KR102272284B1 - pressure control valves using multi-step springs with precision pressure control - Google Patents

Abstract

The present invention relates to a multi-step spring pressure control valve capable of precision pressure control. The multi-step spring pressure control valve capable of precision pressure control comprises: a housing having an inlet and an outlet to supply and discharge a fluid, and formed to have a hollow space therein to accommodate various members and fluids; a guide pipe formed in the housing, and discharging the fluid entering through the inlet in a set direction; a poppet formed on the upper end of the guide pipe, and opened and closed while being separated from the guide pipe in accordance with the pressure of the entering fluid to discharge the fluid; and an elastic unit formed in the housing, wherein one end thereof presses the poppet toward the guide pipe to prevent the fluid from being discharged from the guide pipe. A fluid force acts in the direction in which the poppet is opened and the fluid force offsets a spring force. Multiple springs are used, and the effective modulus of elasticity of the springs matches the modulus of elasticity of a fluid force spring to improve the precision of pressure control of the valve.

Description

Pressure control valves using multi-step springs with precision pressure control

The present invention relates to a multi-stage spring pressure control valve capable of precise pressure control, and more particularly, a precision pressure control capable of reducing and constantly maintaining a pressure change generated as the flow rate of a fluid supplied into the valve increases. It relates to a multi-stage spring pressure control valve.

In general, a pressure control valve is used to maintain a constant or set pressure in a hydraulic circuit or mechanism, and to prevent overload due to an increase in pressure in the hydraulic circuit or mechanism.

The pressure control valve includes a relief valve, a sequence valve, a counterbalance valve, a pressure reducing valve, and the like, and the structure of the pressure control valve will be described using the structure of the relief valve.

1 is a simplified view of the internal structure of a conventional relief valve, as shown in FIG. 1 , the inside is empty and the inlet 13 through which the fluid is introduced is formed at the bottom, and the outlet 14 through which the fluid is discharged on the side ) formed in the housing 10, the poppet 11 formed in the inlet 13 of the housing 10 and opened and closed while closely or spaced apart from the inlet 13, and the poppet 11 formed in the upper portion of the poppet 11 ) consists of a spring 12 that presses the inlet 13 toward the direction.

In the poppet 11, when the pressure of the fluid is higher than the elastic force of the spring 12, the poppet 11 is spaced apart from the inlet 13 and the fluid flows into the housing 10, the fluid flow near the poppet 11 Since the fluid force acts in the direction in which the poppet 11 is closed, the force to close the poppet 11 is increased, causing a pressure increase, and thus there is a problem in that the pressure in the hydraulic circuit or mechanism cannot be precisely controlled.

2 shows a relief valve whose structure is improved so that the flow of fluid acts in the direction in which the poppet 11 opens, and the fluid flows into the poppet 11 and pushes the poppet 11. It is suggested that the physical strength cancels the elastic force of the spring 12 to enable precise control.

However, even in the structure shown in FIG. 2 , there is a problem in that the precision of pressure control is lowered in the pressure region in which the elastic force of the spring 12 shows a difference from the fluid force generated while the fluid flows.

Korean Patent Publication No. 10-2004-0009556

An object of the present invention for solving the above problems is to reduce the difference between the elastic force of the spring and the fluid force generated while the fluid flows, thereby enabling precise pressure control that can precisely control the pressure control of the hydraulic circuit or mechanism. To provide a pressure control valve.

Another object of the present invention is to provide a multi-stage spring pressure control valve capable of precise pressure control that reduces the error pressure generated by the fluid force by determining the elastic force of the spring according to the fluid force generated while the fluid flows.

In order to solve the above problems, the multi-stage spring pressure control valve capable of precise pressure control of the present invention has an inlet and an outlet so that the fluid can be supplied and discharged, and the inside is hollow to accommodate various members and fluids. The housing is formed, the guide tube is formed inside the housing and discharges the fluid drawn in through the inlet in a set direction, and the guide tube is formed at the top of the guide tube and opens and closes while being spaced apart from the guide tube according to the pressure of the incoming fluid to release the fluid. It is characterized in that it comprises a poppet for discharging, and an elastic part formed inside the housing and having one end spring formed in multiple stages to prevent the fluid from being discharged from the guide tube by pressing the poppet in the direction of the guide tube.

In addition, the multi-stage spring pressure control valve capable of precise pressure control of the present invention includes a pressing end formed inside the housing and formed to support the other end of the multi-stage spring; One end is connected to the pressing end and the other end is formed on the outside of the housing to move the pressing end toward the poppet according to the rotational direction, characterized in that it further comprises an adjustment screw for adjusting the elastic force of the elastic part.

In addition, the pressing end of the multi-stage spring pressure control valve capable of precise pressure control of the present invention further includes a plurality of fixing grooves digging in a circular direction inward to support the multi-stage spring of the elastic part, and the fixing grooves are multi-stage. It is characterized in that the position of the spring in a no-load state that is not in contact with the poppet is fixed among the springs.

