JP7330982B2 - Electronic control throttle device for engine - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronically controlled throttle device that opens and closes a throttle valve with a motor and detects the degree of opening of the throttle with an inductive throttle sensor.

In the conventional throttle device, which mechanically drives the throttle valve to open and close via an accelerator wire, the relationship between the accelerator operation amount and the throttle opening is uniquely determined, so there is room for improvement in terms of engine performance and exhaust gas characteristics. was there. Therefore, an electronically controlled throttle device has been put into practical use, in which a motor drives a throttle valve to open and close based on a target throttle opening calculated from an accelerator operation amount or the like. In order for this type of throttle device to function, it is necessary to compare the target throttle opening with the actual throttle opening. is equipped with a throttle sensor.

FIG. 8 is a cross-sectional view showing the throttle device of Patent Document 1. As shown in FIG. A throttle shaft 6 is arranged in the valve body 3 of the casing 2 of the throttle device 101 so as to traverse the inside of the cylindrical throttle bore 3a, and the engine is throttled according to the change in the opening of the throttle valve 8 connected to the throttle shaft 6. Air intake to is regulated. A gear housing chamber 4 is formed adjacent to the valve body 3 and sealed with a cover (not shown). A driven gear 14 is fixed in the gear housing chamber 4 with one end of a throttle shaft 6 projecting therefrom.

A motor 15 is attached to one side of the valve body 3 , and an output shaft 15 a of the motor 15 protrudes into the gear housing chamber 4 to which a drive gear 16 is fixed. are engaged. Therefore, the rotation of the motor 15 is transmitted to the throttle shaft 6 while being decelerated through the drive gear 16, the intermediate gear 17 and the driven gear 14, and the throttle valve 8 is driven to open and close in accordance with the rotational direction of the motor 15.

The inductive throttle sensor 102 as a whole consists of a rotor 103 provided with excitation conductors and a substrate 104 provided with excitation conductors and signal detection conductors. The rotor 103 is supported from the side surface of the driven gear 14 via a support stand 105, and the substrate 104 is attached to the inner surface of the cover of the gear housing chamber 4. As a result, excitation conductors on the rotor 103 side, excitation conductors on the substrate 104 side and The signal detection conductors are opposed to each other.

An alternating current is supplied to the excitation conductors of the substrate 104 by an external power supply, and a current is excited in the excitation conductors of the rotor 103 accordingly. An alternating current is excited in the signal detection conductor by the excited current, and a throttle opening signal correlating with the rotation angle of the rotor 103 and thus the throttle opening is generated based on this alternating current.

JP 2017-173089 A

Although the throttle device of Patent Document 1 is configured as described above, there is a problem that it is difficult to reduce the size of the throttle device due to the wasted space around the throttle sensor 102 .

That is, in order to generate the current excitation action as described above, the excitation conductor, the excitation conductor, and the signal detection conductor must be opposed to each other with a minute gap therebetween. However, since the side surface of the driven gear 14 is separated from the substrate 104 provided on the cover in the throttle axial direction along the axis L1 of the throttle shaft 6, the rotor 103 is attached directly to the side surface of the driven gear 14. In some cases, the excitation conductors cannot be held in place. Therefore, in the technique of Patent Document 1, the rotor 103 is raised by the support stand 105 to approach the substrate 104. As a result, the outer dimension of the throttle device 101 in the throttle axial direction is equivalent to the height H of the support stand 105. increases.

As a countermeasure for such a problem, it is conceivable to reduce the height of the support stand 105 to bring the rotor 103 closer to the driven gear 14, and to bring the substrate 104 closer to the driven gear 14 while maintaining a gap with the rotor 103. . However, in this case, the substrate 104 and the intermediate gear 17 overlap each other in the throttle axis direction and interfere with each other. necessary countermeasures. Since it is necessary to change the position of the rotor 103 together with the substrate 104, as a result, all the members on the throttle shaft 6 and the coaxial shaft 6 are separated from the axis L2 of the intermediate gear 17, and the gears are arranged in the direction in which they are arranged. The external dimensions of the throttle device 101 increase in the corresponding gear train direction.

