US005934554A
`5,934,554
`(11) Patent Number:
`115
`United States Patent
`Charlesetal.
`[45] Date of Patent:
`Aug. 10, 1999
`
`
`
`
`
`
`[54] ROOM TEMPERATURE SENSOR AND
`THERMOSTAT CONTROL DEVICE
`
`[75]
`
`Inventors: Donald E. Charles, Wauconda;
`Christopher Wojtowicz, Mt. Prospect;
`Kenneth F. Wolfinger, Skokie, all of
`.
`?
`,
`Tl.
`.
`—_
`.
`.
`
`
`Assignee: Siemens Building Technologies, Inc.,
`
`
`Buttalo Grove,IIL.
`
`Appl. No.: 09/119,924
`Filed:
`Jul. 21, 1998
`Related U.S. Application Data
`
`73]
`
`21]
`22]
`
`62]
`
`Division ofapplication No. 08/684,551, Jul. 19, 1996, Pat.
`No. 5,816,492.
`+
`51)
`Unt. C1eee F24F 3/00; GOSD 23/00
`$2] US. Che we ... 236/46 R; 236/51; 165/209
`58]
`Field of Search
`... 236/46 R, 51,
`
`236/47; 165/209
`
`56
`
`.
`References Cited
`U.S. PATENT DOCUMENTS
`
`3,043,517
`7/1962 Hanna....
`. 236/46 R
`
`3,351,280
`11/1967 Harris .
`236/46 R
`
`4,314,666
`2/1982 Schotten .
`236/78 D
`
`4,379,520
`4/1983 ‘Tomsu....
`236/94 X
`4,395,139
`. 374/183 X
`7/1983 Namiki et al.
`
`4,406,550
`» 374/110
`9/1983 Gray ........
`
`4,455,096
`....
`. 374/170
`6/1984 Brandstedt
`4,466,749
`8/1984 Cunninghamet al.
`............. 374/134
`4,471,354
`9/1984 Smith... ecceseeseeeeeeeeeee 128/631 X
`4,475,685
`ww. 236/46 R
`10/1984 Grimadoetal.
`
`4,480,312 10/1984 Wingate ....ccesecssereeeeeres 374/170 X
`
`5
`
`
`
`3/1985 Johnsonet al. ws. 374/170 X
`4,504,922
`3/1985 Suzuki et al.
`.
`374/170 X
`4,505,600
`
`4,562,554 12/1985 Stixrud et al.
`.. 364/900
`
`4,588,308
`5/1986 Saito .........
`” 374/181
`; 374/103
`4,007,962
`8/1986 Nagao et al.
`
`..
`» 374/163 X
`4,728,199
`3/1988 Murai etal,
`236/94 X&
`4,730,941
`3/1988 Levineetal. .
`
`374/171
`4,838,707
`6/1989 Ozawa etal. .
`
`. 340/449
`4,882,564 11/1989 Monroeetal.
`
`5,085,526
`2/1992 Sawtell elal.
`374/101
`5,116,136
`5/1992
`I
`5,135,045
`8/1992
`5,249,863
`10/1993
`5,495,722
`3/1996 Mansonetal.
`/
`
`5,682,949
`11/1997 Ratcliffe el al.
`.....
`we 236/51 X
`FOREIGN PATENT DOCUMENTS
`1277207
`6/1972 United Kingdom .
`2122390
`1/1984 United Kingdom .
`wae
`,
`.
`Primary Examiner—William Wayner
`Attorney, Agent, or Firm—Greer, Burns & Crain, LLP
`[57]
`ABSTRACT
`A thermostat control having improved user controls wherein
`an analog version contains a binary coded switch for selec-
`tively setting a setpoint
`temperature. The binary coded
`switch is configured to have discrete positions correspond-
`ing to a plurality of setpoint temperaturesettings. It contains,
`among other things, a resistor network configured to pro-
`duce a setpoint signal indicative of the binary coded switch
`position and a setpoint adjust switch for setting the binary
`coded switch position. Also, digital version having a man-
`machine interface port, wherein point information from a
`controller can be viewed and modified with the thermostat
`control device controls when a hardware passkeyis inserted
`into the man-machine interface port.
`
`4 Claims, 10 Drawing Sheets
`
`
`CONTROLLER
`
`HEATING/COOLING
`
`SYSTEM
` DATABASE
`
`12
`
`32
`
`POINT
`
`
`
`
`
`38
`
`poorocecmonntcnreeennncnnnnenncemeneneenencnen+
`
`ROOM
`TEMPERATURE
`SENSOR
`
`
`SETPOINT
`ADJUST
`
`RESISTOR
`NETWORK
`
`
`SWITCH
`
`
`
`18
`MODE
`
`OVERRIDE
`SWITCH
`
`0
`
`MAN MACHINE
`
`INTERFACE
`PORT
`
`:
`
`001
`
`GOOGLE 1015
`GOOGLE 1015
`
`PETITIONER ECOBEE
`EX. 1010
`
`001
`
`PETITIONER ECOBEE
`EX. 1010
`
`

