US 2678202 A
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H. B IMPROVEMENTS IN AND RELATING TO APPARATUS FOR GENERATING GAS Filed Aug. 3, 1950 i J .T
May 11, 1954 RAKE 2,678,202
[3 t ue, a. M
INVENTOR. Brain? !:\G. 3. BY
Patented May 11, 1954 OFFICE IMPROVEMENTS IN AND RELATING TO APPARATUS FOR GENERATING GAS Leslie Harold Brake, Christchurch, New Zealand Application August 3, 1950, Serial No. 177,442
Claims priority, application New Zealand August 3, 1949 7 Claims.
The present invention relates to a gas generat lng apparatus. More particularly, the invention relates to a gas generating apparatus in which air is delivered through distributing means in a closed vessel to bubble up through a volatile liquid in the vessel. The invention has particular reference to improvements in the constructional features of such gas generating apparatus.
Accordingly, it is an object of the present invention to provide a compact, portable, economical gas generating apparatus including a closed vessel to receive a volatile liquid, an air distributing means within the vessel and a unique and novel air pump operable in response to the discharge of the produced gas from the vessel.
, It is another object to provide in such a gas generating apparatus an economical construction as far as operation of the apparatus is concerned embodying a solenoid actuated bellows pump rapidly movable on its suction stroke under theinfluence of the solenoid and having a slow delivery stroke, and in which the movement of the bellows on its suction and delivery stroke controls the current supply to the solenoid.
It is a further object to provide in such apparatus a float controlled valve for maintaining the volatile liquid at a substantially constant level in the vessel.
It is an additional object to provide in such apparatus a by-pass conduit between the air conduit to the distributing means within the vessel and the gas outlet conduit from the vessel so as to provide for adjustment of the richness of the gas so as to compensate for variations in the gas mixture, such as variations resulting from the eifect of temperaturevariations on the volatility of the liquid.
The preferred form of gas generating apparatus according to the invention will now be described with reference to the accompanying partly diagrammatic drawings, in which: 1
Figure 1 is an axial section through an air or gas pump embodied with the apparatus of the invention, showing the actuating means therefor and a pressure equaliser associated with the pump outlet, some of the parts being shown in elevation,
Figure 2 is an enlarged elevation of the contacts and the operating means for the moving contact,
Figure 3 is a side elevation of a portable gas various features of the same, some of the parts being shown in elevation.
The apparatus includes a pump shown in Figures 1 and 2, comprising a substantially vertical bellows I, the upper end or head 2. of such bellows constituting the free end and being connected by a sleeve 2a to the core 3 of a highefficiency and low consumption electrical solenoid 4 mounted at a fixed position above the bellows. The base 5 of the bellows is also mounted at a fixed position on an upright A carried by a base B.
The electrical current supply to the solenoid 4 is controlled by a fixed contact 6 and a contact la on a bar i pivoted at 8 to a fixed member 8a, the contact la being adapted, for instance under action of a spring, to make electrical connection with the fixed contact 6, thus completing the circuit in known manner and so causing the solenoid 4 to become energised;
A condenser 6a of suitable capacity is connected across the two contacts 6 and la to minimise arcing.
A cam or eccentric I0 is pivoted at 9 to a fixed member such as the member 8a and. engages and bears against a fibre block lb carried by the contact Ia, such cam lil having an arm ll adapted to be engaged or tripped by a pair of stops or projections I2 and I3 fixed at a suitable interval apart to the sleeve 2a associated with the core 3 so that the stops or projections move with the core.
The arrangement is such that, when the head 2 of the bellows reaches its lower position at the end of its useful pumping stroke, performed as here shown by gravity due to the loading provided by the weight of such head and that of the core 3, the upper stop l2 trips the arm i I and depresses the latter to a position as shown in Figures 1 and 2, in which it causes the cam ID to present a minor radius portion of its eccentric working face to the block (b on the contact bar I, with the result that the contact 1a establishes electric connection with the fixed contact 6.
When this takes place, the solenoid 4 becomes energised and so raises the core 3 to its upper position, as indicated in Figure 1 by dotted lines.
