JP2007068378A - Motor actuator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To restrain flattering of an intake flow control valve by vehicle vibration or engine vibration. <P>SOLUTION: A coil spring 10 is disposed relative to a worm gear 51 for applying a preload which overcomes reaction caused by vehicle vibration or engine vibration as a factor, between a front end surface of a yoke housing 41 of an electric motor 6 and a motor-side end surface of the worm gear 51. The coil spring 10 is disposed relative to a worm gear 51 for applying a preload which overcomes reaction caused by vehicle vibration or engine vibration as a factor, between a housing-side end surface of a motor shaft 7 of the electric motor 6 and a bottom wall surface of the housing 9. This makes it difficult for a worm gear 51 to rattle in the thrust direction within a clearance between the worm gear 51 and a helical gear engaging with the worm gear 51. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  According to the present invention, the gap formed between the tooth surfaces of the first gear driven by the motor and the second gear meshing with the first gear is narrowed to suppress backlash of the first and second gears due to vibration. The present invention relates to an intake vortex generator for an internal combustion engine provided with the motor actuator.

[Conventional technology]
Conventionally, in an intake system of an internal combustion engine, an intake flow control valve has been provided in an intake pipe downstream of the throttle valve in the direction of intake air flow so that the internal combustion engine can be started, idle, or traveling in a vehicle. The intake flow control valve is driven by a motor, the main passage of the intake passage formed in the intake pipe is closed, and only a part of the intake passage (portion near the wall of the passage) is opened, so that the intake port of the internal combustion engine In the vicinity of the engine, an intake air drift occurs, causing vortex flow in the intake air flowing into the combustion chamber from the intake port of the internal combustion engine, promoting combustion of the air-fuel mixture in the combustion chamber of the internal combustion engine, improving emissions and improving fuel efficiency. 2. Description of the Related Art An intake vortex generator for an internal combustion engine that is designed is known (see, for example, Patent Documents 1 and 2).

  As shown in FIGS. 8 and 9, this type of intake vortex generator for an internal combustion engine includes a valve drive device (motor actuator) 102 that drives the intake flow control valve 101 to close (or open). Yes. The valve driving device 102 includes an electric motor 104 that generates a driving force for driving a drive shaft 103 that holds and fixes the intake flow control valve 101, a worm gear 106 that is fixed to the motor shaft 105 of the electric motor 104, and the worm gear 106. And a gear reduction mechanism having a helical gear 107 and the like meshing with each other. The gear reduction mechanism is a reduction function that reduces the rotational speed of the motor shaft 105 of the electric motor 104 to a predetermined reduction ratio, and a power transmission that transmits the driving force of the electric motor 104 to the drive shaft 103 of the intake flow control valve 101. Combines functionality. Further, since the valve drive device 102 uses the worm gear 106 and the helical gear 107 as a part of the gear reduction mechanism, when the operation of the intake flow control valve 101 is stopped (for example, when the valve is fully opened or when the valve is fully closed), A self-locking effect that holds the intake flow control valve 101 at a predetermined operation stop position can be obtained.

[Conventional technical problems]
However, in a conventional intake vortex generator for an internal combustion engine, vehicle vibrations and engine vibrations are transmitted to a housing that internally forms a motor housing hole and a gear chamber, and the vibrations act in the thrust direction of the electric motor 104 and the worm gear 106. Then, since there is a backlash between the end surface portion of the electric motor 104 and the inner wall surface of the housing, the worm gear 106 will play back in the thrust direction in the gap (backlash) between the tooth surfaces of the worm gear 106 and the helical gear 107. There is a problem that the self-locking effect is lost, and the helical gear 107 and the intake flow control valve 101 flutter inside the intake passage 110 formed in the intake pipe 109.

  Further, in a conventional intake vortex generator for an internal combustion engine, when the worm gear 106 rattles in the thrust direction within the gap between the tooth surfaces of the worm gear 106 and the helical gear 107 due to vehicle vibration or engine vibration, the tooth surface of the worm gear 106 Since the tooth surface of the helical gear 107 repeatedly collides or frictions, the tooth surface of the worm gear 106 or the tooth surface of the helical gear 107 may be abnormally worn. In this case, when the intake flow control valve 101 is driven to close (or open), even if the worm gear 106 is rotationally driven by the electric motor 104, the worm gear 106 is not engaged with the worm gear 106 and the helical gear 107 due to poor meshing. There arises a problem that the helical gear 107 idles or the worm gear 106 and the helical gear 107 are engaged with each other, thereby losing the power transmission function of the gear reduction mechanism and the performance of the valve driving device 102 being impaired.

Further, when the operation of the intake flow control valve 101 is stopped, the self-lock effect for holding the intake flow control valve 101 at a predetermined operation stop position (for example, the fully closed position or the fully open position) is lost, and the intake flow control valve 101 is inhaled. When fluttering in the passage 110, the opening area of the main passage of the intake passage 110 formed in the intake pipe 109 increases or decreases, so that the amount of intake air taken into the combustion chamber of the internal combustion engine changes. End up. Since the engine speed fluctuates due to the change in the intake air amount, there arises a problem that the drivability of the vehicle is deteriorated.
JP 2001-248449 A (page 1-7, FIGS. 1-8) JP 2002-256874 A (page 1-6, FIGS. 1 to 9)

  The objective of this invention is providing the motor actuator which can suppress the flapping of the moving body by a vibration at the time of the operation | movement stop of a moving body. It is another object of the present invention to provide a motor actuator that can maintain the self-locking effect of the moving body and the second gear.

