JPH0647205B2 - V-ribbed belt manufacturing method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for manufacturing a V-ribbed belt, and relates to
The present invention relates to an improved method of manufacturing a V-ribbed belt by forming grooves by cutting.

[Conventional technology]

Conventionally, when manufacturing a V-ribbed belt in which a plurality of V-grooves are provided in parallel on the inner peripheral surface of the belt, a large number of V-grooves are cut and formed in parallel on the outer surface of a cylindrical mold preliminarily molded from an elastomer material. It is performed that a processed cylindrical element is cut into a ring shape with a predetermined width and inverted to obtain a product.

In this cutting process, conventionally, a rough finish grinding machine is first used to form a rough groove shape, and then a finish grinding machine is used to finish the bottom and side surfaces of the groove.

The reason why the V-groove is shaped by such a two-step process is that when the V-groove is formed only by the finish grinder, it takes a long time to grind due to the fineness of the abrasive grains, and the heat generated during that time causes the elastomer material to be melted. It causes clogging, and on the other hand, it is impossible to precisely finish the V groove with only the rough finishing grinder, and it is not possible to finish the shape of the V groove top with a particularly small radius of curvature, which is inconvenient for the function of the V ribbed belt. Is caused.

[Problems of conventional technology]

However, even if cutting is performed in two steps, heat is generated in each cutting process to some extent, which causes thermal expansion of the grinding machine and the material to be cut, which synergistically causes rib pitch deviation, rib crest deviation, and the like. Since it causes an error in finishing dimensions and wear of the grinding machine is also severe, it must be replaced relatively frequently.When this replacement is performed, it is necessary to make an adjustment in consideration of the shape error with the grinding machine used up to the previous time. There was a problem that management became very troublesome.

In particular, when a flexible elastomer is used in the belt compression section, the above-mentioned drawback becomes remarkable.

[Problems solved by the invention]

In view of the above-mentioned problems, the present invention eliminates the trouble of cutting in a two-step process, allows the V-ribbed belt to be manufactured in only one cutting process, and generates almost no heat during cutting and a molding error due to this. The present invention is made for the purpose of providing a method for manufacturing a V-ribbed belt.

[Technology for solving problems]

That is, according to the method for manufacturing a V-ribbed belt of the present invention, when a V-groove having multiple threads is cut and formed on the surface of a V-ribbed belt molding die formed of an elastomer material in a cylindrical shape, a milling blade is used as a V-groove bottom cutting blade. Further, the present invention is characterized in that, for V-groove side surface grinding, a multi-row V-groove is cut and formed at one time by a rotary grinding machine integrally having an abrasive grain grinding surface.

〔Example〕

 Next, the present invention will be described with reference to examples.

FIG. 1 is an explanatory view of the method of the present invention, and FIG. 2 is a side view of a rotary grinding machine used for carrying out the method of the present invention.

The method of manufacturing a V-ribbed belt according to the present invention is carried out by cutting and forming multiple V-grooves 2 ... on the outer circumference of a V-ribbed belt forming cylindrical mold 1 formed of an elastomer material as shown in FIG. As shown in FIG. 2, a rotary grinder 5 having a milling blade 3 as a blade for cutting out the shape of the bottom of the V-groove 2 and an abrasive grain grinding surface 4 for grinding the side surface of the V-groove is used for a multi-row V-groove at a time. It is configured to cut and form 2.

The method itself of applying the rotary grinder 5 to the outer periphery of the cylindrical mold 1 and cutting the V-grooves 2 ... Is the same as the conventional grinding method, and therefore detailed description thereof is omitted.

As the above-mentioned embodiment, the shape of the rotary grinding machine 5 is shown as one in which the milling blades 3 are integrally provided on the outer edge of the radial blade body provided with the abrasive grain grinding surface on the side surface of the V groove. Instead, as shown in FIG. 3, a rotary grinding machine 5 is formed by alternately arranging and forming blades 4 whose entire surface 5A is a grinding grain surface 4A and blades whose tip is a milling blade 3 alternately. May be used.

Which of the above rotary grinders 5 is to be used is appropriately selected depending on the hardness and softness of the material of the V-ribbed belt to be formed, the type of reinforcing fiber mixed therein, and the depth and width of the V-groove to be formed. To be done.

Further, the interval h between the radial outer peripheral edge 4'of the grinding grain surface 4 and the envelope outer peripheral edge 3'formed by the leading edge of the milling blade is approximately 0.
It is desirable to keep it to 3 mm or less.

