US 3519172 A
Description (OCR text may contain errors)
July 7, 1970 J, BRUCE 3,519,172
FLUID DISPENSER Filed March 1, 1968 /i /7fl I INVENTOR. Lfd/m/ KEP/Mf United States Patent 3,519,172 FLUID DISPENSER John K. Bruce, Burbank, Calif., assignor to Sterigard Company, Burbank, Calif., a California limited partnership Filed Mar. 1, 1968, Ser. No. 709,563 Int. Cl. 365d 83/14 U.S. Cl. 222396 15 Claims ABSTRACT OF THE DISCLOSURE The dispensing valve of this fluid dispenser has a stem with a pressure vent port and a stemport. These ports are separated by a partition and communicate respective passages with the outside of the stem. The stem is springbiased to maintain the pressure vent port normally within the dispenser and out of communication with the dispensers exterior. Upon reaching a predetermined excessive pressure, the stem moves against the spring bias to position the pressure vent port outside the dispenser and, through its passage, relieve the excessive pressure buildup within the container.
BACKGROUND OF THE INVENTION This invention relates in general to the art of fluid dispensers and, more in particular, to a safety device toprevent excessive pressure buildups in fluid dispensers.
Pressurized fluid dispensers are extremely popular. These dispensers maintain a product to be dispensed under pressure and sealed within them. A dispensing valve is employed to selectively discharge the product.
When heated, the pressure within these dispensers increases. The pressure often increases to such an extent that the container will eatastrophically explode. This explosion hazard is present whether the dispenser contains product or whether it is empty. In the latter instance, there is still gas in the container of suflicient quantity to expand under heat and cause an explosion. Accidents are common, for example, where the user of the dispenser inadvertently places it close to a source of heat between usages. In this instance, the consumer is always exposed to the possibility of serious injury. Even when the dispenser is thrown away, it is not uncommon that it finds itself in an open fire or a furnace with the inevitable result of an explosion and possible injury to people close by.
To avoid explosion hazards, several concepts have been proposed. One of these concepts is to have a weakened section in the wall of the dispenser. The weakened section is designed to relieve the pressure within the dispenser, when it becomes sufl'iciently high, by opening its interior to atmosphere. This concept generally takes two forms. One form is purely pressure sensitive. This dispenser wall is weakened to either allow a plug section to blow out or the dispenser to separate in half. The other form employs a low melting point plug which, upon reaching a sufficiently high temperature, melts to communicate the interior of the dispenser with atmosphere. Both devices operate to vent the interior of the dispenser very rapidly because the pressure at which venting occurs is high. Rapid product venting often leads to disaster. For example, if the contents of the dispenser are flammable their escape in a fire creates a flamethrower effect. In addition, if the plugs or weakened section are not formed correctly the contents of the dispenser may escape prematurely.
Another concept is to break the dispensing valve after the dispenser is emplty in such a manner as to vent the dispensers interior. This concept does not guard against the explosion hazard while the dispenser still contains ice product. In addition, inadvertent destruction of the dispensing valve, while product remains, is itself a hazard because the product will escape very rapidly. Moreover, such inadvertent destruction is wasteful of the product.
Still another concept envisions the freezing of an empty pressurized dispenser and then puncturing the dispenser. To avoid an explosion hazard by having each and every dispenser frozen and punctured by its user is an extremely unreliable and arduous way to safety. Moreover, the concept does not avoid the hazard of explosion while product yet remains in the dispenser.
Therefore, there is an urgent need for pressurized dispensers which vent their interior gradually and reliably without user attention when the dispensers are subjected to heat or other agents of accidental pressure buildup.
SUMMARY OF THE INVENTION The present invention provides an improvement in pressurized dispensers which avoids the problem of explosion by venting a containers interior when it reaches a predetermined pressure without the attention of the consumer.
The invention employs a dispensing value having a stem with a pressure vent port communicating a passage in the stem with the stems interior. The stem is biased inwardly of the dispenser to maintain the pressure vent port out of communication with atmosphere. The bias is such, however, that upon reaching a predetermined excessive pressure, the pressure vent port moves in response to such pressure outside the dispenser. Product is then discharged through the relieving pressure vent port because the port is in product communication with the interior of the dispenser through the passage. Means are also provided for selectively dispensing product through the dispensing valve.
