JP2001241336A - Throttle valve device for internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the possibility of abraded powder flying from a gear system adhering to a return spring, and to stably ensure the intake air amount controlling property of the throttle valve. SOLUTION: This throttle valve device for an internal combustion engine comprises a throttle valve 2 for controlling the mount of intake air for an engine 1, an actuator 5 for generating driving force, a gear A16 fixed on an output shaft 5a of the actuator 5, and a gear C18 fixed on a rotating shaft of the throttle valve. The throttle valve device is also provided with a gear system 7 for transmitting the driving force of the actuator 5 to a throttle shaft 6, a return spring 22 provided on the other end side of the throttle valve 6 from the gear C18 and applying urging force against rotational movement in c1 direction of the gear C18, and spring cover 23 for covering a facing side to the gear system 7 of the return spring 22, between the gear C18 and the return spring 22.

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 for an internal combustion engine having a throttle valve for controlling an intake air amount of the internal combustion engine, and more particularly to a throttle valve device for an internal combustion engine in which the throttle valve is driven by an actuator such as an electric motor. About.

[0002]

2. Description of the Related Art In recent years, for example, as a throttle valve (throttle valve) control method for an internal combustion engine for a vehicle such as an automobile, the amount of operation of an accelerator pedal has been reduced instead of the conventional direct operation of the throttle valve by operation of an accelerator pedal. A so-called electronic throttle type throttle valve device, which takes in as an electric signal by a sensor, performs predetermined arithmetic processing, supplies the electric signal to an actuator composed of an electric motor or the like, and controls opening and closing of the throttle valve by this actuator, is being applied.

Conventionally, such an electronic throttle type throttle valve device is rotatably disposed in a throttle body and controls the intake air amount of an internal combustion engine, as described in, for example, Japanese Patent Application Laid-Open No. 8-177534. A throttle valve, an actuator for generating a driving force, a first gear means provided on one end of a rotary shaft of the throttle valve and fixed to an output shaft of the actuator, and a second gear fixed to the rotary shaft of the throttle valve A gear mechanism for transmitting the driving force of the actuator to the rotary shaft of the throttle valve; and a second gear unit provided on the other end side of the rotary shaft for resisting the rotation of the second gear unit in one direction. A return spring for applying an urging force.

In the above structure, the driving force in a certain direction generated from the output shaft of the actuator is transmitted to the gear mechanism by, for example, first gear means of the output shaft of the actuator → another gear means meshing therewith → this gear. The transmission is transmitted to the second gear unit fixed to the rotary shaft of the throttle valve and is decelerated, and is transmitted to the rotary shaft of the throttle valve to open the throttle valve at a predetermined angle.

At this time, one end of the rotation shaft of the return spring is fixed to the second gear means, and the other end of the rotation shaft of the return spring is fixed to a spring mounting portion provided on the housing of the throttle body. As a result, the return spring is elastically deformed by the rotation operation of the second gear unit in one direction. When the driving force of the actuator is lost, the return spring
The urging force for returning to the original shape rotates the second gear means in the direction opposite to the one direction, whereby the throttle valve returns to the original position (valve closing).

[0006]

However, the above prior art has the following problems.

That is, as described above, the return spring is elastically deformed during the valve opening direction operation (during the rotation operation of the second gear means in one direction), and the valve closing direction operation in which the driving force of the actuator is reduced. At this time (during the rotation operation of the second gear means in the reverse direction), it elastically returns to the original state. Therefore, during the use period, the deformation and the return are repeated semipermanently.

On the other hand, as described above, when the throttle valve operates in the valve opening direction and the valve closing direction, the driving force is transmitted while the first gear means and the second gear means are engaged in the gear mechanism. , Friction when these gears mesh (rubbing)
As a result, the gears wear and generate abrasion powder. Even during operation, friction (rubbing) occurs at the meshing portions of the gears due to vibrations of the vehicle and the engine in the gear mechanism, which also generates wear powder.

Here, the return spring is provided on the other end of the rotating shaft of the second gear means, and is relatively close to the gear mechanism. Therefore, it cannot be said that there is no possibility that the abrasion powder generated in the gear mechanism will fly toward and adhere to the return spring as described above.
If the flying wear powder adheres to the surface of the return spring, the friction increases at that portion, so that it cannot be said that there is no possibility that the above-described deformation / return behavior of the return spring is adversely affected. . For example, a portion of the return spring on one end side of the rotation shaft (second portion)
The part fixed to the gear means) and the other end of the rotating shaft (the spring mounting part of the throttle body housing)
When the abrasion powder adheres, the friction between the second gear means or the housing spring mounting portion and the return spring increases. As a result, hysteresis occurs with the passage of time when the return spring is deformed and when the return spring returns to the original state. There is no possibility that there is no possibility that it will not return, or the behavior at the time of return will be different from the behavior at the time of deformation, and it will be difficult to stably maintain the controllability of the intake air amount of the throttle valve. I can not say.

[0010] An object of the present invention is to reduce the possibility that abrasion powder flying from a gear mechanism adheres to a return spring.
It is an object of the present invention to provide a throttle valve device for an internal combustion engine that can stably secure the control of the intake air amount of the throttle valve.

[0011]

(1) In order to achieve the above object, the present invention provides a throttle valve rotatably disposed in a throttle body for controlling an intake air amount of an internal combustion engine, and a driving force. An actuator to be generated, a first gear unit provided on one end side of the rotation shaft of the throttle valve and fixed to an output shaft of the actuator, and a second gear unit fixed to the rotation shaft of the throttle valve, A gear mechanism for transmitting the driving force of the actuator to the rotation shaft of the throttle valve; and a gear mechanism provided at the other end of the rotation shaft from the second gear means, for resisting a rotation operation of the second gear means in one direction. A return spring for applying a biasing force to the internal combustion engine, wherein at least the gear mechanism of the return spring is provided between the second gear means and the return spring. Providing a cover means for the dustproof covering the side faces.

