JPS62168910A - Power unit lubricating device for small-sized engine - Google Patents

Abstract

PURPOSE:To reduce the rotating resistance of a speed change gear by providing a pressure releasing hole on an auxiliary tank which is interposed between an oil pump inside an engine case and parts to be lubricated, and communicating the interior of the engine case with the interior of the auxiliary tank, so that the oil level in the engine case can be lowered. CONSTITUTION:An engine case 11 is partitioned into a small chamber as a power transmission chamber 15 and a large chamber via a partition wall 13, and further the large chamber is divided into a crank chamber 19 and a speed change gear chamber 21 via a partition wall 17. On the lower part of the partition wall 13 a penetrating hole 23 is provided to communicate the bottom part of the speed change gear chamber 21 with the bottom part of the power transmission chamber 15. An auxiliary lubricating oil tank 47 is integrally formed inside the speed change gear chamber 21, and the oil pump inside the power transmission chamber 15, after temporarily storing oil in the auxiliary tank 47 via an oil passage 42, supplies it to the parts to be lubricated via oil passages 44. When the pressure inside the auxiliary tank 47 rises, oil is discharged through a pressure releasing pipe 49 so as to be sprayed on speed change gears 41.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] This invention relates to a power unit lubrication system for a small engine.

[Description of prior art]

The conventional dynamic gunnit lubrication system for small engines is
The operation of the oil pump supplies oil from an oil reservoir in the transmission chamber to the oiled parts.

[Problems with conventional technology]

However, in such conventional power unit lubricating devices, the oil reservoir is formed at the bottom of the transmission chamber, and as a result, the operating part of the transmission comes into contact with the liquid level of the oil reservoir, which increases the rotational resistance of the transmission. This has the disadvantage that it has no choice but to increase.

[Means for solving the above problems]

An object of the present invention is to eliminate the above-mentioned disadvantages, and an oil pump is installed in an engine case having an oil reservoir and a transmission chamber, and the lubricating oil in the oil reservoir is supplied by the operation of the oil pump. In the power unit lubricating device, an auxiliary tank is interposed between the oil pump and the lubricated part, and a pressure relief hole is provided in the auxiliary tank, whereby the inside of the auxiliary tank and the engine are provided. This was achieved by communicating with the inside of the case.

[Action of the invention]

Since the power unit lubricating device for a small engine according to the present invention is configured as described above, that is, /fi lubricating oil is temporarily stored in the auxiliary tank, so that it can be stored inside the engine case, that is, in the transmission room. The liquid level in the oil sump is lower than before, and the operating portion of the transmission is moved away from the liquid level in the oil sump, resulting in a reduction in rotational resistance of the transmission.

[Explanation of Examples]

Hereinafter, the present invention will be explained in detail based on FIGS. 1 and 2.

In FIG. 1, 11 is an engine case.

This engine case 11 has a small chamber divided into a power transmission chamber 15 by a partition wall 13, and a large chamber divided into a crank chamber 19 and a transmission chamber 21 by a partition wall 17 (see FIG. 2).

Reference numeral 23 denotes a through hole, which is bored in the lower part of the partition wall 13.

The through hole 23 communicates the bottom of the transmission chamber 21 with the bottom of the power transmission chamber 15, or in other words, extends the oil reservoir O of the transmission chamber 21 to the power transmission chamber 15.

A piston 25 moves back and forth within a cylinder that is integrally formed with the crank chamber 19. Further, 27 is a connecting rod, which connects the piston 25 and the crankshaft 29. The forward and backward movement of the piston 25 is transmitted to the engine shaft 31 as rotational movement by the connecting rod 27 and the crankshaft 29.

33 is a driving gear, which is fixed to the engine shaft 31 protruding into the power transmission chamber 15. This driving gear 33 transmits rotational force to the primary side of a clutch 35 installed in the power transmission chamber 15. 37 is a main shaft of a transmission connected to the secondary side of the clutch 35, and is installed in the transmission chamber 21. Further, 39 is a pair of shafts of the transmission, which is installed in the transmission chamber 21 in parallel with the main shaft 37. This pair of shafts 39 and the main shaft 37 are interlocked by a speed change gear 41 as appropriate.

Next, 43 is an oil pump, which is installed in the power transmission chamber 15. This oil pump 43 is connected to the power transmission chamber 1
The lubricating oil in oil reservoir 0 (see FIG. 1) in 5 is temporarily stored in a lubricating oil tank 47 (described later) through an oil passage 42, and then,
The oil is supplied to the parts to be lubricated (the main shaft 37, the opposite shaft 39, etc. of the transmission) through the oil passage 44. Note that 45 is an intervening gear (see Fig. 1), which controls the rotation of the engine shaft 31 by the oil pump 43.
It is something that can be conveyed to people.

47 is a lubricating oil tank, which is integrally formed within the transmission chamber 21. Further, 49 is a pressure relief pipe corresponding to the pressure relief hole of the present invention, and is fitted onto the upper surface of the lubricating oil tank 47. When the inside of the lubricating oil tank 47 becomes overpressurized, the pressure pipe 49 discharges the lubricating oil so as to spray it onto the speed change gear 41 to adjust the pressure to an appropriate level.

〔Effect of the invention〕

Since the power unit n-slip device for a small engine according to the present invention is configured as described above, the lubricating oil is temporarily stored in the auxiliary tank, so that it can be stored inside the engine case, that is, in the transmission room. As a result of the liquid level in the oil sump being lower than before, even if a relatively large amount of lubricating oil is used, the operating parts of the transmission can be moved away from the liquid level in the oil sump, reducing the rotational resistance of the transmission. .

Also, since the lubricating oil in the oil sump is supplied via an auxiliary tank, compared to conventional dry sump type lubrication, which requires two oil pumps, one for supplying oil and one for returning it to the tank. The structure becomes simpler.

[Brief explanation of drawings]

FIGS. 1 and 2 show an embodiment of the power unit (uniso) fl sliding device for a small engine according to the present invention.
The figure is a longitudinal cross-sectional view, and FIG. 2 is a view showing a main part of a cross section taken along line nn in FIG. 1. ○ ... Oil reservoir 11 ... Engine case 37. 39 ... Lubricated part (37 ... main shaft, 39 ... countershaft) 43 ... Oil pump 47 ... Auxiliary tank 49 ... - Pressure release hole patent applicant: Yamaha Motor Co., Ltd. agent
Patent Attorney Yuji Nosue Pa□゛. Figure 1

Claims (1)

[Claims] (1) A power unit lubricating device in which an oil pump is installed in an engine case having an oil reservoir and a transmission chamber, and the operation of the oil pump supplies lubricating oil from the oil reservoir to an oiled part, An auxiliary tank is interposed between the oil pump and the oiled part, and a pressure relief hole is provided in the auxiliary tank, and the inside of the auxiliary tank and the inside of the engine case are communicated through the pressure relief hole. Power unit lubrication system.