JP2013181481A - Throttle device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a throttle device for holding a valve in horizontal opening without using motor drive, and capable of holding the valve in the horizontal opening when a motor is powered on.SOLUTION: A throttle device includes a stopper means 16 for regulating rotation in the opening direction rather than the horizontal opening of a valve 4, and applying biasing force in a closing direction to the valve 4. The valve 4 can be held in the horizontal opening by the stopper means 16 and an open spring 15 without using motor drive. Even when the valve is turned in the opening direction beyond the horizontal opening when returning the valve 4 to control fully-opened opening from a closing position by the motor drive, an impact due to a collision between a stopper part 17 and a stopper member 18 can be absorbed by the biasing force of the stopper means 16, so that there is no need to set the control fully-opened opening to the closing direction side more than machine fully-opened opening, the valve 4 can be held in the horizontal opening even when the motor is powered on.

Description

  The present invention relates to a throttle device for an internal combustion engine mounted on a vehicle such as an automobile.

Conventionally, a housing that forms a throttle bore having a circular cross section through which intake air flows, a shaft that has the radial direction of the throttle bore as an axial direction and is rotatably supported by the housing, and a throttle fixed to the shaft There is a throttle device that includes a disk-shaped valve that is disposed in a bore and adjusts the amount of intake air flowing through the throttle bore in accordance with the rotation angle of the shaft.
And in the throttle device for diesel engines, the normally open type throttle device is adopted.

  In a throttle device for a diesel engine, if the opening degree at which the valve plate surface is substantially horizontal in the axial direction of the throttle bore is the horizontal opening degree, the valve is held near the horizontal opening degree and can operate near the horizontal opening degree. Many. When the engine is stopped and EGR control is performed, the valve is rotated by the motor to one side in the rotation direction (closed direction).

Ideally, the valve is preferably always held at a horizontal opening, and Patent Document 1 discloses one means for holding the valve at a horizontal opening.
In the throttle device of Patent Document 1, the valve is held at a horizontal opening by driving a motor.

  That is, as shown in FIG. 8 (a), the throttle device regulates the movement of the valve 101 in the opening direction, and the open spring 102 that urges the valve 101 to the other side (opening direction) of the rotation direction. And a stopper 103 provided on the housing. The stopper 103 regulates the opening degree of the valve 101 when the valve gear 104 abuts on the stopper 103, and regulates the fully open position on the machine structure (machine fully open position) when the motor is not energized. Here, the full opening degree of the machine is set at a position slightly inclined in the opening direction from the axial direction of the throttle bore. And as shown in FIG.8 (b), the valve opening 101 is hold | maintained at the horizontal opening degree by the drive of a motor by making the full opening degree (control full opening degree) in operation into a horizontal opening degree.

  If the mechanical fully open position is made equal to the control fully open position, there will be variations in the rotation angle sensor, variations in the dimensions of the stopper 103 and the valve gear 104, etc., so that the valve 101 is controlled from the closed position by the motor drive. When returning to the opening degree, the valve gear 104 may hit the stopper 103. Further, the valve gear 104 may abut against the stopper 103 even when the motor is driven to swing more in the opening direction than the control full opening degree. If the valve gear 104 repeatedly hits the stopper 103, the stopper 103 may be worn, the valve gear 104 may be damaged, or the motor current may be burned out. Therefore, the control full opening degree is set in the closing direction rather than the mechanical full opening degree.

International Publication No. 2006/103784 Pamphlet

However, in the technique of Patent Document 1, since the valve 101 is held at a horizontal angle in the axial direction of the throttle bore by driving the motor, electric power for driving the motor is always required.
Therefore, in order to hold the valve 101 in a horizontal state without driving the motor, a method of setting the mechanical fully open degree to the horizontal degree is conceivable. However, in this case as well, since the control fully open position needs to be set closer to the closing direction than the mechanical fully open position, the valve 101 moves from the horizontal opening to the close direction when the control fully open position is applied when the motor is energized. Inclination and pressure loss of intake air will increase.

  The present invention has been made in order to solve the above-described problems. The purpose of the present invention is to maintain the valve in a horizontal opening regardless of the driving of the motor, and to keep the valve in a horizontal opening even when the motor is energized. To provide a throttle device that can be held.

