JP6771400B2 - Valve drive actuator and valve drive device - Google Patents

Description

The present invention relates to an actuator provided with a mechanism for regulating the movement of the shaft.

Actuators that convert the rotary motion of the rotor into the linear motion of the shaft are known. Further, for example, Patent Document 1 describes that such an actuator is provided with a mechanism for regulating the movement of the shaft. Specifically, a mechanism that regulates the rotational movement of the shaft, a mechanism that regulates the movement of the shaft in the valve opening direction, and a mechanism that regulates the movement of the shaft in the valve closing direction are described.

Japanese Unexamined Patent Publication No. 2016-197978

In an actuator provided with a mechanism for regulating the movement of the shaft as described above, when the constituent members of the mechanism come into contact with each other, an impact force is generated due to the contact. Patent Document 1 describes that the link mechanism or bracket is made of an elastic member, the female thread part is made of a resin material, and a spring member is installed between the bearing part and the housing part. It is said that the impact transmitted from the waist gate valve is absorbed in this way. As described above, Patent Document 1 describes a configuration for absorbing the generated impact at a subsequent stage. However, this configuration does not attempt to reduce the original impact itself generated by generating a small impact instead of a large impact when an impact is generated. In other words, the configuration does not attempt to mitigate the impact force itself. That is, in the above-mentioned Patent Document 1, consideration has not been given to alleviating the generated impact force, for example, the impact force itself generated when the constituent members of the mechanism for regulating the movement of the shaft come into contact with each other.

The present invention has been made to solve the above problems, and an object of the present invention is to obtain an actuator capable of alleviating the impact force itself generated by abutting the constituent members of a mechanism for regulating the movement of the shaft. ..

The valve drive actuator according to the present invention has a rotor having a female screw portion inside and rotating, and a male screw portion that meshes with the female screw portion, and converts the rotational movement of the rotor into a linear motion along the axial direction and outputs the rotor. A closed-side regulating mechanism having a shaft, a closed-side stopper, and a first contact portion of the shaft that contacts the closed-side stopper and restricting the movement of the shaft in the valve closing direction, an open-side stopper and the open-side stopper. An open side regulating mechanism that has a second contact portion of the shaft that comes into contact and regulates the movement of the shaft in the valve opening direction, or a rotary stopper that has a flat surface and a shaft that has a flat surface in contact with the flat surface. 3 It has a contact portion and a rotation regulation mechanism that regulates the rotation of the shaft around the axis, and the closed side regulation mechanism, the open side regulation mechanism, or the rotation regulation mechanism is one of the two constituent members that abut each other. , The constituent member on the side with which the shaft comes into contact is an elastic body fixed by adhesion or insert molding .

According to the present invention, the closed-side regulating mechanism, the open-side regulating mechanism, or the rotation-regulating mechanism, which is a mechanism for regulating the movement of the shaft, has an elastic body at least one of two abutting constituent members. It is possible to alleviate the impact force itself generated by the contact between the constituent members of the mechanism that regulates the movement of the.

It is sectional drawing of the actuator which concerns on Embodiment 1 of this invention. It is an enlarged view of the part A in FIG. It is sectional drawing along the line BB in FIG. It is a graph which shows the valve closing speed of the actuator which concerns on Embodiment 1 of this invention.

Embodiment 1.
FIG. 1 is a cross-sectional view of the actuator 1 according to the first embodiment of the present invention. FIG. 1 shows a case where the actuator 1 is used as the WG actuator for driving the waist gate (hereinafter referred to as WG) valve 102 of the turbocharger mounted on the vehicle.

The actuator 1 has a rotor 3 in a space surrounded by a case 2. The rotor 3 includes a rotor core 30 in which a large number of magnetic steel plates are laminated and integrated, a coil 31 wound around the rotor core 30, a cylindrical pipe 32 provided inside the rotor core 30, and a cylindrical shape inside the pipe 32. It has a resin member 33 provided in. The inner peripheral surface of the resin member 33 has a female screw shape, whereby the female screw portion 34 is formed inside the rotor 3. Both ends of the pipe 32 project from the rotor core 30, the upper end on the paper surface is rotatably supported by the bearing 3a, and the lower end on the paper surface is rotatably supported by the bearing 3b. The rotor core 30, the pipe 32, and the resin member 33 are fixed to each other and rotate integrally as the rotor 3.

