JPS6338530B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a throttle valve idling opening detection device for electrically detecting the throttle valve opening of a carburetor, particularly the idling opening of the throttle valve. This throttle valve idling opening detection device is used, for example, as a means for reducing HC during deceleration in an engine using a carburetor.

In other words, by placing a solenoid valve in the slow fuel system,
A revolution device that detects the engine speed and a throttle valve idling opening detection device that detects the idling opening of the throttle valve are arranged in the electric circuit of this solenoid valve. Each of the devices described above detects the idling opening state of the throttle valve due to high rotational speed and deceleration, and operates the electromagnetic valve to shut off the slow fuel system.

As shown in FIG. 1, such a conventional throttle valve idling opening detection device has a throttle valve 3 arranged in an intake passage 2 passing through a carburetor main body 1, and a throttle valve that rotates synchronously with the throttle valve 3. A throttle valve lever 5 is provided at the end of the valve shaft 4 that projects outside the carburetor body 1, and a throttle valve opening adjustment screw 6 is screwed onto the carburetor body 1 in correspondence with one end 5A of the throttle valve lever 5. A micro switch adjustment screw 7 is screwed onto the other end 5B of the throttle valve lever 5, and a micro switch 8 for opening and closing an electric circuit is arranged in correspondence with the micro switch adjustment screw 7. When the valve lever 5 comes into contact with the throttle valve opening adjusting screw 7 and the throttle valve 3 reaches the idling opening, the micro switch adjusting screw 7 comes into contact with the micro switch 8 and controls the electric circuit to open or close. It is.

According to such a conventional throttle valve idling opening detection device, first the throttle valve opening adjustment screw 6 is screwed to rotate the throttle valve lever 5 to determine the minimum idling opening of the throttle valve 3, and then the micro switch is rotated. The adjustment screw 7 is screwed to adjust the position relative to the micro switch 8, and the throttle valve 3
When the opening reaches the idling position, the microswitch adjustment screw 7 is operated to open or close the microswitch 8.

According to such a conventional throttle valve idling opening detection device, the throttle valve opening adjustment screw 6 is operated to adjust the idling opening, and the microswitch adjustment screw 7 is operated to adjust the operation (contact) of the microswitch 8. , and must be performed separately, and the operations are performed twice, resulting in poor workability for adjustment.

In addition, since the throttle valve opening adjustment screw 6 and the micro switch adjustment screw 7 can be operated in two directions, the degree of freedom in designing the operation direction is hindered, and in particular, various devices are arranged around the engine. This was a problem. Furthermore, since the ends of the throttle valve opening adjusting screw 6 and the micro switch adjusting screw 7 come into contact with the throttle valve lever 5, it is necessary to increase the strength of the throttle valve lever 5.

In view of the above, the present invention has been developed by integrally forming a throttle valve opening adjustment screw that adjusts the opening of the throttle valve and a switch body that opens and closes contacts of an electric circuit, and adjusting the throttle valve opening by operating from a single direction. An object of the present invention is to obtain a throttle valve idling opening detection device for a carburetor which has excellent workability and a high degree of freedom in design of the operating direction.

An embodiment of the present invention will be described below with reference to FIGS. 2 and 3.

A throttle valve 13 is disposed in an intake passage 12 that penetrates the carburetor body 11, and a throttle valve lever 15 is provided at the end of a throttle valve shaft 14 that rotates synchronously with the throttle valve 13 and projects outside the carburetor body 11. Fixed. A throttle valve return spring 16 that applies a rotating force in the closing direction (clockwise in the figure) to the throttle valve 13 is locked to the throttle valve lever 15, and the throttle valve return spring 16 is attached to the throttle valve lever 15 in a manner that corresponds to the bent portion 15A at one end. An idling opening detection device 17 is arranged.

Next, the throttle valve idling opening detection device 17 will be explained.

Reference numeral 18 denotes a housing made of an insulating material such as polyester resin or epoxy resin, with a stepped portion 18A provided therein and a threaded portion 18B penetrating through the upper portion of the housing.A terminal is provided in the stepped portion 18A. 19A,1
9B are arranged respectively, and a cup-shaped switch body 20 made of a conductive material such as copper is brought into contact with the terminals 19A and 19B in correspondence with the terminals.
The switch main body 20 is further provided with a protrusion 22 made of an insulating material such as polyester resin, and the protrusion 2
2 protrudes from the lower part of the casing 18 to the outside of the casing 18, and this protruding end is brought into contact with the bent portion 15A of the throttle valve lever 15.

