JPS5899702A - Device for detecting opening degree of throttle valve - Google Patents

Abstract

PURPOSE:To detect the opening degree of the throttle valve of an internal combustion engine, by enlarging the rate of change of the resistance value of a resistor element, to which a slider that is rotated with the throttle valve as a unitary body in the region of the small opening degree of the throttole value is slidably contacted, larger than that in the other region. CONSTITUTION:When a specified power source is connected between lead wires 10A and 10B, the contact position of the resistor element 9 and the slider 6 is changed in proportion to the rotation of a shaft 3. Therefore, the voltage value is increased and decreased in response to the opening degree of the throttle valve. In this way, the width of the resistor element 9, to which the rotating tip part of the slider 6 is slidably contacted, is increased at a steep gradient up to a specified rotating position O2 from a rotation starting point O1. The part from the rotating position O2 to the end of rotation O3 has approximately the same width. The width of the element of the region theta of small opening degree (a low load region of the engine) from the point of zero opening degree to about 10 deg. of opening of the throttle valve 4 is abruptly changed as shown by a dotted line (b). The rate of change (change of width) of the cross sectional area of the resistor element 9, which determines the resistance value, is made larger that of the other opening region. A solid line (a) indicates the degree of change in the width of the conventional resistor element.

Description

[Detailed Description of the Invention] This invention is directed to the intake air amount (i.e. engine load) of an internal combustion engine.
Regarding the detection device/equipment for detecting the throttle valve opening by the opening degree of the throttle valve.
A predetermined air-fuel ratio can be obtained while measuring the amount of intake air.
The fuel injection amount is determined so that

To determine the amount of intake air, there are two methods: one is to measure the airflow in the intake passage, the other is to indirectly measure it from the throttle valve opening (or suction negative pressure) and the engine speed.The latter is especially linked to the accelerator pedal. The method of determining the engine load by detecting the throttle valve opening has the advantage of being mechanically simple.

This will now be explained based on FIGS. 1 and 2. A throttle valve 4 is fixed to a shaft 3 passing through the housing 1.

Five links connected to the naxel pedal are connected to one end of the gloss seat 3, and the opening degree of the throttle valve 4 is increased or decreased depending on the accelerator pedal distance.

Similarly, at the other end of the shaft 3, the base end of the slider 6 is integrally fixed by a nut 7, and slides into contact with a maple-shaped resistance plate 9 (resistance element).

In the figure, 10A and 10B are lead wires connected to the sliding element 6 and the resistor plate 9, and these are housed inside the box 8 attached to the side of the housing 1. When a predetermined power source is connected between 10A and 10B, the contact position between the resistance plate 9 and the slider 6 changes in proportion to the rotation of the shaft 3, so that the voltage value increases or decreases in accordance with the opening degree of the throttle valve. , Thereby, changes in the throttle valve opening degree, in other words, changes in the engine load, can be detected as electrical signals. (Patent application No. 54'-132624 filed by the same applicant) However, in such a conventional throttle valve opening detection device, the inner wall of the housing around the throttle valve 4' has a right cylindrical shape. Due to the structure of the throttle valve 4, the amount of intake air per unit rotation angle of the shaft 3 changes rapidly in the small opening range of the throttle valve 4. Taking into account the reduced precision and quality variations, there was a point where it was difficult to put it into practical use due to the strict requirements for lower fuel consumption unless processing accuracy was considerably improved.

This invention was made by focusing on such conventional problems, and by changing the element width and element material of the above-mentioned resistance element (resistance plate) in the direction of rotation of the slider, in particular, It is an object of the present invention to solve the above problem by increasing the change rate of the resistance value with respect to the rotation angle of the throttle valve in a small opening range of the throttle valve, thereby increasing the variation range of the output with respect to the flow rate.

Embodiments of the present invention will be described below with reference to the drawings.

As shown in FIG. 3, the element width of the resistance element 9 that the sliding tip of the slider 6 comes into sliding contact with is steep from the rotation base point O□ of the slider 6 to the predetermined rotation position 02. It is formed to increase in width, and is formed to have approximately the same width from the rotation position 02 to the rotation end point O.

In other words, the element width in the small opening area θ (low load area for a) from the 0 opening point of the throttle valve 4- to approximately 10 opening points suddenly changes as shown by the dotted line in FIG. The rate of change (width of change) of the cross-sectional area of the resistor element 9, which determines its resistance value, is larger than that in other operating regions.The solid line a in FIG. This shows the degree of change in the element width of the resistor element, which is approximately constant.

