JP2014137005A - Valve device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To miniaturize a valve device in an axial direction.SOLUTION: An EGRV 1 comprises: an intermediate member 25 arranged on a shaft 3 relatively rotatably; a first torsion spring 26 with one end fixed to a housing 2 and other end fixed to the intermediate member 25, and that gives an energization force to the valve 4 on one side in a rotation direction; and a second torsion spring 27 with one end fixed to the intermediate member 25 and other end fixed to a valve gear 19, and that gives an energization force to the valve 4 on the other side in the rotation direction. The intermediate member 25 has a ring-like shape, and is arranged on an outer periphery of a fitting part 19a of the valve gear 19 relatively rotatably to the valve gear 19. In an axial direction of the shaft 3, the valve gear 19 and the intermediate member 25 are overlaid on each other. Thus, there is no need for providing a space for arranging the intermediate member 25 on the shaft 3, so that axial length of the shaft 3 can be reduced. Thereby, the EGRV 1 can be miniaturized in the axial direction.

Description

  The present invention relates to a valve device that opens and closes a flow path by a valve and adjusts a flow rate by a valve opening degree.

  As shown in FIG. 2, as a conventional valve device 100, a housing that forms a flow path, a shaft 101 that is rotatably supported by the housing, and a valve 102 that is fixed to the shaft 101 and adjusts the opening of the flow path. A motor that generates a driving force for rotating the shaft 101, a valve gear 103 that is fixed to the shaft 101 and rotates by receiving the driving force of the motor, and an intermediate member 104 that is arranged to be relatively rotatable with respect to the shaft 101. A first torsion spring 105 provided between the housing and the intermediate member 104 to apply a biasing force on one side in the rotational direction to the valve 102; and fixed to the intermediate member 104 and the valve gear 103 to rotate with respect to the valve. Some include a second torsion spring 106 that applies a biasing force on the other side of the direction (see Patent Document 1).

  The intermediate member 104 rotates together with the valve gear 103 when the valve 102 rotates from the predetermined opening to the other side in the rotation direction, and the intermediate member 104 and the valve gear 103 when the valve 102 rotates from the predetermined opening to the one side in the rotation direction. The engagement is released and the rotation is restricted by the housing.

That is, when the valve 102 rotates from the predetermined opening degree (for example, the fully closed position) to the other side (open side) in the rotation direction, the intermediate member 104 is engaged with the valve gear 103 via the lever 108, The member 104 rotates together with the valve gear 103, and the valve 102 rotates while resisting the urging force of the first torsion spring 105.
When the valve 102 rotates from the predetermined opening degree (fully closed position) to one side (overturn side) in the rotation direction, the lever 108 is disengaged and the intermediate member 104 is attached to the stopper 109 formed in the housing. Engage. As a result, the valve 102 rotates while resisting the biasing force of the second torsion spring 106.

JP 2001-303978 A

  By the way, in the valve device 100 described in Patent Document 1, the intermediate member 104 is disposed on the shaft 101, and the intermediate member 104 and the valve gear 103 are arranged in the axial direction of the shaft 101. For this reason, in order to ensure the space which distributes the intermediate member 104 to the shaft 101, it is necessary to lengthen the axial direction length of the shaft 101, and as a result, the axial direction length of the valve apparatus 100 increases.

  The present invention has been made to solve the above-described problems, and an object thereof is to reduce the axial size of a valve device having an intermediate member.

  The valve device of the present invention generates a housing that forms a flow path, a shaft that is rotatably supported by the housing, a valve that is fixed to the shaft and adjusts the opening of the flow path, and a driving force that rotates the shaft. Motor, a valve gear that is fixed to the shaft and rotates by receiving the driving force of the motor, an intermediate member that is arranged to be relatively rotatable with respect to the shaft, one end fixed to the housing, and the other end fixed to the intermediate member A first torsion spring that applies a biasing force on one side in the rotational direction to the valve, one end fixed to the intermediate member, the other end fixed to the valve gear, and a biasing force on the other side in the rotational direction to the valve. A second torsion spring to be applied.

The intermediate member has a lever that engages with the valve gear when the valve is on the other side in the rotational direction from the predetermined opening.
The housing has a stopper that restricts relative rotation between the intermediate member and the housing when the valve is on one side in the rotational direction from the predetermined opening.
The valve rotates against the urging force of the first torsion spring when it is on the other side of the rotation direction from the predetermined opening, and against the urging force of the second torsion spring when it is on one side of the rotation direction from the predetermined opening. Move.

