JPH08128335A - Governor of fuel injection pump - Google Patents

Abstract

PURPOSE: To prevent generation of smoke at normal temperature time, and enhance startability at low temperature time by adjusting a control rack position at normal temperature starting time in a position of a cancel lever to restrict a rotary range of a stop lever, and adjusting it by a rack limit stopper at low temperature starting time. CONSTITUTION: A stop lever 21 is arranged on a rotary shaft 22 connected to a control rack in a housing 30 of a governor, and is constituted so as to forcedly return the control rack in the uninjected direction regardless of a position of a control lever 13 when this stop lever 21 is operated to a stop position. A cancel lever 26 is arranged so as to come into contact with the stop lever 21, and a control rack position at normal temperature starting time is made movable and startable in a range where the stop lever 21 comes into contact with the cancel lever 26. The control rack position at low temperature starting time is constituted so as to move in a range where the stop lever 21 comes into contact with a rack limit stopper 31.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mechanical governor for a fuel injection pump, and more particularly to an all speed governor capable of optimally changing a starting injection amount and the like by adjusting a movable range of a control rack position.

[0002]

2. Description of the Related Art In starting acceleration or acceleration from a low speed, there is a concern that the maximum injection amount (full Q) will be reached even if the accelerator pedal depression amount is small, smoke will occur frequently, and fuel efficiency will deteriorate. In order to do that,
The device shown in Japanese Patent Publication No. 35 is considered.

This is provided with a cam mechanism for displacing a fulcrum that determines the injection amount characteristic in a link lever device of a governor of a VE type injection pump, and this cam mechanism is interlocked with an accelerator to displace the fulcrum in a fuel increasing direction at low temperature. It was made to let. More specifically, as shown in FIGS. 2 to 4 of the publication, a full load cam 30 is provided between a contact lever 21 of a link lever device 19 and a pump housing 31. By rotating the load cam 30, the contact lever 21 is forcibly separated from the load adjustment screw 26 to increase the starting injection amount, and at normal temperature, the contact lever 21 and the load adjustment screw 26 are brought into contact with each other to increase the starting injection amount. It is designed to be small.

[0004]

As described above, at room temperature starting with a small amount of depression of the accelerator pedal, unlike at low temperature where the injection amount is increased in order to secure good startability, smoke reduction and fuel consumption are reduced. It is required to separately set an optimum starting injection amount (starting Q) from the viewpoint of improving

In order to obtain such starting characteristics with the RSV type mechanical governor with a stop lever, the above-mentioned V
Achieving this with a configuration different from that of the E-type injection pump simplifies the manufacturing process. That is, in the conventional configuration, a cam that can come into contact with the collector lever is joined to the end of the cam shaft 32 provided with the lever 50, and the tip of the lever is connected with the control lever 20 and the rod 56. When the lever 50 is rotated toward the high load side, the lever is rotated and the cam is rotated accordingly to separate the contact lever from the load adjusting screw 26. , It is necessary to secure space inside that much,
If so, the internal mechanism of the governor needs a design change. Therefore, it is desirable that the external structure can be easily changed.

In addition to this, at normal temperature, if it is possible to suppress the injection amount at the time of starting and to have a positive Angleich characteristic that gradually increases the injection amount as the engine speed increases, smoke will be generated. It is desirable because it can be further suppressed.

Therefore, in the present invention, in the RSV type mechanical governor with a stop lever, it is possible to provide the optimum starting injection amount (starting Q) at low temperature and at normal temperature without modifying the internal structure. An object is to provide a governor for a fuel injection pump. Another object of the present invention is to provide a governor that can have a plus Angleich characteristic in the governor characteristic at room temperature.

[0008]

SUMMARY OF THE INVENTION The governor of the fuel injection pump according to the present invention is provided with a cancel lever which can be brought into contact with a stop lever for returning the control rack position to the stop position, and has a control lever for starting at room temperature. The rack position is made to correspond to the idle position of the stop lever, the control rack position at low temperature start is made to correspond to the full Q position of the stop lever, and the idle position is determined by the position where the stop lever contacts the cancel lever. However, the full Q position is determined by the position where the stop lever contacts the rack limit stopper (claim 1).

Here, a cancel lever is rotatably provided on the rotary shaft of the stop lever so that the control rack position at the time of normal temperature start is brought into contact with the cancel lever and the control rack position at the time of low temperature start. Is preferably located at a position where the stop lever contacts the rack limit stopper (claim 2).

