JPH0676606U - Oil pump drive - Google Patents

Abstract

(57) [Summary] [Object] To provide an oil pump drive device in which an intermediate shaft and an oil pump can be integrally pulled out from an engine body. In an oil pump drive device, a rotational force of a crankshaft of an engine is transmitted to an input shaft 21 of an oil pump arranged on a side surface of an engine via an intermediate shaft 18 drivingly connected to the crankshaft. , The connecting portion of the intermediate shaft 18 and the input shaft 21 is formed by the concave portion 22 and the convex portion 23 in the axial direction which engage with each other to transmit the rotational force, and the radius which further engages with the concave portion and the convex portion. Directional recess 24
And the convex portion 25 is provided. The intermediate shaft 18 and the input shaft 21 can be separated in the radial direction but cannot be separated in the axial direction.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an oil pump drive device for driving an oil pump attached to an engine by a crankshaft of the engine.

[0002]

[Prior art]

 A two-cycle engine is conventionally known in which an oil pump is provided on the side of the engine body to pump and add lubricating oil (oil) into the air-fuel mixture in the intake system. Such a two-cycle engine is disclosed in JP-A-60-34532, JP-B-60-6571, and the like. In these engines, an intermediate shaft for driving an oil pump, which is drivingly connected to the crank shaft through a worm gear, is arranged in a direction orthogonal to the crank shaft, and an oil pump is provided at the outer end of the intermediate shaft. Pump input shaft is connected.

The connecting portion between the intermediate shaft and the input shaft is usually constructed as shown in FIG. In the figure, 01 is an engine body, 02 is an oil pump, 03 is a crankshaft, 04 is an intermediate shaft, and the portion surrounded by a circle A is a connecting portion between the intermediate shaft 04 and the input shaft of the oil pump 02. This connecting portion is formed by fitting an axial convex portion 07 formed on the end surface of the input shaft 06 of the oil pump 02 into an axial concave portion 05 formed on the end surface of the intermediate shaft 04. There is.

[0004]

[Problems to be solved]

 Since the intermediate shaft 04 and the input shaft 06, which are connected by the engagement of the concave portion 05 and the convex portion 07 in the axial direction in this way, can be easily disengaged in the axial direction, the oil pump 02 is removed from the engine body 01 when disassembling the engine. Then, the intermediate shaft 04 remains in the engine main body, and therefore it is necessary to further pull out the intermediate shaft from the engine main body. Since the intermediate shaft 04 does not project sufficiently from the side surface of the engine body after the engine pump 02 is removed, the pulling out work is not always easy, especially when the connecting portion A must be provided inside the engine body 01. It becomes difficult to take out the intermediate shaft.

Therefore, according to the present invention, the intermediate shaft 04 and the input shaft 06 can be easily engaged and disengaged, and the intermediate shaft can be withdrawn from the engine body integrally with the input shaft without separating the intermediate shaft from the input shaft. Another object of the present invention is to provide an oil pump drive device.

[0006]

[Means and Actions for Solving the Problems]

 Therefore, in the present invention, an oil pump for transmitting the rotational force of the crankshaft of the engine to the input shaft of the oil pump arranged on the side surface of the engine via the intermediate shaft drivingly connected to the crankshaft. In the drive device, the coupling portion between the intermediate shaft and the input shaft is formed by a concave portion and a convex portion in the axial direction that engage with each other to transmit the rotational force, and the radius that further engages with the concave portion and the convex portion. Directional recesses and protrusions are provided so that the intermediate shaft and the input shaft can be disengaged in the radial direction but not in the axial direction.

According to the present invention, both the shafts can be easily engaged and disengaged by moving the intermediate shaft and the input shaft in the radial direction, while the intermediate shaft and the input shaft can be easily engaged and disengaged by moving the input shaft in the axial direction. Since the shaft also moves in the same direction, the shaft can be taken out together with the oil pump during removal from the engine, improving workability when disassembling the engine.

