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Publication numberUS2840101 A
Publication typeGrant
Publication dateJun 24, 1958
Filing dateNov 23, 1956
Priority dateNov 23, 1956
Publication numberUS 2840101 A, US 2840101A, US-A-2840101, US2840101 A, US2840101A
InventorsSaylor Arthur D
Original AssigneeSaylor Arthur D
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Plumbing system
US 2840101 A
Abstract  available in
Images(3)
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Claims  available in
Description  (OCR text may contain errors)

3 Sheets-Sheet 1 i f, J

INVENTOR. 4227/ /02 .0. SQVLOe 2W firmZA/EZ June 24, 1958 Flled Nov 23 1956 June 24, 1958 A. D. SAYLOR 2,340,101

PLUMBING SYSTEM Filed Nov. 23, 1956 3 Sheets-Sheet 2 T INVENTOR. 1% flew/we 0. Spy 40a em/v.5 66 P26. 5

United States Patent PLUMBING SYSTEM Arthur D. Saylor, Los Angeles, Calif.

Application November 23, 1956, Serial No. 623,757

17 Claims. (Cl. 137335) This invention relates to an arrangement for the distribution of water in building or vehicle constructions, and more particularly to a plumbing system for isolated rural dwellings such as vacation cabins and/or mobile housing units or housetrailers which require their own independent water sources as distinguished from those using only the common water supplies of municipalities.

For example, in vacation cabins which may be used only from one to four weeks out of the year, the only practical way to obtain pumped water at a tap is to employ an electric motor driven pump when electricity is available or to employ a gasolene engine driven pump when electricity is not available. The use of a pressure accumulator is also generally necessary. However, the purchase of all this equipment amounts to a sizeable investment which is not substantially rewarded because vacation cabins are used so little and so infrequently. Furthermore, this same problem and a great many more are encountered in the use of housetrailers.

Several of these other problems arise specifically in relation to a flash type water heater which is generally employed in a housetrailer, i. e. a water heater having a pilot light burner, a main burner, a butane tank, and a gas valve connected between the butane tank and the main burner operative in response to a drop in pressure in an associated water line to turn the main burner on when a tap in the water line is opened. Thus, when a tap is opened, the pressure drops in the line and the main burner is turned on.

The use of a flash water heater is generally deemed an unusually convenient expedient in a housetrailer as is the use of an airtight pressure tank which is normally employed to circulate water from a reservoir to a tap in the trailer when urban water supplies are not available. However, the use of a pressure tank has one particular extremely serious disadvantage. Specifically, a plumbing system must be established for the pressure tank water supply which is entirely independent of an alternative urban supply inlet. This for the reason that reduction in pressure within the pressure tank may cause the main burner of the flash water heater to be turned on by the pressure switch and the plumbing system then might thereby be rendered explosive since water would not be circulated in this case. Still further, live steam may be generated in the heating coils of the water heater and thereby create an extremely hazardous condition both to the person and property of the housetrailer inhabitants.

Several disadvantages that accompany the employment of the dual plumbing systems required in the use of pressure tanks will, of course, be obvious; however, to the present time, no satisfactory substitute has been developed. Furthermore, the use of the pressure tank has several other disadvantages. In the first place, the pressure tank is bulky, it is heavy, and it is very expensive. The fact that the pressure in a tank decreases as it is used makes it inconvenient to use; an initial high standing pressure plus vibration which is a natural result of mov- 2,840,101 Patented June 24, 1958 Ct: ing a housetrailer makes the trailer and plumbing system both very susceptible to damage; and, in addition, the pressure tank is very ditficult to disassemble and to get water from in the event that the plumbing system somehow becomes plugged.

It is therefore an object of the invention to provide a small plumbing system, light in weight, which may be installed and maintained in a building construction of mobile housing unit at low cost.

It is still another object of the invention to provide a safe plumbing system which may be used with a flash water heater both in rural and urban areas.

Yet another object of the invention is to provide a plumbing system having a power supply having a small varying pressure difierential for any demand within a predetermined range and having a pressure dilferential substantially changing with use.

A further object of the invention is to provide a plumbing system requiring no high pressure inputs or outlets for use in both rural and urban areas.

