US2328439A - Heat transfer apparatus - Google Patents

Heat transfer apparatus Download PDF

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Publication number
US2328439A
US2328439A US369033A US36903340A US2328439A US 2328439 A US2328439 A US 2328439A US 369033 A US369033 A US 369033A US 36903340 A US36903340 A US 36903340A US 2328439 A US2328439 A US 2328439A
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Prior art keywords
motor
valve
pump
cylinder
valves
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US369033A
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English (en)
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Esnault-Pelterie Robert
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B9/00—Compression machines, plants or systems, in which the refrigerant is air or other gas of low boiling point
    • F25B9/06—Compression machines, plants or systems, in which the refrigerant is air or other gas of low boiling point using expanders
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
    • F02B75/00—Other engines
    • F02B75/16—Engines characterised by number of cylinders, e.g. single-cylinder engines
    • F02B75/18—Multi-cylinder engines
    • F02B75/22—Multi-cylinder engines with cylinders in V, fan, or star arrangement
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B29/00—Combined heating and refrigeration systems, e.g. operating alternately or simultaneously
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B29/00—Combined heating and refrigeration systems, e.g. operating alternately or simultaneously
    • F25B29/003—Combined heating and refrigeration systems, e.g. operating alternately or simultaneously of the compression type system
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B49/00—Arrangement or mounting of control or safety devices
    • F25B49/02—Arrangement or mounting of control or safety devices for compression type machines, plants or systems
    • F25B49/022—Compressor control arrangements
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
    • F02B75/00—Other engines
    • F02B75/16—Engines characterised by number of cylinders, e.g. single-cylinder engines
    • F02B75/18—Multi-cylinder engines
    • F02B2075/1804—Number of cylinders
    • F02B2075/184—Number of cylinders ten
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2400/00—General features or devices for refrigeration machines, plants or systems, combined heating and refrigeration systems or heat-pump systems, i.e. not limited to a particular subgroup of F25B
    • F25B2400/07—Details of compressors or related parts
    • F25B2400/074—Details of compressors or related parts with multiple cylinders

Definitions

  • An electric motor is connected to the common crank, and furnishes power needed to make up for friction and heat losses.
  • Air at the low pressure prevailing in the circuit enters the crankcase, and thence passes through valves lo cated in the heads of the pistons working in the pump cylinders and is discharged by the pump cylinders into a high pressure part of the system. After passage through a heat interchanger the highly compressed air passes to the motor cylinders where its entrance and dischargeis governed by cam-actuated spring-loaded valves.
  • One of the features of the present invention is a change in the form and mode of operation of these valves in order greatly to reduce the frictional resistance thereof and in that and other ways to increase the efiiciencyof the apparatus; From the motor cylinders the expanded air passes through a second heat interchanger and thence to the common crankcase, being new at the low pressure prevailing in the system. Means are provided for supplying make-up air and for bleeding air from the circuit, as needed, and control of output is under thermostatic control.
  • the apparatus by manual operation of valves and a switch, is adapted to be reversed in the effect which it produces, i. e., either to heat or to cool the atmosphere of an enclosed space.
  • valves of the motor losses occur due to fluid friction, the non-instantaneous opening and closing of the valves, pneumatic losses due to sudden enlargements, contraction and bends, and solid friction losses due to the inertia of the parts and the use of continuously acting closing springs.
  • These losses may be substantially reduced according to a feature of the invention by providing valves of the kind having ports in relatively sliding surfaces and by opening and closing th'ese valves by the sole agency of positively acting means.
  • the va es are preferably operatd by annular cam having inner and outer cam surfaces giving positive operation of the valve both in the opening and in the closing direction.
  • annular cams rotating at the same speed as the crankshaft makes it practicable to obtain quicker opening and closing of the valves than with cams rotating at half the crankshaft speed as described in the parent specification, but the disadvantage is encountered that it is then impracticable to regulate the heating and cooling output by varying the valve timing by means of a planetary gear.