  A throttle device according to a first aspect of the present invention includes a housing that forms a throttle bore having a circular cross section through which intake air flows, a shaft that has a radial direction of the throttle bore and is rotatably supported by the housing, and the shaft And a disc-shaped valve that is disposed on the throttle bore and adjusts the amount of intake air flowing through the throttle bore in accordance with the rotation angle of the shaft.

Here, the opening degree at which the plate surface of the valve becomes substantially horizontal in the axial direction of the throttle bore is defined as a horizontal opening degree, and one of the rotational directions is the open direction and the other rotational direction is the closed direction.
The throttle device regulates rotation in the opening direction rather than the horizontal opening of the valve, an open spring that applies a biasing force in the opening direction to the valve, a motor that generates a driving force for rotating the valve, And stopper means for applying a biasing force in the closing direction to the valve.

  The biasing force by the stopper means is larger than the biasing force of the open spring and smaller than the torque of the motor, and the valve is held at a horizontal opening by the stopper means and the open spring.

According to this, the valve can be held at the horizontal opening degree by the stopper means and the open spring regardless of the motor drive. That is, the full opening degree of the machine when the motor is not energized is set as the horizontal opening degree.
When the control fully open position is the horizontal opening, even if the valve is touched in the opening direction rather than the horizontal opening when returning the valve from the closed position to the control fully opened position by the motor drive, the stopper means is closed. Since the urging force is applied, the impact due to the restriction of the stopper means can be absorbed.
Therefore, the control full opening degree can be set to the horizontal opening degree, and the valve can be held at the horizontal opening degree even when the motor is energized.

According to the throttle device of the second aspect of the present invention, the stopper means is engaged with a rotating body (for example, a valve gear) whose one end rotates together with the valve, and applies a closing spring that applies a biasing force in the closing direction to the valve, The lever has a lever that can be engaged with the body in the closing direction, and is coupled to one end of the open spring and the other end of the close spring. And a stopper member that restricts rotation in the opening direction rather than the opening degree.
The torque of the motor is larger than the urging force of the open spring and the close spring.
According to the second aspect of the present invention, the same effect as that of the first aspect of the present invention is achieved.

(A) is front sectional drawing which shows the whole structure of a throttle device, (b) is a side view of the gear case of a throttle device (Example 1). It is explanatory drawing explaining the stopper means of a throttle device, (a) shows the state at the time of motor non-energization (at the time of a horizontal opening), (b) rotates a valve from a horizontal opening to a closing direction at the time of motor energization Indicates the state of the (Example 1). It is explanatory drawing explaining the stopper means of a throttle apparatus, and shows the state at the time of a valve | bulb swinging to an opening direction rather than a horizontal opening degree at the time of motor energization (Example 1). (Example 2) which is explanatory drawing explaining the structure of the stopper means of a throttle device. (Example 3) which is explanatory drawing explaining the structure of the stopper means of a throttle device. (Example 4) which is a perspective view explaining the stopper means of a throttle device. It is explanatory drawing explaining the structure of the stopper means of a throttle device (modification). (A)-(d) is explanatory drawing explaining the problem of the setting of the mechanical full open degree of a conventional throttle device, and a control full open degree.

  The mode for carrying out the present invention will be described in detail with reference to the following examples.

[Example 1]
[Configuration of Example 1]
The configuration of the throttle device 1 of this embodiment will be described with reference to FIGS.
The throttle device 1 of the present embodiment is a throttle device for a diesel engine, and is a valve device for adjusting the intake amount to the engine.
The throttle device 1 includes a housing 3 that forms a circular throttle bore 2 in which intake air flows therein, a disk-shaped valve 4 that is disposed in the throttle bore 2 and adjusts the amount of intake air flowing through the throttle bore 2, and this valve 4 A motor 5 that generates a driving force for rotating the motor 5, a gear reduction device 6 that transmits the rotational output of the motor 5 to the valve 4 and the shaft 9, and the like.

  The housing 3 is made of metal and forms a suction passage and a bore forming portion 3a that forms a throttle bore 2 that houses the valve 4, and a gear housing portion that houses the motor 5 and the gear reduction device 6 that drive the valve 4. 3b.

