GB2533012A

GB2533012A - Structure of engine throttle assembly

Info

Publication number: GB2533012A
Application number: GB1511165.1A
Authority: GB
Inventors: Kuo Wei-Hsin; Huang Pi-Sung
Original assignee: Kwang Yang Motor Co Ltd
Current assignee: Kwang Yang Motor Co Ltd
Priority date: 2014-08-26
Filing date: 2015-06-25
Publication date: 2016-06-08
Anticipated expiration: 2035-06-25
Also published as: TW201608121A; DE102015110379A1; DE102015110379B4; GB201511165D0; GB2533012B; TWI616587B

Abstract

An engine throttle assembly includes a valve body 4, a throttle valve 5 arranged in an air passage 41 through the valve body 4, and a sensor box 6, comprising eg a pressure sensor 61 and a temperature sensor (63), arranged at one side of the valve body 4. An installation section 64 of a sensor box is mounted on a mounting section 44 of the valve body 4. The mounting section 44 of the valve body and the installation section 64 of the sensor box 6 form therebetween a multiple-bend circuitous pressure detection channel 441, 442, 642, 643 connected to and in communication with the air passage 41 to prevent waste gas and fuel vapour being driven by backfire into the throttle assembly and causing contamination or damage of the pressure sensor of the sensor box 6.

Description

TITLE: STRUCTURE OF ENGINE THROTTLE ASSEMBLY

(a) Technical Field of the Invention

The present invention relates generally to a structure of an engine throttle assembly, and more pat icularly to a structure of an engine throttle assembly that helps eliminate the drawback that a sensor box of a throttle assembly is directly impinged and thus damaged by an engine backfire so as to improve the pedomaance of the throttle assembly.

(b) Description of the Prior Art

As shown in FIG. 1, a throttle assembly 1 for use with an injection engine 10 comprises at least a valve body 11, a throttle valve 12 arranged in the valve body 11, and a temperature/pressure sensor 13 inserted into the valve body 11. The valve body 11 comprises an air passage Ill through which air may flow. The throttle valve 12 is arranged in the air passage 111. The throttle valve 12 comprises a valve rod 121 and the valve rod 121 extends outside the 15 valve body 11. The valve body 11 comprises an insertion hole 112 formed in a wall of the air passage Ii! at a gas outlet end thereof The insertion hole 112 is in communication with the air passage ill. The temperature/pressure sensor 13 is inserted into the insertion hole 112 so that the temperature/pressure sensor 13 may detect air pressure and temperature at the 20 gas outlet end of the air passage 111 and transmits messages of the detected air pressure and temperature to an electronic control unit (ECU) (not shown) to serve as references for controlling automobile traveling.

As shown in FIG. 1, the temperature/pressure sensor 13 is inserted into the insertion hole 112 of the valve body 11 and the insertion hole 112 is directly connected to the air passage 111. However, it is well known that during the operation of the engine, when a piston is driven upward from the bottom dead center, an intake valve and an exhaust valve that allows for ingress and egress of air would be both kept in an open condition in a short period of time so that a fraction of waste gas generated after combustion would be mixed with a fraction of fuel vapor and driven through the intake valve into the throttle assembly 1. This is often referred to as a "backfire". The waste gas and a fraction of fuel vapor that are driven by the backfire into the throttle assembly 1 would contact, through the insertion hole 112, the temperature/pressure sensor 13. To be clearer, since the insertion hole 112 is directly connected to the air passage 111, the temperature/pressure sensor 13 will be contaminated by the waste gas and the fraction of fuel vapor that are driven by the backfire into the throttle assembly 1 and may lose the functionality of detection. In an even worse situation, the waste gas containing carbon particles that have not completely combusted so that the carbon particles may be deposited and make the temperature/pressure sensor 13 losing the functionality of detection. Further, when a backfire situation occurs, the temperature/pressure sensor 13 may detect an instantaneous high pressure and a message of such a high pressure may be tiansmitted to the ECU, causing an incorrect determination made by the ECU and in the worst situations, driving safety may be jeopardized. Thus, as described above, the insertion hole 112 that is provided for installation of the temperature/pressure sensor 13 is in direct connection with the air passage 111 and this may readily make the temperature/pressure sensor 13 damaged and failing to operate properly due to an engine backfire. In other words, the temperature/pressure sensor 13 is arranged at the gas outlet end, so that the detected temperature is affected by the backfire so as to render incorrect readings of the temperature. Thus, further improvements are necessary.

