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S. 1 1 1 0 1 c 9».- - . v ‘N I O 1 OBILES. ~— .. . £11.. 2111.11 Am M CONTROL SYSTEMS m M 9 2.1.9.1.. .” 9. . AUTO MIGHTiGAN STATE RANDY 91.99na-~u.‘9- «990911-9999od~9oos -“.l-‘--"— -....09‘ O ’4 1 , . ‘ o ' 9 0.- O y 1 . 1 I . I) ~ ‘IGN ANALYSIS -OF AUTO .....fi...%..............._..1.....1... 1...... .... ..........,...S.... .....2...:............ ......§+.ax +1.3-.. . 01,1... 1 ‘V ‘ V 1 .91. .91 ‘1 1191_ .1.-Vol. . .s.*011111)<9¥§ 1 . 9.11 1..—11 . .1 91 . . O. (I 01 .. . .o. .11. ...11...l m1.J9...11r :‘t: .1... V91..91I1.J§119f S 9'1” . . .I‘l .. y. Ilv I). X 119.. . I .1... O o 1..“...1'...’ v...‘".‘ *1! ‘1.n..fi‘omhhfivt.“1.‘1hl¢‘H-lu.~mo and“ '1‘ 511.1"..Wovu910 THESIS L131? Micifigm State K. University W— ABSTRACT DESIGN ANALYSIS OF AUTOMATIC ENVIRONMENTAL CONTROL SYSTEMS - IN GENERAL MOTORS AUTOMOBILES By Randy J. Wheeler In recent years, the proportion of new cars built in the United States with factory-installed air conditioning systems has risen to greater than 40 percent. In addition, automatic control air condi- tioning systems are being built in increasing numbers. It is the purpose of this work to compare the three completely different systems now built in General Motors automobiles on the basis of production and service characteristics to aid Oldsmobile Division in setting future deSign goals. This thesis is one of the final stages in a five year work-study cooperative program involving four years study at General Motors Institute and one year of graduate study at Michigan State University. There are three different automatic air conditioning systems:' the Oldsmobile Comfortron,_the Buick Automatic Climate Control, and the Pontiac Automatic Temperature Control. The Comfortron is an electrical-vacuum system using electrical sensing and modulated vacuum control. The Automatic Climate Control is a mechanical- vacuum system using bi-metal sensing elements and vacuum control. The Automatic Temperature Control is an electrical-mechanical system using electrical sensing elements and electric motor control. The thesis draws conclusions and makes recommendations pertinent to future developments at Oldsmobile. DESIGN ANALYSIS OF AUTOMATIC ENVIRONMENTAL CONTROL SYSTEMS IN GENERAL MOTORS AUTOMOBILES ' By Randy, J . Wheeler A THESIS Submitted to Michigan State University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE ‘~— 0 Department of Mechanical Engineering I 969 ACKNOMEDGEMENTS ._ It is my sincere pleasure to thank the following individuals and organizations for their help in preparing this thesis. I wish to thank Mr. K. E. Maleitzke. Senior ProjeCt Engineer. Product Engineering, Oldsmobile, for the many patient hours and generous encouragement he gave. I would also like to thank the Service Departments of Oldsmobile, Buick. and Pontiac Divisions of General Motors Corporation for their permission to use pictures from their service manuals as illustrations for this thesis. I also wish to express my gratitude to all the individuals in many divisions of General Motors for their assistance in preparing this report. ii CHAPTER II III IV VI TABLE OF CONTENTS List of Tables List of Illustrations Introduction Oldsmobile Comfortron Buick Automatic Climate Control Pontiac Automatic Temperature Control Production Installation Adaptability Serviceability Conclusions and Recommendations iii PAGE iv 33 49 61 66 70 TABLE LIST OF TABLES Air Conditioning Factory Installation Figures Sensor Resistance vs Temperature Total Standard Burden Allowance Per System Number of Components and Connections Per System iv PAGE -I7 63 64 INTRODUCTION Air conditioning systems were firSt installed in automobiles in the years befbre World War 11. At first these installations were made 'on an individual basis by garages. The first factory-installed air conditioning systems were in Packards. All of these early systens had the evaporator installed in the trunk. The 1954 Pontiac was the first General Mdtors automobile to have the complete system in the front of the car. The entire automotive industry went to that system in the years shortly following that time and the basic air-conditioning system has remained much the same since then, with only evolutionary changes. ‘ One important change came with the advent of the air-mnx system. All previous systems used a water valve control to modulate the heater temperature and they had a completely separate air conditioning system with separate duct work. The air-mix system integrated the heater and air conditioning systems and used the principle of mixing heated and cooled air in appropriate proportions to achieve the desired outlet temperature. The air is then directed by door valves to the appropriate ducts. This system has the fOllowing advantages: 1. More rapid tannerature changes. 2. More precise temperature control. 3. Ability to dehumidify heated air to prevent fogging (especially useful on cool, humid days). I 2 The 1964 Cadillac Comfort Control was the first fully automatic system. All previous systems had required driver control of tempera- ture,fan speed, and mode (heater or air conditioning). The Cadillac system was an electrical-vacuum control system which was progranmed to perform these functions. Its main design requirements were: 1. To maintain passenger compartment comfort under all climate and engine operating conditions. 2. To relieve the driver from adjusting controls thereby releasing his fu1l attention to the task of driving. 3. To achieve the desired comfort level as rapidly as possible. ' ' Since then, all three major automobile manufacturers have developed automatic systems. General Motors alone has had no less than four com- pletely different systems in production with others under development. Figures from the March 5, 1969, issue of "Automotive Industries" Magazine illustrate the growing role of air conditioning systems in the ; automotive industry: TABLE 1 AIR CONDITIONING FACTORY INSTALLATION FIGURES Model Year Ikfllé. % of TOtal ProdUCtion 1965 2,060,675 23.30 1966 2,522,193 29.30 1967 2,905,750 38.40 1968 3,519,373 43.26 These figures indicate almost double the installation rate by percent of only four years ago. This is an impressive growth record fOr an option which is second to none in price except some engine options. The option prices range from $324 on an American Motors Rambler to $516 on a Cadillac. With increased demand fbr air conditioning systems, customer interest is also likely to go toward the more saphisticated automatic systems. Herein lies the motivation fbr this research. The purpose of this report is to provide Oldsmobile with some guidelines for future automatic air conditioning systems. It makes some pertinent conclusions about the systems now produced in General Motors and some recommenda- tions for future systens. The scope of this thesis was originally to include the cost of each system. This was found to be impractical, however. Though it is to be admitted that the cost is of prime inportance from an executive