JPS59118574A - Power steering gear for vehicle - Google Patents

Abstract

PURPOSE:To enable smooth steering while obtaining an always appropriate reaction force, by dividing reaction force chambers on both the sides of a control valve to provide a pair of auxiliary reaction force chambers and by controlling the quantity of supplied pressure oil to the auxiliary reaction force chambers depending on the quantity of the steering, the speed of a vehicle and the angular velocity of its yaw. CONSTITUTION:A power steering gear 10 comprises an oil pump 11, a flow control valve 12, a control valve 13 and a power cylinder 14. A pair of reaction force chambers 38, 39 are provided on both the sides of the control valve 13. The reaction force chambers 38, 39 are divided so that a pair of auxiliary reaction force chambers 42, 43 are provided. An orifice 44 is provided between the port 16 of the flow control valve 12 and the pressure port 20 of the control valve 13. A passage upstream to the orifice 44 is connected to the auxiliary reaction force chambers 42, 43 through control passages 45, 46, 47 among which an auxiliary reaction force control valve 48 is installed. An actuator 55 for the control valve 48 is regulated by a controller 56 depending on the outputs of a steering quantity sensor 68, a vehicle speed sensor 69 and a yaw angular velocity sensor 70.

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to improvements in power steering used in vehicles.

Power steering wheels commonly used in vehicles, oil pumps, flow control pulps, control pulps with reaction chambers on both sides of the control pulp spool, power 7 cylinders and other 9 cylinders. , the flow control pulp adjusts the flow rate of pressurized oil sent from the oil pump, and the control pulp adjusts the flow rate of the pressure oil sent from the oil pump, and the control pulp adjusts the flow control according to the reciprocating sliding of the control pulp spool.・The direction of the pressure oil sent to the valve-carrying sono-no-quare cylinder is controlled to operate the power cylinder, and the structure is designed to facilitate steering while providing an appropriate reaction force, that is, a feeling of response.

In addition to such a moderate reaction force, it is also required that the vehicle's path follows the steering operation without delay.In other words, the control pulp spool is required to move back and forth in response to the rotation of the steering wheel. There is a growing demand for less delay in sliding motion.

However, in reality, there has been a tendency for movement delays in the reciprocating sliding of the control pulp spool due to variations in the installation of the parts that make up the power steering and looseness in the operating force transmission system.

Therefore, when the vehicle is steered by rotating the steering wheel, there is a delay in the actual steering of the wheel axle, so it takes a long time to become proficient at driving, and it is always necessary to anticipate the delay in operation as described above. This required careful steering, which made driving nerve-wracking and tended to be tiring.

In addition, when designing a vehicle, priority is given to economy, such as loading efficiency and cabin space. - Maneuverability and stability were impaired, and in some cases, plans to develop new vehicles had to be abandoned.

An object of the present invention is to always cause the control pulp spool to reciprocate properly in response to the rotation of the steering wheel, and to prevent delays in the operation of the control pulp spool. By reducing changes in spool sensitivity and operating the war cylinders appropriately, we have made steering easier while obtaining an appropriate amount of reaction force, and we have prioritized economy such as loading efficiency and passenger space stiffness. To provide a steering wheel for use in a vehicle, which obtains excellent maneuverability and stability and enables safe driving through easy steering operation when applied to the vehicle.

With these issues in mind, /F used in the vehicle of this invention
Flow steering consists of an oil pump, flow control pulp, control pulp with reaction chambers on both sides of the control pulp spool,
A pair of auxiliary reaction force chambers are separated from the reaction force chamber and formed on both sides of the control pulp spool. A control pulp port of the control pulp is provided between the pressure port of the control pulp of the control pulp, and further, an auxiliary reaction force control passage connects the upstream side of the throttle to the pair of auxiliary reaction chambers, Moreover, an auxiliary reaction force control valve is provided in the auxiliary reaction force control passage, and adjusts the amount of pressure oil sent to the pair of auxiliary reaction chambers according to vehicle speed, steering speed/degree, and yaw angular velocity. is configured to do so.

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

The figure shows a specific example 1 of A' flow steering used in the vehicle of this invention applied to a cab-over type truck.
0 is shown schematically.

