valve

Abstract

The present invention provides a valve, comprising a valve body, wherein a lower valve stem and an upper valve stem inserted on the upper part of the lower valve stem are accommodated inside the valve body, a quantitative ring is sleeved at the insertion position of the upper valve stem and the lower valve stem, the valve body and the quantitative ring are made of PBT material, and when a medicinal solution contains ethanol, the amount of formaldehyde decomposed when the valve contacts the medicinal solution can be significantly reduced, thereby avoiding the problem of excessive formaldehyde endangering the health of users.

Description

Technical Field

[0001] The invention relates to a valve, in particular to a valve containing PBT material. Background Art

[0002] The valve body, metering ring and upper and lower valve stems of existing aerosol valves are mostly made of POM, which is a polymer obtained by polymerization of formaldehyde. These parts will come into contact with the liquid medicine during the use of the product. When such valves are used for liquid medicine containing ethanol, formaldehyde is easily decomposed from POM and enters the liquid medicine, endangering the health of users. Summary of the invention

[0003] In order to overcome the defects of the prior art, the present invention provides a valve with stable constituent materials and healthier for users.

[0004] The technical solution adopted by the present invention to solve the problems of the prior art is:

[0005] A valve comprises a valve body, wherein a lower valve stem and an upper valve stem inserted on the upper part of the lower valve stem are accommodated inside the valve body, a quantitative ring is sleeved at the insertion place of the upper valve stem and the lower valve stem, and the valve body and the quantitative ring are made of PBT material.

[0006] In one of the embodiments, the valve further comprises an outer sleeve, the valve body is at least partially sleeved in the outer sleeve, a gasket sleeved on the valve body is arranged inside the outer sleeve, a spring is arranged between the lower valve stem and the valve body, an upper valve stem gasket and a lower valve stem gasket are respectively arranged on the upper and lower end faces of the metering ring, the lower surface of the lower valve stem gasket contacts the valve body, the upper surface of the upper valve stem gasket contacts the outer sleeve, the outer sleeve has a hole, and the upper valve stem passes through the outer sleeve through the hole.

[0007] In one embodiment, the ratio of the weight of the valve body and the metering ring to the weight of the valve is in a range of 34.7% to 42.4%, wherein the weight of the valve is the total weight of the valve minus the weight of the outer sleeve.

[0008] In one embodiment, the weight range of the valve body and the quantitative ring is 0.493±0.026g.

[0009] In one embodiment, the weight range of the valve is 1.286±0.065 g.

[0010] In one embodiment, the weight of the valve body is 0.38 g and the weight of the quantitative ring is 0.113 g.

[0011] In one embodiment, the weight of the valve body is 0.4 g and the weight of the quantitative ring is 0.119 g.

[0012] In one embodiment, the weight of the valve body is 0.36 g and the weight of the quantitative ring is 0.107 g.

[0013] In one of the embodiments, the valve further comprises a POM material, and a ratio of a weight of the POM material to a weight of the valve is no greater than 18.8%.

[0014] Compared with the prior art, the valve body and the quantitative ring of the valve provided by the present invention are made of PBT material. When the liquid medicine contains ethanol, the content of formaldehyde decomposed by the valve can be significantly reduced, thereby avoiding harm to the health of users.

[0015] The present invention also provides an injection molding method for injection molding PBT raw materials into the above-mentioned valve body and metering ring, the injection molding method includes raw material drying, screw pre-molding and injection molding; during the raw material drying process, the raw material needs to be dried at a temperature of 60-80 degrees for 4-5 hours; during the screw pre-molding process, the ratio of the feeding section, the compression section and the metering section is 1:1:1, the material temperature range is 240-270 degrees, and the material stays in the screw for no more than 15 minutes; during the injection molding process, the mold temperature range is 50-80 degrees, the material stays in the hot runner for no more than 3 minutes, the hot runner temperature is 240-270 degrees, the injection pressure range is 1000-1400bar, the holding pressure is set at 50%-70% of the injection pressure, the back pressure is 5-100bar, and the cooling time is 5-8 seconds.

[0016] Compared with the prior art, the injection molding method of the present invention improves the quality of injection molded parts. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The objectives, technical solutions and beneficial effects of the invention described above can be achieved through the following drawings:

[0018] Figure 1 It is a cross-sectional view of the valve.

