US3196631A

US3196631A - Portable refrigeration chest

Info

Publication number: US3196631A
Application number: US204989A
Authority: US
Inventors: Kenneth D Holland
Original assignee: Individual
Current assignee: Individual
Priority date: 1962-06-25
Filing date: 1962-06-25
Publication date: 1965-07-27
Anticipated expiration: 1982-07-27

Description

July 27, 1965 K. D. HOLLAND 3,195,631

PORTABLE REFRIGERATION CHEST July 27, 1965 K. n. HOLLAND 3,196,631

PORTABLE REFRIGERATION CHEST 8 Sheets-Sheet 2 Filed June 25, 1962 ulllll BIHLZ July 27, 1965 K. D. HOLLAND 3,196,631

PORTABLE REFRIGERATION CHEST Filed June 25, 1962 8 Sheets-Sheet 3 INVENT OR.

July 27, 1965 K. D. HOLLAND VPORTABLE REFRIGERATION CHEST 8 Sheets-Sheet 4 Filed June 25, 1962 July 27, 1965 K. D. HOLLAND PORTABLE REFRIGERATION CHEST 8 Sheets-Sheet 5 Filed June y25, 1962 July 27 1965 K. D. HOLLAND 3,196,631

PRTABLE REFRIGERATION CHEST Filed June 25, 1962 8 sheets-sheet e Alf/ i/%JZZ, 7.45%@ Z4@ July 27, 1965 K. D. HOLLAND PORTABLE REFRIGERATION CHEST 8 Sheets-Sheet '7 Filed June 25. 1962 July 27, 1965 K. D. HOLLAND PoRmsLE REFRIGERATION CHEST Filed June 25, 1962 8 Sheets-Sheet 8 United States Patent Oce 3,196,631 Patented July 27, 1965 3,196,631 PORTABLE REFRIGERATIN CHEST Kenneth D. Holland, '707 lroortree Road, Pacific Palisades, Calif. Filed .lune 25, 1962, Ser. No. 204,989 1 Claim. (Cl. 62-238) This invention relates to portable refrigeration chests.

More particularly, it relates torefrigerating systems having a single circulating fluid for both power and refrigerating loops. The invention also relates to novel apparatus for powering such refrigeration apparatus.

' The conventional campers food chest is normally dependent upon the use of ice to maintain a low temperature within the interior of the chest to preserve foodstuffs over a long period of time. Such chests normally are insulated on their exterior walls and provide an internal cavity or well in which a supply of crushed ice is dispose-d. The ice well includes a secondary well in which the chilled food is stored. Such conventional food chest are restricted in their capacity depending upon the length of time the particular food contained therein is to be preserved. lf the individual using the conventional campers chest contemplates -an overnight or weekend camping trip, then a relatively small amount of ice will maintain the food in a safe condition for the desired period. On the other hand, if the conventional chest is required to preserve food over a long period of time, then the greater amount of ice is required and the actual amount of food which may be disposed in the chest is reduced. Further, such conventional ice chests are heavy and are difficult to transport because of the large amounts of ice which are required. Another disadvantage of the conventional campers chest is that as the ice melts, the water produced thereby is retained in the chest and can, in many instances, damage the food which it is sought to preserve by the use of such chest.

In order to avoid the undesirable characteristics of the conventional chest, recent developments in campers equipment include a food storage chest wherein a refrigerated brine or coolant-lled insert is disposed interiorly of the insulated walls of the chest. These brine containers are prefrozen and inserted into the chest prior to insertion of the foodstuiis into the chest. The advantage of such removable brine containers is that as they thaw, the liuid does not intermix with the food. Also, a much lower temperature is achieved such that a greater quantity of food may be stored for a longer period of time.

Both the conventional ice chest and the removable brine container-type chests are subject to the disadvantage that they are limited in the length of time during which they provide refrigeration of the contents of the chest. When such chests are to be used over a protracted period of time, then either ice or a means for refreezing the brine containers must be available. In many camping expeditions, such availability of ice is restricted.

This invention provides a food storage chest which has its own refrigerating system. The refrigerating system is powered by a campfire or the like such that the availability of electrical power is not a condition precedent to successful operation of the chest. The power unit operating the refrigeration portion of the chest is removable from the chest such that the weight of the chest can be reduced during transportation of the device. Furthermore, the removability of the power unit provides for an and apparatus for refrigeration.

` the bores of the iirst and second pairs of bores.

auxiliary power supply at the camping location since the invention also contemplates the provision of an electrical power generator in conjunction with the refrigeration power unit. Such a generator is useful to power electric lights, radios, electric razors, and the like.

Generally speaking, the invention comprises a refrigeration system using a single circulating fiuid medium. The uid medium circulates through a power circuit and also through a refrigeration circuit. A portion of the flow path of the circulating medium through the power circuit is in common with a portion of the How of the circulating medium through the refrigeration circuit.

More specifically, the invention comprises a system The system uses one circulating fluid medium having a gaseous phase and a liquid phase. The apparatus of the system includes a rst heat input means for changing a portion of the circulating fluid medium from the liquid phase tothe gaseous phase thereof. A second heat input means is provided wherein the remainder of the circulating iiuid medium is changed from the liquid phase to the gaseous phase thereof. A prime mover is provided together with uid medium duct means connecting the `irst input means and the prime mover. A heat dissipating means is provided wherein the fluid medium is changed from the gaseous phase to the liquid phase. The apparatus of the invention further includes a gaseous phase compressor means operated by the prime mover and connected for fiow of the fluid medium to the outlet of the second heat input means. Additional luid medium duct means connect the compressor means and the outlet of the prime mover to the heat dissipating means. A pump means operated by the prime mover is provided for circulating the liquid phase of the first portion of the duid and is connected between the heat dissipating means and the first heat input means. Moreover, the invention also includes a pressure reduction means for the liquid phase of the remainder of the iiuid, the pressure reduction means being connected between the heat dissipating means and the second heat input means. This apparatus provides fluid flow path common to the power and refrigerating fluid medium flow paths or loops of the refrigeration system.

In terms of the apparatus provided for practicing the refrigeration system, the invention further comprises a modular power unit operable by compressed gas from the first heat input means. The power unit comprises a housing deiining a central elongate cavity therein. First and second pairs of oppositely disposed bores are provided in the housing opening to the cavity and extending to closed ends spaced from the cavity. A beam member is longitudinally disposed inthe cavity and has connected thereto a plurality of pistons, each of which extends from the beam member into reciprocal engagement with one of Compressed gas inlet and outlet ducts communicate with the bores of the first pair at the closed ends of the bores. Valving means are provided in these inlet and outlet ducts for alternating the communication of the first bores between the inlet and outlet ducts such that when one of the bores of the first pair is associated with the inlet duct, the other of the bores of the rst pair is associated with its outlet. The power unit further includes fiuid duct means communicating with the second pair of bores for the introduction of a fluid to be pumped into and out of these second pair of bores. The apparatus provides for alternating communication of the compressed gas inlet and outlet ducts with the first pair of bores to reciprocate the beam member laterally of the cavity. This reciprocation of the beam member pumps -fluid introduced into the second pair of bores.

These and other features and objects of the invention will be more clearly understood by reference to the following detailed explanation and description of .the invention take in conjunction with the accompanying drawings, wherein;

FIGURE 1 is a schematic representation of the power loop and refrigerating loop of the refrigeration system;

FIGURE 2 is an enlarged rear elevational view of the modular power unit;

FIGURE 3 is a cross-sectional elevation of the modular power unit taken along line III-III of FIGURE 4;

FIGURE 4 is an enlarged cross-sectional plan View of the valving mechanisms for the bores of the modular power unit taken along line IV--IV of FIGURE 3;

FIGURE 5 is an enlarged fragmentary elevation of the means for transferring reciprocal to rotary motion for operation of the valving mechanism of the power piston element and is taken along line V-V of FIGURE 2;

FIGURE 6 is an enlarged cross-sectional elevation of a second'preferred embodiment of the invention in illustrating an electrical generator;

FIGURE 7 is a plan vieu/with parts broken away, of the boiler or first heat input means of the refrigeration apparatus; l

FIGURE 8 is an end elevational view, with parts broken away, of the boiler;

FIGURE 9 is a cross-sectional elevation of the umtary refrigeration chest of this invention;

FIGURE 10 is a schematic representation of the operable portions of the device when the modular power unit and its associated apparatus is removed from the food storage chest for operationv as an electrical generator and auxiliary power supply; and

FIGURES 11, 12 and 13 illustrate an alternate embodiment of the power cylinder valve.

l Referring to FIG. l, a schematic representation of the common leg fluid iiow scheme between the power loop and the refrigerating loop of the apparatus is illustrated. A preferred embodiment of the invention has a power iluid medium flow path or loop 12 and a refrigerating loop 13 having a common fluid iiow path or leg 14 for a single circulating fluid medium. The circulating fluid medium has a gaseous phase and a liquid phase, and, as an eX- ample, may be ammonia, Freon in any of its forms, or any other useful refrigerant fluid. The power loop 12 includes a boiler or heat input means 15 illustrated more completely in FIGS. 7 and 8 and described in greater detail below. The boiler 15 is powered by exposure to a fire, such as a campfire or the like, and has an inlet and outlet. The outlet of the boiler 15'is connected to a duct 16'for circulation of the gaseous phase of the iiuid medium. Duct 16 extends from the boiler 15 to the inlet of a modular power unit 17. A'pump 18 is also provided in the power loop 12 and is connected for operation to the vmodular power unit 17. In a preferred form of the invention, the pump 18 is a portion of the modular power unit 17. The outlet of pump 18 is connected by a duct 19 to the inlet of the boiler or generator 15 and conducts a portion of the circulating uid medium in its liquid phase from pump 1S to boiler 15. Check valves 20 and 21 are provided upstream and downstream of pump 18. As illustrated in FIG. 1, the duct 19 includes the downstream check valve 21.

