JPH03189450A - Paint structure for v-grooved pulley - Google Patents

Abstract

PURPOSE:To obtain a V-grooved pulley which is excellent in the durability without slipping of a belt and noisy sound from the belt, by applying hard plating paint to an attaching part of a V-grooved pulley for a rotary member, and soft electro-deposition paint to the V-grooved parts of the pulley. CONSTITUTION:For grooves 13 and five grooves 14 are formed at the outer periphery of a V-grooved pulley body 11 on both sides of a median strip 12. First plating paint isapplied to the V-grooved pulley body 11. The layer 20 of plating paint is applied over the entire surface of the V-grooved pulley. Thereafter, the masking is applied to a part of the outer periphery of the body 11, other than the V-grooved part thereof, and then electrodepositing paint is applied thereto. Accordingly, the layer 22 of the electrodepositing paint which is a soft skin layer is formed only on the V-grooved part. With this arrangement, it is possible to prevent peel-off of the paint on the attaching part for a rotary body, and occurrence of fletching, and to ensure a high friction coefficient between V-belts on the V-grooved part so as to prevent slipping of the belts and noisy sound from the belts.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to the coating structure of a ribbed pulley, and in particular,
This invention relates to a V-ribbed pulley attached to the crankshaft of an engine, and an optimal coating structure for use with the ribbed pulley driven from the pulley via a V-belt.

[Prior Art] V-ribbed pulleys are used in various industrial fields, and V-ribbed pulleys made of metal are usually coated with anti-corrosion or anti-wear coating.

For example, FIG. 5 shows a V-rubbed pulley 1 used as a pulley attached to a crankshaft on the front side of an engine and as a pulley for driving auxiliary equipment driven from the crank pulley via a V belt. This V-rubbed pulley 1 is made by processing a metal plate,
On the outer periphery, there is a groove part 3 consisting of four grooves between the median strip 2.
A V-groove portion 4 consisting of five grooves is formed. Reference numeral 5 denotes a mounting part to a rotary body (path shown) that rotationally drives this V-rubbed pulley 1 or is rotationally driven by the V-rubbed pulley 1, and the mounting is fixed with a bolt or the like inserted through bolt 60. . The rubbed pulley 1 is used not as a processed metal plate, but after being coated with anti-rust and wear-resistant paint. Electrodeposition coating is known as a typical anti-rust coating.
Plating coating is known as a typical wear-resistant coating.

[Problems to be Solved by the Invention] However, simply applying electrodeposition coating or plating to the V-ribbed pulley as described above may cause the following problems.

Electrodeposition coating forms a softer surface layer than plating, so if only electrodeposition coating is applied to the entire lipped pulley 1, the repeated force applied to the pulley body, especially at the attachment point to the rotating body, will cause the coating to deteriorate. There is a risk of it peeling off. If the paint on this part peels off, gaps will be created between the mounting bolt seating surface and the pulley body, and between the pulley body and the rotating body, and if the pulley body is used in this state, repeated impact forces will be applied, causing the pulley body to become difficult to install. The surface may be struck and cause fretting.

Since plating can form a harder surface layer than electro-deposition, it can prevent the above-mentioned fretting, but since the friction coefficient of the plating surface is low, ■If the entire ribbed pulley is plated, ■Groove 3.4 and V
There is a problem in that it is difficult to obtain a high coefficient of friction with the belt. Especially for ribbed pulleys used in the front part of the engine, if the coefficient of friction between them and the V-belt is low,
When starting the engine, that is, when the engine speed suddenly increases from a stopped state, a slip occurs at ■bell] ~,
A high-pitched sound occurs (hereinafter also referred to as belt squeal).
There is a risk.

The present invention has focused on these problems, and has as its object (1) to prevent both the peeling off of the coating on the ribbed pulley and the fretting that occurs therefrom, as well as the squealing of the belt due to belt slipping.

[Means for solving the problem] The coating structure of the V-ribbed pulley of the present invention that meets this objective is as follows:
In the painted structure of V-ribbed pulleys made of metal,
At least the surface of the pulley where it is attached to the rotating body is plated, and the surface of the V-groove of the pulley is electroplated.

[Function] By adopting such a coating structure, ■ The groove surface can exhibit a high friction coefficient by electrodeposition coating, and slipping of the V-belt is prevented even when the rotation speed suddenly increases, and the belt The occurrence of squealing is prevented. Since the surface layer of the attachment part to the rotating body is formed by plating, it becomes a hard surface with excellent wear resistance, and the coating does not peel off and fretting is prevented.

[Embodiment 1] A preferred embodiment of the present invention will be described below with reference to the drawings.