In addition, the elastic part of the multi-stage spring pressure control valve capable of precise pressure control of the present invention consists of a plurality of springs having different lengths, and the plurality of springs sequentially contact the poppet when the pressure increases according to the flow of the flowing fluid. It is characterized in that the fluid is discharged under a constant pressure by reducing the pressure generated by the flow of the fluid.

In addition, the poppet of the multi-stage spring pressure control valve capable of precise pressure control of the present invention has a pressure groove formed at the center of the lower end to which the pressure of the fluid is applied so that it can be separated from the guide tube by the pressure of the fluid flowing from the guide tube. characterized.

In addition, when the poppet of the multi-stage spring pressure control valve capable of precise pressure control of the present invention is separated from the guide tube by the pressure of the fluid, the fluid flows through the gap inclined downward between the poppet and the guide tube, and by the flow of the fluid It is characterized in that the generated fluid force induces the poppet to act in the opening direction.

In addition, the elastic part of the multi-stage spring pressure control valve capable of precise pressure control of the present invention is characterized in that the elastic modulus of the elastic part is changed according to the elastic modulus of the fluid force spring which is changed by the pressure of the fluid using a plurality of springs in multi-stage. do it with

As described above, according to the multi-stage spring pressure control valve capable of precise pressure control according to the present invention, the difference between the elastic force of the spring and the fluid force generated while the fluid flows is reduced to precisely control the pressure control of the hydraulic circuit or mechanism. can have an effect.

In addition, according to the multi-stage spring pressure control valve capable of precise pressure control according to the present invention, there is an effect of reducing the error pressure generated by the fluid force by determining the elastic force of the spring according to the fluid force generated while the fluid flows.

1 is a view schematically showing the internal structure of a conventional relief valve.
Figure 2 is a view schematically showing the internal structure of the improved relief valve.
Figure 3 is a cross-sectional view showing a closed state of the poppet of the multi-stage spring pressure control valve capable of precise pressure control according to the present invention.
4 is a cross-sectional view showing a state in which the poppet of the multi-stage spring pressure control valve capable of precise pressure control according to the present invention is opened, the first spring is compressed and the second spring is in contact.
5 is a cross-sectional view showing a state in which the poppet of the multi-stage spring pressure control valve capable of precise pressure control according to the present invention is opened, the first spring and the second spring are compressed, and the third spring is in contact.
6 is a cross-sectional view showing a state in which the initial set pressure is increased by compressing the first spring using the adjusting screw of the multi-stage spring pressure control valve capable of precise pressure control according to the present invention and allowing the second spring to contact the poppet.
7 shows a state in which the initial set pressure is increased by compressing the first and second springs using the adjusting screw of the multi-stage spring pressure control valve capable of precise pressure control according to the present invention and allowing the third spring to contact the poppet. Cross-section.
8 is a cross-sectional view showing the shape of the pressing end of the multi-stage spring pressure control valve capable of precise pressure control according to the present invention.
9 is an enlarged view showing an enlarged portion A of the multi-stage spring pressure control valve capable of precise pressure control according to the present invention.
10 is a graph showing the correlation between the elastic modulus of the spring and the elastic modulus of the fluid force of the multi-stage spring pressure control valve capable of precise pressure control according to the present invention.
11 is a graph showing the correlation of pressure according to the flow rate of the multi-stage spring pressure control valve capable of precise pressure control according to the present invention, and at the same time, the correlation between the pressure according to the flow rate of the multi-stage spring pressure control valve and the existing pressure of FIG. A graph comparing the pressure-flow correlation between the control valve and the improved pressure control valve of FIG. 2 .

Specific features and advantages of the present invention will be described in detail below with reference to the accompanying drawings. Prior to this, if it is determined that the detailed description of the function and its configuration related to the present invention may unnecessarily obscure the gist of the present invention, the detailed description will be omitted.

The present invention relates to a multi-stage spring pressure control valve capable of precise pressure control, and more particularly, a precision pressure control capable of reducing and constantly maintaining a pressure change generated as the flow rate of a fluid supplied into the valve increases. It relates to a multi-stage spring pressure control valve.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

3 to 5 are cross-sectional views sequentially showing a state in which the poppet of the multi-stage spring pressure control valve capable of precise pressure control according to the present invention is gradually opened, and FIGS. 6 and 7 are multi-stage spring pressures capable of precise pressure control according to the present invention. It is a cross-sectional view showing the state in which the initial set pressure is adjusted using the adjusting screw of the control valve, and FIG. 8 is a cross-sectional view showing the shape of the pressing end of the multi-stage spring pressure control valve capable of precise pressure control according to the present invention, and FIG. It is an enlarged view showing an enlarged portion A of the multi-stage spring pressure control valve capable of precise pressure control according to the present invention.