As shown in FIG. 2, some manufacturers proposed an ECU 2, in which a temperature/pressure sensor (not shown) is housed. The ECU 2 comprises a detection holed-post 21 projecting therefrom. The detection holed-post 21 is insertable into the insertion bole I 12 of the valve body I 1. However, when an engine backfire event occurs, the waste gas and the fraction of fuel vapor that are driven by the backfire into the throttle assembly 1 may still move through the insertion hole 112 and then through the detection holed post 21 to get into the ECU 2 so as to similarly cause damage to the temperature/pressure sensor arranged inside the ECU 2. Thus, the solution of having the temperature/pressure sensor housed in the ECU 2 cannot resolve the drawback that the temperature/pressure sensor may be damaged by an engine backfire.

As shown in FIG. 3, to overcome the problem that the temperature/pressure sensor 13 may be damaged by the engine backfire, some manufacturers proposed to make, through drilling, a temperature/pressure introduction section 14 in the valve body 11 of the throttle assembly 1 to communicate with the air passage 111. The temperature/pressure introduction section 14 is composed of a first channel 141 and a second channel 142. The first channel 141 is connected to and in communication with the air passage 111 of the valve body 11 and the second channel 142 has an end connected to and in communication with the first channel 141 and an opposite end connected to and in communication with the temperature/pressure sensor 13, wherein the end of the second channel 142 that is connected to the first channel 141 receives a blocking bead 143 arranged therein and an end of the first channel 14 I that is connected to the second channel 142 also receives a blocking bead 144 arranged therein. The first channel 141 and the second channel 142 collectively form a detection channel in a bent arrangement so as to prevent the engine backfire from directly impinging the temperature/pressure sensor 13. However, the machining cost for making a detection channel in a bent arrangement with the first channel 141 and the second channel 142 may cause an excessively high cost of the throttle assembly 1. ln addition, the detection channel in a bent arrangement made up with the first channel 141 and the second channel 142 does not exhibit an excellent result of preventing the engine backfire from directly impinging the temperature/pressure sensor 13 and cannot overcome the issue that the temperature/pressure sensor 13 detects an instantaneous high pressure and transmits a high pressure message to the ECU to cause incorrect determination of the ECU. Further, the blocking bead 143 received in the end of the second channel 142 and the blocking bead 144 received in the first channel 141 would cause issues regarding machining preciseness and leakage. Thus, it is a challenge of the vehicle industry to provide a structure of a throttle assembly that helps prevent an engine backfire from directly impinging a temperature/pressure sensor.

SUMMARY OF THE INVENTION

The primary object of the present invention is to provide a structure of an engine throttle assembly, which overcomes the drawback of the conventional throttle assembly that a temperature/pressure sensor thereof is readily 5 impinged and thus damaged by an engine backfire.

The primary technical solution adopted in the present invention to achieve the above object is a structure of an engine throttle assembly. The throttle assembly comprises a valve body, a throttle valve arranged in the valve body, and a sensor box arranged at one side of the valve body. The valve body comprises an air passage that extends through the valve body.

The throttle valve is disposed in the air passage. The valve body comprises a mounting section and the mounting section receives the sensor box to be mounted thereto. The sensor box comprises an in section. The installation section corresponds to the mounting section of the valve body.

The mounting section of the valve body and the installation section of the sensor box define therebetween a pressure detection channel that is in a circuitous form and is connected to and in communication with the air passage.

An efficacy that can be achieved with the above technical solution of the 20 present invention is that with the arrangement that a sensor box comprises at least a sensor that is capable of detecting pressure (such as a pressure sensor or a pressure/temperature sensor) arranged therein and a first recessed section and a second recessed section of an installation section of the sensor box and a pressure introduction section and a first cavity of a valve body collectively defme a circuitous pressure detection channel and a separation rib of the installation section of the sensor box and a barrier wall of the mounting section of the valve body are deviated from each other to form a narrow passageway, waste gas and a fraction of fuel vapor that are driven by a backfire into a throttle assembly are effectively prevented from directly impinging the pressure sensor of the sensor box so as to prevent the waste gas and the fraction of fuel vapor that are driven by the backfire into the throttle assembly and carbon deposition from causing contamination or damage of the pressure sensor of the sensor box thereby increasing the lifespan and performance of the sensor box.