  • the regulation of the amount of heating or cooling produced is effected by varying the volume of the dead space of the pump cylinders. In effect, therefore, the regulation is produced by varying the difference between the high and the low pressure of the cycle, while the point of cut-off in the motor cylinders remains fixed.
  • the motor cylinders are provided with a valve allowing fluid to pass into the high pressure conduit in the case of excess pressure in the cylinder, and a valve allowing fluid to pass into the cylinder from the low pressure conduit in the event of the cylinder pressure falling below the low pressure of the cycle.
  • pistons comprising a crown. portion provided with suitable packing and a crosshead portion carrying the gudgeon pin and provided with rollers arranged to run on the cylinder walls and to transmit the lateral forces thereto. All points of articulation both in the piston-connecting-rod crankshaft system and in the valve mechanism are furthermore provided with needle, roller or ball bearings with the same end in view.
  • the radial arrangement of the pump and motor cylinders is particularly advantageous in an apparatus of this kind, and it was proposed to use either a six-cylinder or a ten-cylinder unit. Further investigation has shown that with an eight cylinder unit the resultant loading of the common connecting rod bearing, while being substantially lower than that of a six-cylinder unit, is about equal to that of a ten-cylinder unit, so that having regard to the greatly reduced number of moving parts, an eight-cylinder unit presents substantial advantages over all other arrangements.
  • Figure 1 is a section through two cylinders, of an eight-cylinder motor-pump unit
  • Figure 2 is a section along the line II-II in Figure 1;
  • Figure 3 is a section along the line III-III in Figure 1, it being noted that this line is below the valve lamina on the left-hand side of the cylinder axis and above it on the right-hand side;
  • Figure 6 is a view similar to Figure 3 showing a further modification of the valve arrangement
  • Figure '7 is a section along the line VIIVII in Figure 6;
  • Figure 8 shows in its upper and lower halves two modifications of the valve arrangement shown in Figure 6;
  • Figure 9 is an elevation of a motor cylinder head, with parts broken away to show the arrangement of the pressure-equalising valves
  • Figure 10 is a plan corresponding to Figure 9;
  • Figure 11 is a plan view of the motor-pump unit showing diagrammatically the means for varying the dead space of the pump cylinders;
  • FIG. 12 is a fragmentary View showing the valve operating mechanism
  • Figure 13 is a section along the line XIIIXIII in Figure 12;
  • Figure 14 is a pressure-volume diagram for the motor cylinder showing the effect of the pressure-equalizing valves.
  • Fig. 15 is a schematic diagram of the system of the invention herein.
  • the heat transfer apparatus in which my invention is useful may be of the type shown in the parent specification.
  • Figure 15 a schematic diagram of such an apparatus (omitting valve actuating mechanism and pipe connections to all but two of the cylinders) which in the present instance incorporates a motorpump unit of eight cylinders.
  • compressed gas from the pump cylinders I passes through pipe III to the high pressure part of the system containing one or more heat interchangers I I5, where it gives off heat, and then returns through pipe I12 to the motor cylinders 2 where it is expanded.
  • Expanded gas passes from the pump cylinders 2 through pipe I13 to the low pressure part of the system containing one or more heat interchangers H9, where it absorbs heat, and then returns through pipe I10 to the enclosed crankcase I56 of the motor-pump unit whence it is drawn through inlet-valve openings in the heads of the pump pistons, thus completing the circuit.
  • An electric motor I 36 connected to shaft 3 supplies power needed to make up for heat and friction losses.
  • the pipes I1I, I12 and I13 are shown for convenience in Fig. 15 as being connected to but one each of the pump and motor cylinders. As shown in the parent specification similar connection may be made with all of these cylinders by use of suitable headers. Also, by means of reversing valves, and the like, as shown in the parent specification, the system may be utilized either to heat or to cool the space in which a particular heat interchanger is located.
