RU2277478C1 - Planetary elastic clutch with adjustable fluid flow - Google Patents

Abstract

FIELD: transport engineering.

SUBSTANCE: invention can be used in transmissions of tractors and road-building machines under unstable motion conditions. Proposed transmission of vehicle has planetary reduction gear coupled with engine, pneumohydraulic accumulator, hydraulic pump mechanically coupled with one of links of planetary reduction gear. Fitted in pressure main lone are hydraulic distributor and additional three-dimensional member containing adjustable restrictor connected with variable rigidity pneumohydraulic accumulator. Drain main line of pneumohydraulic accumulator is connected through reduction valve with suction main line of hydraulic pump and drain main line of hydraulic distributor.

EFFECT: protection of engine and parts of power train from peak loads by means of reducing valve and from dynamic loads at starting from half, optimization of operation of engine, reduced specific consumption on fuel.

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Description

The invention relates to transport engineering and can be used in transmissions of tractors and road-building machines operating in unsteady driving conditions.

Known hydro-volume creeper reducer of a self-propelled machine, containing a gear reduction gear, sequentially installed in the kinematic chain of the transmission, connected to the gearbox with a hydraulic machine of constant working volume, in the pressure hydraulic line of which there is a flow regulator with a control element, a hydraulic tank [1].

A disadvantage of the known design is its complexity, the lack of damping and changes in the operating characteristics of the drive.

A transmission of a vehicle is known, comprising a planetary gearbox associated with an engine, a hydraulic accumulator, a hydraulic pump mechanically coupled to one of the planetary gearbox links, and a distributor, the first line of which is connected to the discharge line of the hydraulic pump, and the second with a drain [2].

The disadvantage of this design is the inability to protect the engine from a complete stop.

A device for reducing the stiffness of a vehicle’s transmission is known, which we have taken as a prototype, comprising a planetary gear, the reactive link of which is connected to an oil pump connected to a suction and pressure lines, pumping oil into a pneumatic accumulator, a gearbox connected to a driven planetary shaft, an oil tank [3].

The disadvantage of this device is the complexity of the design of the hydraulic system. The presence of three valves in one hydraulic line will not provide a smooth change in the fluid flow in the damper device. Slow emptying of the pneumohydraulic accumulator through the hydraulic pump sets it to reverse rotation, worsening the gear shift mode. The accumulated energy in the pneumatic-hydraulic accumulator does not return to the vehicle transmission.

The objective of the invention is to simplify the design and increase durability by reducing the wear of transmission parts, eliminating dynamic loads in the power transmission by smoothly changing the transmitted torque and expanding the functionality when installing the clutch in the transmission.

The technical result is the protection of the engine and power transmission parts from peak loads with the help of a pressure reducing valve and from dynamic loads when starting, that is, ensuring smooth starting using a throttle volume, optimizing engine performance and reducing specific fuel consumption.

The specified technical result during the implementation of the invention is achieved by the fact that it is equipped with an additional volume containing an adjustable throttle connected by a pressure line to a pneumohydraulic accumulator of variable stiffness. In this case, the drain line of the accumulator is connected through a pressure reducing valve to the suction line of the hydraulic pump.

The drawing shows a hydrokinematic diagram of a clutch in a transmission drive. The proposed coupling contains a flywheel 1, to which bolts 2 are mounted a ring gear 3, inside of which a carrier 4 is located, connected to the driven shaft 5 of the clutch, the satellites 6 are engaged with the sun gear 7, which is connected to the drive of the hydraulic pump 8. The hydraulic pump has a suction line 9 and injection 10, in which the distributor 11 and the drain line 12 are mounted, the pressure line 13 is connected to the throttle volume 14 and the adjustable throttle 15, the pneumohydraulic accumulator 16 is connected to the drain line 17 with a pressure reducing valve 18 and with a suction line 9.

The work of the proposed clutch in the drive transmission of the vehicle is as follows.

The torque from the flywheel 1 is transmitted to the ring gear 3, it starts to rotate and transfers the rotation to the satellites 6. Driving the sun gear 7 and the oil pump drive 8, which, while rotating, pumps oil into its suction line 9 from the vehicle’s hydraulic system. It under pressure enters the discharge line 10 and goes to the distributor 11. If the distributor is closed, the oil goes to the drain to the line 12 connected to the drain line 17 of the pneumohydraulic accumulator 16 and the suction line of the hydraulic pump 9. When the valve 11 is closed, the clutch is in off, the vehicle is not propelled, even if the gear is engaged. If the distributor 11 is open, then the oil enters the line 13 and an additional throttle volume 14. It is filled until the oil pressure reaches the response value of the throttle 15, which opens the access of oil to the pneumohydraulic accumulator 16. At this time, the first stage of acceleration of the transport begins facilities. The pump delivers oil until the oil pressure reaches a value that balances the moment of the sun gear acting on the motor side. In this case, the pump 8 will stop, the sun gear 7 will also stop, but the satellites 6 will begin to rotate around its axis, circling the sun gear 7, and transmit the moment through the carrier 4 to the power transmission shaft. The vehicle will begin to move forward.

With a significant increase in the hook load, a pressure reducing valve 18 enters into operation, which opens the access of oil from the pneumohydraulic accumulator 16 to the drain to the line 17. In this position, the engine is in overload mode, but does not stall, and the vehicle stops. Therefore, the operator will be required to shift to a lower gear. When the distributor 11 is switched to the "discharge" position, the oil from the throttle volume 14 is discharged to the line 12 connected to the suction line 9 of the hydraulic pump. Under the action of the vacuum created by the hydraulic pump 8, the throttle volume is quickly released for further filling with oil when shifting the gear.

The throttle volume in combination with a pneumatic-hydraulic accumulator and a pressure reducing valve allows protecting the engine and transmission from peak dynamic loads not only at the beginning of acceleration, but also during steady-state movement, preventing the engine from stopping completely using a pressure reducing valve.

Information sources

1. Autosvid. USSR No. 1482829 A1, cl. In 60 K 17/10, 1989. Hydro-volume creeper reducer of a self-propelled machine. Declared September 16, 87. Published on May 30, 89. Bull number 20.

2. Autosvid. USSR No. 1592173 A1, class B 60 K 17/10, 1988. Transmission of a vehicle. Declared 12.12.88. Published on September 15th, 1990. Bull. Number 34.

3. Autosvid. USSR No. 1062035 A, cl. In 60 K 17/10, 1978. A device for reducing the stiffness of a vehicle’s transmission. Declared 09/07/82. Published on December 23rd, 1983. Bull. No. 47.

Claims (1)

A vehicle transmission comprising a planetary gearbox connected to the engine, a pneumatic hydraulic accumulator, a hydraulic pump mechanically connected to one of the planetary gearbox links, and a control valve installed in the pressure manifold, characterized in that an additional volume is installed in the pressure manifold containing an adjustable throttle connected to a pneumatic-hydraulic accumulator of variable stiffness, while the drain line of the pneumatic-hydraulic accumulator is connected through a reduction nny valve with the suction line of the hydraulic pump and the drain line of the control valve.