JPS62107219A - Oil pump driving device for engine - Google Patents

Abstract

PURPOSE:To prevent the load due to the driving of a balancer shaft from acting on an oil pump by driving the balancer shaft on one side to one direction via an idle gear by means of a power transmission member, and driving directly the balancer shaft on the other side to the other direction respectively. CONSTITUTION:When a crankshaft 17 is turned, respective upper and lower stage sprockets 22 and 21 are driven. And a camshaft 33 is driven by the first chain 35 interlocked with the lower stage sprocket 21 via a sprocket 34. On the other hand, an idle gear 24 is driven by the second chain 38 interlocked with the upper stage sprocket 22 via a sprocket 25, and the left balancer shaft 18 is driven in the counterclockwise direction via a drive gear 23 which is engaged with the idle gear 24, and at the same time the right balancer shaft 19 is driven in the clockwise direction via a sprocket 27. Furthermore, a pump shaft 29 is driven via a pump gear 28 which is engaged with a drive gear 26.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an improvement of an Ennon oil pump drive device.

(Prior art) Conventionally, as an engine oil pump drive device, tJ
As shown in Figure tJ3, sprocket 2 of crankshaft 1 and sprocket 4 of one balancer shaft 3
A chain 7 is stretched between the sprocket 6 of the oil pump 5, and a gear 8 integrated with the sprocket 6 of the oil pump 5 and a gear 10 of the other balancer shaft 9 are meshed with each other to prevent the rotation of the crankshaft 1. , one balancer shaft 3 is driven clockwise in the figure via the chain 7, while the oil pump 5 is driven by the chain 7, and the other balancer shaft 9 is driven counterclockwise in the figure via the oil pump 5. A system has been proposed in which the motor is driven in a similar manner (see Japanese Utility Model Publication No. 58-13166).

However, since the other balancer shaft 9 is driven through the oil pump 5, a load due to oil discharge and a load due to driving the balancer shaft act on the gear 8 of the oil pump 5 and the pump shaft at the same time. Therefore, there was a problem that the durability decreased.

(Purpose of the Invention) The present invention has been made to solve the above-mentioned conventional problems, and it improves the oil pump drive system by reducing the load on the oil pump gears and pump shaft. The purpose is to improve durability.

(Structure of the Invention) Therefore, in an engine in which two balancer shafts each having a balance weight are driven in reverse by a crankshaft 7Y, the present invention transmits the rotation of the crankshaft Y to each balancer shaft 7F. A power transmission member is provided, one balancer shaft is driven via an idle gear driven by the power transmission member, the other balancer shaft is directly driven by the power transmission member, and the power transmission member The oil pump is characterized in that the oil pump is driven through a gear of a balancer shaft that is directly driven by the balancer shaft.

(Effects of the Invention) According to the present invention, the power transmission member drives one balancer shaft in one direction via the idle gear, directly drives the other balancer shaft in its own rotation, and Since the oil pump is driven through the balancer shaft gear, the load from the balancer shaft drive is no longer applied to the oil pump gear and pump shaft, improving their durability. Become.

(Embodiments) Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

As shown in FIGS. 1 and 2, a crankshaft 17 is disposed at the center of the cylinder block 16 of the engine 15 and is driven clockwise in the drawings by the pistons of the engine 15. One balancer shaft 18 having a balance weight 18a is arranged at the center left position, and a balancer shaft 18 is arranged at the right position in the figure.
The other balancer shaft 19 with 9a is arranged.

The crankshaft 17 has a lower sprocket 21
and the upper stage sprocket 22 are coaxially attached.

A drive gear 23 is attached to the left balancer shaft 18, and an idle gear 24 that meshes with the drive gear 23 and a sprocket 25 that opposes the upper sprocket 22 are coaxially disposed above the left balancer shaft 18. It is located.

A drive gear 26 and a sprocket 27 opposing the large-diameter sprocket 22 are coaxially attached to the right balancer shaft 19, and a pump gear meshing with the drive gear 26 is installed at a lower position of the right balancer shaft 19. An oil pump 30 having a pump 28 supported by a pump shaft 29 is disposed.

The oil pump 30 includes a suction pipe 31a and a discharge pipe 311.
) are connected.

The cylinder head 32 mounted on the upper part of the cylinder block 16 has a camshaft 33 that drives the intake and exhaust valves.
A sprocket 34 facing the lower sprocket 21 of the crankshaft 17 is attached to the camshaft 33.

And crank shirt) 17 lower sprocket 21
and the sprocket 34 of the camshaft 33,
A first endless chain 35 is tensioned, and tension members 36 and 37 are attached to the first endless chain 35.
is provided.

Furthermore, a second endless chain 38 is stretched between the upper sprocket 22 of the crankshaft 17, the sprocket 25 of the idle gear 24, and the sprocket 27 of one right balancer shaft. Tension member 39140.4
1 is provided.

The side surfaces of the cylinder block 16 and the cylinder head 32 are closed with a cover 43.

With the above configuration, the upper and lower sprockets 22 and 21 are driven by the rotation of the crankshaft 17, and the camshaft 33 is driven via the sprocket 34 by the first endless chain 35 interlocking with the lower sprocket 21. On the other hand, the idler gear 24 is driven by the second endless chain 38 interlocked with the upper stage sprocket 21 via the sprocket 25, and the left balancer shaft 18 is moved to the left in the figure via the drive gear 23 meshing with the idler gear 24. At the same time, the right balancer shaft 19 is driven clockwise in the figure via the sprocket 27.

Further, the pump shaft 29 is also driven via the pump gear 28 that meshes with the drive gear 26.

Therefore, the second endless chain 38 causes the left balancer shaft 18 to rotate counterclockwise via the idle gear 24.
The right balancer shaft 19 will be driven directly clockwise, and the two pump shafts will be driven clockwise.
Since the right balancer shaft 19 is driven via the drive gear 26, the load caused by driving the right balancer shaft 19 does not act on the pump gear 28 or the two pump shafts.

[Brief explanation of drawings]

FIG. 1 is a side view of an engine equipped with an oil pump drive device according to the present invention, FIG. 2 is an enlarged sectional view taken along line I-■ in FIG.
FIG. 3 is a side view of a conventional oil pump drive device. 15...Engine, 17...Crankshaft, 1
8.19... Balancer shaft, 18a, 19a... Balance weight, 21.22,
25.27... Sprocket, 23.26... Drive gear, 24... Idle gear, 28... Pump gear,
29...Pump shaft, 30...Oil pump,
38...Second endless chain.

Claims (1)

[Claims] (1) In an engine in which two balancer shafts each having a balance weight are driven to rotate in opposite directions by a crankshaft, a power transmission member is provided that transmits the rotation of the crankshaft to each balancer shaft, One balancer shaft is driven via an idle gear driven by the power transmission member, the other balancer shaft is directly driven by the power transmission member, and a balancer shaft is driven directly by the power transmission member. An oil pump drive device for an engine, characterized in that the oil pump is configured to be driven through a gear.