In the common How leg 14 between the power and refrigerating

power loops

12 and 13, respectively, a heat exchanger or condenser 23 is installed. Preferably, condenser 23 comprises a plurality of tubes through which the fluid medium passes. The tubes are exposed to ambient air which circulates around the tubes to carry off heat released as the fluid condenses inside the tubes. A

duct 24 extends from the outlet of the modular power unit 17 and communicates upstream of the heat exchanger 23 with a duct portion 14A in the common ow leg 14. A similar duct or piping element 14B is connected to the outlet of the heat exchanger or condenser 23 and communicates with a duct 25, including the upstream check valve 21) which extends to the pump 18.

The refrigerating loop of the circulation system illustrated in FIG. 1 includes an expansion device 26 included within the extent of a duct 27 extending from common ilow duct 14B to the inlet of an evaporator 28. The evaporator 2S is similar to the conventional refrigeration evaporator and has an outlet to which is connected another duct 29 extending to the inlet of a compressor 30. As illustrated in FIG. l, the compressor 36 has first and second stages 31 and 32, but it is within the scope of this invention that the compressor 30 may be a single stage compressor or may have three or more stages. As illustrated in FIG. 1, the compressor 3@ is operably connected.

to the modular power unit 17. In a preferred form of the invention the compressor is included Within the housing of the modular power unit 17. To complete the fluid flow circuit of the refrigerating loop, a duct 33 extends between the outlet of the compressor 31) to the upstream portion 14A of the common flow leg 14.

In the preferred system illustrated inV FIG. 1, both the gaseous and the liquid phases of the -single circulating fluid medium are present. The boiler or generator 15 serves to change the liquid phase of the circulating medium into the gaseous phase. This gaseous phase is transported by duct 16 to the power unit 17 for operation of the power unit. Such operation of the power unit drives the pump 18, the compressor 36 and a fan 34 which is mounted to the heat exchanger 23 to force ambient air through the heat exchanger 23 to enhance the operation of the exchanger. The gaseous phase of the circulating fluid medium introduced into the power unit 17 is at a high temperature and pressure but is exhausted from the power unit through duct 24 at reduced temperatures and pressures. This used portion of the circulating fluid medium is then introduced into the heat exchanger where it is converted from the gaseous phase to the liquid phase. Simultaneously with introduction of the gaseous phase from the power unit into the heat exchanger, the compressor 30 discharges the circulating uid medium in its gaseous phase into the upstream portion 14A of common leg 14 for introduction into heat exchanger 23. This W scheme provides that the portions ofthe gaseous phase introduced from power unit 17 and compressor 30 are intermixed in the upstream leg 14A; Similarly, in the outlet or downstream leg 14B from heat exchanger 23, a portion of the'liquid phase emerging from the condenser 23 is introduced in the duct 25 for ow to and through pump 18. In pump 18,.the pressure of the liquid phase 1s raised for introduction into generator 15 according to the process described above. The remainder of the liquid phase of the circulating medium not passed through pump 18 is passed through duct 27 and expansion valve 26 into the evaporator 23. In the evaporator 23 the liquid phase flashes or expands into the gaseous phase and in the process absorbs heat from the surroundings of the evaporator. Following the expansion of the liquid phase of the circulating medium into the gaseous phase in evaporator 23, the gaseous phase of the remainder of the circulating Huid is passed through the compressor Sti prior to introduction into the upstream portion 14A of common fluid ow leg 14.

The ow of the circulating medium through both the power and refrigerating

loops

12 and 13, respectively, is on a continuous flow basis. A presentation of a heat balance associated with a particular embodiment of the invention is presented in Table 1. The data of Table l is based upon the use of anhydrous ammonia as the circulating uid medium.

l-HEAT BALANCE OF FIG. 1`

TABLE Heat Wt. flow Tempera Enthalpy transfer 1b./hr. ture "F. P.s.i.a. B.t.u./ll

B.t.u.lhr.

Boiler 6, 355 12. 19 Inlet to Power Unit 17- 12. 19 251 750 691 Outlet of Power Unit 17 12.19 120 250 641 Inlet to Condenser 14. 44 157 250 762 Condenser 1 14. 44 Outlet of Condenser. 14. 44 110 247 167 Inlet of Boiler 12. 19 110 76() 170 Inlet of Evaporator-. 2. 0 31 167 Evaporator 2. 25 Outlet of Evaporator 2. 25 0 29 612 Inlet of 2d Stage Compressor 2. 25 `184 85 706 Outlet of Compressor 2. 25 415 250 832 1 Fan consumes 74 Btu/hr.

Referring to FIGS. 2, 3, and 4, the modular power unit 17 is illustrated. Power unit 17 includes a housing 35 having upper and lower halves or

portions

36 and 37, respectively. These housing portions have

mating surfaces

33 and 39, respectively, between which a gasket material 4t) made of Mylar or the like is disposed. A series of through bolts 41, extending through the

housing portions

36 and 37, secure the

portions

36 and 37 and the gasket 46 together.

As illustrated in FIG. 3, each

housing portion

36 and 37 has a recess formedtherein adjacent its respective mating surface. These recesses are such that when the

housing portions

36 and 37 are secured together, the

recesses dene an elongated cavity 42 within the extent of the housing 35. The cavity has spaced apart upper and lower walls 43 and 44, respectively. A plurality of bores grouped into pairs of bores 45, 46 and 47 are formed in the housing 35.

Bores

45A, 46A and 47A extend from the upper surface 43 of cavity 42 into the upper housing portion 36 to closed ends spaced adjacent from the upper surface 4S of the housing 35. Bores 45B, 46B and 47B extend downwardly from the lower surface 44 of cavity 42 and terminate in closed ends spaced from the underside or bottom 49 of housing 35. In addition to the

external surfaces

48 and 49 of housing 35, housing also has left and right sidewalls 5t) and 51 (as viewed in FIG. 2) and front and rear walls 52 and 53 defining a cubical configuration of housing 35.

Each of the bores of the pairs 45, 46 and 47 are axially aligned relative to one another with the axes of the bores being oriented vertically with respect to housing 35. An elongated beam member 54 is disposed in cavity 42 and is oriented parallel to the elongate extent of cavity 42. A plurality of pistons, arranged in pairs of pistons 55, 56 and 57, are connected to the beam 54.

Pistons

55A, 56A and 57A are disposed on the upper side of beam 54 and cooperate within bores A, 46A and 47A, respectively. Similarly, pistons 55B, 56B and 57B are disposed on the underside of beam 54 and extend downwardly into cooperation with bores 45B, 46B and 47B, respectively. Since all of the pistons are substantially identical, with only the lateral dimensions of each piston varying depending upon the dimensions of the cylinder in which the piston cooperates, only piston 56A will be described in detail.

Piston 56A has an elongated connecting rod portion 53 extending between aradially flanged lower end 59 and an integral piston head portion 60. The radially flanged end 59 is disposed adjacent beam 54. The piston head portion 60 has a diameter slightly less than the diameter of cylinder 46A. A peripheral groove 61 is formed in the vertical walls of piston 60 and receives an C-ring which functions as a piston ring to maintain sealing engagement with the walls of cylinder 46A.

