JPS6341528Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Field of Industrial Application) The present invention relates to a drive device for an oil pump that pumps engine oil to each lubricated part of an internal combustion engine. The present invention relates to a drive device for an oil pump.

(Prior Art) In internal combustion engines, an oil pump that sucks up engine oil from an oil pan and pumps it to various parts is often driven by a crankshaft or a camshaft. conventionally,
When an oil pump is driven by a crankshaft, the oil pump is generally installed within the crankcase. In this way, there is no need to provide a separate lubrication system for lubricating the drive device of the oil pump, and the structure becomes simple.

However, in this case, since the oil pump is located inside the crankcase, each time the oil pump is inspected, the entire engine must be disassembled, which is a very time-consuming process. becomes.

For this reason, as shown in Japanese Utility Model Application Publication No. 58-183911, a rotary oil pump is fitted into the side wall of the crankcase, and the drive shaft of the oil pump protrudes into the crankcase. A system has been proposed in which the rotation of the shaft is transmitted to the oil pump via a driven gear fixed to the drive shaft. In this way, the oil pump drive gear is located inside the crankcase, so no special configuration is required for its lubrication, and the oil pump can be inspected from outside the crankcase. This makes the work easier.

(Problems to be solved by the invention) By the way, the lubricating oil supply device disclosed in the above publication has a structure in which the pump body and the driven gear are integrally fixed, and when the oil pump is removed, the driven gear must also be removed. Both require removal from the crankcase. For this reason, the pump assembly opening provided in the side wall of the crankcase has a diameter large enough to allow the driven gear to pass through. However, providing such a large-diameter opening in the crankcase reduces the strength of the crankcase, requiring reinforcement, which not only increases weight, but also limits the installation location of the oil pump. This reduces the freedom of the overall layout. Furthermore, with such a large diameter opening, it is difficult to completely seal the surrounding area.

The pump body and the driven gear may be separated, but in that case, the problem is how to support the driven gear and how to efficiently transmit its rotation to the pump body.

The present invention was developed in view of these circumstances, and its purpose is to simply provide a small-diameter opening in the side wall of the crankcase so that the oil pump, which is attached to the outside of the side wall, can be inserted into the crankcase. In addition to being driven by a driven gear that is installed, the oil pump can be removed, thereby making maintenance inspections and parts replacement of the oil pump easier. be.

Another object of the present invention is to support the driven gear at both ends when the oil pump is driven, thereby ensuring smooth transmission of rotational force, and to ensure that the driven gear is supported even when the oil pump is removed. It is to be.

(Means for Solving the Problems) In order to achieve this object, the present invention provides a driven gear driven by a crankshaft that is connected to the inner surface of a side wall of the crankcase and the crankcase that is located opposite to the inner surface of the side wall of the crankcase. The driven gear is arranged between the inner wall of the crankshaft, for example, a bearing cap that supports the crankshaft, so that the driven gear is supported even by itself by the driven gear support means provided on the inner wall, and the driven gear is provided with The drive shaft of the rotary oil pump, which is inserted into the shaft hole so as to protrude inward through the side wall of the crankcase and is rotatably supported by the penetrating portion, is removably fitted into the shaft hole. I have to. What is a driven gear and a drive shaft?
They are connected by spline fitting or the like where they engage with each other so that rotational force is transmitted.

(Function) With this configuration, when the oil pump is assembled to the outer surface of the side wall of the crankcase and its drive shaft is connected to the driven gear, the rotational force of the crankshaft is transmitted to the oil pump through the driven gear. . Therefore, the oil pump driving gear can be located inside the crankcase while driving the oil pump outside the crankcase. Furthermore, at that time, the driven gear is supported from both sides by the driven gear support means on the internal wall and the drive shaft passing through the side wall of the crankcase, so the driven gear and pump drive shaft are supported correctly and rotation is transmitted smoothly. It becomes like this.

Then, by pulling out the drive shaft from the driven gear, the oil pump can be removed while leaving the driven gear inside the crankcase. Therefore, as long as a small diameter opening is provided in the side wall of the crankcase through which the drive shaft passes, the oil pump can be replaced.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of the present invention will be described with

The figures show an embodiment of an oil pump drive device according to the present invention, in which FIG. 1 is a longitudinal sectional view thereof, and FIG. 2 is a cutaway front view of the oil pump portion thereof. Moreover, FIG. 3 is an exploded view showing a state in which the oil pump is removed.

As is clear from Fig. 1, crankcase 1
A crankshaft 4 supported by the lower end of the cylinder block 2 and a bearing cap 3 is disposed inside. crankshaft 4
The cylinder block 2 and bearing cap 3 supporting the end of the crankcase 1 are attached to the side wall 1a of the crankcase 1.
The inner wall of the crankcase 1 is located close to and opposite to the inner wall of the crankcase 1.

