CA1136739A - Control system for a machine - Google Patents
Control system for a machineInfo
- Publication number
- CA1136739A CA1136739A CA000358428A CA358428A CA1136739A CA 1136739 A CA1136739 A CA 1136739A CA 000358428 A CA000358428 A CA 000358428A CA 358428 A CA358428 A CA 358428A CA 1136739 A CA1136739 A CA 1136739A
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- electromechanical
- machine
- timer
- motor
- control circuit
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- Control Of Electric Motors In General (AREA)
Abstract
A CONTROL SYSTEM FOR A MACHINE
ABSTRACT
A system for controlling a machine having a plurality of cycles of operation includes a plurality of selector switches for selecting a cycle of operation of the machine, an electromechanical timer for activating and deactivating a plurality of machine functions in a sequence of timed events determined by the selected cycle and a pro-grammable electronic control circuit for activating and deactivating the electromechanical timer in accordance with preprogrammed and selectively programmed instructions. The electronic control circuit includes a control logic unit having a preprogrammed set of instructions residing therein, a switch for selectively programming the control logic unit to delay the start of a selected cycle, and a plurality of input and output terminals. One input terminal of the electronic control circuit is coupled to the selector switches to indicate to the control logic unit that a predetermined cycle of operation having a time-expanded event has been selected. In a programmed delay, power is removed from the electromechanical timer in response to the electronic control circuit until the programmed delay time has elapsed.
ABSTRACT
A system for controlling a machine having a plurality of cycles of operation includes a plurality of selector switches for selecting a cycle of operation of the machine, an electromechanical timer for activating and deactivating a plurality of machine functions in a sequence of timed events determined by the selected cycle and a pro-grammable electronic control circuit for activating and deactivating the electromechanical timer in accordance with preprogrammed and selectively programmed instructions. The electronic control circuit includes a control logic unit having a preprogrammed set of instructions residing therein, a switch for selectively programming the control logic unit to delay the start of a selected cycle, and a plurality of input and output terminals. One input terminal of the electronic control circuit is coupled to the selector switches to indicate to the control logic unit that a predetermined cycle of operation having a time-expanded event has been selected. In a programmed delay, power is removed from the electromechanical timer in response to the electronic control circuit until the programmed delay time has elapsed.
Description
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The present invention relates to electromechanical timers of the type which include a main motor,- a plurality of cam surfaces which are movable in response to the main motor, a plurality of electrical contacts which are opened and closed by the cam surfaces, and a secondary motor for advancing the movement of the cam surfaces. More parti-cularly, the present invention relates to an electronic system for controlling the operation of the electromechanical timer.
Electromechanical timers of the general nature to which the present invention relates are well known to those skilled in the art and have been employed in appliances such as dishwashers, washing machines, and other machines to activate and deactivate various machine functions in a sequence of t'imed events determined by a cycle of operation of the machine which has been selected by the user. As generally indicated above, these electromechanical timing devices typically include at least one motor to rotate a plurality of disks, each of which have cam surfaces for openiny and closing a plurality of electrical contacts.
The machine functions are in turn activated and deactivated by the closing and opening of the various electrical contacts. 'Many of these electromechanical timers also include a secondary motor which, when activated, rapidly advances the movement of the cams to either expand or decreas'e the time period associated with a particular event of a selected cycle of operation of the machine. Where the timer includes a main motor and a secondary motor, a clutch is employed to disengage one of the motors while the other motor is operating to move the cam surfaces. Various e'lectromechan;cal schemes have been devised for extending or decreasing the time period of a particular event of a selected cycle. For example, these schemes may use the secondary or rapid-advance motor or intermittently remove power to the electro-- mechanical timer, With the increased recognition for the need to conserve :`
.
., ~L~L3ti,t739 energy, it is desirable to have appliances and other machinery ~hich consume large quantit;es of power to be operated during non-peak periods of power consumption. These non-peak periods of power consumption naturally occur when it is most inconvenient for the user of the appliance or machine to be present to activate the electromechanical timer.
The present invention provides a system for controlling the operation of a conventional electromechanical timer and allows the user of the system to program a desired time of day for activation of the electro-mechanical timer. Further, during a time-expansion mode of operation of the electromechanical timer, the duty cycle of the main ti~er motor is precisely controlled by the control system of the present invention.
In one broad concept, therefore, it is a feature of the present invention to provide a programmable means for control-ling the activation and deactivation of a conventional electromechanical timer wherein the programmable control means includes means for selectively programming a time of day when the electromechanical timer is activated and further includes a preprogrammed set of instructions for periodically de-activating the electromechan;cal timer to expand the time period of -at least one of the events of a selected cycle in response to selection ;~
of a predetermined cycle of operat;on by the user of the appliance or mach;ne.
` Accord;ng to the present invention, an electronic control c;rcuit for controlling the activation and deactivation of a conventional electromechanical timer includes a co~trol loglc unit having means for storing preprogrammed instructions and data and a plurality of input and output terminals. In response to being addressed by the operator of the appliance or machine, data is retrieved and the electronic control circuit operates the electromechanical timer ;n accordance with the preprogrammed ;nstructions and retrieved data.
The present invention relates to electromechanical timers of the type which include a main motor,- a plurality of cam surfaces which are movable in response to the main motor, a plurality of electrical contacts which are opened and closed by the cam surfaces, and a secondary motor for advancing the movement of the cam surfaces. More parti-cularly, the present invention relates to an electronic system for controlling the operation of the electromechanical timer.
Electromechanical timers of the general nature to which the present invention relates are well known to those skilled in the art and have been employed in appliances such as dishwashers, washing machines, and other machines to activate and deactivate various machine functions in a sequence of t'imed events determined by a cycle of operation of the machine which has been selected by the user. As generally indicated above, these electromechanical timing devices typically include at least one motor to rotate a plurality of disks, each of which have cam surfaces for openiny and closing a plurality of electrical contacts.
The machine functions are in turn activated and deactivated by the closing and opening of the various electrical contacts. 'Many of these electromechanical timers also include a secondary motor which, when activated, rapidly advances the movement of the cams to either expand or decreas'e the time period associated with a particular event of a selected cycle of operation of the machine. Where the timer includes a main motor and a secondary motor, a clutch is employed to disengage one of the motors while the other motor is operating to move the cam surfaces. Various e'lectromechan;cal schemes have been devised for extending or decreasing the time period of a particular event of a selected cycle. For example, these schemes may use the secondary or rapid-advance motor or intermittently remove power to the electro-- mechanical timer, With the increased recognition for the need to conserve :`
.
., ~L~L3ti,t739 energy, it is desirable to have appliances and other machinery ~hich consume large quantit;es of power to be operated during non-peak periods of power consumption. These non-peak periods of power consumption naturally occur when it is most inconvenient for the user of the appliance or machine to be present to activate the electromechanical timer.
The present invention provides a system for controlling the operation of a conventional electromechanical timer and allows the user of the system to program a desired time of day for activation of the electro-mechanical timer. Further, during a time-expansion mode of operation of the electromechanical timer, the duty cycle of the main ti~er motor is precisely controlled by the control system of the present invention.
In one broad concept, therefore, it is a feature of the present invention to provide a programmable means for control-ling the activation and deactivation of a conventional electromechanical timer wherein the programmable control means includes means for selectively programming a time of day when the electromechanical timer is activated and further includes a preprogrammed set of instructions for periodically de-activating the electromechan;cal timer to expand the time period of -at least one of the events of a selected cycle in response to selection ;~
of a predetermined cycle of operat;on by the user of the appliance or mach;ne.
` Accord;ng to the present invention, an electronic control c;rcuit for controlling the activation and deactivation of a conventional electromechanical timer includes a co~trol loglc unit having means for storing preprogrammed instructions and data and a plurality of input and output terminals. In response to being addressed by the operator of the appliance or machine, data is retrieved and the electronic control circuit operates the electromechanical timer ;n accordance with the preprogrammed ;nstructions and retrieved data.
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Further according to the present invent;on, the electronic control circuit provides a display of the t;me remaining before activat;on of the electromechanical timer, provides a signal to activate a switching device which removes power from the electromechanical timer during a programmed delay~ provides a signal to the rapid-advance timer motor which is act;vated to preposition the ma;n timer motor to the starting point when a delay has been programmed and provides a signal to the main timer motor for time expansion of an event of a selected cycle in response to an input received from the electromechan;cal t;mer.
A method of cbntrolling a mach;ne ;n accordance w;th the present invention includes the step-s of removing power from the machine functions and a main motor of an electromechanical timer, applying power to a secondary motor of the electromechanical timer to return the timer to its start position, counting down a selected time per;od, and at the end of the selected time period removing power from the secondary motor of the timer and applying power to the machine functions and the main motor of the timer to start a selected cycle of operation of the mach;ne.
While various features of the present ;nvention havé been described - above, other features and advantages will become apparent in view of the detailed description and drawings which follow in which: -Fig. 1 is a diagrammatic representation of a control system for a machine constructed ;n accordance with the present invention;
Fig. 2 is a partially functional and partially schematic diagram of the electronic control circuit employed in the system of Fig. l;
Fig. 3 is a flow diagram charting the steps of a method of controlling a mach;ne ;n accordance with the present ~nvention; and F;gs. 4-8 are deta;léd flow d;agrams of var;ous steps of the method functionally shown in Fig. 3.
In accordance with the present lnvention, the operation of an appliance or machine, such as a dishwasher, is controlled by an
Further according to the present invent;on, the electronic control circuit provides a display of the t;me remaining before activat;on of the electromechanical timer, provides a signal to activate a switching device which removes power from the electromechanical timer during a programmed delay~ provides a signal to the rapid-advance timer motor which is act;vated to preposition the ma;n timer motor to the starting point when a delay has been programmed and provides a signal to the main timer motor for time expansion of an event of a selected cycle in response to an input received from the electromechan;cal t;mer.
A method of cbntrolling a mach;ne ;n accordance w;th the present invention includes the step-s of removing power from the machine functions and a main motor of an electromechanical timer, applying power to a secondary motor of the electromechanical timer to return the timer to its start position, counting down a selected time per;od, and at the end of the selected time period removing power from the secondary motor of the timer and applying power to the machine functions and the main motor of the timer to start a selected cycle of operation of the mach;ne.
