JP2008008194A - Electric control throttle valve device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric control throttle valve device showing high heating effect around a throttle valve even if the same is comprised of a resin housing. <P>SOLUTION: The electric control throttle valve device A is provided with a disk shape valve element 4 fixed on an exposed section in a cylindrical hole of a shaft 3 rotatably arranged by passing through the cylindrical hole forming an intake air passage 2 of the housing, and opens and closes the intake air passage 2 by the valve element 4 by rotating the shaft 3 around a shaft thereof by an electric motor 5. A ring body 14 formed out of a material of high heat transfer rate is arranged in a wall surface of a housing 1 surrounding an annular inner wall surface of the intake air passage 2 facing an circumference edge of the valve element 4 under full closed condition. A storage hole 10 forming member 13 of the electric motor 5 is formed out of a material of high heat transmission, the ring body 14 and the motor storage hole forming member 13 are connected in such a manner that heat can be transferred, and temperature of the ring body 14 is adjusted by heat generated by the electric motor 5. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an electric throttle valve device that is provided in an intake passage of an internal combustion engine and can prevent icing.

  Conventionally, there has been proposed a throttle valve device that includes a resin housing and that does not freeze even when traveling in cold outside air (see Patent Document 1).

This is because the inner peripheral surface of the intake passage in which the valve body of the resin housing is disposed is formed of a metal ring, and engine cooling water as a heating fluid is provided in the passage provided in the wall portion of the housing so as to touch the metal ring. In this way, the metal ring is heated by the heat of the cooling water to prevent the valve body from being locked by icing.
JP-A-2-91431

  When the warmed-up engine is stopped in a cold region or the like, the water present in the intake passage may be cooled by the outside air and the throttle valve may be frozen and fixed. In this case, since the throttle valve is fixed at the next engine start and the intake air amount cannot be adjusted, there is a possibility that a desired intake air amount cannot be obtained.

  The technique of the said patent document 1 is trying to cancel | release freezing using engine cooling water. Here, since the temperature of the engine cooling water rises by using the heat of the engine, it takes time until the temperature of the engine cooling water reaches a temperature at which icing can be released after the engine is cold started. End up. For this reason, there is a possibility that icing of the throttle valve cannot be released at an early stage from the start of the engine, a desired intake air amount cannot be obtained, and a stable engine operation cannot be performed.

  In view of the above problems, an object of the present invention is to provide an electric throttle valve device that can quickly release icing from the start of the engine.

  The present invention comprises a disc-like valve element fixed to an exposed portion of a cylindrical hole of a shaft that is rotatably disposed through a cylindrical hole that constitutes an intake passage of a housing, and the shaft is driven by an electric motor. In the electrically controlled throttle valve device that controls the flow rate by opening and closing the intake passage by the valve body by rotating around the axis, the annular inner wall surface of the intake passage facing the peripheral edge of the fully closed valve body and / or the A ring body made of a material having a high thermal conductivity is disposed in the wall surface of the housing surrounding the annular inner wall surface, and the case of the electric motor and / or the housing hole forming member of the electric motor is made of a material having a high thermal conductivity. The ring body and the motor case and / or the motor housing hole forming member are connected so as to be able to conduct heat, and the freezing of the valve body is performed using heat generated by the electric motor. It was to be released.

  Therefore, in the present invention, a ring body made of a material having high thermal conductivity is disposed in the annular inner wall surface of the intake passage facing the periphery of the fully closed valve body and / or the wall surface of the housing surrounding the annular inner wall surface. In addition, the case of the electric motor and / or the accommodation hole forming member of the electric motor is formed of a material having high thermal conductivity, and the ring body and the motor case and / or the motor accommodation hole forming member are connected so as to be capable of conducting heat. The temperature of the ring body is adjusted by the heat generated by the electric motor. For this reason, the surface of the intake passage is heated and kept warm by the heat generated by the electric motor, so that the icing of the valve body can be released early even when the engine is cold started. Can provide stable operation at an early stage.

  Hereinafter, an embodiment of an electric throttle valve device according to the present invention will be described with reference to FIGS. 1 is a cross-sectional view of an electric throttle valve device according to a first embodiment to which the present invention is applied, FIG. 2 is a cross-sectional view taken along the line AA of FIG. 1, and FIG. 3 is an application state of the electric throttle valve to an engine. 4 is a system configuration diagram of the electric throttle valve device, FIG. 5 is a control flowchart of the electric throttle valve device, FIG. 6 is a cross-sectional view of the second embodiment of the electric throttle valve device, and FIG. It is sectional drawing of 3rd Example of an electrically controlled throttle valve apparatus.