3 to 9, in the multi-stage spring pressure control valve capable of precise pressure control according to the present invention, an inlet 110 and an outlet 120 are formed so that a fluid can be supplied and discharged, and the inside is hollow. and a housing 100 formed to accommodate various members and fluids, and an induction pipe 300 formed inside the housing 100 and discharging the fluid introduced through the inlet 110 in a set direction; , a poppet 200 formed at the upper end of the guide tube 300 and opened and closed to discharge the fluid while being spaced apart from the guide tube 300 according to the pressure of the incoming fluid, and the poppet 200 is formed inside the housing 100 and has one end of the poppet It is characterized in that it includes an elastic part 400 in which a spring is formed in multiple stages so that the fluid is not discharged from the guide tube 300 by pressing the 200 in the direction of the guide tube 300 .

In addition, the pressing end 500 is formed inside the housing 100 and formed to support the other end of the multi-stage spring, and one end is connected to the pressing end 500 and the other end is formed outside the housing 100 in the direction of rotation. It is characterized in that it further includes an adjustment screw 600 for adjusting the elastic force of the elastic part 400 by moving the pressing end 500 toward the poppet 200 according to the present invention.

In addition, the poppet 200 is characterized in that the pressure groove 210 to which the pressure of the fluid is applied is formed in the center of the lower end so as to be spaced apart from the guide tube 300 by the pressure of the fluid flowing from the guide tube 300 . do.

When the poppet 200 is spaced apart from the guide pipe 300 by the pressure of the fluid, the fluid flows into a gap inclined downward between the poppet 200 and the guide pipe 300, and the flow generated by the flow of the fluid It is characterized in that the stamina induces the poppet 200 to act in the opening direction.

The housing 100 is for supporting various members therein. The inside is empty, and an inlet is formed on the lower surface to allow fluid to flow in, and the fluid introduced into the housing 100 is discharged from the side on the side. A discharge hole is formed so that it can be discharged.

A through hole is formed in the upper surface of the housing 100 so that one end of the adjusting screw 600 can be inserted into the housing 100 , and a thread is formed in the through hole in the rotation direction of the adjusting screw 600 . Accordingly, the adjusting screw 600 can be inserted or retracted into the housing 100 .

The poppet 200 is kept in close contact with the guide tube 300 by the elastic force of the elastic part 400, and the guide tube 300 is kept closed before the fluid reaches a set pressure so that the fluid flows into the housing 100. ) to prevent it from being discharged to the outside.

The induction pipe 300 is formed in the inlet 110 through which the fluid is introduced into the housing 100, and the pressure groove 210 formed in the center of the poppet 200 formed thereon for the fluid flowing in from the inlet 110 is inside. lead to influx.

The fluid is introduced into the pressurizing groove 210 dug inward in the center of the lower end of the poppet 200 through the guide tube 300 to press the poppet 200, and when the fluid pressure is increased, the first spring 410 is As the poppet 200 is gradually compressed, a gap is generated as the poppet 200 is spaced apart from the guide tube 300 , and the fluid introduced into the pressure groove 210 can move into the housing 100 through the gap.

At this time, when the poppet 200 is spaced apart from the guide tube 300 by the pressure of the fluid introduced into the poppet 200 , when the fluid exits the gap between the poppet 200 and the guide tube 300 , the fluid force is generated by the poppet. The gap between the poppet 200 and the guide tube 300 is formed to flow in the opposite direction of the poppet 200 to act in the opening direction, and to form an appropriate opening fluid force.

That is, in order for the fluid to generate a fluid force in the direction in which the poppet 200 is opened, the pressure groove 210 is formed with a first inclined surface 220 whose diameter gradually decreases as the pressure groove 210 enters the inside of the poppet 200 is formed, and is guided The upper edge of the tube 300 has a second inclined surface 310 corresponding to the first inclined surface 220 to be in close contact with the first inclined surface 220, so that the discharged fluid is pressed by the fluid along the inclined surface. It is preferable to discharge in the opposite direction of the moving poppet 200 .

The elastic part 400 presses the poppet 200 so that it is in close contact with the upper end of the guide tube 300 before the pressure generated in the hydraulic circuit or mechanism reaches the set pressure, so that the fluid is discharged to the outside through the outlet 120 . This is to press the poppet 200 so as not to be discharged.

At this time, the elastic part 400 is composed of a plurality of springs having different lengths, and the plurality of springs sequentially contact the poppet when the pressure is increased according to the flow of the flowing fluid, thereby reducing the pressure generated by the flow of the fluid. It is characterized in that the fluid is discharged under a constant pressure.

A plurality of springs are formed in the elastic part 400 in multiple stages, and have different lengths in a free state, thereby sequentially pressing the poppet 200 according to the pressure flowing into the housing 100 .

