JPH0230964B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a conveying means consisting of a pulley and a belt, and more specifically, a pulley having protrusions made of a conductive material protruding from the tops of its teeth. This method eliminates static electricity from the belt through the tensile member, and relates to an antistatic transport means used when transporting special capacitors, IC circuits, etc. that dislike static electricity.

[Prior art]

Generally, timing belts are made of synthetic rubber such as chloroprene rubber or nitrile rubber, or polymeric materials such as polyurethane rubber, and are reinforced by embedding steel cords, fiber cords (glass fibers, aramid fibers), etc. in the length direction. ing. When these polymeric materials are in use, static electricity is generated due to friction, which causes dust adhesion and dielectric breakdown, resulting in defective products being transported.

Timing belts are widely used as conveyor belts because they allow more accurate conveyance than V-belts, are lighter than chain belts, and can operate at higher speeds. However, timing belts are more difficult to prevent from charging than other belts. That is, in the case of a chain belt, since the chain itself is a conductor, it is sufficient to simply ground it. Flat belts and V-belts can prevent static electricity by making the contact surface with the pulley a fabric surface with metal thread woven into it and grounding the pulley.

As the antistatic means for the timing belt, an antistatic material containing an antistatic material is used.
Taking polyurethane as an example, it usually shows a static value of 250-400V, but if antistatic material is used, it will be 30V.
decreases to 30V is not a problem for general use, but it can be a problem when transporting items that are particularly sensitive to static electricity, such as special capacitors and IC circuits.

[Problem that the invention seeks to solve]

SUMMARY OF THE INVENTION An object of the present invention is to provide a conveying means consisting of a pulley and a belt that reduces the static electricity value to substantially zero when the type of conveyed object is likely to be adversely affected by a small amount of static electricity.

[Means of problem solving]

The present invention meshes with a pulley having protrusions made of a conductive material protruding from the tops of its teeth,
It consists of a toothed belt in which a conductive tensile body is buried and the tensile body is exposed at the core wire holding part, and when the pulley and the toothed belt mesh, the protrusion and the tensile body are It is characterized by direct contact and the pulley being grounded.

The protrusions of the present invention are made by forming a conductive material such as copper or brass into a thin chevron-shaped filament, and embedding the protruding tip at the top of the teeth of the belt by punching or the like. The cross-sectional shape of the protrusion is not particularly limited as long as it can come into contact with the tensile member of the belt, but if the tip has a semicircular shape that matches the width of the core wire holding part, contact will be ensured.

The belt must be made of a conductive tensile material such as a steel cord, must have a core holding part, and must have the tensile material exposed at this portion. The exposed portion of the tensile material comes into contact with the protrusion of the pulley, allowing static electricity to be discharged from the grounded pulley. If the pulley is made of carbon steel for mechanical structures, rolled steel for general structures, etc., it may be grounded. If the pulley is made of non-conductive material such as nylon, the end of the protrusion may be guided by a conductive wire and grounded on the end face of the pulley.

It is not necessary to provide ridges on all the teeth, but it is necessary that at least one tooth with ridges be in contact with the tension member of the belt when the pulley engages with the belt. Therefore, if the number of teeth of the driving pulley and the driven pulley are the same, it is sufficient to have at least three protrusions equally spaced (120°).

Hereinafter, the present invention will be described in detail by way of examples with reference to the drawings.

〔Example〕

FIG. 1 is a perspective view showing a state in which the pulley and belt are engaged, and FIG. 2 is a sectional view showing a state in which the pulley and belt are engaged. 1 is a pulley, and 2 is a belt that meshes with the pulley 1. 3 is a tooth of a pulley, 4 is a tooth of a belt, and 5 is a tensile member made of a steel cord. The tensile member 5 is exposed at the core wire holding portion between the teeth. Numeral 6 is a protrusion, which is embedded in the top of the teeth 3 of the pulley by being clicked. In this example, it was made of copper and had a mountain-shaped cross-sectional shape with a base of 1 mm, a height of 0.4 mm, and a radius of curvature of 0.2 mm at the top, with the top protruding. Reference numeral 7 denotes a conducting wire for guiding static electricity from the protrusion 6 to a ground wire (not shown). In this embodiment, since nylon was used as the material for the pulley 1, a conductor was required, but this is not necessary if the pulley material is a conductor such as steel.

When the pulley and belt are engaged, the second
As shown in the figure, the protrusion 6 provided on the top of the teeth 3 of the pulley is in direct contact with the tensile member 5, and the static electricity of the belt material can be removed via the protrusion 6.
When ordinary polyurethane rubber was used as the belt material, the electrostatic value was approximately 0 to 20V, and when polyurethane rubber added with an antistatic material was used, it was approximately 0V.

〔effect〕

According to the present invention, in a timing belt used for conveyed objects that are easily affected by a small amount of static electricity, the static electricity value can be reduced to substantially zero by using it in combination with an antistatic material.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and FIG. 1 is a perspective view of a state in which a pulley and a belt are engaged, and FIG. 2 is a sectional view showing a state in which a tensile member and a protrusion are in contact. In the drawings, 1 is a pulley, 2 is a belt, 3
4 is a tooth of a pulley, 4 is a tooth of a belt, 5 is a tensile member, 6 is a protrusion, and 7 is a conductor.

Claims (1)

[Scope of Claims] 1. A pulley having protrusions made of a conductive material projected from the tops of its teeth, a conductive tensile body embedded in the pulley that meshes with the pulley, and a conductive tensile body embedded in the core wire holding part. The antistatic device comprises an exposed toothed belt, and when the pulley and the toothed belt engage, the protrusion and the tensile member directly contact each other, and the pulley is grounded. Means of transportation. 2. The antistatic conveying means according to claim 1, wherein the tensile member is a steel cord.