The shaft 4 penetrates the rotor 3. A part of the outer peripheral surface of the shaft 4 is male-threaded, whereby the shaft 4 has a male-threaded portion 40 that meshes with the female-threaded portion 34. The lower end of the shaft 4 on the paper surface protrudes from the case 2. The shaft 4 is made of, for example, stainless steel.

A boss 5 is provided on the lower side of the paper when viewed from the rotor 3. The boss 5 is fixed to the case 2. The boss 5 is penetrated by the shaft 4. Most of the boss 5 is made of resin.
A commutator 6 is provided on the upper side of the paper when viewed from the rotor 3. The commutator 6 is fixed to the rotor 3.
On the outer peripheral side when viewed from the rotor 3, the magnet 7 and the yoke 8 are fixed to the case 2.

In the actuator 1 configured as described above, when a voltage is applied to the external terminal 9, a current flows through the commutator 6 and then the coil 31 via the brush connected to the external terminal 9, and the commutator 6 and the rotor 3 and 3 rotate integrally. Although the case where the brushed DC motor is mounted on the actuator 1 is shown in FIG. 1, the actuator 1 may be configured by other motors.
When the rotor 3 rotates, the shaft 4 having the male threaded portion 40 that meshes with the female threaded portion 34 of the rotor 3 moves along the axial direction of the shaft 4. In this way, the shaft 4 converts the rotational motion of the rotor 3 into a linear motion along its own axial direction and outputs it. In the actuator 1, the side on which the shaft 4 protrudes, and the lower side in FIG. 1 is the output side.

As shown in FIG. 1, a case where the actuator 1 drives the WG valve 102 of the turbocharger will be described below as an example. The turbocharger rotates a turbine by exhaust gas from the engine and drives a compressor coaxially connected to the turbine to compress intake air and supply it to the engine. On the upstream side of the turbine of the exhaust passage 100, a WG valve 102 that allows exhaust gas to escape from the exhaust passage 100 to the bypass passage 101 is installed, and the actuator 1 opens and closes the WG valve 102 to move from the exhaust passage 100 to the bypass passage 101. By adjusting the amount of exhaust gas inflow, the rotation speed of the turbine is controlled.

The actuator 1 drives the WG valve 102 via the link mechanism 103. The link mechanism 103 has two plates 103a and 103b. The shaft 4 is attached to one end side of the plate 103a, and the plate 103b is rotatably attached to the other end side of the plate 103a. When the rotor 3 rotates in one direction and the shaft 4 moves downward on the paper surface, the plate 103a also moves downward. Then, the plate 103b and the WG valve 102 rotate, and the WG valve 102 opens. On the other hand, when the rotor 3 rotates in the opposite direction and the shaft 4 moves upward on the paper surface, the plate 103a also moves upward. Then, the plate 103b and the WG valve 102 rotate, and the WG valve 102 closes. In this way, the actuator 1 and the WG valve 102 form a valve drive device.
In FIG. 1, the fully closed state of the WG valve 102 is shown by a solid line, and the fully open state of the WG valve 102 is shown by a two-dot chain line. That is, in FIG. 1, the downward direction on the paper surface is the valve opening direction for the shaft 4, and the upward direction on the paper surface is the valve closing direction for the shaft 4.

Here, FIG. 2 shows an enlarged cross-sectional view of the portion A in FIG. 1.
The position of the shaft 4 shown in FIGS. 1 and 2 is a position in a fully closed state. At this time, as shown in FIG. 2, the first contact portion 41 of the shaft 4 comes into contact with the lower tip of the female screw portion 34, and the shaft 4 is restricted from moving further in the valve closing direction. .. That is, the lower tip of the female screw portion 34 functions as a closing stopper. In this way, the closing side stopper and the first contact portion 41 form a closing side regulating mechanism that regulates the movement of the shaft 4 in the valve closing direction.

Further, when the shaft 4 moves in the valve opening direction from the state shown in FIGS. 1 and 2, the shaft 4 eventually comes into contact with the bottom portion 50 inside the boss 5 with the second contact portion 42. As a result, the shaft 4 is restricted from moving further in the valve opening direction. That is, the bottom portion 50 of the boss 5 functions as an open side stopper. As described above, the opening side stopper and the second contact portion 42 form an opening side regulating mechanism that regulates the movement of the shaft 4 in the valve opening direction.

