RU2679352C1 - Planetary gearbox - Google Patents

Abstract

FIELD: machine building.SUBSTANCE: invention relates to the planetary gearboxes (PGB). Five-speed PGB with two degrees of freedom contains four single-row planetary mechanisms, friction clutch and four brakes. Gearbox input shaft is connected to the first and second planetary mechanisms sun gears and through to friction clutch to the planetary mechanism epicyclic gear. Second planetary gear epicyclic gear is connected to the first planetary gear carrier and to the third planetary gear sun gear. Second planetary mechanism carrier is connected to the third and fourth planetary mechanisms common carrier and to the gearbox output shaft. Third planetary mechanism epicyclic gear is associated with the fourth planetary mechanism epicyclic gear. On the first, second, third, fourth planetary mechanisms epicyclic gears and on the fourth planetary mechanism sun gear, the brakes are installed.EFFECT: enabling the gearbox design simplification.1 cl, 1 dwg, 1 tbl

Description

The invention relates to transport machinery, in particular to gearboxes used in transmissions of vehicles.

A planetary gearbox (PKP) contains a housing, input and output shafts, four single-row planetary gears, a friction clutch and four brakes. The input shaft of the gearbox is connected to the sun gears of the first and second planetary gears and through a friction clutch with the epicyclic gear of the first planetary gear. The epicyclic gear of the second planetary gear is connected with the carrier of the first planetary gear and with the sun gear of the third planetary gear. The carrier of the second planetary gear is connected with the common carrier of the third and fourth planetary gears and with the output shaft of the gearbox. The epicyclic gear of the third planetary gear is connected to the epicyclic gear of the fourth planetary gear. Brakes are installed on the epicyclic gears of the first, second, third, fourth planetary gears and on the sun gear of the fourth planetary gear.

The planetary gearbox has four forward gears and one reverse gear. Each gear engages one control. This embodiment of the gearbox simplifies its design and gear shifting control, makes it compact, improves the breakdown of gear ratios, and improves reliability and manufacturability.

Known planetary gearbox used in the transmission of tracked vehicles VGM-569, VGM-352, VGM-355, VGM 5951, VGM 5955 (1). The specified control panel contains a housing, input and output shafts, four planetary gears, two friction clutches and four brakes. The input shaft of the control panel is connected to the first sun gear of the first planetary gear, the second sun gear of which is connected to the sun gears of the third and fourth planetary gears and, through the first friction clutch, to the carrier of the first planetary gear; the carrier of the second planetary mechanism is connected with the carriers of the third, fourth planetary mechanisms and with the output shaft of the control panel, and through the second friction clutch with the sun gear of the same planetary mechanism; epicyclic gears of the second and third planetary mechanisms are interconnected; brakes are installed on the carrier of the first planetary gear, on the sun gear of the second planetary gear, and also on the epicyclic gears of the third and fourth planetary gears.

When pairing the two controls, four forward gears and four reverse gears are obtained.

The specified gearbox has several disadvantages:

complex construction, which is due to the use of paired satellites in the first and second planetary mechanisms. In addition, the first planetary mechanism is a mechanism with external gearing, and the second is a mechanism with mixed gearing. Thus, of the entire design of the control panel, only two planetary mechanisms (the third and fourth) are single-row. As is known (4), single-row planetary mechanisms are the simplest in design and technological in manufacturing, the most balanced and have a higher efficiency;

the difficulty of controlling the gearbox, since in order to receive each gear it is necessary to include two control elements;

low average speeds, low profitability and throttle response, as well as insufficient use of engine power due to unsuccessful breakdown of gear ratios - the progression denominator is not a constant: q _I = 1.96; q _II = 1.89; q _III = 1.68. To solve these problems, in the complex, the breakdown of the gears in the kinematic range of the gearboxes of vehicles must be done geometrically (1, 3, 4);

insufficient reliability due to the presence of power circulation on the most running - third gear and overload of the third planetary gear. The calculations are performed according to (1);

finally, there was no need to create a planetary gearbox with three degrees of freedom, since the gear ratios specified by the traction calculation could be obtained in a planetary gearbox with two degrees of freedom with a simpler and more technological design and a gear shift control system, which is represented in the inventive planetary gearbox.

