JP3751946B2 - Engine throttle device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to a throttle device that controls the opening of an engine throttle valve with an electric actuator. More specifically, the initial opening of the throttle valve when the engine key switch is turned off is determined from the fully closed position of the throttle valve. The present invention relates to a throttle device having a large setting mechanism.
[0002]
[Prior art]
  Conventionally, in the electronic throttle control system in which the engine throttle valve is driven and controlled by an electric actuator, the initial opening of the throttle valve at the time of engine key-off (in other words, when the motor for the throttle actuator is not energized) There has been proposed a technique for making the initial opening degree (sometimes referred to as initial opening degree) larger than the fully closed position (steady idle opening degree after warming up).
[0003]
  One reason for setting the initial opening is that it is necessary for combustion in the pre-warm-up operation (cold cold start) at the time of starting the engine without providing an auxiliary air passage (an air passage that bypasses the throttle valve). Ensuring air flow is an example. During idling, the throttle valve is controlled from the initial opening to the fully closed position (normal idle opening) as the engine is warmed up.
[0004]
  In addition to the initial opening, even if the throttle control system breaks down, ensuring self-running (limp home) or air flow to prevent engine stall, throttle valve is fixed to the inner wall of the throttle body with viscous material or ice etc. It responds to demands such as preventing it.
[0005]
  For example, in Japanese Patent Application Publication No. 2-500677, a return spring (first urging means) that urges the throttle valve in the closing direction and a counter spring that urges the throttle valve in the opening direction against the return spring. The force relation of the spring (second biasing means; initial opening spring) is set so that the force of the latter counterspring is larger than the return spring at the throttle initial opening position, and when the engine key switch is turned off, The throttle opening is set so that the free end is locked to the stopper at the initial opening position.
[0006]
  In Japanese Patent Laid-Open No. 3-271528, a sleeve (support member) that is a component of a relief lever is fitted in a free state in a rotational direction to a boss portion of a throttle body side wall that supports one end of a throttle shaft. The relief lever is urged in the closing direction of the throttle valve by the return spring (first urging means), while the throttle lever is fixed to the throttle shaft, and the relief lever is engaged with the throttle lever by the spring force of the return spring. When the motor is not energized, the throttle valve is stopped by a stopper at a predetermined position (a position where the opening is larger than the fully closed position of the throttle valve) by the engagement of the levers and the force of the return spring. Using the urging means 2 to urge the throttle lever in the opening direction of the throttle valve Holding the initial opening.
[0007]
  In Japanese Patent Laid-Open No. 4-203219, a lever is fixed to one end of a throttle shaft so as to cross the shaft, and a throttle valve is urged in the closing direction by a return spring (first urging means) at one end of the lever. A force is applied to the other end of the lever so as to urge the throttle valve in the opening direction in the vicinity of the throttle fully closed by the second urging means. When the force of the second urging means is equal to or less than the predetermined opening (throttle initial opening or less), the throttle initial opening is maintained by making it larger than the force of the first urging means.
[0008]
  In these conventional examples, when the throttle valve opening degree control is performed, the motor driving control is performed based on the control signal sent from the control system, and the throttle opening degree is to be made smaller than the throttle initial opening degree. Is performed by the driving torque of the motor acting in the closing direction of the throttle valve against the second urging means.
[0009]
[Problems to be solved by the invention]
  This type of initial opening setting mechanism is, for example, as disclosed in Japanese Patent Laid-Open No. 3-271528, a relief lever around one end of the throttle shaft, a throttle lever that engages with this, If the biasing means, stopper, etc. are arranged, the parts can be consolidated. However, in the conventional method, the sleeve (support member) that is the element of the relief lever is fitted to the boss portion of the throttle body side wall. When the sleeve moves following the rotation of the throttle shaft during throttle opening control, the sleeve slides on the outer periphery of the boss portion, so that friction is generated between the sleeve and the boss portion. Friction is a burden for the return spring and the motor drive, so it is desirable to reduce it as much as possible.
[0010]
  The first urging means (return spring) for urging the throttle valve in the closing direction and the second urging means (initial opening spring) for urging the throttle valve in the opening direction include a throttle initial opening degree. In order to have a surplus force at the position, the axial torque T1, T2 of any throttle shaft (T1 is the axial torque in the throttle valve closing direction at the initial opening position given by the first urging means, and T2 is the second additional torque. Both the axial torque in the throttle valve opening direction at the initial opening position given by the biasing means)
[0011]
[Equation 1]
    T1> Mf × Ge + Vf, T2> Mf × Ge + Vf
  It was a general idea to satisfy the relationship (where Mf: motor static friction torque, Ge: reduction ratio, Vf: required torque on the throttle shaft for opening the throttle valve) (note that In Japanese Patent Application Laid-Open Nos. 2-500677 and 4-203219, T1 <T2 is established below a predetermined opening degree near the throttle fully closed, whereas in Japanese Patent Application Laid-Open No. 3-271528, an initial opening stopper is used. In order to receive the force of 1 biasing means (return spring), at the throttle initial opening position, the force of T2 can be set without being constrained by T1, so that T1 ≧ T2 can be established. In any case, these are established on the premise of the above formula 1).
[0012]
  By the way, T1 is the axial torque in the direction of closing the throttle valve, and T2 is the axial torque in the direction of opening the throttle valve (here, T1 is a positive direction and T2 is a negative direction). The throttle shaft torque generated by the second urging means has a shaft torque step T1-(-T2) that changes suddenly at the throttle initial opening position. The greater the shaft torque step, the more difficult it is to control the throttle opening, so it is preferable to make the shaft torque step as small as possible in order to increase the throttle control accuracy.
[0013]
  The present invention has been made in view of the various points as described above, and its purpose is basically an initial opening degree setting device for a throttle valve.BuildingIncreasing the rationality of publicationIn the machineBy reducing the structural friction and improving the characteristics of the urging means (for example, improving the spring characteristics of the return spring, etc.), the burden of driving the throttle actuator is reduced and the throttle control operation is stabilized.