Further, a cancel lever is connected to the control lever to synchronize the position of the cancel lever with the position of the control lever (claim 3), and the idle position of the stop lever is released by the rotation of the cancel lever. It is advisable to adopt a configuration (claim 4).

[0011]

Therefore, according to the present invention, the control rack position at the normal temperature start is adjusted by the position of the cancel lever that limits the rotation range of the stop lever, and the control rack position at the low temperature start is adjusted by the cancel lever. Since it is adjusted by the limit stopper, at the normal temperature, the cancel lever can supply the optimum injection amount that suppresses the generation of smoke, and at the low temperature, the rack limit stopper supplies the optimum injection amount from the viewpoint of improving the startability. .

Particularly, if the cancel lever is connected to the control lever so that the position of the cancel lever is synchronized with the position of the control lever, the limit amount of the control rack by the stop lever can be changed by the rotation angle of the control lever. Therefore, at normal temperature, it is possible to provide a positive Angleich characteristic that increases the injection amount as the engine speed increases while suppressing the starting injection amount.

[0013]

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

In FIG. 1, an RSV type mechanical governor is provided with a plurality of levers and springs in a housing 30, and a flyweight assembly 2 is provided at an end of a camshaft 1 of an injection pump. A flyweight 3 that opens and closes according to the centrifugal force generated by the rotation of the camshaft 1, and a slider 4 attached to the arm end of the flyweight 3 axially presses the sleeve 5 to shift the shifter connected to the sleeve 5. 6 is displaced in the coaxial direction.

The lower end of the floating lever 7 is rotatably supported with an axis A as a fulcrum, and the middle is connected to a guide lever 8 with an axis B as a fulcrum. A portion of the floating lever 7 closer to the upper end than the axis B is connected to the control rack 10 via a link 9, and
A start spring 11 for pressing the control rack 10 in the fuel increasing direction is hooked on the upper end portion.

The upper end of the guide lever 8 is rotatably supported on the shaft C together with the upper end of the tension lever 12, and the lower end is connected to the shifter 6 of the flyweight assembly 2.

The movement of the accelerator pedal is converted into the rotation of a control lever 13 described below, which is supported by the shaft D,
The movement of the control lever 13 is transmitted to the swivel lever 14 which rotates about the axis D. A governor spring 15 is hung between the tip E of the swivel lever 14 and the intermediate portion F of the tension lever 12, and the shaft D and the intermediate portion F of the tension lever 12 are different from the tip E of the swivel lever 14. It has an eccentric positional relationship.

However, when the rotation angle of the control lever 13 changes, the tension of the governor spring 15 changes. For example, if the accelerator pedal is depressed and the control lever 13 is rotated toward the β position shown by the solid line, the governor spring 15 changes. 15, the tension lever 12 rotates about the shaft C as a fulcrum and contacts the full load stopper bolt 16 for adjusting the full load position.

Reference numeral 17 is an Angleich spring for correcting the injection amount so as to be proportional to the intake air amount, 18 is an idling spring for maintaining a stable idling operation, and 19 is a stopper for setting the stop position of the control lever 13. It is a bolt.

Further, the governor has a supporting lever 23 fixed to a rotary shaft 22 of a stop lever described below, and this supporting lever 23 engages with a locking piece 24 fixed to the control rack 10. When the stop lever is operated to the stop position regardless of the position of the control lever 13, the control rack 10 forcibly does not inject fuel through the supporting lever 23 and the locking piece 24. It is turned back and the engine is stopped.

The control lever 13 is shown in FIGS.
As shown in FIG. 2, the housing 30 is actually provided on the outer side surface of the housing 30, the middle portion is pivotally supported by the shaft D, the movement of the accelerator pedal is transmitted to the lower end portion, and the upper end portion is connected via the rod 25. Is connected to the lower end of the cancel lever 26.

The connection between the control lever 13 and the cancel lever 26 will be described in more detail. As shown in FIG. 5, the cancel lever 26 slides on a shaft 22 having a stop lever 21 mounted thereon via a cylindrical intermediate member 27. A pin 28 provided movably on the lower end of the cancel lever 26 is provided at one end of the rod 25 so as to be rotatable in the direction perpendicular to the axial direction. Also, rod 2
The other end of 5 is attached to a pin 29 rotatably attached to the upper end of the control lever. Therefore, as shown in FIG. 2, when the control lever 13 is rotated in the fuel increasing direction (clockwise in the figure), the cancel lever 26 is in a direction opposite to the control lever rotation direction (counterclockwise in the figure). If the control lever 13 is rotated about the axis D as a fulcrum from, for example, the idling position (α) to the full load position (β), the cancel lever 26 is also moved from the idling position (γ) accordingly. It is designed to be rotated toward the full load position (δ).