A drive gear 5 is integrally provided at the end of the crankshaft 4, and a driven gear 6 is meshed with the drive gear 5. A shaft hole 7 with a spline groove 7a formed on the inner surface is provided in the center of the driven gear 6, and a nut having a threaded hole 8a concentric with the shaft hole 7 is provided at the end of the shaft hole 7 on the bearing cap 3 side. 8 are integrally fixed. This nut 8 is provided with a shaft hole 8b at the end opposite to the screw hole 8a, and a set pin 9 that is press-fitted and fixed into the bearing cap 3, which is an internal wall, is fitted into this shaft hole 8b. The nut 8 and, therefore, the driven gear 6 are rotatably supported. That is, in this embodiment, the set pin 9 constitutes driven gear supporting means.

A trochoidal oil pump 10 is attached to the outer surface of the side wall 1a of the crankcase 1 at a position corresponding to the driven gear 6. As shown in FIGS. 1 and 2, this oil pump 10
is the inner rotor 11 concentric with the driven gear 6
and an outer rotor 12 which is eccentric from this, and these inner rotor 11 and outer rotor 12 are rotatably housed in a pump casing 14 which is tightly tightened to the side wall 1a of the crankcase 1 with bolts 13. It's becoming like that. On the side wall 1a of the crankcase 1,
A suction port 15 and a discharge port 16 are provided which communicate with the pump chamber 10a formed between the inner rotor 11 and the outer rotor 12.
is connected to a filter chamber 17 provided in an oil pan at the center of the bottom surface of the crankcase 1, and the discharge port 16 is connected to a required lubricating part through a main gear rally (not shown).

As shown in FIG.
One end of a rotor drive shaft 18 is spline-fitted into the center of the rotor drive shaft 1 . The other end of the drive shaft 18 extends into the crankcase 1 through an opening 1b formed in the side wall 1a of the crankcase 1, and has spline teeth 18a on the outer peripheral surface of the inner end thereof. is formed so that it can be spline-fitted into the shaft hole 7 having the spline groove 7a of the driven gear 6. The opening 1b of the side wall 1a of the crankcase 1 constitutes a bearing surface that rotatably supports the drive shaft 8, and its end protrudes inward to a position close to the driven gear 6. The inner rotor 11 and the drive shaft 18 are provided with a bolt hole 19 at their axes, and by tightening the bolt 20 inserted through the bolt hole 19 into the threaded hole 8a of the nut 8, the inner rotor 11, The drive shaft 18 and the driven gear 6 are integrally fixed to each other.

Next, the operation of the oil pump drive device configured as described above will be explained.

As shown in FIG.
When 0 is assembled, the driven gear 6
is the rotor drive shaft 1 fitted on one side.
8 is supported by the side wall 1a of the crankcase 1 at its penetrating portion, that is, the opening 1b, and the other side is supported by the bearing cap 3 via a nut 8 and a set pin 9. Therefore, both sides of the driven gear 6 are supported at positions close to each other.

When the crankshaft 4 rotates in this state, the drive gear 5 integrated with the crankshaft 4
rotates, and the driven gear 6 meshing with it is rotationally driven. Thereby, the rotor drive shaft 18 spline-fitted to the driven gear 6
rotates, and the inner rotor 11 of the oil pump 10
rotates. When the inner rotor 11 rotates, the outer rotor 12 also rotates in the same direction, but the gap between them, that is, the pump chamber 10a
Since the volume of the oil pan fluctuates, engine oil in the oil pan flows from the filter chamber 17 into the oil pump 10 through the suction port 15, and is pumped through the discharge port 16 to various parts. During this time, the sliding surfaces of the oil pump drive device, such as between the drive gear 5 and the driven gear 6 that mesh with each other, and between the nut 8 and the set pin 9, are sufficiently lubricated by the oil in the crankcase 1. .

When inspecting the oil pump 10, loosen the bolts 13 and remove the pump casing 14. At this time, the outer rotor 12 is also removed. Since the oil pump 10 is attached to the outer surface of the side wall 1a of the crankcase 1, its operation can be easily performed from the outside. and oil pump 1
0, further remove the bolt 20 from the nut 8 and pull it out. As a result, the inner rotor 11 is also removed, as shown in FIG. Further, by pulling out the drive shaft 18 in the axial direction, the spline fitting with the driven gear 6 is released, and the drive shaft 18 can be removed from the crankcase 1.

