JP2013185489A - Electronic throttle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem that in the conventional electronic throttle, sliding hysteresis torque due to contact of a coil part of a second spring with an inner circumferential guide of a throttle gear is generated, and return margin torque of a throttle valve between an enclosed opening to an opener opening in which evacuation travel is allowed is lowered, thus this afgfects evacuation travel performance when an electronic throttle fails.SOLUTION: In an electronic throttle, a second spring 12 is arranged at an outward side in a radial direction from a coil part 13 of a first spring 11, so that the second spring 12 does not slide with an inner circumferential guide 23 of a throttle gear 8, thus coating with a lubricant for decreasing sliding hysteresis torque is unnecessary. This makes it possible to decrease manufacturing cost and facilitates local procurement in foreign countries. The axial length of a coil spring 5 can be shortened, allowing an intake throttle valve to be compact. Furthermore, a safe evacuation travel performance can be secured when the electronic throttle fails.

Description

  The present invention relates to an electronic throttle.

[Conventional technology]
Conventionally, a throttle body that forms an intake passage through which intake air that has passed through an air cleaner of an internal combustion engine (engine) flows, a throttle valve that opens and closes the intake passage, and a rotary shaft (throttle shaft) of the throttle valve are coupled to be rotatable together. And a throttle opening for detecting the throttle opening corresponding to the rotation angle of the throttle valve, and an actuator for rotating the throttle shaft to open and close the throttle valve. Electronic throttles with sensors are known.

  In such an electronic throttle, for the purpose of enabling evacuation travel (limp home) when the throttle valve, actuator, throttle opening sensor or the like breaks down (hereinafter referred to as electronic throttle failure), or to the motor in winter, etc. For the purpose of preventing icing of the throttle valve when energization of the engine is stopped, a structure is provided in which the throttle opening is opened to a predetermined opener opening when energization of the motor is stopped and the engine is stopped (for example, a patent References 1-3).

Patent Documents 1 to 3 describe an opener mechanism that opens a throttle valve by an opener opening that allows retreat travel when an electronic throttle fails.
The opener mechanisms of Patent Documents 1 and 2 have a first spring that functions as a return spring when the throttle valve is open at an intermediate position between the fully closed position and the fully open position, and a throttle valve that is below the intermediate position. The coil spring is integrated with a second spring that functions as an opener spring when closed.

The first spring has a coil portion on the outer peripheral side of the first cylindrical sleeve of the throttle body and on the outer peripheral side of the second cylindrical sleeve of the throttle gear.
The second spring has a coil portion on the outer peripheral side of the second cylindrical sleeve.
The coupling portion between the terminal on one end side of the coil portion of the first spring and the terminal on the other end side of the coil portion of the second spring is abutted and locked to an intermediate position stopper that defines the intermediate position of the throttle valve. A U-shaped hook is provided. The U-shaped hook is formed by bending a joint portion between the first spring and the second spring into an inverted U shape.
The first and second cylindrical sleeves constitute inner peripheral guides that hold the inner diameters of the coils of the first and second springs.

In the opener mechanism of Patent Document 3, one end of a return spring arranged around the throttle shaft is hooked on a fixing hook of the throttle body, and the other end of the return spring is connected to a default spring via a spring connecting portion. The connecting portion has one spring hooked to the movable stopper of the throttle gear.
The other end of the default spring is held in a state in which an urging force is applied to a movable hook provided on the throttle gear in a direction to open the throttle valve. As a result, when the electronic throttle breaks down, the opener opening degree (the default position somewhat opened from the fully closed position) at which retreat traveling is possible is maintained.

[Conventional technical problems]
However, in the opener mechanism of Patent Document 1, a sliding hysteresis torque is generated by the contact between the coil portion of the second spring and the inner peripheral guide of the throttle gear, and the opener opening between the fully closed position and the openable opening degree can be reduced. The return allowance torque of the throttle valve is lowered, and the evacuation traveling performance at the time of electronic throttle failure (system failure) is affected.
For this measure, in the opener mechanism of Patent Document 2, Teflon (registered trademark) as an example of a lubricant is coated on the coil portion of the second spring and the second cylindrical sleeve of the throttle gear.

However, since expensive Teflon (registered trademark) is coated, the manufacturing cost of the electronic throttle becomes high, and the manufacturers that can produce it are limited. For this reason, it has become a bottleneck in local procurement overseas (local procurement of electronic throttle components at electronic throttle manufacturing bases outside Japan).
In addition, since two types of first and second springs in which the winding directions of the wires (wires) are opposite to each other are arranged in series in the rotation axis direction of the throttle valve, the first spring and the second spring The length of the coil spring in the direction of the rotation axis (spring length) becomes very long, which is an obstacle to miniaturization of the electronic throttle.

  On the other hand, in the opener mechanism of Patent Document 3, the coil portion of the return spring and the coil portion of the default spring are not arranged in series, and two coil portions having different coil inner diameters and axial cores are necessary. The moldability on the machine is bad. Thereby, since the productivity of the electronic throttle is inferior, there is a problem that the manufacturing cost increases.

