JP2594795Y2 - Flow control device for fuel injection pump - Google Patents

Description

[Detailed description of the invention]

[0001]

In the present invention, a flow control device provided with a control lever is provided on a pump casing, and the flow control device operates a flow control mechanism for determining the start and end of supply of the injection pump. It relates to a flow control device for a fuel injection pump of an internal combustion engine, which can be moved by mechanical transmission of the movement of another lever.

[0002]

2. Description of the Related Art The structure and operation of fuel injection pumps for internal combustion engines, especially diesel engines, are known. In this case, the injection time and the injection amount are adjusted. The injection amount is changed by a so-called flow control device. For example, Robert
A fuel injection pump with a flow control device which is operated mechanically by means of a printed matter from t Bosch GmbH (distribution injection pump, VE, VDT-D 5/2 De (3.81). Is adjusted by sliding an annular slider over the pump plunger, the pump plunger being provided with a discharge passage which is covered by the annular slide and is openable. Is controlled via a lever mechanism.In order to achieve the highest accuracy and to avoid instability, the lever mechanism is provided with a spring, which is arranged so that the lever mechanism is in front of it. ,
For example, when no electric or pneumatic force is applied from the accelerator pedal, the annular slider automatically returns to the basic position. In the case of a lack of energy, that is to say especially when the accelerator pedal movement is not transmitted mechanically, the annular slider automatically reaches a position at which the injection quantity is zero or corresponds to the quantity at idle. Therefore, load operation of the internal combustion engine is no longer possible.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a flow control device for a fuel injection pump having an emergency rotation characteristic.

[0004]

According to the invention, this object is achieved in a flow control device of the kind mentioned at the outset in order to transmit the movement of the other lever to the control lever. Has a cam disk, the range of the cam surface of this cam disk cooperates with the other of the adjusting lever and the other lever, and when the other lever is moved from the zero displacement position to the maximum displacement position, the adjusting lever has a small displacement. A cam surface is formed so as to be able to move from and to the zero displacement position and from this zero displacement position to the maximum displacement position in the opposite direction, the small displacement of the adjusting lever being greater than zero displacement and less than the maximum displacement; The adjusting lever is biased by a spring, which, as soon as the connection between the flow regulating device and the accelerator pedal is interrupted, causes the adjusting lever to assume its small displacement position, Ie is solved by moving the emergency rotational position. By arranging a cam disk with a specially formed cam surface, the adjusting lever and the annular slider are always in the emergency rotation position when the other lever is in the zero displacement position. The annular slider is sequentially movable from this emergency rotation position to the zero feed, idle, full load and start enrichment positions. The lever provided on the inlet side of the fuel injection pump is continuously movable in the same direction.

[0005] Advantageous embodiments of the invention emerge from the claims 2-4. In particular, claim 3 is important. First, the range in which the distance to the rotation point of the cam surface extends
This results in a very rapid movement of the annular slider from the emergency rotation position to the zero supply position and vice versa. The subsequent convex area of the cam surface, which increases the distance to the point of rotation, changes the movement of the annular slider into a substantially linear movement, so that in this range the adjustment of the lever at a given angle is always approximately the same distance. Is the same as sliding. The convex shape of the cam surface is suitably adjustable to obtain different desired angle-displacement-relationships.

[0006]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing a preferred embodiment of the present invention; FIG. 1 is a side view of the flow control device of the present invention, and does not show a pump casing.

Printed material from Robert Bosch GmbH (distribution type injection pump, VE, VDT-D 5/2)
De 3.81) starts with a flow regulator as shown in De 3.81). In a pump casing (not shown), there is provided a flow control mechanism capable of moving on a pump plunger 11, that is, a flow control device 10 having an annular slider 12. The pump plunger 11 has a discharge passage 13. This discharge passage communicates with the bore 14 and can be covered or opened by the annular slider 12 to determine the fuel delivery. When the discharge passage 13 is completely covered, the maximum fuel transfer amount occurs. The movement of the annular slider 12 is performed by an adjusting lever 15. This adjustment lever is moved by a lever mechanism 16.

The adjusting lever 15 is formed in a double arm shape and is rotatably mounted in a lower area (bearing 17). The movement of the adjusting lever 15 on the annular slider 12 is performed by a driver 18 connected to the adjusting lever 15. This driver engages with the recess 19 of the annular slider 12. The lever mechanism 16 is substantially similar to the lever 20.
And a connecting lever 21 pivotally connected to the lever, and a cam disk 23 fixedly connected to the lever 20 via a shaft 22. The shaft 22 extends into the plane of the drawing,
At the same time, the connection between the inside of the pump casing (not shown) and the members (lever 20, connection lever 21) provided outside the pump casing is performed.

In the region of the upper end 24, the adjusting lever 15 is biased by a cam disc 23 via a roller 25 which is rotatably mounted. The cam surface 26 of the cam disk 23 facing the roller 25 has a special shape. The lower surface 27 of the cam surface is formed in a concave shape,
A convex area 28 is connected to the upper side. The transition from the concave area to the convex area extends from the center of the shaft 22 to the cam surface 26.
To the smallest range. The lever 20 and the cam disk 23 rotate around the shaft 22. In order to avoid unspecified lever positions, the lever 20 and the adjusting lever 15 are biased by a tension spring 29 and a spiral spring 30. This spiral spring is provided in the area of the bearing 17.

Next, the course of movement of each component will be described.

