JP2513633B2 - Governor for fuel injection pump - Google Patents

Description

TECHNICAL FIELD The present invention relates to a governor for a fuel injection pump,
It has at least one control lever pivotable about an axis for controlling the amount of fuel injection injected for each stroke of the injection pump piston by a force corresponding to the number of revolutions. Force acting at least indirectly against the force of the adjusting spring device, which is connected to the control lever on the one hand and operatively connected to the adjustable first support on the other hand, at least indirectly. In addition, an adjusting spring, which is auxiliary connected to the control lever, is provided, and the adjusting spring is fixed to an adjustable second supporting portion, and the adjusting spring is fixed to the second supporting portion. Of the type in which the angular position of the axis of the auxiliary adjusting spring can be changed with respect to the catching point of the adjusting spring.

2. Description of the Related Art In a speed governor of the type known from German Utility Model Registration No. 1784561, a fuel injection pump is provided with a centrifugal speed governor via a two-armed lever to control a supply amount. Has a control rod connected to. One side of the adjusting sleeve of the centrifugal governor is loaded by means of an adjusting spring, the preload of which is adjustable by means of a lever used as a first support. Furthermore, an auxiliary spring acts on the control rod, the other end of this auxiliary spring being used as a second supporting part, which can be swung by means of an adjusting lever about an axis fixed to the casing. It is fixed to the end of. The auxiliary spring is adjustable with respect to its direction of action by means of a swivel arm, acts in the basic position to assist the adjusting spring and is aligned substantially axially parallel to the adjusting spring. By changing the angular position of the axis of the auxiliary spring with respect to the adjusting rod, the component force acting in the direction of the adjusting rod is changed, which results in a change in the overall spring characteristics of the adjusting spring and the auxiliary spring. To be

The problem to be solved by the invention.However, in the case of such a type, since the rotation axis of the swing lever is slightly deviated from the fixing point of the auxiliary spring in the control rod, when the angular position of the auxiliary spring changes, the auxiliary position of the auxiliary spring changes. The spring preload changes little. Also, there is no provision for separately changing the preload of the auxiliary spring. Such a device affects the governor's reduction control but requires additional structural space due to the movement of the swivel arm. In addition, the control lever must be precisely adjusted and the control lever must be provided with an adjusting and fixing device.

Means for Solving the Problems According to the present invention for solving the above problems, the second support portion is adjusted along a straight line extending in a plane perpendicular to the direction in which the axis of the control lever extends. It has become.

Action According to the configuration of the present invention, the angular position of the axis of the auxiliary adjusting spring and at the same time the preload of the auxiliary adjusting spring can be controlled by sliding the support portion linearly, and thus the reduction control can be performed. The gradient or decrease control characteristic (P-degree) and the decrease control rotation speed can be easily adjusted at one place of the fuel injection pump. The speed governor according to the invention is also advantageous in that it is inexpensive, saves space and can be installed in a dispensing injection pump of particularly small construction. In particular, a fuel pump with a speed governor according to the present invention is suitable for use in an internal combustion engine, for example, which must maintain an accurate speed with a precisely defined reduction control characteristic (P-degree) when a current is generated. Is suitable.

Embodiment According to the embodiment described in claim 2,
The threaded bolt provides a very finely tuned adjustment without the need for a significant increase in the structural space of the fuel injection pump. Both the angular position adjustment and the preload adjustment are obtained by means of a rotating and adjusting movement, which offers advantages in connection with the operation. Furthermore, according to the embodiment as claimed in claim 3, the preload of the auxiliary adjusting spring can be changed not only by changing the turning position but also by adjusting the eccentric position of the supporting portion. According to the embodiments of claims 4 and 5, the preload of the spring can be varied in a simple manner and with a large adjustment range, as in the embodiment of claim 2. A stable suspension format is obtained that offers similar advantages.

Example Next, the configuration of the present invention will be specifically described with reference to the example shown in the drawings.