Japanese Patent No. 3945568 JP 2004-150324 A JP 2008-190368 A

  An object of the present invention is to provide an electronic throttle that can prevent a decrease in retreat running performance or anti-icing performance of a valve when the electronic throttle fails. Another object of the present invention is to provide an electronic throttle capable of reducing the size of the body by shortening the axial length of the urging means of the valve. Another object of the present invention is to provide an electronic throttle capable of improving productivity and reducing manufacturing costs.

According to the first aspect of the present invention, one urging means in which the first elastic member and the second elastic member are provided continuously, and a guide extending in the direction of the rotation axis of the rotary member that can rotate integrally with the valve. And.
The electronic throttle is set between the fully closed opening and the fully opened opening by the urging force of the first elastic member and the urging force of the second elastic member at the time of stopping energization of the motor and the operation of the internal combustion engine. The valve opening is maintained at a predetermined opener opening.
The first elastic member of the biasing means includes a spiral or spiral coil portion wound so as to surround the outer periphery of the guide of the rotating member. Further, the second elastic member is disposed on the radially outer side than the coil portion of the first elastic member.

Accordingly, since at least the second elastic member does not slide with the guide of the rotating member, it is not necessary to coat the biasing means and the guide of the rotating member with the lubricant for reducing the sliding hysteresis torque. Thereby, manufacturing cost can be reduced.
In addition, since it is not necessary to coat the urging means and the guide of the rotating member with the lubricant, it is easy to make a local arrangement overseas.
Further, since the two first and second elastic members are not arranged in series in the axial direction of the urging means, the entire length of the urging means (the axial length of the urging means) can be shortened, so that the size of the electronic throttle can be reduced. Can be achieved.
In addition, safe evacuation performance can be ensured when the electronic throttle fails. Further, it is possible to prevent a decrease in anti-icing performance of the valve.

According to the second aspect of the present invention, the fixed stopper for defining the opening degree of the valve is provided. That is, the fixed stopper is a holding member that holds (fixes) the opening of the valve at the opener opening.
The first elastic member or the second elastic member contacts the fixed stopper at least when the opening of the valve is between the fully closed opening and the opener opening, that is, when the valve is closed below the opener opening. And is locked. As a result, an urging force that urges the valve in the valve opening direction is generated in an elastic member (for example, the second elastic member) that performs an opener spring function that urges the valve in the valve opening direction.

According to the invention described in claim 5, the two first and second connecting members are arranged on the radially outer side of the second connecting member relative to the rotation axis of the rotating member. Has been placed.
According to invention of Claim 6, the 2nd elastic member is arrange | positioned without the clearance gap in the rotation direction of the 1st connection member and the 2nd connection member.
That is, since the second elastic member does not have a gap (backlash) in the rotation direction of the valve and the rotation member with respect to the first connection member and the second connection member, the valve closing direction of the valve and the valve opening direction of the valve In any direction, there is no dead zone of the opening of the valve, the reproducibility of the opening of the opener during retreat travel is excellent, and safe retreat travel performance can be ensured.

1 is a schematic diagram showing a schematic configuration of an opener mechanism of an electronic throttle system (Example 1). FIG. (Example 2) which is the schematic diagram which showed schematic structure of the opener mechanism of an electronic throttle system. (Example 3) which is the schematic diagram which showed schematic structure of the opener mechanism of an electronic throttle system. (Example 4) which is the schematic diagram which showed schematic structure of the opener mechanism of an electronic throttle system. (Example 5) which is the schematic diagram which showed schematic structure of the opener mechanism of an electronic throttle system.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[Configuration of Example 1]
FIG. 1 shows an opener mechanism (Embodiment 1) of an electronic throttle system to which the present invention is applied.

  The electronic throttle system (hereinafter referred to as electronic throttle) of this embodiment drives a motor (described later) in accordance with the accelerator operation amount of the driver (driver), and sets the throttle opening corresponding to the valve opening of the intake throttle valve. Intake control of an internal combustion engine that controls engine rotational speed or engine torque by changing and variably controlling the flow rate (intake air amount, intake air amount) of intake air supplied to the combustion chamber of each cylinder of the internal combustion engine (engine) Device. The accelerator operation amount corresponds to the depression amount of the driver's accelerator pedal.

The electronic throttle is an intake throttle valve incorporated in the middle of the engine intake pipe, and an engine control unit (electronic) that variably controls the throttle opening in accordance with the engine operating status (for example, accelerator pedal depression amount, accelerator opening). Control device: ECU).
The electronic throttle is applied to a multi-cylinder gasoline engine having a plurality of cylinders. However, the present invention is not limited to a multi-cylinder gasoline engine, and the present invention may be applied to a multi-cylinder diesel engine.