A still further object of the invention is to provide a plumbing system for use alternatively in both urban and rural building constructions or mobile housing units which may be easily and quickly disassembled and thereby easy to maintain and to obtain water from.

The present invention achieves these and other objects and advantages by providing a reservoir to hold water, pump means connected from the reservoir to maintain a substantially constant outlet pressure regardless of demand, a first valve connected from the pump means to permit flow of water only out of the reservoir, an alternative inlet having means to close it connected to the output side of the first valve, an electric motor to drive the pump means, a source of potential, means including an electric switch to connect the source to the motor, a tank to hold the combustible gas, a hot water valve, a flash water heater having a conduit therein connected from the output side of the first valve to the hot water valve, a hot water outlet connected from the water valve, a cold water valve, a cold water conduit connected from the output side of the first valve to the cold water valve, a cold water outlet connected from the cold water valve, the flash water heater having a main burner inlet and a pilot light burner inlet, a gas valve connected between the tank and the main burner inlet, the pilot light outlet being connected to the tank through a pilot light conduit separate from the gas valve, and manually operable mean to open and close the gas valve.

Preferably the pump means includes a centrifugal pump to maintain water pressure at the outlets of each of the hot and cold water valves substantially constant without regard to the demand on the pump. That is, the hot and cold water valves may both be shut ofi without overloading the electric motor, although the pressure will not drop substantially when the valves are open, i. e.

only an amount sutficient to cause the main burner of the flash water heater to ignite. For such a small plumbing system, it thus can be seen that the apparatus may be madelight in weight and otherwise convenient to use. It is also substantially less expensive than the air pressure tank installation as previously described both in initial cost and in maintenance. Furthermore, no excessive pressures need be employed since the pump may produce a maximum pressure of 15 pounds per square inch and a minimum pressure of l3 pounds per square inch in normal use. Still further, the use of the electric lamp serially connected with the motor and the motor switch may be employed inside a dwelling or housetrailer as the case may be to warn that the manually operable means, which may be a knob to operate the gas valve, should be operated to turn the flash water heater olf. This could only be done if, as in the instant case,

3 an electric motor were used. It is to be noted that no inconvenient fluctuating pressure is created by a centrifugal pump driven by an electric motor as would be in the case where an air pressure tank were used. Still further, no high standing pressure is created, thus damage to the system due to vibration in a housetrailer is eliminated. Moreover, the system is extremely easy to maintain, and. a simple tap can be employed at the bottom of a reservoir to tap off water in case any part of thesystem becomes inoperative.

Other objects and advantages of the present invention will be better understood when considered with the following description taken in connection with the accompanying drawings made a part of this specification, where in several embodiments are illustrated by way of example. The device of the present invention is by no means limited to the specific embodiments'illustrated in the drawings since they are shown merely for purposes of description.

Fig. l is a perspective view of the plumbing system of the invention in a housetrailer shown in phantom;

Fig. 2 is a broken away elevational view of a centrifugal pump and electric motor employed in the plumbing system of the invention;

Fig. 3 is a transverse sectional view of the centrifugal pump taken on the line 33 shown in Fig. 2;

Fig. 4 is a transverse sectional view of the motor coupling taken on the line 44- shown in Fig. 2;

Fig. 5 is a diagrammatic view of one embodiment of the invention; and

Fig. 6 is a diagrammatic view of still another embodiment of the invention.

In the drawing in Fig. l, a trailer 10 is indicated in phantom housing a plumbing system indicated generally at 12. The plumbing system is provided with a sink 14 having a drain 16 into which water is conveyed by means of a cold water outlet 18 and a hot water outlet 20.

Water is stored in the trailer lit) in a reservoir 22 having an inlet covered by cap 24 and having two outlets 26 and 23, both of which are shown only in Figs. 5 and 6, outlet 28 simply being a tap, and outlet 26 being simply a conduit to a centrifugal pump 3 which is driven by an electric motor 32.

