JPS5922243Y2 - engine offset tappet - Google Patents

Description

[Detailed Description of the Invention] This invention relates to an engine offset that reduces uneven wear on the contact surface of the tappet by offsetting the engine tappet with respect to the valve operating cam.

Conventionally, in order to avoid uneven wear on the contact surface of the tappet, the center axis of the tappet and the center line of the valve drive cam are slightly offset, and the tappet is rotated gently as the valve drive cam rotates. However, in this case, the rotational movement due to the offset cannot overcome the rotational resistance of the tappet, such as the frictional force generated between the tappet and its sliding hole, and despite the offset, Tappets may not rotate.

This invention has a lubricating oil blowing hole opened in the tappet sliding hole of the offset tappet as described above in a tangential manner to the circumferential surface of the tappet, and a pressure receiving surface is provided on the outer circumferential surface of the tappet corresponding to the lubricating oil blowing hole. A concave portion is formed so that the tappet can be reliably rotated in the offset rotation direction with the help of lubricating oil blown out from this hole.

Hereinafter, the embodiments of this invention will be explained based on the drawings.
The figure shows a pressure-feeding lubrication system for an overhead valve type V-type engine.
The lubricating oil stored in is filtered by an oil strainer 3, pumped by an oil pump 4, passed through a relief valve 5, an oil filter 6, and then supplied to the crankshaft 7, valve drive camshaft 8, and left and right double-ended hook arms. The passage 10 to the double-ended lubricant arm 9 has a branched lubricating oil blowing hole 13 toward the sliding hole 12 of the tappet 11 on the way.

The lubricating oil blowout hole 13 is opened on the peripheral wall of the tappet sliding hole 12 in a tangential manner to the tappet 11, and the opening is in the form of a long groove with an open end.

As shown in FIG. 3, the tappet 11 is an offset tappet in which its center axis X is slightly offset from the center line y in the width direction of the valve drive cam 14 that carries the valve drive power. A spherical seat surface 16 for connection with a bushing rod 15 is formed on the inner bottom surface of the cylindrical tappet body.

Further, an inclined groove 18 is spirally carved on the outer circumferential surface 17 of the tappet 11, and as shown in FIG. It is a notch groove having an inclined pressure receiving surface 19 for stopping.

Next, to explain the operation of the above configuration, the rotation of the camshaft 8 applies a rotational moment to the tappet 11 in the direction of the arrow a due to an offset, while the lubricating oil pumped from the oil pump 4 is forced into the lubricating oil outlet. Through hole 13,
The air is blown perpendicularly to the pressure receiving surface 19 of the inclined groove 18 of the tappet 11, and the resulting rotational moment is added to the rotational moment due to the offset, causing the tappet 11 to rotate gently in the direction of arrow a.

A large number of wedge-shaped notched recesses 18 having pressure receiving surfaces 19 that directly receive the lubricating oil blowing out from the lubricating oil blowing holes 13 are arranged in parallel on a portion of the outer peripheral surface 17 of the tappet corresponding to the lubricating oil blowing holes 13.

As detailed above, this invention has a lubricating oil blowing hole in the tappet sliding hole that opens tangentially to the tappet in the same direction as the rotational direction due to the offset of the tappet. Since a recess with a pressure-receiving surface is formed on the outer circumferential surface of the tappet corresponding to the outlet hole, the lubricating oil blown out from the lubricant outlet collides with the tappet tangentially, causing the tappet to rotate in the same direction as the offset rotation direction. Force rotation.

Thereby, the tappet can be rotated reliably, and uneven wear on the contact surface of the tappet can be reliably reduced.

In addition, for this purpose, the lubricating oil pressure of the engine is used to
Although it is only necessary to make a lubricant outlet hole, the structure is simple and can be implemented at low cost.

[Brief explanation of drawings]

The drawings show an embodiment of an offset tappet for an engine according to this invention, and FIG. 1 is a schematic front view showing a pressure-feeding lubrication system for an overhead valve type ■ type engine, and FIG. 2 is a longitudinal sectional front view of section A in FIG. 3 is a sectional view taken along the line B--B in FIG. 2, FIG. 4 is a partially cutaway perspective view of the tappet, and FIG. 5 is a view corresponding to FIG. 4 showing another embodiment. 11... Tappet, 12... Tappet sliding hole, 13... Lubricating oil outlet hole, 17...
... 11 outer peripheral surface, 18 ... inclined groove, notch recess, 19 ... pressure receiving surface.

Claims (1)

[Scope of utility model registration request] 1. In an offset tappet in which the axis X of the tappet 11 and the center line y in the width direction of the valve drive cam 14 are offset, a lubricating oil blowout hole 13 is provided in the tappet sliding hole 12,
A recess 18 is formed on the tappet outer circumferential surface 17 corresponding to the lubricating oil blowing hole 13 and having a pressure receiving surface 19, which opens tangentially to the tappet 11 and blows out lubricating oil in the same direction as the rotational direction due to the offset of the tappet 11. The engine's offset tappet is characterized by: 2. The engine offset according to claim 1, wherein the recesses 18 formed in the tappet outer circumferential surface 17 are wedge-shaped cutout recesses provided at appropriate intervals in the circumferential direction of the tappet. Tappet. 3. The offset tappet for an engine according to claim 1, wherein the recess 18 formed on the outer peripheral surface 17 of the tappet is formed by a groove inclined in the circumferential direction of the tappet.