JPH0777134A - Driving shaft fixing device for fuel injection pump - Google Patents

Abstract

PURPOSE:To match the specified rotational position of a fuel injection pump mounted a timer with the specified rotational position of a crank shaft in an internal combustion engine with high accuracy without depending on only the eyesight of a worker. CONSTITUTION:A pin fitting hole 61 is formed on the outer circumference of a timer flange 60 in which a relative rotational angle is regulated in relation to the pump cam shaft 3 of a fuel injection pump 1. The flat plate part 63b of the end part side of a pin fitting hole 61 whose U-shaped groove 63a is provided on the other end part is temporarily fixed to a pump main body 2 by a bolt 66 so as to fine adjusting a relative rotational angle in relation to a pump main body 2. An end part 64a of a pin 64 is temporarily fit to the pin fitting hole 61, and the other end part 64b is temporarily locked with the U-shaped groove 63a. It is thus possible to prevent rotational position slide of the cam shaft 3 of the fuel injection pump 1 at the time of transportation of the injection pump 1, and also connect an injection pump side driving shaft and an engine side driving shaft to each other on an optimal rotational angle position.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention, when mounting a fuel injection pump on an internal combustion engine, rotates the camshaft of the internal combustion engine so that the camshaft of the fuel injection pump is coupled to the crankshaft at an appropriate rotational angle position. The present invention relates to a camshaft fixing device for a fuel injection pump that fixes an angular position.

[0002]

2. Description of the Related Art When mounting a fuel injection pump on an internal combustion engine, it is necessary to set the rotational angle relationship between the crankshaft of the internal combustion engine and the camshaft of the fuel injection pump to a specified proper state. This is because the fuel injection operation needs to be properly executed in correspondence with the proper valve opening / closing timing of the internal combustion engine.

However, in a normal fuel injection pump, the camshaft of the fuel injection pump can freely rotate when it is not attached to the internal combustion engine. Therefore, the camshaft of this injection pump has the best sitting position. It has rotated to the position and is in a stable state at that position. In this comfortable sitting state, the camshaft is not normally held at the proper rotation angle position when it is mounted on the internal combustion engine.

For this reason, in order to set the camshaft of the fuel injection pump at the proper rotation angle position, it is proposed to attach a mark by a line indicating the proper rotation angle position to the timer flange connected to the camshaft and the pump body. Has been done. Then, when the injection pump is mounted on the internal combustion engine, the camshaft is rotated until the mark on the timer flange and the mark on the pump body match, and until the marks match, the timer flange and the drive shaft such as the crankshaft of the internal combustion engine. Are combined so that the rotational angle positional relationship between the camshaft of the fuel injection pump and the crankshaft of the engine is set optimally.

[0005]

However, according to the alignment method for forming the marks as described above, when the fuel injection pump is mounted on the internal combustion engine, the operator can check the states of the marks on the timer flange and the marks on the pump body. Since it is necessary to mount the fuel injection pump on the internal combustion engine while visually confirming it, there is a problem that the accuracy of aligning the mark on the timer flange with the mark on the pump body is lowered.
For example, it is said that an error in the relative rotation angle between the drive shaft such as the crankshaft of the engine and the camshaft of the fuel injection pump is ± 0.3 °.

The present invention has been made in view of the above problems, and a fuel injection device equipped with a timer is provided by providing a positioning mechanism that can be easily operated without relying only on the visual inspection of an operator. Provided is a drive shaft fixing device for a fuel injection pump capable of accurately aligning a specific rotation position of a pump with a specific rotation position of a crankshaft of an internal combustion engine, that is, capable of optimally adjusting a fuel injection timing. The purpose is to do.

