WO2004070261A1

WO2004070261A1 - Overpressure safety apparatus of aerosol container

Info

Publication number: WO2004070261A1
Application number: PCT/KR2004/000165
Authority: WO
Inventors: Young-Seok Lee; Joon-Hyeok Chang
Original assignee: Kim Hyeon Suk; Young-Seok Lee
Priority date: 2003-02-06
Filing date: 2004-01-30
Publication date: 2004-08-19
Also published as: KR20040071484A

Abstract

The present invention relates to an overpressure safety apparatus of an aerosol container, wherein the safety apparatus prevents the aerosol container from exploding by exhausting overpressure gas out of the aerosol container using a safety valve, in case an internal pressure of the aerosol container is higher than predetermined level. The overpressure safety apparatus of an aerosol container having a container body and a mounting cap mounted on a top of the container, the safety apparatus having a housing coupled on the mounting cap, the housing having a main receiving cavity to receive valve stem and a first spring, and a liquid introducing passage connected to the main receiving cavity, a valve stem disposed in the housing and elastically supported by the first spring disposed in the housing, an opening/closing seal inserted between a top of the housing and the mounting cap to selectively open/close the orifice of the valve stem, a sub-housing formed on a side of the housing in one-piece, the sub-housing having a relief hole and a sub-receiving cavity with a bottom communicating with the relief hole and a top communicating with an exhaust hole formed on the mounting cap, and a safety valve disposed in the sub-receiving cavity to selectively open the relief hole in response to variation of internal pressure of the container.

Description

OVERPRESSURE SAFETY APPARATUS OF AEROSOL CONTAINER

TECHNICAL FIELD

The present invention relates to an overpressure safety apparatus of an aerosol container, and more particularly, to an overpressure safety apparatus of an aerosol container, which can prevent the aerosol container from exploding by exhausting overpressure gas out of the aerosol container using a safety valve in response to internal overpressure of the container due to external high temperature.

BACKGROUND ART

Generally, aerosol containers used for a hair spray, a spray type insecticide or the like are filled with aerosol. The aerosol is sprayed out of the aerosol container by internal pressure regularly maintained in the aerosol container. The aerosol filled in the container includes a functional liquid and a liquefied gas for injection of pressurizing the functional liquid. The liquefied gas includes a gas collected at an upper portion of the container and a gas dissolved in the functional liquid. Hereinafter, for the convenience of description, the functional liquid and the liquefied gas dissolved in the function liquid are referred to as 'liquid' and the gas not dissolved in the functional liquid and the liquefied gas being filled into the aerosol container are referred to as 'gas'.

The internal gas pressure may be increased at a high temperature, causing an inadvertent accident such as the deformation and explosion of the aerosol container.

For example, when the aerosol container is exposed to, for example, the heat of summer, since the internal pressure of the aerosol container is excessively increased, an inadvertent accident such as the explosion of the container may be incurred. Figs, la to lc show a conventional aerosol container. As shown in the drawings, a conventional aerosol container 100 includes a main body 99 and a mounting cap 101 mounted on a top of the main body 99. The mounting cap 101 is provided at a central portion with a projected coupling portion 102 in which a valve stem 103 and a housing 104 are coupled. A spring 105 being disposed in the housing 104 elastically supports the valve stem 103 upward. An opening/closing seal 106 is disposed between a top of the housing 104 and the coupling portion 102 of the mounting cap 101. A liquid-spraying hole 107 is defined by an upper-inner cavity of the valve stem

103. A concave portion 108 is formed on an outer circumference of the valve stem 103. An orifice 109 is formed through the concave portion 108 of the valve stem 103. The inner circumference of the opening/closing seal 106 is tightly fitted around the concave portion 108 so that the orifice 109 can be selectively opened and closed in response to external force to exhaust the internal liquid.

A predetermined level of internal pressure regularly acts in the aerosol container to spray the liquid to an external side. However, when the internal pressure is increased due to the external heat, an inadvertent accident may be incurred due to a risk such as the deformation and explosion of the container. Therefore, to prevent such an accident, there is provided a conventional safety apparatus against excessive internal pressure as shown in Fig. 2a.

As shown in the drawing, a housing 202 is coupled to a center of a mounting cap 201 and a valve stem 203 is installed in the housing 202. An over pressure safety spring 204 and a supporting spring 205 are disposed in the housing 202 to elastically support the valve stem 203. Disposed on a hook step 202a of the housing 202 is an opening/closing seal 202a on which a spring seat 207 is disposed.

