Abstract: A refrigeration and defrost system utilizing various valves for opening a defrost line to hot gas and regulating the pressure in refrigerant lines. A slug surge suppressor is provided at several points in the defrost and refrigerant lines to alleviate hydraulic shock damage caused by liquid/gas "slugs" passing rapidly through the lines. The slugs are commonly formed by the required rapid opening of the various valve of the system. Capillary passages in the suppressor resist liquid flow while allowing gas to flow freely.

Abstract: An improved gas pumping recirculating refrigeration system is disclosed. A controlled pressure flash tank provides flash gas for forcing liquid refrigerant from a dump tank. A controlled pressure receiver receives liquid from the dump tank and recirculates it to an evaporator. The flash gas pressure in the flash tank is controlled by a pressure regulator valve connected between the controlled pressure flash tank and the controlled pressure receiver. The pressure regulator valve may set so that the flash gas in the flash tank is at the pressure needed to force liquid from the dump tank. Thereby, optimum refrigeration efficiency is achieved with very little energy waste.

Abstract: A refrigeration system utilizing hot gas for defrost and a hot gas defrost valve with specific opening characteristics for rapidly reducing the pressure gradient across the valve without producing hydraulic shock. When defrost is called for by the system, the hot gas defrost valve is opened in a manner which prevents a liquid or liquid-gas slug from impacting on cold system components and producing liquid hammer effect damage.

Abstract: A refrigeration and defrost system utilizing various valves for opening a defrost line to hot gas and regulating the pressure in refrigerant lines. A slug surge suppressor is provided at several points in the defrost and refrigerant lines to eliminate hydraulic shock damage caused by slugs of a liquid-gas mixture passing rapidly through the lines. The slugs are generally formed by the required rapid opening of a hot gas defrost valve and a pressure regulatory valve of the system. A series of capillary passages in the suppressor are operative to resist the flow of liquid while allowing gas to flow freely. Tangential velocity is imparted to the slug to separate the liquid and gas components of the slug.

Abstract: A wheel construction and arrangement wherein a wheel which has a relatively wide surface contact tire, pneumatic, for example, is mounted for rotation in a yoke which extends in the direction of travel of the vehicle which the wheel supports. The yoke is tiltable on a substantially horizontal axis which extends below the wheel axis and relatively close to the supporting surface. Lateral displacement of the body to which the yoke (and wheel) is attached will cause the wheel to tilt in that direction and any subsequent longitudinal motion in either direction of wheel travel will result in the wheel righting itself; i.e., correcting for that displacement. Conversely, tilting of the yoke and wheel to a certain degree will cause the wheel to travel in a precisely prescribed arc. The vertical plane in which the tilt axis lies passes through the area of tire contact with the supporting surface regardless of the angle of tilt.

Abstract: An improvement in a recirculating refrigeration system which includes an "economizer" compressor. The economizer compressor is in a flash gas handling sub-system which receives flash gas from the primary system at a substantially higher input pressure than the primary compressor. As a result the load on the primary system compressor is reduced. The overall effect is a more efficient system, using less power.

Abstract: A drive mechanism for converting rotary to linear movement. A portion of a drive cable is wrapped around a drive shaft. Rotation of the shaft causes the wrapped cable portion to take up a perpendicularly extending cable portion on one end, and feed out a perpendicularly extending cable portion on the other end. As it does so, the wrapped cable portion moves axially along the drive shaft. The diameter of the drive shaft and its site of rotation determine the speed of take-up, and feed out. Axial movement of the wound portion on the drive shaft is determined either by the pitch of the threads in a threaded section on the drive shaft, or the movement of control means on an externally threaded control shaft.

Abstract: A recirculating refrigeration system wherein a screw compressor receives vaporized refrigerant from the evaporators at its low pressure inlet and from a flash tank or receiver at an intermediate pressure inlet. Refrigerant which is not vaporized in the evaporators is trapped in a suction line accumulator from which it flows by gravity into a dump tank. The dump tank has a gas pressure connection to the compressor outlet or to the receiver or flash tank and a control valve is effective to introduce gas under pressure to the dump tank and force the liquid accumulated therein back into a receiver when it has risen to a predetermined level in the dump tank.

Abstract: A refrigeration system incorporating a compressor sub-system which provides a source of higher pressure gaseous refrigerant to force liquid refrigerant into the receiver when condensor pressure is reduced sufficiently below normal to prevent it accomplishing the same purpose. When condensor pressure is insufficient to force liquid refrigerant from a pilot receiver tank to the receiver tank liquid accumulates in the pilot receiver tank to a level where it actuates a control valve, introducing said higher pressure gaseous refrigerant to said pilot tank and forcing liquid out. While condensor pressure is sufficient to the task, as is normally the case, the higher pressure gaseous refrigerant is received directly by the condensor.