Throttle valve for an internal combustion engine provided with a conditioning circuit

Abstract

A throttle valve for an internal combustion engine provided with a valve body, a tubular feeding duct defined in the valve body, a throttle plate, and an actuating device which controls rotation of the throttle plate. The actuating device includes an electric motor and an actuating device conditioning circuit defined in the valve body. The conditioning circuit includes a tube made of a first material able to conduct heat, and the valve body is entirely made of a second metal material and is provided with a seat for housing the tube, in which is provided a layer of a structural and heat-conducting resin, interposed between the seat and the tube.

The invention claimed is: 
     
       1. A throttle valve for an internal combustion engine comprising:
 a valve body entirely made of a first metallic material and defined by at least a first and a second shell portion; 
 a tubular feeding duct defined in the valve body and through which the air taken in by the internal combustion engine flows; 
 a throttle plate arranged inside the feeding duct and splined to a shaft mounted in a rotary manner so as to rotate around a rotation axis between a maximum opening position and a closing position to open and close the feeding duct; 
 an actuating device for controlling rotation of the throttle plate around the rotation axis, the actuating device including an electric motor and a gear drive for transmitting motion from the electric motor to the shaft of the throttle plate; 
 an actuating device conditioning circuit defined in the valve body including a seat and a tube operatively supported in said seat for the passage of conditioning fluid, said tube in hydraulic communication with a pump that circulates the conditioning fluid and feeds it to the tube to condition the various parts of the throttle valve; said seat including an inner surface formed on at least one of said first and second shell portions, said inner surface terminating at an upper surface of said valve body; 
 wherein the tube is made of a second material different from said first metallic material and that is able to conduct heat, wherein said second material is selected from a group including: steel, aluminum, or copper; and 
 a substantially uniform layer of structural and heat-conducting resin interposed between the seat and the tube and applied on the entire available inner surface of the seat but wherein the upper surface of said valve body is free of said resin so as to allow fixing of the tube in said seat. 
 
     
     
       2. The valve as set forth in  claim 1 , wherein the tube is fixed in the seat by the layer of structural and heat-conducting resin. 
     
     
       3. The valve as set forth in  claim 1 , further including a lock for constraining the tube in the appropriate seat, the lock including a number of fixing brackets or plates distributed along the entire length of the tube. 
     
     
       4. The valve as set forth in  claim 1 , wherein the throttle plate is made of the same first metal material that makes up the valve body. 
     
     
       5. The valve as set forth in  claim 1 , wherein the seat is open on the upper side and the surface that defines the seat itself has a shape that is complementary to an outer surface of the tube. 
     
     
       6. The valve as set forth in  claim 1 , wherein the valve body includes a tubular housing arranged next to the feeding duct and housing the electric motor; and wherein the gear drive is arranged in a chamber of the valve body defined by first and second shells, the first shell defining a removable lid and the second shell arranged next to the feeding duct and next to the tubular housing. 
     
     
       7. The valve as set forth in  claim 6 , wherein the tube includes a first branch and a second branch extending in the tubular housing, and a curved connecting portion extending between the first and second branches. 
     
     
       8. The valve as set forth in  claim 7 , wherein the tube is substantially L-shaped.