Another efficacy that can be achieved with the above technical solution of the present invention is that with the pressure introduction section and the first cavity of the valve body and the first recessed section and the second recessed section of the installation section of the sensor box that collectively define a circuitous pressure detection channel are respectively formed with the valve body the sensor box an integrated manner, the manufacturing process

S

and cost for individually processing the throttle assembly and the sensor box can be reduced thereby effectively lowering down the cost of the throttle assembly. Further, the design of the second cavity is made such that the waste gas and the fiaction of the fttel vapor and carbon particles that are driven into the pressure introduction section can be divided into separate flows so as to further improve the performance of the sensor box.

The foregoing objectives and summary provide only a brief introduction to the present invention. To fully appreciate these and other objects of the present invention as well as the invention itself, all of Which will become apparent to those skilled in the art, the following detailed description of the invention and the claims should be read in conjunction with the accompanying drawings. Throughout the specification and drawings identical reference numerals refer to identical or similar parts.

Many other advantages and features of the present invention will become manifest to those versed in the art upon making reference to the detailed description and the accompanying sheets of drawings in which a preferred structural embodiment incorporating the principles of the present invention is shown by way of illustrative example.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view showing a conventional throttle valve.

FIG. 2 is a schematic view showing another conventional throttle valve. FIG. 3 is a schematic view showing a further conventional throttle valve.

FIG. 4 is a cross-sectional view showing a throttle assembly according to the present invention FIG. 5 is a perspective view showing a valve body of the throttle assembly according to the present invention.

FIG. 6 is a schematic view showing a sensor box of the throttle assembly 10 according to the present invention.

FIG. 7 is a cross-sectional view of the throttle assembly according to the present invention taken from a different angle.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The following descriptions are exemplary embodiments only, and are not intended to limit the scope, applicability or configuration of the invention in any way. Rather, the following description provides a convenient illustration for implementing exemplary embodiments of the invention. Various changes to the described embodiments may be made in the function and arrangement of the elements described without departing from the scope of the invention as set forth in the appended claims.

Referring first to FIGS. 4, 5,6, and 7, the present invention provides a structure of an engine throttle assembly. The throttle assembly 3 comprises a valve body 4, a throttle valve 5 arranged in the valve body 4, and a sensor box 6 arranged at one side of the valve body 4.

As shown in FIGS. 4, 5, and?, the valve body 4 comprises an air passage 41 that extends through the valve body 4 and the throttle valve 5 is disposed in the air passage 41 so that the throttle valve 5 divides the air passage 41 into an inlet side 411 and an outlet side 412. The inlet side 411 is connectable to an air filter (not shown) and the outlet side 412 is connectable to an intake port (not shown) of the engine. An idling bypass valve 42 is mounted to a top of the valve body 4 at one side thereof and is located beside the outlet side 412.

A throttle control mechanism 43 is arranged on the same side as and below the idling bypass valve 42. The valve body 4 comprises a mounting section 44 formed on the side opposite to the throttle control mechanism 43 The mounting section 44 receives the sensor box 6 to be mounted thereto. The mounting section 44 comprises a pressure introduction section 441 formed therein at the outlet side 412 to extend to and communicate with the air passage 41 and also comprises a first cavity 442 formed therein at one side of the pressure introduction section 441 that is distant from the air passage 41 and a second cavity 443 fonned therein at the opposite side of the pressure introduction section 441. A barrier wall 4411 is formed between the first cavity 442 and the pressure introduction section 441 and the pressure introduction section 441 does not communicate with the first cavity 442 and the second cavity 443, namely the pressure introduction section 441 is separated from the first cavity 442 and the second cavity 443 by the barrier wall 4411. hi a view taken along a direction of air flowing, the mounting section 44 comprises an axle hole 444 extending through opposite sides of the valve body 4 in a radial direction at a location within a range defined by the longest (farthest) connection line between the outside diameters of the pressure introduction section 441 and the first cavity 442 toward the side corresponding to the inlet side 411. The mounting section 44 comprises, in 20 the inlet side 411, a temperature detection channel 445 extending to and communicating with the air passage 41. The mounting section 44 is extended outward to form three fastening holes 446.

As shown in FIGS. 4 and 7, the throttle valve 5 is arranged in the air passage 41 of the valve body 4. The throttle valve 5 is mounted to the valve axle 51. The valve axle 51 has two ends extending transversely through the valve body 4 along the axle hole 444 to each project outside the valve body 4. One of the ends of the valve axle 51 is coupled to a throttle control mechanism 43 of the valve body 4 and the other one is rotatably supported in (extending through) the axle hole 444 of the mounting section 44 of the valve body 4 to couple to the sensor box 6. As such, the throttle control mechanism 43 of the valve body 4 is operable to control the opening degree of the throttle valve 5.

