Control knobs and valves fitted to therapeutic medical mattress are produced by Replas.
There are 19 control knobs and valves located down the side of the mattress which can be rotated to allow inflation of deflation of individual cells.
To provide relief where a patient has a vulnerable area, such as a wound or ulcer, to off load the pressure point the adjacent cell can be easily deflated
Several years previous Replas was asked to build soft a series of development tools whilst the product was developed and tested for a low volume product. So successful and functional the product was to be introduced on the customer’s flagship model. The product would require some alterations to improve its look, ergonomics and reduce cost to suit a higher volume product.
The client’s specification required a positive grip on the Control Knob for quick rotation and ease of use by medical staff. Volumes were to be modest so tooling costs had to be minimized whilst achieving a quality and ergonomic part to suit the application.
To stay within a modest tooling budget Replas proposed a semi-automatic process to produce a two part “overlay” moulding.
The reduce piece price cost the ‘hard’ shell moulding would be moulded on a fully automatic 2 impression tool, moulded in white Exxon Polypropylene.
To reduce customer’s final assembly time and cost the knob also had a build in clip and orientation feature for quick engagement to the Control Valve.
The Knob is then inserted into the second stage tooling and a tactile Thermoplastic Elastomer (TPE) overlay plastic (a grade of PTS Thermoflex was chosen for its excellent adhesion to polyproylene), moulded in the company’s corporate blue colour is injected over and around the hard shell. The result gives the desired “feel and grip”, and also provided an arrow indicator and thus removing the need for an additional printing process again keeping cost down.