stand- point, it must be said that in this instance cost is not likely to be a good basis of comparison.' Consider the following examples in support of this assertion. The Cadillac Comfort Control and the Oldsmobile Comfortron are virtually identical systems in theory of Operation. Consider the blower Speed programs of each system. The Cadillac system has three normal control lever positions, LO-AUTO-HI. The Oldsmobile system has two an! 15 7" CLIMATE comm VENT Off L0 AUJO F90 ICE FIGURE 1 COMFORTRON AND AUTOMATIC CLIMATE CONTROL PANELS positions, LO-HI, as shown in Figure 1 (Page 3). In any of these posi- tions, each system is in automatic temperature control. The Cadillac system runs in L0 at one low blower speed, in AUTO at one of fOur automatically selected blower speeds, and in H1 at one high blower speed. In contrast, the Oldsmobile system runs in L0 in a range of five automatically selected low blower Speeds and in H1 in another range of I five high blower speeds. This difference is the result of engineering judgment and executive decision. There are also other differences be- tween the systems, but this difference will serve to illustrate the point. Another example is a difference between the Pontiac Automatic Temperature Control (ATC) and the Oldsmobile Comfortron. These systens operate on conpletely different principles. By design, the Oldsmobile system operates in two nodes: heater mode or air conditioning mode. The Pontiac ATC operates in three modes: heater mode, air conditioning mode, or bi-level mode. Bi-level mode is a transitional mode between heater and air conditioning in which air is directed through both heater and air conditioning outlets. . Each of these illustrative differences between systems is small individually, but when one considers the total difference between the systems, the picture changes. Though the systems are supposedly comparable, they are each the product of individual engineering judgment and decision and are thereby different devices. I If the systems supported identical features, then a cost conparison could be extremely meaningful. But, since the systems are so different in the number and nature of features that they support the significance of a direct dollar-for-dollar conparison is lost. The scope of this thesis has, therefbre, been narrowed to cover the following considerations: I. PRODUCTION INSTALLATION ADAPTABILITY A. Labor time 8. Production repair considerations C. Nunber of discrete conponents and connections II. SERVICEABILITY A. Service problens B. Trouble shooting considerations C. Component accessability The fellowing systens were chosen because they represent a cross section of the three different automatic systems now produced in the General Motors Corporation. They are: l. Oldsmobile Comfortron This system is a descendant of the original Cadillac system. It is closely related to the systems now built by Chevrolet and Cadillac and uses themistor sensing and vacuum actuation. 2. Buick Automatic Climate Control This system is built only by Buick. It uses bi-metal tempera- ture sensing and vacuum actuation. 3. Pontiac Automatic Temperature Control This system is produced only by Pontiac. It uses thennstor temperature sensing and electric motor servo actuation. Other systems which are now under development were considered fer inclusion in this list but since information is incomplete on these systems, they were not included. This work was undertaken under the auspices of and in c00peration with the Product Engineering Department of Oldsmobile Division of General Motors Corporation. It is part of the final phase of a five year engineering program involving a four year c00perative work-study program at General Motors Institute and a one year graduate program at Michigan State University. It is intended to be used, in part, as a guide to future product develOpments at Oldsmobile. The following chapters describe each of the above systens individ- ually and in detail. Following that, a comparison of the systems is made with regard to their production and service characteristics. Finally, some conclusions and recommendations are made. I. OLDSMOBILE COMFORTRON Oldsmobile first produced the Commertron during the 1966 model year. It was a direct descendant of the Cadillac Comfort Control, the original automatic air conditioning system, first produced in 1964. This system'was engineered by Delco Radio Division, General Motors Corporation. The present Commertron is an evolved version of the 1964 system in that only small changes have been made in the system to improve its perfbrmance. This chapter describes the 1969 nodel year Comfortron in detail as it is installed in the Oldsmobile "98" series. The Comfortron is an electrical-vacuum, feedback servomechanism. It is designed to assume the task of maintaining the enviromental temperature within the car at some preset comfort level between 65° and 85°F. The system is designed to support the fbllowing operational features in order to attain and maintain the temperature level. 1. Outlet air temperature - from full heated air to full cooled air 2. Fan speed - give unique fan speeds in each of two ranges 3. Mode - outlet air distribution a. Heater b. Air conditioning .c. Defrost 4. Inlet Air Source a. 100% outside air b. 20% outside air - 80% recirculated air 5. Dehumidification - at ambient temperatures above 33°F 6. System start-up delays a. Cold weather start- -up delayed until engine coolant tenpera- ture reaches 120°F and cold air from ducts purged b. Harm weather inmedi ate start-up 7. Deice - start-up delays are by-passed and system drives to full heat, high Speed fan. 8. Heater water shut-off - to enhance maximum cooling performance 9. Output stabilization - Under insufficient vacuum supply condi- tions (e. g. ., upon heavy acceleration) the system locks to pre- vent erroneous output changes. The information flow in the System is diagramed in Figure 2 (Page 9). The diagram is specifically about the Oldsmobile Comfortron but the Buick Automatic Climate Control and Pontiac Automatic Tenperature Control, described in the following two chapters, Operate using the sane basic information network. These two systems are, however, different in the features which they support to achieve the desired control. Infermation entering the control mechanism represents prevailing tempterature conditions and the driver's wishes. The control mechanism reacts, producing a predeternnned set of output conditions such as out- let air temperature, fan speed, etc., in order to match the conditions - with the driver's wishes. Most of the output takes the form of condi- tioned air entering the system. There is, however, a nnnor feedback loop through the tenperature door potentiometer. This loop feeds in- formation to the control mechanism representing outlet temperature. The sane information would eventually reach the control in terms of in-car tenperature, but, Since in-car tenperature changes so slowly, FIGURE 2 Lgnalmnsnfl L_nlsal f] Lunauxsuu ] [gain-MI. INFORMATION