Like the cancel lever 26, the stop lever 21 is provided on the outer surface of the housing 30, extends upward along the housing 30, is bent at a right angle away from the housing 30, and extends downward again. It is bent at a right angle to form a generally U-shape, and is stopped by a spring 33 attached to the rotating shaft 22 (shown in FIG. 6 or 7).
It is biased to the side and can rotate from the stop position to the position where it abuts on the rack limit stopper 31 provided on the housing 30.

At the upper end of the cancel lever 26, there is formed a contact piece 32 that can contact one side of the stop lever 21, and this contact piece 32 determines the upper limit of the rack position of the control rack 10. Further, the stop lever 21 can be brought into contact with the rack limit stopper side.

However, if the rotation of the cancel lever 26 is sufficiently large, the stop lever 21 can be rotated until it comes into contact with the rack limit stopper 31, but if the rotation of the cancel lever 26 is small, the stop lever 2 can be rotated.
1 is rotated only within a range until it comes into contact with the contact piece 32.

Next, the operation of the governor according to the present invention having the above structure will be described. First, to explain the outline of general operation, fully depress the accelerator when starting the engine,
Set the control lever 13 to the full load position (see FIGS. 1 and 2).
(Β position), the swivel lever 14 extends the governor spring 15 and the tension lever 12 is pulled until it comes into contact with the full load stopper bolt 16.
In this state, since the fly weight is closed, the floating lever 7 is pulled by the start spring 11, and the shifter 6 is moved in the direction away from the tension lever 12 (right side in FIG. 1) to be connected to the floating lever 7. The control rack 10 being moved is moved in the fuel increasing direction to set the rack position to the maximum position. As a result, the engine can be started easily. Then, when the engine is started, the flyweight 3 rotates and centrifugal force is generated, and the flyweight 3 is returned until the shifter 6 contacts the tension lever 12.

After that, when the control lever 13 is returned to the idle position (the α position in FIGS. 1 and 2), the tension for pulling the tension lever 12 is removed by the governor spring 15, and the tension lever 12 is spread by the flyweight 3 so that the tension lever 12 moves. It is pushed by and comes into contact with the idling spring 18. As a result, the floating lever 7 rotates about the axis A as a fulcrum to the tension lever side,
The control rack 10 is moved to an idle position where the injection amount is small, and a stable idling operation is maintained at a position where the centrifugal force by the flyweight 3 and the spring force of the idling spring 18 are balanced.

By the way, with the control lever 13 in the full load position, the engine speed increases and the centrifugal force of the flyweight 3 causes the Angreich spring 17 to rotate.
When the force becomes larger than the setting force of No. 1, the Angleich spring 17 starts to contract, the control rack 10 moves in the fuel reducing direction accordingly, and the fuel injection amount decreases by the Angleich stroke. Then, when the centrifugal force of the flyweight 3 and the tension of the governor spring 15 at this time are balanced, the full load maximum rotation speed is maintained.

When the engine speed further rises above the full load maximum speed, the centrifugal force of the flyweight 3 increases,
When the tension lever 12 is pushed against the spring force of the governor spring 15, the control rack 10 moves in the injection amount decreasing direction and stabilizes at a position where the injection amount required for the maximum unloaded engine speed is maintained.

Then, when the control lever 13 is returned to the stop position (ε position in FIG. 1), the swivel lever 14 rotates in the direction in which the tension of the governor spring 15 is removed, and the guide lever 8 is directly pressed to move the flow. The ching lever 7 is rotated to the tension lever side to move the control rack 10 to the non-injection position and stop the engine.

When the stop lever 21 is operated to the stop position regardless of the position of the control lever 13, the supporting lever 23, which is in contact with the locking piece 24, rotates accordingly and the control is performed. Rack 10
Is forcibly returned to the non-injection direction and the engine is stopped.

In contrast to such a basic operation, according to the present invention, as long as the rotation of the control lever 13 is small (while the control lever 13 is set to the idling position), as shown in FIG. Further, the rotation of the cancel lever 26 is small, and the stop lever 21 rotates in the range from the stop position to the contact with the contact piece 32 of the cancel lever 26, and prevents the stop lever from rotating further. . That is, the rotation of the stop lever 21 is restricted before coming into contact with the rack limit stopper 31.