[0014]
[Means for Solving the Problems]
  The present invention
  Throttle body,
  A throttle shaft rotatably attached to the throttle body;
  A throttle valve provided on the throttle shaft;
  A motor housed in the throttle body;
  A fully closed position setting mechanism for setting a fully closed position of the throttle valve;
  An initial opening setting mechanism for setting an initial opening position of the throttle valve when the motor is not energized to be larger than the fully closed position;
  A reduction gear that decelerates and transmits the output of the motor to the throttle shaft;
An engine throttle device equipped with
  The initial opening setting mechanism is:
  A fitting member rotatably fitted to the throttle shaft;
  First biasing means for biasing the fitting member in a closing direction of the throttle valve;
  A stopper provided in the throttle body so as to prevent the fitting member from rotating in the closing direction from the initial opening position of the throttle valve;
  A member fixed to the throttle shaft;
  A second urging means that urges the fitting member and the member fixed to the throttle shaft to engage with each other;
  The throttle shaft to which the motor output is transmitted from the motor via the reduction gear is attached in the closing direction by the first urging means when the throttle valve is located on the opening side from the initial opening position. When the force acts, and when the throttle valve is positioned closer to the closing position than the initial opening position, the biasing force in the opening direction by the second biasing means acts,
Thus, when the throttle shaft rotates across the initial opening position, it acts on the throttle shaft by the first and second urging means acting on the throttle shaft at the initial opening position. By switching the direction of the urging force, the urging force acting on the throttle shaft is configured to generate a torque step,
  When the opening of the throttle valve is operated by the motor on the opening side from the initial opening position, the torque transmitted from the motor to the throttle shaft via the reduction gear and the first urging means The motor is controlled such that the opening of the throttle valve is controlled by balancing the torque acting on the throttle shaft,
  When the throttle valve is operated by the motor closer to the closing position than the initial opening position, the motor is controlled to resist the urging force of the second urging means,
  When the throttle valve opens and closes on the opening side from the initial opening position, a member fixed to the throttle shaft engages with the fitting member, so that the fitting member rotates integrally with the throttle shaft. ConfiguredIt is characterized by that.
[0015]
  According to such a configuration, when the engine key switch is off (when the motor is not energized), the force of the first urging means (valve closing force) passes through the engagement member and the engagement member fixed to the throttle shaft. The engagement member is locked to the stopper at the throttle initial opening position, and the force of the second urging means (valve opening force) acts on the throttle shaft. Is held at an initial opening position that is larger than the fully closed position.
[0016]
  In addition, when the throttle valve opening is controlled by a motor in the region above the throttle initial opening, the slot shaft and the shaft are usually operated integrally with the throttle shaft while the fitting member is on the throttle shaft. There is almost no friction between the fitting members. Therefore, by reducing the force (spring load) of the first urging means and thus reducing the required throttle shaft torque T1, the burden of driving the motor is reduced. Furthermore, the shaft step torque T1-(-T2) generated from the throttle initial opening position of the throttle shaft torque is also reduced, thereby improving the stability of the throttle drive control.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
  Embodiments of the present invention will be described with reference to the drawings.
[0018]
  FIG. 1 is a longitudinal sectional view showing a throttle device according to the first embodiment, FIG. 2 is a view taken in the direction of arrow A, FIG. 3 is an exploded perspective view, and FIG.
[0019]
  In these drawings, the throttle body 15 is made of, for example, aluminum die casting, and an intake passage (bore) 30 is formed therein. A throttle shaft 18 passes through the throttle body 15 at right angles to the intake passage 30 and is rotatably supported via bearings 28 and 29. A throttle valve 24 that controls the intake air amount in the intake passage 30 is controlled by the throttle shaft 18. Is fixed. A pipe 26 passes engine coolant through the throttle body 1 and manages the throttle body 26 at the engine coolant temperature.
[0020]
  The left and right side wall surfaces orthogonal to the throttle shaft 18 among the side walls of the throttle body 15 are provided with a bearing housing portion 15C for housing the bearing 29 and the seal 32 on one surface, and a gear group for driving the electronic throttle control system. A housing portion 15A for housing is formed integrally with the body 15, and a bearing housing portion 15D for housing the bearing 28 and the seal 31 on the opposite surface, and a limp home mechanism and an initial opening setting mechanism for the throttle valve are housed. A case portion 15B is provided.
[0021]
  The limp home mechanism is for enabling emergency self-running with a mechanical accelerator mechanism when an electronic throttle (actuator or its control system) fails. The initial opening setting mechanism is for setting the initial opening of the throttle valve 24 when the engine key is turned off (when the motor is not energized). The initial opening of the throttle valve is set to, for example, 5 ° (± 0.2 °), and the opening of the throttle valve in the fully closed position (the throttle valve fully closed position is an opening at which an idle air flow rate can be secured). (Corresponding) is set larger. The configurations of the limp home mechanism and the initial opening setting mechanism will be described later. The reason for setting the initial opening has already been described and will not be described.
[0022]
  The gear group housing case portion 15A is covered with a cover 21 that can be removed by screwing, and houses the gears 11, 9A, 9B, 10 and the like of the throttle drive system in the inside 20. On the other hand, the case portion 15B is covered with a cover 22 that can be attached and detached by screwing provided with the accelerator levers 1, 1 ', the accelerator shaft 34, the accelerator position sensor 13, and the like.
[0023]
  The accelerator cover 22 has a boss 90 that supports the accelerator shaft 34 penetrating the cover 22 via bearings 93 and 94, and the first accelerator lever 1 with the accelerator wire coupling portion 33 is provided at one end of the accelerator shaft 34. Fixed placement.