As shown in FIGS. 4, 5, 6, and 7, the sensor box 6 comprises a pressure sensor 61, a position sensor 62, and a temperature sensor 63. The sensor box 6 comprises an installation section 64. The installation section 64 corresponds to the mounting section 44 of the valve body 4. The installation section 64 is extended to form three fixing holes 64! respectively corresponding to the thee fastening holes 446 of the mounting section 44 of the valve body 4. As such, the sensor box 6 can be fixed to the mounting section 44 of the valve body 4. The installation section 64 is partly recessed to form a first recessed section 642 and a second recessed section 643 conesponcling to the pressure introduction section 441, the first cavity 442, and the second cavity 443 of the mounting section 44 of the valve body 4. A separation element 644 is fonned between the first recessed section 642 and the second recessed section 643. The separation element 644 is made up of a separation rib. The second recessed section 643 comprises a pressure detection hole 645 formed therein. The pressure sensor 61 of the sensor box 6 is coupled to the pressure detection hole 645; the position sensor 62 of the sensor box 6 is coupled to the valve axle 51 of the throttle valve 5 to detect an opening degree of the throttle valve 5; and the temperature sensor 63 of the sensor box 6 is coupled to the temperature detection channel 445 of the valve body 4 to detect the temperature of air entering the throttle assembly 3.

As shown in FIGS. 4 and 7, to embody the throttle assembly 3 of the present invention, when the sensor box 6 is mounted to the mounting section 44 of the valve body 4, the first recessed section 642 of the installation section 64 of the sensor box 6 covers the pressure introduction section 441, the second cavity 443, and a portion of the first cavity 442 of the valve body and the separation rib 644 of the installation section 64 of the sensor box 6 is deviated from the bather wall 4411 of the mounting section 44 of the valve body 4 so as to form a connection section A connecting between and in communication with the first cavity 442 and the first recessed section 642. The first recessed section 642 of the installation section 64 of the sensor box 6 individually define a first compartment B, or alternatively, a second cavity 443 is provided at the opposite side of the pressure introduction section 441 so that the first recessed section 642 in combination with the second cavity 443 of the valve body 4 provides an increased space for the first compartment B. The second recessed section 643 of the installation section 64 of the sensor box 6 and the first cavity 442 of the valve body 4 collectively define a second compartment C. To be more specific, the pressure introduction section 441, the first cavity 442 of the valve body 4 and the first recessed section 642 and the second recessed section 643 of the installation section 64 of the sensor box 6 collectively form a multiple-bend circuitous pressure detection channel between the mounting section 44 of the valve body 4 and the installation section 64 of the sensor box 6 and in communication with the air passage 41. In the example embodiment, an arrangement of four bends is taken as an example for illustration, but the present invention is not limited to such an arrangement.

As shown in FIGS. 4 and 7, when air moves, through the inlet side 411 of the throttle assembly 3, into the air passage 41 of the valve body 4, the temperature sensor 63 of the sensor box 6 detects the temperature of the air through the temperature detection channel 445 in communication with the valve body 4 and supplies a message of the air temperature to an engine control unit (ECU) (not shown) to serve as a reference for controlling the operation of the engine. The pressure sensor 61 of the sensor box 6 detects, through the circuitous pressure detection channel formed by the pressure introduction section 441 and the first cavity 442 of the valve body 4 mid the first recessed section 642 and the second recessed section 643 of the installation section 64 of the sensor box 6, as well as the pressure detection hole 645 of the sensor box 6, the pressure of the air and supplies a message of the air pressure to the ECU to serve as a reference for controlling the operation of the engine. When the throttle valve 5 of the throttle assembly 3 is rotated, the position sensor 62 of the sensor box 6 detects the opening degree of the throttle valve 5 and supplies a message of the opening degree of the throttle valve 5 to the ECU to serve as a reference for controlling the operation of the engine.

