CN115467996A

CN115467996A - High-pressure switching valve head and high-pressure switching valve

Info

Publication number: CN115467996A
Application number: CN202210903068.5A
Authority: CN
Inventors: 陈伟雄
Original assignee: Xiamen Egux Fluid Control Equipment Co ltd
Current assignee: Xiamen Egux Fluid Control Equipment Co ltd
Priority date: 2022-07-29
Filing date: 2022-07-29
Publication date: 2022-12-13

Abstract

The invention provides a high-pressure switching valve head, which comprises a body and an upper cover, wherein a rotor and a stator are arranged between the body and the upper cover, the upper cover is provided with at least two channels, the stator is fixed on the upper cover and is provided with a through hole which is matched and communicated with the channels, the rotor is provided with at least one communicating groove, and each communicating groove is suitable for communicating two adjacent channels; the valve core shaft is arranged in the body, connected with the rotor and used for driving the rotor to rotate; the rotor and the stator are made of 30% of polyether-ether-ketone, 60% of polytetrafluoroethylene and 10% of polyimide in a composite mode, and the friction force between the rotor and the stator is smaller than 1.5N when the rotor and the stator rotate. The invention also provides a high-pressure switching valve. Through the scheme, the high-pressure switching valve is smaller in size and faster in switching speed.

Description

High-pressure switching valve head and high-pressure switching valve

Technical Field

The invention relates to the technical field of switching valves, in particular to a high-pressure switching valve head and a high-pressure switching valve.

Background

The switching valve is a switching device commonly used in fluid equipment, and is widely applied to an analysis instrument or a detection instrument, wherein the volume of the switching valve is required to be as small as possible and the switching speed is as high as possible, but the rotor and the stator of the existing high-pressure switching valve are both made of ceramic or sapphire materials, but when the two materials are adopted, the planes are required to be ground to be smooth and flat for sealing, so when the two flat planes are adhered together, air in the middle is extruded out, a vacuum layer is formed in the middle, if the two parts are required to be separated, a large torque is required for rotating, and when the suction force is larger than the rotating torque, the rotor or the stator can be broken, so that the product fails; the larger rotating torque force also needs the larger stepping motor to drive, if the smaller 42 stepping motor is adopted, the rotor cannot be driven to rotate, not to mention that the faster switching speed is achieved, and the larger motor can cause the volume of the whole switching valve to become larger, so that the requirement of an analysis instrument is difficult to meet.

Disclosure of Invention

The invention discloses a high-pressure switching valve head, aiming at solving the problems of larger volume and insufficient switching speed of the existing high-pressure switching valve.

The invention provides a high-pressure switching valve head, which comprises a body and an upper cover, wherein a rotor and a stator are arranged between the body and the upper cover, the upper cover is provided with at least two channels, the stator is fixed on the upper cover and is provided with a through hole matched and communicated with the channels, the rotor is provided with at least one communicating groove, and each communicating groove is suitable for communicating two adjacent channels; the valve core shaft is arranged in the body, connected with the rotor and used for driving the rotor to rotate; the rotor and the stator are made of 30% of polyether-ether-ketone, 60% of polytetrafluoroethylene and 10% of polyimide in a composite mode, and the friction force between the rotor and the stator is smaller than 1.5N when the rotor and the stator rotate.

Further, the rotor and the stator are manufactured in the following manner: according to the mass ratio, 3 parts of polyether-ether-ketone, 6 parts of polytetrafluoroethylene and 1 part of polyimide are placed in a mixer to be fully mixed and dried; heating the oven to 100-120 ℃ and baking for 2-4 hours to finally obtain material powder; the powder is put into a granulator and heated to 350-360 ℃, the granular material is extruded for standby, and the granular material is put into an injection molding machine and heated to 350-360 ℃ and extruded into a die cavity.

Furthermore, the friction coefficient between the rotor and the stator is 0.05-0.1.

Furthermore, six channels are uniformly arranged on the upper cover around the circumference and are respectively defined as a first channel, a second channel, a third channel, a fourth channel, a fifth channel and a sixth channel according to the circumferential sequence, wherein the first channel is communicated with the fourth channel through a quantitative ring; the rotor is uniformly provided with three arc-shaped communicating grooves around the circumference, the three arc-shaped communicating grooves are defined as a first communicating groove, a first communicating groove and a first communicating groove, and the communicating grooves are suitable for enabling one channel to be switched and communicated with any one of two adjacent channels under the driving of the valve core shaft.