  According to the first aspect of the present invention, the tooth surface of the first gear and the tooth surface of the second gear are pressed against the first gear driven by the motor or the second gear meshing with the first gear. Even if the vibration is transmitted to any of the motor, the first gear, and the second gear, the first gear is provided by applying a pressure application means for applying a pressure that overcomes the reaction force caused by the vibration in the direction. The first gear or the second gear is less likely to rattle within the gap between the tooth surfaces of the second gear and the second gear. As a result, the second gear installed on the moving body side is less likely to swing with respect to the first gear, so that it is possible to suppress fluttering of the moving body due to vibration when the operation of the moving body is stopped. As a result, the self-locking effect of the moving body and the second gear can be maintained, so that abnormal wear between the tooth surface of the first gear and the tooth surface of the second gear can be prevented. Moreover, since the performance degradation of the power transmission mechanism including the first gear and the second gear can be suppressed, the performance as a motor actuator is not impaired.

  Here, as the pressurizing force application means, a spring for applying a prestressing force (pressurized load, preload) to overcome the reaction force caused by vibration in the thrust direction of the first gear with respect to the first gear, An elastically deformable member such as a leaf spring, washer, or rubber material may be used. Further, as the pressurizing force applying means, a spring, a plate for applying a pressurizing force (pressurizing load, preload) to overcome the reaction force caused by vibration in the rotation direction of the second gear with respect to the second gear An elastically deformable member such as a spring, washer or rubber material may be used.

  According to the second aspect of the present invention, the worm gear fixed to the output shaft of the motor or the helical gear that meshes with the worm gear and rotates in a direction that presses the tooth surface of the worm gear and the tooth surface of the helical gear. Even if vibration is transmitted to either the motor or the worm gear, the worm gear in the gap between the tooth surfaces of the worm gear and the helical gear is provided. However, it becomes difficult to play in the axial direction (thrust direction) of the output shaft of the motor. As a result, the helical gear installed on the moving body is less likely to swing with respect to the worm gear installed on the motor side, so that it is possible to suppress the flapping of the moving body due to vibration when the operation of the moving body is stopped. Thus, the effect of the invention described in claim 1 can be obtained.

  According to the third aspect of the present invention, vibration is generated in a direction in which the helical gear tooth surface and the worm gear tooth surface are pressed against the helical gear fixed to the output shaft of the motor or the worm gear rotating in mesh with the helical gear. Even if vibration is transmitted to either the motor or the helical gear, the helical gear is installed in the clearance between the tooth surfaces of the helical gear and the worm gear. However, it becomes difficult to play in the axial direction (thrust direction) of the output shaft of the motor. As a result, the worm gear installed on the moving body side is less likely to swing with respect to the helical gear installed on the motor side, so that it is possible to suppress fluttering of the moving body due to vibration when the operation of the moving body is stopped. Thus, the effect of the invention described in claim 1 can be obtained.

  According to invention of Claim 4, the motor is accommodated inside the motor accommodation hole of a housing. The motor output shaft may be rotatably supported on the bearing portion of the housing via an elastic member that can be elastically deformed in the radial direction of the motor output shaft. In this case, even if the vibration is transmitted to the motor, the vibration of the output shaft of the motor is attenuated by the elastic member, so that the first gear or the second gear moves in the radial direction (radial direction) of the output shaft of the motor. It becomes difficult to play. Thereby, the 1st gear installed in the motor side becomes difficult to shake in the radial direction.

  According to a fifth aspect of the present invention, the moving body has a valve shaft that is drivingly connected to the power transmission mechanism, and is a valve that rotates integrally with the valve shaft. Note that this valve may be used as a flow rate control valve for controlling the flow rate of air flowing in the air passage of the housing. The flow control valve may be used as a throttle valve, an idle rotation speed control valve, an intake control valve, or the like that adjusts the amount of intake air taken into the combustion chamber of the internal combustion engine. The flow control valve may be used as an exhaust control valve that adjusts the flow rate of exhaust gas discharged from the combustion chamber of the internal combustion engine. Further, the flow control valve may be used as an exhaust gas recirculation amount control valve for adjusting an exhaust gas recirculation amount for recirculating a part of the exhaust gas of the internal combustion engine to the intake side.

  According to the sixth aspect of the present invention, the moving body opens and closes a part of the intake passage formed in the housing, so that the intake air that causes a vortex in the air flowing from the intake passage into the combustion chamber of the internal combustion engine is generated. It may be used as a flow control valve. Then, this intake flow control valve may be used as a swirl flow control valve for generating a lateral vortex in the air flowing into the combustion chamber from the intake passage. Further, the intake flow control valve may be used as a tumble flow control valve that generates a vertical vortex in the air flowing into the combustion chamber from the intake passage.

  According to the seventh aspect of the present invention, the moving body is configured such that the passage length or the opening area of the intake passage formed in the housing corresponding to the operating state of the internal combustion engine (for example, the engine rotation speed) is varied, The present invention may be applied to a variable intake device that improves the output of an internal combustion engine, and may be used as a variable intake valve that changes the passage length or opening area of the intake passage by opening and closing the intake passage formed in the housing. Further, the moving body may be a rotating body that has a drive shaft that is drivingly connected to the power transmission mechanism and that performs a rotational motion integrally with the drive shaft. In addition, a movement direction conversion mechanism that converts the rotational movement of the speed reduction mechanism into a linear movement is interposed between the power transmission mechanism and the moving body, and the moving body has a drive shaft that is drivingly connected to the movement direction conversion mechanism. However, it may be a moving body such as a valve that linearly moves integrally with the drive shaft.