The engine produces an output by heat energy obtained by burning a mixture of clean air filtered by an air cleaner (air cleaner of an internal combustion engine) and fuel injected by an injector (fuel injection valve of the internal combustion engine) in a combustion chamber. It is what happens.
An intake pipe having an intake passage formed therein and an exhaust pipe having an exhaust passage formed therein are connected to the engine.
Here, the intake pipe is composed of a throttle body 1, a surge tank, an intake manifold, and the like, and is connected to an intake port for each cylinder of the engine.

  The intake throttle valve includes a throttle body 1 coupled between an air cleaner and an intake manifold (or surge tank), a valve shaft (hereinafter referred to as a throttle shaft) 2 rotatably supported by the throttle body 1, and the throttle shaft. 2, a butterfly valve (hereinafter referred to as a throttle valve) 3 that is supported and fixed by an actuator 2, an actuator that rotationally drives the throttle shaft 2 to open and close the throttle valve 3, and an opening of the throttle valve 3 (a fully closed opening and a fully opened opening). A fixed stopper 4 that defines an intermediate opening between the fully closed position and an intermediate position slightly opened from the fully closed position, a single coil spring 5 having two different spring functions, and a rotation angle of the throttle valve 3. And a rotation angle detection device for detection.

The rotation angle detection device detects a throttle opening corresponding to the rotation angle of the throttle valve 3 by measuring a rotation angle of the magnet rotor (not shown) rotating in conjunction with the throttle shaft 2 and measuring the rotation angle of the magnet rotor. An opening sensor is provided.
The actuator includes a throttle gear 8 connected to the throttle shaft 2 and the throttle valve 3 so as to be integrally rotatable, and an electric motor (hereinafter referred to as a motor) 9 that rotationally drives the throttle gear 8.

The coil spring 5 has a first spring 11 that functions as a return spring that urges the throttle valve 8 in a closing (full closing) direction with respect to the throttle gear 8, and opens the throttle valve 3 with respect to the throttle gear 8 ( It is a single spring member (biasing means) formed continuously with the second spring 12 that performs the opener spring function of biasing in the fully open direction.
The throttle gear 8 is a spring inner peripheral guide that holds (guides) the inner diameters of the two first and second connecting members 21 and 22 connected to the throttle gear 8 so as to be integrally rotatable and the coil portion 13 of the first spring 11. (Hereinafter referred to as an inner periphery guide) 23 is provided.
Details of the coil spring 5 and the throttle gear 8 will be described later.

The throttle body 1 is integrally formed with a cylindrical intake duct (cylindrical portion) 24 constituting a part of the intake pipe of the engine and a housing for accommodating an actuator including the motor 9 therein.
Inside the intake duct 24, a throttle bore 25 having a circular cross section in which the intake air that has passed through the air cleaner flows is formed. The intake duct 24 includes shaft insertion holes (bearing holes) that extend in the rotational axis direction of the throttle shaft 2 on both sides of the throttle bore 25 in the width direction.
The throttle bore 25 is an air flow path (intake passage) through which intake air supplied to the engine flows and communicates with a combustion chamber for each cylinder of the engine.
The housing is provided with a fixing hook 26 that locks or holds the end of the coil portion 13 of the first spring 11. Further, the housing is provided with a stopper support portion 27 into which the fixed stopper 4 is screwed. The stopper support portion 27 is provided on the rotation locus of the second spring 12.

The throttle shaft 2 extends straight in the rotation axis direction. The throttle shaft 2 is disposed so as to cross the throttle bore 25 in a direction perpendicular to the axial direction (intake flow direction).
The rotation axis of the throttle shaft 2 constitutes the rotation center of the throttle valve 3 and the throttle gear 8.
The throttle shaft 2 is rotatably accommodated in the hole wall surface of the shaft insertion hole of the intake duct 24.

The throttle shaft 2 has a pair of sliding portions that are inserted into sliding holes of a bearing member (bearing) (not shown) and slide with the hole wall surfaces of the sliding holes. Between these sliding portions, a valve support portion for integrally connecting the throttle valve 3 is provided. Further, the throttle shaft 2 has two projecting portions 28 and 29 projecting outward from the outer surface of the intake duct 24 on both sides in the rotational axis direction than the pair of sliding portions.
The magnet rotor and the throttle gear 8 are coupled to one of the two protrusions 28 and 29 so as to be integrally rotatable.

The throttle valve 3 is accommodated in the intake duct 24 (throttle bore 25) so as to be opened and closed, and rotates around the central axis of the throttle shaft 2 to open and close the throttle bore 25.
The throttle valve 3 is fastened and fixed to the throttle shaft 2 by fastening screws while being inserted into a slit hole formed in the throttle shaft 2. As a result, the throttle valve 3 is coupled to the throttle shaft 2 so as to be integrally rotatable.

  The throttle valve 3 is a butterfly that rotates around the rotation shaft of the throttle shaft 2 within an operating range from a fully closed position (fully closed position) to an open position (intermediate position) to a fully opened position (fully opened position). It is a valve. The throttle valve 3 is a disc-shaped plate valve centered on the intersection of the central axis of the throttle bore 25 and the rotational central axis of the throttle valve 3. The throttle valve 3 has a rotation center axis in a direction perpendicular to the axial direction (intake flow direction) of the throttle bore 25.