When the throttle valve operates in the valve opening direction and the valve closing direction,
In the gear mechanism, the driving force is transmitted while the first gear means, the second gear means, and the like mesh with each other. At this time, the gears usually wear due to friction (rubbing) when the gears mesh with each other, and wear powder is generated. Even during operation, friction (rubbing) occurs at the meshing portions of the gears due to vibrations of the vehicle and the engine in the gear mechanism, which also generates wear powder.

On the other hand, the return spring is elastically deformed when the actuator is driven in the valve opening direction (during the rotation of the second gear means in one direction), and is elastically deformed during the valve closing direction operation of the actuator (the second gear means). (During the rotation operation in the opposite direction), elastically returns to the original state. Therefore,
During the period of use, this deformation and return will be repeated semi-permanently. The return spring is provided on the other end of the rotation shaft of the second gear means, and is relatively close to the gear mechanism. Therefore, it cannot be said that there is no possibility that the abrasion powder generated in the gear mechanism will fly toward and adhere to the return spring as described above.

Therefore, in the present invention, a dustproof cover means is provided so as to cover at least the side of the return spring facing the gear mechanism. Thus, the possibility that wear powder flying from the gear mechanism side adheres to the return spring can be reduced. Therefore, unlike the conventional structure, it is possible to reduce the possibility that the flying wear powder adheres to the surface of the return spring and increase the friction, and suppress the occurrence of hysteresis in the deformation and return of the return spring. As a result, it is possible to stably secure the intake air amount controllability of the throttle valve.

(2) In the above (1), preferably,
A gear case provided on one end side of the rotary shaft of the throttle body to cover the gear mechanism; and at least one of a portion of the housing of the throttle body near the first gear unit and a portion of the gear case near the first gear unit. And the cover means is provided so as to cover the side of the return spring facing the drain hole.

In general, in this type of throttle valve device for an internal combustion engine, the throttle valve and the rotary shaft of the internal combustion engine and the actuator are housed in a housing of the throttle body, and one end of the rotary shaft of the throttle body housing is formed as an opening. In some cases, the gear mechanism including the first and second gear means is exposed outside the throttle body, and a separate gear case is attached so as to cover the opening, and the gear mechanism is housed inside. Here, in such a throttle valve device for an internal combustion engine, water may accumulate near the first gear means provided on one end side of the rotary shaft of the actuator. Therefore, in the throttle valve device provided with the gear case as described above, the drain hole for draining the water is provided in the portion of the throttle body housing near the first gear means or in the first portion of the gear case.
It is often provided near the gear means. Since this drain hole is an opening communicating between the throttle body housing / gear case internal space and the outside, it cannot be said that there is no possibility that dust from the outside will enter the internal space from these drain holes. In this case, it cannot be said that there is no possibility that the intruding dust flies toward and adheres to the return spring, and has an unfavorable effect similar to the wear powder of the above (1).

Therefore, in the present invention, cover means for covering the side of the return spring facing the gear mechanism is provided so as to further cover the side of the return spring facing the drain hole. Thus, the possibility that dust coming from the outside via the drain hole adheres to the return spring can also be reduced, so that the controllability of the intake air amount of the throttle valve can be reliably ensured stably. .

(3) In the above (1) or (2), preferably, one end side of the rotation shaft of the return spring is fixed to the second gear means, and the rotation shaft of the return spring and the like are provided. An end side is fixed to a spring mounting portion provided on a housing of the throttle body. An outer peripheral side of a portion of the spring mounting portion located on a radially inner peripheral side of the return spring is connected to one end of the rotating shaft. The diameter is reduced toward the side. The return spring at the other end of the rotary shaft from the second gear means applies an urging force against the rotation of the second gear means in one direction. , And the other end of the rotation shaft of the return spring may be fixed to the spring mounting portion of the throttle body housing. On the other hand, (1)
As described above, the return spring is elastically deformed at the time of operation in the valve opening direction (at the time of rotation operation in one direction of the second gear means). At this time, the return spring is deformed so that its radial center is eccentric. In order to cope with such deformation, when the above-mentioned spring mounting portion is provided, usually, a part of the spring mounting portion is provided on the radially inner peripheral side of the return spring, and the return spring is eccentric when deformed. The part shifted toward the inner peripheral side is guided on the outer peripheral side of the part provided on the inner peripheral side.

Here, in the present invention, the outer peripheral side (that is, the side that comes into contact with the return spring) of the portion of the spring mounting portion that performs the guiding function as described above that is located on the radially inner peripheral side of the return spring. The diameter of the throttle valve is reduced toward the one end of the rotary shaft. Accordingly, by appropriately setting the reduced diameter shape (for example, by setting by adjusting the taper angle), even when the return spring is eccentric during the deformation and is shifted to the inner peripheral side, the throttle valve of the return spring is rotated. Only a limited part (for example, the first row) of the other end of the shaft can be brought into contact with the outer peripheral side of the spring attachment part. Therefore,
Since the contact area between the return spring and the spring mounting portion can be minimized, even if the wear powder described in the above (1) or the dust described in the above (2) adheres to the return spring, the friction is reduced. Increase and increase in wear of the return spring itself can be minimized. As a result, it is possible to more reliably suppress the occurrence of hysteresis in the deformation and return of the return spring, and it is possible to more reliably and stably secure the intake air amount controllability of the throttle valve.

(4) In the above (1) or (2), preferably, one end of the rotation shaft of the return spring is fixed to the second gear means, and the rotation shaft of the return spring and the like are fixed. An end side is fixed to a spring mounting portion provided on a housing of the throttle body, and the cover means is located on an outer peripheral side in a radial direction of the return spring and guides a deformation operation of the return spring. , And the outer guide portion has an enlarged diameter toward the other end of the rotating shaft. One end of the rotation shaft of the return spring is fixed to the second gear means as a configuration in which a return spring on the other end side of the rotation shaft from the second gear means applies an urging force against the rotation operation of the second gear means in one direction. In some cases, the other end of the rotation shaft of the return spring is fixed to the spring mounting portion of the throttle body housing. On the other hand, as described in the above (1), the return spring is elastically deformed during the valve opening direction operation (when the second gear means rotates in one direction), and the radial center thereof is eccentric at this time. Deform to do. In order to cope with such deformation, in the present invention, the cover means is provided with an outer guide portion located on the radially outer peripheral side of the return spring to guide the deformation operation of the return spring, and the return spring is eccentric when deformed. The part shifted to the outer peripheral side is guided by the inner peripheral side of the outer guide part.

