JP2005090471A - Intake control device for engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an intake control device having a reduced manufacturing cost and improved developing efficiency by simplifying an interlocking mechanism for interlocking sub-throttle valves with main throttle valves. <P>SOLUTION: At the end of a sub-throttle shaft 12 which is driven by an electric motor M and which has the sub-throttle valves 13a, 13b, a cam lever 15 is detachably arranged which has a cam face 15a. A driven lever 6 is arranged at the end of a main throttle shaft 3 which is driven by a driver and which has the main throttle valves 4a, 4b, and a roller 6e of the driven lever 6 is arranged facing the cam face 15a of the cam lever 15. When the sub-throttle valves 13a, 13b are fully opened, the driven lever 6 is rotated via the cam face 15a of the cam lever 15 and the roller 6e to open the main throttle valves 4a, 4b at a first idle opening. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an intake air control device that controls the amount of air directed to an engine, and in particular, an intake air passage that is formed by penetrating through the inside of a throttle body and interlocked with an accelerator grip operated by a driver. The present invention relates to an intake air control device that includes a main throttle valve that opens and closes and a sub-throttle valve that is operated by an electric motor that is driven according to the operating state of the engine and opens and closes an intake passage upstream of the main throttle valve.

A main throttle valve operated by a driver and a sub throttle valve operated by an electric motor are arranged in an intake passage formed in the throttle body, and the electric motor is driven when the main throttle valve is fully closed. The conventional intake control device for an engine that opens the sub-throttle valve and forcibly opens the main throttle valve toward the first idling opening degree regardless of the operation of the accelerator grip by opening the sub-throttle valve (Patent Document) Disclosed in 1).
Referring to FIG. 6 based on Patent Document 1, reference numeral 50 denotes a throttle body having an intake passage 51 formed through the inside thereof. In FIG. 6, the left side of the intake passage 51 is connected to an engine (not shown). The right side of the intake passage 51 is connected to an air cleaner (not shown).
A main throttle shaft 52 is rotatably supported by the throttle body 50 across the intake passage 51, and a main throttle valve 53 that opens and closes the intake passage 51 is attached to the main throttle shaft 52.
A sub-throttle shaft 54 that is rotatably supported by the throttle body 50 across the intake passage 51 is disposed upstream of the main throttle shaft 52 (right side in the figure). A sub-throttle valve 55 that opens and closes is attached.
The intake passage 51 is opened / closed by a main throttle valve 53 and opened / closed by a sub-throttle valve 55 disposed upstream of the main throttle valve 53.
One end 52a of the main throttle shaft 52 protrudes toward one outer side from the throttle body 50, and the throttle drum 56 and the main throttle lever 57 are attached to the one end 52a.
That is, the throttle drum 56, the main throttle lever 57, the main throttle shaft 52, and the main throttle valve 53 rotate synchronously.
A valve opening wire 58 and a valve closing wire 59 connected to an accelerator grip (not shown) are locked to the throttle drum, and the driver operates the accelerator grip to open the valve opening wire 58 and the valve closing valve. The throttle drum 56 rotates forward and backward via the wire 59, whereby the main throttle valve 53 opens and closes the intake passage 51.
When the throttle drum 56 rotates, the main throttle lever 57 also rotates in synchronization with the throttle drum 56.
Further, one end 54a of the sub-throttle shaft 54 also projects outwardly from the throttle body 50, and the sub-throttle lever 60 is attached to this one end 54a.
That is, the sub throttle lever 60, the sub throttle shaft 54, and the sub throttle valve 55 rotate synchronously.
Although not disclosed, the other end of the sub-throttle shaft 54 protrudes from the throttle body 50 toward the outside of the other, and the other end is an electric motor that is driven according to the operating state of the engine. Connected.
That is, the sub-throttle shaft 54 including the sub-throttle valve 55 and the sub-throttle lever 60 is rotated by the electric motor.
As described above, the throttle drum 56, the main throttle lever 57, and the sub-throttle lever 60 are arranged on one side of the throttle body 50 in the same direction.
Reference numeral 61 denotes a link lever rotatably supported on a link lever shaft 62 standing on the throttle body 56. In the drawing, a cylindrical roller 61b is rotatably disposed on a support pin 61c on the left arm portion 61a. Is done.
The link lever 61 is provided with a clockwise rotational force by the link lever spring 63. One end of the link lever spring 63 made of a coil spring is locked to the throttle body 56 side, and the other end is the link lever 61. It is locked to.
The sub throttle lever 60 and the link lever 61 are connected via a link arm 64, and the upper end of the link arm 64 is rotatably supported by a first link pin 64a erected on the sub throttle lever 60. The lower end of the link arm 64 is rotatably supported by a second link pin 64b erected on the link lever 61.
A main operation lever shaft 65 is erected on a wire stay 66 that supports the opening and closing wires 58 and 59. A main operation lever 67 is rotatably supported on the main operation lever shaft 65.
A first arm 67 a is bent and formed at an upper right side of the main operation lever 67, and the first arm 67 a is disposed facing the roller 61 b of the link lever 61.
Further, a second arm 67b is formed to be bent obliquely to the left of the main operation lever 67, and a screw 68 is screwed to the second arm 67b. A tip 68a of the screw 68 is connected to the main throttle. The lever 57 is disposed so as to face the end surface 57a in the rotation direction.
Reference numeral 69 denotes a main operation lever spring comprising a coil spring that applies a counterclockwise rotational force to the main operation lever 67 in the drawing, one end of which is locked to the wire stay 66 and the other end to the main operation lever 67. Locked.
Reference numeral 70 denotes a stop screw for adjusting the minimum opening of the main throttle valve 53. The stop screw 70 is screwed to the wire stay 66, and its tip 70a is in contact with the end surface 57a of the main throttle lever 57. Be placed.

