Spring plungers; simple components with endless applications

From locking, to locating and indexing, positioning and clamping, to securing, ejecting, notching and dampening, a spring plunger is a vital component in the design engineer’s toolbox.  

Spring plungers are simple devices and consist of only three components: a body, spring, and ball. The body is typically manufactured from steel or stainless steel, and threaded, enabling quick and secure installation in any orientation.  

Spring plungers allow for accurate, repeatable, and rapid adjustments on a variety of platforms, fixtures, and furniture. The basic function of a spring plunger is achieved by the internal spring that maintains a constant force on a steel or stainless-steel ball, thereby always ensuring the ball remains in an extended or retracted position.  

In most cases a notch or series of notches is present in the counterpart. In this case the ball will remain in the retracted position until it meets a notch in the counterpart, then the spring force will push the ball into the notch and create a temporary ‘lock’ until sufficient lateral force is applied to compress the spring, retract the ball, and allow the object to move again. This ball and spring combination ensures wear on the counterpart is minimised, and maintenance is virtually zero.  

Rencol’s spring plungers are available in steel and stainless steel, in metric sizes from M3 up M20. Our clients include manufacturers of gym equipment, medical aids, catering equipment, conveyors, aerospace, defence, automotive. We have large stocks in Bristol, all ready for shipping to you in just 48 hours.