JP3826691B2 - Fuel pump mounting structure - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a fuel pump mounting structure when a fuel pump is driven by a camshaft that drives a valve of an engine.
[0002]
[Prior art]
In-cylinder fuel-injected gasoline engines require a particularly high fuel pressure, so the high-pressure fuel pump is conventionally driven by the camshaft that drives the intake valve. If it is arranged, the total length of the engine becomes large, so there is one in which a high-pressure fuel pump is attached to the upper surface of the rocker cover located above the camshaft.
However, in this case, in order to accurately position the high-pressure fuel pump with respect to the cylinder head, the rocker cover to which the high-pressure fuel pump is attached needs to be directly and firmly attached to the cylinder head without loosening. There is a problem that the outer surface of the rocker cover becomes the radiation surface of the valve sound, and the shielding performance of the valve sound by the rocker cover is remarkably deteriorated. Also, the rocker cover is divided into two parts and the high pressure fuel pump is attached. There is also a method of firmly attaching the rocker cover part directly to the cylinder head, and attaching the other part of the rocker cover to the cylinder head via a cushioning material, but the radiation area of the valve sound is reduced so much, A decrease in sound insulation performance is inevitable.
[0003]
[Problems to be solved by the invention]
The present invention is intended to allow a fuel pump to be firmly attached without increasing the overall length of the engine when the fuel pump is driven by a camshaft that drives a valve of the engine.
[0004]
[Means for Solving the Problems]
Therefore, the fuel pump mounting structure according to the present invention drives the valve of the engine, and, Rutotomoni each cylinder located remotely axis horizontal cam shaft in the axial direction of each rotatably supported by the cam shaft A cam cap fixed to the head and a wall portion integrally connecting the outer portions of the cam caps, and a fuel pump driven by the cam shaft is fixed to the wall portion from the outside ; The axis of the drive shaft of the fuel pump is arranged substantially horizontally perpendicular to the axial direction of the cam shaft .
[0005]
That is, the cam cap for rotatably supporting each camshaft is fixed to the Rutotomoni respective cylinder heads are spaced apart in the axial direction of the camshaft, their outer portions are integrally connected by a wall portion, a cam shaft Since the fuel pump driven by is attached to the wall from the outside, the fuel pump is supported by a plurality of cam caps fixed to the cylinder head side, so the fuel pump is easily and firmly supported is thereby it becomes possible, also, since the fuel pump is disposed perpendicular substantially horizontal and the axial direction of the horizontal cam shaft, also the fuel pump is being driven by the cam shaft, to increase the overall length of the engine no further, the fuel pump has been arranged on the outer side of the cam cap, not arranged thereabove, the cam cap Can be arranged to rocker cover above the fine wall, it is possible to satisfactorily retain the sound insulation performance of the rocker cover.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention shown in the drawings will be described.
The cylinder head 1 of the in-cylinder fuel injection type 4-cylinder gasoline engine is formed with an intake port 3 connected to an intake pipe 2 and an exhaust port 4 connected to an exhaust pipe (not shown). An intake valve 5 and an exhaust valve 6 are arranged at the opening portions of the intake port 3 and the exhaust port 4 respectively, and the intake valve 5 and the exhaust valve 6 are respectively formed by a cam 9 and a cam 10 formed on a cam shaft 7 and a cam shaft 8, respectively. Driven to open and close the intake port 3 and the exhaust port 4 respectively.
[0007]
On the other hand, the support member 11 includes a rear cam cap 12, an intermediate cam cap 13 disposed away from the rear cam cap 12 in the axial direction of the cam shaft 7, and outer portions of the rear cam cap 12 and the intermediate cam cap 13. Each of the rear cam cap 12 and the intermediate cam cap 13 is provided with a bearing 14 (not shown) on the cylinder head 1 side. The rear end portion of the camshaft 7 is sandwiched from above and below by bolts to the upper surface of the rear end portion of the cylinder head 1, and the rear end portion of the camshaft 7 is rotatably supported. The inner portions of the rear cam cap 12 and the intermediate cam cap 13 are separated from each other in the axial direction of the cam shaft 7.
[0008]
Further, the support member 11 is bolted directly to the cylinder head 1 side without loosening at the rear cam cap 12 and the intermediate cam cap 13 as described above, and at the same time, also to the cylinder head 1 side by the bolt hole 16. It is bolted directly without loosening and is firmly fixed to the cylinder head 1.
[0009]
