JP3286231B2 - Throttle valve device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a throttle valve device suitably used for variably controlling an intake air amount of, for example, an automobile engine according to an accelerator operation amount and the like, and in particular, to an actuator such as an electric motor. And a throttle valve device configured to open and close the throttle valve using the same.

[0002]

2. Description of the Related Art Generally, as a throttle valve device,
A throttle body provided in the middle of an intake pipe of the engine and having an intake passage formed therein; and a throttle body rotatably provided on the throttle body via a valve shaft. The intake passage is opened and closed according to the rotation of the valve shaft. A throttle valve to be driven, an electric motor provided on the throttle body for driving the throttle valve, and between the driving means and the valve shaft for decelerating the driving force of the electric motor to the valve shaft. There is known a mechanism comprising a reduction gear mechanism provided (for example, Japanese Patent Application Laid-Open No. 2-500677, Japanese Unexamined Patent Application Publication No.
No. 203219).

[0003] In this type of conventional throttle valve device, a first biasing means for constantly biasing the throttle valve toward a fully closed position is provided, and the throttle valve is moved between a fully open position and a fully closed position. And a second urging means for applying an urging force to the throttle valve in a direction opposite to the first urging means in order to urge toward the intermediate opening position.

Here, when the throttle valve is opened by the electric motor, the torque of the electric motor is transmitted to the valve shaft of the throttle valve via the reduction gear mechanism, and the valve shaft is transmitted to the first biasing means. Rotate in opposition. And
The throttle valve variably controls the rotational output of the engine by changing the intake air amount of the engine according to the valve opening.

Further, when the engine is stopped (when the electric motor is not energized) or when the electric motor fails, the throttle valve is moved from the intermediate opening position to the fully closed position by the first urging means. When rotated, the second urging means applies reverse rotational power to the throttle valve to hold the throttle valve at the intermediate opening position against the first urging means. I have.

[0006]

In the prior art described above, the throttle valve is normally biased in the valve closing direction by the first biasing means, and the throttle valve is opened to the intermediate opening by the second biasing means. Since the springs are urged toward the position, the first and second urging means need to be constituted by two different springs, and the number of parts increases, and the workability at the time of assembly decreases. There is a problem.

In addition, since two springs are provided in the throttle body, there are restrictions on the layout, and it is difficult to reduce the size of the entire device to make it compact.
Further, when the throttle valve is driven by the electric motor in the valve opening direction larger than the intermediate opening position and when the throttle valve is driven in the valve closing direction, the load torque acting on the electric motor (first and second urging means) The spring force) changes, and the adjustment of the opening of the throttle valve by the electric motor tends to vary.

The present invention has been made in view of the above-mentioned problems of the prior art, and the present invention can urge a throttle valve to an intermediate opening position by using a single urging means, and can reduce the number of parts during assembly. It is an object of the present invention to provide a throttle valve device capable of improving the workability of the present invention, reducing the size of the entire device to make it compact, and stabilizing the opening adjustment.

[0009]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a throttle body having an intake passage formed therein, and a throttle body rotatably provided on the throttle body via a valve shaft. A throttle valve for opening and closing a passage; a driving means provided on the throttle body for driving the throttle valve; and a driving means and a valve for reducing a driving force by the driving means and transmitting the driving force to a valve shaft of the throttle valve. The present invention is applied to a throttle valve device including a reduction gear mechanism provided between a shaft and a shaft.

A feature of the structure adopted by the invention of claim 1 is that the speed reducing gear mechanism has a cam surface that allows the throttle valve to rotate between a fully closed position and a fully open position. A cam lever having a bent portion for holding the throttle valve at the intermediate opening position, and a rotatably provided on the throttle body, and rotating in contact with the cam surface of the cam lever. Cam follower,
The cam follower is constantly urged toward the cam surface of the cam lever, and when the driving force of the driving means is released, the cam follower is urged toward the bent portion side of the cam surface to thereby cause the cam lever to move. And a biasing means for holding the throttle valve at the intermediate opening position through the second opening.

With such a configuration, the reduction gear mechanism transmits the driving force from the driving means to the valve shaft of the throttle valve and also to the cam lever, and moves the cam lever between the fully closed position and the fully opened position of the throttle valve. Rotate. At this time, the cam follower follows the movement of the cam lever against the biasing force from the biasing means, is rotated along the cam surface, and is biased against the rotation of the cam lever (throttle valve). Gives a reaction force due to the urging force. And
When the driving force of the driving means is released, the urging means urges the cam follower toward the bent portion of the cam lever, thereby rotating the cam lever via the cam follower, and the cam follower is moved by the cam lever. In this state, the rotation of the cam lever is stopped at the position in contact with the bent portion, and in this state, the throttle valve can be held at the intermediate opening position corresponding to the bent portion.

Further, in the invention according to claim 2, the speed reduction gear mechanism is provided at a drive gear side and a drive gear provided at an end of the valve shaft to transmit rotation of the drive gear to the valve shaft. A driven gear, and the driven gear is integrated with the valve shaft together with the cam lever.

Thus, when the driven gear is rotated by the driving force from the driving gear, the valve shaft of the throttle valve and the cam lever are integrally rotated and the throttle valve is moved between the fully closed position and the fully open position. The cam lever can be rotated between them.