Further, in the present invention, the outer guide portion which performs the guide function as described above is formed to have a diameter increasing toward one end of the throttle valve rotating shaft. Accordingly, by appropriately setting the enlarged shape (for example, by adjusting the taper angle), even when the return spring is eccentric during deformation and is shifted to the outer peripheral side, the throttle valve rotating shaft of the return spring is used. Only a limited portion (for example, the first row) on one end side can be brought into contact with the inner peripheral side of the outer guide portion. Therefore, since the contact area between the return spring and the outer guide portion can be minimized, even if the wear powder described in the above (1) or the dust described in the above (2) adheres to the return spring. In addition, the increase in friction and the promotion of wear of the return spring itself can be minimized. As a result, it is possible to more reliably suppress the occurrence of hysteresis in the deformation and return of the return spring, and it is possible to more reliably and stably secure the intake air amount controllability of the throttle valve.

(5) In the above (1) or (2), preferably, one end of the rotation shaft of the return spring is fixed to the second gear means, and the rotation shaft of the return spring and the like are provided. An end side is fixed to a spring mounting portion provided on a housing of the throttle body, and the cover means is located on a radially inner peripheral side of the return spring and guides an inner guide for deforming the return spring. And a length of the inner guide portion in the rotation axis direction is a length corresponding to only a part of the entire length of the return spring in the rotation axis direction. One end of the rotation shaft of the return spring is fixed to the second gear means as a configuration in which a return spring on the other end side of the rotation shaft from the second gear means applies an urging force against the rotation operation of the second gear means in one direction. And
In some cases, the other end of the rotation shaft of the return spring is fixed to the spring mounting portion of the throttle body housing. On the other hand, as described in the above (1), the return spring is elastically deformed during the valve opening direction operation (when the second gear means rotates in one direction), and the radial center thereof is eccentric at this time. Deform to do. In order to cope with such deformation, in the present invention, the cover means is provided with an inner guide portion which is located on the radially inner peripheral side of the return spring and guides the deformation operation of the return spring. Then, the portion that shifts toward the inner peripheral side is guided by the outer peripheral side of the inner guide portion.

Further, in the present invention, the length of the inner guide portion which performs the guiding function as described above in the direction of the rotation axis of the throttle valve is set to a length corresponding to only a part of the entire length of the return spring in the direction of the rotation axis of the throttle valve. And Accordingly, even when the return spring is eccentric during deformation and shifts toward the inner peripheral side, for example, only a limited portion (for example, the first row) of the return spring at one end side of the throttle valve rotating shaft is located on the outer peripheral side of the inner guide portion. Can be brought into contact with. Therefore, since the contact area between the return spring and the inner guide portion can be minimized, even if the wear powder described in the above (1) or the dust described in the above (2) adheres to the return spring. In addition, the increase in friction and the promotion of wear of the return spring itself can be minimized. This makes it possible to more reliably suppress the occurrence of hysteresis in the deformation and return of the return spring.
The controllability of the intake air amount of the throttle valve can be more reliably and stably secured.

(6) In any one of the above (1) to (5), preferably, the second gear means and the cover means are integrally formed as one member.

When the second gear means and the cover means are configured as separate members, the procedure for assembling the second gear means, the cover means, the return spring, and the rotary shaft of the throttle valve to the throttle body is as follows. Become. That is, the rotation axis of the throttle valve is assembled to the throttle body →
Fix the other end of the return spring shaft of the return spring to the throttle body side (for example, a spring mounting portion provided on the housing) → assemble the cover means and the second gear means to the throttle valve rotation shaft → rotate the return spring of the throttle valve The procedure is such that one end of the shaft is fixed to the second gear means. The procedure is like this, after the procedure →
This is because, in the reverse order, the second gear means and the cover means, which are separate members, can freely rotate with respect to each other, and it is not easy to collectively attach them to the rotary shaft of the throttle valve.

However, as described above →→→
When the assembling work is performed by the following procedure, since the cover means and the second gear means are fixed to the throttle valve rotating shaft in the procedure, the end of the return spring one end side of the return spring is fixed to the second gear means in the procedure. In doing so, the operation is performed while receiving the urging force of the return spring. At this time, since the cover means is provided between the second gear means and the return spring, an end of the return spring on one end side of the throttle valve rotating shaft is actually cut out, for example, in a part of the cover means. And the like and appear on the second gear means side. Therefore, the work in the above procedure is, in fact, the end of the return spring one end side of the throttle valve rotation shaft,
After being pulled out with a jig through the notch or the like of the cover means, the work is fixed to the second gear means, which is a complicated work, and it is difficult to improve workability. In addition, the size of the notch or the like of the cover means must be set relatively large for convenience in the pulling-out operation as described above, and the original function of preventing abrasion dust and dust from coming down is reduced accordingly. There is.

Therefore, in the present invention, the second gear means and the cover means are integrally formed as one member.
As a result, the second gear means and the cover means do not rotate freely with each other, so that the rotation shaft of the throttle valve is assembled to the throttle body. → The end of the return spring on one end side of the throttle valve rotation shaft of the return spring is used as the second gear means. Fixing → Fixing the other end of the return spring on the rotary shaft side of the return spring to the throttle body side (for example, a spring mounting portion provided on the housing) → Cover means and second gear means (in this case, these two members are one member). ) Is assembled to the throttle valve rotation shaft, and the work can be easily performed in this order (
The order can be reversed or almost simultaneous.) Therefore, the complicated work as in the above-described work sequence of →→→ can be eliminated, the workability can be improved, and the productivity can be improved.
Also, before the cover means and the second gear means are attached to the throttle valve rotating shaft in the procedure, the return spring can be passed through the notch or the like by the return spring attaching work in the procedure in advance. It is not necessary to consider the convenience of the above, and the size of the notch or the like can be minimized. Therefore, there is also an effect that a decrease in the action of preventing wear dust and dust from flying can be minimized.

