JPWO2014115767A1 - Engine with throttle device and engine-driven vehicle - Google Patents

Abstract

A throttle valve (24) provided in the intake passage (31) of the engine is provided. A throttle shaft (27) that rotates integrally with the valve body (28) of the throttle valve (24), a spring member that biases the valve body (28) in a closing direction, and a gear mechanism (25) on the throttle shaft (27). And a throttle valve drive motor (26) connected via A sensor (42) for detecting a rotation angle of a rotation shaft (43) different from the throttle shaft (27) in the gear mechanism (25), and a rotation angle θ2 of the throttle shaft (27) using a detection value of the sensor (42). And a throttle angle calculation unit. The throttle angle calculator calculates the rotation angle θ2 of the throttle shaft (27) by subtracting the backlash angle α from the detection angle of the sensor (42). It is possible to provide an engine with a throttle device that can detect the rotation angle of the throttle shaft with high accuracy while adopting a configuration in which the rotation angle of the rotation shaft different from the throttle shaft is detected by a sensor.

Description

  The present invention relates to an engine with a throttle device provided with a sensor for detecting the opening of a throttle valve and an engine-driven vehicle.

  As a conventional throttle device, for example, there is one described in Patent Document 1. The throttle device disclosed in Patent Document 1 includes a butterfly valve type throttle valve, a motor for driving the throttle valve, and a sensor for detecting the opening of the throttle valve.

The throttle valve includes a disc-shaped valve body and a throttle shaft that rotates integrally with the valve body.
The throttle shaft is connected to the output shaft of the motor via a gear mechanism. This gear mechanism decelerates the rotation of the motor and transmits it to the throttle shaft. The gear mechanism includes a drive gear provided on the output shaft, a driven gear provided on the throttle shaft, and a transmission gear meshing with these gears. The transmission gear is provided on an intermediate shaft located between the output shaft and the throttle shaft.
The sensor detects the rotation angle of the intermediate shaft.

  By the way, in a lightweight engine-driven vehicle such as a motorcycle, the power-to-weight ratio (weight per unit horsepower) becomes small, so that it is necessary to cause the throttle valve to accurately follow the accelerator operator. In order to realize this, the opening degree of the throttle valve (rotational angle of the throttle shaft) must be detected with high accuracy.

JP 2010-19137 A

  The throttle device described in Patent Document 1 has a problem that it is difficult to accurately determine the rotation angle of the throttle shaft. This is because the intermediate shaft for detecting the rotation angle by the sensor is connected to the throttle shaft via a gear. That is, since there is a backlash at the meshing portion of the gear, the rotation angle of the throttle shaft relative to the rotation angle of the intermediate shaft becomes uncertain.

  Such a problem can be solved to some extent by directly detecting the rotation angle of the throttle shaft with a sensor. However, if this configuration is adopted, a sensor must be disposed in the vicinity of the shaft end portion of the throttle shaft, so that a protrusion made of the sensor is formed on the side portion of the throttle device. That is, the new problem that a throttle device will enlarge will arise. Further, since the rotation angle of the throttle shaft is smaller than the rotation angle of the intermediate shaft, there arises a problem that the resolution of the rotation angle detected by the sensor is lowered.

  The present invention has been made to solve such a problem, and a throttle capable of detecting the rotation angle of the throttle shaft with high accuracy while adopting a configuration in which the rotation angle of the rotation shaft different from the throttle shaft is detected by a sensor. A first object is to provide an engine with a device. A second object of the present invention is to provide an engine-driven vehicle in which a throttle valve easily follows a throttle operator and is easy to drive.

  In order to achieve this object, an engine with a throttle device according to the present invention includes a throttle valve provided in an intake passage of the engine, a throttle shaft that rotates integrally with a valve body of the throttle valve, and a direction in which the valve body is closed. A spring member biased to the throttle shaft, a throttle valve driving motor coupled to the throttle shaft via a gear mechanism, a sensor for detecting a rotation angle of a rotation shaft different from the throttle shaft in the gear mechanism, and the sensor A throttle angle calculation unit that obtains the rotation angle of the throttle shaft using the detected value of the detected value, and the rotation angle of the rotation shaft detected by the sensor is set as a detection angle, and the rotation shaft is between the rotation shaft and the throttle shaft The rotation angle of the rotation shaft corresponding to the backlash included in the meshing portion of the provided gear is defined as the backlash angle, and the throttle angle calculation Is for calculating a rotation angle of the throttle shaft based on the rotation angle obtained by subtracting the backlash angle from the detected angle.

