JPH1078114A - Aluminum pulley and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress cost and meet requirement such that an abrasion amount is 500 micrometers or less at a target life of a pulley by combinating an abrasion resistant plating layer thicker than a conventional one with an original pulley material. SOLUTION: An abrasion resistant plating 18 having thickness ranging between 100 and 500 micrometers is applied into a belt groove 12 of an aluminum pulley 11 obtained by casting an aluminum alloy. Combination of kinds of material of the aluminum alloy with thickness of the abrasion resistant plating can be selected according to specifications, etc., of an engine. It is possible to meet requirement of an abrasion rate of 500 micrometers or less at a target life D of the pulley. It is also possible to elongate life by applying the plating again into the belt groove by removing the pulley before the plating layer is eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an aluminum pulley used for, for example, a crank pulley of an engine and a method of manufacturing the same.

[0002]

2. Description of the Related Art A V-shaped groove is formed on the outer periphery of an engine or the like, and a pulley driven by a so-called V-belt is used in the V-shaped groove.
It is required that the weight of the engine be reduced as much as possible. For this reason, attempts have been made to change the pulley from aluminum to aluminum. In this case, as a material, Al-Si- for casting in Japanese Industrial Standard (JIS) H5202 is used.
AC4A, AC4C which is a Mg-based aluminum alloy with good castability, mechanical properties or corrosion resistance, and Japanese Industrial Standards (JI
S) Al-Si-C for die casting in H5302
ADC12 which is a u-based aluminum alloy with good castability, machinability and mechanical properties, and also Al-Si-C for die casting
In the u-based aluminum alloy, ADC14 excellent in wear resistance and a high silicon aluminum casting similar thereto were selected, and at the time of casting or die-casting, after performing a solution treatment called T6, an artificial aging hardening treatment was performed. AC4A-T6, A
C4C-T6 and high silicon aluminum casting-T6 are used.

As shown in FIG. 4, the pulley 1 has a V-belt 3 fitted in a V-shaped belt groove 2 formed on the outer periphery thereof, while applying a pressing force in the direction of an arrow, in a direction perpendicular to the paper surface. When moving, the side surface 3a is slid while being pressed against the opposed inclined wall (sliding surface) 2a of the V-shaped belt groove 2, and is rotated. Therefore, if the above state is continued for a long time, the opposed inclined wall (sliding surface) 2a of the V-shaped belt groove 2 is worn, and according to the study of the present inventors, this wear amount S is 50%.
When it reaches 0 to 600 μm, as shown in FIG. 5, only the both sides of the worn portion come into contact with the side surface 3a of the V-belt 3, and the surface pressure on the side surface 3a is increased as indicated by a dotted line, and the side surface 3a is significantly worn in a short time. At least, it was found that the V belt 3 became unusable in a short time.

[0004] Opposed inclined wall (sliding surface) of the V-shaped belt groove 2
Naturally, the wear amount S of 2a differs depending on the material, but this will be described with reference to FIG. FIG. 3 is a pulley wear curve diagram in which the horizontal axis represents time H and the vertical axis represents the wear amount μm, and the horizontal axis represents time, for example, as a target life D of the pulley, for example, a vehicle traveling distance of 700,000 km is converted to time. The values between 0 and D are divided into A = 200,000 km, B = 400,000 km, and C = 600,000 km by time-converted values. Although the wear amount on the vertical axis is indicated by a high numerical value, from the standpoint of safety, the wear amount is required to be 500 μm or less even in the case of D. Therefore, the horizontal line of 500 μm can be said to be an allowable wear limit line. In the wear curve diagram of this pulley,
Is made of AC4A-T6, is made of ADC12, and is made of AC
4C-T6, ADC14, high silicon aluminum casting-T6, and cast iron pulley wear curves. As will be understood from this figure, the pulleys made of the above-mentioned materials cannot satisfy the requirement that "the wear amount is 500 μm or less even in the case of D" except for the above.