[0007]

A drive shaft fixing device of a fuel injection pump for achieving the above object of the present invention is rotatably supported by a pump body of the fuel injection pump, and one end of the drive shaft fixing device is separated from the pump body. It has a pump side drive shaft that is projected, a hub that is fixed to this pump side drive shaft, and a timer flange that is fixed to the internal combustion engine side drive shaft and forms a pin fitting portion on the outer periphery. A timer in which the relative rotation angle between the timer flange and the hub is adjusted by centrifugal force generated according to the increase and decrease, and a pin locking portion provided at one end provided between the timer flange and the pump body. And a lock plate having a long hole capable of finely adjusting the relative rotation angle between the pump body and the timer flange at the other end, and one end provisionally fitted to the pin fitting part, The other end Is provided with a pin that is temporarily locked to the pin locking portion, and screw tightening means that can be inserted into the elongated hole of the lock plate to temporarily fix the timer flange and the pump body. Adopt a configuration.

[0008]

Before the shipment of the fuel injection pump, the rotation of the drive shaft of the injection pump whose fuel injection timing is set in advance is prevented, and when the fuel injection pump is attached to the internal combustion engine body, the drive shaft of the injection pump is prevented. The internal combustion engine side drive shaft and the internal combustion engine side drive shaft can be connected by a simple operation in an appropriate rotational positional relationship.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 4 show a camshaft fixing device for a fuel injection pump with a timer, which is mounted on a diesel engine. As shown in FIG. 1, in the fuel injection pump 1, the plunger of the fuel pressure feeding means (not shown) housed in the pump body 2 is pressed against the tappet by the load of the spring, and the tappet is pressed against the cam of the pump camshaft 3. It is pressed. The plunger is reciprocated up and down in the cylinder via the tappet by the rotation of the pump cam shaft 3 to pump fuel. The fuel that is pumped by the rise of the plunger reaches the injection nozzle of the diesel engine from the connection port of each delivery valve 4 through a high pressure pipe (not shown).

The pump cam shaft 3 rotatably supported by the pump body 2 has one end projecting outside the pump body 2, and the projecting portion has a tapered portion 3a. The fuel injection pump timer 18 fitted in the tapered portion 3 a is connected to the shaft coupling device 5. The coupling flange 52 for connecting the drive shaft on the diesel engine side (not shown) has the drive shaft on the engine side key-fitted into the shaft hole 52a, and the shaft hole 52a is formed in the portion projecting radially outward from the flange shoulder 52b. A pair of screw holes 52 on both sides of the center
have c. Further, in the coupling flange 52, the narrow slit 52d is formed from the outermost peripheral edge 52e of the flange to the shaft hole 52.
It linearly penetrates a.

FIG. 1 shows a state before the drive shaft on the engine side is attached to the coupling flange 52, but when the fuel injection pump is mounted on the engine, the coupling flange 52 narrows the slit 52d. The drive bolt on the engine side and the coupling flange 52 are connected by the tightening bolt 24. The coupling flange 52 and the first thin steel plate 53 are formed by the bush 25 and the collar 26.
It is fastened and fixed by bolts 54 and nuts 55 via. The first thin steel plate 53 is a thin plate-shaped flexible member so as to absorb the axial deviation due to the eccentricity even if the engine-side drive shaft and the pump camshaft 3 are eccentric. First thin steel plate 53 and coupling cloth 28
Are fastened and fixed by bolts 30 via a collar 31 and a bush 32.

The second thin steel plate 12 is connected to the cup ring cloth 28 by a bolt through a collar and a bush (not shown). The second thin steel plate 12 is screwed to the timer flange 60 of the fuel injection pump timer 18 with a bolt 44 via a collar 40 and a bush 42. A hub (not shown) is fixed to the tapered portion 3a of the pump camshaft 3 of the injection pump 1 by a round nut 67, and a timer flange 60 is connected to this hub via a spring and a weight. The weight is operated against the spring by the centrifugal force generated by the rotation during the operation of the engine, so that the relative rotation angle between the hub and the timer flange is changed.