Further, the valve core shaft is an integrated valve core.

Further, the valve core shaft is connected to the body through a bearing, and a butterfly spring is arranged between the valve core shaft and the bearing and is suitable for pushing the valve core axially and tightly.

Further, the belleville spring is overlapped through five single sheets and is overlapped in a mode that the front side and the back side are staggered.

The invention also provides a high-pressure switching valve which comprises the high-pressure switching valve head, wherein the bottom of the valve core shaft of the high-pressure switching valve head is connected with a stepping motor.

Further, the stepping motor is a 42 stepping motor.

Further, a speed reducing mechanism is arranged between the stepping motor and the valve core shaft.

Has the advantages that:

the novel composite material is prepared by adopting a novel formula and a novel process, the wear resistance and the friction coefficient of the composite material are lower, the friction coefficient between the rotor and the stator can be reduced by the rotor and stator materials prepared from the composite material, the friction force can be further reduced under the same load, and the service life is longer. Meanwhile, the friction force between the rotor and the stator can be reduced due to the reduction of the friction coefficient, so that the rotor can be driven to rotate by using a smaller stepping motor, and the volume of the whole switching valve can be reduced to meet the requirement of a compact analysis instrument. Furthermore, through the superposition arrangement of the belleville springs, the load of the belleville springs on the rotor and the stator is stable, and the problem that the small stepping motor cannot drive the rotor to rotate due to large load change is effectively solved.

Drawings

Fig. 1 is a schematic structural diagram of a high-pressure switching valve according to an embodiment of the present invention;

FIG. 2 is a schematic cross-sectional view of the structure of FIG. 1;

FIG. 3 is a schematic structural diagram of a high-pressure switching valve head of a high-pressure switching valve according to an embodiment of the present invention;

FIG. 4 is a schematic cross-sectional view of FIG. 3;

FIG. 5 is a schematic structural diagram of a rotor of a high pressure switching valve according to an embodiment of the present invention;

FIG. 6 is a schematic structural diagram of a stator of a high pressure switching valve according to an embodiment of the present invention;

FIG. 7 is a schematic illustration of a loading state of the high pressure switching valve during operation according to an embodiment of the present invention;

FIG. 8 is a schematic diagram of a sample injection state of the high-pressure switching valve during operation according to an embodiment of the present invention;

FIG. 9 is a schematic structural diagram illustrating a stacked state of the belleville springs of the high pressure switching valve according to the embodiment of the present invention;

FIG. 10 is a graph of experimental data for the characteristics of a belleville spring after folding;

FIG. 11 is another graph of experimental data for the behavior of a belleville spring after folding;

icon: the motor comprises an upper cover 10, a channel 11, a first channel 111, a second channel 112, a third channel 113, a fourth channel 114, a fifth channel 115, a sixth channel 116, a body 20, a stator 30, a through hole 31, a rotor 40, a communication groove 41, a first communication groove 411, a second communication groove 412, a third communication groove 413, a belleville spring 50, a valve core shaft 60, a bearing 70, a snap spring 80, a housing 90, an encoder 100, a coupler 110, a stepping motor 120, a circuit board 130, a fixing pin 140, a knurled pin 150 and a dosing ring 160.

Detailed Description

Examples

Referring to fig. 1 to 2, an embodiment of the present invention provides a high-pressure switching valve, which includes a high-pressure switching valve head, and a stepping motor 120 is connected to a bottom of the valve core shaft 60. For the application in a precise analysis instrument, the stepping motor 120 is the smallest 42 stepping motor 120, and the maximum rotation torque is 1.5N.

As shown in fig. 3 to 6, the high pressure switching valve head described above includes a body 20 and an upper cover 10, a rotor 40 and a stator 30 are disposed between the body 20 and the upper cover 10, the upper cover 10 is provided with at least two channels 11, the stator 30 is fixed on the upper cover 10 and is provided with a through hole 31 in matching communication with the channels 11, the rotor 40 is provided with at least one communication groove 41, and each communication groove 41 is adapted to communicate with two adjacent channels 11; the valve core shaft 60 is arranged in the body 20, connected with the rotor 40 and used for driving the rotor 40 to rotate; the rotor 40 and the stator 30 are made of novel composite materials, and the friction force between the rotor 40 and the stator 30 is less than 1.5N when the rotor 40 and the stator rotate.

