Clutch for multi-directional transportation device

A base for receiving a support surface comprising:

• (a) a longitudinally extending chassis having a front end, a rear end and a central portion positioned there between;
• (b) at least one drive wheel mounted on the central portion to engage the support surface on which the base is positioned, the at least one drive wheel is rotatably mounted to the central portion by a shaft;
• (c) a plurality of rotatably mounted wheels positioned around the chassis and mounted below the chassis to engage the surface on which the base is positioned;
• and,
• (d) a clutch including a lock operable to selectively lock the at least one drive wheel in at least a first preset position corresponding to a first direction of travel and a second preset position corresponding to a second direction of travel, the clutch includes a longitudinally extending first arm member having a longitudinal axis, the first arm member is configured such that a rotational force exerted on the shaft when the lock is in one of the preset positions is transmitted to the lock essentially along the longitudinal axis of the first arm member.

A method for altering the direction of a drive unit of a transportation device between a first direction of travel and a second direction of travel, the drive unit having a clutch, at least one drive wheel connected and a shaft extending vertically between the at least one drive wheel and the clutch, the shaft being rotatably mounted with respect to the transportation device between a plurality of positions each corresponding to the different direction of travel, the clutch operable to selectively lock the at least one drive wheel in a preset locked position corresponding to a direction of travel, the method comprising:

• (a) disengaging the clutch from a preset locked position in which an arm member connected to the clutch is positioned to be aligned with a force exerted on the arm member by the shaft due to an external rotational force applied to the shaft;
• (b) accelerating the shaft to rotate the shaft between a first position and a second position;
• (c) decelerating the shaft prior to the shaft moving to the second position such that the termination of rotation of the shaft at the second position does not jar the transportation device;
• and,
• (d) engaging the clutch in the respective preset locked position in which the arm member connected to the clutch is also positioned to be aligned with a force exerted on the arm member by the shaft due to an external rotational force applied to the shaft.

A base for receiving a support surface comprising:

• (a) a longitudinally extending chassis having a front end, a rear end and a central portion positioned there between;
• (b) at least one drive wheel to engage the surface on which the base is positioned, the at least one drive wheel is rotatably mounted to the central portion by a shaft, a second arm is non-rotatably mounted to the shaft;
• (c) a plurality of rotatably mounted wheels positioned around the chassis and mounted below the chassis to engage the surface on which the base is positioned;
• (d) a clutch having a cam member to selectively lock the at least one drive wheel in at least a first preset position corresponding to a first direction of travel and a second preset position corresponding to a second direction of travel, the clutch including a first arm non-rotatably mounted to the cam member;
• and,
• (e) a link member pivotally connected to both the first arm and the second arm and, when the cam member is in the first and the second preset locked positions, the first member and the link extend in a substantially straight line.

A base for receiving a support surface comprising:

• (a) a longitudinally extending chassis having a front end, a rear end and a central portion positioned there between;
• (b) at least one drive wheel to engage the surface on which the base is positioned, the at least one drive wheel is rotatably mounted to the central portion by a shaft, a second arm is non-rotatably mounted to the shaft;
• (c) a plurality of rotatably mounted wheels positioned around the chassis and mounted below the chassis to engage the surface on which the base is positioned;
• and,
• (d) a clutch to selectively lock the at least one drive wheel in at least a first preset position corresponding to a first direction of travel and a second preset position corresponding to a second direction of travel, the clutch including a first arm nonrotatably mounted to the cam member, the clutch comprising a cam member having a first engagement member corresponding to each of the preset locked positions and a second engagement member lockingly engagable with each of the first engagement members, the second engagement member moveable out of engagement with each first engagement member essentially without any frictional contact between the second engagement member and the cam member.