[0028]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 2 is a system conceptual diagram of the throttle valve device according to the present embodiment and a control system related thereto.

In the system shown in FIG. 2, an engine 1, a throttle valve device 3 of this embodiment having a throttle valve 2 for controlling the intake air amount of the engine, and an electronic throttle control module (ETM) 4 are provided. Is provided.

The throttle valve device 3 includes the throttle valve 2, an actuator (for example, an electric motor) 5 for generating a driving force,
It has a gear mechanism (reduction mechanism) 7 for amplifying the driving force of the actuator 5 and transmitting it to the throttle shaft 6 of the throttle valve 2, and a throttle position sensor (TPS) 8 for converting the rotation amount of the throttle valve 2 into an electric signal. are doing.

In the above configuration, the electronic throttle control module 4 outputs a drive control signal to the actuator 5, and the actuator 5 is driven according to the drive control signal. The driving force of the actuator 5 is transmitted to the throttle shaft 6 of the throttle valve 2 while being decelerated via the gear mechanism 7, and the throttle valve 2 is opened at a predetermined opening. At this time, the opening degree of the throttle valve 2 is detected by the throttle position sensor 8, output as a sensor signal corresponding to the rotation amount, and fed back to the electronic throttle control module 4. This system is a so-called DBW electronic throttle system in which the electronic throttle control module 4 performs feedback control of the opening of the throttle valve 2 as described above. FIG.
1 is a vertical cross-sectional view (corresponding to a cross-sectional view taken along a II line in FIG. 3 described later) showing the entire structure of the throttle valve device 3 according to the present embodiment shown in FIG. 2, and FIG. FIG. 4 is an arrow side view of a structure in which a gear case (described later) is removed from the structure when viewed from a direction A in FIG. 1. FIG. is there.

In the throttle valve device 3 according to the present embodiment shown in FIGS. 1, 3 and 4, the throttle valve 2 and the actuator 5 are contained in a housing 10 of a throttle body 9. That is, as particularly shown in FIG. 1, the throttle valve 2 is located above the space in the throttle body 9.
The actuator 5 is arranged at the lower part. At this time,
Throttle shaft 6 of throttle body housing 10
One end side (the right side in FIG. 1) is an opening, and as a result, the gear mechanism 7 is exposed outside the throttle body 9, but is internally formed by a gear case 11 separately attached so as to cover the opening. It is stored in.

A drain hole 12 is provided in a lower portion of the throttle body housing 10 near the actuator 5 (specifically, a portion near a gear (A) 16 described later attached to the output shaft 5a). I have. This is for discharging moisture that can enter through a lead wire lead-out portion 13 for the actuator 5 provided at a lower portion of the housing 10 and a gap between the gear case 11 and the housing 10.
The drain hole 12 may be provided not in the lower part of the housing 10 but in a portion of the gear case 11 near the actuator 5.

The throttle body 9 also serves to fix the entire throttle valve device 3 to the vehicle body.

The throttle shaft 6 is rotatably supported (supported) via a ball bearing 14 provided on a throttle shaft support 10a of the throttle body housing 10.
A lever 15 as a link mechanism is fixed to the side of the throttle shaft 6 opposite to the gear mechanism 7 (left side in FIG. 1), and is connected to the throttle position sensor 8 via the lever 15. Thus, the rotation operation of the throttle shaft 6 is transmitted to the throttle position sensor 8 via the lever 15, and the rotation angle (the amount of rotation) can be detected by the throttle position sensor 8.

The gear mechanism 7 is provided at one end (right end in FIG. 1) of the throttle shaft 6 and has three gears, ie, a gear (A) fixed (for example, integrally) to the output shaft 5a of the actuator 5. ) 16 and a gear (B) that meshes with the gear (A) 16 to reduce the drive of the actuator 5.
17 and a spring (described later) together with a spring cover 23 are fixed to the throttle shaft 6 via bolts 6a.
And a gear (C) 18 that meshes with the gear.

The gear (B) 17 is rotatably supported (supported) through a flat bearing 20 on a round bar-shaped shaft 19 inserted and fixed in the throttle body housing 10. The gear (C) 18 has a first end face 18a and a second end face 18a.
b, and a notch 18c for attaching a return spring 22 described later.

The output shaft 5a of the actuator 5 rotates in one direction, and through the gear (A) 16 and the gear 17 (B),
When the gear (C) 18 rotates in the direction of arrow c1 and the second end face 18b engages with the adjuster 21 fixed to the throttle body housing 10, the gear (C) is thereby rotated.
The rotation of arrow 18 in the direction of arrow c1 (corresponding to the rotation of gear (A) in the direction of arrow a1 and the rotation of gear (B) in the direction of arrow b1) is restricted.

The output shaft 5a of the actuator 5 rotates in the other direction, and the gear (C) 18 rotates in the direction c2 via the gear (A) 16 and the gear 17 (B), and the first end face is rotated. 1
When the gear 8a engages with the projection 10b provided on the throttle body housing 10, the gear (C) 18
In the direction c2 (corresponding to the rotation of the gear (A) 16 in the direction of the arrow a2 and the rotation of the gear (B) 17 in the direction of b2)
Is restricted. FIG. 1 shows a first end face 1
8a is engaged with the projection 10b, and the gear (C) 18 is indicated by an arrow c.
It shows a state in which it is restricted so as not to rotate any more in two directions.