While various features of the present ;nvention havé been described - above, other features and advantages will become apparent in view of the detailed description and drawings which follow in which: -Fig. 1 is a diagrammatic representation of a control system for a machine constructed ;n accordance with the present invention;
Fig. 2 is a partially functional and partially schematic diagram of the electronic control circuit employed in the system of Fig. l;
Fig. 3 is a flow diagram charting the steps of a method of controlling a mach;ne ;n accordance with the present ~nvention; and F;gs. 4-8 are deta;léd flow d;agrams of var;ous steps of the method functionally shown in Fig. 3.
In accordance with the present lnvention, the operation of an appliance or machine, such as a dishwasher, is controlled by an
3-~L~L3~;~73~
electromechanical timer in conjunction with an electronic contro1 circuit which employs a microprocessor. In general, the electronic control circuit allows the operator of the machine to program a delay up to nine hours and fifty minutes before the electromechanical timer and the machine are activated. Furthermore, the electronic control circuit includes provisions for extending the time of a particular event of a cycle of operation of the machine upon receipt of a signal from the electromechanical t;mer that the mach;ne ;s ;n a tlme-extension mode of operation. ~-Referring in particular now to Fig. l, the control system lO of the present invention ;s d;agrammatically illustrated to show the relationship between the electromechanical timer and the electronic control circuit. While the control system lO will be described hereinafter with respect to its adaptation to an appliance such as a dishwasher, it will be understood by those skilled in the art that the control system lO could also be adapted to control other machines havlng a plurality of machine functions 12 which are activated and dèactivated in accordance with selected cycles of operation of the mach;ne. In an appliance such as a dishwasher, the machine functions 12 typically include motors, pumps, heaters, and relays. However, it is unimportant to the system lO of the present invention what functions are associated with the machine being controlled.
Many appliances are presently controlled by electromechanical timers or control devices l4 which, in accordance with cycle selection by the operation of the appl;ance, activate and deactivate the var;ous funct;ons associated with the dishwasher in predetermined sequences ; of timed events. For example, an electromechan;cal t;mer or control device 14 may be of the type M-520 manufactured by Mallory Components Group, Emhart Industries, Inc, Associated with these convent-ional electromechanical timers 14 is a main or timer motor (TM) 16, ~L3~ 3~
and in the M-520, a secondary or rapid-advance motor (RAM~ 18. Where a timer motor 16 and a rapid-ad~ance motor 18 are included in an electromechanical timer 14, a clutch 20 is included to engage and disengage the motors 16, 18 so that they are operable independently of each other. Each of the motors 16, 18 are mechanically connected to and, therefore, drive a plurality of disks or cams Z2, 26, 30, 34 and 38. Each of these cams has one or more cam surfaces (not shown) which open and close electrical contacts 24, 28, 32, 36 and 40, respecti-vely, as one of the motors 16, 18 rotates the circular cams 22, 26, 30, 34 and 38 to move the cam surfaces. A plurality of these cams 22, 26, 30, 34 and 38 are commonly referred to by those skilled in the art as a cam stack within the electromechanical timer 14. The electro-mechanical timer 14 also includes an internal power line 42 which is connected to one side of one or more of the electrical contacts associated with the various cams. Furthermore, a selector switch ` panel 50 is provided external to the appl;ance and includes a plurality of switches which allow the user of the appliance to select various optional cycles of operation for the appliance.
In operation, power is supplied to the electromechanical timer 14 through electrical contacts 36 of one or more cams 34 and the selector switches 50. Accordingly, when electrical contacts 36 are closed, electrical power is supplied through selector switches 50 to the power line 42 within the electromechanical timer 14, the timer motor 16, and a series of cams 38 and electrical contacts 40 to control the activation and deactivation of the machine functions 12. It should be noted that various numbers of cams 38 and associated contacts ~0 may be provlded within the conventional timer 14 to control the operation o~ the appliance or machine.
Continuing to refer to Fig. 1, an electron~c control circuit 60 for controlling the activation and deactivatlon of the electromechanical : . . . . .
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timer 14 includes means 62 for programming the electronic circuit 60, The programming means 62 includes a switch 64 ~or sett;ng a delay time or time of day when the electromechanical timer 14 is to be activated and a switch 66 for actuating the control system 10 The operat1On of the programming means 62 will be described in more detail later.
The control system 10 is connected to an AC, 120 volt power supply through lines Ll, L2 and a switch 70. In an appliance, switch 70 may be incorporated into a door so that when the door is closed switch 70 is also closed. The AC lines Ll~ L2 supply AC pawer directly to the electronic control circuit 60 and to a relay 72. Relay 72 includes two contacts 74, 76 and an arm 77 which is movable ~rom one contact to another by a solenoid 78. As illustrated in Fig. 1, the arm 77 of relay 72 normally engages contact 74 when solenoid 78 is not energized. Accordingly, AC line Ll is connected through the switch 70, - relay 72, and contacts 36 to the electromechanical timer 14 when the relay 72 is not energized. As long as cam 34 is in position such that contacts 36 are closed, power is supplied through the selector switches - 50 to the power line 42 within the electromechan;cal timér 14 and ultimately through cams 38 and switches 40 to the machine functions 12.
The electronic control circuit 60 also includes a bi-directional switching devic~ 80, such as a triac, having main terminals 82, 84 and a gate 86. Main terminal 82 of the triac 80 is connected through a connector 88 to the solenoid 78 of the relay 72 and main terminal 84 is connected to the AC line L2. As will be described in more detail later, when the electronic control circuit 60 has been programmed to delay the start of the electromechanical t;mer 14, triac 80 is activated and solenoid 78 ;s energized so that the arm 77 engages contact 76.
When arm 77 engages contact 76, the AC line Ll is connected through the switch 70 and the rela~ 72 to the contacts 25 of electromechanical timer 14. If the cam 22 associated with contacts 24 is in such a position , ~ -6-__. , .. ,.. , ... __ ,_ ~ , . .... .
, ~L13~739 that contacts 24 are closed, as illustrated, the secondary or rapid-advance motor 18 is activated to rotate the cams Z2, 26, 3a, 34 and 38 until contacts 24 are opened by cam 22, at which time the rapid-advance motor 18 is deactivated. When contacts 24 are openéd, the electro-mechanical timer 14 should be set in its start position. Accordinyly, it will be understood that if contacts 24 are opened when solenoid 78 is energized and arm 77 engages contact 76, the rapid-advance motor 18 will remain deactivated since the electrornechanical timer 14 is already in its start position. Importantly, when the arm 77 of relay 72 engages contact 76, power is removed from contacts 36 of the electromechanical timer 14 so that power is removed from the primary timer motor 16 and the machine functions 12. It can, therefore, be appreciated that if the rapid-advance motor 18 is activated through contacts 24 and the cams 22, 26, 30, 34 and 3~ are moved to set the electromechanical timer 14 in its start position, the machine functions 12 and the primary timer motor 16 will not be activated, even though some contacts and -- switches o~ the electromechanical timer may be closed, because power will have been removed from the contacts 36 by the relay 72.
The electronic control circuit 60 is also electrically connected to the electromechanical timer 14 through connections 90, 92 and 94 in the following manner. The electronic control circuit 60 includes ~-~
another bi-direc-tional switching device or triac 100 having main terminals 102, 104 and a gate 106. Main terminal 102 of the triac 100 is connected to the power line 42 within the electromechanical timer 14 through connection 92, and ma;n terminal 104 of triac 100 is connected to one side of the primary timer motor 16 throuyh connectlon 94. The gate 106 of triac 100 is connected to another bi-directional switching device or triac llO o~ the electronic control circuit 60. Triac 110 includes main terminals 112, 114 and a gate 116. Main terminal 112 of the triac 110 is connected to the gate 106 of triac 100 through ~ -7-.
113~'739 resistor 118 and main terminal 114 of triac 110 is connected to the AC
line L2. In the operation of control system 10, triacs 110, 110 intermittently activate and deactivate the primary timer motor 16 when a cycle has been selected from selector switches 50 which includes a time-extended-event. In one embod;ment of the control system 10, the electronic control circuit 60 is preprogrammed to activate the timer motor 16 for ten seconds of each minute of the time-extended event and deactivates the timer motor 16 for the remaining fifty seconds.
Contact 28 of the electromechanical timer 14 is normally closed, and contact 32 is normally open. Accordingly, power is usually supplied to the primary timer motor 16 through contacts 28 during normal cycles of operation of the machine. However, during a time-extension mode of operation of a part;cular event of a selected cycle of operation for the machine, contacts 28 will be open in response to movement of cam 26 and contacts 32 will be closed in response to movement of cam 30.
When contacts 28 open, power is removed from the primary timer motor 16 unless it passes through connection 92. When contacts 32 are closed, a signal is provided through connection 90 to the electronic control circuit 60 indicating to the control circuit 60 that the electronic timer 14 is in the time-extended mode of operation. Accordingly, the electronic control circuit 60 activates and deactivates the triacs 100 and 110 to turn the primary timer motor 16 on for ten seconds and off for fifty seconds during each minute of operation of the time-extended event. By intermittently activating and deactivating the primary time~ motor 16, the time required for movement of cams 38 is increased to extend the overall time of a partlcular event within the selected cycle of operation for the machine. Once the time-extended event has been completed, cams 26, 30 will have been moved to positions whereby electrical contacts 28 are again closed and contacts 32 are again opened. According1y, the input signal to the electronic control '~ - -8-113f~Y39 circuit 60 is removed, thereby ;nd;cat;ng to the control circuit 60 that the electromechanical timer 19 is no 10nger in the time-extended mode of operation and the primary timer motor 16 is again continuously powered through the closed contacts 28.
Referring no~J to Fig. 2, one embodiment of the electronic control circuit 60 is illustrated. The primary controlliny element of the control circuit 60 is a control logic 120 which in the embodiment illustrated is a one-chip microcomputer of the typé MM75 manufactured by Rockwell International Corporation. Althouyh not specifically shown, those skilled in the art will appreciate that the control logic 120 includes a program memory, commonly called a Read Only Memory (ROM), which provides means for storing instructions and constants required to operate the microcomputer. Further, the control logic 120 includes a program counter for addressing the program memory (ROM). Under the ;
control of the program counter, the program memory will read out <
addressed instructions which are to be decoded and executed by the control logic 120. Also included within the control log,ic 120 is a data memory, commonly referred to as a Random Access Memory ~RAM) for storing various data to be used in conjunction with the lnstructions stored within the program memory. The MM75 microcomputer includes a number of terminals which may be connectéd to external circuitry.
