Information
-
Patent Grant
-
6311787
-
Patent Number
6,311,787
-
Date Filed
Tuesday, April 18, 200024 years ago
-
Date Issued
Tuesday, November 6, 200122 years ago
-
Inventors
-
Original Assignees
-
Examiners
Agents
-
CPC
-
US Classifications
Field of Search
US
- 173 176
- 173 178
- 173 216
- 173 217
- 173 181
- 173 935
- 081 571
- 081 5711
- 081 5714
- 081 5731
- 081 591
- 081 474
- 081 469
- 192 2232
- 192 41 R
- 192 4 LI
-
International Classifications
-
Abstract
A drill 30 for driving a bit 44 into a workpiece 50 includes an assembled anvil 58 and spindle 38, which are mounted for rotation together and for axial movement together within a drill housing 32. A planet carrier 56 is driven by a motor 52 and, in turn rotatingly drives the anvil 58 and the spindle 38. A chuck 42 is attached to a forward end of the spindle 58 for rotation and axial movement therewith. A plurality of rollers 162 are mounted in nests 182 of a roller cage 176, are maintained in parallel with an axis of the drill 30, and the anvil 58. The rollers 162, which are included in an automatic spindle lock 33, can be wedged between a fixed surface 74 of the drill housing 32 and a movable surface 102 of the anvil for automatically locking the spindle 38 with the housing. Following withdrawal of the bit 44 from the workpiece 50, an automatic brake 35 provides facility for braking the spindle 38. When the planet carrier 56 ceases to be driven, the anvil 58 and the spindle 38 are in a coasting mode relative to the slowing speed of the planet carrier 56. An automatic drag system 37 provides a drag between the coasting anvil 58 and the planet carrier 56 to bring the coasting speed of the anvil generally in line with the slowing speed of the planet carrier.
Description
BACKGROUND OF THE INVENTION
This invention relates to a power driven rotary device, and particularly relates to a power driven rotary tool with spindle lock, brake and drag systems.
Power driven rotary devices drive a variety of different tools or bits for performing various work-related operations on a workpiece. For example, such devices are used to drill a hole, driving a threaded member, form and shape portions of a workpiece, and the like. Typically, a power-operated rotary tool or device includes a power driver and transmission, a spindle rotated by the power driver, and a bit-holder, such as a chuck, mounted onto a forward end of the spindle. When the tool is to be used, a tool bit, such as a drill bit, is mounted in the chuck with a working end of the tool bit extending outward from the chuck at a working end of the tool. The spindle, the chuck and the drill bit are rotated by the power driver, while the working end of the drill bit is being urged into the workpiece.
The chuck may include several clamping jaws which are radially and axially movable along paths within the chuck to converge clamping surfaces of the jaws into a clamping position about portions of a shank of the drill bit which has been positioned in axial alignment within the chuck.
In one type of chuck, referred to as a keyless chuck, an outer ring of the chuck can be rotated by the user to move the jaws and thereby clamp, or unclamp, the drill bit relative to the chuck. In using a keyless chuck, the main body of the chuck must be prevented from rotating while the ring is rotated by the user to effect the desired operation of the jaws. With the chuck mounted to the spindle of the tool, any attempt to rotate the ring of the chuck while holding the chuck body to prevent rotation of the body is a difficult task.
To assist the user of the tool in rotating the ring of a keyless chuck, while precluding any rotation of the chuck body, an automatic spindle lock was developed many years ago, an example of which is described and illustrated in U.S. Pat. No. 3,243,023, which issued on Mar. 29, 1966.
The automatic spindle lock includes several wedging rollers which are contained within a housing of the tool to facilitate the locking of the spindle, and thereby the chuck body, to the housing at any time when operating power is not being applied to the tool. This will assist the operator in adjusting the jaws of the chuck in the process of clamping, or unclamping, any bit with respect to the chuck.
The wedging rollers are each formed with an axis which, desirably, should be parallel with an axis of the spindle, and is spaced from the other rollers in a circular path about the spindle axis. Each of the rollers is located within a respective chamber which allows the rollers to be moved desirably laterally of the axis thereof within the circular path, resulting in a slight lost motion between the rollers and the spindle. Also, the rollers are allowed to move in a radial direction relative to the spindle axis, while desirably maintaining the parallel relationship with the spindle axis. Each chamber includes interfacing, radially spaced boundaries formed by a radially outboard fixed surface which is associated with the housing, and by an inboard surface which is associated with the spindle.
The rollers are mounted for passive movement in the circular path when power is being applied to the tool to rotate the spindle and the chuck in a rotational mode. When power is not being applied to the tool, the spindle and the chuck are not rotating and are in a non-rotational mode.
If, during the non-rotational mode, the operator desires to clamp, or unclamp, the bit with respect to the chuck, the operator holds the housing with one hand, and slightly turns the chuck in either direction whereby the rollers become wedged between the fixed surface of the housing and the inboard surface of the spindle to effectively and automatically lock the spindle and the chuck with the housing. While continuing to hold the housing with the one hand, the operator turns the ring on the keyless chuck to facilitate clamping, or unclamping, movement of the jaws thereof, to allow the bit to be retained with, or be removable from, the chuck.
While it is desirable that the axes of the rollers be maintained in parallel with the spindle axis as noted above, the rollers are occasionally skewed from the axial alignment due to the limited freedom of movement of the rollers within their respective chambers. Consequently, some portions of the skewed rollers may not be not fully wedged in place when the operator adjusts the chuck to effect the automatic locking of the spindle with the housing, thereby lowering the integrity of such automatic locking.
In view of this deficiency, there is a need for a facility for insuring that, in the automatic locking of the spindle to the housing, each roller is wedged fully in place, with the axis thereof being in parallel with the spindle axis, to obtain the maximum automatic locking possible.
When the tool is in operation, and the operating power is removed therefrom, the power driver begins to coast to a stop and, after a brief down-coasting period, eventually ceases to rotate. Due to the built-in lost motion noted above, the spindle tends to continue to rotate for a brief period at or near the normal operational speed, which is faster than the down-coasting speed of the power driver.
During the brief down-coasting period, the faster spindle moves slightly ahead of the slowing power driver to the extent that the wedging rollers become wedged whereafter a reactive force, resulting from an impact engagement of the faster spindle and the slowing power driver, causes the rollers to become unwedged. This condition can occur several times during the down-coasting period where the rollers may skew as noted above, and where the facing portions of the power driver, spindle and rollers repeatedly and engagingly interact to develop an undesirable chattering noise.
Therefore, there is a further need for a facility for reducing or eliminating the conditions which lead to the undesirable chattering noise, to thereby reduce or eliminate such noise.
SUMMARY OF THE INVENTION
It is, therefore, an object of the invention to provide a rotary tool having an automatic spindle lock with facility for obtaining a high integrity locking of a spindle of the tool to a housing of the tool.
Another object of this invention is to provide a rotary tool having an automatic brake and/or an automatic drag system with facility for reducing or eliminating conditions which lead to any undesirable chattering noise, to thereby reduce or eliminate such noise, either alone or in combination with the automatic spindle lock.
