摘要 |
<p>An apparatus (10) for pressurizing a pneumatic tire (5) mounted on a vehicle (3, 11) wheel which includes a displacement type air pump (12) having a spring loaded piston (16) and cylinder (17) combination for generating air under pressure. The air pump (12) is axially (27) attached to the vehicle wheel (3, 11) and an air pressure connection conduit (7, 15) introduces air under pressure generated from the pump into the pneumatic tire (5). A cam (23) and cam follower (28) arrangement is mounted in the housing (13) for the pump (12) for creating relative cam actuated movement therebetween which is utilized for driving the air pump (12). A pendulum (24) is mounted for free axial rotation relative to the pump housing (13) and the pendulum (24) is connected to one of the cam (23) or cam follower (28), and the other is secured to the pump housing (13) for rotation therewith to provide this cam actuated driving movement. The axis (27) of piston reciprocation in its cylinder (17) is substantially aligned axially with the wheel (3, 11) axis of rotation (27). In addition, the cam follower (28) is provided with a ramp tracking surface (31) having points of maximum (31) and minimum (31) rise which dictate the limits of reciprocation of the piston and a step (29) in this cam follower surface (31) is provided which connects the maximum and minimum points of rise (31) for providing a rapid compression stroke of the piston (16) under spring bias.</p> |