JPS6014900Y2 - Centrifugal force governor for internal combustion engines - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an improvement of a centrifugal speed governor used in an internal combustion engine such as a diesel engine for a vehicle.

As vehicles become larger and faster, problems such as insufficient output of internal combustion engines at high speeds and smoke at low speeds have recently become a problem.

For this reason, for example, the fuel injection amount is increased by adapting to the rotational speed of the internal combustion engine in accordance with the amount of intake air in a predetermined high-speed operating state at full load of the internal combustion engine equipped with a supercharger. The present applicant has previously proposed a centrifugal force governor that can perform fuel control without impairing the function of a conventional centrifugal force governor in operating states of the engine other than those mentioned above. 52-8449).

The configuration according to this proposal is shown in FIG.

In the figure, 1 is a camshaft of a fuel injection pump for a diesel engine (not shown), and the flyweight 2 attached to the camshaft 1 is caused by centrifugal force as the engine speed increases. The sleeve 4 is opened using the pin 3 of No. 1 as a fulcrum, and the sleeve 4 is pressed rightward in the figure.

A guide lever 6 is attached to the shifter 5 protruding from the sleeve 4.
are connected by a second pin 7, and in response to the opening of the flyweight 2, the guide lever 6 moves counterclockwise in the figure from the position when the engine is stopped, using the fixed third pin 8 as a fulcrum. Rotate to.

Furthermore, the guide lever 6 has a link 9 connected to the fourth pin 1.
0, and the upper end of the link 9 is pressed against the notch 6a of the guide lever 6 by two torsion coil springs 11.

In addition, 12 in the figure is a floating lever.
As shown in the figure, it consists of an upper lever 12a and a lower lever 12b, and the lower end of the upper lever 12a and the lower lever 12
The upper end of b is connected to the link 9 by a fifth pin 13, a control rack 14 is connected to the upper end of the upper lever 12a by a ninth pin, and an eighth pin 27 is connected to the lower end of the lower lever 12b. Sliding lever 15 through
A control lever 16 is connected to a substantially middle portion of the sliding lever 15 by a tenth pin.

In addition, 17 in the figure is a governor spring, and the mounting lever 18
The flyweight 2 is tensioned between the flyweight 2 and the tension lever 19 to oppose the centrifugal force of the flyweight 2.

One end of a first rod 20 provided on the tension lever 19 is brought into contact with the tip of the shifter 5 by the elastic force of an idling spring 21 .

The other end 20a of the first rod 20 is attached to a second rod 23 which is held by the elastic force of the holding spring 22.
The first rod 20 comes into contact with the second rod 23 as it moves to the right in the figure.

Further, an adjusting screw 24 is screwed onto the middle part of the tension lever 19, and the link 9
Pressing one side of the

In FIG. 2, the torsion coil spring 11 mounted on the link 9 (indicated by a broken line) has a coiled portion 11a.
It has a linear part 11b and a hook-shaped part 11c,
The coiled part 11a is wound around the fourth pin 10, and one side of the outer periphery of the tip of the straight part 11b is brought into contact with the outer periphery-side surface 25a of the sixth pin 25 provided on the link 9, and , the tip of the hook portion 11c is brought into contact with the outer periphery and side surface of the seventh pin 26 fixed to the guide lever 6.

Further, the tip surface 2 of the adjusting screw 24
4a is capable of abutting on the other side surface 25b of the sixth pin 25 opposite to the side on which one side of the outer periphery of the tip of the straight portion 11b of the spring 11 abuts.

That is, both outer peripheral side surfaces 25a, 2 of the sixth pin 25
εb is pressed by the tip of the linear portion 11b of the torsion coil spring 11 and the tip surface 24a of the adjusting screw 24, respectively.

Further, as shown in FIG. 3, both side members 6b and 6c of the guide lever 6 are connected to each other between the upper lever 12a and the lower lever 12b of the floating lever 12 fixed to the fifth pin 13. are arranged in parallel.