In the present invention, the first spring 410, the second spring 420, and the third spring 430 will be described using the elastic part 400, the spring constituting the elastic part 400 is a fluid input The number, elastic modulus, and length may vary depending on the applied pressure and fluid flow.

In addition, the elastic part 400 is characterized in that the elastic modulus of the elastic part 400 is changed according to the elastic modulus of the fluid force spring that is changed by the pressure of the fluid by using a plurality of springs in multiple stages.

3, since the first spring 410, the second spring 420, and the third spring 430 have different lengths, only the first spring 410 is in contact with the poppet 200 in a no-load state. state, and the second spring 420 and the third spring 430 are spaced apart from the poppet 200 .

At this time, the second spring 420 is spaced apart from the upper end of the poppet 200 by the gap G1 , and the third spring 430 is spaced apart from the second spring 420 by the gap G2 .

When the pressure of the fluid is increased than the elastic force of the first spring 410 , the poppet 200 is moved upward while the first spring 410 is compressed, thereby causing a gap between the poppet 200 and the guide tube 300 . is generated, the fluid introduced into the pressing groove 210 of the poppet 200 is introduced into the housing 100 through the gap and then discharged.

When the pressure of the input fluid itself increases or the pressure increases according to the flow of the fluid, the second spring 420 is brought into contact with the upper end of the poppet 200 while the poppet 200 is moved upward. The elastic force of the first spring 410 and the second spring 420 is applied thereto.

That is, when a pressure higher than the elastic force of the first spring 410 is generated, the poppet 200 is pressed and moved upward. When the poppet 200 is in contact with one end of the second spring 410 , the first spring 410 . The poppet 200 is moved only when the pressure of the fluid is higher than the sum of the elastic forces of the and the second spring 420 .

In addition, when the pressure of the fluid is continuously increased, the poppet 200 comes into contact with one end of the third spring 430 , and in this case, the fluid is the first spring 410 , the second spring 420 , and the third spring 430 . ), the poppet 200 is moved when a higher pressure than the elastic force is applied.

Therefore, it is possible to control the pressure at which the fluid is discharged step by step using the first spring 410 , the second spring 420 , and the third spring 430 , and a phenomenon in which the pressure is increased by the flow of the fluid occurs. However, it is possible to compensate for this and precisely control the pressure.

That is, as the first spring 410 , the second spring 420 , and the third spring 430 of the elastic part 400 are sequentially operated according to the pressure of the fluid, the modulus of elasticity of the elastic part 400 is a fluid force spring. It can be changed according to the modulus of elasticity of

6 to 7, in order to adjust the elastic force of the elastic part 400, the pressing end 500 is connected to the adjusting screw 600 formed outside the housing 100, and the adjusting screw 600 is rotated. By moving the pressing end 500 toward the poppet 200 so that the spring is compressed, the elastic force of the spring can be adjusted, and through this, the pressure range of the fluid in which the poppet 200 is opened and closed can be adjusted.

The adjusting screw 600 is connected to the pressing end 500 formed inside the housing, and the pressing end 500 presses the other end of the first spring 410 , the second spring 420 , and the third spring 430 . formed to be able to do it.

When the pressing end 500 is lowered, the first spring 410 in contact with the poppet 200 is compressed, and the second spring 420 and the third spring 430 move toward the poppet 200 .

At this time, when the pressing end 500 descends by the gap G1 between the second spring 420 and the upper end of the poppet 200, the second spring 420 is kept in contact with the upper end of the poppet 200 as shown in FIG. will become

In this case, the poppet 200 is opened only when a pressure higher than the elastic force of the first spring 410 and the second spring 420 is applied to the set pressure for opening the poppet 200, so that the set pressure at which the fluid is discharged can be increased. there will be

In addition, in this state, when the pressing end 500 descends further by the gap G2 between the second spring 420 and the third spring 430, the first spring 410 and the second spring 420 are compressed and the second spring 420 is compressed. 3 spring 430 is in contact with the upper end of the poppet 200, and the pressure of the discharged fluid is higher than the sum of the elastic forces of the first spring 410, the second spring 420, and the third spring 430. You can set it to be released.

As shown in FIG. 8 , the pressing end 500 further includes a plurality of fixing grooves 510 digging in a circle in an inner direction to support the multi-stage spring of the elastic part 400 , the fixing grooves Reference numeral 510 is characterized in that the position of the spring in a no-load state that is not in contact with the poppet 200 among the multi-stage springs is fixed.

The fixing groove 510 is a first spring 410 and a second spring 420 are compressed on the lower surface of the pressing end 500 and is cut in a circle so that the third spring 430 can be inserted, the fixing groove It is preferable that the other ends of the first spring 410 , the second spring 420 , and the third spring 430 are fixed to the 510 .

