JP2519452B2 - Boost compensator for diesel engine with supercharger - Google Patents

Description

TECHNICAL FIELD The present invention relates to a boost compensator for a diesel engine.

(Prior art and its problems) In an engine equipped with a supercharger, during rapid acceleration, a rise in pressure by a turbocharger turbine is delayed with respect to a rise in rotation speed, that is, a supercharge delay is caused, resulting in a shortage of fuel air. This can lead to excessive fuel supply during rapid acceleration, causing black smoke to be generated.

The boost compensator is provided to deal with the above-mentioned excessive fuel supply, and prevents excessive fuel during sudden acceleration and prevents generation of black smoke.

However, it is necessary to release the fuel limitation by the boost compensator at the time of engine start, especially at low temperature start, in order to ensure startability. In the conventional boost compensator, it has to be released by rotating the boost lever toward the fuel increase side against the spring in the compensator case, and the release operation is heavy.

(Object of the Invention) An object of the present invention is to lighten the operation of releasing the boost compensator.

(Technical Means for Achieving the Purpose) In order to achieve the above-mentioned object, the present invention provides the other end of the boost lever whose one end engages with the slider rod.
The boost pressure release lever shaft is provided with an eccentric shaft portion that is eccentric from the lever shaft for making abutting contact with a fuel injection amount adjusting member such as a fuel increasing / decreasing rack or a governor lever connected to the fuel increasing / decreasing side. , The intermediate portion of the boost lever is rotatably supported by the eccentric shaft portion, and the boost pressure release lever shaft is rotatably operable from the outside around the lever shaft center, and the eccentric shaft portion is rotated by the rotation of the lever shaft. The boost lever is rotated about its axis, and the other end of the boost lever is separated from the adjusting member with one end of the boost lever as a fulcrum of rotation.

(Embodiment) FIG. 1 is a vertical sectional view of a governor to which the present invention is applied. In FIG. 1, the governor case 3 is fixed to a front end portion of a fuel injection pump case 4, and is mounted inside the governor case 3. The camshaft 11 for operating the fuel injection pump extends, and the front end of the camshaft 11 supports the cabana sleeve 6 movably in the axial direction, and the support 13 supports the cabana weight 5 via the support shaft 14.
Is rotatably supported. The governor weight 5 is in contact with the governor sleeve 6, and the governor weight 5 expands due to an increase in the number of rotations of the cam shaft 11 to push the governor sleeve 6 forward.

A governor lever shaft 17 that is substantially perpendicular to the cam shaft 11 is fixed to the governor case 3 at a position slightly higher than the cam shaft 11, and the governor lever 7, the tension lever 8, and the thrust lever 9 are rotatable on the governor lever shaft 17. It is supported by. A link 19 is pivotally connected to the upper end of the governor lever 7, and a fuel increasing / decreasing rack 20 is pivotally connected to the tip end of the link 19 so that the fuel increasing / decreasing rack 20 extends toward the fuel injection pump 1 side. It meshes with a fuel increase / decrease pinion (not shown) of the injection pump 1.

The tension lever 8 is formed in an inverted "L" shape, and a governor spring 10 is stretched between the rear upper end and a front end of the front inner accelerator control lever 22.
Is being urged to increase fuel. The control lever 22 is fixed to a control shaft 24, and the control shaft 24 is rotatably supported by the governor case 3 and extends outside the governor case 3, and the outer end portion thereof has an outer control lever as shown in FIG. 23 is stuck.

In FIG. 3 showing an exploded perspective view of the governor, the governor lever 7 is formed in an upward U-shape by a pair of left and right lever portions 7a and 7b and a planar connecting portion 7c that integrally connects their lower ends. Both lever portions 7a and 7b are rotatably supported on the governor shaft 17 via the tubular metal 42.
One governor lever portion 7a extends upward and is pivotally connected to the link 19 as described above, and the other governor lever portion 7b has a set spring 25 between its upper rear end and the upper front end of the thrust lever 9. The upper front end 7d of the governor lever portion 7b is engaged with the projection 9b at the upper front end of the thrust lever 9 by the tensile force of the set spring 25.

