To provide a variable transmission device which prevents reverse out-flow of a given command by reaction force of a transmission body, in order to the following problems: huge elastic force and pressurizing force cross each other to flow out to the outside of the pressurizing device during transmission to cause a malfunction, while high operability and controllability are required when a transmission repeats increasing/reducing pressure or increasing/decreasing speed or the like in response to a command.

A command transmitter is formed of a worm transmitter for transmitting a reverse command for applying high operability to a sliding device of a pressurizing device through a ball medium in only one way from a driving source to a sliding device.In the variable transmission device, the command transmitter is coupled to a sliding device so as to prevent the reverse out-flow of a given command to the outside of the pressurizing device.