As described above, since it is difficult to downsize the throttle device 101 of Patent Document 1, it is of course suitable for a two-wheeled vehicle that has little room for installing the throttle device, and for a four-wheeled vehicle that has a relatively large room for installation. Further miniaturization has been demanded even when applied to

SUMMARY OF THE INVENTION The present invention has been made in order to solve such problems. An object of the present invention is to provide an electronically controlled throttle device for an engine capable of achieving miniaturization by reducing the outer dimensions in both the axial direction of the throttle and the direction of the gear train while ensuring the detection function of the throttle opening.

In order to achieve the above object, the electronically controlled throttle device for an engine of the present invention transmits the rotation of a motor from a driving gear to a driven gear via an intermediate gear, and transmits the rotation of the casing via a throttle shaft connected to the driven gear. A throttle sensor comprising a substrate on which an excitation conductor and a signal detection conductor are arranged so as to oppose an excitation conductor that rotates with a throttle shaft while opening and closing a throttle valve in a throttle bore formed in a valve body. , the intermediate gear consists of a large-diameter input gear that meshes with the drive gear, and a small-diameter output gear that meshes with the driven gear. The conductor forming surface, which is the formed surface, comes close to the input gear of the intermediate gear through a small gap for contact prevention, and the excitation conductor and the signal detection conductor move along with the rotation of the throttle shaft. is positioned on the substrate so as to form a fan shape centered on the axis of the throttle shaft so as to correspond to the angular region where the position of the A first relief portion that forms a predetermined minute gap with respect to the conductor forming surface of the driven gear in the throttle axis direction, is disposed in a positional relationship that overlaps with the intermediate gear, and avoids interference with the intermediate gear. The first relief portion is formed in an arc shape corresponding to the outer periphery of the intermediate gear while leaving the formation regions of the excitation conductor and the signal detection conductor on the substrate (claim 1). ).
In another aspect, the excitation conductor and the signal detection conductor are formed in a fan shape in an area of 60 degrees in both directions across the axis of the throttle shaft in the flow direction of the intake air flowing through the throttle bore, for a total of 120 degrees, Further, all the regions are located on the opposite side of the intermediate gear from the axis of the throttle shaft (Claim 2).
As another aspect, the board is characterized in that surplus areas are formed on both sides of the axis of the throttle shaft in the flow direction of the intake air flowing through the throttle bore, and electronic components of the throttle sensor control circuit are mounted in the surplus areas. (Claim 3).

As another aspect, the valve body is provided with a connecting portion at the end of a tubular throttle bore extending in the air flow direction, the motor is arranged adjacent to the throttle bore, and the gear housing chamber of the casing is provided. , a drive gear, an intermediate gear, and a driven gear are housed inside, and it extends to one side along the gear train direction orthogonal to the air intake flow direction to provide a dead space between it and the connecting portion of the valve body. a terminal connecting portion extending from the first relief portion to a portion of the substrate on the connecting portion side of the valve body, and a power supply terminal and a signal output terminal facing the dead space in the terminal connecting portion; It is preferable that the connector is provided with terminals (Claim 4 ).

As another aspect, the gear housing chamber of the casing accommodates the driving gear, the intermediate gear and the driven gear inside, and has a cover provided in an opening opened to one side and fastened with bolts at the four corners. It is preferable that the substrate is formed with a second escape portion by notching the corners so as to avoid the two fastening points on the driven gear side (Claim 5 ).
As another aspect, it is preferable that the excitation conductor is provided directly on the driven gear (claim 6 ).

According to the electronically controlled throttle device for an engine of the present invention, the excitation conductor, the excitation conductor, and the signal detection conductor constituting the throttle sensor are opposed to each other at regular positions to ensure a good throttle opening detection function, Downsizing can be achieved by reducing the external dimensions in both the throttle axial direction and the gear train direction.

