JPS5919181Y2 - Temperature compensated throttle valve - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to a throttle valve provided with a temperature compensation function.

The prior art will be explained with reference to FIGS. 1 and 2.

A ring 3 press-fitted into a valve body guide hole 2 formed in the valve body 1 has a knife 6 at the opening 5 of the flow path 4.
is formed.

In addition, the valve body 7 has a knife 8 with a small diameter on its tip side.
is formed.

Variable orifice 9 by these knives 6.8
is configured.

In this variable orifice 9, both knife holes 6.8
The gap therebetween is changed by displacing the valve body 7 along the valve body guide hole 2, and the throttle amount is set accordingly.

By adjusting the throttle amount in this manner, the oil flow rate is less likely to decrease due to temperature changes, and the temperature compensation function is achieved.

In this prior art, in order to form the orifice 9, a ring rod having a knife 6 is press-fitted into the valve body guide hole 2 with an appropriate press-fitting amount.

In order to properly press-fit and fix the ring 3 into the valve body guide hole 2 in this manner, it is necessary to improve the dimensional accuracy of the valve body guide hole 2.

Therefore, after cutting, it is necessary to finish by reaming or honing.

However, the finished portion has a small hole diameter and is located at the deepest part of the valve body 1.

Moreover, since the valve body guide hole 2 is not a through hole but a closed hole due to the valve seat 10, it is difficult to measure the dimensions during drilling and the drilling itself, resulting in poor processing efficiency. .

Furthermore, in this prior art, the knife 6 of the ring 3 is formed corresponding to the opening 5 of the flow path 4, so the orifice 9 can only be formed at one location on the circumference.

Therefore, it is not possible to flow a large amount of oil.

In order to flow a large amount of oil, a simple idea is to form the opening 5 in the shape of a groove along the circumference of the ring 3, as shown in FIGS. 3 and 4.

In this way, the knife grooves 6 can be formed in a plurality of locations, making it possible to flow a large amount of oil. Since it is thin, about 0.3 mm, there is a risk that the knife 6 part may break.

Furthermore, as shown in FIGS. 5 and 6, it is simply conceivable to form a groove 11 in the valve body 1 corresponding to the opening of the flow path 4.

Although it is possible to form a plurality of knife screws 6 in this way and allow a large amount of oil to flow, it becomes more difficult to process the large ring pressure hole in the valve body 1 and measure the inner diameter dimension, and the press-fitting operation also requires careful work. , work efficiency will decrease significantly.

An object of the present invention is to solve the above-mentioned technical problems and provide a temperature-compensated throttle valve having a structure that improves processing efficiency.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 7 is an overall sectional view of an embodiment of the present invention.

In this temperature-compensated throttle valve 15, the pressure oil flowing into the connecting end 16 in the direction shown by the arrow 17 is throttled by a plurality of variable orifices 18 and flows from the connecting end 19 in the direction shown by the arrow 20. .

Moreover, the pressure oil flowing into the connection end 19 in the direction opposite to the arrow 20 is
It flows out from the connecting end 16 through the check valve 21 in the direction opposite to the arrow 17 .

The valve body 22 of the temperature compensated throttle valve 15 is formed by integrally fixing a rectangular parallelepiped-shaped base 23 and a basically cylindrical guide body 24.

The base body 23 has a connecting end 16 to which a conduit 25, 26 is connected.
．． 19 are formed respectively.

One connecting end 16 communicates with a side of a fitting hole 27 extending perpendicularly to the connecting end 16 .

A check valve 21, which is formed from a valve body 28, a spring 29, and a spring receiver 30, is fitted into the fitting hole 27.

A valve hole 31 to be closed by seating the valve body 28 communicates with the other connecting end 19 via a flow path 32 .

A recess 33 is formed in the end face of the base body 23 opposite the two connecting ends 16,19.

This recess 33 has a large-diameter fitting portion 34 connected to the large-diameter fitting portion 34 via a surface 35 and a circular hole portion 36 having a smaller diameter than the large-diameter fitting portion 34 in order from the outside to the inside. , a small-diameter fitting portion 37 having a smaller diameter than the circular hole portion 36 is formed concentrically.

A valve seat 38 is provided concentrically at the end of the circular hole 36 , and the end communicates with the flow path 32 via a valve hole 39 .

One end of a channel 40 extending along the axial extension of the connecting end 16 communicates with the fitting hole 27 , and the other end of this channel 40 opens into the circular hole portion 36 .

Further, the valve body 28 of the check valve 21 has a small hole 41 that opens in the radial direction at an arbitrary position on the circumference.

When the check valve main body 28 opens (when the check valve 28 moves to the left), the oil inside the fitting hole 27 flows out through the small hole 41, preventing oil from being trapped, and conversely, the oil inside the fitting hole 27 flows out from the small hole 41, preventing the oil from being trapped. When the check valve 28 is closed (when the check valve 28 moves to the right), the inside of the fitting hole 27 becomes negative pressure, so oil flows into the inside through the small hole 41.