The thrust lever 9 is also formed in an upward U shape from a pair of left and right lever portions and a connecting portion 9a that integrally connects the lower end portions thereof, and the thrust lever 9 as a whole has both ends of the cylindrical metal 42. It is supported by the governor shaft 17 via the. As shown in FIG. 1, a shifter 26 is fixed to the lower end connecting portion 9a of the thrust lever 9, and the shifter 26 comes into contact with the governor sleeve 6 to receive a governor force.

The lower end of the tension lever 8 has a recess 27 having an open rear end.
A start spring 28 projecting backward is disposed in the recess 27, and the rear end of the start spring 28 is in contact with the connecting portion 9 a of the thrust lever 9.

Reference numeral 31 denotes a fuel limiter which limits the maximum amount of rotation of the tension lever 8 in the fuel increasing direction.

As a stop mechanism for stopping the engine, a stop lever 32 is arranged on the front side of the governor lever 7, and the stop lever 32 includes a cam portion 32a having a semicircular cross section.
2a faces the front end edge of the upper half of the governor lever 7.
The stop lever 32 is rotatably supported by the governor case 3, extends out of the governor case 3, and integrally has a stop handle 36. That is, the stop lever 32
By rotating, the governor lever 7 alone can be rotated toward the fuel reduction side.

In FIG. 1, a boost compensator 40, which is an essential part of the present invention, includes a slider rod 47, a compensator case 48, a compensator case lid 49, and two coil springs 5.
6, 57, a rubber diaphragm 51, a boost lever 45 and the like. The compensator case 48 is formed integrally with the governor case 3 on the upper part of the governor case 3, and the case lid 49 is detachably fixed to the front end of the compensator case 48.

The outer peripheral end of the rubber diaphragm 51 is sandwiched between the compensator case 48 and the case lid 49, and the inside of the case 48 is partitioned into a boost pressure chamber 61 at the front end and a spring chamber 53 on the rear side. The inner circumference of the rubber diaphragm 51 is the front and rear washers 75, 76.
It is arranged between the washers 75 and 76 by rivets 77. Further, a contact plate 78 is provided on the rear surface of the rear washer 76.
Is also fixed.

The boost pressure chamber 61 is a turbocharger via a boost pressure introduction pipe.
It is connected to the pressurized air supply passage 55 so as to increase the pressure in the boost pressure chamber 61 in response to an increase in the turbine rotation speed of the supercharger 55.

The slider rod 47 is arranged parallel to the cam shaft 11 and is supported by the boss portion 48a of the case 48 so as to be movable in the front-rear direction, and the spring washer 73 is fixed to the front end portion of the rod 47. The front end spring washer 73 is a contact plate 78 for the diaphragm 51.
The rear end of the rod is integrally provided with a pair of holding plates 54.

With respect to the two springs 56 and 57 in the spring chamber 53, the outer first spring 56 has a large coil diameter but a small wire diameter and a small spring constant, while the inner second spring 56 is used. 57 has a small coil diameter but a large wire diameter and a large spring constant. The first spring 56 is contracted between the washer 76 on the rear side of the diaphragm 51 and the rear surface of the compensator case 48, and the load adjusting shim 58 is arranged between the first spring 56 and the rear surface of the compensator case 48. Has been done. That is, by removing the case lid 49, the diaphragm 51 and the first spring 56 can be extracted. The second spring 57 is contracted between the front end washer 73 of the slider rod 47 and the brim of the boss portion 48a. 70 is a stopper bolt, which restricts the maximum amount of movement forward of the diaphragm 51.

An intermediate portion of the boost lever 45 is rotatably fitted and supported by the eccentric shaft portion 44, and the upper end pin of the boost lever 45 is supported.
46 is held between the holding plates 54 of the slider rod 47. The lower end bent portion 45a of the boost lever 45 faces the front end edge of the governor lever 7 so as to be engageable from the front.

As shown in FIG. 3, the eccentric shaft portion 44 is integrally formed with the release lever shaft 43, and is eccentric upward from the release lever shaft center. By rotating the release lever shaft 43 in the direction of arrow A, the boost lever shaft 43 is boosted. The lever 45 can be moved in the direction of arrow B (forward) around the upper end pin 46 as the center of rotation.