[0019] Figure 2 It is a flow chart of the injection molding method. DETAILED DESCRIPTION

[0020] like Figure 1The valve 100 in one embodiment shown is an aerosol valve, which can be an aerosol valve with an ultra-low extract formula, and is usually inserted at the opening of the container. The valve has a valve body 9, and the valve body 9 contains a lower valve stem 5 and an upper valve stem 1. The upper valve stem 1 is inserted into the upper part of the lower valve stem 5. A quantitative ring 3 is sleeved at the insertion point between the upper valve stem 1 and the lower valve stem 5, and a spring 8 is arranged between the lower valve stem 5 and the valve body 9. The valve 100 also has a jacket 7, and at least the upper part of the valve body 9 is sleeved in the jacket 7, and the material of the jacket 7 is usually metal. A gasket 6 sleeved on the valve body 9 is arranged inside the jacket 7, and the upper and lower end surfaces of the quantitative ring 3 are respectively provided with an upper valve stem gasket 2 and a lower valve stem gasket 4, the lower surface of the lower valve stem gasket 4 is in contact with the valve body 9, and the upper surface of the upper valve stem gasket 2 is in contact with the jacket 7. There is a hole on the jacket 7, and the upper valve stem 1 passes through the jacket 7. In the valve 100, the valve body 9 and the quantitative ring 3 are made of PBT material.

[0021] The Chinese name of PBT is polybutylene terephthalate. Compared with POM, PBT has better stability, is resistant to hot water, alkalis, acids, and oils, and will not decompose formaldehyde when in contact with ethanol. Therefore, when the liquid medicine contains ethanol, the valve body 9 and the quantitative ring 3 of the valve 100 are made of PBT material, which can significantly reduce the content of decomposed formaldehyde and avoid harming the health of users.

[0022] Among the various components of the above valve, the valve body 9 is used to accommodate the upper valve stem 2, the lower valve stem 5, the quantitative ring 3 and the spring 8. The quantitative ring 3 is sleeved at the joint of the upper valve stem 1 and the lower valve stem 5 to form a quantitative cavity for quantitatively dosing the aerosol. The lower valve stem 5 is a passage between the quantitative cavity and the container, and the upper valve stem 1 is a passage between the quantitative cavity and the outside world. The gasket 6, the upper valve stem gasket 2, and the lower valve stem gasket 4 are all used for sealing, and the spring 8 is used to reset the valve stem. The valve body 9 and the quantitative ring 3 are made of PBT material, the upper valve stem 1 and the lower valve stem 5 are made of POM material, the spring 8 is made of stainless steel, the gasket 6, the upper valve stem gasket 2 and the lower valve stem gasket 4 are made of EPDM material. The Chinese name of EPDM is ethylene propylene diene monomer rubber, which has the ability to resist oxidation, ozone and corrosion.

[0023] Preferably, the valve body 9 and the dosing ring 3 are made of PBT material, and the ratio of the weight of the valve body 9 and the dosing ring 3 to the weight of the valve 100 is in the range of 34.7% to 42.4%, wherein the weight of the valve is the total weight of the valve minus the weight of the outer jacket. The total weight of the valve includes the weight of the valve body 9, the upper valve stem 1, the lower valve stem 4, the dosing ring 3, the upper valve stem gasket 2, the lower valve stem gasket 4, the spring 8, the gasket 6 and the outer jacket 7, and the weight of the valve is the weight of the valve without the outer jacket 7, i.e., the weight of all the parts in Table 1.

[0024] Preferably, the weight range of the valve body 9 and the quantitative ring 3 is 0.493±0.026g. Preferably, the weight range of the valve 100 is 1.286±0.065g. Specifically, during the operation of the valve 100, among the parts in contact with the liquid medicine, the weight of the valve body 9 is 0.38±0.02g, the weight of the lower valve stem 5 is 0.094±0.005g, the weight of the upper valve stem 1 is 0.125±0.007g, the weight of the quantitative ring 3 is 0.113±0.006g, the weight of the lower valve stem gasket 4 is 0.025±0.002g, the weight of the upper valve stem gasket 2 is 0.044±0.003g, the weight of the spring 8 is 0.223±0.02g, and the weight of the gasket 6 is 0.282±0.02g.