With these and other objects in mind, this invention contemplates a power driven rotary device, which includes a housing having at least one fixed wedging surface, a drive carrier mounted for rotation within the housing, a powered driver located within the housing for rotating the drive carrier, a drivable output member formed with an axis and located within the housing and mounted therein for rotation. The drivable output member includes at least one movable wedging surface located in spatially facing relation to the fixed wedging surface, and the drive carrier rotates the drivable output member upon rotation of the drive carrier. At least one wedging element is formed with an axis and is located for free movement between the fixed wedging surface and the at least one movable wedging surface for movement with the drive carrier and the drivable output member when the drive carrier and the drivable output member are rotating at substantially the same speed. The at least one wedging element can also be wedged between the fixed wedging surface and the at least one movable wedging surface in a wedging mode when the drivable output member is rotating at a speed different from the speed of the drive carrier to lock the drivable output member with the housing. Means are provided for maintaining the axis of the at least one wedging element in a prescribed orientation relative to the axis of the drivable output member.
This invention further contemplates A power driven rotary device, which includes a housing, a drive carrier mounted for rotation within the housing, a powered driver located within the housing for rotating the drive carrier, and a drivable output member having at least portions located within the housing and mounted therein for rotation. The drive carrier is movable into engagement with, and for rotating, the drivable output member upon rotation of the drive carrier. A drag surface is located on at least a portion of the drivable output member which is in engagement with an adjacent portion of the drive carrier to present a drag on the rotational movement of the drivable output member when the speed of the drivable output member is different from the speed of the drive carrier.
Additionally, this invention contemplates a power driven rotary device, which a housing, a drive carrier mounted for rotation within the housing, a powered driver located within the housing for rotating the drive carrier, and a drivable output member having at least portions located within the housing and mounted therein for rotation. The drive carrier is movable into engagement with, and for rotating, the drivable output member upon rotation of the drive carrier. Means responsive to the drivable output member being in an unloaded mode is provided for applying a braking force to the drivable output member, and means responsive to the drivable output member being in a loaded mode is provided for removing the braking force from the drivable output member.
Other objects, features and advantages of the present invention will become more fully apparent from the following detailed description of the preferred embodiment, the appended claims and the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
In the accompanying drawings:
FIG. 1
is a sectional side view of a tool showing an automatic spindle lock, an automatic brake and an automatic drag system, all in accordance with certain principles of the invention;
FIG. 2
is a partial and enlarged view of a portion of
FIG. 1
showing details of the automatic spindle lock, brake and drag systems, in accordance with certain principles of the invention;
FIG. 3
is a perspective view showing details of a first section of a first embodiment of a two-section anvil of the tool of
FIG. 1
, in accordance with certain principles of the invention;
FIG. 4
is a sectional view showing other details of the first section of the anvil of
FIG. 3
, in accordance with certain principles of the invention;
FIG. 5
is a perspective view showing details of a second section of the anvil of the tool of
FIG. 1
, in accordance with certain principles of the invention;
FIG. 6
is an end view showing still further details of the first section of the anvil of
FIG. 3
, in accordance with certain principles of the invention; and
FIG. 7
is an end view showing additional details of the second section of the anvil of
FIG. 5
, in accordance with certain principles of the invention; and
FIG. 8
is a perspective view showing details of a first section of a second embodiment of an anvil, in accordance with certain principles of the invention;
FIG. 9
is an exploded perspective view showing a roller cage, rollers and a fixed ring of the automatic lock system of
FIG. 1
, in accordance with certain principles of the invention;
FIG. 10
is a perspective view showing the rollers and roller cage of
FIG. 9
in assembly and spaced from the fixed ring, in accordance with certain principles of the invention;
FIG. 11
is a perspective view showing the roller cage, rollers and the fixed ring of
FIG. 9
in full assembly, in accordance with certain principles of the invention;
FIG. 12
is an end view showing the roller cage, rollers and fixed ring of
FIG. 9
in assembly with drive fingers, shown in section, of a planet carrier of the tool of
FIG. 1
, all in a free position, in accordance with certain principles of the invention;
FIG. 13
is an end view showing the assembled roller cage, rollers, fixed ring and drive fingers, shown in section, of
FIG. 12
, in a motor-engaged position, in accordance with certain principles of the invention;
FIG. 14
is an end view showing the assembled roller cage, rollers, fixed ring and drive fingers, shown in section, of
FIG. 12
, in a spindle-locked position, in accordance with certain principles of the invention;
FIG. 15
is a perspective view showing a second embodiment of an automatic spindle lock, in accordance with certain principles of the invention;
FIG. 16
is a partial and enlarged view, similar to
FIG. 2
, showing the automatic brake system in a brake-release condition, in accordance with certain principles of the invention;
FIG. 17
is a perspective view showing a brake collar of the automatic brake system of
FIGS. 1
,
2
and
16
, in accordance with certain principles of the invention
FIG. 18
is a perspective view showing a brake disk of the automatic brake system of
FIGS. 1
,
2
and
16
, in accordance with certain principles of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT OF THE INVENTION
As shown in
FIG. 1
, one embodiment of a power driven rotary device could be, for example, a tool such as that illustrated as a drill
30
. The drill
30
includes a housing
32
composed of two clam-shell sections
34
, one of which has been removed to reveal the internal elements of the drill, including an automatic spindle lock
33
, an automatic brake
35
and an automatic drag system
37
. Referring to
FIGS. 1 and 2
, a forward or working end
36
of an output member, such as, for example, a spindle
38
, extends along an axis of the spindle, forward and outward through an axial opening
39
of a forward nosepiece
40
of the drill
30
and has a bit holder, such as a chuck
42
, attached thereto for rotation and axial movement therewith. A working element, such as, for example, a drill bit
44
, is formed with a shank
46
which is held within the chuck, and a forward or working end
48
formed, for example, with a drilling profile, which is positioned for forming or drilling a hole in a workpiece
50
. The drill bit
44
can be held with the chuck
42
, for example, by adjustable jaws
51
of the chuck, which are selectively clamped about the shank
46
of the bit.
The power driven rotary device could be tools other than the drill
30
without departing from the spirit and scope of the invention. For example, the tool could be a screwdriver, a router bit driver, or any rotary driver which rotates a working element.
A powered driver, such as a motor
52
, is mounted within the housing
32
, and is drivingly coupled to the spindle
38
, through a gear transmission
54
, a drive carrier, such as, for example, a first embodiment of a planet carrier
56
, and a drivable output member, which includes a coupler, such as, for example, a first embodiment of an anvil
58
. The anvil
58
is axially positioned about and attached to the spindle
38
for rotational and axial movement therewith, which could also be included as an element of the drivable output member. A bushing
60
and an axially spaced bearing
62
are fixedly assembled within a skeleton frame
64
, which is an integral part of the interior of the housing
32
, and provide an axial mount for rotation of the spindle
38
. The bushing and the bearing
62
also serve as a pair of spaced supports for supporting the anvil
58
and the spindle
38
for axial movement relative thereto.
As shown in
FIG. 1
, a power compartment
66
is formed in a lower handle portion of the housing
32
for receipt of an electrical battery (not shown), through an opening at the base of the handle portion, to provide a cordless source of operating power for the motor
52
. A switch
68
is mounted in an upper handle portion of the housing
32
, and is controllable by a conventional trigger element
70
to facilitate control of the switch by an operator, to thereby supply operating power to, or remove such power from, the motor
52
.
It is noted that the drill
30
could also be powered from a corded source of operating power without departing from the spirit and scope of the invention.
