RU2044196C1 - Self-adjusted holonomic stepless continuously operating variator - Google Patents

Abstract

FIELD: mechanical engineering. SUBSTANCE: variator has driving engine, generator, two differential mechanisms, and planet gear connection with a given gear ration which couples the mechanisms. The generator power is a part of the driving engine power. EFFECT: improved design. 5 dwg, 3 tbl

Description

 The invention relates to mechanical engineering and can be used in vehicles, machine tools, as well as in other systems and objects where an automatic smooth change in the speed of the driven shaft depending on the moment of load on it at a constant speed of the drive motor is required.

 Known pulse variator containing drive and driven shafts, solar, wheel, carrier with satellites, freewheel mechanism (MCX) and an eccentric with connecting rods [1] Its disadvantages: uneven travel of the driven shaft, low durability associated with the use of freewheel roller clutches, speed limit up to 1000 rpm, lack of self-regulation.

Known friction variator containing drive and driven shafts, carrier, carrying satellites rigidly connected with cones, central wheel and ring [2]
The disadvantages of the friction variator are high pressures on the shafts and bearings associated with the use of friction forces for transmitting torque, the rigidity of the transmission characteristics, low durability and low efficiency due to geometric slip in the contact zones, limitations on the transmitted power, lack of self-adjustment.

Known hydromechanical gearbox (hydraulic transmission), containing friction clutches, a mechanical gearbox, three paddle wheels, a working fluid (liquid), pumps, pipelines [3]
The disadvantages of the known hydraulic transmission are: increased mass, low efficiency, dependent on the gear ratio, low average engine power during acceleration of the vehicle, although it is slightly higher than during acceleration using a gearbox.

 The disadvantages of hydraulic transmission should also include the lack of the possibility of smooth self-regulation of the gear ratio.

 In order to increase efficiency and reliability, a smooth set of speed, the possibility of organizing self-regulation of the CVT gear ratio depending on the dynamics of the vehicle and the track profile, reducing fuel consumption and the emission of harmful exhaust gases during acceleration, simplifying vehicle control, and also increasing engine life and transmissions by improving their dynamics, increasing the resource of the brake system due to the possibility of smooth engine braking, the proposed self-regulating The second holonomic continuously variable variator (mechanical torque transformer) is completely gear-mounted and contains two differential mechanisms, one of the same links of which are interconnected by a planetary gear link with a certain gear ratio, with the drive of which the drive motor is connected, and the other of the same name are rigidly connected among themselves, one of the third links of the same name is rigidly connected to the rack, another such link is connected to the shaft of an electric generator a, whose power is only part of the power of the drive motor.

 When using the specified variator, it becomes possible to accelerate the vehicle at full engine power, the rotational speed of which is almost constant at high engine efficiency, low fuel consumption and its more complete combustion. Acceleration is performed smoothly without shifting the gear lever, which is available on most vehicles, which simplifies management and leads to an increase in engine and transmission life, as their dynamics improves. The resource of the brake system is also increased, since it becomes possible to smoothly brake the engine.

 The acceleration time of the vehicle using the proposed variator is reduced by about 3-4 times compared with the acceleration time when using a standard gearbox or hydraulic transmission.

 When using the proposed variator, the number of controls is equal to the number of controls of serial vehicles, except that the gear lever is only needed to organize reverse gear and the neutral position necessary when starting the engine and coasting.

, которое равно передаточному отношению i

, в свою очередь равному

(см. фиг. 1). Графики представлены в относительных единицах, для сравнения здесь же представлены те же зависимости для механизма без планетарной связи между коронами (см. фиг. 2), но при прочих равных условиях; на фиг. 4 графики функций n_вых, n_вх, i_вар, N_{вых.мех.} в зависимости от изменения момента нагрузки на ведомом валу вариатора при различных значениях передаточного отношения между коронами К₁ и К₂ дифференциальных механизмов, снятые экспериментальным путем. Экспериментальные данные приведены в таблицах.In FIG. 1 is a kinematic diagram of a self-regulating holonomic continuously variable continuously variable variator (mechanical torque transformer); in FIG. 2 kinematic diagram of a known mechanism, but without a planetary connection between the crowns K ₁ and K ₂ ; in FIG. 3 the nature of the dependence of n _o , n _in , i _var , N _o.mech. from changes in the load moment on the driven shaft of the variator with the gear ratio between the crowns K ₁ and K _{2 of the} differential mechanisms i

