JPH0313536Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a throttle valve drive device for an engine, and more specifically, a device for operating a throttle valve that is installed in the intake passage of an engine and adjusts the amount of intake air. The present invention relates to a drive device that employs an accelerator lever.

[Conventional technology]

Conventionally, a throttle valve has been installed in the intake passage of internal combustion engines such as gasoline engines and diesel engines, and the valve opening is changed almost proportionally to the degree of depression of the accelerator pedal. . However, depending on the amount of pedal depression, it may be desirable to have a different opening ratio of the valve. An example is described in which the opening degree of the throttle valve is adjusted by fixing a connecting member and connecting an accelerator wire to the connecting member.

According to such an intake throttle control device, in the low opening range of the throttle valve, the valve opening ratio is small relative to the degree of depression of the accelerator pedal, and in the medium to high opening range, the valve opening ratio is the opposite. The opening ratio increases. Therefore, the effect of the accelerator pedal is adjusted to be less effective in the low speed range.
Especially when starting, where pedal operation is not easy, even if the pedal is pressed a little too much, the engine will not suddenly jump, the engine will stall, or the engine brake will not work excessively. On the other hand, in medium and high speed ranges, the accelerator pedal is more effective and a sharp response can be obtained.

[The problem that the idea aims to solve]

By the way, when the accelerator wire is connected to the cam-shaped connecting member as described above, the rotation radius changes each time the accelerator is operated, which causes the wire to vibrate violently. The opening state of the tuttle valve may be disturbed. Therefore, it is necessary to suppress the vibration of the wire, and a fixed pulley or the like is provided at a position close to the wire attachment part of the non-fan-shaped cam.

However, since the accelerator wire is forced to bend, the degree of fatigue of the wire due to bending increases. In addition, component force loss occurs in the tensile force acting on the wire at the bend, requiring more tensile force than necessary to operate the wire, and this increases wire fatigue. . Therefore, there is a problem that the life of the wire is shortened, and a solution to this problem is desired.

Further, the cam-shaped connecting member as described above tends to be large in size, and there is a problem that it is difficult to install it in an engine head portion where various parts are attached and there is little space.

This invention was developed in view of the above problem, and its purpose is to reduce the opening ratio of the valve in the low opening range to the degree of depression of the accelerator pedal, and to increase the opening ratio in the medium and high opening range. To provide a throttle valve drive device for an engine, which can be miniaturized so as to be easily installed in a narrow place, and which can significantly reduce fatigue of an accelerator wire.

[Means to solve the problem]

The present invention is applied to a throttle valve drive device for an engine in which a throttle valve disposed in an intake passage is driven by an accelerator wire connected to an accelerator operating member.

Its characteristics are as shown in Figure 1.
A throttle lever 3 that rotates together with the support shaft 2 of the throttle valve 1 and an accelerator lever 8 that rotates by an accelerator wire 12 are provided, and both levers 3 and 8 are made of two different links. member 4,
5, and the two link members 4 and 5 have different arm ratios, which are the ratios of the distances from the connection points of the throttle lever 3 and the accelerator lever 8 to the respective support shafts 2 and 9. It is set as follows. A locking portion of one of the levers 3 and 8 is formed in a long hole 11, and when the throttle valve 1 is opened at a low degree, the link member 5 with the smaller arm ratio is brought into contact with the end of the long hole 11. When the throttle valve 1 is opened at a medium or high opening, the link member 4 with the larger arm ratio
Accordingly, the throttle lever 3 is driven.

[Effect of idea]

According to the present invention, when the throttle valve is opened at a low degree, the throttle lever is driven by bringing the link member with the smaller arm ratio into contact with the end of the elongated hole. In the speed range, the effect of the so-called accelerator pedal can become dull. Furthermore, in medium and high speed ranges, the link member with the larger arm ratio drives the throttle lever, making it possible to improve the effectiveness of the accelerator pedal. Furthermore, the lever mechanism can be made smaller than a cam-shaped coupling member, etc., making the device more compact and easier to install in a narrow engine head.

〔Example〕

The present invention will be described in detail below based on examples thereof.

Fig. 1 is a schematic diagram for explaining the configuration and operation of the present invention, in which a throttle lever 3 is fixed to a support shaft 2 of a circular throttle valve 1 that is rotatable in a plane parallel to the paper. There is. This throttle lever 3
Two link members 4 and 5 having different rotation radii R1 and r1 (R1 is shorter than r1) are located at positions sandwiching the support shaft 2, one end of which is 4a and 5a.
It is pivotally mounted for free rotation.

In the vicinity of the throttle lever 3, there is an accelerator lever 8 which is rotatable about a support shaft 9 in the same plane.
is provided, and different radii R2 and r2 (R2 is r
A short hole 10 and a long hole 11 are respectively drilled in the tangential direction of each point on the two circumferences (longer than 2) as base points.

