JPS6016749Y2 - Linkage device for fuel pump control - Google Patents

Description

[Detailed Description of the Invention] The present invention is an improvement of an internal combustion engine, in particular, when a fuel pump is driven by a hydraulic governor, a link device with a buffer function is interposed between the fuel pump and the hydraulic governor. (This is intended to improve the stability of fuel pump control and promote miniaturization of the coupling mechanism itself.

In internal combustion engines such as diesel engines, in order to suppress sudden changes in engine speed due to load fluctuations and stably maintain the required engine speed, the engine speed is input and the fuel pump is adjusted accordingly. A governor device is attached to adjust the amount of fuel injection by adjusting the amount of movement of the control rack, but among the governor devices, a hydraulic governor with a built-in hydraulic device is different from a conventional mechanical governor. In comparison, it has various advantages such as being compact despite its large control force, being highly versatile for a wide variety of models, and being able to control with high precision. It has become widely used in generators and other general power engines.

When this type of hydraulic governor is attached to an engine, the terminal lever 2 on the hydraulic governor 1 side and the control rack 4 on the fuel pump 3 side are usually connected by a link 5, as shown in FIG. A compression spring 9 is interposed between the inner wall 7 of the cylinder 6 and the piston 8 in the middle of the link 5 to limit the load at high loads, and an engine stop bundle 10 is installed in the middle of the link system. By tilting the bundle 10 from the outside in the direction of compressing the compression spring 9, that is, in the direction of the arrow X, the control rack 4 of the fuel pump 3 can be moved to the non-injection position.

However, as described above, when the buffer spring 9 built into the cylinder 6 is interposed in the link system connecting the hydraulic governor 1 and the fuel pump 3, the proximity distance between the hydraulic governor 1 and the fuel pump 3 is limited. , not only does the connecting link mechanism between the two become larger, but also a heavy object such as the cylinder 6 that holds the buffer spring 9 must be installed in the link system.
This has a problem in that it adversely affects the movement of the link 5 and makes it difficult to lubricate between the cylinder 6 housing the buffer spring 9 and the piston 8.

This invention focused on the problems that existed in the conventional connection mechanism that connects the hydraulic governor and the fuel injection pump, and was devised to correct and improve the problem. By connecting the two control levers with a special link mechanism and providing a biasing spring in one of the levers constituting the link mechanism, the fuel pump can be controlled smoothly, and the biasing spring can increase the maximum pressure of the fuel pump. The link mechanism is designed to provide buffering during injection.

The specific contents of the present invention will be explained in detail below with reference to embodiments shown in the accompanying drawings.

FIG. 2 is a schematic sectional view showing an example of a fuel pump control mechanism to which the link device of the present invention is applied, and FIG. 3 is a sectional view taken along the line I-I in FIG. 2. In each figure,
11 is a fuel pump; 12 is a link case that is fixed to the side of the fuel pump 11 and houses a link device that is an essential part of the present invention; 13 is a governor drive attached to the other side of the link case 12; The driving device case 13 is a device case, and the drive device case 13 includes a fuel pump camshaft 16 which is rotatably supported by bearings 14 and 15 across the inside of the link case 12 from the bottom of the fuel pump 11, and a tip end of the camshaft 16. The governor drive shaft 19 includes a heavy-duty drive gear 17 fixed to the drive gear 17, and a governor drive shaft 19 with a driven gear 18 fixed to the lower end that meshes with the drive gear 17. 21 rotatably supports the governor drive shaft 19, and the bearing case 2
The input shaft 23 of a known hydraulic governor 22 mounted and fixed on the upper surface of the governor drive shaft 19 is connected at a spline portion 24 formed at the upper end of the governor drive shaft 19.

The hydraulic governor 22 has a terminal that protrudes from the upper side surface according to the rotation speed when the input shaft 23 is rotated by the rotation of the fuel pump camshaft 16 via the gear 17, 18 and the governor drive shaft 19. The shaft 25 rotates in the fuel increasing direction indicated by the arrow (+) or the fuel decreasing direction indicated by the arrow (-), and the terminal lever 2 is fixed thereto.
6 can be tilted.