The throttle shaft 6 of the gear (C) 18
On the other end side (the left side in FIG. 1), a return spring 22 having a predetermined set load (spring force) is provided. One end side (one hook portion) 22a (see FIGS. 3 and 4) of the return spring 22 is fixed (hook) to the cutout portion 18c of the gear (C) 18 described above, and the return spring 22 The other end (the other hook portion) 22b (see FIGS. 1 and 4) is fixed (hooked) to a cutout portion (not shown) of a spring attachment portion 10A provided in the throttle body housing 10. With such a structure, the return spring 22 resists the rotation of the gear (C) 18 in the direction of the arrow c1 between the housing 10 and the gear (C) 18 (in other words, in the direction in which the throttle valve 2 returns). ) The urging force is given as a drag, so that when the actuator 5 is not operated, the throttle shaft 6 can be returned to a predetermined rotational direction position (Idle position).

In the throttle valve device 3 having the basic configuration as described above, the output shaft 5a of the actuator 5 is driven in one direction (or another direction, the same applies hereinafter) to the gear (A) 1.
When the gear 6 rotates in the direction of the arrow a1 (or the direction of a2), the gear (B) 17 rotates in the direction of the arrow b1 (or the direction of b2).
This rotational driving force is transmitted to a gear (C) 18 fixed to the throttle shaft 6, the gear (C) 18 and the throttle shaft 6 rotate in the direction of the arrow c1 (or c2), and the throttle valve 2 is moved. It rotates in the opening direction (or closing direction). The rotation angle (rotation amount) at this time is determined by the lever 15 connected to the throttle valve 2.
, And is detected by the throttle position sensor 8.

The most significant feature of the throttle valve device 3 of the present embodiment having the above basic configuration and operation is that the gear (C) 18
A structure for covering the return spring 22 with a dustproof spring cover (spring holder) 23 provided between the spring cover and the return spring 22, a contact structure between the outer guide portion and the inner guide portion of the spring cover, and a contact structure for the housing spring mounting portion. It is a contact structure. Hereinafter, the detailed structure will be described.

(A) Structural Features of the Throttle Valve Device 3 (A-1) Cover Structure of the Return Spring with a Spring Cover The spring cover 23 is located on the radially outer peripheral side of the return spring 22 and performs the deformation operation of the return spring 22. An outer guide portion 23a for guiding, and a return spring 22 located radially inward of the return spring 22;
And an inner guide portion 23b that guides the deformation operation of.

The spring cover 23 is fixed to one end (the right end in FIG. 1) of the throttle shaft 6 together with the gear (C) 18 via the seal ring 6b by the bolt 6a as described above. At this time, the gear (C) 18
An oval-shaped hole 18A formed at the radial center and an oval-shaped hole 23A formed at the radial center of the spring cover 23 are provided at one end (the right end in FIG. 1) of the throttle shaft 6. To the shaft 6A of the oval shape
The throttle shaft 6 rotates in accordance with the rotation direction.

The spring cover 23 covers the one end side (the right side in FIG. 1) of the throttle shaft 6 of the return spring 22, as shown in FIGS. , Return spring 2
The side facing the gear mechanism 7 and the side facing the drain hole 12 are covered.

(A-2) Abutment Structure of Outer Guide / Inner Guide Here, the above-described return spring 22 is driven by the actuator 5 in one direction to output the gear (A) 1.
6. Eccentrically receiving the torsional force in the direction d1 (corresponding to the directions a1, b1, and c1 in FIG. 3 in FIG. 3) via the gear (B) 17 and the gear (C) 18. In addition, there are portions that are shifted from the original center axis to the radially inner circumferential side, portions that are shifted to the radially outer circumferential side, and the like. Therefore, the outer guide portion 23a and the inner guide portion 23b of the spring cover come into contact with the outer peripheral side or the inner peripheral side of the return spring 22 together with the later-described spring mounting portion 10A when such displacement occurs. It functions to guide its deformation behavior and limit eccentricity.

At this time, the outer guide portion 23a has a diameter increasing toward the other end of the throttle shaft 6 (left side in FIG. 1, lower side in FIG. 4) (in this example, a tapered shape, but a stepped shape, etc.). Therefore, only the first row from the one end side 22a of the return spring has the outer guide portion 23a.
Are designed to abut against the inner peripheral portion. However, the minimum inner diameter of the outer guide portion 23a is slightly larger than the maximum value of the outer diameter of the return spring 22 in the movable range of the gear (A) 16, the gear (B) 17, and the gear (C) 18, and the eccentric direction. Other than that, there is no contact with the return spring 22.

The length of the inner guide portion 23b in the axial direction (guide height) corresponds to a part of the entire length of the return spring 22 in the direction of the throttle shaft 6 (in this example, the length of the return spring 22). (Less than the pitch), so that only the first row from one end side 22a of the return spring 22 can be brought into contact with the outer peripheral portion of the inner guide portion 22b. However, the maximum outer diameter of the inner guide portion 23b is the return spring 22 in the movable range of the gear (A) 16, the gear (B) 17, and the gear (C) 18.
The value is slightly smaller than the minimum value of the inner diameter, and the inner peripheral side of the return spring 22 is guided only when the diameter of the return spring 22 is reduced, so that the amount of eccentricity of the return spring 22 is reduced.

(A-3) Contact Structure of Spring Attachment As a further feature of this embodiment, there is the shape of the spring attachment 10A described above. Spring mounting part 10A
Are the spring cover 23 and the return spring 22 of the throttle body housing 10 as described above.
And the other end 22b of the return spring 22 is attached.

As shown in FIG. 1, the outer peripheral side 10Aa of the portion of the spring mounting portion 10A located on the radially inner peripheral side of the return spring 22 faces one end of the throttle shaft 6 (the right side in FIG. 1). It has a reduced diameter shape (in this example, a tapered shape, but a stepped shape or the like may be used), so that when the return spring 22 is deformed and eccentric as described above, only the first row from the other end side 22b is moved. It is designed to contact the outer peripheral side 10Aa.