A longitudinal hole 63 is formed coaxially through piston 56A from head 6) to the end portion 59. A countersunk or recessed well 64 is formed in the head portion 6) and opens toward the closed end of the cylinder 46A. A similar hole 65 is drilled through the beam 64 with the axis of hole 65 being as closefto concentric with the axis of

cylinders

46A and 46B as possible. A tie-rod 66, having a diameter along the major portion of its length less than the diameter of

holes

63 and 65, is provided to tie pistons`56A and 56B to the beam 54. The tie rod 66 has an enlarged head 67 which is engaged within well 64 of piston 56A when the rod 66 is passed through holes 63 of

pistons

56A and 56B and hole 65 in beam 54. The lower end of rod 66 has a threaded portion upon which a nut 68 is engaged to secure the pistons to the beam 54. Resilient gaskets are disposed between the enlarged head 67 and nut 68 and the respectiveV pistons to provide secure seating and engagement between the tie rod 66 and the pistons 56. V

A plurality of bearing spheres 69 are mounted between the radially flanged portions 59 of each piston and the beam 54. Preferably, the spheres are fabricated of Teflon polytetrafluoroethylene or some other resilient low-friction material, but it is also Within the scope of the invention that spheres 69 may be metallic. The spheres 69 nest in recesses provided in the radially anged portions 59 of pistons 56. A clearance exists between the diameter of the tie-rod 66 and the walls of holes 63l such that a small amount of lateral wobble relative to beam 54 is allowed between the pistons 56. This is desirable since during the manufacture of the modular power unit 17 (wherein the pistons 55, 56 and 57 are all ganged or coupled directly to beam 54) the tolerance limits permitted during manufacture may become additive. ln such a situation the pistons would be misaligned with the cylinders and would not be properly engagable within the cylinders 46 and 47 if the pistons 55 to 57 spacing between the axes of the

cylinders

45A, 46A and 47A may be different than the spacing between the corresponding pistons SSA, 56A and 57A as well as between the holes 65 in beam 54 for each pair of pistons. The

' lateral wobble provided by tie-rods 66 and spheres 69 allows for minute adjustments in the position of the pistons to accommodate for tolerance of build-up during manufacture of the device.

The cylinders 45A and 45B and pistons 55A and 55B comprise the power or prime mover portion of the modular unit 17. The prime mover is a double acting reciprocating piston engine. A valve chamber 70 is provided within each of the

housing portions

36 and 37 between closed ends of the respective cylinders 45A and 45B and the exterior surfaces 4S and 49 of housing 35. Since the valve mechanisms for the power pistons 55A and 55B are substantially identical, only the structure of the valve mechanism for piston 55AV is illustrated and is discussed in detail. This discussion and explanation will suffice to explain the structure an operation of the valve for 71 is a slotted duct having its elongate extent parallel to the axis of the valve cylinder or chamber 70. Compressed gas inlet and outlet ducts 72 and 73, respectively, are provided from the front surface 52 of housing 35 and extend into communication with the Valve chamber 70 at horizontally spaced apart positions of chamber 70. The ducts 72 and 73 have internally tapped portions adjacent the front wall 52 of housing 35 into which pipe fittings or tubing connections are engagable. A rotary valve member 75 is positioned within the valve chamber 70 and has a blade portion 76 disposed between cylindrical barrel-like end portions 77 and 78. An O-ring 79 is provided peripherally of the barrel portion 78 and engages the side walls of valve chamber 70. An annular recess 80 is provided in the walls of the valve chamber 70 and a resilient snap-ring or retainer 81 is engaged therein to secure the valve 75 within the valverchamber 70. The valve 75 is rotatable within the valve chamber 75 and oscillates angularly between two, blade positions oriented approximately 90 apart from one another.

As illustrated in FIGS. 2 and 4, the valve chamber 70 opens to a recess 82 provided in the upper rear portion of the housing 35. An elongated shaft 83 extends from the barrel portion 78 of valve 75 into recess 82. Shaft 83 is disposed coaxially with the valve 75 and has a clevis yoke 84 secured to its free end within recess 82. The yoke 84 has a pair of parallel arms 85 and 86 extending laterally therefrom into recess 82. Each of these arms 85 and 86 has a longitudinally oriented slot 87 formed Itherein. Cyclic angular displacement of the valve blade 76 through an arc of about 90 is impressed on blade 76 by connection of the shaft 83 to a reciprocating rod 88 having a tang portion 89 disposed between the spaced apart arms 85 and 86 of the clevis yoke 84. The connection between the tang 89 and the yoke 84 is by a pin 90 passed through the tang portion 89 and engaging the slots 87 in the yoke arms 85 and 86. Reciprocation of the rod 88 is by connection to a rotating fly-wheel through apparatus to be described below.

A hole 92 is formed through the upper portion 36 of housing 35 from the upper surface 48 into the cavity 412. Hole 92 accommodates a reciprocating rod 93 which is secured to beam 54 by a bolt or set screw 94 in the central portion of beam 54. First and second enlarged diameter

annular portions

95 and 96 are formed in the housing portion 36 adjacent the housing upper surface 48. An O-ring 97 is secured in an annular groove 98 of shaft 93 to seal shaft 93 tothe confines of the hole 92 and to serve as a bearing for shaft 93.

As illustrated in FIGS. 3 and 6, a rotatable fly-wheel 100, having a cam portion 101 and a gear portion 102, is mounted to the upper surface 48 of the housing 35. Fly-wheel 100 has a stub shaft portion 103 extending from its under surface into engagement with the

annular recesses

95 and 96 of hole 92 (see FIG. 6). A journal bearing 104 is provided in the smaller diameter annular portion 95 of hole 92 and engages the lower end of stub shaft 103. Preferably the journal bearing 104 is fabricated from Teflon plastic, however leaded brass or any other suitable journal bearing material may be used. A spring retainer ring 105 secures a thrust bearing collar 106 to the stub shaft 103 within the extent of the larger annular recess 96. The collar 106 is spanned by a pair of annular thrust bearing rings 107 and 108 also fabricated preferably from Teflon and fixed within the annular recess 96.

Attop plate or bracket 110 is secured to the upper surface 48 of housing 35 and has an aperture 111 therein through which the stub shaft 103 of fly-wheel 100 extends. Aperture 111 has a Teflon sleeve 112 shrunk into its extent; the sleeve 112 closely journals the stub shaft 103. Au aperture or hole 113 is drilled radially through the stub shaft 103 within the extent of the porl '8 tion bounded by sleeve 112. Hole 113 extends into communication with a hole or bore 114 formed axially of y-wheel 100. The reciprocating shaft 93 secured to the cross-beam member 54 reciprocates within the y-wheel bore 114. The upper end of shaft 93 has a circumferential groove 115 therein, which, if developedonto a planar surface, would trace a substantially sinusoidal curve of the type indicating harmonic motion. The developed prole of groove 115 is such that it is the graphic representation of the mathematical transformation function between the nature of reciprocation of rod 93 and uniform rotational motion of flywheel 100.

A pair of balls or spheres 116 are engaged within the lateral hole 113 of fly-wheel shaft 103. The innermost one of these balls is located so as to span the gap between the fly-wheel 100 and the groove 115 formed in the upper end of the reciprocating shaft 93. Since ily-wheel 100 is fixed from axial movement by the thrust collar 106 engaging the thrust bearings 107 and 108, reciprocatory motion of the shaft 93 is transformed into uniform rotaJ tional motion of the ily-wheel 100 as the sphere 116 engages groove 115. If desired, a pin may be used in place of balls 116.

It was mentioned earlier in this description of the invention that the valve associated with the inlet and outlet ducts 72 and 73 of cylinder 45A was regulated by the rotation of y-wheel The cam portion 101 of fly-wheel 100 has a control camming groove 120 formed around its periphery (see FIGS. 2, 3 vand 5). j The groove 120 has a lower portion 121 and an upper section 122 joined together by transition portions 123 of the groove 120. The

control portions

121 and 122 of cam groove 120 are parallel to one another and are disposed parallel Ito the upper surface 48 of housing 35. The reciprocating rod 88 connected to the clevis yoke 84 of power piston valve 75 extends into a recess 125 formed in Athe rear side 53 of housing 36 above the parting line 38. In the vicinity of the recess 125, the reciprocating rod 88 is bent into a horizontal portion 126 lying transversely of the recess 125. The rod 88 is then bent back parallel to itself in a vertical portion 127 which extends upwardly through the upper housing portion 36 and through the top plate to terminate in an end portion i 128 adjacent cam portion 101 of ily-wheel 100. A laterally extending pin 129 is fixed to the projecting end 128 of rod 88 and extends from rod 88 into engagement with the camming control groove 120 in fly-wheel 100. Rotary motion of fly-wheel 100 causes the rod 88 to reciprocate as the pin 129 maintains contact between the sides or walls of groove 120.

Groove 120 has a preselected configuration and is disposed in a predetermined orientation relative to the flywheel 100. This orientation is correlated to the position of groove formed in the upper end of reciprocatory rod 93. The phase relationship between grooves 115 and is such that as the beam 54 nears one limit of its motion laterally of the elongate extent of cavity 42, the blade 76 of valve 75 is caused to move about 90 from the position it maintained just previously to the angular displacement of the blade. The exact relationship and method of operation of the valving mechanism will be referred to following the explanation of the ducting for the inlet and outlet of compressed gas to the power piston cylinders 45A and 45B.

