JPS5911222Y2 - Internal combustion engine balancer drive device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement of a balancer drive device for driving a balancer for removing unbalanced inertial force generated in the crankshaft of an internal combustion engine.

Conventionally, as a balancer drive device for this type of internal combustion engine, there has been a balancer that is pivotally supported by a cylinder block and removes the unbalanced inertia force of the crankshaft, a balancer gear fixed to an end of the balancer, and an idler gear that meshes with the balancer gear. , an idler pulley fixed to the shaft of the idler gear, and the rotation of the crankshaft is transmitted to the idler pulley, the idler gear, and the balancer gear via a timing belt or timing chain to drive the balancer. This is known (see Japanese Patent Laid-Open No. 51-55836).

By the way, in the balancer drive device as described above, when the idler gear that engages with the balancer gear is supported in a cantilevered manner on the cylinder block wall, the mechanical strength is reduced due to the provision of the idler pulley on the free end side of the idler gear shaft. Problems arise in terms of vibration.

Therefore, the idle gear and balancer gear are covered with a balancer cover fixed to the cylinder block wall, one end of the idle gear shaft is pivotally supported on the cylinder block wall, and the other end is pivotally supported by the cover, and It is necessary to place an idler pulley outside the cover.

However, when the balancer is rotated at the same speed or double the speed of the crankshaft in such a configuration, the idle gear shaft also rotates at high speed, which may cause problems such as seizure of the idle gear shaft, which is supported by the balancer cover. was occurring.

Therefore, in view of this point, the present invention has been proposed in such a case that the idle gear that engages with the balancer gear is supported by the cylinder block and the balancer cover so as to be supported at both ends. It is an object of the present invention to provide a balancer drive device for an internal combustion engine that can supply oil for lubrication between the two with simple precautions.

That is, in the present invention, an oil passage for lubricating the bearing portion of the balancer cover is provided in the shaft of the idle gear, and the oil passage is concentrically connected to the main oil gallery of the cylinder block. .

Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings.

In FIGS. 1 and 2, 1 is a cylinder block of an internal combustion engine, 2 is a crankshaft rotatably supported by the cylinder block 1, and 3 is a crankshaft fin provided at the shaft end of the crankshaft 2. 4 is rotatably attached to the cylinder block 1 and connected to the crankshaft 2.
5 is a camshaft pulley provided at the shaft end of the camshaft 4; 6 is a water pump pulley provided at the shaft end of a water pump (not shown); It also serves as a tensioner for the timing belt 13, which will be described later.

A balancer 7 is rotatably supported in the cylinder block 1 and parallel to the crankshaft 2, and is for removing unbalanced inertia of the crankshaft 2. A balancer gear 8 is fixed by bolts 9, an idler gear 10 is directly engaged with the balancer gear 8, an idler pulley 12 is fixed to the end of the shaft 11 of the idler gear 10, and the idler gear 12, A timing belt 13 is wound around the crankshaft pulley 3, camshaft pulley 5, and water pump pulley 6, and 20 rotations of the crankshaft are passed through the timing belt 13 to the idler pulley 12 and the idler gear. 10 and balance sagya 8
The balancer 7 is rotated at the same speed as the crankshaft 2 in the opposite direction, and the camshaft 4 and the water pump are also rotationally driven.

Further, 14 is an oil pump driven by the crankshaft 2, and 15 is a main oil gallery provided in the cylinder block 1, to which lubricating oil pumped from the oil pump 14 is supplied. It is branched and supplied to the crankshaft 2, camshaft 4, etc. to lubricate each part.

And 16 is the above balancer gya 8 and idol gya 10
The balancer cover 16 is fixed to the end wall 1a of the cylinder block 1 by a bone plate 17.

Inside the balancer cover 16, one end 11a of the shaft 11 of the idle gear 10 is connected to the cylinder block 1.
The other end 11b is rotatably supported in a bearing recess 18 formed in the end wall 1a of the cover 16, while the other end 11b is rotatably supported in a bearing 19 provided in the cover 16.
b protrudes outward from the cover 16, and the idle pulley 12 is fixed to the protruding portion, and the idle pulley 12 is disposed outside the cover 16.

Furthermore, inside the shaft 11 of the idle gear 10, the shaft 1
The main oil gallery 15 is opened in the end wall 1a of the cylinder block 1 in which the bearing recess 18 is provided. The oil passage 20 and the main oil gallery 15 are concentrically connected, and the oil passage 2 is connected from the main oil gallery 15 to the main oil gallery 15.
lubricating oil is supplied to 0.

Further, an oil passage 2 is provided in the shaft 11 of the idle gear 10.
A branch passage 21 branching in the radial direction from the shaft 11 toward the bearing portion 19 of the cover 16 is bored, and an outer circumferential groove 22 . 22, the lubricating oil supplied to the oil passage 20 is evenly supplied to the bearing part 19 of the cover 16 through the branch passage 21 and the outer circumferential groove 22.22. The cover 16 and the side surfaces of the idle gear 10 are also lubricated.