The other end of the throttle shaft 6 of the return spring 22 is inserted and arranged in a spring insertion portion 10B which is a substantially annular concave portion located on the outer peripheral side of the spring mounting portion 10A. A spring insertion outer wall portion 10C is provided on the outer peripheral side of the spring insertion portion 10B. Then, the outer guide portion 2 of the spring cover 23
3a and the radial interval between the spring insertion outer wall portion 10C are
The minimum is provided as long as the outer guide portion 23a, the return spring 22, and the spring insertion outer wall portion 10C do not contact each other.

In the above, the throttle shaft 6 constitutes the rotating shaft described in the claims, the gear (A) 16 constitutes first gear means fixed to the output shaft of the actuator, and the gear (C) ) 18 constitutes second gear means fixed to the rotary shaft of the throttle valve. Also, the spring cover 23
Is provided between the second gear means and the return spring, and constitutes dust-proof cover means for covering at least the side of the return spring facing the gear mechanism.

(B) Operation and Effect of Main Portion of Throttle Valve Device 3 The operation and effect of the main portion of the throttle valve device 3 of the present embodiment configured as described above will be described below. (B-1) Dust proofing by a spring cover (wear particles such as gears) When the throttle valve 2 is operated in the valve opening direction and the valve closing direction, the gear (A) 16 and the gear (B) in the gear mechanism 7 as described above. And 17, the driving force is transmitted while the gear (C) 18 meshes. At this time, the gears usually wear due to friction (rubbing) when the gears mesh with each other, and wear powder is generated. Also, even when not operating, the gears 16 through in the gear mechanism 7 due to the vibration of the vehicle and the engine 1.
Friction (rubbing) occurs at the meshing portion 18, which also generates wear powder.

On the other hand, the return spring 22 is elastically deformed when the actuator 5 is driven in the valve opening direction (when the gear (C) 18 rotates in the direction of the arrow c1), and when the valve closing direction is operated (gear ( C) At the time of the rotation operation in the direction of arrow c2 of 18), it returns elastically to the original state. Therefore, during the use period, the deformation and the return are repeated semipermanently. Since the return spring 22 is provided on the other end side of the throttle shaft 6 of the gear (C) 18, the return spring 22 is relatively close to the gear mechanism 7 as shown in FIG. 1. Therefore, as it is, it cannot be said that there is no possibility that the abrasion powder generated in the gear mechanism 7 will fly toward the return spring 22 and adhere as described above.

Therefore, in the present embodiment, a dust-proof spring cover 23 is provided to cover at least the side of the return spring 22 facing the gear mechanism 7. Thus, the possibility that wear powder flying from the gear mechanism 7 adheres to the return spring 22 can be reduced. Therefore, unlike the conventional structure, it is possible to reduce the possibility that the flying wear powder adheres to the surface of the return spring 22 and increase the friction, and suppress the occurrence of hysteresis in the deformation and return of the return spring 22. This allows
The controllability of the intake air amount of the throttle valve 2 can be secured stably.

In addition, for example, the gear (C) 1
8 and the throttle body housing 1
Rubbing with the projection 10b of No. 0, gear (B) 17, shaft 1
9 and rubbing of the flat bearing 14, rubbing of the flat bearing 14 and the throttle shaft supporting portion 10 a which is a bearing holding portion, bracket portions 5 b of the actuator 5 (see FIG. 1), and corresponding bracket receivers of the throttle body casing 10. Needless to say, the present invention is also effective against flying dust generated by rubbing with the portion 10c and other flying dust generated in the gear box 11 in the same space as the return spring 22. (B-2) Dust prevention by spring cover (dust from drain hole) Drain hole 12 provided at the lower part of throttle body housing 10 has an opening for communicating the internal space of throttle body housing 10 / gear case 11 with the outside. Therefore, it cannot be said that there is no possibility that dust from the outside will enter the internal space through the drain hole 12. In this case, the dust that has entered will fly toward the return spring 22 and adhere to the (B). It cannot be said that there is no possibility of giving the same unfavorable influence as the wear powder of -1).

Therefore, in this embodiment, the spring cover 23 is connected to the drain hole 1 of the return spring 22.
It is provided so as to cover the side facing 2. Thus, the possibility that dust coming from the outside via the drain hole 12 adheres to the return spring 22 can also be reduced, so that the intake air amount controllability of the throttle valve 2 can be ensured stably. be able to.

(B-3) Minimization of Contact Area in Spring Attachment As described above, the return spring 22 is deformed so that the center in the radial direction is eccentric when the throttle valve 2 is operated in the valve opening direction. A part of 10A is provided on the radially inner peripheral side of the return spring 22, and a part shifted to the inner peripheral side of the return spring 22 is guided by the outer peripheral side 10Aa of the part provided on the inner peripheral side to suppress eccentricity. It has become.

Here, in the present embodiment, the outer peripheral side 10Aa of the spring mounting portion 10A (that is, the side that comes in contact with the return spring 22) that performs the guiding function as described above is reduced in diameter toward one end of the throttle shaft 6. When the return spring 22 is deformed and eccentric as described above, only the first row from the other end side 22b has its outer peripheral side 10b.
It is designed to abut Aa. Therefore, the contact area between the return spring 22 and the spring mounting portion 10A can be minimized, so that the abrasion powder described in (B-1) and the dust described in (B-2) adhere to the return spring 22 temporarily. In this case, it is possible to minimize the increase in friction and the promotion of wear of the return spring 22 itself. As a result, the occurrence of hysteresis in the deformation / return of the return spring 22 can be suppressed more reliably, and the controllability of the intake air amount of the throttle valve 2 can be more reliably and stably secured.

(B-4) Minimization of Contact Area in Outer Guide Part As described above, the return spring 22 is deformed so that its radial center is eccentric when the throttle valve 2 is operated in the valve opening direction. An outer guide portion 22a is provided, and a portion of the inner peripheral side which is shifted toward the outer peripheral side of the return spring 22 is guided to suppress eccentricity.

