Reciprocating Action Drive with Uni-directional Output

Abstract

A reciprocating action drive for converting reciprocating linear motion to uni-directional rotational motion is disclosed. The reciprocating action drive has a lever arm connected to a drive shaft via a first overrunning clutch such that when the lever arm is rotated in a first direction of rotation by a reciprocating linear motion, the drive shaft is rotates in the same direction. A further overrunning clutch connects the drive shaft such that the drive shaft may rotate in the first direction with respect to the frame, but not in the second, opposite direction. Such an arrangement prevents the drive shaft being driven in the second opposite, direction with respect to the frame. This prevents the lever arms being driven to interfere with any connection they may have to a source of linear reciprocating motion, thereby avoiding damage to such a connection.

Claims

1: A reciprocating action drive, comprising: a first lever arm connected to a drive shaft via a first overrunning clutch such that when said first lever arm is rotated in a first direction of rotation, said drive shaft also rotates in said first direction of rotational motion about a common axis of rotation; and a further overrunning clutch connecting said drive shaft to a frame such that said drive shaft may rotate in a first direction of rotation with respect to said frame, but not in a second, opposite direction of rotation about said common axis of rotation.

2: The reciprocating action drive of claim 1, further comprising: a second lever arm connected to said drive shaft via a second overrunning clutch such that when said second lever arm is rotated in said first direction of rotation, said drive shaft is also rotated in said first direction of rotational motion about said common axis of rotation.

3: The reciprocating action drive of claim 2, further comprising: A direction reversing mechanism functionally attaching said first lever arm to said second lever arm such when said first lever arm is moved in said first direction of rotation, said second lever arm is moved in said second, opposite direction of rotation.

4: The reciprocating action drive of claim 3, wherein, said direction reversing mechanism comprises: a first beveled gear connected to said first lever arm; a second beveled gear connected to said second lever arm; and one or more third bevel gears functionally connecting said first beveled gear to said second beveled gear.

5: The reciprocating action drive of claim 3, wherein, said direction reversing mechanism comprises: a flexible cable connecting said first lever arm to said second lever arm, and, wherein, said flexible cable passes over a restraining channel attached to, or a part of, said frame such that when said first lever arm is moved in said first direction of rotation, said second lever arm is moved in said second, opposite direction of rotation.

6: The reciprocating action drive of claim 5, wherein, said flexible cable is a stainless steel lanyard.

7: The reciprocating action drive of claim 5, wherein, said restraining channel further comprises one or more roller bearings.

8: The reciprocating action drive of claim 1, wherein one or more of said overrunning clutches is a magnetically sprung overrunning clutch comprising one or more pivoting sprags located between said drive shaft and either said frame or one of said lever arms, and said pivoting sprags each comprise at least one sprag permanent magnet.

9: The reciprocating action drive of claim 8, wherein said sprag permanent magnet is a rare-earth, permanent magnet.

10: The reciprocating action drive of claim 8, further comprising one or more anchor magnets corresponding to said pivoting sprags, and, wherein, said anchor magnets are fixed to either said drive shaft or to one of said lever arms.

11: The reciprocating action drive of claim 10 wherein one or more of said anchor magnets is an electro-magnet.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0026] FIG. 1 shows a schematic, isometric view of a single lever, reciprocating action drive with uni-directional output of one embodiment of the present invention.

[0027] FIG. 2 shows a schematic, isometric view of a double lever, reciprocating action drive with uni-directional output of one embodiment of the present invention.

[0028] FIG. 3A shows a schematic, side view of a double lever, reciprocating action drive with uni-directional output of one embodiment of the present invention.

[0029] FIG. 3B shows a schematic, plan view of a double lever, reciprocating action drive with uni-directional output of one embodiment of the present invention.

[0030] FIG. 4 shows a schematic, plan view of a reciprocating action drive with a beveled gear reversing mechanism of one embodiment of the present invention.

[0031] FIG. 5 shows a schematic side view of a bicycle fitted with a reciprocating action drive having a flexible cable reversing mechanism of one embodiment of the present invention.

[0032] FIG. 6 shows a schematic close up view of a reciprocating action drive having a flexible cable reversing mechanism of one embodiment of the present invention.