The other end 4b of the link member 4 having an arm ratio R2/R1 that is larger than the arm ratio r2/r1 is placed in the short hole 10, and the other end 4b of the link member 4 has the arm ratio R2/R1 that is smaller than the arm ratio r2/r1 in the long hole 11. other end 5b
are slidably fitted into each other. That is, the two link members 4 and 5 are set to have different arm ratios, which are the ratios of the distances from the connection points of the throttle lever 3 and the accelerator lever 8 to the respective support shafts 2 and 9. It is.

Note that when the throttle valve 1 is in the closed state shown by the solid line, the other ends 4b of the link members 4, 5,
5b is. As shown in the figure, they are located at the right end of each of the short hole 10 and the long hole 11, and as will be described later, when the throttle valve 1 is opened at a low opening, the arm is located at the right end, which is one end of the long hole 11. The other end 5b of the link member 5 with a small ratio comes into contact and drives the throttle lever 3, and when the opening is medium to high, the other end 4b of the link member 4 comes into contact with the left end of the short hole 10 and drives the throttle lever 3. It is designed to be driven.

The accelerator lever 8 has an accelerator wire 1
A sector-shaped circumferential groove 16 is formed to allow the
An accelerator wire 12 is connected to one end of the accelerator wire 12, and can be pulled in the direction of an arrow 13 by operating an accelerator pedal 19, which is an accelerator operating member. An example of the main dimensional ratios applied to this schematic diagram is r2/r1=13/
20, R2/R1=14.5/13, r2=R1.

An example of this device is shown in Figures 2a and b. A circular throttle valve 1 is connected to an intake pipe 1 that introduces intake air in the direction of arrow 20 from an air cleaner (not shown).
5, when the passage 15a is completely closed at an angle of about 10 degrees to a plane perpendicular to this, and when the passage 15a is rotated 80 degrees from that state and becomes parallel to the center line of the intake pipe 15, the passage 15a 15a is in the most open state.

One end of the support shaft 2 for pivotally mounting the throttle valve 1 in the intake pipe 15 projects outside the intake pipe 15.
A throttle lever 3 is fixed to it, and one end 4a of link members 4, 5 is connected to the link member 4, 5 through a ball joint at two points with different rotation radii at both ends.
5a is rotatably locked. A substantially circular accelerator lever 8 is arranged so as to be close to the throttle lever 3 and to be rotatable in the same plane as the throttle lever 3.
will be provided.

A short hole 10 and a long hole 11 are formed in the tangential direction of the accelerator lever 8 at different radial positions across the support shaft 9, respectively. As described above, the other ends 4b and 5b of the link members 4 and 5 are bent and slidably fitted into the short hole 10 and the long hole 11, respectively.

The operation of the above configuration example will be explained below. By operating the accelerator pedal 19 shown in FIG. 1, the accelerator wire 12 is pulled in the direction of arrow 13, and the accelerator lever 14 is
Rotate in direction 4. At the same time, the other end 5b of the link member 5, which is locked to the right end of the elongated hole 11, is similarly rotated in the direction of the arrow 14 while remaining locked. Therefore, the throttle lever 3 is rotated in the direction of the arrow 17 by the link member 5 moving to the left, and the throttle valve 1 is gradually opened.

On the other hand, one end 4a of the link member 4 is moved rightward by the rotation of the throttle lever 3, but since the rotation radius R1 of the one end 4a is smaller than the rotation radius r1 of the one end 5a, the link member 5 is moved leftward. The displacement is smaller than the displacement to the right. Further, since the rotation radius R2 of the short hole 10 is slightly larger than the rotation radius r2 of the long hole 11, the displacement of the short hole 10 to the right is slightly larger than the displacement of the long hole 11 to the left. Therefore, the rightward displacement rate of the link member 4 is slightly smaller than that of the rightward displacement of the short hole 10. Therefore, the other end 4b of the link member 4 separates from the right end of the short hole 10 and relatively slides in the short hole 10 toward the left little by little by the above-mentioned displacement difference.

When the link member 4 rotates to a certain extent, the other end 4b of the link member 4
comes into contact with the left end of the short hole 10. As described above, the rotation radius R2 of the short hole 10 is larger than the rotation radius r2 of the long hole 11, so that the rightward displacement rate of the link member 4 due to rotation of the accelerator lever 8 is greater than that of the link member 5. big. Therefore, the link member 4 now rotates the throttle lever 3 in the same direction.

As mentioned above, since the rotation radius r1 of the one end 5a of the link member 5 in the throttle lever 3 is larger than the rotation radius R1 of the one end 4a of the link member 4, the link member 5 can move the link member 4 to the right. The displacement is greater than the displacement rate to the left. Also,
The rotation radius r2 of the long hole 11 is the rotation radius R of the short hole 10.
2, the displacement to the left is the short hole 10.
smaller than that of Therefore, the locked state of the right end of the elongated hole 11 is released, and the other end 5b of the link member 5 gradually slides inside the elongated hole 11 to the left.

