Production process of polyurethane table tennis ball and table tennis ball

Abstract

The invention relates to a production process of a polyurethane table tennis ball. The production process comprises the following steps: weighing and mixing combined polyether and diisocyanate, injecting the mixture into a table tennis ball mold cavity, controlling the table tennis ball mold cavity to simultaneously rotate along an X axis and a Y axis which are perpendicular to each other, whereinthe X axis is parallel to a horizontal plane, and the Y axis is perpendicular to the horizontal plane; adjusting the rotating speeds in the two directions to 10 to 100 r / min, and controlling the rotating speeds in the X axis and the Y axis to be unequal, and placing the table tennis ball mold cavity in a constant-temperature environment at 45 to 70 DEG C for reaction for 3 to 10 min; and finallyopening the table tennis ball mold cavity for discharging, thus obtaining the table tennis ball. The table tennis ball obtained by the process disclosed by the invention is integrally molded at one time, so that no post-molding bonding or welding is needed; the wall thickness is uniform and controllable, and no connecting lines are formed; the table tennis ball produced by the process contains gaswith certain pressure; and furthermore, the pressure can meet a use requirement of the table tennis ball, and no extra inflation is needed.

Description

technical field [0001] The invention relates to a production process of a table tennis ball, in particular to a production process of a polyurethane table tennis ball. Background technique [0002] The structure of existing table tennis is usually: table tennis is connected into a hollow sealed ball by two hemispherical thin-walled plastic spherical shells by means of bonding, welding or pressing, and the outer surface of the ball reaches sealing after grinding. Requirements, that is, there are no obvious connecting seams on the outer surface of the ball, and the outer surface of the ball is a complete continuous spherical surface; the two hemispherical thin-walled plastic shells are generally extruded by a mold, and the burrs are removed at the edge of the car. The process is complicated, and the thickness of the table tennis ball is uneven, and the bounce is inconsistent. In addition, there are obvious seams on the surface of the table tennis ball. [0003] In terms of ma...

AI Technical Summary

Problems solved by technology

Some units or individuals have carried out research on this aspect. In terms of new table tennis molding technology, a kind of similar blow molding that plastics are first extruded and then entered into the mold twice is introduced in the patent application of Chinese Patent Application No. 01126885.9. However, the table tennis balls produced by this process have uneven wall thickness, so they cannot meet the T3 standard in terms of hardness and bounce.

In terms of new table tennis material development, the domestic application number is 90103206.9 in the patent application that introduced a kind of modified polystyrene as the main material; in the domestic application number is: 200680034220. Organic non-crosslinked polymer materials; domestic table tennis manufacturers such as Pisces and Double Happiness have also carried out related research on this aspect, but these new materials still use similar traditional table tennis techniques in the molding process of table tennis. Molding process, that is, to make a hemispherical shell by injection molding or stamping, and then connect the two hemispherical shells by bonding, welding, pressing, etc. The process is still as complicated as the traditional table tennis ball, even if the manufactured Table tennis meets the requirements of the T3 standard, and the production cost is difficult to reduce

[0005] There is also a method for preparing seamless table tennis balls in the current technology, but generally the materials are melted in a high temperature environment, and then rotated at high speed around two mutually perpendicular rotation axes, and the materials are evenly distributed in the spherical cavity by centrifugal force and gravity. In this method, the two rotation axes must pass through the center of the spherical mold cavity, and the two rotation axes are respectively recorded as the X axis and the Y axis, otherwise it is difficult to form a table tennis ball with uniform wall thickness. , so there can only be one spherical cavity on a mold, and it takes time to cool down after high temperature, and the processing efficiency is low

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