JPS6338529B2 - - 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 adjust the throttle valve lever 5.
determine the minimum idling opening of the throttle valve 3, then screw the micro switch adjustment screw 7 to adjust the position relative to the micro switch 8, and when the throttle valve 3 reaches the idling opening, the micro A switch adjustment screw 7 is used to open or close a micro switch 8.

According to this 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. Also, since the ends of the throttle valve opening adjustment screw 6 and the micro switch adjustment screw 7 come into contact with the throttle valve lever 5, the throttle valve lever 5
It was necessary to increase the strength of the 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. Excellent workability for
An object of the present invention is to obtain a throttle valve idling opening detection device for a carburetor that has a high degree of design freedom in 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 thereof, and a terminal on 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 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 set to be smaller (weaker) than the spring force of the throttle valve return spring 16 when the throttle valve 13 is idling open.

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 periphery 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. In this state, insert the adjustment screw 26 with the flange 26A at the top into the support hole 24B of the stay 24, and insert the male thread 26B at the lower end of the adjustment screw 26 into the X screw of the housing 18. 18B, and the housing 18 is held suspended from the stay 24 by the flange 26A of the adjustment screw 26.

Furthermore, a set spring 27 is compressed between the upper surface 18D of the housing 18 and the lower surface 24C of the stay 24, and the spring set load of this set spring 27 is equal to the throttle valve return when the throttle valve 13 is opened at idling. The spring force is set to be larger (weaker) than the spring force of the spring 16.

Reference numeral 28 denotes an operating wire whose one end is locked to the throttle valve lever 15 and whose other end is connected to the accelerator operator shown in the figure.

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 at its idling opening, no counterclockwise pulling force is applied to the throttle valve lever 15 by the operating wire 28 . Therefore, the throttle valve lever 15 receives a clockwise rotational force by the throttle valve return spring 16, and the bent portion 15A of the throttle valve lever 15 is connected to the protrusion 22 of the throttle valve idling opening detection device 17.
comes into contact with.

According to this, the rotational force of the throttle valve 15 is
The signal is transmitted to the switch body 20 via. 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 applied to the throttle valve return spring 16.
Since the spring force is also set weak, the switch body 20 is mechanically transmitted to the stepped portion 18A of the housing 18 via the terminals 19A and 19B.

Although the housing 18 including the switch body 20 is about to move upward in the figure, the spring set load of the set spring 27 that presses the housing 18 toward the throttle valve lever 15 is transferred to the throttle valve 13. greater (stronger) than the spring force of the throttle valve return spring 16 at the idling opening of
Therefore, 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 lever 15 can be held at a constant position. 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 spring force of the throttle valve return spring 16, and the switch body 20 is brought into contact with the terminals 19A and 19B, as described above. Therefore, it was possible to close the electrical circuit.

Further, in order to adjust the idling opening degree of the throttle valve 13, the adjusting screw 26 is rotated.

For example, if the adjustment screw 26 is provided with a right-hand thread and the adjustment screw 26 is rotated clockwise, the housing 18 will be moved to the set spring 27 in accordance with the rotation of the adjustment screw 26.
It moves upward in the figure against the spring force of. This is because the locking portion 18C of the housing 18 is connected to the long groove 2.
This is because the rotation was suppressed at 4A.

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. Further, in the idling opening state maintained, the switch body 20 is 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 indexing the operating wire 28 from the throttle valve idling state (it rotates counterclockwise in the figure), the throttle valve lever 15 also rotates counterclockwise in synchronization with this, 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. Further, the adjustment operation can be performed by rotating the adjusting screw in one direction, and the operating direction is now single, thereby increasing the degree of freedom in design of the operating direction. Further, since the adjusting screw only needs to have a single contact point with the throttle valve lever, there is no need to make the throttle valve lever stronger than necessary, and the throttle valve lever can be made inexpensive, thereby reducing the overall price of the carburetor.

[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 cross-sectional view taken along the line - - in FIG. 2. 13... Throttle valve, 15... Throttle valve lever, 16
... Throttle valve return spring, 19A, 19B
...terminal, 24...stay, 24B...support hole,
26...adjustment screw, 26A...flange, 27...set spring.

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 linear movement in response to the opening and closing direction of the throttle valve; An adjustment screw 26 that is fitted and suspended from the stay 24 by the flange 26A, and whose other end is screwed onto the housing 18; 18 toward the throttle valve lever 15 side; the spring set load of the set spring 27 is made larger than the spring force of the throttle valve return spring 16 when the throttle valve 13 is idling, and the switch is pressed. A throttle valve idling position detection device for a carburetor in which the spring set load of the spring 23 is smaller than the spring force of the throttle valve return spring 16 when the throttle valve 13 is opened at idling.