SU1581614A1 - Mechanism for smooth engagement of gears of vehicle hydromechanical transmission - Google Patents

Abstract

The invention relates to vehicles and can be used in hydromechanical transmissions, mainly for vehicles of high unit power and payload. The purpose of the invention is to increase efficiency by increasing safety in operation. The drain-type soft start mechanism consists of identical pressure regulators 16 to 18, the inputs of which are connected to hydraulic cylinders 2 to 4 of transmission 1, the end measurement measurement chambers communicate with the inputs through throttles 24-26 and check valves 27,28,29, as well as the pressure cavity of the battery 19. The outputs of the pressure regulators are connected to the drainage line 20, and the latter via a non-return valve 32 to the output of the device 11 for automatically unlocking the torque converter. In the event of failure of any pressure regulator associated with jamming of its shutter in the open position, the time during which the dangerously low pressure level is maintained in the corresponding transmission hydraulic cylinder is limited to the specified period, after which it is forcibly increased by means of the device 11 to its nominal value. This virtually eliminates the possibility of damage to the friction of the transmission 1 in the event of malfunction of the soft off mechanism. 1 il.

Description

t

(21) 4398767 / 31-11

(22) 03/28/88

(46) 07/30/90. G. Jul. B 28

(71) Institute of the problems of reliability and durability of machines of the Academy of Sciences BSGR

(72) L.G.Krasnovgky

(53) 629.113 (088.8)

(56) Copyright certificate) USSR t, 1008022, cl. R 60 K 20/14, 1985.

(54) MECHANISM OF SMOOTH MECHANICAL TRANSPORT SHROMECHANICAL TRAP-MSSII VEHICLE

(57) The invention relates to vehicle technology and can be used in hydromechanical transmissions, mainly for vehicles with a large single unit.

power and load capacity. The purpose of the invention is to increase efficiency by increasing safety in operation. The drain-type soft start mechanism consists of the same pressure regulators 16–18, the inputs of which are connected to the hydraulic cylinders 2–4 of the transmission 1, the end-adjustment chambers of adjustment are communicated with the inputs through the throttles 24–26 and check valves 27–29, as well as from . 19). The outputs of the pressure regulators are connected to the steve gi / foline 20, and the latter via a non-return valve 32 to the output of the device 11 automatic unlocking of the torque converter. In the event of failure of any pressure regulator associated with seizure of its

(L

21 27

22 28

Jj

2329

15

31

ate

00

five

Hm

the shutter in the open position, the time during which a dangerously low level of pressure is maintained in the corresponding hydraulic cylinder of the transmission is limited to a specified period after which it will forcibly increase

The invention relates to a transport technique and can be used in hydromechanical transmissions, mainly for vehicles of high unit power and payload.

The purpose of the invention is to increase efficiency by increasing safety in operation.

The drawing shows a schematic diagram of the mechanism for the smooth engagement of hydromechanical transmission gears.

Hydromechanical transmission 1

(depicted in a simplified way), consists of a multi-stage gearbox with several (for example, three) multi-plate clutches for switching gears through hydraulic cylinders 2-4, working alternately, and a torque converter with a friction lock engaged by the hydraulic cylinder 5.

The hydraulic system 6 of the transmission contains a hydraulic station and control devices that are connected by hydraulic lines 7–9 to hydraulic cylinders 2–4. Arrow 10 shows the driver’s effect on the control device. The hydraulic lines 7-9 are also connected to the inputs of the device 11 for automatically unlocking the torque converter of known design, output 12 of which is connected to the input of the actuating valve 13 of the torque converter lock. The output of the valve 13 is in communication with the hydraulic cylinder 5. The valve 13 is controlled by devices included in the hydraulic system 6, on the hydroline 14