In this embodiment, the switching head includes an upper cover 10, a stator 30, a rotor 40, a disc spring, a body 20, a valve core shaft 60, a bearing 70, a snap spring 80 and a pin, wherein the upper cover 10 and the body 20 are fixedly connected by a screw, the stator 30 is disposed at the bottom of the upper cover 10 and is fixed by a fixing pin 140 to prevent rotation thereof, and a through hole 31 on the stator 30 is fixedly communicated with a channel 11 of the upper cover 10; the rotor 40 is arranged below the stator 30 and is in sealed connection with the stator 30, the lower part of the rotor 40 is connected to the valve core shaft 60 and can be driven by the valve core shaft 60 to rotate, and the rotor 40 is connected with the valve core shaft 60 through a pin; the communication groove 41 is provided on a surface of the rotor 40 connected to the stator 30, and the communication groove 41 communicates two adjacent passages 11. The valve core shaft 60 is an integrated valve core shaft 60, namely, the integrated valve core shaft is integrally formed, and compared with the existing split type valve core shaft, the integrated valve core shaft can reduce rotation errors and transmission time difference when rotating, so that the rotating speed is faster. The spool shaft 60 is connected with the body 20 through a bearing 70 to reduce the rotation resistance, and the two bearings 70 are provided, and a flat thrust ball bearing 70 and a micro deep groove bearing 70 are respectively used, so that the friction resistance is smaller. One end of the valve core shaft 60 extends out of the body 20, a clamp spring 80 is arranged at the extending position for limiting, and a knurled pin 150 is connected to the end of the valve core shaft 60 extending out of the body 20 and used for being connected with a driving mechanism.

In order to meet the use requirements of the rotor 40 and the stator 30 in the invention, the present embodiment provides a composite material, the formula and the manufacturing process of the composite material can be used for manufacturing the rotor 40 and the stator 30, the formula comprises 30% of polyether-ether-ketone, 60% of polytetrafluoroethylene and 10% of polyimide, and the composite material has both polyimide and polyether-ether-ketone high temperature resistance and polytetrafluoroethylene self-lubricity; the manufacturing process comprises the following steps: according to the mass, 3 parts of polyether-ether-ketone, 6 parts of polytetrafluoroethylene and 1 part of polyimide are placed in a mixer to be fully mixed and dried, and an oven is heated to the temperature range of 100-120 ℃ to be baked for 2-4 hours, so that material powder is finally obtained; the powder is put into a granulator and heated to 350-360 ℃, the granular material is extruded for standby, the granular material is put into an injection molding machine and heated to 350-360 ℃, the granular material is extruded into a mold cavity to obtain the required stator 30 and rotor 40, and the required stator 30 and rotor 40 are ground to a mirror surface through high-precision plane grinding, so that the friction coefficient reaches 0.05-0.1.

In the embodiment, a new composite material can be obtained by mixing and processing the polyetheretherketone, the polytetrafluoroethylene and the polyimide, and the compounded new material has higher wear resistance and heat resistance and simultaneously reduces the friction coefficient, wherein the friction coefficient of the rotor 40 and the stator 30 can reach 0.05-0.1 after being ground to a mirror surface, so the composite material is more suitable for being used as a material of the rotor 40 and the stator 30. The rotor 40 and the stator 30 made of the composite material are suitable for working in an environment with concentrated sulfuric acid and are suitable for water quality detection equipment, and the service life of the water quality is not influenced by the cleanliness of water quality. Experimental data for this composite is provided in table 1 below.