The opening/closing seal 206 is tightly fitted around a concave portion 203a of the valve stem 203 to selectively open an orifice 208 formed through the valve stem 203. The spring seat 207 is fitted around the valve stem 203 and is biased by the over pressure safety spring 204 to allow the opening/closing seal 206 to tightly contact the hook step 202a.

In the above-described safety apparatus, in order to exhaust or fill a liquid out of or in the container 200, when external force is applied to push down the valve stem 203 as shown in Fig. 2b, the supporting spring 205 is compressed and the orifice 208 blocked by the opening/closing seal 206 is opened, thereby allowing the liquid to be exhausted out of or filled in the container 200.

Meanwhile, when the internal pressure of the container 200 is increased to be higher than the elastic force of the over pressure safety spring 204, as shown in Fig. 2c, the over pressure safety spring 204 is compressed and the valve stem 203 is moved upward. As a result, the opening/closing seal 206 is separated from the hook step 202a to define a liquid exhaust path. The liquid forming the excessive internal pressure is exhausted through the liquid exhaust path and an inner cavity of the housing 202, thereby lowering the internal pressure to prevent the explosion of the container 200. However, since the above-described safety apparatus is designed such that the liquid is introduced into the container only through the orifice 208 in the course of filling the liquid into the container (an opposite direction of the arrow in Fig. 2b), the filling efficiency is deteriorated as compared with a filling structure of a conventional aerosol container without the safety apparatus shown in Fig. lc. Also, since a submerged tube 211 connected to a lower end of the housing 202, for exhausting liquid is always submerged in the liquid, an overpressure in a state of Fig. 2a that the container is not used may cause the liquid to be leaked to an outside, thereby contaminating the container 200 and its surrounding.

Meanwhile, the safety apparatus is designed such that the internal over pressure liquid is exhausted by moving the valve stem 203 installed in the housing 202, an overall length of the valve stem 203 and the housing 202 is increased by the moving distance, thereby increasing the costs of the assembling parts.

DISCLOSURE OF INVENTION Accordingly, the present invention is directed to a safety apparatus of an aerosol container that substantially obviates one or more problems due to limitations and disadvantages of the related art.

An object of the present invention is to provide a safety apparatus of an aerosol container that can prevent explosion of the container by operating a safety valve installed in a sub-housing when internal pressure is excessively increased and exhausting a gas located at an upper portion of the container, the sub-housing having an exhaust passage formed at a portion of a housing, while maintaining cleanness of the container or its surroundings.

Another object of the present invention is to provide a safety apparatus that can prevent gas from being needlessly exhausted by blocking a relief hole by returning the safety valve to an initial location when internal gas pressure is reduced to a predetermined level.

A further object of the present invention is to provide a safety apparatus that can reduce manufacturing costs and can be employed to an existing assembling line for assembling an aerosol container not having a safety apparatus not by changing a design of a conventional filling structure but by simply installing a safety valve in a sub- housing integrally formed with a housing.

Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objectives and other advantages of the invention may be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

To achieve these objects and other advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, there is provided an overpressure safety apparatus of an aerosol container having a container body and a mounting cap mounted on a top of the container, the safety apparatus comprising a housing coupled on the mounting cap, the housing having a main receiving cavity to receive a valve stem and a first spring, and a liquid introducing passage communicating with the main receiving cavity; a valve stem disposed in the housing and elastically supported by the first spring disposed in the housing; an opening/closing seal inserted between a top of the housing and the mounting cap to selectively open close the orifice of the valve stem; a sub-housing formed on a side of the housing in one-piece, the sub- housing having a relief hole and a sub-receiving cavity with a bottom communicating with the relief hole and a top communicating with an exhaust hole formed on the mounting cap; and a safety valve disposed in the sub-receiving cavity to selectively open the relief hole in response to variation of internal pressure of the container.

According to an embodiment of the present invention, the safety valve comprises an opening/closing member installed on the bottom of the sub-receiving cavity to selectively open the relief hole, a second elastic member installed in the sub- receiving cavity and seated on the opening/closing member, and a seal ring disposed on the top of the sub-receiving cavity and inserted between a top of the elastic member and the mounting cap.

Preferably, the opening/closing member is provided at a top with a supporting boss for supporting a lower end of the elastic member to prevent the elastic member from deforming in a lateral direction.