When the poppet 200 is moved by being pressurized by the fluid through the fixing groove 510, the first spring 410, the second spring 420, and the third spring 430 can be compressed while the position is fixed. Therefore, it is possible to apply the elastic force to the poppet 200 in a more stable state.

3 to 9 will be described with respect to the detailed operating principle.

When the pressing end 500 is moved toward the poppet 200 by rotating the adjusting screw 600 , the elastic part 400 is compressed to increase the compressive force of the multi-stage spring, and through this, the fluid pressure for opening the poppet 200 . The set value will also increase.

When the pressure on the inlet 110 side of the housing 100 is increased, the force acting in the direction to open the poppet 200 from the guide tube 300 also increases, and this opening force is applied to the elastic force of the elastic part 400 . When it is reached, the poppet 200 is in a state just before opening.

This instantaneous pressure is called cracking pressure and can be thought of as a set pressure that the user wants to control.

)과 스프링력(

)은 서로 평형을 이루며, 다음 수학식 1과 같이 표현된다.In the cracking state just before the poppet 200 opens, the static hydraulic force (

) and spring force (

) are in equilibrium with each other, and are expressed as in Equation 1 below.

: 크래킹 상태의 스프링력,

: 스프링 탄성계수,

: 스프링 초기 압축 변위,

: 크래킹 압력 ,

: 가압홈(210) 면적,

: 가압홈(210) 내부 지름,

: 정적 유압력)(

: Spring force in cracking state,

: spring modulus of elasticity,

: spring initial compression displacement,

: cracking pressure ,

: Pressing groove 210 area,

: the inner diameter of the pressing groove 210,

: static hydraulic force)

)이 영(0)이며, 유량이 증가하기 위해서는 포핏(200) 열림 변위(x)가 증가하여야 하는데, 그러한 관계식은 수학식 2와 같이 주어진다.In this cracking state, the flow rate (

) is zero (0), and in order to increase the flow rate, the opening displacement (x) of the poppet 200 must increase. Such a relational expression is given by Equation (2).

: 유량,

: 유량 계수,

: 포핏(200) 변위,

: 포핏(200) 부위의 유체 분출각,

: 유체 밀도,

: 포핏(200) 상류측 압력,

: 포핏(200) 하류측 대기압(

))(

: flow rate,

: flow coefficient,

: Poppet (200) displacement,

: Fluid ejection angle of the poppet 200,

: fluid density,

: Poppet 200 upstream pressure,

: Poppet (200) downstream atmospheric pressure (

)))

Here, the upstream side of the poppet 200 means the vicinity of the inside of the pressing groove 210 , and the downstream side of the poppet 200 means the vicinity of the outside of the pressing groove 210 .

)의 증가는 각각 유체력(flow force,

)과 스프링의 압축력(

)을 증가시키게 되는데, 각각 수학식 3과 수학식 4로 표현된다.Increase in flow and displacement of poppet 200 opening (

) increases with the flow force (flow force,

) and the compression force of the spring (

) is increased, which is expressed by Equations 3 and 4, respectively.

: 유체력,

: 유량,

: 유량 계수,

: 포핏(200) 변위,

: 포핏(200) 부위의 유체 분출각,

: 유체 밀도,

: 포핏(200) 상류측 흐름 단면적)(

: fluid force,

: flow rate,

: flow coefficient,

: Poppet (200) displacement,

: Fluid ejection angle of the poppet 200,

: fluid density,

: Poppet (200) upstream flow cross-sectional area)

) 항목은 포핏(200) 상류측 흐름 단면적

값이 포핏(200) 열림 면적(

)보다 매우 크기 때문에 무시될 수 있다.described in the second term of the second line of Equation 3 (

) is the poppet 200 upstream flow cross-sectional area

The value is the poppet (200) opening area (

), so it can be ignored.

: 스프링의 압축력,

: 스프링 탄성계수,

: 포핏(200) 변위)(

: the compression force of the spring,

: spring modulus of elasticity,

: Poppet (200) displacement)

)와 밸브 통과 유량에 대하여 포핏(200)을 닫아주는 방향으로 작용하는 스프링력과 열어주는 방향으로 작용하는 유체력은 서로 평형을 이루게 되며, 다음의 수학식 5 및 수학식 6으로 표현된다.Poppet (200) displacement (

) and the spring force acting in the direction to close the poppet 200 and the fluid force acting in the direction to open the poppet 200 with respect to the flow rate through the valve are in equilibrium with each other, and are expressed by Equations 5 and 6 below.

