ROWING MACHINE INCLUDING A GEAR SHIFT MECHANISM

Abstract

Rowing machines are described that permit a rower to adjust the rowing resistance using a gear shift mechanism. The rowing machine includes a handle connected to a chain, which passes, sequentially, over a derailleur and then to the gears of the gear cassette. The gear cassette is coupled to a resistance unit, which may be similar to resistance units used in off wheel bicycle trainers. This configuration of derailleur and gear cassette permit the rower to smoothly select a gear.

Claims

1. A rowing machine comprising: a resistance unit including a gear cassette comprising a plurality of gears coupled to a mechanism to resist the rotation of the gear cassette; a frame adapted for placing on the ground and attached to the resistance unit; a seat movable along the frame; a handle; a chain having a first end attached to the handle and a second end attached to the frame; a derailleur attached to the frame; and a gear shifter operably connected to the derailleur, where the chain extends, sequentially, from the handle, through the derailleur, and engages a gear of the plurality of gears, such that the engaged gear is selectable using the gear shifter.

2. The rowing machine of claim 1, where the resistance unit is an off-wheel bicycle trainer resistance unit.

3. The rowing machine of claim 1, where the mechanism to resist the rotation of the gears includes a one-way clutch connecting the mechanism to the gear cassette.

4. The rowing machine of claim 1, where the mechanism to resist the rotation of the gears includes a flywheel.

5. The rowing machine of claim 1, where the mechanism to resist the rotation of the gears includes an electromagnet.

6. The rowing machine of claim 1, where the rowing machine includes a return mechanism disposed between the second end of the chain and the frame.

7. The rowing machine of claim 6, where the return mechanism includes an elastic cord.

8. A rowing machine attachment connectable to a resistance unit, where the resistance unit includes an axle and a gear cassette comprising a plurality of gears coupled to a mechanism to resist the rotation of the gear cassette, said rowing training attachment comprising: a frame adapted for placing on the ground and including a fork end adapted to accept the axle of the resistance unit; a seat movable along the frame; a handle; a chain having a first end attached to the handle and a second end attached to the frame; a derailleur attached to the frame; and a gear shifter operably connected to the derailleur, where, when the fork end of the frame is attached to the axle of the resistance unit and where the chain extends, sequentially, from the handle, through the derailleur, and engages a gear of the plurality of gears, such that the engaged gear is selectable using the gear shifter.

9. The rowing machine attachment of claim 8, where the resistance unit is an off-wheel bicycle trainer resistance unit.

10. The rowing machine attachment of claim 8, where the mechanism to resist the rotation of the gears includes a one-way clutch connecting the mechanism to the gear cassette.

11. The rowing machine attachment of claim 8, where the mechanism to resist the rotation of the gears includes a flywheel.

12. The rowing machine attachment of claim 8, where the mechanism to resist the rotation of the gears includes an electromagnet.

13. The rowing machine attachment of claim 8, where the rowing machine includes a return mechanism disposed between the second end of the chain and the frame.

14. The rowing machine attachment of claim 13, where the return mechanism includes an elastic cord.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

[0009] FIGS. 1 and 2 are side and top views, respectively, of a first embodiment rowing machine with the rower at the end of a stroke;

[0010] FIG. 3 is a view of a handle and chain;

[0011] FIG. 4 is a side view illustrating one embodiment of the connection of the chain and resistance unit;

[0012] FIG. 5 is an exploded view 5-5 of showing one embodiment of a chain return mechanism; and

[0013] FIG. 6 is a side view of the first embodiment rowing attachment attached to the bicycle trainer resistance unit, with the rower at the beginning of a stroke.

[0014] Reference symbols are used in the Figures to indicate certain components, aspects or features shown therein, with reference symbols common to more than one Figure indicating like components, aspects or features shown therein.