`

`U.S. Patent
`
`Aug. 10, 1999
`
`Sheet 1 of 10
`
`5,934,554
`
`
`
`
`
`CEES,
`
`
`
`oo
`
`
`Y
`
`
`
`Uy
`
`
`
`FIGURE 1
`
`PETITIONER ECOBEE
`EX. 1010
`
`002
`
`PETITIONER ECOBEE
`EX. 1010
`
`

`

`U.S. Patent
`
`5,934,554
`
`Aug. 10, 1999
`
`Sheet 2 of 10
`
`26a
`
`FIGURE 2
`
`003
`
`PETITIONER ECOBEE
`EX. 1010
`
`003
`
`PETITIONER ECOBEE
`EX. 1010
`
`

`

`U.S. Patent
`
`Aug. 10, 1999
`
`Sheet 3 of 10
`
`5,934,554
`
`INITOOD/ONILVSH
`
`WALSAS
`
`ce
`
`YATIOULNOO
`
`LNIOd
`
`asvaviva
`
`9e
`
`¢HANOI
`
`y
`
`SJYNLVYAdWAL
`
`YOSNAS
`
`WOOY
`
`
`
`YOLSISAYINIOdL3aS
`
`Lsnray
`
`SL
`
`Ov
`
`Efete)
`
`AGIYYAAO
`
`HO.LIMS
`
`ANIHOVWNVA
`
`AOVAYSLNI
`
`LYdOd
`
`HILIMS
`
`004
`
`PETITIONER ECOBEE
`EX. 1010
`
`004
`
`PETITIONER ECOBEE
`EX. 1010
`
`
`
`
`
`
`
`
`
`
`
`

`

`U.S. Patent
`
`Aug. 10, 1999
`
`Sheet 4 of 10
`
`5,934,554
`
`TOCONTROLLER
`
`FIGURE4
`
`70
`
`68
`
`66
`
`wT
`co
`
`N
`(o
`
`5658
`
`52
`
`©w
`
`W
`
`CO
`bs
`
`wi
`v
`a|
`5©
`ocre
`Pa
`oO
`O
`
`005
`
`PETITIONER ECOBEE
`EX. 1010
`
`005
`
`PETITIONER ECOBEE
`EX. 1010
`
`

`

`U.S. Patent
`
`Aug. 10, 1999
`
`Sheet 5 of 10
`
`5,934,554
`
`CORRESPONDINGTODEGREESF FIGURE5
`
`
`
`SETPOINTPOSITION
`
`95DEGREESF
`
`65
`
`60 55
`7075808590
`
`Lu
`OQ
`
`=<p
`
`a2“
`
`)
`ud
`ce
`
`006
`
`PETITIONER ECOBEE
`EX. 1010
`
`006
`
`PETITIONER ECOBEE
`EX. 1010
`
`