[0008]

【Example】

 FIG. 2 is a cross-sectional view of an engine 1 equipped with an oil pump drive device according to the present invention. This engine 1 is integrated with a swing unit that swingably supports rear wheels in a motorcycle, and a transmission case 3 that also functions as a swing arm extending rearward is integrally formed on the left side of a crankcase 2 and a rear end of the transmission case 3 is formed. The axle 4 is pivotally supported. The rear axle 4 is driven from the crankshaft 5 of the engine 1 via a power transmission device housed in the transmission case 3.

Reference numeral 6 is a cylinder, 7 is a scavenging passage, 8 is an intake port, and 9 is an intake pipe. Due to the negative pressure generated in the crank chamber 11 during the upward stroke of the piston 10, the air-fuel mixture passes from the intake pipe 9 through the intake port 8. It is sucked by the crank 11, compressed in the downward stroke of the piston 10, and sent to the cylinder hole through the scavenging passage 7.

The intake pipe 9 is connected to a carburetor (not shown), a mixture of air and fuel is created in the carburetor, and oil is added to the mixture by an oil pump described later. Reference numeral 12 denotes an oil supply hole for guiding the oil in the air-fuel mixture from the scavenging passage 7 to the main bearing 13 and lubricating it. A negative pressure extraction pipe 14 communicating with this oil supply hole 12 extends from the crankcase 2. There is. The negative pressure extraction pipe 14 is connected to a negative pressure type fuel pump (not shown) for supplying the fuel, and supplies an operating negative pressure to the fuel pump. The negative pressure extraction pipe 14 may be communicated with another place, for example, a space between the main bearing 13 and an oil seal provided outside thereof, the scavenging passage 7 or the vicinity of the intake port 8.

The right end of the crankshaft 5 projects outside the crankcase 2, and a generator 15 and a cooling fan 16 are attached to this end. Further, inside the crankcase 2 and outside the right-side main shaft 13, a worm 17 is engraved on the crankshaft 5, and an intermediate shaft 18 for driving an oil pump is cranked through a worm gear 19 meshing with the worm 17. It is drivingly connected to the shaft 5.

FIG. 3 shows the right part of the crankcase 2 cut along various cross sections perpendicular to the crankshaft 5 and shows a part of each cross section in a fan shape. A section including the intermediate shaft 18 is shown in the fan-shaped portion.

As shown in FIG. 3, the intermediate shaft 18 engages a worm gear 19 formed on the inner end thereof with the worm 17 of the crank shaft 5 and extends outward in the direction perpendicular to the crank shaft 5. It is extended. An oil pump 20 is attached to the outer surface of the crankcase 2 on the extension of the intermediate shaft 18, and an input shaft 21 thereof projects toward the intermediate shaft 18 into the crankcase 2 and is joined at a joint portion A. ing.

In FIGS. 4 and 5, the joint portion A shown as an external view in FIG. 3 is enlarged and shown as a horizontal sectional view and a vertical sectional view, respectively. As can be seen from these drawings, the intermediate shaft 18 and the input shaft 21 are provided with a concave portion 22 and a convex portion 23 in the axial direction, respectively, on their respective end surfaces facing each other. Each of these uneven portions 22 and 23 crosses the corresponding axis and has planes 22a, 22a and 23a, 23a parallel to each other. The concave portion 22 and the convex portion 23 are fitted to each other by bringing the flat surfaces 22a, 22a into contact with each other. In each drawing, the gap between the portion on the intermediate shaft 18 side and the portion on the input shaft 21 side is exaggerated.

Further, a concave portion 24 extending in the radial direction of the intermediate shaft 18 is provided at the inner end portion of the concave portion 22, and a similar radial convex portion 25 is also provided at the tip of the convex portion 23. The concave and convex portions 24 and 25 of are fitted to each other. Like the recess 22, the recess 24 also traverses the intermediate shaft 18 and opens on both sides of the intermediate shaft 18.