As shown in FIGS. 4 mid 7, when a back-fire event occur during the operation of the engine, waste gas and a fraction of fuel vapor driven by the backfire into the throttle assembly 3 will enter the pressure introduction section 441 of the valve body 4. Since the pressure introduction section 441 and the first cavity 442 of die valve body 4 and the first recessed section 642 and the second recessed section 643 of the installation section 64 of the sensor box 6 collectively form a circuitous pressure detection channel and since the separation rib (the separation element) 644 of the installation section 64 of the sensor box 6 and the barrier wall 4411 of the mounting section 44 of the valve body 4 are deviated from each other to form the connection section A connecting between mid in communication with the first cavity 442 and the first recessed section 642, the waste gas and the fraction of fuel vapor driven by the backfire into the throttle assembly 3 are effectively prevented from directly impinging the pressure sensor 61 of the sensor box 6. Also, the first compartment B defmed by the first recessed section 642 of the installation section 64 of the sensor box 6 and the second cavity 443 of the valve body 4 and the second compartment C defined by the second recessed section 643 of the installation section 64 of the sensor box 6 and the first cavity 442 of the valve body 4 are arranged such that the connection section A that is in communication with the first compartment B and the second compartment C is formed between the pressure introduction section 441 and the separation element 644, so that the first compartment B and the second compartment C may function as a pressure release space, whereby an instantaneous high pressure caused by a backfire can be released effectively and the pressure sensor 61 of the sensor box 6 is prevented from detecting such a high pressure of the backfire and transmitting an incorrect message of high pressure resulting from the backfire to the ECU to cause incorrect determination made by the ECU. It is noted that for the first compartment B defined by the first recessed section 642 of the installation section 64 of the sensor box 6 and the second cavity 443 of the valve body 4, the first compartment B may accommodate the waste gas and the fraction of fuel vapor that are driven by a backfire into the throttle assembly 3 and deposition of carbon so as to prevent the waste gas and the fraction of ftiel vapor that are driven by the backfire into the throttle assembly 3 and carbon deposition from causing contamination or damage of the pressure sensor 61 of the sensor box 6 thereby increasing the lifespan and performance of the sensor box 6.

The primary efficacy of the present invention is that with the arrangement that the sensor box 6 comprises at least a sensor that is capable of detecting pressure (such as a pressure sensor or a pressure/temperature sensor) arranged therein and the first recessed section 642 and the second recessed section 643 of the installation section 64 of the sensor box 6 and the pressure introduction section 441 and the first cavity 442 of the valve body 4 collectively define a circuitous pressure detection channel and the separation rib 644 of the installation section 64 of the sensor box 6 and the barrier wall 4411 of the mounting section 44 of the valve body 4 are deviated from each other to form the connection section A connecting between and in communication with the first cavity 442 and the first recessed section 642, waste gas and a fraction of fuel vapor that are driven by a backfire into the throttle assembly 3 are effectively prevented from directly impinging the pressure sensor 61 of the sensor box 6 so as to prevent the waste gas and the fraction of fuel vapor that are driven by the backfire into the throttle assembly 3 and carbon deposition from causing contamination or damage of the pressure sensor 61 of the sensor box 6 thereby increasing the lifespan and performance of the sensor box 6.

Another efficacy of the present invention is that the throttle assembly 3 is molded through casting so that the pressure introduction section 441 and the first cavity 442 and the second cavity 443 of the valve body 4 can be integrally fonned during the casting operation of the throttle assembly 3. Further, the sensor box 6 is made through injection molding so that the first recessed section 642 and the second recessed section 643 of the installation section 64 of the sensor box 6 can be integrally formed during the injection molding operation of the sensor box 6. As such, the manufacturing process and cost for individually processing the throttle assembly 3 and the sensor box 6 can be reduced thereby effectively lowering down the cost of the throttle assembly 3. Further, the design of the second cavity 443 is made such that the waste gas and the fraction of the fuel vapor and carbon particles that are driven into the pressure introduction section 441 can be divided into separate flows so as to further improve the petfotmance of the sensor box 6.

It will be understood that each of the elements described above, or two or more together may also find a useful application in other types of methods 5 differing from the type described above.

While certain novel features of this invention have been shown and described and are pointed out in the annexed claim, it is not intended to be limited to the details above, since it will be understood that various omissions, modifications, substitutions and changes in the forms and details of the device illustrated and in its operation can be made by those skilled in the art without departing in any way from the claims of the present invention.