Further, according to the third aspect of the present invention, the cam lever has a fitting hole fitted into the end of the valve shaft in a detented state, and the cam surface is radially separated from the fitting hole. The cam lever is formed by a long hole having a V-shaped bent part at an intermediate position.

Thus, the cam follower can be rotated along the long hole of the cam lever, and when the driving force of the driving means is released, the cam follower is engaged with the V-shaped bent portion by the urging force of the urging means. Accordingly, the rotation of the cam lever can be stopped.

In the invention according to claim 4, the elongated hole of the cam lever has an arc-shaped elongated hole extending radially away from the fitting hole and extending in the circumferential direction. It is formed of a short hole connected to the long hole through the bent portion and is formed to be short, and the short hole and the long hole have a maximum separation distance from the fitting hole at the position of the bent portion. , And has a hole shape that approaches the fitting hole as the distance from the bent portion increases.

Thus, the biasing force of the biasing means can be set to a minimum when the cam follower is engaged with the bent portion of the cam lever, and the biasing force at this time stops the throttle valve at the intermediate opening position. be able to. Then, for example, when the throttle valve is turned from the intermediate opening position to the fully opened position, the cam follower is turned along the long hole of the cam lever, and the urging force of the urging means is gradually increased accordingly. Can increase. When the throttle valve is turned from the intermediate opening position to the fully closed position, the cam follower is turned along the short hole of the cam lever, and the urging force of the urging means is gradually increased accordingly. it can.

According to the fifth aspect of the present invention, the cam lever and the driven gear are formed as separate members, and the rotation center side of the driven gear is fitted to the end of the valve shaft in a detented state. It is configured to have a fitting hole.

Thus, the driven gear and the cam lever can be fitted to the end of the valve shaft through the respective fitting holes in a detented state. In this state, the driven gear and the cam lever are connected to the valve shaft by, for example, a nut. Can be fixed.

On the other hand, according to the invention of claim 6, the cam lever is provided with the elongated hole and the driven gear integrally provided at positions spaced apart in the circumferential direction. Thereby, the cam lever and the driven gear can be formed as a single part.

According to a seventh aspect of the present invention, the driving means comprises an electric motor provided in a throttle body, and the reduction gear mechanism comprises a driving gear fixed to an output shaft of the electric motor, and the valve shaft. A driven gear fixed to the end of the
An intermediate gear provided between the driven gear and the driving gear and transmitting the rotation of the driving gear to the driven gear.

Thus, the rotational force of the electric motor can be reduced and transmitted from the driving gear to the intermediate gear, and the rotation of the intermediate gear can be reduced and transmitted to the driven gear to reduce the output torque of the electric motor. Can be.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a throttle valve device according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

Here, FIGS. 1 to 12 show a first embodiment of the present invention.
Is shown. In the figure, reference numeral 1 denotes a throttle body which forms an outer shell of a throttle valve device. The throttle body 1 is formed by using means such as aluminum die casting, and communicates with the inside of an engine cylinder (not shown). A throttle chamber 1A is formed as an intake passage.

Further, a motor housing case 1B for the electric motor 4 to be described later is formed integrally with the throttle body 1 at a position separated from the throttle chamber 1A by a certain distance. Further, a gear case 1C is formed integrally with the throttle body 1 at one end of a valve shaft 2 described later, and a sensor case 1D is formed integrally with the other end of the valve shaft 2.

Reference numeral 2 denotes a valve shaft rotatably provided on the throttle body 1 via a bearing or the like. The valve shaft 2 is made of a high-strength metal rod or the like, and has a diameter inside the throttle chamber 1A of the throttle body 1. Extending through the direction. And
One end of the valve shaft 2 projects into the gear case 1C, and the other end projects toward the sensor case 1D. Further, the valve shaft 2 is integrated with a throttle valve 3 described later at an intermediate portion in the longitudinal direction, and is configured to open and close the throttle valve 3.

Reference numeral 3 denotes a throttle valve rotatably provided in a throttle chamber 1A of a throttle body 1 via a valve shaft 2. The throttle valve 3 is formed of a disc-shaped valve plate, and has an outer diameter dimension. This corresponds to the inner diameter of the throttle chamber 1A. And the throttle valve 3 is shown in FIG.
It is rotated between a fully closed position indicated by an imaginary line and a fully opened position shown in FIG. 7, and variably adjusts an intake air amount of the engine according to the degree of opening.

Reference numeral 4 denotes an electric motor as driving means housed in the motor housing case 1B. The electric motor 4 comprises, for example, a DC motor or the like, and has an output shaft 4A protruding toward the gear case 1C. I have. And the electric motor 4
Drives the output shaft 4A by power supply from the outside, and moves the valve shaft 2 through arrows A and B in FIG.
The throttle valve 3 opens and closes.

Reference numeral 5 denotes a reduction gear mechanism located in the gear case 1C and disposed between the output shaft 4A of the electric motor 4 and the valve shaft 2. The reduction gear mechanism 5 is shown in FIGS. As shown, a small-diameter drive gear 6 fixed to the output shaft 4A of the electric motor 4, a driven gear 8 fixed to one end of the valve shaft 2 together with a cam lever 11 described later via a nut 7, and an intermediate gear described later 9. The reduction gear mechanism 5 reduces the rotation of the electric motor 4 between the drive gear 6 and the intermediate gear 9, and further reduces the rotation between the intermediate gear 9 and the driven gear 8. To transmit a large rotational driving force to the motor.