DETAILED DESCRIPTION OF THE INVENTION

[0015] FIGS. 1 and 2 are side and top views, respectively, of a first embodiment rowing machine 200, with a rower R in at the end of a stroke, FIG. 3 is a top view of a handle 237 and chain 233; FIG. 4 is a side view illustrating the chain and a resistance unit 250; and FIG. 5 is an exploded view 5-5 of showing one embodiment of a chain return mechanism 232.

[0016] As shown in FIGS. 1 and 2, rowing machine 200 includes a frame 210, a resistance unit 250, and power transmission components 230 connecting the frame and resistance unit. Frame 210 includes a first portion 211, a second portion 219 and a third portion 221. First portion 211 is generally horizontal. Second portion 219 is attached to first portion 211 and includes a first end 223 that extends to the ground and a second end 225 attached to an axle 253 of resistance unit 250 and includes legs 213 for supporting the rowing attachment on the ground and a foot support 215 including foot straps 216. Third portion 221 is attached to and extends above second portion 219.

[0017] Resistance unit 250 includes a freewheel or freehub assembly including a cassette of gears 251 connected to axle 253 through a one-way clutch that engages with a resistance mechanism (both of which are not shown) within the resistance unit. Resistance unit 250 may, for example and without limitation, be generally similar to prior art resistance units of a wheel off bicycle trainer, such as the Tacx NEO (Garmin Ltd, Schaffhausen, Switzerland). Such resistance units provide a force to resist the rotation of the cassette of gears 251 in one direction and provides little force to resist the rotation of the cassette of gears in the opposite direction. Resistance unit 250 may include one or more of a flywheel, an air or water resistance mechanism, or a magnetic resistance mechanism that is electronically controllable. Resistance unit 250 also includes sensors to measure the power and cadence of the cassette of gears 251, and electronics to accept the sensor measurements, control the resistance to the cassette of gears, and provide information for display on a screen 255.

[0018] Power transmission components 230 include chain 233 coupled to the handle 237 with an attachment ring 301, a first chain guide 241 attached to third frame portion 221, a derailleur 243 attached to second end 225 in a position that is above cassette of gears 251 (as shown in FIG. 4), a second chain guide 245 attached to second portion 219, and a chain return mechanism 232. Power transmission components 230 also include a gear shifter 247 attached to the handle 237 and a cable 249 connecting the gear shifter and derailleur 243, and a seat 217 including rollers to allow the seat to move along first frame portion 210. In certain embodiments, first portion 211 is angled relative to the horizontal to aid the return of rower and at the end of the stoke SRV

[0019] In an alternative embodiment, derailleur 243 may be an electronic system, such as a Shimano Di2 electric drivetrain (Shimano Inc, Sakai, Japan) or Campagnolo EPS (Campagnolo Vicenza, Italy), or a wireless system, such as SRAM eTap (SRAM, Chicago, Ill.).

[0020] Chain return mechanism 232, shown in FIGS. 3 and 5, is generally contained within second portion 219 and includes an elastic cord 235 coupled to an end of chain 233, rollers 501, 503, 505, and 507 supported on second frame portion 219 by bolts 511 and nuts 513. An end 239 of elastic cord 235 is attached to first end 223. The handle 237 also includes a mount 303 for a mobile device (not shown). The combination of chain 233 and elastic cord 235, referred to herein as a compound cable 231, extends from the handle 237 to first end 223, with chain 233 being guided over first chain guide 241, through derailleur 243, over gears 251, and guided over second chain guide 245. Elastic cord 235 extend from chain 233 around rollers 501, 503, 505, and 507 and is attached to frame 210 at first end 223.

[0021] In an alternative embodiment, chain return mechanism 232 includes an elastic cord that pulls on an end of chain 233 as provided, for example and without limitation, by the Concept2 skewer assembly (Morrisville, Vt.) (see, for example, https://shop.concept2.com/model-b/249-skewer-assembly. html?search_query=skewer+assembly&results=6). In another alternative embodiment, chain return mechanism is a spring loaded cylinder that takes up the slack in chain 233, or a gravity return mechanism (see, for example, US Patent Application Publication No. US20140243163A1, the content of which are incorporated by reference).