  The best mode for carrying out the present invention is driven by a motor for the purpose of suppressing flapping of the moving body due to vehicle vibration or engine vibration, for example, when the operation of the moving body (rotating body such as a valve) is stopped. Applying a pressure to overcome the reaction force caused by vibration in the direction of pressing the tooth surface of the first gear and the tooth surface of the second gear against the first gear or the second gear meshing with the first gear This is realized by providing a pressure applying means (an elastically deformable member such as a spring, a leaf spring, a washer, or a rubber material).

[Configuration of Example 1]
1 to 3 show a first embodiment of the present invention, FIG. 1 is a diagram showing a schematic configuration of an intake system for an internal combustion engine, and FIG. 2 is a schematic configuration of an intake vortex generator for an internal combustion engine. FIG. 3 shows the overall structure of the motor actuator.

  An intake system for an internal combustion engine (intake device for an internal combustion engine) of this embodiment is provided in an intake system of an internal combustion engine (hereinafter referred to as an engine) 1 mounted on a vehicle such as an automobile. An engine intake pipe 11 and an engine exhaust pipe (not shown) are connected to the engine 1. Here, a piston 13 that reciprocates in the vertical direction in the figure is slidably supported on the cylinder 12 of the engine 1. A combustion chamber 14 defined by the cylinder 12 and the cylinder head is formed above the piston 13 in the figure. A fuel injection valve (injector) 15 is installed in the cylinder head at the top of the combustion chamber 14. In addition, an intake port 17 that is opened and closed by an intake valve 16 and an exhaust port 19 that is opened and closed by an exhaust valve 18 are formed in the cylinder head.

  The engine intake pipe 11 includes an air cleaner 21, a throttle body 22, an intake manifold 23, and the like, and forms an intake passage that communicates with the intake port 17 of the engine 1 inside. The engine intake pipe 11 is provided with a resonator (silencer) 24, a slot valve 25 and an intake variable valve 26. The throttle valve 25 is an air flow control valve that has a valve shaft that is rotatably supported by the throttle body 22 and performs a rotational motion integrally with the valve shaft. The throttle opening control device for an internal combustion engine provided with the throttle valve 25 drives the electric motor in accordance with the amount of depression of the driver (driver) (accelerator operation amount of the driver), and adjusts the rotation angle of the throttle valve 25. The system controls the output of the engine 1 (engine rotational speed or engine output shaft torque) by controlling the amount of intake air taken into the combustion chamber 14 of the engine 1 by changing the corresponding throttle opening. .

  The intake variable valve 26 has a valve shaft that is rotatably supported by the intake manifold 23. The intake variable valve 26 rotates in unison with the valve shaft, so that the intake passage length (or intake passage cross-sectional area) of the intake manifold 23 is obtained. ) Is an air flow path opening / closing control valve that switches between two stages. The variable intake control device for an internal combustion engine provided with the intake variable valve 26 drives the electric motor in response to the engine rotational speed, the engine load, etc., and controls the intake variable valve 26 to open / close, so that the inertia of the intake air is obtained. This is a system that improves the output of the engine 1 (engine output shaft torque) by giving a supercharging effect or a resonance supercharging effect. Of the intake passages formed in the intake manifold 23, the intake passage 27 used when the engine rotational speed is in the low / medium speed rotational region is more than the intake passage 28 used when the engine rotational speed is in the high speed rotational region. The intake passage is formed to have a long length.

  Here, the internal combustion engine intake system of the present embodiment is capable of generating a lateral intake vortex flow (swirl flow) for promoting combustion of fuel or air-fuel mixture in the combustion chamber 14 of the engine 1. An engine intake vortex generator is provided. This includes a cylindrical housing 2 provided integrally with the cylinder head of the engine 1 and an intake flow control valve 3 accommodated in the housing 2 so as to be openable and closable inside the housing 2 (that is, inside the intake port 17 of the engine 1). And a coil spring (valve urging means) 4 that urges the intake flow control valve 3 in the fully open direction (or the fully closed direction). A motor actuator (valve driving device) 5 that drives the intake flow control valve 3 to close (or opens) includes an electric motor 6 that is driven by electric power, and a motor shaft (output shaft) 7 of the electric motor 6. Is constituted by a power transmission mechanism or the like for transmitting the rotational motion of the motor to the intake flow control valve 3. The intake system for the internal combustion engine includes an engine control unit (hereinafter referred to as ECU: not shown) that electronically controls the electric motor 6 that is a power source of the intake flow control valve 3 based on the operating state of the engine 1. Yes.

  Here, the ECU is provided with a microcomputer having a well-known structure configured to include functions such as a CPU for performing control processing and arithmetic processing, various programs, and a storage device (memory such as ROM and RAM) for storing data. It has been. This ECU controls the rotational motion of the electric motor 6 by adjusting the power supplied to the electric motor 6 based on a control program stored in the memory when the ignition switch is turned on (IG / ON). Control unit. The ECU detects the engine rotation speed by a sensor signal such as a crank angle sensor (not shown) at the time of engine start or idling operation, and supplies electric power to the electric motor 6 according to the engine rotation speed to thereby control the intake air flow control valve. The intake flow control valve 3 is driven to close so that 3 is fully closed. Further, the ECU detects the engine rotation speed during steady operation of the engine 1 and supplies electric power to the electric motor 6 according to the engine rotation speed to control the rotation angle (valve opening) of the intake flow control valve 3. To do. For example, the intake flow control valve 3 is driven to open so that the intake flow control valve 3 is in a half-open state. Alternatively, the intake flow control valve 3 may be driven to open so that the intake flow control valve 3 is fully opened.