The upward movement of the core 3 serves to raise the conneetedupper end or head 2 of the bellows, with the result that the fluid being pumped is drawn into the interior of the latter through ports I4 controlled by a lightly springloaded non-return inlet valve I 4a faced with rubber or the like, this constituting the suction or return stroke of such bellows.
As the core 3 approaches its upper position, the
,circuit through the solenoid 4, whereupon the in which are located a control valve 34a operated manually or thermostatically from the tempera ture of the liquid in the vessel 22.
To shield the float valve from the flocculent material, that is; to prevent the packing material 7 26 from coming in contact with and impeding beneath the base 5 of the pump bellows Land.
the base 5 in order to provide suitable loading for such equaliser to maintain its, contained fluid-e, g. air at a suitable substantially constant pressure and so substantially obviate supply-line pressure pulsations produced by the action of the pump 1.
Referring now to Figures 3 and 4 of the drawings, wherein is shown gas generating apparatus embodying the pump shown in Figures 1 and 2 for passing air through a suitable volatile liquid to produce gas, the air from the pump bellows l is delivered through the equaliser i5 and pipe ii and through distributing means having an annular distributing passage 2| perforated on its underside intothe lower part'of a gas generator vessel 22 consisting of a closed vessel to which thevolatile liquid is fed through a valve controlled pipe 226 from a reservoir 22a under control of afloat 23 controlling a needle-valve 24 whereby such liquid is maintained at a substantially con'stant level in, the generator vessel 22. The passage 2! isdisposed below the level of the liquid in the vessel.
The'arrangement is such that the air is ejected through the apertures in the lower part of the distributing passage 2! and is bubbled through the liquid in thevessel 22, producing a gas in the upper part of the latter from whence such gas is led by 'a pipe 25 to supply heating or lighting burners, preferably of the Bunsen type, or to dis- 4 charge the gas for any other suitable purpose.
To ensure sufiicient richness of the gas, the vessel 22 is packed with steel or brass wool, cotton waste or other suitable flocculent material 26 to make the path of the air bubbles through the liquid more tortuous, thereby bringing such air into more intimate contact with the liquid. This is an important feature of the invention where the invention is in use under lower temperature conditions.
In order to allow for variations in the richness of the gas .mixture leaving the vessel, for instance where the fluctuations are due totemperature fluctuations, the apparatus can be designed to produce a rather rich mixture an'dan auxiliary air supply can be taken from the pipe I! to the pipe 25 by wayof a'bye-pass pipe 3 4 (Figure 4) the-movements of the float 23 and its needle valve 2t, such parts 23 and 24 are enclosed in an inner chamber'Zl disposed in the vessel 22 and in the bottom of which is a hole 23 communicating with theinterior of the vessel, to permit the liquid to flow into the interior of the vessel 22, while near the upper end of such chamber 2'l is a hole 29 providing a vent-"for gas to pass from the chamber Z 'i to the vessel 22.
;The external surface of the vessel 22 is formed with ribs or fins 30 to increase its area in contact" with the atmosphere and so prevent an undue fall of temperature from occurring in such vessel as the result of the evaporation of the liquid therein.
To ensure the maximum of eificiency the armature or core 3 is preferably made of an appropriate ferrous material of such dimensions that at no stage is magnetic saturation reached. For the same reason the solenoid is preferably ironcladthat is, a return path for the magnetic field is provided through a casing 4a of suitable ferrous metal covering the outside of the winding.