FLOW THROUGH THE COMFORTRON SYSTEM TO the desired temperature nay be overshot. Therefore, this feedback loop allows the system to approach the desired in-car temperature in a more nearly optimum manner. It can be noted that some systems also perform the same function by electrically measuring actual out- let air temperature. This leads to difficulty in that different outlets are used under different circumstances so that no one outlet consistently represents outlet temperature at all times. Repeating, the main information flow is through the in-car air temperature. The in-car temperature is affected, however, in other ways than just by the output of the system. Radiant energy from the sun enters through the windows and convection and conduction occurs especially at high road speeds. These influences are translated into changes in overall in-car tenperature thereby effecting a conpensating change in the state of the control mechanism. The control system also receives infbrmation which controls the initial start-up of the system. At ambient temperatures below about 70°F, when the system would normally demand heat at start-up, the system will not start automatically until the engine coolant has reached a temperature of 120°F. Until then, no heat is available to warm the car so there is little point in starting the system blowing cold air. A delay of about 15 seconds is made to allow time for the heater core to warm up and for cold air in the ducts to be purged slowly to prevent an unpleasant cold blast. In warm weather, when cooled air is desired at start-up, the system starts almost immediately. The following is a detailed description of each of the components in the Comertron Control System. The components are connected as Shown in the following figure, Figure 3 (Page 11) - Vacuum Circuit Diagram, and ll . 526W BfiLX 55m“. 838 .58.; «on: «.55. '55.. l m. a j 258» ; magma... FHWP. \ 355.. 53>H£ fl u S3658 m \ \ll u \ e 5.: fr 1 1 L \ \ \ x 3.3 a: x v.2: 322 u \ \ 551%; 52:3 m 3.2: .58; 2211:; 3 n \ 55m “2:; r X \ 55 33 u f 65.. J m , ill\ ‘ E : : SEES: F «8e m: 5:; :3 e: 0e , >5: .2; F I 1'52.an m MW \\Lc<_ IIIJ g (l \\\\\\\\\ \ 1K(\\\ \ L eecflwwmwwmv top—3m 555‘ up}; COMFORTRON VACUUM CIRCUIT DIAGRAM FIGURE 3 12 COMFORTRON ELECTRICAL CIRCUIT DIAGRAM FIGURE 4 13 Figure 4 (Page 12) - Electrical Circuit Diagram. Reference to these figures as well as other figures as sited in the text will aid in understanding the operation of the system. Control Panel (Figures 5 [Page 13] and 6 [Page 14]) The control panel, located in the instrument panel to the left of the steering column, contains the fellowing: 1. Control lever, vacuum valve, and switches Temperature control dial and rheostat Amplifier In-car sensor 01-th . Thermostatic vacuum valve (Inside car) compassson _ swncn KTHERAMDSIATIC K‘MACUUWIVALVE (OPENS AT 70° F .I IUANGE RHEOSTAT I I s .. I I 39C. 'V ..mo—~ " TWPERATURE DIAL FIGURE 5 COMFORTRON CONTROL PANEL CONKCTOR // mama: 9' \anmune SUDIW// DIN. LEVER [ (8011M VIEW) FIGURE 6 COMFORTRON CONTROL PANEL - BOTTOM VIEN The control elements (#1 and #2 above) will be described here. The others are described under their own headings. The control lever can be placed in five positions: OFF With the control lever in OFF position, the vacuum is shut off and the system is inoperative. L0 - With the control lever in L0 position, vacuum is supplied to the system through the vacuum valve (Figure 6). The systenuwill start if the engine coolant is above 120°F, or the inside of the car is 70°F. The blower will automatically run in one Of the five low range blower Speeds and the temperature will be automatically controlled by the temperature control setting, and the outside and inside air temperatures. HI - With the control in H1 position, the systenlwill Operate just as it does in L0 position except that the blower will Operate in the five high range blower speeds. DEF Hith the control lever in DEF position, the systenlwill Operate just as it does in HI position except that the mode door directs air only to the heater ducts and the defrost door Opens. Approxinately 80% 15 Of the air goes to the defroster outlets and 20% goes to the heater outlets. Note that the system is still on automatic temperature control SO that either hot or cold air may come from the defroster outlets as the system dictates. DE-ICE - Hith the control lever in DE-ICE, vacuum is immediately ap- plied to the system regardless Of air or engine coolant tempera- tures. A contact on the range Switch closes fOrcing the system to full heat and highest blower Speed. Note, the system is no longer on automatic control. This is the only lever position in which the system*will start immediately, irrespective of any other condition. The vacuum valve is positioned by the control lever. It controls the vacuum supply and directs vacuum as necessary to make the system operate in the desired way. There are also two switches on the control panel. The conpressor switch supplies power to the compressor clutch circuit when the control lever is in any position except OFF. The ambient switch (described later) then turns on the conpmessor at any outside air temperature above 35°F. The range switch controls high and low range blower Speeds and fOrces the system to full heat in DE-ICE position as described befOre. The temperature dial is calibrated in temperatures between 65°F and 85°F. It should be set at a comfortable temperature (about 72°F normally, but it may vary with individual preference) and only small changes Should be necessary tO maintain comfort. The system‘will_auto- natically work at maximum effort to attain and hold the desired temperature. The rheostat is directly coupled to the temperature dial. It is a resistance input to the amplifier used to set the desired temperature. 16 SENSORS There are two temperature sensing elements in the system; they are in the in-car air sensor and the ambient (outside) air senSor. The temperature door position potentiometer, Figure 7 (Page 16), also serves as a temperature indicating device in that it indicates temp perature door position, which is analog to outlet temperature. The temperature door potentiometer, mounted on the Power Servo, is connected to the temperature door linkage and mechanically provides resistance in the sensor circuit in relation to the discharge temperature. SCREW FIGURE 7 TEMPERATURE DOOR POTENTIOMETER The in-car ambient sensors are thermistors, temperature sensitive resistors, whose electrical resistance varies inversely with temperature. That is, as their temperature goes up, their resistance goes down. Table 2 (Page 17), shows the relationship between sensor temperature and electrical resistance. TABLE 2 17 SENSOR RESISTANCE VS. TEM’ERATURE cwécxmo sensor nesusuwce Approximate Resistance in Ohms (1‘. 5%) Outside Sensor Sensor on Control Temp. Ohms Ohms 60° 44 95 65° 41 86. 