`

`U.S. Patent
`
`Aug. 10, 1999
`
`Sheet 6 of 10
`
`5,934,554
`
`TOCONTROLLER
`
`FIGURE6
`
`17
`
`—O
`
`oOF
`_
`=<
`oO
`©
`
`007
`
`PETITIONER ECOBEE
`EX. 1010
`
`94
`
`92
`
`3
`
`%
`
`oS
`
`82
`
`80
`
`R
`
`tS
`
`ot
`nN
`
`nN
`hB
`
`007
`
`PETITIONER ECOBEE
`EX. 1010
`
`

`

`U.S. Patent
`
`Aug. 10, 1999
`
`Sheet 7 of 10
`
`5,934,554
`
`80859095POSITIONDEGREESF
`FIGURE7 w)
`
`SETPOINTPOSITION
`
`75
`
`70
`
`©
`
`So
`wo
`
`LO
`ve)
`
`PETITIONER ECOBEE
`EX. 1010
`
`008
`
`Lid
`
`©3
`
`=oh
`
`“~
`Lid
`cf
`
`008
`
`PETITIONER ECOBEE
`EX. 1010
`
`

`

`U.S. Patent
`
`Aug.10, 1999
`
`Sheet 8 of 10
`
`5,934,554
`
`8085
`
`
`
`SETPOINTPOSITION
`
`FIGURE8
`
`eaann
`
`TECINPUTCURRENT
`
`009
`
`PETITIONER ECOBEE
`EX. 1010
`
`009
`
`PETITIONER ECOBEE
`EX. 1010
`
`

`

`U.S. Patent
`
`Aug. 10, 1999
`
`Sheet 9 of 10
`
`5,934,554
`
`
`
`FIGURE 9
`
`PETITIONER ECOBEE
`EX. 101
`
`010
`
`PETITIONER ECOBEE
`EX. 1010
`
`

`

`U.S. Patent
`
`Aug. 10, 1999
`
`Sheet 10 of 10
`
`5,934,554
`
`O€l
`
`SLL
`
`ONIIOOO/DNILVAH
`
`YATIOHULNOD
`
`W3LSAS
`
`INIOd
`
`Asvaviva
`
`961
`
`!801
`
`‘pOR'ZOL
`
`901
`
`Oz1
`
`SUNLVHAdWAL
`
`HOSNAS
`
`WOOH
`
`aot
`
`HOSSADONdOHXODIN
`
`STOYULNOD
`
`011
`
`AJqdOW
`
`AGMHYAaAO
`
`HOILIMS
`
`OFCHAO
`
`ANIHOVIA-NVIN vel
`
`QNV30VAYSLNI
`
`LYOdAASSVd
`
`PETITIONER ECOBEE
`EX. 1010
`
`011
`
`PETITIONER ECOBEE
`EX. 1010
`
`
`
`
`
`
`