  The fixed stopper 4 has a head that can be engaged with a tool and a shaft that extends from the head to the spring side, and is configured by an adjustment screw with an intermediate opening adjustment function. The fixed stopper 4 is fixed by screwing a shaft portion so as to protrude from the end surface of the stopper support portion 27 of the housing. Further, the second spring 12 is brought into contact with and engaged with the front end surface of the fixed stopper 4 at the throttle opening from the fully closed opening to the opener opening.

Next, details of the actuator of this embodiment, particularly the throttle gear 8, will be described with reference to FIG.
Here, the actuator that rotationally drives the throttle shaft 2 includes a motor 9 that generates power (torque) when supplied with electric power, and a speed reduction mechanism that transmits the rotation of the motor 9 to the throttle shaft 2 by decelerating the rotation of the motor 9 by two stages. I have.

The reduction mechanism includes a motor gear (hereinafter referred to as pinion gear) 6, an intermediate reduction gear (hereinafter referred to as intermediate gear) 7 that rotates in mesh with the pinion gear 6, and a throttle gear 8 that rotates in mesh with the intermediate gear 7.
The pinion gear 6 has a cylindrical portion fixed to the output shaft of the motor 9. A plurality of convex teeth (pinion gear teeth 31) are formed in the entire circumferential direction on the outer peripheral portion of the cylindrical portion of the pinion gear 6.

The intermediate gear 7 has two annular portions that are rotatably fitted to the outer periphery of an intermediate shaft (not shown). A plurality of convex teeth (large-diameter gear teeth 32) that mesh with the pinion gear teeth 31 are formed in the entire circumferential direction on the outer peripheral portion of the large-diameter annular portion having a large outer diameter between the two annular portions. . A plurality of convex teeth (small-diameter gear teeth 33) meshing with the throttle gear 8 are arranged on the outer peripheral portion of the small-diameter annular portion whose outer diameter is smaller than that of the large-diameter annular portion. It is formed in the entire direction.
The throttle gear 8 is fixed to the throttle shaft 2 while being prevented from rotating. As a result, the throttle gear 8 rotates so as to rotate integrally with the throttle shaft 2 and the throttle valve 3.
On the outer periphery of the maximum outer diameter portion of the throttle gear 8, throttle gear teeth 34 that mesh with the small diameter gear teeth 33 are formed in an arc shape.

The throttle gear 8 is integrally provided with two first and second connecting members 21 and 22 and an inner peripheral guide 23.
The first connecting member 21 is a columnar member that protrudes from the end face of the throttle gear 8 toward the opposite valve side (or the valve side). The first connecting member 21 is disposed more radially inward than the second connecting member 22 with respect to the rotation center of the throttle gear 8. The first connecting member 21 has a first locking portion (hereinafter referred to as a first movable hook) 41 that locks the first spring 11 or the second spring 12.
The first connecting member 21 is elastic to the first spring 11 that performs the return spring function when the throttle opening is between the opener opening and the fully opened opening, that is, when the throttle opening is larger than the opener opening. Force (restoring force in the valve closing direction, valve closing force) is generated.

The second connecting member 22 is a columnar member that protrudes in the same direction as the protruding direction of the first connecting member 21. The second connecting member 22 is disposed on the radially outer side with respect to the rotation center of the throttle gear 8 than the first connecting member 21. The second connecting member 22 has a second locking portion (hereinafter referred to as a second movable hook) 42 for locking the first spring 11 or the second spring 12.
When the throttle opening is between the fully closed opening and the opener opening, that is, when the throttle opening is closed below the opener opening, the second connecting member 22 serves as the second spring 12 that performs the opener spring function. An elastic force (restoring force in the valve opening direction, valve opening force) is generated.
The inner peripheral guide 23 is a cylindrical member (or columnar member) that protrudes from the end face of the throttle gear 8 toward the opposite valve side (or valve side) on the rotation center axis of the throttle gear 8. The inner periphery guide 23 guides (holds) the inner periphery of the coil portion 13 of the first spring 11. The inner peripheral guide 23 has an outer diameter smaller than the inner diameter of the coil portion 13.

The motor 9 is electrically connected to a battery mounted on a vehicle such as an automobile via a motor drive circuit electronically controlled by the ECU.
The ECU includes a CPU having a known structure configured to include functions such as a CPU that performs control processing and arithmetic processing, a control program or control logic, and a storage device (memory such as ROM and RAM) that stores various data, and a timer. A computer is provided.
The ECU uses an A / D converter circuit to output signals from various sensors such as an air flow meter, a crank angle sensor, an accelerator opening sensor, a throttle opening sensor, a cooling water temperature sensor, an intake air temperature sensor, and an intake air pressure sensor. After the conversion, it is configured to be input to the microcomputer.
Here, the ECU calculates a target throttle opening based on an accelerator opening signal that is an output signal of the accelerator opening sensor, and calculates an actual throttle opening and a target throttle opening that are output signals of the throttle opening sensor. The power supplied to the motor 9 is feedback-controlled so that there is no deviation.