The valve 4 is a butterfly valve fixed to the shaft 9 and is formed in a disk shape from a metal material or a resin material.
The shaft 9 is made of a metal material and is rotatably supported by the housing 3 with the radial direction of the throttle bore 2 as an axial direction.

The motor 5 is an electric actuator (drive source) that can rotate the shaft 9 forward and backward when energized.
The gear reduction device 6 reduces the rotational speed of the motor 5 to a predetermined rotational speed of the shaft 9, and includes a valve gear 10 fixed to one end of the shaft 9, and an intermediate gear 11 that meshes with the valve gear 10 and rotates. The valve drive means has a pinion gear 12 fitted on the motor shaft of the motor 5 and rotationally drives the valve 4.
That is, when the valve gear 10 is rotated by receiving a driving force from the motor 5, the valve gear 10, the shaft 9 and the valve 4 are rotated together.

  The valve gear 10 is integrally formed in a predetermined substantially annular shape, and a gear portion 10a is formed on the outer periphery of the valve gear 10 in a predetermined range in the circumferential direction.

[Features of this embodiment]
Here, when the opening degree at which the plate surface of the valve 4 is substantially horizontal in the axial direction of the throttle bore 2 is defined as the horizontal opening degree, one of the rotation directions is the opening direction and the other rotation direction is the closing direction, the valve 4 is opened. The spring 15 is urged in the opening direction. When the motor 5 is not energized, the horizontal opening is held by the open spring 15 and the stopper means 16.

  The open spring 15 is formed of a spring steel material in a coil shape, and is arranged coaxially with the shaft 9 on the outer peripheral side of the shaft 9. One end is locked or held by the valve gear 10, and the other end is engaged with the housing 3. Stopped or held.

  The stopper means 16 is for restricting the valve 4 that is returned to the opening direction by the biasing force of the open spring 15 when the motor is not energized so that it does not rotate in the opening direction more than the horizontal opening.

  The stopper means 16 includes a stopper portion 17 provided on the valve gear 10, a stopper member 18 provided on the gear housing portion 3b so as to face the stopper portion 17 in the rotation direction, and the stopper member 18 on the stopper portion 17 side. And a spring 19 that biases the spring.

The stopper part 17 is provided in the opening direction edge part of the gear part 10a, and has a plane which faces an opening direction.
The stopper member 18 is a pin provided separately from the housing 3 so as to protrude toward the valve gear 10 from the inner peripheral surface of the portion of the gear housing portion 3b that accommodates the valve gear 10. The stopper member 18 has a bobbin shape, a head portion 18a that contacts the stopper portion 17, a base portion 18b guided in the housing 3, and an intermediate portion 18c having a small diameter between the head portion 18a and the base portion 18b. It is made up of. That is, a head portion 18a and a base portion 18b are provided in a flange shape at both ends of the rod-shaped intermediate portion 18c.

  The stopper member 18 is set at such a position that the stopper portion 17 can come into contact with the head 18 a of the stopper member 18 by the rotation of the valve gear 10. The head 18 a has a flat surface that can contact the flat surface of the stopper portion 17.

  The housing 3 has a housing portion 21 for holding the base portion 18b and the spring 19. The housing portion 21 houses the spring 19 and the cylindrical portion 21a that houses the base portion 18b, and the cylindrical portion 21a. Provided on the distal end side, the intermediate portion 18c can be inserted from the inside of the cylindrical portion 21a to the distal end side, and has a restricting portion 21b for restricting movement of the stopper member 18 to the distal end side by locking the base portion 18b. doing. The tip side is the side that abuts against the stopper portion 17 and is the closing direction in terms of the rotational direction.

The stopper member 18 is pressed toward the distal end side by a spring 19 that contacts the rear end surface of the base portion 18b.
In a state where the stopper member 18 is not pressed by the stopper portion 17, the base portion 18b is in contact with the restricting portion 21b (see FIG. 2A).

  The tip position of the stopper member 18 in this state, that is, the tip position in a state where the stopper member 18 is not pressed by the stopper portion 17 defines the opening degree of the valve 4 when the motor is not energized (FIG. 2 ( a)). The state in contact with the stopper member 18 at this tip position is the ideal fully open degree of the machine. In the present embodiment, the position of the tip of the stopper member 18 is defined so that the fully opened opening degree of the machine becomes the horizontal opening degree.