Further, FIG. 3 shows a cross-sectional view of the shaft 4 cut along the line BB in FIG. The shaft 4 has two flat surfaces 43a and 43b on its outer peripheral surface. Further, the boss 5 has two flat surfaces 51a and 51b on its inner peripheral surface. When the shaft 4 moves, the flat surfaces 43a and 43b come into contact with the flat surfaces 51a and 51b, so that the shaft 4 is restricted from rotating around the axis by being caught by the rotation of the rotor 3, and the shaft 4 is a shaft. It becomes easier to move smoothly along the direction. That is, the portion inside the boss 5 having the flat surfaces 51a and 51b functions as a rotation stopper. Further, the portion of the shaft 4 having the flat surfaces 43a and 43b and having the flat surfaces 43a and 43b in contact with the flat surfaces 51a and 51b becomes the third contact portion of the shaft 4. In this way, the rotation stopper and the third contact portion form a rotation regulation mechanism that regulates the rotation of the shaft 4 around the axis. In FIG. 3, the outer peripheral surface of the shaft 4 and the inner peripheral surface of the boss 5 are drawn in close contact with each other, but there is actually a slight gap so that the shaft 4 can move along the axial direction. It is provided.

The closed-side regulation mechanism, the open-side regulation mechanism, and the rotation regulation mechanism function as their respective mechanisms when one component abuts on the other component. For example, in the closing side regulation mechanism, the first contact portion 41 of the shaft 4 which is one constituent member comes into contact with the tip of the female screw portion 34 which is the other constituent member, so that the shaft 4 moves in the valve closing direction. Is regulated. Therefore, when the two constituent members come into contact with each other, an impact force is generated due to the contact.

Therefore, in the first embodiment, the tip of the female screw portion 34 with which the first contact portion 41 contacts, the bottom portion 50 of the boss 5 with which the second contact portion 42 contacts, and the flat surface with which the third contact portion contacts. The portion of the boss 5 having 51a and 51b is made of an elastic body such as rubber. The elastic body is fixed as a part of the resin member 33 or a part of the boss 5 by adhesion, insert molding, or the like. In this way, in the resin member 33 and the boss 5, the portion where the first contact portion 41, the second contact portion 42, or the third contact portion abuts is partially made into an elastic body, whereby the closed side regulation mechanism , The impact force generated when the open side regulation mechanism and the rotation regulation mechanism function is reduced. In other words, the generated impact force itself can be mitigated.

This eliminates the need for control that alleviates the impact force itself generated by the closing side regulating mechanism by slowing down the moving speed of the shaft 4, for example, when the valve is closed. Therefore, the valve closing speed becomes faster. FIG. 4 is a graph showing the speeding up of the valve closing speed by the actuator 1. The vertical axis of the graph shows the amount of protrusion of the shaft 4 from the case 2. FIG. 4 shows a state in which the tip of the female threaded portion 34 to which the first contacting portion 41 abuts is an elastic body, and the tip is left in the same resin as other parts of the resin member 33. The state is shown by a broken line. The time from an arbitrary valve opening position to a fully closed position is shorter in the solid line due to the difference in the magnitude of the impact force generated when the first contact portion 41 contacts the tip of the female screw portion 34. Can be done.

Similarly, when the valve is opened, it is not necessary to control the shaft 4 by slowing down the moving speed to alleviate the impact force itself generated by the opening side regulating mechanism. Therefore, the valve opening speed becomes faster. In addition, the impact force itself generated when the rotation regulation mechanism functions is alleviated also contributes to increasing the valve closing speed and the valve opening speed. That is, according to the actuator 1 according to the first embodiment, the responsiveness can be improved.

Further, since the tip of the female threaded portion 34 with which the first contacting portion 41 abuts is made of an elastic body, the first one is compared with the case where the tip is made of the same resin as other parts of the resin member 33. It is possible to suppress the possibility of damage to the tip of the female screw portion 34 and the resin member 33 due to the contact with the contact portion 41. The same can be said for the bottom 50 of the boss 5 with which the second contact portion 42 contacts and the inner peripheral surface of the boss 5 with which the third contact portion contacts.

In the above, the case where the actuator 1 is used as the WG actuator for driving the WG valve 102 is shown. However, the actuator 1 may be used to drive a valve other than the WG valve 102. For example, the actuator 1 may drive an EGR (Exhaust Gas Recirculation) valve. Further, the actuator 1 may drive a valve for switching the turbocharger that supplies the exhaust gas when a plurality of turbochargers such as a twin turbo are used.

Further, in the above, rubber has been mentioned as an example of the elastic body, but an elastic body other than rubber may be used. In short, if it is more elastic than the resin constituting most of the resin member 33 and the boss 5, it contributes to alleviating the generated impact force itself.