  1 and 2, an electrically controlled throttle valve device A according to the present embodiment includes a throttle shaft 3 and a throttle disposed in a resin housing 1 so as to be rotatable across a cylindrical passage 2 constituting an intake passage. A butterfly valve body 4 that is fixed to the shaft 3 by a screw 3A to open and close the passage 2, an electric motor 5 that opens and closes the valve body 4, and a reduction gear that decelerates the rotation of the electric motor 5 and transmits it to the throttle shaft 3 6, a return spring mechanism 7 that is disposed between the reduction gear 6 and the housing 1 and biases the valve body 4 in the closing direction, and a throttle opening sensor 8 that detects the valve opening based on the rotation angle of the throttle shaft 3. With.

  The resin housing 1 includes a main body housing 11 that includes a passage 2 in which the throttle shaft 3 and the valve body 4 are disposed, and a motor housing hole 10 that houses the electric motor 5, and is attached to a side surface of the main body housing 11. An end portion of the throttle shaft 3 and an output shaft of the electric motor 5 are housed inside, a reduction gear mechanism 6 for transmitting the rotation of the output shaft to the throttle shaft 3, and a cover 12 for housing the throttle opening sensor 8; It is composed of

  The main body housing 11 has a housing hole constituting portion 13 constituting a wall surface of the motor housing hole 10 for housing the electric motor 5 and a wall surface forming a surface of the passage 2 in contact with or close to the peripheral edge of the fully closed valve body 4. An integrally formed insert member 16 comprising an annular portion (ring body) 14 formed in the above and a connecting portion 15 that integrally connects both the portions 13 and 14 is provided. The insert member 16 is in a state in which the portion 13 constituting the motor accommodation hole 10 is in direct contact with the electric motor 5 exposed and accommodated from the surface of the molded resin. It is not exposed on the surface of the intake passage 2 that houses the air, but is disposed inside the wall with a thin resin layer sandwiched from the surface formed of resin.

  The main body housing 11 is formed by integrally molding the insert member 16 by setting the insert member 16 in the cavity of the molding die in the same manner as the core and injecting and filling the resin into the cavity of the die. Can be molded. As a material having a high thermal conductivity used for the insert member 16, metals such as gold and silver, copper, a relatively inexpensive aluminum alloy, and the like can be used. The insert member 16 is generally made of a metal material having a high thermal conductivity. However, the insert member 16 is not limited to this, and even a non-metal material has a high thermal conductivity. Any material can be used.

  The throttle shaft 3 is rotatably arranged via a bearing 18 in a state where the intake passage 2 of the main body housing 11 is traversed, and a valve body 4 is integrated with a screw 3A at a portion exposed in the intake passage 2. It is fixed to. The illustrated state shows the valve element 4 in the fully closed state in which the intake passage 2 is closed. A throttle gear 20 of the reduction gear mechanism 6 is fixed to an end portion of the cover 3 of the shaft 3 and the valve body 4 is urged between the throttle gear 20 and the main body housing 11 in a fully closed state. A return spring 7 is disposed, and a throttle opening sensor 8 is disposed at the shaft end of the throttle shaft 3. The throttle opening sensor 8 detects the opening of the valve body 4 and outputs the detection signal to the ECU that controls the engine.

  The reduction gear mechanism 6 includes a fan-shaped throttle gear 20 fixed to the throttle shaft 3, a drive gear 21 fixed to the output shaft of the electric motor 5, and a large-diameter gear 23A rotatably supported by the intermediate shaft 22. And an intermediate gear 23 that meshes the throttle gear 20 with the small diameter gear 23B and meshes with the drive gear 21 of the output shaft of the electric motor 5 with the large diameter gear 23A.

  As shown in FIG. 3, the electric throttle valve device A having the above-described configuration is disposed between an intake collector IC that collects the inlets of all intake manifolds IM of the multi-cylinder engine E and an air cleaner (not shown). Then, as shown in FIG. 4, the throttle valve opening is controlled by controlling the control current of the electric motor 5 by the engine control ECU according to the depression amount of the accelerator pedal AP, and the obtained throttle valve opening is obtained. Is detected by the throttle opening sensor 8 and fed back to the ECU.

