WO1995001522A2

WO1995001522A2 - Drive design using a continuously variable transmission

Info

Publication number: WO1995001522A2
Application number: PCT/DE1994/000739
Authority: WO
Inventors: Harald Von Hacht
Original assignee: Harald Von Hacht
Priority date: 1993-06-30
Filing date: 1994-06-29
Publication date: 1995-01-12
Also published as: WO1995001522A3

Abstract

The object of the drive design is to create a driving engine which can rotate at a constant working speed of rotation and whose output speed of rotation may be continuously controlled at will by means of a newly developed flange-mounted transmission. For that purpose, parts of a transmission equipped with planetary wheels are fixed in a hitherto unknown manner to parts of a servomachine (3, 6.1, 11), in particular where the rotation of the transmission may be utilised, i.e. where the difference in the speed of rotation in the same direction of two parts of the transmission is always substantially smaller than the difference between the input (1) and the output (10) of the transmission. If said range of immanent speeds of rotation is influenced through braking (13) by means of a servomachine, the output shaft (10) begins to rotate forward or backward depending on the extent and type of the engagement. The invention has applications in all cases in which differential speeds of rotation need to be compensated, in particular in vehicles, machines and wind power generators.

Description

Drive concept using a continuously variable transmission

description

In the sense of this invention, as 'vegetative', the drive concept (VA concept) for all drives controllable by gears is characterized in that, in contrast to all previous drive forms, the drive machine is no longer controlled directly, that is to say by motor, but rather can work constantly at their optimal speed with maximum torque and thus with the best efficiency. Rather, the control takes place via a continuously variable and continuously reversible transmission, which is the subject of this invention. This transmission, in which a gear wheel never has to be shifted, additionally enables a continuous and leiltungsabhangiye maximum acceleration.

Conventional drive systems are usually characterized in that the power-generating unit is controlled to vary the output power, the intermediate gearbox having the power to regulate the power transmission in such a way that on the one hand starting is possible in the first place and on the other hand in the state üuu Laulens the best possible efficiency between performance generation and performance acceptance is achieved. The disadvantages of these arrangements are that the drive unit cannot be optimally designed and, on the other hand, once it has been designed, it can rarely be operated at the speed corresponding to the optimum efficiency. All previous developments of continuously variable transmissions, such as in the scriptures

US 2,147,528, US 3,653.27V,

DP 653 589, DP 2317482,

US 2,308,547, DP 2410342,

DE 859999 DP 2530185,

US 3299739, DE 2650152,

US 3,431,798, DE 3712659 AI,

DP 2215396, WO 91/00968

shown, for example, the Aπtnebsmaschine never offer the opportunity to run at a constant speed of their best efficiency to be able to. Furthermore, the efficiency of the hydraulic speed control mechanisms is also still very poor because, contrary to the present invention, the converter turbines often have to be accelerated from a standing position. A simple reversal of the direction of rotation is almost never mentioned. Due to their complexity, many constructions convey increased vulnerability. Many constructions do not allow an idle position in the output even without an additional component.

The invention had for its object to develop a servomechanical drive device with the least possible technical effort and good efficiency, the translation of which can be regulated continuously. The present invention is based on the fact that the drive unit itself can always be kept in the optimal speed range even by internal automatic control, as is already well known, and that the power transmission can be varied via the continuously variable transmission, which is the subject of this invention. In the same way, it would be possible to put the speed constant on the side of the power consumption if the drive unit (e.g. in wind turbines) should work with changing speed.

In analogy to biological processes, the arrangement shown here is characterized by the term 'vegetative', since the control of the power consumption is no longer carried out by direct motoric influencing of the drive machine, but indirectly by exclusively controlling the inherent "speed ratio" inherent in this transmission.

The present invention includes Devices (converters) which are suitable for controlling all types of gear formations which have planetary gears between the input and output gear (e.g. also differentials) in a previously unknown manner.

The mechanical, geometrical and mathematical / physical principles of planetary gear arrangements are assumed to be known, although the speed behavior still allows new knowledge.

Previously known planetary gear systems work in such a way that an input force is passively converted in accordance with the specified design of the system. It can normally be assumed that one of the three essential, moving parts, namely sun gear (S), planet carrier (PT) with planet gears and planet gear (U), remains fixed. During operation, a "system-internal speed ratio" is established between the two moving parts. for the simplest planetary gear constellation Hureh the following Formula is reproduced:

Therein n is the respective speed in min ^-1 and Z is the respective number of gear teeth.