The release lever shaft 43 is a governor case 3 as shown in FIG.
A boost pressure release lever 66 is integrally provided so as to be rotatably supported by the boost pressure release lever 66 and extend outward. Release lever 66
A spring 80 is stretched between the spring locking portion 79 of the governor case 3 and the governor case 3, and the release lever 66 is stretched by the spring 80.
Is urged in the direction opposite to the direction of arrow A in FIG. The release lever 66 is rotated against a spring 80 manually or by an appropriate actuator such as a solenoid valve.

The operation will be described. First, the operation when the action of the boost compensator 40 is not released will be explained. When the engine is stopped, the slider rod 47 is moved forward by the force of the springs 56 and 57 as shown in FIG. The lower end bent portion 45a of 45 is moved to the fuel reduction side (rear side).

After the engine is started, the pressure of the boost pressure chamber 61 increases in proportion to the boost pressure of the supercharger 55, so that the slider rod 47 resists the elastic force of the springs 56 and 57 and is proportional to the increase of the boost pressure. Move backwards, boost lever 45
Is rotated in the direction of arrow B (clockwise) around the eccentric shaft portion 44, and the lower end bent portion 45a is moved to the fuel increase side.

When the engine is suddenly accelerated, a so-called supercharging delay occurs on the way, so that the air supply is insufficient and the fuel tends to be excessive. However, since the boost pressure is delayed to increase, the rearward movement of the slider rod 47 is small in proportion to the boost pressure, and therefore the governor lever 7 is restricted from moving toward the fuel increasing side by the lower end bent portion 45a of the boost lever 45. As a result, excessive fuel supply is prevented and black smoke is prevented from being generated.

When the engine speed approaches the specified speed and the air supply amount becomes sufficient, the slider rod 47 moves further rearward, moving the bent portion 45a of the boost lever 45 to the fuel increasing side, and the governor lever 7 moves. Allowing rotation to the fuel increase side,
Sufficient fuel can be supplied to the specified speed.

At the time of low-temperature start, etc., the boost compensator 40 is started in a released state to secure an increased fuel amount at the time of start.

If you want to cancel the boost compensator 40,
By rotating the release lever 66 in the figure against the spring 80, the release lever shaft 43 in FIG. 1 is rotated in the direction of arrow A to move the eccentric shaft portion 44 around the lever axis in the direction of arrow A (forward direction). ), Thereby rotating the boost lever 45 in the direction of arrow B with the upper end pin 46 as a fulcrum. Therefore, the lower end bent portion 45
The a is separated from the front edge of the governor lever 7 to the front side, and the action of the boost compensator 40 is released. In the releasing operation, since the upper end pin 46 of the boost lever 45 serves as a fulcrum, it is not necessary to compress the springs 56 and 57, and the releasing operation is light.

For fine adjustment of the operating characteristics of the diaphragm 51, simply remove the case lid 49 shown in FIG. 1, pull out the outer first spring 56 together with the diaphragm 51, and adjust the number or thickness of the shims 58 to easily operate the diaphragm. The characteristics can be adjusted.

(Another embodiment) In the embodiment shown in FIGS. 4 and 5, a boost lever 45 is provided at the rear end of the fuel increasing / decreasing rack 20 (the end opposite to the governor).
This is an example in which the lower end portion 45a of the is engaged. In FIG. 4, the front and back are opposite to those in the case of FIG.

The boost compensator case 40 is fixed to the rear end portion of the fuel injection pump case 4, and the slider rod 47 is provided so as to extend downward. An abutment plate (nut with collar) 54 is fixed (screwed) to the lower end of the slider rod 47, and an abutment plate (nut with collar) 90 is fixed (screwed) to the rear end of the fuel increasing / decreasing rack 20. ) Has been. The boost lever 45 is formed in an inverted L shape and is rotatably supported by a horizontal eccentric shaft portion 44. The lower end portion 45a of the boost lever 45 is attached to the contact plate 90 of the rack 20 from the front side (fuel increase side). The rear end portion 46 is in contact with the plate 54 of the slider rod 47 from above. The eccentric shaft portion 44 is formed integrally with the release lever shaft 43, and is eccentric to the rear lower side from the release lever shaft center.

Release lever 66 provided integrally with the release lever shaft 43
Is urged by a spring 80 in the direction opposite to the arrow A direction in FIG. The other structure is similar to that of FIG. 1, and the same parts as those in FIG. 1 are denoted by the same reference numerals.