Referring to
FIG. 2
, a band-like ring
72
(
FIG. 12
) is located about, and in axial alignment with, the axis of the spindle
38
and is fixedly attached within the housing
32
by being press fit into a nest formed by the interior skeleton frame
64
of the housing. The ring
72
forms an inner, circular surface
74
which is non-rotatable and is located about, and faces, the common axis of the spindle and the drill
30
. At least portions of the ring inner surface
74
form a fixed wedging surface of the housing during a wedging mode. The ring
72
is also shown in
FIGS. 9 through 14
.
The anvil
58
is formed by two elements, a metal element
76
and a compliant element
78
, which could be composed of rubber or any other suitable compliant material. As shown in
FIG. 6
, the metal element
76
of the anvil
58
is formed with a central axial opening
80
having a pair of spaced interfacing flat surfaces
82
and
84
, and a pair of spaced interfacing concave surfaces
86
and
88
. As shown in
FIG. 7
, the compliant element
78
of the anvil
58
is formed with a central axial opening
90
having a pair of spaced interfacing flat surfaces
92
and
94
, and a pair of spaced interfacing concave surfaces
96
and
98
. When the elements
76
and
78
are joined to form the anvil
58
, an axial opening is formed through the anvil which has the profile of openings
80
and
90
, and which fits axially about a complementary peripheral surface portion
100
of the spindle
38
as illustrated in FIG.
2
.
As shown in
FIGS. 3 and 6
, the metal element
76
is formed with five spaced flat surfaces
102
on the outer periphery thereof, portions of each of which form a movable wedging surface during the wedging mode. Five concave drive-finger receptor surfaces
104
are formed on the outer periphery of the metal element
76
and extend between adjacent respective pairs of the flat surfaces
102
. Five lugs
106
are formed on an inboard end of the metal element
76
and extend in an axial direction from the portions of the metal element which are common to respective ones of five flat surfaces
102
.
Four spaces
108
of generally common width, shape and depth are formed between adjacent respective pairs of the lugs
106
, while a fifth space
110
of smaller width is formed between a respective adjacent pair of the lugs
106
. Each of the spaces
108
and
110
is formed with an outer edge
112
which is contiguous with a respective one of the concave receptor surfaces
104
, and a lower edge
114
which is contiguous with the opening
80
. Also, each of the spaces
108
and
110
are formed with spaced sidewalls
116
which taper toward each other as the sidewalls extend from the outer edge
112
to the lower edge
114
. As shown in
FIGS. 3 and 4
, an annular groove
118
is formed in the outer peripheral surface of the metal element
76
near an outboard end thereof for eventual receipt of a band such as, for example, a compliant O-ring
119
, as illustrated in
FIGS. 2 and 16
, which could be composed of rubber or any other suitable compliant material.
As shown in
FIGS. 5 and 7
, the compliant element
78
is formed on an inboard end thereof with four spaced lugs
120
of generally common width, shape and height in an axial direction, and a fifth lug
122
of smaller width. Five spaces
124
are formed between adjacent respective pairs of the lugs
120
and
122
. The compliant element
78
is formed with a circular peripheral surface
126
which extends axially to form circular outer surfaces
128
, referred to as drag surfaces, of the lugs
120
and
122
.
In the formation of the anvil
58
, the inboard ends of the metal element
76
and the compliant element
78
are assembled in interfacing engagement. In this manner, the four lugs
120
of the compliant element
78
are inserted into the four spaces
108
of the metal element
76
, and the fifth lug
122
of the compliant element is inserted into the fifth space
110
of the metal element. Also, the lugs
106
of the metal element
76
are inserted into the spaces
124
of the compliant element
78
. When the assembly of the metal element
76
and the compliant element
78
has been completed, the outer surfaces of the lugs
106
,
120
and
122
are fully and snugly seated within the respective spaces
124
,
108
and
110
, with all interfacing surfaces being in engagement. In this manner, the anvil
58
presents an integral and unitary structural appearance, a portion of which is metal and a portion of which is compliant.
By facility of the smaller widths of the space
110
and the lug
122
, the inboard ends of the metal element
76
and the compliant element
78
can only be assembled in a single orientation, which insures that the metal element
76
and the compliant element
78
are always properly aligned and assembled in the formation of the anvil
58
.
It is noted that when the metal element
76
and the compliant element
78
are assembled, radially outward portions
120
a
and
122
a
of the lugs
120
and
122
, respectively, will be radially outward from the concave receptor surfaces
104
, and will form, in effect, end walls of radially inward chambers, the base or floor of which are formed by the receptor surfaces. With this arrangement, the circular outer surfaces
128
, or drag surfaces, of the lugs
120
and
122
will be located radially outward from the concave receptor surfaces
104
.
As shown in
FIG. 15
, another drive carrier, such as a second embodiment of a planet carrier
129
, is formed by a circular plate
130
with a central opening
132
, and a plurality of spaced, transmission-coupling pins
134
assembled within spaced respective openings
136
formed in the plate in a circular path about an axis of the opening. The pins
134
extend from a first major face
138
of the plate
130
in an axial direction toward the motor
52
(FIG.
1
), and are coupled to the transmission
54
(
FIG. 1
) for the coupling of rotary driving power from the motor to the planet carrier
129
. The second-embodiment planet carrier
129
is also formed with three drive fingers
140
, which extend from a second major surface
142
of the plate
130
in an axial direction opposite the axial direction of the pins
134
.
The structure of the first-embodiment planet carrier
56
is similar to the structure of the second-embodiment planet carrier
129
, except that the first-embodiment planet carrier is formed with five drive fingers
162
(FIGS.
2
and
12
), instead of the three drive fingers
140
(
FIG. 15
) of the carrier
129
. Also, the cross-sectional structure of the five drive fingers
162
of the first-embodiment planet carrier
56
is different from that of the three fingers
140
of the second-embodiment planet carrier
129
.
For example, as shown in
FIG. 15
, the three drive fingers
140
are each formed with a slightly concave surface
164
which faces the axis of the planet carrier
129
, and a convex surface
166
spaced radially outward from the concave surface. A pair of flat spaced side surfaces
168
extend between the concave and convex surfaces
164
and
166
, and diverge as the side surfaces extend in a direction outward from the axis of the planet carrier
129
.
On the other hand, as shown in
FIGS. 12
,
13
and
14
, each of the five fingers
162
of the first embodiment planet carrier
56
is formed with a radially inward-facing first convex surface
170
, and a radially outward-facing second convex surface
172
. Also, as shown in
FIGS. 12
,
13
and
14
, the convexity of the portions of the convex surface
170
of each of the fingers
162
, which nest in the concave receptor surfaces
104
of the anvil
58
, nearly complement the concavity of the receptor surfaces to facilitate the general seating of selected portions of the convex surface
170
within three selected portions of the receptor surfaces when the fingers are in respective
In
FIGS. 2 and 16
, the elements of the first embodiment planet carrier
56
, which are similar to the corresponding elements of the second embodiment planet carrier
129
, are numbered with the same numbers, but with the letter “a” following thereafter. For example, in
FIGS. 2 and 16
, the circular plate of the first embodiment planet carrier
56
is identified by the alpha-numeric combination of “
130
a.”