70° 38 76 75° 36 68 80° 34 60 85° 32 55 90° 30 50 95° 27 45 100° 23 4O The in-car sensor, located in the control panel, Figure 5 (Page 13), has air from the inside of the car_drawn over it through a grill in the panel so that it senses in-car temperature. The anbient sensor nounted in the blower inlet duct, Figure 8 (Page 17), senses the tenperature Of the outside air entering the system. Figure 16 g FIGURE 8 AIGIENT SWITCH AND ANBIENT SENSOR 18 The sensors and the temperature door>potentioneter are wired in series with the temperature dial rheostat to form a voltage divider network. As temperatures vary, the total series resistance changes, supplying a variable voltage to the input Of the amplifier. Changes in in-car temperature produce a compensating change in the system output to return the in-car temperature to the desired level. Changes in ambient temperature are sensed so as to quickly affect changes in system output tO compensate for differences in inlet air temperature and also for changes in conduction and convection losses. AMPLIFIER The anplifie'r, mounted on the control panel, Figure 6 (Page 14), is a two transistor, Direct Current, amplifier. Its input is the resistance from the temperature rheostat and the sum Of the resistances in the sensor string. Its output is a variable current signal to the transducer. It also has a special input controlled by a contact on the range switch, which fOrces the system to full heat in DE-ICE Operation. TRANSDUCER The transducer, Figure 9 (Page 19), is an electrical-vacuum device which converts the current output signal from the amplifier into a regulated vacuum Signal which activates the Power Servo. 19 FIGURE 9 TRANSDUCER It contains a fOrce Operated vacuum valve which is activated by a wire loop element as shown in Figure 10. The wire elenent is a special FIGURE 10 TRANSDUCER DIAGRAM 20 material with a high thermal expansion coefficient. It is heated by the current Signal from the amplifier. I The valve balances two forces, the force due to the difference between atmospheric pressure and the partial vacuum in the system, and the force due tO the wire element. High current levels heat the element cauSing it to expand and relax the force on the valve. The opposite Occurs at low current levels. At high current levels, the regulated vacuum is high and at low current levels, regulated vacuum is low. POWER SERVO The power servo, Figure 11, is mounted on the top, right side of the heater assembly. It contains a vacuum diaphram assembly which is controlled by the regulated vacuum from the transducer. The vacuum diaphram operates the temperature door linkage, and the blower speed switch which is a circuit board and wiper contact assenbly, and a rotary vacuum switch. FIGURE 11 POWER SERVO 21 The power servo normally Operates near center travel Of the vacuum diaphram travel. The temperature door is positioned at about mid-travel and the blower Speed is on low. Increased vacuum drives the power servo toward higher heat. The temperature door assumes a position which mixes more warmed air and less cooled air. The vacuum valve forces heater mode which distributes air to the heater outlets if the system*was not in heater mOde already. As the servo moves, father toward full heat, the blower Speed switch turns the blower to four successively higher speeds until at full heat, the blower is at full Speed. Reduced vacuum moves the vacuum diaphram the other way. Air con- ditioning mode is assumed wherein outlet air is distributed to the air conditioning outlet. Again, higher and higher blower speeds are selected. At full cold position, the vacuum switch turns Off the heater water valve to enhance the maximum cooling capability Of the system. AS previously described, the temperature door potentiometer is mounted on the power servo. THERMOSTATIC VACUUM VALVE (Inside car) Figure 5 This vacuum valve, mounted on the control panel, Opens to start the systennwhenever the in-car temperature is above 70°F. Figure 12 (Page 22) shows a typical thermostatic vacuum valve. It contains a special wax pellet which expands and contracts with changes in temperature. 22 FIGURE 12 TYPICAL THERMOSTATIC VACUUM VALVE THERMOSTATIC VACUUM'VALVE'IWATER VALVE) Figure 14 This vacuum valve, mounted on the heater’water valve, Opens to start the system during cold weather when the engine coolant reaches 120°F. It is much the same as the Thermostatic Vacuum Valve on the inside of the car except that it is calibrated at 120°F instead of 70°F. VACUUM MASTER SWITCH This vacuum Operated switch is mounted in the engine compartment adjacent to the blower motor. It applies power to the blower motor cir- cuit when any_of the fOllowing conditions are satisfied: a. The Thermostatic Vacuum Valve on the heater water valve Opens g: L203: Eggine water temperature, and the control lever is b. The Thermostatic Vacuum Valve on the control panel Opens at 70°F in-car temperature and the control lever is in HI or L0. c. The control lever is in DE-ICE position. 23 AMBIENT SWITCH Figure 8 The ambient switch, mounted with the ambient sensor in the blower inlet duct, is closed at temperatures above 35°F. It supplies power to the air conditioning compressor clutch whenever the system is on so that the air conditioning condenser will cool all incoming air to just above freezing to dehumidify it. At temperatures below freezing, the water from the air would freeze on the condenser so the air conditioning system is turned Off. RANGE RELAY The range relay is located in the engine compartment next to the voltage regulator. When the control lever is set in the HI position, the range relay is energized, allowing the blower circuit to draw power directly from the junction block. This by-passes a fixed resistance in the LO range blower circuit and causes the blower to operate in one of the five, automatically selected blower Speeds. On cars with electric rear'window defogger Option, the range relay cannot be energized when the defogger is operating, preventing excessive powardrain. The blower'will then Operate only in the low range speeds. VACUUM RELAY The vacuum relay, located in the passenger compartment, allows regulated vacuum to pass from the transducer to the power servo as long as sufficient engine vacuum is available to run the system. When the en- gine vacuum drops, as on hard acceleration or when climbing a hill, the vacuum relay seals, locking the power servo in its current position. 24 VACUUM TANK The vacuum tank, located in the engine conpartnent, is used to store engine vacuum for the system. It has a check valve integral with it to preVent vacuum loss during periods of low vacuum supply. ASPIRATOR Figure 13 The aspirator is attached to the bottom Of the heater case and is located just ahead Of the mode door. Whenever the blower motor is opera- ting, air is drawn through the aSpirator, aspirator hose, and in-car sensor tube located on the control (Figure 5 [Page 13]). The air is drawn over the in-car sensor through the instrument panel from the in- terior of the car. FIGURE 13 ASPIRATOR LOCATION OUTSIDE AIR DOOR The outside air door, nounted in the blower assenbly in the engine conpartnent, controls the source Of air entering the system. It is de- signed to assume three positions. 