Further, the outer diameter of the check valve 28 becomes narrower at the small hole 41 portion.

Therefore, with the check valve 21 closed, the pressure oil that has flowed into the connection end 16 passes through the communication hole 41 and the outer periphery of the check valve 28 and flows into the flow path 40 .

The guide body 24 is inserted into the recess 33 of the base body 23 and fixed thereto, and has a valve body guide hole 42 formed to penetrate in the axial direction.

A portion of the guide body 24 near the recess 33 has a recess 3
A small-diameter cylindrical portion 43 that is loosely fitted into the small-diameter fitting portion 37 of No. 3
and a large diameter cylindrical portion 44 that is loosely fitted into the large diameter fitting portion 34.
The small-diameter cylindrical portion 43 and the large-diameter cylindrical portion 44 are connected via a stepped surface 45 that is received by the receiving surface 35 .

When the guide body 24 is inserted into the recess 33 and fixed, an annular flow path 46 is formed between the outer circumferential surface of the small diameter cylindrical portion 43 and the inner surface of the circular hole portion 36. The flow path 40 is in communication.

Further, the axial length of the small diameter cylindrical portion 43 from the step surface 45 is as follows:
When the stepped surface 45 comes into contact with the receiving surface 35, the small diameter cylindrical portion 4
3 is selected so that the tip thereof does not come into contact with the bottom of the small diameter fitting portion 37.

FIG. 8 is an enlarged sectional view of the vicinity of the small diameter cylindrical portion 43 of the guide body 24.

A plurality of knife blades 47 are formed at intervals in the circumferential direction in a portion of the small diameter cylindrical portion 43 facing the flow path 46 .

Further, a through hole 48 is formed in the small diameter cylindrical portion 43 surrounded by the knife 47, and the flow path 46 and the valve body guide hole 42 communicate with each other through the through hole 48.

A valve body 49 is inserted into the valve body guide hole 42 .

The valve body 49 moves along its axis along the inside of the valve body guide hole 42 due to the screw feeding action caused by the threaded engagement between the external thread 50 carved on the valve body 49 and the internal thread 51 carved on the inner surface of the valve body guide hole 42. It can be freely displaced in any direction.

A knob 52 that covers the outer end of the guide body 24 is integrally fixed to the valve body 49 .

Furthermore, the engagement between the inward protrusion 53 fixed to the knob 52 and the annular groove 54 formed on the outer periphery of the guide body 24 limits the axial displacement amount of the valve body 49 and therefore the opening degree of the throttle valve. The valve body 49 is prevented from coming off from the guide body 24.

The valve body 49 is formed with a knife 56 having a smaller diameter on the tip 55 side, corresponding to the knife 47 of the small diameter cylindrical portion 43 .

The variable orifice 18 is constituted by these knife blades 47 and 56.

A tip 57 of the valve body 49 is formed into a tapered conical shape, and this tip 57 is seated on the valve seat 38.

When supplying pressure oil from the connection end 16, the valve body 49
The valve hole 39 is closed when the tip 57 of the valve seat 38 is in sealing contact with the valve seat 38, and at the same time the valve hole 39 is closed.
7.56 overlap and the variable orifice 18 is closed.

In this state, the small diameter fitting part 37 of the basic 23 and the small diameter cylindrical part 4
Even if there is a slight gap between the valve and the valve seat 3 and there is a leakage of pressure oil, the tip 57 is seated on the valve seat 38, so the leakage of the pressure oil is completely prevented.

Assume that the valve body 49 is moving away from the valve seat 38.

As the lift of the valve body 49 increases, the variable orifice 18
The aperture area (indicated by line 11 in FIG. 9) is at the tip 57
The opening area is always smaller than the opening area (indicated by line 12 in FIG. 9) between the valve seat 38 and the valve seat 38, regardless of the size of the software.

Therefore, the flow rate controlled by the variable orifice 18 is not suppressed to a small value by the tip 57 and the valve seat 38, making it possible to accurately control the throttling amount and preventing the temperature compensation function from being lost.

Referring to FIG. 10, when the valve body 49 is displaced to slightly open the space between the tip 57 and the valve seat 38, the variable orifice 1
8 leaks from the flow path 46 to the flow path 32 as shown from a to b in FIG.

This leakage flow rate is proportional to the length of the overlap part and the pressure difference between the inlet and outlet, and is proportional to the cube of the gap between the valve body 49 and the small diameter cylindrical part 43, and the gap between the small diameter cylindrical part 43 and the small diameter fitting part 37. However, since the tip 57 is in close contact with the valve seat 38, there is no leakage from the flow path 46 to the flow path 32.

Further, when the gap between the tip 57 and the valve seat 38 is opened, the leakage increases from b to C, but the variable orifice 18 remains closed.

Point 0 is the point at which the overlap between the two knife tubes 47 and 56 becomes zero and they begin to open. From then on, as the lift of the valve body 49 increases, the variable orifice 18 opens, and the aperture area and therefore the flow rate become C-) d. It keeps increasing.

