Abstract: An automated order fulfillment system and mobile robot are disclosed, where the mobile robot includes a compliant drive for moving between levels of a multilevel storage structure. In one example, the compliant drive comprises a drive shaft having splines configured to provide rotational play that prevents jamming of a vertical drive gear on the end of the shaft with a rack in a vertical track.

Abstract: A load control system and method of time multiplexing power to a plurality of holding shelves in a food holding cabinet to allow total cabinet power to be limited to electrical distribution capabilities. This method allows for individual shelf heaters to be utilized normally to maintain food temperatures during normal use and modulates power when multiple shelves demand heating that would normally exceed branch circuit capabilities thus tripping the breaker. The system monitors temperature of each shelf and based upon demand executes a logical demand schedule for each shelf heater output (time multiplexing or modulating AC power to each) such that total system demand does not exceed available power to the system.

Abstract: A load control system and method of time multiplexing power to a plurality of holding shelves in a food holding cabinet to allow total cabinet power to be limited to electrical distribution capabilities. This method allows for individual shelf heaters to be utilized normally to maintain food temperatures during normal use and modulates power when multiple shelves demand heating that would normally exceed branch circuit capabilities thus tripping the breaker. The system monitors temperature of each shelf and based upon demand executes a logical demand schedule for each shelf heater output (time multiplexing or modulating AC power to each) such that total system demand does not exceed available power to the system.

Abstract: A temperature sensing assembly for a heat exchanger flow tube comprises a housing having a thin heat transmitting wall section in heat conducting engagement with a flow tube, and a relatively thick, heat insulating structural support wall section; a thermally responsive signal producing assembly comprising an electrical signal producing element in heat transfer relationship with the heat transmitting wall section; a heat transfer element between the housing and heat exchanger flow tube tending to maintain the flow tube and heat insulating wall section temperatures the same; and an insulating jacket surrounding part of the heat transfer element.

Abstract: A self-calibrating defrost controller for use with heat pump. The outdoor heat exchanger coil of a heat pump is defrosted based upon either compressor run-time exceeding 6 hours, or the temperature difference between the coil and ambient air exceeding a value that changes depending upon outdoor coil temperature. A programmable controller mounted to a printed circuit board within a housing executes a control program to monitor temperature sensor produced temperature signals. One sensor that monitors ambient temperature is mounted to the printed circuit board that also supports the programmable controller.

Abstract: A temperature sensing assembly for a heat exchanger flow tube comprises a housing having a thin heat transmitting wall section in heat conducting engagement with a flow tube, and a relatively thick, heat insulating structural support wall section; a thermally responsive signal producing assembly comprising an electrical signal producing element in heat transfer relationship with the heat transmitting wall section; an anchoring arrangement for positioning the signal producing element in heat exchange relationship with the heat transmitting wall section; a heat transfer element between the housing and heat exchanger flow tube tending to maintain the flow tube and heat insulating wall section temperatures the same; and an insulating jacket surrounding part of the heat transfer element.

Abstract: A defrost controller for a refrigeration system. The system includes a circuit having a programmable controller which monitors compressor demand from a thermostat and uses alternating current cycles of a line voltage to control on and off cycles for a defrost mode of the refrigeration system. An anti-short cycle feature is optionally included to inhibit compressor operation for a predetermined interval each time the compressor is disabled.