  The inside of the housing 2, that is, the intake port 17 of the engine 1 is airtightly divided into a first air flow path (swirl port) 31 and a second air flow path (main port) 32 by a partition wall portion 29. The swirl port 31 is provided on one side of the intake port 17 of the engine 1 and generates an intake vortex flow in the combustion chamber 14 of the engine 1. The main port 32 is provided on the lower side in the drawing than the swirl port 31 in the intake port 17 of the engine 1. The housing 2 may be formed integrally with the cylinder head of the engine 1 or may be coupled to the cylinder head of the engine 1 after being manufactured separately from the cylinder head of the engine 1.

  The intake flow control valve 3 is a swirl flow control valve that generates an intake vortex flow (swirl flow) in the combustion chamber 14 by controlling the opening degree of the main port 32 and actively flowing an air flow in the swirl port 31. is there. The intake flow control valve 3 is fully closed by the driving force (motor output shaft torque) of the electric motor 6 at the time of engine start or idle operation. Further, the intake flow control valve 3 is in a half-open state by the driving force (motor output shaft torque) of the electric motor 6 when the engine 1 is in a low speed rotation range (engine speed is about 2000 rpm, for example). Further, the intake flow control valve 3 is fully opened by the urging force (spring force, torsional elastic force) of the coil spring 4 when the engine 1 is in the middle speed / high speed rotation range (engine speed is, for example, 2500 rpm or more). Become. The intake flow control valve 3 has a valve shaft (drive shaft) 33 that is drivingly connected to the output portion of the power transmission mechanism, and is a moving body (rotary body) that performs a rotational motion integrally with the valve shaft 33. is there. Note that both end portions of the valve shaft 33 in the axial direction are rotatably supported by a valve bearing portion 35 of the housing 2 via ball bearings 34.

  The electric motor 6 employs a direct current (DC) motor that is energized and controlled by the ECU. The electric motor 6 is provided so as to protrude from the front end surface of the yoke housing 41 having a cylindrical portion to one side in the rotational axis direction (rotational center axis direction of the motor shaft 7; hereinafter referred to as the axial direction or the thrust direction). This is a DC motor with a brush composed of a rotor (armature) integrated with the motor shaft 7, a stator (field) disposed opposite to the outer peripheral side of the rotor, and the like. The rotor is provided with a rotor core (armature core) around which an armature coil (armature winding) is wound, a commutator electrically connected to the armature coil, and the like. The stator is provided with a yoke housing 41 and a permanent magnet held on the inner peripheral surface of the yoke housing 41. Further, a brush for supplying power to the armature coil is in sliding contact with the outer peripheral surface of the commutator. Note that a brushless DC motor or an alternating current (AC) motor such as a three-phase induction motor may be used instead of the brushed direct current (DC) motor.

  In the electric motor 6, the yoke housing 41 is fastened and fixed to the housing 9 using fastening screws or the like. In the electric motor 6, the outer peripheral surface of the cylindrical portion of the yoke housing 41 is in close contact with the inner peripheral surface of the housing (motor case) 9 coupled to the side wall surface of the housing 2. It is housed and held inside. Also, a motor connector 43 provided so as to protrude from the rear end surface of the housing 9 to the other side in the axial direction is a terminal (external connection terminal, motor) that is electrically connected to the armature coil via a brush and a commutator. Power supply terminal) 44 is held. The terminal 44 of the electric motor 6 is electrically connected to a battery mounted on the vehicle via a motor drive circuit electronically controlled by the ECU.

  Both end portions in the axial direction of the motor shaft 7 are provided so as to protrude from both end surfaces of the rotor core. A front side end portion of the motor shaft 7 in the axial direction is provided so as to protrude from the front end surface of the yoke housing 41 to one side in the axial direction, and an annular shape is formed on the cylindrical bearing portion of the yoke housing 41 of the electric motor 6. The rubber-based elastic body (elastic member, rubber member) 45 is rotatably supported. The axially rear end portion of the motor shaft 7 has an annular rubber-based elastic body (elasticity) on a cylindrical bearing portion of an end frame (motor housing, end surface portion) 46 coupled to the yoke housing 41 of the electric motor 6. (Member, rubber member) 47 is supported rotatably.

  The power transmission mechanism is configured by a gear reduction mechanism that reduces the rotational speed of the motor shaft 7 of the electric motor 6 so as to be a predetermined reduction ratio. The gear reduction mechanism is disposed on the same axis as the worm gear (first gear) 51 fixed to the motor shaft 7 of the electric motor 6, the helical gear (second gear) 52 that meshes with the worm gear 51, and the helical gear 52. Output spur gear 53. Between the helical gear 52 and the output spur gear 53, an impact absorbing member (described later) that rotates together with the gears 52 and 53 is disposed.

  Further, the helical gear 52 and the output spur gear 53 are rotatably supported on the outer periphery of a shaft 54 arranged perpendicular to the axial direction of the motor shaft 7 constituting the worm gear shaft. Both end portions of the shaft 54 are press-fitted and fixed to a housing 9 that forms a gear chamber 55 that accommodates a gear reduction mechanism therein. The shock absorbing member includes first and second plates 56 and 57, an elastic member (rubber material) 59, and the like. In the case where the transmission of torque acts shockfully, the impact absorbing member, for example, at the moment when the intake flow control valve 3 is fixed at the fully closed position, is caused by the torsional action that the elastic member 59 is deformed, so that the worm gear 51 It has the function of relaxing the impact load transmitted to the worm gear 51 and preventing the worm gear 51 from being tightened.