According to such a conventional engine intake control device, when the engine is stopped, the sub-throttle valve 55 is in the fully closed state, and the main throttle valve 53 is also in the fully closed state. Is determined by the state in which the tip 70 a of the stop screw 70 is in contact with the end surface 57 a of the main throttle lever 57.
On the other hand, the roller 61 b of the link lever 61 is disposed at a position where it does not contact the first arm 67 a of the main operation lever 67, and the tip 68 a of the screw 68 screwed to the main operation lever 67 is also the end surface of the main throttle lever 57. It arrange | positions in the position which does not contact | abut to 57a.
Such a state is shown in FIG.

Next, when the engine is cold-started, the sub-throttle shaft 54 rotates counterclockwise when an electric motor (not shown) is driven to rotate, whereby the sub-throttle valve 55 opens the intake passage 51.
When the sub-throttle shaft 54 is rotated in the counterclockwise direction, the sub-throttle lever 60 is rotated in the counterclockwise direction. This rotation is transmitted to the link lever 61 via the link arm 64, and the link lever 61 is counterclockwise. Rotate to
When the link lever 61 is rotated in the counterclockwise direction, the roller 61b comes into contact with the first arm 67a of the main operation lever 67 and presses the first arm 67a downward. The lever 67 rotates clockwise.
According to the clockwise rotation of the main operation lever 67, the tip 68a of the screw 68 comes into contact with the end surface 57a of the main throttle lever 57, and then the main throttle lever 57 is rotated counterclockwise. As the shaft 52 rotates counterclockwise, the main throttle valve 56 is opened from the fully closed state to a desired first idling opening degree.
That is, when the engine is cold-started, the main throttle valve 53 is opened via the sub throttle lever 60, the link arm 64, the link lever 61, the main operation lever 67, and the main throttle lever 57 by opening the sub throttle valve 55. The desired first idling opening can be opened.

When the warm-up operation is completed after the engine is started and the engine is warmed, the sub-throttle valve 55 is rotated clockwise again by the electric motor and rotationally displaced to close the intake passage 51. According to this, the sub-throttle lever 60 and the link lever 61 rotate clockwise, the contact between the roller 61b and the first arm 67a of the main operation lever 67 is released, and the main operation lever 67 in the free state is It rotates counterclockwise by the spring force of the spring 69.
According to the counterclockwise rotation of the main operation lever 67, the contact of the tip 68a of the screw 68 with the end surface 57a of the main throttle lever 57 is released, so that the main throttle lever 57 is a spring of a main throttle return spring (not shown). The clockwise rotation of the main throttle lever 57 is stopped by rotation of the main throttle lever 57 while the end surface 57a of the main throttle lever 57 is in contact with the tip 70a of the stop screw 70. Is retained.
JP 2002-129987 A