: 크래킹 상태의 스프링력,

: 스프링의 압축력,

: 크래킹 상태에서 정적 유압력,

: 유체력)(

: Spring force in cracking state,

: the compression force of the spring,

: static hydraulic force in cracking condition,

: fluid force)

: 스프링 탄성계수,

: 스프링 초기 압축 변위,

: 포핏(200) 변위,

: 유체 밀도,

: 가압홈(210) 면적,

: 유량 계수,

: 가압홈(210) 내부 지름,

: 포핏(200) 부위의 유체 분출각,

: 유체 스프링의 탄성계수)(

: spring modulus of elasticity,

: spring initial compression displacement,

: Poppet (200) displacement,

: fluid density,

: Pressing groove 210 area,

: flow coefficient,

: the inner diameter of the pressing groove 210,

: Fluid ejection angle of the poppet 200,

: modulus of elasticity of fluid spring)

에 비례하여, 포핏(200)을 열어주는 방향으로 작용하는 유체 스프링으로 간주할 수 있으며, 유체 스프링의 탄성 계수(

)가 압력에 비례하여 변화한다.In Equation 6, the fluid force is the poppet 200 displacement.

In proportion to , it can be regarded as a fluid spring acting in a direction to open the poppet 200, and the elastic modulus of the fluid spring (

) changes in proportion to the pressure.

를 유체 스프링의 탄성 계수

에 가깝게 설정할 수 있다면 포핏(200) 변위(

)와 밸브 유량(

)가 변화하더라도 압력(

)의 변화를 적게 할 수 있게 된다.In Equation 6, the elastic modulus of the spring

is the modulus of elasticity of the fluid spring

If it can be set close to the poppet (200) displacement (

) and valve flow (

) even if the pressure (

) is less likely to change.

As one of these methods, it is possible to consider a method to obtain a multi-step spring modulus close to that of a fluid spring according to the pressure range using several springs by improving the use of a single spring as in the existing pressure control valve. .

That is, the elastic modulus of the elastic part 400 is determined to correspond to the elastic modulus of the fluid spring acting in the direction of opening the poppet according to the pressure range using several springs.

A method of designing the spring formed in the elastic part 400 of the present invention in multiple stages will be described.

)를 결정하고, 각 단의 스프링 탄성을 결정하기 위한 압력(

)을 선정한다.First, the number of steps to divide the applied pressure range of the valve (

) and the pressure (

) is selected.

)에 대하여 대응하는 스프링의 탄성을 다음의 수학식 7로 계산한다.Design reference pressure of each stage (

), the elasticity of the corresponding spring is calculated by Equation 7 below.

: 각 단의 스프링 탄성 계수,

: 안전율,

: 유량 계수,

: 가압홈(210) 내부 지름,

: 각 단의 설계 기준 압력)(

: spring elastic modulus of each stage,

: safety factor,

: flow coefficient,

: the inner diameter of the pressing groove 210,

: Design standard pressure of each stage)

는 설계의 부정확성 등으로 유체력이 스프링력보다 더 큰 경우가 발생한다면 포핏(200)이 활짝 열리게 되는 불안정 현상을 방지하기 위한 안전율으로서 1.1~1.3 정도의 값으로 고려한다.here

is considered as a safety factor of about 1.1 to 1.3 as a safety factor to prevent an unstable phenomenon in which the poppet 200 is wide open if a case occurs where the fluid force is greater than the spring force due to design inaccuracy or the like.

)만큼의 스프링이 하우징(100) 내부에 설치되며, 한 단계 낮은 압력단의 등가 스프링에 현재 단의 스프링이 병렬로 작동한다.Number of split steps (

) as many springs are installed inside the housing 100 , and the spring of the current stage operates in parallel to the equivalent spring of the lower pressure stage.

That is, the equivalent elastic modulus of the current stage is obtained by adding the spring elastic modulus of the current stage to the equivalent spring elastic modulus of the lower pressure stage by the following equation.

:

번째 압력단의 단 번호,

:

번째 단의 등가 스프링 탄성 계수,

:

번째 단의 등가 스프링 탄성 계수,

번째 압력 단에서 작동하기 시작하는 스프링 탄성 계수)(

:

stage number of the second pressure stage,

:

equivalent spring modulus of the second stage,

:

equivalent spring modulus of the second stage,

spring modulus of elasticity starting to act in the second pressure stage)

에 대한 선경

, 스프링의 직경

, 유효 권선수

등의 형상 수치와 스프링 재료의 물성치인 횡탄성계수

를 결정하거나 선택한다. 적용되는 관계식은 수학식 9로 주어진다.spring elasticity of each stage

tribute to

, the diameter of the spring

, effective number of turns

The shape of the back and the modulus of lateral elasticity, which is the physical property of the spring material.

decide or choose The applied relation is given by Equation (9).