The reason for this is that, as shown in FIG. 4, the shape of the grooves 2 ... 2 of the V-ribbed belt 6 is such that when engaging with the pulley 7, the V-groove 2 is made deeper with respect to the crest 7A of the pulley in order to improve transmission efficiency. The reason for this is that the gap H thus formed is used to exert wedge efficiency, and this gap is usually set to approximately 0.3 mm or less.

[Action]

When cutting and forming the V-grooves 2 ... Of the V-ribbed belt according to the present invention, if the rotating rotary grinding machine 5 is applied to the cylindrical mold 1, the grooves are first cut out by the milling blades 3 ... First, the side surface of the V groove is cut open by the grinding grain surface 4, and the cutting is completed by cutting the rotary grinding machine 5 to a predetermined depth.

At this time, the V-grooves 2, ..., 2 can be formed into a sharp shape because the tops of the bottoms thereof are cut by the milling blade 3. Moreover, since the V-grooves are formed by cutting, frictional heat is less generated. At the same time, even when forming the V-groove side surface by grinding, the portion that has been previously cut open with the milling blade 3 is in a state of being expanded by grinding, so the amount of friction is significantly smaller than when the V-groove is formed by grinding from the beginning. Also, the heat generated by grinding is reduced.

Therefore, the amount of heat generated as a whole during grinding is extremely small, and the occurrence of shape errors due to heat is reduced.

By the way, when the amount of heat generated when the V-grooves 2 ... 2 are cut out by the method of the present invention is compared with that of the conventional two-step grinding method, the results shown in FIG. 7 are obtained, and the method of the present invention is superior. found.

Further, according to the present invention, since the heat generation temperature at the time of forming the V groove is low, the forming accuracy of the V groove can be made excellent, and as shown in FIG. 6, the radius of curvature r of the groove top of the V groove 2 ... It was found that the belt transmission capacity as shown in FIG. 7 and the friction coefficient of the belt as shown in FIG.

In addition, the belt transmission capacity shown in Fig. 7 uses pulleys of 100 mm each as a driving pulley and a driven pulley.
The data is shown when a dead weight of 45 kgf is applied and the motor is rotated at 3500 rpm.

As for the friction coefficient of the belt shown in FIG. 8, as shown in FIG. 9, one end of the V-ribbed belt 6 molded by the method of the present invention is fixed via the load cell R and the other end is set to the drive pulley P having an outer diameter of 60 mm. Hang it and hang it vertically downward, and then 1.
The weight W of 75 kg was attached, the drive pulley P was rotated at 43 rpm, and the friction coefficient detected by the load cell at this time was measured.

〔effect〕

As described above, according to the present invention, when V-grooves are multi-row cut and formed, the groove bottom is temporarily finished by a milling blade and the groove side face is ground by a grinding surface. In addition, the number of molding steps is shortened to, and since the amount of heat generated is small, there is no molding error due to heat, and molding accuracy can be improved despite the small number of steps.
Therefore, it is possible to produce a high-quality V-ribbed belt having a low transmission capacity and a low friction coefficient.

[Brief description of drawings]

1 is an explanatory view of the method of the present invention, FIG. 2 is a side view of a rotary grinder used for carrying out the method of the present invention, FIG. 3 is a side view of another rotary grinder, and FIG. FIG. 5 is a sectional view showing the meshing state of the V-ribbed belt and the pulley, FIG. 5 is a graph showing the data of the grinding state by the method of the present invention, and FIG. 6 is an enlarged explanatory sectional view showing the meshing of the V-ribbed belt and the pulley. FIG. 8 is a graph showing the performance of the V-ribbed belt obtained by the method of the present invention, and FIG. 9 is an explanatory view of the test apparatus used to obtain the data of FIG.

Claims (4)

[Claims] 1. A milling blade as a V-groove bottom cutting blade, and a V-groove side surface grinding for cutting and forming multiple V-grooves on a surface of a V-ribbed belt molding die formed of an elastomer material in a cylindrical shape. As a method for producing a V-ribbed belt, a multi-line V-groove is cut and formed at one time with a rotary grinding machine integrally having an abrasive grain grinding surface. 2. A method for manufacturing a V-ribbed belt according to claim 1, wherein a rotary grinding machine having a radial blade body whose side surface is a grinding grain surface and whose tip is a milling blade is used. 3. A rotary grinding machine according to claim 1, wherein a rotary grinding machine is used in which blades whose entire side surfaces are grinding grain surfaces and blades whose tips are milling blades are alternately arranged in a radial pattern. V
Ribbed belt manufacturing method. 4. The distance between the envelope edge of the outer peripheral edge of the grinding grain surface in the radial direction and the envelope outer edge formed by the leading edge of the milling blade is 0.
The method for manufacturing a V-ribbed belt according to claim 1, 2, or 3, wherein the length is 3 mm or less.