Abstract: A bus rooftop air conditioning system is made up of one or more self-contained modules having one or more evaporator sections and one or more condenser sections, with each extending transversely across the width of the bus, and with the evaporator sections fluidly communicating with both a common return air opening and a common supply air opening of the bus. The modules may be of a single unit configuration with a single condenser section and a single evaporator section or they may be of a double unit configuration having two condenser sections and two evaporator sections. The total capacity requirements are met by combining the use of single units and double unit configuration, with each of the evaporator sections communicating with a single return air opening and a single supply air opening in a bus.

Abstract: A module is provided for attachment to the roof of a bus and includes all of the necessary components for conditioning the return air from the passenger compartment and delivering conditioned air thereto. A plurality of modules can be mounted in various relationships to collectively provide the total capacity required by the bus. Each module includes an evaporator section, a condenser section and a power section including a compressor and an inverter. The evaporator sections have a return air compartment that extends a substantial distance across the roof of the bus such that a single design can meet the needs of various return air duct installations of various types of buses. Provision is made for the selective mixing of return air with fresh air, with the mixture then being passed by the evaporator blower through the evaporator coils and into the supply air ducts.

Abstract: Apparatus of removing condensate generated by a plurality of evaporator coils of a vehicular rooftop air conditioning unit. The unit further includes a condenser enclosure in which two opposed end walls are formed by a pair of condenser coils. A condenser fan is mounted for rotation in an opening in the top wall of the enclosure and is axially aligned along the central axis of the enclosure along with the fan motor which is suspended inside the enclosure beneath the fan. A slinger dish is mounted on the motor shaft beneath the motor in close proximity with the floor of the enclosure. The floor, in turn, slopes inwardly from all sides toward the center of the enclosure and condensate generated by the evaporator coils of the unit is channeled into the enclosure and collected in a recess beneath the motor.

Abstract: An air conditioning module having all the necessary components for conditioning air, is so sized and arranged that, when placed in an internal compartment of a bus, has its respective openings register with an existing return air duct and a supply air duct on the bus. The compartments and modules are so arranged that they can be paired in back-to-back relationship, with one on each said of a longitudinal center line of the bus. Each of the modules has an intermediate partition dividing the module into an upper evaporator section and a lower condensing section. A mixer flap is placed in an intermediate position with respect to the partition such that its position may be selectively adjusted to thereby vary the amount of fresh air and return air that is passed through the condenser coil and evaporator coil, respectively.

Abstract: A module is provided for attachment to the roof of a bus and includes all of necessary components for conditioning the return air from the passenger compartment and delivering conditioned air thereto. Each module includes an evaporator section, a condenser section and a power section including a compressor and an inverter. The evaporator sections have a return air compartment that extends a substantial distance across the roof of the bus such that a single design can meet the needs of various return air duct installations of various types of buses. Provision is made to interconnect a evaporator discharge opening with a supply air duct for the bus by way of a flexible duct having integrally formed end plates for connection by way of fasteners. The lower end plate which is secured to the supply air duct also includes an upstanding flange for connecting a protective cover thereto.

Abstract: In a bus rooftop air conditioner having a fresh air inlet for routing fresh air to an evaporator coil by way of a passageway and including a frame located in the passageway for the receiving a filter therein. A hinge mounted grill has a body portion for covering the fresh air inlet, while at the same time having a extended arm coming into contact with the filter to hold it in position. The filter can be removed and replaced by simply rotating the grill member to an open position to thereby disengage the extended arm from the filter and allow it to be removed. The grill member has integrally connected and substantially normally extending guide vanes near its other end which, when the grill is the covering position, extends into a condenser discharge opening to thereby act as diffusers within that opening.

Abstract: A compact rooftop air conditioning unit for a vehicle, such as a bus, having an evaporator coil located in front of a condenser coil. A plurality of cylindrical blowers are mounted adjacent the evaporator coil and arranged to provide conditioned supply air to the interior of the vehicle. A single electric motor is connected to an elongated drive shaft which drives the blowers. A condensate pump is included for pumping condensate generated by the evaporator coil back over the condenser coil. An electrically driven compressor is housed within the unit and is arranged so that no refrigerant lines pass outside of the unit. An inverter is also housed within the unit and provides a regulated input to the compressor and the blower drive motor.

Abstract: A compact rooftop air conditioning unit for a vehicle, said unit having an evaporator coil located in front of a condenser coil. At least one cylindrical blower is mounted adjacent the evaporator coil and is arranged to provide conditioned the blower and a condensate pump is secured to the shaft for pumping condensate generated by the evaporator coil back over the condenser coil. An electrically driven compressor is housed within the unit and is arranged so that no refrigerant lines pass outside of the unit. An inverter is also housed within the unit and provides a regulated input to the compressor and the blower drive motor. The heat exchanger coils are mounted in the form of two tube sheets take over the function of a housing, with the drip pan closing the bottom and the unit lid closing the top to form the completed unit.

Abstract: A low profile evaporator unit suitable for mounting on the ceiling of a small bus. The unit includes a cabinet containing an evaporator coil and a return air intake opening in the floor of the cabinet. A blower is mounted in the cabinet directly over the opening. A grill is non-removably mounted over the floor opening and a filter receiving tray is integrally joined to the grill so that the grill forms the bottom wall of the tray. Limited access is provided to the tray such that an air filter can pass into and out of the tray without removing the grill from the housing. Elongated narrow slits are also provided in the grill which further restrict access to the interior of the cabinet.

