Braking control apparatus for an electric motor operated vehicle

Claim 1

A braking control apparatus for an electric motor operated vehicle including a DC motor for operating the vehicle, contactor means for effecting change-over between forward and backward modes of operation of the vehicle and a chopper circuit having a duty cycle varying in response to an accelerator so as to control the speed of the vehicle, said apparatus comprising forward/backward change-over detecting means for detecting a change-over from said forward mode of operation to said backward mode of operation or vice versa, and regenerative braking activating means for effecting regenerative braking when said forward/backward change-over detecting means detects said change-over from said forward to said backward mode of operation or vice versa, said forward/backward change-over detecting means and said regenerative braking activating means including: first means for detecting the duty cycle of said chopper circuit; second means for detecting whether a level detected by said first means is higher or lower than a predetermined level; third means for detecting whether an output of said accelerator is greater than a predetermined value; fourth means for detecting the operation of forward/backward switch means so as to generate a clock signal; and fifth means for detecting that there is no output from said second means and that the value detected by said third means is greater than said predetermined value and responsive to said clock signal from said fourth means to energize contactor excitation coil means.