Here, the driven gear 8 is shown in FIGS.
As shown in FIG. 3, the sector gear is formed as a sector gear having a substantially fan shape and a diameter larger than that of a small-diameter gear portion 9B described later, and a non-circular fitting hole 8A is formed in the rotation center O side. The driven gear 8 is fitted to one end of the valve shaft 2 via a fitting hole 8A in a non-rotating state, and is fastened to the valve shaft 2 with a nut 7 as shown in FIG. And it is configured to rotate integrally.

Reference numeral 9 denotes an intermediate gear constituting a part of the reduction gear mechanism 5. The intermediate gear 9 is located between the driving gear 6 and the driven gear 8 as shown in FIG. 1C is rotatably mounted via a support shaft 10. The intermediate gear 9 is composed of a large-diameter gear portion 9A and a small-diameter gear portion 9B.
As shown in the figure, the gears are engaged with a constant reduction ratio. The small-diameter gear portion 9B of the intermediate gear 9 meshes with the driven gear 8 at a constant reduction ratio as shown in FIGS. 3 and 4, and gives a large rotational torque to the driven gear 8.

Reference numeral 11 denotes a cam lever fixed to one end of the valve shaft 2 together with the driven gear 8, and the cam lever 11 is formed into a substantially sector shape by pressing a high-strength metal plate as shown in FIGS. 9 and 10. A non-circular fitting hole 11 </ b> A is formed in the rotation center O side, like the driven gear 8. The cam lever 11 is also fitted to one end of the valve shaft 2 via the fitting hole 11A together with the driven gear 8 in a detented state, and is fastened to the valve shaft 2 with a nut 7 as shown in FIG. Further, the cam lever 11 is formed with a long hole 12 which is spaced apart from the fitting hole 11A in the radial direction and forms a cam surface.
A roller 17 described below is rotatably inserted into the elongated hole 12.

As shown in FIG. 9, the long hole 12 of the cam lever 11 has a long hole 12A extending in the circumferential direction of the cam lever 11, and a short hole formed shorter than the long hole 12A. 12B, the short hole 12B and the long hole 12A.
And a bent portion 12C having a substantially V-shape located between the two.

The dimensional relationship of the elongated hole 12A will be described. The distance from the fitting hole 11A (the center of rotation O) is the largest dimension L1 on the side of the bent portion 12C, and is opposite to the bent portion 12C. A fitting hole 11A is provided on the tip edge 12D side.
The long hole portion 12A is formed as an arc-shaped hole having a fixed curvature so that the distance from the hole 12 becomes the minimum dimension L2. As a result, the roller 17 provided on the load lever 14 described later is smoothly guided along the elongated hole 12A between the bent portion 12C and the front edge 12D.

The short hole 12B also has the end on the side of the bent portion 12C farthest away from the fitting hole 11A, and the opposite end extends in the direction approaching the fitting hole 11A. further,
The cam lever 11 has a fitting hole 11A on the side opposite to the long hole 12.
A bent claw portion 11B is integrally formed at a position radially separated from the bent portion, and the bent claw portion 11B comes into contact with a stopper 20, which will be described later, as shown in FIG. It is configured to regulate as shown in FIG.

Reference numeral 13 denotes a fixed pin implanted on the gear case 1C side at a position radially separated from the cam lever 11;
Is a load lever as a cam follower rotatably mounted on the fixing pin 13 via a bearing 15 or the like. The load lever 14 is made of a high-strength metal plate or the like, and is indicated by an arrow C shown in FIG. The urging force (turning power) in the direction
8. A roller 17 is rotatably mounted on the distal end side of the load lever 14 via a support shaft 16, and the roller 17 is inserted into the elongated hole 12 of the cam lever 11.

Here, the roller 17 of the load lever 14 is
The long hole 1 is generated by the urging force of the spring 18 in the direction of arrow C.
When the cam lever 11 is rotated in the directions indicated by arrows A and B, the urging force (reaction force) of the spring 18 is applied to the cam lever 11. The roller 17 contacts the peripheral wall of the elongated hole 12 and rotates, thereby suppressing the frictional resistance between the cam lever 11 and the load lever 14 (the roller 17).

On the base end side of the load lever 14, a hook 14A is protruded at a position opposite to the roller 17, and a spring 18 is hooked on the hook 14A. The load lever 14 is configured such that the roller 17 is
The cam 18 is rotated following the rotation of the cam lever 11 by continuously contacting the peripheral wall of the cam lever 11 to elastically extend (tension) the spring 18 from the preset state shown in FIG. 2 as shown in FIG. 3 or FIG. is there.

Reference numeral 18 denotes a spring serving as an urging means. The spring 18 is located between the engaging projection 19 formed in the gear case 1C and integrally formed on the throttle body 1 and the engaging portion 14A of the load lever 14. Is installed in a preset state. The spring 18 is constituted by a tension spring, and constantly applies a biasing force in the direction of arrow C to the load lever 14.