For purposes of describing the control circuit 60, some of these terminals have been identified in Fig. 2. For example, terminals Pl-P6 are input ports, terminals Rl-R7 are input/output ports, terminals DO-D8 are discrete input/output ports, terminals INTO and INTl represent conditional interrupt inputs to detect external signals, VSS represents ground (0 volts), and VDD represents the power supply for the microcomputer (l5 volts).
The control logic 120 is coupled to the AC power supply (120 volts) by AC lines Ll, L2 through a 50/60 HZ. clock 122 and a power-initializing g .:, , - - ~.
~L~3~739 or power-up circuit 124. The 50/60 HZ. c1Ock 122 may ;nclude any conventional circuitry for produ~ing a series of oscillations which have a frequency of between 50 and 60 HZ. An output of the 50/60 HZ.
clock 122 is connected to the input terminal INT0 of the control logic 120.
The VC input of the control logic 120 is connected to the VDD
supply voltage through a resistpr 125. The resistor 125 determines the frequency of oscillation o~ the internal clock of the control logic 120.
The P0 input of the control logic 120 ;s connected to the power-up circuit 124. The power-up circuit 124 maintains the voltage at the P0 input near VSS until the VDD supply voltage reaches its final value during initialization of the circuit 60. Accordingly, the power-up circuit 124 assures that the control logic 120 will start at a fixed location each time the circuit 60 is initialized.
The AC lines Ll, L2 are also connected to a regulated DC power supply 126 to-provide a DC voltage to the control circuit 60. The regulated DC power supply 126 includes a resistor, diode, capacitor and zener diodes arranged in a conventional manner to supply~half-wave rectified positive and negative DC voltages. The control logic 120 and the display 128 require a positive 15 volts and 24 volts, respectively. In addition, the control circuit 60 and the display 128 require a negative 5.6 volts.
Connected to various outputs D0-D3 and Rl-R7 of the control logic 120 is a display circuit 128 for displaying the time remaining in a selected delay time period before activation of the electromechanical timer 14. The d;splay c;rcu;t 128 inc1udes a convent;onal vacuum fluorescent display 130 ;nc1ud;ny numer;cal d;g;~s 132, 134, 136 for displaying the t;me remaining in hours and m;nutes and a d;g;t 138 forming a colon separating the hour numerlcal digit 132 from the minutes numerical digits 134, 136. Each numerical digit 132, 134, and .~j ' -1 0-... , . . .... ... .. _, 735~
136 includes seven segments Sl-S7 which are respectively connected to the outputs Rl-R7 of the control logic 120. Each of the numerical digits 132, 13~, and 136 and the colon digit 138 are also connected to the DC power supply line (+V) through res;stors 148, 150, 152, 154, respectively. The inputs 140, 142, 144 and 146 provide the necessary signal to drive each of the numerical digits and the colon digit.
The outputs Rl-R7 of the control logic 120 supply the necessary signals to the various segments Sl-57 of each numerical digit 132, 1341 136 to display an appropriate number. Also associated with the vacuum fluorescent display 130 is a display filament 156 interconnected between the AC lines Ll, L2. In the normal operation of the vacuum fluorescent display, 2.4 volts AC is applied across the 10 display filament 156. A resistor 158 coupling the vacuum fluorescent display 130 to the VSS ground establishes a ground reference for the display 130. A series of resistors 160, 162, 164, 166, 168, 170, 172 are interconnected between each of the segment drive lines connecting the -outputs Rl-R7 and the segments Sl-S7, and the AC line L2 or the power supply line (+V) to provide a reference for the outputs Rl-R7 of the ~-control logic 120.
Further included within the electronic control circuit 60 is a ; test circuit 180. The test circu;t 180 includes a first set of terminals 182 for testing the display circuit 128. In response to a - test input at terminals 182, the display 130 may bé advanced at a rate six minutes (on the display) per second to test its operation. A
second set of terminals 184 provide means for testing the program of the control logic 120 by stepping throuyh the program at a speed of one minute per second. The test inputs 182, 184 are respectively connected to the control logic 120 inputs INTl and P3.
A diode 186 may be optionally included w;thin the control circuit 60 to cause the control circuit 60 to operate in response to a 50 , ~ , ~L36739 hertz (HZ.) AC supply voltage. If the diode 186 is removed from the con-trol circuit 60, the circuit 60 will operate in résponse to a 60 hertz (HZ.) AC signal.
Interconnected to the control logic 120 inputs P2, P3, P4, and INTl and the AC line L2 are a series of pull-up resistors 190, 192, 194, 196. Also interconnected to the inputs P2, P3, P4 and INTl and the AC line L2 are a series of capacitors 198, 200, 202 and 204 which have one side connected to ground to attenuate spurious signals which might appear in such inputs. Resistors 206, 208 connected to control logic 120 inputs D5, D6 service to pu11 such inputs D5, D6 to ground potential.
Referring now to Figs. 1 and 2, a time-delay and rapid-advance circuit 210 includes the bi-directional switching device 80 which, as - previously described, is connected to one side of the solenoid 78 of the relay 72 through a connection 88. One main terminal 82 is coupled to the connection 88 and the other main terminal 84 is connected to the AC line L2. The gate 86 of the triac 80 is connected through a bi-polar switching device 212 and a bias resistor 214 to an output D4 of the control logic 120. In one embodiment, the bi-polar-switching device 212 is an NPN transistor having its collector C connected to the gate 86 of the triac 80, its base B connected through bias resistor 214 to the output D4 of the control logic 120 and through a combination of resistors 216, 218 and a capacitor 220 to the power supply line (+V). The emitter E of the transistor 212 is likewise connected to the resistors 216, 21a and capacitor 220. Resistors 216, 218 and capacitor 220 serve to filter and attenuate any noise s;gnals wlthln the circuit 210. A pull-up resistor 222 is interconnected between the collector C of transistor 212, gate 86 of triac 80 and the AC line L2.
A snubber network consisting of res~stor 224 and capacitor 226 connected in parallel with the triac 80 assure the proper activation and deactivatlon of the triac 80.
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, ................. . .
--l 2--3g A conventional clampin~ circuit 230 is connec~ed through connection 90 to a pair of conta-cts 32 of the e1ectromechanical t1mer 14 (see Fig.l) and supplies a time-extension signa1 from the electro-mechanical timer 14 to input D8 of the control logic 120 to ind;cate to the control logic 120 that the electromechanical timer 14 has entered a time-extension mode of operat;on. The clamp;ng c;rcu;t 230 ;s connected to the DC power supply line (~V) and includes a voltage divider network consisting of resistors 232, Z34 and a blocking diode 236 having its anode connected to the connection 90 and its cathode connected to the voltage divider network. Also included in the clamping circuit 230, and interconnected in a conventional manner, are a second diode 238 havilng its anode connected to ground and its cathode connected to the input D8 of control logic 120 and a capac;tor 240. Capacitor 240 has another side connected to the DC power supply line (+V). In general, the clamping circuit 230 converts the AC signal received from the electromechanical timer 14 to a DC or digital signal which can be employed as an input to the control logic 120 to indicate that the electromechanical timer l4 has entered a time-extension mode of operation.
- 20 Control circuit 60 also includes a time-extension motor control circuit 250 for intermittently activating and deactivating the primary timer motor 16 of the electromechanical timer 14 during a time-extension mode of operation of the electromechanical timer 14. The time-extension motor control circuit 250 includes the triacs lO0, llO
which have previously been descr;bed (see Fig. l). Triac lO0 has a main terminal 102 connected to the po~Jer line 42 of the electromechanical time 14 through a connect;on 92 and a main term;nal 104 connected to the primary t;mer motor 16 of the electromechan;cal t;mer 14 through a connect;on 94 The gate 106 of triac 100 is connected through a resistor 118 to a main terminal 112 of triac 110, and the other main terminal 114 oF triac 110 is connected to the AC line L2. The gate 116 of triac 110 is connected through a bi-polar switch;ng dPv;ce 252 and a bias resistor 254 to an output D7 of the control logic lZ0. In one embodiment, the bi-polar switching device 252 is an NPN transistor having its collector C connected to the gate 116 of the triac 110, its base B connected through the bias resistor 254 to the output D7 of the control logic 120 and through a series of resistors 256, 25 and a capacitor 260 to the DC power supply line (~V). The emitter E of the transistor 252 is likewise connected to the resistors 256, 258 and capacitor 260 to attenuate noise and spur;ous signals w;thin the motor control circuit 250. A pull-up resistor 262 is connected to the collector C of transistor 252, the gate ll6 of triac 110, and the AC line L2.
Having provided a detailed description of one embodiment of the present inventiGn, the operation of control system 10 will now be .
discussed in relation to its adaptation to an appliance such as a - dishwasher having a plurality of machine functions 12 and a plurality of cycles of operation which are selectable by the user of the appliance from the selector~switches 50 and which include various events such as drain, wash, fill and heat. The activation and deactivation of the various machine functions 12 during any event of a selected cycle is controlled by an electromechanical timer 14 which includes a primary timer motor 16 and a secondary rapid-advance motor 18. In the operation of the control system 10, a user of the appliance will select a parti-cular cycle of operation by utilizing the selector switches 50. If the user also desires to have the appliance start at a particular time, the time-set switch 64 of the programming means 62 is depressed to program the control logic 120 for a delay of up to nine hours and - fifty minutes. By depressing the time-set switch 64, the second numerical digit 134 from the right of the display 130 will count from 0 to 5 in ~7 .
.