Further, fourth, fifth and sixth pins 10, 13 and 2 are provided between the side members 6b and 6c of the guide lever 6.
5, both side members 9a and 9b of the link 9 are connected to each other, and between these both side members 9a and 9b, the torsion coil spring 11 is opposed to each other at a parallel interval with its linear portion 11b inside. It is arranged as follows.

1 to 3, when the rotation of the engine increases, the centrifugal force of the flyweight 2 compresses the idling spring 21, and the other end 20a of the first rod 20 is connected to the second rod 23.
The control rack 14 remains moved in the fuel increasing direction (to the left in FIG. 1) until it comes into contact with the second spring 22 and overcomes the elastic force of the second spring 22.

In this state, the tip end surface 24a of the adjusting screw 24 and the other side surface 25b of the outer periphery of the sixth pin 25 interposed between the both side members 9atOb of the link 9 come into contact.

When the engine speed further increases, the fly weight 2
The centrifugal force increases and overcomes the elastic force of the second spring 22, causing the shifter 5 to move to the right in FIG. It rotates counterclockwise in FIG. 1 using the fourth pin 10 as a fulcrum.

Therefore, the floating lever 12 is rotated counterclockwise in FIG. 1 using the fifth pin 13 as a fulcrum, and the control rack 14 is moved in the fuel increasing direction (to the left in FIG. 1) to adjust the fuel injection amount. Get an increase.

By the way, in the conventional centrifugal force governor configured as described above, as is clear from FIGS. Since the outer periphery and the side surface 25a are always in pressure contact with each other in a point contact state, the contact wear of these two members is significant. Since they are always in pressure contact with each other in a state of point contact, the wear of their respective contact surfaces is also significant.

FIG. 4 shows the influence on the control rack 14 when the above-mentioned wear occurs. The solid line in the figure shows the normal position characteristics of the control rack 14, and the broken line A shows the wear of the torsion coil spring 11. The broken line at the time shows the change in the positional characteristics of the control rack 14 when the adjusting screw 24 wears out.

As shown in the figure, when the torsion coil spring 11 wears out, the predetermined engine speed at which the injection amount increase starts decreases from N□ to N2.

Additionally, when the adjusting screw 24 wears out, the position of the control rack 14 moves from R1 to R2, causing a phenomenon in which the desired fuel injection amount is not reached at full load and high speed, weakening the function of the adjusting screw 24. A problem arises.

The present invention solves the above-mentioned problems and makes it possible to obtain the desired speed regulating effect.

Hereinafter, one embodiment of the present invention will be described in detail with reference to FIGS. 5 and 6.

It should be noted that in this embodiment, the same components in the drawings are denoted by the same reference numerals as those in the conventional art.

5 and 6 show the state when the engine speed increases, and in both figures, two torsion coil springs 11
The springs 11 are arranged with the left and right directions reversed, that is, with the straight portions 11b facing outside, compared to the conventional configurations shown in FIGS. 1 to 3.
1a is wound around the outer periphery of the fourth pin 10 that connects the link 9 and the guide lever 6 (indicated by a chain line), and the tip of the hook-shaped portion 11c is fixed to the guide lever 6. One side 2 of the outer circumferential surface of the first slider 28, which has a square cross section, is in contact with the outer circumference and the side surface, and the tip outer circumference and the side surface of the linear portion 11b are rotatably fitted to the sixth pin 25.
8a.

Further, the tip of the adjusting screw 24, which is screwed onto the center shaft of the tension lever 19 so that its position can be adjusted, is enlarged and its tip surface 24a is a smooth surface.

The tip end surface 24a of the adjusting screw 24 is in contact with one side 29a of the outer peripheral surface of a second slider 29 having a regular hexagonal cross section and rotatably fitted in the center of the sixth pin 25.

In the above configuration, since the wire of the torsion coil spring 11 generally has a circular cross section, one side of the outer periphery of the tip of the linear portion 11b and one side 28a of the outer periphery of the first slider 28 facing it are in line contact with each other. They are in contact with each other.