It was mentioned previously that the valving mechanism for the power piston cylinder 45B was substantially identical to valve 75 associated with the power piston cylinder 45A. The actuation of the valve for cylinder 45B is through the mechanism of a reciprocating rod 130 (see FIG. 5) and a clevis yoke similar to that illustrated in FIGS. 2 and 4. Rod 130 extends through the upper and lower housing portions 36 into a recess disposed adjacent the end of the valve associated with the lower cylinder 45B. In the case of the lower cylinder 45B, however, the recess corresponding to recess 82 is disposed on the front side 52 of the housing 35. Furthermore, the reciprocating rod 130 does not have the return bend configuration illustrated with the reciprocatingl rod 88 illustrated in FIG. 2. Rather, the rod 130 is straight between its upper end 131 exteriorly of the upper portion of housing 35 and the lower clevis yoke. The reciprocatory rod 130 associated with the lower power piston cylinder 45B is disposed diametrically opposite the rod SS relative to the axis of rotation of the ily-Wheel 109. Rod 13) is engaged with the controlrcamming groove 120 in ily-wheel 11i by means of a pin 132 extending between the upper end 131 of rod 1341 and the coniiines of groove 126.

Each of the power piston cylinders 45A and 45B has associated therewith a pair of compressd gas ducts. These ducts are the inlet and outlet ducts 72 and 73, respectively. The piping for these ducts of the lower power piston cylinder 45B is illustrated in FIG. 2. A manifold 135 is located adjacent the right sidewall 51 of the power unit housing 35. A duct 136 extends from the manifold 135 to theinlet duct 72 associated with the lower power piston cylinder 45B. A second duct 137 extends from the manifold 135 to the duct 72 leading to the valve chamber 70 of power piston cylinder 45A. A second manifold 133 is provided adjacent theleft sidewall t? of housing 35. A duct 139 extends from manifold 133 to the outlet duct leading to the lower cylinder 45B. A second duct 140 extends from manifold 138 into communication with the passageway 73 formed in housing member 36 and leading from the valve chamber 70 of cylinder 45A. Having reference to the schematic diagram of FIG.'1, theV first manifold 135 is connected to the duct 16 leading from the boiler or first heat input means 15 in the power loop 12. The second manifold 138 is connected to the duct 24 communicating with the upstream leg 14A of the common flow path 14 existing between the power loop 12 and the refrigerating loop 13.

As was mentioned previously, a suitable circulating fluid medium for use in the refrigerating system of this invention is anhydrous ammonia. The ammonia is changed from its liquid phase to its gaseous phase in the boiler 15. The gaseous phase is provided in duct 16 at an elevated .temperature and pressure. This high energy ammonia is used to operate the prime move-r pistons 55A and 55B. As illustrated in FIG. 3, the blade 76 of valve 75 for cylinder 45A is disposed in the condition whereby the inlet duct 72 is in communication with cylinder 45A. In such condition the pis-ton 55A is driven downwardly of the cylinder 45A' to cause the beam 54 to reciprocate transversely of the cavity 42. In view of the mechanical connection of the pistons to beam 54, as explained above, the piston 55B is caused to move downwardly in cylinder 45B and ammonia gas, which previously was used'in a power stroke in cylinder 45B, is exhausted from the cylinder. In order for the spent ammonia to be exhausted from cylinder 45B, the blade of the valve associated with cylinder 45B is oriented whereby communication exists between the cylinder 45B and the outlet duct from the cylinder. As the beam 45 rcciprocates or moves downwardly of cavity 42 according to the above process, the y-wheel 1d@ is rotated by interaction between ball 116 and the groove 115 in reciprocatory shaft 33. During the downstrolre of piston 55A, blade 76 is indexed to a dwell position over aperture 71 whereby the intaken ammonia expands. As the piston 55A nears the downward :limit of its travel, the ily-wheel '1110 rotates such that the pin 129 governing reciprocatory motion of rod 88 moves to the upper cam groove portion 122. This movement actuates the Valve member 75 such that it is vindexed through the remainder of its approximately 90 arc 0f movement (in a counterclockwise direction as viewed in FIG. 3) and the exhaust or outlet duct 73 is brought into communication with cylinder 45A through the slotted aperture 71. Simultaneously, with this indexing of the valve for cylinder 45A, a.90 indexing occurs with the valve for cylinder 45B whereby the outlet duct is closed from communication with cylinder 45B and the inlet duct is engaged. When such reversal of valve condition occurs, the piston 55B is subjected to the energy of the incoming ammonia` and beam 54 is caused to move upwardly of cavi-ty 4Z. During this process piston 55A expels the spent ammonia present in cylinder 45A.

The general schematic diagram of the refrigeration system (FIG. 1) includes a compressor 3i) having a first stage 31 and a second stage 32. In a preferred form of the invention, the compressors 31 and 32 are provided by the pairs of cylinders 46 and 47 cooperating with the pistons 56 and 57. The

pistons

56A and 56B correspond to the first stage compressor 31; the pistons 57A and 57B correspond .to the second stage compressor 32. Pistons 56 and 57 are coupled directly and operatively to the prime mover through the reciprocating beam 54. The valving mechanisms for the

cylinders

46A, 46B, 47A and 47B are substantially identical and therefore only the valving mechanism for cylinder 46A will be described in detail. This description will suice to describe the structure and operation of the valves for the remaining compressor cylinders.

In general terms each compressor cylinder comprises a reciprocating piston fluid pump. The valve mechanism for such a fluid pump is operated by the uid pump by the reciprocating motion of the piston. Each pump has a cylinder bore in a pump housing; the bore being closed at one end. The pump housing has first and second cavities therein spaced from the closed end of the cylinder bore; The housing further defines duc-t means extending from the cylinder bore to each of the cavities; such duct means may be referred to as the cylinder duct means. There may be one or more ducts in the cylinder duct means. A iiuid inlet duct communicates exteriorly of the pump housing to the first cavity adjacent the communication of the iirst cavity with the cylinder duct means. A iiuid outlet duct communicates from exteriorly of the pump to the second cavity adjacent the communication of the second cavity with the cylinder duct means. A valve plug is disposed in each of the cavities for reciprocating motion longitudinally of the cavity. Continuously open auxiliary passage means are provided in the housing from the cylinder bore to each cavity and from the second cavity to the outlet duct. The pressures developed in the cylinder bore are reflected in the cavities to induce reciprocation of the valve plugs for alternating communication between the inlet and outlet ducts and the cylinder bore.

Referring to FIG. 4, a recess 143 is provided in the housing right end wall 51 adjacent the upper or closed end of the cylinder 46A of the rst stage compressor 31. A pair of horizontally oriented parallel bores 144 and 145 are formed in housing 35 from the inner end of the cavity or recess 143. These bores 144 and 145 are spaced apartfrom one another transversely of the housing 35. The bore 144 extends farther inwardly from recess 143 than does bore 145. A plug 146 is xedly disposed in bore 144 adjacent the recess 143. A similar but shorter plug 147 is iixedly disposed in the outer end of the bore 145. Neither of the plugs 146 and 147 extends the full length of the respective bore; accordingly, a cavity is defined in the inner end of each of the bores 144 and 145. A retaining plug 148 is secured in the inner end of the recess 143 by a spring retainer clip 149 engaged in an annular recess or groove 150 intermediate the ends of the recess 1413. An O-ring 151 is provided between the inner end of plug 148 and the recess 143 to assure that the uid pumped in cylinder 46A will not leak from the housing 35. Y

A duct 153 is provided from the cylinder 46A into communication with the cavities provided by bores 144 and 145. As illustrated in FIG. 4, the duct 153 is coaxial of the cylinder 46A and extends from the closed end of the cylinder. The cavity deiined by the bore 144 is designated as cavity 154, while the cavity provided by bore 145 is designated as cavity 155, While the cavity provided by bore 145 is designated as cavity 155. Each of the cavities 154 and 155 is divided into lirst and second length portions of equal diameter. The first and second length portions of each cavity are of equal length. As illustrated in FIG. 4 the diameters of the cavities 154 and 155 are equal and the total lengths rof these cavities are equal. It is within the scope of this invention, however, that the diameters of cavities 154 and 155 may be diierent and that the total lengths of these cavities may be different. It is also within the scope of this invention that the geometrical orientation of the cavities `154 and 155 relative to the duct 153 communicating with the cylinder 46A may vary from the coplanar parallel orientation illustrated in FIGS. 3 and 4. To facilitate description of the valving apparatus for cylinder 46A, the right ends of the cavities 154 and 155 are referred to as the iirst lengths of these cavities while the inner or left-hand half lengths of the cavities are referred to as the second lengths of the respective cavities. 'Ihe cylinder duct 153 opens to the first length of the first cavity 154 and to the second length of the second cavity 155.

A pumped iluid inlet duct 157 communicates from the exterior of the pump housing to the cavity 154 adjacent the location at which the cavity 154 communicates with the cylinder duct 153. Similarly, a pumped fluid outlet du-ct 158 communicates from exteriorly of the pump housing 35 to the second cavity 155 adjacent the location where the cavity 155 communicates with the cylinder duct 153. In other words, the pumped rfluid inlet duct 157 and the cylinder duct 153 open to the rst length of cavity 154, and the pumped fluid outlet duct 158 and the cylinder duct 153 open to the second length of the cavity 155. The opening of the inlet duct 157 into cavity 154 extends to the outer or right Vend of the cavity 154. The portions of the inlet and outlet ducts 157 and 158 adjacent the exterior sides 52 and 53, respectively, of the housing 35 are tapped internally to accommodate suitable piping `fittings whereby tubing or piping for circulating the pump iluid may be connected to the pump housing 35. As illustrated, the inlet and outlet ducts 157 and 158 `and the upper end of the cylinder duct 153 are disposed along a common line transversely of the housing 35.

