JP2000199574A - Check valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a low-cost check valve stable in operation, excellent in assembly workability, and decreased in the number of parts. SOLUTION: A cylinder case 1 is provided at one end with a plurality of hydraulic passages 3 and a through-hole 4 pointing to the inside and a protrusion part 5 having a plane part 4 formed on an upper part and an opening part 7 capable of being caulked and formed in the other end. A poppet valve 8 comprises a rod-form part 9 inserted in the through-hole 4; and a spherical crown-form part 10 attached to the end part of the rod-form part 9 and seating the plane part 6 during ordinary operation and closing the opening part 7 during a reverse flow of an oil pressure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a check valve used in a power steering device of an automobile for transmitting the rotation of a steering wheel to a steering wheel.

[0002]

2. Description of the Related Art A conventional power steering apparatus using a check valve is shown in FIG.

[0005] In FIG. 5, reference numeral 101 denotes a control valve.
From 02, hydraulic oil is introduced into the power cylinder 103. The inside of the valve body 104 of the control valve 101 is formed to be hollow, and a torsion bar 105 is inserted into the inside of the valve body 104 and fixed with a pin 106. A plurality of grooves 107, 108, 109 are formed on the outer periphery of the valve body 104, and the operating oil from the pump 102 is supplied to one side of the power cylinder 103 by operating the handle in one direction through these grooves 107, 108, 109. The hydraulic oil from the other cylinder 111 returns to the reservoir tank 112 while the hydraulic oil from the pump 102 is moved to the other cylinder chamber 111 of the power cylinder 103 by operating the handle in the other direction. At the same time, the hydraulic oil in one of the cylinder chambers 110 returns to the reservoir tank 112.

The valve body 104 is housed in a cylinder 113 so as to be movable up and down by operating a handle.
The space between the valve body 3 and the valve body 104 is sealed by an oil seal 114 so that hydraulic oil does not leak to the outside. Cylinder 1
13 is fixed to the gear housing 116 by bolts 115.

[0005] An outer cylinder 117 is attached to the outer periphery of the cylinder 113, and the outer cylinder 117 has four ports 118, 11.
9, 120 and 121 are respectively formed.

A port 118 is a pressure port provided for introducing hydraulic oil from a pump via an introduction oil passage. The port 118 has grooves 107, 108, and 10.
9 is provided with a check valve 122 that can communicate with the check valve 9.

A port 119 for returning hydraulic oil to the reservoir tank 112 is provided above the port 118, and the port 119 communicates with the reservoir tank 112 via a discharge oil passage 123. The port 120 is an input / output port for introducing hydraulic oil into one of the cylinder chambers 110 of the power cylinder 103 and for returning the hydraulic oil in the cylinder chamber 110 to the power cylinder 113 via the input / output oil passage 124. Is communicated with one of the cylinder chambers 110.

A port 121 provided above the port 120 returns hydraulic oil in the other cylinder chamber 111 of the power cylinder 103 to the reservoir tank 112 and introduces hydraulic oil into the other cylinder chamber 111 of the power cylinder 103. I / O port for
25 communicates with the other cylinder chamber 111 of the power cylinder 103.

A rack shaft 126 is housed in the power cylinder 103 so as to be movable in the left-right direction. A large-diameter portion 127 of the rack shaft 126 divides the cylinder chamber 128 into one cylinder chamber 110 and the other cylinder chamber 111. are doing.
When hydraulic oil is inserted into one cylinder chamber 110 and hydraulic oil is discharged from the other cylinder chamber 111, the rack shaft 1
26 moves leftward in the figure, and when hydraulic oil is introduced into the other cylinder chamber 111 and hydraulic oil is discharged from one cylinder chamber 110, the rack shaft 126 moves rightward in the figure.

When the handle is operated in one direction, for example, in the right direction, the control valve 101 moves downward in the cylinder 113, and hydraulic oil from the pump 102 enters a port 118 as a pressure port through an introduction oil passage 129. Through the check valve 122, the port 120, the input / output oil passage 12
4 to one cylinder chamber 110 of the power cylinder 103
to go into. On the other hand, the hydraulic oil in the other cylinder chamber 111 of the power cylinder 103 is supplied with an input / output oil passage 125, a port 121,
119 to the reservoir tank 112 from the discharge oil passage 123
Return to Thus, the rack shaft 126 connected to the steering wheel (not shown) moves to the left.