which is equal to gear ratio i

in turn equal to

(see Fig. 1). The graphs are presented in relative units, for comparison, the same dependencies for a mechanism without a planetary connection between crowns are presented here (see Fig. 2), but ceteris paribus; in FIG. 4 graphs of functions n _o , n _o , i _var , N _o.mech. depending on the change in the load moment on the driven shaft of the variator at various values of the gear ratio between the crowns K ₁ and K _{2 of the} differential mechanisms, taken experimentally. The experimental data are given in the tables.

In FIG. 5 shows graphs of the functions of power developed by the engine N ₁ f ₁ (t); N _{1 av} ; V ₁ f ₂ (t); V _{1 cf} f ₂ (t) during acceleration of the vehicle using a speed gearbox, as well as graphs of the functions of engine power and speed N ₂ f ₃ (t); V ₂ f ₄ (t) during acceleration of the vehicle using the proposed variator.

Consider the kinematic diagram of a self-regulating holonomic continuously variable variator of continuous action (a mechanical moment transformer), shown in FIG. 1. It should be noted that in FIG. Figure 1 shows one of the possible kinematic schemes of the proposed variator, namely, a scheme with combined (rigidly connected) carriers h ₁ and h _{2 of} differential mechanisms, schemes with combined solar wheels or with combined crowns are also possible.

An internal combustion engine or any other engine rotates the drive (input) shaft 1, which is a planet carrier h ₃ planetary connection between the crowns 2 (K ₁ ) and 3 (K ₂ ) of the same differential mechanisms. Shaft 1 (carrier h ₃ ) is freely and coaxially mounted on the main axis of the mechanism. Axle 4 is freely installed in carrier h ₃ , at the ends of which satellites 5 and 6 are rigidly mounted, which mesh with gears 7 and 8, respectively, coaxially and rigidly mounted on crowns 2 and 3 of differential mechanisms.

At the ends of axis 9, the carriers 10 (h ₁ ) and 11 (h ₂ ) of the differential mechanisms are rigidly mounted. Satellites 12 are freely mounted on the axes of carrier 10, which engage, on the one hand, with a sun wheel 13 (C ₁ ) rigidly mounted on a shaft 14, at the other end of which an electric generator 15 is installed, and, on the other hand, satellites 12 are in engagement with the crown 2.

Satellites 16 are freely mounted on the axles of the carrier 11 (h ₂ ), engaging on the one hand with the crown 3, and, on the other hand, with the sun wheel 17 (C ₂ ), rigidly mounted on the shaft 18. The other end of the shaft 18 is rigidly fixed to rack 19.

 On the crown 3, a gear wheel 20 is rigidly and coaxially mounted, which is the driven (output) shaft of the variator.

 Self-regulating holonomic continuously variable CVT operates as follows.

 The internal combustion engine (or any other engine) operates in the optimal mode from the point of view of fuel consumption, power output and completeness of fuel combustion at a practically constant speed of rotation of the drive shaft 1 of the variator.

 Rotation from the drive shaft 1 is transmitted through satellites 5 and 6 to the crowns 2 and 3 of the differential mechanisms via gears 7 and 8, respectively. From the gear wheel 8, the rotation is transmitted through the crown 3 to the driven shaft 20 of the variator. Since the sun wheel 17 is rigidly locked to the stand 19, the movement from the crown 3 through the satellites 16 is transmitted to the carrier 11, shaft 9 and the carrier 10 of another differential mechanism.

 Rotation to the shaft 14 of the generator 15 is transmitted from two sides: on the one hand from the crown 2 through the satellite 12 to the sun wheel 13, on the other hand through the carrier 10 also to the satellite 12 and the sun wheel 13. Both movements are summed up on the shaft 14 of the generator 15.

= i

=

которое обеспечивает передачу большей части мощности от приводного двигателя с ведущего вала 1 на ведомый вал 20 вариатора, а на вал 14 генератора 15 в зависимости от нагрузки на ведомом валу вариатора передается от 0 до 25% мощности приводного двигателя.As shown by experimental verification, the optimal gear ratio from crown 2 (K ₁ ) to crown 3 (K ₂ ) (see Fig. 4) is the gear ratio i

= i

=

which provides the transfer of most of the power from the drive motor from the drive shaft 1 to the driven shaft 20 of the variator, and from 0 to 25% of the power of the drive engine is transferred to the shaft 14 of the generator 15, depending on the load on the driven shaft of the variator.