The power steering lO is oil pump 11
Flow control pulse 7"12, control pulp spool 2.9 and reaction chambers 38 on both sides,
It is composed of a control pulp 13 and a nower cylinder 14, each having a control pulp 39, and a nower cylinder 14 for steering.A pair of auxiliary reaction force chambers 42 and 43 are separated from the reaction force chambers 38 and 39, - Both sides K of the spool 29 are formed respectively, and the aperture 44 is used to control the flow of the pulp 12 through the control port 16 of the pulp 12 and the control pulp 13.
Further, auxiliary reaction force control passages 45, 46, 47 communicate the upstream side of the throttle 44 with the pair of auxiliary reaction chambers 42 and 43, respectively,
Moreover, an auxiliary reaction force control valve 48 is provided in the auxiliary reaction force control passages 45, 46, and 47, and according to the vehicle speed steering speed and yaw angular velocity of the cab-over type truck,
It is configured to adjust the amount of pressure oil sent to the pair of auxiliary reaction chambers 42 and 43.

The oil pump 11 is driven by an internal combustion engine (not shown) mounted on the Cab Oats Z type truck, and sucks up the pressure oil in the oil reservoir 67.
It is constructed so that a discharge amount of pressure oil can be obtained that is approximately proportional to the rotational speed of the internal combustion engine.

The oil pump 11 is configured similarly to an oil pump used in an existing power steering system, so a description of its configuration will be omitted.

Flow・Control pulp 12 C、So(D Pump port 15 connected to the discharge side of the oil pump 11, Control pulp port 16 connected to the pressure port 20 side of the control pulp 13 (described later)
, and a suction yr? connected to the suction side of the oil pump 11. -) a casing comprising 17 and an oil return control spool (not shown) disposed reciprocally slidably within the casing;
For example, by adjusting the flow rate of the pressure oil sent to the pump port 15 side, the predetermined flow rate can be controlled by
It is configured to send the excess flow to the pulp port 16 side and return the surplus flow from the suction port 17 to the suction side of the oil pump 11, that is, to the oil reservoir 67 side.

SonoFlow Control Pulp 12 is a
Since the structure is similar to that of flow control pulp used for power steering, a detailed explanation of its structure will be omitted.

Control pulse 7' 13 c, spool chamber 19, -t (7) Control pulp of flow control pulp 12, f - 16 Pressure port 20 connected to stool chamber 19 on the side, its spool an exhaust port 21 connecting the chamber 19 to its oil reservoir 67 side, and a power cylinder
Control pulp casing 18 with ports 22, 23, 24, its pressure port 20 connected to its discharge port 211, and its pressure cylinder port 2
2, 23.

a control pulp stool 29 reciprocally slidably disposed within the stool chamber 19 for switching connection to the spool chamber 24; a pair of reaction force chambers 38 and 39, and a pair of auxiliary reaction force chambers 42 and 43 formed on both sides of the control pulp stool 290 and separated from the reaction force chambers 38 and 39, respectively. It is well structured.

Of course, ring grooves 27, 28 are formed in the spool chamber 19, respectively, in communication with the pressure and discharge ports 20, 21.

ti,-to When the control pulp spool 29 is placed in the neutral position, lands 30.33 are formed around both ends of the control pulp spool 29 located outside the ring groove 27.28. are formed respectively, and a ring groove 2 is formed between the lands ao and aa.
Lands 31 and 32 are formed to face 7 and 28, respectively.

Of course, between those lands 30, 31, 32, and 33,
Spool grooves 71, 72, 73 are formed which can be connected to the power cylinder ports 22, 23, 24, respectively.

Sarani, the control pulp stool 29 is located inside both ends of the Sonocontrol Pulp Stool 29.
A bore 34.35 is formed which extends along the axial direction of the bore 34.35 and is open at both ends.
is connected to the spool groove 71. through the communication hole 40.41.
72, respectively.

The SonoControl Pulp 13 (7) pulp casing 18 is provided with spool guides 36,37 that fit into the bores 34,35 of the SonoControl Pulp spool 29, respectively.

Of course, the stool guides 36 and 37 are assembled with the control pulp stool 29 in consideration of the nature of the installation.
It is preferable that the plug be formed separately from the pulp casing 18 and configured as a plug type that is screwed into the pulp casing 18.

Therefore, the stool guide 36.37 is
4.35 and its control pulp stool 297>Ltd Pulg Casing 18
If the stool chamber 19 is reciprocally slidably disposed in the stool chamber 19, the reaction chambers 38, 3 are co-operated with the end faces of the stool guides 36, 37 and in the bores 34, 35 thereof.
9 are formed respectively.

It goes without saying that the reaction force chambers 38, 39 are connected to the spool grooves 71, 72 through the above-mentioned communication holes 40, 41, respectively.