FIG. 1 shows a part of a known distributed fuel injection pump with a pump piston. This pump piston 1 is replaced by a reciprocating movement and at the same time a rotary movement by means not shown in the drawing and is guided in a bush 3 which is incorporated in the casing 2 of the fuel injection pump. The casing forms the pump suction chamber 4,
The pump suction chamber 4 is filled with fuel. The pump suction chamber 4 is normally maintained at a pressure controlled according to the number of revolutions in order to perform a control action. A ring slider 6 is arranged on the pump piston as a fuel amount control mechanism, and the ring slider 6 controls an opening of a load reducing conduit 7 leading from a pump working chamber (not shown) in the pump suction chamber 4. For this reason, the ring slider 6 can be moved along the pump piston. In the illustrated embodiment, the amount of fuel injected by receiving the high pressure of the pump piston in each pump stroke causes the ring slider 6 to pump. The more it moves toward the top dead center of the piston 1, the more it becomes.

A speed governor is provided to control the ring slider 6. This speed governor has a control lever 9, which is pivotable about a shaft 10 which is fixed in the casing but which is adjustable and whose one end is connected via a head 11. The ring slider 6 is connected to and controls the ring slider 6. The control lever is basically provided as a single control lever, but in the embodiment shown the control lever arrangement is provided with multiple levers. This control lever 9 is a starter lever which is directly loaded by the adjusting sleeve 13 of the centrifugal speed governor 8, which is only shown in part in the drawing. The shaft 10 of the control lever 9 is further provided with a one-armed pulling lever 14 (control lever). At the outermost end of the pulling lever 14, one end of the adjusting spring device 15 is connected to the coupling head 16. Is acting through. The other end of the adjusting spring device 15 is fixed to the lever arm 18. The lever arm 18 is mounted on a shaft 19 guided through the pump casing 2 and an adjusting lever 20 is fixed to the outermost end of the shaft 19. By means of this adjusting lever 20, the spring force of the adjusting spring device is adjusted in a known manner. This adjusting spring device acts against the force effect of the adjusting sleeve 13. The control lever 9 is brought into contact with the tension lever 14 under the action of the adjustment force according to the rotation speed of the adjustment sleeve 13. A leaf spring as a starter spring 17 is arranged between the starter lever (control lever 9) and the tension lever 14, and this leaf spring is compressed in the process in which the control lever 9 is brought into contact with the tension lever 14. Be punished. As soon as the force action of the adjusting sleeve 13 overcomes the force of one of the starter spring 17 or the spring of the adjusting spring device 15, the starter lever (control lever 9) or this starter lever and the pulling lever 14
Are swung together, and the ring slider 6 is displaced to a position where a small amount of fuel is injected. This reduction control process is performed more rapidly the softer the spring characteristic is at a given preload.

In order to carry out no-load operation control, a head 16 located on the other side of the adjusting spring device 15 of the tension lever 14 is further provided.
An unloaded spring is arranged between the tension lever 14 and the tension lever 14. This no-load spring, during the reduction control process of the low load range,
The head 16 contacts the tension lever 14 and the adjusting spring device 15
Is first compressed until it is loaded independently of the adjustment force of the adjustment sleeve 13.

A common shaft 10 for the starter lever and the pulling lever is carried by an adjusting lever 23 which is pivotable under spring force around a casing fixing point (not shown) for adjustment. The adjustment is carried out by means of a screw 24 which is screwed into the wall of the casing 2 and which acts on the adjusting lever 23. With respect to this adjusting process, the illustrated pump is the same as a distributed type injection pump of a general structure, but in the illustrated pump, the tension lever 14 is provided with an adjusting spring device 15 at an outer end portion of the tension lever 14. It has an arm 25 extending obliquely downward from the hooking point. One end of an additional (auxiliary) adjusting spring 26 is fixed to the end of the arm 25, and the other end of the adjusting spring 26 is hooked on the support 27. The adjusting spring 26 is designed as a tension spring and acts against the spring force of the adjusting spring device 15. The support 27 has the shape of a constricted roller and is attached to the end of a threaded bolt 29. The threaded bolt 29 is screwed into the wall of the casing 2 and has, on the outer end, a form-fitting surface 30 for rotation and a counternut 31 for fixing in position. The axis of the threaded bolt 29 is the auxiliary adjustment spring 26 of the arm 25.
The hooking point 32 of the is present in the pivot plane drawn when the tension lever 14 is displaced. The axis of the threaded bolt 29 extends substantially parallel to the output position of the tension lever 14 or the control lever 9.