That is, when the motor is not energized, as shown in FIG. 2 (a), the horizontal opening that is the full opening degree of the machine is maintained by the balance of the urging forces of the open spring 15 and the spring 19.
The urging force by the stopper means 16 (the urging force in the closing direction by the spring 19) is larger than the urging force of the open spring 15 and smaller than the torque of the motor 5 on the shaft 9. That is, the biasing force of the spring 19 in the closing direction is larger than the biasing force of the open spring 15 in the opening direction, and the torque of the shaft 9 by the motor 5 is larger than the biasing force of the spring 19 in the closing direction.

  And when stopping an engine etc., as shown in FIG.2 (b), the drive force to a closing direction is provided to the valve gear 10 by motor energization. The motor 5 rotates the valve gear 10 in the closing direction from the horizontal opening degree against the urging force of the open spring 15. As a result, the intake passage is throttled by the valve 4.

In the present embodiment, the full opening degree (control full opening degree) when the motor is energized is the horizontal opening degree.
Therefore, when the motor 5 is instructed to hold the valve 4 at the control fully open position, ideally, the valve 4 is moved from the closed position to the horizontal position that is the control fully open position by driving the motor 5. Return to opening.
However, since there are variations in the rotation angle sensor and variations in the dimensions of the stopper portion 17 and the stopper member 18, etc., when the valve 4 is returned from the closed position to the control fully opened position by the motor drive, it is slightly smaller than the horizontal opening. There is a possibility that the rotation of the motor 5 may stop at a position where it swings in the opening direction.
In this case, the stopper portion 17 abuts against the stopper member 18, but as shown in FIG. 3, the spring 19 absorbs the collision between the stopper member 18 and the stopper portion 17 as the spring 19 contracts.

[Effect of this embodiment]
In this embodiment, there is provided stopper means 16 that restricts rotation in the opening direction rather than the horizontal opening of the valve 4 and applies a biasing force in the closing direction to the valve 4.
According to this, the valve 4 can be held at the horizontal opening degree by the stopper means 16 and the open spring 15 irrespective of the motor drive. That is, the full opening degree of the machine when the motor is not energized can be set as the horizontal opening degree.

  And the control full opening degree can also be made into a horizontal opening degree. That is, when the valve 4 is rotated in the opening direction by driving the motor and returned from the closed position to the control fully opened position, the stopper means 16 is biased in the closing direction even if it touches the opening direction rather than the horizontal opening degree. Therefore, the impact due to the collision between the stopper portion 17 and the stopper member 18 can be absorbed, so that it is not necessary to make the control fully open position closer to the closing direction than the mechanical fully open position as in the prior art. Therefore, the control full opening degree can be set to the horizontal opening degree, and the valve 4 can be held at the horizontal opening degree even when the motor is energized.

[Example 2]
A throttle device 1 according to the second embodiment will be described with reference to FIG. 4 with a focus on differences from the first embodiment. In addition, the same code | symbol as Example 1 shows the same structure, Comprising: The previous description is referred.
In the first embodiment, the head portion 18 a of the stopper member 18 has a flat surface that can contact the flat surface of the stopper portion 17. However, in this embodiment, as shown in FIG. 4, the head 18 a has a curved surface that protrudes toward the stopper portion 17, and this curved surface can contact the stopper portion 17.
According to this, there is no possibility that the stopper member 18 will come into contact with the stopper portion 17 and uneven wear of the stopper portion 17 can be prevented.

Example 3
The throttle device 1 according to the third embodiment will be described with reference to FIG. 5 with a focus on differences from the first embodiment. In addition, the same code | symbol as Example 1 shows the same structure, Comprising: The previous description is referred.
In this embodiment, the stopper means 16 includes a stopper portion 25 provided on the gear housing portion 3b, a stopper member 26 provided on the valve gear 10 so as to face the stopper portion 25 in the rotational direction, and the stopper member 26. And a spring 27 that urges the stopper portion 25 toward the stopper portion 25 side.
The stopper portion 25, the stopper member 26, and the spring 27 have the same functions as the stopper portion 17, the stopper member 18, and the spring 19 of the first embodiment, respectively.

