RU2551052C2 - Transmission with hydraulic interaxle and interwheel differential links with automatically controlled interlocking modes for high cross-country capacity vehicle - Google Patents

Abstract

FIELD: transport.

SUBSTANCE: invention relates to automotive industry and can be used for development of transmissions for wheels vehicles of high cross-country capacity. Transmission with drive axles of portal type and stiff kinematics of all four half-axles and gearbox secondary shaft, wheel misaligned reduction gearboxes with single-row output planetary mechanisms with drive crown gears engaged with half-axles while sun gears are engaged with hydraulic machines shafts, hydraulic machine housings being rigidly coupled with those of wheel reduction gears. Working chambers of every drive axle are communicated via reverse slide valve with high-and low-pressure lines provided with boost system. High-pressure line incorporates fluid interlocking throttling mechanisms with stepwise drag variation. Note here that self-locking of ACS at vehicle turn depends on turn angle, front controlled wheel rpm and torque differences which allows actuation of one of said two self-locking modes or complete interlocking of interwheel differential gearing. Said lines include selective valves communicating pressure chambers of higher-load hydraulic machines of front and rear wheels with interaxle high-pressure line with electrically-controlled fluid two-mode locking mechanism.

EFFECT: higher mobility, cross-country capacity and efficiency.

11 cl, 13 dwg

Description

 The invention relates to the field of transport engineering and can be used in the construction of wheeled vehicles with increased cross-country ability, mainly for working in off-road conditions.

The objectives of the invention are to increase the maneuverability, maneuverability and efficiency of wheeled all-wheel drive vehicles and reduce the dynamic load of its power transmission in off-road conditions, as well as providing the necessary maneuverability and the ability to start the engine when towing the vehicle.

Off-road traffic conditions are characterized by greater curvature of the trajectory than during traffic, more frequent change of direction of movement and quickly varying coefficients of adhesion and rolling resistance of the wheels, which requires a reduction in the used speeds and increased steering angles of the front steering wheels of the ATS.

The possibility of increasing the maneuverability and cross-country ability of the ATS largely depends on the characteristics of the partial blocking modes of the used cross-axle differentials (MKD). In modern automatic telephone exchanges (4k4), self-blocking MCDs are mainly used. The blocking moment of these MCDs depends on either the transmitted torque or the difference in wheel speed.

The main disadvantage of the former for off-road traffic conditions is their constant or varying in narrow limits blocking coefficient. Given with a margin (for the most difficult driving conditions) with increased angles of rotation of the front wheels, it prevents the timely transition of the wheel drive from a synchronous (blocked) mode of rotation of the wheels to differential, especially when driving on soft ground. Under these conditions, the increased locking moment causes both an increase in the lateral drive of the front wheels, and a traction overload of the "lagging" (internal) wheels and their prohibitive slipping. As a result, the minimum turning radius and energy loss during slipping are increased, and maneuverability and economy are reduced. The higher the blocking coefficient, the more the total thrust of the wheels of the drive axle in the differential drive mode decreases (in those cases when the transition to the differential mode is possible). As a result, the cross-country ability of the ATS is deteriorating when turning with small radii.

In this regard, self-locking MCDs have a potential advantage, in which the locking moments automatically change with the difference in the frequency of rotation of the wheels, and due to their reduction at large angles of rotation of the front wheels, the lateral drive of the latter is reduced, as well as slipping of the “lagging” wheels. In widely used “viscous couplings” in off-road conditions, this advantage is not feasible due to the inertia of the process of changing the viscosity of the working fluid. Self-locking differentials | 1 |, | 2 | are known, which lack this disadvantage. As a self-locking mechanism, they use a hydraulic pump, the stator and rotor of which are connected to the differential housing and one of the axle shafts, respectively, | 1 |, | 2 |. With a difference in the frequency of rotation of the wheels Δω, the frequency of relative rotation of the stator and rotor is 0.5ωΔ, and the flow of the working fluid from the hydraulic pump bypassed through a calibrated hole | 1 | or needle throttle | 2 |, is proportional to it. The moment of resistance to the mutual rotation of the stator and rotor

where C is a coefficient proportional to the coefficient of resistance of the inductor. In the self-locking differential | 1 | with “hydraulic resistance” this moment is blocking. The internal dimensions of the rotating differential housing limit the working volume of the hydraulic pump used, and therefore the limit values of the transmitted torque of the wheels and the moment of blocking the MCD, which are proportional to the weight load of the wheels. To overcome this limitation in the "gerotor" differential "Hydra-Loc" | 2 | the main part of the blocking moment is created not by the hydraulic pump, but by a hydraulic controlled friction clutch, the pressure in the working hydraulic cylinder of which is supported by the hydraulic pump, is proportional to M _ω . Thus, these differentials provide either the aforementioned dependence (1) of the blocking moment on the difference in the frequency of rotation of the wheels | 1 | or a dependence similar to it in nature | 2 |.

To reduce the moment of turning resistance and the angles of the lateral drive of the front wheels at large angles of rotation, regardless of the average value of the coefficient of adhesion of the wheels, it is necessary to reduce the value of C, if there is not a big difference in these ratios of “running” and “lagging” wheels. If their difference is significant, on the contrary, in order to exclude the traction overload of “running-in” wheels, a larger value of C is necessary. And if, in this case, “running-in” wheels are in better conditions, then at medium and small values of the rotation angles of the front wheels to reduce slipping of the “behind” wheels , you just need to lock the differential, because in this case, the moments from the difference between the tangential forces of the traction and the forces of rolling resistance are directed towards the rotation of the ATS. In addition, for the normal functioning of the anti-lock braking system (ABS) of the ATS, a full unlocking of the MCD with the start of braking is necessary.

At the same time, in devices | 1 |, | 2 | the working line of the hydraulic pump with an uncontrolled throttle is located in the channels of the rotating differential housing. It is known to install an electrically controlled valve | 3 | in such a trunk. However, the capabilities of such a valve are limited to three working positions (in the presence of two control windings), therefore, it will not be able to provide full blocking, and two self-locking modes during a stepless reset of the throttle, and full unlocking of the MCD.

A common drawback of a transmission with gear differentials is the high dynamic loads of the power transmission in full blocking mode, given the significant amount of micro- and macro-roughness of the soil surface in off-road conditions.

More simply, the problem of “multi-mode” self-locking MKD can be solved by using leading bridges with a hydrostatic differential and hydraulic cross-axle differential coupling, carried out by a hydraulic transmission, consisting of two volumetric reversible hydraulic machines, whose rotors are connected to the half-axes, and the stators - to the driven gear of the ATS | 4 main transmission |, | 5 |. Under equal conditions of movement, there is no relative rotation of the stators and rotors of the hydraulic machines and the flow of the working fluid in the discharge line of the hydraulic transmission, the pressure in the high-pressure cavities of the hydraulic machines and the torques of the wheels are the same. When turning the ATC or with a small difference in the coefficient of adhesion of the wheels, a relative rotation of the rotors relative to the stators of the hydraulic machines occurs, while the hydraulic machine of the decelerating wheel operates in pump mode, and the hydraulic machine of the accelerating wheel in motor mode.

In the device | 4 | hydraulic transmission - adjustable due to multidirectional changes in the working volume of hydraulic machines, carried out by two electromagnets with proportional control. The disadvantage of this device is, first of all, the unreliability of the design of hydraulic machines due to the large cantilever loads on the working plungers, which can lead to increased wear of the pair of plunger-rotor, when controlling the lateral movement of the cam sleeve. There is no feeding system for the suction cavities of hydraulic machines. It is difficult to ensure the proper accuracy of the system for automatically controlling the working volume of hydraulic machines by axial movement of the cam sleeve due to the large contact stresses in the contact zone of the working plungers and the supporting wave surface of the cam sleeve associated with large dry friction forces. The proposed device is not disclosed an algorithm for regulating the working volume of hydraulic machines depending on the angle of rotation of the wheels and the difference in the friction coefficients of “running” and “lagging” wheels.

A hydrovolume differential device | 5 | is known, in which the stators of two gerotor hydraulic machines are made in one block with the driven gear of the main gear, and the rotors of the hydraulic machines are mounted on the inner shafts of the axle shafts. The injection and suction cavities of the hydraulic machines through the channels inside the trunnions of the rotating stators, the annular internal grooves in the sliding supports of the fixed housing of the differential device, are connected to the electrically controlled two-position four-way spool by high and low pressure lines. In one position, it connects the corresponding working cavities of hydraulic machines, providing cross-wheel differential communication, and in another position, it disconnects them, blocking the differential connection. Unlocking it occurs automatically when the steered wheels are rotated by a sensor signal. In addition, the working cavities of each hydraulic machine are connected through the above-mentioned annular internal grooves to an electrically controlled (from the electronic control unit) two-position reverse spool. This spool provides the connection of the injection cavity of the hydraulic machine with an electrically controlled bypass valve, and the suction cavity with the reservoir of the working fluid. When changing the direction of rotation of the wheels, the working cavities of the hydraulic machines change roles and the specified spool automatically switches to another position. These bypass valves limit the pressure of the working fluid and the torques transmitted by the wheels with differential differential lock, and also make it possible to reduce the torque of one of the wheels in this mode, for example, with less traction or, by completely relieving pressure, disconnect the active wheel drive.