  An engine-driven vehicle according to the present invention is equipped with the engine with a throttle device according to the above-described invention.

  According to the present invention, the backlash included in the meshing portion of the gear located between the rotating shaft and the throttle shaft is substantially eliminated. For this reason, since the rotation shaft and the throttle shaft rotate substantially integrally, the rotation angle of the throttle shaft can be accurately obtained.

Therefore, according to the present invention, it is possible to provide an engine with a throttle device capable of detecting the rotation angle of the throttle shaft with high accuracy while adopting a configuration in which the rotation angle of the rotation shaft different from the throttle shaft is detected by the sensor. .
The engine-driven vehicle according to the present invention includes the throttle device described above, and the throttle valve follows the throttle operator with high accuracy, so that it is easy to drive.

FIG. 1 is a side view of a motorcycle equipped with an engine with a throttle device according to a first embodiment of the present invention. FIG. 2 is a perspective view showing the configuration of the throttle valve drive unit according to the first embodiment of the present invention. FIG. 3 is a side view showing a main part of the throttle device according to the first embodiment of the present invention. FIG. 4 is a side view of the valve gear according to the first embodiment of the present invention. FIG. 5 is an enlarged side view showing a meshing portion between the valve gear and the pinion gear according to the first embodiment of the present invention. FIG. 6 is a block diagram showing the configuration of the throttle angle calculation unit according to the first embodiment of the present invention. FIG. 7 is a flowchart for explaining a throttle angle calculation program according to the first embodiment of the present invention. FIG. 8 is a graph showing the relationship between the output value of the angle sensor and the rotation angle of the throttle shaft according to the first embodiment of the present invention. FIG. 9 is a flowchart for explaining the operation of the CPU according to the first embodiment of the present invention. FIG. 10 is a flowchart for explaining a throttle angle calculation program according to the second embodiment of the present invention. FIG. 11 is a flowchart for explaining the operation of the CPU according to the second embodiment of the present invention. FIG. 12 is a cross-sectional view for explaining a technique that serves as a reference of the present invention.

(First embodiment)
Hereinafter, an embodiment of an engine with a throttle device and an engine-driven vehicle according to the present invention will be described in detail with reference to FIGS. Here, an embodiment when the present invention is applied to a motorcycle will be described. The first embodiment is an embodiment of the invention described in claims 1 to 4 and claim 7.

  A motorcycle 1 shown in FIG. 1 is a vehicle in which an occupant (not shown) sits across a seat 2 and grips a steering handle 3 with an arm. Reference numeral 4 denotes a front wheel, 5 denotes a front fork, 6 denotes an engine, and 7 denotes a rear wheel. The steering handle 3 is provided with an accelerator operator (not shown) that is operated by an occupant.

The engine 6 is a four-cycle engine and includes a crankcase 11 and a cylinder body 12 and a cylinder head 13 mounted on the crankcase 11. The cylinder body 12 is attached to the crankcase 11 so that the axis thereof is directed to the front upper side of the motorcycle 1.
An intake pipe 14 is attached to the rear surface of the cylinder head 13. A throttle valve driving portion 22 of an electric throttle device 21 to be described later is attached to the upstream end portion of the intake pipe 14.

The throttle device 21 includes a throttle valve drive unit 22 shown in FIG. 2 and a throttle angle calculation unit 23 shown in FIG.
The throttle valve drive unit 22 includes a butterfly type throttle valve 24, a throttle valve drive motor 26 connected to the throttle valve 24 via a gear mechanism 25, and the like. In FIG. 2, members such as the throttle body are omitted, and only main members of the throttle valve drive unit 22 are illustrated. The throttle valve 24 includes a single throttle shaft 27 and a plurality of disc-shaped valve bodies 28 attached to the throttle shaft 27.