The illustrated speed governor is an all-speed speed governor, and the rotation speed is adjusted by adjusting the load of the adjusting spring device 15. When the number of rotations is exceeded, the tension lever 14 is displaced together with the control lever 9 and the ring slider 6
Is shifted downward. A small amount of fuel is injected at this position on the ring slider. As a result, the rotational speed is reduced again. As a result, the adjustment force applied to the adjustment sleeve 13 again decreases, so that the tension lever
14 again occupies the swivel position, which corresponds to a higher fuel injection quantity. This control process is performed at a low rotation speed or a high rotation speed depending on the magnitude of the load. Adjustment lever at this time
The load at 20 is adjusted and, if appropriate, means (not shown in detail) are fixed to this adjusting lever 20.

According to the governor shown, the reduction control gradient or the reduction control speed can be additionally changed. That is, the gradient of the fuel injection amount characteristic curve between the full load operation and the no load operation can be changed. For this purpose, an additional adjusting spring 26 is provided and the support 27 of this adjusting spring 26 is movable. By moving the support 27 in the axial direction of the threaded bolt 29, an additional adjusting spring 26
The axial position of can be changed. By extending the axis of the additional adjusting spring 26 each time and lowering the vertical line from this adjusting spring 26 to the axis 10 of the tensioning lever 14, the preload of the additional adjusting spring 26 responds to the reduction control. The adjustment spring 26 increases as the displacement increases.
It can be seen that the effective lever arm length exerted by the force is reduced relative to axis 10. By displacing the support 27 in this manner, the effective spring characteristic exhibited by the gradient of the reduction control process is changed when a regulated speed is obtained. By shifting the angular position of the additional adjusting spring 26, which is possible in the embodiment shown, the desired reduction control gradient (P-degree) can be adjusted very accurately. At this time, the axis of the adjusting spring 26 is preferably located in the pivot plane described by the hooking point 32 when the tensioning lever 14 is displaced.

As the support 27 is laterally displaced, the preload of the additional adjusting spring also changes. This is advantageous in order to obtain a predetermined reduction control characteristic curve in specific cases. However, in the variant embodiment shown in FIG. 2, the preload itself is, as shown in FIG.
However, it can be further changed if it has a hooking point 34 that is eccentrically positioned with respect to the axis of the threaded bolt 35. When the threaded bolt 35 is rotated, the hooking point 34 draws an arc. Over the radius or diameter of this arc, the end of the additional adjusting spring 26, which is hooked at this hooking point 34, is stretched for one stroke only, which allows the adjusting spring to be preloaded. Can be changed accordingly. If the thread of the threaded bolt 29 is very fine, the angular position adjustment obtained at this time when adjusting the stroke does not significantly affect the adjustment result.

In FIG. 3 as a modification of the embodiment of FIG. 1, one end of an additional adjusting spring 26 'is hooked directly into a hole 37 provided at the end of the tensioning lever 14, A governor of the type shown in which the other end of a typical tension spring 26 'is hooked on a support 27' at the end of a threaded bolt 29 'is shown. Unlike the embodiment of FIG. 1, the threaded bolt has a tension lever 14 on the same side as the side on which the lever arm 18 on which the adjusting spring device 15 is hooked is provided.
Are located in That is, the spring force action of the additional adjusting spring 26 'assists the adjusting spring device 15. Such a configuration is necessary to obtain a predetermined adjustment characteristic for each individual case. The adjustability of the angular position of the additional adjusting spring and its preload takes place in the same manner as in the embodiment of FIGS. 1 and 2.