In the camshaft fixing device 62 of the fuel injection pump 1, the timer flange for the fuel injection pump timer 18 is provided on the outer peripheral surface of the timer flange 60 when the plunger of the injection pump comes to the pumping start point position in advance. A fitting groove 6 for fitting a pin, which is formed almost directly above the outer circumference of the 60.
1, a lock plate 63, a pin 64, lock plate mounting bolts 65, 66 and the like.

As shown in FIG. 4, the lock plate 63 has an L-shaped cross section, and a U-shaped groove 63a having a width across flats is formed at one end in the longitudinal direction of the lock plate 63 and the other end thereof. Oblong holes 63c and 63d are formed in the flat plate portion 63b formed in. The elongated holes 63c and 63d are formed in an arc shape around the axis of the pump camshaft 3 as shown in FIG.

The pin 64 has one end 64a when temporarily fixed.
Fits into the fitting groove 61 of the timer flange 60, and the other end 64b fits into the U-shaped groove 63a of the lock plate 63. The lock plate attachment bolts 65 and 66 are bolts for attaching the lock plate 63 to the pump body when temporarily fixed.

Next, regarding the camshaft fixing device of the fuel injection pump according to the present embodiment, (1) when the timing is set,
(2) When mounted on an internal combustion engine (diesel engine) and (3) when the internal combustion engine is operating will be described separately. (1) At timing setting Before setting the timing, the plunger (not shown) of the injection pump 1 is stopped at the pre-stroke position, that is, the pressure feeding start point position. At this time, the coupling flange 60 is previously fixed to the pump camshaft 3 by the round nut 67, and the pin fitting groove 61 is located almost right above the outermost circumference of the timer flange 60 at the position of the plunger pumping start point. Set to. Next, one end 64a of the pin 64 is inserted into the fitting groove 61, and then the pin 6
A U-shaped groove 63a having a width across flats of the lock plate 63 is fitted to the other end 64b of the lock plate 63, and in this state, the bolts 65 and 66 are tightened to fix the lock plate 63 to the pump body 2. 1 to 4 show the state after the timing is set. The fuel injection pump 1 is shipped in the state after this timing setting. After shipment, this fuel injection pump 1 is mounted on a diesel engine.

(2) When the fuel injection pump is mounted on the internal combustion engine The fuel injection pump shipped in the state shown in FIGS. 1 to 4 is rotationally angularly aligned with the crankshaft of the internal combustion engine. When the injection pump is mounted on the internal combustion engine, the crankshaft of the internal combustion engine is fixed in advance at an appropriate position, and in this state, the drive shaft on the internal combustion engine side that is fixed in correspondence with the crankshaft and the rotation angle position are Flange 5
It is fixed to the second shaft hole 52a. That is, when the drive shaft on the internal combustion engine side is fitted into the shaft hole 52a of the coupling flange 52, the drive shaft on the internal combustion engine side and the shaft hole 52a of the coupling flange 52 are formed by the coupling flange elongated holes 52c.
The shafts of the key fitting are aligned with each other, and the drive shaft on the engine side and the coupling flange 52 are tightened and fixed by the tightening bolts 24. Then the bolt 54 and nut 55
The thin steel plate 53 and the coupling flange 52 are fastened and fixed. In this state, the injection timings of the drive shaft of the internal combustion engine and the pump camshaft 3 are properly set.

At the end of mounting the injection pump before operating the internal combustion engine, the bolts 65 and 66 are loosened and the lock plate 63 is removed. Then, the pin 64 is pulled out from the fitting groove 61. In this way, the lock plate 63 and the pin 6 which are the respective parts constituting the coupling fixing device of the injection pump
4. Remove bolts 65, 66 from injection pump 1. In this case, for fine adjustment of the rotational angle positions of the crankshaft of the internal combustion engine and the pump camshaft 3 of the injection pump,
The bolts 65 and 66 are turned within the range of the elongated holes 63c and 63d of the lock plate 63 to perform fine adjustment.