  Next, between the output spur gear 53 and the valve shaft 33 of the intake flow control valve 3, an output portion of a power transmission mechanism (a gear reduction mechanism in this embodiment) is disposed. The output section includes an input spar gear 61 that meshes with the output spar gear 53, a third plate 62 that contacts a cushion (rubber material) accommodated in the input spar gear 61, and a fourth plate that engages with one end of the coil spring 4. 63 etc. The third plate 62 drives and connects the input spur gear 61 and the valve shaft 33 of the intake flow control valve 3 via a cushion. A fitting hole is formed in the third plate 62 at the axial end of the valve shaft 33 of the intake flow control valve 3. In addition, a two-surface width portion that fits into the fitting hole of the third plate 62 is formed at the axial end of the valve shaft 33 of the intake flow control valve 3. This two-surface width portion is a portion that prevents relative rotation between the valve shaft 33 and the third plate 62.

  Here, the output portion of the gear reduction mechanism fixes the input spur gear 61 that is drivingly connected to the valve shaft 33 of the intake flow control valve 3 to the valve shaft 33 of the intake flow control valve 3, and is rotatable together with the valve shaft 33. By connecting the third plate 62 with the coil spring 4, for example, when abnormal pressure caused by abnormal combustion such as backfire occurs, the coil is resisted against the impact load due to the abnormal pressure applied to the intake flow control valve 3. By bending the spring 4, the input spur gear 61 and the motor side gear reduction mechanism can be separated. Thereby, the intake flow control valve 3 integrated with the valve shaft 33 can be rotated from the fully closed state to the fully open side in accordance with the abnormal load received in the fully closed state, that is, the impact load of the abnormal pressure. For this reason, the abnormal load received in the fully closed state is alleviated by releasing the abnormal pressure.

  Here, the intake vortex generator for an internal combustion engine of the present embodiment converts the rotation angle (valve opening) of the intake flow control valve 3 into an electrical signal (valve opening signal), and the intake flow control valve 3 is fully closed. A non-contact type valve opening degree detection device that outputs to the ECU whether the intake flow control valve 3 is fixed at the fully open position or how much the intake flow control valve 3 is open. . As shown in FIG. 2, this valve opening degree detection device is a permanent magnet (magnet) 64 provided on an input spur gear 61 fixed to the valve shaft 33 of the intake flow control valve 3, and a magnet together with the magnet 64. It is comprised by the valve opening degree sensor etc. which form a circuit.

  The valve opening sensor is configured to include a pair of yokes (magnetic bodies) magnetized by the magnet 64 and opposed to the magnet 64, and a Hall IC 65 disposed in a magnetic detection gap formed between the yokes. ing. The Hall IC 65 is an IC (integrated circuit) in which a Hall element (non-contact type magnetic detection element) and an amplifier circuit are integrated, and the magnetic flux density passing through the magnetic detection gap (the magnetic flux density interlinked with the Hall IC 65). ) Is output. Further, reference numeral 66 in FIG. 2 denotes a fully open stopper that restricts the intake flow control valve 3 at the fully open position.

  Here, in the motor actuator 5 of this embodiment, as shown in FIG. 3, vehicle vibrations and engine vibrations are transmitted from the cylinder head of the engine 1 to the housing 9, and the vibrations inside the motor housing holes 42 of the housing 9. When the electric motor 6 is held and fixed in the thrust direction, a gap is formed between the end frame 46 of the electric motor 6 and the bottom wall surface of the housing 9. Therefore, the electric motor 6 is fixed to the motor shaft 7 of the electric motor 6. The worm gear 51 rattles in the thrust direction within the gap between the tooth surfaces of the worm gear 51 and the helical gear 52 (backlash), loses the self-locking effect, and the helical gear 52 and the intake flow control valve 3 are in the main port 32. There was a problem of flapping.

  Therefore, in the motor actuator 5 of the intake vortex generator for an internal combustion engine of the present embodiment, generation of backlash in the thrust direction of the motor shaft 7 of the electric motor 6 and the worm gear 51 is prevented, and fluttering of the intake flow control valve 3 is suppressed. For the purpose, a coil spring (tension spring) 10 is disposed between the end frame 46 of the electric motor 6 and the bottom wall surface of the housing 9. The coil spring 10 presses the end frame 46 of the electric motor 6 against one side (the upper side in the drawing) of the motor shaft 7 of the electric motor 6 so that the tooth surface of the worm gear 51 is against the worm gear 51. It functions as a pressure application means for applying a pressure that overcomes a reaction force caused by vehicle vibration or engine vibration in the direction of pressing against the tooth surface of the helical gear 52 (on one side in the thrust direction of the worm gear 51 (upper side in the drawing)).

[Operation of Example 1]
Next, the operation of the intake vortex generator for an internal combustion engine according to this embodiment will be briefly described with reference to FIGS.

  The ECU energizes the armature coil built in the electric motor 6 so that the intake flow control valve 3 is fully closed when the engine is started or idling. When the armature coil of the electric motor 6 is energized, the motor shaft 7 starts to rotate. The rotational output of the electric motor 6 is transmitted from the worm gear 51 fixed to the motor shaft 7 to the helical gear 52, from the helical gear 52 to the output spur gear 53 via the shock absorbing member (elastic member 59 and the like), and further to the output spur gear. 53 to the input spur gear 61 in order. The rotational output of the electric motor 6 taken out from the input spur gear 61 to the outside of the motor actuator 5 is transmitted to the valve shaft 33 of the intake flow control valve 3. As a result, the intake flow control valve 3 rotates around the rotation center axis of the valve shaft 33 against the urging force of the coil spring 4, and the main port 32 is fully closed (closed).