Further, a semicircular void 17 and a screw hole 18 are formed on the side surface of the wall portion 14, and the fuel pump 20 is inserted through the flange 21 to connect the screw hole 18 on the side surface of the wall portion 14 to the cylinder head 1. The bolts 23 respectively screwed into the screw holes 22 formed in the outer surface of the rear end portion are fixed across the wall portion 14 and the respective outer surfaces of the rear end portion of the cylinder head 1. The convex portion 24 of the fuel pump 20 is formed on the semicircular space 17 of the wall portion 14 and the outer surface of the rear end portion of the cylinder head 1. The semicircular space 25 is inserted into the circular space and comes into contact with the cam 19 formed at the rear end of the cam shaft 7 so that the fuel pump 20 is directly driven by the cam 19. ing.
[0010]
Further, the rocker cover 30 that extends rearward from the front end portion of the cylinder head 1 to cover the upper surface of the cam shaft 7 and is fixed to the cylinder head 1 with a cushioning material interposed therebetween has a rear end portion 31, that is, an upper surface of the support member 11. 4 is placed on the shaded pattern portion 32 of FIG. 4 with a cushioning material interposed therebetween, and is fixed to the support member 11 by screws (not shown) screwed into the screw holes 33 on the upper surface of the support member 11.
[0011]
In the above-described device, the outer portions of the rear cam cap 12 and the intermediate cam cap 13 that are disposed apart from each other in the axial direction of the cam shaft 7 are integrally connected by the wall portion 14 and are driven by the cam shaft 7. Since the fuel pump 20 is supported by the plurality of cam caps 12 and 13 fixed to the cylinder head 1 respectively, the fuel pump 20 can be firmly attached easily. Further, since the fuel pump 20 is disposed substantially horizontally perpendicular to the axial direction of the cam shaft 7, even if the fuel pump 20 is directly driven by the cam shaft 7, the total length of the engine is not increased. .
[0012]
Further, since the rocker cover 30 is disposed above the support member 11 with the cushioning material interposed therebetween, even if the fuel pump 20 is attached to the support member 11 fixed to the cylinder head 1, the outer surface of the rocker cover 30. By eliminating the radiating surface of the valve sound and maintaining the sound insulation performance by the rocker cover 30, it is possible to maintain good engine merchandise, while the fuel pump 20 is in the axial direction of the camshaft 7. Since it is not arranged above the rocker cover 30, the installation volume of the breather, oil separator, etc. in the rocker cover 30 can be easily secured, so that the oil consumption is relatively low. It has the advantage that it can be easily suppressed and the engine exhaust gas can be maintained well.
[0013]
Moreover, since the inner portions of the rear cam cap 12 and the intermediate cam cap 13 in the support member 11 are separated from each other in the axial direction of the cam shaft 7, the cam 9 is formed from the inner side of the cam 9 formed on the cam shaft 7. Since the direction A in which the thickness gauge can be inserted between the intake valve 5 and the intake valve 5 side is relatively horizontal as shown in FIG. 1, accurate measurement with the thickness gauge is facilitated. It has a practically excellent feature that it can easily improve the performance and maintainability.
[0014]
【The invention's effect】
In the fuel pump mounting structure according to the present invention, the outer portion of the cam cap wall respectively Rutotomoni arranged axially spaced to rotatably support the camshaft respectively are secured to the cylinder head of the camshaft The fuel pump, which is integrally connected and driven by the camshaft, is attached to the wall portion from the outside, so that the fuel pump can be easily and firmly supported, and the fuel pump has a horizontal camshaft. Since the fuel pump is driven by a camshaft, the engine is not increased in length even if the fuel pump is driven by a camshaft , and the fuel pump is placed outside the cam cap. Te, since thereabove not disposed, and can place the rocker cover above the cam cap and the wall portion, good sound insulation performance by the rocker cover It can be held to.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view of an embodiment of the present invention.
FIG. 2 is a top view of essential parts of the embodiment.
FIG. 3 is a view taken along arrow III in FIG.
FIG. 4 is a perspective view of a main part of the embodiment.
[Explanation of symbols]
1 Cylinder Head 5 Intake Valve 7 Cam Shaft 9 Cam 11 Support Member 12 Rear Cam Cap 13 Intermediate Cam Cap 14 Wall 19 Cam 20 Fuel Pump 30 Rocker Cover

Claims (1)

Drives the valve of the engine, and a cam cap axis is fixed a horizontal cam shaft to respectively rotatably supported by Rutotomoni respective cylinder heads are spaced apart in the axial direction of the camshaft, each cam cap A fuel pump driven by the cam shaft is fixed to the wall portion from the outside, and an axis of the fuel pump drive shaft is connected to the cam shaft. A fuel pump mounting structure configured to be disposed substantially horizontally perpendicular to the axial direction.

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