1 is a perspective view showing an electronically controlled throttle device for an engine according to an embodiment; FIG. FIG. 3 is an exploded perspective view showing the electronically controlled throttle device with the cover and substrate removed; FIG. 3 is a cross-sectional view taken along the line III-III of FIG. 2 showing the electronically controlled throttle device; FIG. 4 is a cross-sectional view taken along line IV-IV of FIG. 3 showing an electronically controlled throttle device; 4 is a view in the direction of arrow A in FIG. 3; FIG. 4 is a partially enlarged cross-sectional view of FIG. 3 showing details around the throttle sensor; FIG. 6 is a diagram corresponding to FIG. 5 showing another example in which the formation regions of the excitation conductors and signal detection conductors on the substrate are changed; FIG. FIG. 4 is a cross-sectional view corresponding to FIG. 3 showing the electronically controlled throttle device of Patent Document 1;

An embodiment in which the present invention is embodied in an electronically controlled throttle device for a motorcycle engine having a single throttle bore (hereinafter also simply referred to as a throttle device) will be described below.

1 is a perspective view showing the electronically controlled throttle device for the engine of this embodiment, FIG. 2 is an exploded perspective view showing the electronically controlled throttle device with the cover and the substrate removed, and FIG. 3 is III of FIG. 2 showing the electronically controlled throttle device FIG. 4 is a cross-sectional view taken along line IV-IV of FIG. 3, showing the electronically controlled throttle device.

As shown in FIG. 2, the casing 2 of the throttle device 1 comprises a valve body 3 having a tubular throttle bore 3a and a gear housing chamber 4 in which a gear train is housed. 4 is integrally molded by aluminum die casting. Note that the material of the casing 2 is not limited to this and can be changed arbitrarily.

As shown in FIGS. 3 and 4, four flanges 3b with bolt holes 3c are formed around the throttle bore 3a of the valve body 3, and the throttle device 1 is mounted by bolts (not shown) through the respective bolt holes 3c. is mounted on the engine manifold. The other end of the valve body 3 protrudes to one side (lower side in FIG. 4) as a cylindrical hose connecting portion 3d to which a hose from an air cleaner (not shown) is connected. This hose connection portion 3d functions as the connection portion of the present invention. When assembled to the engine, the throttle bore 3a serves as a part of the intake passage to guide intake air into the engine.

A throttle shaft 6 is disposed in the valve body 3 so as to traverse the inside of the throttle bore 3a, and both ends of the throttle shaft 6 are rotatably supported by bearings 7. As shown in FIG. Hereinafter, the direction along the axis L1 of the throttle shaft 6 will be referred to as the throttle axial direction. Inside the throttle bore 3a, a throttle valve 8 is connected to the throttle shaft 6 by a screw 9. As the throttle shaft 6 rotates, the opening degree of the throttle valve 8 is changed to adjust the intake air flowing through the throttle bore 3a. be.

As shown in FIGS. 2 and 3, one end of the throttle shaft 6 protrudes into a gear housing chamber 4 formed adjacent to the valve body 3. The gear housing chamber 4 has a substantially rectangular shape that opens toward one side. Female threads 4b are formed on flanges 4a formed at the four corners. A substantially rectangular cover 10 is provided over the opening of the gear housing chamber 4, and bolts 11 are screwed into female threads 4b of the gear housing chamber 4 through bolt holes 10a provided through the four corners. . As a result, the cover 10 is fastened to seal the gear housing chamber 4, and the bolt 11 functions as a fastening member of the present invention.

A torsion spring 13 is disposed in the gear housing chamber 4 so as to surround the throttle shaft 6 , and a driven gear 14 is fixed to the end of the throttle shaft 6 . As shown in FIG. 2, the driven gear 14 has a fan-like shape corresponding to the angle range required for opening and closing the throttle valve 8. As the driven gear 14 rotates, a full-open stopper (not shown) provided in the gear housing chamber 4 and a full-open stopper (not shown) are provided in the gear chamber 4. They respectively abut on the closing stoppers, thereby restricting the opening of the throttle valve 8 between the fully open position and the fully closed position.