Preferably, the housing is provided with at least one balance weight integrally formed on a side of the housing, the balance weight having the same shape as and symmetric with the sub-housing. It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. la is a section view of a conventional aerosol container;

Fig. lb is a sectional view illustrating a liquid spraying state of a conventional aerosol container depicted in Fig. la;

Fig. lc is a sectional view illustrating a gas filling state into a conventional aerosol container depicted in Fig. la; Fig. 2a is a sectional view of a safety apparatus of a conventional aerosol container;

Fig. 2b is a sectional view illustrating a liquid spraying state of a safety apparatus depicted in Fig. 2a;

Fig. 2c is a sectional view illustrating an operation state of a safety apparatus depicted in Fig. 2a when internal pressure is increased above a predetermined level; Fig. 3a is a sectional view illustrating a safety apparatus of an aerosol container according to a preferred embodiment of the present invention;

Fig. 3b is a sectional view illustrating an operation state under a regulated pressure of a safety apparatus depicted in Fig. 3 a; Fig. 3c is a sectional view of a gas filling state into an aerosol container depicted in Fig. 3 a;

Fig. 3d is a sectional view illustrating an operation state of a safety apparatus depicted in Fig. 2a when internal pressure is increased above a predetermined level;

Fig. 4 is a partial exploded perspective view of a safety apparatus of an aerosol container according to a preferred embodiment of the present invention;

Fig. 5a is a sectional view illustrating a safety apparatus of an aerosol container according to another preferred embodiment of the present invention; and

Fig. 5b is a partial exploded perspective view of a safety apparatus of an aerosol container according to another preferred embodiment of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION

Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.

Fig. 3a is a sectional view illustrating a safety apparatus of an aerosol container according to a preferred embodiment of the present invention, Fig. 3b is a sectional view illustrating an operation state under a regulated pressure of the safety apparatus depicted in Fig. 3a, Fig. 3c is a sectional view of a liquid filling state into an aerosol container depicted in Fig. 3a, Fig. 3d is a sectional view illustrating an operation state of a safety apparatus depicted in Fig. 3a when internal pressure is increased above a predetermined level, and Fig. 4 is a partial exploded perspective view of a safety apparatus of a aerosol container according to a preferred embodiment of the present invention. As shown in the drawings, a mounting cap 10 is coupled on a top of a body 2 of an aerosol container 1 in which a functional liquid and a liquefied gas for injection are filled. The mounting cap 10 is provided at a center with a coupling portion 11 in which a valve stem 20 and a housing 30 are coupled. Coupled in the housing 30 is a spring 40 for biasing the valve stem 20 upward. An opening/closing seal 50 has an outer circumference, which is tightly fixed between a top of the housing 30 and the coupling portion 1 1 of the mounting cap 10.

The housing 30 includes a main receiving cavity 31 receiving the valve stem 20 and a spring 40 at a center portion thereof, , and a liquid introducing passage 32 communicating with the main receiving cavity 31. The liquid introducing passage 32 is detachably coupled with a front end of a liquid suction conduit 33.

Since a level of liquid filled in the container 1 is lowered as used, the other end of the liquid suction conduit 33 extends close to a bottom of the container 1 such that a remnant liquid is effectively inhaled. A sub-housing 60 is formed integrally with the housing 30, and has a relief hole

61 and a sub-receiving cavity 62 with a bottom communicating with the relief hole 61 and a top communicating with an exhaust hole 12 formed on the mounting cap 10. A safety valve 70 is disposed in the sub-receiving cavity 62 to selectively open the relief hole 61 in response to variation of internal pressure of the container 1. The exhaust hole 12 formed in the mounting cap 10 is to exhaust an overpressure gas. The exhaust hole 12 is conventionally formed using a progressive dieset by which processes of drawing, cutting and so on are done just one time, but can be formed using the existing progressive dieset without changing design of the dieset by installing a punch. The valve stem 20 has an upper portion, which is inserted into the coupling portion 1 1 by penetrating the mounting cap 10, a lower portion, which is disposed in the housing 30 to be biased upward by the spring 40, and a liquid-spraying hole 21, which is formed in an upper-inner portion of the valve stem 20.

Further, a ring-shaped concave portion 22 is formed on an outer circumference of the valve stem 20, and an orifice 22 is formed on the concave portion 22 in a horizontal direction. The opening/closing seal 50 has an inner circumferential portion, which is tightly fitted around the concave portion 22, thereby blocking liquid from being exhausted to the orifice 23.

Meanwhile, the sub-housing 60 is provided at an inner lower portion with the relief hole 61 and is also provided at an inner upper portion with a sub-receiving cavity 62 having a lower portion communicating with the relief hole 61 and an upper portion communicating with the exhaust hole 12 formed on the mounting cap 10.