~3S~35~
one second ;ntervals. Once the second digit 134 has reached the numeral 5, it will return to O and the t-hird numerical digit 132 will increase by l until it reaches the numeral 9. When the numerical digit l32 reaches the numeral 9, it will also return to O and the sequence is again repeated. Accordingly, the user is able to program the control logic 120 for a delay of the start of the appliance from zero to nine hours and fifty minutes. Once the appropriate delay time period has been programmed into the control logic 120, the user will depress the start switch 66 and the control logic l20 will begin to count down the time remaining, in one minute intervals, before the appliance will be started. Coincidentally with the depression of the start switch 66, the relay 72 is energized and power is removed from the primary timer motor l6 and the machine functions l2. The energizing of the relay 72 is accomplished by the time-delay and rapid-advance circuit 210 in response to output D4 of the control logic l20. If contacts 24 of the electromechanical timer l4 are closed, the-rapid-advance motor 18 is activated to place the timer in its start position, and once this is accomplished, the contacts 24 will open so that the electromechanical timer 14 is now set to begin the selected cycle of operation of the appliance.
Once the control logic 120 has counted down the programmed time-delay period and therefore the display 130 shows no time remaining, the relay 72 is de-energized by circuit 210 and power is restored to the electromechanical timer 14. Since the primary timer motor l6 has been positioned for starting the selected cycle of operation, the contacts 36 will be closed, and therefore power is supplied to the primary timer motor 16 and the machine ~unctions 12 through the cams and electrical conkacts 38, 40, respectively. Accordingly, the electro-mechanical timer 14 activates and deactivates the machine functions 12 in accordance with the selected cycle and the events of such cycle.
. .
~L~ 3t;~3 9 If the user has selected a t;me-extension mode of operat;on for a particular event of a selected-cycle from the se1ector switches 50, when that particular event is ready to be initiated, electrlcal contacts 28 will open, thereby removing power from the primary timer motor 16 and electrical contacts 32 wiil close, thereby provid;ng a t.;me-extens;on input signal to the control logic 120 at input D8 through the clamping - circuit 230. The time-extension input signal indicates to the control logic 120 that the electromechanical timer 14 has entered a time-extension mode of operation. Accordingly, a signal is supplied at output-Di of the control logic 120, and in accordance with preprogrammed instructions within the control logic 120, the primary timer motor 16 is activated for ten-second intervals and deactivated for fifty-second intervals during each minute by the triacs lO0 and llO. The control logic~l20 has been preprogrammed therefore to extend the time period ~associated ~ith a particular event by five times the original time period associated with the event. During the extension mode of operation, the colons 138 of the display 130 will blink off and on to provide a visual indication to the user that the time of~the particular event is being extended.
The operation of the control system 10 can be more particularly described by referring to the series of flow charts illustrated in Figs. 3-8 which functionally show the preprogrammed instructions of the control logic 120. Fig. 3 generally shows the steps of a method of controlling the operation of a machine in accordance with the present invention, whereas Figs. 4-8 illustrate in detail the various steps within the functional blocks of Fig. 3 Referring specifically to Fig. 3, the steps 300 of a method of control~ing a machine in accordance with the apparatus described herein-above includes the steps o~ start 302 wherein power is applied to the control system 10, setting up and initializ-ing the control logic ,, ..... .. , .. ,.. ,_. ,, ,.. ,_ .. ~
1~3~;739 120 or microcomputer 304, stepping through a time routine 306 wherein the internal clock of the control logic 102 is incremented and the display 130 is decremented, stepping through a display routine 308 wherein the display 130 is monitored-and various activities of the machine are controlled in accordance with the time d;splayed, and determining whether the control logic 120 is to enter the time-extender routine 312 or proceed to the keyboard routine 314 by checking for a high or low AC line input in accordance with step 310. If the AC line input is high, then the control logic 120 program enters the time-extender routine 312, and if the AC line input is low, the controllogic 120 program enters the check-keyboard routine 314. In the keyboard routine 314, if the start switch 66 has been depressed, the control logic 120 program returns to the display routine 308, and if thè
- delay time set switch 6~ has been depressed, the control logic l20 pr~gram enters the delayed time-set routine 316. Subsequent to setting the delay time, the control logic 120 program will again return to the display routine 308.
Importantly, it should be understood that the vario~s stages of the program of control logic 120 are controlled by the AC line voltage.
During the first quarter of an AC line cycle, the keyboard routine 314 occurs. During the second quarter of an AC line cycle, the display routine 308 occurs. During the third quarter of an AC line cycle, the time routine 306 occurs, and during the fourth quarter of an AC
line cycle, the display routine 308 again occurs. Accordingly, the time routine 306 can occur only once during each AC line cycle, whereas -the display routine 308 can occur twice during each AC line cycle.
Referring now to Fig. 4, the particular steps associated w~th the time routine 306 are shown ~n detail. Once the control logic 120 has - been set up and initialized in accordance with step 304, the internal one-minute time counter of the control logic 120 is incremented in ~'J~
, 1~3~ 3~
accordance with step 320, and the control logic 120 checks to determine whether diode 186 is present and whether or not the control system lO is in either one of the test modes o~ operation in accordance with step 32. The one-minute time increment ;s completed in accordance with step 324 and the control logic 120 then determines whether one minute.
has in fact passed in accordance with step. 326. If one minute has elapsed, the next step 328 ;s to determine whether the display 130 is zero, blank, or has some time shown thereon. If there is time shown on the display 130, then the display 130 is decremented by one minute in accordance with step 332 and thereafter enters the display routine 308. If the display 130 is blank, the control logic 120 immediately enters`the display routine 308, and if the display 130 shows zero, the control logic 120 sets itself for the start of the rapid-advance motor 18 in accordance with step 320 and thereafter enters the display routine 308. If one minute has not elapsed, the control logic 120 then determines whether or not the rapid-advance motor 18 has been set to start.
If the rapid-advance motor has been set to start, the control logic 120 determines whether or not one second has elapsed in accordance with step 33, and if it has, then it proceeds to the display routine 308.
If the:rapid-advance motor 18 has not been set to start or if one second has not elapsed, the control logic 120 ;mmediately proceeds to the display routine 308.~ `
The-various steps associated with the display routine 308 are shown in Fig. 5. Where the display routine 308 is entered from steps ; 328, 330, or 332 of the time-routine 306, the first step of the display routine 308 is to set up and initialize the display 130 in accordance . with step 340. Accordingly, the display d~gits 132, 134, 136, 13~
: are illuminated in accordance with the programmed delay time period instep 342. The control logic 120 checks to see ;f the d1splay 130 has 30 timed-out or is at zero ;n step 344, and if the d;splay has not timed-out .
.
k~
&;'739 to zero, it proceeds to determine whether the colon digit is displayed in accordance with step 346. If the colon digit is not displayed, the control logic 120 returns to step 342. If the colon digit is displayed, -the control logic 120 checks to see if it has béen programmed for a delay or a time-extension mode of operation in accordance with steps 348, 350. If the control logic 120 has been programmed for either the delay mode of operation or the time-extension mode of operation, the colons are continuously flashed on and off in accordance with step 356, and the program returns to step 342. If the control logic 120 has not been programmed for either the delay mode of operation or the time-extension mode of operation, the program proceeds to step 310.
If the display l30 has been timed-out, the control logic 120 checks to see if the rapid-advance motor 18 has been set to start in accordance with step 358. If the rapid-advance motor 18 has not been set to start, the program continues to determine whether there is a high or low AC line input in accordance with step 310. If the rapid-advance motor 18 has been set to start, then in accordance with step . -360, start of the rapid-advance motor 18 is initialized.
, Within the control logic 120, the rapid-advance counter is decremented in accordance with step 362 and is continuausly checked in accordance with step 364 to determine when the counter has reached zero. As soon as the rapid-advance counter reaches zero, the delay .
relay 72 is turned~off and the display is blanked in accordance with step 366. As long as the rapid-advance counter has not reached zero, ~ -~
the control logic 120 continues to proceed through the display routine 308 by again starting with step 340. In other words, the display routine 308 continues to make a loop until the control logic 120 determines either that the rapid-advance motor 18 has not been set to start or the control logic 120 has not been programmed for either the delay or time-extension modes of operation, ,~ - ' _19_ ~ ' ' :
~13~3g After completing the display routine 308, the control logic 120 determines whether or not the AC line is high or low to establish whether or not it should enter the time routine 306 or the keyboard routine 314. If the AC line voltage is high, then the control logic proceeds through a time-extender routine 312 to the time routine 306.
Referring particularly to Fig. 6, the various steps of the time-extender routine 312 are shown in detail. Once the control logic 120 has established that the AC line voltage is high, it checks to determine if it is presently in the time-extension mode of operation in accordance 10 with step 370. If the control logic is not presently in the time-extension mode of operation, it then checks, in accordance with step 374, to determine whether it has received a signal at terminal 90 (see Fig. 1), indicating that it should be in the time-extension mode of operation. If the control logic 120 has received a signal at connection gO, it proceeds to turn on the time-extender triac 100 in accordance wlth step 376 and proceed through a series of steps for turning on and turning off the triac to extend the time of a particular event of the machine. If the control logic 120 déterminés that it is presently in the time-extension mode of operation, it checks to determine 20 whether one minute has elapsed in accordance with step 372. If one minute has elapsed, the program proceeds again to step 374. If one mlnute has not elapsed, the program proceeds to step 378 where it determines whether the first ten-second intervals of the present minute have elapsed. It should be noted at this point that, in the time-extender mode of operation, the timer motor 16 is activated by triac 100 for the first ten-second intervals of each minute and is deactivated for the remaining fifty-second intervals of the minute period.
Accordingly, if the tenth-second interval of a minute has not been reached, the program proceeds to the time routlne 306. If the 30 ninth-second interval of the minute has elapsed, the tr;ac 100 is ~ -20-:1~3~739 turned off in accordance with step 380. Thereafter, the program proceeds to.the time routine 306. During step 3~2, if the time-extender output 92 is on, the time-extender triac 100 is also turned off in accordance with step 380.
Referring now to Fig. 7, if the AC line voltage is low, the program proceeds to the keyboard routine 314 wherein the first step of the routine 314 is to wait for a reference point in accordance with step 390. The control logic 120 then assesses the input keys to determine which keys, if any, have been pressed in accordance with step 392. If no keys have been pressed, the program clears the keyboard 62 in accordance with step 394 and proceeds to the display routine ; 308. If an input key has been pressed, it is determined, in step 396, whether or not this is the first time that such key has been depressed.