The spring 18 is connected to the cam lever 1
Also, when the rotational driving force from the electric motor 4 with respect to 1 is released, the load lever 14 is urged in the direction of arrow C so that the roller 17 of the load lever 14 is directed toward the bent portion 12C of the elongated hole 12. Cam lever 11 so that
Is forcibly rotated. As a result, the cam lever 11 is
As shown in FIG. 5, the roller 17 stops rotating at a position where it comes into contact with the bent portion 12C of the elongated hole 12, and at this time, the throttle valve 3 is held at the intermediate opening position shown in FIG.

That is, when the cam lever 11 is rotated from the position shown in FIG. 2 in the direction of arrow A, the roller 17 of the load lever 14 is turned into the short hole 12 of the long hole 12 as shown in FIG.
At this time, the throttle valve 3 is rotated to the closed position shown in FIG. When the cam lever 11 is rotated from the position shown in FIG. 2 in the direction of arrow B, the roller 17 of the load lever 14 comes into contact with the long hole 12A of the long hole 12 as shown in FIG. The throttle valve 3 is turned to the valve opening position (full open position) shown in FIG.

Reference numeral 20 denotes a stopper for restricting the closing position of the throttle valve 3. The stopper 20 is located in the gear case 1C and integrally formed with the throttle body 1 as shown in FIGS. 21, an eye bolt 22 screwed to the stopper projection 21, and a nut 23 screwed to the eye bolt 22. The tip end of the eyebolt 22 is the cam lever 11
3 and the throttle valve 3 indicated by a solid line in FIG. 6 is closed (in the direction of arrow A).
To restrict further rotation.

Here, the stopper 20 changes the screwing position of the eye bolt 22 to the stopper projection 21 with the nut 23 loosened, so that the amount of projection of the eye bolt 22 toward the bending claw portion 11B of the cam lever 11 is appropriately adjusted. It is adjusted to. The valve closing position of the throttle valve 3 is variably adjusted according to the amount of protrusion of the eyebolt 22, for example, between a valve closing position indicated by a solid line in FIG. 6 and a fully closed position indicated by a virtual line.

In the valve closing position indicated by the solid line in FIG. 6, in order to allow the air having the intake air amount corresponding to the idling speed of the engine to flow to the combustion chamber side, the valve is shifted from the fully closed position indicated by the imaginary line. Also, the closing position of the throttle valve 3 is changed by the necessary angle. Stopper 2
The nut 23 constituting a part of the bolt 0 is screwed again to the eyebolt 22 after adjusting the amount of protrusion of the eyebolt 22, and gives the eyebolt 22 a function of preventing loosening.

Reference numeral 24 denotes a gear case 1 of the throttle body 1.
C is a cover detachably provided on the C side.
As shown in FIG. 1, the gear case 1C is covered with the reduction gear mechanism 5 and the like housed in the gear case 1C to prevent rainwater or the like from entering the gear case 1C. 2 to 4 show a state in which the cover 24 is removed from the gear case 1C to clearly show the reduction gear mechanism 5 and the like.

Reference numeral 25 denotes an accelerator operation amount detecting device provided on the throttle body 1;
5 is a wire drum 26 and a return spring 27 as shown in FIG.
And an operation amount sensor 30 described later. A distal end of a wire 28 is wound around the wire drum 26, and a proximal end of the wire 28 is connected to an accelerator pedal (not shown) of the vehicle.

When the driver of the vehicle depresses the accelerator pedal, the wire drum 26 moves the return spring 2
7, the accelerator operation amount is controlled by the operation amount sensor 3
It is conveyed to 0. The accelerator operation amount detection device 25
Is provided with a wire guide 29.
Is for smoothly guiding the wire 28 to be unwound from or wound on the wire drum 26.

Reference numeral 30 denotes an operation amount sensor constituted by a potentiometer or the like. The operation amount sensor 30 detects the rotation of the wire drum 26 as an accelerator operation amount, and outputs a detection signal to a control unit (not shown) for controlling the engine. Output to The control unit outputs a drive signal corresponding to the accelerator operation amount to the electric motor 4 in accordance with the detection signal from the operation amount sensor 30, and drives the electric motor 4 to rotate the throttle valve 3.
Is rotated by an opening corresponding to the accelerator operation amount.

Reference numeral 31 denotes a throttle sensor provided on the sensor case 1D side of the throttle body 1. The throttle sensor 31 is constituted by a potentiometer or the like in substantially the same manner as the operation amount sensor 30, and controls the rotation angle of the valve shaft 2. This is detected as an opening of the throttle valve 3 (hereinafter, referred to as a throttle opening).

The throttle valve device according to the present embodiment has the above-described configuration. Next, the operation of the throttle valve device will be described.

First, when the driver of the vehicle depresses the accelerator pedal, the operating force at this time is reduced by the wire 28.
Of the accelerator operation amount detecting device 25 via the wire drum 2
The wire drum 26 is rotated by an angle corresponding to the accelerator operation amount against the return spring 27.

When the operation amount sensor 30 detects the rotation of the wire drum 26 (accelerator operation amount), a detection signal is output to a control unit for engine control, and the control unit responds to the detection signal from the operation amount sensor 30. A drive signal corresponding to the accelerator operation amount is output to the electric motor 4.