Referring to
FIG. 9
, five rollers
174
form a plurality of wedging elements, each extending along a wedging-element axis thereof, which facilitate the automatic locking of the spindle
38
with the housing
32
. A roller cage
176
is formed by a support member, such as ,for example, a flat ring
178
having a central opening
180
formed about an axis of the ring. Five nests
182
of the roller cage
176
are each formed by (1) a respective ear
184
formed with, and extending inward from an inner side wall of, the ring
178
in the plane thereof, and (2) a pair of parallel spaced fingers
186
which are joined with, and extend in a common axial direction from opposite sides of, the respective ear. The parallel fingers
186
of each pair of fingers are located equally on opposite sides of a respective radial centerline
187
, as illustrated in
FIG. 9
with respect to one of the five pairs, and are not aligned radially with the axis of the ring
178
. This off-radial alignment of the fingers
186
facilitates the support of each of the rollers
174
such that at least one of a plurality of sets of an inner peripheral surface
190
and an outer peripheral surface
192
(FIG.
9
), which are located on diametrically opposite sides of the roller, and which extend axially between opposite ends of the roller, are in radial alignment with the axis of the ring
178
.
While each roller
174
is pinched between its respective pair of fingers
186
, as shown in
FIG. 10
, each roller may rotate about its axis, during operation of the drill
30
, and during operation of the automatic spindle lock
33
, when the roller is being moved between the various positions shown in
FIGS. 12
,
13
and
14
. During such movement of the rollers
174
, a different set of two diametrically-opposed peripheral surfaces
190
and
192
of each roller will be radially aligned with the axis of the ring
178
.
As shown in
FIG. 10
, the rollers
174
are inserted into respective ones of the nests
182
such that one end of each roller seats against an inside surface
188
of the ear
184
, and the peripheral surfaces of the rollers are pinch-gripped between the parallel fingers
186
, as noted above. In this manner, the rollers
174
are held in a prescribed orientation where the axes of the five rollers are maintained in a parallel relation with each other, and with the axis of the ring
178
, and ultimately the axis of the anvil
58
. Also, the inner peripheral surface
190
of each of the rollers
174
which faces the axis of the ring
178
, and the outer peripheral surface
192
of each of the rollers which faces away from the axis of the ring, is fully exposed, between opposite ends thereof, and unencumbered by the fingers
186
of the nests
182
.
Thus, the roller cage
176
and the nests
182
form a means for maintaining the axis of each of the rollers
174
in the prescribed orientation, that is, parallel, relative to the axis of the anvil
58
, and to the axes of the other rollers. In addition, each of the fingers
186
forms a blocking member which precludes transaxial movement of the respective rollers
174
in the direction of the blocking member.
As shown in
FIGS. 2
,
9
,
10
and
11
, the ring
72
is formed with a ledge
194
which is positioned for receipt of the flat ring
178
of the roller cage
176
. Also, the ring
72
is formed with six spaced shoulders
195
which are contiguous with the ledge
194
, and which face radially inward of the ring. Referring to
FIG. 11
, the roller cage
176
is in assembly with the ring
72
such that the flat ring
178
of the roller cage is in interfacing engagement with the ledge
194
of the ring
72
, the nested rollers
174
are located within the ring
72
, and the outer side surface
192
(
FIG. 10
) of each roller is fully in an interfacing position with the inner circular surface
74
of the ring
72
, but slightly spaced therefrom. Also, the roller cage
176
is assembled with the ring
72
for independent rotational movement relative to the ring, and will remain in this condition when all elements of the drill
30
have been assembled within the housing
32
.
As shown in
FIG. 18
, and with regard to the automatic brake
35
, a brake disk
196
, having a relatively thin axial thickness, is formed with a flat, circular washer-like plate
198
. A pair of diametrically-opposed ears
200
are formed on opposite sides of the plate
198
, and extend in a common axial direction. The plate
198
is further formed with a central opening
202
and a brake surface
204
. As shown in
FIG. 17
, a brake collar
206
is formed with an axial thickness greater than the axial thickness of the plate
198
, and with a central opening
208
. A circular ring-like brake pad
210
extends from an end face
212
of the brake collar
206
and is formed with a brake surface
214
which ultimately interfaces with the brake surface
204
of the brake disk
196
.
Referring to
FIGS. 2 and 16
, the spindle
38
is formed with an annular limiting collar
216
for eventual engagement with one end of a compression spring
218
, with the opposite end of the spring eventually being positioned for engagement with the bearing
62
. The bushing
60
, the bearing
62
, the ring
72
and the ears
200
of the brake disk
196
, are all fixedly assembled with the frame
64
internally of the housing
32
, by positioning the ears
200
in a pair of diametrically opposed slots
219
formed in the housing frame. The spindle
38
is mounted in the bushing
60
and the bearing
62
for axial and rotational movement relative thereto.
The brake collar
206
is fixedly assembled on the spindle
38
for axial and rotational movement therewith, while the spring
218
is positioned about the spindle and is captured between a fixed location within the housing
32
, i.e., a forward side of the bearing
62
, and the annular limiting collar
216
which is formed on the spindle. The spindle
38
is normally urged axially forward, in the direction of the arrow illustrated on the working end
36
thereof, by the biasing force of the expanding spring
218
against the annular collar
216
. As the spindle
38
is normally urged in the forward direction, the brake surface
214
of the brake collar
206
is urged into engagement with the brake surface
204
of the brake disk
196
for the application of a braking force in opposition to the rotation of the spindle. Also, the engagement of the brake surface
214
with the brake surface
204
precludes any further movement of the spindle
38
in the forward direction. Even though the engagement between the brake disk
196
and the brake collar
206
limits the forward axial movement of the spindle
38
, a rear end
221
of the chuck
42
serves as a stop which is positioned in the path of movement of the limiting collar
216
to limit the distance the drivable output member can be urged in the forward direction.
Referring to
FIG. 1
, when the working end
48
of the drill bit
44
has a back force applied thereto, for example, when the working end is pressed against the workpiece
50
, the spindle
38
is moved rearward, as illustrated in
FIG. 16
, in the direction of the arrow on the working end
36
of the spindle. As further shown in
FIG. 16
, as the spindle
38
is moved rearward, the brake collar
206
is moved away from the brake disk
196
to allow the spindle
38
and the drill bit
44
to be rotated, unencumbered by engagement of the brake collar with the brake disk. Also, as the spindle
38
is moved rearward, the annular collar
216
is allowed to move into the larger opening
39
of the nosepiece
40
. With the rearward movement of the annular collar
216
, the spring
218
is compressed and loaded essentially fully for eventually providing the biasing force necessary to move the spindle
38
in the forward direction when the back force is removed from the drill bit
44
.
The automatic brake
35
of the drill
30
is includes (1) the spring
218
, as captured between the bearing
62
, which is fixed to the housing
32
, and the annular collar
216
on the spindle
38
, (2) the brake disk
196
, which is fixed to the housing, (3) the brake collar
206
, which is fixed to the spindle
38
, and (4) the spindle being mounted in the fixed bushing
60
and the fixed bearing for forward and rearward axial movement relative to the bushing and the bearing. A means responsive to the anvil
58
and the spindle
38
being driven in an unloaded rotational mode for applying a braking force to the anvil and the spindle includes the bearing
62
, the brake disk
196
, the brake collar
206
, the annular collar
216
and the spring
218
. A means responsive to the anvil
58
and the spindle
38
being driven in a loaded rotational mode for removing the brake force from the anvil and the spindle includes the axial movability of the spindle and the attachment of the brake collar thereto.
