JP2592992Y2 - Fuel control mechanism with boost compensator for fuel injection pump - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel control mechanism of a distribution type fuel injection pump having a boost compensator for increasing a fuel injection amount.

[0002]

2. Description of the Related Art In a diesel engine equipped with a supercharger, a boost compensator (hereinafter referred to as "boocon") is provided in a fuel injection pump for supplying fuel to the engine, and the intake of the supercharger during high-speed rotation of the engine. It is known that the fuel injection amount is increased in response to the increase in the amount (Japanese Utility Model Laid-Open No. 1-139038). According to this, for example, as shown in FIG. 7, the fuel injection amount characteristic of the fuel injection pump having no boucon is abcd.
While there was a -e-f, changing the d-d'-e'-e- f when the rotational speed of the engine the fuel injection quantity characteristic of the fuel injection pump having a boost compensator exceeds N ₂ Becomes possible.

[0003]

However, in the conventional fuel injection pump with a boucon, if the fuel injection amount at the time of high-speed rotation is to be obtained so as to obtain the characteristic of dd'-e'-e, the fuel injection amount at the time of startup is low. A'-b '
Injection amount Q ₃ or become more shown in the section, there will issue greatly beyond the proper injection quantity Q ₂ in the prior art. On the other hand, the fuel injection amount at the time of starting is adjusted to the appropriate value Q ₂
When you suppress the fuel injection amount at the time of high-speed rotation is also not only possible to increase the Q ₂ to the same level, to increase the amount of properly fuel injection in response to the intake air amount of the increase due to the turbocharger could not.

In order to solve the above problem, the present invention proposes a fuel injection pump capable of sufficiently increasing the fuel injection amount during high-speed rotation while maintaining a proper fuel injection amount at the time of starting. It is an object to provide a fuel control mechanism with a boost compensator. Ma
In addition, regardless of the manufacturing error and assembly error of each part ,
The challenge is to be able to fine-tune the fuel injection amount.
I have.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, the gist of the present invention is to provide a boost compensator having a boocon lever which rotates to increase fuel in accordance with an increase in boost pressure; A tension lever whose rotation to the side that increases fuel is restricted by contact with the boucon lever, and rotates integrally with the tension lever during operation of the engine, and increases the fuel in the initial stage of engine startup. A fuel control mechanism with a boost compensator of a fuel injection pump having a governor mechanism having a start lever that increases the fuel injection amount at the start of startup by independently rotating to the side to perform the tension lever and the start lever. A first shaft which is rotatably supported on a first shaft as a support shaft and has a different axis from the first shaft on the start lever. The shaft is provided, on the circumferential surface of the second shaft that was attached an adjustment auxiliary member for restricting the rotation amount of the fuel increase side of the start lever by contacting with the boost compensator lever initial start of the engine It is characterized by.

[0006]

Therefore, during operation of the engine, the start lever and the tension lever rotate integrally, and when the boocon lever is rotated to increase fuel, the rotation of the tension lever to increase fuel is performed. The dynamic amount also increases, and a fuel injection amount commensurate with the increase in boost pressure can be obtained.
On the other hand, in the early stage of starting the engine, the start lever separates from the tension lever and pivots independently to the side that increases the fuel, so that there is a possibility that the fuel injection amount at the time of an appropriate start can be greatly exceeded. but, this start-up initial, Ru can be adjusted auxiliary member provided on the second shaft of the start lever for regulating the fuel injection amount at the time of starting by impinging on the boost compensator lever. Fuel injection during this start
The amount is the same for each part, even for the same standard fuel injection pump.
Variations due to manufacturing errors and assembly errors
However, the adjustment assisting member attached to the second shaft is
Different sizes and shapes can be arbitrarily selected.
As a result, the fuel injection amount at the start
It is possible to adjust the strictly by selecting
You.

[0007]

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

FIG. 1 shows a fuel injection pump 1 that uses a boost compensator to mechanically compensate fuel injection amount control by a governor mechanism.