  • the eight-cylinder motor-pump unit of which one pump and one motor cylinder are shown in Figur 1 at I and 2 respectively, comprises a crankshaft 3 having a crank-pin 4 On which is suitable materials can also be used.
  • the pistons of the pump and motor cylinders are shown at 5 and l respectively and are similar in design in that they both comprise a crown portion .8 and a cross-head portion 9.
  • the crown I portion 8 carries piston rings 18, while the crosshead 9, to which the connectingrod l I is articulated by means of a needle bearing, carries two rollers I2 also by means of needle bearings.
  • the rollers I2 run on the cylinder walls and transmit thereto the lateral thrusts resultin from the obliquity of the connecting rod.
  • the gene-ratrix of the rolling surface of the rollers is an arc of smaller radius than that of the cylinder.
  • the crown portions 8 of the pump pistons 6 re provided with a number of inlet-valve openings I3 ( Figure 3) arranged regularly at a distance from the axis of the piston and having their inner margins crenellated so as to resemble the .outsp-read fingers of a hand.
  • a flexible 1am- .ina I4 overlies the openings It and is fixed against rotation by a central screw i5 and an eccentrically arranged pin Q6.
  • the lamina M has a plurality of openings It formed therein .so that the crenellated margins of the openings I3 are overlapped by the lamina to a substantially constant extent.
  • the lamina I4 is preferably composed of fibrous material bonded with a synthetic resin, but thin sheet metal or other In order to increase the flexibility of the marginal portions of the laminae, and thereby obtan a wider openthe valve laminae M are not rigidly clamped to the crown portions of the pistons '5.
  • the centre of each 1 is capable of sliding upon screw I 5 but is sea c upon the openings I 3 bythe resilient lamina I!- acting as a spring.
  • inlet-valve openings I3 have their outer margins crenellated so as to resemble the outsp-read fingers of a hand.
  • the flexible lamina M which overlies the openings l3 and is held in position by screw I 5 and pin I6 has its periphery crenellated in a manner corresponding to the openings it so that the crenellated margins of these latter are overlapped by the lamina to substantially constant extent.
  • Slits i? are provided to increase the flexibility of the marginal portions of the laminae.
  • Figure 8 shows an advantageous modification of Figures 6 and '7 in which the valve lamina 14 is made a little more flexible.
  • the lamina I4 is partly covered by a resilient lamina IB acting as a spring and assisting the seating of the valve proper.
  • the upper part of Figure 8 shows a star-shaped resilient lamina with points engaging alternate fingers of the valve lamina, while the lower part of the figure shows a construction in which the star has the same number of points as the valve lamina It has fingers.
  • a discharge valve I9 of sim ilar construction is carried by a shallow pist0nlike head 29 which is axially slidable in a block ,2I composed of a synthetic resin material incorporating friction-reducing, substances.
  • the block 2I constitutes a heat barrier between the pump cylinder l and the cylinder head 22 and is shaped at 23 to form a flexible lip engaging the sliding head 29 in the manner of a cupleather packing. Rotation of the sliding head is prevented by a screw 24 engaging a slot 25, while axial movement is provided for by means of a screw-threaded shaft 26 fixed to the sliding head and passing through a corresponding nut 2'! supported a thrust bearing 28 and eyed to a gearwheel 29.
  • the dead space of the pump cylinder is varied by the axial movement of the sliding head 28.
  • the gearwheel 29 of each pump cylinder is engaged by a gearwheel 30 mounted on a radial shaft 3!.
  • the radial shafts carry bevel pinions 32 meshing with a central bevel pinion 33, so that the turning of this latter varies equally the dead spaces of all the pump cylinders and therefore also th difference between the high and the low pressure of the cycle.
  • the heating or cooling output of the apparatus naturally varies in a corresponding manner.
  • the heating and cooling may be controlled by thermostatic means acting on a motor for turning the shaft of the bevel wheel 33.