When the handle is operated in the other direction, for example, to the left, the control valve 101 moves upward in the cylinder 113, and the operating oil from the pump 102 is supplied to the introduction oil passage 129, the port 118 as a pressure port, the check valve 1
Through the port 22, the fluid is introduced into the other cylinder chamber 111 of the power cylinder 103 through the port 121 and the input / output oil passage 125. On the other hand, the hydraulic oil in the other cylinder chamber 110 of the power cylinder 103 is supplied to the input / output oil passage 124, the port 12
0, and returns from the discharge oil passage 123 to the reservoir tank 112 via the port 119. Thus, the rack shaft 126 connected to the steering wheel (not shown) moves rightward.

The steering force is assisted by these actions. However, when the vehicle is traveling on an uneven road surface or the like, hydraulic oil due to reverse input (so-called kickback) from the steered wheels flows backward, so that the power cylinder 103 operates and so-called steering wheel is generated.

In order to solve this problem, in a conventional power steering apparatus, a port 11 as a pressure port is used.
By providing a check valve 122 in 8, the backflow of hydraulic oil when kickback is input is prevented, so that the handle cannot be removed.

FIG. 6 shows a conventional check valve 122.

In FIG. 6, reference numeral 130 denotes a cylindrical case, and three claw portions 131 are respectively formed on the bottom of the cylindrical case 130, and the tips of the claw portions 131 are bent inward. Hydraulic passages 132 through which hydraulic oil passes are formed at the bottom by the claws 131. An opening formed by caulking is formed at the upper part of the cylindrical case 130, and a groove 133 is formed inside.

The outer peripheral end of the valve seat 134 is fitted into the groove 133, and the valve seat 134 is fixed by caulking to the opening of the cylindrical case 130. The valve seat 134 has an opening 135 into which hydraulic oil is introduced.
Reference numeral 136 denotes a poppet valve provided inside the valve seat 134. An orifice hole 137 in the center of the poppet valve 136 allows a part of hydraulic oil to flow backward.
Are formed. Protrusions 138 protruding downward are formed at three locations inside the poppet valve 136, respectively.

A circumferential recess 139 is formed inside the poppet valve 136 and outside the orifice hole 137, and a spring 140 is interposed between the recess 139 and the bottom of the cylindrical case 130. I have. The poppet valve 136 is provided with a valve seat 134 by a spring hole 140.
It is provided so that it may contact inside.

In operation, hydraulic oil from the pump passes through the opening 135 of the valve seat 134 and passes through the poppet valve 1.
36 is pressed down against the spring 140 so that the projection 13
8 and the projection 138, and is introduced into the power cylinder through the hydraulic passage 132 of the cylindrical case 130. Also,
When the hydraulic oil flows back through the hydraulic passage 132,
The poppet valve 136 is in close contact with the inside of the valve seat 134 and closes the opening 135 of the valve seat 134 to prevent backflow. In this case, the orifice hole 137 of the poppet valve 136 allows a part of the hydraulic oil to flow backward.

In this way, the backflow of hydraulic oil due to kickback is prevented, so that the handle cannot be removed.

[0020]

However, in such a conventional check valve, the poppet valve is formed in a substantially umbrella shape, has a complicated shape, is unstable in operation, and is assembled. Also, the assembly workability was poor because of using a spring. Further, a spring is required, and the number of parts increases. As a result, there is a problem that the cost increases.

The present invention has been made in view of such conventional problems, and has a simple poppet valve, stable operation, good assembly workability, and a reduced number of parts. It is an object to provide a low-cost, low-cost check valve.

[0022]

In order to achieve this object, the present invention is configured as follows.

According to the first aspect of the present invention, the control valve is operated by the handle to introduce the hydraulic oil from the pump into one cylinder chamber of the power cylinder and return the hydraulic oil from the other cylinder chamber to the reservoir tank so that the rack shaft is moved. In a check valve used for a moving power steering device, a plurality of hydraulic passages are provided at one end, a through-hole is provided on the one end, and a projection having a flat portion is provided at an upper portion. A cylindrical case, a rod-shaped portion inserted into the through hole, and a spherical cap attached to an end of the rod-shaped portion, which is seated on a flat portion during normal operation and closes the opening portion when hydraulic pressure flows backward. A poppet valve.

