RU2492092C1 - Hydraulic drive with flow alarm valve - Google Patents

Abstract

FIELD: transport.

SUBSTANCE: invention relates to automotive industry. Hydraulic drive with alarm valve comprises primary hydraulic drive with engine-driven primary pump and emergency hydraulic pump with motor-driven check valve. Primary pump pressure line incorporates flow alarm valve to be connected to emergency pump pressure line. Alarm valve is composed of a check valve incorporating contactless Hall transducer. Alarm valve body has two inlet channels and one discharge channel and through bore with check valve seat. Hollow rod with check valve gate is arranged in said bore to displace in inside the cover fixed in the body through bore. Spring to rest on cover end face and press check valve gate to its seat is fitted inside the rod on one side. Permanent magnet to interact with Hall transducer without direct contact is arranged on opposite side of rod cavity. Hall transducer is arranged inside body bore is aligned with the rod and coupled with emergency pump drive motor.

EFFECT: higher reliability.

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Description

The invention relates to transport engineering, in particular to hydraulic vehicle control systems, in particular to devices transmitting a signal for automatically turning on emergency steering.

A hydraulic vehicle control system is known, comprising an auxiliary hydraulic pump with an electric drive, electrically connected to a power source and a control element, and hydraulically to an input line of an OR valve and a hydraulic tank, and a pressure sensor hydraulically connected to a discharge line of the main hydraulic pump and electrically connected with electric drive and control element of auxiliary hydraulic pump, as well as sectional distributor with electric control, input ma on lines which is connected to a distributor of power steering, and the output line - with a hydraulic tank (1).

The disadvantages of this emergency steering enable circuit are increased pressure losses to maintain pressure sensor readings within specified limits; false positives due to a decrease in viscosity with increasing temperature, which can lead to premature discharge of the emergency drive battery; possible failures in the operation of the pressure sensor at a low temperature and reduced pump performance due to its wear, which will lead to uncontrollability of the vehicle with an insufficient flow of working fluid in the main steering circuit.

A hydraulic vehicle control system is also known, including a main hydraulic actuator with a main pump and an emergency hydraulic steering gear, including an auxiliary pump with a non-return valve connected to an electric motor of the electric actuator, the signal to which is transmitted from a pressure sensor hydraulically connected to the discharge line of the main hydraulic pump and electrically connected to the electric drive (2). The auxiliary steering emergency hydraulic pump works when the pressure in the pressure line of the main pump is below a predetermined reserve level.

The disadvantages of the known emergency steering system, as well as the first analogue, are increased pressure losses to maintain the pressure sensor within the specified limits; false alarms due to a decrease in viscosity with increasing temperature, as well as possible failures in the operation of the pressure sensor at low temperature and reduced pump performance due to wear.

The objective of the invention is to increase the reliability of driving a vehicle by receiving a guaranteed signal that there is no flow in the pressure line of the main pump to activate the emergency steering drive.

The solution to this problem is achieved as follows.

The hydraulic drive contains a main hydraulic actuator with a main pump and an emergency hydraulic actuator, which includes an auxiliary pump with a check valve with the possibility of switching on from the electric motor while lowering the flow rate of the working fluid in the pressure line of the main pump to a predetermined reserve level. The signal to the auxiliary pump is transmitted according to the claimed invention from the flow signal valve, made in the form of a non-return valve using a non-contact Hall pressure sensor in a liquid medium under pressure and installed in the pressure line of the main pump with the possibility of connecting to the pressure line of the auxiliary pump. A through bore with a non-return valve seat is made in the body of the flow signal valve, which contains two inlet and one output channels, in which a hollow rod with a check valve shutter is installed, which can be moved in the cavity of the housing cover. On the one hand, the rod is spring-loaded, and on the other hand, a permanent magnet is installed with the possibility of interaction with a Hall sensor located in the bore of the housing and transmitting a signal to the electric drive.

Thus, the application in the hydraulic system of the claimed design solution allows with sufficient accuracy regardless of the temperature and viscosity of the working fluid to determine the presence of flow in a given range.

Figure 1 presents a schematic diagram of a hydraulic circuit hydraulic drive with a signal valve flow.