At the rearward end of the spindle
38
, the anvil
58
is press fit onto the spindle, as illustrated in
FIG. 2
, and the assembly (
FIG. 11
) of the rollers
174
, the roller cage
176
and the ring
72
is moved into position where the ring
72
is press fit into the internal frame
64
of the housing
32
. At the same time, each of the rollers
174
assumes a position in engagement with a respective one of the flat surfaces
152
of the anvil
58
, and between the respective flat surface and the inner circular surface
74
of the ring
72
. In this position, each roller
174
is in engagement with the respective flat surface
152
of the anvil
58
, but is normally spaced slightly from the inner circular surface
74
of the ring
72
, except during a “spindle locking” or wedging mode as described below. This arrangement allows limited free movement of the rollers
174
, radially between the inner circular surface
74
of the ring
72
and the respective flat surfaces
152
of the anvil
58
during a non-wedging mode. Also, the rollers
174
are desirably positioned such that the axis of each roller is parallel with the axes of the remaining rollers and with the axis of the anvil
58
, and thereby with the axis of the spindle
38
. The parallel positioning of the rollers
174
, as described, is maintained by the parallel arrangement of each pair of fingers
186
.
The planet carrier
56
is positioned about the anvil
58
such that each of the five drive fingers
162
is located in a respective one of the five drive-finger receptor surfaces
104
(
FIG. 12
) of the anvil. In the assembled position, the rollers
174
are located within a space
163
(
FIG. 13
) between each adjacent pair of the drive fingers
162
, with the space being sufficiently wide in a circular path, about the axis of the anvil
58
, to allow limited free movement of the rollers in the circular path between the adjacent pairs of drive fingers
162
. Since the ring
178
of the roller cage
176
is mounted for free movement relative to the ledge
174
of the fixed ring
72
, the roller cage does not encumber the limited free movement of the rollers
174
in the circular path between adjacent drive fingers
162
. As shown in
FIG. 1
, and as noted above, the planet carrier
56
is coupled to the motor
52
through the transmission
54
.
The automatic spindle lock
33
of the drill
30
includes (1) the anvil
58
mounted on the spindle
38
for rotation therewith, (2) the flat surfaces
152
formed on the anvil and the receptor surfaces
104
formed on the periphery of the anvil, (3) the inner circular surface
74
of the ring
72
fixedly mounted to the housing
32
, (4) the rollers
174
and (5) the roller cage
176
with each pair of parallel spaced fingers
186
.
Referring to
FIG. 12
, during a period when the drill
30
is not in use, and is not being manipulated to operate the automatic spindle lock, the elements of the drill assume a “free” mode position, which is a first of three mode positions assumed by the fingers
162
. The second and third mode positions are the above-noted “spindle lock” mode position and a “motor engaged” mode position, respectively. In the free mode position, the drive fingers
162
are located such that a central portion of the convex surface
170
of each drive finger is centrally radially positioned within the respective receptor surface
104
of the anvil
58
. Also in the free mode position, the roller cage
176
is positioned with respect to the anvil
58
such that the rollers
174
are located in the middle of the respective flat surface
152
of the anvil, generally equally between spaced adjacent drive fingers
162
, which are also spaced slightly from adjacent arms
186
of the roller cage.
Assume now that the operator wishes to mount the bit
44
(
FIG. 1
) in the chuck
42
, in preparation for a drilling operation. The user holds the housing
32
of the unoperated drill
30
in one hand and, with the other hand, turns the chuck
42
slightly in either rotary direction about the axis of the chuck. Since the chuck
42
is mounted on the spindle
38
, and the anvil
58
is also mounted on the spindle, the anvil will also turn slightly when the user turns the chuck slightly. As noted above, the rollers
174
are mounted for limited free movement in the circular path within the space
163
. When the chuck
42
is turned slightly, each of the rollers
174
is slightly relocated from its free mode position (FIG.
12
), on the respective flat surface
152
of the anvil
58
, to a position near one end of the respective flat surface, as shown in
FIG. 14
, whereby the drill
30
is placed in a wedged mode.
In this relocated, wedged-mode position, each roller
174
becomes wedged between the respective flat surface
152
of the anvil
58
, referred to as the movable wedging surface, and the adjacent portion of the inner circular surface
74
of the fixed ring
72
, referred to as the fixed wedging surface. The wedging of the rollers
174
in this manner automatically locks the spindle
38
with the housing
32
in the “spindle locked” mode position (FIG.
14
), to preclude rotational movement of the chuck
42
relative to the housing.
Thereafter, the operator inserts the shank
46
of the bit
44
into the bit-receiving opening of the chuck, and manipulates the jaw-positioning facility of the chuck to position the jaws
51
in a clamping position about the shank as shown in FIG.
1
. During normal use of the drill
30
, the operator presses the bit
44
into the workpiece
50
whereby the automatic brake
35
, if included in the drill
30
, is released by moving the brake collar
206
away from the brake disk
196
, as shown in FIG.
16
. The operator then depresses the trigger
70
to operate the motor
52
, resulting ultimately in the rotation of the chuck
42
and the bit
44
, whereafter the operator urges the rotating bit into the workpiece
50
.
During operation of the drill
30
, the planet carrier
56
and the drive fingers
162
are being rotated in a given direction, such as, for example, counterclockwise as indicated by the arrow in FIG.
13
. The relative position between the drive fingers
162
and the respective concave receptor surfaces
104
, in
FIG. 13
, represent the motor engaged mode position thereof. While each drive finger
162
functions in the same manner as the other four drive fingers, in the immediately following portion of the description, reference will be made primarily to an adjacent pair of the drive fingers
162
a
and
162
b
to describe the relationship between the fingers and other elements of the drill
30
.
In the direction of rotation illustrated in
FIG. 13
, one drive finger, such as, for example, the drive finger
162
a
, will be referred to as the leading drive finger, and an adjacent drive finger, such as, for example, the drive finger
162
b
, will be referred to as the trailing drive finger. Each of the nests
182
of the roller cage
176
, such as, for example, the nest
182
a
, is located within a respective one of the spaces
163
, for limited free movement, as noted above, between the leading finger
162
a
and the trailing finger
162
b.
Referring further to
FIG. 13
, when the drill
30
is being used in the manner described above, a forward section
165
of each of the fingers
162
of the planet carrier
56
, such as, for example, the finger
162
b
, is moved to a forward portion of the respective receptor surface
104
of the anvil
58
, where the fingers collectively apply a driving force to the anvil. The locating of the forward section
165
of each of the fingers
162
represents the “motor engaged” mode position (FIG.
13
).
In addition to engaging a forward portion of each receptor surface
104
, the forward section
165
of each of the trailing fingers
162
, for example, the finger
162
b
, engages an adjacent finger, for example, the finger
186
a
, of one of the nests
182
, for example, the nest
182
a
, to simultaneously and collectively apply a driving force to the roller cage
176
. In this manner, the anvil
58
and the roller cage
176
are driven together at the same rotational speed.
When the drilling operation is complete, the operator extracts the bit
44
from the workpiece
50
and releases the trigger
70
to thereby remove the operating power from the motor
52
, whereby the driving force is withdrawn from the planet carrier
56
and the drive fingers
162
. It is noted that prior to extracting the bit
44
from the workpiece
50
, the operator could operate the drill
30
in a reverse mode, and extract the bit during this mode.