Abstract: A multi-stage absorption refrigeration system having an upper stage that includes a generator and condenser that operate at above atmospheric pressure and a lower stage that includes a generator and a condenser that operates at or near atmospheric pressure. The upper stage condenser is placed in heat transfer relation with the lower stage generator to produce refrigerant vapor from solution contained in the lower stage generator. A water condenser is connected to the lower stage generator so that vapor produced in the lower stage generator can be used to heat hot water or other fluid. When the system is placed in a water heating mode, the flow of solution is terminated to the upper stage generator and condensate leaving the upper stage condenser is circulated back through the upper stage generator.

Abstract: An evaporator unit for use in the passenger compartment of a small bus that includes a low profile cabinet mounted in the ceiling of the passenger compartment against the back wall of the compartment. The cabinet contains a housing having a floor that slants downwardly from front to back and an evaporator coil is mounted in the front of the housing that is tilted rearwardly to reduce the height of the cabinet. A tangential blower wheel is mounted behind the coil and arranged to pass air from an inlet in the floor of the housing through the coil and out of the cabinet outlet. A shroud surrounds the blower wheel that cooperates with a baffle plate to efficiently conduct air through the unit. The top edge of the baffle forms the lower lip of the shroud exit region and the plate extends downward so that its lower edge is adjacent to the bottom of the coil to establish a converging air passage with the rear face of the coil to evenly distributes the air flow passing through the coil.

Abstract: An absorption air conditioning machine that includes a main machine section containing an evaporator unit, an absorber unit, at least one generator unit, a condenser unit, and at least one solution heat exchanger. The heat exchanger tubes of the units and the solution heat exchanger are all supported within a pair of spaced apart tube sheets to provide a highly compact machine assembly.

Abstract: A refrigerant management system for use in an absorption cooling and heat machine that includes a holding tank for storing a given amount of refrigerant that is bled from the refrigerant supply line for bringing refrigerant from the evaporator sump into the evaporator header. A return line is located in the top of the tank which returns refrigerant from the tank to the sump when the tank is filled. A drain line containing a control valve is located in the bottom of the tank which, when opened, rapidly discharges the contents of the tank into the sump when the system demands additional refrigerant.

Abstract: A multiple effect absorption refrigeration system containing a plurality of paired generators and condensers that are staged to operate at successively higher temperatures and pressures. A solution to solution heat exchanger is associated with each stage to exchange heat between strong and weak solution circulating between the absorber and the generator of the various stages. A condensate to solution heat exchanger is included in at least one stage for placing condensate from the condenser of a higher temperature stage in heat transfer relation with solution being delivered into the generator of a lower temperature stage. Condensate from the condensate to solution heat exchanger is expanded to a system component that is operating at a pressure below the operating pressure of the stage being serviced by the condensate to solution heat exchanger.

Abstract: A heat pipe arrangement for exchanging heat between two different temperature fluids. The heat pipe arrangement is in a ounterflow relationship to increase the efficiency of the coupling of the heat from a heat source to a heat sink.

Abstract: A gas-to-liquid heat exchanger system which transfers heat from a gas, generally the combustion gas of a direct-fired generator of an absorption machine, to a liquid, generally an absorbent solution. The heat exchanger system is in a counterflow fluid arrangement which creates a more efficient heat transfer.

Abstract: A recuperator which recovers heat from a gas, generally the combustion gas of a direct-fired generator of an absorption machine. The recuperator includes a housing with liquid flowing therethrough, the liquid being in direct contact with the combustion gas for increasing the effectiveness of the heat transfer between the gas and the liquid.

Abstract: A coupled dual loop absorption system which utilizes two separate complete loops. Each individual loop operates at three temperatures and two pressures. This low temperature loop absorber and condenser are thermally coupled to the high temperature loop evaporator, and the high temperature loop condenser and absorber are thermally coupled to the low temperature generator.

Abstract: A heat exchanger bypass system for an absorption refrigeration system is disclosed. The bypass system operates to pass strong solution from the generator around the heat exchanger to the absorber of the absorption refrigeration system when strong solution builds up in the generator above a selected level indicative of solidification of strong solution in the heat exchanger or other such blockage. The bypass system includes a bypass line with a gooseneck located in the generator for controlling flow of strong solution into the bypass line and for preventing refrigerant vapor in the generator from entering the bypass line during normal operation of the refrigeration system. Also, the bypass line includes a trap section filled with liquid for providing a barrier to maintain the normal pressure difference between the generator and the absorber even when the gooseneck of the bypass line is exposed to refrigerant vapor in the generator.

Abstract: A triple loop heat exchanger for an absorption refrigeration system is disclosed. The triple loop heat exchanger comprises portions of a strong solution line for conducting relatively hot, strong solution from a generator to a solution heat exchanger of the absorption refrigeration system, conduit means for conducting relatively cool, weak solution from the solution heat exchanger to the generator, and a bypass system for conducting strong solution from the generator around the strong solution line and around the solution heat exchanger to an absorber of the refrigeration system when strong solution builds up in the generator to an undesirable level.