`

`5,934,554
`
`1
`ROOM TEMPERATURE SENSOR AND
`THERMOSTAT CONTROL DEVICE
`
`This is a division of application Ser. No. 08/684,551,
`filed Jul. 19, 1996, now U.S. Pat. No. 5,816,492.
`
`FIELD OF THE INVENTION
`
`The present invention relates generally to electronic room
`temperature sensors and thermostat control devices. More
`particularly, the present invention relates to room tempcera-
`ture sensors and thermostat control devices having improved
`user controls.
`
`BACKGROUND OF THE INVENTION
`
`Heating, and cooling systems in large office buildings or
`apartment complexes are generally controlled, in individual
`rooms, by room temperature scnsors and thermostat control
`devices. Such thermostat control devices generally include a
`setpoint control device,
`for setting a desired room
`temperature, a room temperature sensor, for sensing the
`actual room temperature, and a communication mechanism
`for sending the setpoint and temperature information to a
`controller for determining the difference between the desired
`and actual room temperature and for sending a controlsignal
`to the central heating and cooling system indicating tem-
`perature adjustment needs.
`From a users perspective, a thermostat control device’s
`main function is setpoint adjustment. Setpoit controls are
`generally regarded as the main interface between the user
`and the device. Therefore, readability and ease of use of the
`setpoint controls are of the utmost importance.
`Setpoint controls include a display device (in one or more
`embodiments), for displaying the current room temperature
`and setpoint, and a set point adjustment control, for adjust-
`ing the setpoint. Traditionally, setpoimt adjustment has been
`accomplished by a controlling device reading either a resis-
`ance or a current which corresponds to a particular setpoint
`emperature.
`Potentiometers have been used for setpoint adjustment
`when the controlling device reads a resistance. However,
`because the resistance is continuously variable in a
`potentiometer,
`repeatability (the specific resistance at a
`particular pointoftravel) is usually poor. Also, the tempera-
`ure coefficient associated with lowcost potentiometers is
`poor adding further inaccuracy.
`Circuits containing transistors, resistors and potentiom-
`eters have been used for setpoint adjustment when the
`controlling device reads a current. A variable resistance
`potentiometer, without any additional circuitry, would result
`in a nonlinear current change as a function of position.
`Therefore, additional active circuitry is required to produce
`a linear current change as a function of position. In addition
`o the limitations of potentiometers, as described above, the
`active circuitry produces additional inaccuracies and cost.
`Display deviccs have progressed from mercury-based
`hermometers and dials to liquid crystal display (LCD)
`devices. Once again, accuracy and ease of use are essential.
`The user must be able to easily read and operate the display
`device in orderfor it to be effective. Even the mostefficient
`
`
`
`
`heating/cooling systems will be ineffective if the user has
`difficulty operating the device properly.
`The heating and cooling systems mentioned above gen-
`erally maintain a database of setpoint and actual tempera-
`ures for the individual roomsat controllers. The database
`values can usually be viewed and manipulated using a
`
`
`
`1s
`
`boan
`
`3o
`
`40
`
`55
`
`6oa
`
`65
`
`2
`central console or maintenance terminal. In this way, a
`technician or building manager can adjust the setpoinis in
`individual rooms from one central location. In addition, the
`maintenance terminals can be used to upload software
`upgrades as well as perform other maintenance functions.
`The maintenance terminal
`is generally connected to the
`controller in some central location which can be difficult to
`gct to.
`Accordingly,it is a gencral object of the present invention
`to provide an improved thermostat control device adapted
`for controlling the temperature in a space whichis accurate
`and easy to use.
`It is another object of the present invention to provide an
`improved setpoint control device which is accurate and easy
`to use.
`
`It is still another object of the present invention to provide
`an improved thermostat control device which can also be
`used as a maintenance terminal for viewing and adjusting
`database points stored at the controller to which the ther-
`mostat control device is attached.
`
`It is a further object of the present invention to provide an
`improved thermostat control device which contains a man-
`machine interface port for connecting a maintenance termi-
`nal to the temperature control system.
`Other features and advantages of the present invention
`will be apparent from the following description taken in
`conjunction with the accompanying, drawings.
`SUMMARYOF THE INVENTION
`
`the present
`In order to achieve the foregoing objects,
`invention provides a thermostat control device with a binary
`coded switch for selectively setting a setpoint temperature.
`The binary coded switch in several embodiments is config-
`ured to have discrete positions corresponding to a plurality
`of setpoint temperature settings. It contains, among other
`things, a resistor network configured to produce a setpoint
`signal indicative of the binary coded switch position. It also
`includes a mechanical wipcr slidcr assembly (a sctpoint
`adjust switch) for setting the binary coded switch position.
`A series resistor network produces a resistance, corre-
`sponding to a binary coded switch position. This is used by
`controlling devices which read setpoint temperatures as a
`functionof resistance. The binary coded switch performsthe
`function of a lincar position dependent variable resistor
`similar to a potentiometer. However, in a preferred embodi-
`menta 6-bit switch is used to provide up to 64 (2°) discrete
`positions with an accuracy limited by the precision of the
`resistors used. Using only six resistors,
`in the resistor
`network, with one percent tolerance would yield 64 one
`percent(or less) discrete resistance values making the resis-
`tance al a particular position, or pointof travel, constant and
`very repeatable.
`The series resistor network consists of six resistors con-
`nected in series. ‘he resistor values are binary weighted
`(multiples of 1, 2, 4, 8, cte.) so as to produce a lincar
`resistance change as a function of switch position. The
`resistors are connected in parallel with mechanical switches,
`eachresistor being connected in parallel to one switch. The
`switches are opened/closed in a binary coded fashion by the
`setpoint adjust switch. When a switch is closed its parallel
`resistance is shunted. When a switch is open its parallel
`resistance is in the series resistor network. An intercept
`resistor is also provided and is connected in series with the
`scrics resistor nctwork to provide an intercept resistance
`when all switches are closed. Therefore, the series resistor
`network produces a resistance setpoint signal indicative of
`the position of the binary coded switch.
`
`012
`
`PETITIONER ECOBEE
`EX. 1010
`
`012
`
`PETITIONER ECOBEE
`EX. 1010
`
`