Next, details of the coil spring 5 of this embodiment will be described with reference to FIG.
The coil spring 5 is manufactured by forming a single metal wire (a wire having a circular cross section) into a predetermined shape. In the coil spring 5, a first spring 11 that functions as a return spring and a second spring 12 that functions as an opener spring are formed of a single metal wire.
The first spring 11 is a coil-shaped first elasticity that urges the throttle valve 3 in a direction (a valve closing direction) to return the throttle valve 3 from an opening degree larger than the opening degree (opening side opening degree) to the opening degree. It is a member.
The first spring 11 includes a coil portion 13 formed by winding a metal wire in a spiral shape. The coil portion 13 is wound so as to surround the inner periphery guide 23 in a spiral shape.

A first coil end portion 43 is provided on one end side of the coil portion 13 in the winding direction. A second coil end portion 44 is provided on the other end side of the coil portion 13 in the winding direction.
A spring hook 45 that protrudes (extends) from the first coil end portion 43 toward the radially outward side of the coil portion 13 is locked or held by the fixed hook 26 of the housing.
The spring arm 14 that protrudes (extends) from the second coil end portion 44 toward the radially outward side of the coil portion 13 has a first locked portion (contacted and locked to the first movable hook 41). Hook) 51 and a second locked portion (hook) 52 that is locked in contact with the second movable hook 42.

The second spring 12 is integrated with the spring arm 14 and returns the throttle valve 3 from the opening smaller than the opening (opening on the fully closed opening side) to the opening (opening direction). ) Is a second elastic member.
The second spring 12 is configured by a linear portion (straight-shaped metal strand) obtained by extending a metal strand from the second coil end portion 44 of the coil portion 13 toward the radially outer side of the coil portion 13. The spring hook 45 is integrated.
The second spring 12, that is, the spring hook 45, rotates with respect to the rotation center (rotation center axis) of the throttle gear 8 in the rotation direction (clockwise direction (CW direction) and counterclockwise direction of the first and second movable hooks 41 and 42. (CCW direction)) with no gap (displacement).
The spring arm 14 has a function of an opener spring and contacts the fixed stopper 4 at least when the throttle opening is between the fully closed opening and the opener opening, that is, when the throttle opening is equal to or less than the opener opening. And a third locked portion (hook) 53 to be locked.

[Operation of Example 1]
Next, the operation of the electronic throttle of this embodiment will be briefly described with reference to FIG.
When the engine is stopped, the third locked portion 53 of the spring arm 14 is fixed to the fixed stopper 4 that defines the opening degree of the opener that is a neutral position where the biasing force of the first spring 11 and the biasing force of the second spring 12 are balanced. Are locked in contact.
Thus, the throttle shaft 2, the throttle valve 3 and the throttle gear 8 are opened to a predetermined opener opening (for example, in winter) by using the biasing forces of the two types of first and second springs 11 and 12 having different biasing directions. The throttle valve 3 is held at an intermediate opening and an intermediate position where icing can be prevented.

When the throttle valve 3 is opened from the opener opening to an opening larger than the opener opening when the electronic throttle is normal, the rotational power of the motor 9 in the normal rotation direction (counterclockwise in FIG. 1) is the pinion gear. 6 and the intermediate gear 7 are transmitted to the throttle gear 8. Thereby, the throttle valve 3 is opened as the throttle gear 8 rotates.
At this time, the first movable hook 41 of the first connecting member 21 presses the first locked portion 51 of the spring arm 14 against the urging force of the first spring 11. For this reason, as the throttle gear 8 rotates in the valve opening direction, the coil portion 13 of the first spring 11 closes (returns) the throttle valve 3 and the throttle gear 8 from the opening degree that is larger than the opening degree to the opening degree. ) A biasing force that biases in the direction is generated.
When the throttle gear 8 rotates in the opening direction from the opening of the opener, the second spring 12, that is, the spring arm 14, has the first and second movable hooks 41 and 42 of the two first and second connecting members 21 and 22. In order to maintain the state of being sandwiched between them, the urging force of the second spring 12 is not involved.

Further, when the throttle valve 3 is closed from the opener opening to the opening smaller than the opener opening, the rotational power of the motor 9 in the reverse rotation direction (clockwise in FIG. 1) causes the throttle gear 8 to rotate. The throttle valve 3 is closed.
At this time, the second movable hook 42 of the second connecting member 22 resists the urging force of the second spring 12 in a state where the third locked portion 53 of the spring arm 14 is in contact with the fixed stopper 4. The second locked portion 52 of the arm 14 is pressed. For this reason, as the throttle gear 8 rotates in the valve closing direction, the spring arm 14 biases the throttle valve 3 and the throttle gear 8 from the opening degree closed from the opening degree to the opening direction. Occurs.
Note that, when the throttle gear 8 rotates in the closing direction from the opener opening degree, the state where the third locked portion 53 is in contact with the fixed stopper 4 is maintained, so that the urging force of the first spring 11 is not involved.

