utilized is described by the equation
T.sub.out=T.sub.in/e.sup.(.beta..nu.), where T.sub.in is the
tension at one end of the spring, .beta. is the total angle through
which the spring wire is wound, .nu. is the coefficient of friction
between the spring and the surface that it is wound about, and
T.sub.out is the tension at the opposite end of the spring. The
locking spring is sized by setting T.sub.in to the maximum torque
applied to the bit divided by the bit shaft radius. T.sub.out is
set to the tension created by stretching the wire around the bit or
collet. The equation is then solved for the total wrap angle
(.beta.). This is the number of wraps of the spring needed to
assure that the spring will not slip on the shaft. The same
calculation is done to determine the number of locking spring wraps
needed to ground the torque to the split-collet. It is important to
note that this phenomenon acts only in only one direction (which is
determined by the direction of spring wrap) and is the major reason
that bit insertion and removal is so easy.
[0042] In certain embodiments, the insertion and removal of bits
can be made even easier by the addition of the mechanism shown in
FIG. 10. Or, the locking spring can be captured using an internal
thread, which can be used to adapt this device to machines with
existing split-collet shafts, as shown in FIG. 11.
[0043] Referring now to FIG. 10, shown is a partial cross-section
including a split-collet nut (101), a locking spring (102), a
cross-sectioned release cap (120), and a bit (104). The assembly is
identical to that described for FIG. 9 above. The release cap (120)
mounts over the locking spring (102) and snaps into the groove
(112) on the split-collet nut (101) via internal lip (111). The
tang (121) on the locking spring (102) rides in one of the multiple
grooves (122) in the top of the release cap (120). The ramped
surfaces (123) on the release cap (120) and the cuts (124) in the
split-collet nut (101) cause the cap to rotate counter-clockwise
when the cap is pushed axially inward toward the split-collet nut.
The counter-clockwise rotation, in turn, forces the locking spring
(102) to open, allowing the bit (104) to be inserted or removed
without the need to rotate it.
[0044] The embodiment shown in FIG. 11 includes a collet nut (130),
a locking spring (131), an existing split-collet (132), and a bit
(133). The split-collet nut (130) is constructed with two internal
threaded regions; a right handed thread (134) which matches the
machine shaft and a smaller left handed thread (135) that matches
the outside diameter of the small end of the taper wound locking
spring (131). The locking spring (131) is taper wound in the left
hand direction. The spring's small end is fully threaded into the
split-collet nut (130). The split-collet nut (130) screws onto the
shaft of the machine being used. Once seated, the split-collet nut
constrains the locking spring and allows the above spring locking
phenomenon to occur. The bit (133) is inserted into the chuck by
lightly pushing it into the split collet (132) while simultaneously
rotating it counter-clockwise.
[0045] This spring-lock phenomenon can also be used as a one-way
shaft clamp or torque coupler configured as in FIG. 11 or as in
FIG. 12.
[0046] The shaft clamp embodiment shown in FIG. 12 includes a shaft
nut (140), a locking spring (141), and a shaft (142). The locking
spring (141) is wound into the shaft nut (140) and is retained by
the internal thread (143). The torque on the shaft is grounded by
the tang (144) on the locking spring (141) that is snapped into the
groove (145) on the shaft nut. The nut is inserted onto the shaft
(142) by lightly pushing it in while at the same time rotating it
in the direction opposite of the spring wind.
[0047] Embodiments of the present invention may incorporate a
variety of interfaces for shaft attachment including a hollow shaft
with the spring wound into it coupled to the outside diameter of a
second shaft. Embodiments may also be made to lock in either
rotational direction by varying the spring direction.
[0048] Devices in accordance with embodiments of the present
invention may be designed using any number of actuating spring
configurations. Such devices may incorporate a variety of
interfaces for shaft attachment. Such devices may employ any number
of different positive locking mechanisms, both passive and/or
active. Such devices may use other geometries for torque grounding,
bit alignment, and bit capture. The configuration may be altered to
adapt to any number of rotary machines of all makes and models. The
locking balls may be replaced by pins or wire forms that run in
straight, angled, or other slot geometries.
[0049] While the present invention has been described with respect
to a limited number of embodiments, those skilled in the art will
appreciate numerous modifications and variations therefrom. It is
intended that the appended claims cover all such modifications and
variations as fall within the true spirit and scope of this present
invention.
* * * * *