Plastic hook piece rolling mold

Abstract

The invention discloses a plastic hook piece rolling mold which comprises a hollow shaft, a plurality of working circular thin pieces, adjusting circular thin pieces and compression nuts, wherein the hollow shaft is composed of an upper shaft head, a lower shaft head, an outer conical cylinder between the upper shaft head and the lower shaft head and an inner conical expansion sleeve sheathed on the outer conical cylinder; the plurality of working circular thin pieces and the adjusting circular thin pieces are sequentially sheathed on the hollow shaft; the compression nuts are arranged at thetwo ends of the hollow shaft and compress the working circular thin pieces and the adjusting circular thin pieces; the compression nuts correspond to the diameters of the outer conical cylinder and the inner conical expansion sleeve; an annular shoulder is arranged at one end of the inner conical expansion sleeve; an axial opening is arranged on the peripheral wall of the inner conical expansion sleeve; and a cooling liner is arranged in the hollow shaft. The inner conical expansion sleeve with the axial opening expands under the extrusion of the compression nuts, thereby eliminating the radial clearances between the inner holes of the working circular thin pieces and the adjusting circular thin pieces and the central shaft, improving the coaxiality and roundness of the rolling mold and enabling the thickness of a plastic hook piece to be more uniform. In addition, through cooling of the cooling liner, the mold stripping effect of the rolling mold is improved.

Description

technical field [0001] The present invention relates to a plastic mould, in particular to a plastic hook piece rolling die, which includes a hollow shaft, a number of working circular slices and adjusting circular slices arranged on the hollow shaft; the working circular slices and adjusting circular slices They are sleeved on the hollow shaft in turn and compressed by compression nuts arranged at both ends of the hollow shaft. Background technique [0002] At present, the plastic hook piece rolling mold that adopts cylindrical structure has been reported, such as CN201175979Y discloses a special composite mold for the production of extrusion-type hook surface of hook and loop fasteners, including a central shaft, on which several It is a round sheet with the same outer diameter, and each round sheet is tightly pressed and fixed on the central axis to form an assembled and combined cylindrical structure. The outer edge of each round sheet is densely covered with multiple gap...

AI Technical Summary

Problems solved by technology

[0003] The above-mentioned two kinds of special-purpose mold combinations disclosed above have serious deficiencies in the combined structure and compacting method between related parts, which affect the quality of finished products; In the structure, multiple sheets are directly placed on the central axis. Professionals know that the cooperation between the inner hole of the sheet and the central axis is a relatively large clearance fit. It is difficult to control and guarantee the axiality and the roundness of the outer circumference of the cylinder, resulting in uneven thickness of the finished plastic hook (hook surface of the hook and loop fastener) and uneven height of the hook post; the working circular sheet and the adjusting circular sheet When assembled into a cylindrical structure, there is no accurate positioning device between the slices and the central axis, so that when the compression is fastened, due to the rotating force of the fastener or the end cap, there will be a gap between the outer edges of the adjacent working circular slices. The combination of transparent forming notches is not on the same generatrix of the cylinder, resulting in disordered distribution of the hook columns of the finished plastic hook piece, which cannot meet the use requirements

The central shaft described in the disclosure is a hollow shaft, and a heating rod or heating oil is poured into the cavity to form a heating device inside the mold. However, in the actual production process, the raw materials are melted at high temperature and become viscous. After passing through the smooth sheet mold, it becomes a continuous sheet and enters the plastic hook sheet rolling die. At this time, the continuous sheet is in a high temperature state, and its temperature is as high as about 200°C. The hook column must be cooled immediately instead of heated, otherwise the formed plastic hook piece cannot be peeled off from the rolling mold smoothly, and some hook columns adhere to the transparent forming gap of the working round sheet, which is easy to produce waste products

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