Abstract: A heat pump water heater has a tank, a heat source, and a heat pump system. The heat pump system has a refrigerant path, at least a portion of which is in thermal communication with the water tank volume so that heat transfers from refrigerant to the water tank volume. A fan causes air to flow through a housing, and another portion of the refrigerant path includes an evaporator in the housing. The fan is within the housing and may further be within a second housing. The first housing may comprise a baffle to direct air flow. The fan may be a variable speed fan in communication with a controller, so that the controller controls the fan speed depending on a temperature of the refrigerant.

Abstract: A tunnel boring machine (90) having a rotating cutter head (93) that rotatably supports a plurality of cutter assemblies (10). A plurality of instrument packages (50) are attached to the rotating cutter head, each instrument package having a distal end in contact with an associated cutter assembly. The instrument packages include a plurality of sensors including an accelerometer (32), magnetometer (33) and temperature sensor (34), for monitoring the associated cutter assembly. The sensors are mounted in a distal end of the instrument packages that is biased to remain in contact with the cutter assembly. The instrument packages include a wireless transmitter, and they are interconnected in a mesh or peer to peer network. A power supply (176) such as a battery pack is provided for each instrument package. The data from the sensors may be used to control operation of the tunnel boring machine and/or to monitor the condition of the cutter assemblies.

Abstract: A tunnel boring machine (90) having a rotating cutter head (93) that rotatably supports a plurality of cutter assemblies (10). A plurality of instrument packages (50) are attached to the rotating cutter head, each instrument package having a distal end in contact with an associated cutter assembly. The instrument packages include a plurality of sensors including an accelerometer (32), magnetometer (33) and temperature sensor (34), for monitoring the associated cutter assembly. The sensors are mounted in a distal end of the instrument packages that is biased to remain in contact with the cutter assembly. The instrument packages include a wireless transmitter, and they are interconnected in a mesh or peer to peer network. A power supply (176) such as a battery pack is provided for each instrument package. The data from the sensors may be used to control operation of the tunnel boring machine and/or to monitor the condition of the cutter assemblies.