ilhe apparatus of Figure 3 constitutes a compact and portable gas generating apparatus in which the horizontal base B has mounted thereon the upright A. A carrying handle 35 is provided so that the apparatus can be easily lifted and carried around to its desired location since the particular pump structure occupies small dimen- 'sions, the entire apparatus encompasses a crosssectional area of relatively small dimensions. As shown in the drawing, the volatile liquid receiving reservoir 22a is carried by the upright near the top thereof and the gas generating tank or vessel 22 is supported by this upright subjacent the reservoir. The liquid feed pipe 221) provides communication between the reservoir and the generating tank under combined control of the manually operable shut-oi? valve 22c and the float control valve 24. As indicated in Figure 4, the gas generating vessel or tank includes the externally ribbed tank having upper edges and a removable top 35. The top has a depending marginal flange which, when the top is in posi tion, projects downwardly below the uppr edge's of the tank 22. The inner chamber 21 constitutes a combined liquid receiving and float containing chamber and includes a lateral extending flange 36 which rests on the upper edge of the tank 22 and is held thereagainst when the top 35 which i removable is clamped thereon. To eifect this clamping action a headed bolt member 31 passes through an aperturein the bottom of the tank 22 and includes a threaded portion which receives a nut 38 against which rests the bottom of the chamber 21. The upper extremity of this bolt 31 is likewise threaded -so that when its upper end passesth'rou'gh a central aperture in the top 35, a nut 39 threaded on to this bolt clamps the top 35 to the flange 38 resting on the upper edges of the tank 22. As indicated, the space between the sidewalls of the chamber 2'! and the tank-12 is the gas receiving space and the gas delivery pipe 25 communicates with the top 35 near the periphery thereof so as to be in communication with this gas receiving space. The distributing member '21 I eifecltively introduces air in a "downward direction into the liquid fromwliehcethe gas generated bubbles upwardly through the floceulent material 26 and the liquid and thence into the gas receiving space.
i The liquid employed may be any suitable liquid fuel with an appropriate low boiling range-i'or example between 30 C. and 60 C. In operation, the appropriate liquid is introduced into the reservoir 22a and assuming the valve 22c to be open the liquid will flow by gravity under float valve control into the vessel 22 until the normal operating level is reached, the fuel being automatically kept substantially. at this level by the float valve during operation.
Assuming the electrical power to be switched on and the pump head to be in its lowest position, with the contacts 6 and la closed, the solenoid will be energised, thereby raising the core 3 and the head or the pump. The upward movement of the head 2 of the pump is so rapid that the inertia of the mass of the valve la. is not overcome by the valve spring, and consequently the ports M are opened to the influx of air into the pump; This is assisted by the use of only a light spring on the valve Hid, and the effect of this action is to ensure ready opening of the said valve and consequent reduction of load on the pump and low consumption of electrical energy.
As the core approaches its upper position, the mechanism operates to open the contacts 6 and la and assuming that the operating pressure has not already been built up, the pump head 2 sinks by gravity, ejecting the air through the ports 16 into the pressure equaliser from whence it travels through the pipe I! and distributing passage 2! to bubble upwards among the nocculent material and through the liquid, thus forming a gas in the upper part of the vessel 22 from which the said gas is taken away through the pipe 25 as desired. As the pump head approaches its lowest position the contacts 6 and la are again closed.
The pumping action is automatic during discharge of gas from the vessel 22, and ceases whenever the normal pressure has been built up, whereupon the pump head ceases to move by gravity and the electrical circuit remain open. Electrical power is only consumed during the return or suction strokes, and it will be appreciated therefore that when the flow of gas from the generator ceases, as the result of the closing of a tap in the outlet pipe 25 or on a burner or other appliance connected with such pipe, no electrical power will be consumed.
The apparatus may be designed to build up a working pressure of a degree similar to that employed for conventional gas fuelled domestic appliances.
Should the needle valve stick and admit liquid when the liquid level in the vessel 22 is already sufficiently high, the tap 32 can be used to drain away the surplus.
When desired, any foreign matter such as water of condensation can be drained away through the plug controlled outlet 33.
The inverted arrangement of the distributing passage 21, i. e. with its outlet apertures in its lower side, ensures that the said passage can be kept substantially free of liquid, and consequently assists in maintaining substantially even upward air flow through the liquid in the vessel 22.
The pointed upper end of the solenoid core 3 has been found in practice to give substantially even magnetic pull on the core throughout its stroke which may for example be about two inches.
The electric power necessary to energise the solenoid may be obtained from any small source of direct current, such for instance as a battery of 6, 12, 24 or 32 volts (which may be an existing car battery or a bash lighting battery) By the provision of the equaliser [5, the air supplied to the generator vessel 22 will be maintained at substantially constant pressure and consequently such generator will supply gas at constant pressure to the burners.
Referring to Figure 3 of the drawings, the air delivery pipe ll between the pump bellows l and the vessel 22 extends upwards above the normal level of the liquid in the reservoir 22a, in order to prevent back flow of liquid to the pump in the event of the vessel 22 flooding, such as through the needle valve sticking or leading.
