JP4992922B2 - Intake valve drive unit and intake valve device - Google Patents

Description

  The present invention relates to an intake valve drive unit used in an intake system of an internal combustion engine (hereinafter referred to as “engine”), and an intake valve device using the unit.

  As an intake valve device provided in an intake system of an engine, one that adjusts the flow of intake air on the combustion chamber side of the throttle valve is known. The purpose of using such a device is to create an intake flow called a tumble flow or swirl flow in the combustion chamber. As a result, stable combustion can be obtained even in a lean air-fuel mixture region, and as a result, it is possible to improve combustion efficiency (improve fuel efficiency) and improve exhaust components.

The structure of the intake valve device changes the passage area in the intake pipe by opening and closing the valve body.
By the way, in such an intake valve device, there is one in which a valve body is controlled by an intake valve drive unit. The intake valve drive unit includes a motor, and an output gear is driven by the motor from a worm gear attached to a rotation shaft of the motor via a helical gear. In this case, the rotation of the helical gear is held by the frictional force of the tooth surface of the worm gear, whereby the position of the output gear is held, and as a result, the position of the valve body is held.

  However, since the intake valve device is mounted on a vehicle, when the vibration generated in the intake valve device increases, the frictional force of the tooth surface of the worm gear decreases because the rotor inside the motor changes its position in the axial direction. Sometimes. In such a case, there is a possibility that the helical gear is rotated little by little, and as a result, it is difficult to maintain the position of the valve body. In addition, grease is generally applied to the tooth surface of the worm gear, but since the viscosity of the grease changes as the temperature of the engine room rises, this also causes a decrease in the frictional force on the tooth surface of the worm gear. To do.

  In order to solve this problem, there is an intake valve device that performs PWM energization to the motor. However, since torque is constantly generated in the motor shaft, there is a problem that the worm gear and the helical gear bite. In addition, the normal energization promotes the wear of the brush of the motor or increases the heat generation of the motor, which may shorten the life of the motor.

  Therefore, the present applicant has proposed a device that holds the position of the valve body using a permanent magnet (see Patent Document 1). In this apparatus, the position of the valve body is maintained by the contact and adsorption of the permanent magnet.

JP 2002-285852 A

  However, since the technique described in Patent Document 1 adsorbs the permanent magnets or the permanent magnet and the magnetic body, it cannot be denied that the permanent magnet or the magnetic body is easily damaged. As a result, there is a concern that the reliability of the intake valve drive unit, and hence the reliability of the intake valve device, may be lowered.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a highly reliable intake valve drive unit that reliably holds the position of the valve body.

  According to a first aspect of the present invention, there is provided an intake valve drive unit for opening and closing a valve body so as to change a passage area in an intake pipe of an engine. In this unit, the motor controls the opening and closing of the valve body. The transmission gear transmits the driving force of the motor, and the output gear is engaged with the transmission gear and attached to the valve shaft as the rotation shaft of the valve body.

  Here, particularly in the present invention, the suction portion is provided in the output gear, and moves around the valve shaft as the output gear rotates. On the other hand, the sucked part is provided corresponding to a predetermined position in the moving range of the sucking part. Thereby, when the suction part comes to the predetermined position, a suction force acts in a non-contact state with the sucked part.

  As described above, since a suction force acts between the suction portion and the portion to be sucked at the predetermined position, the position of the valve body can be reliably held in a state where the suction force is applied. Moreover, since this suction force acts in a non-contact state, it is possible to prevent damage to the suction part or the sucked part. As a result, the reliability of the intake valve drive unit can be improved.

  It is conceivable that the predetermined position where the suction force acts is two positions corresponding to the fully open position and the fully closed position of the valve body, as shown in claim 2. In this way, the valve body can be reliably held in the fully open position and the fully closed position.

  By the way, as shown in claim 3, the suction force acting between the suction portion and the suction target portion may act in the valve shaft direction at a predetermined position. In this case, a configuration in which the suction portion and the suction target portion are arranged side by side in the valve axis direction at a predetermined position is exemplified. Further, as shown in claim 4, the suction force may act in the radial direction at a predetermined position. In this case, the structure by which a suction part and a to-be-sucked part are arrange | positioned along with radial direction in a predetermined position is illustrated.

