US3517523A - Air conditioner compressor and air fan speed controller - Google Patents
Air conditioner compressor and air fan speed controller Download PDFInfo
- Publication number
- US3517523A US3517523A US755177A US3517523DA US3517523A US 3517523 A US3517523 A US 3517523A US 755177 A US755177 A US 755177A US 3517523D A US3517523D A US 3517523DA US 3517523 A US3517523 A US 3517523A
- Authority
- US
- United States
- Prior art keywords
- motor
- air
- lever
- contactor
- temperature
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 239000003570 air Substances 0.000 description 29
- 230000007423 decrease Effects 0.000 description 12
- 239000003507 refrigerant Substances 0.000 description 9
- 239000003990 capacitor Substances 0.000 description 8
- 239000004065 semiconductor Substances 0.000 description 7
- 230000008859 change Effects 0.000 description 6
- 238000004804 winding Methods 0.000 description 6
- 230000001143 conditioned effect Effects 0.000 description 4
- 239000004020 conductor Substances 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 239000012530 fluid Substances 0.000 description 3
- 230000007246 mechanism Effects 0.000 description 3
- 230000009467 reduction Effects 0.000 description 3
- 230000002457 bidirectional effect Effects 0.000 description 2
- 230000003247 decreasing effect Effects 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 230000001105 regulatory effect Effects 0.000 description 2
- 238000009877 rendering Methods 0.000 description 2
- 229920001342 Bakelite® Polymers 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 239000012080 ambient air Substances 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 239000004637 bakelite Substances 0.000 description 1
- 230000004888 barrier function Effects 0.000 description 1
- 230000002146 bilateral effect Effects 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 230000001276 controlling effect Effects 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000011888 foil Substances 0.000 description 1
- 239000011810 insulating material Substances 0.000 description 1
- 230000004044 response Effects 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
- H02P25/00—Arrangements or methods for the control of AC motors characterised by the kind of AC motor or by structural details
- H02P25/02—Arrangements or methods for the control of AC motors characterised by the kind of AC motor or by structural details characterised by the kind of motor
- H02P25/04—Single phase motors, e.g. capacitor motors
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F11/00—Control or safety arrangements
- F24F11/30—Control or safety arrangements for purposes related to the operation of the system, e.g. for safety or monitoring
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F11/00—Control or safety arrangements
- F24F11/62—Control or safety arrangements characterised by the type of control or by internal processing, e.g. using fuzzy logic, adaptive control or estimation of values
- F24F11/63—Electronic processing
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F11/00—Control or safety arrangements
- F24F11/70—Control systems characterised by their outputs; Constructional details thereof
- F24F11/72—Control systems characterised by their outputs; Constructional details thereof for controlling the supply of treated air, e.g. its pressure
- F24F11/74—Control systems characterised by their outputs; Constructional details thereof for controlling the supply of treated air, e.g. its pressure for controlling air flow rate or air velocity
- F24F11/76—Control systems characterised by their outputs; Constructional details thereof for controlling the supply of treated air, e.g. its pressure for controlling air flow rate or air velocity by means responsive to temperature, e.g. bimetal springs
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F11/00—Control or safety arrangements
- F24F11/70—Control systems characterised by their outputs; Constructional details thereof
- F24F11/80—Control systems characterised by their outputs; Constructional details thereof for controlling the temperature of the supplied air
- F24F11/86—Control systems characterised by their outputs; Constructional details thereof for controlling the temperature of the supplied air by controlling compressors within refrigeration or heat pump circuits
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05D—SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
- G05D23/00—Control of temperature
- G05D23/19—Control of temperature characterised by the use of electric means
- G05D23/275—Control of temperature characterised by the use of electric means with sensing element expanding, contracting, or fusing in response to changes of temperature
- G05D23/27535—Details of the sensing element
- G05D23/27537—Details of the sensing element using expansible fluid
Definitions
- thermostatic controller providing coordinated onoff control of a refrigerant compressor motor, and onoff and temperature variable speed control of an air circulating fan motor.
- thermostatic controller provides normal snap-action, on-ofi, switch operation at adjustable high and low temperatures.
- Movement of a lever in accordance with temperature change in the snap-action mechanism is adapted to additionally change the value of resistance in the gate control circuit of a bilateral thyristor in accordance with temperature decrease to slow down a fan motor.