The stopper portion 25 is provided in the gear housing portion 3b and has a flat surface facing the closing direction.
The stopper member 26 is accommodated together with the spring 27 in the accommodating portion 29 provided in the valve gear 10 so as to protrude in the opening direction from the opening direction end of the gear portion 10a. The stopper member 26 is urged toward the stopper portion 25 by a spring 27. The housing portion 29 is obtained by applying the same configuration as the housing portion 21 of the first embodiment to the valve gear 10.
According to this, when the valve 4 is returned from the closed position to the control fully opened position by driving the motor, even if the rotation of the motor 5 stops at a position slightly swung in the opening direction from the horizontal opening degree, the spring 27 The spring 27 absorbs the collision between the stopper member 26 and the stopper portion 25 by contracting and applying a biasing force in the closing direction to the valve gear 10.
Therefore, this embodiment also has the same effects as those of the first embodiment.

Example 4
A throttle device 1 according to the fourth embodiment will be described with reference to FIG. 6 with a focus on differences from the first embodiment. In addition, the same code | symbol as Example 1 shows the same structure, Comprising: The previous description is referred.
The stopper means 16 of the present embodiment is such that a close spring 31 that applies a biasing force in the closing direction to the valve 4 and a valve gear 10 (rotating body) can be engaged in the closing direction, and one end of the open spring 15 is provided. And a coupling member 32 that couples the other end of the close spring 31 and a stopper member 33 that is provided in the housing 3 and abuts against the coupling member 32 to restrict the rotation of the valve 4.

In this embodiment, one end of the open spring 15 is coupled to the close spring 31 via the coupling member 32, and the other end is locked or held by the housing 3.
The close spring 31 is formed of a spring steel material in a coil shape and is arranged coaxially with the open spring 15. One end of the close spring 31 is locked or held by the valve gear 10, and the other end is opened via a coupling member 32. Coupled with the spring 15.

The coupling member 32 has a substantially ring shape, and is disposed coaxially with the open spring 15 and the close spring 31 on the outer periphery of the shaft 9 so as to be rotatable relative to the valve gear 10. And it has the stopper part 32a which protrudes to radial direction at one place of the circumferential direction.
The coupling member 32 is opposed to the valve gear 10 in the axial direction across the close spring 31, and has a lever 32 b that protrudes from the surface on the valve gear 10 side toward the valve gear 10 on the outer periphery of the close spring 31.

  The valve gear 10 also has a lever 10e that protrudes from the surface on the coupling member 32 side to the coupling member 32 side on the outer periphery of the close spring 31, and the lever 10e can be engaged with the lever 32b in the closing direction. .

The stopper member 33 is provided in the housing 3 and abuts against the stopper portion 32a of the coupling member 32 when the valve 4 is opened horizontally and when the opening is larger than the horizontal opening. Regulates rotation to
The opening degree of the valve 4 when the stopper portion 32a and the stopper member 33 are in contact with each other is set so as to be a horizontal opening degree. The valve 4 is not driven by the motor, but by the stopper means 16 and the open spring 15. The horizontal opening is maintained.

Also in this embodiment, the control full opening is set to the horizontal opening.
Further, the torque by the motor 5 in the shaft 9 is larger than the urging force of the open spring 15 and the close spring 31.

[Effects of this embodiment]
Normally, the valve 4 can be held at a horizontal opening by the stopper means 16 and the open spring 15.
That is, the valve 4 can be held at a horizontal opening regardless of the motor drive, and the fully opened opening of the machine when the motor is not energized can be set as the horizontal opening.

  When the motor is energized, the valve 4 rotates in the closing direction against the urging force of the open spring 15 by the driving force of the motor 5. At this time, since the levers 32b and 10e are engaged and the valve gear 10 and the coupling member 32 do not rotate relative to each other, the urging force of the close spring 31 is not involved.

When the valve 4 is rotated in the opening direction by driving the motor and returned from the closed position to the control opening degree, the stopper portion 32 a comes into contact with the stopper member 33. Here, when the valve gear 10 is further rotated in the opening direction, the levers 32b and 10e are disengaged, so that a biasing force in the closing direction by the closing spring 31 is applied to the valve gear 10. The stopper portion 32a does not hit the stopper member 33 strongly.
For this reason, it is not necessary to make the control full opening degree closer to the closing direction than the mechanical full opening degree as in the prior art. Therefore, the control full opening degree can be set to the horizontal opening degree, and the valve 4 can be held at the horizontal opening degree even when the motor is energized.