In one form, the invention contemplates a fluid dispenser of the type wherein the dispenser is sealed and the fluid to be dispensed is dispensed by a dispensing valve. The dispensing valve has a stem which is spring-biased in the direction of the dispensers interior. The stem has a dispensing and a venting passage separated by a partition. The dispensing passage is normally disposed out of communication with the dispensers interior while the venting passage is normally disposed within the dispenser. The pressure vent port passes through the wall of the stem into the venting passage. The venting passage is also open to the interior of the dispenser. Means are provided to communicate the interior of the dispenser and discharge product through the dispensing passage at the behest of the user. This may be done by a product port through port through the wall of the stem into the dispensing passage. Upon depression of the stem by the user, the product port communicates the dispensing passage with the interior of the dispenser.
In preferred form, the improved dispensing valve is carried by a valve cup. A housing having an axial bore is mounted interiorly of the dispenser and held by the cup. The stem is spring-biased inwardly of the container by a first spring acting on a flange at the lower end of the stem. A return spring in the bore urges against the bottom of the flange and the housing to effect return of the stem to its unactuated position. A seal is provided about the stem to prevent product leakage where the stem leaves the cup. Product within the dispenser is in communication with the venting passage of the stem through the housing which is open for this purpose.
In use, an excessive pressure buildup within the dispenser forces the stern upward against the action of the biasing spring until the pressure vent port is exposed to atmosphere. At this time, the contents of the dispenser will be vented through the venting passage and out the pressure vent port to atmosphere.
The present invention marks a material advance in the safety of pressurized dispensers. The pressure vent port in the stem will rise in response to pressure buildup within the dispenser. This port will vent the dispensers interior and relieve the pressure, when suflicient pressure exists to overcome the inward bias. The stem in which the port is disposed is spring-biased inwardly. The spring bias insures against rapid and often catastrophical venting of the dispensers interior. Moreover, inasmuch as the pressure vent port is carried by the dispensing valves stem, venting may be against the interior side wall of the valve cup. This effectively distributes the vented product into a small area and dissipates its force. This is an important feature when, for example, the contents of the dispenser are flammable. In addition, the contents are discharged gradually and not catastrophically because as pressure is relieved the biasing spring will return the pressure vent port into the inside of the container to prevent further escape. When pressure again increases, the stem will translate to communicate the pressure vent port with atmosphere.
Thus, the pressure dispensing valve of the present invention avoids all the problems attendant. with the concepts previously proposed. The valve is pressure sensitive and therefore consumer attendance to safety is not required. It is not necessary to freeze the dispenser and puncture it after its contents have been emptied or to fracture the dispensing valve to communicate the interior of the dispenser with atmosphere. Relative to these latter concepts, the dispensing valve of the present invention is safe not only when product is within the dispenser but when the dispenser is empty, a feature absent in the prior art. In addition, expensive and unreliable weakened sections are avoided and therefore the problem of catastrophic discharge of the dispensers contents is also avoided.
These and other features, aspects and advantages of the present invention will become more apparent from the following description, appended claims and drawings.
BRIEF DESCRIPTION OF THE FIGURES FIG. 1 is a view of the improved dispensing valve in its associated pressurized dispenser;
FIG. 2 is a partial view, in half. section, of the preferred form of the dispensing valve of the present invention;
FIG. 3 is a fragmentary view showing the path of product prior to its discharge;
FIG. 4 shows how the product is discharged through a a product port; and
FIG. 5 shows how product is vented when an excessive pressure is reached within the dispenser.
DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 depicts the general combination. A dispenser or container has a dispensing valve 12 mounted in its cover or cap 14. Except for the dispensing valve, the dispenser may be of standard construction. A closed body portion 16 is connected to cover 14. The product to be dispensed is contained in dispenser 10 under pressure. The product is dispensed through. actuation of dispensing valve 12. Because the product is maintained at a pressure, it is necessary that dispenser 10 be sealed.
FIG. 2 depicts in detail the improved dispensing valve 12 of the present invention. This assembly includes a valve cup 18, a valve stem 20 and an actuator 22.