The throttle shaft 27 is rotatably supported by a throttle body (not shown) in a state extending in the vehicle width direction of the motorcycle 1. The throttle shaft 27 rotates integrally with the valve body 28. The throttle shaft 27 passes through a torsion coil spring 29 (see FIG. 3). The torsion coil spring 29 is for biasing the valve body 28 in the closing direction. One end of the torsion coil spring 29 is hung on a valve gear 30 attached to the throttle shaft 27, and the other end is hung on a throttle body. The throttle shaft 27 rotates integrally with the valve gear 30.
The valve body 28 is provided in the intake passage 31 as shown in FIG. The intake passage 31 extends from an air cleaner (not shown) into the cylinder head 13 through the throttle body and the intake pipe 14.

  As shown in FIG. 3, the gear mechanism 25 forms a two-stage gear reducer, and includes four gears including the valve gear 30. The four gears are a valve gear 30, a pinion gear 32 that meshes with the valve gear 30, a wheel gear 33 that rotates together with the pinion gear 32, and a motor gear 34 that meshes with the wheel gear 33. These gears are made of plastic. The pinion gear 32 and the wheel gear 33 are integrally formed so that one intermediate gear 35 is formed.

  The valve gear 30 is configured by a so-called sector gear and includes a fan-shaped gear forming portion 30a. The valve gear 30 includes a fully closed stopper 36 and a fully opened stopper 37 as shown in FIG. The fully closed stopper 36 is for setting the fully closed position of the throttle valve 24. As shown in FIG. 2, the fully closed stopper 36 is formed in an L-shaped cross section and is provided at one end of the gear forming portion 30a in the rotation direction. When the fully closed stopper 36 abuts on an adjustment bolt 38 (see FIG. 4) on the throttle body side, the rotation of the valve gear 30 in the direction in which the throttle valve 24 is closed is restricted.

The fully open stopper 37 is formed in a plate shape and stands on the valve gear 30 and is disposed at the other end of the gear forming portion 30a in the rotation direction. As shown by a two-dot chain line in FIG. 4, the fully open stopper 37 abuts against the pressure receiving wall 39 of the valve body, thereby restricting the rotation of the valve gear 30 in the direction in which the throttle valve 24 opens.
In other words, the valve gear 30 is designed from a fully closed position (fully closed abutting position) where the fully closed stopper 36 contacts the adjusting bolt 38 to a fully opened position (fully opened abutting position) where the fully opened stopper 37 contacts the pressure receiving wall 39. It can be rotated by a rotation angle θ1 (see FIG. 4).

  An intermediate gear 35 composed of a pinion gear 32 and a wheel gear 33 is fixed to one end of an intermediate shaft 40 (see FIGS. 2 and 3), and is rotatably supported by the throttle body via the intermediate shaft 40. Yes. The pinion gear 32 is provided at one end of the wheel gear 33 adjacent to the intake passage 31. As shown in FIG. 5, the pinion gear 32 can be rotated by the backlash angle α with respect to the valve gear 30 because there is a backlash at the meshing portion with the valve gear 30. In FIG. 5, the line indicated by reference numeral C <b> 1 is the pitch circle of the pinion gear 32, and the line indicated by reference numeral C <b> 2 is the pitch circle of the wheel gear 33.

  A ring magnet 41 is attached to the other end of the wheel gear 33 in the axial direction, as shown in FIGS. The ring magnet 41 is formed in a ring shape, and is fixed to the axial center of the wheel gear 33 so as to be positioned on the same axis as the wheel gear 33. The ring-shaped magnet 41 is magnetized so that the magnetic poles 41 a and 41 b (see FIG. 2) are divided into two by a virtual straight line orthogonal to the axis when viewed from the axial direction of the wheel gear 33.