[0024]
  A spring support member 91 is fitted on the outer periphery of the boss 90. The other end of the accelerator shaft 34 is introduced into the cover 22, and a second accelerator lever (cam lever) 1 ′ is fixedly disposed on the other end of the shaft 34. These levers 1 and 1 ′ are fixedly arranged by using clamping between the tightening nuts 35 and 92 disposed at both ends of the accelerator shaft 34 and the stepped portion of the shaft 34.
[0025]
  On the outer periphery of the spring support member 91, an accelerator return spring 8 constituted by a coiled twisted spring is mounted. The return spring 8 has one end connected to the first accelerator lever 1 side and the other end connected to the cover 22 side, and urges the accelerator shaft 34 and the accelerator levers 1, 1 ′ in the closing direction. The accelerator levers 1, 1 ′ rotate in the opening direction against the force of the return spring 8 through the wire 44 by depressing the accelerator pedal.
[0026]
  However, when the throttle shaft 18 is electrically rotated by the motor 12, the cam-type accelerator lever 1 ′ does not transmit power to the throttle shaft 18. Reference numeral 95 denotes a seal member.
[0027]
  A motor case portion 15E is provided in a part of the side wall of the throttle body 15 (lower portion in FIG. 1) in parallel with the throttle shaft 18, and the motor 12 serving as an actuator for electronic throttle is accommodated in the motor case portion 15E. The As the motor 12, a DC motor, a stepping motor, or the like is used.
[0028]
  The inner periphery of the motor case portion 15E has a tapered shape to facilitate the insertion of the motor 12, the elastic member 27 is interposed at the back end of the case portion 15E, the motor stopper plate 96 is disposed at the case opening, and the screw 97 With the tightening, the elastic member 27 and the stop plate 96 hold the motor 12.
[0029]
  A motor gear (pinion gear) 11 provided on the shaft 12A of the motor 12 meshes with the intermediate gear 9A. The intermediate gear 9A has a larger gear ratio than the motor gear 11 and functions to reduce and increase torque. This increased rotational torque is further transmitted to the throttle shaft 18 via the intermediate gear 9 and the throttle gear 10.
[0030]
  The intermediate gears 9 </ b> A and 9 </ b> B are integrated, and are rotatably fitted to a gear support shaft 25 arranged in parallel with the throttle shaft 18. One end of the gear support shaft 25 is supported by press-fitting into the hole 98 on the side wall of the slot body 15 and is pressed by the cover 21 via the nylon washer 100 so that the intermediate gear 9 does not come off the shaft 25.
[0031]
  The throttle gear 10 is fixed to one end of the throttle shaft 18 by tightening a nut 23. As an example, the throttle gear 10 uses a fan-shaped gear as shown in FIG. 3. When the throttle gear 10 is rotated in the closing direction of the throttle valve, a throttle fully closed position provided on one side of the throttle body 15 is finally provided. By contacting the adjusting screw (idle opening adjusting screw; first stopper) 7, further rotation of the throttle shaft 18 in the closing direction is restricted, and the fully closed position of the throttle valve 24 is determined. . The throttle valve fully closed position is set to the minimum opening that can secure the idle air flow after warm-up.
[0032]
  Since the throttle device according to the present embodiment employs an electronic throttle system, as long as the drive motor 12 of the throttle control system is operating normally, the torque of the motor 12 is applied to the throttle shaft 18 via the gear mechanism. Is given.
[0033]
  A drive current is supplied to the motor 12 from a throttle control module (TCM) (not shown). The TCM creates the drive current command value as follows. That is, an accelerator position signal and a throttle position sensor (hereinafter referred to as a throttle sensor) 13 from an accelerator position sensor (which detects the amount of depression of the accelerator pedal 53 shown in FIG. 5 and may also be referred to as an accelerator sensor hereinafter) 13. The throttle opening signal, the engine speed, the slip signal, etc. are input, and the normal engine operation control and traction control according to the operation mode are created.
[0034]
  As long as the throttle control system is operating normally, the throttle shaft 18 and the accelerator shaft 34 are separately provided as an offset so that the mechanical power from the accelerator pedal 53 is not transmitted to the throttle shaft 18. There is an accelerator lever 1 ′ and a lever 2 which are elements of a limp home mechanism between the throttle shaft 18 and the accelerator shaft 34.
[0035]
  Here, the limp home mechanism and the initial opening setting mechanism will be described. In this example, these mechanisms are arranged on the side opposite to the side where the throttle body 15 is provided with the throttle body 15 interposed therebetween.
[0036]
  The initial opening setting mechanism is a lever 2 that is rotatably fitted to one end of the throttle shaft 18 (corresponding to the lever A or the return lever described in the claims, hereinafter the lever (A) 2) and a return spring (first biasing means) 4 for biasing the sleeve 42 with the lever (A) 2 in the closing direction of the throttle valve 24, and a return fixed to one end of the throttle shaft 18. A lever 3 that can be engaged with the lever (A) 2 by the spring force of the spring 4 (corresponding to the lever B or throttle lever described in the claims, hereinafter referred to as lever (B) 3); Initial opening adjustment that prevents rotation in the closing direction of the sleeve 42 with the lever (A) 2 at the initial opening position when the power is off (when the engine key switch is off). Composed of the (second stopper) 6, and the initial opening spring (second biasing means) 5 for imparting valve opening force to keep the initial opening degree to the throttle shaft 18.
[0037]
  A specific mounting structure of these elements will be described with reference to FIGS.
[0038]
  As shown in FIG. 3, the throttle shaft 18 has a flat shape having at least two parallel surfaces at one end, and a spacer 50 is inserted into one end of the shaft 18 so as to be applied to the shaft step portion 18 ′. After the washer 51 is inserted, the tip 38 with the initial opening spring 5 is inserted in an engaged state, and then the sleeve 42 with the lever (A) 2 is loosely fitted through the sleeve 45 after the nylon washer 43. The lever (B) 3 is inserted into the throttle shaft 18 in an engaged state, and finally a nut 47 is tightened via a washer 46.