In the event of an electronic throttle failure, such as when power supply to the motor 9 is interrupted for some reason, the return spring function by the first spring 11, that is, the opening from the opening that opens the throttle gear 8 relative to the opening of the opening. The third locked portion 53 is brought into contact with the fixed stopper 4 by the urging force that urges the opening in the closing direction.
At the same time, the third locked portion 53 is fixed by the opener spring function by the second spring 12, that is, the biasing force that biases the throttle gear 8 in the direction to open the throttle gear 8 from the closed position to the opener position. It abuts against the stopper 4.
As a result, the throttle shaft 2 and the throttle valve 3 are held at a predetermined opener opening (for example, an intermediate opening or an intermediate position at which a vehicle such as an automobile can be evacuated), so that the vehicle is retracted when the electronic throttle fails. Driving is possible.

[Effect of Example 1]
As described above, in the electronic throttle in which the first spring 11 that functions as a return spring and the second spring 12 that functions as an opener spring are formed of a single metal wire, the electronic gear can rotate together with the throttle gear 8. The first and second movable hooks 41 and 42 are provided on the two first and second connecting members 21 and 2, respectively.
Then, the position of the second movable hook 42 is radially outward with respect to the rotation center (rotation center axis) of the throttle gear 8 relative to the position of the first movable hook 41, that is, the second movable hook 42 is second from the first movable hook 41. The movable hook 42 is disposed on the outer peripheral side.

As a result, the second spring 12 and the spring arm 14 do not slide with the outer peripheral surface of the inner peripheral guide 23 of the throttle gear 8, so that a lubricant for reducing the sliding hysteresis torque is applied to the inner peripheral portion of the second spring 12. In addition, since it is not necessary to coat the outer peripheral surface of the inner peripheral guide 23, the manufacturing cost of the electronic throttle can be reduced.
In addition, since it is not necessary to coat the inner peripheral portion of the second spring 12 and the outer peripheral surface of the inner peripheral guide 23 with a lubricant, it is easy to make overseas adjustment.
In addition, since the two first and second springs 11 and 12 are not arranged in series in the axial direction of the coil spring 5, the overall length of the coil spring 5 (coil spring axial length) can be shortened, so that the size of the electronic throttle is small. Can be achieved.

In addition, since the second spring 12 and the spring arm 14 do not slide on the outer peripheral surface of the inner peripheral guide 23 of the throttle gear 8, sliding hysteresis due to contact between the second spring 12 and the inner peripheral guide 23 when the electronic throttle fails. Torque is not generated, and the return margin torque of the throttle valve 3 from the fully closed opening to the retractable opener opening can be prevented from decreasing, so that safe retreat travel performance can be ensured.
In addition, since the throttle valve 3 can be opened by a predetermined opener opening degree when the engine is stopped, the gap between the outer peripheral end of the throttle valve 3 and the inner peripheral surface of the intake duct 24 is a gap that prevents icing. Become. Thereby, the fall of the anti-icing performance of the throttle valve 3 can be prevented.

The second spring 12 and the spring arm 14 are respectively connected to the first and second connecting members 21 and 22 that can rotate integrally with the throttle gear 8 with respect to the rotation center (rotation center axis) of the throttle gear 8. 1. The second movable hooks 41 and 42 are arranged with no gap in the rotational direction (clockwise direction (CW direction) and counterclockwise direction (CCW direction)).
That is, since the second spring 12 and the spring arm 14 do not have a gap (backlash) in the rotational direction of the throttle gear 8 with respect to the first and second movable hooks 41 and 42, the closing direction of the throttle valve 3 and In any direction of the opening direction of the throttle valve 3, there is no dead zone of the throttle opening, the reproducibility of the opening of the opener during the retreat travel is excellent, and safe retreat travel performance can be ensured.

[Example 2]
FIG. 2 shows an electronic throttle opener mechanism (Embodiment 2) to which the present invention is applied. Here, the same reference numerals as those in the first embodiment indicate the same configuration or function, and the description thereof is omitted.

The second spring 12 according to the present embodiment includes at least one folded portion (at least one linear metal wire extending from the second coil end portion 44 of the coil portion 13 toward the radially outer side of the coil portion 13). It is provided by being bent so as to have a U-shaped portion 61).
Specifically, the middle of the spring arm 62 formed of a straight metal wire extending from the second coil end 44 of the coil portion 13 toward the radially outer side of the coil portion 13 is formed in a U shape. The second spring 12 is configured by folding back. In this case, the spring arm 62 has an opener spring function.
The spring arm 62 has a strand length twice that of the spring arm 14 of the first embodiment.
The spring arm 62 is a hairpin type spring portion obtained by bending a metal strand at least once.