[0022] Resistance unit 250 thus provides a force that counters forces provided by a rower. The force provided by resistance unit 250 is transferred from axle 253, to one of gears of gear cassette 251, to chain 233 of compound cable 231, to the handle 237. In addition to resistance due to a flywheel or an electromagnetic or other mechanism for controlling the resistance, the gear shifter 247 and derailleurs 243 allow for rower to control the resistance. Slack in chain 233 is taken up by chain return mechanism 232.

[0023] One use of rowing attachment 200 is illustrated with reference to FIG. 1 and with FIG. 6, which is a side view of the first embodiment rowing machine attached to the bicycle trainer resistance unit, with the rower at the beginning of a stroke.

[0024] At the beginning of a stroke, as shown in FIG. 6, the arms of rower R are fully extended, seat 217 is in a forward position, and elastic cord 235 retracts compound cable 231 towards first end 223. Rower R then pulls on the handle 237 towards their body while pushing their feet against foot support 215 and extending their legs. Both seat 217 and the handle 237 then move backwards, with chain 233 being pulled through the resistance unit 250 and with elastic cord 235 elongating. During a stroke resistance unit 250 provides a resistance simulating the force during rowing.

[0025] During a stoke, as the handle 237 is pulled backwards and away from resistance unit 250, a tension is provided to chain 233 by resistance unit 250 and while elastic cord 235 takes up any slack in compound cable 231. The tension in chain 233 is provided by the force required to rotate gears 251, which may be regulated by the rower using gear shifter 247 to activate derailleur 243 and thus select a gear of gears 251. Alternatively, or in combination with gear shifter 247, the force required to rotate gears 251 may be adjusted using software in resistance unit 250. Thus, for example, certain embodiments of resistance unit 250 include sensors to monitor the rotation speed of gears 251 and electronics to determine power expended during rowing. In certain other embodiments, resistance unit 250 is in communication with a computer or electronic device, such as a smartphone, which can receive information from resistance unit 250 and which may also provide instructions to the resistance unit to modify the resistance provided by the resistance unit. The end of stroke is illustrated in FIG. 1.

[0026] After the end of the stroke, rower R moves forward to the position shown in FIG. 6. The one-way clutch permits the chain to move without resistance through resistance unit 250 and return mechanism 232 takes up slack in compound chain 231.

[0027] The inventor found that a rowing machine having a derailleur below the gears, as is generally provided on bicycles or bicycle trainers provides engagement of the one way-clutch at the beginning of a stroke that is not smooth. Thus, for example, shifting under load, as on an upstroke, can be painful for the rower. In contrast, placing the derailleur above the gears, as in FIG. 4 forces the gear shift to happen on a down stroke, when system is not under load and helps to dampen one way-clutch engagement at the beginning of a stroke, resulting in a smoother and more natural motion.

[0028] Reference throughout this specification to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrases “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures or characteristics may be combined in any suitable manner, as would be apparent to one of ordinary skill in the art from this disclosure, in one or more embodiments.

[0029] Similarly, it should be appreciated that in the above description of exemplary embodiments of the invention, various features of the invention are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure and aiding in the understanding of one or more of the various inventive aspects. This method of disclosure, however, is not to be interpreted as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive aspects lie in less than all features of a single foregoing disclosed embodiment. Thus, the claims following the Detailed Description are hereby expressly incorporated into this Detailed Description, with each claim standing on its own as a separate embodiment of this invention.

[0030] Thus, while there has been described what is believed to be the preferred embodiments of the invention, those skilled in the art will recognize that other and further modifications may be made thereto without departing from the spirit of the invention, and it is intended to claim all such changes and modifications as fall within the scope of the invention. Steps may be added or deleted to methods described within the scope of the present invention.