Smooth switching mechanism 15. The drain type consists of identical regulators 16–18 of pressure of known construction according to the number of hydraulic cylinders of the gearbox, piston hydraulic accumulator of torus 19. The inputs of regulators 16–18 are connected to hydraulic lines 7–9 parallel to the hydraulic cylinders 2–4 and the outlets to the drain Hydrolines 20. Face cameras change settings

using device 11 to the nominal value. This virtually eliminates the possibility of damage to the friction of the transmission 1 in the event of malfunction of the soft off mechanism. 1 il.

five

0

five

0

5 0 5

0

five

regulators hydrolines 21-23 communicate with the pressure cavity of the hydroaccumulator 19. The same cavity through the inductors 24-26 for charging the hydroaccumulator and separation valves 27-29 of the device, made in the form of check valves, communicated with the hydraulic lines 7-9 and inlets regulators, and through the throttle 30 discharge - with the spring cavity of the hydroaccumulator, which is hydroline 31 communicates with the output 12 of the device 11 unlocking.

The drainage of the hydroline 20 is also connected via a non-return valve 32 to the spring cavity of the hydroaccumulator and via hydraulic line 31 to the outlet 12 of the device 11 ". The return valves 33-35 can be installed between the drainage hydraulic line 20 and the outlets of the regulator. Valves 32-35 are oriented by the inputs towards the regulator outputs.

The device works as follows.

Pa neutral all transmission cylinders 1 off. To activate any transmission of transmission 1, the driver switches on one of the hydraulic cylinders, for example hydraulic cylinder 2, supplying fluid from hydraulic system 6 through hydraulic line 7 into it. Liquid also enters regulator input 16 and through throttle 24 and valve 27 into accumulator 19. Valves 28 and 29 prevent liquid from flowing out in hydrolines 8 and 9. At the same time, unlocking device 11 communicates its outlet 12 and hydraulic line 31 with the drain, which allows the hydraulic accumulator 19 to charge and also turns off the lock cylinder 5, if it was before uh additionally included valve 13.

The activation of the hydraulic cylinder 2 takes place in two stages - filling and pressure buildup.

At the stage of filling, the piston of the hydraulic cylinder 2 moves downwards, choosing

The gaps in the friction disc package (not shown). At this time, due to the large flow of fluid into the hydraulic cylinder and low resistance to movement, the pressure in the hydroline 7 is small, its value is insufficient to open the regulator 16 and charge the accumulator hydroaccumulator.

In the second stage, the piston of the hydraulic cylinder 2 stops, the flow to the hydraulic cylinder 2 stops, the pressure in it and in the hydroline 7 rises and opens the regulator 16. At this moment, the latter is set to low pressure, because the pressure in its end chamber communicated by the hydroline 21 with pressure the cavity of the uncharged hydroaccumulus of the torus 19 is also small. Fluid from hydroline 7 is discharged through regulator 16, drain hydraulic line 20, valve 32, hydraulic line 31, device 11, hydraulic lines 8 and 9 into hydraulic system 6 and further into the hydraulic tank. At the same time, the charging of the hydroaccumulator 19 begins. The piston of the latter gradually compresses the spring, and the pressure in its pressure cavity rises in proportion to the spring force. This pressure, acting on the regulator 16, increases its setting, as a result of which the pressure it maintains in the hydraulic line 7 and the hydraulic cylinder 2 gradually increases.

At the end of charging of the hydroaccumulator 19 (stopping of its piston) the flow for filling the latter stops, which leads to a decrease in the differential pressure on the throttle 24, an abrupt increase in pressure in the hydroaccumulator and the closure of the regulator 16 (cessation of discharge into the hydroline 20). The activation of the hydraulic cylinder 2 is completed.

Next, the unlocking device 11 finishes its operation, the response time of which is selected with a slightly longer activation time of the hydraulic cylinder 2, and applies pressure to its output 12. This equalizes the pressure on both sides of the piston of the accumulator 19, and it discharges, i.e. under the action of the spring, the liquid is expelled from the pressure cavity through the choke 30 into the hydroline 31. In the discharge process, the spring creates in the pressure cavity of the hydroaccumulator of the torus excess

ten

81614b

pressure that also acts

on the gates of all regulators and contributes to the rapid return of the shutter regulator 16 to the closed position.