In order to reduce the abrasion amount by subjecting the V-shaped belt groove 2 to a surface hardening treatment, an electroplating method which is excellent in abrasion resistance and inexpensive among the surface hardening methods is used. It is conceivable to apply. However, according to the study of the present inventor, dust floating in the air is 5 times.
直径 80 μm, and the main component is SiO 2
_{2. Since} it is an aggregate of oxides having high hardness such as Al ₂ O ₃ and Fe ₂ O ₃ , if the electroplating is made to have a thickness of about 50 μm in order to suppress the cost, the plating layer is It has been found that sliding with the belt causes abnormal wear that is deeply pierced by large dust particles and accelerates wear. However, making the plating layer extremely thick and dealing with dust and abrasion using only this plating layer has a problem that the plating cost becomes too high.

As a result of the above research, the present inventor has found that a thicker than normal wear-resistant plating which is not deeply pierced by the large dust particles and causes abnormal wear is formed in the V-shaped belt groove of the aluminum pulley. However, the above-mentioned requirement that the wear amount at the target life D of the pulley be reduced to 500 μm or less while suppressing the cost by combining the plating layer and the original pulley material, instead of responding to dust and abrasion with only this thick plating layer. I was able to respond to.

[0007]

That is, the problem to be solved by the present invention is that the combination of the thicker wear-resistant plating layer and the original pulley material can reduce the cost and reduce the target life D of the pulley. An object of the present invention is to provide an aluminum pulley and a method for manufacturing the same, which meet the above-mentioned requirement to reduce the wear amount to 500 μm or less.

[0008]

According to the present invention, there is provided an aluminum pulley obtained by casting an aluminum alloy, the belt groove of which is provided with a wear-resistant plating having a thickness of 100 μm or more and 500 μm or less. An invention relating to an aluminum pulley, characterized in that a belt groove of an aluminum pulley obtained by casting an aluminum alloy is formed in consideration of a plating thickness, and a belt having a thickness of 100 μm or more and 500 μm or less is formed in the belt groove. The invention relates to a method for manufacturing an aluminum pulley, which is characterized by applying wear plating.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail with reference to FIGS. 1 and 2, 11
Is an aluminum pulley according to the present invention.
A cylindrical portion 13 having a belt-shaped groove 12 is formed at one end thereof integrally with a mounting disk portion 14. The disk portion 14 has, for example, a female screw 15 for mounting a damper and a female screw 15 for mounting to a crankshaft. Bolt holes 16 and cast holes 17 for weight reduction are formed. In the V-shaped belt groove portion 12, a wear-resistant plating layer 18 is formed on the opposed inclined wall 12a and the bottom surface 12b, and serves as a sliding surface 12c. The plating layer 18 has a thickness of 100 μm or more depending on the material of the pulley 11.
The thickness is selected within the range of 00 μm or less.

When the aluminum pulley 11 of the present invention is manufactured, the material of the AC4A-T6, AC4C
-T6, high silicon aluminum casting with 14 to 16% Si-
T6 or the like is selected, this is formed as a rough material by gravity casting or die casting, and is formed into a shape as shown in FIG. 1 by machining. At this time, in forming the V-shaped belt groove portion 12, particularly, the opposed inclined wall 12a, if necessary, the V-shaped belt groove portion 12 may be cut in accordance with the thickness of the wear-resistant plating layer 18. After such processing, a plating layer 18 having a thickness of 100 to 170 μm is formed on the V-shaped groove 12 by hard electroplating or the like to form a sliding surface 12c.
In FIG. 3, AC4A-T6 is coated with abrasion-resistant plating to a thickness of 170 μm, and AC4C-T6 is used.
Respectively, and the above-mentioned plating is applied to a thickness of 150 μm, or the 14 to 16% high silicon aluminum casting-T6 is applied to the plating with a thickness of 100 μm.

In the aluminum pulley 11 of the present invention formed as described above, as shown in FIG. 2, the sliding surface 12c of the V-shaped belt groove 12 slides with the V-belt 3 hung thereon,
First, the plating layer 18 is worn. Since the plating layer 18 has a thickness of 100 μm or more, the resistance to dust is large. Even if the particle size of the dust is as large as 80 μm as described above, abnormal wear such as deep burring does not occur. Without producing it,
As shown by the lines, the plating layer 18 alone corresponds to the wear up to the time converted from the time of 550,000 km, 500,000 km, and 330,000 km, respectively.