Since the other configurations are the same as those in FIGS. 1 and 2, detailed explanation will be omitted here with reference to FIGS. 1 and 2.

Since it is configured in this way, the lead wire 10A is now used.

When a predetermined power source is connected between 108 and 108, the contact position between resistance element 9 and slider 6 changes in proportion to the rotation of shaft 3, so it is natural that the voltage value increases or decreases depending on the throttle valve opening. This is as explained in FIGS. 1 and 2.

In this embodiment, as described above, in the small opening range θ of the throttle valve 4, the element width of the resistance element 9 is rapidly changed to □, thereby increasing the rate of change in resistance value. As shown by the dotted line in FIG. 5, the rate of change in the output voltage value also increases. ^
The solid line a in FIG. 6 shows the degree of change in the output voltage value in the conventional case. -As a result, due to the four-circle structure of the throttle valve mentioned above, even if the intake air amount changes rapidly in the small opening range, the resolution of the throttle valve opening and output voltage value can be adjusted in response to this change. Since the detection accuracy is increased, the detection accuracy is improved.

In addition, the simple structure of changing the resistor element width provides the above-mentioned high detection accuracy, and high processing accuracy is not required, making it possible to significantly reduce costs.

Next, FIGS. 6 and 7 (A) and (, B) show other embodiments of the present invention.

FIG. 6 shows an example in which the element width of the resistive element 9 is formed so as to rapidly increase toward the rotation reference point O8 of the slider 6 in the small #@ epidemic region θ, contrary to the above-mentioned FIG. 3. With this, a large rate of change in resistance value can be obtained as in FIG. 3.

Figures 7 (A) and (B) show that the rate of change in resistance value is not obtained by changing the width of the resistor element as in Figures 3 and 6 above. The rate of change in resistance value is obtained by combining the above element materials 9 and 9A.

In other words, by increasing the proportion of the element material 9A having a large specific resistance in the small opening area of the throttle valve 4, the rate of change in resistance value in the small opening area can be adjusted to the same level as in FIGS. 3 and 6. It can be made bigger.

Figures 7 (A) and (B) show the difference in how they are combined; Figure 7 (A) is an example of combining them with emphasis on the element width, and Figure 7 (B) is an example of combining them with emphasis on the element thickness. However, since the rate of change in the cross-sectional area of the resistive elements 9 and 9A, which determines the resistance value, is the same, similar effects can be obtained. In this example,
There is an advantage that the characteristic of the output voltage value with respect to the throttle valve opening shown in FIG. 5 can be changed freely depending on how the boundary line C in FIGS. 7(A) and 7(B) is provided.

As explained above, according to the present invention, the element width and element material of the resistance element are changed in the rotating direction of the slider, thereby providing resistance to the rotation angle of the throttle valve, especially in the small opening range of the throttle valve. By increasing the rate of change of the value, the resolution of the throttle valve opening and output voltage values in the small opening range is increased, and the detection accuracy in the low load range with a small amount of intake air, which had previously been degraded, has been improved. The effect of further improvement can be obtained.

[Brief explanation of the drawing]

Figure 1 is a plan view of the conventional device, Figure 2 is a side view of its main parts,
FIG. 3 is a side view of the main part of the embodiment of the present invention, FIGS. 4 and 5 are explanatory diagrams for comparison with the conventional example showing the resistance element width and the rate of change in the output voltage value, and FIG. FIG. 7(A) is a side view of the main part of the second embodiment, and FIG. 7(A) is a side view of the main part of the third embodiment, and FIG. 7(B) is a sectional view of the resistor element thereof. 4... Throttle valve, 6... Slider, 9, 9A... Resistance element, θ... Small opening area of throttle valve. Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 4 Class valve opening 7L (S) Fig. 5 Fig. 6 Fig. 7 (A) Fig. 7 (B) 7 Valve opening degree (→)

Claims (1)

[Claims] The rotation angle of the throttle valve, which controls the intake air amount of the internal combustion engine in conjunction with the axle, is electrically detected by changes in the resistance value of the resistance element that the φ slider, which rotates integrally with the throttle valve, makes sliding contact with. A throttle valve opening detection device characterized in that the throttle valve opening is increased at least in a small throttle valve opening region. .