The fuel injection pump 1 supplies fuel from a fuel tank to a chamber 2 by a feed pump (not shown). A plunger 3 is slidable on a plunger barrel 5 fixed to a pump housing 4. It is attached to. The base of the plunger 3 abuts and engages with the cam disk 6 and is pressed by a plunger spring 7. The cam disk 6 is engaged with the drive shaft through a coupling so as to allow the cam shaft 6 to move in the axial direction. The rotation of the cam disk 6 causes the reciprocating movement of the plunger 3 for the suction pressure feeding of the fuel. And rotation for distributing the fuel.

In the suction step in which the plunger 3 moves to the left in the drawing, the fuel in the chamber 2 flows from the suction port 8 to the suction groove 9 formed in the axial direction of the tip of the plunger 3.
Is supplied to the pump chamber 10 surrounded by the plunger barrel 5 and the plunger 3 through one of the pump chambers. At the time of the pumping step in which the plunger 3 moves to the right in the drawing, the suction port 8 and the suction groove 9 are separated from each other, The fuel compressed in 10 is sent from the distribution port to the delivery valve 12 through the vertical hole 11 of the plunger 3, and is injected from the injection nozzle into the cylinder of the engine.

The plunger barrel 5 of the plunger 3
The control sleeve 13 is slidably fitted to the portion protruding from the plunger 3, and when the cutoff port 14 communicating with the vertical hole 11 of the plunger 3 comes off the edge of the control sleeve 13 and opens into the chamber 2, it is compressed. Since the fuel flows out into the chamber 2, the delivery of the fuel to the injection nozzle is stopped, and the injection ends. Therefore, the injection end, that is, the injection amount can be adjusted by adjusting the position of the control sleeve 13, and the injection amount increases as the control sleeve 13 moves to the right (A direction) in the figure, and moves to the left (B direction). The injection amount can be reduced as the distance is increased.

The boost compensator 15 is provided on a mounting case 16 that forms the upper part of the pump housing 4 and has a diaphragm 17 sandwiched by a case member that forms the mounting case 16 inside the case. The inside of the case is communicated with the outside by the diaphragm 17, and an atmospheric pressure chamber 18 set to the atmospheric pressure and a boost pressure chamber 19 into which the pressure (boost pressure) of the intake air supplied from the supercharger to the engine is introduced. Is divided into In the diaphragm 17,
A rod 20 extending toward the atmospheric pressure chamber is fixed, and a spring 21 disposed in the atmospheric pressure chamber 18 applies a spring force to the boost pressure chamber. For this reason, the rod 20 stops at a position where the boost pressure, the atmospheric pressure, and the spring force of the spring 21 are balanced. When the boost pressure increases with the rotation of the engine, the lower portion (C in FIG. Direction).

In the vicinity of the lower end of the rod 20, there is formed a tapered portion 22 whose diameter gradually decreases toward the upper end, and one end of a pin 23 movable in the radial direction of the rod 20 is formed on the tapered portion 22. Has been abutted. The other end of the pin 23 is in contact with the upper end of the boocon lever 24 that is supported by the pump housing 4.

The governor mechanism 25 is connected to the control sleeve 13 to displace the sleeve.
As also shown in FIGS. 2 to 5, mainly the collector lever 26, a tension lever 27 provided inside the collector lever 26, a start lever 28 provided inside the tension lever 27, and a And an Angleich lever 29 provided.

The collector lever 26 is configured such that both side surfaces 30a and 30b of a lower end portion 30 formed in a U-shape are formed by the plunger 3.
Pivot pin (axial center M ₁ ) extending in the direction perpendicular to the axial direction of
Thereby, the pump housing 4 is rotatably attached to the pump housing 4. The collector lever 26, as seen in FIG. 1, the site below the M ₁ is biased to figure leftward by support spring 31 interposed between the pump housing 4, the lower end of the collector lever 26 Part 30
The upper end of the lever portion 32 extending upward from the support case 31 is strongly pressed against the adjusting screw 33 of the mounting case 16 by the spring force of the support spring 31.
For this reason, the collector lever 26 can be rotated about the M ₁ only by adjusting the amount of protrusion of the adjusting screw 33 from outside the pump housing 4.

