JPH0143670B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a power steering valve system, and particularly to a rotary type valve system.

Since this type of rotary type operating valve device can simplify the configuration of the power steering operating system, it is useful as an operating valve device for power steering whose mission is to be compact, and there is a tendency for it to be used more frequently. This type of actuated valve device usually includes an inner and outer sleeve that are fitted together in sliding contact with each other;
One sleeve is drive-coupled to the steering wheel, and the other sleeve is drive-coupled to the input gear element of the steering gear. Both sleeves are connected by a torsion bar, and the inner and outer sleeves are rotated relative to each other by twisting the torsion bar in response to the steering load. At the very least, an assist hydraulic pressure corresponding to this relative rotation amount (steering load) is generated, and the hydraulic pressure assists the steering in the steering direction during steering, thereby enabling light power steering.

By the way, if there is only one means for drivingly coupling the other sleeve to the input gear element of the steering gear, if this means is damaged, the rotational position of the sleeve will not be determined and the above-mentioned assist hydraulic pressure may be generated. As the steering power decreases, the steering force suddenly becomes heavier.
In the worst case scenario, the vehicle may become unable to steer, which is extremely dangerous. Therefore, conventionally, two of the above methods were used in one
An operating valve device has been proposed that is provided as a set and has a double safety measure so that even if one means is damaged, power steering can be continued by the other means. However, in the conventional countermeasures, both of the above-mentioned means have tightly drivingly engaged the other sleeve with the input gear element. However, it is not until the other means breaks down while the vehicle is traveling in this state that it becomes aware of the malfunction of the operating valve device. However, it is already too late to do so and the above-mentioned danger cannot be avoided.

According to the present invention, when one of the means is damaged, if the driver can intuitively know this condition and repair it immediately, the dual safety measures can be kept effective at all times. From the viewpoint of reliably preventing major accidents, the present invention attempts to provide a power steering valve device that embodies this idea.

Hereinafter, the present invention will be explained in detail with reference to illustrated embodiments.

1 to 5 show embodiments in which the actuated valve device of the present invention is configured to be used in a rack-and-pin-on type steering gear, but the device of the present invention is not limited to this type of steering gear. It can be used for any other type of steering gear.

In the figure, 1 is a valve box, and a handle guide 2 is integrally provided at one end of the valve box, and an opening at the other end is closed with an end cover 3. A rack 4 is inserted into the rack guide 2 to guide the rack 4 so as to be movable in its longitudinal direction, and a steering gear is constituted by the rack 4 and a pinion 11a that meshes with the rack teeth 4a as described below.
In this case, the pinion 11a becomes the input gear element of the steering gear. Although not shown, knuckle arms provided on the corresponding steering wheels are connected to both ends of the rack 4, and both steering wheels are steered in the steering direction by longitudinal movement of the rack 4 as the pinion 11a rotates. possible. The rack 4 is provided with a power piston 5 as shown in FIG.
8, and connectors 9 and 10 are connected to these chambers, respectively. When hydraulic pressure is supplied to the left chamber 7 of the power cylinder chambers 7 and 8, the rack 4 is power assisted to the right in FIG. When hydraulic pressure is supplied to the rack 4, the rack 4 is power assisted to the left in FIG. 3, and can assist in steering both steered wheels to the right.

As shown in FIGS. 1 and 3, the rack teeth 4a
, the pinion 11 provided on the pinion shaft 11
a, and pinion shaft 11 is engaged with bearing 1.
2 and 13, the axial position is fixed and rotatably supported. The side of the rack 4 opposite to the pinion 11a is supported by a column 14 as shown in FIG. give. A stub shaft 17 is disposed coaxially with the end of the pinion shaft 11 protruding within the valve box 1 under liquid-tight sealing by a seal 16, and the opposing ends of both shafts are made relatively rotatable by bearings 18. The other end of the stub shaft 17 is supported by the end cap 3 via a bearing 19 and is penetrated through the end cap 3 under liquid-tight sealing by a seal 20. Incidentally, a serration 17a is formed at the end of the stub shaft 17 that penetrates the end cover 3 and projects from the valve box 1, and a steering wheel (not shown) and a steering shaft that can be rotated integrally can be connected via this serration. do.