TABLE 1

In the present embodiment, as shown in fig. 7 and fig. 8, the number of the channels 11 and the number of the communication grooves 41 of the upper cover 10 may be provided with a plurality of schemes, here, taking a two-position six-way analysis valve scheme as an example, the number of the channels 11 is uniformly six around the circumference on the upper cover 10, and the six channels are respectively defined as a first channel 111, a second channel 112, a third channel 113, a fourth channel 114, a fifth channel 115 and a sixth channel 116 in the circumferential sequence, wherein the first channel 111 and the fourth channel 114 are communicated through a dosing ring 160; three arc-shaped communication grooves 41 are uniformly arranged on the rotor 40 around the circumference, which are defined as a first communication groove 411, a second communication groove 412 and a third communication groove 413, and the communication grooves 41 are adapted to make one of the two channels 11 adjacent to the channel 11 switch and communicate with each other under the driving of the valve core shaft 60. Here, the fifth channel 115 is connected to a high pressure pump, the second channel 112 is a liquid inlet end, the third channel 113 is a liquid outlet end, and the sixth channel 116 is connected to the chromatographic column for analysis. In this scheme, the valve head can switch in loading state and two kinds of states of appearance state, accomplishes different work content. In a loading state, the first connecting groove 411 is communicated with the first channel 111 and the second channel 112, the second connecting groove 412 is communicated with the third channel 113 and the fourth channel 114, the third connecting groove 413 is communicated with the fifth channel 115 and the sixth channel 116, at this time, liquid to be analyzed enters from the second channel 112 and flows out from the first channel 111, then is conveyed from the first channel 111 to the fourth channel 114 through the quantitative ring 160, and flows out from the third channel 113; at this time, the fifth passage 115 and the sixth passage 116 are in a communicated state, but the high-pressure pump is not started; when the quantitative ring 160 is filled with liquid, the rotor 40 is rotated and switched to a sample introduction state under the action of the valve core shaft 60, at this time, the first connecting groove is communicated with the first channel 111 and the sixth channel 116, the second connecting groove is communicated with the second channel 112 and the third channel 113, the third connecting groove is communicated with the fourth channel 114 and the fifth channel 115, the high-pressure pump is started, the analysis liquid in the quantitative ring 160 is pushed into the chromatographic column from the sixth channel 116 by the pressure of the high-pressure pump for analysis, and then the rotating shaft is reversely driven and switched to a loading state. Through this scheme for when carrying out liquid or gas analysis, can load fast and advance the appearance, and the volume of advancing the appearance the same at every turn, conveniently carry out chromatography. In this embodiment, the liquid in the quantitative ring 160 can maintain a certain amount of liquid when the quantitative ring is switched to the sample injection state after loading, and the switching time between loading and sample injection is short. Here, the dosing ring 160 is a prior art product and will not be described in detail.

As shown in fig. 9, a belleville spring 50 is disposed on the spool shaft 60, and the belleville spring 50 is disposed in the body 20 and is used for pressing the spool shaft 60 upwards, so that a certain pressure is maintained between the rotor 40 and the stator 30, and a sealing effect is achieved. Five pieces are arranged for the belleville spring 50, the five pieces are overlapped to form one spring, the load of the belleville spring 50 after being pressed is 0-929N, and the load can be controlled by adjusting the deformation amount. The characteristics of the stacked belleville springs 50 are shown in the experimental data of fig. 10 and 11, wherein five belleville springs 50 are stacked in a "forward-reverse-forward" manner, but not in the same direction, so that the magnitude of the elastic force of the belleville springs 50 can be conveniently controlled and adjusted, and compared with a single belleville spring 50, the stacked belleville springs 50 have the advantages that the deformation amount generated by the stacked manner is larger under the condition that the loads applied to the rotor 40 by the belleville springs 50 are the same, that is, under the deformation amount within a larger range, the load change of the stacked belleville springs 50 to the rotor 40 is smaller, so that the stability of the load between the rotor 40 and the stator 30 can be improved. Here, the valve plug shaft 60 needs to be tightly pressed against the rotor 40 and the stator 30 through the elastic force of the belleville spring 50 to keep the sealing between the rotor 40 and the stator 30, and meanwhile, the friction force between the rotor 40 and the stator 30 is smaller than 1.5N, the friction force between the rotor 40 and the stator 30 is the friction force between the rotor 40 and the stator 30, and since the friction coefficient is 0.05-0.1, namely, the load of the belleville spring 50 on the rotor 40 is 3N-15N, a high load value can be stably achieved through the overlapped belleville spring 50. Under the load, it is ensured 42 that the stepping motor 120 can smoothly drive the rotor 40 to rotate, so as to achieve the effect of smooth switching. In the conventional belleville spring 50, as can be seen from table 3, if the deformation amount of the single belleville spring 50 is slightly changed, the load becomes large, which is not favorable for maintaining a proper friction force between the rotor 40 and the stator 30, so that the stepping motor 120 cannot drive the rotor 40 to rotate under a small deformation amount 42.

In this embodiment, the driving portion of the high-pressure switching valve is further provided with an encoder 100, a coupler 110, a housing 90 and a circuit board 130, the circuit board 130 is connected to a stepping motor 120, the stepping motor 120 is connected to the valve core shaft 60 through the coupler 110, and the circuit board 130 is provided with a single chip microcomputer, and the single chip microcomputer controls the stepping motor 120 to rotate by a certain angle, for example, the two-position six-way switching valve rotates by 60 degrees each time, so that the switching valve is rapidly switched between the loading state and the sample injection state. Here, by providing the integrated spool shaft 60 and superposing the belleville springs 50, the switching speed can be up to 100ms or less and the pressure resistance can be up to 60MPA in cooperation with the rotor 40 and the stator 30 which are made of new composite materials.