As a result, the electric motor 4 is driven to rotate in one direction, and the rotational force of the electric motor 4 is reduced by the reduction gear mechanism 5, so that a large rotational torque is transmitted to the valve shaft 2. Then, the throttle valve 3 is rotated integrally with the valve shaft 2 as shown in FIGS. 5 to 7, and the opening thereof is controlled so as to correspond to the accelerator operation amount.

Further, the cam lever 11 fixed to the valve shaft 2 together with the driven gear 8 of the reduction gear mechanism 5 rotates integrally with the valve shaft 2, and when the throttle valve 3 shown in FIG. By rotating in the direction of arrow B, the load lever 14 is rotated as shown in FIG. 4 along the elongated hole 12A of the elongated hole 12 forming the cam surface. The power is increased.

On the other hand, in the closed position of the throttle valve 3 shown in FIG. 6, the cam lever 11 is rotated together with the valve shaft 2 in the direction indicated by the arrow A, so that the load lever 14 is moved into the elongated hole 12 as shown in FIG. It is rotated along the short hole 12B, and during this time, the urging force of the spring 18 is increased.

When the power supply to the electric motor 4 is cut off when the engine is stopped or the like and the rotational driving force to the reduction gear mechanism 5 is released, the urging force of the spring 18 causes an arrow C around the fixed pin 13. A turning force in the direction is applied to the load lever 14. Then, the load lever 14 relatively rotates the cam lever 11 so that the roller 17 is guided to the bent portion 12C side of the elongated hole 12. As a result, the roller 17 is turned into the long hole 1 as shown in FIG.
The rotation of the throttle valve 3 is stopped at a position where the throttle valve 3 comes into contact with the second bent portion 12C. At this time, the throttle valve 3 is held at the intermediate opening position shown in FIG.

That is, the cam lever 11 is stopped by the valve shaft 2 through the fitting hole 11A on the rotation center O side. Then, as shown in FIG. 9, the long hole 12A and the short hole 1 of the long hole 12 are formed.
2B means that the distance from the fitting hole 11A is
It has a maximum dimension L1 at the position C, and has a hole shape in which the distance from the fitting hole 11A gradually decreases as the distance from the bent portion 12C increases.

As a result, when the rotational force of the electric motor 4 is released, the cam lever 11 can be automatically rotated to the position shown in FIG. 2 by the urging force of the spring 18 via the load lever 14, and the throttle valve 3 is released. It is possible to automatically return to the intermediate opening position shown in FIG.

Thus, according to the present embodiment, the motor housing case 1B is integrally provided in the throttle body 1 apart from the throttle chamber 1A, and the electric motor 4 is provided in the motor housing case 1B. And
An output shaft 4A of the electric motor 4 is projected into a gear case 1C provided on one side of the throttle body 1, and a reduction gear mechanism 5 is provided between the output shaft 4A and the valve shaft 2 of the throttle valve 3. Is provided.

As a result, the rotation of the electric motor 4 can be reduced by the reduction gear mechanism 5 to generate a large rotational torque on the valve shaft 2. Even when the small electric motor 4 having a small output torque is used, the throttle valve 3 can be used. Opening and closing can be reliably performed via the valve shaft 2. For this reason, the electric motor 4 can be made a small motor to reduce the driving torque, save energy, and smoothly control the amount of intake air according to the opening of the throttle valve 3.

Further, the reduction gear mechanism 5 is disposed in the gear case 1C of the throttle body 1, and includes a driving gear 6 fixed to the output shaft 4A of the electric motor 4, and a driven gear 8 fixed to the valve shaft 2. And the intermediate gear 9 composed of a large-diameter gear portion 9A meshed with the drive gear 6 and a small-diameter gear portion 9B meshed with the driven gear 8, so that the reduction ratio of the reduction gear mechanism 5 can be increased, and the gear case can be increased. The reduction gear mechanism 5 can be housed in the 1C compactly, and the entire throttle valve device can be reduced in size and weight.

Further, in the gear case 1C, a cam lever 11 is fixedly provided so as to be sandwiched between the driven gear 8 and the nut 7 on one end side of the valve shaft 2, and a roller 17 on the tip side is provided with a cam lever 11. A load lever 14 as a cam follower inserted into the long hole 12 is rotatably provided via a fixing pin 13 or the like. The load lever 14 is provided with a single spring 18 that constantly biases the roller 17 toward the outer peripheral wall of the elongated hole 12.
When the driving force is released, the load lever 14 is biased by the spring 18 toward the bent portion 12C of the elongated hole 12.

As a result, the rotational driving force from the electric motor 4 is transmitted to the valve shaft 2 of the throttle valve 3 and the cam lever 11 via the reduction gear mechanism 5, and between the valve closing position and the fully open position of the throttle valve 3. The cam lever 11 can be rotated, and the load lever 1 is pressed against the urging force of the spring 18.
4 is rotated along the long hole 12 of the cam lever 11, and the biasing force of the spring 18 is used as a reaction force at the time of rotation.
It can continue to be assigned to 1.