The stub shaft 17 is made hollow, and the torsion bar 21 is inserted into the hollow hole.
One end of the pinion shaft 11 is fitted into a blind hole 11b formed in the end face of the pinion shaft 11 and is bolted to the pinion shaft 11 with a pin 22, and the other end is connected to the pinion shaft 11 with a pin 22.
3, it is bolted to the stub shaft 17. Thus, the stub shaft 17 is coupled to the pinion shaft 11 via the torsion bar 21 and its axial position is fixed.

An inner sleeve 24 is integrally molded on the stub shaft 17, and this inner sleeve is disposed within the valve body 1. The outer sleeve 27 is slidably fitted to the outer circumferential surface of the inner sleeve 24 so as to be relatively rotatable, and the outer circumferential surface of the outer sleeve 27 is slidably fitted to the inner circumferential surface of the valve box 1. The outer sleeve 27 is sandwiched between the protrusion 24e provided on the inner sleeve 24 and the bearing 19.
4 is determined, and the axial position is fixed by bringing both end surfaces 25 and 26 of the outer sleeve 27 into contact with the bottom surface 1a of the valve box 1 and the bearing 19, respectively. As shown in FIG. 2, the inner peripheral surface of the outer sleeve 27 has, for example, four circular recesses 27a, 27b, spaced apart from each other at equal intervals in the circumferential direction.
27 c and 27 d to define spaces 28 , 29 , 30 , and 31 between the inner sleeve 24 and the outer circumferential surface of the outer sleeve 27 .
Form e, 27f, and 27g.

As clearly shown in FIG. 2, grooves 24a, 24b, 24c, and 24d are formed on the outer peripheral surface of the inner sleeve 24 to communicate adjacent spaces 28 to 31.
The grooves 24b and 24c have a concave bottom surface as shown in FIG.
It should be approximately equal to the opening edge circle diameter of d.

The outer sleeve 27 is further provided with holes 33 to 36 passing through it in the radial direction, and these holes are connected to the outer sleeve 27.
Grooves 24a, 24c, 24 on the inner circumferential surface of
The holes 33 and 24d are opened at positions opposite to the holes 33,
The opening at the other end of 34 is common to the groove 27g, and is also open to the hole 3.
The other end openings 5 and 36 are commonly communicated with the groove 29f as shown in FIG. The outer sleeve 27 also has
Holes 37 and 38 are drilled, and the space 2 is filled with these holes.
8 and 29 are connected to the grooves 27e, respectively, and the depressions 3
0 and 31 are diagonal holes 5 bored in the outer sleeve 27, respectively.
0 (only the diagonal hole for the recess 30 is shown in FIG. 1) opens into a drain chamber 39 defined between the end cap 3 and the outer sleeve 27.

As clearly shown in FIGS. 4 and 5, the pinion shaft 11 is integrally provided with a pair of protrusions 11c that protrude radially outward at an end close to the inner sleeve 24, and these protrusions are connected to the fan-shaped cutout of the inner sleeve 24. Notch 2
4f, and a pair of pins 40 and 47 are implanted on the outer peripheral surface of the projection 11c. Fan-shaped cutout 2
4f is slightly larger than the width of the protrusion 11c so that these protrusions, and hence the pinion shaft 11, are within an allowable range for the inner sleeve 24, that is, within the range until the side surface of the protrusion 11c collides with the wall of the fan-shaped notch 24f. Allows relative rotation. Further, the pins 40 and 47 are inserted into notch grooves 25h and 25i formed by opening in the end surface 25 and inner peripheral surface of the outer sleeve 27, respectively, and the width of these notch grooves 25h and 25i is set to a fourth width.
Make it the same as shown in the figure. However, the pins 40 and 47 have different diameters, and the diameter of the pin 40 is made the same as the width of the notch groove 25h so that it tightly engages with the notch groove 25h in the rotational direction as shown in FIG.
The diameter is made slightly smaller than the width of the notch groove 25i so that it engages with the notch groove 25i with a slight gap in the rotational direction as shown in FIG. Thus, the outer sleeve 27 is drivingly engaged with the pinion shaft 11 having the pinion 11a, which is an input gear element of the steering gear, through the pin 40 and the notched groove 25h, and can rotate integrally with the pinion 11a.

The valve box 1 has an inlent port 41 opening into the groove 27e as shown in FIG. 1, a drain port 42 communicating with the drain chamber 39, and a drain port 42 communicating with the grooves 27f and 27g as shown in FIG. Communication port 43,4
4. The inlet port 41 is connected to an oil pump (not shown), the drain port 42 is connected to an oil reservoir, and communication ports 43 and 4 are connected to each other.
4 are connected to power cylinder chambers 7 and 8 via conduits 45 and 46 and connectors 9 and 10, respectively.