Stem 20 includes an upper portion 24 and a lower portion 26. Upper portion 24 has a product dispensing passage 28 in communication with a dispensing orifice 30 of actuator 22. A product port 32 extends through the wall of upper portion 24 to communicate passage 28 with atmosphere. The position of the product port illustrated is typical, but it may be normally out of communication with atmosphere. It is only necessary that product port 32 be out of communication with the dispensers interior when valve 12 is in its unactuated position.
Lower portion 26 includes a venting passage 34 which extends downward into the interior of dispenser 10. A pressure vent port 36 is at the upper end of venting passage 34 and extends through. the wall of lower portion 26 to communicate passage 34 with the exterior of stem 20. The lower end of passage 34 is open. A partition 38 separates dispensing passage 28 from venting passage 34. An external annular flange 40 forms the base of stem 20.
A housing 42 couples stem 29 and its carried actuator 22 to the balance of dispenser 10. The housing includes a generally cylindrical upper portion 44 and a generally cylindrical lower portion 46 of smaller diameter. An interior cylindrical bore 48 extends through upper portion 44 and terminates at the base of lower portion 46.
Valve cup 18 is formed with a generally toroidal channel 50 which is bounded by exterior vertical wall 52 and interior vertical wall 54. An annular, outwardly extending, radial crimp 55 is formed in wall 52 and bears on the interior surface of cover 14 to firmly secure valve cup 18 in place. The base of the channel is defined by a generally annular horizontal portion 56 which connects vertical walls 52 and 54. The space inwardly of vertical wall 54 is bridged by horizontal portion 58. Valve stem 20 extends through a hole in this horizontal portion.
Vertical wall 54 has an inwardly extending flange 60 which may be formed by crimping. Cylindrical portion 44 of housing 42 is secured in position by this annular flange. A seal 62 is disposed between top portion 58 and the top of cylindrical portion 44. Stem 20 extends through this seal. The seal prevents product from leaving the interior of the dispenser through the opening in horizontal portion 58 through which stem 20 passes. An annular, upwardly extending flange 64 on the upper surface of cylindrical portion 44 bears against the lower surface of seal 62. This flange creates a seal between top portion 58 and the upper surface of seal 62 immediately above the flange.
Valve cup 18 has an annular lip 66 which is crimped over a mating lip 68 of cover 14 to secure the cup to the balance of the dispenser.
A pressure or biasing spring 70 is disposed within bore 48 of housing 42 and bears against the upper surface of external flange 40 of stem 20 and the lower surface of seal 62. A return spring 72 is also disposed in bore 48 but on the other side of external flange 40. This spring bears against the lower surface of flange 40 and the base of housing 42. Pressure spring 70 biases stem 20 to normally maintain pressure vent port 36 interiorly of the dispenser and product port 32 outside the dispenser. Spring 72 returns stem 20 to the position shown in FIG. 2 after each use of the dispenser. Spring 70 exerts a downward force on stem 20 through flange 40 even while the pressure in the container is urging stem 20 upward.
Bore 48 of housing 42 is in product communication with the interior of container 10 through a passage 74. The product exerts pressure on stem 20 and tends to drive the stem upward. The effective area of stem 20 which feels this upward pressure is equal to the sum of the area of partition 38 and the cross sectional area of the walls of lower portion 26 of stem 20. In normal usage, spring 7 0 will exert a force on stem 20 which is balanced by the pressure within the dispenser felt by this effective area and spring 72.
FIGS. 3 through 5 depict the operation of the improved dispensing device of the present invention.
In FIG. 3, stem 20 is in its unactuated position. In this position, dispensing passage 28 is open to atmosphere through product port 32 and dispensing orifice 30. Within the dispenser, product occupies the interior of housing 42 both above and below flange 40. Product is also in venting passage 34 of stem 20. Product will flow through pressure vent port 36 into the space above flange 40. This is shown by the arrows in FIG. 3.
As is seen in FIG. 4, when valve 12 is actuated, stem 20 is depressed inwardly against the force of spring 72. to lower product port 32 inside the dispenser. When port 32 is within the dispenser, product communication into dispensing passage 28 is effected by product flow through this port from that portion of bore 48 above flange 40. Product flows into this space through pressure vent port 36. Product then flows through port 32, into passage 28 and out through dispensing orifice 30.