Pump 3%) pumps water from reservoir 22 upwardly through a check valve 34, two pipe T5 36 and 33, and thence through both a water heater 4d and a conduit 42 to a cold water valve 44 connected to outlet 18. The hot water output of heater 4-9 is then passed through a pressure switch 46 and thence through a pipe 48 to a hot water valve 51 which is connected-to hot water outlet 2"). Pipe T 36 provides passage to both cold water valve E-d and to the water input side of heater 40 and so provides an alternative inlet 52 having manually operable means or simply a hand valve 54 connected serially with it to close it during the operation of pump 30 or to open when water from urban areas is used in a trailer park or the like. Heater 40 is supplied with gas by means 56 including a pipe 58 and a hose 60 connected together by means ofa coupling 62. A' hand operable gas valve 64 is then connected serially with pipe 53 as is a second gas valve- 66 preferably operable in response to actuation of pressure switch 46. Hose 65) preferably extends to a location outside the trailer 19 to a tank 68 of a combustible gas such as butane.

A though the electric motor 32 and other of the elec-' trical apparatuses in the plumbing, system of the inven-' serially with the output of the positive terminal 74 of battery-79. 7 V

Alsorconnected to the fuse plate 76 is an input lead 80 foriningythe' secondjof a pair includingan input lead 82 which is grounded of a plug 84 which may be employed as a source of potential when an outside power supply is provided or when the power of an automobile battery is used.

It is to be noted further that a flue 86 is provided atop of the heater 40 to prevent noxious fumes and the like from filling the interior of the trailer body.

As shown in Fig. 2, motor 32 preferably includes a housing 88 having output leads 96 connected therefrom, the housing being mounted on a supporting bracket 92 by means of studs 94 welded to the housing 88 and extending through apertures 96 and being threadedly engaged by nuts 98 to fix motor 32 to bracket 92. Motor 32 is also provided with a shaft 1110 which extends into a coupling 1432 which may be flexible if desired. Coupling 192 is then fixed to shaft 104 of centrifugal pump 30.

Centrifugal pump 30 is provided with an input pipe 196 and an output pipe 168, input pipe 106 being connected to an input plate and output pipe 108 being connected to an output casting 112.

Plate 110 is fixed to casting 112 by means of screws 114 which engage threaded portions 116 and ears 118 of casting 112. This with a centrifugal pump rotor 120 can be seen best in Fig. 3. The rotor 120 is preferably spaced from the internal periphery of the casting 112 as shown in Pig. 3 and may be made of brassas may the casting 112 and plate 110.

As can-be seen in Fig. 4, bracket 92 is provided with a tubular portion 122 enclosing coupling 1%2 which is provided with a pair of longitudinal recesses 124 to receive longitudinal projections 126 of shaft 190. Use of studs 94 and 98 thereby makes assembly of a new motor on bracket 92 a simple matter.

p All the structure described in connection with Fig. 1 is shown in Fig. 5 in a schematic form. However, some additional structure is shown in this figure including an electrical switching arrangement. Specifically, the pressure switch 46 includes a pipe key 128 which provides f and open communicatiou from the water output heater to hot water valve 5%) and to a bellows or diaphragm 13% which is employed to operate a switch connected from the positive terminal '74 of battery "iil'to one side of a solenoid 13 2, the other side of which is grounded. Sole noid 134 then opens gas valve 66 when the pressure in the pipe tee increases to a value adequate to prevent steam from being generated in coilsof the heater 4%.

Pressure switch 419i5 not connected as it is normally in a flash water heater. This for the reason that motor 32 turned only when water is desired-at outiets 1 and Specifically, cold water is obtained by simultaneously opening valve 54 by turning a manually. operable handle 136 to' simultaneously close a switch 133 which operates motor 32 by connecting one side of the motor 32 tothe positive terminal 74, the other side of the motor 32 being grounded.

Hot water is obtained by opening valve 50 by turning manually operable handle 140 and thereby simultaneously opening gas valve 64 and closing a switch 142 to run motor 32. Heater 4% is provided with a pilotlight 144 which bypasses both valves 64 and 66 from conduit 56 connected to butane tank 68; A main burner 146 is also provided for heater 49, the main burner 146 being supplied only through both valves 64 and 66. 7

As also shown in Fig. 5, manually operable means 148 are preferably provided to operate both valve 54 and a switch 150 which is preferably normally closed when valve 54 is closed. The purpose of this and the connections of switches 132, 138 and 142 will be explained' venience. However, switches 138 and 142 are operable simultaneously with valves 44 and 50, respectively, by movement of arms 136 and 140 simply as a matter of convenience. However, operation of gas valve 64 with arm 140 prevents any lighting of main burner 146 in the absence of water in conduit 48. This means that no steam can be generated in the heater 40. Furthermore, even if the motor 32 or the pump 30 fails, gas will not be supplied to main burner 146 because water pressure will not cause switch 132 to close.