Since both wheels rotate synchronously with a blocked cross-axle differential connection, and the measurement of wheel torques is not provided, it is not clear how it is possible to identify a wheel with less grip in order to reduce its slipping by reducing the transmitted torque. In rectilinear motion, the effect of reducing this slipping is offset by an increase in energy losses in the transmission and a decrease in the speed of movement due to an increase in the bypass of the working fluid through the valve from the discharge to the suction cavity of the corresponding hydraulic machine. The torque of the “running-in” wheel during rotation decreases with synchronous rotation of the wheels due to the longer trajectory of its movement compared to the “lagging” wheel, and even with a small turning radius can even change its direction. In this case, limiting the torque of this wheel with the bypass valve does not make sense. With reduced grip of the “lagging” wheel, the limitation of its torque with the bypass valve creates the risk of oversteer and loss of lateral stability of movement, due to a change in the sign of the moment to the resistance to rotation. So the advisability of limiting the torques of less loaded wheels with the help of electrically operated bypass valves in the synchronous rotation mode of the wheels is doubtful.

Thus, using this device, it is possible to provide only two modes of operation of the drive wheels: differential and blocked. The lack of partial self-locking mode cross-axle differential communication | 1 |, | 2 | does not allow the use of this device in off-road conditions with unequal grip coefficients. Although this drawback of the device could be eliminated if a corresponding high-pressure regulated throttle was included in its high-pressure line, it still has a number of significant drawbacks that impede its practical implementation.

The circulation of the working fluid between the rotating stators of the hydraulic machines is carried out through the fixed sliding bearings in the presence of radial gaps. Given the complexity of their reliable sealing at high working pressure in the system, this will lead to increased leakage of the working fluid. For example, in hydraulic systems of automatic transmissions in the presence of the same hydraulic communications with appropriate seals and a similar type of hydraulic pumps, the relative proportion of leakage of the working fluid is 30 ... 40%, despite the low working pressure of 1-1.2 MPa.

Transmission through hydraulic machines to the driving wheels of full torque with limited dimensions of the main transmission housing, requiring a compact design of hydraulic machines, is associated with the need to increase the working pressure. If we take into account increased traction loads in off-road driving conditions, then the working pressure in hydraulic machines can increase to the maximum (for the gerotor type) level of 16 ... 18 MPa. With this level of operating pressure, the possibility of reducing the total volumetric loss in hydraulic transmission relative to the above level is unlikely. This means a significant reduction in efficiency. drive the drive axle of the wheels when using the considered device.

In addition, due to the limited dimensions of the structure, it is impossible to provide the necessary 1.2-1.5 m / s flow rate of the working fluid in the suction line, and at a higher flow rate, the normal operation of the hydraulic transmission is disrupted due to air entering the working cavities of the hydraulic machines. For its reliable operation, a closed circuit of the working fluid circulation with feeding the suction line from a special hydraulic pump (make-up) is necessary. At the volume loss level indicated above, the required performance of this pump will be overestimated, which will require additional energy and fuel consumption.

Therefore, the proposed | 2 | the layout of the hydraulic differential with the placement of hydraulic machines loaded with full wheel torques, in one unit with the driven gear of the main gear, repeating the layout of the gear MKD, is not effective due to the increased volumetric losses in hydraulic communications of hydraulic transmission, lowering the efficiency of the drive wheels, as well as due to overall restrictions on the size of the working volume of hydraulic machines and the torques transmitted by them.

The basis of the present invention is an alternative MCD scheme, consisting of two single-row totalizing planetary gears located in wheel reduction gears in which one pair of the corresponding input links has a rigid kinematic connection with the driven gear of the main gear, and the other pair is connected by a hydrostatic transmission with two reversible-action hydraulic machines, the stators of which are fixed motionless.

The objectives of the present invention is to provide a transmission with hydraulic interaxle and interwheel differential couplings for ATC (4k4) cross-country ability, providing at least two modes of self-locking of the wheels of the driving axles with the dependence of the locking moment on the square of the difference in the frequency of rotation of the wheels and the modes of full locking and unlocking with an automatic system control the selection of the best mode for them in terms of maneuverability, cross-country ability, the level of energy loss for slipping and in the automatic transmission system; as well as reducing the dynamic loading of the power train and ensuring the necessary maneuverability and the ability to start the engine when towing the vehicle.

The technical result is an improvement in the functional characteristics of the ATS (4k4): maneuverability, maneuverability, efficiency, reliability.

The solution to these problems is achieved by the inclusion in the transmission of an all-wheel drive automatic telephone exchange, containing a transfer case with front and rear outputs, portal-type drive axles with misaligned wheel gears and final drives, hard kinematic coupling of the driven gears of the latter with the corresponding left and right half-axles and with input cylindrical pairs of wheel gears the driven gears of which are connected with the ring gears of single-row summing planetary mechanisms installed at the output of the wheel ed Ktorov and cross-axle differential providing communication via the sun gears and unregulated hydrostatic transmission comprising a reversible hydraulic machine steps, such radial-plunger type, the housing fixed to the body the corresponding gear wheel; the suction working cavities of the hydraulic machines of each drive axle in traction mode through the reverse spools are interconnected by a low-pressure line, which includes an automatic hydraulic control unit for blocking the cross-axle differential connection (MKDS) at negative torques of the ATS wheels, which contains two hydraulically-controlled spools of постоянно constantly open ’and ″ Permanently closed ″, and equipped with a make-up system, and the injection cavities of the hydraulic machines in the traction mode of the wheels are connected to the end inlet cavities of a hydraulically controlled three-position selective valve with centering springs and positive overlap in the neutral position of the outlet cavity, which is always connected to the discharge line of a more loaded hydraulic machine with the hydraulic damper connected to it, and also connected to the inputs of the electro-hydraulic control unit for blocking the cross-axle differential communication (MKDS) in traction mode of the drive axle, including a blocking hydraulic mechanism with an electrically controlled speed this change in hydraulic resistance, connected in series with an electrically controlled locking spool, which are the executive mechanisms of the automatic control system (ACS) of the MKDS locking modes when the ATS is rotated, duplicated by the manual control button to turn on the complete transmission lock and automatically enable either one of the two self-locking modes, main or additional with different hydraulic resistance of the blocking throttle, or the full blocking mode according to the commands of the electronic control unit with corresponding deviations of the current values of the difference of torques and angles of rotation of the front wheels from the specified threshold values, and the current values of the difference of the frequency of rotation of the front wheels from the calculated upper or lower threshold values based on the measurement of the wheel speed, the steering angles of the front wheels wheels and pressure in the injection cavities of the hydraulic machines of these wheels; in this case, the front and rear outputs of the transfer case mentioned above are rigidly interconnected, and the interaxial differential connection (MODS) of the driving axles is provided by parallel connection of the outputs of the automatic hydraulic control units of the locking axles of the axles of the main axles mentioned above with the common axle trunk low when the drive axles are traction pressure and output lines of selective valves - with a common center line of high pressure traction axles in the traction mode, irrespective of the number of driving axles in the transmission, the output line of the rear axle selective valve is connected directly to the common axle line, and for the rest of the front axles located in front, they are connected via electrically operated manual push-button hydraulic dual-mode locking mechanisms for controlling the mode of differential interaxial differential communication (MODS), which provide either self-locking mode due to the hydraulic resistance of the locking mechanism in the traction mode of the drive axles, or lnoy locks operated simultaneously with the complete blockage of MKDS for all drive axles.

In FIG. 1 is a kinematic and hydraulic transmission diagram; FIG. 2, 3, 4 and 5 non-axial wheel gearbox with integrated radial plunger hydraulic machine of constant working volume, in FIG. 6 is a hydraulic diagram of a hydraulic unit of a front driving axle, in FIG. 7 is a hydraulic diagram of a rear axle hydraulic system block; FIG. 8 is a diagram of the interaxle and interwheel hydraulic connections between the discharge lines of the hydraulic machines of the driving bridges, FIG. 9 - throttle hydraulic locking mechanism MODS, in FIG. 10 is a block diagram of a system for automatically controlling the modes of cross-axle differential communications when turning the ATC; in FIG. 11 is a functional diagram of an electronic computing unit; FIG. 12 is a functional diagram of converting analog signals to digital and generating control commands in an electronic control unit, FIG. 13 is a circuit diagram of an automatic control of actuators and signaling.