[0033] FIG. 7 shows a schematic X-sectional view of a magnetically sprung overrunning clutch of one embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

[0034] The preferred embodiments of the present invention will now be described in more detail with reference to the drawings in which identical elements in the various figures are, as far as possible, identified with the same reference numerals. These embodiments are provided by way of explanation of the present invention, which is not, however, intended to be limited thereto. Those of ordinary skill in the art may appreciate upon reading the present specification and viewing the present drawings that various modifications and variations may be made thereto without departing from the spirit of the invention.

[0035] FIG. 1 shows a schematic, isometric view of a single lever, reciprocating action drive, with uni-directional output, of one embodiment of the present invention.

[0036] The single lever, reciprocating action drive, with uni-directional output 101, shown in FIG. 1 includes a first lever arm 110 attached to a drive shaft 115 via a first overrunning clutch 120. This arrangement may allow the first lever arm 110, when driven in a first direction of rotation 125, by a source of linear, reciprocating motion 126, to cause the drive shaft 115 to rotate in a first direction of rotation 125. When the first lever arm 110 is, however, moved in a second, opposite direction of rotation 150, the first overrunning clutch 120 may allow the first lever arm 110 to free-wheel with respect to the drive shaft 115. This arrangement may, therefore, enable the linear reciprocating motion provided by a source of linear, reciprocating motion 126, to be converted into uni-directional rotary motion.

[0037] A further overrunning clutch 140 may connect the drive shaft 115 to a frame 145 such that the drive shaft may rotate in the first direction of rotation 125 with respect to the frame 145, but not in a second, opposite direction of rotation 150. This may, for instance, provide protection against damage that may be caused to any linkage between the source of linear, reciprocating motion 126, and the reciprocating action drive. if the first lever arm 110 is driven by the drive shaft 115 in the second, opposite direction of rotation 150 to a point at which any such linkage may be compromised.

[0038] In the arrangement shown in FIG. 1, the motion of the first lever arm 110 in the second, opposite direction of rotation 150, i.e., when the lever arm is free-wheeling with respect to the drive shaft, may be driven by the source of linear, reciprocating motion 126, or it may also, or instead, be provided by a spring element that may be suitably situated between the frame 145 and the first lever arm 110.

[0039] FIG. 2 shows a schematic, isometric view of a double lever, reciprocating action drive with uni-directional output 102 of one embodiment of the present invention.

[0040] As shown in FIG. 2, the double lever, reciprocating action drive with uni-directional output 102 includes both a first lever arm 110 and a second lever arm 130. These may be connected to the drive shaft 115 by, respectively, a first overrunning clutch 120 and a second overrunning clutch 135. Each of these overrunning clutches may allow their respective lever arms, when driven inn a first direction of rotation 125 by a source of linear, reciprocating motion, to impart movement to the drive shaft 115 in the first direction of rotation 125. However, the overrunning clutches may overrun, or free-wheel, when the levers are moved to rotate in a second, opposite direction of rotation 150. In this way, a reciprocating, linear, or near linear, motion may be converted to uni-directional rotary motion about an axis of rotation 170.

[0041] In some embodiments of a double lever, reciprocating action drive with uni-directional output, it may be desirable that the lever arms are retained within a certain range of motion. This limit on the lever arms range of motion may, for instance, be occasioned by mechanical linkages to a source of linear, reciprocating motion. Or it may be due to limit stops placed to constrain the lever arm range of motion. In order to prevent the drive shaft 115 being accidently, or deliberately, driven in the wrong direction, i.e., the second, opposite direction of rotation 150, a third overrunning clutch 140 may be used. The third overrunning clutch 140 may link the drive shaft 115 to a frame 145 such that the drive shaft 115 may rotate in the first direction of rotation 125 but not in the second, opposite direction of rotation 150. This may prevent the drive shaft 115 being used to drive the lever arms out of their desired range of motion.

[0042] As shown in FIG. 2, the lever arms may be functionally linked by a direction reversing mechanism 155. This may be useful when the source of linear, reciprocating motion only provides a driving force in one direction. The direction reversing mechanism 155 may then allow part of the force being used to drive the first lever arm 110 in a first direction of rotation 125 to simultaneously drive the second lever arm 130 in a second, opposite direction of rotation 150, and so place it in position to be powered on the next power stroke of the source of linear, reciprocating motion. The uni-direction powered source of linear, reciprocating motion may, for instance, be propulsion mechanisms such as, but not limited to, a cyclist's legs, or the pistons of an internal combustion engine.