25 a. OFF - Door closes out outside air (control lever in OFF). b. Production Recirculation - Door opens partially to admit approximately 80% recirculated air and 20% outside air (automatically selected by the system at full air condi- tioning to improve cool-down perfOrmance). c. Full Outside Air - 100% fresh air. DEFROSTER'DOOR The defroster door, located in the heater assembly, Opens to pass about 80% Of the heater air through the defroster outlets. It is de- signed tO assume only two positions and should activate whenever the control lever is in DEF or DE-ICE. MODE DOOR The mode door, located in the heater assembly, directs air to either the air conditioning or heater ducts. It is designed to assume only these two positions. TEMPERATURE DOOR A door in the heater assembly, controlled by the Power Servo, con- trols the tenperature of the air coming out Of the air outlets. This door can assume any position from full heated air to full cooled air. WATER VALVE Figure 14 The water valve, mounted in the engine compartment, is in the engine coolant to heater core line. It is actuated only when the system goes to full air conditioning and it stops engine coolant flow to the heater to inprove cool -down performance . 26 i} - 2: . m VACUUM vuvr FIGURE 14 WATER VALVE DIAGRAM LEAK DOWN PLUG The leak down plug is a sintered metal plug attached to one part of the vacuum master switch. It is used to leak vacuum from the system when the supply is turned Off, thereby opening the vacuum master switch and stOpping the system. RESTRICTOR PLUG The restrictor plug is a calibrated restrictor in the purple hose to the Thermostatic Vacuum Valve. Its purpose is to delay blower motor start about 15 seconds, when the system starts, requiring heat output. This is done to allow the heater core time to warm. It also allows the air conditioning evaporator to cool to reduce outlet air humidity. BLOWER RESISTORS The blower resistors are a group of wire coil resistors mounted to- gether near the blower assenbly in the engine compartment. They are switched into and out of the blower motor circuit by the blower program 27 switch in the power servo and by the range relay tO provide the various blower Speeds. The following figures illustrate the positions and interconnections between the components in the car. Previous reference has been made to these figures and future referral will be helpful during description of sequence Of Operations of the system. 28 m>._< 2k; E53 «82325:.» 3 55¢ 9...: «0.8 _ Em .\.. .1. DC I .c., zo<§amm< /¢u>5... £11.30me m. L «95.5.: v.25 §:o<> b“ L I I I ......M .3255 <3; «an ..l./. o>mmm 538 $520<> “23.50 3.13 2...... 25.. xzjm 2350 HE mam xzfim 25. w.— _ :3 xufim “NMQMON «38 .oz :8 £53. a COMFORTRON VACUUM HOSE CONNECTIONS FIGURE 15 W. :4 50.3 22522. was“. 32¢ on . e ,7. .. / .52 >53. 53.3 20.: ’ ' u ' \ ' , . \ . - ‘ k l . .\ ‘ ‘ ll. \ I. 1 I I - ENGINE COIPARTMENT CONNECTIONS FIGURE 16 30 SENSOR \‘ .’ I“ necroa {i5 “4/ mmsoucm COMPRESSOR I .. ma. SWITCH ASSY FIGURE 17 INSTRUMENT PANEL HIRING For the purpose of illustration, the following sequences of opera- tion are included in the text. These sequences are by no mans meant to cover all possibilities. They will, however, lead to a greater understanding of the interaction of the couponents. CASE l Initial Conditions The car has been exposed to a tenperature of 20°F for a period of tine sufficient to allow the entire vehicle to stablize at that tenperature. Sequence of Operations 1. The driver enters the car, starts the engine, turns the Com- fortron control lever to HI, sets the tenperature dial to 72°F, and drives off. ‘ 2. Vacuum is supplied to both Thermstatic Vacuum Valves, but they are both closed so vacuum is not supplied through them to the Vacuum Master Switch or any of the door diaphrams. 31 Vacuum is supplied, however, to the Transducer whenever vacuum is available. Also, electrical power is supplied to the sensor string and amplifier. So, the control system senses the need for heat to warm the car to the desired temperature and drives the Power Servo to the full heat position. The temperature door is, therefore, in the full heat position, the vacuum is ready to set the mode door in heater mode position, and the fan Speed switch is in the high speed position. At some time, the engine coolant passing through the heater ,water valve, reaches 120°F and the Thermostatic Vacuum Valve mounted on the water valve opens. Vacuum is then applied to the master switch through the restrictor plug. The restrictor plug slows the closing of the electrical contacts in the master switch while allowing the outside air door to open. This is done to allow the cold air in the system to be purged slowly. The air conditioning evaporator also starts to cool, at am- bient temperature above 35°F, reducing the outlet air humidity. The vacuum level builds, after a few seconds. to where the electrical contacts close. This applies power to the Come pressor Switch, Range Switch, and'the Blower Circuit. The Compressor Switch would supply power to the compressor clutch except that the Ambient Switch is open at ambient temperatures below 35°F. Since the control lever is in H1, the range switch applies power to the range relay, closing it and placing the blower in high range. The blower starts on highest Speed with the temperature door in full heat position and the car begins to warm. Eventually the interior of the car warns and the system begins to sense a balanced condition between desired and actual in- car temperature. The Transducer reduces the vacuum level to the Power Servo which moves the temperature door away from full heat and begins reducing the fan speed. The system finally senses that the desired temperature has been reached, the fan Speed is on low speed, high range, and the temperature door is near center with the air coming out the heater ducts just warm enough to maintain the desired_ temperature. The system has reached the desired temperature about as fast as possible without overshooting the goal. It continues to sense small differences between desired and actual tenperatures and makes appropriate output changes to elinfinate the difference. The driver may opt at any time to place the control lever in L0 which will place the blower Speed in low range. but the speed within that range will still be automatically selected. CASE 2 32 Initial Conditions The car has set in the sun with the windows closed for a period of time at an ambient temperature above 90°F. The interior of the car has reached high temperatures and the interior surfaces are uncomfortable to touch. Sequence of Operations 1. The driver enters the car, lowers the windows, starts the engine, sets the control lever at HI. and drives off. The Thermostatic Vacuum Valve in the car is open already, so vacuum is applied to the master switch, starting the fan in high range. The system senses the need for cooled air and so reduces vacuum to the Power Servo driving it to full cold