Claims

I CLAIM: 1. A structure of an engine throttle assembly, the throttle assembly comprising a valve body, a throttle valve arranged in the valve body, and a sensor box arranged at one side of the valve body; the valve body comprising an air passage that extends through the valve body, the throttle valve being disposed in the air passage, the valve body comprising a mounting section, the mounting section receiving the sensor box to be mounted thereto, the sensor box comprising an installation section, the installation section corresponding to the mounting section of the valve body, characterized in that the mounting section of the valve body and the installation section of the sensor box define therebetween a pressure detection channel that is in a circuitous form and is connected to and in communication with the air passage.
2. The structure of the engine throttle assembly according to claim 1, wherein the mounting section of the valve body fitrther comprises a pressure introduction section famed therein to be connected to and in communication with the air passage and also comprises a first cavity formed therein at one side of the pressure introduction section that is distant from the air passage; the installation section of the sensor box is partly recessed to fo m a first recessed section and a second recessed section, a separation element being formed between the first recessed section and the second recessed section; the circuitous pressure detection channel is collectively formed of the pressure introduction section and the first cavity of the valve body and the first recessed section and the second recessed section of the installation section of the sensor box.
3. The structure of the engine throttle assembly according to claim 1, wherein the throttle valve is structured such that the air passage of the valve body is divided into an inlet side and an outlet side, the inlet side being connectable to an air filter, the outlet side being connectable to an intake port of an engine; an idling bypass valve is mounted to a top of the valve body at one side thereof and is located beside the outlet side, a throttle control mechanism being arranged on the same side as and below the idling bypass valve.
4. The structure of the engine throttle assembly according to claim 2, wherein the mounting section comprises a second cavity formed therein, the pressure introduction section having an outer circumference along which a bather wall is formed so that the pressure introduction section, the first cavity, the second cavity that are formed in the mounting section are separated from each other by the barrier wall; and, in a view taken along a direction of air flowing in the air passage, the mounting section comprises an axle hole extending to the air passage at a location with a range defined by the longest connection line between the outside diameters of the pressure introduction section and the first cavity and a temperature detection channel formed in the inlet side and extending to and in communication with the air passage.
5. The structure of the engine throttle assembly according to claim 1, wherein the throttle valve is mounted to a valve axle, the valve body comprising an axle hole extending transversely through the valve body along the axle hole to each project outside the valve body; and one of the ends of the valve axle is coupled to a throttle control mechanism outside the valve body and the other one extends through the axle hole of the valve body to couple to the sensor box.
6. The structure of the engine throttle assembly according to claim 2, wherein the sensor box comprises a pressure detection hole formed in the second recessed section.
7. The structure of the engine throttle assembly according to claim 2, wherein the separation element of the installation section of the sensor box comprises a separation rib and a bather wall is formed between the first cavity and the pressure introduction section of the mounting section of the valve body so that the mounting section and the installation section are mounted to each other, the separation rib and the bather wall are deviated from each other to form a connection section connecting between and in communication with the first cavity and the first recessed section.
8. The structure of the engine throttle assembly according to claim 2, wherein the first recessed section of the installation section of the sensor box is structured to form, at least alone, a first compartment; the second recessed section of the installation section of the sensor box and the first cavity of the valve body collectively form a second compu tment; a connection section is formed between the pressure introduction section and the separation element to connect between and communicate with the first compartment and the second comp& Tient; and a second cavity is formed in an opposite side of the pressure introduction section, the first compartment being collectively formed of the second cavity and the first recessed section to provide an increased space of the first compartment.
9. The structure of the engine throttle assembly according to claim 2, wherein the installation section of the sensor box is mounted to the mounting section of the valve body in such a way that the first recessed section of the installation section of the sensor box covers the pressure introduction section and a portion of the first cavity of the valve body; a channel that is connected between the first recessed section and the first cavity is formed between the pressure introduction section and the separation element; and a second cavity is formed on an opposite side of the pressure introduction section and the first recessed section of the installation section of the sensor box also covers the second cavity of the valve body.The structure of the engine throttle assembly according to claim 1 or 2, wherein the throttle valve is structured such that the air passage of the valve body is divided into an inlet side that receives a supply of air from the air filter and an outlet side that supplies air to the intake port of the engine; the sensor box comprises therein at least one sensor that has a function of detecting pressure, the sensor that detects the pressure being connected to the circuitous pressure detection channel; the circuitous pressure detection channel being connected to the outlet side of the valve body; the sensor box comprising a pressure detection hole, the sensor that detects the pressure being set in communication with the circuitous pressure detection channel through the pressure detection hole; the sensor box further comprises a position sensor arranged therein, the position sensor being indirectly coupled to the throttle valve; the mounting section of the valve body comprises an axle hole farmed therein, the axle hole receiving the valve axle of the throttle valve therein, the position sensor being indirectly coupled to the throttle valve through the valve axle; and the sensor box further comprises a temperature sensor arranged therein, the mounting section of the valve body comprising a temperature detection channel formed therein, the temperature sensor being connected to the temperature detection channel of the valve body; the temperature detection channel being connected to the inlet side of the valve body.