In any event, when the trigger
70
is released, the rotational speed of the planet carrier
56
and the fingers
162
cease to be driven whereby the rotational speed thereof gradually decreases in a slowing mode. Since the anvil
58
is not attached to the drive fingers
162
, and because the circular distance of each of the spaces
163
allows for limited movement of the respective nests
182
, then the anvil, the spindle
38
, the chuck
42
and the bit
44
continue to coast, at a rotational speed greater than the slowing speed of the planet carrier
56
. During this period, the finger
186
b
of each of the nests
182
, for example, the nest
182
a
, eventually engages an adjacent trailing portion of the slowing respective leading drive finger, such as, for example, the finger
162
a
, whereby the nests are rebounded toward the trailing drive finger
162
b
. This rebounding action is repetitive and continues for a brief period, during which a chattering noise occurs and does not stop until rotation of the elements of the drill
30
have ceased.
If the roller cage
176
and the nests
182
were not present during the rebounding action, the rollers
174
could become skewed and lodged in a position, within the respective spaces
163
, which would be non-parallel with the axis of the anvil
58
, The skewed and lodged position of the rollers
174
could preclude eventual normal and effective operation of the automatic spindle lock
33
, which is necessary for the removal of the bit
44
. However, with the presence of the roller cage
176
and the nests
182
, the rollers
174
are allowed to encounter the above-noted repetitive bouncing action during the coasting of the anvil
58
, but will be maintained in parallel with the axis of the anvil during the coasting period. Thus, when the operator again operates the automatic spindle lock
33
as described above, the rollers
174
are in position to accomplish an effective and efficient operation of the lock.
If the drill
30
is equipped with the automatic brake
35
, the spindle
38
is braked in the manner described above. In the event there is any chattering noise occurring during the period when the rollers
174
are being bounced between the forward leg
162
a
and the trailing leg
162
b
, the operation of the automatic brake
33
will quickly stop the coasting of the spindle
38
and thereby effectively reduce the period during which the noise occurs.
It is noted that the automatic spindle lock
33
functions independently of the automatic brake
35
. Thus, the automatic spindle lock
33
maintains the parallel alignment of the rollers with the axis of the anvil
38
regardless of the presence, or absence, of the automatic brake
35
.
Referring to
FIGS. 2 and 16
, as noted above, the metal element
76
and the compliant element
78
are assembled to form the anvil
58
such that the circular outer surfaces
128
(
FIG. 5
) of the lugs
120
and
122
of the compliant element
78
extend radially outward beyond the radial location of the respective concave receptor surfaces
104
. With this arrangement, when the anvil
58
is assembled within the housing
32
, the circular outer surfaces
128
are located to engage portions of the convex surfaces
172
(
FIG. 12
) of the drive fingers
162
. When the motor
52
is operating, the planet carrier
56
is driving the anvil
58
and the roller cage
176
so that all elements are rotating at the same speed as described above. Therefore, there is no relative rotational movement between the outer surfaces
128
of the lugs
120
and
122
and the fingers
162
of the planet carrier
56
.
However, when operating power is removed from the motor
52
, the unpowered planet carrier
56
is rotating at the slowing speed which is less than the coasting speed of the anvil
58
, as described above. At this time, there is relative rotation between the outer surfaces
128
of the compliant lugs
120
and
122
, and adjacent portions of the fingers
162
of the slowing planet carrier
56
. This action results in the operation of the automatic drag system
37
whereby the movement of the compliant outer surfaces
128
relative to the fingers
162
applies a drag or resistance to the anvil
58
tending to slow the coasting anvil to a slowing speed somewhat consistent with that of the planet carrier
56
. In this context, the surfaces
128
serve as drag surfaces.
In addition, as shown in
FIGS. 2 and 16
, the compliant O-ring
119
is in engagement with the wall surface of the annular groove
118
and extends outward therefrom into engagement with the wall surface of the central opening
132
a
of the planet carrier
56
. Thus, the O-ring
119
provides a compliant intermediary between the planet carrier
56
and the anvil
58
. As long as the planet carrier
56
and the anvil
58
are rotating at the same speed, there is no relative rotation between the O-ring
119
and the wall surface of the central opening
132
a
. However, when operating power is removed from the motor
52
, the presence of the compliant O-ring
119
between the faster rotating anvil
58
and the slower rotating planet carrier
56
results in the application of a drag or resistance to the anvil
58
tending to slow the coasting anvil to a slowing speed somewhat consistent with that of the planet carrier
56
. In this context, the portions of the O-ring
119
, which engage the planet carrier
56
, also function as drag surfaces.
The automatic drag system
37
could include either (1) the compliant element
78
, being positioned for engagement with the fingers
162
, or (2) the compliant O-ring
119
being positioned in the annular groove
118
and in engagement with the wall surface central
132
a
of the planet carrier
56
, or (3) could include both (1) and (2) above.
Referring again to
FIG. 15
, in conjunction with the second embodiment planet carrier
129
, a second embodiment of an anvil
144
is shown with a central axial opening
146
having four axially aligned grooves
148
, with each groove being spaced from the two adjacent grooves by ninety degrees. Further, adjacent grooves
148
are joined by four respective curved surfaces
150
. The grooves
148
and the curved surfaces
150
extend axially between opposite ends of the anvil
144
.
The anvil
144
is formed with three flat surfaces
152
spaced equally about the periphery of the anvil, with each flat surface forming a movable wedging surface. The anvil
144
is also formed with three concave drive-finger receptor surfaces
154
, each of which is interspersed between adjacent pairs of the flat surfaces
152
. The three flat surfaces
152
, and the concave surfaces
154
, extend in an axial direction between opposite ends of the anvil
144
, and are each referred to as a movable wedging surface. It is noted that the anvil
144
could be formed with a central axial opening identical to the central axial opening
80
(
FIG. 6
) of the anvil
58
instead of the central axial opening
146
(
FIG. 12
) of the anvil
144
.
A second embodiment roller cage
220
is formed, for example, by casting or molding, with a circular band
222
and three integral pairs of cage fingers
224
. Each pair of fingers
224
are spaced to receive a respective one of three wedging rollers
226
therebetween. Adjacent pairs of the cage fingers
224
are spaced from each other for receipt of the drive fingers
140
therebetween.
The second embodiment elements, such as the planet carrier
129
, the anvil
144
, the roller cage
220
, the rollers
226
, a ring
228
, which is similar to the ring
72
(FIG.
12
), and a spindle
230
can be assembled in the housing
32
of the drill
30
, and function in the same manner as that described above with respect to the first embodiment elements.
Referring to
FIG. 8
, another embodiment of a metal anvil element
232
, for use as a component of the automatic drag system
33
, is formed with a central axial opening
234
having four spaced axially-directed ribs
236
which define a central opening structure similar to that of the central axial opening
146
(FIG.
15
). The ribs
236
extend axially outward from within the central opening
234
at one end
238
thereof. The periphery of the anvil
232
is formed with five spaced flat surfaces
240
and five spaced drive-finger concave receptor surfaces
242
. An annular ledge
244
is formed concentrically about the axis of the central opening
234
at the end
238
of the anvil element
232
, which is radially outward from the ribs
236
, but radially inward of the flat surfaces
240
and the receptor surfaces
242
. A compliant O-ring
246
, which could be composed of rubber or any suitable compliant material, is placed over the annular ledge
244
, and a metal ring
248
is press fit onto, or otherwise firmly secured about, the radially outward portions of the extended ends of the ribs
236
to form an axial element which is functionally similar to the metal element
76
with the compliant O-ring
119
. The compliant element
78
could be assembled with an end
250
of the anvil element
232
, opposite the end
238
, in the same manner that the compliant element
78
is assembled with the metal element
76
.