position. The vacuum valve on the Power Servo selects air conditioning mode and the blower speed moves to highest Speed. The ambient switch is closed, starting the compressor. The vacuum switch, at full cold position, moves the outside air door to recirculate position so air recirculates through the system and cools more efficiently. It also closes the water valve to stop heated water to the heater core so that less heat is transferred into the system, thereby enhancing the cooling capacity of the system. As the system starts to cool, the driver shuts the windows. The temperature begins to approach the desired temperature and the system begins to throttle back, first by opening the water valve, then by going from recirculate to full outside air. The fan Speed reduces and the temperature door moves toward center as the temperature approaches the desired temperature. Finally, with the desired temperature reached, the systenlbegins to make small changes necessary to maintain the desired temperature. II. BUICK‘AUTOMATIC CLIMATE CONTROL Buick first produced the Automatic Climate Control during the l966 model year. The systenlwas designed and built by Harrison Radiator Division of General Motors Corporation specifically for Buick. The system was a thermo-mechanical system using capillary sensing elements. These sensors are glycol filled tubes located so as to sense temperatures in three locations: in-car. ambient. and duct outlet. The glycol expanded and contracted with temperature changes and the netr effect of all three sensors was used to drive a piston. The system then employed mechanical and vacuum means to adjust outlet air temperature and fan speeds to achieve the desired in-car temperature. The following model year, 1967, Buick started using a different system which was also designed and built by Harrison Radiator Division. This system is the predecessor of the current system. This chapter describes the 1969 model year Buick Automatic Climate Control System. The Automatic Climate Control is a mechanical, vacuumrfeedback control system. It is designed to be capable of maintaining the environ- mental temperature within the car at any desired temperature between 65°F and 85°F. 5 The system supports the following features as means to attaining and keeping the desired temperature level. 1. Outlet air temperature - from full heated air to full cooled air. 33 34 2. Fan Speed - five different fan Speeds in each of two ranges. 3. Mode - outlet air distribution a. Heater b. Air conditioning c. Defrost 4. Inlet Air Sources a. lOO% outside air b. 20% outside air - 80% recirculated air 5. Dehumidification - at ambient temperatures above 35°F. 6. System start-up delays a. Cold weather start-up delayed until engine coolant tem~ perature reaches lOO-l20°F and until cold air is purged from ducts. 7. De-ice - start-up delays are by-passed and fan goes to highestII speed, but system remains in automatic tenperature control. 8. Heater water shut-off - to enhance maximum cooling performance. 9. Output Stabilization - During periods of low vacuum supply (e.g. upon heavy acceleration) the system locks to prevent erroneous out- put changes. Reference to Figure 2 (Page 9) will Show basically how the control information flows through the Automatic Climate Control. As was men- tioned before. that diagram is specifically about the Oldsmobile Com- fbrtron system, but it also applies to the Automatic Climate Control with the fOllowing exception. No feedback loop exists to indicate out- let air temperature. ‘This function is performed by the temperature door potentiometer in the Oldsmobile system. The information flows are otherwise the same . The following is a Specific description of each of the components in the BuiCk Automatic Control, Figure l8 and Figure l9 (Pages 35 and 36) 35 the vacuum and electrical circuit diagrams on the fOllowing pages show the interrelation of the pieces. 80»(DhU( «000 «wthEmo 7 30.223 9.05.8.5” w>d(> waIU .3523 86.: 33. has 832.... 300E Spgmm o o v n « m3: OQOQQG , 2093: use 23080 305w» Shgmku ‘ isSU<> 41L ”‘3; ”a? KUSO g 5.... \ 99.33 N )1. 53:29.0 2003 \ v05. 53.. 3.50» at: l .- wa¢0 85h (<32) «80 #32. 82 3—(2U( _:W / J g at; f .\ (3‘ w>.—<> cw»(3lw>..<> §:U(> 2.35018th AUTOMATIC CLIMATE CONTROL VACUUM CIRCUIT DIAGRAM FIGURE 18 36 .8800 80:.» (~3040 CUhtux. 8.03. N. J (:3. a 3.29.285.“ a _ E H 331.33 932.2: 9:53 H 9.35 no ¢ :33; 5:3 8 a 8.. a. 1 _ . 32.3 «9533 . Sauna- B. J 3.5.. 33 .228 .325... aaaaa mtg! Sill) use; was: 00. 8 ..J .. :Il II’OC. N. u u so. .8 a ONC N. sauce. .8! «r6 in Sat: b 382.38 puaaoco 2.2233 .3 o. J r L' z: o. J 38.. . IT'S-32232 u» o 52:32.. !i\ a pig 1. uuco H. Jlfl . 32:3 1 .. :35» 5’30 3:. 2...... be. am. 1. 3.23333 .3 ... min-...? . — .8»..- U? n ...J-fll .J A L FL «— d! L I :32. 3. Q .... h .8»...- 55:. _ was! AUTOMATIC CLIMATE CONTROL ELECTRICAL CIRCUIT DIAGRAM FIGURE 19 37 CONTROL PANEL The Control Panel is mounted on the instrument panel to the left of the steering column as shown in Figure 20. It has two control levers, FIGURE 20 INSTRUMENT PANEL CONNECTIONS a temperature lever calibrated from 65°F to 85°F, and a selector lever marked OFF-LO—HI-DEFOG-DEICE as shown in Figure Zl (Page 38). The tenh perature lever is connected to a Bowden cable which mechanically transmits A the desired temperature to the Thermostatic Vacuum Regulator, the main control component. A Bowden cable consists of a wound wire tubular sheith with a stiff wire running axially through it. It is capable of trans- mitting motion along the wire. The Control Panel also contains the Selector Vacuum Switch and the Selector Electrical Switch. They are connected to the selector lever. They control the Operation mode of the system. OFF LO HI- DEFOG DEICE 38 8! ("II dm W W mu TIIPIIIIIII Dill II N 75 I I5 I. I u I____ m FIGURE 21 CONTROL PANEL The system behaves as follows in each control lever position: The system is inoperative with the blower off and outside air door closed. The system is under automatic temperature control with the fan in one of the five automatically selected low range Speeds. System start-up delays are in effect. No high blower speed exists in maximum air conditioning in L0 pos tion. The system behaves much as it does in L0 position except that the blower is in one of the five automatically selected high range Speeds . System is in H1 range except heater mode is mandatory. The defroster door is also actuated so that the majority of the air goes to the windshield. Note, that air may be hot or cold as the system dictates. The systeuioperates as in DEFOG range except that highest blower speed is mandatory. System start-up delays are by-' passed only in DEICE position. THERMOSTATIC VACUUM REGULATOR The Thermostatic Vacuum Regulator is the main control component in the systenn It receives information on desired temperature from the Bowden cable to the control, ambient air tenperature, and breath level (also called in-car) air temperature and produces a controlled vacuum level output which governs the operation of the system. 