: 각 단의 스프링 탄성,

: 각 단의 스프링 탄성에 대한 선경,

: 스프링의 직경,

: 유효 권선수,

: 횡탄성계수)(

: spring elasticity of each stage,

: Wire diameter for spring elasticity of each stage,

: diameter of spring,

: effective number of turns,

: Transverse modulus)

, 스프링의 직경

, 권선수

등의 형상 수치와 스프링 재료의 물성치인 허용응력

에 대하여 수학식 10의 조건을 만족 여부를 검토하는 안전성 검토를 수행하고, 불만족한 경우에는 수학식 9를 다시 적용한다.Wire diameter of spring determined at each stage

, the diameter of the spring

, number of windings

Allowable stress, which is the shape value of the back and the physical property of the spring material

, a safety review is performed to examine whether the condition of Equation 10 is satisfied, and if not satisfied, Equation 9 is applied again.

: 와알 수정 계수,

: 스프링 나선 직경,

: 스프링의 선경,

: 각 단의 설계 기준 압력,

: 가압홈(210) 면적,

: 허용응력)(

: waal correction coefficient,

: spring spiral diameter,

: wire diameter of spring,

: Design standard pressure of each stage,

: Pressing groove 210 area,

: allowable stress)

: 와알 수정 계수,

: 스프링 지수)(

: waal correction coefficient,

: spring index)

: 스프링 지수,

: 스프링 나선 직경,

: 스프링의 선경)(

: spring index,

: spring spiral diameter,

: Wire diameter of spring)

)를 수학식 13으로부터 결정한다.Displacement (

) is determined from Equation (13).

: 각 단의 압력 범위에 대응하는 변위,

: 각 단의 설계 기준 압력,

: 가압홈(210) 면적,

:

번째 단의 등가 스프링 탄성 계수)(

: Displacement corresponding to the pressure range of each stage,

: Design standard pressure of each stage,

: Pressing groove 210 area,

:

equivalent spring modulus of the second stage)

의 스프링의 자유 길이(

)를 수학식 14를 이용하여 결정한다. Elasticity of each stage

free length of the spring (

) is determined using Equation 14.

: 각 단의 스프링의 자유 길이,

적절한 피치로 스프링 자유 길이 선택,

: 각 단의 압력 범위에 대응하는 변위)(

: the free length of the spring at each stage,

Selection of spring free length with appropriate pitch;

: Displacement corresponding to the pressure range of each stage)

의 스프링의 피치(

)를 수학식 15를 이용하여 결정한다.Elasticity of each stage

the pitch of the spring (

) is determined using Equation 15.

: 각 단의 스프링 피치,

: 각 단의 스프링의 자유 길이,

: 권선수)(

: Spring pitch of each stage,

: the free length of the spring at each stage,

: number of windings)

After selecting 70 bar (1bar = 100,000 N/m2), 140 bar, and 210 bar as three design reference pressures, the design values of the springs designed according to the design method above are given in Tables 1 and 2 below.

In addition, an experiment (computer simulation) was performed on the control precision of the pressure control valve to which the three-stage spring applied as given in Tables 1 and 2 was performed using a computer, and the simulation was programmed in MATLAB language.

10 is a graph showing the correlation between the elastic modulus of the spring and the elastic modulus of the fluid force of the multi-stage spring pressure control valve capable of precise pressure control according to the present invention.

)와 기존의 단일 스프링의 탄성 계수(

)뿐만 아니라 유체 스프링의 탄성(

)을 함께 표현하였다.As shown in Fig. 10, the effective elastic modulus of the three-stage spring (

) and the elastic modulus of the conventional single spring (

) as well as the elasticity of the fluid spring (

) are expressed together.

)은 스프링 변위가 작은 영역(낮은 압력 영역)에서는 유체 스프링의 탄성(

)과 차이가 매우 크다.The elasticity of the three-stage spring has a small difference from the elasticity of the so-called fluid spring at each stage, but compared to the elasticity of the existing single spring (

) is the elasticity ( ) of the fluid spring in the region where the spring displacement is small (low pressure region).

) is very different from

That is, in the first and second stage regions where the cracking pressure or set pressure of the pressure control valve composed of a three-stage spring is low, the spring force to close the poppet 200 and the fluid spring force to open the poppet 200 are similar, so that the pressure In contrast to the small change, in the conventional single spring pressure control valve, a large change in pressure will occur due to the difference between the spring force and the fluid spring force.

This change in pressure causes a greater increase in pressure together with the spring because fluid force is applied in the direction to close the poppet 200 in the valve having the structure shown in FIG. 1 .

11 is a graph showing the correlation of pressure according to the flow rate of the multi-stage spring pressure control valve capable of precise pressure control according to the present invention, and at the same time, the correlation between the pressure according to the flow rate of the multi-stage spring pressure control valve and the existing pressure of FIG. It is a graph comparing the pressure-flow correlation between the control valve and the improved pressure control valve of FIG. 2 .

11, the control precision of the pressure control valve composed of a three-stage spring, a single spring pressure control valve, and a poppet 200 as shown in FIG. 1 is closed by fluid force, respectively.

The control precision of the pressure control valve is that the pressure change with respect to the change of the flow rate is small.

