JPS60143179A - Power steering for car - Google Patents

Abstract

PURPOSE:To facilitate manufacture of memory and read-in of data by writing control data of a plurality of different type of cars into a memory provided in a control unit then selecting the car type control data from said memory with correspondence to the car type and using. CONSTITUTION:Memory circuit 63 is a ROM written with a plurality of different car type control data such as FF car, FR car, biaxial truck, etc. in addition to data required for a power steering 10. When steering the front wheel, a switch of a selection signal generating circuit 73 in a car type control data selection circuit 66 is operated to select data corresponding with the car type from the memory circuit 63. With correspondence to the selected data, a central processing circuit 64 will control a reaction regulation valve with correspondence to the car speed.

Description

[Detailed Description of the Invention] This invention relates to a power steering system used in a vehicle;
In particular, it relates to speed-sensitive power steering with a hydraulic reaction chamber.

In this type of power steering, the reaction force chamber is connected to the suction side of the oil pump, and a reaction force adjustment valve adjusts the amount of pressure oil released from the reaction force chamber to the suction side of the oil pump. The reaction force adjustment valve is also controlled to open and close by a control unit that changes the current to the reaction force adjustment valve according to the vehicle speed sensor signal. Today, with so many desk types being manufactured, sold, and in use, it is important to store the optimal control data for each control unit. only memory circuit, i.e., read-only memory (
ROM) was required, and the production and data loading work was complicated.

An object of the present invention is to write control data for a plurality of different table types in a memory circuit, that is, a memory dedicated to G output, which is provided in the control unit in advance, and to transfer the table type control data from the memory according to the type of the table. The purpose of the present invention is to provide a power steering system for use in vehicles that facilitates the selection and use of memory and data writing operations.

With these issues in mind, the power steering used in the vehicle of this invention includes an oil pump, control system,
The valve includes a hydraulic reaction type control valve with a reaction force chamber and a hydraulic cylinder to be steered, and the reaction force adjustment passage connects the reaction force chamber of the control valve to the suction side of the oil pump. and a reaction force regulating valve is disposed in the reaction force regulating passage so as to regulate the pressure in the reaction chamber of the control valve, and the control unit has an input and an output circuit, a plurality of different Read-only memory circuit including writing of desk control data (
ROM), a table-type control data selection circuit, an arithmetic circuit, and a control circuit that select and use the table-type control data in the storage circuit (ROM) corresponding to the table type (if the vehicle speed sensor is electrically connected to the controller, and based on the selected desk control data, calculates according to the input signal from the vehicle speed sensor, opens and closes the reaction force adjustment valve, and controls the pressure in the reaction force chamber. It is configured to do this.

Hereinafter, preferred specific examples of the power steering system used in a vehicle according to the present invention will be described with reference to the drawings.

Figures 1 and 2 schematically illustrate an embodiment 10 of flow steering (used in the vehicle of the present invention) applied to a truck.

In order to steer the front wheels, the power steering 10 uses a speed-sensitive reaction force and is embodied in a linkage type, including a knuckle arm (not shown) and a drag link (not shown). , link lever (not shown),
Steering wheel (not shown), manual steering gear box (not shown), pitman arm (not shown), convenzating rod (not shown), oil pump 11, flow control 0 valve 12, control valve 13, power cylinder 14 disposed between its link lever and its controlling rod, reaction force adjustment passage 15, reaction force adjustment valve 16, and its reaction force. A control unit 17 that drives and controls the regulating valve 16 and a vehicle speed sensor 1
It consists of 8.

Oil pump 11 is mounted on the truck.

It is powered by a built-in internal combustion engine (not shown).
It is arranged in the hydraulic piping 19 in the hydraulic circuit of the power cylinder 14, and sucks up oil in an oil reservoir (not shown), so that a discharge amount of pressure oil approximately proportional to the rotation speed of the internal combustion engine can be obtained. It is configured. Of course, the oil pump 11 is configured similarly to the oil pump used in existing power steering.
A description of its configuration will be omitted.

7o-・Control valve 12 kHl” 7-・
In the hydraulic circuit of the cylinder 14, the hydraulic pipe 19.20
It is located in

The flow control valve 12 is connected to the discharge side of the oil pump 11.
1s A casing including a control valve port 22 connected to the pressure port 32 side of the control valve 13 and a suction port 23 connected to the suction side of the oil pump 11, and a reciprocating slide inside the casing. movably arranged oil return
Control spool and its pump 0
・Adjust the flow rate of the pressure oil sent to the port 21 side, send a predetermined flow rate to the control valve I- port 22 side, and send the surplus flow from the suction port 23 to the oil pump 11. I try to return it to the suction side. Of course, the flow control valve 1zc, existing (1)c') - Since it has the same structure as the flow control pulp used for steering, a detailed explanation of its structure will be omitted. .

