Press and tooling combination doubles output of bush and ball joint insertion for control arm assembly by allowing two bushes to be inserted and tested in a single press cycle.

PJ Hare has developed a press and tooling combination that dramatically speeds up bush and ball joint insertion for control arm assembly in automotive applications. The new application, designed to benefit long- and medium-run production runs, doubles output by allowing two bushes to be inserted and tested in a single press cycle. As well as speeding up production, the whole process is designed to aid subsequent production line assembly of control arms by improving the accuracy and consistency of assembled components.

This has been achieved by fitting the bushes relative to each other rather than just inserting them into the control arm alone.

John Thatcher, managing director of Hare, added: 'Whilst offering immediate production benefits, the use of hydraulic presses and dedicated tooling, rather than a special purpose machine, means that the equipment is not redundant after production of the particular vehicle ceases.

The presses can be used for future vehicles with only new tooling required to accommodate changes in component size.' The machinery comprises four hydraulic presses, delivering pressure from above and below.

Each is equipped with bespoke tooling and dedicated to the front upper, front lower, rear upper and rear lower pairs of control arms.

Bushes are inserted in a vertical orientation with one bush inserted from below at one end of the control arm and the other inserted from above at the opposing end.

The interference fit of each assembly is load tested using a sensor.

Between the insertion of the first and second bushes, a Linear Variable Displacement Transducer (LVDT) measures the vertical distance between the bushes and relays information back to the PLC control unit to guide the press to the correct position for securing the second bush.

Use of the LVDTs facilitates a consistent and predictable displacement along the component length from bush to bush, and thus aids the process of attaching the control arm to the chassis further down the production line.

As well as bush assembly, further presses can be added to the suite for the insertion of ball-joints and circlips to complete the assembly of the front upper and lower control arms.

Once again, whilst the tooling is vehicle specific, the press can be re-used for future vehicles.

Thatcher added: 'This application has been developed to improve quality and quantitative improvements for long vehicle production runs.

We expect to announce an economical solution for short-run and specialist vehicles in the near future.'