The gas delivery pipe 25 extends upwards to a level higher than the normal liquid level in the reservoir in order to prevent overflowing of liquid through the outlet in the event of the vessel 22 flooding.
The method of operation may be substantially the same whether the gas is a combustible gas for burning, or whether it is any suitable form of gas for any other purpose such as fumigating.
Alternatively to, or in addition to, the loading means for the pump as constituted by the gravity operation of the pump bellows l, the said pump bellows may be spring-loaded in a manner similar to the equaliser it, or other resilient means such as a rubber band may be employed, the spring or other resilient means operating the pump in its useful stroke.
While modifications in structure can be made it is understood that the invention is not to be limited other than by the scope of the appended.
What is claimed is:
l. A compact portable gas generating apparatus comprising a supporting means, a. carrying handle embodied therewith, a volatile liquid reservoir supported by the supporting means, a separate gas generating tank supported by the supporting means subjacent said reservoir and including upper edges and a removable top, a, gas delivery pipe communicating with the tank through said top, a combined liquid receiving and float containing chamber including side walls and an apertured bottom supported within the upper portion of said tank with the bottom of the chamber spaced from the bottom of the tank, a liquid feed pipe communicating with. the reservoir, passing through the top of the tank and terminating in spaced relation to the bottom of said chamber, a float within said chamber, a valve carried by said float and cooperable with said feed pipe to control liquid flow therethrough and thus flow from said reservoir to said chamber and thence to said tank responsive to the position of said float to maintain a substantially constantly constant liquid level in said chamber and tank, an air inlet pipe communicating with said tank subjacent the bottom of said chamber, and an air distributing member extending from said inlet pipe, disposed within the tank and having delivery apertures on the under side thereof so that air can flow downwardly into and upwardly through the volatile liquid to generate gas therefrom with the gas rising through the. liquid into the space above the liquid level and between the side walls of the chamber and the tank for delivery through said gas delivery pipe.
2. A compact portable gas generating apparatus as defined in and by claim 1, in which the side walls of said chamber have a laterally extending: flange supported on the'upper edges: of. said: tank and: means clamping the top. tovthe tank; to? thereby clamp the chamber in supported. position within the tank.
. 3. A compact; portable gas. generating apparatus comprising asupporting means including a. base and; any upright and. a carrying handle embodied therewith, a. volatile liquid reservoir supported by theupright, aseparate gas generating tank supported by the; upright subjacent said reservoir and; including a top.,.a gas delivery pipe communicating with the. tank through said top,
a combined. liquid receiving. and float containing chamber including: side walls and an apertured bottom supported within. the upper portion. of said tank with the: bottom of the chamber spaced fromthe bottom of the. tank, a liquid feed pipe communicating with the. reservoir, passing. through. the. top of. the tank and terminating in spaced. relation to the bottom of said chamber, a float within said chamber, a valve carried. thereby andcooperable with the said feed pipe to control flow-therethrough, an air inletpipe. communicatingwith said tank subjacent the bottom of said chamber, an air distributing member extending from'said inlet pipe disposed withinthe chamber and having delivery apertures on the under side thereof so that air can flow downwardly into and upwardly through the volatile. liquid to generate gas. therefrom. with. the gas rising through. the liquid. into the. s ace above the liquid level and between. the side walls. of. the chamber and the tank, said air inlet pipe including a portion extending above said tank, and a valve controlled bypass extending. between said portion and said gas delivery pipe,v a valve in said bypass controlling gas flow from said inlet pipe to said delivery pipe to adjust the richness of the gas mixture flowingthroughsaid delivery pipe.
. "4. A compactlportable gas generating.- appa ratusas. defined in andsby claim. 1, and a floccu-' lent mass within the tank. to provide a tortuous passage: for theair through the liquid to: increase the richnessof' the mixture.
5. Apparatus as claimed in. claim 4, wherein the external surface of the vessel is ribbed. in order to. minimize the drop in. the temperature-of: thecontents of the vessel during use.
6; Apparatus as claimed. in claim 1, wherein a drain tap is provided abovethe liquid levelin" the vessel;
7. Apparatus as, claimed in claim. 3, wherein. the air inlet pipe includes a portion extending above the maximum liquid level of the tank andthe-gas delivery pipe includes aportion extend-- ing above the maximum liquid level of thetank.
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