(3) During Operation of Internal Combustion Engine During operation of the fuel injection pump, the torque of the internal combustion engine varies from the drive shaft on the engine side to the coupling flange 52, the first thin steel plate 53, the coupling cross 28, and the second. It is transmitted to the pump camshaft 3 of the injection pump through the thin steel plate 12 and the fuel injection pump timer 18. In this case, even if the axial center of the drive shaft on the engine side and the axial center of the pump cam shaft 3 do not coincide with each other, the elastic vibration of the first thin steel plate 53 and the second thin steel plate 12 causes eccentric rotation vibration. Absorbs
The driving force can be properly transmitted.

According to the above-described embodiment, the coupling plunge 60 fixed to the pump camshaft 3 is temporarily fixed to the pump main body 2 by the lock plate 63, the pin 64 and the bolts 65 and 66, so that the operator can see it visually. The rotation angle position of the pump camshaft 3 is adjusted in advance by reducing the positioning load. Further, in this case, the lock pre-plate 63 and the lock pin 64 are provided on the fuel injection pump side of the pump body 2 rather than on the coupling flange 60 side of the internal combustion engine side.
Since the bolts 65 and 66 are provided, there is an effect that the work of connecting the fuel injection pump to the internal combustion engine can be easily performed.

[0021]

As described above, according to the drive shaft fixing device for a fuel injection pump of the present invention, the fuel injection is performed when the fuel injection pump is transported to the internal combustion engine or when the fuel injection pump is attached to the internal combustion engine. It is possible to prevent the displacement of the rotational position of the camshaft of the pump and to connect the fuel injection pump equipped with the timer and the internal combustion engine side drive shaft at an appropriate rotational position by a simple operation.

Further, according to the drive shaft fixing device of the fuel injection pump of the present invention, the accuracy of the relative rotation angle alignment between the internal combustion engine side drive shaft and the injection pump side can be greatly improved, so that the fuel injection timing can be improved. There is a remarkable effect such as the improvement of accuracy and reduction of exhaust gas emission.

[Brief description of drawings]

FIG. 1 is a side view showing a fixed shaft fixing device of a fuel injection pump according to an embodiment of the present invention.

FIG. 2 is an enlarged plan view of an arrow II portion shown in FIG.

FIG. 3 is a view taken in the direction of arrow III shown in FIG.

FIG. 4 is a partial perspective view showing a drive shaft fixing device of a fuel injection pump according to an embodiment of the present invention.

[Explanation of symbols]

 1 Fuel Injection Pump 2 Pump Body 3 Pump Cam Shaft (Pump Drive Shaft) 18 Fuel Injection Pump Timer 60 Timer Flange 61 Fitting Hole (Pin Fitting Part) 62 Camshaft Fixing Device (Drive Shaft Fixing Device) 63 Lock Plate 63a U-shaped groove (pin locking portion) 63b Flat plate portion 63c Long hole 63d Long hole 64 pin 64a One end portion 64b Other end portion 65 Lock plate mounting bolt (screw tightening means) 66 Lock plate mounting bolt (screw tightening) (Attachment)

Claims (1)

[Claims] 1. A pump-side drive shaft rotatably supported by a pump body of a fuel injection pump and having one end protruding from the pump body, a hub fixed to the pump-side drive shaft, and an internal combustion engine side. It has a timer flange that is fixed to the drive shaft and forms a pin fitting portion on the outer circumference, and the relative rotation angle between the timer flange and the hub is adjusted by the centrifugal force generated according to the increase or decrease in the rotation speed. A timer, provided between the timer flange and the pump body, having a pin locking portion at one end, and finely adjusting the relative rotation angle between the pump body and the timer flange at the other end. A lock plate having a possible elongated hole; a pin having one end temporarily fitted to the pin fitting portion and the other end temporarily fitted to the pin locking portion; and the elongated hole of the lock plate In front of Drive shaft fixing apparatus for a fuel injection pump, characterized in that the timer flange and said pump body and means with temporary fixable screw tightening.