Although not shown, one end of the torsion spring 13 is hooked on the driven gear 14 and the other end of the torsion spring 13 is hooked on the casing 2, thereby allowing the throttle valve 8 to move between the fully open position and the fully closed position. Forced to open. When the throttle valve 8 cannot be driven due to a failure of the motor 15, which will be described later, the throttle valve 8 is held at a predetermined opening by the torsion spring 13, and the amount of intake air required for vehicle running in the limp home mode, and thus the engine output. is ensured.
However, the biasing state of the torsion spring 13 is not limited to this, and may be biased to the fully closed position of the throttle valve 8, for example.

As shown in FIG. 3, a motor 15 is mounted on one side of the valve body 3 adjacent to the throttle bore 3a. there is An intermediate gear 17 is rotatably supported by a gear shaft 18 between the driving gear 16 and the driven gear 14 in the gear housing chamber 4. The intermediate gear 17 has a large-diameter input gear 17a and a small-diameter output gear 17b. integrally formed. An input gear 17 a of the intermediate gear 17 meshes with the drive gear 16 and an output gear 17 b of the intermediate gear 17 meshes with the driven gear 14 .

Therefore, the rotation of the motor 15 is transmitted to the throttle shaft 6 while being decelerated through the drive gear 16, the intermediate gear 17 and the driven gear 14, and the throttle valve 8 is driven to open and close in accordance with the rotational direction of the motor 15. Hereinafter, the direction in which the gears are arranged will be referred to as the gear train direction, and as a result, the gear train direction, the intake air flow direction, and the throttle axis direction are orthogonal to each other.

The throttle device 1 configured as described above is provided with an inductive throttle sensor 20 for detecting the opening degree of the throttle valve 8 . The throttle sensor 20 includes a rotor provided with excitation conductors and a substrate provided with excitation conductors and signal detection conductors. In this embodiment, the driven gear 14 functions as the rotor.

5 is a view in the direction of arrow A in FIG. 3, and FIG. 6 is a partially enlarged cross-sectional view of FIG. 3 showing details around the throttle sensor 20. In FIG. clearly shown.
As shown in FIGS. 5 and 6, the driven gear 14 is formed by manufacturing a disk-shaped core metal 14a and an excitation conductor 21 of a predetermined shape in advance, and insert-molding these members 14a and 21 from a synthetic resin material. . With the excitation conductor 21 directed toward the cover 10, one end of the throttle shaft 6 is inserted into the shaft hole 14b of the core metal 14a of the driven gear 14 and fixed by caulking. is designed to rotate.

On the other hand, a substrate 22 is fixed to the inner surface of the cover 10 in the gear housing chamber 4 , and an excitation conductor 23 and a signal detection conductor 24 are provided on the surface of the substrate 22 facing the driven gear 14 . As a result, the excitation conductor 21 on the driven gear 14 side and the excitation conductor 23 and signal detection conductor 24 on the substrate 22 side face each other with a minute gap therebetween. 22 a is a positioning hole for positioning the substrate 22 with respect to the cover 10 .

Since the principle of the inductive throttle sensor is well known, for example, from Patent Document 1 or Japanese Patent No. 4809829, only an outline will be described. An alternating current is supplied to the excitation conductor 23 of the substrate 22 by power supply from the outside, and the excitation conductor 21 of the driven gear 14 is accordingly excited by the current. An alternating current is excited in the signal detection conductor 24 of the substrate 22 by the excited current, and based on this alternating current, a control circuit 26, which will be described later, outputs a throttle opening signal correlating with the rotational angle of the driven gear 14 and thus the throttle opening. generated.

In the throttle device 101 of Patent Document 1 shown in FIG. 8 which is equipped with the throttle sensor 102 as described above, the rotor 103 is positioned with a small gap with respect to the substrate 104 as described in [Problems to be Solved by the Invention]. The rotor 103 is raised by a support stand 105 from above the driven gear 14 to approach the substrate 104 so that the rotor 103 is opposed to the driven gear 14 . Therefore, there is a problem that the outer dimension of the throttle device 101 in the throttle axial direction increases.
As a countermeasure, it is conceivable to reduce the height of the support stand 105 so that the substrate 104 as well as the rotor 103 approaches the driven gear 14 . However, since the substrate 104 and the intermediate gear 17 are arranged in a positional relationship in which they overlap each other in the throttle axis direction, it becomes necessary to separate the substrate 104 and the throttle shaft 6 from the axis L2 of the intermediate gear 17 in order to avoid interference. The outside dimension of the throttle device 101 in the gear train direction increases.