The transmission (Fig. 1) contains a gear change box - 1, a two-stage transfer case - 2 with a front - 3 and a rear output - 4, front axles - 5 and rear - 6 with driven gears - 7 and 8 of the main gears, rigidly connected with semi-axes - 9, 10, 11 and 12, misaligned wheel gears - 13, 14, 15 and 16 and hydraulic machines - 17, 18, 19 and 20 of the radial-plunger type. Wheel reducers consist of two parts: internal and external. The internal stationary part of the wheel gears (Fig. 2, 3) (without suspension elements) contains a housing - 21, made integral with the hub - 22, and a cover - 23. In this part of the wheel gears there is an input cylindrical pair of gears: drive - 24 at the input the shaft - 25, connected by a cardan joint to the corresponding axis of the drive axle, and the driven - 26, which is rigidly connected to the end of the tubular driven shaft - 27, mounted on bearings inside the fixed hub - 22. On the inner spline shaft of the driven shaft - 27 is fixed chataya coupling half - 28 with involute profile of external teeth, the number and size of which is the same as that of the ring gear - the planetary gear 29 and the coupling half which mates with the internal toothing of the latter. In this case, in the axial direction, the ring gear - 29 is fixed by a split retaining ring - 30. On the outer surface of the hub - 22 on the angular contact bearings - 31 there is a rotating hub - 32 wheels. The axial clearance of the bearings - 31 is adjusted by the locking nut - 33. The brake disc - 34 is fixed on the hub - 32. The housing - 36 of the movable part of the wheel gear and the outer part - 37 of the carrier of the planetary gear are docked to the end face of the hub - 32 with the help of studs - 35, which at the same time acts as a housing cover - 36. A wheel disk - 38 is attached to the outer crown of the housing - 36. The outer part - 37 of the carrier is rigidly connected to its inner part - 39. In the cylindrical bores of the latter on the axes - 40 and bearings are installed There are three satellites - 41. Inside the tubular shaft - 27 there is a shaft - 42, made at the same time with the sun gear - 43. The outer shaft end - 42 is mounted on the bearing - 44 in the through cylindrical bore of the outer part - 37 of the carrier, and the inner spline shaft with with the help of a leading gear half-coupling - 45 is connected by a driven gear half-coupling - 46, attached to a rotating rotor - 47 of a radial-plunger hydraulic machine. In the rotor - 47 in the radial bores there are seven (in this version) spring-loaded plungers - 48 (Fig. 3), which with their outer ends abut the axially movable axes - 49 support rollers - 50, in contact with the guides - 51 of the fixed stator - 52 In the rotor - 47 (Fig. 3, 4, 5), a sleeve - 53 with holes - 54 is pressed in for inlet and outlet of the working fluid. The rotor - 47 together with the sleeve - 53 rotates on a stationary distribution journal, consisting of a housing - 55 axles, equipped with two outer ring grooves - 56, axial - 57 and radial - 58 channels for supplying and discharging the working fluid, and a bronze sleeve - 59 s radial channels - 60. In this case, sleeve - 59, along with the function of distributing the working fluid, acts as a sliding bearing for the rotating rotor - 47. Axial channels - 57 are connected with threaded holes - 61 and 62 from the outside of the housing - 55 trunnions for fittings (in FIG. . 2 and 3 not according cauldrons) of connecting lines between hydraulic machines and the hydraulic unit of the corresponding drive axle. There, a threaded hole - 63 was made for connection with a drain line to divert external leaks of the working fluid from the internal cavity of the stator - 64.

Unlike the known device | 5 |, the torque on the shaft of the hydraulic machine is (k + 1) times less than the torque on the wheel (k is the characteristic of the planetary gear set).

This, as well as the radial-plunger type of a hydraulic machine with a maximum pressure drop of 30 MPa, ceteris paribus, can reduce the working volume of hydraulic machines used by almost an order of magnitude in comparison with the known device.

Through pipelines - 65, 66, 67, 68 hydraulic machines - 17, 19 of the front drive axle are connected to the corresponding input lines - 69, 70, 71, 72 of the hydraulic system block - 73 of the front drive axle - 5, and through pipelines - 74, 75, 76 , 77 hydraulic machines - 18, 20 of the rear driving axle are connected to the corresponding input highways - 78, 79, 80, 81 of the hydraulic system block - 82 of the rear driving axle - 6.

To make up for external leaks of the working fluid in hydraulic machines and to maintain a small (rp = 0.4-0.5 MPa) overpressure in their suction cavities, the transmission is equipped with a recharge system. This system contains two gear hydraulic pumps - 83 and 84. The main hydraulic pump - 83, is driven by the primary engine, for example, V-belt drive - 85, the additional hydraulic pump - 84 is driven by the driven shaft - 86 of the transfer case, which has a constant kinematic connection with the drive wheels of the ATS. The hydraulic pump - 84 provides recharge of hydraulic machines when towing a telephone exchange and an idle engine. After starting the engine, the main hydraulic pump - 83 is connected to the make-up. The pressure in its discharge line - 87 is limited by the bypass valve - 88. In the discharge line - 89 hydraulic pumps - 84 when the ATS moves, the pressure is limited by the bypass valve - 90, which is adjusted to the same pressure as and a valve - 88. An unloading valve - 91 with hydraulic control is also connected to this line. The working fluid is supplied to its control cavity through the line - 92 controls from the discharge line - 87 hydraulic pumps - 83. The valve - 91 is adjusted to a pressure slightly lower (PN = 0.3-0.4 MPa), in comparison with the valves - 88 and 90. When activated the discharge valve - 91, the discharge line - 89 of the hydraulic pump - 84, is connected to a free drain (into the reservoir for the working fluid). The common make-up line - 93 front hydraulic machines and rear hydraulic machines is connected to the discharge lines - 87 and 89 of the aforementioned hydraulic pumps with the help of inlet check valves - 94.

The inlet lines of the hydraulic system units - 73 and 82 (Fig. 6, 7) of the front and rear driving axles using the intake check valves - 95 are connected to the supply line - 93 if the pressure in them is lower than the above charge pressure level, and using the exhaust check valves - 96 are connected to the corresponding safety valves - 97 for transferring the working fluid to the make-up line - 93, if their pressure exceeds a predetermined upper level (30-32 MPa).

The input lines - 69, 70, 71, 72 of the hydraulic system block - 73 of the front drive axle are connected to the inputs of the corresponding electrically operated on-off four-way spools - 98, 99 of reverse, and the input lines - 78, 79, 80, 81 of the hydraulic system block - 82 of the rear drive axle with inputs of similar spools - 100, 101. The reverse spools are switched on automatically, either by the signal of the reverse gear switch or by the signal of the brake pedal position sensor.

Blocks of hydraulic systems - 73 and 82 contain a block - 102 of electro-hydraulic control of the locking modes of MKDS in the traction mode of the drive axle when turning the ATS. It is identical for front and rear drive axle hydraulic systems. Block - 102 has a right (according to the scheme taking into account the direction of movement) - 103 and left - 104 input channels that are connected to the output lines - 105, 106 of the corresponding spools - 98, 99 of reverse with high (in the traction mode of the drive axle) pressure. By means of two exhaust valves - 107, either the right inlet channel - 103 or the left - 104 is connected to the input - 108 of the hydraulic blocking mechanism - 109. The output - 110 of the hydraulic blocking mechanism using the inlet check valves - 111 is connected either to the right - 103 or to the left - 104 the input channel of the block - 102. The hydraulic locking mechanism - 109 contains sequentially connected electrically controlled solenoid C31 two-position two-way spool - 112 full blocking, throttle - 113 with a low coefficient of resistance and drop Fir - 114 with a large resistance of 4-5 coefficient. Block - 102 is equipped with an electrically controlled two-position two-way spool - 115, which, when turned on by a C41 solenoid, connects the output 116 from the first throttle to the output - 110 of the hydraulic mechanism, disconnecting the throttle - 114, and a hydraulically controlled two-position two-way spool - 117, the end control cavity of which is connected to the main control - 118, and which, when turned on, connects the input - 108 to the output - 110 of the hydraulic locking mechanism - 109. This ensures a direct connection of the right - 103 and left - 104 input channels in block - 102 bypassing hydraulic locking mechanism - 109.

Blocks of hydraulic systems - 73 and 82 contain a block - 119 of automatic hydraulic control of the locking modes of MKDS with negative torques of the wheels of the drive axle. It is identical for front and rear drive axle hydraulic systems. Block - 119 has a right - 120 and left - 121 input channels, which are connected to the output lines - 122, 123 of the corresponding spools - 98, 99 reverse with low (in the traction mode of the drive axle) pressure. These channels are connected in parallel with the corresponding input channels of the hydraulically controlled two-position three-way spools, “constantly open” - 124 and “constantly closed” - 125. The end control cavity of the spool - 125 is connected to the main line - 92 controls (83 feeds from the pump), and the end control the spool cavity - 124 is connected to the aforementioned control line - 118, which is connected via inlet check valves - 126 either to the right - 120, or to the left - 121 input channel of the block - 119. At the same time, the return spring Spools - 124 adjusted to 0.1-0.15 pressure from the maximum working pressure, Limited bypass valves - 97. The desired adjustment of the spring corresponds to a negative torque during the idling wheel rotation transmission parts and the crank shaft of the engine to start it towing PBX.

The hydraulic units - 73 and 82 of the front and rear drive axles contain hydraulically controlled three-position selective valves - 127. Each valve is equipped with two centering springs. Inlet end cavities “a” and “b” of valves - 127 are connected to highways - 105 and 106 of high (in the traction mode of the wheels) pressure. The output cavities - 128 valves are connected by the output lines - 129, 130 in the hydraulic systems of the front and rear axles, respectively, through throttles - 131 with hydraulic accumulators - 132 with the purpose of damping the peak pressure spikes and with the pressure switch - 133 to signal the upper preset pressure level. Valves - 127 in the neutral position have a positive overlap of the outlet cavities - 128 relative to the inlet cavities - “a” and “b”.

The outputs of the check valves - 96 in the hydraulic unit - 73 of the front drive axle in parallel with the aforementioned safety valves - 97 are connected to pressure sensors - 134, which are used to determine the difference in torque between the front wheels (in full lock mode).