[0025] Preferably, the valve 100 further comprises POM material, that is, also comprises parts made of POM material. The ratio of the weight of the POM material to the weight of the valve 100 is not greater than 18.8%, and preferably, the ratio of the weight of the POM material to the weight of the valve 100 ranges from 15.4% to 18.8%.

[0026] Preferably, the weight of the valve body 9 is 0.38g, and the weight of the quantitative ring 3 is 0.113g. As shown in Table 1, the weight ratio of the valve body 9 and the quantitative ring 3 to the weight of the valve 100 is 38.3%. The upper valve stem 1 and the lower valve stem 5 are made of POM material, and the weights are 0.125g and 0.094g respectively, so the weight ratio of the POM material to the weight of the valve 100 is 18%. The weight of the valve body 9 and the quantitative ring 3 accounts for a large proportion, so the valve body 9 and the quantitative ring 3 are made of PBT material, which can significantly reduce the amount of formaldehyde decomposed by each part of the valve 100 when it contacts ethanol, avoiding the problem of excessive formaldehyde endangering the health of users.

[0027] Table 1

[0028] Component Material effect weight Weight ratio Valve body PBT Accommodates upper and lower valve stems, dosing rings, and springs 0.38g 29.5％ Lower valve stem POM The channel between the metering chamber and the bottle 0.094g 7.3％ Upper valve stem POM Channel between quantitative cavity and the outside world 0.125g 9.7％ Quantitative ring PBT Quantification 0.113g 8.8％ Lower stem gasket EPDM seal 0.025g 1.9％ Upper stem gasket EPDM seal 0.044g 3.4％ spring Stainless steel Reset the valve stem 0.223g 17.3％ Bottle neck gasket EPDM seal 0.282g 21.9％

[0029] In another optional embodiment, the weight of the valve body 9 is 0.4g, and the weight of the dosing ring 3 is 0.119g. As shown in Table 2, the weight of the valve body 9 and the dosing ring 3 to the weight of the valve 100 is 40.2%, wherein the weight of the valve is the total weight of the valve minus the weight of the outer jacket. The total weight of the valve includes the weight of the valve body 9, the upper valve stem 1, the lower valve stem 4, the dosing ring 3, the upper valve stem gasket 2, the lower valve stem gasket 4, the spring 8, the gasket 6 and the outer jacket 7. The weight of the valve is the weight of the valve without the outer jacket 7, i.e., the weight of all parts in Table 2. The upper valve stem 1 and the lower valve stem 5 are made of POM material, and the weights are 0.118g and 0.089g respectively, so the weight ratio of the POM material to the weight of the valve 100 is 16%. The weight of the valve body 9 and the metering ring 3 accounts for a large proportion, so making the valve body 9 and the metering ring 3 with PBT material can significantly reduce the amount of formaldehyde decomposed when the various parts of the valve 100 come into contact with ethanol, avoiding the problem of excessive formaldehyde endangering the health of users.

[0030] Table 2

[0031]

[0032]

[0033] In another optional embodiment, the weight of the valve body 9 is 0.36g, and the weight of the dosing ring 3 is 0.107g. As shown in Table 3, the weight of the valve body 9 and the dosing ring 3 to the weight of the valve 100 is 35.4%, wherein the weight of the valve is the total weight of the valve minus the weight of the outer jacket. The total weight of the valve includes the weight of the valve body 9, the upper valve stem 1, the lower valve stem 4, the dosing ring 3, the upper valve stem gasket 2, the lower valve stem gasket 4, the spring 8, the gasket 6 and the outer jacket 7. The weight of the valve is the weight of the valve without the outer jacket 7, i.e., the weight of all parts in Table 3. The upper valve stem 1 and the lower valve stem 5 are made of POM material, and the weights are 0.132g and 0.099g respectively, so the weight ratio of the POM material to the weight of the valve 100 is 17.5%. The weight of the valve body 9 and the metering ring 3 accounts for a large proportion, so making the valve body 9 and the metering ring 3 with PBT material can significantly reduce the amount of formaldehyde decomposed when the various parts of the valve 100 come into contact with ethanol, avoiding the problem of excessive formaldehyde endangering the health of users.