The tension lever 27 is in the lower than M ₁ collector lever 26, is rotatably supported on the first shaft (axis M ₂₎ 36 to inserted the lower end sides. A control lever 3 attached to the pump housing 4 is provided above the tension lever 27.
4, the tension of the governor spring 35 is added. When the control lever 34 is rotated in the fuel increasing direction, the tension of the governor spring 35 increases, and the tension lever 27 ₂ is rotated to the control lever side (D side). On one side surface of the tension lever 27, an expansion portion 38 which is expanded so as to cover a second shaft (axis M3) 37 described below is formed.

The start lever 28 is rotatably supported by the first shaft 36, and has a ball head pin 39 at its lower end which is fitted into the pin hole 13a of the control sleeve 13. The surface of the portion of the start lever 28 facing the tension lever 27 is not formed, and an extended portion 40 bent and extended from the side surface is provided on the upper portion. A spring receiver 42 of a start idle spring 41 interposed therebetween is provided, and one end of a start spring (leaf spring) 43 is fixed. The other end of the start spring 43 is in contact with the tension lever 27, and the tension lever 27 is
8 is always urged in a direction to be separated from it.

The Angleich lever 29 is rotatably supported by a second shaft 37 into which both upper side surfaces of the start lever 28 are inserted. This Angleich lever 29
At the lower part of the projection, a projection mounting portion 44 bent in a U-shape is provided, on which a first projection 46 urged in the direction of the tension lever 27 by an Angleich spring 45 is provided.
It is inserted so as to allow a predetermined amount (L2) of movement in the axial direction. Further, the back surface portion which is located below the M ₃ of Angleich lever 29, the second protrusion 47 which protrudes in the direction of the tension lever 27 is fixed.

A governor shaft 50 extending along the plunger 3 is fixed to the wall of the pump housing 4. The governor shaft 50 is provided with a gear 51 that rotates with the rotation of the drive shaft, and a fly weight holder 52 that rotates integrally with the gear 51 is provided. At the tip of the governor shaft 50, a governor sleeve 53 that is movable in the axial direction is provided.
In the fly weight holder 52, a fly weight 54 that opens outward when a centrifugal force is generated is provided. The governor sleeve 53 is pushed out when the flyweight 54 is opened, and its tip abuts between the first projection 46 and the second projection 47 of the Angleich lever 29, and the Anglerich lever 29 is moved to the tension lever 27. (E direction).

The boucon lever 24 has an intermediate portion rotatably attached to a shaft (axis M ₄ ), and a contact portion 55 at the lower end thereof for restricting the movement of the tension lever 27 and the start lever 28 of the governor mechanism 25. Are formed. That is, the boocon lever 24 has a shape in which a portion below M4 protrudes laterally beyond the bulging portion 38 of the tension lever 27, and the tip portion bent along the axial direction of the second shaft 37. , A contact portion 55 is formed. In this contact portion 55, the bush 56 externally fitted to one end of the second shaft 37 and the bulging portion 38 of the tension lever can come into contact. Here, bush 56
Is rotated integrally with the start lever 28,
The bush 56 allows the start lever to increase fuel.
The adjustment assisting member according to the present invention for restricting the amount of rotation of the adjusting member is constituted. When the rod 20 moves downward, one end of the pin faces the tapered portion 22, so that the pin 2
3 allows movement in the I direction in FIG. 1 and allows the boucon lever 24 to rotate clockwise (F direction).
The contact portion 55 can be moved in a direction in which the movable range between the tension lever 27 and the start lever 28 is increased.

Next, the operation of the injection pump in the above configuration will be described.

First, when the engine is started, the tension lever 27 is pulled by the governor spring 35, and the bulging portion 38 of the tension lever 27 contacts the contact portion 55 of the boocon lever 24. In addition, the start spring 43 rotates the start lever 28 in the G direction with the M2 as a fulcrum so that the start lever 28 separates from the tension lever 27, and the governor sleeve 53 is pushed in the retreating direction (H direction). The bush 56 is in contact with the contact portion 55, and the amount of rotation of the start lever 28 is restricted. For this reason, at the time of starting, the control sleeve 13 moves in the direction (A direction) in which fuel is increased, but the control sleeve 13 does not move to the movement limit position, and stops at the position where the bush 56 contacts the boocon lever 24. Then, the fuel injection amount is set to Q2 defined by ab on the characteristic line in FIG.

