The Benefits of 420 Chrome Stainless Steel Coiled Spring Pins

In applications requiring a combination of high strength, superior fatigue life, and corrosion resistance, 420 martensitic chrome stainless steel offers a host of technical benefits and provides an overall robust cost-effective solution.

Automatic Transmission Shifter Housing

An automotive transmission shifter housing was initially designed to be attached to a floor mounted base by using a machined Solid Pin. The manufacturer recognized that the Solid Pin was expensive, and approached SPIROL for a recommendation to reduce the cost of the assembly. Both the shifter housing and the base to which it was attached were manufactured from plastic. Due to the fact that this was a mature design, the holes could not be changed as it would cost too much to modify the molds. Unfortunately this meant that a standard item could not be used, and therefore a special pin would have to be designed to accommodate the existing hole sizes.

The shifter housing was assembled by being lowered into the base and then subsequently pinned in place. The main purpose of the pin was to retain the housing to the base. Once assembled, there was limited loading applied on the pin.
app coiled pin automatic transmission shifter housing
app coiled pin automatic transmission shifter housing products

Former headed solid pin and SPIROL coiled spring pin

app coiled pin automatic transmission shifter housing close up
Based on the fact that the host material was plastic it was determined that a Light Duty Coiled Pin was the best option to satisfy the performance requirements, and concurrently meet the desired cost reduction. In addition, the symmetrical Coiled Pin was easier to feed and orient in automated equipment – a characteristic that contributes to improved efficiency and lower manufacturing costs. Because the Coiled Pin provided an interference fit in both components, potential vibration and/or noise was eliminated in the jointed assembly.

SPIROL Engineering designed a special diameter Light Duty Coiled Spring Pin that enabled the manufacturer to make a running change in the existing components. The Coiled Pin reduced the cost of the components and the cost of assembly through improved production efficiency. In addition to these benefits, the Coiled Pin enhanced the product quality by eliminating the potential for movement between housing and base.

Our staff of engineers will review your application needs and work with your design team to recommend the best solution.

Need help finding the right solution?

SPIROL offers complimentary Application Engineering support. We will assist on new designs as well as help resolve issues, and recommend cost savings on existing designs.