  An angle sensor 42 is disposed at a position facing the ring magnet 41. The angle sensor 42 detects a rotation angle of a rotation shaft 43 including the intermediate gear 35 and the intermediate shaft 40, and is formed by a vector detection type Hall IC. In this embodiment, the angle sensor 42 constitutes a “sensor” in the present invention. The angle sensor 42 is supported by the throttle body in a state where a predetermined gap is formed between the angle sensor 42 and the ring-shaped magnet 41. That is, the angle sensor 42 detects a rotation angle of the rotation shaft 43 different from the throttle shaft 27 in the gear mechanism 25. A detection angle formed by the rotation angle of the rotation shaft 43 detected by the angle sensor 42 is sent as a signal to a throttle angle calculation unit 23 described later.

  The motor gear 34 is provided on the output shaft 44 of the throttle valve driving motor 26. That is, the rotation of the motor 26 is transmitted from the motor gear 34 to the valve gear 30 (throttle shaft 27) via the wheel gear 33 and the pinion gear 32. The motor 26 is supported by the throttle body. The operation of the motor 26 is controlled by a throttle angle calculator 23 described later.

  The throttle angle calculation unit 23 obtains the rotation angle of the throttle shaft 27 using the detected angle detected by the angle sensor 42, and operates the throttle shaft 27 so as to be interlocked with the accelerator operator. As shown in FIG. 6, the throttle angle calculation unit 23 according to this embodiment is configured by an ECU 54 (Electronic Control Unit) including a CPU 51, a nonvolatile memory 52, a motor driver 53, and the like.

The throttle angle calculation unit 23 is provided in a control device 55 (see FIG. 1) disposed below the seat 2 of the motorcycle 1. The control device 55 controls the operation of the engine 6 of the motorcycle 1.
The CPU 51 includes an AD (analog / digital converter) 56 that receives a signal. The AD 56 is connected to an angle sensor 42, an accelerator operation amount sensor 57, and the like. The accelerator operation amount sensor 57 detects the operation amount of the accelerator operation element and sends it to the AD 56 as a signal.

The non-volatile memory 52 is used for storing programs used by the CPU 51, numerical data calculated by the CPU 51, and the like. In this embodiment, the nonvolatile memory 52 corresponds to a “storage device” in the present invention. The motor driver 53 is for driving the throttle valve driving motor 26.
The CPU 51 according to this embodiment calculates the rotation angle of the throttle shaft 27 using a throttle angle calculation program described later.

By executing the throttle angle calculation program, the rotation angle θ2 of the throttle shaft 27 is calculated by calculation using the detection angle of the angle sensor 42, the backlash angle α, the design rotation angle θ1, and the like.
The CPU 51 sets the motor driver 53 so that the difference between the rotation angle θ2 of the throttle shaft 27 calculated by executing this throttle angle calculation program and the target rotation angle θ3 corresponding to the operation amount of the accelerator operator becomes zero. A control signal is sent to operate the throttle valve driving motor 26.

The throttle angle calculation program is configured as shown in the flowchart of FIG. 7 and is recorded in the nonvolatile memory 52. The CPU 51 reads the throttle angle calculation program from the nonvolatile memory 52 and uses it as necessary.
The throttle angle calculation program according to this embodiment is configured to calculate the rotation angle θ2 of the throttle shaft 27 after calculating the actual backlash angle α. The time for calculating the backlash angle α may be at the time of factory shipment or when the power is turned on.

  The backlash angle α is calculated in steps S1 to S3 in the flowchart shown in FIG. 7, and the rotation angle θ2 of the throttle shaft 27 is calculated in step S4. In step S1, first, the CPU 51 causes the throttle valve driving motor 26 to close the throttle valve 24. Then, the CPU 51 acquires the output value A of the angle sensor 42 in a state where the throttle valve 24 is in the fully closed butting position. The fully closed butting position is the position of the throttle valve 24 when the fully closed stopper 36 comes into contact with the adjustment bolt 38.

  In step S 2, first, the CPU 51 opens the throttle valve 24 by the throttle valve driving motor 26. Next, the CPU 51 acquires the output value B of the angle sensor 42 in a state where the throttle valve 24 is in the fully open butting position. The fully open butting position is the position of the throttle valve 24 where the fully open stopper 37 contacts the pressure receiving wall 39 of the throttle body. The rotation angle θ2 of the throttle shaft 27 is increased as shown in FIG. 8 by operating the throttle valve 24 from the fully closed butting position to the fully opening butting position in this way.