A safety valve 70 is installed in the sub-receiving cavity 62 of the sub-housing 60, and is opened when the internal pressure of the container 1 is higher than a predetermined pressure and is closed when the internal pressure of the container 1 is lower than the predetermined pressure.

The safety valve 70 includes an opening/closing member 71 installed on a bottom of the sub-receiving cavity 62 to selectively open the relief hole 61, an elastic member 72 installed in the sub-receiving cavity 62 and seated on the opening/closing member 71, and a seal ring 73 disposed on a top of the sub-receiving cavity 62 and inserted between a top of the elastic member 72 and the mounting cap 10.

The elastic member 72 is preferably a spring capable of extendable in a lengthwise direction, more preferably, is a cylindrical coil spring having advantages of easy design and manufacturing, such as selection of elastic coefficient. The opening/closing member 71 is designed having a flat bottom, and is provided at an upper portion with a supporting boss 71a. A lower end of the elastic member 72 is inserted onto the supporting boss 71a of the opening/closing member 71. Therefore, it can be avoided that the elastic member 72 is deformed in a lateral direction against compression force applied in a longitudinal direction. The seal ring 73 disposed between the top of the elastic member 72 and the mounting cap 10 is formed of a deformable rubber material to provide sealing between a top of the sub-housing 60 and the mounting cap 10, thereby preventing the internal gas from leaking out of the container 1.

A lower end of the seal ring 73 is biased by the elastic member 72 to tightly contact with a bottom of the mounding cap 10 around the exhaust hole 12. A circular projection 63a is formed on a bottom surface 63 of the sub-receiving cavity 62 defined in the sub-housing 60. The circular projection 63a has a diameter that is greater than an inner diameter of the relief hole 61. Therefore, when the relief hole 61 is closed by the opening/closing member 71, the opening/closing member 71 tightly contacts the circular projection 63a, enhancing the seal effect.

At least one balance weight 64 having the same shape as the sub-housing 60 is integrally formed on a side of the housing symmetric with the sub-housing 60 such that mass of the housing 30 and the sub-housing 60 may be balanced.

Herein, the housing 30, the sub-housing 60 and the balance weight 64 are integrally injection molded by synthetic resin.

The mounting cap 10 is provided with seating guide steps 13, which are formed outside the exhaust hole 12 to guide an assembly of the sub-housing 60 and the balance weight 64, and to prevent the sub-housing 60 and the balance weight from displacing.

An operation of the safety apparatus of the present invention will now be described.

In normal use, when the valve stem 20 is pushed downward by an external force to spray liquid out of the aerosol container 1 , the spring 40 is compressed as shown in Fig. 3b and the orifice 23 is opened by the opening/sealing seal 50.

Accordingly, the liquid filled in the container 1 is sprayed out of the container 1 along a direction indicated by an arrow, that is, via the liquid suction conduit 33, the liquid introducing passage 32, the main receiving cavity of the housing 30, the orifice 23 of the valve stem 20, and the liquid-spraying hole 21.

When a user intends to fill the container 1 with a gas, the filling of the gas is performed in an opposite direction to the spraying process. That is, as shown in Fig. 3c, about 20% of the gas is filled in the container 1 through the above mentioned liquid exhaust path and remaining 80% is introduced into a space between the coupling portion 11 of the mounting cap 10 and the housing 30, and filled via the main receiving cavity 31. Therefore, the filling efficiency is not deteriorated, and is not affected by the safety apparatus of the present invention. When the external force applied to the valve stem 20 is removed, the valve stem 20 returns to its initial position by the biasing force of the spring 40, whereby the opening/closing seal 50 also returns to its initial position to close the orifice 23 of the valve stem 20, interrupting the exhaust of the liquid. Meanwhile, when internal pressure of the container 1 becomes higher than the predetermined level, i.e., elastic force of the elastic member 72 as shown in Fig. 3d, the gas pressure acting on the bottom of the opening/closing member 71 through the relief hole 61 compresses the elastic member 72 so that the opening/closing member 71 can be spaced away from the bottom surface 63. As a result, the excessive internal pressure in the aerosol container 1 is exhausted to an external side through the relief hole 61, a gap defined between the opening/closing member 71 and the bottom surface 63, the sub-receiving cavity 60 and the exhaust hole 12, thereby reducing the internal pressure to prevent the explosion of the aerosol container 1 that may be caused by the overpressure. After the above, when the internal pressure is reduced to the standard value, the opening/closing member 71 is restored to its initial position by biasing force of the elastic member 72 to tightly contact the bottom surface 63 of the sub-housing 60. As a result, the relief hole 61 is blocked by the opening/closing member 71 to prevent the gas in the container 1 from needlessly exhausting as shown Fig. 3 a. It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention. Thus, it is intended that the present invention covers the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.