The use of normally closed switch 150 is made to prevent the energization of motor 32 by the turning of bars 136 and 140 when water from a trailer park is used and pump 30 is no longer required, valve 54 in this case being opened by operation of means 148.

As shown in Fig. 6, a flash water heater 152 may be employed including a conventional pressure switch 154 including a pipe tee 156 having a bellows 158 connected therefrom to operate a normally open switch 160 and thereby solenoid 134 to open valve 66 when pressure in conduit 48 drops due to opening of valve 50 by operation of arm 140.

In this case, it is to be noted that valves 44 and 50 are conventional and have only one operative arm 136 and 140, respectively, which are not employed to operate any other switch. In this case, motor 32 is turned on by means of a switch 162 operative in response to movement of an arm 164. In this case, motor 32 runs continuously for a predetermined length of time during which continual use of hot and cold water outlets 20 and 18 is expected. A lamp 166 Which preferably is located to be visible to the inhabitants of the trailer is then connected serially with motor 32 and battery 70 to indicate that motor 32 is running. In this case, should motor 32 fail, valve 64 may be turned off and thereby prevent heater 40 from creating steam in conduit 48 and the coils in it. Preferably arm 164 is provided to open valve 64 and close switch 162 simultaneously to prevent ignition of main burner 146 of the flash water heater 152 when no pressure differential exists between atmospheric and the pressure in conduit 48, this condition occurring when motor 32 is not running. This prevents one from opening switch 162 without turning oif valve 64. It is to be noted further that a plug 168 is provided for conduit 52 to close it when reservoir 22 is in use.

By virtue of the fact that the plumbing system shown in Fig. 6 may be employed with the flash Water heater 152, a dual system for an outside water supply, water to be introduced in conduit 52, may be employed without the necessity of providing alternative inputs to flash water heater 152. As a practical matter, as stated previously, flash water heater 152 may not be employed with the air pressure tank now conveniently used as a pressure supply in rural or in locations Where water is not supplied under pressure.

It therefore can be seen that the reservoir or water tank 22 may be made of a light material since it need not withstand any great pressure. Furthermore, pump 30 and motor 32 may be exceedingly small and inexpensive. The whole system is therefore not subject to a high initial cost or a high maintenance cost. In addition, use of flash water heater 152 with arm 164 operating the valve 64 and switch 162 simultaneously makes it impossible for the heater to operate unless motor 32 is turned on. Still further, lamp 66 enables one to determine whether or not motor 32 is in fact operating and therefore water exists in conduit 48. By virtue of the fact that pump 30 is a centrifugal pump, in the embodiment of the invention in Fig. 6, pressure may exist in conduits 92 and 48 continuously over a period of time requiring the use of hot or cold water. Motor 32 thereby not being overloaded when both valves 50 and 44 are turned off and motor 32 is kept running.

As stated previously, centrifugal pump 30 provides a pressure which varys very little in conduits 92 and 48,

e. g. from 15 to 13 pounds per square inch, or from zero to full demand. This small fluctuation in pressure is of course no inconvenience. Further, the lack of high pressure in any of the lines decreases the likelihood of dam age by the use of pressure in lines in a mobile housing unit such as the trailer 10 which is subject to vibrations during traveling time. Furthermore, motor 32 and thereby pump 30 may be turned off when the trailer 10 is actually being moved. This, of course, is not the case with an air pressure tank. It is to be noted still further that tap 28 is provided, whereby water may be obtained conveniently from reservoir 22 although this may not be the case if an air pressure tank filled with water were used.

In Fig. 5, it is to be noted that preferably valve 34 is a check valve, although it may be manually operable with means 148.