39 l The sensors are bi-metalic strips such as are connnnly found in household thermostats. They are linked as shown in Figure 22 to the ball bleed valve. Ambient air is ducted to the Thermostatic Vacuum Regulator and passed over the ambient bi-netal strip. The ambient air passing through also automatically aSpirates in-car breath air through a tube from the dash and over the breath bi-metal strip. The strips react to the ambient and breath air temperatures and being linked together, act in unison to fOrce the ball valve to seat. The ball valve balances the force due to the difference between the atmospheric pressure and regulated partial vacuum and the net force of the bi-metal strips. RESTRICTOR . . - ;/ MANIFOLD I REGULATED VACUUM J VACUUM AMBIENT [/1 “R ' AMBIENT BI-MET AL BALL VALVE BLEED i \ BREATH Bl-METAL BREATH AIR . FIGURE 22 THERWSTATIC VACUUM REGULATOR SCHEMATIC Should the manifold vacuum rise, the ball valve would be forced off its seat farther thereby leaking more air and tending to maintain the regulated vacuum level. If the force fronione bi-metal strip should rise, the ball valve would be fOrced farther into its seat causing less air leakage. This would result in'a higher regulated vacuum level to keep the net force on the ball at zero. 4O ADJUSTER SCREW AMBIENT (—- O BI-MET AL \ f I BREATH CLEAN FILTERED | ”METAL AIR I BALL BLEED VALVE GE .. _ _ - - ._ : : ... -.. REGULATOR VACUUM ' ‘1. :z’ ‘ TO PVA Mummtno IEGUUHED VACUUM VACUUM RELAY DIAPHRAGM (RESTRUOR) 13—412 FIGURE 23 THERMOSTATIC VACUUM REGULATOR CROSS SECTION Figure 23 shows a cross section of the Thermostatic Vacuum Regula- tor. The air that bleeds by the ball valve is filtered to keep the ball from being contaminated. I The Regulated Vacuum Relay is also integral with the Thermostatic Vacuum Regulator. Its function is to lock the regulated vacuum level during periods of low vacuum supply so that the system output does not change erroneously. When the manifold vacuum level (supply) drops below the regulated vacuum level momentarily, the relay seals the outlet port to the Piloted Vacuum Actuator. 41 The regulated vacuum is then applied to the Piloted Vacuum Actua- tor, the control element as shown in Figure 24. TEMPERATURE DOOR AIR I . - 5 COND. \ MANIFOLD REGULATED 7 \ HEATER VACUUM VACUUM . )l AMBIENT BI-METAI. BREATH BI-METAI. PILOTED . VACUUM ACTUATOR 13-410 FIGURE 24 REGULATED VACUUM APPLICATION SCHEMATIC PILOTED VACUUM ACTUATOR The Piloted Vacuum Actuator balances a fOrce due to the regulated vacuum from the Thermostatic Vacuum Regulator against a Spring force giving a linear actuation which operates the temperature door as shown in Figure 24. It is not, however, a simple vacuum diaphram as Shown in the I figure. It is a two-diaphram unit. The regulated vacuum controls a pilot diaphram and engine vacuum is used to drive a power diaphram. The unit is shown in cross section in Figure 25 (Page 42). Regulated vacuum from the Thermostatic Vacuum Regulator determines the position of the pilot diaphram. Engine manifold vacuum is applied to the right-hand side of the power diaphram pulling it away from the pilot diaphram. This opens the bleed hole in the center of power diaphram allowing air to flow 42 ATMOSPI‘ERIC AIR BLEED PILOT POWER DIAPHRAGM—~ DIAPHRAGM BLEED HOLE PVA STEM MANFOLD VACUUM REGULATED VACUUM FROM TVR ATMOSPHERIC AIR BLEH) I3 - ISO FIGURE 25 PILOTED VACUUM ACTUATOR through the atmospheric air bleed ports and the bleed hole into the vacuum. When the atmospheric air and bleed hole flow rates are equal, the power diaphram stops moving. Should the power diaphram move away fronthe pilot diaphram, the bleed hole opens more allowing the power diaphram to move back. Should it move too far toward the pilot diaphram, the bleed hole is restricted and the manifold vacuum pulls it back. The power diaphram floats a small distance from the pilot diaphram and in the event that the pilot diaphram moves in reSponse to changes in regulated vacuum level, the power diaphram follows. 43 MASTER SWITCH PVA RETAINER /’\ NUTS mu '\ .«I ." s C \ RETURN SPRING \ ‘ PROGRAM LINK \\ / PROGRAM VACUUM DISK SWITCH FIGURE 26 PILOTED VACUUM ACTUATOR INSTALLATION Figure 26 shows the mounting of the PilOted Vacuum actuator. Its power diaphram drives the temperature door linkage and is also connected to the Program Vacuum Disk Switch and Blower Switch. The Program Vacuum Disk Switch automatically selects the mode (heater or air conditioning outlets), changes the air inlet door, and shuts off the heater water. The Blower Switch controls the blower speed within the high or low range as selected by the driver. THERMOSTATIC VACUUM VALVE (on Water Valve) The Thermostatic Vacuum Valve opens to start the system in cold weather when the engine coolant reaches 120°F. 44 VACUUM MASTERSIIITTCII The Vacuum Master Switch can be seen in Figure 26 (Page 43). It applies power to the blower circuit when vacuum is applied to it in any of the following ways: a. The Thermostatic Vacuum Valve on the heater Hater Valve opens when the engine coolant reaches 120°F and the control lever is in L0 or HI. b. The Thermostatic Vacuum Regulator senses the need to go to air conditioning mode as during hot weather and the control lever is in L0 or HI. c. The control lever is placed in DEICE. AMBIENT SHITCH The ambient switch, mounted in the blower inlet duct, is closed at temperatures above 35°F. It supplies power to the air conditioning compressor clutch whenever the system is on SO that the air conditioning condenser will cool all incoming air to just above freezing to dehumidify it. At tenperatures below freezing, the water from the air would freeze on the condenser, so the air conditioning system is turned off. LOW RELAY The Low Relay is actuated by the selector switch in any position except OFF. This relay controls the main power supply for the blower circuit. A[C RELAY The A/C Relay is operated either when the Blower Switch goes to highest air conditioning fan speed in H1 range or the control lever is in DEICE position. It shifts the blower power supply from the Low Relay Circuit to a circuit connected directly to the battery. This is done 45 to by-pass most wire and contact resistances in the blower circuit thereby achieving highest possible blower speed. VACUUM TANK The Vacuum Tank, located in the engine compartment, Stores engine vacuum to maintain system operation during periods of low vacuum supply. OUTSIDE AIR DOOR The outside air door, mounted in the blower assembly in the engine conpartment, controls the source of air entering the system. It is de- signed to assume three positions. I a. OFF - Door closes out outside air (control lEVer in OFF) b. Production Recirculation - Door Opens partially to.admit approxi- mately 80% recirculated air and 20% outside air (automatically selected by the system at full air conditioning to improve cool- down performance) c. Full Outside Air - 100% fresh air DEFROSTER DOOR The defroster door, located in the heater assembly, opens to pass about 80% of the heater air through the defroster outlets. It is designed to assume only two positions and should activate whenever the control lever is in DEF or DEICE. mDE IDOR The mode door, located in the heater assembly, directs air to either the air conditioning or heater ducts. It is designed to assume only these two positions. 