- Such lever additionally affords opening of a second switch to deenergize the fan motor when a low temperature limit is reached.
- a modified form of the controller permits selection of either the aforementioned temperature variable speed control of a fan motor, or manual adjustment of the fan speed.
- controllers are sometimes complex, and are difiicult to coordinate or synchronize with the thermostatic on-oif control of the refrigerant compressors.
- existing controllers utilize separate thermal sensing elements for the refrigerant compressor on-oft control, and for the fan speed control. This makes for difficulty in synchronizing the tracking of the two sensing elements so that there will be fixed coordination between the on-off temperature points for the compressor and the temperature range of speed variation for the fan motor.
- Some controllers utilizing a single sensing element employ photoelectric systems which provide variation in intensity of a light as a means of generating variable input signals for effecting speed variation of the fan motor.
- Another object is to provide a semiconductor fan speed control circuit wherein an adjusting element of a gating control impedance element is mechanically adjusted in accordance with change in position of the thermally responsive power element.
- a still further object is to provide a controller of the aforementioned kind wherein the temperature range over which fan speed control is provided, is adjustable within the limits of on-off operation of the compressor motor switch.
- a further object is to provide a modified form of controller, in which automatic temperature variation of fan speed control, or manual variation of the fan speed can be selected as desired.
- FIG. 1 is a schematic view of an air conditioner which embodies the improved controller
- FIG. 2 is a diagram of a variable speed control circuit used in the improved controller
- FIG. 3 is a view in side elevation of an improved controller constructed in accordance with the invention.
- FIG. 4 is a fragmentary view to larger scale showing certain of the details of the controller
- FIG. 5 is a view like FIG. 4, but showing the controller in a different operation condition
- FIG. 6 is a graph showing the relation between temperature and fan motor speed afforded by operation of the controller
- FIG. 7 is a schematic view of the controller when connected in a modified way with a fan motor.
- FIG. 8 is a schematic view of a modified form of controller affording either automatic or manual adjustment of the speed of a fan motor.
- FIG. 1 shows an air conditioner 10, which comprises a refrigerant compressor 12 driven by an electric motor 13, an evaporator or heat exchanger 14, condenser 16, an air circulating fan motor 18, and an electric controller 20 for coordinating starting and stopping of motors 13 and 18, and for varying the speed of the fan motor 18 in accordance with the change in air temperature on the air intake side of the evaporator 14.
- a refrigerant compressor 12 driven by an electric motor 13, an evaporator or heat exchanger 14, condenser 16, an air circulating fan motor 18, and an electric controller 20 for coordinating starting and stopping of motors 13 and 18, and for varying the speed of the fan motor 18 in accordance with the change in air temperature on the air intake side of the evaporator 14.
- Controller 20 is provided with a temperature responsive element 22 of the thermal fluid filled type which has its end portion 22a positioned in close proximity to the air intake side of evaporator 14.
- controller 20 comprises an electric switch 24, a diaphragm type power unit 26, a snap-acting switch operating unit 28 and a fan speed regulating circuit 30, mounted on a printed circuit board 32.
- Switch 24, diaphragm power unit 26, snap-acting operating unit 28 and temperature responsive element 22 comprise a known form of thermostatic switch unit 34 which is like that disclosed in the Kuhn Pat. No. 2,511,640.
- Switch unit 34 has an upper mounting bracket 36 which supports switch 24 and operating unit 28.
- a channel-shaped bracket 38 with outwardly extending arms is secured along its bight to the upper surface of bracket 36.
- a shallow channel-shaped bracket 40 is secured by ma chine screws 42 to the arms 38a of bracket 38.
- a shaft extension 44 extends thereof a suitable clearance opening (not shown) in the bight of bracket 40 and is secured by a set screw 44a to the shaft of a loading spring adjusting screw 46 of switch unit 28.
- Printed circuit board 32 is secured to an upstanding arm 40a of bracket 40 by machine screws 48.
- diaphragm power unit 26 comprises a cup-shaped diaphragm member 50 welded in a sealed relation to the outer cup-shaped case. 52.
- the movable wall 50a of diaphragm 50 is of a corrugated form, and a cupshaped loading spring follower or stirrup member 54 seats on its bottom surface against the bottom wall of diaphragm 50.