According to one aspect of the invention, the pressure switch 46, different from pressure switch 154 of the prior art and as shown at 46 in Fig. 5, is preferably employed with water heater 40 including pressure sensitive means or bellows connected between hot water valve 50 and the hot water output of heater 40 to operate gas valve 66 via solenoid 134. In this case gas may be permitted to flow to the main burner 146 when the pressure of the Water line between heater 40 and hot water valve 50 increases to a predetermined valve. As explained previously, flash water heater 152 shown in Fig. 6 is of the conventional type and the connections of heater 40 with pressure switch 46 and the intermediate connections are a modification thereof. The usual connection of pressure switch 46 as distinguished from the conventional pressure switch 154 is only employed in the case where the electric motor is turned on each time water is wanted. At this point, it is pertinent to note that check valve 34 may be employed to prevent any water from flowing back toward the water tank 32 and with the hot and cold Water valves 50 and 44 respectively will keep water in the line and therefore make it always available. This makes it unnecessary to wait for the electric motor to run a length of time suflicient to cause the pump to pump water up to the hot and cold water outlets 20 and 18 respectively which will generally be spaced above water tank 22 as indicated in Fig. 1, although they may be spaced below it.

Although only two specific embodiments of the invention have been shown and described, many other changes and modifications of the invention will be obvious to those skilled in the art and therefore may be made without departing from the true scope of the invention as defined in the appended claims.

What is claimed is:

1. A plumbing system comprising: a reservoir to hold water, pump means connected from said reservoir to maintain a substantially constant outlet pressure regard less of demand, a first valve connected from said pump means to permit flow of water only out of said reservoir, an alternative inlet having means to close it connected to the output side of said first valve, an electric motor to drive said pump means, a source of potential, means including an electric switch to connect said source to said motor, a tank to hold combustible gas, a hot water valve, a flash water heater having a conduit therein connected from the output side of said first valve to said hot water valve, a hot water outlet connected from said hot water valve, a cold water valve, a cold water conduit connected from the output side of said first valve to said cold water valve, 21 cold water outlet connected from said cold water valve, said flash water heater having a main burner inlet and a pilot light burner inlet, a gas valve connected between said tank and said main burner inlet, said pilot light outlet being connected to said tank through a pilot light conduit separate from said gas valve, and manually operable means to open and close said gas valve. I

2. The invention as defined in claim 1, wherein said pump means is a centrifugal pump.

3. The invention as defined in claim 1, whereinsaid manually operable means is adapted to open said gas valve and to close said electric switch jointly, said marl-- ually operable means being adapted to close said electric switch first.

4. The invention as defined in claim 3, wherein an electric lamp is connected serially with said switch.

5. The invention as defined in claim' 1, whereinan electric lamp is connected serially with said switch.

6. The invention as defined in claim 1, wherein said first valve is a check valve.

7. The invention as defined in claim 1, wherein a tap is connected from the bottom of said reservoir, whereby water may be drained therefrom in the event that said motor or said pump becomes inoperative.

8. The invention as defined in claim 1, wherein a second switch is serially connected with said electric switch, and wherein said means to close said alternative inlet includes a second valve, second manually operable means to operate said second valve simultaneously with said second switch, said second switch being normally closed when said alternative inlet valve is closed, said second manually operable means being adapted to open saidalternative inlet valve and said second switch simultaneously.

9. The invention as defined in' claim 8, wherein said pump means is a centrifugal pump; wherein said first mentioned manually operable means is adapted to open said gas valve and to close said electric switch jointly, said manually operable means bein adapted to close said electric switch first; wherein said first valve is a check valve; and wherein the following are additionally provided: an electric lamp connected serially with said electric switch, and a tap connected from the bottom of said reservoir, whereby water may be removed therefrom in the event said pump or said motor becomes inoperative.