Such a conventional engine intake control device has the following problems.
The link arm 64 is rotatably supported by the first link pin 64a and is rotatably supported by the second link pin 64b. The link lever 61 is rotatably supported by the link lever shaft 62. Further, the main operation lever 67 is The main operation lever shaft 65 is rotatably supported.
As described above, according to having a large number of rotating parts supported by the shaft, in order to stably maintain the rotation of such rotating parts over a long period of time, the material of the shaft and the bearing hole in the rotating part, surface treatment However, the improvement of development efficiency cannot be expected because it requires a lot of development man-hours such as selective adaptation of surface hardness, etc., or arrangement of bearing collars with respect to the rotating part.
In particular, when adopting the above-described structure in a two-wheeled vehicle, the rotating part is directly exposed to the outside air, so that foreign matter easily enters and adheres to the rotating part. Or various vibrations act on a rotating part. Therefore, the above problem is particularly great.
In order to transmit the rotation of the sub throttle valve 55 to the main throttle valve 53, the sub throttle lever 60, the first link pin 64a, the link arm 64, the second link pin 64b, the link lever 61, the link lever shaft 62, the link The lever spring 63, the support pin 61c, the roller 61b, the main operation lever 67, the main operation lever shaft 65, the main operation lever spring 67, the screw 68, and the main throttle lever 57 require a large number of parts and their assembly is complicated. However, the increase in the number of parts and the increase in assembly man-hours cannot achieve a reduction in manufacturing cost.
In addition, it is not preferable that the assembly is complicated and the assembly man-hour is increased because the maintainability deteriorates.
Further, when many parts are arranged on one side surface of the throttle body 50, the appearance of the throttle body 50 becomes complicated, and the appearance of the throttle body 50 that is directly exposed to the outside air like a two-wheeled vehicle is clearly organized. I can't.
Further, the setting of the first idle opening degree of the main throttle valve 53 for the opening operation of the sub throttle valve 55 is appropriately set according to the type of engine, the destination, the use condition, the use environment, and the like. In this case, it is necessary to change the link arm 64, the link lever 61, or the main operation lever 67, and this change requires a great deal of cost.

  The intake control device for an engine according to the present invention has been made in view of such problems, and its production cost is achieved by interlocking the sub-throttle valve and the main throttle valve with an interlock device having a small number of parts and a small number of assembly steps. It is possible to provide an intake control device for an engine in which the first idle opening degree of the main throttle valve corresponding to the opening operation of the sub throttle valve can be easily set and the degree of freedom in selecting the first idle opening degree is high. Objective.

Means to achieve the task

In order to achieve the above object, the intake control device for an engine according to the present invention has an intake passage penetrating through the throttle body and is linked to an accelerator grip operated by a driver in the intake passage. A main throttle valve for opening and closing the intake passage,
In the engine intake control device, which is disposed in the intake passage upstream of the main throttle valve and includes a sub-throttle valve that is operated by an electric motor that is driven according to the operating state of the engine to open and close the intake passage.
A cam lever with a cam surface is attached to the end of the sub-throttle shaft that is rotatably supported by the throttle body and the sub-throttle valve is attached, and is also rotatably supported by the throttle body and the main throttle valve is attached. A driven lever facing the cam surface is attached to the end of the attached main throttle shaft, and when the main throttle valve is fully closed, the driven lever is placed close to the cam surface of the cam lever, and the sub-throttle valve is fully opened. The first feature is that the main throttle valve is opened toward the first idle opening degree via the driven lever in accordance with the rotation of the cam lever at the time of turning to.

According to the first feature, the rotation in the opening direction of the sub-throttle valve is transmitted to the driven lever via the cam surface of the cam lever, and the first idle opening of the main throttle valve is set by the rotation of the driven lever by the cam surface. The
Therefore, the linkage between the sub throttle valve and the main throttle valve is achieved by the cam lever and the driven lever having the cam surface, so that the number of parts and the number of assembling steps can be reduced.
In the interlocking operation of the sub throttle valve and the main throttle valve, the sliding part is only the cam surface of the cam lever and the driven lever that contacts the cam surface. Does not require a lot of development man-hours.
Also, the setting of the first idling opening degree of the main throttle valve can be freely and easily changed by changing the cam surface shape of the cam lever with respect to the displacement of the sub throttle valve toward the opening direction.