A valve plug is movably disposed in each of the cavities 154 and 155. As illustrated in FIG. 4, plug 159 is disposed in cavity 154 and plug 160 is disposed in cavity 155. Preferably, the plugs 159 and 160 have a length equal to one-half the total length of the respective cavities.

A pair o'f continuously open auxiliary passageways open from the closed end of cylinder 46A into the second lengths of each of the cavities 154 and 155. As illustrated in FIG. 4, a pair of `auxiliary passageways 161 open from cylinder 46A into the left end of cavity 154. One Vof the passageways 161 opens adjacent the extreme inner end of cavity 154. The passageways 161 are of considerably smaller diameter than the diameter of cylinder duct 153. Auxiliary passageway 162 opens from cylinder 46A to the left end of the cavity 155. An additional auxiliary or venturi passage 163 communicates between the extreme right end of cavity 155 and the pump iiuid outlet duct 158. The Venturi duct 163 is disposed at an angle relative to the outlet duct 158. and is oriented so as to be inclined toward the direction of iow of the pumped uid through duct 158. Duct 163 has a diameter considerably smaller than outlet duct 158.

Auxiliary passages

161, 162, and 163 are not Huid iiow ducts but rather are pressure equalizing passages.

It Was mentioned above that the valving mechanism for each of the

cylinders

46A and 46B, 47A and 47B operate in response to the ow of fluid passing through the ducts 157 and 158. In order for this feature to be accomplished, the diameterof the reciprocatory plugs 159 and 160 dissans posed in cavities 154 and 155 must be suiciently less than the diameter of the respective cavities so as to slide easily between the rst and second lengths of each of these cavities. In FIG. 3 the position of the plugs 159 and 160 corresponds to the positions they obtain during inlet of the uid to the pump cylinder 46A.

It is assumed that the piston 56A is moving downwardly of the closed end of cylinder 46A; this corresponds to a or pumping stroke. The initial compression stroke of piston 56A generates an increased pressure in cylinder 46A. a reduced pressure is manifested in the cylinder 46A. This reduced pressure is reilected in the second or lefthand lengths of the cavities 154 and 155. In response to this reduced pressure, the plugs 159 and 160 move to their left-hand positions illustrated in FIG. 3 whereby the

auxiliary passageways

161 and 162 are closed by the plugs 159 and 160, respectively. The chamfered ends of the plugs 159 and 160, and the orientation of the

auxiliary passageways

161 and 162 relative to cavities 154 and 155, assures that plugs 159 and 160 move to the extreme left or inner ends of their respective cavities. As the plug 159 moves to the left end of cavity 154, the inlet duct 157 is exposed tothe cylinder duct 153 across the rst or right-hand length of cavity 154 so that the fluid to be pumped is introduced into cylinder 46A. At the same time that plug 159 moves to the left-hand portion or second length of cavity 154, plug 160 assumes the same relative position in cavity by virtue lof the reduced pressure manifested in the left-hand end of cavity 155 through the auxiliary passages 162. In this position plug closes the cylinder duct 153 from communication with cavity 155 and, accordingly, from communication with the outlet duct 158.

Next, let it be assumed that the piston 56A reaches the lower point of its reciprocatory motion in cylinder 46A and begins to move upwardly during a compression or pumping stroke. The initial compression stroke of piston 56A generates an increased pressure in cylinder 46A. This pressure is reflected in the left-hand portions or second lengths of the cavities 154 and 155. This is possible because of the chamfered ends of plugs 159 and 160 and because of the orientation of the

passages

161 and 162. The manifestation of the increased pressure in cylinder 46A through the passage 162 at the chamfered end of plug 160 induces plug 160 to move into the first length or right-hand portion of cavity 155. As this motion occurs, the cylinder duct 153 is exposed to cavity 155 and to the outlet duct 158. As this communication is accomplished, fluid pumped in cylinder 46A is discharged through the -outlet duct 158. As the pumped Huid begins to flow through duct 158 a'venturi eect is manifested with respect to the angled auxiliary passageway 163. In other words, a reduced pressure is manifested in duct 163 according to the venturi principle of Huid flow mechanics. This reduced pressure in duct 163 is in turn manifested at the right end or first length of the cavity 155 further inducing plug 160 to 'continue its reciprocatory motion to a position adjacent the lixed plug 147. Simultaneously with such motion of plug 160, plug 161 is induced to move to the first length or right-hand portion of cavity 154 by virtue of the increased pressure manifested at the left end of cavity 154 through passageways 161. Such motion of plug 159 closes cylinder duct 153 from communication with the inlet passage 157. If there were no motion of the plug 159, the discharge from cylinder 46A during a compression stroke would be outwardly from the housing 35 through the inlet duct 157.

The dynamically operated valving mechanism for the

compressor cylinders

46A, 46B, 47A and 47B provides a compact and effective means for regulating the ilow of the fluid pumped by the pistons in the respective cylinders. Such a valving mechanism does not require any mechanical linkages to the moving parts of the iiuid pump or to any auxiliary timing mechanism. In a preferred form of the invention the reciprocating plugs 159 and 160 are 1 3 fabricated of Teon Such a material has an extremely `low coefficient of friction such that fine tolerances are permitted between the plugs and the limits of the cavities in which they reciprocate, and also such a material is resistant to corrosive action by the material being pumped in the respective cylinders.

Since the valves for the inlet and outlet of each compressor cylinder are operated by the uid pumped rather than by moving mechanical links, there is no mechanical loss from the friction associated with such sliding parts. The compressor 30, and the entire modular power unit 17, is thus a more efficient and longer lasting apparatus than if mechanical valves were provided. Also, the selfcontained nature of the valve apparatus described as- Sures that the anhydrous ammonia compressed in

cylinders

46A, 46B, 47A and 47B will not leak from the com pressor. This is an important feature when the circulating medium is toxic, has `an overwhelming odor, or is flammable.

As mentioned above, the valving mechanism for the remaining cylinders 46B, 47A and 47B of the two stage compressor 30 of the refrigeration apparatus illustrated in FIG. 1 is similar to that described in conjunction with cylinder 46A. Cylinder 47A has a pumped fluid inlet duct 164 and a pumped fluid outlet duct 165. The ow of the fluid in the inlet and outlet ducts associatedwith the first stage compressorcylinder 46A is from the front surface 52 to the rear surface 53 of the housing 35; the flow through the ducts 164 and 165 of cylinder 47A is in the reverse order.y Accordingly, multi-staging of the cylinders 46A and 47A is accomplished by connecting a duct or tubing 1'66 between the outlet duct 158 of cylinder 46A to the inlet duct 164 of cylinder 47A (see FIG. 2).

Since the pistons in cylinders 46A and 47A move in phase with one another, both cylinders 46A and 47A experience suction or compression strokes at the same time. However, the presence of the cylinders 46B and 47B provide for a pump or compressor apparatus wherein the suction or compression strokes are out of phase with the aforementioned cylinders. Such a configuration, i.e., a two-stage compressor wherein each stage has two cylinders with the pistons in each cylinderV being 180 out of phase with the other, provides for a compressor having a smooth discharge. The discharge from the compressor thus is more free from pulsations and vibrations associated with a single-stage compressor. Such a compressor is referred to as a double-acting compressor.

The ducting associated with the multi-stage compressor 31 of this invention is illustrated in part in FIG. 2. A suction manifold 167 is provided adjacent the sidewall 51 of housing 35 below the compressed gas manifold 135 associated with the prime mover cylinders 45A and 45B.

Branch ducts

168 and 169 extend from the inlet or suction manifold 167 to the inlet ducts 157 associated with the first

stage compressor cylinders

46A and 46B. Similarly, a discharge manifold 170 is provided adjacent the opposite sidewall 50of` housing 35 below the discharge manifold associated with prime mover cylinders 45A and 45B.

Branch ducts

171 and 172 extend from the discharge manifold 170 to the outlet ducts 165 of the second stage compressor cylinders 47A and 47B. In the preferred embodiment of the invention, represented by the schematic vdiagram of FIG. 1, the suction maniv fold 167 for compressor 30 is connected to duct 29 which extends from the outlet of the refrigerator evaporator 28. The discharge manifold 170 is connected to duct 33 which joins the discharge duct 24 from the discharge manifold 138 of the prime mover 17. Ducts 24 and 33, as mentioned above, combine into the upstream leg 14A of the common iiuid` flow leg 14 of the system illustrated in FIG. 1.