If the pressure of the working fluid in the cavities “a” and “b” is equal and the central position of the valve is 127, the outlet (and the inlet) of the working fluid from the cavity - 129 is closed, and if it is not equal, the valve - 127 is shifted to one of two extreme positions, connecting the outlet cavity - 128 valves with its end cavity (“a” or “b”), in which the pressure is higher and which is connected with the injection cavity of a more loaded hydraulic machine of the drive axle, operating in this case in pump mode.

The output lines - 129 and 130 of the selective valves - 127 (Figs. 1, 8) for a biaxial automatic telephone exchange form an axle line of high (in the traction mode of the drive axle) pressure. Between these highways (Fig. 1) an electrically controlled hydraulic locking mechanism is included - 135 for controlling the locking modes of interaxial differential communication (MODS). As follows from Fig. 8, with a three-axle running system, the high-pressure center axle line also consists of line 130 and two lines connected in parallel with it — 129 with hydraulic locking mechanisms — 135 of the front and middle drive axles. And with a four-axle running system with a highway - 130, three highways - 129 with 135 hydraulic locking mechanisms will already be connected in parallel.

The output lines 136 (FIGS. 6, 7) associated with the spool outputs 124 and 125, the blocks 119 for hydraulic control of the MKDS blocking at negative wheel torques are connected in parallel with the center line 137 of low (in the traction mode of the driving axles) pressure.

The hydraulic locking mechanism 135 of the MODS blocking control mode (FIG. 1) contains a choke 138 connected in series and electrically controlled from the manual control button K _u2 (FIG. 13), a two-position spool valve — 139 full MODS blocking. The spool is turned on - 139 with the K _u2 button at the same time as the spools are turned on - 112 full blocking of the MCD. When the spool -139 is turned off, a self-locking mode takes place with a higher stiffness of characteristic (1) than with MKDS self-locking. In this regard, the throttle 138 (Fig. 9) has a 1.5-2.5 times higher hydraulic resistance in comparison with the throttle 114. Both of these throttles, in order to stabilize the resistance coefficient during fluctuations in temperature and viscosity of the working fluid, are plate-like, in which the working the liquid is passed sequentially through washers - 140, installed with a small gap, and equipped with through throttle holes “with” 1.5-2 mm in diameter and 1.5 mm in length. Chokes - 114 and 138 differ only in the number of washers - 140.

The automatic control system (ACS) for locking the cross-axle differential connections when turning the ATC in the traction mode of the driving axles (Fig. 10) includes the aforementioned sensors - 134 pressures in the injection cavities of the front drive axle hydraulic motors, sensors - 141, 142 of the rear and front wheels, sensors - 143 steering angles of the front wheels. The signals of these sensors for the left and right wheels r _l , r _p , ω _2p , ω _1l , ω _1p θ _l and θ _p , in the form of analog signals are input to the electronic computing unit - 144. On its functional diagram (Fig.11) mathematical formulas are presented that calculate the current values of the calculated value θ of the angle of rotation of the wheels and its absolute value | θ |, the actual Δω _zo and theoretical Δω _theor (excluding slipping and lateral wheel drive) for a given value | θ | difference in the rotational speed of the front "runs" and "lagging" of the wheels, the difference in torque ΔM _Lake Front "lagging" and "runs" of the wheels, the absolute value of a predetermined theoretical (disregarding slippage) translational velocity | V ₀ |, and a threshold upper Δω _max and lower (negative value) Δω _min values of the difference in the rotational speed of the front “running” and “lagging” wheels. In these formulas, the design parameters of the ATS: r _k1 and r _k2 are the rolling radii of the front and rear wheels, θ _max is the maximum design value of the calculated value of the angle of rotation of the front wheels. The calculated value θ of the angle of rotation of the front wheels is equal to the angle of rotation of the conditional (equivalent) front wheel with a vertical axis of rotation at the intersection with the longitudinal axis of the vehicle, at which the position of the instantaneous center of rotation of the vehicle is maintained. To determine Δω _{max, we} used the correction coefficient K, which is equal to the ratio of the upper threshold value Δω _max and theoretical Δω _{theor of the} values of the difference in the rotational speed of the front “running” and “lagging” wheels, defined as a function of two variables | V ₀ | and | θ |. To calculate it, the constants K _v , A ₀ ... A _{4 are given} , which are approximation coefficients of the dependence of the averaged actual values of the correction coefficient K on | V ₀ | and | θ | obtained by computer simulation of the circular motion of the ATS on the ground with various combinations of friction coefficients and rolling resistance of “running” and “lagging” wheels with the limiting slipping of the most loaded one of the two “running” wheels moving in worse conditions compared to "Lagging behind." To determine Δω _min , the minimum permissible relative value ξ _Δω0 specified in the form of a linear function of | θ |, where ξ ₀ and k _θ are approximation coefficients obtained in a similar way, but under identical or worse traffic conditions of “lagging wheels” in comparison “Running-ahead” for those modes when Δω _zo <0. In order to identify a “running-in” and “lagging” front wheel when turning the ATS, the values of θ _p and θ _{l of the} angles of rotation of the front wheels are taken to be positive values for a right turn, negative values for a left turn, and to an electronic computing unit (Fig. 11) a relay link is included - 145 with a deadband Δθ, into which the current value of the calculated value of the angle of rotation θ of the front wheels is entered. The output signal of this link S _θ at zero angles | θ | <Δθ is equal to zero, in this case, the automatic control system for the blocking modes does not work, and for large values | θ | depending on the sign of θ, it is either -1 for a right turn, or +1 for a left turn. With S _θ = -1, the left front wheel is “running”, and with S _θ = + 1 - “lagging”. The range -Δθ <θ <Δθ approximately corresponds to the traffic conditions of the ATS on paved roads when the turning radii do not decrease less than 120-150 m.

The above parameters, calculated in block 144, enter the electronic control block 146 (Fig. 12). Block 146 also introduces fixed threshold values θ ₁ and θ ₀ (upper and lower) of the calculated value of the angle of rotation of the front wheels and the upper threshold value ΔM _{0 of} the torque difference between the front “lagging” and “running” wheels in full lock mode. In this block, the current values of the parameters Δω _zo , M _oz and | θ | compared with the corresponding threshold values Δω _max and Δω _min , ΔM ₀ , Δθ ₀ and Δθ ₁ . The analog signals Δω, Δω ₀ , ΔM, Δθ ₀ , Δθ ₁ , and also | V ₀ | convert to the corresponding digital signals (1 or 0) S _Δω , S _Δω0 , S _ΔM , S _Δθ0 , S _Δθ1 , S _-Δθ1 and S _V0 with the help of relay links - 147, 148, 149, 150,151,152 and 153. The output signal of the relay links 150, 151 and 153 with a positive analog signal - “1”, and the output signal of the remaining links - “0”. Based on these digital signals, through the logical operations “disjunction” (addition - “v”), “conjunction” (multiplication - “&”) and “inversion” (negation - “not”), one of the two control commands u ₁ or u ₂ . The magnitude of the signals in channels I, II ... VI at the entrance to the “&” link forming the control command u ₁ for various operating modes (A, B, C, D) of the self-propelled guns is given in Table 1 (Fig. 12). Link - 152 is triggered with delay δθ = 0.5 ° -1.0 ° relative to link - 151 with increasing | θ | and with the same lead - with decreasing | θ |. This signal delay S _-Δθ1 = 1 with increasing | θ | and when the threshold value | θ | = θ _{1 is} reached, it guarantees u ₁ = 1 and avoids the failure of the ACS.

The magnitude of the signals in channels VII and VIII at the entrance to the “V” link forming the u ₂ command for various ACS operating modes (D, E, G) are shown in Table 2.

The “1” and “0” turn-off commands for signals u ₁ and u _{2 are} provided subject to the following conditions: u ₁ = 1 - with S _Δθ1 = 1, S _-Δθ1 = 1 and u ₂ = 0; u ₁ = 0 - when S _Δθ0 = 0 or S _Δω = 0 or S _Δω0 = 0; u ₂ = 1 - with S _Δω0 = 1; u ₂ = 0 - at S _ΔM = 0.

After amplification of u ₁ and u _2, signals U ₁ , U ₂ are fed to the corresponding windings of the solenoid control relay in the hydraulic units - 73, 82 of the front and rear drive axles. The command signal U ₁ (Fig. 13) for switching on the additional self-locking mode when turning the ATS is fed to the winding of a constant open relay K _{1 for} controlling parallel-connected solenoids C41, C42 of spools - 115 hydraulic blocking mechanisms - 109 (Figs. 6, 7). Relay K _{1 is} duplicated by the forced activation button K _y1 , and the signal lamp (green) L ₁ signals the inclusion of an additional self-locking mode. In the absence of command signals from the automatic control system for locking the cross-axle differential links (U ₁ = 0 and U ₂ = 0) and the manual control buttons K _u1 and K _{u2 off, the} main self-locking mode is activated. The command signal U _{2 to} turn on the complete blocking of cross-axle differential connections when turning the ATS is fed to the winding of a constantly open relay K _{2 for} controlling parallel-connected solenoids C31, C32 of spools - 112 hydraulic blocking mechanisms - 109 (6, 7). The inclusion of these solenoids is signaled by a signal lamp (yellow) L ₂ .