At this time, the driven gear 6 comes into contact with the end surface of the opening 1b of the crankcase side wall 1a while the nut 8 and set pin 9 remain fitted, so it will not fall off even if the drive shaft 18 is removed. . Therefore, even when a new drive shaft 18 is assembled, the driven gear 6 is held in a predetermined position, so that they can be easily spline-fitted. Then, by assembling the inner rotor 11, inserting the bolts 20 into the bolt holes 19 of the inner rotor 11 and the drive shaft 18, and tightening the bolts 20 to the nuts 8, the inner rotor 11, the drive shaft 18, and the driven gear 6 are fixed to each other. Ru. Next, by assembling the outer rotor 12 and the casing 14, the replacement work of the oil pump 10 is completed.

In this way, maintenance and inspection of the oil pump 10 can be performed from outside the crankcase 1, and the work of attaching and detaching the oil pump 10 is also facilitated. Moreover, when removing the oil pump 10, the driven gear 6
remains inside the crankcase 1, it is sufficient to provide the side wall 1a of the crankcase 1 with a small-diameter opening 1b through which the rotor drive shaft 18 passes, and the strength of the side wall 1a can be ensured sufficiently. , a sealing member for sealing between the casing 14 and the side wall 1 of the crankcase 1
It is only necessary to provide the sealing material between the material and the material a, and the sealing performance thereof can be improved.

Further, since the driven gear 6 is supported on both sides, there is a gap between the drive shaft 18 and the opening 1b of the crankcase 1, and between the nut 8 and the set pin 9.
This reduces the unbalanced load that is applied between the bearings and ensures the durability of the bearings. Further, since an unbalanced load is not transmitted to the oil pump 10 and rotational force is smoothly transmitted, the efficiency of the oil pump 10 is maintained at a high level.

Note that in the above embodiment, the inner rotor 1
1 and its drive shaft 18 are separate bodies that can be separated from each other, but they may be integrally formed. Further, although the driven gear 6 and the nut 8 are separate, the nut 8 may be formed by a part of the driven gear 6.

Further, the driven gear 6 is supported by the set pin 9 press-fitted into the bearing cap 3 as in the above embodiment, and is also supported by an appropriate support on the inner wall of the cylinder block 2, etc., which faces the side wall 1a of the crankcase 1 in close proximity. A bearing may be provided to rotatably support the shaft extending from one side of the driven gear 6. In short, the driven gear 6 only needs to be rotatably supported independently so that it will not fall off even when the drive shaft 18 is removed.

As the oil pump 10, in addition to the trochoid type pump as in the above embodiment, any appropriate rotary pump such as a gear type or a centrifugal type can be used.

(Effect of the invention) As is clear from the above explanation, according to the invention, one side of the driven gear that drives the rotary oil pump is rotatably supported by the driven gear support means inside the crankcase, and the driven gear The oil pump drive shaft, which penetrates the side wall of the crankcase and is supported by the side wall, is removably fitted into the shaft hole provided on the other side. The oil pump can be installed outside the crankcase simply by providing a small diameter opening through which the shaft can pass. Therefore, sufficient strength and sealing properties of the crankcase can be ensured, and maintenance and inspection of the oil pump and parts replacement can be done without disassembling the engine, without requiring special lubrication means for the driven gear, etc. This makes the work easier as it can be done from outside the crankcase.

Furthermore, since the driven gear is supported on both sides, the unbalanced load applied to its bearings is reduced, durability is improved, and the oil pump is driven more efficiently. Furthermore, since one side of the driven gear is supported by the support portion of the drive shaft, there is no need to provide a separate bearing.

[Brief explanation of the drawing]

Fig. 1 is a vertical cross-sectional view showing one embodiment of an oil pump drive device according to the present invention, Fig. 2 is a cutaway front view of the oil pump portion, and Fig. 3 is an exploded vertical cross-sectional view for explaining the state in which the oil pump is removed. 1...Crankcase, 1a...Side wall, 1b...Opening, 3...Bearing cap (inner wall), 4...Crankshaft, 5...Drive gear, 6...Driven gear, 7...Shaft hole, 9...Set pin (driven gear support means), 10...Oil pump, 11...Inner rotor, 12...Outer rotor, 18...Rotor drive shaft.

Claims (1)

[Scope of Claim for Utility Model Registration] A rotary oil pump is disposed on the outer surface of a side wall of the crankcase that is located close to and opposite to the inner wall in the crankcase, and the inner wall of the crankcase side wall is connected to the inner wall. A driven gear rotatably supported by driven gear support means provided on the inner wall thereof and rotationally driven in conjunction with the crankshaft is disposed between them, and a drive shaft for driving the oil pump is connected to the crankcase. It penetrates the side wall and protrudes inward, and is rotatably supported by the penetrating portion, and
A driving device for an oil pump in an internal combustion engine, the inner end of which is formed to be removably fitted into a shaft hole provided in the driven gear and capable of transmitting rotation.