  If the suction force acts in the rotation direction (circumferential direction) of the output gear, the influence of the suction force on the drive of the output gear by the motor may increase. On the other hand, when the above-described configuration is adopted, the suction force acts in the axial direction and the radial direction perpendicular to the rotation direction, so that the influence of the suction force on the driving of the output gear can be suppressed.

  By the way, it is conceivable to configure at least one of the attracting part and the attracted part as a permanent magnet (claims 5 and 7). In the configuration in which the attraction portion on the output gear side is a permanent magnet, as shown in claim 6, magnetic detection means may be provided in correspondence with a specific position in the moving range of the attraction portion. Here, the magnetic detection means is embodied as a Hall IC, for example. If it does in this way, passage of an attraction part can be judged by a magnetic detection means, and rotation information on an output gear can be acquired using an attraction part.

Although the above description has been given as an invention of an intake valve drive unit, the present invention can also be realized as an invention of an intake valve device configured using the unit.
That is, the intake valve device changes a passage area in an intake pipe of an engine, and includes a valve body that changes the passage area of the intake pipe, a valve shaft that rotatably holds the valve body, and a valve body A motor for controlling opening / closing of the motor, a transmission gear for transmitting the driving force of the motor, an output gear meshed with the transmission gear and attached to the valve shaft, and provided in the output gear. A suction portion that moves around an axis, and a suctioned portion that is provided corresponding to the predetermined position so that a suction force acts in a non-contact state when the suction portion comes to a predetermined position in the movement range. It is characterized by.

  In such an intake valve device, the same effect as the intake valve drive unit is obtained. That is, since a suction force acts between the suction part and the suctioned part, the position of the valve body can be reliably held. Moreover, since this suction force acts in a non-contact state, it is possible to prevent damage to the suction part or the sucked part. As a result, the reliability of the intake valve device can be improved.

  In such an intake valve device, the configurations shown in claims 9 to 14 may be adopted as in the intake valve drive unit. If these configurations are employed, the same effects as those of the intake valve drive unit can be obtained.

1 is a schematic configuration diagram of an intake valve device according to an embodiment of the present invention. It is explanatory drawing which shows the periphery structure of an output gear. It is the III-III line schematic sectional drawing of Fig.2 (a). It is the IV-IV line schematic sectional drawing of Fig.2 (a).

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The intake valve device of the present embodiment constitutes a part of the intake pipe downstream of the throttle valve, changes the passage area of the intake pipe, and creates a tumble flow in the combustion chamber.

  FIG. 1 is a schematic plan view of an intake valve device 1 of the present embodiment. In FIG. 1, a part is cut out so that a cross section partially appears. As shown in FIG. 1, the intake valve device 1 includes an intake block 10 and an intake valve drive unit 20.

  The intake block 10 is fixed on an intake port of a cylinder head (not shown). That is, it constitutes a part of the intake pipe to the engine. Therefore, the intake block 10 has an intake passage 11 therein. The intake passage 11 is partitioned by a partition wall 12. Thereby, the intake passage 11 is constituted by a main passage 12a having a relatively large passage area and a sub passage 12b having a relatively small passage area.

  At this time, the valve body 13 closes the main passage 12a by being fully closed. The valve body 13 is formed of a plate-like metal member, and is screwed to the valve shaft 14 passing through the center of the intake passage 11 with a screw 15. The valve shaft 14 is rotatably supported with respect to the intake block 10 by a ball bearing 16 or the like. Thereby, the valve body 13 is opened and closed with the valve shaft 14 as a center by the rotational drive of the valve shaft 14. When the valve body 13 is fully opened, intake is performed to the combustion chamber via the main passage 12a and the sub passage 12b. When the valve body 13 is fully closed, intake to the combustion chamber is performed via the sub passage 12b. Is called. Thus, in the intake valve device 1, the passage area of the intake passage 11 can be changed by the valve body 13 in accordance with the operating state of the engine.