 Large moments on the driven shaft of the variator, decreasing as the vehicle accelerates, are required when inertia forces act when the vehicle accelerates or when going uphill. In this case, an increase in the rotational speed of the driven shaft of the variator occurs automatically as the load on the driven shaft of the variator decreases.

 After the vehicle accelerates, the generator stops and all the power from the drive shaft of the variator is completely transmitted to the driven shaft. The generator energy can be started through a relatively small electric motor and the freewheel again on the drive shaft of the variator. Since the operation of the generator and the electric motor during acceleration of the vehicle is short-lived, the electric machines can be made undersized, since they will not have time to overheat.

Used instruments in experimental studies:
ammeter of a direct current M4200, accuracy class 1.5, division value 0.2A, scale by 5A for measuring the current of the drive motor;
ammeter of a direct current M4200, accuracy class 1,5, division price 25 MA for measuring the generator current value;
DC voltmeter Ts4313, accuracy class 1.5, 30V scale for measuring generator voltage;
M42100 DC voltmeter at 30V, accuracy class 1.5 for measuring the supply voltage of the drive motor;
RPM meter IO-30 N44014, graduation price 2 rpm.

An MUF-8 direct current electromechanism with an output power of 10W and a supply voltage of 27V ± 10% was used as a drive motor; an MN-250 direct current electromechanism with an output power of 2.9 W and a supply voltage of 27B ± 10% was used
As a loading device, a drum with a radius of R 31 mm 0.031 m and various loads weighing up to 18 kg were used.

4. Соответственно и передаточное отношение (оптимальное) планетарной связи между коронами К₁ и К₂ дифференциальных механизмов выбрано следующим образом
i

=

≈ 4.In the experiment, differential mechanisms with the same diameters of the initial circles of the solar wheels and satellites were used, therefore, the gear ratio i

4. Accordingly, the gear ratio (optimal) of the planetary connection between the crowns K ₁ and K _{2 of the} differential mechanisms is selected as follows
i

=

≈ 4.

сведены в табл. 1 3.Measurement results for various gear ratios i

are summarized in table. thirteen.

The graphs of the functions n _in f ₁ (Mn), n _output f ₂ (Mn), i _var f ₃ (Mn), N _{output mech} f ₄ (Mn) and P _el.g f ₅ (Mn) in FIG. 3 are plotted in relative units based on experimental data.

относительно оптимального, характеристика вариатора n_вых f (Мн) становится "мягче" (см. кривые на фиг. 4). Кривая 1 показывает изменение частоты вращения ведомого вала механизма без планетарной связи между коронами К₁ и К₂; кривая 2 мощность, передаваемую механизмом без связи между коронами К₁ и К₂ при прочих равных условиях, т.е. те же дифференциальные механизмы, приводной двигатель, генератор и нагрузочный барабан (см. табл. 1); кривая 4 изменение частоты вращения ведомого вала 20 вариатора при передаточном отношении i

2,33 и изменении момента нагрузки; кривая 3 возможную передаваемую механизмом мощность при i

2,33 (см. табл. 1); кривые 5 и 6 те же зависимости, но при i

= 3,11 (см. табл. 2).From the analysis of experimental data it follows that as the gear ratio i decreases

relatively optimal, the characteristic of the variator n _output f (Mn) becomes "softer" (see the curves in Fig. 4). Curve 1 shows the change in the rotational speed of the driven shaft of the mechanism without planetary communication between the crowns K ₁ and K ₂ ; curve 2 power transmitted by the mechanism without communication between the crowns K ₁ and K ₂ ceteris paribus, i.e. the same differential mechanisms, a drive motor, a generator and a loading drum (see table. 1); curve 4 change in the speed of the driven shaft 20 of the variator with a gear ratio i

2.33 and change in load moment; curve 3 possible power transmitted by the mechanism at i

2.33 (see table. 1); curves 5 and 6 are the same dependences, but for i

= 3.11 (see table. 2).