~f it is not the first time they key has been depressed, the program proceeds to.the display routine 308; however, if it is the first time the key has been depressed, the control logic 120 then determines ~
whether or not the start switch 66 or the time-set delay switch 64 of :
the keyboard 62 has been depressed in accordance with stép 398. If the start switch 66 has been depressed, the program proceeds to the display routine 308, and if the delay time-set switch 64 has been depressed, the program proceeds to the delay time-set routine 316.
The various steps associated with the delay time-set routine 316 ; . are shown in detail in Fig. 8. The first step of the delay time-set routine 316 is to determine whether or not the display 130 is blank in accordance with step 400. If the display 130 is blank, the control logic 120 loads the display in accordance with step 402. If the d~splay is not blank, the control logic clears the one's of minutes digit 136 ` of the display in acordance ~Jith step 404. The control logic 120 then procéeds to determine whéther the ten's of minutes or hours are being programmed by the user. This determination is made in step 406.
` ` ~' , ', '.
. . .
. ~ . . .
~3~73~
If the ten's of minutes d;git 134 of the d;splay 130 is being pro-grammed, then -the hours digit 1~2 of the display 130 ;s activated in accordance with step 410. In step 412, either the ten's of minutes digit 134 or the hours d;g;t 132 are incremented while the operator is depressing the time-set switch 64. In step 414, the control logic 120 determines whether the ten's of minutes display digit 134 equals six. If the ten's of minutes digit 134 equals siY~, the control logic 120 proceeds to set the display digit 132 for programming hours in ` accordance with step 416. Subsequently, the ten's of m;nutes dlg;t 134 is clear and the hours d;git 132 is incremented from zero to nine.
In step 420, the selected delay time ;s then set w;th;n the program and on the display 130. If in step 414 the-ten's of m;nutes d;git 134 does not equal six, the program proceeds to step 420 where the selected delay time is set. Once the delay time has been set, the delay relay 72 (see Fig. 1) is turned on in accordance with step 422 and the control logic 120 proceeds to the display routine 308. As previously described, the display routine 308 continuously checks to determine whether the display 130 has completely timed-out and therefore the delay period has ended and de-energizes the delay relay -20 72 to start the operation of the electromechanical timer 14.
~. -22-
electromechanical timer in conjunction with an electronic contro1 circuit which employs a microprocessor. In general, the electronic control circuit allows the operator of the machine to program a delay up to nine hours and fifty minutes before the electromechanical timer and the machine are activated. Furthermore, the electronic control circuit includes provisions for extending the time of a particular event of a cycle of operation of the machine upon receipt of a signal from the electromechanical t;mer that the mach;ne ;s ;n a tlme-extension mode of operation. ~-Referring in particular now to Fig. l, the control system lO of the present invention ;s d;agrammatically illustrated to show the relationship between the electromechanical timer and the electronic control circuit. While the control system lO will be described hereinafter with respect to its adaptation to an appliance such as a dishwasher, it will be understood by those skilled in the art that the control system lO could also be adapted to control other machines havlng a plurality of machine functions 12 which are activated and dèactivated in accordance with selected cycles of operation of the mach;ne. In an appliance such as a dishwasher, the machine functions 12 typically include motors, pumps, heaters, and relays. However, it is unimportant to the system lO of the present invention what functions are associated with the machine being controlled.
Many appliances are presently controlled by electromechanical timers or control devices l4 which, in accordance with cycle selection by the operation of the appl;ance, activate and deactivate the var;ous funct;ons associated with the dishwasher in predetermined sequences ; of timed events. For example, an electromechan;cal t;mer or control device 14 may be of the type M-520 manufactured by Mallory Components Group, Emhart Industries, Inc, Associated with these convent-ional electromechanical timers 14 is a main or timer motor (TM) 16, ~L3~ 3~
and in the M-520, a secondary or rapid-advance motor (RAM~ 18. Where a timer motor 16 and a rapid-ad~ance motor 18 are included in an electromechanical timer 14, a clutch 20 is included to engage and disengage the motors 16, 18 so that they are operable independently of each other. Each of the motors 16, 18 are mechanically connected to and, therefore, drive a plurality of disks or cams Z2, 26, 30, 34 and 38. Each of these cams has one or more cam surfaces (not shown) which open and close electrical contacts 24, 28, 32, 36 and 40, respecti-vely, as one of the motors 16, 18 rotates the circular cams 22, 26, 30, 34 and 38 to move the cam surfaces. A plurality of these cams 22, 26, 30, 34 and 38 are commonly referred to by those skilled in the art as a cam stack within the electromechanical timer 14. The electro-mechanical timer 14 also includes an internal power line 42 which is connected to one side of one or more of the electrical contacts associated with the various cams. Furthermore, a selector switch ` panel 50 is provided external to the appl;ance and includes a plurality of switches which allow the user of the appliance to select various optional cycles of operation for the appliance.
In operation, power is supplied to the electromechanical timer 14 through electrical contacts 36 of one or more cams 34 and the selector switches 50. Accordingly, when electrical contacts 36 are closed, electrical power is supplied through selector switches 50 to the power line 42 within the electromechanical timer 14, the timer motor 16, and a series of cams 38 and electrical contacts 40 to control the activation and deactivation of the machine functions 12. It should be noted that various numbers of cams 38 and associated contacts ~0 may be provlded within the conventional timer 14 to control the operation o~ the appliance or machine.
Continuing to refer to Fig. 1, an electron~c control circuit 60 for controlling the activation and deactivatlon of the electromechanical : . . . . .
~13~
timer 14 includes means 62 for programming the electronic circuit 60, The programming means 62 includes a switch 64 ~or sett;ng a delay time or time of day when the electromechanical timer 14 is to be activated and a switch 66 for actuating the control system 10 The operat1On of the programming means 62 will be described in more detail later.
The control system 10 is connected to an AC, 120 volt power supply through lines Ll, L2 and a switch 70. In an appliance, switch 70 may be incorporated into a door so that when the door is closed switch 70 is also closed. The AC lines Ll~ L2 supply AC pawer directly to the electronic control circuit 60 and to a relay 72. Relay 72 includes two contacts 74, 76 and an arm 77 which is movable ~rom one contact to another by a solenoid 78. As illustrated in Fig. 1, the arm 77 of relay 72 normally engages contact 74 when solenoid 78 is not energized. Accordingly, AC line Ll is connected through the switch 70, - relay 72, and contacts 36 to the electromechanical timer 14 when the relay 72 is not energized. As long as cam 34 is in position such that contacts 36 are closed, power is supplied through the selector switches - 50 to the power line 42 within the electromechan;cal timér 14 and ultimately through cams 38 and switches 40 to the machine functions 12.
The electronic control circuit 60 also includes a bi-directional switching devic~ 80, such as a triac, having main terminals 82, 84 and a gate 86. Main terminal 82 of the triac 80 is connected through a connector 88 to the solenoid 78 of the relay 72 and main terminal 84 is connected to the AC line L2. As will be described in more detail later, when the electronic control circuit 60 has been programmed to delay the start of the electromechanical t;mer 14, triac 80 is activated and solenoid 78 ;s energized so that the arm 77 engages contact 76.
When arm 77 engages contact 76, the AC line Ll is connected through the switch 70 and the rela~ 72 to the contacts 25 of electromechanical timer 14. If the cam 22 associated with contacts 24 is in such a position , ~ -6-__. , .. ,.. , ... __ ,_ ~ , . .... .
, ~L13~739 that contacts 24 are closed, as illustrated, the secondary or rapid-advance motor 18 is activated to rotate the cams Z2, 26, 3a, 34 and 38 until contacts 24 are opened by cam 22, at which time the rapid-advance motor 18 is deactivated. When contacts 24 are openéd, the electro-mechanical timer 14 should be set in its start position. Accordinyly, it will be understood that if contacts 24 are opened when solenoid 78 is energized and arm 77 engages contact 76, the rapid-advance motor 18 will remain deactivated since the electrornechanical timer 14 is already in its start position. Importantly, when the arm 77 of relay 72 engages contact 76, power is removed from contacts 36 of the electromechanical timer 14 so that power is removed from the primary timer motor 16 and the machine functions 12. It can, therefore, be appreciated that if the rapid-advance motor 18 is activated through contacts 24 and the cams 22, 26, 30, 34 and 3~ are moved to set the electromechanical timer 14 in its start position, the machine functions 12 and the primary timer motor 16 will not be activated, even though some contacts and -- switches o~ the electromechanical timer may be closed, because power will have been removed from the contacts 36 by the relay 72.
The electronic control circuit 60 is also electrically connected to the electromechanical timer 14 through connections 90, 92 and 94 in the following manner. The electronic control circuit 60 includes ~-~
another bi-direc-tional switching device or triac 100 having main terminals 102, 104 and a gate 106. Main terminal 102 of the triac 100 is connected to the power line 42 within the electromechanical timer 14 through connection 92, and ma;n terminal 104 of triac 100 is connected to one side of the primary timer motor 16 throuyh connectlon 94. The gate 106 of triac 100 is connected to another bi-directional switching device or triac llO o~ the electronic control circuit 60. Triac 110 includes main terminals 112, 114 and a gate 116. Main terminal 112 of the triac 110 is connected to the gate 106 of triac 100 through ~ -7-.
113~'739 resistor 118 and main terminal 114 of triac 110 is connected to the AC
line L2. In the operation of control system 10, triacs 110, 110 intermittently activate and deactivate the primary timer motor 16 when a cycle has been selected from selector switches 50 which includes a time-extended-event. In one embod;ment of the control system 10, the electronic control circuit 60 is preprogrammed to activate the timer motor 16 for ten seconds of each minute of the time-extended event and deactivates the timer motor 16 for the remaining fifty seconds.
Contact 28 of the electromechanical timer 14 is normally closed, and contact 32 is normally open. Accordingly, power is usually supplied to the primary timer motor 16 through contacts 28 during normal cycles of operation of the machine. However, during a time-extension mode of operation of a part;cular event of a selected cycle of operation for the machine, contacts 28 will be open in response to movement of cam 26 and contacts 32 will be closed in response to movement of cam 30.