The control pulp 13 is configured as a speed-sensitive type equipped with a reaction force chamber that changes the reaction force according to the vehicle speed, and is incorporated into the power cylinder 14 of the vehicle. The valve is operated by the steering wheel via the steering gear box, and in the hydraulic circuit of the power cylinder 14, it is arranged in the hydraulic line 19, 20, and is discharged from the oil pump 11, and the flow control
The pressure oil whose flow rate is adjusted by the pulp 12 is sent to the power cylinder 1.
4, and also returns the pressure oil worked by the power cylinder 14 to the suction side of the oil pump 11, which includes a pulp body 24 and a control pulp spool equipped with a reaction chamber 39 inside. 25, a spool shaft 26, a pair of reaction plungers 27, 28, a pair of plunger stoppers 29, and a reaction spring 3°.

The pulp body 24 is connected to the power cylinder 14
It is built into the cylinder body of the spool and
A bore 31 is formed inside.

Also, the pulp body 24 is exposed to the pressure I? - port 32, a pair of cylinder ports 33, 34, a pair of tank ports 35.3B
, a reaction force port 37, and its flow control.
Pour the adjusted pressure oil into the pulp 12
To supply the cylinder chamber 54,55 of the cylinder 14, the pressure I? - the port 32 on the supply side of the hydraulic line 19, the cylinder port 33.34 on the cylinder side of the hydraulic line 19, 20, and the tank
Bows 1, 35 and 36 are connected to the hydraulic piping 20, respectively.

The roll pulp spool 25 forms a reaction chamber bore 38 that is open at both ends so as to form a reaction chamber 39 inside, and is arranged in the spool bore 31 so as to be able to reciprocate and slide. ing.

The control pulp spool 25 also has a large-diameter planter bore 40 at one end of the reaction chamber bore 38.
At the other end of the reaction chamber bore 38 is a small diameter 7° run bore 4.
1 respectively, and the pressure is 1? -1-32 is provided with a pressure communication line =-442 which communicates the reaction force chamber 39 with the reaction force chamber 39, and a reaction force relief port 43 which connects the reaction force chamber 39 with the reaction force port 37 is provided.

To Sara, Seo's Control Pulp Spoiler 2
5 connects the pressure port 32 to the cylinder J? It is provided with ring grooves 44 and 45 that form a valve oil chamber that is switchably connected to the ports 33 and 34.

The spool shaft 26 has one end passed through the control pulp spool 25, and the spool shaft 26 is inserted into the spool 25 so as to slide the spool 25 back and forth into the spool bore 3.I. Both; fusion (
The spool 25 is provided with a pair of spool stops 46 for fixing the spool 25 in position, and the other end is connected to a connecting rod.

Furthermore, in detailing the fixing structure of the spool 25, the spool shaft 26 is
The frame 0-rule is located between the stoppers 46.
A spacer 47 fixed to one end of the spool shaft 26 by a sleeve-shaped spacer 47 ID-coupled to one end of the shaft 26 and a nut 48 screwed to one end of the spool shaft 26. Insert the spool 25 between the stoppers 46 and fix the spool 25.

These spool stoppers 4G are formed in a plate shape, and have two small holes 49 opened in the stopper surface at predetermined positions and spaced apart from each other by a predetermined distance.

The reaction plungers 27 , 28 are formed in large diameter and small diameter versions, with the large diameter reaction plunger 27 sliding reciprocally into the large diameter plunger bore 40 and spacer 47 on the spool shaft 26 . can be fitted together, and
The small-diameter reaction force plunger 28 is reciprocally slidably fitted into the small-diameter sylanger bore 41 and the spacer 47 on the spool shaft 26, and its control pulp
A reaction force chamber 39 formed within the spool 25 is closed.

In this way, the reaction force plungers 27, 28 are installed 31 in the large diameter one and the small diameter one.
In the steering 10, its power cylinder 14
When the steering wheel retracts, the driver feels that the steering is heavy,
In addition, when the power cylinder extends and moves, the driver feels that the steering is soft.In other words, there is a difference in the left and right steering forces, so the steering force for right and left turns is equally distributed. There is something to do.

The pair of sylanger straights 29 each consist of two pins protruding from both inner end surfaces of the spool head 310, and these pins pass through the small holes 49 of the spool stopper 46, and are inserted into the corresponding large diameter and Abut the tip of the small diameter reaction force plunger 27.28, and press the spool bore 3.
Those reaction force plungers 27.28 towards the inner end face of 1
With the movement of the spool shaft 26, the reaction force spring 3o cooperates with the reaction force plunger 27, 28 to give a pump upward movement,
The oil filled in the reaction force chamber 39 is compressed, and the spool
Shuff (changes the reaction force felt by 26.

The reaction spring 3o, those anti-kabujinja 27
．． 28, arranged around the spool shaft 26, i.e. the spacer 47, which imparts a pumping action to the counterforce blunters 27. , which functions as a centering spring.

