When the main pump located in the upper car body delivers oil to the travel motor located in the lower car body, it will make relative rotation due to getting on and off the car. In order to prevent the hydraulic hose from twisting, a central swivel joint is installed in the center of the vehicle body.
working principle:
The center swivel joint is composed of a shell and a mandrel. The shell is installed on the lower vehicle body, and the mandrel is installed on the On the upper vehicle body.
An annular groove with the same number of pipes is opened on the mandrel, and the hydraulic oil from the mandrel inlet flows from the housing through these grooves The vertical holes in the supply the propel motor.
Even if the mandrel rotates continuously with the upper vehicle body, the groove on the shell is kept unblocked with the oil port on the mandrel, so that the hydraulic oil can enter and leave freely.