11 shows the characteristics of the valve flow rate and pressure with respect to the opening amount of the poppet 200 of 0 to 0.68 mm.

In the pressure region where the set pressure (or cracking pressure) of the valve is 50 bar, the pressure rise of the three-stage spring valve is very low about 5 bar, whereas the pressure of the existing single spring valve rises significantly about 20 bar. In the valve of the structure in which the poppet 200 is closed by the fluid force as shown in FIG. 1, the pressure increased tremendously to close to 40 bar.

When the valve set pressure (or cracking pressure) is 100 bar, the difference between the pressure rise of the three-stage spring valve and the pressure rise of the single spring valve is reduced in the second-stage intermediate pressure region, but the difference is still about 10 bar.

However, in the valve having a structure in which the poppet 200 is closed by fluid force as shown in FIG. 1 , the pressure rises close to 50 bar.

It can be seen that the pressure rise of the three-stage spring valve and the pressure rise of the single spring valve are exactly the same, and the quantitative pressure rise is also small in the pressure region where the set pressure (or cracking pressure) of the valve is 150 bar, which is three steps higher.

This is because the equivalent elasticity of the three-stage spring and the elasticity of the existing single spring are set to be the same.

In a valve having a structure in which the poppet 200 is closed by a fluid force as shown in FIG. 1 , although the spring elasticity is set to be the same, there is still a very large pressure rise.

As described above, according to the multi-stage spring pressure control valve capable of precise pressure control according to the present invention, the difference between the elastic force of the spring and the fluid force generated while the fluid flows is reduced to precisely control the pressure control of the hydraulic circuit or mechanism. And, by determining the elastic force of the spring according to the fluid force generated while the fluid flows, there is an effect of reducing the error pressure generated by the fluid force.

As described above, the present invention has been mainly described with reference to preferred embodiments, but those of ordinary skill in the art to which the present invention pertains may vary the present invention within the scope not departing from the technical spirit and scope described in the claims of the present invention. It can be modified or modified in any way. Accordingly, the scope of the present invention should be construed by the appended claims including examples of many such modifications.

10: housing 11: poppet
12: spring 13: inlet
14: outlet

100: housing 110: inlet
120: outlet 200: poppet
210: pressing groove 220: first inclined surface
300: guide pipe 310: second inclined surface
400: elastic part 410: first spring
420: second spring 430: third spring
500: pressing end 510: fixing groove
600: adjusting screw

Claims (7)

a housing having an inlet and an outlet for supplying and discharging the fluid, and having a hollow interior to accommodate various members and fluids;
an induction pipe formed inside the housing and discharging the fluid introduced through the inlet in a set direction;
a poppet formed on the upper end of the guide tube and opened and closed while being spaced apart from the guide tube according to the pressure of the incoming fluid to discharge the fluid;
and an elastic part formed inside the housing and having springs formed in multiple stages so that one end presses the poppet toward the guide tube to prevent the fluid from being discharged from the guide tube;
The poppet further includes a pressure groove in which the pressure of the fluid is applied to the center of the lower end so as to be spaced apart from the guide tube by the pressure of the fluid flowing from the guide tube,
The pressing groove is formed with a first inclined surface whose diameter gradually decreases as it enters the poppet,
The upper edge of the guide tube is formed with a second inclined surface inclined to be in close contact with the first inclined surface,
When the poppet is spaced apart from the guide tube by the pressure of the fluid, the fluid flows between the first inclined surface and the second inclined surface in a downward direction between the poppet and the guide tube, so that the fluid force generated by the flow of the fluid is the Inducing the poppet to act in the opening direction,
a pressing end formed inside the housing and formed to support the other end of the multi-stage spring;
An adjustment screw having one end connected to the pressing end and the other end formed outside the housing to move the pressing end toward the poppet according to the rotational direction to adjust the elastic force of the elastic part;
The elastic part consists of a first spring, a second spring, and a third spring having different lengths,
When the pressure of the first spring, the second spring, and the third spring is increased according to the flow of the flowing fluid, the pressure generated by the flow of the fluid is reduced while sequentially contacting the poppet, and the fluid is discharged under a constant pressure. make it possible,
The elastic portion of the elastic portion according to the elastic modulus of the fluid force spring fluctuates by the pressure of the fluid by sequentially compressing the first spring, the second spring, and the third spring formed in multiple stages by the adjusting screw. characterized in that the coefficient can be adjusted
Multi-stage spring pressure control valve capable of precise pressure control.
delete The method of claim 1,
The pressing end further includes a plurality of fixing grooves that are cut in a circle in an inner direction to support the multi-stage spring of the elastic part,
The fixing groove is characterized in that it fixes the position of the spring in a no-load state that is not in contact with the poppet among the multi-stage springs.
Multi-stage spring pressure control valve capable of precise pressure control. delete delete delete delete

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