When contacts 28 open, power is removed from the primary timer motor 16 unless it passes through connection 92. When contacts 32 are closed, a signal is provided through connection 90 to the electronic control circuit 60 indicating to the control circuit 60 that the electronic timer 14 is in the time-extended mode of operation. Accordingly, the electronic control circuit 60 activates and deactivates the triacs 100 and 110 to turn the primary timer motor 16 on for ten seconds and off for fifty seconds during each minute of operation of the time-extended event. By intermittently activating and deactivating the primary time~ motor 16, the time required for movement of cams 38 is increased to extend the overall time of a partlcular event within the selected cycle of operation for the machine. Once the time-extended event has been completed, cams 26, 30 will have been moved to positions whereby electrical contacts 28 are again closed and contacts 32 are again opened. According1y, the input signal to the electronic control '~ - -8-113f~Y39 circuit 60 is removed, thereby ;nd;cat;ng to the control circuit 60 that the electromechanical timer 19 is no 10nger in the time-extended mode of operation and the primary timer motor 16 is again continuously powered through the closed contacts 28.
Referring no~J to Fig. 2, one embodiment of the electronic control circuit 60 is illustrated. The primary controlliny element of the control circuit 60 is a control logic 120 which in the embodiment illustrated is a one-chip microcomputer of the typé MM75 manufactured by Rockwell International Corporation. Althouyh not specifically shown, those skilled in the art will appreciate that the control logic 120 includes a program memory, commonly called a Read Only Memory (ROM), which provides means for storing instructions and constants required to operate the microcomputer. Further, the control logic 120 includes a program counter for addressing the program memory (ROM). Under the ;
control of the program counter, the program memory will read out <
addressed instructions which are to be decoded and executed by the control logic 120. Also included within the control log,ic 120 is a data memory, commonly referred to as a Random Access Memory ~RAM) for storing various data to be used in conjunction with the lnstructions stored within the program memory. The MM75 microcomputer includes a number of terminals which may be connectéd to external circuitry.
For purposes of describing the control circuit 60, some of these terminals have been identified in Fig. 2. For example, terminals Pl-P6 are input ports, terminals Rl-R7 are input/output ports, terminals DO-D8 are discrete input/output ports, terminals INTO and INTl represent conditional interrupt inputs to detect external signals, VSS represents ground (0 volts), and VDD represents the power supply for the microcomputer (l5 volts).
The control logic 120 is coupled to the AC power supply (120 volts) by AC lines Ll, L2 through a 50/60 HZ. clock 122 and a power-initializing g .:, , - - ~.
~L~3~739 or power-up circuit 124. The 50/60 HZ. c1Ock 122 may ;nclude any conventional circuitry for produ~ing a series of oscillations which have a frequency of between 50 and 60 HZ. An output of the 50/60 HZ.
clock 122 is connected to the input terminal INT0 of the control logic 120.
The VC input of the control logic 120 is connected to the VDD
supply voltage through a resistpr 125. The resistor 125 determines the frequency of oscillation o~ the internal clock of the control logic 120.
The P0 input of the control logic 120 ;s connected to the power-up circuit 124. The power-up circuit 124 maintains the voltage at the P0 input near VSS until the VDD supply voltage reaches its final value during initialization of the circuit 60. Accordingly, the power-up circuit 124 assures that the control logic 120 will start at a fixed location each time the circuit 60 is initialized.
The AC lines Ll, L2 are also connected to a regulated DC power supply 126 to-provide a DC voltage to the control circuit 60. The regulated DC power supply 126 includes a resistor, diode, capacitor and zener diodes arranged in a conventional manner to supply~half-wave rectified positive and negative DC voltages. The control logic 120 and the display 128 require a positive 15 volts and 24 volts, respectively. In addition, the control circuit 60 and the display 128 require a negative 5.6 volts.
Connected to various outputs D0-D3 and Rl-R7 of the control logic 120 is a display circuit 128 for displaying the time remaining in a selected delay time period before activation of the electromechanical timer 14. The d;splay c;rcu;t 128 inc1udes a convent;onal vacuum fluorescent display 130 ;nc1ud;ny numer;cal d;g;~s 132, 134, 136 for displaying the t;me remaining in hours and m;nutes and a d;g;t 138 forming a colon separating the hour numerlcal digit 132 from the minutes numerical digits 134, 136. Each numerical digit 132, 134, and .~j ' -1 0-... , . . .... ... .. _, 735~
136 includes seven segments Sl-S7 which are respectively connected to the outputs Rl-R7 of the control logic 120. Each of the numerical digits 132, 13~, and 136 and the colon digit 138 are also connected to the DC power supply line (+V) through res;stors 148, 150, 152, 154, respectively. The inputs 140, 142, 144 and 146 provide the necessary signal to drive each of the numerical digits and the colon digit.
The outputs Rl-R7 of the control logic 120 supply the necessary signals to the various segments Sl-57 of each numerical digit 132, 1341 136 to display an appropriate number. Also associated with the vacuum fluorescent display 130 is a display filament 156 interconnected between the AC lines Ll, L2. In the normal operation of the vacuum fluorescent display, 2.4 volts AC is applied across the 10 display filament 156. A resistor 158 coupling the vacuum fluorescent display 130 to the VSS ground establishes a ground reference for the display 130. A series of resistors 160, 162, 164, 166, 168, 170, 172 are interconnected between each of the segment drive lines connecting the -outputs Rl-R7 and the segments Sl-S7, and the AC line L2 or the power supply line (+V) to provide a reference for the outputs Rl-R7 of the ~-control logic 120.
Further included within the electronic control circuit 60 is a ; test circuit 180. The test circu;t 180 includes a first set of terminals 182 for testing the display circuit 128. In response to a - test input at terminals 182, the display 130 may bé advanced at a rate six minutes (on the display) per second to test its operation. A
second set of terminals 184 provide means for testing the program of the control logic 120 by stepping throuyh the program at a speed of one minute per second. The test inputs 182, 184 are respectively connected to the control logic 120 inputs INTl and P3.
A diode 186 may be optionally included w;thin the control circuit 60 to cause the control circuit 60 to operate in response to a 50 , ~ , ~L36739 hertz (HZ.) AC supply voltage. If the diode 186 is removed from the con-trol circuit 60, the circuit 60 will operate in résponse to a 60 hertz (HZ.) AC signal.
Interconnected to the control logic 120 inputs P2, P3, P4, and INTl and the AC line L2 are a series of pull-up resistors 190, 192, 194, 196. Also interconnected to the inputs P2, P3, P4 and INTl and the AC line L2 are a series of capacitors 198, 200, 202 and 204 which have one side connected to ground to attenuate spurious signals which might appear in such inputs. Resistors 206, 208 connected to control logic 120 inputs D5, D6 service to pu11 such inputs D5, D6 to ground potential.
Referring now to Figs. 1 and 2, a time-delay and rapid-advance circuit 210 includes the bi-directional switching device 80 which, as - previously described, is connected to one side of the solenoid 78 of the relay 72 through a connection 88. One main terminal 82 is coupled to the connection 88 and the other main terminal 84 is connected to the AC line L2. The gate 86 of the triac 80 is connected through a bi-polar switching device 212 and a bias resistor 214 to an output D4 of the control logic 120. In one embodiment, the bi-polar-switching device 212 is an NPN transistor having its collector C connected to the gate 86 of the triac 80, its base B connected through bias resistor 214 to the output D4 of the control logic 120 and through a combination of resistors 216, 218 and a capacitor 220 to the power supply line (+V). The emitter E of the transistor 212 is likewise connected to the resistors 216, 21a and capacitor 220. Resistors 216, 218 and capacitor 220 serve to filter and attenuate any noise s;gnals wlthln the circuit 210. A pull-up resistor 222 is interconnected between the collector C of transistor 212, gate 86 of triac 80 and the AC line L2.
A snubber network consisting of res~stor 224 and capacitor 226 connected in parallel with the triac 80 assure the proper activation and deactivatlon of the triac 80.
k7 `
, ................. . .
--l 2--3g A conventional clampin~ circuit 230 is connec~ed through connection 90 to a pair of conta-cts 32 of the e1ectromechanical t1mer 14 (see Fig.l) and supplies a time-extension signa1 from the electro-mechanical timer 14 to input D8 of the control logic 120 to ind;cate to the control logic 120 that the electromechanical timer 14 has entered a time-extension mode of operat;on. The clamp;ng c;rcu;t 230 ;s connected to the DC power supply line (~V) and includes a voltage divider network consisting of resistors 232, Z34 and a blocking diode 236 having its anode connected to the connection 90 and its cathode connected to the voltage divider network. Also included in the clamping circuit 230, and interconnected in a conventional manner, are a second diode 238 havilng its anode connected to ground and its cathode connected to the input D8 of control logic 120 and a capac;tor 240. Capacitor 240 has another side connected to the DC power supply line (+V). In general, the clamping circuit 230 converts the AC signal received from the electromechanical timer 14 to a DC or digital signal which can be employed as an input to the control logic 120 to indicate that the electromechanical timer l4 has entered a time-extension mode of operation.
- 20 Control circuit 60 also includes a time-extension motor control circuit 250 for intermittently activating and deactivating the primary timer motor 16 of the electromechanical timer 14 during a time-extension mode of operation of the electromechanical timer 14. The time-extension motor control circuit 250 includes the triacs lO0, llO
which have previously been descr;bed (see Fig. l). Triac lO0 has a main terminal 102 connected to the po~Jer line 42 of the electromechanical time 14 through a connect;on 92 and a main term;nal 104 connected to the primary t;mer motor 16 of the electromechan;cal t;mer 14 through a connect;on 94 The gate 106 of triac 100 is connected through a resistor 118 to a main terminal 112 of triac 110, and the other main terminal 114 oF triac 110 is connected to the AC line L2. The gate 116 of triac 110 is connected through a bi-polar switch;ng dPv;ce 252 and a bias resistor 254 to an output D7 of the control logic lZ0. In one embodiment, the bi-polar switching device 252 is an NPN transistor having its collector C connected to the gate 116 of the triac 110, its base B connected through the bias resistor 254 to the output D7 of the control logic 120 and through a series of resistors 256, 25 and a capacitor 260 to the DC power supply line (~V). The emitter E of the transistor 252 is likewise connected to the resistors 256, 258 and capacitor 260 to attenuate noise and spur;ous signals w;thin the motor control circuit 250. A pull-up resistor 262 is connected to the collector C of transistor 252, the gate ll6 of triac 110, and the AC line L2.
