US1795602A - Carburetor - Google Patents

Description

CARBURETOR Filed April 23,

R. HAMILTON ET AL March 10, 1931.

El Robe/"Z Hamil/0 Herman 1 6/"00/1 E Patented Mar. 10, 1931 UNITED STATES PATENT OFFICE ROBERT HAMILTON AND HERMAN V. CROON, OF CHICAGO, ILLINOIS CARBURETOR Application filed April 23, 1927. Serial No. 185,999.

Our invention relates to carburetors of the to control the resistance in the Venturi noztype employed on motor vehicles and more zle; and particularly to mechanism controlled by the FE gure 4 is a vertical sectional view through choke valve for heating the fuel sprayed into modified form of nozzle built in accordance 5 the main air passage. with the features of our invention. 55

In order to augment the vaporization of the As shown on the drawings fuel sprayed into the main air passage of the The carburetor shown in Figure 1 is subcarburetor, we find it desirable, especially stantially like the conventional type of carin cold weather when the vehicle is being buretor, with the exception that the Venturi started, to preheat this passage. In order nozzle shown therein is provided with preto accomplish this desirable end we have (ieheating means to be described more in detail vised a switch construction controlled by hereinafter. The carburetor comprises a the choke valve of the carburetor and adaptbody 10 including an inlet air passage 11 and ed to automatically close an electric circuit a float chamber 12. Connected to the float 15 arranged to preheat the main air passage, chamber 12 is a fuel supply or gasoline line 65 when the choke valve is in its closed position. 13 win ch is suitably connected to the tank This construction is such that when the choke (not shown) of the vehicle. The fuel line 13 valve is open, the switch is open and when has a lateral tubular extension 14 threaded the choke valve is closed, the switch is autointo the body defining the float chamber 12. matically closed. A needle valve 16 extends into the tubular Our novel preheating mechanism is espemember i l and is adapted to control the sup cially useful in the starting of the motor and ply of fuel delivered to the float chamber in by its use we find that the engine may be set a well known manner. The upper end of into normal operation in much less time than valve member 16 is carried by a pair of pivheretofore. otally mounted lever members 17 which In accordance with the features of the premembers have enlarged ends 18 resting on ferred form of our invention, we provide the op of the float- 19. The rod 16 extends upmain air passage of the carburetor with a wardly through an opening 20 in float 19. It Venturi nozzle equipped with an electrical will be evldent from this illustration that the resistance for preheating the passage. The rise and fall of float 19 controls th a t 30 resistance comprises part of an electrical of fuel discharged into the chamber 12 from circuit controlled by a switch disposed on the the Source of supply. 4 exterior of the carburetor; the switch being Posltlpned Wlthln the y 10 is 11 right connected directly to the pivot of the choke angle P 1 tube member the "el'tlcal Valve leg 23 of which extends upwardly toward 85 1 A c Other ob ects and advantages of our in- 2 3 2322 5 3; g g figggi g gqffg uleitilbe vention will more fully appear from the foli U t1 f i lowin detailed description taken in connec- Ema openmb O (mg 1 W 110 mm mm g the rwcomym drawindwhich the float chamber 1s delivered to the tube. D b This opening 25 is controlled by a convenillustrates several embodiments thereof and m 27inch: the body 10 in a well known manner.

l igure 1 1s vertical sectional view taken The major part of the tube 22 is disposed g 5/ Carburetor @nbodylng the matures in the junction between the inlet air passage of P P lnvelltloni 11 and the main air passage 28 in which is t-l 2 1S a Sectional VleW taken 011 S disposed the Venturi nozzle 15. This juncstalliiially the line ITHII of Figure l, lOOlilIlg tion is designated by the reference character downwardly; 30. Also it will be noted from Figure 1 that Figure 3 is an enlarged detail sectional the upper end of the leg 23 of tube 22 extends 50 View of our novel switch construction used a slight ways into the Venturi nozzle 15.

tional needle valve member 26 threaded into The inlet air passage 11 is controlled by a choke valve 31 formed inte ral with a pivot member 32 journalled at its ends in diametrically opposed boses 33 formed integral with the body 10. One end of pivot member 32 is connected to a lever 34 used to operate the choke valve. The other end of the member 32 is connected. to a switch construction which will be described more in detail as the present description progresses.

The Venturi nozzle is preferably made of a material such as a metal having the inherent quality of offering a relatively high resistance to the flow of an electrical current. Also the Venturi nozzle 15 comprises conductor which is insulated from the por tion of the body 1O defining the passageway 23 by a sleeve of insulation 36. The upper end of nozzle 15 is grounded thru the body 10 by means of a small screw 37 threaded through the wall of tube 28, the sleeve 36 and into nozzle 15.

The upper end of passageway 28 is provided with an annular flange 38 by means of which the carburetor may be secured to the intake manifold (not shown) of the engine. Furthermore, disposed in the upper end of the passa eway 28 is a throttle valve 39 having formed integral therewith a pivotally mounted rod 40 which may be operated in any usual manner.

The lower end of nozzle 15 is held in place by means of a stud or screw 41 extending through the wall of passage 28, the sleeve 36 and threaded into nozzle 15. This stud 41 is insulated from the body 10 by means of a small bushing 42. The two studs 37 and 41 cooperate to connect an electrical circuit to the conductor or nozzle 15 and also function to anchor the nozzle to the body 10. \Ve shall now proceed to describe in detail the switch construction 35.