In addition, 23 connects the switch body 20 to the terminal 19A,
It is a switch pressing spring that urges the switch body 20 to move away from the switch body 19B.
It is compressed between the inner upper surface of the housing 18 and the inner upper chamber surface of the housing 18 .

As shown in FIG. 2, the spring set load of the switch pressing spring 23 in the spring set state is equal to the spring set load of the throttle valve return spring 16 when the throttle valve 13 is idling open.
The spring force is set to be smaller (weaker) than the spring force of.

Then, 24 attaches one end to the carburetor main body 11 with screw 2.
5, and the stay 2
4 has a bifurcated long groove 24 at the other end that prevents rotation of the housing 18 and allows vertical movement in the figure.
A is formed in the upper surface of the stay 24, and a support hole 24B is formed in the middle portion of the upper surface of the stay 24 to rotatably suspend and hold an adjustment screw, which will be described later.

Then, the locking part 18C protruding from the outer circumference of the housing 18 is fitted into the long groove 24A of the stay 24, and the protrusion 22 protruding from the housing 18 corresponds to the bent part 15A of the throttle valve lever 15. and place it.

Reference numeral 26 is an adjustment screw, and a head flange 26A is provided at its upper end, and a gap H is provided in the head flange 26A.
An intermediate locking flange 26B is provided with a male screw portion 26C below the intermediate locking flange 26B.
is provided. The adjustment screw between the head flange 26A and the intermediate locking flange 26B is an intermediate shaft 26D. The housing 18 is suspended and held on the stay 24 by the adjustment screw 26 as follows.

That is, the intermediate shaft portion 26D of the adjustment screw 26 is fitted into the support hole 24B, and the upper surface of the intermediate locking collar portion 26B is arranged to correspond to the lower surface of the stay 24. Head flange 2
6A corresponds to the lower surface, and in this state, the set spring 27 is contracted between the upper surface of the stay 24 and the lower surface of the head flange 26A. Further, a male threaded portion 26C at the lower end of the adjustment screw 26 is screwed into a threaded portion 18B of the housing 18.

Therefore, the housing 18 is suspended and held by the set spring 27 via the adjustment screw 26. 28 is a valve-opening operation wire that applies an operating force to the throttle valve 13 in the opening direction, and 29 is a valve-closing operation wire that applies an operating force to the throttle valve 13 in the closing direction.

Next, its effect will be explained.

The idling opening degree of the throttle valve 13 is set as follows. That is, when the throttle valve 13 is idling open, a clockwise pulling force is applied to the throttle valve lever 15 by the valve-closing operation wire 29. Therefore, the throttle valve lever 15 receives a clockwise rotational force together with the throttle valve return spring 16, and the bent portion 15A of the throttle valve lever 15 receives the throttle valve idling opening detection device 17.
It abuts against the protrusion 22 of.

According to this, the rotational force of the throttle valve lever 15 is transmitted to the switch body 20 via the protrusion 22.
At this time, the spring force of the switch pressing spring 23 that urges the switch body 20 toward the bent portion 15A of the throttle valve lever 15 is set to be weak, as is the spring force of the throttle valve return spring 16, so that the switch body 20 is connected to the terminals 19A, 19B. through the housing 18
is mechanically transmitted to the stepped portion 18A.

Although the casing 18 including the switch body 20 is about to move upward in the figure, the upper surface of the intermediate locking flange 26B of the adjustment screw 26 screwed into the casing 18 is the lower surface of the stay 24. Since the housing 18 is mechanically abutted against the housing 18, the housing 18 does not move upward.

Therefore, the housing 18 including the protrusion 22 and the switch body 20 is fixedly arranged with respect to the stay 24, so that the throttle valve lever 15 can be held at a constant position, and the throttle valve The idling opening degree of No. 13 is determined.

When the throttle valve 13 is idling, the switch pressing spring 23 is deflected by the strong rotational force of the throttle valve return spring 16 and the valve closing operation wire 29, and the switch body 20 is bent to the terminal 19A. , 19B, the electric circuit could be closed.

Further, in order to adjust the idling opening degree of the throttle valve 13, the adjusting screw 26 is rotated. For example, if a right-handed thread is carved into the male threaded portion 26C of the adjustment screw 26 and the adjustment screw 26 is rotated clockwise,
The housing 18 moves upward in the figure in accordance with the rotation of the adjustment screw 26. This is housing 18
Since the locking portion 18C is prevented from rotating by the long groove 24A, the rotation of the adjusting screw 26 increases the gap H between the head flange 26A of the adjusting screw 26 and the intermediate locking flange 26B. The adjustment screw 26 and the housing 18 move upward by this increase.

