US2497903A - Refrigerating mechanism - Google Patents

Description

Feb. 2l, 1950 s. MUFFLY Rsmrcm'rmc uzcmmrsu .Filed oct. 9, 194s gmac/who@ Glan??? Muff/q #fall-P.

Patented Feb. 2l, 1950 UNITED STATES PATENT oFFlcE 2,491,903 aal-*aroaaamo MacnANlsM Glenn Mumy, spi-mman, ohio Application October 9, 1945, Serial No. 521,241

(ci. sz---ln` t l 3 Claims.

This invention relates to refrigerating mechanism and particularly to such mechanism as is employed to shift refrigerant now so as to shift refrigerating effect from one evaporator to another. This application relates to the same subject matter as my application of October 29, 1938 which resulted in U. S. Patent No. 2,359,780 which issued October 10, 1944. Reference is made to this issued patent for additional detalls of the herein disclosed mechanisms and their uses.

, An object of this invention is to provide a valve mechanism which is actuated by a metering device responsive to the volume of refrigerant vapor flowing through a portion of the system.

Another object is to provide such a valve mechanism with a timed actuating device, the length of the operating period of an evaporator being regulated by the mass of-vapor flowing therefrom.

A further object of this invention is to provide a valve mechanism within a refrigerant containlng portion of the system and driven independently of any external power source.l

A further object of this invention is to provide a valve timing mechanism which is responsive not only to the time and velocity of refrigerant flow but also to variations in the density of refrigerant vapor.

Other objects of the invention will become apparent from the following specification, the drawings relating thereto, and the claims hereinafter set forth.

In the drawings in which like numerals are used to designate like parts in the several views throughout: f l

Fig. 1 is a diagrammatic view of a. self-actuating valve mechanism designed to act in response to the velocity and density of refrigerant vapor flowing from evaporators.

Fig. 2 is a simplified arrangement of the elements seen inv Fig. 1. f A

Fig. 3 is a sectional view on the line rof Fig. 2.

The assembly seen in Fig. 1 here shown in a somewhat diagrammatic manner, illustrates the working of Figs. 2 and 3. The actuation of the valve is obtained independently of the starting and stopping of the condensing unit, being timed in relation to the density and volumev of refrigerant vapor passing to suction tube 59.

As seen in Fig. l the port of tube 61 is open into the gas-tight casing |44, and the gas must pass through orice |45 in the wall |45, which divides the casing |44 into two parts in a substantially gas-tight manner except for this port 2. |45. The Jet of gas striking vanes of the gaswheel |41 produces rotation of this gas-wheel so long as gas is being removed through the passage 59 by action of the condensing unit. The fan (gas-wheel) is mounted rigidly upon sleeve |45, which also carries pinion |45. Pinion |49 drives gear |55, which is rigidly connected with pinion |5|. This pinion drives another gear |55 and so on till the last pinion |5| drives gear |52, which is the same as gears |55 except that it is mounted on sleeve |53 instead of to Aanother pinion. Sleeve |55 carries crank arm |54 on which is mounted the point |55. Shafts |55 and |51 are fitted freely in all of the parts through which they pass, including the cross member |55 in which shaft |55 has a bearing and wall |45 in which shaft |5'lhas a bearing. Sleeves |45 and |55 are free to rotate upon their respective shafts as well as in their respective bearings in wall |45 and cross-member |55, respectively.

The gear ratio and the gas-driven wheel |41 are designed to produce a veryslow rotation of sleeve |53 on the order of one revolution per hour for average running conditions of gas density and velocity in the system for which the assembly is designed. The compression spring |55" is fltted with a cupped retainer at each end and held between points |55 and |52', thus lbeing in position to hold` the rocker |54' at one or the other of its two extreme positions, closing the port of 55 or 51 as the case may be. The circular travel of point |55 is onv a radius such that the rocker |54 is caused to snap to the opposite position twice in each full rotation of sleeve |55. Thus eachof the ports of passages 55 and 51 will be open into housing |44 alternately during aportion of a revolution of sleeve |55. As described in my earlier patent application above mentioned, this mechanism may be used to provide an ice-making period and an ice-freeing period for each of the two ice-maker evaporators. In that case the design is .such that the length of an ice-freezing period is ample to provide a satisfactory ice-freeing period of the same length on the opposite surfaces of the ice-maker.