If the planetary gear is fixed in such a "stable" planetary gear set, the "system-inherent speed ratio" is in the range of approx. 0.4: 1 with the same direction of rotation of the planet carrier and sun gear. A possibly desired variation of this speed ratio by changing the gear sizes due to design restrictions is only possible to a very limited extent. If, on the other hand, the planet carrier is locked, the same formula results in a "system-inherent speed ratio" of approx. 0.5: 1 between the planet gear and the sun gear. Only the directions of rotation of the planet gear and sun gear can now be opposite.

However, contrary to the above assumptions, if all parts in a planetary gear system are freely movable, the system has an unstable speed behavior.

However, the speed ratio of two parts of the simplest planetary gear set can be influenced more if e.g. several planetary gears are connected in series in such a way that all sun gears rotate on one shaft and the planet gears are connected to the planet carrier of the next set (see Fig. II).

With the "system-inherent speed ratio", the invention technically offers the possibility that the full speed difference existing between these does not have to be reduced for the synchronization between input and output, but only a speed difference between the moving parts of the servo gearbox that is more than half lower.

Since the overall efficiency of the new VA concept on which the invention is based essentially depends on the efficiency of the technology regulating the speed, the speed difference to be influenced between two parts should always be as small as technically possible. It follows that on the one hand the drive machine can be controlled automatically at a speed that enables the best efficiency according to the design calculation and on the other hand, thanks to the 'vegetative' drive, any speed can now be steplessly removed. The present invention is characterized in that to stabilize the speed behavior with free movement of all parts in the planetary system is actively intervened in such a way that a. when starting the system from a standstill (ie a part is fixed) the "system-inherent speed ratio" between then two moving parts is changed with the effect that the third part starts to move, back and forth, depending on whether the above speed ratio is reduced or increased, b. all conceivable while running by continuously changing this speed ratio in the positive and negative sense

Changes in the running state (accelerating, decelerating, changing the direction of rotation) are brought about. The third part remains in the rest position whenever there is a "system-inherent speed ratio" between the other two parts. At a constant input speed, this is the only way to achieve a continuously variable output speed in a technically sensible manner.

The active intervention according to the invention in the sense of a stepless regulation thus takes place by controlling the change in the speed relation via stepless acceleration or deceleration of one part of the planetary gear system with respect to another.

This can be done by control mechanisms of various types, e.g.

Torque converter, viscous coupling or current machine, which are firmly connected to parts of the transmission, as shown in FIGS. I to XII. The viscous clutches or brakes can and should always be thermally controlled.

It is essential for the invention that active intervention is made in the planetary gear system, which is movable in all parts, and this applies to all degrees of freedom of the respective system of planetary gear constructions.

I to XII show examples of ways in which different control mechanisms can be structurally connected to planetary gear arrangements in different ways.

For all arrangements applies that the torque introduced via a shaft is divided into at least two strands, namely - In Fig. I and II in two hydraulic lines,

III to X each in a mechanical and hydraulic train,

- In Figs. XI and XII in each case a mechanical and an electrical strand.

The introduction of the force must always take place at 1 in FIGS. I to VI; in FIGS. VII to XII the flow of force can be carried out both from 1 to 10 and from 10 to 1. I, II, III, IV and VI of the rotating converter housing 2 can be provided with centrifugal valves 14 for controlling the oil filling. With the standing converter in

V is the oil control to perform stationary. A centrifugal clutch or lock-up clutch, which engages as soon as there is synchronous operation, is useful for all gearbox configurations.

I, II and VI can be reversed with the help of a blocking brake band 13 in Fig. III, IV, V, VII, VIII, X, XI and XII a controllable braking must be selected, a viscous brake or a e.g. in a motor vehicle slip clutch controllable via the brake pedal pressure of a known type. A stepless change in speed both in the forward and reverse is shown in Fig. VI. If it is not necessary to reverse the direction of rotation in the output, any connection of parts of the speed converter with parts of the planetary gear set is possible (see Fig. IX), but with the simplest possible reversal, a portion of the torque should lead over the planet carrier, which must then be braked.

The use of a VA drive in a motor vehicle offers the following advantages:

1. The drive machine can always be operated constantly at the most favorable speed without the need for direct influence.

2. The efficiency of the prime mover can thus be maximized, its thermal budget is uniform:.

3. A simplified design is also possible with internal combustion engines.

4. The necessary energy input is reduced.

5. VA systems are environmentally friendly because of the exhaust gas composition

is easier to check, predictable and controllable. 6. Due to their comparatively simple construction, VA drives are cheaper to manufacture and require less maintenance because they require fewer components.