[0039]
  As shown in FIG. 4A, the sleeve (first sleeve) 45 has one end abutting against the tip 38 and the other end abutting against the lever (B) 3 by tightening the nut 47, so that the throttle shaft 18. Fixed to the outer periphery. The tightening force of the nut 47 is applied to the lever (B) 3, the sleeve 45, and the tip 38, and the tightening force is applied to the sleeve (second sleeve) 42 with the lever (A) 2 fitted to the outer periphery of the sleeve 45. In this way, the sleeve 42 can be rotated relative to the throttle shaft 18 and the sleeve 45.
[0040]
  As shown in FIG. 4, a solid lubricating member (dry bearing) 52 such as a fluorine resin coating is applied to the inner surface of the sleeve.
[0041]
  As shown in FIG. 3, the lever (A) 2 has arms 2 </ b> A to 2 </ b> D, and a central mounting hole 2 </ b> E is inserted into the outer periphery of the sleeve (fitting member) 42 and is integrated with the metal sleeve 42 by caulking. It has become.
[0042]
  The arm portion 2A of the lever (A) 2 can be engaged with the lever (B) 3, and the projection (roll pin) 2B ′ that is a part of the arm portion 2B can be engaged with the accelerator lever (cam lever) 1 ′. One end 5A of the initial opening spring 5 is locked (connected) to the protrusion 2C ′ which is a part of the portion 2C, and the arm opening 2D is provided with an initial opening adjusting screw (stopper) 6 provided on the side wall of the throttle body 18. The engagement is set. The other end 5B of the initial opening spring 5 is connected to the tip 38.
[0043]
  In this example, both the return spring 4 and the initial opening spring 5 are spiral springs.
[0044]
  The return spring 4 is engaged with a sleeve 42 at one end 4B and a pin 37 provided at the other end 4A on the side wall of the throttle body 15, and receives the spring force of the return spring 4 to receive the arm portion 2A of the lever (A) 2. Engages with the lever (B) 3. By this engagement, the return spring 4 urges the throttle shaft 18 and thus the throttle valve 24 in the closing direction.
[0045]
  Here, an operation example of the present embodiment will be described with reference to the principle diagram of FIG. 5 and FIGS.
[0046]
  Due to the force in the closing direction of the return spring 4, the lever (A) 2 urges the throttle shaft 18 in the closing direction via the lever (B) 3 when the engine is keyed off (when the motor is not energized). The valve 24 is returned to a position corresponding to the initial opening. At the initial opening position, the lever (A) 2 has its arm portion 2D in contact with the stopper 6 and is prevented from further rotation in the closing direction.
[0047]
  Due to the presence of the stopper 6, the spring force of the return spring 4 is not applied from the initial opening θ2 of the throttle valve to the fully closed position, and in the vicinity of this fully closed position (between the fully closed position and the initial opening θ2), as described above. The initial opening degree of the throttle valve 24 is maintained by applying the initial opening degree spring 5 (applying a valve opening force to the throttle shaft 18).
[0048]
  The urging force P1 in the closing direction of the return spring 4 and the urging force P2 in the opening direction of the initial opening spring 5 at the initial opening position are P1 ≧ P2, in other words, the opening direction by the shaft torques T1 and P2 in the closing direction by P1. The shaft torque T2 is established so that T1 ≧ T2.
[0049]
  By maintaining this initial opening, it is possible to secure an air flow rate necessary for starting the engine even if the throttle valve is iced even in a pre-warm-up operation during cold weather.
[0050]
  When the throttle valve 24 is controlled to the fully closed position (when idle operation after warming-up is performed), the throttle shaft 18 is made the spring force of the initial opening spring 5 by the power of the motor 12 based on the idle control command value. Rotate in the closing direction.
At this time, in the range from the initial opening to the fully closed position, the lever (B) 3 disengages from the lever (A) 2 as shown by a broken line 3 'in FIG. Close operation.
[0051]
  When the throttle valve 24 is controlled to open (open / close) within the range of the initial opening θ2 or more, the power of the motor 12 is transmitted to the throttle shaft 18 via the gear mechanisms 9 to 11 in a normal operation state. It is controlled by the balance between the force and the spring force of the return spring 4. At this time, the lever (A) 2 and the lever (B) 3 are engaged, and the sleeve 42 with the lever (A) 2 rotates integrally with the shaft 18 while riding on the throttle shaft 18 via the sleeve 45. To do.
[0052]
  In the traction control state, for example, a slip occurs and the driver fully depresses the accelerator pedal 53, and the rotational displacement of the accelerator lever 1 'is large. When 12 controls the throttle valve 24 in the closing direction, the lever (A) 2 is locked to the accelerator lever 1 'in the returning process and is prevented from further rotation in the closing direction. Even if such a state occurs, the lever (B) 3 is detached from the lever (A) 2 and rotates together with the throttle shaft 18 in the closing direction against the force of the spring 5 for the initial opening, so that the throttle The closing direction control (traction control) of the valve 24 is performed without any trouble.
[0053]
  When the traction control is performed, when the lever (A) 2 is locked with the accelerator lever 1 ′ as described above, the spring force of the return spring 4 impacts the accelerator lever 1 ′ through the lever (A) 2. This causes a phenomenon (kickback phenomenon) to be added.
[0054]
  In this kickback, the accelerator pedal 53 is depressed and the accelerator shaft 34 is at least θ1 as shown in FIG. 6A. [Θ1 is the accelerator shaft 34 is rotated by depression of the accelerator pedal and the accelerator lever 1 'is limp home. The angle is such that the lever can be engaged with the lever (A) 2 on the throttle shaft 18 side], but the cam has the throttle opening on the vertical axis and the accelerator opening (rotation angle of the accelerator shaft) on the horizontal axis. The smaller the characteristic gradient, the smaller the kickback can be achieved because the accelerator lever 1 'receives the spring force at a position where the spring load of the return spring is small in the case of traction control (particularly in the situation where kickback occurs).