`

`5,934,554
`
`3
`A parallel resistor network produces a current value
`corresponding to a binary coded switch position, for systems
`in which the controlling device reads the setpoint tempera-
`ture as a function of current. In this case, the binary coded
`switch performs the function of a position dependent current
`sink.
`
`In this embodiment,six resistors are connected inparallel.
`Theresistor values are binary weighted (multiples of 1, 2, 4,
`8, etc.) to produce discrete current values that vary linearly
`as a function of position. The parallel resistor network
`provides an inexpensive means of obtaining up to 64 (2°)
`discrete positions each with an accuracylimited only by the
`precision of the resistors used. Using only six passive
`components (resistors) with one percent tolerance would
`yield 64 one percent (or less) discrete current values that
`vary linearly as a function of position and at a particular
`position, or point of travel, will be constant and very
`repeatable.
`The resistors are connected in series with mechanical
`switches, one switch being connected to each resistor. A
`sctpomt adjust switch is configured to open/close the
`switches in a binary coded fashion. When a switch is closed,
`its series resister is added to the resistor network in parallel.
`In this manner the resistance will vary nonlinearly over the
`range while the current change will be linear. An intercept
`resistor is connected in parallel with the resistor network to
`provide an intercept current when all switches are open.
`Therefore, the parallel resistor network produces a current
`setpoint signal indicative of the binary coded switch posi-
`tion.
`
`The thermostat control device also includes a temperature
`sensor for measuring the temperature in a space and gener-
`ating a temperature signal. The temperature signal is also
`sent to the controlling device. Multiple thermostat control
`devices can be connected to a single controlling device. The
`controlling device stores the setpoint temperature and mea-
`sured temperature for all thermostat control devices which
`are attached to it. It compares the setpoint temperatures and
`measured temperatures and controls the flow of warm/cool
`air to the spaces accordingly.
`The thermostat control device can be operated in either a
`day mode or a night mode. During day mode operation the
`thermostat control device transmits a temperature and set-
`point signal to the controller. The controller compares tem-
`perature and setpoint signals and adjusts the flow of warm/
`cool air appropriately. During night mode operation the
`controller compares the temperature signal from the ther-
`mostat contro] device with a night setpoint configured at the
`controller (or sometimes at the thermostat control devicc)
`for expected night occupancy. A mode override switch is
`provided on the thermostat control device for overriding
`night mode operation so that the controller, once again, uses
`the Day setpoint signal
`transmitted from the thermostat
`control device when adjusting the flow of warm/coolair.
`In one embodiment, the display device on the thermostat
`control device is used to display the sctpoint tempcraturc
`and the measured temperature. The display device is con-
`figured to display temperatures in either metric or standard
`engineering units. The display device is also configured to
`display whether the thermostat control device is operating in
`day mode or night mode.
`Aman-machine interface port is provided on the thermo-
`stat control device for connecting a maintenance terminal to
`the controller. By placing man-machine interface ports on
`the thermostat control devices, routine maintenance can be
`performed at any thermostat control device location. No
`
`30
`
`35
`
`40
`
`55
`
`60
`
`65
`
`4
`longer is a maintenance person required to find inconve-
`niently placed controllers in order to perform tasks such as
`controller setpoint adjustment.
`In another cmbodiment, the thermostat control device is
`configured with digital setpoint controls. A microprocessor
`is responsible for transmitting the setpoint to a networked
`controlling device. A man-machine interface port is included
`for connecting a man-machine computer to the controling
`device and for placing the microprocessor in an idle state
`when the man-machine computer is plugged in. The man-
`machine computer is configured to communicate directly to
`the controlling device and may be used for monitoring and
`controlling inputs and outputs of the controlling device. The
`man-machine interface (MMI) port provided on the thermo-
`stat control device with digital setpoint controls is also
`configured for receiving a hardware passkey. The hardware
`passkey is a pencil-like hardware security device which
`allows access into the point database of the controlling
`device. When the passkey is inserted in the MMI port,
`database information from the controlling device is dis-
`played onthe display of the thermostat control device. This
`will cnable the user to scroll
`through the point database
`stored in the controlling device and modify the database
`from the thermostat control device without the need for a
`maintenance terminal.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`FIG. 1 is a perspective view showing a front panel of an
`analog thermostat control device in accordance with the
`present invention;
`FIG.2 is an exploded perspective view of a setpoint adjust
`switch;
`FIG. 3 is a block diagram of an analog thermostat control
`device in accordance with the present invention;
`FIG.4 is a circuit diagram of one embodimentof a binary
`coded switch including a series resistor network;
`FIG. 5 is a two-dimensional graph showing howresis-
`tance of the series resistor network varies with respect to
`setpoint adjust switch position and setpoint temperature;
`FIG.6 is a circuit diagram of another embodimentof a
`binary coded switch including a parallel resistor network;
`FIG. 7 is a two-dimensional graph showing how resis-
`tance of the parallel resistor network varies with respect to
`setpoint adjust switch position and setpoint temperature;
`TIG. 8. is a two-dimensional graph showing how control-
`ler read current of the parallel resistor network varies with
`respect to setpoint adjust switch position and setpoint tem-
`perature;
`FIG. 9 is a perspective view showing a front pancl of a
`digital thermostat control device in accordance with the
`present invention;
`TIG. 10 is a block diagram of a digital room temperature
`sensor and thermostat control device in accordance with the
`present invention.
`
`DESCRIPTION OF THE PREFERRED
`EMBODIMENT
`
`invention presents an
`the present
`Broadly stated,
`improved thermostat control device. In the analog version, a
`binary coded switch is included for selectively setting a
`setpoint temperature. The binary coded switch contains a
`setpoint adjust switch, for setting the position of the binary
`coded switch, and a resistor network for producing a setpoint
`signal indicative of the binary coded switch position.
`
`013
`
`PETITIONER ECOBEE
`EX. 1010
`
`013
`
`PETITIONER ECOBEE
`EX. 1010
`
`