  In the electric throttle valve device A having this configuration, the electric motor 5 drives the throttle shaft 3 and the valve body 4 to open and close via the reduction gear mechanism 6 so as to respond to, for example, the degree of depression of the accelerator pedal AP. The opening degree is adjusted. At that time, the electric motor 5 is supplied with a drive current to exert a predetermined driving force for driving the valve body 4 while receiving the negative urging force of the return spring 7 of the valve body 4. Fever. This heat is transmitted to the accommodation hole forming portion 13 of the insert member 16 of the main body housing 11 that forms the accommodation hole 10 that accommodates the electric motor 5, and then via the connecting portion 15 of the insert member 16. It is transmitted to the annular portion 14 in the wall surface of the intake passage 2. And the surface of the channel | path 2 is heated and heat-retained through the thin resin layer from the annular part 14 in a wall surface.

  Further, the surface of the passage 2 in contact with or close to the periphery of the valve body 4 of the intake passage 2 is formed of a resin forming the housing 1. While the resin is light in weight but has poor heat conductivity, the surface formed of the resin has a smaller contact angle with water compared to a metal surface such as an aluminum alloy, and the water attached to the surface is a ball. It tends to become a shape. For this reason, even if water adheres to the resin surface, it has a property that it is easily removed.

  Therefore, by heating and keeping the surface of the intake passage 2 with the heat generated by the electric motor 5, the inner wall surface of the housing 1 around the valve element 4 can be used even if a resin having poor thermal conductivity is used as the material of the housing 1. Can be reliably kept above the freezing temperature. In addition, the attached water is kept at a small contact angle, so that it is prevented from being strongly attached to the surface of the passage 2 and can be easily detached.

  For this reason, it is possible to prevent moisture in the unburned gas returned from the engine crank chamber from adhering and freezing even if it flows through the throttle valve device A, and even if it adheres, it can be easily detached. it can. Further, even if there is icing before the engine is started, the icing can be quickly dissolved by overheating and heat insulation via the insert member 16 and can be easily detached due to the properties of the resin surface.

  FIG. 5 shows the control of the electric throttle valve device A that is executed at regular intervals by the engine control CPU when the outside air temperature is low or when the engine is warming up after engine startup. It is a flowchart. That is, when the outside air temperature is low or during the warm-up operation after starting the engine, if the unburned gas in the engine crank chamber is returned to the upstream and downstream of the electric throttle valve device A and burned again, the unburned gas There is a possibility that water contained in the gas freezes between the valve body 4 and the inner wall surface of the housing 1 and the valve body 4 does not operate. A control flowchart of the electric throttle valve device A will be described below.

  First, in step S1, an opening command value to the electric motor 5 and an opening detection value from the throttle opening sensor 8 are read. In step S2, a deviation between the opening command value and the detected opening value is obtained. The calculation is performed and the process proceeds to step S3.

  In step S3, it is determined whether or not the deviation calculated in step S2 exceeds a preset value. If the deviation exceeds the preset value, the process proceeds to step S4. In step S4, the motor temperature increasing operation is performed. And the flag (F) during temperature rise is set to “1”, and the current process is terminated.

  As the motor temperature increasing operation, for example, by continuing to drive the electric motor 5 so that the valve body 4 is closed, a large current is caused to flow so that the valve body 4 is brought into contact with a fully-closed stopper (not shown). By continuing to drive in the fully closed state, the heat generation of the electric motor 5 is promoted and its temperature is increased, or the opening command signal is slightly increased or decreased to cause an excessive current to flow through the electric motor 5. The heat generation of the motor 5 is promoted to increase its temperature. As a result, the sticking of the valve body 4 due to freezing is eliminated by the heat applied from the insert member 16 and the torque of the electric motor 5 applied to the valve body 4. Since the surface of the intake passage 2 is formed of resin, the above-described sticking elimination operation is further facilitated.

  If the deviation does not exceed the set value in step S3, the process proceeds to step S5. In step S5, it is determined whether or not the deviation exceeds the set allowable value smaller than the set value. If the deviation exceeds the allowable value, the process proceeds to step S6. If the deviation does not exceed the allowable value, the process proceeds to step S8. In step S6, it is determined whether or not the temperature rising flag is “1”. If the temperature rising flag is “F = 1”, the process proceeds to step S7, and the temperature rising flag is “F = If it is “0”, the process proceeds to step S8.

  In step S7, the motor temperature increasing operation is continued. In step S8, the motor temperature increasing operation is canceled, the temperature increasing flag is set to “F = 0”, and the current process is terminated.

  In the determination in step S5 and step S6, when the icing of the valve body 4 occurs and the motor temperature increase operation in step S4 is started, the deviation decreases below the allowable value set in step S5. It is for continuing until.