10. A plumbing system comprising: a reservoir to hold water, a pump connected to said reservoir, a first valve connected from said pump to permit the flow of water only in a direction away from said pump, an alternative inlet connected to the output of said first valve, meansto close said alternative inlet, an electric motor to drive said pump, a source of potential, a first switch to connect said source to said motor, a second switch connected in parallel with said first switch, a tank to hold a combustible gas, a water heater having .a water conduit therein connected from the output side of said first valve, a cold water valve, a cold water conduit connected from the output side of said first valve to said cold water valve, 21 cold water outlet connected from said cold water valve, a hot water valve connected from the output side of said water heater, a hot water outlet connected from said hot water valve, said water heater having a main burner inlet and a pilot burner inlet each inlet being connected to saidtank, a first gas valve connected serially only with said main burner inlet, hot watermanually operable means to open said hot water valve and said-first gas valve and to closesaid first switch all simultaneously,

and cold water manually operable means to open said cold water valve and to close said second switch both simultaneously.

11. The invention as defined in claim 10, wherein' said pump is a centrifugal pump.

12. The invention as defined in claim 10, wherein an electric lamp is connected serially with said switches.

13. The invention as defined in claim 10, wherein said first valve is 'a check valve.

14. The invention as defined in claim 10, wherein a tap is connected from the bottom of said'reservoir, whereby water may be drained therefrom 'in the event that said motor or said pump becomes inoperative.

15. The invention as defined in claim 10, wherein said means to close said alternative inlet includes a valve, secondmanually operable means to operate said valve simultaneously with a switch serially connected with said electric switch, a third switch serially' connected with said electric switch, said third switch being normally closed when said alternative inlet valve is closed, said second manually operable meansbeing adapted to open said alternative inlet valve andsaid third switch simultaneously. 7

16. The invention as defined in claim 10, wherein a second gas valve is connected between said first gas valve and said main burner inlet, and means connected between said water heater and said hot water valve to open said second gas valve when the water pressure in said water heater drops due to the opening of said hot water valve.

17. The invention as defined in claim 16, wherein said pump means is a centrifugal pump; wherein said manually operable means is adapted to open said' gas valve and to close said electric switch jointly, said manually operable means being adapted to close said electric switch first; whereinsaid first valveis a check valve; andwherein the following are additionally provided: an electric lamp connected serially with said electric switch, and a tap connected from the bottom of said reservoir, where- .by water may be removed therefrom in the event said pump or said motor becomes inoperative,

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Referenced by
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US2977025 *Aug 8, 1957Mar 28, 1961Westinghouse Electric CorpWater dispenser
US3073646 *Mar 31, 1961Jan 15, 1963Garrison Sr Eugene PKitchen trailer
US3776261 *May 15, 1972Dec 4, 1973Houghton CWater conserving apparatus
US3811462 *Jun 8, 1972May 21, 1974Feliz JRecreational vehicle utility stowage and transfer system
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US4092085 *Oct 7, 1976May 30, 1978Aqua-Marine Mfg. LimitedFaucet assembly
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US4286617 *Feb 8, 1979Sep 1, 1981John SwanWater system freeze protection apparatus
US4332681 *Apr 28, 1980Jun 1, 1982Jambry Jean FrancoisJunction and connection terminal for the service of fixed or mobile premises in particular for the supply of a sanitary unit which may be itself attached to a caravan or a camping-car
US4491150 *Nov 30, 1981Jan 1, 1985Carroll HolmanOutdoor water holding and pumping system
US4652041 *Apr 30, 1984Mar 24, 1987Barber Gerald LMobile living quarters
US4776631 *Jun 5, 1986Oct 11, 1988Thetford CorporationSelf-contained RV sanitary systems
US5039007 *May 26, 1989Aug 13, 1991Wolter Gerald CWater and air heating system
US5111626 *Oct 22, 1990May 12, 1992Fortune Jeffrey LSelf-contained modular unit
US5538031 *Dec 26, 1995Jul 23, 1996Brence; Shelby J.Recreational vehicle winterizing device
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US6250336 *Jan 22, 1999Jun 26, 2001B&B MoldersWater supply coupling with one-way valve for recreational vehicles
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US7954506 *Apr 21, 2003Jun 7, 2011John David SwanAutomatic freeze protection system for domestic plumbing systems
Classifications
U.S. Classification137/335, 122/448.1, 126/19.5, 137/899, 219/202, 296/168
International ClassificationF24D17/00
Cooperative ClassificationF24D17/00
European ClassificationF24D17/00