Further, with the control pulp spool 29 disposed within the spool chamber 19 of the pulp casing 18 as described above, a pair of auxiliary counters are provided on each side of the control pulp spool 29. Force chambers 42, 43 are each formed.

That is, the pair of auxiliary reaction chambers 42, 43 are connected to the reaction chambers 38, 3 by their spool guides 36, 37.
The spool guides 36 and 37 are each formed into a ring shape so as to cover the base side of the spool guides 36 and 37.

Of course, one end of the shaft 66 is fixed at approximately the center of the control pulp spool 29, which slides back and forth in response to steering operation. 6
The other end of 6 is its control pulp casing 1
8 f: Through-hole L-e'-steering shaft (
(not shown) side.

The power cylinder 14 is formed integrally with the casing 20 of the control valve 13 and is connected to the power cylinder port 22, 23, 24 of the control valve 13 (7). A blower cylinder casing comprising a bore 57 and a pair of cylinder chambers 59,60 correspondingly connected to the blower cylinder ports 22,23 and 24 formed within the cylinder bore 57. A power piston 5 is reciprocally slidably disposed within its cylinder bore 57 so as to
To conceptually explain the output section, one end is connected to the power piston 58, and the other end is a bushing extending outwardly through the power cylinder casing. rod 61 and its bushing rod 61 at a position opposite the bushing rod 61.
and a rod 62 fixed substantially coaxially to the ie quake cylinder casing.

Of course: The i9 war cylinder ports 22, 23 of the control pulp 13 of tL'c are connected to its cylinder chamber 59 via the communication passages 63, 64, and... and the war cylinder ports 24 are connected to the communication passages 65 to the cylinder chamber 60, respectively.

The other end of the rod 61 of the power cylinder 14 configured in this way is attached to the chassis frame side of the cab-over type truck, and is located on the opposite side of the bushing 10. The rod 62 is attached to a drag link (not shown) that drives a steering arm (not shown).

In the above description, a linkage type is described, but it goes without saying that an integral type can also be constructed in accordance with the above-mentioned configuration.

The ridge 44 is a fixed throttle, and the above-mentioned flow control pulp 12 (7) control valve port) 16 and control valve y' 13 no pressure jE hoard 2
0.

Of course, the throttle 44 can be provided at any position as long as it is between the control pulp port 16 and the pressure port 20. Set up or
Further, it is also possible to provide the control pulp port 16 in a hydraulic pipe connecting the pressure port 20 with the control pulp port 16.

The auxiliary reaction force control passages 45, 46, 47 communicate the upstream side of the throttle 44 with the pair of auxiliary reaction chambers 42 and 43, respectively.

That is, the auxiliary reaction force control passages 45 and 46.

47 supplies the pressure oil on the upstream side of the throttle 44 to the pair of auxiliary reaction force chambers 42 .
43.

Therefore, the auxiliary reaction force control passage 45 has one end connected to the upstream side of the throttle valve 44 and the other end connected to the pressure port 50 of the auxiliary reaction force control valve 48. 46, 47 have one end connected to the control port 51, 52 of the auxiliary reaction force control valve 48, and the other end connected to the auxiliary reaction chamber 42, . It is connected to ports 25 and 26 of 43.

The auxiliary reaction force control valve 48 is a spool-type directional control valve, and has a pressure port 50 and a pair of control ports 51, 52, and a spool chamber connected to the ports 50, 51, 52 inside. 49, its pressure port 50 is connected to its control port 51,
The spool 53 is slidably disposed in the spool chamber 49 thereof so as to be connected to the spool 52 in a reciprocating manner.

Of course, the spool 53 is slid back and forth by the actuator 55 via the operating rod 54. The actuator 55 may have any form as long as it slides the spool 53 back and forth in response to an electric signal.
Here, an electromagnetic coil is used.

The auxiliary reaction force control valve 48 configured in this manner slides its spool 53 in accordance with the vehicle speed, steering speed, and yaw angular velocity of the cab-over type truck, and controls the auxiliary reaction force chamber 42, 43. It is controlled by a controller 56 to adjust the amount of pressure oil sent to.

That is, the controller 56 controls the steering amount sensor 68
, vehicle speed sensor 69, and yaw angular velocity sensor 70, these sensors 68, 69, 70
It sends an output signal to the actuator 55 in response to an input signal from the auxiliary reaction force chamber 42, 43 to adjust the amount of pressure oil sent to the auxiliary reaction force chamber 42, 43, and mainly includes an input and output circuit, an arithmetic circuit, a memory circuit, and a control circuit.