The operation of the operating valve device of the present invention having the above-mentioned structure will be explained next.

1 to 5 show the state when the steering wheel is stopped rotating and the operating valve device of the present invention is in a neutral state. In this state, as is clear from FIG.
Both ends of the inlet port 4 are equally open to the corresponding cavities 28 to 31, and the inlet port 4 is connected from the oil pump to the inlet port 4.
1. Hole 2 via groove 27e and through holes 37 and 38
The hydraulic oil supplied to the holes 7 and 28 is extracted through the grooves and spaces 30 and 31, as well as the diagonal hole 50, the drain chamber 39, and the drain port 42, and is drained to the spaces 28,
29 does not generate oil pressure. At the same time, the power cylinder chambers 7 and 8 shown in FIG.
3, 34, 35, 36, grooves 24a, 24b, 24
c, 24d lead to drainage cavities 30, 31, allowing the rack 4 to move freely in its longitudinal direction.

Here, when the steering wheel is rotated to perform a steering operation, the torsion bar 21 is not twisted and the stub shaft 11 is rotated via this torsion bar when the steering load is small. Directional movement turns the steered wheels without power assistance.

However, when the steering load is large during steering operation, the pinion shaft 11 does not rotate following the stub shaft 17, and the torsion bar 21 is twisted in the steering direction according to the steering load, and as described above, the pinion shaft 11 is rotated through the pin 40. The outer sleeve 27, which rotates integrally with the stub shaft 17, and the inner sleeve 24, which is integral with the stub shaft 17, rotate relative to each other in the steering direction by an angle corresponding to the steering load, and the operating valve device of the present invention performs steering operation by the following action. Performs power assist at time.

That is, when the steering operation is performed to the left, the inner sleeve 24 rotates relative to the outer sleeve 27 in the direction shown by the arrow in FIG. 2 by an angle corresponding to the steering load.
At this time, the degree of communication of the grooves 24a, 24b, 24c, and 24d with the spaces 28, 30, 29, and 31 on the lagging side of the rotational direction of the inner sleeve 24 is reduced, and the communication with the spaces 28, 30, 29, and 31 on the leading side of the rotational direction of the inner sleeve 24 is reduced. Increase the degree of communication with 30, 29, 31, and 28. As a result, assist hydraulic pressure is generated in the spaces 28 and 29, and as described above, the right power cylinder chamber 8 (the third
The holes 33, 34 which communicate with the drain holes 30, 31 (see figure) communicate largely with the drain cavities 30, 31. Blank space 28, 29
The assist hydraulic pressure generated inside is supplied to the power cylinder chamber 7 on the left side through the grooves 24d and 24b, the holes 36 and 35, the groove 27f, the communication port 43, and the conduit 45, and moves the rack 4 toward the right in FIG. Power assists to help steer the steering wheels to the left.

Further, when the steering operation is performed to the right, the inner sleeve 24 is rotated in the opposite direction to the above-described direction relative to the outer sleeve 27, and at this time, assist hydraulic pressure is similarly generated in the spaces 28 and 29. However, in this case, the assist hydraulic pressure in the spaces 28 and 29 is
c, is supplied to the power cylinder chamber 8 on the right side through holes 33 and 34, and the power cylinder chamber 7 on the left side is supplied to the hole 3
5 and 36 to the drain spaces 30 and 31, the rack 4 is power-assisted to the left in FIG. 3, and power steering is possible when steering to the right.

If the hydraulic oil flow to the inlet port 41 is lost due to a failure of the oil pump or its drive system, and the above-mentioned power steering becomes impossible, the torsion bar 21 is greatly twisted due to the lack of power assist force, and the fourth The wall of the fan-shaped notch 24f shown in the figure and the side surface of the projection 11c collide. Therefore, the steering (rotation) force input to the inner sleeve 24, which is integrated with the stub shaft 17, is mechanically transmitted to the pinion shaft 11 via the protrusion 11c, and when the power steering malfunctions, steering can be performed by manual steering. In this case, the risk of becoming unable to steer the vehicle can be prevented.