  The horizontal axis of FIG. 8 indicates the output value of the angle sensor 42, and the vertical axis indicates the rotation angle θ2 of the throttle shaft 27. When the motor 26 is operated as described above, the throttle shaft 27 starts rotating after the output value of the angle sensor 42 is increased from the output value A by the amount of backlash and becomes the output value C. That is, the output value of the angle sensor 42 acquired at the fully-opened abutting position is a value including backlash.

  After the throttle valve 24 is opened to the fully open butting position, in step S3, the CPU 51 subtracts a second operating angle from a first operating angle described later to obtain a backlash angle α. The first operating angle is a rotation angle of the throttle valve 24 including backlash. This “rotation angle of the throttle valve 24 including backlash” is determined by the motor 26 driving the throttle valve 24 from the output value B of the angle sensor 42 when the throttle valve 24 is fully opened by the motor 26 driving. Can be obtained by subtracting the output value A of the angle sensor 42.

The second operating angle is the true rotation angle of the throttle valve 24, which is the rotation angle θ2 of the throttle shaft 27 when the valve body 28 of the throttle valve 24 is moved from the fully closed position to the fully open position. As the second operation angle, a design value such as the design rotation angle θ1 shown in FIG. 4 or an actual measurement value measured by actually operating the throttle valve 24 can be used.
When step S3 is performed, the backlash angle α corresponding to the difference between the output value C and the output value A in FIG. In step S <b> 3, the CPU 51 stores the backlash angle α calculated as described above in the nonvolatile memory 52.

Next, in step S4, the CPU 51 calculates the rotation angle θ2 of the throttle shaft 27 based on the rotation angle obtained by subtracting the backlash angle α from the detection angle of the angle sensor 42. The detection angle is a rotation angle of the rotation shaft 43 detected by the angle sensor 42.
The CPU 51 according to this embodiment performs steps S1 to S3 at the time of shipment from the factory, and performs step S4 after turning on the power. The backlash angle α used when executing step S4 is read from the nonvolatile memory 52 and used. After the power is turned on, the CPU 51 operates based on the operation program shown in the flowchart of FIG.

  That is, the CPU 51 reads the backlash angle α from the nonvolatile memory 52 in step P2 after power is turned on in step P1 of the flowchart shown in FIG. And CPU51 acquires the present rotation angle of the rotating shaft 43, ie, a detection angle, using the angle sensor 42 in step P3.

  Next, in step P4, the CPU 51 determines whether or not the detected angle is smaller than the backlash angle α. In other words, the CPU 51 determines whether or not the rotation angle of the rotation shaft 43 detected by the angle sensor 42 is a rotation angle between the rotation angle when the throttle is fully closed and the backlash angle α. If this determination is YES, that is, if the detected angle is smaller than the backlash angle α, the process proceeds to step P5, where the CPU 51 sets the rotation angle θ2 of the throttle shaft 27 as the rotation angle when the throttle is fully closed.

On the other hand, when the detected angle is equal to or larger than the backlash angle α, the process proceeds to Step P6, and Step S4 described above is performed. That is, in step P6, the CPU 51 calculates the rotation angle θ2 of the throttle shaft 27 based on the value obtained by subtracting the backlash angle α from the detection angle.
Thereafter, in step P7, the CPU 51 operates the motor 26 so that the rotation angle θ2 of the throttle shaft 27 coincides with the target rotation angle.
Steps P3 to P7 are repeated until the power is turned off in Step P8.

According to the engine with the throttle device configured as described above, the backlash included in the meshing portion of the gear located between the rotating shaft 43 and the throttle shaft 27 is substantially removed. For this reason, since the rotating shaft 43 and the throttle shaft 27 rotate substantially integrally, the rotation angle θ2 of the throttle shaft 27 can be accurately obtained.
Therefore, according to this embodiment, the throttle device capable of detecting the rotation angle θ2 of the throttle shaft 27 with high accuracy while adopting the configuration in which the angle sensor 42 detects the rotation angle of the rotation shaft 43 different from the throttle shaft 27. It is possible to provide an engine with a mark.