In the embodiment of FIG. 4, an additional adjusting spring 26 or 2
Another possibility for changing the angular position of the 6'axis has been shown. At the same hooking point of the tensioning lever 14 as in the embodiment of FIG. 1 or 3, the other end of the adjusting spring 26 is fixed to a support 39 configured as a slide member. There is. The support 39 has a notch on the inside.
It is provided with 42 and has a substantially rectangular shape elongated in the sliding direction. The elongated cutout 42 has a shape-connecting surface, for example, a tooth row, on one side 43. A corresponding pinion 46 engages with this row of teeth. The pinion 46 has the same thickness as the slide member (support portion 39) as can be seen in FIG. The pinion is the casing 2 of the fuel injection pump.
It is mounted on a shaft 48 which is guided through it and which is externally rotated and fixed by a suitable device. Pinion 46
A head disc 50 is integrally formed on the opposite side of the head disc 50.The head disc 50 exceeds the width of the notch 42, and a slide member is provided between the head disc and the parallel wall portion of the casing. To guide. Support 39 opposite the additional adjusting spring 26
The outer side surface side of the (slide member) extends straight and abuts a corresponding linear slide surface 52 provided inside the pump casing. When the pinion 46 is rotated, the pinion 46 engages with the shape connecting surface 45 (tooth row) and slides the slide member 39 along the slide surface 52. With this device, a stable suspension of the shape for the additional adjusting spring 26 or 26 'is obtained. Also, since such a structure requires only a small space in the fuel injection pump, the device can be assembled in a very small size, and the P-type fuel injection pump can be assembled without changing the casing shape of a conventional distributed fuel injection pump. Can affect the degree. Many adjustability are provided due to the different reduced control properties.

Effects As described above, according to the present invention, it is possible to control the angular position of the axis of the auxiliary (additional) adjusting spring and simultaneously control the preload of the auxiliary adjusting spring, and thus the reduction control gradient or the characteristic and the reduction control rotation. The number and can be easily adjusted at one place in the fuel injection pump. Furthermore, the speed governor according to the invention is inexpensive and space-saving and is particularly suitable for dispensing pumps of small construction.

[Brief description of drawings]

FIG. 1 is a partial sectional view of a distribution type fuel injection pump incorporating a main part of a speed governor according to a first embodiment of the present invention, and FIG. 2 is a modification of a supporting portion according to the embodiment of FIG. FIG. 3 is a partial side view showing an example, FIG. 3 is a partial sectional view of a distribution type fuel injection pump having a governor according to the second embodiment, and FIG. FIG. 5 is a partial sectional view of the supporting part according to FIG. 1 ... Pump piston, 2 ... Casing, 3 ... Bush, 4 ... Pump suction chamber, 6 ... Ring slider, 7 ...
… Load-reducing conduit, 8 …… Centrifuge, 9 …… Control lever, 10 …… Axis, 11 …… Head, 13 …… Adjustment sleeve, 14
...... Pulling lever, 15 …… Adjusting spring device, 16 …… Coupling head, 17 …… Starter spring, 18 …… Lever arm, 19 …… Axis, 20 …… Adjusting lever, 23 …… Adjusting lever, 24 …… screw, 25 …… arm, 26,26 ′ …… adjusting spring, 27,27 ′ …… supporting part, 29,29 ′ …… threaded bolt,
30 …… Shape connecting surface, 31 …… Balanced nut, 32,34 ……
Hooking point, 35 …… Screwed bolt, 36 …… Adjusting spring, 37 …… Hole, 39 …… Support part, 42 …… Notch, 43 ……
Side side, 45 …… Shape connection surface, 46 …… Pinion, 48 ……
Axis, 50 …… Head disk, 51 …… Side side, 52 …… Sliding surface,

Claims (1)

(57) [Claims] 1. A governor for a fuel injection pump, comprising:
It has at least one control lever (9, 14) which can be swiveled about an axis (10) for controlling the fuel injection amount injected at each injection pump piston stroke by a force according to the rotational speed. The force corresponding to the number of rotations is
The control lever (9) is at least indirectly resisted against the force of an adjusting spring device (15) which is connected on the one hand to the control lever (14) and on the other hand is operatively connected to an adjustable first support part. Is provided with an adjusting spring (26, 26 ') auxiliary connected to the control lever (14), and the adjusting spring can adjust the second support portion (27). , 27 ', 39), said auxiliary adjustment spring (26, 2) being fixed by said second support.
6 ') of the type in which the angular position of the axis can be changed with respect to the hooking point (32) of the adjusting spring, the second support portion (27, 27', 39) is A speed governor for a fuel injection pump, which is adapted to be adjusted along a straight line extending in a plane perpendicular to a direction in which an axis (10) of (9) extends.