Incidentally, reference numeral 23 indicates an oil hole drilled in the cover 16 so as to supply the lubricating oil supplied to the bearing portion 19 to the meshing portion between the idler gear 10 and the balancer gear 8, etc., and 24 indicates an oil hole branched from the main oil gallery 15. , a branch passage for supplying lubricating oil to the shaft portion of the balancer 7.

Further, 25 is an oil drain hole, 26 is a thrust plate, and 27 is a timing force bar for covering the timing belt 13.

Therefore, in the above embodiment, the idle gear 10 to which the idle pulley 12 is fixed to the shaft end (the other end 11b of the shaft 11) is covered with the balancer cover 16, and one end of the shaft 11 of the idle gear 10 is covered with the balancer cover 16. By having the portion 11a pivoted in a bearing recess 18 provided in the end wall 1a of the cylinder block 1, and the other end 11b being pivoted in a bearing portion 19 provided in the force bar 16, the idle gear 10 is supported at both ends. It is supported by a shaft like a support, and can ensure sufficient mechanical strength against the transmission tension of the timing belt 13, and does not cause deflection or vibration of the shaft 11.

Moreover, since lubricating oil from the main oil gallery 15 is supplied to the bearing portion 19 of the cover 16 via the oil passage 20, the branch passage 21, and the outer circumferential groove 22, the bearing portion 19 can be sufficiently lubricated. I can do it.

In addition, the main oil gallery 15 is located in the bearing recess 18.
The lubricating oil is supplied by the bearing recess 18, and the bearing recess 18 can be sufficiently lubricated.

Further, the lubricating oil supplied to the bearing portion 19 can also lubricate the meshing portion between the idler gear 10 and the balancer gear through the oil hole 23.

The main oil gallery 15 is normally machined to penetrate the cylinder block 1 in the longitudinal direction, and a pride plug is required at the open end of the main oil gallery 15. The concentric connection of the passages 20 also has the advantage that the pride plug described above is unnecessary.

In the above embodiment, the rotational force of the crankshaft 2 is transmitted to the idler pulley 12 via the timing belt 13, but it goes without saying that a timing chain may be used instead of the timing belt 13.

As explained above, according to the present invention, when the idler gear that engages with the balancer gear is pivotally supported by the cylinder block and the balancer cover so that both ends are supported, an oil passage is formed inside the shaft of the idler gear. established,
With a simple structure in which the oil passage is concentrically connected to the oil passage (main oil gallery) formed in the cylinder block, sufficient lubrication can be achieved between the balancer cover and the idle gear. This also has the advantage that the conventionally required pride plug at the open end of the main oil gallery can be omitted.

[Brief explanation of the drawing]

The drawings illustrate an embodiment of the present invention, and FIG. 1 is an overall schematic view, and FIG. 2 is a longitudinal cross-sectional view of a main part. 1... Cylinder block, 1a... End wall, 2... Crankshaft, 3...
・Crankshaft field, 4...camshaft, 5...camshaft pulley, 6...
...Water pump pulley, 7...Balancer,
8...Balance Gya, 9...Bolt,
10...Idol Gya, 11...Axis,
11 a... One end, 1l b... Other end, 12... Idle pulley, 13...
...Timing belt, 14...Oil pump, 15...Main oil gallery, 16...
... Balancer cover 17 ... Bolt, 18
...Bearing recess, 19 ...Bearing part, 20
...Oil passage, 21... Branch passage,
22...Outer circumferential groove, 23...Oil hole,
24... Branch passage, 25... Oil drain hole,
26... Thrust plate, 27...
timing force bar

Claims (1)

[Scope of utility model registration request] A balancer that is pivotally supported by a cylinder block and removes unbalanced inertia of the crankshaft, a balancer gear fixed to the end of the balancer, an idler gear that meshes with the balancer gear, and an idler pulley fixed to the shaft of the idler gear. In the balancer drive device for an internal combustion engine, the balancer drive device for an internal combustion engine is configured to drive the balancer by transmitting the rotation of the crankshaft to an idle pulley, an idle gear, and a balancer gear via a timing belt or a timing chain. is covered with a balancer cover fixed to the cylinder block wall, one end of the idle gear shaft is pivotally supported on the cylinder block wall, and the other end is pivotally supported on the cover, and the idle gear shaft is mounted on the outside of the cover. The engine is characterized in that an oil passage is provided inside the idle gear shaft and opens on one end side, and the oil passage is connected to an oil passage that is provided in the cylinder block and opens in the cylinder block wall. Balancer drive device for internal combustion engines.