In view of the above problems, the inventor of the present invention paid attention to the formation area of the excitation conductor 23 and the signal detection conductor 24 on the substrate 22 necessary for detecting the throttle opening. That is, in this type of inductive rotation angle sensor, excitation conductors are formed on a substrate so as to correspond to a rotational region of a rotating body to be detected, in other words, an angular region in which the excitation conductors are displaced as the rotating body rotates. And if a signal detection conductor is formed, a desired current excitation action is generated and the rotation angle can be detected.
For example, if the rotation angle of the rotating body is 270°, there is no problem if the excitation conductor and signal detection conductor are formed in an area of about 300° on the substrate with some margin. In the past, it was relatively careless, and there were cases where an excessively wide area was set.

When the above requirements are applied to the throttle sensor 20 of the present embodiment, the opening/closing angle range of the butterfly throttle valve 8 is about 90° at maximum, which is not so wide. For this reason, the excitation conductor 23 and the excitation conductor 23 are arranged in a 120° area on the substrate 22 centered on the throttle shaft 6, corresponding to the angular area in which the position of the excitation conductor 21 is displaced with the rotation of the throttle shaft 6, and with some margin. If the signal detection conductor 24 is formed, there is no problem with the detection function.

5, an excitation conductor 23 is arranged in a fan shape of 120° on the substrate 22 on the side of the axis L1 of the throttle shaft 6 opposite to the intermediate gear 17, that is, in the area on the opposite side of the intermediate gear 17. and signal detection conductors 24 are formed. Of course, a region in which the position of the excitation conductor 21 on the driven gear 14 is changed is also set corresponding to this forming region. In such a case, since the excitation conductor 23 and the signal detection conductor 24 do not exist in the area on the intermediate gear 17 side of the axis L1, the substrate 22 is inevitably unnecessary in this area.

Therefore, this area is formed as a first escape portion 25 by cutting out the substrate 22, and the throttle shaft 6 is disposed closer to the axis line L2 of the intermediate gear 17. As shown in FIG. As a result, even if the substrate 22 and the input gear 17a of the intermediate gear 17 overlap each other in the throttle axial direction, the formation regions of the excitation conductor 23 and the signal detection conductor 24 that perform the desired functions are left on the substrate 22. Even if there is a relationship, it is possible to avoid interference on both sides.

Based on the above knowledge, after arranging the substrate 22 and the input gear 17a of the intermediate gear 17 in a mutually overlapping positional relationship in the throttle axis direction, the excitation conductor 23 and the signal detection conductor 24 are arranged to avoid interference between the two. The present invention takes measures for the formation region and the shape of the substrate 22 . Hereinafter, for convenience of explanation, the surface of the driven gear 14 on which the excitation conductor 21 is formed and the surface of the substrate 22 on which the excitation conductor 23 and the signal detection conductor 24 are formed are referred to as conductor forming surfaces, respectively. 6, the positional relationship of each member will be described in more detail.

As shown in FIG. 6, an output gear 17b is provided adjacent to the input gear 17a of the intermediate gear 17 on the valve body 3 side, and the driven gear 14 meshes with the output gear 17b. The conductor forming surface of the driven gear 14 is close to the input gear 17a of the intermediate gear 17 with a small gap for contact prevention.
Further, the plate thickness of the substrate 22 is thinner than the tooth width of the input gear 17a, and since the substrate 22 is located within the tooth width of the input gear 17a, the substrate 22 and the input gear 17a overlap each other in the throttle axial direction. In this positional relationship, a predetermined minute gap is formed between the excitation conductor 23 and the signal detection conductor 24 on the substrate 22 side and the excitation conductor 21 on the driven gear 14 side.