The steering amount sensor 68 detects the rotation speed, rotation direction, and rotation angle of the steering shaft of the cab-over type truck.
It is arranged so as to cover the outside of the shaft at a predetermined position.

Therefore, the above-mentioned actuator has its controller 5
The steering amount sensor 68 is connected to the output circuit of 6.
is connected to the input circuit of the controller 56.

Of course, it is desirable that the steering amount sensor 68 has a high resolution as a rotation sensor, consumes little power, and generates a reliable and large signal as an output. Semiconductor types are used.

The vehicle speed sensor 69 detects the rotation speed of the output shaft of the transmission in the cab-o-gu type truck.
The above-mentioned controller 5 is arranged behind the transmission.
6 input circuit.

Of course, it is preferable to use a non-contact type vehicle speed sensor 69 in consideration of the limitation of the usable rotational speed of the converter bearing and the load on the output shaft of the transmission.

The yaw angular velocity sensor 70 detects the yaw angular velocity of the shaft 7 and the rack when it is running, and is configured in a gyro type.
It is attached to the frame side and further connected to the input circuit of the controller 56.

Next, to describe the driving of a cab-over type truck to which the above-mentioned power steering is applied, the controller 56 constantly inputs signals from the steering amount sensor 68, the vehicle speed sensor 69, and the yaw angular velocity sensor 70, and outputs the A signal is sent to the actuator 55 of the auxiliary reaction force control valve 48.

That is, in order to turn the cab-over type truck, when the steering wheel is rotated, the control valve 13 (7) and the control valve spool 29 slide, while the controller 56 rotates the steering wheel. The rotation, that is, the signal from the steering amount sensor 68 is input, and an output signal is sent to the actuator 55 to control the auxiliary reaction force control valve 48.

For example, by rotating the steering wheel clockwise, if the control valve spool 29 slides to the right in the diagram, the pressure port 20
is connected to the power cylinder port 24 by the spool groove 72 of the control pulp spool 29, and the pressure oil sent from the oil pump 7'll via the flow control pulp 12 is connected to the power cylinder 14. The /P quake cylinder 14 is operated.

Of course, a part of the pressure oil sent to the pressure port 20 is sent to the reaction force chamber 39 via the communication hole 39.

That is, the reaction force due to steering as described above is given by the pressure within the reaction force chamber 39.

Further, when the steering wheel is rotated clockwise in this manner, the controller 56 detects the steering amount sensor 68.
input the signal from the actuator 55, and further input the signal from the actuator 55
send the output signal to.

As a result of the output signal being sent to the actuator 55, the spool 53 of the auxiliary reaction force control valve 48 slides, and the pressure oil on the upstream side of the throttle 44 is sent to either one of the auxiliary reaction force chambers 42, 43. However, the selection of either one of the auxiliary reaction force chambers 42 or 43 and the amount of pressure oil are determined by the steering amount sensor 68, vehicle speed sensor 69, and yaw angular velocity sensor 70.
In other words, the signal is determined according to the rotation speed, rotation direction, rotation angle, vehicle speed, and yaw angular velocity of the steering/yaft.

That is, when the steering wheel is rotated clockwise, the controller 56 controls the steering amount sensor 6.
Input the signal from actuator 8, and further input the signal from actuator 5.
By sending an output signal to 5, the auxiliary reaction force control valve 4
8 spool 53 is slid to the left in the figure.

If the spool 53 is so slid, the pressure port 50 of the auxiliary reaction force control valve 48 becomes the control port 52.
Pressure oil is sent to the upstream side of the throttle shaft 44 through the oil pump 11 color flow control pulp 12tJI, and is sent to the auxiliary reaction chamber 42 via the auxiliary reaction force control passages 45 and 46. It will be done.

Therefore, the pressure oil sent to the auxiliary reaction chamber 42 causes the control valve spool 29 to slide to the right in the figure.

Of course, the amount by which the control valve spool 29 slides is the amount of pressure oil sent to the auxiliary reaction force chamber 42, in other words, the amount by which the control valve spool 29 slides is determined by the amount of pressure oil sent to the auxiliary reaction chamber 42. It is determined in response to a signal from 70.

That is, by rotating the steering wheel in almost the same way as the existing Nokwer Steering, the control valve spool 29 is reciprocated and /? The mulch cylinder 14 is operated, but there is a delay in its control pulp spool 29, and the amount of sliding of the control pulp spool 29 relative to the rotation of the steering wheel is small, and the actual Even when the steering angle is small, the sliding movement of the control pulp spool 29 is corrected by the pressure oil sent to the auxiliary reaction force chamber 42, thereby preventing delays in the operation of the control valve spool 29. .

