preventing any contraction or expansion of the metals. 2. It prevents the oil from vaporizing in the crank case. 3. The bearings are kept at a uniform temperature and prevented from overheating. 4. It keeps the stuffing box in excellent condition at all times. 5. It gives additional condensing surface on the receiver. 6. Provides a direct outlet to the sewer in case of leaks. <Callout type="important" title="Important">The expansion valve is of the diaphram pressure type.</Callout> It is screened to prevent dirt and scale from getting to the valve seat. The automatic control consists of a small 1/50 hp. motor which is reduced in speed by worm gears. One of these is directly connected to a rotating shaft, which contains on one end the rotary switch with three terminals corresponding to the three terminals on the thermostat, and the two terminals for the power motor switch. On the one end is fixed the water cock for regulating the flow of water to the condenser shell. As both switches and water valve are firmly fastened to the same shaft and rotate at the same time, it is plainly evident that both water and current must be on or off at the same time. If the water supply fails, a diaphram pressure switch directly connected to the water line cuts off the motor instantly. <Callout type="risk" title="Risk">If the pressure falls below a safe margin, the motor will not start again until the water pressure has been again restored to normal.</Callout> With alternating-current, a repulsion-induction motor is used, continuous duty type. With direct current, a compound wound continuous duty motor must be used. The size furnished is Ys horse power, 1200 r.p.m. <Callout type="tip" title="Tip">The machine is rated at 250 pounds of refrigeration.</Callout> 206 HOUSEHOLD REFRIGERATION Cooke Refrigerating Machine. — The Cooke Household Re- frigerating Machine is manufactured by Mr. George J. Cooke, Sr., of Chicago, Ilhnois. The compressor is of the single cylinder, vertical, single-acting type. A cross-section and longitudinal section is shown in Fig. 57. The cylinder diameter is 1^4 inches and the stroke is 13/2 inches. The compressor operates at 450 r.p.m. normally. The suction valve is of the port type ; the discharge valve is of the disc plate t3-pe. The compressor crank shaft and connecting rod are provided with ball bearings to reduce the friction losses to a minimum. The crank shaft is packed by means of the patented seal ring. The packing is submerged in oil while the machine is in operation. A small but heavy flywheel is keyed to the crankshaft. A glass-covered observa- tion port is provided opposite the end of the crank shaft for observing the condition of the lubricating oil. The condenser consists of a spiral pipe coil around the com- pressor cylinder, as shown by Fig. 57. An exterior casing en- closes the water circulation for the condenser and water jacket for the compressor cylinder. The ammonia gas is discharged COMPRESSION REFRIGERATING MACHINES 207 into the top of the spiral condenser coil and the liquefied am- monia drains out of the bottom of the coil into a combined ammonia receiver and oil trap which is cast integral with the compressor frame. An automatic oil return valve is used. The compressor is driven by means of a ^ hp. electric motor running- at 1,750 r.p.m. It is belted to the compressor by a "V" type belt. Proper belt tension is obtained by mount- ing the motor upon a hinged base. The compressor and motor are mounted upon a substantial cast-iron base. The compressor and motor unit is 20 inches long, 10 inches wide, and 15 inches high overall and weighs 150 pounds. The cooling element consists of a brine tank containing direct expansion coils. Trays are provided for the freezing of seventy-two 1^ inch ice cubes for table use. The expan- sion valve is of the angle standard orifice type, protected from foreign matter by a small strainer in the lic^uid line just ahead of the valve. It is located just above the brine tank. <Callout type="beginner" title="Beginner">The machine is self-contained, simple in construction, and all parts are readily accessible.</Callout> The operation of the machine is positively and automatically controlled by means of a mer- coid electric switch which is actuated by a thermostatic ele- ment submerged in the brine of the main tank. The controls may be adjusted to maintain any reasonable temperature in the refrigerator. The condenser water supply is controlled by a diaphram valve which is actuated by the condenser pressure. The total charge of the ammonia in the system is said to be 3y2 ounces. <Callout type="gear" title="Gear">The capacity of the machine, it is claimed, is 350 pounds of ice melting effect per day.</Callout> It may be installed on or adjacent to any refrigerator having a maximum of 35 cubic feet. The refrigerating machine has in connection with it an ice cream freezer of the domestic size. This is mounted on the side of the refrigerator. The ice cream freezer has a brine tank containing a submerged spiral direct expansion coil. Operation of the freezer requires only a one-quarter turn of a hand lever located just above the main brine tank. It is claimed that one gallon of ice cream may be frozen in ten to fifteen minutes.
Key Takeaways
- The Cooke Refrigerating Machine uses a single-cylinder, vertical compressor with ball bearings for minimal friction loss.
- It features an automatic control system that ensures water and power are synchronized.
- The machine is self-contained and simple to operate.
Practical Tips
- Regularly check the lubricating oil level in the observation port to ensure proper operation.
- Maintain a consistent water supply pressure to prevent motor failure.
- Adjust the thermostat settings according to your specific cooling needs.
Warnings & Risks
- Be cautious of potential ammonia leaks, which can be hazardous if not properly contained.
- Ensure that all parts are correctly assembled and sealed to avoid refrigerant loss.
- Do not attempt repairs without proper training or risk injury from high-pressure systems.
Modern Application
While the Cooke Refrigerating Machine uses ammonia as a refrigerant, modern survivalists can still benefit from understanding its principles of operation. The use of self-contained units and automatic controls remains relevant in emergency situations where space is limited and maintenance is crucial.
Frequently Asked Questions
Q: What type of compressor does the Cooke Refrigerating Machine use?
The Cooke Refrigerating Machine uses a single-cylinder, vertical, single-acting type compressor. The compressor operates at 450 r.p.m. normally and has ball bearings to reduce friction losses.
Q: How is the water supply for the condenser controlled in the Cooke machine?
The water supply for the condenser is controlled by a diaphragm valve that is actuated by the condenser pressure, ensuring proper cooling and preventing motor failure due to insufficient water flow.
Q: What is the capacity of the Cooke Refrigerating Machine in terms of ice melting effect per day?
The capacity of the Cooke Refrigerating Machine is claimed to be 350 pounds of ice melting effect per day, which can be installed on or adjacent to any refrigerator with a maximum of 35 cubic feet.