3,858. На фиг. 4 эти зависимости не показаны, но они близки к данным для i

4.In the table. 2 shows the data for i

3,858. In FIG. 4 these dependencies are not shown, but they are close to the data for i

4.

выше оптимального значения характеристика вариатора n_вых f (Мн) становится жестче и может достигать значений, когда варьирования частоты вращения ведомого вала не происходит. Например, сравните на фиг. 4 кривую n_вх f₁ (Мн) и кривую 7, соответствующую i

= 8,32. Они эквидистантны, генератор в работе вариатора не участвует, варьирования передаточного отношения вариатора не происходит (см. табл. 3).With increasing i

above the optimum value, the variator characteristic n _output f (Mn) becomes stiffer and can reach values when the output shaft speed does not vary. For example, compare in FIG. 4 curve n _bx f ₁ (Mn) and curve 7 corresponding to i

= 8.32. They are equidistant, the generator does not participate in the operation of the variator, and there is no variation in the gear ratio of the variator (see Table 3).

From the point of view of efficiency, one of the differential mechanisms can be attributed to option A _hb ^a (approximate efficiency is 0.99), and the other to option A _ba ^h (approximate efficiency 0.98).

In the direct transmission mode, when the planetary connection practically does not work, and the corona K ₁ and K ₂ rotate approximately synchronously (the generator is standing at the same time). The efficiency of the variator is determined by: the efficiency _var 0.99 ^. 0.980.97.

 In the vehicle acceleration mode, the estimated efficiency of the variator will be determined by two power flows: the first up to 75% of the power of the drive motor will be transmitted from the efficiency determined above and equal to 0.97. A second power stream of up to 25% of the power of the drive motor will be transmitted through the channel engine generator, the efficiency of which should be considered 0.9 for each. Then the variator efficiency at the maximum gear ratio will be determined: 75% of the power will have a loss of 0.03; 25% power loss 1-0.9 ˙ 0.90.19.

Total losses are determined by:
0.75 ˙ 0.03 + 0.25 ˙ 0.19
0.0225 + 0.0475 0.07. The efficiency of the variator during acceleration of the vehicle (when the generator channel is activated) will be no worse than 1 0.07 0.93.

 The reliability of the proposed variator will be higher than that of a hydromechanical transmission, since its design is simple and contains a small number of elements, namely gears and bearings, the failure rate of which is low per unit time, in contrast to the hydromechanical transmission, which is also a moment transformer where there are three paddle wheels, clutches, gearbox, pumps and a number of mechanical elements. The hydraulic transmission system requires a high degree of tightness.

 Fuel economy is achieved due to the fact that the vehicle is accelerated at full engine power and more complete combustion, therefore, approximately 3-4 times faster (see Fig. 6) than during acceleration using a speed gearbox or hydraulic transmission, where the average engine power is 2 3 times less than the available engine power, and the gear shift leads to increased fuel consumption during acceleration and poor combustion, which in turn leads to the emission of a large amount of harmful exhaust gases.

 In addition, since the proposed variator uses the full engine power, and with a gearbox or hydraulic transmission only part of the available engine power (about 40%), engine power can be significantly reduced, which in turn leads to a decrease in fuel consumption and engine mass .

 Simplification of vehicle control is achieved due to the fact that the gearbox requires nineteen different actions of the driver to accelerate it, while to accelerate the vehicle using the proposed variator, it is only necessary to depress the clutch, engage forward gear, press the gas pedal (all the way to the stop) ) and release the clutch (total four movements). Further acceleration of the vehicle will be automatic and smooth.

 The shift lever must have three positions: forward, reverse and neutral.

 The absence of frequent gearbox shifts leads to improved dynamics of the engine and transmission, and this in turn increases their resource.

 In addition, the proposed variator increases the resource of the brake system of the vehicle, as it becomes possible to smooth engine braking when the fuel supply is reset.

Claims (1)

 Self-regulating holonomic continuously variable variator with drive and driven shafts, characterized in that it contains two differential mechanisms, one of the same links of which including a link connected to the driven shaft of the variator, are interconnected by a planetary gear link with a certain gear ratio, with the driver of which the drive motor is connected, other links of the same name are rigidly interconnected, one of the third links of the same name is rigidly connected to the rack, and the other is the link is connected to the shaft of the generator, the power of which is only part of the power of the drive motor.

Images