That is, the position of the driven gear 14 is determined so as to form a slight gap with respect to the input gear 17a of the intermediate gear 17 in the throttle axis direction, and a predetermined minute gap is formed with respect to the conductor forming surface of the driven gear 14. The substrate 22 is positioned to form. As a result, the intermediate gear 17, the driven gear 14, and the substrate 22 are disposed without forming any wasted space in the throttle axial direction, and the substrate 22 overlaps the input gear 17a in the throttle axial direction. is placed in As a result, it is not necessary to raise the rotor 103 from the driven gear 14 by the support stand 105 as in the technique of Patent Document 1, so the outer dimension of the throttle device 1 in the throttle axial direction can be reduced.

Especially in this embodiment, the excitation conductor 21 is provided directly on the driven gear 14 . If the excitation conductor 21 is provided on a rotor that is separate from the driven gear 14, the outer dimension of the throttle device 1 in the throttle axial direction increases at least by the thickness of the rotor. By omitting the rotor, a further reduction in the external dimensions of the throttle device 1 in the direction of the throttle axis can be achieved.

On the other hand, in order to avoid interference due to mutual overlap between the substrate 22 and the input gear 17a of the intermediate gear 17, the excitation conductor 23 and the signal detection conductor 24 on the substrate 22 are separated from each other by the excitation conductor 21 as described with reference to FIG. is formed to form a fan shape of 120° centered on the axis L1 of the throttle shaft 6, corresponding to the angular region in which the position is displaced. These formation regions will be described in more detail.

In this embodiment, as indicated by broken lines in FIG. 5, the excitation conductors 23 and the signal detection conductors 24 are fan-shaped in an area of 60 degrees in both directions across the axis L1 of the throttle shaft 6 in the direction of intake air flow, totaling 120 degrees. is formed to form As a result, the excitation conductor 23 and the signal detection conductor 24 are all located on the side opposite to the intermediate gear 17 from the axis L1 of the throttle shaft 6, in other words, on the side opposite to the drive gear 16 with respect to the intermediate gear 17. positioned. After leaving the excitation conductor 23 and the signal detection conductor 24 on the substrate 22, the substrate 22 is notched in an arc shape corresponding to the outer periphery of the input gear 17a of the intermediate gear 17, so that the first escape portion 25 is formed. formed.

For example, as indicated by the chain double-dashed line in FIG. 5, when the formation area of the excitation conductors 23 and the signal detection conductors 24 is set to 360°, the board 22 interferes with the intermediate gear 17 . For this reason, it becomes necessary to change the position of the throttle shaft 6 together with the substrate 22 in the direction away from the axis L2 of the intermediate gear 17 by, for example, a distance L, which increases the outer dimension of the throttle device 1 in the direction of the gear train. .

On the other hand, according to the present embodiment, the formation of the first relief portion 25 in the substrate 22 allows the throttle shaft 6 to approach the axis L2 of the intermediate gear 17 by the distance L, and The outer dimensions of the throttle device 1 can be reduced.
Of course, the shape of the first relief portion 25 does not necessarily have to be formed in an arc shape, and can be arbitrarily changed as long as it avoids the outer circumference of the input gear 17a.

Electronic components such as a control circuit 26 are also mounted on the substrate 22. For example, the control circuit 26 energizes the excitation conductor 23 and generates a throttle opening signal from the output current of the signal detection conductor 24. Although the overall area of the substrate 22 is smaller than that of a general one, for example, redundant areas are formed on both sides of the axis L1 of the throttle shaft 6 in the direction of flow of intake air. Electronic parts are mounted without any problem.

As described above, according to the present embodiment, the excitation conductor 21, the excitation conductor 23, and the signal detection conductor 24 constituting the throttle sensor 20 are opposed to each other at regular positions to ensure a good throttle opening detection function. Therefore, the outer dimensions can be reduced in both the axial direction of the throttle and the direction of the gear train to achieve miniaturization.