In addition, the tip surface 24a of the adjusting screw 24
and one side 29 of the outer peripheral surface of the second slider 29 facing thereto.
Since both a and a have a smooth surface shape, they come into surface contact with each other.

Note that the wire of the torsion coil spring 11 is formed to have a polygonal cross section (for example, a quadrangular cross section), so that one side of the outer circumference of the tip of the linear portion 11b of the spring 11 and one side 28a of the outer circumference of the first slider 28 are aligned with each other. They may also be in surface contact.

Furthermore, the first and second sliders 28 and 29 are connected to the sixth pin 25.
are rotatably mounted independently of each other, so
While the link 9 is pushed by the adjusting screw 24 as the engine speed increases and rotates counterclockwise around the fourth pin 10 in FIG. 5, one side 28a of the outer peripheral surface of the first slider 28 and torsion coil spring 11
There is always a constant line contact state or surface contact state between the tip end of the linear portion 11b and one side surface of the outer circumference, and between one side 29a of the outer circumferential surface of the second slider 29 and the tip end surface 24a of the adjusting screw 24. are always kept in constant surface contact.

As described above, according to the present invention, one side of the outer periphery of the tip of the linear portion of the torsion coil spring is brought into contact with one side of the outer periphery of the first slider whose outer periphery is polygonal, and the adjusting screw The distal end surface of the slider was brought into contact with one side of the outer peripheral surface of the second slider, which also has a polygonal outer peripheral surface, and the first and second sliders were respectively fitted to the pins so as to be rotatable independently of each other. Since the pressing force per unit area of the contact surfaces of the torsion coil spring, the eleventh and second sliders, and the pin is reduced, wear resistance is significantly improved, and a stable speed regulating function is achieved. can be maintained.

[Brief explanation of the drawing]

Figure 1 is a longitudinal cross-sectional view of a conventional centrifugal force governor, and Figure 2 is a longitudinal cross-sectional view of a conventional centrifugal governor.
Figure 3 is a partial enlarged view of the figure, Figure 3 is a partially cutaway view seen from the direction of the arrow ■ in Figure 2, Figure 4 is a view of the contact area between the link and the adjusting screw when wear occurs. A graph showing changes in fuel injection amount characteristics with respect to engine speed,
FIG. 5 is an enlarged view of a main part showing an embodiment of the present invention, and FIG. 6 is a partially cutaway view taken from the direction of the arrow {circle around (2)} in FIG. 1...Camshaft, 2-------Fly weight, 4...Crack/Sleeve, 5...Shifter, 6...
...Guide lever, 9...Link, 11...
...Torsion coil spring, 12...Floatin lever, 14...Control rack, 17...Governor spring, 19...
・Tension lever, 24...Adjusting screw, 25・Song・6th pin, 28・Song・1st
Slider, 29/Song/Second slider.

Claims (1)

[Scope of utility model registration request] a guide lever connected to the chic that converts the centrifugal force of the flyweight into an axial thrust; a tension lever that opposes the thrust of the chic by the tension of a governor spring; and a tension lever connected to the guide lever and the control rack of the injection pump to a floating lever that transmits the displacement of the lever to the control rack; a link having one end connected to the guide lever and the other end connected to the floating lever; a coiled part and a straight part; a torsion coil spring in which the coiled part is wound around a pin at one end of the link to press the link in one direction of the tension lever, and when the rotational speed of the internal combustion engine reaches a high speed range, the link A centrifugal force governor for an internal combustion engine is configured to rotate under pressure by the adjusting screw attached to the tension lever and move the control rack in a fuel increasing direction via the floating lever, First and second sliders each having a polygonal outer circumferential surface are fitted into pins provided on the link in contact with the spring and the adjusting screw, respectively, so as to be rotatable independently of each other; One side of the outer periphery of the tip of the linear portion of the spring is brought into contact with one side of the outer periphery of the first slider, and the tip end surface of the adjusting screw is brought into contact with one side of the outer periphery of the second slider. A centrifugal speed governor for an internal combustion engine, characterized in that the speed governors are in contact with each other.