When the rotation angle of the rotary shaft 43 detected by the angle sensor 42 is a rotation angle between the rotation angle when the throttle is fully closed and the backlash angle α, the throttle angle calculation unit 23 according to this embodiment The rotation angle θ2 of the throttle shaft 27 is the rotation angle when the throttle is fully closed.
Therefore, according to this embodiment, it is possible to accurately detect that the throttle valve 24 is fully closed.

The throttle angle calculation unit 23 according to this embodiment subtracts the second operating angle of the true throttle valve 24 from the first operating angle of the throttle valve 24 including the backlash obtained based on the detection value of the angle sensor 42. By doing so, the backlash angle α is calculated.
Therefore, according to this embodiment, since the backlash is obtained by subtracting the second operating angle not including the backlash from the first operating angle including the backlash of the meshing portion of the gear, the backlash angle is obtained. α can be calculated easily and accurately by calculation.

In this embodiment, a non-volatile memory 52 that stores the backlash angle α calculated by the throttle angle calculator 23 is provided. The throttle angle calculation unit 23 according to this embodiment calculates the backlash angle α at the time of factory shipment and stores it in the nonvolatile memory 52, and thereafter uses the backlash angle α read from the nonvolatile memory 52 during engine operation. Thus, the rotation angle θ2 of the throttle shaft 27 is calculated.
Therefore, according to this embodiment, it is not necessary to calculate the backlash angle α every time the power is turned on. That is, according to this embodiment, it is possible to provide an engine with a throttle device that can be quickly started.

  The motorcycle 1 according to this embodiment includes the throttle device 21 described above, and the throttle valve 24 follows the throttle operator with high accuracy, so that it is easy to drive.

(Second Embodiment)
The throttle angle calculation program and the operation program can be configured as shown in FIGS. 10 and 11, the same or equivalent members as those described with reference to FIGS. 1 to 9 are denoted by the same reference numerals, and detailed description thereof is omitted as appropriate.

Although the details of the throttle angle calculation program according to this embodiment will be described later, the rotation shaft 43 is rotated until the teeth of the pinion gear 32 contact the teeth of the valve gear 30, and the backlash angle α is detected based on the rotation angle at this time. The structure to do is taken.
The CPU 51 of the throttle angle calculation unit 23 according to this embodiment causes the throttle valve drive motor 26 to close the throttle valve 24 in step S1 of the flowchart shown in FIG. Then, the CPU 51 acquires the output value A of the angle sensor 42 in a state where the throttle valve 24 is in the fully closed butting position. In this embodiment, the output value A corresponds to the “first output value” in the invention described in claim 5.

  Next, in step S <b> 20, the CPU 51 acquires the output value D of the angle sensor 42 in a state where the rotation shaft 43 is in a control fully closed position described later. The control fully closed position is the position of the rotary shaft 43 when the pinion gear 32 is rotated by the backlash with respect to the valve gear 30. In order to position the rotary shaft 43 at the control fully closed position, a predetermined minute torque is applied to the throttle shaft 27 by the throttle valve driving motor 26.

  Here, the predetermined minute torque is a torque smaller than the initial torque of the torsion coil spring 29. That is, the torque is such that only the rotating shaft 43 rotates without the throttle shaft 27 rotating against the spring force of the torsion coil spring 29. Thus, by applying a minute torque to the rotating shaft 43, the rotating shaft 43 rotates by the amount of backlash. The output value D is a detection angle of the angle sensor 42 when the rotating shaft 43 rotates in this way. In this embodiment, the output value D corresponds to the “second output value” in the invention described in claim 5.

  Next, in step S30, the CPU 51 calculates the backlash angle α by subtracting the output value A (first output value) from the output value D (second output value). Thereafter, the CPU 51 calculates the rotation angle θ2 of the throttle shaft 27 in step S4 as in the first embodiment.

  The throttle angle calculation program shown in FIG. 10 is incorporated in the operation program shown in FIG. 11 and is executed after the power is turned on. That is, after the power is turned on in step P1 of the flowchart shown in FIG. 11, the CPU 51 performs step S1, step S20, and step S30 of the throttle angle calculation program to obtain the backlash angle α. The backlash angle α is stored in the nonvolatile memory 52 by the CPU 51.