On the other hand, as shown in FIGS. 4 and 5, a total of four power supply terminals 28 and signal An output terminal 29 is provided, and cooperates with a cover 10 attached to the gear housing chamber 4 to constitute a connector 30 shown in FIGS. When the throttle device 1 is assembled to the engine, a connector from the vehicle body side is connected to the connector 30, but it is difficult to connect the connector 30 particularly in a two-wheeled vehicle due to space constraints.

Therefore, in this embodiment, the terminal positions on the board 22 are set so that the connection work of the connector 30 can be easily performed by utilizing the dead space formed due to the peculiar outer shape of the throttle device 1. , the details of which are described below.

As shown in FIGS. 1 and 3, a gear housing chamber 4 is coupled to the valve body 3 to form the overall outline of the throttle device 1, and a motor 15 is mounted on one side of the valve body 3 adjacent to the throttle bore 3a. is furnished. Corresponding to the motor 15, the gear housing chamber 4 extends to one side (downward in the figure) along the direction of the gear train. One side of the valve body 3 and one side of the gear housing chamber 4 both bulge out to one side along the direction of the gear train.

On the other hand, the other end of the valve body 3 is provided with a hose connecting portion 3d (connecting portion) for connection with an air cleaner. It protrudes along one side. 1 and 4, a dead space E is formed between the hose connecting portion 3d and the bulging portion of the gear housing chamber 4 and the motor 15, as indicated by the dashed line in FIGS.

Therefore, in this embodiment, as shown in FIG. , and a power supply terminal 28 and a signal output terminal 29 are provided on the terminal connection portion 31 . Each of the terminals 28 and 29 protrudes along the air flow direction to face the dead space E, and the connector 30 which is inevitably formed in cooperation with the cover 10 also opens facing the dead space.

When connecting the connector 30, an operator grasps the connector on the vehicle body side and brings it closer to the connector 30 on the mating side. Moving. Therefore, the work of connecting the connector 30 can be completed easily and quickly without being hindered by surrounding members.

On the other hand, as indicated by the two-dot chain line in FIG. It is necessary to change the positions of the two female screws 4b on the side of the driven gear 14 among the four corners. Inevitably, it becomes necessary to enlarge the flange 4a, and the throttle device 1 becomes large in the direction of air flow and gear train direction.

On the other hand, in this embodiment, as shown by solid lines in FIG. is formed. Therefore, the side of the substrate 22 opposite to the intermediate gear 17 has a semicircular shape corresponding to the fan-shaped excitation conductor 23 and the signal detection conductor 24, and two female screws 4b are changed in position to avoid interference with the substrate 22. no longer need to. Therefore, there is no need to enlarge the flange 4a, and this factor also greatly contributes to downsizing of the throttle device 1.

Although the description of the embodiment is finished above, the aspect of the present invention is not limited to this embodiment. For example, in the above embodiment, the electronically controlled throttle device 1 for a motorcycle engine having a single throttle bore 3a was embodied, but the present invention is not limited to this. For example, it may be applied to a throttle device for a four-wheeled vehicle, or may be applied to a multiple throttle device having a plurality of throttle bores 3a. In particular, in a multi-throttle system in which each throttle valve 8 is individually driven to open and close by a motor 15, the reduction in outer dimensions described in the embodiment can be obtained by the number of throttle bores 3a, so the effect of downsizing is more pronounced. significantly obtained.

In the above embodiment, the excitation conductor 23 and the signal detection conductor 24 are formed in an area of 60 degrees in both directions across the axis L1 of the throttle shaft 6, for a total of 120 degrees. The angle of the region may be changed from 120°.

For example, as shown in FIG. 7, the excitation conductor 23 and the signal detection conductor 24 may be formed so as to form a 120° sector on either side of the axis L1 of the throttle shaft 6. As shown in FIG. In this case, some regions of the excitation conductor 23 and the signal detection conductor 24 protrude from the axis L1 of the throttle shaft 6 toward the intermediate gear 17, but most of the region protrudes from the axis L1 of the throttle shaft 6 toward the intermediate gear. Located on the 17th side.