  The intermediate member is disposed on the outer periphery of the valve gear, and the valve gear and the intermediate member overlap in the axial direction of the shaft.

  According to this, it is not necessary to provide a space for arranging the intermediate member on the shaft, and the axial length of the shaft can be shortened. Thereby, the valve device can be miniaturized in the axial direction.

(A) is sectional drawing of a valve apparatus, (b) is the elements on larger scale of (a) (Example 1). It is explanatory drawing of a valve apparatus (conventional example).

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

An embodiment will be described with reference to FIG.
The valve device 1 of this embodiment is employed in an EGR system that circulates a part of exhaust gas from a combustion chamber of an internal combustion engine to an intake passage, and adjusts the flow rate of exhaust gas to be circulated (hereinafter referred to as EGRV1). Called).

  The EGRV 1 is a housing 2 that forms a part of a recirculation path for returning exhaust gas to an intake passage of an internal combustion engine, a shaft 3 that is rotatably accommodated in the housing 2, and is supported and fixed to the shaft 3. A disc-shaped valve 4; an actuator 5 that drives the valve 4 via the shaft 3; an opening sensor 6 that detects the opening of the valve 4; and a control means that generates and outputs a control signal to the actuator 5. Have.

The housing 2 includes a flow path forming portion 10 that forms a flow path 9 that is a part of the reflux path, and a main body portion 11 that houses the shaft 3 and the actuator 5.
The flow path forming part 10 forms a flow path 9 having a circular cross section, and the main body part 11 holds the shaft 3 rotatably via a bearing 12 so that one end of the shaft 3 projects into the flow path 9. Yes.

  The valve 4 is formed in a disc shape and is fixed to one end of the shaft 3. When the shaft 3 rotates, the valve 4 opens and closes the flow path, and the flow rate is adjusted by the opening degree of the valve 4.

  The actuator 5 includes an electric motor 14 that generates a driving force upon receiving electric power, and a power transmission mechanism 15 that transmits the rotational motion of the output shaft 14 a of the electric motor 14 to the shaft 3.

The power transmission mechanism 15 is a gear reduction mechanism that reduces the rotational speed of the output shaft 14a to a predetermined reduction ratio. The pinion gear 17 fixed to the outer periphery of the output shaft 14a, An intermediate reduction gear 18 that rotates while meshing with it, a valve gear 19 that rotates while meshing with this intermediate reduction gear 18, and the like.
The valve gear 19 is fixed to the other end of the shaft 3, and has a fitting portion 19 a that fits to the outer periphery of the shaft 3, and gear teeth that mesh with the intermediate reduction gear 18 at the other axial end of the fitting portion 19 a. A gear tooth portion 19b.

  The opening sensor 6 includes a pair of magnets 21 attached to the valve gear 19 and a Hall IC 22 disposed in the vicinity of the magnet 21, and opens the valve 4 using the output change characteristic of the Hall IC 22 with respect to the rotation of the magnet 21. This is a non-contact rotation angle detection device that detects the degree. Instead of the Hall IC 22, a non-contact type magnetic detection element such as a Hall element alone or a magnetoresistive element may be used.

  The control means is an ECU that performs energization control of the electric motor 14. The ECU includes functions such as a CPU for performing control processing and arithmetic processing, a storage device (memory such as ROM and RAM) for storing various programs and various data, an input circuit (input unit), an output circuit (output unit), and the like. There is provided a microcomputer having a well-known structure.

  The control means outputs a control signal to the electric motor 14 so as to obtain a desired flow rate based on the sensor output from the opening sensor 6 and a predetermined opening-flow rate correlation stored in advance. Take control. That is, when the sensor output from the opening sensor 6 is input, the electric motor 14 is set so that the valve opening detected by the opening sensor 6 substantially matches the opening target value necessary to obtain a desired flow rate. A control signal (such as supply power) is generated.

[Features of this embodiment]
The EGRV 1 has an intermediate member 25 arranged to be rotatable relative to the shaft 3, one end fixed to the housing 2, the other end fixed to the intermediate member 25, and a biasing force on one side of the rotation direction with respect to the valve 4. And a second torsion spring 27 having one end fixed to the intermediate member 25 and the other end fixed to the valve gear 19 and applying a biasing force on the other side in the rotational direction to the valve 4. I have.

  The intermediate member 25 has a ring shape, and is disposed on the outer periphery of the fitting portion 19 a of the valve gear 19 so as to rotate relative to the valve gear 19. That is, the valve gear 19 and the intermediate member 25 overlap in the axial direction of the shaft 3.