In another preferred embodiment, a speed reducing mechanism is further disposed between the stepping motor 120 and the valve plug shaft 60, the speed reducing mechanism can use a gear transmission mechanism, and a speed reducing effect is achieved through a gear rotation ratio, wherein the speed reducing ratio can reach 1:4, so that the switching speed is faster.

In the invention, the stator 30 and the rotor 40 are switched, so that when the rotor 40 and the stator 30 are damaged, the function can be recovered by replacing the rotor 40 and the stator 30, and in the existing switching valve, only the rotor 40 is arranged, when the rotor 40 rotates, the upper cover 10 is easily worn, the upper cover 10 is damaged, even the sealing performance is damaged, and only the whole switching can be carried out, therefore, the scheme of the invention can greatly reduce the cost.

It should be understood that: the above is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above-mentioned embodiments, and all technical solutions belonging to the idea of the present invention belong to the protection scope of the present invention.

The above description of the drawings used in the embodiments shows only some examples of the invention and should not be taken as limiting the scope, from which other relevant drawings can be derived by a person skilled in the art without inventive step.

Claims

1. A high-pressure switching valve head comprises a body and an upper cover, wherein a rotor and a stator are arranged between the body and the upper cover, the upper cover is provided with at least two channels, the stator is fixed on the upper cover and is provided with a through hole which is matched and communicated with the channels, the rotor is provided with at least one communicating groove, and each communicating groove is suitable for communicating two adjacent channels; the valve is characterized by further comprising a valve core shaft, wherein the valve core shaft is arranged in the body, is connected with the rotor and is used for driving the rotor to rotate; the rotor and the stator are made of 30% of polyether-ether-ketone, 60% of polytetrafluoroethylene and 10% of polyimide in a composite mode, and the friction force between the rotor and the stator is smaller than 1.5N when the rotor and the stator rotate.

2. The high pressure switching valve head according to claim 1, wherein the rotor and stator are fabricated by: according to the mass ratio, 6 parts of polytetrafluoroethylene and 1 part of polyimide are respectively placed in a mixer for full mixing and drying after 3 parts of polyether-ether-ketone; heating the oven to 100-120 ℃ and baking for 2-4 hours to finally obtain material powder; the powder is put into a granulator and heated to 350-360 ℃, the granular material is extruded for standby, and the granular material is put into an injection molding machine and heated to 350-360 ℃ and extruded into a die cavity.

3. The high pressure switching valve head according to claim 1, wherein the coefficient of friction between the rotor and the stator is between 0.05 and 0.1.

4. The high-pressure switching valve head according to claim 1, wherein six channels are uniformly arranged on the upper cover around the circumference, and are respectively defined as a first channel, a second channel, a third channel, a fourth channel, a fifth channel and a sixth channel according to the circumferential sequence, wherein the first channel and the fourth channel are communicated through a quantitative ring; the rotor is uniformly provided with three arc-shaped communicating grooves around the circumference, the three arc-shaped communicating grooves are defined as a first communicating groove, a first communicating groove and a first communicating groove, and the communicating grooves are suitable for enabling one channel to be switched and communicated with any one of two adjacent channels under the driving of the valve core shaft.

5. The high pressure switch valve head according to claim 4, wherein the valve spool shaft is a one-piece valve spool.

6. The high pressure switching valve head according to claim 5, wherein the spool shaft is connected to the body through a bearing, and a belleville spring is disposed between the spool shaft and the bearing, the belleville spring being adapted to axially urge the spool.

7. The high pressure switch valve head according to claim 6, wherein said belleville springs are stacked by five single sheets, and stacked in a front-to-back staggered manner.

8. A high pressure switching valve, comprising the high pressure switching valve head according to any one of claims 1 to 7, wherein a stepping motor is connected to the bottom of the valve core shaft of the high pressure switching valve head.

9. The high pressure switching valve of claim 8, wherein the stepper motor is a 42 stepper motor.

10. The high-pressure switching valve according to claim 9, wherein a speed reduction mechanism is provided between the stepping motor and the spool shaft.