According to a second aspect of the present invention, the control valve is operated by the handle to introduce the hydraulic oil from the pump into one cylinder chamber of the power cylinder and return the hydraulic oil from the other cylinder chamber to the reservoir tank to move the rack shaft. In a check valve used in a power steering device to be moved, a plurality of hydraulic passages at one end, a projection having an inner through hole and an upper flat portion are provided, and an opening capable of being caulked at the other end. A cylindrical case having a valve seat having a hydraulic passage hole fixed to the opening portion and communicating with the opening portion, a rod portion inserted into the through hole, and attached to an end of the rod portion, and normally operated. A poppet valve having a spherical crown portion which is sometimes seated on a flat surface portion and closes a hydraulic passage hole of the valve seat at the time of hydraulic backflow.

According to a third aspect of the present invention, in the check valve according to the first or second aspect, a cutout which forms an orifice groove when the opening or the hydraulic passage hole is closed is formed in the spherical crown portion of the poppet valve. did.

According to the present invention having such a configuration,
The cylindrical case has a plurality of hydraulic passages at one end, a through-hole for the inside, a projection with a flat portion at the top, and a caulking opening at the other end, and a poppet valve at the through-hole. It has a rod-shaped part to be inserted and a spherical cap that is attached to the end of the rod-shaped part and sits on a flat part during normal operation and closes the opening part when hydraulic pressure reverses, so that the inclination and the left and right movement of the poppet valve are restricted. The operation is stable, the shape of the poppet valve is simple and the assembly workability is good,
Further, the number of parts can be reduced.

As a result, the cost can be significantly reduced.

The same effect as described above can be obtained also when an additional valve seat having a hydraulic passage hole fixed to the opening of the cylindrical case and communicating with the opening is additionally provided.

Further, since a notch serving as an orifice groove is formed in the spherical crown portion of the poppet valve when the opening of the cylindrical case or the hydraulic passage hole of the valve seat is closed, the hydraulic oil can flow back during kickback due to kickback. Partial backflow can be allowed, and the operation of the valve can be further stabilized.

[0030]

FIG. 1 is a sectional view showing a first embodiment of the present invention, and FIG. 2 is a bottom view of FIG.

1 and 2, reference numeral 1 denotes a cylindrical case, and the cylindrical case 1 is formed of, for example, a sheet metal. Three substantially fan-shaped holes are formed in the bottom 2 of the cylindrical case 1 in the circumferential direction, and these holes constitute the hydraulic passage 3.

A through hole 4 is formed at the center of the bottom 2 of the cylindrical case 1.
Is formed, and a protrusion 5 protruding inward around the through hole 4.
Are formed. A flat portion 6 is formed on the upper end of the protrusion 5. The upper end of the cylindrical case 1 opposite to the bottom 2 is
An opening 7 is formed inside by being caulked in a tapered shape. Oil pressure from a pump is introduced into the opening 7.

Reference numeral 8 denotes a poppet valve. The poppet valve 8 includes an elongated rod-shaped portion 9 and a spherical crown portion 10 attached to an end of the rod-shaped portion 9. The rod-shaped portion 9 is slidably housed in the through hole 4 of the cylindrical case 1, and the crown-shaped portion 10 is seated on the flat portion 6 of the projection 5 during normal operation without hydraulic backflow due to kickback. When the hydraulic pressure reversely flows, the opening 7 of the cylindrical case 1 is closed. The poppet valve 8 moves along the through hole 4 in the bottom 2 so that the opening 7 of the cylindrical case 1 can be reliably opened and closed. Due to the above-described structure, the inclination and the left and right movement of the poppet valve are regulated.

As shown in FIG. 3, a notch 11 is formed at the shoulder of the spherical crown 10 of the poppet valve 8, and the poppet valve 8 is seated in the opening 7 of the cylindrical case 1 and Is closed, the notch 11 forms an orifice hole that allows a part of the hydraulic oil to flow backward.

At the time of normal operation in which hydraulic pressure flows, the rod-shaped portion 9 of the poppet valve 8 is inserted into the through hole 4 of the projection 5 and the spherical crown-shaped portion 10 is The seat 7 is seated on the flat part 6 and the opening 7 of the cylindrical case 1 is open. The poppet valve 8 is slidably inserted into the through hole 4, and the inclination and the left and right movement of the poppet valve 8 are restricted.