On the other hand, in the figure, reference numeral 27 denotes a support shaft that is rotatably supported by bearings 28 and 29 at the upper part of the link case 12, and the support shaft 27 is attached to a portion projecting outward from the case 12. Terminal lever 2 on the side of the hydraulic governor 24
6, a control lever 31 connected via a link 30 is fixed, and a pin 32 provided at the lower end of the support shaft 27 extends over the case 12 to secure the intermediate portion of the second lever 34. The second
The lever 34 is fixed.

The second lever 34 has an upper end 34a connected to a rack connecting member 37 fixed to the tip of the control rack 35 of the fuel pump 11 by a bolt 36 via a connecting link 38, and a lower end 34b of the second lever 34. A connecting pin 40 projecting laterally from the boss portion 39 and a sliding tube 41 fitted onto the connecting pin 40 are slidably inserted into a sliding groove 43 provided at the lower end of the third lever 42. There is.

The third lever 42 is fixed to the inner end 45a of a third lever shaft 45 supported by a bearing 44 provided in the link case 12, and the auxiliary lever 46 is fixed to the case outer end 45b of the lever shaft 45. Due to the action of a tension spring 49 stretched between a hook pin 47 provided at the tip and a fixing portion 48 at an appropriate position, it is constantly urged to rotate in the direction of arrow V with a required strength.

Further, 50 is rotatably supported on the side surface of the link case 12 so as to face the third lever shaft 45 by a bearing 51 provided coaxially and symmetrically with the bearing 44 of the third lever. The stop lever 52, which is a stop lever shaft fixed to the inner end 50a of the lever shaft 50, is attached to the link case 1 at one contact surface 52a.
The lower end 34b of the second lever 34 contacts the stopper 53 integrally formed with the second lever 34 at the other contact surface 52b.
A remote control (not shown) is attached to the upper end 54a of the stop bundle 54, which is in contact with the stop bundle 54 to limit the movement of the second lever 34 in the V direction and is fixed to the outer end 50b of the stop lever 50. The tension spring 49 is connected by a wire or the like.
When the second lever 34 is tilted against the biasing force in the V direction, the lower end 34b side of the second lever 34 is pressed by the contact surface 52b, and the second lever 34 is tilted in the direction of the arrow U.

In the figure, reference numeral 55 indicates a limit bolt 57 screwed into a screw hole 56 formed in the upper wall of the link case 12, a rotation stopper nut 58 screwed into the upwardly projecting end of the limit bolt 57, and A rack movement limiting device consisting of a cap nut 59, which adjusts the screwing amount of the limiting bolt 57 to adjust the vertical position of the conical locking portion 60 provided at the lower end of the limiting bolt 57. At the position where the locking part 60 abuts the slope part 61 formed at the upper end of the rack connecting member 37, the movement of the control rack 35 in the (+) direction is restricted and the maximum injection amount of the fuel pump 11 is adjusted. It is supposed to be decided.

The link device of the present invention has the above-mentioned configuration, and its operation will now be explained with reference to FIGS. 4 to 6, which conceptually show each member.

In the figure, the same elements as in FIGS. 2 and 3 are designated by the same reference numerals.

First, during normal engine operation, the hydraulic governor 22 is driven in accordance with the rotation of the fuel pump camshaft 16, and the terminal shaft 25, which is its output shaft, rotates, causing the terminal lever 26 to move, for example, as shown in the solid line in FIG. When the letter control lever 31 and the second lever 33 connected to the link 30 tilt around the spindle 27, when the letter control lever 31 and the second lever 33 are rotated in the decreasing direction ((-) direction) from the position to the broken line position, the second lever is rotated. 3
A second lever 34 supported by a pin 32 at the lower end of 3
However, the upper end 34a of the second lever 34 tilts to the left in the drawing, centered around the connecting pin 40 fitted into the sliding groove 43 of the third lever 42, whose position is secured by the biasing spring 49, and the upper end 34a of the second lever 34 If the control rack 35 connected to the engine via the connecting link 38 is pulled in the decreasing direction ((-) direction), the amount of fuel supplied by the fuel injection pump 11 decreases, and conversely, the engine speed becomes too low. A link action opposite to that described above occurs, and the amount of fuel supplied increases, and the engine speed is maintained constant around the set value of the hydraulic governor 22.