In addition to the first feature, the intake control device for an engine according to the present invention is urged in a fully closed direction of the main throttle valve by a main throttle return spring,
A second feature is that the main throttle return spring is formed by a coil spring and is disposed on the outer periphery of the main throttle shaft in the vicinity of the driven lever.

According to the second feature, the driven lever is pressed against the cam surface of the cam lever by the spring force of the main throttle return spring. When the sub-throttle valve is opened, the cam surface of the cam lever rotates the driven lever toward the open side of the main throttle valve against the spring force of the main throttle return spring, which sets the first idling opening of the main throttle valve Is done.
When the cam lever rotates when the sub-throttle valve is opened, the contact point between the cam surface of the cam lever and the driven lever and the point of action of the spring force of the main throttle return spring against the driven lever are arranged close to each other in the longitudinal direction of the main throttle shaft. Therefore, the driven lever can be smoothly rotated by rotating the cam lever.

  Furthermore, in addition to the first feature, the engine intake control device according to the present invention has a third feature that the cam lever is detachably disposed at the end portion of the sub-throttle shaft by a nut.

  According to the third feature, the cam lever can be removed from the sub-throttle shaft very easily by removing the nut from the sub-throttle shaft when changing the shape of the cam surface or during maintenance of the cam lever.

The invention's effect

According to the first feature of the present invention, since the sub-throttle valve and the main throttle valve are linked by the cam lever and the driven lever, the number of parts and assembly man-hours can be greatly reduced, and the manufacturing cost of the intake control device can be reduced. . Further, the setting of the first idling opening degree of the main throttle valve can be changed very easily by changing the cam surface shape of the cam lever, so that a highly versatile intake control device can be provided.
In addition, according to the above, since the cam part and the driven lever are provided as the sliding part, the material of the sliding part, the surface treatment, etc. can be easily set, and the man-hour for the durability test can be reduced. Development man-hours can be greatly reduced.
Also, when mounted on a two-wheeled vehicle, there is only one sliding part, so the degree of foreign matter entering or attaching to the sliding part is reduced, and stable intake control can be performed over a long period of time. it can.
Furthermore, there are few parts arranged on the side surface of the throttle body, the appearance can be refreshed, and it is particularly preferable in the case where it is exposed to the outside air such as a motorcycle.

  Further, according to the second feature of the present invention, the contact point where the cam surface of the cam lever contacts the driven lever and the operating point of the main throttle return spring with respect to the driven lever can be arranged in the vicinity of the driven lever. The driven lever can be smoothly rotated with respect to the movement, and does not become a great resistance against the rotation of the electric motor.

  Furthermore, according to the third feature of the present invention, it is possible to very easily perform maintenance work for replacing the lever or cleaning the cam surface in accordance with the change in the specification of the cam surface.

An embodiment of an intake control apparatus for an engine according to the present invention will be described below with reference to FIGS.
FIG. 1 is a front view seen from the main throttle valve side. FIG. 2 is a right side view of FIG.
3 is a left side view of FIG. 4 is a longitudinal sectional view of a main part taken along line AA in FIG.
5 is a longitudinal sectional view taken along line BB in FIG. It is.

