I am looking for push button variable resistors. These are used in a Caterpillar forklift to control the fork tilt up and tilt down. Caterpillar no longer supports this machine.
One feature that makes these unique is the two wipers on each resistor that resemble a record player needle.
These resistors measure 1k ohms at the beginning (top) of their stroke and end the stroke around 300 ohms. They are taking a 4.5 volt DC input and gradually reducing it down to ~1.5VDC
I can redesign the control joystick to accommodate what you have available. The current resistors travel about 12mm.
A brand name of “Lumatic” is shown on one existing resistor.
Thank you,
Jim
Welcome to the forum.
Based on your description and photos, they appear to be slide, (AKA linear motion) rheostats (2 lead potentiometers) with a mechanical stop 300 ohms before the low end termination.
Back in the 70s/80s there where a number of potentiometer companies that offered linear motion pots with a parallel shaft. This century all I’ve seen are slide pots with perpendicular shafts (e.g. on audio mixers). Another problem is that the available slide pots are not mechanically rugged or sealed against dust so even if you can make it work, it likely will not last long in that application.
Here’s the Digi-Key table of currently available slide pots:
https://www.digikey.com/short/p4wd8z3w
Thank you Paul,
This information is useful because now I will plan to replace the tilt control. Maybe a mechanical hydraulic lever is the best choice. Meanwhile I have been successful slightly bending the wipers for better contact and I have been applying some Stabilant 22 periodically. These pots send the signal to a control board and that board is obsolete as well.
Thanks again,
Jim