  As a result, the intake air filtered by the air cleaner 21 flows into the intake port 17 of the engine 1 via the intake passage of the engine intake pipe 11. At this time, since the main port 32 is closed by the intake flow control valve 3, a one-sided ventilation state of only the swirl port 31 is formed. Thereby, a lateral vortex flow (swirl flow) is generated in the intake air in the cylinder 12 of the engine 1. Due to the generation of the intake vortex, the combustion speed in the cylinder 12 is accelerated, the combustion efficiency is improved, and the fuel efficiency and emission during idling are improved. Here, in this embodiment, the energization control of the armature coil of the electric motor 6 is performed at the time of engine start or idle operation, and the valve opening (valve position) of the intake flow control valve 3 is fully closed (fully closed position). It is trying to become. That is, the normally open intake flow control valve 3 is driven to close by the motor actuator 5. On the contrary, at the time of engine start or idle operation, the energization of the armature coil of the electric motor 6 is stopped and the valve opening (valve position) of the intake flow control valve 3 is fully adjusted by the urging force of the coil spring 4. You may make it be a closed state (fully closed position). In this case, a normally closed intake flow control valve is obtained.

[Effect of Example 1]
As described above, in the motor actuator 5 of the intake vortex generator for an internal combustion engine of this embodiment, the backlash in the thrust direction of the motor shaft 7 of the electric motor 6 and the worm gear 51 is prevented and the flapping of the intake flow control valve 3 is prevented. Coil spring for applying a pressure to overcome the reaction force caused by vehicle vibration or engine vibration to the worm gear 51 between the end frame 46 of the electric motor 6 and the bottom wall surface of the housing 9 for the purpose of suppressing 10, even if vehicle vibrations or engine vibrations are transmitted to the electric motor 6, the worm gear 51 is thrust in a gap (backlash) between the tooth surfaces of the worm gear 51 and the helical gear 52 that meshes with the worm gear 51. It ’s hard to get loose.

  As a result, the helical gear 52 installed on the valve side of the worm gear 51 fixed to the motor shaft 7 of the electric motor 6 corresponds to a predetermined amount of play around the axis of the shaft 54 press-fitted and fixed to the housing 9. Since it becomes difficult to swing by a predetermined rotation angle, fluttering of the intake flow control valve 3 due to vehicle vibration or engine vibration when the operation of the intake flow control valve 3 is stopped (for example, when the fully open position is fixed or when the fully closed position is fixed) is suppressed. It becomes possible to do. Thereby, since the self-locking effect of the intake flow control valve 3 and the helical gear 52 can be maintained, the tooth surface of the worm gear 51 and the tooth surface of the helical gear 52 collide or rub when the operation of the intake flow control valve 3 is stopped. Can be prevented.

  Thereby, abnormal wear of the tooth surface of the worm gear 51 and the tooth surface of the helical gear 52 can be prevented. As a result, even when the worm gear 51 is rotationally driven by the electric motor 6 when the intake flow control valve 3 is driven to close (or open), the worm gear 51 is not properly engaged with the helical gear 52 due to poor meshing between the worm gear 51 and the helical gear 52. Therefore, the problem that the worm gear 51 and the helical gear 52 are engaged with each other can be solved, so that the power transmission function of the gear transmission mechanism including the worm gear 51 and the helical gear 52 is not lost. Therefore, the performance as the motor actuator 5 is not impaired.

  Further, when the operation of the intake flow control valve 3 is stopped (for example, when the fully open position is fixed or when the fully closed position is fixed), the self that holds the intake flow control valve 3 at a predetermined operation stop position (for example, the fully closed position or the fully open position). Since the lock effect is lost and the intake flow control valve 3 can be prevented from flapping in the main port 32 of the housing 2, the opening area of the main port 32 of the housing 2 increases or decreases when the operation of the intake flow control valve 3 stops. The intake air amount sucked into the combustion chamber 14 of the engine 1 does not change. Therefore, fluctuations in the engine rotation speed can be prevented, and the drivability of a vehicle such as an automobile can be improved.

  Further, in the motor actuator 5 of the intake vortex generator for an internal combustion engine of the present embodiment, as described above, the motor shaft of the electric motor 6 is used for the purpose of suppressing the radial play of the motor shaft 7 of the electric motor 6. 7 and rubber elastic bodies 45 and 47 are interposed between the cylindrical bearing portion of the yoke housing 41 of the electric motor 6 and the cylindrical bearing portion of the end frame 46 of the electric motor 6. These rubber-based elastic bodies 45 and 47 are elastic members that can be elastically deformed in the radial direction (radial direction) of the motor shaft 7, and are vehicle vibrations and engine vibrations transmitted to the electric motor 6 via the housing 9. Is attenuated. The flapping suppression force is determined by adjusting the magnitude of the spring force (biasing force) of the coil spring 10 and the rubber hardness of the rubber-based elastic bodies 45 and 47. Further, instead of the rubber elastic bodies 45 and 47, a bearing member such as a ball bearing may be installed.

  4 and 5 show a second embodiment of the present invention. FIG. 4 shows the main structure of the motor actuator. FIGS. 5 (a) and 5 (b) show the electric motor and motor peripheral components. It is a figure.

