DE29717977U1 - Infinitely adjustable hydrostatic compact transmission for bicycles - Google Patents

Description

Herold Marc-Rene Geiser &iacgr;^&idigr; |*· * ,·.·,.^hydro§tetfches compact transmission for bicycles

PATENT DESCRIPTION

Continuously adjustable hydrostatic compact transmission for bicycles

Hydrostatic drives for bicycles are well known (PaLNr. DE 43 35 494 Al and Pat. No. DE 39 28 231 Al). They all pursue the purpose of using the advantages of a continuously variable gear change option as well as the large gear ratio range.

The disadvantages of these systems are that on the one hand the bicycle frame has to be adapted, on the other hand the removal of the drive wheel requires the cables to be separated, which in turn represents an increased technical effort. The system's motor is also not designed to be adjustable, which is why the adjustability of the gear is only controlled via the pump, with the disadvantage of lower pump performance with the same motor absorption capacity. In addition, it is not a compact gearbox and therefore cannot be easily replaced.

In PaLNr. DE 39 28 231 Al, the parts of the transmission are designed as integrated parts of the wheel hub, i.e. they are firmly connected to the wheel and cannot be easily replaced or mounted on a different wheel. In addition, the use of the swash plate technology requires a large number of parts, which makes production more expensive and adds weight, which has a negative effect on the bike's handling and image with customers.

The invention specified in claim 1 is based on the problem of building a compact, lightweight, hydrostatically continuously variable transmission that can be mounted directly on the drive wheel. The transmission should cover as wide a speed range as possible. The adaptation to the driving conditions should be carried out independently or manually controlled. In addition, the efficiency should be as high as possible so that the transmission can be used for bicycles

Herold Marc-Rene Geiser *··* ··* ··· ·· Hydrostatic compact transmission for bicycles

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It should be possible to use the gearbox without modifying the existing vehicle components. It should be easy to dismantle so that the impeller can be replaced quickly and inexpensively in the event of defects.

This problem is solved by the features listed in claim 1:

- concentric arrangement of pump and motor

- a stator with a non-concentric bore and mounted between the pump and the motor

- Channels in the stator

- movable stator

The proposed transmission is impressive due to its compactness and the short paths of the operating fluid. It requires fewer parts than the solutions mentioned, is easy to integrate and the efficiency is higher due to the rotating housing walls. It can be installed directly on/in a wheel or similar to save space. The large speed range far exceeds that of the known derailleur or hub gears. It also offers a significant weight advantage. It can be attached directly to known bicycle components and does not require any modification of the frame. Thanks to the stepless control, the rider can always work at the optimal cadence for him, which brings a considerable increase in comfort and performance.

Description of how it works

Fig. 1 shows a section through the vane cell gearbox. You can see (1) the outer rotor,

(2) the inner rotor, (3) the non-concentric stator ring, (4) one of the two channels in the stator, (5) the hills. The inner rotor (2) is driven - e.g. via a toothed belt. As a result, the operating fluid flows from the pressure side (7) through the channel (4) in the stator ring (3) into the suction side (8), which sets the outer rotor (1) in motion and passes its rotational movement on to the output. As a result of the counterpressure, a pressure builds up in the inner part of the gear, which causes the stator ring (3) - which is connected by means of a

Herold Marc-Rene Geiser *··" ··* ··· ·· Hydrostatic compact transmission for bicycles

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Spring is held concentrically and cannot rotate - shifts to the left, whereby the suction chamber (8) in the outer part increases. At the same time, the pressure chamber (7) in the inner part decreases. In this way, the ratio between the pump's delivery rate in the inner part and the motor's absorption capacity in the outer part is regulated depending on the force ratio between the drive and output.

The following applies:

pump engine high torque small pressure chamber large suction chamber high speed large printing space small suction chamber

The construction of the inner vane motor can be carried out in a known manner, the vanes (5) can be pressed against the stator ring by spring force or pressure.

In the outer rotor, however, there is a groove (9) into which a spring or rubber band (10) is inserted, which presses the vanes (5) inwards towards the stator ring (3).

When the pump is not in use, this arrangement automatically sets the pump to freewheel by centering the stator ring.

It is also possible to arrange the drive and output in reverse. The stator ring only needs to be reversed, i.e. centered with its inner diameter. The stator ring is connected to a spring on the side via a plate. The preload of the spring can be adjusted, even during operation if necessary. It is also possible to do without the spring and control the position of the stator manually. The volume ratio between the pump and the motor is normally 1:1. However, since extreme stator positions are not as efficient, the ratio between the pump and the motor can also be changed. The basic gear ratio on a bicycle is 1:4, for example.

Thanks to its design, the gearbox can be directly plugged or screwed onto standard bicycle wheels. It is also possible to install it directly into the bicycle hub.

Herold Marc-Rene Geiser ·· ·· ..·»* Hydrostatic compact transmission for bicycles

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or to make a special hub for it, to which the gearbox is connected using a plug-in coupling. Of course, the gearbox can also be mounted at other points on the bike, e.g. at the bottom bracket.

It is also possible to replace the vane cells with radial pistons, whose strokes are also controlled by a non-concentric ring.

Claims (8)

Herold Marc-Rene Geiser *··* ··* ···*·· Hydrostatic compact transmission for bicycles 1. Continuously adjustable hydrostatic compact transmission for bicycles, characterized in that - a vane motor and a vane pump are arranged so that a outer rotor orbits concentrically around an inner rotor, i.e. lies on the same level as it, and encloses it, - the stator is mounted between the two gear units and consists of a non-concentric ring. - the stator has channels that are suitable for conveying the operating fluid from the pressure side by half a turn in order to reach the suction part of the other gear element. - the arrangement of the channels and the non-concentricity of the stator ring make it possible to move it in such a way that either the engine's absorption capacity is increased, thereby increasing the pumping power reduced (for high torque), or the pump power is increased, while the engine's displacement capacity is reduced (for high speed). • 2. Continuously variable hydrostatic compact transmission for bicycles according to claim 1, characterized in that - both the outer and inner rotor are connected to the drive element and can therefore take over the function of the pump. 3. Continuously variable hydrostatic compact transmission for bicycles according to claim 1 and 2, characterized in that - the stator ring can be adjusted both manually during operation and self-regulating by pressure build-up, whereby the preload of the spring, which is necessary to build up pressure and can be adjusted during operation. Herold Marc-Rene Geiser · „, * „.' »&iacgr;. *. #Hydrocarbon compact transmission for bicycles 4. Continuously variable hydrostatic compact transmission for bicycles according to claims 1-3, characterized in that - the transmission is designed in such a way that it can be used for bicycles and other lightweight vehicles; in particular, it is fitted directly onto the (freewheel) hub of a normal rear wheel for bicycles or can be screwed. 5. Continuously adjustable hydrostatic compact transmission for bicycles according to claims 1-4, characterized in that - it is installed directly into the hub and thus functions as a stepless, automatic hub gear. 6. Continuously adjustable hydrostatic compact transmission for bicycles according to claims 1-5, characterized in that - it can also be mounted elsewhere, e.g. on the bottom bracket. 7. Continuously adjustable hydrostatic compact transmission for bicycles according to claims 1-6, characterized in that - two nested stator rings that can be controlled separately are used, which increases the efficiency of the pump in particular. . . 8. Continuously adjustable hydrostatic compact transmission for bicycles according to claims 1-7, characterized in that - axial piston pumps/motors can also be used instead of hill cell pumps/motors.