[0055]
  However, since it is necessary to secure the accelerator opening θ3 necessary for self-running at the time of limp home, the cam shape of the accelerator lever 1 ′ is used as shown by the broken line in FIG. Only the middle of the characteristic (throttle opening-accelerator opening characteristic) is made a non-linear characteristic that becomes smaller than the linear gradient.
[0056]
  In this example, as shown in FIG. 6B, θ1 = 30 °, θ2 (initial opening) = 5 °, throttle opening required for limp home θ3 (throttle opening required for limp home) = 7 ° Set to.
[0057]
  The sleeve 42 relatively rotates on the sleeve 45 from the initial opening θ2 to the fully closed position of the throttle valve 24, and may also relatively rotate on the sleeve 45 in the case of traction control as described above. . The friction caused by the sliding is reduced by the solid lubricating member 52.
[0058]
  The limp home mechanism operates as follows.
[0059]
  When the throttle control system or the motor 12 fails, the throttle valve 24 is returned to the initial opening position by the spring force of the return spring 4. In this state, when the accelerator pedal 53 is depressed more than θ1, the cam loop 1′A of the accelerator lever 1 is engaged with the lever (A) 2 by the relative rotation of the accelerator shaft 34 with respect to the throttle shaft 18, and the lever (A) 2 is shown in FIG. 5, the throttle valve is rotated in the opening direction. The throttle shaft 18 and the lever (B) 3 follow the rotation of the lever (A) 2 in the opening direction by the force of the initial opening spring 5, the throttle valve 24 is opened, and the accelerator pedal runs on its own (Limp home). Is possible.
[0060]
  In this case, in order to guarantee the operation of the limp home, the shaft torque T1 due to the urging force P1 of the return spring 4 must satisfy the following condition at least at the initial opening θ2 to the throttle fully open position, Regarding the shaft torque T2 due to the urging force P2 of the spring 5, it is necessary to satisfy the following conditions at least from the throttle fully closed position to the return home travel region.
[0061]
[Equation 2]
                  T1> Mf × Ge + Vf
                  T2> Mf × Ge + Vf
It is necessary to satisfy the following conditions.
[0062]
  The effect of this embodiment is as follows.
[0063]
  a. The sleeve 42 with the lever (A) 2 used for driving the throttle shaft is exceptional in most of the opening range from the initial opening to the throttle fully opened position (the throttle is depressed with the accelerator pedal fully depressed in the traction control). Except when the valve is squeezed by a motor), the friction between the sleeve 42 and the sleeve 45 can be almost eliminated since the sleeve 45 rotates integrally with the throttle shaft 18.
[0064]
  Therefore, the force P1 of the return spring is reduced, and hence the required shaft torque T1 of the throttle shaft 18 is reduced, and the burden of driving the motor is reduced. Furthermore, the shaft step torque T1-(-T2) generated from the throttle initial opening position of the throttle shaft torque is also reduced, thereby improving the stability of the throttle drive control.
[0065]
  b. Components that are components of the initial opening setting mechanism [spacer 50, washer 51, tip 38 with spring 5 for initial opening, sleeve 45, return spring 4, sleeve 42 with lever (A) 2, lever (B) 3, etc. ] Can be sequentially inserted into the throttle shaft 18 and assembled only by tightening the nuts, so that the mounting operation can be rationalized.
[0066]
  c. The initial opening degree setting mechanism, limp home mechanism, throttle sensor 13, accelerator sensor 14, cover 22 of the case portion 15B, etc. are arranged in a centralized manner, and part of the mechanical parts are made common so that the number of parts can be increased. In addition, the structure can be rationalized and the apparatus can be miniaturized. In addition, since a spiral spring is used for the return spring 4 and the initial opening spring 5, the apparatus can be made more compact.
[0067]
  In addition, when a spiral spring is used, it is easy to design a spring having a small spring constant, which helps to reduce the load on the motor 12.
[0068]
  d. The stopper (idle opening adjusting screw) 7 of the fully closed position setting mechanism and the stopper (initial opening adjusting screw) 6 of the initial opening setting mechanism can both set the opening freely, and both stoppers Are provided on opposite surfaces of the throttle body side wall, so that both stoppers can be easily identified from the direction of the side wall and the presence of the gear mechanism and the initial opening mechanism without any hesitation. This eliminates misunderstandings and prevents adjustment errors.
[0069]
  In addition, by making the stopper (idle opening adjusting screw) 7 of the fully closed position setting mechanism abut on one side of the sector gear 10 of the reduction gear mechanism, a part of the gear can be used as a stopper locking member on the throttle shaft side. Can also be used.
[0070]
  e. Even when the limp home mechanism and the initial opening mechanism are mixed, the operation of the throttle shaft can be smoothly performed by the limp home mechanism during the traction control.
[0071]
  Further, by setting the characteristics of the accelerator lever 1 'of the limp home mechanism to a non-linear characteristic as shown by the broken line in FIG. 6A, the occurrence of kickback at the time of traction control can be suppressed.
[0072]
  Next, a second embodiment will be described with reference to FIGS. FIG. 8 is a longitudinal sectional view of the second embodiment, FIG. 9 is an exploded perspective view of an essential part thereof, and FIG. 10 is a sectional view of an essential part thereof.
[0073]
  The principle configuration of the present embodiment is the same as that of the first embodiment, and the difference is that some of the parts used are changed. Here, only this difference will be described. In the figure, the same reference numerals as those in FIG. 1 denote the same elements (the same applies to the following drawings).
[0074]
  In this example, for the return spring and the initial opening spring, the former uses a coiled torsion spring 63 and the latter uses a coiled torsion spring 64.
[0075]
  At one end of the throttle shaft 18, in addition to the lever (B) 3, another lever B ′ indicated by reference numeral 3 ′ (hereinafter referred to as lever (B ′) 3 ′) is fixedly disposed. , 3 ′, a sleeve 45 fixed to the shaft 18 by tightening a nut 47 is disposed, and a sleeve 42 with a lever (A) 2 is rotatably fitted to the sleeve 45 on the outer periphery of the sleeve 45.