46 TEM’ERATURE NOR A door in the heater assembly, controlled by the Power Servo, controls the temperature of the air coming out of the air outlets. This door can assume a position from full heated air to full cooled air. WATER VALVE The Hater Valve, mounted in the engine compartment, is in the engine coolant to heater core line. It is actuated only when the system goes to full air conditioning and it stops engine coolant flow to the heater to inprove cool-down performance. SINTERED BLEED RIVET Hhen the engine is stopped and the engine coolant cools down, the vacuum is blead from the system by the Sintered Bleed Rivet to avoid immediate system start-up. The bleed down time is about l2-35 nfinutes. VACUUM RESTRICTORS There are several Vacuum Restrictors in the system. There is one in each part to the Master Switch to introduce a l5-3O second delay in blower start-up each time the blower is turned on to allow the system to drive to the position it will run in after the system starts. There is another restrictor in the engine vacuum line to the Piloted Vacuum Actuator. BLORER RESISTORS The Blower Resistors are a set of electrical resistances, switched sequentially into and out Of the blower motor circuit to change the blower speed. 47 The fOllowing operation sequences are included to assist the reader in understanding the Operation of the system. They are meant by no means to include all operational possibilities. CASE 1 Initial Conditions The car has been exposed to a temperature of 20°F for a period Of time sufficient to allow the entire vehicle to stabilize at that tenperature . Sequence of Operations I. The driver enters the car, starts the engine, turns the Automatic Climate Control tenperature lever at 72°F and the control lever at HI, and drives off. Vacuum has been supplied to the system so the Thermostatic Vacuum Regulator drives to full heat during the initial l5- 30 second delay. Since the system is at full heat, the immedgate start-up feature fOr air conditioning is by- passe . At some time the engine coolant warms to lZO°F and the Thermostatic Vacuum Valve on the Hater Valve opens. This applies vacuum to the door actuating diaphrams and Master Switch as directed by the system. The Master Switch is delayed 15-30 seconds by the restrictor plugs in its vacuum lines to allow the doors to get into position. The fan starts in highest speed. As the car warms to near the desired temperature, the System starts to throttle back by moving the temperature door to a nore moderate position and reducing the fan speed. As the system senses that the desired temperature has been reached, it is in low fan speed and the temperature door is to produce some warm outlet temperature to keep the interior warm. It is normal for this System to overshoot the desired temperature and cycle about it a few times as the system adjusts. The system stabilizes at the desired temperature and continues making adjustments to maintain that temperature. 48 CASE 2 Initial Conditions_ The car has set in the sun fer a period of time at an ambient temperature of 90°F. The interior of the car has reached a high tenperature . Sequence of Operations 1. The driver enters the car, lowers the windows, starts the engine, sets the control lever to HI, and drives off. 2. Vacuum is applied to the Thermostatic Vacuum regulator and, sensing the need for maximum cooling, it moves in that direction. As the system goes to air conditioning mode, vacuum is applied to the Master Switch and apprOpriate diaphrams thereby by-passing the start-up delay. 3. After 15-30 seconds, the Master Switch closes starting the fan in high Speed. Since the system is at maximum cooling, the Heater Hater Valve is Shut Off and the inlet air door is in the recirculate position. 4. The driver closes the windows and the interior starts to cool. 5. As the system senses that the in-car temperature is approaching the desired temperature, the system be ins to throttle back. The outside air door goes to full outsIIde air, the fan speed reduces, the temperature door goes toward center position, and the heater Hater Valve opens. 6. As the desired in-car temperature is reached, the fan speed is in low and the temperature door is situated to deliver cool air to the interior to maintain the desired temperature. III. PONTIAC AUTOMATIC TEMPERATURE CONTROL The Automatic Temperature Control was first installed by Pontiac in l967. The system was and still is unique in design in General Motors. It was desigIed by Delco Radio. The Automatic Temperature Control is an electro-mechanical feed- back servo system. It uses electrical sensing elements and an electric motor as the main control element. In this respect, it is unlike any other General Motors automatic air conditioning system. That is, it does not use regulated vacuum as a proportional control power source. It does, however, use vacuum to actuate door diaphrams. This makes the system much less sensitive to variations in engine load and speed conditions. The system supports the following features to attain and maintain a desired temperature level rapidly and accurately: l. Outlet air temperature - from full heater air to full cooled air. 2. Fan speed - five unique fan Speeds in each of two ranges. 3. Mode - outlet air distribution a. Heater b. Bi-level - air out both heater and air conditioning outlets. 4. Inlet air distribution a. lOO% outside air b. 50% outside air - 50% inside air c. lOO% inside air 5. Dehumidification - at ambient temperatures above 35°F. 49 50 6. System start-up delays a. Cold weather start-up delayed until heater core has heated to deliver warm air. 7. DE-ICE - Start-Up delays by-passed and system drives to full heat, high speed fan. 8. Heater water shut—off - to enhance maximum cooling perfOrmance. 9. Consistent start-up - system drives to near center position whenever power is turned off so that it always starts in low speed. Again, the information on Figure 2 (Page 9), is indicative of the infOrmation flow in the Automatic Temperature Control. The fOllowing figures are vacuum and electrical circuit diagrams. Reference to these figures will aid understanding the interrelationships between the components as described subsequently. 51 33 :2: 9 35:3 9.88 :55... HI . IIIII I. M _Cupwi ~38 ” Di... TIIIT- -me 5.241! I _ - a... "a“. . _IH C can» . fl _ . e g .w O .1 O ~c'_ AA ”M ‘1'” It), I I” A1 (v ._JI;§.}__: \‘ A 'V : on: Io; Moon: H—ir" :L 33"”: IE I! mum .l ”~00” 1” - T'I I I I l _L_ ”09"" UNIQU) p > who on IA! an Vt-I'IOI'U‘OII at u. ‘00-" C'VO on III. all“!!! It?“ TOO-“(W3 I TE “LOI— Li»— L. 1" Jr) In I L:- .IIIITIIIIL «852.3 2.. _ _ _ _ _ _ _ _ S . fl 3 3 m"..’ 23‘ _ Ff? MKLIQ $30.28.. 3.13 Isl-flag... 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