As described above, the electronic throttle of this embodiment has the same effect as that of the first embodiment.
In this case, the spring constant and generated torque of the second spring 12 can be easily changed and adjusted. In addition, the rigidity and the spring constant of the 2nd spring 12 can be raised, so that the frequency | count of folding in the 2nd spring 12 increases. Further, as the spring constant of the second spring 12 is increased, the torque generated by the second spring 12 is increased.

[Example 3]
FIG. 3 shows an opener mechanism (Embodiment 3) of an electronic throttle to which the present invention is applied. Here, the same reference numerals as those in the first and second embodiments indicate the same configuration or function, and the description thereof will be omitted.

In the second spring 12 of this embodiment, at least one bent portion 63 of a straight metal wire extending from the second coil end portion 44 of the coil portion 13 toward the radially outer side of the coil portion 13 is used. It is provided by bending.
The second spring 12 is bent so as to be inclined by a predetermined inclination angle from the second locked portion 52 that contacts the second movable hook 42 of the second connecting member 22.

As described above, the electronic throttle of this embodiment has the same effects as those of the first and second embodiments.
Further, for the purpose of increasing (changing) the spring constant of the second spring 12, even when the length of the metal wire of the second spring 12 is increased, the turning radius of the second locked portion 52 is reduced, A compact rotation trajectory can be achieved.
Moreover, when changing the rotation radius of the 2nd to-be-latched part 52, the spring diameter of the 2nd spring 12 does not need to be enlarged.

[Example 4]
FIG. 4 shows an opener mechanism (Embodiment 4) of an electronic throttle to which the present invention is applied. Here, the same reference numerals as in the first to third embodiments indicate the same configuration or function, and the description thereof is omitted.

The second spring 12 of the present embodiment crushes a metal wire having a circular cross section that extends from the second coil end 44 of the coil portion 13 of the first spring 11 toward the radially outer side of the coil portion 13. It is comprised by the metal strand (plate spring) 64 of the flat plate-shaped cross section shape | molded by this.
Even if the single coil spring 5 is configured by welding and integrating the metal wire, which is a separate part with respect to the first spring 11, to the second coil end portion 44 of the coil portion 13. good. Moreover, you may comprise a U-shaped plate spring by folding the metal strand 64 in at least one place.
As described above, the electronic throttle of this embodiment has the same effects as those of the first to third embodiments.
In the case of this embodiment, the spring constant and generated torque of the second spring 12 can be adjusted with a higher degree of freedom.

[Example 5]
FIG. 5 shows an opener mechanism (Embodiment 5) of an electronic throttle to which the present invention is applied. Here, the same reference numerals as in the first to fourth embodiments indicate the same configuration or function, and the description thereof is omitted.

The second spring 12 of the present embodiment surrounds the periphery of an axis extending outward in the radial direction (axial right angle) perpendicular to the rotation axis direction (rotation axis direction) of the inner peripheral guide 23 of the throttle gear 8. A spiral (or spiral) metal element wire (coil part) 65 is formed. The coil portion 65 is wound from the winding start portion at the tip of the spring arm 14 to the winding end portion that comes into contact with and is locked by the fixed stopper 4. The third locked portion 53 of the second spring 12 is provided at the winding end portion (coil end portion) of the coil portion 65.
The flat metal wire extending outward in the radial direction (right angle to the axis) perpendicular to the rotation axis direction (rotation axis direction) of the inner peripheral guide 23 of the throttle gear 8 is folded at at least one place. A U-shaped plate spring may be configured.
As described above, the electronic throttle of this embodiment has the same effects as those of the first to fourth embodiments.
In the case of this embodiment, the spring constant and generated torque of the second spring 12 can be adjusted with a higher degree of freedom.

[Modification]
In this embodiment, the first spring 11 that performs the return spring function is provided as the first elastic member that performs either the return spring function or the opener spring function. A first spring that performs a spring function may be provided.
In the present embodiment, the second spring 12 that performs the opener spring function is provided as the second elastic member that performs either the return spring function or the opener spring function. A second spring that performs a spring function may be provided.

Further, as the coil portion 13 of the first spring 11 or the coil portion 65 of the second spring 12, an equal-pitch coil having the same coil outer diameter in the central axis direction and the same interval between the wires (wires), or the outside of the coil Non-uniform pitch coils whose diameters are the same in the central axis direction and the spacing of the strands (wires) is changed, or non-linear springs whose coil outer diameter changes in the central axis direction (for example, hourglass springs, saddle springs, conical shapes) An elastic member such as a spring) may be employed.
Further, as the coil portion 13 of the first spring 11 or the coil portion 65 of the second spring 12, not only a cylindrical coil spring but also a conical coil spring or a spiral spring may be adopted.