- a helically coiled loading spring 56 is disposed about on upwardly turned annular flange portion 54a of stirrup 54 and seats against the inside of the bottom wall of the latter.
- a nut 58 secured against rotation seats against the upper end of loading spring 56,
- Snap-acting switch operating unit 28 comprises two toggle levers 60 and 62.
- the levers 60 and 62 are both of generally hollow rectangular form, and are pivoted on opposite parallel side walls of a frame 66 by oppositely extending tabs (not shown) which engage with V-shaped notches formed in the frame side walls.
- a pair of parallel spaced apart tension springs 68 are anchored at corresponding ends in openings formed on the lefthand portion of lever 60 and the other ends of the springs are anchored in openings formed in the right-hand end portion of lever 62.
- the bearing notches are so positioned that the levers 60 and 62 have single stable toggle positions, namely, that shown in FIG. 3, to which they tend to return.
- lever 62 in stable position is defined by its engagement with the lower side of the head of an adjustable screw stop 69.
- the right-hand end portion of lever 62 depends downwardly at an angle and engages operating lever 70 of switch 24.
- the corresponding stable position for lever 60 is defined by the engagement of its left-hand end portion with inwardly turned tangs 66a of frame 66.
- Stirrup 54 has vertically extending portions 54b formed on opposite sides of the cup portion 54a and elongated notches 540 are formed in the portions 54b. Tabs 60a extending outwardly from the parallel sides of lever 60 extend into the notches 54c and engage at the upper closed ends of the latter with the portions 541). On decrease in temperature the pressure in diaphragm chamber 50x will correspondingly decrease. Loading spring 56 with following action moves stirrup 54 downwardly and the engagement of the portion 54b of the latter with the tabs 60a of lever 60 causes the latter to pivot counterclockwise (as viewed in FIGS. 3, 4 and in its bearing notches.
- a compound lever 72 is welded adjacent one end of the short side of its right angle member 74 to the left-hand end of lever 60.
- a flat spring member 76 is riveted adjacent one end to the longer side of member 74. Adjacent its other end spring 76 is riveted to a portion 78a of an operating member 78 which is preferably formed of molded insulating material.
- An adjusting screw 79 penegageable with a pivoted contactor 80, and projection 78d of member 78, and takes into a threaded boss formed adjacent the left end of the portion 74b of member 74.
- a substantially flat barrier portion 78b is integrally formed with portion 78a, and a cam projection 78c extends outwardly from one side of portion 78b and a second cam projection 78d extends downwardly.
- the projection 780 is engageable with a pivoted contractor 80, and projection 78d is engageable with the contactor 82 of an on-off switch 82.
- FIG. 2 shows a circuit diagram of the motor speed regulating circuit 30, which is mounted on printed circuit board 32, together with a motor 18 which in the preferred form shown is of the permanent split capacitor or shaded pole type.
- the circuit board 32 is provided with terminals A, M, B, C, L and D.
- Terminal A is connected to the upper terminal of a capacitor C1, and to the upper, main conducting terminal of a semiconductor bidirectional triode th ristor 86.
- the lower main conducting terminal of thyristor 86 is connected to terminal M and to one end of a resistor 88 which is connected in series with capacitor C1 and to the other terminal capacitor C2.
- Terminals B and C are connected together in series with a resistor 90, and in series with a semiconductor bidirectional diode thyrintor 92 to the gate terminal of thyristor 86. Also terminals B and C are connected in series with an adjustable resistor 94 to terminal D and to the upper main conducting terminal of thyristor 86. One end of a resistor 96 is connected to the point intermediate terminals B and C and resistor 94. The aforementioned contactor engages the resistance element of resistor 96. Terminal D has connection with contactor 80, and is connected to resistor 94, the upper main conducting terminal of thyristor 86 and the upper terminal of capacitor C1. Single pole switch 82 is electrically connected between terminals D and L.
- motor 18 has main winding 18a connected at one end to terminal M. At its other end it is connected to line L1 of a single phase A.C. voltage source in series with auxiliary winding 18b and a capacitor C3 to terminal M. Terminal L is connected to the other line L2 of the A.C. source.
- terminals A, B, C and D of circuit board 32 do not have any external connections. However, as will hereinafter be explained in connection with FIGS. 7 and 8, these latter terminals permit another possible motor connection and for a modified form of manual-automatic control.