Then, in step P2, the CPU 51 reads the backlash angle α from the nonvolatile memory 52, and in step P3, acquires the current rotation angle of the rotation shaft 43, that is, the detection angle, using the angle sensor 42.
Next, in step P4, the CPU 51 determines whether or not the detected angle is smaller than the backlash angle α. In other words, the CPU 51 determines whether or not the rotation angle of the rotation shaft 43 detected by the angle sensor 42 is a rotation angle between the rotation angle when the throttle is fully closed and the backlash angle α.

If this determination is YES, that is, if the detected angle is smaller than the backlash angle α, the process proceeds to step P5, where the CPU 51 sets the rotation angle θ2 of the throttle shaft 27 as the rotation angle when the throttle is fully closed.
On the other hand, when the detected angle is equal to or larger than the backlash angle α, the process proceeds to Step P6, and Step S4 described above is performed. That is, in step P6, the CPU 51 calculates the rotation angle θ2 of the throttle shaft 27 based on the value obtained by subtracting the backlash angle α from the detection angle.

Thereafter, in step P7, the CPU 51 operates the motor 26 so that the rotation angle θ2 of the throttle shaft 27 coincides with the target rotation angle.
The operation program according to this embodiment is repeatedly executed until the power is turned off in Step P8. That is, the CPU 51 calculates the rotation angle θ2 of the throttle shaft 27 using the backlash angle α read from the nonvolatile memory 52 until the power is turned off.

The CPU 51 of the throttle angle calculation unit 23 according to this embodiment detects the first output value (output value A) of the angle sensor 42 when the throttle valve 24 is fully closed by driving by the throttle valve driving motor 26. To do. Further, the CPU 51 applies the second output value (output) of the angle sensor 42 when a torque smaller than the initial torque of the torsion coil spring 29 is applied to the throttle shaft 27 in the direction in which the throttle valve 24 opens by the throttle valve driving motor 26. The value D) is detected. Then, the CPU 51 calculates the backlash angle α by subtracting the first output value from the second output value.
Therefore, according to this embodiment, since the backlash angle α can be calculated each time the power is turned on, the increase in the backlash angle α due to secular change is also removed, and the rotation angle θ2 of the throttle shaft 27 is removed. Can be determined more accurately.

In this embodiment, a non-volatile memory 52 that stores the backlash angle α calculated by the throttle angle calculator 23 is provided. The throttle angle calculator 23 calculates the backlash angle α when the power is turned on and stores it in the nonvolatile memory 52. Further, the throttle angle calculator 23 calculates the rotation angle θ2 of the throttle shaft 27 using the backlash angle α read from the nonvolatile memory 52 until the power is turned off.
For this reason, in this embodiment, when the engine 6 is operated, the backlash angle α can be calculated only once when the power is turned on. Therefore, according to this embodiment, it is possible to provide an engine with a throttle device that does not wastefully calculate the backlash angle α during operation.

(Reference technology)
The rotation shaft 43 whose rotation angle is detected by the angle sensor 42 can be formed as shown in FIG. 12, members identical or equivalent to those described with reference to FIGS. 1 to 11 are given the same reference numerals, and detailed description thereof is omitted as appropriate.

  The pinion gear 32 of the rotating shaft 43 shown in FIG. 12 includes a fixed portion 61 formed integrally with the wheel gear 33, a movable portion 62 that can rotate with respect to the fixed portion 61, and the movable portion 62 that is fixed to the fixed portion 61. And a torsion coil spring 63 that is urged in one direction. The movable portion 62 is rotatably supported by the intermediate shaft 40 while being aligned with the fixed portion 61 in the axial direction.

  According to this embodiment, since the pinion gear 32 constitutes a so-called scissor gear, errors due to backlash can be eliminated. Unlike the case where the scissor gear is used in this way, the throttle device 21 shown in the first and second embodiments can obtain the same effect using a simple gear. Therefore, by adopting the first and second embodiments, it is possible to keep the manufacturing cost low as compared with the case where the scissor gear is used.