For example, Figs. 5a and 5b show another embodiment of the present invention, wherein the sub-housing 60 is provided at a lateral portion with a circular rim 65 formed integrally, and the circular rim 65 is concentric with the main receiving cavity 31 and connected to the housing 30 via a plurality of arms 66 reinforcing the circular rim 65 and the housing 30. Herein, thickness and number of the circular rim 65 and the arms 66 are properly selected for mass balancing with the sub-housing 60. INDUSTRIAL APPLICABILITY

As described above, in the safety apparatus of the present invention, when internal pressure of the aerosol container is increased above a predetermined level, the overpressure can be released by exhausting a gas floating above a liquid out of the container with the safety valve, preventing the deformation or explosion of the aerosol container.

A drop off in filling efficiency due to a conventional safety valve provided in an aerosol container is also prevented.

Further, a gas, not a liquid, is exhausted via a safety valve and spread away, so it doesn't contaminate the aerosol container or its surroundings and good sanitary condition is maintained.

In addition, when the internal pressure is reduced to a standard value, the safety valve is restored to its initial position to prevent the gas in the container from needlessly exhausting, thereby enabling reuse of the container. Furthermore, a valve stem is not changed in its design and an additional sub- housing for installing a safety valve is simply added, thereby, avoiding the troublesome of design change and reducing the manufacturing costs, compared with a conventional safety apparatus which change the housing design and dispose a safety valve therein.

Furthermore, the aerosol container with the inventive safety apparatus is designed to use an existing assembly line for the aerosol container not having the safety apparatus with a trivial line change. Thereby adopted easily in the existing manufacturing line for the aerosol container products.

Claims

WHAT IS CLAIMED:

1. An overpressure safety apparatus of an aerosol container having a container body 2 and a mounting cap 10 mounted on a top of the container, the safety apparatus comprising: a housing 30 coupled on the mounting cap 10, the housing having a main receiving cavity 31 to receive a valve stem 20 and a first spring 40, and a liquid introducing passage 32 communicating with the main receiving cavity 31; a valve stem 20 disposed in the housing 30 and elastically supported by the first spring 40 disposed in the housing 30; an opening/closing seal 50 inserted between a top of the housing 30 and the mounting cap 10 to selectively open/close the orifice of the valve stem 20; a sub-housing 60 integrally formed on a side of the housing 30, the sub-housing 60 having a relief hole 61 and a sub-receiving cavity 62 with a bottom communicating with the relief hole and a top communicating with an exhaust hole 12 formed in the mounting cap; and a safety valve 70 disposed in the sub-receiving cavity 62 to selectively open the relief hole 61 in response to variation of internal pressure of the container.

2. The safety apparatus of claim 1, wherein the safety valve 70 comprises an opening/closing member 71 installed on the bottom of the sub-receiving cavity 62 to selectively open the relief hole 61, a second elastic member 72 installed in the sub- receiving cavity 62 and seated on the opening/closing member 71, and a seal ring 73 disposed on the top of the sub-receiving cavity 62 and inserted between a top of the second elastic member 72 and the mounting cap 10.

3. The safety apparatus of claim 2, wherein the second elastic member 72 is a cylindrical coil spring.

4. The safety apparatus of claim 2 or 3, wherein the opening/closing member 71 is provided at a top with a supporting boss 71a for supporting a lower end of the second elastic member 72 to prevent the second elastic member 72 from deforming in a lateral direction.

5. The safety apparatus of claim 1, wherein the sub housing 60 is provided at an inner bottom surface 63 thereof with a circular projection 63a having a diameter larger than an inner diameter of the relief hole 61.

6. The safety apparatus of claim 2, wherein the seal ring 73 is formed of a rubber material.

7. The safety apparatus of any one of claim 1 and 2, wherein the housing 30 is provided with at least one balance weight 64 formed on a side of the housing 30, the balance weight 64 having the same shape as and symmetric with the sub-housing 60.

8. The safety apparatus of claim 7, wherein the mounting cap 10 is provided with a seating guide step 13 for guiding a fitment of an upper portion of the sub-housing 60 to the mounting cap 10.

9. The safety apparatus of claim 1 or 2, wherein the sub-housing 60 is provided at a lateral portion with a circular rim 65 formed integrally, the circular rim 65 being connected with the housing 30 by a plurality of arms 66.