Closest to the claimed, adopted as a prototype, is the well-known planetary gearbox [Pat. 2132985 Russian Federation]. The specified control panel contains a housing, input and output shafts, four single-row planetary gears, a friction clutch and four brakes; the input shaft of the control panel is connected to the sun gears of the first and second planetary gears and through a friction clutch to the epicyclic gear of the first planetary gear, the carrier of which is connected to the epicyclic gear of the second planetary gear, which is connected to the sun gears of the third and fourth planetary gears; the carrier of the second planetary gear is connected with the carrier of the fourth planetary gear and through it with the epicyclic gear of the third planetary gear and with the output shaft of the gearbox, and brakes are installed on the epicyclic gears of the first, second and fourth planetary gears and on the carrier of the third planetary gear

In the known planetary gearbox, a kinematic range of 6.24 is obtained, which is divided into geometrical progression gears with the following gear ratios:

first gear - 6.24; second gear - 2.82; third gear - 1.68; fourth gear - 1.0; reverse gear - minus 6.24.

The disadvantages of the known planetary gearbox are:

the kinematic range of the control panel is at the lower limit of the recommended. For example, when using the well-known PKP instead of serial in hydromechanical transmissions of military tracked vehicles 569, 352, 355, 5955 and 5975 (1) with a working transformation coefficient equal to, as a rule, 1.9, adaptability coefficient 1.1 and first gear ratio 6.24 will be equal to 13.04.

In accordance with the recommendations of (2, p. 124), the optimal value of the kinematic range of multi-purpose conveyor tractors should be within 12 ... 16;

a large gap between the gear ratios of the first and second gears (the denominator of the progression is 2.2), which causes, firstly, difficulties when switching from first gear to second; secondly, it reduces the dynamic qualities of the vehicle and, thirdly, leads to an increase in fuel consumption.

According to the data published in (5), the denominator of the progression between the first and second gears is in the range of 1.78 ... 2.0;

lack of compact design, which complicates its practical application.

An object of the invention is to simplify the design of the planetary gearbox, increase its kinematic range to the maximum possible increase in traction forces in all gears by increasing the values of the gearbox external gear ratios in all gears, improving the breakdown of gear ratios, which will provide the vehicle with an increase in its mobility.

The specified technical problem is achieved by the fact that the claimed five-stage control panel with two degrees of freedom contains a housing, input and output shafts, four single-row planetary gears, a friction clutch, four brakes and, unlike the prototype, contains a common carrier of the third and fourth planetary gears, the carrier of the second the planetary mechanism is connected with the common carrier of the third and fourth planetary mechanisms, the epicyclic gears of the third and fourth planetary mechanisms are connected to each other, and on the epicyclic the gear of the third planetary gear and the brakes of the fourth planetary gear.

In FIG. 1 shows a kinematic diagram of the inventive planetary gearbox. It contains input 1 and output 2 shafts installed in housing 3, a friction clutch M _IV and four brakes - T _III, T _II , T _z.kh. and T _I. The PKP consists of four single-row planetary mechanisms (b, a, d, e). The first planetary gear (b) contains the sun gear 4, the epicyclic gear 5 and drove 6 with the satellites 7. The second planetary gear (a) contains the sun gear 8, the epicyclic gear 9 and the carrier 10 with the satellites 11. The third planetary gear (d) contains the sun the gear 12, the epicyclic gear 13 and the carrier 14 with the satellites 15. The fourth planetary gear (e) contains the sun gear 16, the epicyclic gear 17 and the carrier 14 with the satellites 18.

The input shaft 1 of the control panel is connected to the sun gears 4 of the first and 8 second planetary gears and through the friction clutch M _IV to the epicyclic gear 5 of the first planetary gear. The epicyclic gear 9 of the second planetary gear is connected to the carrier 6 of the first planetary gear and to the sun gear 12 of the third planetary gear. Drove 10 of the second planetary gear associated with a common carrier 14 of the third and fourth planetary gears and with the output shaft 2 of the gearbox. The epicyclic gear 13 of the third planetary gear is connected to the epicyclic gear 17 of the fourth planetary gear. On the epicyclic gears 5 of the first, 9 of the second, 13 of the third and 17 of the fourth planetary gears brakes are installed.

Planetary gearbox operates as follows. When you turn on the controls T _I , T _II , T _III , T _z.h. and M _IV, in accordance with Table 1, the links of planetary mechanisms are connected in a kinematic scheme defined for each transmission, as a result of which the power from the input shaft 1 to the output shaft 2 is transmitted with the corresponding gear ratio.

To obtain the first gear include the brake T _I , which ensures the stop of the sun gear 16 of the fourth planetary mechanism. The power flow from the input shaft 1 through the sun gear 8 is transmitted to the satellites 11, where it is divided into two parts. The first part of the power flow through the carrier 10 is transmitted to the output shaft 2. The second part of the power flow is transmitted to the epicyclic gear 9, the sun gear 12, the satellites 15, the carrier 14 and to the output shaft 2, where it merges with the first part into one stream.