  The intake valve drive unit 20 is made of a resin housing 21 and has an outer shell. A motor 22 is disposed inside the housing 21. The output shaft 221 of the motor 22 extends leftward in FIG. Therefore, a driving force transmission unit 23 described later is disposed on the output shaft 221 side of the motor 22. On the other hand, a connector 24 is provided on the side opposite to the output shaft 221 (right side in FIG. 1). The connector 24 has a plurality of terminals 241. These terminals 241 include a terminal for supplying power to the motor 22 and a terminal for acquiring a signal from the Hall IC described later.

Here, the configuration of the driving force transmission unit 23 will be described.
The driving force transmission part 23 is mainly composed of various gears attached to the shaft part 25. In the portion where the shaft portion 25 is attached, the housing 21 is provided with an opening corresponding to one end side of the shaft portion 25. A resin cover 26 closes the opening, and the shaft portion 25 is fixed by the housing 21 and the cover 26.
The driving force transmission unit 23 includes a worm gear 231, a helical gear (not shown) provided on the back side of the worm gear 231, a coupling unit 232, a transmission gear 233, and an output gear 244.

  The worm gear 231 is attached to the output shaft 221 of the motor 22. A helical gear is provided corresponding to the worm gear 231. This helical gear is rotatably supported by the shaft portion 25. Although the configurations of the worm gear 231 and the helical gear are well known, they will be omitted, but with this configuration, the driving force extracted from the output shaft 221 of the motor 22 is extracted as turning power centered on the shaft portion 25.

  The connecting portion 232 is a cylindrical member, and connects the helical gear and the transmission gear 233. The transmission gear 233 is rotatably supported by the shaft portion 25 as in the helical gear. As a result, the transmission gear 233 rotates in conjunction with the helical gear via the connecting portion 232. The center of the connecting portion 232 in the axial direction is a cushion made of an elastomer. Therefore, the axial twist generated in the connecting portion 232 is alleviated.

  The output gear 244 meshes with the transmission gear 233. The output gear 244 is fixed to the valve shaft 14 of the intake block 10 with a nut 27. Thereby, the rotation of the output gear 234 appears as the rotation of the valve shaft 14.

Next, the peripheral configuration of the output gear 234, which is a characteristic part of this embodiment, will be described.
2A and 2B are schematic plane views of the output gear 234 and are schematic views showing only a characteristic configuration. 3 is a schematic cross-sectional view taken along line III-III in FIG. 2A, and FIG. 4 is a schematic cross-sectional view taken along line IV-IV in FIG.

  As shown in FIGS. 2A and 2B, the output gear 234 has a central portion fixed to the valve shaft 14 (see FIGS. 3 and 4) with a nut 27. Further, the output gear 234 has a gear part 31 whose teeth are cut along an arc and a suction part 32 provided on the opposite side to the gear part 31 in the radial direction. A permanent magnet 321 is embedded in the central portion of the suction part 32. In this embodiment, the permanent magnet 321 has a magnetic pole in the direction of the valve shaft 14 and generates magnetic lines of force in that direction.

  The output gear 234 can be rotated clockwise from the position shown in FIG. 2A to the position shown in FIG. 2B by the transmission gear 233 that meshes with the gear portion 31 as described above. Further, it can be rotated counterclockwise from the position shown in FIG. 2B to the position shown in FIG. That is, the output gear 234 rotates in the range of 90 degrees in this embodiment. When the output gear 234 reaches the position of FIG. 2A, the valve body 13 is fully closed, and when the output gear 234 reaches the position of FIG. 2B, the valve body 13 is fully opened. If attention is paid to the suction part 32, the suction part 32 has a range of movement from the “12 o'clock” position to the “3 o'clock” position.