  That is, when the deviation exceeds the allowable value but does not exceed the set value, the deviation that once exceeded the set value is reduced to the set value or less by the motor temperature increasing operation by the determination in step S6. In (F = 1), the motor temperature increasing operation is continued until the deviation drops below the allowable value set in step S5. If the deviation does not exceed the set value but exceeds only the allowable value (F ≠ 1), the process proceeds from step S6 to step S8, the motor temperature increasing operation is not performed, and the temperature increasing flag is set to “ F = 0 ”, and the current process is terminated as it is. As described above, the start of the motor temperature rising operation is determined by the set value, and the stop is determined by the allowable value, so that control hunting can be prevented.

  In the second embodiment of the electric throttle valve device A shown in FIG. 6, the insert member 6 having a high heat tradition rate is exposed on the surface of the intake passage 2 around the throttle shaft 3. . The surface of the intake passage 2 around the shaft 3 and the edge of the valve body 4 are generally set with a narrow clearance to reduce the amount of air passing when fully closed. It is a part where sticking due to freezing is likely to occur. By exposing the insert member 16 in a region where the clearance is narrow, the icing portion is directly warmed by the insert member 16, thereby further eliminating the lock of the valve body 4 due to icing. Since the insert member 16 can be formed with high precision by die casting of aluminum alloy or the like, the clearance can be formed narrower, and both the anti-icing effect and the high-precision flow rate control by the valve body 4 can be achieved. Can be planned.

  In the third embodiment of the electric throttle valve device A shown in FIG. 7, the annular portion 14 disposed in the wall surface of the housing body 11 surrounding the intake passage 2 is omitted on the tip side of the portion through which the throttle shaft 3 passes. “C” shape. As described above, when the annular portion 14 is not provided on the entire circumference of the intake passage 2 and is provided only on a half circumference, the transmitted heat of the electric motor 5 is transmitted to a portion around the throttle shaft 3 where icing is relatively likely to occur. Therefore, it can be supplied in a concentrated manner, and the fixation due to freezing can be eliminated efficiently.

  In the embodiment described above, the housing 1 is a resin housing in which the insert member 16 is molded. However, although not shown, the same effect can be obtained even in a metal housing formed by die casting such as an aluminum alloy. Can be demonstrated.

  In the above-described embodiment, the ring body 14 has been described as not being exposed on the inner wall surface of the intake passage 2, but may be exposed on the inner wall surface of the intake passage 2, although not illustrated.

  In the present embodiment, the following effects can be achieved.

  (A) An electric motor including a disc-like sprung body 4 fixed to an exposed portion in a cylindrical hole of a shaft 3 that is rotatably disposed through a cylindrical hole constituting the intake passage 2 of the housing 1. 5, the shaft 3 is rotated around its axis, so that the valve body 4 opens and closes the intake passage 2 to control the flow rate, thereby facing the peripheral edge of the fully closed valve body 4. A ring body 14 formed of a material having high thermal conductivity is disposed in the annular inner wall surface of the intake passage 2 and / or the wall surface of the housing 1 surrounding the annular inner wall surface, and the case of the electric motor 5 itself and / or The housing hole 10 forming member 13 of the electric motor 5 is formed of a material having high thermal conductivity, and the ring body 14 and the motor case and / or the motor housing hole forming member 13 are connected so as to be able to conduct heat. 15) to and to adjust the temperature of the ring member 14 by heat generated by the electric motor 5. Therefore, by heating and keeping the surface of the intake passage 2 with the heat generated by the electric motor 5, the inner wall surface of the housing 1 around the valve body 4 can be reliably kept above the freezing temperature even when the engine is cold started. It can be kept warm, and deicing is quicker than when engine cooling water is used as a heat source.

  (A) Since the ring body 14 is embedded in the wall surface of the intake passage 2 made of resin, even if a resin with poor thermal conductivity is used as the material of the housing 1, the heat generated by the electric motor 5 is used. By heating and keeping the surface of the intake passage 2, the inner wall surface of the housing 1 around the valve body 4 can be reliably kept above the freezing temperature. In addition, the attached water is kept at a small contact angle, so that it is prevented from being strongly attached to the surface of the passage 2 and can be easily detached.

  (C) The ring body 14, the motor housing hole forming member 13 and the connecting member 15 of both are integrally formed of metal and embedded in the housing 11 made of resin by molding, so that the insert member 16 is made of resin. It is possible to reinforce the housing 1 and suppress a change in the inner diameter of the intake passage 2 with respect to a temperature change from a low temperature to a high temperature, thereby suppressing a change in the gap with the valve body 4 and improving the control accuracy of the intake flow rate. it can.

  (D) As shown in FIG. 6, the ring body 14 is exposed to the surface of the intake passage 2 in the peripheral region of the portion through which the shaft 3 supporting the valve body 4 penetrates, so that icing is the most problematic. Since a metal material that is directly heated and kept warm is disposed at a certain place, it is possible to speed up the freezing of ice.