In second gear, brake T _II is engaged, stopping the epicyclic gear 9. Power flow from the input shaft 1 through the sun gear 8, satellites 11 and carrier 10 is transmitted to the output shaft 2.

In third gear, the brake T _III is engaged, stopping the epicyclic gear 5. The power flow from the input shaft 1 is divided into two parts. The first part of the power flow through the sun gear 8 and the satellites 11 is transmitted to the carrier 10. The second part of the power flow is transmitted through the sun gear 4, the satellites 7, carrier 6, the epicyclic gear 9, the satellites 11 to the carrier 10, where both flows merge into one stream, which is transmitted to the output shaft 2.

In fourth gear include clutch M _IV . In this case, the first and second planetary gears of the control panel are blocked and the gearbox gives direct transmission to the output shaft 2.

In reverse gear include brake T _z.kh. , stopping the epicyclic gear 13. The power flow from the input shaft 1 through the sun gear 8 is transmitted to the satellites 11, where it is divided into two parts. The first part of the power flow through the carrier 10 is transmitted to the output shaft 2. The second part of the power flow is transmitted through the epicyclic gear 9 to the sun gear 12, satellites 15 and then through the carrier 14 to the output shaft 2, where it merges with the first part into one power stream.

The design features of the claimed planetary gearbox are:

in the claimed PKP, in contrast to the prototype, not four but three carriers (the carrier of the third and fourth planetary gears is common), the epicyclic gears of the third and fourth planetary gears are connected to each other, which makes the design of the PKP more compact;

increased kinematic range of the control panel and, as a result, the transmission. So, for example, when using the inventive PKP in hydromechanical transmissions of VGM 569, 352, 355, 5955 and 5975 (1) with a working coefficient of hydrodynamic transformer 1.9, coefficient of adaptability of the engine 1.1 and gear ratio of the first gear 6.48 (table 1 ), the kinematic range of the transmission will be 13.54;

the kinematic range of gear ratios is divided exponentially (table 1), which will provide the vehicle with an improvement in its following operational properties: higher average speeds, improved throttle response, faster acceleration, better utilization of engine traction, improved fuel economy and improved conditions driver work;

increased gear ratios in all gears compared with the prototype, which will provide the vehicle with an increase in traction and throughput and, as a result, increased mobility;

the gap between the gear ratios of the first and second gears has been reduced (the progression denominator has been reduced from 2.2 to 2.0 - table 1, which will provide the vehicle with a reliable switch from first to second gear, improve the dynamic qualities of the vehicle and reduce fuel consumption;

there is no power circulation in forward gears;

under load on the running gears (second and third), the minimum number of planetary gears works (Fig. 1), which will positively affect the efficiency gearboxes:

- first gear - three (a, d, e); - second gear - one (a); - third gear - two (a, b); - reverse gear - two (a, d).

INFORMATION SOURCES

1. Tracked vehicle GM-569 and its modifications. Technical description and instruction manual. - M .: Military Publishing House, 1985, p. 296.

2. Antonov A.S. Power transmission of wheeled and tracked vehicles. Theory and calculation. 2nd edition, revised and supplemented. - L .: Engineering, 1975, p. 480.

3. Antonov A.S. Armeysky tracked vehicles. Part 1. - M .: Military Publishing House, 1973, p. 397.

4. Krasnenkov V.I., Vashets A.D. Design of planetary mechanisms of transport machines. - M.: Mechanical Engineering, 1986, p. 271.

5. The development trend of special wheeled chassis and military tractors. GABTU MO RF, 21 research and testing institute. - Bronnitsy, 2007, p. 41.

Claims (1)

A planetary gearbox comprising a housing, input and output shafts, four single-row planetary gears, a friction clutch and four brakes, the input shaft of which is connected via an friction clutch to the epicyclic gear of the first planetary gear and sun gears of the first and second planetary gears, the epicyclic gear of the second planetary gear connected to the sun gear of the third planetary mechanism, the carrier of the second planetary mechanism connected to the carrier of the fourth planetary mechanism and the output shaft, and on the epicyclic gears of the first, second and fourth planetary mechanisms, brakes are installed, characterized in that the third and fourth planetary mechanisms contain a common carrier, the carrier of the second planetary mechanism is connected with a common carrier of the third and fourth planetary mechanisms and with the output shaft of the gearbox, epicyclic gears of the third and fourth planetary gears are connected to each other, and on the epicyclic gear of the third planetary gear and on the sun gear of the fourth planetary gear set brakes.

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