In this state, the hydraulic oil from the pump passes through the opening 7 of the cylindrical case 1, passes between the inner wall of the cylindrical case 1 and the poppet valve 8, and passes through the hydraulic passage 2 of the cylindrical case 1. Supplied to the power cylinder. In this way, the rack shaft connected to the steered wheels is moved, and the operating force is assisted.

On the other hand, when traveling on uneven road surfaces,
When the hydraulic oil flows backward due to kickback from the steered wheels, the hydraulic pressure enters through the hydraulic passage 2 of the cylindrical case 1 and presses the poppet valve 8. The poppet valve 8 responds to the flow of the hydraulic pressure at the time of kickback, and
1 and moves upward in FIG.
And the opening 7 is closed. In this way, the backflow of the hydraulic oil when kickback is input is prevented, and the steering wheel is not taken.

The poppet valve 8 has a simple shape and is easy to process. Further, it is only necessary to insert the rod-shaped portion 9 of the poppet valve 8 into the through hole 4 of the protrusion 5 of the cylindrical case 1 and to caulk the upper end of the cylindrical case 1 to form the opening 7, as in the conventional example. There is no need to incorporate a spring into the device, and the assembly workability is good. Further, since it is not necessary to use a spring, the number of parts can be reduced. as a result,
The cost can be significantly reduced.

FIG. 4 is a sectional view showing a second embodiment of the present invention.

In FIG. 4, reference numeral 1 denotes a cylindrical case made of sheet metal, and a plurality of hydraulic passages 3 are formed in the bottom 2 of the cylindrical case 1 in the circumferential direction. A through hole 4 is formed at the center of the bottom 2, and a protrusion 5 protruding inward is formed around the through hole 4. A flat portion 6 is formed on the upper end of the protrusion 5.

A groove 12 is formed at the upper end opposite to the bottom 2 of the cylindrical case 1. A valve seat 13 is fitted into the groove 12, and the upper end of the cylindrical case 1 is swaged. The valve seat 13 is caulked and fixed to the opening 14 of the valve seat.

A hydraulic passage hole 15 for introducing a hydraulic pressure is formed in the valve seat 13, and the hydraulic passage hole 15 communicates with the opening 14 of the cylindrical case 1.

Reference numeral 8 denotes a poppet valve. The poppet valve 8 includes an elongated rod-like portion 9 and a spherical crown portion 10 attached to an end of the rod-like portion 9. The rod-shaped portion 9 is slidably housed in the through hole 4 of the cylindrical case 1, and the crown-shaped portion 10 is seated on the flat portion 6 of the projection 5 during normal operation without hydraulic backflow due to kickback. When the hydraulic pressure reverses due to the
Is closed. The poppet valve 8 is located at the bottom 2 of the cylindrical case 1.
And the hydraulic passage hole 15 of the valve seat 13 can be reliably opened and closed. With such a structure, the inclination and the left and right movement of the poppet valve 8 are regulated.

As shown in FIG. 3, a notch 11 is formed in the shoulder portion of the spherical crown portion 10 of the poppet valve 8, and the poppet valve 8 is seated in the hydraulic passage hole 15 of the valve seat 13, and the hydraulic passage hole When 15 is closed, the notch 11 forms an orifice hole that allows a part of the hydraulic oil to flow back.

At the time of normal operation in which hydraulic pressure flows, the rod-shaped portion 9 of the poppet valve 8 is inserted into the through hole 4 of the projection 5 and the spherical crown-shaped portion 10 is The seat 14 is seated on the flat portion 6, and the opening 14 of the cylindrical case 1 and the hydraulic passage hole 15 of the valve seat 13 are open. At this time, the inclination and the left and right movement of the poppet valve 8 are restricted.

In this state, hydraulic oil from the pump passes through the opening 14 of the cylindrical case 1 and passes through the valve seat 13.
Through the hydraulic passage hole 15, between the inner wall of the cylindrical case 1 and the poppet valve 8, and to the power cylinder through the hydraulic passage 2 of the cylindrical case 1. In this way, the rack shaft connected to the steered wheels is moved, and the operating force is assisted.