In the present embodiment, the outer guide portion 22a that performs the guide function as described above is
The diameter is increased toward one end, and only the first row from the one end 22a of the return spring comes into contact with the inner peripheral portion of the outer guide portion 23a. Therefore, the contact area between the return spring 22 and the outer guide portion 23a can be minimized, so that the wear powder described in (B-1) and the dust described in (B-2) adhere to the return spring 22 temporarily. In this case, it is possible to minimize the increase in friction and the promotion of wear of the return spring 22 itself. As a result, the occurrence of hysteresis in the deformation / return of the return spring 22 can be suppressed more reliably, and the controllability of the intake air amount of the throttle valve 2 can be more reliably and stably secured.

(B-5) Minimization of Contact Area in Inner Guide As described above, the return spring 22 is deformed so that its center in the radial direction is eccentric when the throttle valve 2 is operated in the valve opening direction. An inner guide portion 23b is provided on the inner surface of the return spring 22. The outer guide portion guides a portion shifted toward the inner circumferential side of the return spring 22 to suppress eccentricity.

In the present embodiment, the length of the inner guide portion 23b that performs the guiding function as described above in the direction of the throttle shaft 6 is
The length corresponds to a part of the total length in the direction (in this example, the pitch is equal to or less than the pitch of the return spring 22), and only the first row from one end 22a of the return spring 22 contacts the outer peripheral portion of the inner guide portion 23b. It is designed to be. Therefore, the contact area between the return spring 22 and the inner guide portion 23b can be minimized, so that the wear powder described in (B-1) and the dust described in (B-2) adhere to the return spring 22 temporarily. In this case, it is possible to minimize the increase in friction and the promotion of wear of the return spring 22 itself. As a result, the occurrence of hysteresis in the deformation / return of the return spring 22 can be suppressed more reliably, and the controllability of the intake air amount of the throttle valve 2 can be more reliably and stably secured. (B-6) Narrowing of Spring Insertion Portion 10B The radial interval between the outer guide portion 23a of the spring cover 23 and the spring insertion outer wall portion 10C is the outer guide portion 2
3a, the return spring 22, and the spring insertion outer wall portion 10C are designed to be minimized as long as they do not abut each other, so that abrasion powder, dust, and the like do not easily enter the spring insertion portion 10B. The adverse effect of the return spring 22 on the other end of the throttle shaft 6 can be prevented more reliably.

In the throttle valve device of the above embodiment, since the gear (C) 18 and the spring cover 23 are formed as separate members, the gear (C) 18, the spring cover 23, the return spring 22, The procedure for assembling the throttle shaft 6 to the throttle body 9 is as follows.

That is, first, the throttle shaft 6 is assembled to the throttle body 9 via the bearing 14 and the seal ring 24. Next, the other end side (the lower side in FIG. 4) 22b of the throttle shaft 6 of the return spring 22 is fixed to a cutout portion of the spring mounting portion 10A of the throttle body housing 10. At this time, the one end side (upper side in FIG. 4) 22a of the throttle shaft 6 of the return spring 22 is free.

Thereafter, the spring cover 23 and the gear (C) 18 are fitted to the oval-shaped shaft 6A of the throttle shaft 6.

Then, one end (upper side in FIG. 4) 22a of the throttle shaft 6 of the return spring 22 is cut out of the gear (C) 18 through a cutout 23B provided in the outer guide 23a of the spring holder 23. It is fixed to the portion 18c.

Finally, the bolt 6a is fastened via the seal ring 6b.

The above-described procedure is performed in the reverse order of → after the procedure. The oval-shaped hole 18A of the gear (C) 18 and the oval-shaped spring cover 23 are separate members. This is because it is not easy to assemble them together into the throttle shaft 6 because the holes 23A having the shape of (2) can freely rotate with each other.

However, as described above →→→
When the assembling work is performed in the order of →, since the spring cover 23 and the gear (C) 18 are fixed to the throttle shaft 6 in the order, the throttle end 22a of the return spring 22 is connected to the gear (C) 18 in the order. At the time of fixing, while receiving the urging force of the return spring 22, the return spring one end side 22a is pulled out with a jig through the spring cover notch 23B,
This is a complicated operation of fixing the gear (C) 18 to the cutout portion 18c, and it is difficult to improve the workability. In addition, the size of the spring cover notch 23B must be set relatively large for convenience in the pulling-out operation as described above, and it is regrettable that the original function of preventing abrasion powder and dust from coming down is reduced accordingly. is there.

In order to further improve such a point,
The gear (C) 18 and the spring cover 23 may be integrally configured as one member (gear / spring cover). FIG. 5 is a view showing the structure of the gear spring cover 25 according to such a modification, viewed from the same viewpoint as FIG. 3, and FIG. 6 is a cross-sectional view taken along the line VI-VI in FIG. . The same parts as those in the above embodiment are denoted by the same reference numerals. As shown in FIGS. 5 and 6, the gear / spring cover 25 includes a gear (C) portion 18 'corresponding to the gear (C) 18 and a spring cover portion 23' corresponding to the spring cover 23. ing.

In the above modification, the gear (C) portion 18 'constitutes second gear means fixed to the rotary shaft of the throttle valve, and the spring cover portion 23' described in the claims.
Is provided between the second gear means and the return spring, and constitutes dust-proof cover means for covering at least the side of the return spring facing the gear mechanism.

In the above modification, the gear (C) 18 and the spring cover 23 are integrally formed as one member (for example, formed by integral molding), so that the gear (C) 18 and the spring cover 23 are formed integrally. It is not necessary to consider the above-mentioned point that the two elements rotate freely with respect to each other.

Therefore, the above-mentioned procedure (1) is
The throttle shaft 6 is connected to the bearing 14 and the seal ring 24.
→ The one end 22a of the return spring 22 is fixed to the notch portion 18c of the gear (C) portion via the cutout portion 23B of the outer guide portion of the spring holder. → The other end 22b of the return spring is connected to the housing spring. The work can be easily performed in the order of fixing to the notch of the mounting portion 10A → fitting the gear / spring cover 25 to the throttle shaft 6A. It should be noted that these steps can be performed almost simultaneously or in the reverse order. Therefore, complicated work such as the work sequence of →→→ in the above-described embodiment can be eliminated, and workability can be improved, and productivity can be improved.