The signal U _{3 for} switching on the rear input transmission from the sensor - 154 (Fig. 10, 13) is fed to the winding of the constantly open control relay K ₃ (Fig. 13) with solenoids C11, C21, C12, C22 of the spools - 98, 99, 100, connected in parallel 101 (Fig.6, 7). In this case, highways - 105 and 106 are connected to highways - 70, 72 of the hydraulic system of the front axle and highways 79, 81 - of the rear axle. The same solenoids are switched on by a continuously open relay K ₄ when the last signal U ₄ from the sensor - 155 (Fig. 13) is applied to the position of the brake pedal when braking the vehicle. In this case, the unlocking of the cross-wheel differential links is ensured.

The signal U _{5 to} automatically turn on the complete simultaneous locking of the axle and cross-axle differential connections during acceleration of the automatic telephone exchange is supplied from the sensor - 156 (Fig. 13) of the accelerator pedal to the coil of the constantly open relay K ₅ , which controls the inclusion of the solenoids C31, C32 and C50 of the spools - 112 and 139 (figures 1, 6 and 7).

On the traction overload of the most loaded wheel of the ATC is signaled by a signal (red) lamp L ₃ in the circuit of pressure switches in parallel - 133 (6, 7) in hydraulic units - 73, 82 of the front and rear drive axles.

The operation of the transmission in the traction mode of the front and rear driving axles must be considered with two options for indirect motion:

- when the automatic control system of the automatic locking mode is inoperative, when the angles of rotation of the front wheels are small -Δθ <θ <Δθ, and the turning radii of the ATS are at least 120-150 m;

- with a working system of automatic control of the MKDS locking modes at large angles of rotation of the wheels and smaller radii of rotation.

With an idle system of automatic control of the MKDS lock modes and with unused buttons for manual control of the lock modes, the transmission (Fig. 1) in the traction mode of the driving axles works as follows. In the case of equal torques on the driving wheels of each drive axle with the right and left wheels coupling the same, the pressure in the discharge cavities of the respective hydraulic machines and discharge lines - 105 and - 106 of the corresponding hydraulic unit is the same. The flow of working fluid through the spools - 98, 99 of the reverse of the front axle hydraulic system (Fig.6), through the spools - 100 and 101 of the reverse of the hydraulic system of the front axle (Fig.7), the corresponding high-pressure lines 105 and 106 (Fig.6 and 7) and channels - 103 and 104 of hydraulic blocking mechanisms - 109 with equal pressure in the discharge lines - 105 and 106 due to non-return valves - 111 is absent. Selective valves - 127 are in the neutral (central) position, blocking their outlet cavities - 128 and interaxal lines - 129 and 130, blocking the MODS. The rotors - 47 hydraulic machines and sun gears - 43 (figure 2) of the respective wheel gears are stationary. Interconnected by a rigid kinematic connection, the axles - 9, 10, 11, 12 rotate synchronously, ensuring the equality of the rotation frequency of the ring gears - 29 (Fig. 2) and the driving wheels. Blocking MODS at small angles of rotation of the front wheels provides the opportunity to reduce energy loss at large angles of elevation of the roadway.

When the right and left wheels have different adhesion, the wheels of one side of the ATS with a higher coefficient of adhesion are more loaded than the wheels of the other side with a lower coefficient of adhesion. More loaded wheels are slowed down due to the reverse rotation of the sun gears - 43 wheel reducers, and less loaded wheels are accelerated due to the rotation of these gears in the direction of rotation of the wheels. The equality of the pressure of the working fluid in the injection cavities of the respective hydraulic machines and in the lines 105 and 106 (FIGS. 6 and 7), as well as in the input channels 103 and 104 of the blocks 102 of the electro-hydraulic control is violated. The working fluid from the injection cavities of hydraulic machines of decelerating more loaded wheels through the corresponding discharge lines (105 or 106) with a higher pressure and through the intake check valves - 107 will begin to flow to the inlets - 108 hydraulic locking mechanisms - 109 of the front and rear drive axles, and further, if the spools are not turned on - 112 are completely blocked, - to the outlets - 110 and through the check valves - 111 and discharge lines (105 or 106) with less pressure into the discharge cavity of hydraulic machines accelerating less than loaded wheels. When U ₁ = 0 and U ₂ = 0, there is no voltage on the solenoids C41 and C42. The access of the working fluid from the line - 116 to the exit - 110 of the hydraulic locking mechanisms is blocked by the slide valve - 115, therefore, the working fluid passes sequentially through two throttles - 113 and 114, providing the main mode of self-locking MKSD. The pressure drop across the hydraulic blocking mechanism - 109 and the blocking moment are proportional to the square of the flow rate of the working fluid through the blocking mechanism and the square of the difference in wheel speed (1). Under the influence of the pressure difference in the end cavities “a” and “b”, the selective valves - 127 are shifted to the extreme position, towards the end cavity with lower pressure, and their outlet cavities - 128 and the center axle - 129 at the front driving axle and - 130 at the rear drive axle is connected to the discharge cavities of more loaded hydraulic machines. In this case, between the hydraulic machines of more loaded (decelerating) wheels is the interaxle differential connection. When the traction load of the driving axles is not the same, the working fluid is passed through the throttle - 138 (Fig. 1) of the hydraulic blocking mechanism - 135 between the axle lines - 130 and 129 from the pressure-loaded line to the less loaded one. The differential pressure across the throttle - 138 and the blocking moment are proportional to the squared flow rate of the working fluid through the throttle, the magnitude of which depends on the difference in the slipping of the front and rear wheels, will be significant only for off-road traffic with rough terrain and traffic in difficult road conditions at high elevation angles of the road canvases.

In some cases, it is possible to use the complete simultaneous locking of the axle and cross-axle differential connections, which is carried out by turning on the spools 112 and 139 of the hydraulic locking mechanisms 109 and 135 (Figs. 1, 6 and 7) using the K _u2 button (Fig. 13). For example, when moving ATS with large turning radii in difficult road conditions, when the difference in grip and rolling resistance, and, accordingly, the traction load of the right and left wheels varies over a wide range. Fluctuations in the traction load of the wheels and pressure in the mains - 105 and 106 cause the corresponding oscillations of the selective valve - 127, while the accumulator - 132 is always connected to a more pressure-loaded line. Due to this, the stiffness of the drive of more loaded wheels is significantly reduced (3-5 times, depending on the parameters of the accumulator and the average load level). As a result, the peak loads of hydraulic machines and rotating drive elements of more loaded wheels of the front and rear drive axles are “cut off”. The accumulator is a filter of high-frequency components of the traction load. Thanks to the choke - 131, in the process of discharging - charging the accumulator, the amplitude of the forced low-frequency oscillations of the torque decreases. This positively affects both the increase in the transmission resource and the decrease in slipping of more loaded wheels due to a decrease not only in the amplitude of oscillations, but also in the rate of change of torques.

When turning automatic telephone exchanges with spools turned on - 112, 139 completely blocking the interaxal and interwheel differential couplings (self-propelled axles are turned off), the access of the working fluid from the injection cavities of the hydraulic machines of the “lagging” wheels to the injection cavities of the hydraulic machines of the “running” wheels and from the hydraulic machine of the rear “lagging” wheel to the hydraulic machine the front “lagging” wheel is completely blocked (figures 1, 6, 7). In this case, the pressure in the injection cavities of the “lagging” wheels and their torques increase due to the increase of their slipping, and the pressure drop of the working fluid in the working cavities of the hydraulic machines of the “running-off” wheels and their torques decrease due to the reduction of the slipping. The decrease in pressure in the injection cavities of the hydraulic machines of these wheels is limited by the charge pressure p _p when the working fluid from the line — 93 of the feed through the corresponding inlet check valves — 95 begins to flow into these cavities. In this case, the torques of hydraulic machines operating in the mode of motors, “running” wheels are reduced to zero. Given the mechanical losses in these hydraulic machines and in wheel gearboxes, the wheels will move in “passive” mode with a small negative tangential traction force, which is equivalent to disabling their drive (as when installing mechanisms with overrunning clutches in the wheel hubs to automatically turn off the wheels). If in this case the performance of the main (on the primary engine) hydraulic pump - 83 (Fig. 1) at a given automatic telephone exchange speed is insufficient and the charge pressure decreases below the specified above level p _{at the} setting of the discharge valve - 91, this valve turns off and closes the free draining of the working fluid from the discharge line - 89 additional hydraulic pumps - 84 recharge. The pressure of the working fluid in the discharge lines - 87 and 89 of both hydraulic pumps is equalized and the working line from the two hydraulic pumps - 83 and 84 begins to flow into the make-up line - 93 under pressure p _p = p _y , until the need for the amount of make-up decreases, for example, after completion turning ATS.

Full blocking of the axle and cross-axle differential connections is turned on automatically when the vehicle is accelerated in the event of traffic following a signal u ₅ from the sensor 156 of the accelerator pedal (Fig. 13) through the coil of a constantly open relay K ₅ and voltage supply to the solenoids C41, C42 and C50 of the spools 112 and 139 (figures 1, 6, 7).