When the pressure within dispenser builds up gradually, it will act against stem and against the restoring force of spring 70 to raise the stem upward to a point where pressure vent port 36 is in communication with atmosphere. Venting will be gradual because port 36 will not be completely open to atmosphere. Product will then flow through venting passage 34 until the pressure within the dispenser is reduced sufliciently for spring 70 to lower stem 20 and its pressure vent port 36 into the dispenser. In an aggravated case, when the pressure buildup is rapid and great, port 36 will be forced completely outside the dispensers interior and remain there until almost all the gaseous contents of the dispenser are discharged through it. In this aggravated case, as seen in FIG. 2, product discharge through pressure vent port 36 will be against vertical wall 52 of valve cup 18. This tends to isolate the discharge into a very limited area and reduce its force. This feature is particularly valuable with inflammables. The restoring force presented by spring 70 on stem 20 insures that product discharge through port 36 is gradual because the port will always tend, except wh n there is excessive pressure, to return to within the dispenser.
What is claimed is:
1. In combination with a fluid dispenser having a dispensing valve of the type adapted to contain a fluid product under pressure, an improvement in the dispensing valve comprising:
(a) a movable valve stem having a venting passage open to the interior of the dispenser and a pressure vent port through the wall of the stem in communication with the passage;
(b) biasing means to urge the stem inwardly of the dispenser to maintain the pressure vent port normally out of communication with atmosphere, the biasing means and valve stem being operable in response to a predetermined, excessive pressure to allow the valve stem to move to a position where the pressure vent port is exposed to atmosphere and relieve the dispenser by venting the dispensers interior; and
(c) means for selectively dispensing fluid from the dispenser, the selective dispensing means including a dispensing passage in the stern which is normally out of communication with the dispensers interior and a product port opening into the dispensing passage through the wall of the stem, the product port communicating the dispensers interior with the dispensing passage when the selective dispensing means is actuated.
2. The improvement claimed in claim 1 including return biasing means for returning the stem to an unactuated position after actuation of the selective dispensing means.
3. The improvement claimed in claim 2 including a housing mounted in the dispenser having a central bore, the stem being slidably disposed in the central bore.
4. The improvement claimed in claim 3 wherein the stem biasing means includes a spring disposed within the bore of the housing and coupled to the stem to urge it inwardly of the dispenser, and the return biasing means includes a spring disposed within the bore of the housing below the stem and coupled to the stem to urge it up- Wardly.
5. The improvement claimed in claim 4 including an external flange at the lower end of the stem, the stem biasing and return springs urging against opposite surfaces of the flange.
6. The improvement claimed in claim 5 wherein the housing is carried by a valve cup such that the pressure vent port, when exposed to atmosphere in response to a predetermined excessive pressure within the dispenser, is capable of discharging fluid product against a wall of the valve cup.
7. An improved fluid dispenser comprising:
(a) a closed container having an interior for storing a fluid product under pressure; and
(b) a dispensing valve mounted in the container -for selectively discharging the fluid product including:
(i) a movable valve stem having:
a venting passage in communication with the hollow interior; a pressure vent port through the wall of the stem into the venting passage; and means for selectively dispensing fluid from the container, the selective dispensing means including: and
a dispensing passage in the stem axially aligned with the venting passage and separated therefrom by a partition; and a product port through the wall of the stem into the dispensing passage, the product port being normally out of communication with the containers interior and positioned such that upon depression of the stem inwardly of the container the product port communicates the dispensing passage with the containers interior; and (ii) biasing means for maintaining the pressure vent port within the container when the pressure within the container is below a predetermined excessive pressure, the biasing means and valve stem being operable when such predetermined excessive pressure is reached to allow the valve stem to move outwardly of the container to expose the pressure vent port to atmosphere and relieve the excessive pressure.
8. The improved fluid dispenser claimed in claim 7 wherein:
(a) the biasing means includes a biasing spring operatively engaged to the valve stem to urge the valve stem inwardly of the container; and
(b) the selective dispensing means includes a return spring operatively engaged to the valve stem to urge the valve stem upwardly of the container, the valve stem being carried by the biasing spring and return spring.
9. The improved fluid dispenser claimed in claim 8 wherein:
the dispensing valve is carried by a valve cup such that the pressure vent port, upon exposure to atmosphere, is capable of discharging fluid product against a wall of the valve cup.