[Modification]
In the first embodiment, the spring 19 is accommodated in the accommodating portion 21, and the stopper member 18 is pressed to the front end side by the spring 19 that contacts the rear end face of the base portion 18b. However, as shown in FIG. You may distribute | arrange between the head 18a and the control part 21b on the outer periphery of the intermediate part 18c. Also according to this aspect, the same effects as those of the first embodiment are obtained.

1 Throttle device 2 Throttle bore 3 Housing 4 Valve 5 Motor 9 Shaft 15 Open spring 16 Stopper means

Claims (4)

A housing (3) forming a throttle bore (2) having a circular cross section through which intake air flows;
A shaft (9) having a radial direction of the throttle bore (2) as an axial direction and rotatably supported by the housing (3);
A disc-shaped valve (4) fixed to the shaft (9) and disposed on the throttle bore (2) to adjust the amount of intake air flowing through the throttle bore (2) according to the rotation angle of the shaft (9). In the throttle device (1),
When the opening of the valve (4) is approximately horizontal in the axial direction of the throttle bore (2) is defined as a horizontal opening, one of the rotational directions is an open direction and the other of the rotational directions is a closed direction,
An open spring (15) for applying a biasing force in the opening direction to the valve (4);
A motor (5) for generating a driving force for rotating the valve (4);
Stopper means (16) for restricting rotation in the opening direction relative to the horizontal opening of the valve (4) and for applying a biasing force in the closing direction to the valve (4),
The biasing force by the stopper means (16) is larger than the biasing force of the open spring (15) and smaller than the torque of the motor (5),
The throttle device according to claim 1, wherein the valve (4) is held at the horizontal opening by the stopper means (16) and the open spring (15). The throttle device according to claim 1, wherein
Comprising a valve gear (10) rotating with the shaft (9);
The housing (3) has a gear housing part (3b) for accommodating the valve gear (10),
The stopper means (16)
A stopper portion (17) provided on either the valve gear (10) or the gear housing portion (3b);
A stopper member (18) provided on the other of the valve gear (10) and the gear housing portion (3b) so as to face the stopper portion (17) in the rotation direction;
A spring (19) provided on either the valve gear (10) or the gear housing part (3b) and biasing the stopper member (18) toward the stopper part (17). Throttle device. The throttle device according to claim 2,
The throttle device according to claim 1, wherein a tip of the stopper member (18) facing the stopper portion (17) is formed as a curved surface that protrudes toward the stopper portion (17). A housing (3) forming a throttle bore (2) having a circular cross section through which intake air flows;
A shaft (9) having a radial direction of the throttle bore (2) as an axial direction and rotatably supported by the housing (3);
A disc-shaped valve (4) fixed to the shaft (9) and disposed on the throttle bore (2) to adjust the amount of intake air flowing through the throttle bore (2) according to the rotation angle of the shaft (9). In the throttle device (1),
When the opening of the valve (4) is approximately horizontal in the axial direction of the throttle bore (2) is defined as a horizontal opening, one of the rotational directions is an open direction and the other of the rotational directions is a closed direction,
An open spring (15) for applying a biasing force in the opening direction to the valve (4);
A motor (5) for generating a driving force for rotating the valve (4);
Stopper means (16) for restricting rotation in the opening direction relative to the horizontal opening of the valve (4) and for applying a biasing force in the closing direction to the valve (4),
The stopper means (16)
A close spring (31), one end of which is locked to a rotating body (10) that rotates together with the valve (4) and applies a biasing force in a closing direction to the valve (4);
It has a lever (32b) engageable with the rotating body (10) in the closing direction, and a coupling portion (32) for coupling one end of the open spring (15) and the other end of the close spring (31). )When,
A stopper member (33) that is provided in the housing (3) and restricts rotation of the valve (4) in the opening direction rather than the horizontal opening degree by contacting the coupling portion (32); ,
The torque of the motor (5) is larger than the urging force of the open spring (15) and the close spring (31),
The throttle device according to claim 1, wherein the valve (4) is held at the horizontal opening by the stopper means (16) and the open spring (15).

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