The circular throttle valve 1 described above has a third
As shown in figures a and b, the intake pipe passage 15
The opening area of the intake pipe passage 15a is calculated by subtracting the projected area of the throttle valve 1 in the pipe axis direction from the vertical cross-sectional area S of the intake pipe passage 15a. Subtracted value (B1+
B2) only. Therefore, the intake pipe passage 15a
The opening ratio is (B1+B2/S)×100 [%].

By the way, if the throttle lever 3 is rotated by an accelerator lever via two link members with the same arm ratio, the opening ratio of the intake passage to the rotation angle of the accelerator lever 8 will be at one point in FIG. It changes like a curve A with less bending shown by a chain line. However, in this embodiment, since two link members 4 and 5 with different arm ratios are used, the throttle lever 1 rotated through them causes the opening ratio of the intake passage to be significantly bent midway. It changes like a curved curve B.

In other words, from the initial state of accelerator lever 8, 20
When rotating the throttle lever 3 up to the accelerator lever 8, the other end 5b of the link member 5 abuts and locks the right end of the elongated hole 11.
It is rotated at a rotation ratio of approximately r2/r1, which is slightly slower than the amount of rotation. In the rotation operation from 20 to 80 degrees, the other end 4b of the link member 4 contacts and locks the left end of the short hole 10, so that the throttle lever 3 is rotated somewhat rapidly at approximately R2/R1. It can be rotated by the ratio.

Note that the short hole 10 provided in the accelerator lever 8
Even if the elongated hole 11 is provided in the throttle lever 3 contrary to the illustration, the same operation and effect as described above can be obtained. Of course, each arm ratio r
2/r1 and R2/R1 are not limited to those mentioned above, and by changing their values, the degree of opening ratio of the throttle valve and the boundary position thereof can be changed.

As can be seen from the above explanation, the throttle lever and the accelerator lever are connected by two link members with different arm ratios, which are the ratios of the distances from their respective connection points to their respective support shafts, and one of the two levers is A locking part is formed in the elongated hole, and when the throttle valve is opened at a low opening degree, the throttle lever is driven by bringing the link member with the smaller arm ratio into contact with the end of the elongated hole. Therefore, in the low speed range, the effect of the accelerator pedal is slow, but in the medium and high speed range, the throttle lever is driven by the link member with a larger arm ratio, making it possible to improve the effect of the accelerator pedal. .

Furthermore, since the accelerator wire is guided through the circular circumferential groove of the accelerator lever to drive the accelerator lever, the tension direction of the wire is constant, and tension loss and excessive tension application can be avoided. Furthermore, the restriction of the position of the wire by a pulley or the like and bending fatigue therein are avoided, and the life of the accelerator wire can be extended, which is an extremely practical effect. Further, compared to a cam-shaped connecting member, the lever mechanism can be made smaller, the device can be made more compact, and it can be easily installed in a narrow engine head.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram illustrating the operation of the throttle valve drive device for an engine according to the present invention, Fig. 2 a is a front view of an embodiment to which the present invention is applied, and Fig. 2 b is a plan view of Fig. 2 a. 3A and 3B are longitudinal and cross-sectional views of the throttle valve disposed in the intake pipe, and FIG. 4 is a graph showing the ratio of the opening degree of the intake passage to the rotation angle of the accelerator lever. 1... Throttle valve, 2... Support shaft, 3...
Throttle lever, 4... Link member with larger arm ratio, 5... Link member with smaller arm ratio, 8... Accelerator lever, 9... Support shaft, 10
... Short hole, 11 ... Long hole, 12 ... Accelerator wire, 15a ... Intake passage, 19 ... Accelerator operation member (accelerator pedal).

Claims (1)

[Scope of Claim for Utility Model Registration] In a throttle valve drive device for an engine in which a throttle valve interposed in an intake passage is driven by an accelerator wire connected to an accelerator operating member, A throttle lever that rotates together and an accelerator lever that rotates by an accelerator wire are provided, and both levers are connected by two different link members, and the two link members are connected to the throttle lever. The arm ratio, which is the ratio of the distance from the connection point of each of the throttle lever and the accelerator lever to each support shaft, is set to be different, and the locking part of one of the two levers is formed in a long hole, and the slot When the throttle valve is opened at a low opening, the link member with the smaller arm ratio is brought into contact with the end of the elongated hole, and when the throttle valve is at a medium or high opening, the link member with the larger arm ratio is brought into contact with the end of the elongated hole. A driving device for a throttle valve of an engine, characterized in that it drives a throttle lever.