The preferred embodiment of the drill
30
is formed by the automatic spindle lock
33
, which includes the anvil
58
, and the automatic drag system
37
, which includes the anvil
58
.
In general, the above-identified embodiments are not to be construed as limiting the breadth of the present invention. Modifications, and other alternative constructions, will be apparent which are within the spirit and scope of the invention as defined in the appended claims.
Claims
- 1. A power driven rotary device, which comprises:a housing having at least one fixed wedging surface; a drive carrier mounted for rotation within the housing; a powered driver located within the housing for rotating the drive carrier; a drivable output member formed with an axis and located within the housing and mounted therein for rotation; the drivable output member including at least one movable wedging surface located in spatially facing relation to the fixed wedging surface; the drive carrier for rotating the drivable output member upon rotation of the drive carrier; at least one wedging element formed with an axis and located for free movement between the fixed wedging surface and the at least one movable wedging surface for movement with the drive carrier and the drivable output member when the drive carrier and the drivable output member are rotating at substantially the same speed, and for being wedged between the fixed wedging surface and the at least one movable wedging surface in a wedging mode when the drivable output member is rotating at a speed different from the speed of the drive carrier to lock the drivable output member with the housing; and means for maintaining the axis of the at least one wedging element in a prescribed orientation relative to the axis of the drivable output member.
- 2. The power driven rotary device as set forth in claim 1, wherein the drive carrier is formed with a portion which rotates in a circular path about an axis of the device, and which further comprises:the means for maintaining is formed with portions which are located in the circular path of, and engageable with, the drive carrier.
- 3. The power driven rotary device as set forth in claim 1, wherein the at least one wedging element is formed with a prescribed length and the means for maintaining is formed with a nest which is located in interfacing relation with portions of the at least one wedging element along the prescribed length.
- 4. The power driven rotary device as set forth in claim 1, wherein the at least one wedging element is formed about the axis thereof, and wherein the means for maintaining includes at least one blocking member which is positioned to preclude transaxial movement of the at least one wedging element in the direction of the at least one blocking member.
- 5. The power driven rotary device as set forth in claim 4, wherein the at least one blocking member covers an adjacent portion of the at least one wedging element while other spaced portions of the at least one wedging element remain uncovered for wedging engagement with the fixed wedging surface and the at least one movable wedging surface.
- 6. The power driven rotary device as set forth in claim 1, wherein the means for maintaining is movable independently of the fixed wedging surface and the at least one wedging surface.
- 7. The power driven rotary device as set forth in claim 1, wherein the drivable output member comprises:an output element located along an axis of the device for rotation; and a coupler mounted on the output element for engagement with the drive carrier to couple rotational drive from the powered driver to the drivable output member.
- 8. The power driven rotary device as set forth in claim 7, wherein the at least one wedging surface is formed on the coupler.
- 9. The power driven rotary device as set forth in claim 7, which further comprises:a drag surface on the coupler which is in engagement with an adjacent portion of the drive carrier to present a drag on the rotational movement of the output element when the speed of the output element is different from the speed of the drive carrier.
- 10. The power driven rotary device as set forth in claim 9, wherein the coupler comprises:a first section having an axis and composed of a first material; a second section having an axis and composed of a second material different from the first material; the first section joined with the second section with the axes thereof in alignment; and an exterior portion of the second section forming the drag surface and being in engagement with the adjacent portion of the drive carrier.
- 11. The power driven rotary device as set forth in claim 9, wherein the drag surface is formed by a band which is located about the coupler and is in engagement with the drive carrier.
- 12. The power driven rotary device as set forth in claim 1, which further comprises:a drag surface located on at least a portion of the drivable output member which is in engagement with an adjacent portion of the drive carrier to present a drag on the rotational movement of the drivable output member when the speed of the drivable output member is different from the speed of the drive carrier.
- 13. The power driven rotary device as set forth in claim 12, which further comprises:means responsive to the drivable output member being driven in an unloaded rotational mode for applying a braking force to the drivable output member; and means responsive to the drivable output member being driven in a loaded rotational mode for removing the braking force from the drivable output member.
- 14. The power driven rotary device as set forth in claim 13, wherein the means for applying a braking force comprises:a brake disk fixedly mounted within the housing; a brake collar mounted on the drivable output member and rotationally and axially movable therewith; and a biasing element which normally urges the drivable output member in an axial direction to place the brake collar in braking engagement with the brake disk.
- 15. The power driven rotary device as set forth in claims 14, wherein the means for removing the braking force comprises:a pair of spaced supports for supporting the drivable output member for rotational and axial movement relative to the pair of supports; and the biasing element being movable to allow axial movement of the drivable output member, to thereby move the brake collar out of engagement with the brake disk.
- 16. The power driven rotary device as set forth in claim 1, which further comprises:means responsive to the drivable output member being driven in an unloaded rotational mode for applying a braking force to the drivable output member; and means responsive to the drivable output member being driven in a loaded rotational mode for removing the braking force from the drivable output member.
- 17. The power driven rotary device as set forth in claim 16, wherein the means for applying a braking force comprises:a brake disk fixedly mounted within the housing; a brake collar mounted on the drivable output member and rotationally and axially movable therewith; and a biasing element which normally urges the drivable output member in an axial direction to place the brake collar in braking engagement with the brake disk.
- 18. The power driven rotary device as set forth in claim 17, wherein the means for removing the braking force comprises:a pair of spaced supports for supporting the drivable output member for rotational and axial movement relative to the pair of supports; and the biasing element being movable to allow axial movement of the drivable output member, to thereby move the brake collar out of engagement with the brake disk.
- 19. A power driven rotary device, which comprises:a housing having a plurality of fixed wedging surfaces at spaced locations about an axis of the device; a drive carrier mounted for rotation within the housing; a powered driver located within the housing for rotating the drive carrier; an output member having at least portions located within the housing and mounted therein for rotation; a coupler attached to the output member for rotation therewith and formed with a plurality of coupler wedging surfaces at spaced locations about the coupler; each of the plurality of fixed wedging surfaces being located spatially adjacent a respective one of the plurality of coupler wedging surfaces to form a plurality of pairs of opposed wedging surfaces; the drive carrier movable into engagement with the coupler for rotating the output member upon rotation of the drive carrier; a plurality of wedging rollers, each of which is located for free movement between a respective one of the plurality of pairs of opposed wedging surfaces; and a roller cage positioned about portions of each of the plurality of wedging rollers to preclude skewed movement of the wedging rollers in a transaxial direction.
- 20. The power driven rotary device as set forth in claim 19, wherein the roller cage comprises:a support member; a plurality of pairs of nests formed with the support member; and each of the plurality of nests formed to receive one of the plurality of wedging rollers.
- 21. The power driven rotary device as set forth in claim 20, wherein each of the plurality of nests comprises:a pair of legs which are spaced to receive a respective one of the plurality wedging rollers therebetween.