Also, the gear / spring cover 2 is
Before attaching the 5 to the throttle shaft 6, the return spring 23 can be passed through the spring cover notch 23B (see FIG. 4) in advance by a procedure, so that it is necessary to consider the convenience of the pull-out operation as described above. As a result, the size of the notch 23B can be minimized (for example, it can be reduced to the wire diameter of the return spring 23). Therefore, there is also an effect that a decrease in the action of preventing wear dust and dust from flying can be minimized.

[0076]

According to the present invention, it is possible to reduce the possibility that abrasion powder flying from the gear mechanism side adheres to the return spring, so that the flying abrasion powder adheres to the surface of the return spring to increase friction. Reduce the likelihood of
It is possible to suppress the occurrence of hysteresis in the deformation and return of the return spring. Therefore, it is possible to stably secure the intake air amount controllability of the throttle valve.

[Brief description of the drawings]

FIG. 1 is a vertical sectional view showing an entire structure of a throttle valve device according to an embodiment of the present invention.

FIG. 2 is a system conceptual diagram of a throttle valve device shown in FIG. 1 and a control system related thereto.

FIG. 3 is a side view of the structure in which a gear case is removed from the structure of FIG. 1 as viewed from a direction A in FIG. 1;

FIG. 4 is an exploded perspective view substantially corresponding to a cross-sectional view taken along line IV-IV in FIG.

FIG. 5 is a view showing a structure of a gear / spring cover in a modification in which the gear (C) and the spring cover are integrally formed as one member.

FIG. 6 is a cross-sectional view taken along the line VI-VI in FIG. 5;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Engine (internal combustion engine) 2 Throttle valve 5 Actuator 5a Output shaft 6 Throttle shaft (rotary shaft of throttle valve) 7 Gear mechanism 9 Throttle body 10 Housing 10A Spring mounting portion 10Aa Outer side (located on radial inner side of return spring) 11 Gear case 12 Drain hole 16 Gear (A) (first gear means) 18 Gear (C) (second gear means) 18 'Gear (C) part (second gear means) 22 Return Spring 22a One end side (one end side of the rotation axis of the return spring) 22b The other end side (the other end side of the rotation axis of the return spring) 23 Spring cover (cover means) 23 'Spring cover part (cover means) 23a Outer guide part 23b Inner guide Part 25 Gear / Spring cover

Continued on the front page (72) Inventor Kazuo Nagayama 2477 Takaba, Hitachinaka City, Ibaraki Prefecture Inside Hitachi Car Engineering Co., Ltd. (72) Inventor Katsutoshi Suganuma 2520 Takada, Hitachinaka-shi, Ibaraki F-term in the Automotive Equipment Group of Hitachi, Ltd. 3G065 CA00 CA34 DA05 DA06 DA15 FA12 GA41 GA46 HA06 HA12 HA15 HA21 HA22 KA02 KA14

Claims (6)

[Claims] A throttle valve rotatably disposed in a throttle body for controlling an intake air amount of the internal combustion engine; an actuator for generating a driving force; and an actuator provided at one end of a rotary shaft of the throttle valve. A gear mechanism that includes first gear means fixed to an output shaft of the actuator and second gear means fixed to a rotation axis of the throttle valve, and transmits a driving force of the actuator to a rotation axis of the throttle valve; The second gear means is provided on the other end side of the rotation shaft,
A throttle valve device for an internal combustion engine, comprising: a return spring that applies an urging force against a rotation operation in one direction of the gear unit; between the second gear unit and the return spring,
A throttle valve device for an internal combustion engine, further comprising dustproof cover means for covering at least a side of the return spring facing the gear mechanism. 2. A throttle valve device for an internal combustion engine according to claim 1, wherein a gear case provided on one end side of said rotary shaft of said throttle body to cover said gear mechanism, and said first gear means of a housing of said throttle body. A drain hole provided in at least one of a vicinity portion and a portion near the first gear means of the gear case, wherein the cover means also covers a side of the return spring facing the water drain hole. And a throttle valve device for an internal combustion engine. 3. The throttle valve device for an internal combustion engine according to claim 1, wherein one end of the rotation shaft of the return spring is fixed to the second gear unit, and the rotation shaft of the return spring and the like. An end side is fixed to a spring mounting portion provided on a housing of the throttle body. An outer peripheral side of a portion of the spring mounting portion located on a radially inner peripheral side of the return spring is connected to one end of the rotating shaft. A throttle valve device for an internal combustion engine, wherein the throttle valve device has a diameter decreasing toward a side. 4. The throttle valve device for an internal combustion engine according to claim 1, wherein one end of the rotation shaft of the return spring is fixed to the second gear means, and the rotation shaft of the return spring and the like. An end side is fixed to a spring mounting portion provided on a housing of the throttle body, and the cover means is located on an outer peripheral side in a radial direction of the return spring and guides a deformation operation of the return spring. A throttle valve device for an internal combustion engine, characterized in that the outer guide portion has a diameter increasing toward the other end of the rotary shaft. 5. The throttle valve device for an internal combustion engine according to claim 1, wherein one end of the rotation shaft of the return spring is fixed to the second gear unit, and the rotation shaft of the return spring and the like. An end side is fixed to a spring mounting portion provided on a housing of the throttle body, and the cover means is located on a radially inner peripheral side of the return spring and guides an inner guide for deforming the return spring. And a length of the inner guide portion in the rotation axis direction is a length corresponding to only a part of the entire length of the return spring in the rotation axis direction. Throttle valve device. 6. A throttle valve device for an internal combustion engine according to claim 1, wherein said second gear means and said cover means are integrally formed as one member. Valve device for an internal combustion engine.