  Then, suctioned portions 41 and 42 are provided corresponding to the positions of “12 o'clock” and “3 o'clock”. As shown in FIG. 3, one sucked portion 41 has a U-shaped cross section that opens in the radial direction, and the suction portion 32 can pass through the inside. The same applies to the other suction target 42. The attracted portions 41 and 42 are made of a magnetic material. Thereby, in the fully closed state of the valve body 13 in which the suction part 32 comes to the “12 o'clock” position and the fully opened state of the valve body 13 in which the suction part 32 comes to the “3 o'clock” position, the valve shaft 14 is contactless. Adsorption force in the direction acts.

  A Hall IC 51 is disposed at a specific position in the moving range of the suction unit 32. In the Hall IC 51, as shown in FIG. 4, the sensor portion 511 and the lead portion 512 are molded with resin. The Hall IC 51 is arranged so that the sensor unit 511 is aligned with the permanent magnet 321 embedded in the suction unit 32 in the valve shaft 14 direction at a specific position.

  In this embodiment, the valve body 13 forms a “valve body”, the valve shaft 14 forms a “valve shaft”, the motor 22 forms a “motor”, and the transmission gear 233 forms a “transmission gear”. The output gear 234 constitutes an “output gear”. Further, the suction part 32 in this embodiment constitutes a “suction part”, and the sucked parts 41 and 42 constitute a “sucked part”. Furthermore, the Hall IC 51 in this embodiment constitutes “magnetic detection means”.

Next, the effect exhibited by the intake valve device 1 of the present embodiment will be described.
The output gear 234 is rotated from the position shown in FIG. 2A to the position shown in FIG. 2B by the transmission gear 233 that meshes with the gear portion 31 as described above. That is, the output gear 234 rotates in the range of 90 degrees in this embodiment. If attention is paid to the suction part 32, the suction part 32 has a range of movement from the “12 o'clock” position to the “3 o'clock” position. Corresponding to each of these positions, suctioned portions 41 and 42 are provided. Here, a permanent magnet 321 is embedded in the attracting part 32, and the attracted parts 41 and 42 are made of a magnetic material. Thereby, at the position of “12 o'clock” and “3 o'clock”, a suction force in the direction of the valve shaft 14 is applied without contact.

  In this way, at the “12 o'clock” and “3 o'clock” positions, a suction force acts between the suction portion 32 and the sucked portions 41 and 42. The position can be reliably held. Moreover, since this suction force acts in a non-contact state, damage to the suction part 32 or the sucked parts 41 and 42 can be prevented. As a result, it is possible to improve the reliability of the intake valve drive unit 20 and thus the reliability of the intake valve device 1.

  In this embodiment, the positions of “12 o'clock” and “3 o'clock” at which the suction force acts correspond to the fully closed state and the fully open state of the valve body 13, respectively. Thereby, a valve body can be reliably hold | maintained in a fully open position and a fully closed position.

  By the way, if the suction force is applied in the rotation direction (circumferential direction) of the output gear 234, the influence of the suction force on the driving of the output gear 234 by the motor 22 may be increased. In this respect, in the present embodiment, the permanent magnet 321 has a magnetic pole in the valve axis direction. As a result, the suction force acting between the suction part 32 and the sucked parts 41 and 42 acts in the valve shaft direction. As a result, the influence of the suction force on the driving of the output gear 234 can be suppressed.

  Furthermore, in this embodiment, the Hall IC 51 is provided in correspondence with a specific position in the movement range of the suction unit 32. Thereby, the passage of the suction part 32 can be determined by the Hall IC 51, and the rotation information of the output gear 234 can be acquired using the suction part 32.

  As described above, the present invention is not limited to the above embodiment, and can be implemented in various forms without departing from the spirit of the invention.

  (A) In the above embodiment, the output gear 234 rotates in the range of 90 degrees, and the fully closed state and the fully open state of the valve body 13 are created. In this regard, the rotation range of the output gear is not limited to 90 degrees. For example, a range of 85 degrees may be rotated. Further, for example, a range of 95 degrees may be rotated.

  (B) In the embodiment described above, the magnetic pole of the permanent magnet 321 is provided in the valve axis direction so that an attractive force in the valve axis direction acts between the suction part 32 and the sucked parts 41 and 42. On the other hand, you may comprise so that radial suction force may act between a suction part and a to-be-sucked part. Even if it does in this way, the influence of the attraction | suction force with respect to the drive of the output gear 234 can be suppressed compared with the structure to which an attraction | suction force acts in the rotation direction (circumferential direction) of the output gear 234.