Therefore, as in the embodiment, the substrate 22 can be formed with the first relief portion 25 to achieve the same effects, and the present invention includes the formation regions of the excitation conductors 23 and the signal detection conductors 24 as well. In this example, a large surplus area is formed on the other side of the substrate 22 with the axis L1 of the throttle shaft 6 interposed therebetween. be done.

In the above embodiment, the excitation conductor 21 is provided on the driven gear 14 to function as a rotor.

REFERENCE SIGNS LIST 1 electronically controlled throttle device 2 casing 3 valve body 3a throttle bore 3d hose connecting portion (connecting portion)
4 gear housing chamber 6 throttle shaft 8 throttle valve 10 cover 11 bolt (fastening member)
14 driven gear 15 motor 16 drive gear 17 intermediate gear 17a input gear 17b output gear 21 excitation conductor 23 excitation conductor 24 signal detection conductor 22 substrate 25 first relief portion 28 power supply terminal 29 signal output terminal 30 connector 31 terminal connection portion 32 Second Relief E Dead Space

Claims (6)

The rotation of the motor is transmitted from the drive gear to the driven gear via the intermediate gear, and the throttle valve in the throttle bore formed in the valve body of the casing is driven to open and close via the throttle shaft connected to the driven gear, An electronically controlled throttle device for an engine equipped with a throttle sensor comprising a board provided with an excitation conductor and a signal detection conductor so as to face the excitation conductor rotating together with the throttle shaft,
The intermediate gear is composed of a large-diameter input gear that meshes with the drive gear and a small-diameter output gear that meshes with the driven gear, and is a surface on which excitation conductors of the driven gear are formed in the throttle axial direction. The conductor forming surface is close to the input gear of the intermediate gear with a slight gap for contact prevention,
The excitation conductor and the signal detection conductor form a sector centered on the axis of the throttle shaft so as to correspond to an angular region in which the excitation conductor is displaced as the throttle shaft rotates. On the other hand, provided on the substrate so as to be located on the opposite side to the drive gear,
The substrate forms a predetermined minute gap with respect to the conductor forming surface of the driven gear in the throttle axis direction, and is disposed in a positional relationship in which the input gear of the intermediate gear overlaps with the input gear . A first relief portion is formed to avoid interference with
The first relief portion has an arc shape corresponding to the outer circumference of the input gear, leaving the formation regions of the excitation conductor and the signal detection conductor on the substrate. Electronic control throttle device. The excitation conductor and the signal detection conductor are formed in a fan shape in an area of 120 degrees in total, 60 degrees in both directions across the axis of the throttle shaft in the direction of flow of intake air flowing through the throttle bore, and 2. An electronically controlled throttle device for an engine according to claim 1, wherein all regions are located on the side opposite to said intermediate gear with respect to the axis of said throttle shaft. The board is characterized in that surplus regions are formed on both sides of the axis of the throttle shaft in the direction of flow of intake air flowing through the throttle bore, and electronic components of a control circuit for the throttle sensor are mounted in the surplus regions. 3. The electronic control throttle device for an engine according to claim 1 or 2. the valve body has a connection portion provided at an end portion of the throttle bore having a cylindrical shape along the direction of flow of intake air, and the motor is provided adjacent to the throttle bore,
The gear accommodating chamber of the casing accommodates the drive gear, the intermediate gear and the driven gear therein, and extends to one side along a gear train direction perpendicular to the intake air flow direction to accommodate the valve. Form a dead space between the connection part of the body,
The board has a terminal connecting portion extending from the first relief portion to a portion on the connecting portion side of the valve body, and the terminal connecting portion includes a power supply terminal and a 4. An electronically controlled throttle device for an engine according to claim 1 , wherein a signal output terminal is provided to constitute a connector. The gear housing chamber of the casing houses therein the drive gear, the intermediate gear and the driven gear, and has an opening opened to one side with a cover and bolted at four corners. sealed,
5. The substrate according to any one of claims 1 to 4 , characterized in that second escape portions are formed by notching the corners so as to avoid two fastening points on the side of the driven gear. Electronically controlled throttle device for the engine described in . 6. The electronically controlled throttle device for an engine according to claim 1, wherein said excitation conductor is provided directly on said driven gear.

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