7. If necessary, optimal acceleration up to synchronous operation in the transmission is also possible, i.e. with normal translation in

Differential of motor vehicles up to a speed of approx. 100 km / h.

8. Driving vehicles is made easier.

9. The engine can be designed more effectively in terms of energy consumption and pollutant emissions: For the

Only the speed of the maximum torque is important for the motor design, i.e. it doesn't require as many technical compromises as with conventional drive systems. All calculation criteria can be related to this speed. The idle speed can be neglected, the speeds between the idle speed and the speed of the maximum torque are not relevant and speeds above the speed of the maximum torque may or may not occur.

10. New drives are now entering the area of technical and economic feasibility.

11. The translation in the vehicle can be designed so that the synchronous operation in the new transmission occurs when a possibly legally prescribed final speed has been reached.

12. In order to give vehicles a higher speed than the synchronous operation of the VA drive allows, while accepting poorer efficiency, the engine speed can also be increased in order to utilize the power reserve (in kW or PS) of the engine.

Designations in Figs. I to XII

1 drive shaft

2 converter housings

3 pump

4 pump shaft

5.1 planetary gear 1

5.2 planet gear 2

6.1 Turbine 1

6.2 Turbine 2

7.1 Turbine shaft 1

7.2 Turbine shaft 2

8.1 Planet carrier 1

8.2 Planet carrier 2

9.1 5notor 1

9.2 Sun gear 2

10 output shaft

11 guide wheel

12 freewheel

13 brake

14 centrifugal valve

15 oil channel

16 differential

17 gear

18 gear

19 gear

20 gear

Claims

Patent claims

(1) The invention relates to a drive system referred to as 'vegetative', characterized in that the ratio between input and output speed is regulated via a continuously variable servo-mechanical transmission, with one of the two speeds being independent of the load to achieve optimal efficiency can be kept constant. The continuous change of the other speed, which is not kept constant (also starting at n = 0), is carried out by consciously changing the speed ratio inherent in the planetary gear system active in the servo gearbox, hereinafter referred to as "system-immanent", between two of the all movable parts of this planetary gear arrangement by means of fixed servo machines connected to parts of this arrangement (control mechanisms such as hydraulic clutch, hydraulic converter, viscous clutch, electrical clutch, mechanical slip clutch), whereby the third part of the planetary gear arrangement is set in rotation, the speed and direction of rotation depending on the type of change in the speed ratio of the the other two parts as well as the speed range in which this consciously induced change takes place.

Reversing the direction of rotation, which is only possible if the planet carrier can be braked individually, is achieved by reducing the planet carrier speed, if necessary to a standstill.

In order to always ensure a power balance between the power generated and the power consumed, feedback is provided between the servo gearbox and the drive machine.

The invention involves the use of the specific "system-inherent speed ratio of plate wheel systems with the result that when the drive shaft is rotating and the output is stationary, two elements in the servo-mechanical transmission can move in the same direction of rotation with possibly less than 50% speed difference. A complete speed adjustment between input and and output through synchronization of these two elements means a significant increase in efficiency compared to all previously known designs. (2) Arrangement according to claim 1, characterized in that the "system-inherent speed ratio" to be synchronized in the servo machine can be significantly influenced in the planetary gear system by expanding the planetary gear. According to Fig. II, the speed difference in the converter between the pump wheel and the turbine, which influences the efficiency, is reduced to less than 1: 0.6. Here, for example, the turbine 6.1 drives both sun gears 9.1 and 9.2 and the turbine 6.2 drives the first planet carrier 8.1, which in turn drives the planet carrier 8 via the planetary gear 5.1.

2 drives. In this way, the efficiency in the servo machine can be significantly improved very easily.

(3) Arrangement according to claims 1 and 2, characterized in that easier torque control is possible when the housing according to FIG. V is stationary.

(4) Arrangement according to claims 1 to 3, characterized in that a converter structure with a pump, turbine and stator according to FIG. VI is possible, in which a stepless change in speed after reversing the direction of rotation is now also possible.

(5) Arrangement according to claims 1 and 2, characterized in that in the embodiments according to FIGS. VII, VIII, IX and

Viscose machines are also thermally controlled to facilitate continuous traction. In these designs, the direction of the force flow through the servo-mechanical transmission is not fixed.

(6) Arrangement according to claim 1, characterized in that

In an arrangement according to FIG.