Pressure-powered Aerosol Timer

Abstract

A pressure-powered variable timer for aerosol spray cans for automatically operating the can to periodically spray its contents at desired predetermined intervals, the pressure within the can being utilized to actuate the timer.

Description

BACKGROUND OF THE INVENTION

This invention pertains to automatic pressure-actuated timer devices, and is particularly directed to pressure-powered variable timer for actuating the spray mechanism of aerosol cans.

Heretofore, it has been difficult to provide any dependable device for periodically causing a spray to issue from an aerosol can and the like. Problems with long period actuation of the can spray mechanism have never proved reliable. Further, an all mechanical low-cost unit directly mounted on the can top and actuated from the pressure in the can has never been provided successfully because of mechanical defects and operation of these former devices.

SUMMARY OF THE INVENTION

One of the objects of this invention is to provide an aerosol can spray timer that is automatically actuated from the normal pressure within the can.

Another object is to provide an all mechanical timer of low cost which may be directly mounted on the spray can.

A further object is to provide a pressure-powered timer for an aerosol spray can which can be regulated for various and long time setting intervals of spraying.

It is also an object to utilize a sealed bellows circuit containing a high viscosity fluid for the precise and dependable operation of the timer device.

A final object is to provide a device as above with a dependable overcenter rotary valve for selectively controlling the application of operating pressure for the timer and the discharge of sprayed liquid.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a rear elevation of the exterior of the pressure-powered aerosol timer incorporating the features of this invention.

FIG. 2 is a top view of the apparatus shown in FIG. 1 with the cover removed, indicated by the line 2-2 in FIG. 3.

FIG. 3 is a sectional view on the line 3-3 of FIG. 2.

FIG. 4 is an enlarged fragmentary sectional view on the line 4-4 of FIG. 2.

FIG. 5 is an enlarged fragmentary sectional view on the line 5-5 of FIG. 3.

FIG. 6 is a sectional view similar to FIG. 5 but showing the control valve in a different position.

DESCRIPTION OF THE PREFERRED EMBODIMENT

As an example of one embodiment of this invention, there is shown an aerosol can 10 having the usual top 11 and actuable control valve 12 fixed in the cap 20 of the top 10 and having the discharge hose 13 connected to the intake tube 14 of valve 12 opening into the valve chamber 15 containing the shutoff valve disc 16. A compression spring 17 normally yieldingly holds the disc lip 18 in sealed contact with the rubber or plastic valve seat 19.

The pressure-powered timer comprises a main body 21 having a bell-shaped lower portion 22 which is adapted to snap into and secure the timer to the cap 20 as best shown in FIG. 3. A spout 23 is formed integral with the body 21 having a nozzle 24 on the outer end of the spout 23 which is in communication with a passageway 25 in the spout which opens into the valve bore 26 formed in the body 21.

A rotary valve plunger 27 revolves in the valve bore 26 and its upper end 28 engages in sealing relationship the turned over lip 29 formed in the upper end of the bore 26. The lower end of the plunger 27 has a counterbore 30 in which is provided a compression spring 31 which engages the top end of the spray can valve opening plug 32 in the main body 21 to hold the rotary valve plunger in proper sealing relationship with the lip 29. The lower end of the plug 32 engages the bottom of the counterbore 33 formed in the shutoff valve 16 so that when the bell-shaped lower portion 22 of the body 21 is pushed into securing position in the cap 20 as shown in FIG. 3, the valve 16 is pushed downward to release its lip 18 from the valve seat 19 so that fluid from the can 10 enters counterbore 33 and goes through the radially disposed notch 34 and up through the axial bore 35 in the plug 32 and then enters the counterbore 30 of the valve plunger 27.

Referring more particularly to FIGS. 5 and 6, the periphery of the rotary valve plunger 27 is provided with arcuate passageways 36 and 37, the longer of the two passageways 36 being in communication with the counterbore 30 through the radial passageway 38. The arcuate passageway 37 is always in communication with the nozzle passageway 25. Both passageways 37 and 38 are alternately connectable and disconnectable relative to a timer actuating passageway 39 formed in the body 21 by the rocking of the rotary valve plunger 27.