The throttle body 1 has two intake passages 2a and 2b extending therethrough, and in FIG. 5, the left side of the intake passage 2a is connected to the engine via an intake pipe, and the right side of the intake passage 2a is an air cleaner. Connected to. (Engine, intake pipe and air cleaner are not shown)
Reference numeral 3 denotes a main throttle shuttle that traverses the intake passages 2a and 2b and whose center and both ends are rotatably supported by the throttle body 1, and is a butterfly-type main throttle valve disposed in each intake passage 2a and 2b. 4a and 4b are attached to the main throttle shaft by screwing.
That is, as the main throttle shaft 3 rotates, the main throttle valves 4a and 4b open and close the intake passages 2a and 2b facing the synchronously.
Reference numeral 5 denotes a main throttle shaft angle sensor for detecting the rotation angle of the main throttle shaft 3, which is fitted in the left end 3a of the main throttle shaft 3 protruding leftward from the left side wall of the throttle body 1 in FIG. Be placed.
On the other hand, a driven lever 6 and a main throttle drum 7 are arranged at the right end 3b of the main throttle shaft 3 protruding rightward from the left side wall 1a of the throttle body 1 in FIG. 3 is attached so as to rotate in synchronism with the main throttle shaft 3 by a nut 8 screwed to the right end 3b.
More specifically, the cross section of the right end 3b of the main throttle shaft 3 is formed in a D-cut shape, and is drilled through the mounting hole 6a penetrating through the driven lever 6 and the main throttle drum 7. The mounting hole 7a is formed in a D-cut shape, and the mounting hole 6a of the driven lever 6 and the mounting hole 7a of the main throttle drum 7 are inserted into the D-cut right end 3b of the main throttle shaft 3, and then the nut 8 is inserted into the main By screwing to the right end 3b of the throttle shaft 3, the driven lever 6 and the main throttle drum 7 can be attached and the driven lever 6 and the main throttle drum 7 can be attached. The main throttle shaft 3 can be rotated synchronously.
9 is a main throttle return spring comprising a coil spring disposed between the right side wall 1a in FIG. 4 of the throttle body 1 and the driven lever 6 and wound around the outer periphery of the main throttle shaft 3. One end of the main throttle return spring 9 is locked to the throttle body 1, and the other end is locked to a first arm 6 b that is bent from the driven lever 6.
According to the above, the main throttle shaft 3 including the driven lever 6 and the main throttle drum 7 is given a clockwise spring force in FIG. 2, in other words, a closing spring force to the main throttle valves 4a and 4b.
Further, the driven lever 6 is formed with a second arm 6c bent toward the right side wall 1a side of the throttle body 1, and the lower end surface 6ca of the second arm 6c is screwed to the throttle body 1. The front end 10a of the main throttle valve stop screw 10 is disposed in contact with it. This is disclosed in FIGS.
When the main throttle valve stop screw 10 is moved forward and backward, the driven lever 6 has a tip 10a of the main throttle valve stop screw 10 that abuts the lower end surface 6ca of the second arm 6c of the driven lever 6. Rotate in direction or counterclockwise.
Therefore, by adjusting the main throttle valve stop screw 10 by screwing, the fully closed degree of the main throttle valves 2a and 2b, in other words, the minimum opening degree can be adjusted.
The main throttle drum 7 will be described again with reference to FIG. 2. The main throttle drum 7 is provided with a first locking hole 7b and a second locking hole 7c with a gap in the circumferential direction. A wire end 11c of a valve opening wire 11a connected to an accelerator grip (not shown) is inserted into and locked in the first locking hole 7b, and connected to an accelerator grip (not shown) in the second locking hole 7c. The wire end 11d of the closed valve closing wire 11b is inserted and locked.
According to the above, when the accelerator grip is operated and the valve opening wire 11a is pulled, the main throttle drum 7 rotates the main throttle drum 7 counterclockwise in FIG. 2 against the spring force of the main throttle return spring 9. Accordingly, the main throttle valves 4a and 4b mechanically open the intake passages 2a and 2b by the driver.
On the other hand, when the accelerator grip is operated and the valve closing wire 11b is pulled, the main throttle drum 7 receives the spring force of the throttle return spring 9 and rotates the main throttle drum 7 in the clockwise direction in FIG. The throttle valves 4a and 4b mechanically close the intake passages 2a and 2b by the driver.

