Automatic sliding panel operators

Claim 1

IN AN AUTOMATIC SLIDING PANEL OPERATOR, A DOUBLE ACTING PISTON, A PANEL CONNECTING MEANS ACUTATED BY SAID PISTON, A SOURCE OF SUPPLY OF PNEUMATIC PRESSURE, CONDUITS LEADING FROM SAID SOURCE OF SUPPLY TO SAID PISTONS, VALVES IN SAID CONDUITS SELECTIVELY CONTROLING THE FLOW OF PRESSURE TO ONE SIDE OF SAID PISTON TO MOVE SAID PANEL IN ONE DIRECTION AND TO THE OTHER SIDE OF SAID PISTON TO MOVE SAID PANEL IN THE OPPOSING DIRECTION AND TO PROVIDE A SUPPLY OF CUSHIONING PRESSURE AGAINST SAID PISTON UPON NEARING COMPLETION OF ITS MOVEMENT IN ONE DIRECTION, SOLENOIDS CONTROLLING SAID VALVES, AN ELECTRICAL CIRCUIT IN CONNECTION WITH SAID SOLENOIDS, A SWITCH IN SAID CIRCUIT FOR ENERGIZING ONE OF SAID SOLENOIDS TO OPEN ONE OF SAID VALVES TO MOVE SAID PISTON IN ONE DIRECTION, A TIME DELAY SWITCH IN SAID CIRCUIT SIMULTANEOUSLY ACTIVATED WHICH HOLDS SAID SOLENOID OPEN A PREDETERMINED LENGTH OF TIME, LIMIT SWITCHES IN SAID CIRCUIT ACTIVATED BY CONTACT WITH THE PANEL CONNECTING MEANS TO ACTIVATE ONE OF SAID SOLENOIDS AND ONE OF SAID VALVES TO DISCHARGE A SUPPLY OF PRESSURE AGAINST THE SAID PISTON OPPOSITE ITS DIRECTION OF MOVEMENT TO CUSHION THE STOP OF THE PISTON.