- motor 18 will increase in speed as more and more resistance of resistor 96 is effectively removed from the circuit of the control gate of thyristor 86. It will be appreciated that counter-clockwise pivotal movement of contactor 80 will result in the increase of the amount of resistance of resistor 96 included in the gate control circuit of thyristor 86, and motor 18 will correspondingly decrease in speed.
- FIG. 3 it shows in some detail a preferred physical arrangement of the components of the fan speed control circuit described in conjunction with FIG. 2 mounted on printed circuit board 32 with the conducting foil portions on the reverse side shown in dotted lines.
- the thyristors 86 and 92 are mounted together on a heat sink comprising an inverted channel member 98d formed of a suitable heat conducting metal.
- Resistor 96 is suitably mounted on a Bakelite strip 100 which has a metal conductor portion 100a.
- Contractor 80 is pivotally mounted at 80a on board 32 and may be assumed to be provided with a torsion spring (not shown) which biases contactor 80 for counterclockwise pivotal movement.
- Contactor 80 throughout its range of pivotal movement has continuous engagement with the lower surface of a fixed conductor strip 82b of a member 82 which also integrally comprises the switch contactor 82a.
- Member 82 is riveted to the board 32.
- Contactor 82a is provided with a contact 820 which is normally held in engagement with a stationary contact 102 secured to a right angle bracket 104 riveted to board 32.
- Member 82 is electrically connected to terminal D, and bracket 104 is electrically connected to terminal L.
- An insulated cylindrical stop 106 is eccentrically secured on board 32, and as will hereinafter be explained, limits the counterclockwise movement of contactor 80.
- a right angle bracket 108 riveted to board 32 provides a stop to limit the clockwise movement of contactor 80.
- levers 60 and 62 toggle over center in a snap-action manner.
- switch 24 will be opened by counterclockwise pivotal movement of lever 70 caused by clockwise snap-action pivotal movement of toggle lever 62.
- the toggle movement of lever 60 in the counterclockwise direction will result in some further movement of contactor 80 on resistor 96 to cause a corresponding sudden decrease in motor speed represented by the line T.
- contactor 80 engages stop 106 and motor speed remains constant as depicted by the horizontal line -U of FIG. 6.
- lever 60 continues to pivot counterclockwise, and with it, lever 78.
- lever 78 By the time point V is reached lever 78 has engaged its cam projection 78d against contactor 82a and moved the latter downwardly to disengage its contact 82c from contact 102. Thus motor 18 will then be deenergized to stop the circulation of air through evaporator 14 into the conditioned space.
- lever 78 results in its projection 78c being reengaged with contactor 80 to aiford corresponding clockwise pivotal movement of the latter.
- the clockwise pivotal movement of lever 80 on resistance 96 effects reduction of resistance in the control circuit of the gate of thyristor 86, and the latter then progressively conducts earlier in each half cycle of the A.C. voltage to increase the speed of the motor 18 in accordance with the line X in FIG. 6.
- levers 60 and 62 toggle with snap-action to these positions depicted in FIG. 3 wherein lever 70 causes switch 24 to reclose to again energize refrigerant compressor motor 13. Due to the snap-action movement of lever 60 contactor 80 moves olf resistance 96 onto portion 100a of strip 100, thereby causing a sudden further 6 increase in speed of motor 12 as represented by the line Z in FIG. 6.
- FIG. 7 shows a slightly different hookup of the controller with a permanent split capacitor motor 110.
- phase windings 110a and 110b are connected at corresponding ends to supply line L1 of an A.C. supply.
- the other end of winding 110a is connected to terminal M on circuit board 32 and the other end of winding 11% is connected in series with a capacitor C4 to terminal D.
- motor 110 current will only be varied in winding 110a. This results in a lower harmonic content in the motor current, and consequent reduction in mechanical vibration noise.
- FIG. 8 shows a modified form of the controller adapted for selective automatic or manual control of the speed of air circulating from motor 18.
- the circuit board interconnections between terminals B and C are removed, and terminals B and C are connected to a contactor 112, and to a stationary contact 114 of a combination selector switch-manual speed control unit 116.
- Contactor 112 together with contact 114, and a second stationary contact 118 provide a twoposition selector switch.
- Contact 118 is electrically connected to the slider 120a of a variable resistor which has the right-hand end of its resistance element 120b electrically connected to terminal A on circuit board 32.