[0076]
  On the outer periphery of the sleeve 42 on the throttle shaft 18, spring holders 61 and 62 with flanges divided into two in the axial direction are arranged in a free state in the rotational direction.
[0077]
  As shown in FIG. 10, the spring holders 61 and 62 have inner cylindrical portions 61A and 62A that fit around the outer periphery of the sleeve 42, and outer cylindrical portions 61B and 62B that divide the spring set space into two inside and outside. In the embodiment, the return spring 63 is disposed in the inner set space, and the initial opening spring 64 is disposed in the outer set space.
[0078]
  Further, as shown in FIG. 9, the spring holders 61 and 62 are formed with notches (spring end lead-out portions) 67 and 68 for pulling out the end portions 63A and 63B of the return spring 63 disposed inside. . Among these, one end 63A of the return spring 63 is locked to the pin 37 provided on the side wall of the throttle body 15 through the notch 68, and the other end 63B is locked to the arm portion 2D of the lever (A) 2 through the notch 67.
[0079]
  One end 64A of the spring 64 for initial opening disposed outside is locked to the lever (B ′) 3 ′ fixed to the throttle shaft 18, and the other end 64B is locked to the arm portion 2D of the lever (A) 2.
[0080]
  In this embodiment, the arm 2A of the lever (A) 2 is engaged with the lever (B) 3 fixed to the throttle shaft 18 by the return spring 63, and the throttle shaft 18 is biased in the closing direction of the throttle valve 24. Is done. The lever (A) 2 is in contact with the initial opening adjustment screw 6 and is prevented from further rotation in the closing direction, as in the first embodiment.
[0081]
  The initial opening spring 64 biases the throttle shaft 18 via the lever (B ′) 3 ′ in the valve opening direction so that the initial opening can be maintained near the fully closed position.
[0082]
  The divided spring holders 61 and 62 are pressed against the levers 3 and 3 'by receiving the force of the springs 63 and 64 in the axial direction.
[0083]
  According to this example, in addition to the same effects as those of the first embodiment, the following effects can be obtained.
[0084]
  f. The spring holders 61 and 62 are divided into two in the axial direction, and the holders 61 and 62 have partition walls (outer cylinder portions) 62A and 62B, so that the return spring 63 and the initial opening spring 64 interfere with each other. The inner and outer double arrangement structure can be easily mounted on the spring holder while consolidating parts.
[0085]
  g. In addition, the return spring 63 on the inner side and the initial opening spring 64 on the outer side allow the return spring 63 arranged on the inner side to have a smaller coil diameter and a smaller spring constant. The load-the horizontal axis is the opening of the throttle valve) can be made as flat as possible, and as a result, the burden on the throttle drive actuator can be reduced.
[0086]
  The return spring 63 may be disposed on the outside and the initial opening spring 64 may be disposed on the inside.
[0087]
  Next, a third embodiment will be described with reference to FIGS.
[0088]
  FIG. 11 is a sectional view of an essential part of the third embodiment, and FIG. 12 is an exploded perspective view thereof. Although not shown in FIGS. 11 and 12, the throttle body intake passage 30 and the throttle valve 24 mounting structure used in the first and second embodiments, the gear mechanisms 9A, 9B, 10, 11 and The mounting structure of the accelerator shaft 34 and the levers 1 and 1 'of the accelerator cover 22 are the same as in the previous embodiment.
[0089]
  In the present embodiment, one of the return spring and the initial opening spring is twisted in a coil shape, and the other is a spiral spring. Here, a return spring 63 by a coiled twist and an initial opening spring 5 by a spiral spring are used.
[0090]
  Further, a sleeve 70 is used in place of the sleeve 42 with the lever (A) 2 instead of the conventional sleeve 42.
[0091]
  In addition to the lever (A) 2, the sleeve 70 includes an inner cylinder portion 70 </ b> A that is rotatably fitted to the sleeve 45 and an outer cylinder that is disposed outside the sleeve 45, as shown in FIGS. Part 70B.
[0092]
  The inner cylinder portion 70A is made shorter than the outer cylinder portion 70B, and the initial opening spring 5 is placed on the throttle shaft 18 via the tip 38 using the inner space of the sleeve 70 corresponding to the shortened cylinder length. The one end 5A is locked to a notch 70C provided in the holder 70 as shown in FIG. 12 (the other end 5B is locked to the chip 38).
[0093]
  Spring holders 71 and 72 that are divided into two in the axial direction are fitted into the outer cylindrical portion 70 </ b> B of the sleeve 70.
[0094]
  The return spring 63 is supported by spring holders 71 and 72, and one end 63A of the return spring 63 is engaged with the pin 37 of the throttle body 15 through a notch 72A provided in the holder 72, and the other end 63B is an arm of the lever (A) 2. Lock to the part 2D.
[0095]
  This embodiment also has the same effects as those of the first embodiment, and further has the following effects.
[0096]
h. Even if different types of springs, such as coil springs and spiral springs, are used for the return spring and the initial opening spring, these springs can be centrally arranged in one sleeve, making the device compact. .
[0097]
  FIG. 13 is an exploded perspective view of the fourth embodiment, and FIG. 14 is a sectional view of an essential part thereof.
[0098]
  This embodiment is a type in which one of the return spring and the initial opening spring is a spiral spring and the other is a tension spring, and the initial opening setting mechanism is a throttle driven in this embodiment in order to make the body compact. It is arranged on the gear mechanism side of the system. As for the gear mechanism, only the throttle gear 10 is illustrated, and the gears 9A, 9B, and 11 are not illustrated.
[0099]
  In this example, as shown in FIG. 13, the lever (B) 3 is fixedly arranged next to the throttle gear 10 at one end of the throttle shaft 18 on the gear mechanism side, and then the washer 51, the return spring 4 and the lever (A) 2 are attached. The sleeve 42, washer 51 ′, and sleeve 45 are inserted and tightened with the nut 23. The return spring 4 uses a spiral spring. As the initial opening spring, a tension spring is used as will be described later.