The manifold 166 connected between cylinders 46A and 47A serves as an accumulator for the discharge of the fiuid in cylinder 46A prior to introduction of the fluid into cylinder 47A since the pistons 56A and 57A are in phase. If it is desired that the first stage pump cylinders discharge directly to the second stage cylinders, then ducting is provided between the outlet of cylinder 46A and the inlet of cylinder 47B. Similar ducting is provided between the cylinders 46B and 47A. Such a ducting system, however, may be more voluminous than the system illustrated although the pressure head loss and the over-all eiciency of the compressor will be increased. The accumulator feature of duct 166 is useful only when the fluid pumped is a compressible fiuid; such is the case with the refrigeration system shown in FIG. 1.

While it is within the scope of this invention that the compressor 30 be mounted in a housing completely separate from the housing for the prime mover 17, the ganging together of the pistons 55-57 of the prime mover and the compressor provides an extremely compact modular power unit having utility in al self-contained portable refrigerating chest as provided by this invention.

The refrigeration system illustrated in FIG. 1 includes a pump 18 for that portion of Vthe fluid medium which circulates through the power loop 12. As illustrated, pump 18 is mechanically directly connected to the power unit 17. In a preferred form of the invention, the pump 18 is included within the housing of the power unit 17 in a manner similarv to the inclusion of the rst and second stage compressors 31 and 32 in the housing of the power unit 17.

Referring to FIG. 3, a pump cylinder is formed in the lower portion 37 of the power unit housing 35. The axis of the pump cylinder 175 is parallel to the direction of reciprocation of the gang beam 54 and, as illustrated, is concentric to the axis of the bore 92 wherein the rod 93 reciprocates. A pump piston 176 is disposed in cylinder 175 and is connected to the gang beam 54 by a connecting rod 177. A preferred form of the invention provides that the connecting rod 177 is an integral portion and extension of the reciprocating rod 93. A piston ring 178, in the form of an O-ring, is mounted peripherally of the piston 176 to provide sealing engagement with the vertical walls of 'the pump cylinder 175. A single pumped uid inlet and outlet duct 179 is provided through the housing portion 37 from the lower surface of the housing 35 into communicati-on with cylinder 175. The lowermost portion of the duct 179 is internally threaded to accommodate a pipe fitting whereby ducting externally of housing 35 may be connected into fluid flow relation with cylinder 175. Suitable check valve mechanisms 20 and 21 (not illustrated) are provided inthe ducting externally of housing 35 to facilitate the use of a single duct communicating with the cylinder 1.75,. It is Within the scope of this invention, however, that a pair of ducts for inlet` and outlet of pumped fluid to the pump chamber 175 may be provided, and that each of these ducts have a suitable check valve associated therewith.

A portable refrigerator chest 180 provided by this invention is illustrated in FIG. 9. Generally speaking, the refrigerated chest 80 comprises an upwardly open shell, a lid, and means connected to the shell for engaging the lid in closure relation with the shell. A partition is provided transversely of the shell to vdefine first and second portions of the shell. Insulation means are disposed in the first shell portion and define a cavity opening upwardly of the first shell portion. A liner member configured generally to the shape of the cavity is disposed in the cavity in spaced apart relation from the insulation; the liner member opens upwardly of the cavity. Liner mounting means are connected from the liner member to the shell and to the partition for mounting the liner in the cavity in spaced apart relation to the insulation. A refrigerant lfluid is provided in the cavity between the liner member and `the insulation. A coolant fluid circuarsenal lating means is disposed in the cavity between theinsulation and the liner member. Insulation is disposed in the lid so as to be in overlyingrelation to the shell first portion when the lid is in closure relation with the shell. Further, the chest includes means in the shell second portion for chilling coolant fluid and for circulating chilled coolant fluid through the coolant circulating means to freeze the refrigerant fluid.

The chest 180 includes a shell-like lower portion 181 and a lid 182. Preferably the lid is hinged to the lower portion 181 by hinge and latch means (not shown) which are well-known to those skilledY in the art of fabricating insulated containers. The shell 181 has end Walls 183 and 184, a bottom wall 185, and front and rear walls which are not illustrated. A partition 186 is provided parallel to the end walls 183 and 184 to divide the lower portion of the chest 180 into a first portion 187 and a second portion 188. As illustrated in FIG. 9, the first portion of the chest occupies -the major volume within the shell 181. Partition 186 extends between the forward and rear walls and between the bottom 185 and the upper limit of the lower shell 181.

A solid insulation material 190 lines theinterior Walls of the shell first portion 187. This insulation 190 has a thickness, relative to the boundaries of the first shell portion 187, of approximately 1% inches in a preferred embodiment of thisinvention. The insulation 190 defines a cavity opening upwardly :of the shell 181. A suitable insulation material is expanded polystyrene or polyurethane foam. Y

A liquid impervious membrane 191V covers theinterior surfaces tof the insulation 190 defining the upwardly open cavity. This membrane may be aluminumfoil or may be a sprayed plastic material which is allowed to harden on the surface of the insulation 190. f v

A liner orwell member 193, configured generally to the configuration Vof the cavity defined by insulation 190, is positioned Within the cavity and opens upwardly of the shell 181. -The dimensions of the liner 193 are less than the dimensions of the cavity as defined by the liquid impervious membrane 191. Accordingly, a space isprovided between the exterior sides of the liner 193 and the liquid impervious membrane 191. In a preferred form of the invention such a clearance is on the order of s/s inch. A peripheral ange 194 is provided around the upper exterior edge of the liner 193. Flange 194 is connected to the upper extent of the shell first portion 187 at the parting line 195 between the shell 181 and lid 182. An effective method of securing flange 194 to shell 181 is by welding. As illustrated in FIG. 9, the liquid impervious membrane 191 extends lalong the underside of flange r94 to theinner walls of shell 181 to provide for complete liquid sealing. of the insulation material 190.

A refrigerant fluid 197, such as a brine or the like, is disposed in the space between the liquid impervious membrane 191 and the liner member 193. Preferably, the uid provided in this chamber is not freezable and is stable in the range of operating temperatures (-l0 F.7to 100 F.) encountered in the device. `A coolant circulation coil 198 is disposed in the chest between liner 193 and the membrane 191. The coil 198 is in the form of a continuous length of tubing which is coiled into a basket-shape .to accommodate the liner member 193. The tubing 198 is in intimate contact with the refrigerant fluid 197. The coil 198 comprises the evaporator 28 illustrated in the schematic diagram of FIG. 1. Suitable inlet and outlet ducting (not shown) to and from the evaporator 28 is provided through the insulation .190 and through partition 186 into the second portion 188 of the chest 180 forconnection to the apparatus mounted in portion 188 and to be described below.

The lid 182 preferably is of aAdish-shaped configuration which is concave downwardly. A partition1919 is provided in lid 182 and extends between the front and rear walls of the klid in alignment with the shell partition 186.

The portion of the lid 182 overlying the shell first yportion 187 contains an insulation material 200, preferably of the type used in the shell first portion 187. An extruded .gasket retainer 201 is mounted to the inner extent of the lid around the' periphery of the first-portion and mounts a resilient gasket 202. The gasket 202 is engageable with the fiange 194 of the well or liner 193 when the lid 182 is in closure relation with the shell 181. In a preferred form of the invention, the insulation 200 in lid 182`is completely hermetically sealed by a plate 203 which is secured to theinner extent of the gasket molding 201. Preferably plate 203 is a piece of sheet aluminum and serves to assure that moisture does not enter into the lid insulation 200.

The second portion 188 of the chest shell 181 is uninsulated. A series of louvres or air circulation vents 205 are provided in the wall 184 of the chest adjacent the bottom 185. A similar set of louvres or air ventsr206 is provided in the upper portion of the lid 182 above the shell second portion 188. The modular power unit 17 described above is mounted in the lower portion of the shell second portion 188. The condenserV 23 is mounted above the modular power unit by a series of brackets 207 connected to the partition 186. p

As illustrated in FIG, 9, a fan 34 is mounted to the modular power unit 17 'adjacent the underside of lthe condenser 23 to provide a forced draft of ambient air upwardly past the tubes of condenser 23 through which the gaseous .phase of the circulating medium circulates for condensation therein.l The gaseous phase of the circulating medium is provided from the Ioutlets of the power unit power cylinders 45A and 45B and from the compressor 30.

Fan 34 is mounted to the modular power unit housing 35 in a manner illustrated in FIG. 3. It was mentioned above that the fly-wheel has a gear portion 102 about its lower periphery. Gear .102 engages a gear 218 which is secured to a fan shaft 211 journaled into a recess 212 in the upper portion of the housing 35. A journal bearing 213 is disposed in the recess or well 212 and engages the lower. end of the fan shaft 211. A radial collar 214 is provided on the shaft 211 and is positioned on shaft 211 such that the upper surface of collar 214 is substantially coplanar with the upper surface 48 of housing 35. An aperture 215 is formed through the top plate to accommodate the shaft 211. A thrust bearing 216 is provided in the underside of the top plate 110 peripherally of hole 215 and engages the upper surface of the shaft collar 214. The under surface of the collar 214 engages the upper end of the journal bearing 213. A fanrotor 217 is secured to the upper end of fanV shaft 211. Rotational motion of the ily-wheel 100 rotates the fan shaft 211 through interaction between the

gears

102 and 210.