  (C) In the above embodiment, the permanent magnet 321 is embedded in the attraction portion 32. On the other hand, it is also conceivable that the attracted parts 41 and 42 are made of permanent magnets together with or instead of the attracting part 32.

  1: Intake valve device, 10: Intake block, 11: Intake passage, 12: Partition wall, 12a: Main passage, 12b: Sub passage, 13: Valve body, 14: Valve shaft, 15: Screw, 16: Ball bearing , 20: intake valve drive unit, 21: housing, 22: motor, 23: driving force transmission part, 24: connector, 25: shaft part, 26: cover, 27: nut, 31: gear part, 32: suction part 41: suctioned part, 221: output shaft, 231: worm gear, 232: coupling part, 233: transmission gear, 234: output gear, 241: terminal, 244: output gear, 321: permanent magnet, 51: Hall IC ( Magnetic detection means), 511: sensor part, 512: lead part

Claims (14)

An intake valve drive unit for opening and closing a valve body so as to change a passage area in an intake pipe of an engine,
A motor for controlling opening and closing of the valve body;
A transmission gear for transmitting the driving force of the motor;
An output gear meshed with the transmission gear and attached to a valve shaft as a rotation shaft of the valve body;
A suction part provided on the output gear and moving around the valve shaft as the output gear rotates;
A suctioned portion provided corresponding to the predetermined position so that a suction force acts in a non-contact state when the suction portion comes to a predetermined position in the movement range;
An intake valve drive unit characterized by comprising: The intake valve drive unit according to claim 1,
The intake valve drive unit according to claim 1, wherein the predetermined positions are two positions corresponding to a fully open position and a fully closed position of the valve body. In the intake valve drive unit according to claim 1 or 2,
The intake valve drive unit according to claim 1, wherein the suction force acts in a valve shaft direction at the predetermined position. In the intake valve drive unit according to any one of claims 1 to 3,
The intake valve drive unit, wherein the suction force acts in a radial direction at the predetermined position. In the intake valve drive unit according to any one of claims 1 to 4,
The suction valve drive unit, wherein the suction part is configured using a permanent magnet. In the intake valve drive unit according to claim 5,
An intake valve drive unit, comprising: a magnetic detection unit disposed in correspondence with a specific position in the moving range of the suction unit. In the intake valve drive unit according to any one of claims 1 to 6,
The intake valve drive unit according to claim 1, wherein the sucked portion is configured using a permanent magnet. An intake valve device for changing a passage area in an intake pipe of an engine,
A valve body that changes a passage area of the intake pipe;
A valve shaft that rotatably holds the valve body;
A motor for controlling opening and closing of the valve body;
A transmission gear for transmitting the driving force of the motor;
An output gear meshing with the transmission gear and attached to the valve shaft;
A suction part provided on the output gear and moving around the valve shaft as the output gear rotates;
A suctioned portion provided corresponding to the predetermined position so that a suction force in the valve shaft direction acts in a non-contact state when the suction portion comes to a predetermined position in the movement range;
An intake valve device comprising: The intake valve device according to claim 8 ,
The intake valve device, wherein the predetermined positions are two positions corresponding to a fully open position and a fully closed position of the valve body. The intake valve device according to claim 8 or 9 ,
The intake valve device, wherein the suction force acts in a valve shaft direction at the predetermined position. The intake valve device according to any one of claims 8 to 10 ,
The intake valve device, wherein the suction force acts in a radial direction at the predetermined position. The intake valve device according to any one of claims 8 to 11 ,
The suction valve device is configured by using a permanent magnet. The intake valve device according to claim 12 ,
An intake valve device comprising magnetic detection means arranged in correspondence with a specific position in the moving range of the suction portion. The intake valve device according to any one of claims 8 to 13 ,
The intake valve device, wherein the sucked part is configured using a permanent magnet.

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