Further, in the above, the tip of the female screw portion 34 on the side where the first contact portion 41, the second contact portion 42 or the third contact portion of the shaft 4 abuts, the bottom portion 50 of the boss 5, and the flat surface 51a. The portion 51b was assumed to be an elastic body. However, the first contact portion 41, the second contact portion 42, and the third contact portion of the shaft 4 may be elastic bodies. That is, for example, the elastic body is partially arranged on the stainless steel shaft 4. In short, it is sufficient that at least one of the two constituent members in contact with each other is an elastic body in each of the closed-side regulating mechanism, the open-side regulating mechanism, and the rotation regulating mechanism.

Further, in the above, the case where the actuator 1 includes a closed side regulating mechanism, an open side regulating mechanism, and a rotation regulating mechanism is shown. However, the actuator 1 may include only any two or one of these three mechanisms depending on the usage conditions of the actuator 1.

Further, in the above, the case where the actuator 1 is provided with the closed side regulating mechanism, the open side regulating mechanism and the rotation regulating mechanism in the portion A in FIG. 1 is shown. However, depending on the structure of the actuator 1, the actuator 1 may include, for example, a closing side regulating mechanism, an opening side regulating mechanism, and a rotation regulating mechanism in the portion C in FIG. In this case, the actuator 1 is provided with a contact portion corresponding to a first contact portion 41, a second contact portion 42, and a third contact portion at an arbitrary portion of the shaft 4 in the portion C, and is provided in the portion C. For example, the pipe 32 is provided with a configuration in which the tip of the female screw portion 34, the bottom portion 50 of the boss 5, and the contact portions correspond to the flat surfaces 51a and 51b.

As described above, according to the first embodiment of the present invention, the mechanisms that regulate the movement of the shaft 4, such as the closed side regulating mechanism, the open side regulating mechanism, and the rotation regulating mechanism, are among the two constituent members that come into contact with each other. At least one of them is an elastic body. Therefore, when the movement of the shaft 4 in the valve closing direction, the movement of the shaft 4 in the valve opening direction, the rotation of the shaft 4 around the axis, and the like are regulated, the constituent members of the respective mechanisms come into contact with each other. The impact force becomes smaller, and the impact force itself can be alleviated.

In the present invention, within the scope of the invention, it is possible to modify any component of the embodiment or omit any component of the embodiment.

1 Actuator, 2 Case, 3 Rotor, 3a, 3b Bearing, 4 Shaft, 5 Boss, 6 Commutator, 7 Magnet, 8 Yoke, 9 External Terminal, 30 Rotor Core, 32 Pipe, 33 Resin Member, 34 Female Thread, 40 Male Thread Part, 41 1st contact part, 42 2nd contact part, 43a, 43b flat surface, 50 bottom, 51a, 51b flat surface, 100 exhaust passage, 101 bypass passage, 102 WG valve, 103 link mechanism, 103a, 103b plate.

Claims (4)

A rotor that has a female thread inside and rotates,
A shaft having a male threaded portion that meshes with the female threaded portion and converting the rotational motion of the rotor into a linear motion along the axial direction and outputting the shaft.
A closed-side regulating mechanism having a closed-side stopper and a first contact portion of the shaft that abuts on the closed-side stopper and restricting the movement of the shaft in the valve-closing direction, hitting the open-side stopper and the open-side stopper. An opening side regulating mechanism having a second contact portion of the shaft in contact and restricting the movement of the shaft in the valve opening direction, or a rotation stopper having a flat surface and the shaft in which the flat surface comes into contact with the flat surface. With a third contact portion of the shaft and a rotation regulating mechanism for regulating the rotation of the shaft around the axis.
The closed-side regulating mechanism, the open-side regulating mechanism, or the rotation-regulating mechanism is elastic in which , of the two components that abut each other, the component on the side that the shaft abuts is fixed by adhesion or insert molding. A valve-driven actuator characterized by being a body . When the closed side regulating mechanism is provided, the closed side stopper is provided at the output side tip of the female thread portion.
When the open side regulating mechanism is provided, the open side stopper is provided inside a boss located on the output side of the rotor and through which the shaft penetrates.
When provided with the rotation regulating mechanism, the rotating stopper valve drive actuator according to claim 1, wherein said shaft located on the output side of the rotor, characterized in that the Ru provided inside the boss penetrates. The valve drive actuator according to claim 1 or 2, wherein the elastic body is rubber. The valve drive actuator according to any one of claims 1 to 3.
A valve drive device including a valve driven by the valve drive actuator.

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