The power cylinder 14 includes a cylinder body 5o pivotally connected to a link lever, and a pair of cylinder chambers 54 in a cylinder bore 53 of the cylinder body 50.
, 55, the power piston 51 is reciprocally slidably disposed in the cylinder bore 53, and one end is fixed to the power piston 51, and the other end is pivotally connected to the chassis side. It consists of a rod 52 with ports 56,57 connected to hydraulic lines 19,20 and driven by pressure oil controlled by its control valve 13.

The reaction force adjustment passage 15 consists of a pipe connecting a reaction force port 37 formed in the valve body 24 of the control pulp 13 to the hydraulic pipe 20, and a reaction force relief port 43.
When the pressure oil in the reaction force chamber 39 is connected to the reaction force port 37, the pressure oil in the reaction force chamber 39 is released to the suction side of the oil I pump 11, but the amount of oil released is also controlled by the reaction force adjustment valve 1G. .

The reaction force regulating valve 16 includes a valve body 58 having a spool chamber (not shown) and a pair of ports (60, 61) in communication with the spool chamber, and a reciprocating slide within the spool chamber. a spool (not shown) movably arranged to vary the cross-sectional area of the passage within the spool chamber in response to the reciprocating sliding thereof; and an electric servo motor 59 for driving the spool; Depending on the running speed of the trunk, the spool is slid back and forth in the spool chamber to change the passage cross-sectional area in the spool chamber and adjust the flow rate of pressure oil flowing between the ports 60 and 61. , its control bano v7
'13 is configured to change the reaction force generated by the pressure oil in the reaction force chamber 39.

More specifically, this reaction force adjustment valve 16 widens the passage cross-sectional area when the truck travels at low speed, and narrows the passage cross-sectional area when the truck travels at high speed. The servo motor 59 drives the spool. Of course, that servo motor 59
is driven and controlled by a control unit 17 based on a signal from a vehicle speed sensor 18.

The control unit 17 has an input side electrically connected to a vehicle speed sensor 18 , and an output side electrically connected to an electric servo motor 59 of the reaction force regulating valve 16 , and receives a signal from the vehicle speed sensor 18 . It controls the output signal, that is, the output current, to the servo motor 59 according to the input and output circuit 62, and the memory circuit 6.
3, a central processing circuit 64 and a power supply circuit (not shown); the central processing circuit 64 includes an arithmetic circuit 65,
It consists of a desk-type control data selection circuit 66 and a control circuit 67, and is also provided with an address bus, a data bus, and a control unit, and is further provided with a memory circuit 63 and an interface circuit for external equipment. .

The memory circuit 63 is a read-only memo+7 (ROM
), in addition to the data necessary for the wheel steering 10, there are several different table-type control data, such as
, '1 Table-type control data for front-engine front-drive passenger cars, front-engine rear-drive passenger cars, two-axle trucks, three-axle trucks, buses, etc. is 68,69,70° 71.72. ...
It is written. That is, it is stored.

The desk control data selection circuit 66 also selects a plurality of desk control data 68, 69 written in the storage circuit 63.
, 70, 71, 72. . . , and includes a selection signal generation circuit 73 equipped with a large number of switches. Of course, the selection signal generation circuit 73 can also be configured on the board so that the contacts of these switches are selectively connected by jump wires, and if configured in that way, the The selection signal generation circuit 73 becomes simpler.

The vehicle speed sensor 18 detects the traveling speed of the truck, and is arranged on the output shaft of the transmission mounted on the truck.

The vehicle speed sensor 18 is, of course, as described above.
It is electrically connected to the input circuit 62 of the control unit 17 and sends a signal for controlling the opening and closing of the reaction force regulating valve 16 to the control unit 17.

Next, we will discuss the front wheel steering of the truck by the above-mentioned power steering 10 when the truck is running.
, the selection signal generation circuit of the table-type control data selection circuit 66 operates a switch, and the table-type control data 68, 69, 70, 71, written in the memory circuit 63 is read.
72. . . . selects the table-type control data for that truck to be usable.

As such, once the desk control data for that truck has been selected, the control unit 17 inputs the signal from the vehicle speed sensor 18 and outputs the signal to the electric servo motor 59 of the reaction force regulating valve 16. It is ready to give and adapt to steering wheel operations.

Further, the flow rate of pressurized oil from the oil pump 11 is adjusted by a flow control valve 12, and at a predetermined flow rate,
It is sent to the pressure port 32 of the control valve 13.

The pressure oil sent to the pressure port 32 is h as shown in FIG.
If the control valve sprue 25 is in the neutral position, as shown in FIG.
The steering wheel is steered to push or pull its spool shaft 26 in either direction via the manual steering box, pitman arm, and steering londra, and its control If the valve spool 25 is slid in the direction of the movement of its spool shaft 26, then in response to the movement of the control valve spool 25, 7 the pressure oil will move up the cylinder side of the hydraulic line 19.20. Through the cylinder chamber 54.55 of the power cylinder 14
and the reaction force chamber 39.