  In each of the above-described embodiments, the example in which the present invention is applied to a motorcycle has been described. However, the present invention can be applied to any vehicle provided with an engine having a throttle device. The present invention can be applied to, for example, a scooter, an automatic tricycle, an automatic four-wheel vehicle, a rough terrain vehicle, a snow vehicle, and a small planing boat.

  DESCRIPTION OF SYMBOLS 1 ... Motorcycle 1, 6 ... Engine, 21 ... Throttle device, 23 ... Throttle angle calculating part, 24 ... Throttle valve, 25 ... Gear mechanism, 26 ... Motor for driving a throttle valve, 28 ... Valve body, 27 ... Throttle shaft, DESCRIPTION OF SYMBOLS 29 ... Torsion coil spring (spring member), 31 ... Intake passage, 42 ... Angle sensor, 43 ... Rotating shaft, (alpha) ... Backlash angle.

Claims (7)

A throttle valve provided in the intake passage of the engine;
A throttle shaft that rotates integrally with the valve body of the throttle valve;
A spring member for urging the valve body in a closing direction;
A throttle valve driving motor connected to the throttle shaft via a gear mechanism;
A sensor for detecting a rotation angle of a rotation shaft different from the throttle shaft in the gear mechanism;
A throttle angle calculation unit for obtaining a rotation angle of the throttle shaft using a detection value of the sensor,
The rotation angle of the rotating shaft detected by the sensor is a detection angle,
The rotation angle of the rotation shaft corresponding to the backlash included in the meshing portion of the gear provided between the rotation shaft and the throttle shaft is a backlash angle,
The engine with a throttle device, wherein the throttle angle calculation unit calculates a rotation angle of the throttle shaft based on a rotation angle obtained by subtracting the backlash angle from the detection angle.   2. The engine with a throttle device according to claim 1, wherein the throttle angle calculation unit is configured such that a rotation angle of the rotation shaft detected by the sensor is a rotation angle between a rotation angle when the throttle is fully closed and the backlash angle. In this case, the engine with a throttle device is characterized in that the rotation angle of the throttle shaft is the rotation angle when the throttle is fully closed. 3. The engine with a throttle device according to claim 1, wherein the throttle angle calculation unit calculates a true throttle valve from a first operating angle of the throttle valve including a backlash obtained based on a detection value of the sensor. Calculating the backlash angle by subtracting a second operating angle;
The first operating angle is determined based on the output value of the sensor when the throttle valve is fully opened by driving by the throttle valve driving motor, and the throttle valve is fully closed by driving by the throttle valve driving motor. The rotation angle of the throttle shaft obtained by subtracting the output value of the sensor when
The engine with a throttle device, wherein the second operating angle is a rotation angle of the throttle shaft based on a design value or an actual measurement value when the valve body of the throttle valve is moved from a fully closed position to a fully open position. . The engine with a throttle device according to claim 3, further comprising a storage device that stores the backlash angle calculated by the throttle angle calculation unit,
The throttle angle calculation unit calculates the backlash angle at the time of factory shipment, stores it in the storage device, and rotates the throttle shaft using the backlash angle read from the storage device during subsequent engine operation. An engine with a throttle device, characterized in that the angle is calculated. The engine with a throttle device according to claim 1 or 2, wherein the throttle angle calculation unit includes:
A first output value of the sensor when the throttle valve is fully closed by driving by the throttle valve driving motor;
Detecting a second output value of the sensor when a torque smaller than an initial torque of the spring member is applied to the throttle shaft in a direction in which the throttle valve opens by a throttle valve driving motor;
The engine with a throttle device, wherein the backlash angle is calculated by subtracting the first output value from the second output value. The engine with a throttle device according to claim 5, further comprising a storage device for storing the backlash angle calculated by the throttle angle calculation unit,
The throttle angle calculation unit calculates the backlash angle when the power is turned on, stores it in the storage device, and rotates the throttle shaft using the backlash angle read from the storage device until the power is turned off. An engine with a throttle device, characterized in that the angle is calculated.   An engine-driven vehicle on which the engine with a throttle device according to any one of claims 1 to 6 is mounted.

Images