Having provided a detailed description of one embodiment of the present inventiGn, the operation of control system 10 will now be .
discussed in relation to its adaptation to an appliance such as a - dishwasher having a plurality of machine functions 12 and a plurality of cycles of operation which are selectable by the user of the appliance from the selector~switches 50 and which include various events such as drain, wash, fill and heat. The activation and deactivation of the various machine functions 12 during any event of a selected cycle is controlled by an electromechanical timer 14 which includes a primary timer motor 16 and a secondary rapid-advance motor 18. In the operation of the control system 10, a user of the appliance will select a parti-cular cycle of operation by utilizing the selector switches 50. If the user also desires to have the appliance start at a particular time, the time-set switch 64 of the programming means 62 is depressed to program the control logic 120 for a delay of up to nine hours and - fifty minutes. By depressing the time-set switch 64, the second numerical digit 134 from the right of the display 130 will count from 0 to 5 in ~7 .
.
~3S~35~
one second ;ntervals. Once the second digit 134 has reached the numeral 5, it will return to O and the t-hird numerical digit 132 will increase by l until it reaches the numeral 9. When the numerical digit l32 reaches the numeral 9, it will also return to O and the sequence is again repeated. Accordingly, the user is able to program the control logic 120 for a delay of the start of the appliance from zero to nine hours and fifty minutes. Once the appropriate delay time period has been programmed into the control logic 120, the user will depress the start switch 66 and the control logic l20 will begin to count down the time remaining, in one minute intervals, before the appliance will be started. Coincidentally with the depression of the start switch 66, the relay 72 is energized and power is removed from the primary timer motor l6 and the machine functions l2. The energizing of the relay 72 is accomplished by the time-delay and rapid-advance circuit 210 in response to output D4 of the control logic l20. If contacts 24 of the electromechanical timer l4 are closed, the-rapid-advance motor 18 is activated to place the timer in its start position, and once this is accomplished, the contacts 24 will open so that the electromechanical timer 14 is now set to begin the selected cycle of operation of the appliance.
Once the control logic 120 has counted down the programmed time-delay period and therefore the display 130 shows no time remaining, the relay 72 is de-energized by circuit 210 and power is restored to the electromechanical timer 14. Since the primary timer motor l6 has been positioned for starting the selected cycle of operation, the contacts 36 will be closed, and therefore power is supplied to the primary timer motor 16 and the machine ~unctions 12 through the cams and electrical conkacts 38, 40, respectively. Accordingly, the electro-mechanical timer 14 activates and deactivates the machine functions 12 in accordance with the selected cycle and the events of such cycle.
. .
~L~ 3t;~3 9 If the user has selected a t;me-extension mode of operat;on for a particular event of a selected-cycle from the se1ector switches 50, when that particular event is ready to be initiated, electrlcal contacts 28 will open, thereby removing power from the primary timer motor 16 and electrical contacts 32 wiil close, thereby provid;ng a t.;me-extens;on input signal to the control logic 120 at input D8 through the clamping - circuit 230. The time-extension input signal indicates to the control logic 120 that the electromechanical timer 14 has entered a time-extension mode of operation. Accordingly, a signal is supplied at output-Di of the control logic 120, and in accordance with preprogrammed instructions within the control logic 120, the primary timer motor 16 is activated for ten-second intervals and deactivated for fifty-second intervals during each minute by the triacs lO0 and llO. The control logic~l20 has been preprogrammed therefore to extend the time period ~associated ~ith a particular event by five times the original time period associated with the event. During the extension mode of operation, the colons 138 of the display 130 will blink off and on to provide a visual indication to the user that the time of~the particular event is being extended.
The operation of the control system 10 can be more particularly described by referring to the series of flow charts illustrated in Figs. 3-8 which functionally show the preprogrammed instructions of the control logic 120. Fig. 3 generally shows the steps of a method of controlling the operation of a machine in accordance with the present invention, whereas Figs. 4-8 illustrate in detail the various steps within the functional blocks of Fig. 3 Referring specifically to Fig. 3, the steps 300 of a method of control~ing a machine in accordance with the apparatus described herein-above includes the steps o~ start 302 wherein power is applied to the control system 10, setting up and initializ-ing the control logic ,, ..... .. , .. ,.. ,_. ,, ,.. ,_ .. ~
1~3~;739 120 or microcomputer 304, stepping through a time routine 306 wherein the internal clock of the control logic 102 is incremented and the display 130 is decremented, stepping through a display routine 308 wherein the display 130 is monitored-and various activities of the machine are controlled in accordance with the time d;splayed, and determining whether the control logic 120 is to enter the time-extender routine 312 or proceed to the keyboard routine 314 by checking for a high or low AC line input in accordance with step 310. If the AC line input is high, then the control logic 120 program enters the time-extender routine 312, and if the AC line input is low, the controllogic 120 program enters the check-keyboard routine 314. In the keyboard routine 314, if the start switch 66 has been depressed, the control logic 120 program returns to the display routine 308, and if thè
- delay time set switch 6~ has been depressed, the control logic l20 pr~gram enters the delayed time-set routine 316. Subsequent to setting the delay time, the control logic 120 program will again return to the display routine 308.
Importantly, it should be understood that the vario~s stages of the program of control logic 120 are controlled by the AC line voltage.
During the first quarter of an AC line cycle, the keyboard routine 314 occurs. During the second quarter of an AC line cycle, the display routine 308 occurs. During the third quarter of an AC line cycle, the time routine 306 occurs, and during the fourth quarter of an AC
line cycle, the display routine 308 again occurs. Accordingly, the time routine 306 can occur only once during each AC line cycle, whereas -the display routine 308 can occur twice during each AC line cycle.
Referring now to Fig. 4, the particular steps associated w~th the time routine 306 are shown ~n detail. Once the control logic 120 has - been set up and initialized in accordance with step 304, the internal one-minute time counter of the control logic 120 is incremented in ~'J~
, 1~3~ 3~
accordance with step 320, and the control logic 120 checks to determine whether diode 186 is present and whether or not the control system lO is in either one of the test modes o~ operation in accordance with step 32. The one-minute time increment ;s completed in accordance with step 324 and the control logic 120 then determines whether one minute.
has in fact passed in accordance with step. 326. If one minute has elapsed, the next step 328 ;s to determine whether the display 130 is zero, blank, or has some time shown thereon. If there is time shown on the display 130, then the display 130 is decremented by one minute in accordance with step 332 and thereafter enters the display routine 308. If the display 130 is blank, the control logic 120 immediately enters`the display routine 308, and if the display 130 shows zero, the control logic 120 sets itself for the start of the rapid-advance motor 18 in accordance with step 320 and thereafter enters the display routine 308. If one minute has not elapsed, the control logic 120 then determines whether or not the rapid-advance motor 18 has been set to start.
If the rapid-advance motor has been set to start, the control logic 120 determines whether or not one second has elapsed in accordance with step 33, and if it has, then it proceeds to the display routine 308.
If the:rapid-advance motor 18 has not been set to start or if one second has not elapsed, the control logic 120 ;mmediately proceeds to the display routine 308.~ `
The-various steps associated with the display routine 308 are shown in Fig. 5. Where the display routine 308 is entered from steps ; 328, 330, or 332 of the time-routine 306, the first step of the display routine 308 is to set up and initialize the display 130 in accordance . with step 340. Accordingly, the display d~gits 132, 134, 136, 13~
: are illuminated in accordance with the programmed delay time period instep 342. The control logic 120 checks to see ;f the d1splay 130 has 30 timed-out or is at zero ;n step 344, and if the d;splay has not timed-out .
.
k~
&;'739 to zero, it proceeds to determine whether the colon digit is displayed in accordance with step 346. If the colon digit is not displayed, the control logic 120 returns to step 342. If the colon digit is displayed, -the control logic 120 checks to see if it has béen programmed for a delay or a time-extension mode of operation in accordance with steps 348, 350. If the control logic 120 has been programmed for either the delay mode of operation or the time-extension mode of operation, the colons are continuously flashed on and off in accordance with step 356, and the program returns to step 342. If the control logic 120 has not been programmed for either the delay mode of operation or the time-extension mode of operation, the program proceeds to step 310.
If the display l30 has been timed-out, the control logic 120 checks to see if the rapid-advance motor 18 has been set to start in accordance with step 358. If the rapid-advance motor 18 has not been set to start, the program continues to determine whether there is a high or low AC line input in accordance with step 310. If the rapid-advance motor 18 has been set to start, then in accordance with step . -360, start of the rapid-advance motor 18 is initialized.
, Within the control logic 120, the rapid-advance counter is decremented in accordance with step 362 and is continuausly checked in accordance with step 364 to determine when the counter has reached zero. As soon as the rapid-advance counter reaches zero, the delay .
relay 72 is turned~off and the display is blanked in accordance with step 366. As long as the rapid-advance counter has not reached zero, ~ -~
the control logic 120 continues to proceed through the display routine 308 by again starting with step 340. In other words, the display routine 308 continues to make a loop until the control logic 120 determines either that the rapid-advance motor 18 has not been set to start or the control logic 120 has not been programmed for either the delay or time-extension modes of operation, ,~ - ' _19_ ~ ' ' :
~13~3g After completing the display routine 308, the control logic 120 determines whether or not the AC line is high or low to establish whether or not it should enter the time routine 306 or the keyboard routine 314. If the AC line voltage is high, then the control logic proceeds through a time-extender routine 312 to the time routine 306.
Referring particularly to Fig. 6, the various steps of the time-extender routine 312 are shown in detail. Once the control logic 120 has established that the AC line voltage is high, it checks to determine if it is presently in the time-extension mode of operation in accordance 10 with step 370. If the control logic is not presently in the time-extension mode of operation, it then checks, in accordance with step 374, to determine whether it has received a signal at terminal 90 (see Fig. 1), indicating that it should be in the time-extension mode of operation. If the control logic 120 has received a signal at connection gO, it proceeds to turn on the time-extender triac 100 in accordance wlth step 376 and proceed through a series of steps for turning on and turning off the triac to extend the time of a particular event of the machine. If the control logic 120 déterminés that it is presently in the time-extension mode of operation, it checks to determine 20 whether one minute has elapsed in accordance with step 372. If one minute has elapsed, the program proceeds again to step 374. If one mlnute has not elapsed, the program proceeds to step 378 where it determines whether the first ten-second intervals of the present minute have elapsed. It should be noted at this point that, in the time-extender mode of operation, the timer motor 16 is activated by triac 100 for the first ten-second intervals of each minute and is deactivated for the remaining fifty-second intervals of the minute period.