On the other hand, the fuel injection pump 11 reaches the set maximum fuel injection amount, and the control rack 35 comes into contact with the restriction bolt 57 of the rack movement restriction device 55 as shown in FIG. 5, and moves in the fuel increasing direction ((+) direction). When the terminal lever 26 of the hydraulic governor 22 tilts in the fuel increasing direction ((+) direction) shown by the broken line even though the movement of the
The control lever 31 and the second
The lever 34 is forcibly tilted counterclockwise about the support shaft 27, but at this time, the second lever 34 connected to the second lever 33 rotates around its upper end 34a, and the third
By rotating the lever 42 in the direction of arrow U against the biasing force F of the tension spring 49, the amount of movement of the terminal lever 26 of the hydraulic governor 22 is absorbed as the amount of rotation of the third lever 42.

Next, when the engine is running and the position control of the control rack 35 by the hydraulic governor 22 is in a balanced state as shown by the solid line in FIG. 54 and the stop lever 52 integrated with the stop bundle 54 presses and turns the third lever 42 in the direction of the arrow U against the biasing force F of the tension spring 49.
The second lever 34 connected to the lever 42 rotates counterclockwise around the pin 32 at the lower end of the lever 33 which is in a substantially stationary state, and moves the control rack 35 in the fuel reduction direction ( (-) direction), the injection amount of the fuel pump 11 decreases rapidly and the engine stops.

As can be seen from the above description of the operation, when the position of the control rack 35 is controlled by the normal hydraulic governor 22, the biasing force F of the tension spring 49 overcomes the sliding resistance of the control rack 35, etc., and the third lever 42 while locking the control rack 3 at the stop position side.
5 is at its maximum position and its movement is restricted by the restriction device 55, it is necessary to set a size that allows the third lever 42 to rotate in the U direction due to the rotational output of the terminal shaft 25 of the hydraulic governor 22. be.

As described above, the link device of the present invention has a plurality of links,
In combination with a tension spring, the length of the link between the hydraulic governor and the control rack is absorbed when the fuel pump reaches its maximum injection amount.
Compared to conventional shock absorbing mechanisms in which a compression spring with a built-in cylinder is interposed in the link system, the link itself moves more smoothly, and the link device itself can be made smaller, making it easier to design the engine. In addition to improving the degree of freedom of the engine, the entire linkage device can be housed in the case, making it easy to automatically supply lubricating oil to rotating parts, extending the life of the engine, etc. Demonstrates the effect of

[Brief explanation of drawings]

Fig. 1 is a schematic diagram showing an example of a conventional buffer mechanism between a hydraulic governor and a fuel pump, and Figs. 2 and 3 are sectional views showing an example of a fuel pump control mechanism to which the link device of the present invention is applied. FIG. 3 is a sectional view taken along the line II in FIG. 2. In addition, Figures 4 to 6 are conceptual diagrams for explaining the action of the link device of the present invention. Figure 4 is for normal operation, Figure 5 is for full-rotation stop, and Figure 6 is for engine stop operation. The operation of each is shown. 11...Fuel injection pump, 22...Hydraulic governor, 25...Terminal shaft, 33
... Intermediate lever, 34... Second lever, 35.
...Control rack, 42...3rd lever 49...-Biasing spring (tension spring).

Claims (1)

[Scope of utility model registration request] A linkage device for hydraulically transmitting the actuation of a governor to a control rack of a fuel pump, the linkage device comprising a first lever, a second lever and a third lever, the first lever being connected to a terminal of a hydraulic governor. The third lever is a lever that tilts in conjunction with the shaft, and the third lever is rotatably supported at a position on the extending side of the swinging end of the third lever, and is biased toward the stop position by a biasing spring. a lever, and the second lever is at a swinging end of the second lever,
A fuel pump control characterized in that the lever is supported at a substantially central portion thereof, has one end engaged with a swinging end of the third lever, and has the other end connected to a control rack of the fuel pump. link device.