  • motor cylinders 2 are provided with heads comprising a block and a top plate at bolted to a flange at the upper end of the cylinder.
  • the block 40 is also composed of a synthetic resin material incorporating friction-reducing substances and on each side of the cylinder head space 42 formed in it, it is provided with a passage 3, 44 extending laterally over substantially the whole width of the cylinder.
  • the passages M respectively are transversely arranged the inlet valve 45 and the exhaust valve 43, both being rotary valves having a transverse passage in the manner of an ordinary plug cock.
  • the exhaust valves are preferably arranged to close shortly before the end of the exhaust stroke so that a certain quantity of gas is enclosed and compressed to a pressure not exceeding the high pressure of the cycle.
  • pressure-equalising valves 69 are provided in the cylinder heads (see Figs. 9 and 19).
  • the valves 60 open outw rdly under excess pressure in the cylinder space and allow working fluid to pass along passages l leading to the high pressure supply conduits (32.
  • Similar pressure-equalising valves 53 are provided opening inwardly so that when the ratio of the high and low pressures (a and h respectively of Figure 14;) is reduced by increasing the dead space of the pump cylinders whereby the final pressure in the motor cylinders falls towards a value c which is lower than the low pressure 2) of the cycle, working fluid can enter the cylinders from the low pressure conduits 64 along the passages 55 before the exhaust valves 45 are operated. This maintains the final pressure (i in the motor cylinders as near the low pressure I) as is possible. Frictional forces resisting the operation of the valves are thus substantially reduced and unbalanced back pressures on the pistons avoided.
  • the pressureequalising valves may advantageously be constructed in the form of crenellated flap valves of the kind illustrated in Figures 3 to 8.
  • a. motor-pump unit which includes a. motor-pump unit, a source of added power therefor, and a non-condensing gas circuit having a high pressure part into which the pump discharges and from which the motor is fed and a low pressure part into which the motor discharges and from which the pump is supplied
  • the com. ination of means to vary the ratio of high to low pressure in the gas circuit by varying the dead space of a pump cylinder and a yieldaoly-held pressure-relief valve permitting gas to return from a low pressure part of the circuit to a motor cylinder when the pressure in the latter falls below said low pressure.
  • thermoelectric apparatus which includes a motor-pump unit, a source of added power therefor, and a non-condensing gas circuit having a high pressure part into which the pump discharges and from which the motor is fed and a low pressure part into which the motor discharges and from which the pump is supplied, the combination of means to vary the ratio of high to low pressure in the gas circuit by varying the dead space of a pump cylinder, a camactuated exhaust valve for a motor cylinder, and a spring-held Valve arranged to permit gas to return from a low-pressure part of said circuit to said motor cylinder while the exhaust valve thereof is closed when the pressure in said cylinder falls below the pressure in said part of said gas circuit.
  • thermoelectric heat transfer apparatus which includes a motor-pump unit, a, source of added power therefor, and a non-condensing gas circuit having a high pressure part into which the pump discharges and from which the motor a low pressure part into which the m charges and from which the pump is Sl lied, the combination of means to vary the ratio of 7.
  • heat transfer apparatus which includes a motor-pump unit, a source of added power therefor, and a non-condensing gas circuit having a high pressure part into which the pump discharges and from which the motor is fed and a low pressure part into which the motor discharges and from which the pump is supplied, the combination of a movable valve for controlling the flow of gas between a motor cylinder and a part of said gas circuit, said valve being capable of closing without meeting a positive abutment, cam surfaces and paired cam-followers operating together to actuate and control the movement of said valve at every position in its path of travel, and a spring-held valve arranged in shunt with said cam-actuated valve to permit backward flow of gas when negative pressure develops at the cam-actuated valve while the latter is closed.