Then, when the engine is stopped (the electric motor 4
When the driving force of the electric motor 4 has expired due to failure of the electric motor 4 or when the electric motor 4 has failed, the single spring 18 urges the roller 17 of the load lever 14 toward the bent portion 12C of the cam lever 11. By doing so, the cam lever 11 can be forcibly rotated via the load lever 14, and the rotation of the cam lever 11 can be stopped at a position where the roller 17 of the load lever 14 contacts the bent portion 12C of the cam lever 11. In this state, the throttle valve 3 can be automatically returned to the intermediate opening position shown in FIG.

As a result, even when the vehicle is left for a long time with the engine stopped in a cold region or the like,
By keeping the throttle valve 3 at the intermediate opening position, it is possible to prevent the throttle valve 3 from freezing, to improve the low temperature startability of the engine, and to improve the reliability and the like. Further, even when the electric motor 4 fails, the throttle valve 3 can be maintained at the intermediate opening position, so that a minimum amount of intake air can be continuously supplied to the engine. You can continue running.

Therefore, according to the present embodiment, the throttle valve 3 can be maintained at the intermediate opening position by using the single spring 18 when the power supply of the electric motor 4 is stopped or at the time of failure. The number of points can be reduced to improve the workability at the time of assembling, and the entire throttle valve device can be downsized and formed compact, and the adjustment of the opening of the throttle valve 3 can be stabilized.

Since the cam lever 11 is detachably provided at one end of the valve shaft 2 via the nut 7 or the like, a plurality of cam levers 11 having different cam shapes of the elongated holes 12 can be prepared in advance. For example, the opening of the throttle valve 3 at the intermediate opening position can be appropriately changed only by replacing the cam lever 11, and it is possible to easily cope with a change in engine specifications, a change in vehicle type, and the like.

Further, a function as a stopper for defining the maximum opening and the minimum opening of the throttle valve 3 can be provided by the long hole 12 of the cam lever 11, and it is not necessary to separately provide a special stopper or the like. When the throttle valve 3 is in the closed position, the bent claw portion 11B integrally formed with the cam lever 11 is brought into contact with the eye bolt 22 of the stopper 20, so that the valve opening at the time of closing the valve can be variably adjusted. It is also possible to adjust the rotation speed by the amount of protrusion of the eyebolt 22.

Next, FIGS. 13 to 17 show the second embodiment of the present invention.
In the present embodiment, the same reference numerals are given to the same components as those in the above-described first embodiment, and the description thereof will be omitted. However, the feature of the present embodiment lies in that the cam lever 41 is formed with the elongated hole 42 forming the cam surface and the driven gear 43 is integrally provided.

Here, the cam lever 41 has substantially the same configuration as the cam lever 11 described in the first embodiment.
As shown in FIG. 16 and FIG. 17, it has a fitting hole 41A and a bent claw portion 41B. The long hole 42 also includes a long hole 42A, a short hole 42B, a bent portion 42C, and a front edge 42D, similarly to the long hole 12 described in the first embodiment.

However, the cam lever 4 according to the present embodiment
A driven gear 43 is integrated with the driven gear 43 at a position radially separated from the fitting hole 41A, for example, by means such as welding. The driven gear 43 is formed entirely of a hard metal material into a bow shape, and is fixed to the outer peripheral side of the cam lever 41 in a fitted state.

That is, the driven gear 43 is formed of a bow-shaped gear member having the fitting hole 41A of the cam lever 41 as the center of rotation O, and is provided on the outer peripheral side of the cam lever 41 so as to be circumferentially separated from the elongated hole 42. ing. The driven gear 43 constitutes the reduction gear mechanism 5 together with the driving gear 6 and the intermediate gear 9 in the same manner as the driven gear 8 described in the first embodiment, and as shown in FIGS. Small diameter gear part 9B
Is engaged.

Thus, also in this embodiment constructed as described above, the cam lever 41 and the load lever 14 can be rotated against the spring 18 at the closed position of the throttle valve 3 as shown in FIG. In the open position of the valve 3, the cam lever 41 and the load lever 14 can rotate against the spring 18 as shown in FIG.

When the throttle valve 3 is held at the intermediate opening position, the cam lever 41 can be automatically rotated via the load lever 14 to the position shown in FIG. Almost the same effects as those of the embodiment can be obtained.

Further, according to the present embodiment, since the driven gear 43 is integrally provided on the outer peripheral side of the cam lever 41, the cam lever 41 and the driven gear 43 can be handled as a single component. The number of parts can be reduced, and workability during assembly can be improved.

In each of the above-described embodiments, the spring 18 as the urging means is connected to the hook 14 of the load lever 14.
A is described as being constituted by a tension spring disposed between A and the latching projection 19 on the throttle body 1 side.
The present invention is not limited to this.
It may be configured by a spring or the like that applies a rotational force in the direction, or may be configured to use a biasing unit such as a compression spring.

In each of the above embodiments, the valve shaft 2 of the throttle valve 3 is rotated by the electric motor 4. However, the present invention is not limited to this. Thus, a rotational force may be applied to the valve shaft 2 via the reduction gear mechanism 5.

Further, a mechanical drive means for transmitting the operation force from the accelerator pedal to the drive gear 6 as a rotational force via a wire or the like may be employed. In this case, the throttle valve 3 can be held at the intermediate opening position by the urging force of the spring 18 even when the operation of the accelerator pedal is released, or when the wire is broken at an intermediate position.