  (E) As shown in FIG. 7, the ring body 14 is formed in a “C” shape that terminates in the periphery of the portion through which the shaft 3 that supports the valve body 4 penetrates, so that relatively freezing occurs. Heat can be intensively supplied to a portion around the throttle shaft 3 that is likely to be generated.

  (F) When the controller ECU detects icing on the inner surface of the intake passage 2 of the valve body 4, the applied current value is increased, and the electric motor 5 is driven to promote heat generation. The icing of the valve body 4 can be quickly released.

  (G) The detection of the icing state of the valve body 4 on the inner surface of the intake passage 2 is performed by calculating the deviation between the opening command value for the electric motor 5 and the detected opening value of the valve body 4 and a preset set value of the deviation. By determining by comparing, it is possible to reliably detect icing of the valve body 4 without requiring a temperature sensor or the like.

  (H) Drive that promotes heat generation is executed by continuing the fully closed state in which the valve body 4 is driven in the valve closing direction and brought into contact with the stopper, thereby controlling the valve body 4 in the closing direction. Therefore, it is a control that improves safety more.

1 is a cross-sectional view of an electric throttle valve device showing an embodiment of the present invention. Sectional drawing by the AA line of FIG. Explanatory drawing which shows the application state to the engine of an electric throttle valve. The system block diagram of an electrically controlled throttle valve apparatus. The control flowchart of the electric control throttle valve apparatus performed in an engine control part. Sectional drawing of 2nd Example of an electrically controlled throttle valve apparatus. Sectional drawing of 3rd Example of an electrically controlled throttle valve apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electric control throttle valve apparatus 2 Intake passage 3 Throttle shaft 4 Valve body 5 Electric motor 6 Reduction gear 7 Return spring 8 Throttle opening sensor 10 Motor accommodation hole 11 Body housing 12 Cover 13 Accommodation hole component 14 Ring body, annular part 15 Connecting portion 16 Insert member

Claims (9)

A disk-shaped valve body is fixed to the exposed portion of the cylindrical hole of the shaft that is rotatably disposed through the cylindrical hole constituting the intake passage of the housing, and the shaft is rotated around its axis by an electric motor. In the electric throttle valve device that controls the flow rate by opening and closing the intake passage by the valve body by rotating,
A ring body made of a material having a high thermal conductivity is disposed in the annular inner wall surface of the intake passage facing the peripheral edge of the fully closed valve body and / or the wall surface of the housing surrounding the annular inner wall surface, and the electric motor The case and / or the accommodation hole forming member of the electric motor is formed of a material having high thermal conductivity,
An electric throttle valve device characterized in that the ring body and a motor case and / or a motor housing hole forming member are connected so as to be able to conduct heat, and heat generated by the electric motor is utilized.   The electric throttle valve device according to claim 1, wherein the ring body is embedded in a wall surface of an intake passage made of resin.   The ring body, the motor accommodation hole forming member, and the connecting member of both are integrally formed of metal and embedded in a housing made of resin by molding. Electric throttle valve device.   The electric ring according to any one of claims 1 to 3, wherein the ring body is exposed on a surface of the intake passage in a peripheral region of a portion through which a shaft that supports the valve body passes. Throttle valve device.   5. The ring body according to claim 1, wherein the ring body is formed in a “C” shape that terminates in a periphery of a portion through which a shaft that supports the valve body passes. Electric throttle valve device.   2. The electric motor according to claim 1, wherein when the controller detects icing on the inner surface of the intake passage of the valve body, the applied current value is increased to drive the heat generation. The electric throttle valve device according to claim 5.   The detection of the icing state on the inner surface of the intake passage of the valve body is determined by comparing the deviation between the opening command value for the electric motor and the detected opening value of the valve body with a preset deviation set value. The electric throttle valve device according to claim 6.   The electric throttle valve according to claim 6, wherein the driving for promoting the heat generation is executed by continuing the fully closed state in which the valve body is driven in the valve closing direction and brought into contact with the stopper. apparatus. A shaft that is rotatably disposed through a cylindrical hole that constitutes an intake passage, and a valve body that is fixed to the shaft and rotates together with the shaft. The rotational position of the shaft is controlled by an electric motor, thereby In the electric throttle valve device that adjusts the amount of intake air flowing through the passage,
An electric throttle valve characterized in that a member having high thermal conductivity is disposed in the cylindrical hole, the electric motor and the member are connected so as to be able to conduct heat, and heat generated by the electric motor is transmitted to the member. apparatus.