Reference numeral 12 denotes a sub-throttle shaft disposed on the upstream side of the main throttle shaft 3. Here, the upstream side refers to the flow direction of the air flowing in the intake passages 2a and 2b. In FIG. 3 and on the right side of the main throttle shaft 3 in FIG.
The sub-throttle shaft 12 traverses the intake passages 2a and 2b, and its center and both ends are rotatably supported by the throttle body 1 to open and close the butterfly-type sub-throttle valve 13a and the intake passage 2b that open and close the intake passage 2a. The butterfly-type sub-throttle valve 13b is attached to the sub-throttle shaft 12 by screwing.
That is, as the sub-throttle shaft 12 rotates, the respective sub-throttle valves 13a and 13b open and close the intake passages 2a and 2b facing the synchronously.
The left end 12a of the sub-throttle shaft 12 protrudes further leftward from the left side wall of the throttle body 1, and the left end 12a of the sub-throttle shaft 12 detects the rotation angle of the sub-throttle shaft 12. A sub-throttle shuttle angle sensor 14 is fitted and disposed, and an electric motor M for rotating the sub-throttle shaft 12 is connected.
On the other hand, a cam lever 15 is attached to the right end 12b of the sub-throttle shaft 12 protruding rightward from the right side wall 1a of the throttle body 1.
Specifically, the cross section of the right end 12b of the sub-throttle shaft 12 is formed in a D-cut shape, and the mounting hole 15c that is drilled through the cam lever 15 is formed in a D-cut hole shape.
Then, the cam lever mounting hole 15c is inserted into the right end 12b of the sub-throttle shaft 12, and then the nut 16 is screwed to the right end 12b of the sub-throttle shaft 12, whereby the cam lever 15 is engaged with the sub-throttle shaft 12. The cam lever 15 and the sub-throttle shaft 12 can be rotated synchronously while being attached to the stop portion 12c.
The cam lever 15 has a cam surface 15a formed on the outer peripheral surface thereof. A basic cam profile of the cam surface 15a will be described with reference to FIG.
The cam profile of the cam surface 15a is determined so that the radius r from the center 15b of the cam lever 15 to the cam surface 15a gradually increases as the radius r moves in the clockwise direction.
That is, the radius r2 at the position b moved in the clockwise direction is larger than the radius r1 at the reference position a. The increasing rate of the radius r from the radius r1 to the radius r2 is set as appropriate.
Returning to the description of the driven lever 6 again, the driven lever 6 is formed with a third arm 6d extending toward the cam lever 15, and the cam surface of the cam lever 15 is formed at the tip of the third arm 6d. A roller 6e facing 15a is arranged.
Specifically, the roller 6c has a cylindrical shape and is rotatably supported on a shaft 6f attached to the tip of the third arm 6d.

Next, the operation of the intake control device described above will be described.
When the engine is stopped, the main throttle drum 7 is not subjected to any operating force by the driver, so the spring force of the main throttle return spring 9 receives the clockwise spring force in FIG. The lower end surface 6ca of the two arms 6c is maintained in contact with the tip 10a of the main throttle valve stop screw 10, and thereby the minimum opening of the main throttle valves 4a and 4b is determined.
The minimum opening degree of the main throttle valves 4a and 4b can be changed by screwing the main throttle valve stop screw 10.
On the other hand, the sub-throttle valves 13a and 13b are held in a fully closed state, for example, because the electric motor M as the driving means does not operate.
The positions of the main throttle drum 7 and the cam lever 15 including the driven lever 6 in the above state are shown by solid lines in FIG. 2, and the positions of the main throttle valve 4a and the sub throttle valve 13a are shown by dotted lines in FIG.
When the engine is stopped, there is no problem even if the opening degree of the sub-throttle valves 13a and 13b is maintained at any position.

Next, a description will be given of the cold start when the engine ambient temperature is low.
When starting the engine, when the main switch of the engine is turned on, an ECU (not shown) outputs a drive signal to the electric motor M based on information such as intake air temperature, engine coolant temperature, oil temperature, and the like input thereto. The electric motor M is driven in accordance with the signal to rotate the sub-throttle shaft 12 greatly.
For example, in FIG. 2, the sub-throttle shaft 12 is rotated about 77 degrees counterclockwise, and this rotation causes the sub-throttle valves 13a and 13b to fully open the intake passages 2a and 2b.
As described above, when the sub-throttle shaft 12 is largely rotated counterclockwise, the cam lever 15 is also rotated counterclockwise in synchronism with this. According to the rotation of the cam lever 15 in the counterclockwise direction, The cam surface 15a of the cam lever 15 contacts the roller 6e, and then the driven lever 6 is rotated counterclockwise in FIG. 2 while pressing the roller 6e upward.
According to the above, the main throttle valves 4a and 4b, which have been held at a low opening by the main throttle valve stop screw 10, open the intake passages 2a and 2b in synchronization with the rotation of the driven lever 6 in the counterclockwise direction. Thus, the first idle opening degree of the main throttle valves 4a and 4b can be obtained.
The positions of the cam lever 15 and the roller 6e in the above state are indicated by a one-dot chain line in FIG.
In such a state, when the cell motor operates to start the engine, an increased amount of start air suitable for cold start can be supplied to the engine, so that the engine can be started in the cold state. It can be performed well.