On the other hand, when traveling on an uneven road surface,
When the hydraulic oil flows backward due to kickback from the steered wheels, the hydraulic pressure enters through the hydraulic passage 2 of the cylindrical case 1 and presses the poppet valve 8. The poppet valve 8 responds to the flow of the hydraulic pressure at the time of kickback, and
4 and move upward in FIG. 4 to seat in the hydraulic passage hole 15 of the valve seat 13 and close the hydraulic passage hole 15. In this way, the backflow of the hydraulic oil when kickback is input is prevented, and the steering wheel is not taken.

The poppet valve 8 has a simple shape and is easy to process. In addition, since the structure is such that the inclination and the left and right movement of the poppet valve 8 are regulated, the operation is stable. The rod portion 9 of the poppet valve 8 is inserted into the through hole 4 of the projection 5 of the cylindrical case 1, and the valve seat 13 is provided.
It is only necessary to caulk the upper end of the cylindrical case 1 after forming the opening into the groove 12 to form the opening 14, and there is no need to incorporate a spring as in the conventional example, and the assembling workability is good. Further, since it is not necessary to use a spring, the number of parts can be reduced. As a result, costs can be significantly reduced.

[0049]

As described above, according to the present invention, the cylindrical case has a plurality of hydraulic passages at one end, a through-hole for the inside, and a projection having a flat portion at the top. The other end has an opening that can be swaged, and the poppet valve is attached to the rod-shaped part inserted into the through hole and the end of the rod-shaped part, sits on a flat part during normal operation, and closes the opening when the hydraulic pressure reverses. Because of the spherical crown, the inclination and the left and right movement of the poppet valve are regulated and the operation is stable, the shape of the poppet valve is simple and the assembly workability is good,
Further, the number of parts can be reduced.

As a result, the cost can be significantly reduced.

The same effect as described above can be obtained also by additionally providing a valve seat having a hydraulic passage hole fixed to the opening of the cylindrical case and communicating with the opening.

Further, a notch is formed in the spherical crown of the poppet valve to form an orifice groove when the opening of the cylindrical case or the hydraulic passage hole of the valve seat is closed. The part can be allowed to flow backward, and the operation of the valve can be further stabilized.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a first embodiment of the present invention.

FIG. 2 is a bottom view of a cylindrical case.

FIG. 3 is a view showing a cutout of a cylindrical case.

FIG. 4 is a cross-sectional view showing a second embodiment of the present invention.

FIG. 5 is a diagram showing a power steering apparatus using a conventional check valve.

FIG. 6 is a sectional view showing a conventional check valve.

[Explanation of symbols]

 1: Cylindrical case 2: Bottom 3: Hydraulic passage 4: Through hole 5: Projection 6: Flat portion 7, 14: Opening 8: Poppet valve 9: Rod 10: Spherical crown 11: Notch 12: Groove 13: Valve seat 15: Hydraulic passage hole

Claims (3)

[Claims] A power steering for operating a control valve by a handle to introduce hydraulic oil from a pump into one cylinder chamber of a power cylinder and return hydraulic oil from the other cylinder chamber to a reservoir tank to move a rack shaft. In a check valve used in the device, a cylindrical case having a plurality of hydraulic passages at one end, a projection having an inner through hole and a flat portion at the top, and an opening capable of being caulked at the other end. A rod-shaped portion inserted into the through-hole, a poppet valve attached to the end of the rod-shaped portion, having a spherical cap-shaped portion that is seated on a flat portion during normal operation and closes the opening portion when hydraulic pressure flows backward. A check valve comprising: 2. A power steering for operating a control valve by a handle to introduce hydraulic oil from a pump into one cylinder chamber of a power cylinder and return hydraulic oil from the other cylinder chamber to a reservoir tank to move a rack shaft. In a check valve used in the device, a cylindrical case having a plurality of hydraulic passages at one end, a projection provided with an inner through hole and an upper flat portion, and an opening capable of being caulked at the other end. A valve seat having a hydraulic passage hole fixed to the opening portion and communicating with the opening portion, a rod portion inserted into the through hole, and attached to an end of the rod portion and seated on a flat portion during normal operation. A check valve comprising: a poppet valve having a spherical crown portion for closing a hydraulic passage hole of the valve seat at the time of reverse flow of hydraulic pressure. 3. The check valve according to claim 1, wherein a cutout that forms an orifice groove when the opening or the hydraulic passage hole is closed is formed in the spherical portion of the poppet valve. Check valve.