According to this upward movement of the housing 18, the switch body 20 including the protrusions 22 moves to the step portion 1 of the housing 18.
Since the protrusion 22 moves upward synchronously with the housing 18 while contacting the protrusion 8A, the protrusion 22 moves upward in the figure as a result. Therefore, the throttle valve lever 15 rotates clockwise to reduce the opening degree of the throttle valve 13.

On the other hand, when the adjustment screw 26 is rotated counterclockwise, the housing 18 moves downward in the figure in accordance with the rotation of the adjustment screw 26. According to this, the stepped portion 18A,
The switch body 20 and the protrusion 22 also move downward synchronously, causing the protrusion 22 to rotate the throttle valve lever 15 in the counterclockwise direction, thereby rotating the throttle valve 13 in the opening direction. .

Therefore, by appropriately rotating the adjusting screw 26, a desired idling opening degree of the throttle valve 13 can be obtained. Furthermore, in the idling opening state, the switch body 20 is always in contact with the terminals 19A and 19B as described above, so that the electric circuit can be reliably closed.

When the throttle valve 13 is opened by pulling the operating wire 28 from the throttle valve idling state (it rotates counterclockwise in the figure), the throttle valve lever 15 also rotates counterclockwise at the same time, so that the throttle valve 13 is opened. Protrusion 22 of bent portion 15A of lever 15
The pressure on the person is released.

According to this, the switch body 20 is immediately pressed downward by the switch pressing spring 23, and the switch body 20 is separated from the terminals 19A and 19B, so that the electric circuit can be immediately opened.

As described above, in the carburetor throttle valve idling position detection device according to the present invention, the adjustment of the idling opening of the throttle valve and the operation (contact point) of the electric circuit can be performed simply by turning the adjustment screw, and the adjustment operation Since there is only one, the workability for adjustment can be improved.

Furthermore, since the adjustment operation can be performed by rotating the adjustment screw in one direction, the degree of freedom in designing the operation direction can be increased.
Furthermore, when pulling the valve-closing operating wire to bias the throttle valve in the closing direction, even if the throttle valve has already returned to its idling opening, the traction force may be further applied to the valve-closing operating wire. In such a state, the upper surface of the intermediate locking flange of the adjustment screw that holds the casing in suspension comes into contact with the lower surface of the stay, so even if unnecessary pulling force is applied to the valve-closing operation wire, the idling opening of the throttle valve will not change. A stable idling opening can be obtained without any change.

[Brief explanation of the drawing]

FIG. 1 is a side view showing an embodiment of a conventional throttle valve idling opening detection device for a carburetor, and FIG. 2 is a side view showing an embodiment of a carburetor throttle valve idling opening detection device according to the present invention. side view including a partial sectional view;
FIG. 3 is a perspective view of the stay shown in FIG. 2. 13... Throttle valve, 15... Throttle valve lever, 16
... Throttle valve return spring, 19A, 19B
...Terminal, 20...Switch body, 23...Switch pressing spring, 24...Stay, 24B...
...Support hole, 26...Adjustment screw, 26A...Head flange, 26B...Intermediate locking flange.

Claims (1)

[Claims] 1. Terminals 19A, 1 fixedly disposed on a step 18A provided inside the casing 18 made of an insulating material.
9B; A switch body 20 made of a conductive material and arranged corresponding to the terminals 19A and 19B to open and close both terminals 19A and 19B; A switch body 20 formed integrally with the switch body 20 and synchronously with the throttle valve 13; Rotating throttle valve lever 1
protrusion 2 made of an insulating material arranged corresponding to 5;
2 and; a switch pressing spring 23 that biases the switch body 20 in a direction away from the terminals 19A, 19B;
and; a stay 24 that prevents the housing 18 from rotating in the rotational direction and allows movement in a linear direction in response to the opening and closing direction of the throttle valve; a head flange 26A is provided at one end; An adjustment screw 26 in which an intermediate locking collar part 26B is arranged with a gap H at one end, and a male thread part 26C is provided at the other end.
The intermediate shaft portion 26D between the head flange 26A of the twisted adjustment screw 26 and the intermediate locking flange 26B is connected to the stay 2.
The set is rotatably fitted into the support hole 24B drilled in 4, and the male screw portion 26C of the adjustment screw 26 is screwed onto the housing 18, and the set is contracted between the stay 24 and the head flange 26A. Housing 1 with spring 27
8 is suspended and the spring set load of the switch pressing spring 23 is made smaller than the spring force of the throttle valve return spring 16 when the throttle valve 13 is opened at idling.