[0034] Table 3

[0035]

[0036]

[0037] The present invention also provides an injection molding method for injection molding the PBT raw material into the valve body 9 and the metering ring 3 of the valve 100. The process of the injection molding method is as follows: Figure 2As shown. The injection molding method includes raw material drying, screw pre-molding and injection molding. At the beginning of injection molding, the raw materials need to be prepared first and then dried. During the raw material drying process, the raw materials need to be dried at a temperature of 60-80 degrees for 4-5 hours. This process can be carried out in a dehumidifying dryer. After drying, you can check whether the raw materials have reached the drying standard. If not, you need to dry the raw materials again.

[0038] When the raw material has reached the dry standard, it enters the screw pre-plasticization process. During the screw pre-plasticization process, the ratio of the feeding section, compression section and metering section is 1:1:1, and the material temperature ranges from 240-270 degrees. If it is lower than 240 degrees, PBT is easy to condense; if it is higher than 270 degrees, it is easy to produce thermal cracking. The material stays in the screw for no more than 15 minutes.

[0039] After the screw is pre-molded, the next step is injection molding. During the injection molding process, PBT is first injected into the mold. The temperature range of the mold is 50-80 degrees. The material stays in the hot runner for no more than 3 minutes. The hot runner temperature is 240-270 degrees, and the injection pressure range is 1000-1400bar. After the injection is completed, it is necessary to maintain the pressure. The holding pressure is set at 50%-70% of the injection pressure, the back pressure is 5-100bar, and then cool it down. The cooling time is 5-8 seconds. After cooling is completed, the molded material needs to be ejected from the mold and quality inspected. If the quality inspection is qualified, the material can be installed in the valve. If the quality inspection is unqualified, it will be scrapped. This injection molding method improves the quality of injection molded parts.

[0040] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0041] The above-mentioned embodiments only express the implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the invention patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the attached claims.

Claims

1. A valve having a valve body, wherein a lower valve stem and an upper valve stem inserted on the upper part of the lower valve stem are housed inside the valve body, and a quantitative ring is sleeved at the insertion point of the upper valve stem and the lower valve stem, characterized in that: The valve body and the quantitative ring are made of PBT material; the upper valve stem and the lower valve stem are made of POM material; The valve also has a jacket, the valve body is at least partially sleeved in the jacket, a gasket sleeved on the valve body is arranged inside the jacket, a spring is arranged between the lower valve stem and the valve body, an upper valve stem gasket and a lower valve stem gasket are respectively arranged on the upper and lower end surfaces of the quantitative ring, the lower surface of the lower valve stem gasket contacts the valve body, and the upper surface of the upper valve stem gasket contacts the jacket, the jacket has a hole, and the upper valve stem passes through the jacket through the hole; The ratio of the weight of the valve body and the quantitative ring to the weight of the valve is in a range of 34.7% to 42.4%, wherein the weight of the valve is the total weight of the valve minus the weight of the outer sleeve.

2. The valve according to claim 1, characterized in that: The weight range of the valve body and the quantitative ring is 0.493±0.026g.

3. The valve according to claim 1, characterized in that: The weight range of the valve is 1.286±0.065g.

4. The valve according to claim 2, characterized in that: The weight of the valve body is 0.38 g, and the weight of the quantitative ring is 0.113 g.

5. The valve according to claim 2, characterized in that: The weight of the valve body is 0.4 g, and the weight of the quantitative ring is 0.119 g.

6. The valve according to claim 2, characterized in that: The weight of the valve body is 0.36g, and the weight of the quantitative ring is 0.107g.

7. The valve according to claim 1, characterized in that The ratio of the weight of the POM material to the weight of the valve is no more than 18.8%.

8. An injection molding method for injection molding a PBT raw material into a valve according to any one of claims 1 to 7, characterized in that: The injection molding method includes raw material drying, screw pre-molding and injection molding; during the raw material drying process, the raw material needs to be dried at a temperature of 60-80 degrees for 4-5 hours; during the screw pre-molding process, the ratio of the feeding section, the compression section and the metering section is 1:1:1, the material temperature range is 240-270 degrees, and the material stays in the screw for no more than 15 minutes; during the injection molding process, the mold temperature range is 50-80 degrees, the material stays in the hot runner for no more than 3 minutes, the hot runner temperature is 240-270 degrees, the injection pressure range is 1000-1400bar, the holding pressure is set at 50%-70% of the injection pressure, the back pressure is 5-100bar, and the cooling time is 5-8 seconds.

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