- 22. The power driven rotary device as set forth in claim 19, wherein the roller cage comprises:a circular band having a side surface; a plurality of pairs of spaced legs extending from the side surface of the circular band; and each of the pairs of spaced legs being spaced apart a distance sufficient for receipt of the respective wedging roller therebetween.
- 23. The power driven rotary device as set forth in claim 19, wherein the roller cage comprises:a circular band formed about an axis thereof and having an inner circular surface facing the axis; a plurality of ears formed with and extending radially inward from the inner circular surface of the circular band; each of the plurality of ears formed with spaced side edges on opposite sides thereof; a finger formed with and extending from each of the side edges of the plurality of ears to form a plurality of pairs of opposed fingers spaced for receipt of a respective one of the plurality of wedging rollers; and the plurality of pairs of opposed fingers extending in a common axial direction.
- 24. A power driven rotary device, which comprises:a housing; a drive carrier mounted for rotation within the housing; a powered driver located within the housing for rotating the drive carrier; a drivable output member having at least portions located within the housing and mounted therein for rotation; the drive carrier movable into engagement with, and for rotating, the drivable output member upon rotation of the drive carrier; and a drag surface located on at least a portion of the drivable output member which is in engagement with an adjacent portion of the drive carrier to present a drag on the rotational movement of the drivable output member when the speed of the drivable output member is different from the speed of the drive carrier.
- 25. The power driven rotary device as set forth in claim 24, wherein the drivable output member comprises:an output element located along an axis of the device for rotation; a coupler mounted on the output element for engagement with the drive carrier to couple rotational drive from the powered driver to the output element; and the drag surface is on the coupler and is in engagement with an adjacent portion of the drive carrier to present a drag on the rotational movement of the coupler and the output element when the speed of the output element is different from the speed of the drive carrier.
- 26. The power driven rotary device as set forth in claim 25, wherein the coupler comprises:a first section having an axis and composed of a first material; a second section having an axis and composed of a second material different from the first material; the first section joined with the second section with the axes thereof in alignment; and an exterior portion of the second section forming the drag surface and being in engagement with the adjacent portion of the drive carrier.
- 27. The power driven rotary device as set forth in claim 25, wherein the drag surface is formed by a band which is located about the coupler and is in engagement with the drive carrier.
- 28. A power driven rotary device, which comprises:a housing; a drive carrier mounted for rotation within the housing; a powered driver located within the housing for rotating the drive carrier; a drivable output member having at least portions located within the housing and mounted therein for rotation; the drive carrier movable into engagement with, and for rotating, the drivable output member upon rotation of the drive carrier; means responsive to the drivable output member being in an unloaded mode for applying a braking force to the drivable output member; and means responsive to the drivable output member being in a loaded mode for removing the braking force from the drivable output member.
- 29. The power driven rotary device as set forth in claim 28, wherein the means for applying a braking force comprises:a brake disk fixedly mounted within the housing; a brake collar mounted on the drivable output member and rotationally and axially movable therewith; and a biasing element which normally urges the drivable output member in an axial direction to place the brake collar in braking engagement with the brake disk.
- 30. The power driven rotary device as set forth in claim 29, which further comprises:a pair of opposed slots formed internally of the housing; a pair of ears formed on opposite edge portions of the brake disk and extending in a common direction; and the ears of the brake disk being fixedly located in the pair of slots formed in the housing.
- 31. The power driven rotary device as set forth in claim 29, which further comprises:a braking pad formed on a surface of the brake collar which interfaces, and is engageable, with the brake disk.
- 32. The power driven rotary device as set forth in claim 29, which further comprises:a limiting collar formed on the drivable output member and movable therewith at least in an axial direction; the biasing element is a compression spring having a first end and a second end; the first end of the compression spring being positioned at a fixed location within the housing spaced from the limiting collar; and the second end of the compression spring being positioned in engagement with the limiting collar.
- 33. The power driven rotary device as set forth in claim 32,the compression spring being in a comparatively expanded state when the drivable output member is in a no load condition whereby the spring is urging the drivable output member in a first direction; and the compression spring being in a compressed state when the drivable output member is moved, under a load condition, axially in a second direction opposite the first direction whereby the limiting collar is moved toward the fixed location of the first end of the compression spring.
- 34. The power driven rotary device as set forth in claim 33, which further comprises:a stop positioned in the path of the limiting collar to limit the distance the drivable output member can be urged in the first direction.
- 35. The power driven rotary device as set forth in claim 28, wherein the means for removing the braking force comprises:a pair of spaced supports for supporting the drivable output member for rotational and axial movement relative to the pair of supports; and the biasing element being movable to allow axial movement of the drivable output member, to thereby move the brake collar out of engagement with the brake disk.
- 36. A power driven rotary device, which comprises:a housing; a non-rotatable surface located fixedly in the housing and facing a rotary-device axis of the rotary device; at least a portion of the non-rotatable surface forming a fixed wedging surface; a drive carrier mounted for rotation about the rotary-device axis and within the housing; a drivable output member having at least portions located within the housing and mounted therein for rotation along the rotary-device axis; the drivable output member formed with an output-member surface which is spatially facing the non-rotatable surface; the output-member surface formed with a movable wedging surface locatable in spatially facing relation to the fixed wedging surface; the drive carrier movable into engagement with, and for rotating, the drivable output member upon rotation of the drive carrier; a wedging element extending along a wedging-element axis and located for independent movement between, and formed with respective spaced surfaces which directly interface with, the non-rotatable surface and the output-member surface; the wedging element locatable in a non-wedging mode between the non-rotating surface and the output-member surface for movement with the drive carrier and the drivable output member when the drive carrier and the drivable output member are rotating at substantially the same speed; the wedging element locatable between the fixed wedging surface and the movable wedging surface in a wedging mode when the drivable output member is rotating at a speed different from the speed of the drive carrier to lock the output member with the housing; and a nest formed with structure for receipt of the wedging element therein in a prescribed orientation to maintain the wedging-element axis substantially parallel with the rotary-device axis during the non-wedging and wedging modes.
- 37. The power driven rotary device as set forth in claim 36, which further comprises:the structure of the nest being formed to receive the wedging element to maintain the respective spaced surfaces of the wedging element in direct interface with the non-rotatable surface and the output-member surface during the non-wedging and wedging modes.
- 38. The power driven rotary device as set forth in claim 37, wherein the structure of the nest comprises:a ring having a ring axis and an inner side wall facing the ring axis; an ear formed on the inner side wall toward the ring axis; a pair of spaced fingers extending in parallel in a common direction from, and perpendicular to, the ear and spaced apart for receipt of the wedging element therebetween, where the spaced fingers engage portions of the surface of the wedging element exclusive of the respective spaced surfaces thereof.
- 39. The power driven rotary device as set forth in claim 36, wherein the structure of the nest comprises:a ring having a ring axis and an inner side wall facing the ring axis; a ear formed on the inner side wall and extending toward the ring axis; a pair of spaced interfacing fingers extending in parallel from, and perpendicular to, the ear and spaced apart for receipt of the wedging element therebetween.
- 40. The power driven rotary device as set forth in claim 36, wherein the structure of the nest is in engagement with the wedging element to maintain, during the wedging mode, all surface portions of the wedging element (1) which are immediately adjacent the fixed wedging surface in full engagement therewith, and (2) which are immediately adjacent the movable wedging surface in full engagement therewith.
US Referenced Citations (7)