The reaction force against the steering is the pressure in the reaction force chamber 39 adjusted by the reaction force adjustment valve 16 and the reaction force spring 30.
given by.

In such a power steering IO operation,
If the truck is driven at low speed, the sonocontrol unit 17 receives a signal from the vehicle speed sensor 18;
The output signal, that is, the output current, which is compared and calculated based on the input signal, is sent to the electric servo motor 59 of the reaction force adjustment valve 16, so that the spool is slid in the reaction force adjustment valve 16, and the spool The passage within the chamber is opened relatively wide.

Therefore, the pressure oil in the reaction force chamber 54 is released from the reaction force relief port 4.
3. Flows into the reaction force port 37, and further flows into the reaction force adjustment passage 15.
, flows through the hydraulic piping 31 to the suction side of the oil pump 11, so the pressure oil in the reaction chamber 39 does not provide a large resistance to the sliding of the reaction force plunger 27 or 28, and its low-speed running is prevented. Steering of time is done with a small amount of operating force.

Of course, if the truck is steered when stopped, the traveling speed is zero and the passage of the reaction force regulating valve 16 is opened to the maximum, so the pressure in the reaction force chamber 39 is close to atmospheric pressure. 1.7 +, etc. can be performed with a small operating force.

If the truck is running at high speed, the control unit 17 inputs a signal from the vehicle speed sensor 18, and outputs the output signal, that is, the output current, which is compared and calculated based on the input signal. The electric servo motor 59 of the force regulating valve 16 is fed so that the spool is slid in the reaction force regulating valve 16 and the passage in the spool chamber is narrowed open.

Therefore, the pressure oil in the reaction force chamber 39 is
6 makes it even more difficult to return to the suction side of the oil pump 11 (therefore, the pressure oil in the reaction force chamber 39 becomes a great resistance to the sliding of the anti-cuff ginger 27 or 28, As a result, steering at high speeds requires a relatively large operating force.As such, steering at high speeds requires a relatively large operating force, improving driving stability. be done.

Further, when the truck is running at low speed, high speed, stationary, turning, etc., the power steering 10 is operated as described above, and the reaction force plunger 27 is operated as described above.
．． 28 has a large diameter and a small diameter, so in the power steering 10, when the power cylinder performs a retraction operation and an extension operation, the difference between the right turning operation force and the left turning operation force is extremely large. In other words, the right and left turning steering forces are equalized.

As a result, this power steering 10 relieves the driver from physical fatigue caused by truck steering.

According to the present invention, a plurality of different desk-type control data are written in advance in the read-only storage circuit, that is, the memory, provided in the control unit.
Depending on the table type, the table type control data selection circuit can select and use the table type control data from the memory, thereby eliminating the need to manufacture the memory for each table type and write the data. As a result, the production of the memory and the data embedding work become easier, and the production cost is reduced.

As mentioned above, from the specific examples of the present invention explained with reference to the drawings, it will be easy for those who have ordinary knowledge in the technical field to which the invention pertains to make various modifications and changes. Furthermore, the content of this invention can easily be converted into an embodiment essentially the same as that invention, which satisfies essentially the same problem as that invention and achieves the same effect as that invention. will be replaced.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing a concrete example of the power steering of the present invention which is embodied as a linkage type and is applied to a truck, and FIG. 2 shows the power steering shown in FIG. 1. The control unit (already described) used in
Pump, 12...Flow control pulp, 1
3...Control pulp, 14.../F quail
Cylinder, 15... Reaction force adjustment passage, 16... Reaction force V,
a Valve regulator, 17... Control unit, 18...
・Vehicle speed 9

Claims (1)

[Claims] In a steering device that includes an oil pump, a flow control valve, a hydraulic reaction type control valve 6 equipped with a reaction force chamber, and a power cylinder, the reaction force adjustment passage is the control valve. a control valve communicating a reaction chamber of the valve with a suction side of the oil pump; a reaction control valve disposed in the reaction control passage to adjust the pressure in the reaction chamber of the control valve;・The unit has input and output circuits, a read-only memory circuit (ROM) containing a plurality of different table-type control data writes, and a memory circuit (ROM) corresponding to the table type.
M) comprises a table-type control data selection circuit, an arithmetic circuit, and a control circuit that selects and makes available the table-type control data, is electrically connected to the vehicle speed sensor, and is based on the selected table-type control data. A power steering system used in a vehicle is characterized in that the power steering system calculates according to an input signal from the vehicle speed sensor, opens and closes the reaction force adjustment valve, and controls the pressure in the reaction force chamber.