Suitable ducting, such as pipe or tubing 219 connected to the inlet-outlet duct 179 of the liquid pump 18, is provided from the power unit housing 35 to the condenser 23.-

The inlet and outlet ducts to and from the evaporator coil 28 are connected to the condenserrand to the suction manifold of the compressor, respectively, according to the schematic illustration of FIG. 1. It is considered'that such auxiliary piping and ducting connections between the elements of the refrigerator chest describedabove are within the talents of one skilled in the manufacture of refrigeration systems and therefore such auxiliary ducting is not illustrated.

As mentioned above, the boiler for the anhydrous ammonia circulation medium is adapted for use in conjunction with a campfire or any other heat source such as gas, gasoline, or kerosene combustion unit. Such a feature provides a refrigerator chest 180 which is extremely useful on camping trips. FIGS. 7 and 8 illustrate a preferred embodiment of the boiler 15. The boiler 15 comprises a coiled length of metal tubing 220. The tubing has opposite ends 221 and 222 to which are attached pipe fittings 223 and 224.,l The end 221 of the tubing is the inlet end of the coil 220 while end 222 corresponds to the outlet of 1 7 the boiler. From the inlet, the tubing 220 is arranged into a series of U-shaped bend portions 226 wherein the straight legs 227 of the bend portions 226 extend parallel to one another over the length ofthe boiler 15. As illustrated in FIG. 7, there are nine convolutions or bend portions 226, the central three of which are arranged in a horizontal section 223 with the two outer groups of three return bends being arranged in angular depending sections 229 and 239 having planar configurations oriented at substantially 120 relative to the central portion 228 (see FIG. 8).

A yoke member 231 of electrical insulation material bridges the opposite ends 221 and 222 of the coil tube adjacent the

pipe fittings

223 and 224. A 115 volt, 60 cycle A C. line cord 232 is connected to the insulating block 231. A resistance wire filament 233 is disposed internally of the tubing 220 over its length. One conductor 234 of the line cord 232 is connected through the insulator 231 to one end of the electrical resistance filament 233 and the other line cord conductor 235 is connected to the opposite end .of the resistance filament tube 233.

In operation at a camp location, suitable ducting or tubing for connection of the liquid phase of the circulating medium is connected to the inlet pipe fitting 223. Preferably, such ducting is connected to the pump .18 in power unit housing 35. A similar ducting or tubing is connected to the pipe fitting 224 for vconduction of the high energy circulating medium gaseous phase from boiler 15 to the power unit 17. Preferably such ducting is permanently fixed to the boiler 15 with the ends of each of these ducts remote from boiler 15 being fitted with a quick disconnect tubing fitting (not shown) adaptable for connection to the pump 1S and to the inlet of the power unit 17, respectively. The ducting from the boiler 15 and the quick disconnect pipe iittings, preferably similar to the self-sealing quick disconnect fittings used in conjunction with compressed air systems, are not illustrated since the selection of such apparatus is considered to be within the scope of the talents of one skilled in the art.

The chest 130 is used at a remote location, or campsite,

by connection of the boiler 15 to the pump 18 and the power unit as mentioned above. The boi-ler 15 is placed in or `directly adjacent a campfire. As the uid medium contained within the boiler 15 is heated, it is boiled from the liquid phase to the gaseous phase. The gaseous phase emerges from the boiler -15 at an elevated temperature and pressure and is introduced to the inlet manifold 135 of the modular power unit 17. This high energy gas operates the power pistons 45A and 45B according to the method of operation described above. Reciprocation of the beam 54 rto which the pump piston i178 is ganged causes the liquid phase of the circulating medium to be circulated into the boiler 15. Energization of the power loop 12 of the refrigeration system also energizes the refrigeration loop by virtue of the common flow leg 14 existing between the power and refrigeration loops 12 and `13 and because of the mechanical interconnection between compressor and the power unit 17. As the power unit operates according to the procedure described above, the exhausted or spent portion of the gaseous phase passing through the cylinders A and 45B is `passed through the condenser 23 wherein it is changed Vfrom the gaseous ph-ase to the liquid phase. A portion of the condensate is passed through the evaporator coils 198 lininggthe foodstuff receiving well 193 in the firs-t portion 187 of the chest 180. Prior to introduction into the coils 1-98, however, the liquid phase is passed through an expansion valve or capillary tube wherein the pressure of the -liquid phase is materially reduced. In the coils 19S of the evaporator 28, the liquid phase of the anhydrous ammonia circulating medium is converted to its gaseous phase.Y The gaseous phase of the ammonia -coolant fluid is then passed from the tubing coil 198 into the inlet manifold 167 of compressor "31) for compression Iaccording to the "operation of the apparatus described above. As the liquid phase of the coolant fluid is evaporated or fiashed into t-he gaseous phase in the coils `198 of the evaporator 23, heat is extracted from the refrigerant uid -197 until the refrigerant cools to the desired temperature. After the refrigerant cools, the boiler 15 may be removed from the campfire to shut down the power unit. The cooled refrigerant fluid is their relied upon to `maintain the interior of Well 193 in a refrigerated -or cooled condition such that perishable foodstuffs may be kept for an extended period of time within the insulated well 193.

As illustrated in FIG. 9, the power unit 17 and condenser 23 are mounted in xed relation to the chest 180. It is within the scope of this invention, however, that the power unit 17 and condenser 23 may be contained in its own container separate from the insulated portion 187 of the chest 139. In such case the ducting from the evaporator 198 includes self-sealing quick disconnect connections adjacent the partition `136. Such separability of the power unit 17 and condenser 23 provides for flexibility of the apparatus according to the features described below. FIG. l0 is a schematic representation of the circulation of the anhydrous ammonia circulating fiiuid when the refrigerant loop is disconnected from the power loop as, for example, when the refrigeration process is not needed in order to maintain a low temperature in the food storage well 193.

If the power unit `17 and condenser 23 are removable from the food storage portion of the chest, auxiliary features of the invention may be used. It was mentioned in the introduction to this description that this invention contemplates the provision of electrical generator. This feature of the invention is illustrated in IFIG. 6.

The reciprocating rod 93 which extends upwardly through housing bore 92 lends itself to the provision of an alternating current electrical generator. A central portion of the reciprocatingrod 93 is comprised of a length of permanently magnetizfed metal 249 secured to the adjacent non-magnetic portions of the rod 93 by bolts or

stud portions

241 and 242 extending from the non-magnetic portion and engagcable with-in threaded recesses 243 and 244 provided in opposite ends of the magnet 24). An annular recess 245 is provided in the lower por-tion of the bore 92 l'adjacent cavity 42 in which the gang beam 54 reciprocates. A coil of electrical conductor wire 246 is disposed in the Iannular 4recess 245. Preferably, .as illustrated in KFIG. 6, the coil 246 is embedded in a body of electrical potting material 247. The coil 246 includes conductors (not shown) leading away from coil 246 for connection into an electrical circuit externally of housing `35.

AAs the rod 93 reciprocates in the bore 92, according to the process fdescribed above, the movement of the perma nent magnet 240 past the coil 246 generates a voltage in coil 246. Since the motion of the magnet 240 is a reciprocating motion, -t-he voltage generated in coil 246 is al1 alternating voltage. `In a preferred form ofthe invention, the length of the magnet 240 is at least equal to the axial length of coil 246 plus the distance rod 93 reciprocates. In such a situation, neither of the opposite ends of magnet 240 come within the ends of the coil 246. Such a feature assures that the maximum possible voltage obtainable will be generated as magnet v240 reciprocates relative to coil 246. The rotary shaft 211 associated with fan 34 may also be used to drive a rotary electrical generator if the reciprocating generator provided in conjunction with the reciprocating rod 93 is not included in the apparatus of this invention. Such a rotary generator is illustrated at 250 in FIG. l0.

The electrical generator illustrated in FIG. 6 is especially useful when the apparatus for powering the refrigerator is removable from chest 180. After the refrigerator cycle has been run to refrigerate and freeze the refrigerant fluid 197, the lapparatus may be disconnected from the food storage portion 1 87 for powering electric lights during the evening or for supplying electrical power to any appliance which is desired to be operated.

In initially loading the `food storage well 193 prior to I@ departure on a camping or picnic trip for example, the electrical heating element 233 included within boiler 1S is used since it is not normally the practice to lhave an open tire burning in a house, particularly in the summertime. The refrigerator provided by this invention may be operated indoors by plugging the line cord 232 into a suitable electrical outlet to heat the resistance filament 233. The heating effect is sutiicient -to change the circulating fluid medium within boiler from its liquid to its gaseous phase su-ch that the power unit 17 becomes operative. In this manner the refrigeration chest 180 may be operated indoors as well as outdoors in conjunction with a carnpre. When the power unit and condenser are located in a housing detachable from the food storage chest, the electrical operation of the refrigeration system is particularly convenient. If t-he food chest is to be used on a short picnic or the like, the refrigerant fluid 197 may be frozen by electrical loperation of boiler 15. The power unit 17 `and condenser 23 are then disconnected from the food chest and left at home. This means that only the Weight ofthe pre-cooled and loaded food chest need be carried to the picnic site.