When braking the ATS by signal U _{4 of the} sensor - 155 position of the brake pedal using a constantly open relay K ₄ and solenoids C11, C21, C12 and C22 (Fig. 13), the spools - 98, 99, 100 and 101 (6, 7 are turned on) ) reverse, which connect the injection cavity of the hydraulic machines of each drive axle with highways - 120 and 121 directly. At the same time, the pressure in these lines and control line 118 increases, and under its action hydraulic spools 117 turn on, connecting inputs 108 and outputs 110 hydraulic locking mechanisms 109 directly bypassing the throttles 113 and 114, excluding the differential pressure of the working fluid between the cavities of low pressure hydraulic machines. As a result, the cross-axle differential links are unlocked and effective use of the anti-lock braking system (ABS) is ensured.

In some cases of operation of the automatic telephone exchange, driving modes are possible, including non-linear, with negative wheel torques. Such modes include emergency towing of the ATS, starting the engine with the help of towing, coasting during engine braking. In these cases, the working cavities of hydraulic machines and the corresponding input lines of the hydraulic system block - 73 leading bridges change roles. Input lines - 70, 72 and the corresponding lines - 120, 121 (Fig.6, 7), as well as the interaxal line - 137 are connected to the injection cavities of hydraulic machines and the pressure of the working fluid in them is determined by the value of the moment of resistance or idle rotation of the transmission elements from the gearbox to the wheels during emergency towing of the vehicle, or the entire transmission and crankshaft of an idle engine when it is started in tow. Accordingly, in the hydraulic systems of the front and rear driving axles, the working fluid pressure in the main line increases - 118 controls, under the action of which a hydraulically controlled “permanently closed” spool - 117 is turned on, connecting its input - 110 and output - 108 and bypass directly bypassing the hydraulic locking mechanism - 109 and, accordingly, the lines - 105 and 106. The pressure in the end cavities “a” and “b” of the selective valves - 127 is equalized and these valves, occupying a neutral position, block the access of the working fluid to the center axes - 129 and 130 and choke - 138 (Figure 1). The inlet lines - 69, 71 and the corresponding lines - 105, 106 (Fig. 6, 7) of the hydraulic unit - 73 are connected to the suction cavities of the hydraulic machines and through check valves - 95 - with the line - 93 recharge. When the engine is idle, recharge is carried out from an additional hydraulic pump - 84, which is driven from the output shaft - 86 transfer case. In the lines - 105 and 106 of the hydraulic systems of the front and rear drive axles, the same pressure will be set equal to the charge pressure p _{p of the} feed.

In case of emergency towing of automatic telephone exchanges with the gearbox output shaft turned off, the moment of resistance to idle rotation of transmission elements is small. The corresponding pressure of the working fluid in the line - 118 (Fig.6, 7) is not enough to turn on the hydraulically controlled "constantly open" spool - 124, the spring of which is set to a higher pressure, corresponding to the moment of resistance to rotation of the elements of the entire transmission and the crankshaft of the engine when it starts towing a telephone exchange. Therefore, the spool - 124 keeps the off position and interconnects the highways - 120, 121 and 137. This ensures the unlocking of the cross-axle differential connections. At the same time, the difference between the moments of resistance to rotation of the wheels of the ATS and the traction required for its towing is reduced, and its maneuverability is also increased.

When the engine is started by towing the automatic telephone exchange, the hydraulic-controlled spool - 124 under the action of a higher pressure of the working fluid in the line - 118 is turned on, separating its working cavities associated with the lines - 120, 121 and 137. When the engine is idle, from which the main hydraulic pump is powered - 83 recharge line - 92 control pressure p _y = 0. Therefore, the hydraulically controlled “permanently closed” spool - 125 is turned off. When the spool is turned on - 124 and the spool is off - 125 highways - 120, 121 and 137 are disconnected, while the interaxle and interwheel differential are completely blocked. This provides a more efficient crankshaft scrolling and faster engine starting. After the engine starts, the main hydraulic pump - 83 of the charge increases the pressure in the main line - 92 controls to the value p _y and the spool - 124 is turned on, connecting the mains - 120 and 121.

With the working system of automatic control of the differential cross-axle locking modes and with unused buttons for manual control of the locking modes of the transmission (Fig. 1) in the traction mode of the driving axles, it works as follows. When turning the ATS and the unequal length of the trajectory of “running” and “lagging” wheels, the traction load of “running” (external) wheels decreases, and “lagging” (internal) increases due to an increase in the actual peripheral speed of the first and a decrease in the actual peripheral speed of the second and corresponding reducing slipping “running” and increasing slipping “lagging” wheels. There is a difference in the pressure of the working fluid in the injection cavities of more loaded and less loaded hydraulic machines. Due to the reverse rotation of the sun gears - 43 wheel reducers, more loaded wheels slow down their rotation, while less loaded wheels accelerate it due to the rotation of the gears - 43 in the direction of rotation of the wheels. Hydromachines of decelerating “lagging” wheels operate in the mode of hydraulic pumps, and of accelerating “running-in” wheels - in the mode of hydraulic motors. The rear “lagging” wheel has the greatest deceleration, the front accelerating wheel has the greatest acceleration. Accordingly, the first hydraulic machine has the highest productivity, and the last hydraulic machine has the highest flow rate. In this case, the flow of working fluid from the hydraulic machine of the rear “lagging” wheel is divided into two parts. One part of the flow of the working fluid through the corresponding inlet channel (103 or 104) with a higher pressure and through the inlet check valve - 107 (Fig. 7) enters the inlet - 108 of the hydraulic locking mechanism - 109 and then, if the spool is not turned on - 112 full blocking - to the exit - 110 and through the non-return valve - 111 into the inlet channel with lower pressure and through the corresponding discharge line (105 or 106) - into the discharge cavity of the hydraulic machine of the rear “running” less loaded wheel. In this case, the difference in the torques of the “lagging” and “running-in” rear wheels is proportional to the square of the flow rate of the working fluid through the hydraulic locking mechanism — 109 of the rear drive axle. And the other part of the flow of the working fluid through the corresponding discharge line (105 or 106) with a higher pressure and through the selective valve is 127, which, due to the pressure inequality in the end cavities “a” and “b”, is displaced to the extreme side of the end cavity with less pressure, the position enters the center line - 130 high pressure. From this line, the working fluid through the throttle - 138 of the hydraulic locking mechanism - 135 (Fig. 1) and the interaxal line - 129 high pressure enters the inlet cavity - 128 of the selective valve - 127 of the front drive axle (Fig. 6). This valve - 127, like the rear drive axle, is displaced to the extreme position towards the end cavity with less pressure. Due to this, the flow of working fluid from the interaxal line 129 from the hydraulic machine of the rear “lagging” wheel enters the discharge line (105 or 106) with a higher pressure, where it is summed up with the flow of working fluid from the hydraulic machine of the front “lagging” wheel. The total flow of the working fluid through the corresponding inlet channel (103 or 104), inlet check valve - 107, hydraulic blocking mechanism - 109 and inlet check valve - 111 enters the corresponding discharge line (105 or 106) with lower pressure and into the discharge cavity of the front hydraulic machine “Running” wheels. In this case, the difference in the torques of the rear and front “lagging” wheels is proportional to the square of the flow rate of the working fluid through the hydraulic locking mechanism - 135 MODS, and the difference of the torques of the “lagging” and “running” front wheels is proportional to the square of the flow of working fluid through the hydraulic locking mechanism - 109 MKDS front drive axle.

The automatic control system (ACS) operates as follows. With the beginning of the rotation of the ATS at | θ |> Δθ, the control commands U ₁ = 0 and U ₂ = 0 and the spools 112, 115 and 117 of the blocks - 102 of the electro-hydraulic control are turned off and the working fluid is sequentially passed through the throttles - 113 and 114 of hydraulic blocking mechanisms - 109 front and rear drive axles. The main self-locking mode is on. The on state of this locking mode is maintained at small angles of rotation of the front wheels | θ | <θ ₁ (upper threshold value | θ |) and U ₂ = 0 - for Δω _zo > Δω _min , (lower limit value Δω _zo ), where Δω _min <0 (Fig. 12).

Upon reaching | θ | the upper threshold value θ ₁ and for u ₂ = 0, S _V0 = 1 (see mode A, Table 1, Fig. 12) S _Δθ1 = 1 and in channel III the signal is “1”. Under the condition Δω _zo <Δω _max (S _Δω = 1) and in view of S _-Δθ1 = 1 (the link-152 is switched off with a delay δθ = 0.5 ° -1 ° relative to the link 151 with | θ | = θ ₁ + δθ), in channel VI, the signal is also “1”. As a result, u ₁ = 1 and instead of the main mode according to the control command U ₁ = 1 (U ₂ = 0), by means of a constantly open relay K ₁ and solenoids C41 and C42 (Fig. 13), spools - 115 blocks - 102 electro-hydraulic controls ( 6 and 7), which, connecting the inputs - 116 chokes - 114 (with high hydraulic resistance) with the outputs - 110 hydraulic locking mechanisms - 109, turn off these chokes and reduce the hydraulic resistance of the locking mechanisms 5-6 times - 109. Turned on additional self-locking mode with significantly less weight bone above characteristics (1) self-locking allows for large rotation angles of the front wheels to reduce the quantity of blocking moments at the front and rear driving axles, the moment of resistance PBX rotation, lateral withdrawal of the front wheels and torques "lagging" of the wheels. Due to this, the loss of energy on slipping, turning radius decreases and the angular velocity of rotation increases. Due to the lower blocking moments of the MCD, the inclusion of the indicated self-locking mode in the case of approximately equal and reduced grip coefficients of the “lagging” and “running” wheels decreases the specific traction load of the “lagging” wheels, which can improve the ATE cross-country ability in similar off-road driving conditions.