At the same time, the pressure from the outlet 12 of the device 11 through the hydroline 31 enters the check valve 32 and the latter closes the drain hydroline 20. If the valve 13 continues to remain in the on position, the pressure from the outlet 12 re-enters the hydroline 5 and turns it on. Now the mechanism 15 is again in the initial position and prepared for the next actuation, however, for this to happen, it is necessary to relieve the pressure from the hydraulic line 31, which locks the indicated mechanism in the closed position.

When another hydraulic cylinder is switched on, the unlocking of the mechanism occurs in this way due to the disappearance of the pressure at the outlet 12 of the device 1 1.

The most dangerous failure of the regulator 16 is the jamming of its shutter in the open position at the beginning of the second stage of the transmission,

15

20

25

0

0

for example, as a result of a foreign object (large metal shavings, etc.) along with the flow of fluid drained from hydroline 7 to hydroline 20. In this case, the pressure in hydroline 7 does not increase and the force of the hydraulic cylinder 2 is not enough to close the clutch that sticks it heats up quickly and can be worn out in a short time. However, in this device, as a result of locking the drain hydraulic line 20, the pressure in the hydraulic line 7 and the hydraulic cylinder 2 increases to a normal value, regardless of the state of the regulator 16, which significantly increases the safety of the mechanism 15 in operation.

Various design options are possible. Thus, in order to eliminate the effect of the operating regulator on idle, in addition to valve 32 or instead of it, individual check valves 33-35, shown in dotted lines, can be installed. At the inputs to the regulators 16-18, hydraulic compensators can be installed.

resistances (not shown). Other designs and schemes for connecting the separation valves 27-29, charging and discharging the hydraulic accumulator are possible.

five

0

19. In particular, mechanism 15 may have individual batteries of known design, etc.

The device can operate without valve 32, as well as valves 33-35, which are inserted to further improve safety.

Formula Invention

The smooth gearing mechanism of the transmission of the vehicle’s hydromechanical transmission, containing pressure regulators, the inputs of which communicate with the hydraulic cylinders of the inclusive transmissions, and the valve sub-valves through check valves and constant throttles communicate with the inputs, and

five

At least one hydroaccumulator, the pressure cavity of which is in communication with the subvalvular cavities of the regulator, and the spring cavity is made with water flow. the ability to connect to the output of the automatic unlocking of the torque converter by hydromechanical transmission, characterized in that, in order to increase efficiency by improving safety in operation, it is equipped with a hydraulic line that communicates the outputs of the regulators with the output of the automatic unlocking device of the torque converter, and at least one non-return valve installed in the hydraulic line, while the valve is oriented to the inlet to the regulators.

Claims (1)

The formula of the invention ^ A mechanism for smoothly switching gears of a hydromechanical transmission of a vehicle, comprising pressure regulators whose inputs are connected to the hydraulic cylinders of the gears, and the sub-valves, cavities through check valves and constant throttles communicate with the inputs, and at least one hydraulic accumulator, the pressure cavity of which is connected with the sub-valve cavities of the regulator and the spring cavity is made with air. the ability to connect a hydromechanical transmission torque converter automatic unlocking device output, characterized in that, in order to increase efficiency by increasing operational safety, it is equipped with a hydraulic line connecting the regulator outputs with the output of the torque converter automatic unlocking device and at least one non-return valve, installed in the hydraulic line, while the valve is oriented by the entrance to the regulators. Compiled by A. Barykov Editor I. Casarda Tehred M. Khodanich Corrector T. Malets Order 2060 Circulation 419 Subscription VNIIIPI State 113035, Committee for Inventions and Discoveries under the Civil Code of the USSR NT Moscow, J.-35, Raushskaya nab., D. 4/5 Production and Publishing Plant Patent, Uzhgorod, st. Gagarina, 101