Further, in the above embodiment, the cam lever 11 (41) is connected to the driven gear 8 (4
Although described as being provided on the 3) side, the present invention is not limited to this, and a cam lever may be provided on, for example, an intermediate gear of a reduction gear mechanism.

[0080]

As described above in detail, according to the first aspect of the present invention, the cam lever provided on the reduction gear mechanism allows the throttle valve to rotate between the fully closed position and the fully open position. The throttle body is provided with a bent portion in the middle thereof, and the throttle body is provided with a cam follower that rotates in contact with the cam surface of the cam lever and a biasing means, so that the throttle body is driven with respect to the reduction gear mechanism. When the driving force of the means is released, the biasing means biases the cam follower to the bent portion side of the cam surface to open the throttle valve via the cam lever between the fully closed position and the fully open position. Since the configuration is such that the throttle valve is held at the opening position, the throttle valve can be urged to the intermediate opening position by using a single urging means, so that the number of parts can be reduced and workability during assembly can be improved.

Further, since the cam lever is provided in the reduction gear mechanism, the throttle valve device can be downsized, and the entire device can be made compact. Further, since the throttle valve can be biased to the intermediate opening position by a single biasing means, a load acting as a reaction force on the drive means when the throttle valve is driven in the valve opening direction and when the throttle valve is driven in the valve closing direction. Variations in torque and the like can be suppressed, and the adjustment of the opening of the throttle valve can be stabilized.

According to the second aspect of the present invention, since the driven gear of the reduction gear mechanism is provided integrally with the end of the valve shaft together with the cam lever, the driven gear is rotated by the driving force from the driving gear. When the throttle valve is turned, the valve shaft of the throttle valve and the cam lever can be integrally rotated, and the rotation of the cam lever can be allowed between the fully closed position and the fully opened position of the throttle valve. Since the driving force from the driving means can be reduced and transmitted to the valve shaft and the cam lever, the urging force of the urging means can be prevented from acting as an excessive reaction force on the driving means side, and the driving means can be prevented. , The driving torque can be reduced to save energy.

Further, according to the third aspect of the present invention, the cam lever is provided with a fitting hole fitted into the end of the valve shaft in a detented state.
Since the cam surface of the cam lever is formed by a long hole which is radially separated from the fitting hole and has a V-shaped bent portion in the middle thereof, the cam follower is rotated along the long hole of the cam lever. When the driving force of the driving means is released, the cam follower is engaged with the V-shaped bent portion by the urging force of the urging means, so that the rotation of the cam lever can be stopped, and the throttle valve can be moved to the middle position. It can be reliably held at the opening position.

According to the fourth aspect of the invention, the long hole of the cam lever is separated from the fitting hole in the radial direction by an arc-shaped long hole and a short hole connected to the long hole via a bent portion. The short hole and the long hole are configured such that a distance from the fitting hole becomes maximum at the position of the bent portion, and the distance from the bent portion approaches the fitting hole as the distance from the bent portion increases. Therefore, for example, when the throttle valve is turned from the intermediate opening position to the fully opened position, the cam follower can be turned along the long hole of the cam lever, and the urging force of the urging means is accordingly adjusted. It can be increased gradually. Conversely, when the throttle valve is turned from the intermediate opening position to the fully closed position, the cam follower can be turned along the short hole of the cam lever, and the urging force of the urging means is gradually increased accordingly. Can be increased. When the driving force of the driving means is released, the cam follower can be biased by the urging means toward the bent portion of the cam lever to forcibly rotate the cam lever. It can be stopped at the opening position.

According to the fifth aspect of the present invention, the cam lever and the driven gear are formed as separate members, and a fitting hole is provided at the center of rotation of the driven gear so as to be fitted into the end of the valve shaft in a detented state. With this configuration, the cam lever and the driven gear can be fixed to the end of the valve shaft through the respective fitting holes.For example, when replacing the cam lever with one having a different cam shape, the driven gear is connected from the end of the valve shaft. There is no need to remove the cam lever, and the cam lever can be easily replaced.

On the other hand, according to the sixth aspect of the present invention, since the cam lever is provided with the elongated hole and the driven gear integrally at positions spaced apart in the circumferential direction, the cam lever and the driven gear can be formed as a single part. Thereby, the number of parts can be reduced and the workability at the time of assembly can be improved.

Further, in the invention of claim 7, the driving means is constituted by an electric motor provided in the throttle body, and the reduction gear mechanism is provided on the driving gear fixed to the output shaft of the electric motor and the end of the valve shaft. Since the driven gear and the intermediate gear for transmitting the rotation of the drive gear to the driven gear are fixed, the rotational force of the electric motor can be reduced and transmitted from the drive gear to the intermediate gear, and the rotation of the intermediate gear is driven by the driven gear. It can be transmitted to gears at reduced speed. As a result, the electric motor can be configured by a small motor having a small output torque, and the reduction gear mechanism can be formed compact, and the entire throttle valve device can be downsized.
The weight can be reduced.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a throttle valve device according to a first embodiment of the present invention.

