JPS5948748B2 - Driving belt made of rubber or rubber-like material having a rectangular shape, and its manufacturing method and manufacturing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a drive belt from rubber or rubber-like material with a square shape for synchronous motors with low torque, such as for example in the running gear of a cassette-tape recorder. First, a ring-shaped belt is molded and vulcanized, with one side having a smooth surface and the other side having a large number of ring-shaped protrusions that match the shape of the belt, and then this belt is vulcanized with the smooth surface facing outward. towards 2
The belt is tensioned over two turning rolls, which are provided with grooves corresponding to the protrusions into which the protrusions fit, and the belt rotating on the turning rolls is divided into individual rings from a smooth surface by an abrasive disc. be done.

A problem with conventional drive belts of this type is that their synchronization is insufficient.

Since the belt is manufactured transversely to the longitudinal axis of the tube by separation from the tube member, it has the disadvantage that it always has a tendency to twist when running over edges during operation and is therefore unstable.

Furthermore, when cutting narrow belts, it is virtually impossible to obtain a uniform width over the entire length of the belt.

Also, other known methods do not provide satisfactory synchronization.

In this method, the belt strips are separated from a tubular molded member whose inside is already individualized but still has the belt strips engaged over the skin layer by radial separation of the skin layer.

In this separation step, the tubular shaped part rotates over two turning rolls which are shaped according to the cross-section of the small belt by means of predetermined projections.

Since the finished small belt is rotated by the V-shaped groove in the roll, twisting thereof is unavoidable during operation.

This twist results in a large elongation at the outer edge of the small belt, so that it has a tendency to run up the guide surfaces of the grooves in the rolls during operation.

Due to this constant tendency of the small belt to ride up and come back again, synchronization is severely impaired.

The object of the invention is therefore to produce a square belt of the type mentioned at the outset with very good synchronization by a suitable method in a suitable device.

This object, according to the invention, in terms of method, is to produce the protrusion of the mold-vulcanized belt as a half-belt-shaped section bisected by two ridges, and to bring this belt into the operating state of the drive belt. The individual rings are separated from the belt in each half by means of an abrasive disc which is elongated by adjusting the axial distance of the corresponding deflection rolls and is provided with a groove corresponding in cross section to each half-belt shape, and the other half is cut off. This is achieved by forming a half-belt profile of the belt in question.

According to the method of the invention, the produced drive belt has two surfaces created on the belt by mold vulcanization and two surfaces processed by abrasive discs.

- Since the exact shape and arrangement of the abrasive disc on the force and of the deflection roll on the other hand can be realized technically, the cutting with the abrasive disc precisely completes the corresponding half-belt profile formed in the belt.

In the entire manufacturing process, it is important that the half-belt profiles each correspond to the diagonal cross-section of the drive belt, which has a square shape.

In this way, at the same time, the ring can be manufactured in a subsequent operating state, which has the advantage of rotating evenly and stably without a tendency to run-up.

An important feature of the method according to the invention is that the machining with the abrasive discs takes place on a belt that is elongated in accordance with the operating conditions.

This makes it possible to achieve a high degree of uniformity of the square cross section in the drive belt.

This and the suppression of the tendency to ride up make it possible to produce square drive belts with very good synchronization.

The turning roll can be made of steel, plastic or sufficiently hard rubber as desired.

Commercially available abrasive discs can be used, which can often be reshaped as they wear out.

Its precise shaping is critical to the results of the wheel force method.

The method of the invention is suitable for drive belts of various lengths and cross-sectional dimensions, with square side lengths of about 0.5 to 2.0 mm for the intended use of the drive belt mentioned at the outset.

It is clear that each ring size requires a suitable turning roll and a suitable abrasive disc.

Of course, on the vulcanization mold side, this compatibility with each rectangular shape of the drive belt is also important.

It is important in the apparatus for carrying out the method of the invention that the spacing between the grooves of the turning roll adapted to the elongation of the belt is smaller than the corresponding spacing in the vulcanizing mold, and that the corresponding spacing in the abrasive disc is smaller than the corresponding spacing in the turning roll. is to exactly match that of .

Here, when the belt stretches, its width becomes smaller,
The fact is taken into account that the individual half-belt profiles become closer together.

Other important features of the device are that the shape of the turning roll is formed by grooves accommodating half-belt shapes and shallower grooves, the grooves being arranged alternately; The groove has a V-shaped cross section with side surfaces perpendicular to adjacent groove sides.

This configuration allows a precise penetration of the abrasive disc into the belt, the sharp end of the abrasive disc protruding from the side edge of the half-belt profile so that it can be separated smoothly.

Hereinafter, the present invention will be described by way of example with reference to the accompanying drawings.

FIG. 1 shows a ring drive belt 2 rotating on a roll 1.
shows a cross-sectional view of.

Drive belts of this kind having a square shape are generally guided by ridges, and the rolls are provided with holes 3 in the area of the guide ridges 4 .

Within the scope of the method according to the invention, the belt 5 shown in enlarged cross-section in FIG. 3 is produced by mold vulcanization of rubber and has a surface with a smooth surface 6 and half-belt shapes 7 parallel to each other.

The belt 5 is removed from the vulcanization mold and tensioned with its smooth side 6 facing outwards against two turning rolls 8, 9 for the polishing process.

For this purpose, the belt 5 is pre-stretched strongly to correspond to the operating state of the subsequent drive belt.