By the way, in the present invention, in order to drively engage the outer sleeve 27 with the pinion shaft 11, not only the pin 40 and the notch 25h are used, but also the pin 47 and the notch 27i are used to perform the above-mentioned drive engagement. Because of this, when the pin 40 is broken, the drive engagement by the pin 47 becomes effective,
In this case as well, the outer sleeve 27 and pinion shaft 1
1 is maintained, providing a dual safety feature that prevents said power steering from becoming impossible.
In this case, the direct diameter of the pin 47 is the notch groove 2.
outer sleeve 2 with a width smaller than 5i;
7 and the pinion shaft 11 is performed with some play in the rotational direction, there is a delay in response to power steering, and the play is transmitted to the steering wheel, making the driver feel uncomfortable. Breakage of the pin 40, which is the main driving engagement element, can be immediately detected.

As described above, the operating valve device of the present invention has two inner and outer sleeves.
4 and 27, one sleeve (outer sleeve 27 in the illustrated example) to be drivingly engaged with the input gear element (pinion shaft 11 in the illustrated example) of the steering gear and the input gear element are connected in a one-to-one pair (the illustrated example is the pinion shaft 11). In the example shown, pins 40, 47 and notched grooves 25h, 25
i), one means (pin 40 and notched groove 25h in the illustrated example) is adapted to bring the one sleeve into tight driving engagement with the input gear element, and the other means (in the illustrated example In this case, since the pin 47 and the notched groove 25i) are configured to drive and engage the one sleeve with the input gear element with some play, even if one of the means is damaged, the other means will not be damaged. A double safety function is achieved that is effective and prevents power steering from suddenly becoming impossible, and the driver can quickly and intuitively know this condition due to the above-mentioned backlash. Therefore, by learning of the malfunction and immediately repairing it, the driver can keep the above-mentioned double safety measures in effect at all times, and can reliably prevent a major accident.

[Brief explanation of drawings]

Figure 1 shows the operating valve device of the present invention at A ₁ -O in Figure 2.
-A ₂ -A ₃ -A ₄ A cross-sectional view taken along the line and viewed in the direction of the arrow, Figure 2 is a cross-sectional view of B ₁ - B ₂ in Figure 1, Figure 3 is a cross-sectional view of C ₁ - A in Figure 2 ₂ -C ₂ -O-C ₃ -C ₄ -C ₅ A sectional view taken in the direction of the arrow, Fig. 4 is a sectional view of D ₁ - D 2 of Fig. 1, Fig. 5 is a sectional view of D 1 - D ₂ of Fig. It is a partial sectional view taken along the line _E1 - _E2 in the figure and viewed in the direction of the arrow. 1... Valve box, 2... Rack guide, 3... End cover, 4... Rack, 4a... Rack tooth, 5... Power piston, 6... Power cylinder, 7, 8...
...Power cylinder chamber, 11...Pinion shaft, 11a...Pinion (input gear element), 17
...Stubshaft, 21 ...Torsion bar,
22, 23...Pin, 24...Inner sleeve, 25
h, 25i...notch groove, 27...outer sleeve,
28-31... Blank space, 24a, 24b, 24c,
24d...Groove, 27a, 27b, 27c, 27d
...Circular recess, 27e, 27f, 27g...Groove, 33-38...Hole, 39...Drain chamber, 4
0,47...pin, 41...inlet port,
42...Drain port, 43, 44...Connection port, 45, 46...Pipe line, 50...Diagonal hole.

Claims (1)

[Claims] 1. An inner sleeve and an outer sleeve are fitted to each other so as to rotate relative to each other in response to a steering load and generate an assist hydraulic pressure corresponding to the amount of relative rotation, and one of these sleeves is driven by a steering wheel. In a power steering operating valve device in which the other sleeve is coupled to the input gear element of the steering gear and the other sleeve is drivingly engaged with the input gear element of the steering gear, means for drivingly engaging the other sleeve with the input gear element of the steering gear are provided as a one-to-one pair; The means is configured to bring the other sleeve into tight driving engagement with the input gear element, and the other means is configured to bring the other sleeve into driving engagement with the input gear element with some play. Features a power steering valve device. 2. Both of the means are each composed of a pin and a notched groove into which the pin penetrates, and the diameter of the pin and the width of the notched groove are determined so that the pin of the one means densely penetrates into the corresponding notched groove, The operating valve device for power steering according to claim 1, wherein the diameter of the pin and the width of the notch groove are determined so that the pin of the other means penetrates the corresponding notch groove with play. .