In the present embodiment, the coil portion 13 of the first spring 11 is wound so as to spirally surround the outer periphery of the inner peripheral guide 23 of the throttle gear 8, but the coil portion 13 of the first spring 11 is wound around the throttle gear 8. The inner circumference guide 23 may be wound so as to surround the outer circumference of the inner circumference guide 23 in a spiral shape.
Further, the inner peripheral guide 23 of the throttle gear 8 may be formed in a cylindrical sleeve shape, and the throttle shaft 2 may be inserted into a through hole formed inside. In this case, an inner peripheral guide that holds (guides) the inner diameter of the coil portion 13 of the first spring 11 is formed on the outer periphery of the bearing sleeve (bearing holding portion that holds the bearing member) of the throttle body 1.

2 Throttle shaft (rotating member)
3 Throttle valve 4 Fixed stopper 5 Coil spring (biasing means)
8 Throttle gear (rotating member)
9 Motor 11 First spring (first elastic member)
12 Second spring (second elastic member)
13 Coil part of first spring 23 Inner circumference guide

Claims (11)

(A) a valve (3) for opening and closing an air flow path (25) formed in the intake pipe (24) of the internal combustion engine;
(B) a rotating member (2, 8) that can rotate integrally with the valve (3), and a motor (9) that rotationally drives the rotating member (2, 8);
An actuator for opening and closing the valve (3) via the rotating member (2, 8);
(C) A first elastic member that performs one of a return spring function that biases the valve (3) in the valve closing direction and an opener spring function that biases the valve (3) in the valve opening direction. (11) and a second elastic member (12) that performs the other function of the return spring function or the opener spring function,
A first urging means (5) in which the first elastic member (11) and the second elastic member (12) are continuously provided;
When the energization of the motor (9) is stopped and when the operation of the internal combustion engine is stopped, the fully closed opening degree is determined by the urging force of the first elastic member (11) and the urging force of the second elastic member (12). In an electronic throttle that holds the opening of the valve (3) at a predetermined opener opening set between the fully opened opening,
The rotating member (2, 8) has a guide (23) extending in the rotation axis direction thereof,
The first elastic member (11) has a spiral or spiral coil portion (13) wound so as to surround the outer periphery of the guide (23),
The electronic throttle according to claim 1, wherein the second elastic member (12) is disposed radially outward from the coil portion (13). The electronic throttle according to claim 1, wherein
A fixed stopper (4) for defining the opener opening of the valve (3);
The first elastic member (11) or the second elastic member (12) includes the fixed stopper (4) when at least the opening of the valve (3) is between the fully closed opening and the opener opening. An electronic throttle characterized by being brought into contact with and locked. The electronic throttle according to claim 2,
The first elastic member (11) is provided with a spring arm (14) that extends from the end of the coil portion (13) on the second elastic member (12) side toward the radially outer side. Have
The spring arm (14) has the function of the second elastic member (12), and at least when the opening of the valve (3) is between the fully closed opening and the opener opening, An electronic throttle having a locked portion (53) locked in contact with the fixed stopper (4). The electronic throttle according to any one of claims 1 to 3,
Two first and second connecting members (21, 22) connected to the rotating members (2, 8) so as to be integrally rotatable,
The first elastic member (11) or the second elastic member (12) is configured such that the first connecting member (at least when the opening of the valve (3) is between the opener opening and the fully opened opening). 21), and the second connecting member (when the opening degree of at least the valve (3) is between the fully closed opening degree and the opening degree of the opener). 22) An electronic throttle characterized by having a second locked portion that is locked in contact with 22). The electronic throttle according to claim 4,
The two first and second connecting members (21, 22) are arranged with respect to the rotation axis of the rotating member (2, 8) than the first connecting member (21). The electronic throttle is characterized by being arranged radially outward. The electronic throttle according to claim 4 or claim 5,
The electronic throttle, wherein the second elastic member (12) is disposed without any gap in the rotation direction of the first connecting member (21) and the second connecting member (22). The electronic throttle according to any one of claims 1 to 6,
The electronic throttle according to claim 2, wherein the second elastic member (12) is constituted by a linear element wire extending outward in the radial direction of the coil portion (13). The electronic throttle according to any one of claims 1 to 6,
The second elastic member (12) is provided by bending a linear element wire extending outward in the radial direction of the coil portion (13) with at least one bent portion. An electronic throttle characterized by that. The electronic throttle according to any one of claims 1 to 6,
The second elastic member (12) is provided by bending a linear element wire extending outward in the radial direction of the coil portion (13) at at least one folded portion. An electronic throttle characterized by that. The electronic throttle according to any one of claims 1 to 6,
The second elastic member (12) is configured to couple a wire formed as a separate part to the first elastic member (11) to the first elastic member (11) or to the first elastic member (11). An electronic throttle comprising a flat cross-section element wire formed by crushing a circular cross-section element wire extended from the terminal of (1). The electronic throttle according to any one of claims 1 to 6,
The second elastic member (12) is composed of a spiral or spiral strand wound around the axis extending outward in the radial direction perpendicular to the axial direction of the guide (23). Electronic throttle characterized by being.

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