Figure l is included for the purpose of showing the train of gearing more clearly than it can be shown in Figs. 2 and 3, which represent much more exactly the form of housing and arrangement of parts preferred in practice.' The gearing seen in Fig. 2 is arranged to perform exactly the same function as the gears in Fig. 1, as do the gas-wheel |41 and the orifice |45. The dividing wall |55 serves the same function as wall |45 of Fig. 1 and in addition is the sole support for the 3 gearing assembly. Wall |66 fits into the lower half |64 of the gas-tight housing and is retained bythe upper half |66 which is gasketed to |64 and secured together by means of screws and nuts, of which two are shown.

It is not necessary to trace the gearing between gas-wheel |41 and eccentric |61, but the gearing assembly |66 serves to produce approximately the same rate of eccentric rotation that we had of crank |54 rotation in Fig. 1. This eccentric acts upon the U-shaped arm |68 to move one end of the spring |06 iirst in one direction and then in the other so that it acts upon the point |62' and the valve rocker |04 exactly as before described. The slot in one side of the part |66 is non-symmetrically formed to produce about the same ratio of movement for snapping in each direction. The stop |69 attached to part |66 retains the arm |68 and prevents spring I from moving it too far in either direction prior to assembly of parts |64 and |65 to each other.

The type of valve mechanism illustratedV by Figs. 1 to 3 inclusive is suitable for use in connection with any type of condensing unit, either intermittent or continuous in operation and of either the compression or absorption type, including adsorption systems and three-fluid systems. It has no external connection with a moving part and exposes no delicate bellows or diaphragm to the refrigerant. The cycling of the evaporators is thus independent of the cycling of the condensing unit. It may be desired to regulate the operation of the condensing unit to stop it when a maximum supplyof ice has'been accumulated or a minimum low temperature attained but this stopping and starting need not be synchronized with the cycling of evaporators during one running period. A thermostatic` control may be made subject to cabinet air temperature independently of evaporator temperature, providing a more uniform cabinet air temperature control than is possible with any of the conventional thermostatic controls.

On account of the very light load on the fastmoving parts and the very slow motion of the more heavily loaded parts, it is possible to operate the valve mechanisms with practically no lubrication, but some lubricationis obtained from the refrigerant itself and more from the oil which circulates with the refrigerant in most systems. The outlet at 66 may be so located that some oil is trapped within the gear housing in position for one or more of the gears to dip in this oil. Such an arrangement is shown in Fig. 1. Bearings of Figs. 2 and 3 may be hardened or jewelled or made of a self-lubricating material such as a graphite-impregnated bronze, or they may be of ball or roller types which will operate under these light loads with no lubrication.

What is claimed is:

1. In a refrigerating system, means forming a refrigerant circuit including alternate paths for refrigerant flow, valve means for diverting refrigerant ow from one to the other of said paths, and mechanical means driven by refrigerant owing through said system for actuating said valve means at timed intervals.

2. In a refrigerating system, means forming an enclosure adapted to contain a refrigerant, a rotary member driven by the ilow of refrigerant within said enclosure, and a control device actuated by said rotary member at a frequency of operation much lower than the frequency of rotation of said member.

3. In a refrigerating system, a refrigerant, means forming a ow circuit for said refrigerant including an enclosure through which said refrigerant ilows during operation of said system, a rotary member within said chamber adapted to be driven by the flow of said refrigerant, and means actuated by said member to change the path of said refrigerant in its flow through a portion of said system.

GLENN MUFFLY.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 1,321,230 Miles Nov. 11, 1919 2,359,780 Muiiiy Oct. 10, 1944 OTHER REFERENCES Double Patenting, by Stringham.

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