1 to 3 show a painted structure of a V-ribbed pulley according to an embodiment of the present invention, and show an application of the present invention to a V-ribbed pulley used in the front part of an automobile engine.

In the figure, 11 indicates the main body of the ribbed pulley.
The ribbed pulley main body 11 is fabricated as a cylindrical pulley with a bottom by processing a metal plate.

■The outer periphery of the ribbed pulley body 11 has four grooves with a central separator 12 in between, similar to the pulley shown in FIG.
Three and five V-grooves 14 are formed. ■The mounting part 15 of the ribbed pulley main body 11 to the rotating body has a reinforcing plate 1
6 is installed. The reinforcing plates 1 to 16 are positioned and fixed to (1) the ribbed pulley main body 11 by (2) fitting the projections 17 from the ribbed pulley main body 11 into the holes 18 on the reinforcing plate 16 side. Note that the present invention may be a V-ribbed pulley without the reinforcing plate 16. (2) The ribbed pulley main body 11 is attached to a rotating body (not shown) by a bolt (not shown) inserted through a bolt hole 19 through this reinforcing plate 16.

■The ribbed pulley main body 11 is first plated with the reinforcing plate 16 fixed.

Therefore, the plating layer 20 is applied over substantially the entire surface of the V-ribbed pulley. However, pulley hole 2
When 1 is the fitting surface with the shaft, it is preferable that this surface is masked and plated to ensure fitting accuracy.

There are various types of plating, but hard chrome plating is suitable for industrial hard plating.

In this example, ■ Ribbed pulley body 1
1. Parts other than the V-groove portion on the outer periphery are masked and electrodeposition coating is applied. Therefore, the electrodeposition coating layer 22 is:
Formed only in the groove. Electrodeposition coating is known as a coating method that can form a softer surface layer than plating or the like. In this embodiment, cationic coating was used as the electrodeposition coating, but anion coating may also be used.

In the coated V-ribbed pulley as described above, the surface of the V-groove is composed of a soft electrodeposited coating layer 22 with a low coefficient of friction, ensuring a high coefficient of friction between the belt and the belt. This prevents the belt from slipping. Therefore, even when the V-ribbed pulley employed in the front part of the engine suddenly increases its rotational speed, such as when starting the engine, it does not slip to the bell 1, and the occurrence of belt squeal is prevented.

Further, since the surface of the mounting surface to a rotating body such as a crankshaft or an auxiliary machinery shaft is formed with the plating layer 20, high wear resistance is ensured. As a result, peeling of the paint is prevented, and fretting caused by peeling of the paint is also prevented, ensuring high wear resistance on this surface and high durability of the pulley as a whole.

In the above embodiments, (1) the groove portions are coated with electrodeposition coating, but (2) the groove portions may be coated with only electrodeposition coating. That is, as shown in FIG. 4, the V-groove portion 3 of the V-ribbed pulley body 31 is
2 with a masking jig and apply plating to areas other than the V-groove, then cover the plated area with a masking jig and apply electrodeposition coating (34) (for example, cationic coating) to the V-groove 32.

Even with such a coating structure, basically the same functions and effects as those of the above-mentioned embodiments can be obtained.

[Effects of the Invention] As explained above, when using the coating structure of the V-ribbed pulley of the present invention, at least the attachment part of the V-ribbed pulley to the rotating body is coated with a hard plating coating, and the groove part is coated with a soft coating with a coefficient of friction. Since the electrodeposited coating has a high viscosity, it is possible to prevent the coating from peeling off at the attachment part to the rotating body and prevent fretting, and also to increase the coefficient of friction between the groove part and the belt. This can prevent belt slippage and belt squeal. Therefore, it is possible to obtain a ribbed pulley which is excellent in durability, does not cause belt slip or belt squeal, and has a suitable R for use in engine front parts, etc.

[Brief Description of the Drawings] Fig. 1 is a sectional view of a ribbed pulley according to an embodiment of the present invention, Fig. 2 is a side view of the ribbed pulley of Fig. 1, and Fig. 3 is a side view of the V-ribbed pulley of Fig. 1. FIG. 4 is an enlarged partial cross-sectional view of a ribbed pulley according to another embodiment of the present invention; FIG. 5 is a cross-sectional view of a conventional ribbed pulley. 11.31...■ Ribbed pulley body 13.14
．． 32...■Groove 15...Mounting part 16 to the rotating body...Reinforcement play 1-19...Bolt hole 20.33...・Layer of plating paint 22.34...
・・・・Layer of electrodeposition coating

Claims (1)

[Claims] 1. A painted structure of a V-ribbed pulley made of metal, characterized in that at least the surface of the pulley where it is attached to the rotating body is plated, and the surface of the V-groove of the pulley is electroplated. Painted structure of V-ribbed pulley.