  In this embodiment, as shown in FIGS. 4 and 5A, the thrust of the motor shaft 7 of the electric motor 6 and the worm gear 51 in the thrust direction is prevented, and the flapping of the intake flow control valve 3 is suppressed. Thus, with respect to the worm gear 51 between the front end surface (gear side end surface) of the yoke housing 41 of the electric motor 6 and the motor side end surface of the flange plate 71 formed integrally with the motor side end of the worm gear 51, A coil spring 10 for applying a pressure that overcomes a reaction force caused by vehicle vibration or engine vibration is disposed. The coil spring 10 is disposed on the outer periphery of the motor shaft 7 of the electric motor 6. Instead of the flange plate 71, an annular washer may be installed.

  Further, in this embodiment, as shown in FIG. 5A, the outer periphery of the motor shaft 7 of the electric motor 6 and the housing 9 are restricted for the purpose of suppressing the radial play of the motor shaft 7 of the electric motor 6. A rubber-based elastic body (elastic member, rubber member) 73 is interposed between the inner periphery of the through hole of the shaft bearing portion 72. The rubber-based elastic body 73 is an elastic member that can be elastically deformed in the radial direction of the motor shaft 7 of the electric motor 6, such as vehicle vibration transmitted to the electric motor 6 through the shaft bearing portion 72 of the housing 9. It is possible to damp engine vibrations. The flapping suppression force is determined by adjusting the magnitude of the spring force (biasing force) of the coil spring 10 and the rubber hardness of the rubber-based elastic body 73.

  Further, in the present embodiment, as shown in FIG. 5B, for the purpose of preventing the backlash in the thrust direction of the motor shaft 7 and the worm gear 51 of the electric motor 6 and suppressing the fluttering of the intake flow control valve 3. The motor is provided so as to protrude from the rear end surface of the end frame 46 of the electric motor 6 to the other side (right side in the figure) of the rotation axis direction (rotation center axis direction of the motor shaft 7: hereinafter referred to as the axial direction or thrust direction). Between the housing side end surface of the flange plate 74 integrally formed at the rear end portion of the shaft 7 and the bottom wall surface of the housing 9, the worm gear 51 is overcome with a reaction force caused by vehicle vibration or engine vibration. A coil spring 10 for applying a pressure is arranged. The coil spring 10 is disposed on the outer periphery of the motor shaft 7 of the electric motor 6. Instead of the flange plate 74, an annular washer may be installed.

  Further, in this embodiment, as shown in FIG. 5 (b), the outer periphery of the motor shaft 7 of the electric motor 6 and the housing 9 are restricted for the purpose of suppressing the radial play of the motor shaft 7 of the electric motor 6. A rubber-based elastic body (elastic member, rubber member) 76 is interposed between the inner periphery of the through hole of the shaft bearing portion 75. The rubber-based elastic body 76 is an elastic member that can be elastically deformed in the radial direction of the motor shaft 7 of the electric motor 6. The rubber-based elastic body 76 transmits vehicle vibration transmitted to the electric motor 6 via the shaft bearing portion 75 of the housing 9. It is possible to damp engine vibrations. Note that the flapping suppression force is determined by adjusting the magnitude of the spring force (biasing force) of the coil spring 10 and the rubber hardness of the rubber-based elastic body 76.

  6 and 7 show a third embodiment of the present invention. FIG. 6 shows a state in which a swirl flow is generated in the combustion chamber of the engine. FIG. 7 shows a tumble flow in the combustion chamber of the engine. It is the figure which showed the state made to raise.

  In the present embodiment, a spark plug (spark plug) 20 is installed on the cylinder head at the top of the combustion chamber 14 of the engine 1. Here, in FIGS. 6 and 7, a dual-type intake valve 16 and a double-type exhaust valve 18 are provided for the combustion chamber 14 of one cylinder, but one for the combustion chamber 14 of one cylinder. Only one or three or more intake valves 16 may be provided, or only one or three or more exhaust valves 18 may be provided. In the case of this embodiment, it is desirable to provide a fuel injection valve (injector) in the cylinder head so that fuel is injected toward the back wall surface (valve face) of the intake valve 16 of the engine 1.

  In this embodiment, as a moving body (for example, a rotary type valve), as shown in FIG. 6, the intake air (air mixture) flowing from the intake port of the engine 1 into the combustion chamber of the cylinder of the engine 1 is laterally transmitted. Although an intake flow control valve (swirl flow control valve) for generating a vortex flow (swirl flow) is employed, as a moving body (for example, a rotary valve), as shown in FIG. An intake flow control valve (tumble flow control valve) that causes a vertical vortex flow (tumble flow) in the intake air (air mixture) flowing into the combustion chamber of the cylinder of the engine 1 may be employed.

[Modification]
In this embodiment, the motor actuator of the present invention is applied to the motor actuator 5 that drives the intake flow control valve 3 to close (or opens), but the intake variable used in the variable intake device for the internal combustion engine is used. The present invention may be applied to a motor actuator that drives the valve 26 to open (or close). Note that the variable intake device for the internal combustion engine switches the intake passage by the intake variable valve 26 so that the passage length of the intake passage of the intake manifold 23 is extended, for example, when the engine rotational speed is in a low / medium speed rotation region, The engine output shaft torque (engine torque) is improved regardless of the engine rotation speed by switching the intake passage by the intake variable valve 26 so that the intake passage length of the intake manifold 23 is shortened when the speed is in the high speed rotation region. It is a system that can.

  In addition, the motor actuator of the present invention drives the electric motor in accordance with the amount of depression of the accelerator pedal of the driver, and controls the amount of intake air taken into the combustion chamber 14 of the engine 1. You may apply to the motor actuator which controls the throttle opening corresponding to the rotation angle of the throttle valve 25 used for a control apparatus. Note that the configuration of FIG. 2 may be applied to a throttle opening control device for an internal combustion engine as it is. In this case, the non-contact type valve opening degree detection device becomes a non-contact type throttle opening degree detection device.