FIG. 2 is an enlarged front view showing a reduction gear mechanism and the like of the throttle valve device in a state where a cover of a gear case is removed, as viewed from the direction of arrows II-II in FIG. 1;

FIG. 3 is a front view showing a cam lever and the like in a state where a throttle valve is turned to a closed position.

FIG. 4 is a front view showing a cam lever and the like in a state where a throttle valve is turned to a fully open position.

FIG. 5 is an enlarged sectional view showing a throttle valve at an intermediate opening position.

FIG. 6 is a sectional view similar to FIG. 5, showing the throttle valve in a closed position;

FIG. 7 is a sectional view similar to FIG. 5, showing the throttle valve in a fully open position.

FIG. 8 is an enlarged cross-sectional view showing a load lever and the like as viewed from a direction indicated by arrows VIII-VIII in FIG. 2;

FIG. 9 is an enlarged front view showing a cam lever.

FIG. 10 is a cross-sectional view showing the cam lever as viewed from the direction indicated by arrows XX in FIG. 9;

FIG. 11 is an enlarged front view showing a driven gear.

FIG. 12 is a cross-sectional view showing the driven gear as viewed from the direction indicated by arrows XII-XII in FIG. 11;

FIG. 13 is a front view of the same position as FIG. 2 showing a reduction gear mechanism and the like of a throttle valve device according to a second embodiment of the present invention.

FIG. 14 is a front view showing a cam lever and the like in a state where the throttle valve is turned to a closed position.

FIG. 15 is a front view showing a cam lever and the like in a state where the throttle valve is rotated to a fully open position.

FIG. 16 is an enlarged front view showing a cam lever in which a driven gear is integrated.

FIG. 17 shows a cam lever and is shown by arrows XVII-XVII in FIG.
It is sectional drawing seen from the direction.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Throttle body 1A Throttle chamber 1B Motor accommodation case 1C Gear case 2 Valve shaft 3 Throttle valve 4 Electric motor (drive means) 4A Output shaft 5 Reduction gear mechanism 6 Drive gear 8, 43 Follower gear 8A, 11A, 41A Fitting hole 9 Intermediate gear 9A Large-diameter gear 9B Small-diameter gear 11,41 Cam lever 11B, 41B Bend 12,12 Long hole (cam surface) 12A, 42A Long hole 12B, 42B Short hole 12C, 42C Bend 14 Load lever (cam follower) 17 Roller 18 Spring (biasing means) 20 Stopper 24 Cover 25 Accelerator operation amount detection device

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-6-137173 (JP, A) JP-A-2-308930 (JP, A) JP-A-9-222033 (JP, A) JP-A-7- 139376 (JP, A) JP-A-10-131771 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) F02D 9/02 F02D 11/00

Claims (7)

(57) [Claims] A throttle body having an intake passage formed therein; a throttle valve rotatably provided on the throttle body via a valve shaft to open and close the intake passage; and a throttle valve for driving the throttle valve. A throttle valve comprising: a drive unit provided on a throttle body; and a reduction gear mechanism provided between the drive unit and the valve shaft for reducing the drive force of the drive unit and transmitting the drive force to the valve shaft of the throttle valve. In the apparatus, a cam surface provided on the reduction gear mechanism and allowing the throttle valve to rotate between a fully-closed position and a fully-open position is provided. A cam lever serving as a bent portion for holding the cam lever at a degree position; The cam and the cam follower are constantly urged toward the cam surface of the cam lever, and when the driving force of the driving means is released, the cam follower is urged toward the bent portion of the cam surface. A biasing means for holding the throttle valve at the intermediate opening position via the cam lever. 2. The reduction gear mechanism includes: a drive gear provided on the drive means side; and a driven gear provided at an end of the valve shaft and transmitting rotation of the drive gear to the valve shaft. The throttle valve device according to claim 1, wherein the driven gear is integrated with the camshaft and the valve shaft. 3. The cam lever has a fitting hole fitted in an end portion of the valve shaft in a detented state, and the cam surface is formed on the cam lever so as to be radially separated from the fitting hole. 3. The throttle valve device according to claim 2, wherein the middle portion is constituted by a long hole having a V-shaped bent portion. 4. The elongated hole of the cam lever has an arc-shaped elongated hole portion extending radially away from the fitting hole and extending in the circumferential direction, and the bent portion formed shorter than the elongated hole portion. And a short hole connected to the long hole through the short hole and the long hole, the radial distance from the fitting hole is largest at the position of the bent portion, and the bent portion 4. It has a hole shape which approaches the fitting hole as the distance from the hole increases.
3. The throttle valve device according to claim 1. 5. The cam lever and the driven gear are formed as separate members, and a fitting hole is provided at a rotation center side of the driven gear so as to be fitted in an end portion of the valve shaft in a detented state. The throttle valve device according to claim 3. 6. The throttle valve device according to claim 3, wherein said cam lever is provided integrally with said elongated hole and a driven gear at positions spaced apart in a circumferential direction. 7. The drive means comprises an electric motor provided in a throttle body, wherein the reduction gear mechanism is fixed to an output shaft of the electric motor and to an end of the valve shaft. 6. A driven gear, and an intermediate gear provided between the driven gear and the driving gear for transmitting rotation of the driving gear to the driven gear.
Or the throttle valve device according to 6.