Figure 2 schematically shows a flow signal valve (when the auxiliary pump is turned on).

The hydraulic actuator with a flow signal valve contains a main drive with a main pump 1 driven by an internal combustion engine and an emergency drive with an auxiliary pump 2 driven by an electric motor 3, a flow signal valve 4, a check valve 5 for connecting an auxiliary pump 2, a pressure line 6 of the main pump 1, the pressure line 7 of the auxiliary pump 2, in which the check valve 5 is installed, the pressure line of the consumers 8. The signal valve flow 4 installed in the pressure line 6 of the main pump and 1 with the possibility of connection with the pressure line 7 of the auxiliary pump 2, comprises a housing 9 with inlet channels 10 and 11 connected respectively to the pressure line 6 of the main pump 1 and to the pressure line 7 of the auxiliary pump 2, and to the output channel 12 connected to the pressure consumer line 8. In the housing 9, perpendicular to the input 10, 11 and output 12 channels, a bore 13 is made in which a hollow rod 14 with a check valve 15 is installed. The bore 13 of the housing 9 is made with a seat 16 of the check valve. The rod 14 is placed in the cavity of the cover 17 installed in the bore 13 of the housing 9, and is spring-loaded relative to it by a spring 18, which is installed in the cavity of the rod 14 and abuts against the end face of the cover 17. At the same time, a permanent magnet 19 is placed in the cavity of the rod 14, and on its side, a Hall sensor 20 is installed in the bore 13, while the magnet 19 and the Hall sensor 20 are placed with a gap with the possibility of contactless interaction.

The hydraulic drive operates as follows.

When operating in normal mode, the working fluid from the pressure line 6 of the main pump 1 enters through the input channel 10 of the signal valve flow 4. At a given flow rate, the flow of working fluid acts on the stem 14 with the valve 15 of the check valve, which moves in the cavity of the cover 17, compressing the spring 18 while the check valve 5 is in the locked position. Thus, the working fluid enters the output channel 12 of the signal valve flow 4, connected with the pressure line of consumers 8.

In an emergency, when the flow rate of the working fluid in the pressure line 8 of the main pump 1 drops below a predetermined backup level, the spring 18 is opened and moves the rod 14 relative to the cover 17, while the check valve 15 rests on the non-return valve seat 16, blocking the pressure line 6 of the main pump 1 from the pressure line of consumers 8. At the same time, the magnet 19 interacts with the Hall sensor 20, which leads to the appearance of a signal to turn on the auxiliary pump 2. The electric motor of the electric drive 3 includes an auxiliary CO 2, the check valve 5 is activated, opening the flow of the working fluid from the pressure line 7 of the auxiliary pump 2 through the input channel 11 to the output channel 12 of the flow signal valve and then to the pressure line of consumers 8.

Thus, the claimed design is industrially applicable and solves the problem of increasing the reliability of steering the vehicle.

Information sources

1. Patent RU 2248295 C1, publ. 03/20/2005;

2. Catalog "Components of hydrostatic control", Danfoss, NK.20.V1.50, p. 42

Claims (1)

A hydraulic actuator with a flow signal valve, comprising a main hydraulic actuator with a main pump driven by an engine and an emergency hydraulic actuator, including an auxiliary pump with a non-return valve, connected to the electric actuator with the possibility of switching on from the electric motor while lowering the flow rate of the working fluid in the pressure line of the main pump to a predetermined reserve level, characterized in that in the pressure line of the main pump there is a flow signal valve with the ability to connect to the pressure line of the auxiliary a linear pump, made in the form of a non-return valve using a non-contact Hall sensor in a liquid medium under pressure in the body of the flow signal valve containing two inlet and one outlet channels, a through bore is made with a non-return valve seat, in which a hollow rod with a non-return valve shutter is placed, installed with the possibility of movement in the cavity of the lid, mounted in the through bore of the housing, while in the cavity of the rod on one side there is a spring resting against the end face of the lid and installed with the possibility of by pressing the shutter of the non-return valve to its seat, and on the other hand, a permanent magnet with the possibility of contactless interaction with the Hall sensor installed in the housing bore coaxially with the rod and connected to the auxiliary pump electric drive.

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