An additional self-locking mode under the condition Δω _max > Δω _zo > Δω _{min is} maintained even when | θ | to the lower threshold value θ ₀ <θ ₁ . In this case, S _Δθ1 = 0 (Fig. 12), but due to S _Δθ0 = 1 and u ₁ = 1 in channels V and III, the signals are “1” (mode B, Table 1) and the control command U ₁ = 1 is saved .

Reverse switch off a main mode and the additional mode latching = U ₁ 0, U ₂ = 0 with the proviso Δω _zo> ω _min occurs in two cases. If the calculated value of the angle | θ | the rotation of the wheels below the threshold value θ ₀ <θ ₁ . In this case, when S _Δθ0 = 0 and S _Δθ1 = 0 in channel III - “0”. This ratio of the upper and lower threshold values excludes the possibility of “looping” the control system in the region of the threshold value [θ | = θ ₁ and stabilizes its operation. In the case of an increase in the difference Δω _{z of} the rotational speed of the “running-in” and “lagging” front wheels, caused by increased slipping of the “running-in” wheels moving under the worst conditions to the upper limit Δω _zo = Δω _max . In various conditions of off-road traffic, this threshold value approximately corresponds to the maximum permissible slipping of the front “running-in” wheel. In this case, at the output of the relay link 151 (Fig. 13) S _Δω = 0 and in channel VI the signal is also “0” (mode B, table 1). At u ₁ = 0, the additional self-locking mode is turned off, and due to the greater stiffness of the self-locking characteristic (1), the difference Δω _{oo of} the rotational speed decreases and at the link output - 151 S _Δω = 1. However, the reverse inclusion of the additional self-locking mode does not occur, since for u ₁ = 0 and S _-Δθ1 = 0 in channel IV, the signal is “0” and, accordingly, in channel VI, the signal is also “0” (mode D, Table 1). In this case, U ₁ = 0, the power supply circuit of the solenoids C41 and C42 opens, the spools 115 (6 and 7) turn off, the hydraulic resistance of the locking mechanisms 109 sharply increases, and the ATC turns with a more stringent self-locking characteristic. The reverse inclusion of the additional mode will occur only after reducing the angle of rotation of the wheels to the upper threshold value θ ₁ ahead of δθ = 0.5 ° -1 °, when S _-Δθ1 = 1 (mode A, table 1) (Fig. 12).

Under certain conditions, with the main or additional self-locking modes, due to the large difference in the slippage of the “lagging” and “running-in” front wheels, the sign of Δω _z may change. This mode of rotation occurs either with the same adhesion coefficients and the rolling resistance coefficients of the “running” and “lagging” wheels and the rotation angles of the front wheels not exceeding 12 ° -15 °, or at any rotation angles and worse driving conditions of the “lagging” wheels, with low coefficient of adhesion, always having a lower weight load in comparison with “running”. In this case, the full blocking of the MCD in comparison with the main and additional modes of self-locking, due to the reduction of slipping, is more economical and provides a higher actual speed. In this case, the absolute value ΔM _oz increases, which, with a negative sign, causes either a decrease in the horizontal moment of resistance to rotation of the ATS or a change in its sign. In both cases, the turning radius is reduced.

When you change the sign of Δω _zo , which occurs simultaneously with the change in the sign of the blocking moment ΔM _{oz of the} front wheels, and decreases Δω _zo to Δω _zo = Δω _min S _Δω0 = 1 (in channel VIII) and regardless of the negative value of ΔM _oz and signal S _ΔM at the output of the link “V” - u ₂ = 1 (Fig.12). In this case, U ₂ = 1, the constantly open relay K2 is turned on, voltage is applied to the winding of the solenoids C31 and C32 and the spools are turned on - 112 full blocking (Figs. 6 and 7). In this case, “over” steering of the ATC is possible, associated with the displacement of the steering pole to the axis of the front wheels and the occurrence of either negative angles of the side drive of the front wheels or the lateral sliding of the rear wheels. Therefore, with the indicated inclusion of the complete blocking of the MKDS, the yellow L ₂ signal lamp is provided. The driver receives a warning signal to reduce the set speed V ₀ .

With an increase in ΔM _oz in channel VII and at the output of the “V” link, the signal “1” is stored until ΔM _oz reaches the threshold value ΔM _oz = ΔM ₀ (S _ΔM = 0) and when Δω _zo > Δω _min (S _Δω0 = 0) at the output of the link “V” u ₂ = 0. When U ₂ = 0 - spools - 112 of full blocking under the action of return springs are turned off, returning to their original (“constantly open”) position. And depending on the given value | θ | either additional or basic self-locking mode is activated.

In off-road non-linear motion in the case of the same but reduced traction of “lagging” and “running” wheels, for example, when driving on dry sand, in order to reduce the traction load and slipping of “lagging” wheels, the weight load of which decreases when turning, it is advisable to replace the main self-locking mode to an additional mode with a softer self-locking characteristic and at small values | θ | <θ _{0 of the} angle of rotation of the front wheels. For this, the relay K1 (Fig.13) self-propelled guns by the MKDS blocking modes is duplicated by the button K _{y1 of} manual forced inclusion (shutdown) of the additional self-locking mode. When this turns on the warning light L ₁ green.

Thus, the proposed transmission with hydraulic interaxle and interwheel differential couplings provided by summing planetary gears in wheel reducers and uncontrolled hydrodynamic gears with non-rotating bodies of hydraulic machines, in comparison with known devices, provides a significant reduction in volumetric energy losses in the hydraulic system and is more suitable for automating locking modes differential bonds. The proposed automatic control system for these modes allows flexible and more rational in comparison with the applied self-locking differentials to distribute torques on the “running” and “lagging” wheels with different ratios of their adhesion coefficients and, due to the reduction of slipping, especially of the “lagging” wheels, increase the passability and the profitability of all-wheel drive vehicles in the conditions of indirect off-road traffic. A stepwise change in the stiffness of the self-locking characteristic allows you to reduce the lateral drag of the front steered wheels and increase the maneuverability of movement. Reducing the stiffness of the power transmission of the more loaded wheels of the front and rear drive axles by incorporating hydropneumatic accumulators with damping chokes in the discharge lines reduces the cyclicity and peak values of the driving load of the drive wheels, which increases the resource and reliability of the transmission and expands the possibility of using differential locks in difficult driving conditions connections. The proposed dual-pump recharge system for the suction cavities of hydraulic machines and low-pressure lines makes it possible without automatic couplings in the wheel hubs with full blocking and small turning radii of the automatic telephone exchange to automatically turn off the drive of “running” wheels to increase operating efficiency. Replacing gear differentials (bevel sprockets and cylindrical axle differentials) in a four-wheel drive ATE transmission with single-row planetary mechanisms placed in wheel non-axial gearboxes of portal drive axles significantly reduces the range of used parts and simplifies the design of the transfer case at 4k4 (or transfer case at 6k6, 8k6, 8k6, 8k6, )

Information sources

1. Andreev A.F. and other Differentials of wheeled vehicles. M., publishing house "Engineering", 1987 (p. 50, 85-86).

2. Lowell J. Differential speed-sensitive and torque-sensitive limited slip coupling. US Patent 5,938,556, F16H 48/26, 08/17/1999.

3. Schrand E. Limited slip differential with integrated solenoid valve and plenum. US Patent 6,902,506 B2, F16H 48/20, June 7, 2005.

4. Narbutovsky I.G. Differential controlled radial piston. RU Patent 2238460 C2, F16H 48/26, 04.02.2003.

5. Duan X. Differential device. US Patent 6,544,13682, F16H 48/30, 04/08/2003.

Claims (11)

