US 2658734 A
Description (OCR text may contain errors)
0. HENNING CARBURETOR DE-ICING MEANS Filed Aug. 26, 1949 ATTORNEY .6 mm NN mN y 0 T T O FIG.3.
Nov. 10, 1953 Patented Nov. 10, 1953 CARBURETOR DE-ICING MEANS Otto Henning, St. Louis, Mo., assignor to Carter Carburetor Corporation, St. Louis, Mo., a cor poration of Delaware Application August 26, 1949, Serial No. 112,432
3 Claims. (01. 261-41) This invention relates to carburetors for internal combustion engines, and consists particularly in novel means for avoiding the ill effects of icing particularly in the vicinity of the throttle and idle port.
In the operation of a carburetor of the type having a butterfly throttle valve and an idling port controlled by the edge of the valve when the latter is closed or substantially closed, it is found in practice that the carburetor is subjected at times, to an icing condition on the throttle valve and in the region of the idling port. Rapid expansion of the air and vaporized fuel passing around the valve cools the valve and adjacent metal parts so as to condense and sometimes freeze moisture in the entering air. Such ice formation tends to cut off the supply of fuel and air to the engine resulting in erratic engine firing, or engine stalling.
It is the general object of the present invention therefore, to provide means automatically responsive to icing conditions to eliminate the ill effects mentioned and, more specifically to break up the ice formation and free the port. In the present example, such means preferably comprises a thermally responsive element mounted on the throttle valve adjacent the idle port sothatwhen the throttle valve is substantially closed, and ice has formed at the idle port, the
reduced temperature will cause a movement of the element and consequent breaking and removal of the ice.
The foregoing objects and other more specific objects will appear readily from the following description of the presently preferred embodiment of the invention, as illustrated in the accompanying drawing wherein:
Fig. l is a transverse sectional view vertically through a carburetor embodying the present invention;
Fig. 2 is an enlarged view in perspective, of the throttle valve having the device of the present invention associated therewith;
Fig. 3 is a view similar to that of Fig. 2, but showing the thermally responsive element with its free end displaced, and
Fig. 4 is a fragmentary enlarged view of the carburetor of Fig. 1, taken in the immediate region of the idle port and throttle valve thereof,
(not shown), passage Ill being controlled by a throttle valve IE on pivot shaft 16 journalled in the walls of mixture conduit'lll. Venturi stack l9, including main fuel nozzle 2!) is formed in the mixture conduit anterior to throttle valve l5. An air intake passage 23 is formed in the carburetor anterior to the Venturi stack. A floatcontrolled fuel chamber 24 is provided for supplying fuel to main nozzle passage 20, 28 through metering orifice 26, controlled by metering valve 21, and to idling ports 30 and 3| through passages 32 and 33. As indicated, idling port 3| is provided with an adjusting needle valve 34.
As is usual in carburetors of this type, port 30 opens to mixture conduit [0 in a position for control by the throttle valve I5 when the latter is closed, the edge 36 of throttle valve I5 then being adjacent the portion of the mixture conduit wall surrounding port 30. A bi-metallic strip element 31 is arranged substantially along a diameter of the anterior face 38 of throttle valve l5, and has its end 40 secured to the valve in any suitable manner, as by the rivets 4i The opposite free end 42 extends abreast of the throttle valve edge portion 36. Element 31 is so callbrated that in normal carburetor operation when the temperature adjacent the idle port and throttle valve is above freezing, the element will lie fiat on the valve as shown in the view of Fig. 2. On the other hand, when the element is subjected to freezing temperatures its free end portion 42 will move away from valve margin 36, as shown in Figs. 3 and 4, thereby breaking any ice formation adjacent the idle port and removing the ice particles.
Element 31 carried by the throttle valve in the position described, does not interfere in any way with normal carburetor operation in respect to fuel mixture flow through passage l0, since its normal or inactive position is flat against the anterior face of the throttle valve (Fig. 2). When however, the throttle is closed, the element is thereby located with its free end 42 closely opposed to port 30, so that in the presence of icing at the port it will function automatically in the manner indicated, to free the port. Element 31, which is capable of counteracting ice formation, may be mounted on structure adjacent the throttle or port.
Having now described and illustrated a presently preferred embodiment of the invention, it is to be understood that the embodiment shown may be modified without departing from the spirit and full intended scope of the invention as defined by the appended claims.
1. In a carburetor having a fuel mixture passage, a throttle valve therein, a fuel port in the wall of said passage adjacent the edge of said throttle valve when closed, and a thermostatic strip lying diametrically on said throttle valve and having one end fixed thereto, the opposite end of saidrthermostat being free and located immediately; adjacent the: marginal portion of said.
throttle valve, at temperatures above freezing, and
being constructed to flex away from said portion= thermostatic strip on the anterio'r'surface of said' throttle valve and fixed at one end thereto,.the free end of said strip terminating near and engaginggthemargin. of saidvalve adjacent said pprtt at temperatures above. freezing, saidv strip;
4. being constructed to flex away from said valve, in response to freezing ambient conditions, so as to break ice formation thereon.
3. In a carburetor having a fuel mixture passage and a. fuel port open to said passage, a butterfly throttle valve in control of said passage and port, and a thermostatic element having a free partlocated immediately adjacent thelperiphery Rcferelice slGitedifi the file of this patent UNITEDXSTATES PATENTS Number Name Date 2,05%),68'7 Gagg Nov. 3, 1936 20 21102211' Farrell Mar. 8, 1938 2,393,760 Eberhardt- Jan. 29, 1946 244025208 Read"- June:18; ..1'946