DE3400219A1 - Method of manufacturing securing rings - Google Patents

Abstract

The invention relates to a method of manufacturing slotted securing rings, the ring cross-section of which changes in the circumferential direction. During winding of a cross-sectionally rectangular or trapezoidal steel wire in helical form, an already hardened or patent-hardened material is used, as a result of which a final hardening of the finished securing rings can be omitted. This method sequence leads to less expensive production, the finished securing rings having lower manufacturing tolerances and a greater toughness.

Description

Process for the manufacture of locking rings

The invention relates to a method for producing circlips according to the preamble of the main claim.

Retaining rings, for example according to DIN 471, 472 have a radial Resilience and are therefore usually made of spring steel. Included the final shape is punched out of flat sheet metal and then hardened. This method has the disadvantage that a considerable amount of waste material is generated, that are only rarely reused for the production of other rings can.

Therefore, more economical processes have been developed in which a steel wire with a rectangular cross-section is wound in a spiral shape and then is axially slotted.

The resulting slotted rings are given their final shape by punching Shape and are then hardened. Information on this process technology can be found in the Read the magazine "verbindungsstechnik ", 8th year (1976), issue 6/7.

The winding creates a steel wire with a rectangular cross-section trapezoidal, so that it is expedient to use one already with a trapezoidal cross-section used steel wire to compensate by reverse winding to achieve the cross-sectional deformation.

This process technology is already described in DE-OS 2 021635, metal ring of a general type being produced without subsequent machining steps will. As a result of the necessary stamping processing, it has been customary to date from soft wire materials and the circlips finished in their shape to harden finally. Retaining rings produced in this way have the disadvantage that strong dimensional and shape deviations are accepted as a result of the hardening process that can no longer be eliminated in the series. Continue to get caught the rings into each other during hardening, so that a subsequent complex Isolation becomes necessary. In addition to the hardening processes known in all of these Occurring high costs must still have an often insufficient toughness of the Materials are accepted.

The object of the invention is to provide a method for producing slotted To create circlips, whereby smaller manufacturing tolerances with little effort in terms of shape and dimensions and higher material toughness is achieved.

The object is achieved in that a hardened material is used as the starting material Steel wire is used. This allows a final hardening of the finished locking rings omitted.

The steel wire can be made with the required cross section as already Hardened raw product can be obtained inexpensively The hardening is in this condition much easier, which means the proportional surcharge compared to a soft steel wire compared to the effort involved in subsequent hardening of individual circlips is only a fraction. It is therefore no longer necessary to harden the rings so that the hardening systems at the manufacturer of the locking rings are advantageously omitted and problems caused by the rings getting stuck no longer arise. Wrapping one Experience has shown that steel wire with the required hardness makes a pro flower. It you just have to make sure that the increased internal stress with a larger one Expansion of the helix must be expected. However, this can be calculated precisely beforehand or determine it experimentally. Only when punching the rings into their final Form, a somewhat more resilient tool must be used1 to achieve the higher To be able to absorb loads when processing the hardened material. Huh The circlips have their final form1 with regard to these steps the dimensions only depends on the punching tool and is therefore extremely precise and in the series is advantageously afflicted with the lowest manufacturing tolerances. Farther are also twisting1 one-sided warping or deviations from the circular shape locked out.

According to a further feature of the method according to the invention a steel wire hardened according to DIN 17 014 patent is used. This will be the greatest possible Toughness of the material of the circlips achieved e so that the risk of breakage as a result Very little embrittlement is. Furthermore, this steel wire the surface is much less susceptible than normal hardened materials against hydrogen brittleness achieved, which is particularly important when applying a Surface protection by electroplating is.

The method according to the invention can be used for the production of all circlip sizes be used.

Claims (2)

Method of manufacturing circlips P a t e n t a n 5 r ü ch e 1. Process for the production of slotted circlips with in Circumferential direction changing cross-section in the following steps a) Winding a Steel wire with a rectangular or trapezoidal cross-section in a spiral shape with turns lying axially against one another b) slots of the helix in the axial direction c) Flat pressing of the individual rings d) Punching the rings into their final shape characterized in that a hardened steel wire is used as the starting material will. 2. The method according to claim 1, characterized in that a according to DIN 17014 patent-hardened steel wire is used.