1. Transmission with hydraulic interaxal and cross-axle differential connections with automatically controlled locking modes for off-road vehicles (ATS), designed primarily for off-road traffic, including a gearbox with a reverse gear sensor, a two-stage transfer case with front and rear output, and portal gantry bridges type with main gears, half shafts and wheel misaligned gearboxes with input cylindrical pairs, the drive gears of which are single with half shafts and kinematically connected with the driven gear of the main gear of the corresponding drive axle, and the output single-row planetary gears, the carriers of which are connected with the hubs of the drive wheels, with volumetric reversible unregulated hydraulic machines built-in as power transmission links between the driven gears of the main gears and the drive wheels, and injection cavities which are interconnected by respective connecting lines equipped with electrically controlled spools b the windows of the injection cavities of hydraulic machines, two-position electrically controlled from the reverse gear switch by reverse spools, bypass valves and blocking throttles, as well as with steering wheel rotation sensors, wheel speed sensors, brake pedal position and accelerator pedal sensors, an electronic control unit, characterized in that in order to increase the maneuverability, maneuverability and efficiency of automatic telephone exchanges, reduce dynamic load power train in conditions off-road traffic, ensuring the necessary maneuverability and the ability to start the engine when towing the ATS, the axles of each drive axle are rigidly interconnected with the driven gear of the main gear, the driven gears of the input cylindrical pairs of wheel gears with the ring gears of the planetary mechanisms mentioned, and the sun gears of the latter with the shafts of hydraulic machines, for example radial plunger, while the housing of the latter is rigidly fixed to the housing of the corresponding wheel gears, and the suction working The axle of the hydraulic machines of each drive axle in traction mode through the reverse spools mentioned above are interconnected by a low-pressure line, which includes an automatic hydraulic control unit for blocking the cross-axle differential coupling (MKDS) at negative torques of the wheels of the automatic telephone exchange, containing two hydraulically controlled spools of постоянно constantly open ’and ″ Permanently closed ″, and equipped with a recharge system, and the injection cavities of the hydraulic machines are connected in the traction mode of the wheels with the inputs of the electrohydraulic unit automatic control of the cross-axle differential communication (MKDS) locking modes, including a hydraulically controlled unlock spool, a hydraulic locking mechanism with an electrically-controlled stepwise change in hydraulic resistance and an electrically-controlled full-lock spool, which are actuators of the automatic control system (ACS) of the MKDS locking modes when turning the automatic telephone exchange, duplicated by a manual button full transmission lock control, and ensuring use in the factory the dependence on the rotation angles, the difference in the rotational speed and the torques of the front steered wheels or one of two self-locking modes, the main one with high hydraulic resistance of the blocking throttle and the additional mode - with low hydraulic resistance or full blockage, as well as with the corresponding input end cavities of the hydraulic three-position and equipped with centering springs selective valve with a positive overlap of the outlet cavity relative to the input and its neutral position, while the output cavities of the selective valves connected to the hydraulic dampers and the low-pressure lines of the hydraulic systems of the drive axles are equipped with the corresponding interaxial hydraulic connections, and the front and rear outputs of the transfer case are rigidly interconnected. 2. The transmission according to claim 1, characterized in that the hydraulic center-to-axle connections of the main axles of the hydraulic systems of the driving axles are provided for the low-pressure manifolds by parallel connection of the outputs of the automatic hydraulic control blocking modes of the MCPC of the main axles of the common axles mentioned in paragraph 1 the inter-axial line of the low pressure traction axles in the traction mode, and for the high-pressure lines, the output cavities of the selective valves mentioned in paragraph 1 with the common interaxle by traction of high pressure axles in the traction mode of the drive axle, and regardless of the number of drive axles in the transmission, the output cavity of the rear axle selective valve is directly connected to the common axle line, and for the others in front of the drive axles, it is connected via electrically operated hydraulic dual-mode locking mechanisms of interaxial differential communication (MODS) ) containing a series-connected choke with high hydraulic resistance and a two-position ″ permanently open ″ electric oupravlyaemy spool, solenoid power control circuit which comprises a permanently open contacts of said claim 1 in the manual transmission full lock control button. 3. The transmission according to claim 1, characterized in that the automatic control system (ACS) for locking the cross-axle differential connections when turning the ATC contains an electronic computing unit, in which, based on measuring the speed of all wheels, rotation angles and pressure of the working fluid in the injection cavities of hydraulic machines of the front steered wheels, a predetermined theoretical speed of movement is calculated, the current values of the difference in the rotational speed of the “running-in” and “lagging” wheels for the front and rear axles are absolute the value of the estimated angle of rotation and the difference in the torques of the “lagging” and “running-in” front steered wheels, the upper one is positive for disabling the additional self-locking mode and the lower one is negative for enabling the full blocking mode, threshold values of the difference in the frequency of rotation of the front steered wheels specified as functions of the current values of the calculated the angle of rotation of the steered wheels and the theoretical speed of movement, and in the electronic control unit of the self-propelled guns equipped with the corresponding relay and logic links, based on a comparison of the current values of the difference in rotational speed, torques and the calculated angle of rotation of the front steered wheels with their corresponding calculated and predetermined threshold values, positive or negative deviations of these parameters are determined in the form of analog signals, which are converted into digital signals, and based on which, with the help of logical operations, control commands are formed: u ₁ for additional mode and u ₂ for complete blocking, which, after amplification, enter the actuators mentioned in Clause 1 in the form of signals U ₁ and U ₂ , and the inclusion and deactivation of the three MCD lock modes specified in Clause 1 is ensured under the following conditions: the main self-locking mode is turned on when U ₂ = 0 and U ₁ = 0 ; disabled when U ₁ = 1 or U ₂ = 1; the additional self-locking mode is enabled at U ₂ = 0 and θ ₁ ≤θ≤θ ₁ + δθ, disabled at θ = θ ₀ or Δω ₃₀ = Δω _max or Δω ₃₀ = Δω _min ; full blocking is enabled at Δω ₃₀ = Δω _min , disabled at ΔМ ₀₃ = ΔМ ₀ . 4. The transmission according to claim 1, characterized in that the make-up system contains two hydraulic pumps, one of which is kinematically connected to the crankshaft of the primary engine of the ATC, and the second to the secondary shaft of the gearbox, the discharge lines of the pumps are connected to the make-up line using exhaust check valves and the pressure in which is limited by individual equally adjusted bypass valves, while the discharge line of the first hydraulic pump is connected to the control line, through which the working fluid they go to the control cavity of the hydraulic unloading valve installed in the discharge line of the second hydraulic pump and connecting the discharge and suction line of the second hydraulic pump, if the control pressure reaches a predetermined level. 5. The transmission according to claim 1, characterized in that in order to reduce the dynamic loading of the transmission, especially in full lock mode, the hydraulic damper mentioned in claim 1 contains a throttle and a pneumatic accumulator connected in series. 6. The transmission according to claim 1 or 4, characterized in that the aforementioned hydraulic block for automatic control of blocking MKDS at negative torques of the wheels of the ATS is equipped with two input channels connected by low pressure traction wheels of the pressure wheels with the corresponding cavities of the right and left hydraulic machines, and the aforementioned in paragraph 1, the hydraulic ″ constantly open ″ and ″ constantly closed ″ spools are spring-loaded and on-off, with two inlet and one outlet cavities, while these cavities are interconnected and with the input channels of the control unit, the end cavity of a “continuously open” spool with a spring adjusted to a pressure of 0.1 ... 0.15 of the maximum value, is connected to the input channels of the control unit through two inlet check valves, and the end cavity is constantly closed ″ Spool - with the control line mentioned in clause 4. 7. The transmission according to claim 1, characterized in that the power circuit of the solenoids of the electrically controlled spools of the reverse of the front and rear driving axles contains a parallel branch with a constantly open relay, in the control winding of which a brake pedal position sensor is included. 8. The transmission according to claim 1 or 3, characterized in that the aforementioned electro-hydraulic control unit for locking the MCD lock modes of each drive axle in the traction mode is equipped with right and left input channels connected to the right and left hydraulic machines for the drive mode of the drive axle, and by two inlet check valves and two exhaust check valves are connected respectively to the inputs and outputs of the hydraulically controlled spool of unlocking referred to in paragraph 1, made by two-position and ″ constant closed with a control end cavity connected to a highway of low pressure for traction drive axle bridge and a hydraulic locking mechanism equipped with a series-connected two-position “permanently open” electrically controlled spool of complete blocking, the power supply circuit of the control solenoid of which contains parallel connected permanently open relay contacts with a control signal U ₂ and the manual control button mentioned in paragraph 1, and a blocking inductor, consisting of of two sections with unequal hydraulic resistance: a permanently switched on section with a low hydraulic resistance and a section with a high hydraulic resistance, which can be switched off by a two-position, “permanently closed”, electrically controlled by a constantly open relay and a signal U _{1 of the} spool connecting the input and output of the section in the off position blocking throttle with high hydraulic resistance. 9. The transmission according to claim 3, characterized in that for turning on the self-propelled guns and determining ″ running-in ’and ающих lagging’ wheels when turning the ATC, the electronic computing unit is equipped with a relay link with a deadband Δθ corresponding to the range of variation of θ when driving with turning radii of at least 120 ... 150 m, the input of which receives the current value θ calculated in this block of the calculated value of the angle of rotation of the front wheels, while in the case | θ | <Δθ - S _θ = 0 and the self-propelled gun is off, with | θ | ≥Δθ - S _θ = 1 and the left wheels are ″ lagging ″, and with | θ | ≤-Δθ - S _θ = -1 and the left wheels and - ″ running ″. 10. The transmission according to claim 3, characterized in that to ensure the specified condition θ ₁ ≤θ≤θ ₁ + δθ enable additional self-locking mode, the electronic control unit is equipped with two relay links with a common analog input signal Δθ ₁ deviation of the angle of rotation of the steered wheels from the top threshold value and with digital output signals: S _Δθ1 and its inverse - S _-Δθ1 , the latter having a delay δθ = 0.5 ... 1.0 ° relative to the signal S _Δθ1 . 11. The transmission of claim 8, characterized in that the resistance coefficient of the permanently turned on section of the blocking inductor, which provides an additional self-locking mode of MKDS with a “flat” characteristic, is 5 ... 6 times less than the total resistance coefficient of the constantly on and off sections of the blocking inductor, which provide the main mode self-locking MKDS with ″ cool ″ characteristic.

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