Therefore, at room temperature, even if the accelerator pedal is reduced and the control lever 13 is set to the idle position, the engine can be started easily. Since it is limited to a position smaller than the full rack position (a rack position where an optimum starting injection amount is obtained at normal temperature shown by A in FIG. 8), excessive fuel is not injected and smoke is suppressed. It is possible to improve fuel efficiency.

On the other hand, when the rotation of the control lever 13 increases, the stop lever 21 contacts the rack limit stopper 31 and does not rotate further, as shown in FIG. When the engine is started at a low temperature, the control lever 13 is moved to the full load position by depressing the accelerator greatly in order to improve the startability. In this state, the stop lever 21 is exactly in contact with the rack limit stopper 31. The rack position is set to the same level as the conventional full rack position (shown by B in FIG. 8).

If the rack limit stopper 31 is not provided, the maximum rack position at low temperature start is determined by the contact of the cancel lever 26 with the contact piece 32, as shown by the broken line in FIG. Since the limit stopper 31 functions as a limiter that determines the upper limit of the rack position, the rack position is set by adjusting the rack limit stopper 31 to obtain an optimum starting injection amount that is sufficient even at low temperatures.

Further, a point to be noted in the present invention is that
When the rotation amount of the control lever 13 is gradually increased from the idle position (the engine rotation speed is gradually increased), the rotation amount of the cancel lever 26 is gradually increased and the rotation range of the stop lever 21 is increased. Since the movable range of the control rack 10 can be gradually increased, it is possible to obtain the RSV type governor having the plus Angleich characteristic at normal temperature as shown by the chain double-dashed line in FIG. Therefore, at room temperature, it is possible to eliminate the generation of smoke in the shaded area.

[0037]

As described above, according to the present invention,
The limit amount of the control rack by the stop lever is determined by the cancel lever at normal temperature and by the rack limit stopper at low temperature, so fuel consumption and smoke are reduced at the start at normal temperature. From the viewpoint, the injection amount can be suppressed more than at low temperature, and at low temperature, the injection amount can be increased from the viewpoint of improving startability, and the optimum injection amount required in each environment can be set.

In particular, if the limit amount of the control rack by the stop lever can be determined by the cancel lever which is interlocked with the control lever, the rotation range of the stop lever can be changed depending on the position of the control lever. It is possible to provide a Plus Angle characteristic in which the limit amount of the control rack is gradually increased with an increase in the, and it is possible to obtain a performance equivalent to that of a governor having such a characteristic.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing a governor mechanism of a fuel injection pump according to the present invention.

FIG. 2 is a side view of the governor of the fuel injection pump according to the present invention as viewed from the outside.

FIG. 3 is a partially cutaway view of the governor of FIG. 2 as viewed from the left side.

FIG. 4 is a perspective view showing the periphery of a control lever, a cancel lever, and a stop lever.

FIG. 5 is a diagram showing a link structure between a control lever and a cancel lever.

FIG. 6 is a diagram showing a relationship between a cancel lever and a stop lever when a control lever is at an idling position.

FIG. 7 is a diagram showing the relationship between the cancel lever and the stop lever when the control lever is at the full load position.

FIG. 8 is a diagram showing a performance diagram of the governor according to the present invention.

[Explanation of symbols]

 10 Control Rack 13 Control Lever 21 Stop Lever 26 Cancel Lever 31 Rack Limit Stopper

Claims (4)

[Claims] 1. An all-speed governor of a fuel injection pump having a stop lever for returning a control rack position to a stop position, wherein a cancel lever capable of contacting the stop lever is provided, and the control rack position at the normal temperature start is stopped by the stop lever. The control rack position at low temperature start is made to correspond to the full Q position of the stop lever, and the idle position is determined by the position where the stop lever contacts the cancel lever. A governor for a fuel injection pump, the position of which is determined by the position where the stop lever contacts the rack limit stopper. 2. The cancel lever is rotatably provided on a rotation shaft of the stop lever, and makes a control rack position at a normal temperature start correspond to a position at which the stop lever comes into contact with the cancel lever.
The governor for a fuel injection pump according to claim 1, wherein the control rack position at the time of cold start corresponds to the position where the stop lever contacts the rack limit stopper. 3. The governor for a fuel injection pump according to claim 1, wherein the cancel lever is connected to the control lever so that the position of the cancel lever is synchronized with the position of the control lever. 4. The governor for a fuel injection pump according to claim 1, wherein the idle position of the stop lever is released by rotating the cancel lever.