- control circuit means in circuit with said fan motor and connectable to a source of A.C. supply voltage comprising a semiconductor device having main conducting terminals connectable to said supply voltage and the fan motor, and having a control gate;
- controller in accordaance with claim 1, together with a second switch operable by said means affording movement of said mechanical adjusting element to interrupt power connected to said control circuit and the fan motor when the temperature to which said power element is subjected approaches a predetermined limit.
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- Signal Processing (AREA)
- Thermal Sciences (AREA)
- Fluid Mechanics (AREA)
- Fuzzy Systems (AREA)
- Mathematical Physics (AREA)
- Power Engineering (AREA)
- General Physics & Mathematics (AREA)
- Automation & Control Theory (AREA)
- Control Of Direct Current Motors (AREA)
- Thermally Actuated Switches (AREA)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US75517768A | 1968-08-26 | 1968-08-26 |
Publications (1)
Publication Number | Publication Date |
---|---|
US3517523A true US3517523A (en) | 1970-06-30 |
Family
ID=25038041
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US755177A Expired - Lifetime US3517523A (en) | 1968-08-26 | 1968-08-26 | Air conditioner compressor and air fan speed controller |
Country Status (2)
Country | Link |
---|---|
US (1) | US3517523A (enrdf_load_stackoverflow) |
GB (1) | GB1232200A (enrdf_load_stackoverflow) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3877243A (en) * | 1973-09-27 | 1975-04-15 | Daniel E Kramer | Refrigeration systems including evaporator with 2 speed fan motor |
US3938348A (en) * | 1974-10-15 | 1976-02-17 | Rickert Glenn E | Ventilating and/or cooling dehumidifier |
US4407446A (en) * | 1980-11-04 | 1983-10-04 | Nissan Motor Co., Ltd. | Control for automobile air conditioning system |
US5488835A (en) * | 1993-07-28 | 1996-02-06 | Howenstine; Mervin W. | Methods and devices for energy conservation in refrigerated chambers |
CN115614822A (zh) * | 2022-11-07 | 2023-01-17 | 珠海格力电器股份有限公司 | 风机盘管、送风构件及具有其的空调器 |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3385077A (en) * | 1967-02-23 | 1968-05-28 | Philco Ford Corp | Air conditioner |
US3390539A (en) * | 1966-10-31 | 1968-07-02 | Trane Co | Apparatus for controlling refrigeration systems |
US3398889A (en) * | 1966-01-24 | 1968-08-27 | Borg Warner | Control system for air conditioners and the like |
US3410105A (en) * | 1967-02-15 | 1968-11-12 | Philco Ford Corp | Air conditioner |
-
1968
- 1968-08-26 US US755177A patent/US3517523A/en not_active Expired - Lifetime
-
1969
- 1969-08-26 GB GB1232200D patent/GB1232200A/en not_active Expired
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3398889A (en) * | 1966-01-24 | 1968-08-27 | Borg Warner | Control system for air conditioners and the like |
US3390539A (en) * | 1966-10-31 | 1968-07-02 | Trane Co | Apparatus for controlling refrigeration systems |
US3410105A (en) * | 1967-02-15 | 1968-11-12 | Philco Ford Corp | Air conditioner |
US3385077A (en) * | 1967-02-23 | 1968-05-28 | Philco Ford Corp | Air conditioner |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3877243A (en) * | 1973-09-27 | 1975-04-15 | Daniel E Kramer | Refrigeration systems including evaporator with 2 speed fan motor |
US3938348A (en) * | 1974-10-15 | 1976-02-17 | Rickert Glenn E | Ventilating and/or cooling dehumidifier |
US4407446A (en) * | 1980-11-04 | 1983-10-04 | Nissan Motor Co., Ltd. | Control for automobile air conditioning system |
US5488835A (en) * | 1993-07-28 | 1996-02-06 | Howenstine; Mervin W. | Methods and devices for energy conservation in refrigerated chambers |
CN115614822A (zh) * | 2022-11-07 | 2023-01-17 | 珠海格力电器股份有限公司 | 风机盘管、送风构件及具有其的空调器 |
Also Published As
Publication number | Publication date |
---|---|
GB1232200A (enrdf_load_stackoverflow) | 1971-05-19 |
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