  • a valve for controlling the flow of gas between a motor cylinder and a part of said gas circuit said valve being capable at that end of its path of travel corresponding to closed position of further movement beyond the position at which the flow of gas is shut off, and means to actuate and'control the movement of said valve at every position in its path of travel, said means consisting of inner and outer cam surfaces, paired cam-followers coacting therewith and connections thereof with the valve, whereby the valve is moved to permit and to shut ofi gas flow free of yieldable restraint opposing said movement in either direction.
  • a rotary valve for controlling flow of gas between a motor cylinder and a part of a closed gas circuit, said valve being capable at that end of its path of travel corresponding to closed position of rotating further beyond the position at which the flow of gas is shut off, and means to actuate and control the movement of said valve at every position in its arc of rotation, said means consisting of inner and outer cam surfaces, paired cam-followers coacting therewith and connections thereof with the valve, whereby the valve is rotated to permit and to shut oif gas flow free of yieldable restraint opposing said rotation in either direction.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Reciprocating Pumps (AREA)
US369033A 1939-12-21 1940-12-07 Heat transfer apparatus Expired - Lifetime US2328439A (en)

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Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2678155A (en) * 1948-05-25 1954-05-11 Durmorstan Company Inc Compressor-expander
US2724248A (en) * 1952-02-08 1955-11-22 Nat Res Dev Hot air engines and refrigerating machines
US3141309A (en) * 1962-07-10 1964-07-21 Carlos I Gesell Air conditioning apparatus
US4170166A (en) * 1977-05-31 1979-10-09 Reed John H Air motor with expansible chamber
US4326388A (en) * 1980-05-05 1982-04-27 Mcfee Richard Dual open cycle heat pump and engine
US4704949A (en) * 1983-07-15 1987-11-10 Robert Ogg Piston
US4714008A (en) * 1985-11-21 1987-12-22 Bowers Walter B Piston for internal combustion engines and the like
US4802382A (en) * 1986-06-26 1989-02-07 Societe Berthoud S.A. Connecting rod assemblies intended for the reciprocating driving of a piston inside a cylinder
US5462110A (en) * 1993-12-30 1995-10-31 Sarver; Donald L. Closed loop air-cycle heating and cooling system
US9234480B2 (en) 2012-07-04 2016-01-12 Kairama Inc. Isothermal machines, systems and methods
US20160097573A1 (en) * 2014-10-07 2016-04-07 General Electric Company Damper valve and a heat pump water heater appliance

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2678155A (en) * 1948-05-25 1954-05-11 Durmorstan Company Inc Compressor-expander
US2724248A (en) * 1952-02-08 1955-11-22 Nat Res Dev Hot air engines and refrigerating machines
US3141309A (en) * 1962-07-10 1964-07-21 Carlos I Gesell Air conditioning apparatus
US4170166A (en) * 1977-05-31 1979-10-09 Reed John H Air motor with expansible chamber
US4326388A (en) * 1980-05-05 1982-04-27 Mcfee Richard Dual open cycle heat pump and engine
US4704949A (en) * 1983-07-15 1987-11-10 Robert Ogg Piston
US4714008A (en) * 1985-11-21 1987-12-22 Bowers Walter B Piston for internal combustion engines and the like
US4802382A (en) * 1986-06-26 1989-02-07 Societe Berthoud S.A. Connecting rod assemblies intended for the reciprocating driving of a piston inside a cylinder
US5462110A (en) * 1993-12-30 1995-10-31 Sarver; Donald L. Closed loop air-cycle heating and cooling system
US9234480B2 (en) 2012-07-04 2016-01-12 Kairama Inc. Isothermal machines, systems and methods
US20160097573A1 (en) * 2014-10-07 2016-04-07 General Electric Company Damper valve and a heat pump water heater appliance
US9739392B2 (en) * 2014-10-07 2017-08-22 Haier Us Appliance Solutions, Inc. Damper valve and a heat pump water heater appliance

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Publication number Publication date
FR880162A (fr) 1943-03-16
CH223042A (fr) 1942-08-31

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