After the plating layer 18 has disappeared, the base metal of the aluminum pulley 11 resists abrasion, and as shown in FIG. In the case of D, the wear is completed at 400 μm. Therefore, the function of the aluminum pulley 11 can be safely terminated with a sufficient wear value within the allowable wear limit of 500 μm.

[0013]

The aluminum pulley of the present invention has a belt groove of 10 mm in an aluminum pulley obtained by casting an aluminum alloy.
Since it is characterized by being provided with a wear-resistant plating having a thickness of 0 μm or more and 500 μm or less, it is not only lightweight,
Abrasion-resistant plating with a film thickness of 100 μm or more does not cause the plating layer to be deeply pierced even by dust having a large particle size, and is at least approximately の of the time until the life of the pulley.
, And the remaining time can be handled with sufficient margin using the pulley metal.

Further, in the method of manufacturing an aluminum pulley according to the present invention, a belt groove of an aluminum pulley obtained by casting an aluminum alloy is formed in consideration of a plating thickness, and the belt groove is formed in a thickness of 100 μm or more and 500 μm or less. In addition to providing a pulley made of aluminum which meets the requirement of reducing the amount of wear at the target life D of the pulley to 500 μm or less while suppressing costs, the engine is characterized in that According to the above requirements, it is possible to adjust the combination of the type of the base metal of the aluminum pulley and the thickness of the wear-resistant plating according to the specifications of the pulley, and to reduce the wear amount at the target life D of the pulley to 500 μm or less while suppressing the cost. Has the effect. Further, according to the present invention, it is possible to extend the life by removing the pulley and replating the belt groove before the plating layer disappears.

[Brief description of the drawings]

FIG. 1 is a front view showing a cross section of an upper half of an aluminum pulley according to the present invention.

FIG. 2 is an enlarged sectional view showing the vicinity of a belt groove of the aluminum pulley of the present invention together with a V-belt.

FIG. 3 is a wear curve diagram of an aluminum pulley.

FIG. 4 is a sectional view showing a relationship between a V-belt and a belt groove in a new conventional aluminum pulley.

FIG. 5 is an enlarged sectional view showing a state in which a conventional aluminum pulley is worn by a V-belt.

[Explanation of symbols]

1 Conventional aluminum pulley 2 V-shaped belt groove 2
a Opposed inclined wall (sliding surface) 3 V belt 3a Side surface of belt S Wear amount 11 Aluminum pulley of the present invention 12 V-shaped belt groove 13 Cylindrical part 14 Mounting disk part 15 Damper mounting female screw 16 Bolt hole 17 Casting Drilled hole 18 Wear-resistant plating layer.

Claims (5)

[Claims] 1. An aluminum pulley, wherein a belt groove of an aluminum pulley obtained by casting an aluminum alloy is provided with a wear-resistant plating having a thickness of 100 μm or more and 500 μm or less. 2. A belt groove of an aluminum pulley obtained by casting an aluminum alloy is formed in consideration of a plating thickness, and the belt groove is provided with wear-resistant plating having a thickness of 100 μm or more and 500 μm or less. Characteristic method of manufacturing aluminum pulleys. 3. The method according to claim 1, wherein said aluminum alloy is Si14-16.
The method for producing an aluminum pulley according to claim 2, wherein the aluminum pulley is an aluminum alloy casting or an aluminum alloy die-cast containing a weight percent, and a solution aging treatment and an artificial aging hardening treatment are performed before the plating treatment. 4. The aluminum alloy according to claim 1, wherein said aluminum alloy is an aluminum alloy casting to which Japanese Industrial Standards (JIS) H5202 is applied, and is subjected to a solution aging treatment and then an artificial age hardening treatment before said plating treatment. Item 3. A method for producing an aluminum pulley according to Item 2. 5. The method according to claim 1, wherein the aluminum alloy is an aluminum alloy die-cast to which Japanese Industrial Standard (JIS) H5302 is applied, and a solution aging treatment and an artificial aging hardening treatment are performed before the plating treatment. Item 3. A method for producing an aluminum pulley according to Item 2.