From this state, when the rotation speed of the engine gradually increases and falls within the range of N1 to N2, the flyweight 5
4, the governor sleeve 53 is pushed out, the Angleich lever 29 rotates around M3, the first projection 46 hits the tension lever 27, and the Anglerich lever 29 starts around this point. The lever 28 is pushed rightward, and the second protrusion 47 also comes into contact with the tension lever 27.
Together with M2 as a fulcrum. The tension lever 27 includes first and second projections 46,
The urging force from the governor sleeve 53 is received through the lever 47, and the tension of the governor spring 35 is received in a direction opposite to the urging force. For this reason,
When the control lever 34 is rotated to the maximum load state, the tension by the governor spring 35 increases, the tension lever 27 rotates in the direction D with the M2 as a fulcrum, and the bulging portion 38 of the tension lever 27 It stops when it comes into contact with the contact portion 55 (see FIG. 6). However, in this case, since the start lever 28 is integrated with the tension lever 27, the gap L1 is provided between the contact portion 55 of the boocon lever 24 and the bush 56.
(Corresponding to a start stroke), the control sleeve 13 is located at a position shifted in the B direction from the initial stage of the start, and the injection amount at the time of the maximum load decreases as compared with the initial stage of the start.
Q1 defined by cd on the characteristic line in FIG. 7 is the fuel injection amount in this state.

When the boost pressure further rises from this state, the diaphragm 17 is pushed toward the atmospheric pressure chamber, and the rod 20 moves downward (in the direction C), allowing the pin 23 to move in the direction I. Accordingly, the boucon lever 24 is allowed to move in the F direction. Therefore, the tension lever urged in the direction D by the tension of the governor spring 35 causes the boocon lever 24 to rotate in the direction F. Since the start lever 28 rotates integrally with the tension lever 27, the control sleeve 13 moves in the direction A with the rotation, and the fuel injection amount increases (section dd ′).

This increase in the injection amount is until the boost pressure rises, the rod 20 moves to the movable limit position, and the boocon lever 24 is fully rotated in the F direction. 27 also stops, so that the injection amount remains constant at Q3 even when the boost pressure further increases as the rotational speed increases (section d′−
e ').

Although not shown in the characteristic diagram of FIG. 7, when the engine speed further increases, the Angleich lever 29 is opposed to the Angleich spring 45 with the second projection 47 as a fulcrum. The first protruding portion 46 is rotated to reduce the protruding amount of the first protruding portion 46 by L2 (reverse Angui stroke).
Therefore, the start lever is slightly rotated in the counterclockwise direction (G direction), and the control sleeve is further moved rightward (A direction), so that the injection amount can be increased to Q3 or more. .

When the engine speed further rises beyond N4, the governor sleeve 53 is pushed further to the right, and the Angleich lever 28 is strongly pushed to push the tension lever 27. The fuel is moved in the J direction against the governor spring 35, and the injection amount gradually decreases (section e′-ef).

As described above, the rotation of the tension lever 27 and the start lever 28 is restricted.
And the bush 56 provided on the start lever 28 can be determined by contacting the common boucon lever 24. When the engine is started, the rotation of the start lever 28 in the fuel increasing direction is controlled by the bush 56. With the regulation by 56, an appropriate injection amount Q2 required at the time of starting can be ensured, and during the start, a fuel injection amount corresponding to an increase in the boost pressure can be ensured. In this case, since the injection amount at the time of starting can be adjusted by selecting the diameter of the bush 56, the amount of rotation of the start lever 28 in the fuel increasing direction can be adjusted strictly even if there is a manufacturing error or an assembly error of each part. Can be controlled.

In this embodiment, the regulating member is constituted by a bush 56 externally fitted to the second shaft 37, and the bush 56 is brought into contact with the boocon lever 24 to thereby turn the start lever 28 at the time of starting. Although the amount of movement is regulated, the regulating member is not limited to this, and may be a projection or the like provided integrally with the start lever 28.