[0043] In FIG. 2, an exemplary direction reversing mechanism 155 is shown that is a flexible cable 160 running over a restraining channel 165 that may be attached to the frame 145. One of ordinary skill in the art will, however, appreciate there are many other forms the direction reversing mechanism 155 may take such as, but not limited to, a beveled gear reversing mechanism.

[0044] FIG. 3A shows a schematic, side view of a double lever, reciprocating action drive with uni-directional output 102 of one embodiment of the present invention.

[0045] The double lever, reciprocating action drive with uni-directional output 102 shown in FIG. 3A includes a first lever arm 110 and a second lever arm 130. The first lever arm 110 may be attached to the drive shaft 115 via a first overrunning clutch (not visible in FIG. 3A), while the second lever arm 130 may be attached to the drive shaft 115 via a second overrunning clutch 135. Both overrunning clutches may be connected such that when the lever arms are moved to rotate in a first direction of rotation 125, the drive shaft 115 may also be moved to rotate in the first direction of rotation 125. However, when the levers are moved in the second, opposite direction of rotation 150, the overrunning clutches allow them to free-wheel with respect to the drive shaft 115.

[0046] The drive shaft 115 may also be attached to a frame 145 via a third overrunning clutch 140. The third overrunning clutch 140 may be arranged so that the drive shaft 115 may free-wheel when rotated in the first direction of rotation 125 with respect to the frame 145, but to lockup if the drive shaft 115 is attempted to be rotated in the second, opposite direction of rotation 150 with respect to the frame 145. In this manner, the lever arms may be protected from being accidently, or deliberately, driven in the second, opposite direction of rotation 150 with respect to the frame 145.

[0047] FIG. 3B shows a schematic, plan view of a double lever, reciprocating action drive with uni-directional output of one embodiment of the present invention.

[0048] The double lever, reciprocating action drive with uni-directional output 102 shown in the plan view of FIG. 3B includes a first lever arm 110 connected via a first overrunning clutch 120 to a drive shaft 115, and a second lever arm 130 connected via a second overrunning clutch 135 to the drive shaft 115. The drive shaft 115 may also be connected to a frame 145 via one or more third overrunning clutches 140. All the overrunning clutches and the drive shaft 115 rotate about an axis of rotation 170.

[0049] FIG. 4 shows a schematic, plan view of a reciprocating action drive with a beveled gear reversing mechanism 103 of one embodiment of the present invention.

[0050] The reciprocating action drive with a beveled gear reversing mechanism 103 may include a first lever arm 110 that may be connected to a drive shaft 115 via a first overrunning clutch 120. An outer shell of the first overrunning clutch 120 may also be directly connected to a first beveled gear 175. There may also be a second lever arm 130 connected to the drive shaft 115 via a second overrunning clutch 135. The outer shell of the second overrunning clutch 135 may be directly connected to a second beveled gear 180.

[0051] The first beveled gear 175 and the second beveled gear 180 may be functionally connected via one or more third bevel gears 185. The first and second bevel gears may rotate around the same axis of rotation 170 as the drive shaft 115. The third bevel gears 185 may rotate about a second axis of rotation 190, that may be orthogonal to the drive shaft axis of rotation. The combination of beveled gears may thus provide a direction reversing mechanism in which moving the first lever arm 110 in one rotational direction causes the second lever arm 130 to rotate in a second, opposite direction of rotation, and vice versa.

[0052] The drive shaft 115 may also be connected to a frame 145 via one or more third overrunning clutch 140. The third overrunning clutch 140 may be arranged such that the drive shaft 115 may free-wheel with respect to the frame 145 in the rotational direction in which the lever arms may provide power to the drive shaft.

[0053] FIG. 5 shows a schematic side view of a bicycle 195 fitted with a reciprocating action drive having a flexible cable reversing mechanism 106 of one embodiment of the present invention.