Since the connecting portion A of the intermediate shaft 18 and the input shaft 21 is configured in this way, the rotational force of the intermediate shaft 18 is transmitted to the input shaft 21 via the flat surfaces 22a, 23a which engage with each other. The two shafts 18 and 21 are connected to each other in such a manner that the convex portions 23 and 25 fit into the concave portions 22 and 24 when they are relatively moved in the radial direction as shown by an arrow a in FIG. Can be done very easily. However, even if the combined shafts 18 and 21 are pulled in the axial direction as shown by the arrow b in FIG. 5, since the surface 24a of the concave portion 24 and the surface 25a of the convex portion 25 are engaged, the two shafts are separated. It cannot be made to move, and both shafts must be moved in the radial direction relative to each other.

Therefore, when removing the oil pump 20 of FIG. 3 from the crankcase 2, if the mounting bolt is removed and the oil pump 20 released from the crankcase 2 is moved in the radial direction with respect to the axis of the intermediate shaft 18, Since the projections 23 and 25 of the input shaft 21 are separated from the recesses 22 and 24 of the intermediate shaft 18, the oil pump 20 can be removed, but if the intermediate shaft 18 also needs to be removed from the crankcase 2 subsequently. Is difficult to extract from the crankcase 2 because the end of the intermediate shaft 18 is located deep inside the crankcase 2.

In this case, if the oil pump 20 from which the mounting bolt is removed is moved in the axial direction as it is, the convex portion 25 of the input shaft 21 is engaged with the concave portion 24 of the intermediate shaft 18. 18 is also pulled out from the crankcase 2 together with the input shaft 21, thus improving workability when disassembling the engine.

The shapes of the concave portions 22 and 24 and the convex portions 23 and 25 are not necessarily limited to those shown in FIGS. 3 to 5, and for example, as shown in FIGS. 6A, 6B and 6C, respectively. It may have any shape. 6 are external views, the same reference numerals are respectively attached to the portions corresponding to the respective portions of the above-mentioned embodiment, and a concave portion is provided on the input shaft 21 side and a convex portion is provided on the intermediate shaft 18 side. Needless to say, it may be provided.

[0020]

[Effect of device]

 According to the present invention, since the intermediate shaft of the oil pump drive device can be removed together with the oil pump from the engine body, workability at the time of disassembling the engine is improved.

[Brief description of drawings]

FIG. 1 is a diagram showing a conventional oil pump drive device.

FIG. 2 is a cross-sectional view of an engine having an oil pump driving device according to the present invention.

FIG. 3 is a view in which the right side portion of the engine is cut in various cross sections perpendicular to the crankshaft, and a part of each cross section is shown in a fan shape.

FIG. 4 is a sectional view taken along line IV-IV in FIG.

5 is a cross-sectional view taken along the line VV of FIG.

6A and 6B are external views showing various other examples of the coupling portion between the intermediate shaft and the input shaft.

[Explanation of symbols]

1 ... engine, 2 ... crank case, 3 ... transmission case,
4 ... Rear axle, 5 ... Crank shaft, 6 ... Cylinder, 7 ... Scavenging passage, 8 ... Intake port, 9 ... Intake pipe, 10 ... Piston, 11 ... Crank chamber, 12 ... Oil supply hole, 13 ... Main bearing, 14 ... Negative pressure extraction pipe,
15 ... Generator, 16 ... Cooling fan, 17 ... Worm, 18 ... Intermediate shaft, 19 ... Worm gear, 20 ... Oil pump, 21 ... Input shaft, 22 ... Recessed part, 23 ... Convex part, 24 ... Recessed part, 25 ... Convex Department.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoshimi Numazaki 1-4-1 Chuo, Wako, Saitama Stock Company Honda R & D Co., Ltd.

Claims (1)

[Scope of utility model registration request] 1. An oil pump drive device for transmitting a rotational force of a crankshaft of an engine to an input shaft of an oil pump arranged on a side surface of the engine via an intermediate shaft drivingly connected to the crankshaft. In the above, the connecting portion between the intermediate shaft and the input shaft is formed by a concave portion and a convex portion in the axial direction that engage with each other to transmit the rotational force, and a radial direction that further engages with the concave portion and the convex portion. An oil pump drive device characterized in that a concave portion and a convex portion are provided so that the intermediate shaft and the input shaft can be separated in the radial direction but not in the axial direction.