The intermediate member 25 includes a cylindrical cylindrical portion 25a, an inner flange 25b extending from one axial end of the cylindrical portion 25a to the inner peripheral side of the cylindrical portion 25a, and an axial other end of the cylindrical portion 25a to the cylindrical portion 25a. An outer flange 25c extending to the outer peripheral side is provided.
The first torsion spring 26 is disposed on the outer periphery of the cylindrical portion 25a between the spring locking portion 30 formed in the housing 2 and the outer flange 25c.
The second torsion spring 27 is disposed on the inner periphery of the cylindrical portion 25 a between the inner flange 25 b and a spring locking portion 31 formed at the other end of the fitting portion 19 a of the valve gear 19.

The intermediate member 25 has a lever (not shown) that engages with the valve gear 19 when the valve 4 is rotated from the fully closed position to the other side in the rotational direction (hereinafter referred to as the open side).
The housing 2 is a stopper (not shown) that restricts relative rotation between the intermediate member 25 and the housing 2 when the valve 4 is rotated from the fully closed position to one side in the rotational direction (hereinafter referred to as overturn side). Have
Note that the lever and the stopper have the same function as the lever 108 and the stopper 109 of the conventional example (see FIG. 2).

  The stopper sets the default opening on the opportunity structure of the valve 4 by bringing the intermediate member 25 into contact with the stopper by the biasing force of the first torsion spring 26 when the electric motor 14 is not energized. In the embodiment, the default opening is the fully closed position.

The valve 4 resists the urging force of the first torsion spring 26 when rotating from the fully closed position to the open side, and the second torsion spring 27 when rotating from the fully closed position to the overturn side. It rotates against the biasing force.
In addition, the valve 4 adjusts the opening degree of the flow path 9 by rotating from the fully closed position to the open side. The rotation from the fully closed position to the overturn side is used to scrape off when soot or the like adheres to the channel wall surface.

[Effects of Example]
In this embodiment, the intermediate member 25 is disposed on the outer periphery of the fitting portion 19 a of the valve gear 19, and the entire intermediate member 25 overlaps the valve gear 19 in the axial direction of the shaft 3.
According to this, it is not necessary to provide a space for arranging the intermediate member 25 on the shaft 3, and the axial length of the shaft 3 can be shortened. Thereby, EGRV1 can be reduced in size in the axial direction.

[Modification]
The valve device of the present embodiment is EGRV1, but is not limited to this, and may be, for example, a throttle valve device that opens and closes an intake passage of an internal combustion engine.

1 EGRV (valve device), 2 housing, 3 shaft, 4 valve, 9 flow path, 14 electric motor, 19 intermediate member, 25 intermediate member, 26 first torsion spring, 27 second torsion spring

Claims (2)

A housing (2) forming a flow path (9);
A shaft (3) rotatably supported by the housing (2);
A valve (4) fixed to the shaft (3) for adjusting the opening of the flow path (9);
A motor (14) for generating a driving force for rotating the shaft (3);
A valve gear (19) fixed to the shaft (3) and rotated by receiving the driving force of the motor (14);
An intermediate member (25) arranged to be rotatable relative to the shaft (3);
A first torsion spring (26) having one end fixed to the housing (2) and the other end fixed to the intermediate member (25), and applying a biasing force on one side in the rotational direction to the valve (4); ,
A second torsion spring (27) having one end fixed to the intermediate member (25), the other end fixed to the valve gear (19), and applying a biasing force on the other side in the rotational direction to the valve (4); With
The intermediate member (25) has a lever that engages with the valve gear (19) when the valve (4) rotates from the predetermined opening to the other side in the rotation direction,
The housing (2) is provided with a stopper for restricting relative rotation between the intermediate member (25) and the housing (2) when the valve (4) is rotated to one side in the rotational direction from the predetermined opening. Have
The valve (4) resists the urging force of the first torsion spring (26) when it is on the other side in the rotational direction from the predetermined opening, and the valve (4) is on the first side in the rotational direction from the predetermined opening. A valve device that rotates against a biasing force of two torsion springs (27),
The intermediate member (25) is disposed on the outer periphery of the valve gear (19), and the valve gear (19) and the intermediate member (25) overlap each other in the axial direction of the shaft (3). Valve device to do. The valve device according to claim 1,
The valve device, wherein the flow path (9) is a recirculation path for circulating a part of the exhaust gas from the combustion chamber of the internal combustion engine to the intake path.