Further, in the conventional boucon lever,
For example, as disclosed in Japanese Patent Application Laid-Open No. Sho 59-101552, the configuration is such that the shaft is simply suspended from the shaft M4 of the boucon lever and hits the back surface of the tension lever 27.
Although the contact portion could not be made much lower due to the assembling of the start lever 28 and the like, according to the present invention, the contact portion 55 projecting from the side by bending the lower end portion of the boocon lever 24 is formed. The bulging portion 3 of the tension lever 27
8 and the bush 56 can be brought into contact with each other, so that the contact position can be shifted downward to increase the distance between the boucon lever 24 and the shaft M4, thereby increasing the injection amount with a small stroke of the boucon lever 24. Can be changed.

Further, in the conventional boucon lever which simply hangs down from the rotation shaft M4, it is necessary to shift the contact position between the tension lever 27 and the boucon lever 24 from the mounting position of the governor spring. When the contact position is, for example, on the upper right side in FIG. 4, the governor spring 35 must be attached to the upper left side. For this reason, in the conventional configuration, it is necessary to selectively use the boucon lever that contacts the right side and the boucon lever that contacts the left side depending on the mounting position of the control lever 34. On the other hand, according to the present invention, since the lower end of the boucon lever 34 is bent to the side, there is no need to use the boucon lever 24 regardless of where the governor spring 35 is mounted. Can be used.

[0032]

As described above, in the present invention, the start lever and the tension lever are integrally rotated during the operation of the engine, and the tension is increased when the boocon lever is rotated to the side that increases the fuel. While increasing the amount of rotation of the lever to obtain a fuel injection amount commensurate with the increase in boost pressure, in the initial stage of starting the engine, the independent rotation of the start lever is adjusted by the adjustment provided on the second shaft of the start lever .
The fuel injection amount at start-up can be suppressed by regulating with the joint assisting member , and the fuel injection amount at start-up can be sufficiently increased while maintaining the appropriate fuel injection amount at start-up. Thus, an injection quantity characteristic that can be obtained is obtained.

[0033] In addition, an adjustment auxiliary provided on the second shaft is provided.
The size and shape of the auxiliary member can be arbitrarily changed.
Can cause manufacturing errors and assembly errors for each part.
As a result, when the fuel injection amount at the start varies
Also depends on the selection of the adjustment auxiliary member. Tweak this
Becomes possible.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a main part of a fuel injection pump according to the present invention.

FIG. 2 is a view showing a boucon lever and a governor mechanism in an initial state used in the fuel injection pump shown in FIG. 1 and in which a collector lever is cut off.

FIG. 3 is a view showing a boucon lever and a governor mechanism in an initial state used in the fuel injection pump of FIG. 1, in which a collector lever and a tension lever are cut off.

FIG. 4 is a view of a boucon lever and a governor mechanism used in the fuel injection pump of FIG. 1 as viewed from a governor sleeve side.

FIG. 5 is an exploded perspective view showing each member of the governor mechanism.

FIG. 6 is a view showing a boocon lever and a governor mechanism used in the fuel injection pump shown in FIG. 1 during startup, with a collector lever cut off.

FIG. 7 is a diagram showing a characteristic of a fuel injection amount with respect to an engine speed of a fuel injection pump in the present invention.

[Explanation of symbols]

 15 Boost compensator 24 Boucon lever 25 Governor mechanism 27 Tension lever 28 Start lever 56 Bush

Claims (1)

(57) [Scope of request for utility model registration] 1. A boost compensator having a boocon lever that rotates to increase fuel in response to an increase in boost pressure, and rotation to a side that increases fuel is restricted by contact with the boocon lever. Tension lever,
A governor having a start lever that rotates integrally with the tension lever during operation of the engine, and independently rotates toward the fuel increasing side in the initial stage of the engine startup, thereby increasing the fuel injection amount in the initial stage of the engine startup. A fuel control mechanism with a boost compensator for a fuel injection pump comprising a mechanism, wherein the tension lever and the start lever are rotatably supported on a first shaft as a support shaft, and the start lever is provided with the first shaft. A second shaft having a different axis is provided, and the peripheral surface of the second shaft is brought into contact with the boocon lever at the initial stage of starting the engine, thereby restricting the amount of rotation of the start lever toward the fuel increasing side. A fuel control mechanism with a boost compensator for a fuel injection pump, wherein an adjustment assisting member is mounted .