According to the structure of FIGS. 4 and 5, boost compensator
You can easily secure enough space for 40.

In the case of FIG. 4, by rotating the release lever 66 in the direction of arrow A, the eccentric shaft portion 44 is moved forward (fuel increase side), whereby the lower end portion 45a of the boost lever is brought into contact with the contact plate 90. To release the boost compensator action.

(Effects of the Invention) According to the present invention as described above: (1) When the boost lever 45 is rotatably supported by the eccentric shaft portion 44 that is eccentric from the release lever shaft 43 to release the action of the boost compensator 40. Since the release lever shaft 43 is rotated to rotate the boost lever 45 with one end on the slider rod side as a rotation fulcrum, the spring members 56, 57, etc. in the boost compensator 40 are No need to compress, no need for large operating force,
Release operation becomes light.

(2) With the boost compensator 40, the boost lever 45 is configured to move to the fuel increase side in comparison with the increase in boost pressure, so even if a supercharging delay occurs during sudden acceleration, the supercharging delay will be delayed. Correspondingly, the boost lever 45 restricts the rotation of the governor lever 7 toward the fuel increase side, whereby excessive fuel supply can be prevented and black smoke can be prevented from occurring during sudden acceleration.

(3) As a support mechanism for releasing the boost pressure, an eccentric shaft structure, that is, a large-diameter lever shaft 43 is made rotatable, and an eccentric shaft portion 44 having a smaller diameter is formed on the lever shaft 43. The eccentric shaft portion 44 is rotated about the lever axis by rotating the., And thereby the intermediate portion of the boost lever 45 is rotatable and displaceable. Therefore, the support structure of the boost lever 45 is simple and the assembly is easy. It becomes easier and saves cost.

(4) Since the other end of the boost lever 45 is only opposed to the governor lever or the like from the fuel increase side, during operation,
When the boost pressure is high, the other end of the boost lever 45 is separated from the governor lever or the like toward the fuel increasing side, and the force relationship is broken.

Therefore, it is possible to reduce the unreasonable force applied to the governor lever and the like from the boost lever, and it is not necessary to consider it as a strong member.

(5) Since one end of the boost lever 45 engages the boost compensator 20 with the slider rod 47 and the other end faces the governor lever or the like, rather than connecting the boost compensator to an intermediate portion of the boost lever, for example. In addition, the degree of freedom of the arrangement location is widened, and the conventional governor lever can be mounted without changing the structure of the governor lever, and the versatility is enhanced.

[Brief description of drawings]

1 is a longitudinal sectional view of a mechanical governor according to the present invention, FIG. 2 is a II-II sectional view of FIG. 1, FIG. 3 is an exploded perspective view of a governor mechanism, and FIG. 4 is a longitudinal section of another embodiment. FIG. 5 is a sectional view taken along line VV of FIG. 7 ... Governor lever (an example of fuel adjusting member), 20 ... Fuel increasing / decreasing rack (another example of fuel adjusting member), 40 ... Boost compensator, 43 ... Release lever shaft, 44 ... Eccentric shaft part, 45 ...... Boost lever,
47 …… Slider rod, 55 …… Supercharger, 56,57 …… Spring

Claims (1)

(57) [Claims] 1. A boost compensator in which a slider rod is slidably provided in a compensator case and the slider rod is actuated against a spring member in the case by boost pressure from a supercharger. One end of the slider rod is the slider rod. The other end of the boost lever that engages
The boost pressure release lever shaft is provided with an eccentric shaft portion that is eccentric from the lever shaft for making abutting contact with a fuel injection amount adjusting member such as a fuel increasing / decreasing rack or a governor lever connected to the fuel increasing / decreasing side. , The intermediate portion of the boost lever is rotatably supported by the eccentric shaft portion, and the boost pressure release lever shaft is rotatably operable from the outside around the lever shaft center, and the eccentric shaft portion is rotated by the rotation of the lever shaft. A boost compensator for a diesel engine with a supercharger, characterized in that the boost lever is rotated about its axis, and one end of the boost lever is used as a rotation fulcrum to separate the other end of the boost lever from the adjusting member.