Of course, the above-mentioned operation of the main power steering 10 is explained using the case where the operation delay of the control pulp spool 29 is reduced in accordance with the signal from the steering amount sensor 68, but the power steering wheel 1
0, the controller 56 inputs signals from not only the steering amount sensor 68 but also the vehicle speed sensor 69 and the yaw angular velocity sensor 70, and sends an output signal to the actuator 55 of the auxiliary reaction force control valve 48. sending.

As a result, for example, when the cab-over type truck is traveling at high speed and the yaw angular velocity increases due to sudden operation of the steering wheel, the steering amount sensor 68, vehicle speed sensor 69, and yaw angular velocity sensor 70
The controller 56 inputs a signal from the
The controller 56 sends an output signal to the actuator 55, sends a pressure ft1 to either of the auxiliary reaction force chambers 42, 43, and directs the -t- control valve spool 29 in a direction that maintains running stability. Correct to.

That is, if such a sudden operation of the steering wheel causes its control bar/l/17' stool 29 to slide to the right in the figure, the signals from those sensors 68, 69, 70 In response, the controller 56 sends an output signal to the actuator 55, causing the stool 53 of the auxiliary reaction force control valve 48 to slide to the right in the figure.

When the stool 53 is slid in this manner, pressure oil on the upstream side of the throttle 44 is sent into the auxiliary reaction force chamber 43.

Therefore, the pressure oil in the auxiliary reaction chamber 43 causes the control pulp spool 29t to slide to the left.

In other words, even if the steering wheel is suddenly operated while driving at high speed, the pressure oil sent into the auxiliary reaction chamber 43 will cause the control pulp stool 2 to
9 sliding is corrected and the cab-over type truck is prevented from being placed over or under the steering,
Furthermore, generation of spin is prevented.

According to this invention of the above, oil? A control pulp with a reaction chamber on each side of the control pulp stool, and a pair of auxiliary reaction chambers separated from the reaction chamber on the other side of the power cylinder. are formed on each side of the control pulp stool, and a restriction is provided between the flow control pulp and the control pulp pressure port of the control pulp. Further, an auxiliary reaction force control passage communicates the upstream side of the throttle with each of the pair of auxiliary reaction chambers, and an auxiliary reaction force control valve is provided in the auxiliary reaction force control passage, and the auxiliary reaction force control valve is provided in the auxiliary reaction force control passage to adjust the vehicle speed and steering speed. , and adjusts the amount of pressure oil sent to its pair of auxiliary reaction chambers according to the yaw angular velocity, and its control pulp stool slides hydraulically rather than mechanically. let me,
Its control pulp stool is configured to properly compensate for its movement, so that it always
The control pulp stool should be properly reciprocated to prevent slowing of the control pulp spool, in other words, the sensitivity of the control pulp stool should be constant. This makes it easier to steer while obtaining appropriate reaction force, and also provides excellent maneuverability when applied to vehicles where economy is prioritized, such as loading efficiency and cabin space. It provides stability and allows safe driving through easy steering operation, making it extremely practical.

[Brief explanation of the drawing]

The figure is a schematic diagram showing a specific example of the power steering system used in the vehicle of the present invention applied to a cab-over type truck. lO...Power steering used in vehicles, 1
1... Oil pump 7', 12... Flow control pulp, 13... Control pulp, 1
4...No1r) - Cylinder, 20... Pressure port, 29... Control pulp stool, 38,
39...Reaction force chamber, 42.43...Auxiliary reaction force chamber, 44
... Throttle, 45.46.47... Auxiliary reaction force control passage, 48... Auxiliary reaction force control valve, 68... Steering amount sensor, 69... Vehicle speed sensor, 70... Yaw Angular velocity sensor.

Claims (1)

[Claims] Oil pump, flow control pulp, control: control pulp, each having a reaction chamber on both sides of the pulp spool, and a power cylinder for steering, comprising: Auxiliary reaction force chambers are separated from the reaction force chamber and formed on both sides of the control pulp spool of Teso, and the control pulp spool of the flow control pulp is squeezed. :I Troll・
Further, an auxiliary reaction force control passage communicates the upstream side of the throttle with the pair of auxiliary reaction chambers, and an auxiliary reaction force control valve is provided between the auxiliary reaction force chamber and the pulp pressure port. Provided in the force control passage to control vehicle speed, steering speed,
and a power steering system used in a vehicle, which adjusts the amount of pressurized oil sent to the pair of auxiliary reaction chambers according to the yaw angular velocity.