10. The improvement claimed in claim 3 wherein:
the stem biasing means and stem are operable to main tain the pressure vent port in communication with the central bore to provide fluid product thereto through the venting passage at pressures within the dispenser "below the predetermined excessive pressure, the product port communicating with the dispensers interior through the central bore when the selective dispensing means is actuated.
11. The improved fluid dispenser claimed in claim 7 wherein:
(a) the dispensing valve has an axial bore in communication with the hollow interior, the stern being received in the axial bore;
(b) the stem biasing means and stem are operable to maintain the pressure vent port in communication with the central bore to provide fluid product thereto through the venting passage at presssures within the container below the predetermined excessive pressure; and
(c) the product port communicates with the hollow interior through the axial bore when the selective dispensing means is actuated.
12. An improved dispensing valve for use with a pressurized fluid dispenser comprising:
(a) means for mounting the dispensing valve to the dispenser;
(b) a housing carried by the mounting means having an axial bore with an opening for fluid product communication with the interior of the dispenser;
(c) a stem received in the axial bore of the housing for axial movement therein between an unactuated position, an actuated position and a pressure relief position, the stem extending outwardly of the housing and having:
(i) a venting passage open to the axial bore of the housing,
(ii) a presssure vent port through the wall of the stem into the venting passage, the pressure vent port being within the housing in the unactuated and actuated positions and outside the housing in communication with atmosphere in the pres sure relief position,
(iii) a dispensing passage,
(iv) a product port through the wall of the stem into the dispensing passage, the product port being out of communication with the axial bore in the unactuated position and in communication with the axial bore in the actuated position, and
(v) a partition dividing the dispensing passage and the venting passage to prevent direct fluid communication between the two;
(d) means for biasing the stem against pressure within the dispenser such that the presssure vent port is within the housing at pressures within the dispenser below a predetermined excessive pressure, the biasing means and the stem being operable to allow the stem to move outwardly of the housing at pressures within the dispenser above the predetermined excessive pressure to the pressure relief position for communicating the pressure vent port with atmosphere; whereby when the dispensing valve is mounted on the dispenser and the predetermined excessive pressure is exceeded, the stem moves outwardly of the housing to the pressure relief position where the pressure vent port is in communication with atmosphere to relieve the excessive pressure by product discharge through the venting passage and pressure vent port to atmosphere, and at pressures below the predetermined excessive pressure, the displacement of the stem to the actuated position communicates the product port with the axial bore of the housing for the selective discharge of product.
13. The improved dispensing valve claimed in claim 12 wherein:
the pressure vent port is in communication with the axial bore of the housing at pressures below the predetermined excessive pressure to provide product communication between the axial bore and the interior of the dispenser through the venting passage.
14. The improved dispensing valve claimed in claim 13 including:
return biasing means for returning the stem to the unactuated position from the actuated position.
15. The improved dispensing valve claimed in claim 14 wherein:
(a) an external flange on the stem is provided;
(b) the stem biasing means includes a spring disposed within the axial bore of the housing and urging against the external flange to bias the stem toward the unactuated position and away from the pressure relief position; and
(o) the return biasing means includes a spring disposed within the axial bore of the housing and urging against the external flange to bias the stem toward the unactuated position and toward the pressure re-- lief position.
References Cited UNITED STATES PATENTS 1,913,509 6/1933 Rack 222-493 2,437,589 3/1948 Bink 222-493 3,005,577 10/1961 Webster 222-397 3,081,919 3/1963 Samuel 222-396 3,191,816 6/1965 Fead et a1. 1 222402.24 X 3,363,810 1/1968 Meshberg 222397 ROBERT B. REEVES, Primary Examiner F. R. HANDREN, Assistant Examiner US. Cl. X.R. 222402.24
$92 23 UNI'IEI) STA'IES IA'IIJNI OFFICE CERTlFICATE OF CORREC'IION Dated August ll, l970 Patent. No. 3 519 172 J K. Bruce ror appears in the above-identified patent reby corrected as shown below:
Inventor(s) It is certified that er and that said Letters Patent are he I- In the specification: Column 1, line 70 "emplty" Column 2 line 23, "value" should be should be --empty--. --valve--; line 51, delete "through port".
In the claims Claim 7 column 6, line 17 delete "and".
SIGNEUANU S EALEU OCTZOIQU Attest:
Edward Fletcher, Hi-11A! II- p m. M Gomissioner 0! pm Ancating Officer