Point e on the extension line of d-+C is the point at which the variable orifice 18 starts to open, assuming that the leakage from the overlapped portion of the variable orifice 18 is zero.

Therefore, the portion surrounded by al)-c-e in FIG. 10 is the amount of leakage from the variable orifice 18.

Due to this amount of leakage, the rising characteristic of the amount of outflow after opening of the tip 57 and the valve seat 38 becomes gentle, and the actuator can be started very minutely.

Note that the above orifice flow rate characteristics are experimental results for one orifice, but even for multiple orifices, the characteristics shown in Figures 9 and 9 can be obtained by appropriately selecting the size, shape, and axial position of the orifices. It is possible to freely change the characteristics shown in Figure 10.

When assembling the valve body 22 of such a temperature compensation function valve 15, the small diameter cylindrical portion 43 of the guide body 24 is loosely fitted into the small diameter fitting portion 37 in the recess 33 of the base body 23, and the size of the guide body 24 is adjusted. The diameter cylindrical portion 44 is fitted into the large diameter fitting portion 34 of the recess 33, and the stepped surface 45 is brought into contact with the receiving surface 35.

In this state, the large diameter cylindrical portion 44 and the large diameter fitting portion 34 of the guide body 24 are fixed together by brazing or the like.

As a result, the base body 23 and the guide body 24 are integrally fixed to form the valve body 22.

In this way, the large diameter cylindrical part 44 and the small diameter cylindrical part 4 of the guide body 24 are attached to the large diameter fitting part 34 and the small diameter fitting part 37 of the base body 23.
3 is fitted with a loose fit, so the large diameter fitting part 34
Also, the concentricity and dimensional accuracy of the small-diameter fitting portion 37 need be relatively rough, and processing efficiency is improved.

Note that since the small diameter cylindrical portion 43 is loosely fitted into the small diameter fitting portion 37, the variable orifice 18 will not be compressed and deformed even after they are fixed together.

As described above, according to the present invention, the dimensional accuracy of the recess in the composite body can be made relatively rough, so that the processing efficiency of the valve body is improved.

Moreover, since multiple orifices are provided, a large amount of oil can flow.

[Brief explanation of drawings]

Fig. 1 is a sectional view showing the prior art, Fig. 2 is a sectional view taken from section line II--I in Fig. 1, and Fig. 3 is a structure easily conceived to solve the problems of the prior art. 4 is a sectional view taken from section line IVIV in FIG. 3,
FIG. 5 is a cross-sectional view showing a structure that can be easily conceived to solve the problems of the prior art, and FIG. 6 is a cross-sectional view showing the section line VI of FIG.
7 is an overall sectional view of an embodiment of the present invention, FIG. 8 is an enlarged sectional view of the vicinity of the small diameter cylindrical portion 43 of the guide body 24, and FIG. 9 is a lift of the valve body 49. FIG. 10 is a graph showing the relationship between the lift of the valve body 49 and the flow rate from the flow path 46 to the flow path 32. 15...Temperature compensated throttle valve, 18...
Variable orifice, 22... Valve body, 23...
... Base body, 24 ... Guide body, 32, 46 ...
...Flow path, 33...Recess, 34...
・Large diameter fitting part, 35...The receiver is a surface, 36...
...Round hole part, 37...Small diameter insertion part, 38...
...Valve seat, 39...Valve hole, 42...
Valve body guide hole, 43... Small diameter cylinder part, 44...
・・Large diameter cylindrical portion, 45 ・・Step surface, 47, 56・
・・・・・・Naifetsuji, 49・・・・・・Valve body, 57
・・・・・・Tip.

Claims (1)

[Claim for Utility Model Registration] A knife provided at the opening of a flow path opened on the side of the valve body guide hole, and a knife provided with a smaller diameter on the tip side of the valve body inserted into the valve body guide hole. A variable orifice is formed by the valve body guide hole, and a valve seat on which the tip of the valve body is seated is provided at the end of the valve body guide hole, and a valve hole that communicates the end of the valve body guide hole with another flow path; A temperature compensated throttle valve configured such that the throttle area of the variable orifice is smaller than the opening area between the tip of the valve body and the valve seat, and the variable orifice is closed when the tip of the valve body is seated on the valve seat. The main body includes a small-diameter fitting part concentrically connected to the valve hole via the valve seat, a circular hole part having a larger diameter than the small-diameter fitting part, and a circular hole having a larger diameter than the circular hole part and having a receiving part through a surface. a base body comprising a recess having large-diameter fitting portions in order and concentrically connected to the small-diameter fitting portion; a small-diameter cylindrical portion loosely fitted in the small-diameter fitting portion and having a plurality of knife holes formed in the circumferential direction; The large diameter cylindrical part has a large diameter cylindrical part that is connected to the small diameter cylindrical part through a stepped surface that is brought into contact and is gently fitted into the large diameter fitting part, and is provided with a valve body guide hole, and the large diameter cylindrical part and a temperature-compensated throttle valve characterized in that the large-diameter fitting portion is integrally fixed.