[0100]
  As in the above-described embodiments, the sleeve 45 is fixed on the throttle shaft 18 by the tightening of the nut 23 and the interaction with the throttle shaft step 18 ′, and the sleeve 42 is disposed on the outer periphery of the sleeve 45. Is fitted to be rotatable.
[0101]
  As shown in FIG. 14A, the return spring 4 has one end 4A engaged with a pin 37 fixedly disposed on the throttle body 15, and the other end engaged with a sleeve 42, and the sleeve 42 and the lever (A) 2 are engaged. Energized in the closing direction of the throttle valve.
[0102]
  On the other hand, the lever (B) 3 has its arm portion 3A engageable with the arm portion 2A of the lever (A) 2, and one end 85B of the initial opening spring 85 is locked to the arm portion 3B. One end of the initial opening spring 85 is locked to the arm portion 2C of the lever (A) 2 and the other end is locked to the arm portion 3B of the lever (B) 3.
[0103]
  Also in the present embodiment, the initial opening setting operation is the same as in the above-described embodiment, and the spring force of the return spring 4 is engaged through the engagement of the lever (A) 2 and the lever (B) 3 when the engine key is off. The arm 2D of the lever (A) 2 is brought into contact with the adjusting screw 6 at the initial opening position, and the initial opening of the throttle valve is maintained by the force of the initial opening spring 85 at this time. The
[0104]
  If the motor (throttle actuator) is driven from this position in the closing direction against the pulling force of the initial opening spring 85, the throttle valve is fully closed at the position of the adjusting screw 7.
[0105]
  The throttle sensor 14 is also disposed on the side wall surface of the throttle body on the gear mechanism side.
[0106]
  In the present embodiment, the same effects as those of the above-described embodiments can be basically obtained, but the following effects are further achieved.
[0107]
  i. The gear mechanism of the throttle drive system and the initial opening mechanism can be centrally arranged. Since the gear mechanism, the return spring, and the initial opening spring are arranged close to the shaft 18, it is possible to reduce the torque in the opposite directions that interact with each other.
[0108]
  FIG. 15 is a sectional view showing a fifth embodiment of the present invention. In this embodiment, a limp home mechanism is not installed (so-called full electric control type), and the accelerator shaft, the accelerator lever, and the accelerator sensor are separately installed outside the throttle body (the accelerator mechanism relates to the accelerator position). It is used to generate a signal and is not directly involved in opening and closing the throttle valve, so it can be set separately.)
[0109]
  Also in this example, an initial opening mechanism is disposed on the gear mechanism side of the throttle drive system at one end of the throttle shaft. The return spring and the initial opening spring have the same mounting structure as that of the first embodiment.
[0110]
  At one end of the throttle shaft, the throttle gear 11 and the lever (B) 3 are fixedly arranged, and then the tip 38 with the initial opening spring 5 is fixedly arranged, and then the return spring 4 and the lever (A) 2 through the sleeve 45. The attached sleeve 42 is fitted and tightened by the nut 47. The sleeve 42 can rotate on the sleeve 45.
[0111]
  The return spring 4 has one end 4 </ b> A engaged with the pin 37 on the throttle body 15 side and the other end engaged with the sleeve 42.
[0112]
  The arm 3 </ b> A of the lever B (3) can be engaged with the lever (A) 2 beyond the initial opening spring 5 and the return spring 4.
[0113]
  One end 5A of the initial opening spring 5 is engaged with the arm 3A of the lever B (3), and the other end is engaged with the tip 38. In this example, the initial opening adjustment screw 6 and the fully closed position adjustment screw 7 are not shown, but these are arranged in a case portion 15 integral with the throttle body 15. Since the principle of the initial opening operation is the same as that of each of the embodiments described above, description thereof is omitted here.
[0114]
  In the present embodiment, the effects other than the limp home operation are substantially the same as those of the above-described embodiments, and further, the following effects are obtained in addition to the effect i in the fourth embodiment.
[0115]
  j. In this example, throttle shaft torque characteristics T1 (in other words, P1 characteristics) and T2 (in other words, P2 characteristics) at the position of the stopper for setting the initial opening are set as follows.
[0116]
[Equation 3]
                  T1 ≧ Mf × Ge + Vf
                  T2 ≦ Mf × Ge + Vf
  By setting in this way, the throttle shaft torque characteristics of T1 and T2 can be made as small as possible, and the throttle shaft torque step T1-(− T2) near the throttle initial opening position can be reduced. It can be planned. In the case of T2 <Mf × Ge + Vf, as shown in FIG. 16, T2 of the second urging means is somewhat sacrificed and a setting error occurs in the throttle initial opening position. If the air flow rate required for the cold start combustion required from the side can be secured, the intended purpose of the throttle initial opening can be achieved.
[0117]
  k. Further, in this example, the throttle body 15 is sandwiched, a reduction gear mechanism and an initial opening setting mechanism are arranged on one side, and a throttle position sensor 14 is arranged on the other side.
[0118]
  According to the above configuration, the gear mechanism and the throttle position sensor 14 are separated from each other via the throttle body 15. In general, wear powder is likely to be generated from a mechanical sliding portion (for example, a sliding portion between metals) such as a gear mechanism. However, the above-described isolation arrangement structure prevents the wear powder from entering the throttle position sensor 14, and the throttle position sensor. Can prevent performance degradation.
[0119]
  Further, by integrating the gear mechanism and the throttle initial opening setting mechanism in the motor-side casing 15A, it is possible to consolidate parts and reduce the overall size of the throttle device. Furthermore, the throttle position sensor 14 can be arranged as close to the center of the throttle body as possible, and as a result, the influence of the throttle shaft deflection and bending can be eliminated to reduce fluctuations in output characteristics.