The chest 180 of this invention provides =a .self-contained body of refrigerant fluid such as brine or the like. This is to be compared with the removable brine filled inserts which lare provided in devices presently known. The removable inserts must be removed from adjacent the food storage area of .the chest for prefreezing in order that the food storage area of the chest may be refrigerated. This invention, on the other hand, provides a device wherein a smaller volume of refrigerant material is required. The reduction of the volume of the liquid refrigerant reduces the weight of the resulting apparatus. Furthermore, it is preferred that the chest of this invention `as well as the power unit 17, be fabricated from aluminum or magnesium alloy metal .-in order that the overaall apparatus be as lightweight las possible.

FIGS. 11, 12 and 13 illustrate an alternate preferred embodiment of the valve associated with the power piston cylinders 45A and 45B. Since all of these preferred embodiments are identical, only that valve mechanism associated with the upper power piston cylinder 45A will be described in detail below.

An elongated cylindrical valve chamber 70 is provided in the upper portion of housing and has its axis perpendicular to the rear wall 53 of the housing. Inlet and outlet ducts 72 and 73 of the same configuration as described above communicate from the front Wall 52 of housing 35 to the valve chamber 71B substantially concentric to the axis of reciprocation of the piston within cylinder 45A. An elongated cylindrical valve plug 270 is rotatably disposed within the valve chamber 7). The valve '70 is of the barrel type and has a peripheral 0-ring 79 engaged in an annular recess to 271 adjacent its forward end. A second O-ring 272 is engaged between the forward end of barrel portion of the valve 270 and a retainer ring Si) is engaged in an annular recess in the wall of the valve chamber 7b adjacent the linkage recess 82. The linkage recess 82 is of the general conguration described above in conjunction with FIG. 4.

Instead of a single slot communication between the valve chamber 70 and the power piston chamber 45A as described in conjunction with FIG. 4, in FIGS. 11, 12 and 13 a pair of intake and exhaust slots are provided between cylinder 45A and the valve chamber 70. An inlet slot 273 and an outlet slot 274 are spaced apart from one another and are disposed parallel to the axis of rotation of the v-alve member 27). The slots 273 and 274 communicate between the upper end of the cylinder 45A and the valve chamber 7i).

As illustrated best in FIG. 13, an inlet valve passage 275 and an outlet valve passage 276 are formed in valve body 270. The inlet passage 27S is formed in the valve body 270 in such a manner that when it forms a connection between the inlet slot 273 and the inlet duct 72,

20 the outlet valve passage 276 forms no connection with either the outlet slot 274 or the exhaust duct 73. Similarly, the outlet valve passage 276 is so positioned in the valve member 270 that when it makes communication between slot 274 and exhaust duct 73, the inlet valve passage 275 makes no connection with either the slot 273 or the inlet duct 72. The inlet valve passage 275 has an inlet end 277 and an outlet end 278. Similarly, the out- -let valve passage 276 has an inlet end 279 and an outlet end 233. The inlet end 277 of the inlet valve passage 275 and the outlet end 280 ofthe outlet valve passage 276 are disposed substantially centrally of the valve member j 27 @i so as to communicate with the inlet and outlet ducts 72 and 73, respectively. The outlet end 278 of the inlet valve passage 275 and the inlet end 279 of the outlet valve passage 276 are spaced apart from one another longitudinally of the elongate extent of the valve body 271i at the central portion of the valve body 270. Also, the valve passage ends 277 and 280 are on the opposite side of the axis of rotation of the valve body 270 from the valveV passage ends 278 and 279 (see FIGS. 1l, l2 'and 13).

The valve mechanisms illustrated in FIGS. ll, l2 and 13 provide iner control over the inlet and exhaust functions than does the valve mechanism illustrated in FIGS. 3 and 4 since less angular displacement of shaft 83 is required to operate the valve. Y

From the foregoing description and explanation of this invention, it is seen that the system and apparatus of this invention provides a unique refrigeration device which is compact and versatile. It is noted, however, that the environment of the invention comprising a campers food storage chest has been selected by way of example and is not to be considered as limiting the scope of the invention.

While the invention has been described above in conjunction with specic apparatus, this has been by way of example and should not be considered limiting the scope of this invention.

What is claimed is:

A system for a refrigerating apparatus having power and refrigerating loops for flow of a single circulating medium having gaseous and liquid phases, each of the power and refrigerating loops having a circulating medium flow path common to the other loop, the system compr1smg (a) heat input means in the power loop for changing the circulating medium from the liquid phase to the gaseous phase and having a circulating medium inlet anda circulating medium outlet,

(b) a power unit in the power loop having a circulating medium inlet and an outlet and connected to the outlet of the power loop heat input means,

(c) a circulating medium pump means in the power loop discharging to the inlet of the power loop heat input means and operatively connected to the power unit,

(d) a heat exchanger for changing the circulating mediurn from the gaseous phase to the liquid phase having a circulating medium inlet connected in fluid ilow relation to the outlet of the power unit and a circulating medium outlet, the outlet of the heat exchanger being connected in luid flow relation to the pump means,

(e) circulating medium liquid phase expansion and evaporatormeans in the-refrigerating loop for changing the circulating medium from the liquid phase to the gaseous phase connected in fluid flow relation to the outlet of the heat exchanger, and

(f) a gaseous phase compressor means having an inlet and an outlet in the refrigerating loop and operatively connected to the power unit, the compressor means inlet being connected in fluid flow relation to the expansion and evaporator means, the compressor 21 means outlet being connected in fluid ow relation to the inlet of the heat exchanger, (g) the power unit comprising (l) housing defining a central elongate cavity therein,

(2) rst and second pairs of oppositely disposed bores in the housing extending from .the Cavity to closed ends spaced from the cavity,

(3) a beam member disposed longitudinally of the cavity,

(4) a plurality of pistons connected to the beam member, each of said pistons extending from the beam member into reciprocal engagement with `one of the bores of the rst and second pairs of bores,

(5) compressed gas inlet and outlet ducts to and from the housing adjacent each -of the ones of the first pair of bores,

said ducts communicating with Ithe bores of the first pair 'at the closed ends thereof,

the inlet ducts being connected to the outlet of the power loop heat input means,

(6) valving means in said compressed gas ducts for alternating the communication of said rst bores between the compressed gas inlet and outlet ducts, one of the rst bores communicating with its associated inlet duct when the other of the rst bores communicates with its associated outlet duct,

(7) rst fluid duct means communicating with the second pair of bores and connected to the outlet of the expansion and evaporator means, and (8) second fluid duct means communicating with the second pair of bores and connected to the 5 inlet of the heat exchanger,

whereby said alternating communication of the compressed gas inlet and outlet ducts with the bores of the rst pair reciprocates the beam member laterally of the cavity, and whereby the second pair of bores and the pistons therein comprise .the compressor means in the refrigerating loop.

References Cited bythe Examiner l UNITED STATES PATENTS 1,451,303 4/23 Mitchell 23 0-52 2,052,407 8/ 36 King 62-438 2,226,271 12/ 40 Vose 62-438 2,444,489 7/48 Baker 62-439 2 2,532,234 11/50 Kimble 62-457 2,570,693 /51 Koonz S10-15 2,844,301 7/5 8 Newton 23 0-53 2,909,902 10/ 5 9 Newton 62--238 2,986,907 6/61 Hoop 62-510 2,991,632 7/61 Rogers 62-498 3,006,167 10/61 Lorch 62--438 3,024,374 3/62 Stauder 310--15 ROBERT A. OLEARY, Primary Examiner.

EDWARD J. MICHAEL, Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE 0F CORRECTION Patent No. 3,196,631 July Z7, 1965 Kenneth D. Holland It is hereby certified that error appears in the above numbered patent requiring correction and that the sa'id Letters Patent should read as corrected below.

Column I, line 20, for "chest" read chests column 3,

llne 9, for "take" read taken

columns

5 and 6, TABLE l, last Column, line 4 thereof, for "762" read M 672 Column 5, line 69, after "O-rng" insert 62 column 9, line ll, for "l0" read 100 column l2, lines 9 and l0, strike out "or pumping stroke. The initial compression stroke of piston 56A generates an increased pressure in Cylinder 46A.", and insert instead suction stroke for the pump or Compressor.

As the plston 56A moves away from the Closed end of Cylinder 46A,

Slgned and sealed this 8th day of February 1966. (SEAL) Attest:

ERNEST W. SWIDER EDWARD I. BRENNER Attesting Officer Commissioner of Patents