  When the warm-up operation of the engine is completed after the engine is started, the electric motor M rotates the sub-throttle shaft 12 in the clockwise direction in FIG. 2 by a signal from the ECU, whereby the driven lever 6 by the cam surface 15a of the cam lever 15 is rotated. The contact with the roller 6e is released, and the main throttle valves 4a and 4b can be returned to the normal operating state.

As described above, according to the intake control device of the present invention, the interlock of the sub throttle valve and the main throttle valve is driven by the driven lever attached to the main throttle shaft, the cam lever attached to the sub throttle shaft, and the driven Since it is made up of a roller provided on the lever, the number of parts and assembly man-hours can be greatly reduced as compared with the conventional interlocking mechanism, thereby greatly reducing the manufacturing cost of the intake air control device.
In addition, according to the above-mentioned interlocking, the sliding part is only the roller and the cam surface of the cam lever. Therefore, the development man-hour can be reduced with respect to the selection of the materials and the selection of the surface treatment. Therefore, stable intake control can be performed over a long period of time.
Further, since only the driven lever and the cam are present on the side of the throttle body, the appearance of the throttle body can be compactly and neatly arranged. This is particularly preferable in the case where the throttle body is exposed to the outside like a two-wheeled vehicle.

According to the arrangement of the main throttle return spring close to the driven lever, the contact point X between the cam surface of the cam lever and the roller and the locking point Y of the main throttle return spring with respect to the driven lever Since they can be arranged close to each other in the longitudinal direction, the cam lever can be operated smoothly without causing squeezing of the driven lever during the operation of the cam lever. It is effective to work.
The contact point X and the locking point Y are shown in FIG.

  Also, according to the cam lever being detachably attached to the sub-throttle shaft using a nut, it is extremely difficult to change the cam lever when the cam lever cover surface is changed depending on the engine or the destination of the engine. It can be easily performed and maintenance work of the cam lever can be facilitated.

  The intake passage formed in the throttle body may be single, and the driven lever may be formed using a part of the main throttle drum.

The front view which looked at the intake control device which becomes this invention from the main throttle valve side. The right view of FIG. The left view of FIG. The principal part longitudinal cross-sectional view in the AA of FIG. The longitudinal cross-sectional view in the BB line of FIG. The side view of the conventional intake control device.

Explanation of symbols

1 Throttle body 2a, 2b Intake passage 3 Main throttle shaft 4a, 4b Main throttle valve 6 Drive lever 6e Roller 7 Main throttle drum 9 Main throttle return spring 12 Sub throttle shaft 13a, 13b Sub throttle valve 15 Cam lever 15a Cam surface

Claims (3)

A main throttle valve that opens and closes the intake passage in conjunction with an accelerator grip operated by a driver, and an intake passage is formed through the inside of the throttle body.
In the engine intake control device, which is disposed in the intake passage upstream of the main throttle valve and includes a sub-throttle valve that is operated by an electric motor that is driven according to the operating state of the engine to open and close the intake passage.
A cam lever with a cam surface is attached to the end of the sub-throttle shaft that is rotatably supported by the throttle body and the sub-throttle valve is attached, and is also rotatably supported by the throttle body and the main throttle valve is attached. A driven lever facing the cam surface is attached to the end of the attached main throttle shaft, and when the main throttle valve is fully closed, the driven lever is placed close to the cam surface of the cam lever, and the sub-throttle valve is fully opened. An intake control device for an engine, wherein the main throttle valve is opened toward the first idle opening degree via a driven lever in accordance with the rotation of the cam lever at the time of rotation. The main throttle shaft is urged in the fully closed direction of the main throttle valve by a main throttle return spring,
2. The intake control apparatus for an engine according to claim 1, wherein the main throttle return spring is formed by a coil spring and disposed on the outer periphery of the main throttle shaft in the vicinity of the driven lever.   2. The intake control apparatus for an engine according to claim 1, wherein the cam lever is detachably disposed at an end portion of the sub-throttle shaft with a nut.

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