  In addition, the moving body (valve such as a rotator) of the present invention is controlled by an intake control valve that controls the amount of intake air drawn into the combustion chamber of the engine, and an exhaust control that controls the amount of exhaust gas discharged from the combustion chamber of the engine. Valve, idle rotation speed control valve that controls the amount of intake air that bypasses the throttle valve, exhaust gas that controls the amount of exhaust gas recirculation that recirculates part of the exhaust gas discharged from the combustion chamber of the engine from the exhaust passage to the intake passage You may apply to a gas recirculation | reflux amount control valve (EGR control valve). In addition to the butterfly valve-type rotary valve as described above, the movable body of the present invention (valve such as a rotary body) can be a single-open rotary valve, a rotary valve, a poppet valve, or a shutter. The present invention may be applied to a valve of a type and a door type valve that is supported on only one side. The motor actuator of the present invention may be applied to a motor actuator that drives a moving body such as a passage switching door or an opening / closing door of a vehicle air conditioner. Further, the present invention may be applied to a motor actuator that drives a moving body such as a rotating body (rotor) of a fluid pumping machine (for example, a blower, a compressor, or a pump) that pressurizes and pumps a fluid such as gas or liquid.

  In this embodiment, when the operation of the intake flow control valve 3 is stopped, that is, when the intake flow control valve 3 is fixed at the fully open position, the supply of electric power to the armature coil of the electric motor 6 is stopped. The input spar gear 61 is moved by this and the input spar gear 61 comes into contact with the fully open stopper 66 so that the intake flow control valve 3 is fixed at the fully open position. When stopping, that is, when the intake flow control valve 3 is fixed at the fully open position, the intake flow control valve 3 may be fixed at the fully open position by a self-lock effect. Also, when the operation of the intake flow control valve 3 is stopped, that is, when the intake flow control valve 3 is fixed at the fully closed position, even if the supply of power to the armature coil of the electric motor 6 is stopped, the intake flow control valve is caused by the self-lock effect. You may comprise so that 3 may be fixed to a fully closed position.

1 is a schematic diagram showing a schematic configuration of an intake system for an internal combustion engine (Example 1). 1 is a schematic diagram showing a schematic configuration of an intake vortex generator for an internal combustion engine (Example 1). FIG. It is sectional drawing which showed the whole structure of the motor actuator (Example 1). (Example 2) which is the top view which showed the main structures of the motor actuator. (A), (b) is sectional drawing which showed the electric motor and motor peripheral components (Example 2). (Example 3) which showed the state which produced the swirl flow in the combustion chamber of the engine. (Example 3) which showed the state which produced the tumble flow in the combustion chamber of an engine. It is sectional drawing which showed the whole structure of the intake eddy current generator for internal combustion engines (prior art). It is the top view which showed the main structures of the valve drive device (prior art).

Explanation of symbols

1 engine (internal combustion engine)
2 Housing 3 Intake flow control valve (Intake flow control valve)
5 Motor actuator 6 Electric motor 7 Motor shaft (output shaft)
9 Housing 10 Coil spring (pressure applying means)
14 Combustion chamber 26 Intake variable valve (variable intake valve)
27 Intake passage 28 Intake passage 33 Valve shaft 42 Motor housing hole in housing 45 Rubber elastic body (elastic member)
47 Rubber elastic body (elastic member)
51 Worm gear (first gear)
52 Helical gear (second gear)
72 Housing shaft bearing 73 Rubber elastic body (elastic member)
75 Shaft bearing portion of housing 76 Rubber elastic body (elastic member)

Claims (7)

(A) a motor that generates a driving force for driving the moving body;
(B) a power transmission mechanism having a first gear driven by the motor and a second gear meshing with the first gear, and transmitting the driving force of the motor to the moving body;
(C) Applying a pressure that overcomes the reaction force caused by vibration in the direction in which the tooth surface of the first gear and the tooth surface of the second gear are pressed against the first gear or the second gear. And a pressure applying means. The motor actuator according to claim 1,
The motor has an output shaft extended in a thrust direction,
The first gear is a worm gear fixed to the output shaft of the motor,
The motor actuator characterized in that the second gear is a helical gear that meshes with the worm gear and rotates. The motor actuator according to claim 1,
The motor has an output shaft extended in a thrust direction,
The first gear is a helical gear fixed to the output shaft of the motor,
2. The motor actuator according to claim 1, wherein the second gear is a worm gear that meshes with the helical gear and rotates. The motor actuator according to claim 2 or 3,
A housing in which a motor housing hole for housing the motor is formed;
The motor actuator according to claim 1, wherein the housing includes a bearing portion that rotatably supports the output shaft via an elastic member that is elastically deformable in a radial direction of the output shaft. In the motor actuator according to any one of claims 1 to 4,
The motor actuator, wherein the moving body has a valve shaft that is drivingly connected to the power transmission mechanism, and is a valve that rotates integrally with the valve shaft. In the motor actuator according to any one of claims 1 to 5,
A housing that forms an intake passage communicating with the combustion chamber of the internal combustion engine;
The motor actuator, wherein the moving body is an intake air flow control valve that opens and closes a part of the intake air passage to generate a vortex in the air flowing from the intake air passage into the combustion chamber. In the motor actuator according to any one of claims 1 to 5,
A housing that forms an intake passage communicating with the combustion chamber of the internal combustion engine;
The motor actuator according to claim 1, wherein the moving body is a variable intake valve that changes a passage length or an opening area of the intake passage by opening and closing the intake passage.

Images