[0120]
【The invention's effect】
  As described above, according to the present invention, the initial opening degree setting mechanism of the throttle valve or other mechanisms (for example, a limp home mechanism) as required is integrated and streamlined so that these mechanisms can be integrated. While reducing the friction on the mechanism and improving the characteristics of the urging means (for example, improving the spring characteristics of the return spring, etc.), the burden on the drive of the throttle actuator is reduced. Stabilization of the throttle control operation can be achieved.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a first embodiment of the present invention.
FIG. 2 is a view taken in the direction of arrow A in FIG.
FIG. 3 is a perspective view of the first embodiment.
FIG. 4 is a cross-sectional view of a main part of the first embodiment.
FIG. 5 is an explanatory diagram showing the operation principle of the present invention.
FIG. 6 is an explanatory diagram showing limp home characteristics of the first embodiment.
FIG. 7 is an explanatory diagram showing throttle shaft torque characteristics in the operating principle of the present invention.
FIG. 8 is a sectional view showing a second embodiment of the present invention.
FIG. 9 is an exploded perspective view showing the second embodiment.
FIG. 10 is a cross-sectional view of a main part showing the second embodiment.
FIG. 11 is an essential part cross-sectional view showing a third embodiment of the present invention.
FIG. 12 is an exploded perspective view of the third embodiment.
FIG. 13 is an exploded perspective view showing a fourth embodiment of the present invention.
FIG. 14 is a cross-sectional view of a main part showing the fourth embodiment.
FIG. 15 is a cross-sectional view showing a fifth embodiment of the present invention.
FIG. 16 is an explanatory diagram showing an example of throttle shaft torque characteristics according to the fifth embodiment.
[Explanation of symbols]
  1, 1 '... accelerator lever, 2 ... lever A (return lever), 3 ... lever B (throttle lever), 4 ... first urging means (return spring), 5 ... second urging means (initial opening) Spring), 6 ... initial opening adjusting screw (second stopper), 7 ... throttle fully closed position adjusting screw (first stopper), 8 ... accelerator spring, 9A, 9B, 10, 11 ... gear mechanism, DESCRIPTION OF SYMBOLS 12 ... Motor (throttle actuator), 13 ... Accelerator sensor, 14 ... Throttle sensor, 15 ... Throttle body, 18 ... Throttle shaft, 24 ... Throttle valve, 42 ... Sleeve (second sleeve), 45 ... Sleeve (second sleeve) Sleeve), 47 ... nut.

Claims (5)

Throttle body,
A throttle shaft rotatably attached to the throttle body;
A throttle valve provided on the throttle shaft;
A motor housed in the throttle body;
A fully closed position setting mechanism for setting a fully closed position of the throttle valve;
An initial opening setting mechanism for setting an initial opening position of the throttle valve when the motor is not energized to be larger than the fully closed position;
A reduction gear that decelerates and transmits the output of the motor to the throttle shaft;
An engine throttle device equipped with
The initial opening setting mechanism is:
A fitting member rotatably fitted to the throttle shaft;
First biasing means for biasing the fitting member in a closing direction of the throttle valve;
A stopper provided in the throttle body so as to prevent the fitting member from rotating in the closing direction from the initial opening position of the throttle valve;
A member fixed to the throttle shaft;
A second urging means that urges the fitting member and the member fixed to the throttle shaft to engage with each other;
The throttle shaft to which the motor output is transmitted from the motor via the reduction gear is attached in the closing direction by the first urging means when the throttle valve is located on the opening side from the initial opening position. When the force acts, and when the throttle valve is positioned closer to the closing position than the initial opening position, the biasing force in the opening direction by the second biasing means acts,
Thus, when the throttle shaft rotates across the initial opening position, it acts on the throttle shaft by the first and second urging means acting on the throttle shaft at the initial opening position. By switching the direction of the urging force, the urging force acting on the throttle shaft is configured to generate a torque step,
When the opening of the throttle valve is operated by the motor on the opening side from the initial opening position, the torque transmitted from the motor to the throttle shaft via the reduction gear and the first urging means The motor is controlled such that the opening of the throttle valve is controlled by balancing the torque acting on the throttle shaft,
When the throttle valve is operated by the motor closer to the closing position than the initial opening position, the motor is controlled to resist the urging force of the second urging means,
When the throttle valve opens and closes on the opening side from the initial opening position, a member fixed to the throttle shaft engages with the fitting member, so that the fitting member rotates integrally with the throttle shaft. An engine throttle device characterized by having a configuration . The engine throttle device according to claim 1,
A motor case portion for housing the motor is provided in the throttle body, and the motor is accommodated in the motor case portion so that the motor and the throttle shaft are arranged in parallel.
The reduction gear is composed of a motor gear provided on the motor shaft, a throttle gear attached to the throttle shaft, and an intermediate gear provided between the two gears,
The throttle device for an engine, wherein the throttle gear is disposed closer to a throttle body than the motor gear. The engine throttle device according to claim 2,
A shaft that supports the intermediate gear is supported by a throttle body,
The intermediate gear includes a first intermediate gear having a large diameter and a second intermediate gear having a small diameter.
The second intermediate gear is disposed closer to the throttle body than the first intermediate gear, the first intermediate gear and the motor gear mesh, and the second intermediate gear meshes with the throttle gear. Thus, the output of the motor is decelerated and transmitted to the first intermediate gear, transmitted to the second intermediate gear that rotates integrally with the first intermediate gear, and the second A throttle device for an engine, wherein the engine is further decelerated from the intermediate gear and transmitted to the throttle gear. The engine throttle device according to claim 2 or 3,
The fully-closed position setting mechanism has a fully-closed position adjusting screw, and has a structure in which a fully-closed opening degree is set by the throttle gear coming into contact with the fully-closed position adjusting screw. Throttle device. The engine throttle device according to claim 4,
The throttle device for an engine, wherein the throttle gear has a fan shape.

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