[0054] The bicycle 195 may include a frame 145 and two wheels, free to rotate in either direction with respect to the bicycle frame. The bicycle 195 may be propelled via a drive shaft 115 that may be directly connected to a chain ring 215 that may in turn drive the bicycle rear tire 205 via a drive chain 210. The drive chain 210 may engage a sprocket wheel 211 on a rear hub that may be directly connected to a rear wheel supporting a bicycle rear tire 205.

[0055] The drive shaft 115 may be driven by a first lever arm 110 and a second lever arm 130 that may be connected to the drive shaft 115 by, respectively, a first overrunning clutch 120 (not shown in FIG. 5) and a second overrunning clutch 135. The drive shaft 115 may also be connected to the bicycle frame 145 via a third overrunning clutch 140.

[0056] The first and second lever arms may be connected by a flexible cable 160 that may pass over a restraining channel 165 that may be connected to the frame 145, thereby forming a direction reversing mechanism.

[0057] The flexible cable 160 may be any suitable cable such as, but not limited to, a stainless steel lanyard, or a suitably sized cable, rope or tape, that may be made of a material or fibers, such as, but not limited to, stainless steel, steel, aluminum, Nylon, Kevlar, polyester, polypropylene, poly-aramid, cotton, leather, wool, or silk, or some combination thereof.

[0058] FIG. 6 shows a schematic close up view of a reciprocating action drive having a flexible cable reversing mechanism 107 of one embodiment of the present invention.

[0059] Shown in FIG. 6 are a first lever arm 110 and a second lever arm 130 linked by a flexible cable 160 that runs over a restraining channel 165 attached to the frame 145, that may, for instance, be a bicycle frame. This arrangement may form a direction reversing mechanism that, when the first lever arm 110 is driven in one direction, the second lever arm 130 may be driven in an opposite direction, and vice versa.

[0060] The first lever arm 110 is shown connected to the drive shaft 115 via a second overrunning clutch 135. The drive shaft 115 may also be connected directly to a chain ring 215, and via a third overrunning clutch 140 to the frame 145. The chain ring 215 may be connected to a drive chain 210 that may be used to power a bicycle via a rear wheel.

[0061] The flexible cable 160 may be made of any suitable material or fibers, such as, but not limited to, stainless steel, steel, aluminum, Nylon, Kevlar, polyester, polypropylene, poly-aramid, cotton, leather, wool, or silk, or some combination thereof.

[0062] The restraining channel 165 may simply rely on having a low friction surface such as, but not limited to, a nylon, Teflon, steel, aluminum or stainless steel, or some combination thereof, or it may include bearing such as, but not limited to, roller bearings made of a suitable material such as, but not limited to, nylon, aluminum, steel or stainless steel, or some combination thereof.

[0063] The restraining channel 165 may be a part of the frame 145 or it may be rigidly attached to the frame 145 by some suitable mechanism such as, but not limited to, welding, gluing or bolting, or some combination thereof.

[0064] FIG. 7 shows a schematic X-sectional view of a magnetically sprung overrunning clutch of one embodiment of the present invention.

[0065] The magnetically sprung overrunning clutch 220 may include one or more pivoting sprags 225 each of which may include one or more sprag permanent magnet 230. The pivoting sprags 225 may be situated between an inner surface 245 of a magnetically sprung overrunning clutch outer shell and a anchor magnet holding element 240. The magnetically sprung overrunning clutch outer shell may be directly connected to, or be a part of a first lever arm 110. The anchor magnet holding element 240 may be directly connected to, or be a part of the drive shaft 115. In that way, the pivoting sprags 225 may be functionally situated between the first lever arm 110 and the drive shaft 115.

[0066] The sprag permanent magnet 230 may be attracted to a ferromagnetic material attached to the drive shaft or to the anchor magnet holding element 240. The ferromagnetic material may, for instance, be an anchor magnet 235. The sprag permanent magnet 230 and the anchor magnets 235 may either, or both, be permanent magnets such as, but not limited to, neodymium rare-earth magnets.

[0067] In an alternate embodiment, one or more of the anchor magnets 235 may be electro-magnets.

[0068] Although this invention has been described with a certain degree of particularity, it is to be understood that the present disclosure has been made only by way of illustration and that numerous changes in the details of construction and arrangement of parts may be resorted to without departing from the spirit and the scope of the invention.