According to the arrangement shown in FIG. 2, the left-hand deflection roll 8 is fixedly arranged, while the right-hand deflection roll 9 is moved by the left-hand deflection roll 8 by a sufficient length according to the arrow P1 until the desired belt extension is obtained. be moved away from.

In this case, the half-belt profile 7 on the inside of the belt 5 fits into the corresponding groove of the deflection roll.

FIG. 3 shows the form of the turning roll, taking the left turning roll 8 as an example.

The half-belt shape 7 of the belt 5 fits into a corresponding groove 10 of the deflection roll.

A small V-shaped groove 11 is provided between the grooves 10, into which a sharp rotating ridge 12 of an abrasive disk 13 is inserted.

Arrow P2 in the opposite direction to the rotation direction of the belt according to arrow P3
The abrasive disc 13 rotates according to the fixed turning roll 8
, according to the arrow P4, until the belt 5 is separated by the abrasive disk 13 into individual drive belts.

The individual drive belts are indicated in FIG. 3 by double lines within the cross-sectional view of the belt 5.

The finished drive belt 2 thus has two mutually adjacent abrasive surfaces and two surfaces produced by mold-vulcanization.

The guide ridge 4 and the counter ridge 14 have a small radius of rounding, which is due to the shape of the corresponding abrasive disc or vulcanization mold.

The spacing a between two adjacent grooves of the deflecting rolls 8, 9 is adapted to the elongation of the belt 5, and the unstretched belt 5 (removed from the vulcanization mold, not shown) fits into the groove. (as is) is smaller than the spacing between the half-belt shapes.

The gap between the two recesses of the abrasive disc 13 is likewise a, since the abrasive disc 13 is precisely adapted to the shape of the deflection rolls 8, 9.

[Brief explanation of the drawing]

FIG. 1 is an enlarged sectional view parallel to the running axis of the drive belt on a roll in operation, that is, being driven; FIG. The figure is an enlarged axial cross-sectional view of the abrasive disc, belt and adjacent turning roll, respectively. 1...Low #, 2...Drive heald, 3
...hole, 4 ... ridge, 5 ...
・Belt, 6...Smooth surface, 7...Half belt shaped part, 8, 9...Turning roll, 10...
...Groove, 11...Groove, 12...
... Rotating ridge, 13... Polishing disk, 14.
...Ridge.

Claims (1)

Claims: 1. A drive belt of rubber or rubber-like material with a square shape for synchronous motors with a small rotational moment, the drive belt having four sides, two of which are divided into individual belts. It is formed by polishing the outer surface of the molded ring folding belt 5, which has a half-belt-shaped part 7 on the inside, and the remaining two sides are formed with a mold, so that the four sides of the drive belt are precisely A drive belt characterized in that it is formed to ensure a high degree of synchronization. 2. When manufacturing a drive belt with a rectangular shape for a synchronous motor with a small rotational moment from rubber or a comb-shaped material, first a ring having one force side 6 having a smooth surface and the other side conforming to the belt shape is used. A ring-shaped belt 5 having a large number of projections is molded and cured, and then the belt 5 is
is stretched over two turning rolls with its smooth surface 6 facing outward, the turning rolls are provided with grooves 10 corresponding to the protrusions into which the protrusions are fitted, and rotated on the turning rolls 8 and 9. In a method consisting of cutting the belt 5 into individual rings from the smooth surface 6 by means of an abrasive disc 13, the protrusion of the mold-vulcanized belt is produced as a half-belt shape 7 bisected by two ridges. , the belt 5 is adjusted and stretched to a spacing between the axes of the deflection rolls 8, 9 that corresponds to the subsequent operating state of the drive belt, and the belt 5 is stretched by means of an abrasive disc, which in cross section is provided with a groove corresponding in each case to a half-belt shape. The individual rings are each divided into halves, the other half is formed by a half-belt-shaped section of the corresponding belt, and the shape of the turning rolls 8, 9 is divided into a groove 10 for accommodating the half-belt-shaped section 7 and a groove 10 for accommodating the half-belt section 7. These grooves 10 and 11 are arranged alternately, and each groove 11 has a V-shaped depressed cross section with a side surface perpendicular to the adjacent groove side surface. A method for manufacturing a drive belt characterized by: 3 Two deflection rolls 8, 9 are provided for tensioning thereon a mold-vulcanized connecting belt 5 having a smooth outer surface 6 and a protrusion on the inner surface corresponding to the belt shape, said deflection rolls corresponding to said protrusion. a groove 10 in which the protrusion fits, and one of the drive deflecting rolls 8 is further provided with an externally accessible abrasive disc 13 whose abrasive shape corresponds to the unformed vulcanized part of the belt shape. In the apparatus for producing a drive belt having a rectangular shape for a synchronous motor with a small rotational moment from rubber or rubber-like material, turning rolls 8, 9 adapted to the elongation of the belt 5 are provided.
the spacing between the grooves 10 on the vulcanization mold is smaller than the corresponding spacing on the abrasive disc 13, and the corresponding spacing on the abrasive disc 13 corresponds exactly to the spacing on the turning rolls 8, 9; The shape is formed by a groove part 10 for accommodating the half-belt-shaped part 7 and a groove part 11 having a shallower depth, and these groove parts 10 and groove parts 11 are arranged alternately,
The drive belt manufacturing apparatus is characterized in that the groove portion 11 has a V-shaped cross section with side surfaces perpendicular to the adjacent groove side surfaces.