Accordingly, if the tenth-second interval of a minute has not been reached, the program proceeds to the time routlne 306. If the 30 ninth-second interval of the minute has elapsed, the tr;ac 100 is ~ -20-:1~3~739 turned off in accordance with step 380. Thereafter, the program proceeds to.the time routine 306. During step 3~2, if the time-extender output 92 is on, the time-extender triac 100 is also turned off in accordance with step 380.
Referring now to Fig. 7, if the AC line voltage is low, the program proceeds to the keyboard routine 314 wherein the first step of the routine 314 is to wait for a reference point in accordance with step 390. The control logic 120 then assesses the input keys to determine which keys, if any, have been pressed in accordance with step 392. If no keys have been pressed, the program clears the keyboard 62 in accordance with step 394 and proceeds to the display routine ; 308. If an input key has been pressed, it is determined, in step 396, whether or not this is the first time that such key has been depressed.
~f it is not the first time they key has been depressed, the program proceeds to.the display routine 308; however, if it is the first time the key has been depressed, the control logic 120 then determines ~
whether or not the start switch 66 or the time-set delay switch 64 of :
the keyboard 62 has been depressed in accordance with stép 398. If the start switch 66 has been depressed, the program proceeds to the display routine 308, and if the delay time-set switch 64 has been depressed, the program proceeds to the delay time-set routine 316.
The various steps associated with the delay time-set routine 316 ; . are shown in detail in Fig. 8. The first step of the delay time-set routine 316 is to determine whether or not the display 130 is blank in accordance with step 400. If the display 130 is blank, the control logic 120 loads the display in accordance with step 402. If the d~splay is not blank, the control logic clears the one's of minutes digit 136 ` of the display in acordance ~Jith step 404. The control logic 120 then procéeds to determine whéther the ten's of minutes or hours are being programmed by the user. This determination is made in step 406.
` ` ~' , ', '.
. . .
. ~ . . .
~3~73~
If the ten's of minutes d;git 134 of the d;splay 130 is being pro-grammed, then -the hours digit 1~2 of the display 130 ;s activated in accordance with step 410. In step 412, either the ten's of minutes digit 134 or the hours d;g;t 132 are incremented while the operator is depressing the time-set switch 64. In step 414, the control logic 120 determines whether the ten's of minutes display digit 134 equals six. If the ten's of minutes digit 134 equals siY~, the control logic 120 proceeds to set the display digit 132 for programming hours in ` accordance with step 416. Subsequently, the ten's of m;nutes dlg;t 134 is clear and the hours d;git 132 is incremented from zero to nine.
In step 420, the selected delay time ;s then set w;th;n the program and on the display 130. If in step 414 the-ten's of m;nutes d;git 134 does not equal six, the program proceeds to step 420 where the selected delay time is set. Once the delay time has been set, the delay relay 72 (see Fig. 1) is turned on in accordance with step 422 and the control logic 120 proceeds to the display routine 308. As previously described, the display routine 308 continuously checks to determine whether the display 130 has completely timed-out and therefore the delay period has ended and de-energizes the delay relay -20 72 to start the operation of the electromechanical timer 14.
~. -22-
Claims (18)
1. A system for controlling a machine having a plurality of cycles of operation, comprising in combination means for selecting a cycle of operation of the machine, an electromechanical control device for activating and deactivating a plurality of machine functions in a timed sequence of events in accordance with the selected cycle, a programmable electronic control circuit for activating and deactivating the electromechanical device in accordance with programmed instructions, first means for interconnecting at least one output terminal of the electronic control circuit to the electromechanical control device to control the operation of the electromechanical device, second means for interconnecting at least one input terminal of the electronic control circuit to the electromechanical control device to program the electronic control circuit to control the operation of the electromechanical device, and means for programming the control circuit to delay the start of the selected cycle.
2. The control system as recited in claim 1 wherein the electro-mechanical control device includes a primary motor and a secondary motor, a plurality of cam surfaces independently movable by the primary and secondary motors, and a plurality of electrical contacts which are opened and closed by the movement of the cam surfaces.
3. The control system as recited in claim 2 wherein power is supplied to the machine functions and the primary and secondary motors through the electrical contacts and the means for selecting the cycle of operation of the machine.
4. The control system as recited in claim 3 further comprising means for switching the supply of power to the electromechanical timer, and third means for interconnecting at least one output of the electronic control circuit to the power supply switching means.
5. The control system as recited in claim 4 wherein the programming means includes a switching device for entering a delay time period into the electronic control circuit and a switching device for starting the control system.
6. The control system as recited in claim 5, further comprising means for displaying the delay time period and time remaining before the start of the selected cycle
7. The control system as recited in claim 6 wherein the third interconnecting means includes means for activating and deactivating the power supply switching means, the power supply switching means being activated in response to the electronic control circuit to remove power from the machine functions and the primary motor during the delay time period, and the power supply switching means being deactivated in response to the electronic control circuit to apply power to the machine functions and the primary motor at the end of the delay time period.
8. The control system as recited in claim 7, further comprising fourth means interconnecting the power supply switching means to the secondary motor.
9. The control system as recited in claim 8 wherein the fourth interconnecting means includes a first electrical contact of the electro-mechanical control device, the secondary motor being activated when the power switching device is activated and the electrical contacts are closed to set the electromechanical control device in a start position.
10. The control system as recited in claim 9 wherein the second interconnecting means includes a second electrical contact of the electromechanical control device, the second electrical contact when closed indicating to the electronic control circuit a selected mode of operation of the machine.
11. The control system as recited in claim 10 wherein the first interconnecting means includes means for activating and deactivating the primary motor in accordance with programmed instructions of the electronic control circuit.
12. The control system as recited in claim 11 wherein the primary motor is activated for ten seconds of every minute and deactivated for the remaining fifty seconds of every minute.
13. A system for controlling the operation of an electromechanical control device of the type including a motor, a plurality of cams rotated by the motor, and a plurality of electrical contacts which are opened and closed in response to rotation of the cams comprising a control logic unit having means for storing instructions and data and a plurality of input and output terminals, first means interconnecting output terminals of the control logic to the motor of the electro-mechanical control device, the interconnecting means including switching devices for activating and deactivating the motor, means for programming a selected time interval into the control logic to delay the activation of the electromechanical control device, and second means for inter-connecting at least one input terminal of the control logic to at least one electrical contact of the electromechanical control device to control the operation of the motor
14. The control system as recited in claim 13 wherein the first interconnecting means includes a first switching device for removing power from the motor during the selected delay time interval and a second switching device for activating and deactivating the motor in response to an electrical signal provided to the control logic from the electromechanical control device by the second interconnecting means.
15. A system for controlling a machine having a plurality of cycles of operation, comprising means for selecting a cycle of operation of the machine, an electromechanical timer for activating and de-activating a plurality of machine functions in a sequence of timed events determined by the selected cycle; the electromechanical timer including a primary motor, a plurality of cam surfaces which are movable in response to the primary motor, a plurality of electrical contacts which are opened and closed by the cam surfaces, and a secondary motor for advancing the movement of the cam surfaces to vary a time period of an event of a selected cycle of operation of the machine; an electronic control circuit for activating and deactivating the primary and secondary motors of the electromechanical control device; the electronic control circuit including a control logic unit, means for programming the control logic unit to delay the start of a selected cycle, and a plurality of input and output terminals; means for coupling at least one input terminal of the control circuit to the means for selecting a cycle of operation of the machine, first switching means controlled by a first output terminal of the control circuit for removing power from the primary motor during a programmed time delay; the first switching means interconnecting the primary motor of the electromechanical device and a power supply line; and second switching means controlled by a second output terminal of the control circuit for controlling the operation of the primary motor during a timed event of a selected cycle of operation of the machine.
16. In a machine having means for selecting a plurality of cycles of operation and a plurality of machine functions which are activated and deactivated in a sequence of timed events in accordance with a selected cycle by an electromechanical timer wherein the improvement comprises programmable means for controlling the activation and deactivation of the electromechanical timer having at least one input terminal and at least one output terminal coupled to the electromechanical timer; the means for controlling the electromechanical timer including means for selectively programming a time of day when the electromechanical timer is to be activated and the selected cycle of operation started, and further including a preprogrammed set of instructions for periodi-cally activating and deactivating the electromechanical timer to expand the timer period of at least one of the events in response to selection of a predetermined cycle of operation.
17. A method of controlling a machine having a plurality of machine functions and cycles of operation, comprising the steps of removing power from the machine functions and a main motor of an electromechanical timer, applying power to a secondary motor of the electromechanical timer to return the timer to its start position, counting down a selected time period, and at the end of the selected time period removing power from the secondary motor of the timer and applying power to the machine functions and the main motor of the timer to start a selected cycle of operation of the machine.
18. A method of controlling a machine having a plurality of machine functions and cycles of operation which are controlled by an electromechanical timer, comprising the steps of displaying a selected delay time period before activating the electromechanical timer, setting the electromechanical timer in a start position for operation of the machine in accordance with a selected cycle, decrementing the displayed delay time period, activating the electromechanical timer when the delay time period has been decremented to zero, monitoring the electromechanical timer for a signal indicating a mode of operation of the machine, and controlling the operation of the electromechanical timer if the indicating signal is present.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US11580480A | 1980-01-28 | 1980-01-28 | |
| US06/115,804 | 1980-01-28 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1136739A true CA1136739A (en) | 1982-11-30 |
Family
ID=22363483
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000358428A Expired CA1136739A (en) | 1980-01-28 | 1980-08-18 | Control system for a machine |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1136739A (en) |
-
1980
- 1980-08-18 CA CA000358428A patent/CA1136739A/en not_active Expired
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