Suitably fastened to one end of the choke valve pivot member 32 is an upwardly extending arm 45 made of any suitable insulation. The upper end of this arm 45 fits in a socket 46 formed integral with one end of an angular switch member 47. The upper end of arm 45 is secured in the socket 46 by means of a small bolt 48. Also it will be noted that the bolt 48 is used to fasten one end of the electrical conductor 59 to the member 47. The other end of this conductor 49 may be con nected directly to the battery (not shown) of the vehicle.

The le 51 of member 47 is provided with a cylindrical bore 52 in which is disposed a compression spring 53. Also disposed in the bore 52 is a plunger 54. having a. slot 55. A pin 56 extends through slot 55 and is anchored at its ends in the leg 51 of member 47. The function of pin 56 is to limit the movement of the plunger 54 under the urging effect of the spring 53. The external end of the plunger 54 is provided with an enlarged head 58 adapted to abut the head of stud 41 as shown in Figure 3. Obviously when the head 58 is in contact with the head of stud 41', the electrical conductor 49 will be connected to the nozzle 15 and the current delivered to the nozzle 15 will travel circumferentially about it to the 'stud 37 which is grounded.

The operation of our mechanism is believed to be evident from the above detail description. lVhen the cold engine is being initially started, it is customary to close off the supply of air to the carburetor by shutting the choke valve 31. By the closing of valve 31 the member 47 is moved toward the passageway 28 to bring the plunger 54 into electrical contact with the stud 41. The head of stud 41 and the head 58 of plunger 54 in reality constitute a pair of electrical contacts. Due to the resilient mounting provided for plunger 54, it will be resiliently urged into contact with the head of stud 41, thus insuring a good electrical connection.

Now when this electrical connection is established, the nozzle 15 will function as a conductor in the circuit of the vehicle. Moreover, since the nozzle 15 is made of a material having a relatively high resistance to the flow of an electrical current therethrough, it Will become heated by the current flowing from stud 41 to stud 37, Which latter stud is grounded. The heated nozzle 15 will inturn preheat the fuel sprayed into the nozzle from the vertical leg 23 of tube 22. This preheating of the fuel will augment the vaporizing of the fuel and will facilitate the starting of the engine. 7

As soon as the engine is warmed up, the choke valve 31 is moved to its open position and the conductor 49 is automatically disconnected from the nozzle 15.

In Figure 4 we have illustrated a modified form of Venturi nozzle 15 comprising a cylinder of refractory material 16 having embedded in its inner surface a spiral resistance wire 61 connected to studs 41 and 37; the stud 41 being connectable to the switch mechanism of our invention and the stud 37 being adapted to be grounded. The wire 61 is made of a material having a high resistance. The operation of this type of nozzle is substantially like the nozzle 15 and it is therefore thought that no further description of it is needed.

3 It will be apparent that our novel Venturi nozzle may be introduced into the main passageway of any conventional type of carburetor with facility, by merely disconnecting the main passageway from the manifold and by removing the throttle valve 39f This construction not only enables us to apply our invention to carburetors already in use in automobiles, but enables us to readily replace the nozzle should it become damaged in use.

Now we desire it understood that although lbs we have illustrated and described in detail the preferred forms of our invention, the invention is not to be thus limited, but only in so far as defined by the scope and spirit of 5 the appended claims.

We claim:

1. In carburetion apparatus a mixing chamber for air and fuel, a nozzle disposed in said chamber, means for spraying a jet of fuel into said nozzle, an air passageway connected to said chamber and nozzle, a choke valve disposed in said passageway, an insulated electrical contact member connected to said choke valve and movable therewith,

an electrical conductor connected to said contact member, a resiliently mounted contact carried by said contact member, an external fixed contact connected to said nozzle cooperable with said resilient contact, said conductor comprising a part of a grounded electrical circuit, a grounded connection secured to said nozzle and means for operating said choke valve to move said resilient contact into and out of cooperation with said fixed contact.

2. In carburetion apparatus, a mixing chamber, a nozzle in said chamber, means for spraying a jet of fuel into said nozzle, an air passageway connected to said chamber and nozzle, a choke valve in said passageway 40 for controlling the flow of air therethrough, a contact member connected to and insulated from said choke valve, an electrical circuit connected to said member, a resilient contact carried by said member and an external fixed contact connected to said nozzle and cooperable with said resilient contact, said contact member being movable into and out of cooperation with said fixed contact by movement of said choke valve.

3. In carburetion apparatus, a mixing chamber, a nozzle in said chamber, means for spraying a jet of fuel into said nozzle, an air passageway connected to said chamber and nozzle, a choke valve in said passageway for controlling the flow of air therethrough, a contact member connected to and insulated from said choke valve, an electrical circuit connected to said member, a resilient contact carried by said member and an external fixed Contact connected to said nozzle and cooperable with said resilient contact, said contact member being movable into and out of cooperation with said fixed contact by move ment of said choke Valve, said nozzle comprising a conductor of relatively high resistance connected at one end to said fixed contact and having its other end grounded.

In testimony whereof, we have hereunto subscribed our names.

ROBERT HAMILTON.

HERMAN V. CROON.

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