The timer mechanism for rocking the valve plunger 27 comprises an actuating cylinder 40 mounted on the main body 21 and having a head 41 forming with the body 21 an enclosed pressure chamber 42 communicating with the timer-actuating passageway 39. A passageway 43 is formed in the main body and has a throttle valve 44 rotatable by a control knob 45 to adjustably restrict or shut off flow through the passageway 43. Sealed into one end 46 of the passageway 43 is a Sylphon bellows 47 located in the pressure chamber 42 of the actuating cylinder 40. SEaled into the other end 48 is second opposing bellows 49 located in the open atmosphere. Sealed within the bellows 47 and 49 and the interconnecting passageway is a supply of viscous liquid 50 sufficient to fill one bellows when fully compressed and the other fully expanded.

An overcenter snap-action device between the rotary valve plunger and the bellows 49 comprises a yoke 51 fixed to the outer end of the bellows 49 and to the outer ends of which are connected tension springs 52 and 53 which are connected at their other ends to brackets 54 fixed to the actuating cylinder 40 so as to yieldingly normally hold bellows 49 in compressed condition and through the fluid 50 hold the bellows 47 expanded. An actuating arm 55 is fixed suitably to the yoke 51 and is pivotally connected at 56 to the outer free end of the overcenter trip lever 57 pivotally mounted in suitable bearings 58 in the actuating valve yoke 60 on the axis 59 of the rotary valve plunger 27. The yoke 60 likewise is journaled in suitable bearings 61 in the main body 21 and is fixed at 62 in the top of the valve plunger 27 to rotate the plunger 27 and rock about the axis 59. A tension spring 63 is connected between outer free end 56 of the overcenter trip lever 57 and the outer free end 64 of the valve actuating yoke 60. An appropriate artistic looking cover 65 may be applied over the entire above-described mechanism.

OPERATION

Once the unit is mounted on the can top, with the valve plunger 27 in the position shown in FIG. 6, as initially caused by the springs 52, fluid pressure from the can in passageway 36 discharges out through passageway 39 into the actuating cylinder chamber 42 compressing bellows 47, discharging fluid 50 into bellows 49 expanding the same, stretching springs 52 and 53 and finally snapping the overcenter members 57 and 60 to the position shown in FIG. 2, repositioning the valve plunger from FIG. 6 position to FIG. 5 position.

Fluid pressure from the can is then blocked off from the pressure chamber 42 while at the same time allowing fluid in chamber 42 to be connected through valve passageway 37 to the nozzle 24 and under the retracting force of the springs 52-53 fluid 50 is squeezed out of bellows 49 back into the bellows 47 to expand it to cause the can spray fluid to be discharged from the chamber 42 and out through the nozzle 24.

By appropriately adjusting the knob 45 to restrain or shut off interflow of the fluid 50 between the bellows 47 and 50, the length of the above cycle or arresting of the operation may be obtained.

Claims

I claim:

1. A pressure-powered aerosol timer for an aerosol can comprising in combination:

A. a main body including means for mounting the same on the top of the aerosol can,

B. an operable control valve in the body,

C. means for connecting fluid pressure from the aerosol can to the control valve,

D. a nozzle on the body,

E. means for actuating the control valve so as to automatically intermittently connect or shut off fluid pressure from the can to the nozzle including,

F. an actuating device operated by fluid pressure from the can and connected to operate the control valve,

G. means in the control valve effective when operated to one position to connect fluid from the can to the nozzle,

H. and further means in connection with the control valve to yieldingly normally move the control valve to a position to connect fluid pressure from the can to the actuating device,

I. an actuating cylinder on the main body,

J. a first bellows mounted on the main body within the pressure chamber of the actuating cylinder,

K. a second bellows mounted on the main body in open atmosphere,

L. a passageway in the main body in communication with the interiors of both bellows,

M. a fluid, independent of the aerosol can fluid, confined within the interiors of the bellows and the connecting passageway,

N. a timer-actuating passageway in the main body communicating between the pressure chamber of the actuating cylinder and the control valve,

O. yielding means between the main and the second bellows to normally cause compression of the second bellows and expansion of the first bellows, and

P. means operatively connected between the second bellows and the control valve for actuating the control valve.

2. A pressure-powered aerosol timer as in claim 1 wherein said second bellows comprises a flexible chamber.

3. A pressure-powered aerosol timer as in claim 1 wherein the means operatively connected between the second bellows and the control valve comprises an overcenter snap-action linkage.