The movement of the accelerator pedal (not shown) is transmitted to the connecting lever 21. As a result, this connecting lever moves in the direction of arrow 31 during gas supply. Correspondingly, the lever 20 rotates about the shaft 22 and the cam disk 23 fixedly connected thereto rotates in the direction of arrow 32. The roller 25 is moved from the emergency rotation position shown in FIG.
Move in the direction of. The roller 25 is on the cam surface 26 and the shaft 2
As soon as it has passed the shortest distance to the center of 2, the movement of the adjusting lever 15 takes place in the opposite direction, ie in the direction of the arrow 34. In a range 28 connected to the cam surface 26, the cam surface 26 is formed in a convex shape. The movement of the adjusting lever 15 is transmitted to the annular slider 12 via the entrainer 18 in the recess 19. In response to the two directions of movement of the adjusting lever 15, the annular slider 12 first moves in the direction of arrow 35 and subsequently in the direction of arrow 36. In the illustration, the annular slider 12 does not open the entire cross section of the discharge passage 13. As soon as the connection between the flow control device 10 and the accelerator pedal is interrupted, this emergency rotational position automatically occurs. This is done, for example, when using external energy (electromagnetically, pneumatically, hydraulically) to transmit the accelerator pedal position. With the above structure, the flow control device according to the present invention can guarantee the operation of the vehicle even in the case of a failure. During the course of the above-mentioned movement, the discharge passage 13 is first moved by the annular slider 12 to the zero displacement position (the roller 25 is
From the zero displacement position (idling position), through the full load position and slowly closing again to the starting position (roller 25 is furthest from shaft 22). At this time, the angle drawn by the lever 20 is about 60 °.

The special shape of the cam surface 26 causes a change in the adjustment lever movement relative to the movement of the lever 20. When the roller 25 contacts the convex area of the cam surface 26, the lever 2
0 or the rotational movement of the cam disk 23 is converted to a linear movement. That is, when the change in the angle of the shaft 22 is the same, substantially the same change in displacement of the annular slider 12 occurs. The lower area 27 of the cam disk 23 is formed concave between the idling position and the emergency rotation position. Thereby, only a small rotation angle is required for adjustment in this range.

As in the above embodiment, the roller and the cam disk can be exchanged with each other and arranged on the opposite levers. In addition to the flow regulating device 10, other regulating and compensating devices can be provided as known by the Robert Bosch GmbH print mentioned above.

[0014]

According to the flow control device of the present invention, since the cam disk of the lever mechanism has a cam surface that guarantees the emergency rotation position of the annular slider at the basic position of the lever mechanism, the connection between the fuel injection pump and the accelerator pedal is made. There is an advantage that the load operation can be performed even when is canceled.

[Brief description of the drawings]

FIG. 1 is a side view of the flow control device of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Flow control apparatus 11 Pump plunger 12 Annular slider (flow control mechanism) 13 Discharge passage 14 Internal hole 15 Adjustment lever 16 Lever mechanism 17 Bearing 18 Entrainer 19 Depression 20 Lever 21 Connection lever 22 Shaft 23 Cam disk 24 Upper end 25 Roller 26 Cam Surface 27 Lower concave area 28 Upper convex area 29 Tension spring 30 Spiral spring 31, 32, 33, 34, 35, 36 Arrow

──────────────────────────────────────────────────続 き Continuation of the front page (56) Reference Jikken Sho 43-24641 (JP, Y1) (58) Field surveyed (Int. Cl. ⁶ , DB name) F02D 1/00-1/14

Claims (4)

(57) [Scope of request for utility model registration] 1. A flow control device (10) having a control lever (15) is provided on a pump casing, and the flow control device operates a flow control mechanism (12) for determining start and end of supply of an injection pump. Adjusting lever is other lever (2
0) can be moved by mechanical transmission of movement,
In a flow control device for a fuel injection pump of an internal combustion engine, in order to transmit the movement of another lever (20) to a control lever (15), this control lever (15) and another lever (2) are transmitted.
0) comprises a cam disc (23), the extent of the cam surface (26) of which cooperates with the other of the adjusting lever (15) and the other lever (20), and the other lever (2).
0) is moved from the zero displacement position to the maximum displacement position so that the adjusting lever (15) can move from the small displacement to the zero displacement position and from this zero displacement position to the maximum displacement position in the opposite direction. A surface (26) is formed, wherein the small displacement of the adjusting lever (15) is greater than zero displacement and less than the maximum displacement, and the adjusting lever (15)
Is biased by a spring (30) which, as soon as the connection between the flow regulating device (10) and the accelerator pedal is interrupted, causes the regulating lever (15) to move to its small displacement position, i.e. emergency rotation. A flow control device characterized by moving to a position. 2. A cam disc (23) is mounted rotatably about a shaft (22), the distance between the center of said shaft (22) and the cam surface (26) being the distance of the adjusting lever (15). 2. The flow control device according to claim 1, wherein the emergency rotation position corresponding to the small displacement position becomes shorter from the zero displacement position, and increases from the zero displacement position to the maximum displacement position. 3. The cam surface (26) is formed in a concave shape (27) from the emergency rotation position of the adjusting lever (15) to the zero displacement position, and is convex (28) from this zero displacement position to the maximum displacement position.
3. The flow control device according to claim 2, wherein the flow control device is formed as follows. 4. The cam disc (23) is connected to another lever (2).
4. The flow control according to claim 1, wherein the flow control is fixedly connected to the control lever and cooperates with a roller provided at an end of the control lever. apparatus.