`

`5,934,554
`
`5
`Preferred embodiments of an improved thermostat control
`device are described herebelow with reference to the draw-
`ings.
`Ascricsresistor network is provided for systems in which
`a controlling device reads setpoint temperature as a function
`of resistance. A parallel resistor network is provided for
`systems in which a controlling device reads setpoint tem-
`perature as a function of current. The resistor networks are
`configured to produce a setpoint signal which varies linearly
`over the range of the binary coded switch.
`A digital thermostat control device is provided with a
`MMIport. The MMIportis configured to accept a hardware
`passkey. When the hardware passkey is inserted into the
`MMIport, point database information from the controlling
`device is displayed on the thermostat control device. The
`database information can be viewed and modified at
`the
`thermostat control device.
`
`‘Turning nowto the drawings, in particular FIGS. 1, 2 and
`3, the front pancl, a sctpoint adjust switch and a schematic
`block diagram of the analog thermostat control device are
`shown respectively. Located on the front panel 10 of the
`Analog, thermostat control device 12 is a setpoint adjust
`switch 14, an LCD display 16 and a mode override switch
`18. The setpoint adjust switch 14 is used to adjust
`the
`position of a binary coded switch 20. The LCD display 16
`is configured to display the room temperature.
`In the preferred embodiment, the setpoint adjust switch 14
`has 41 discrete positions. Each position corresponds to a
`setpoint temperature between and including 55° F. and 95°
`F. ‘Therefore, the setpoint temperature is adjusted by adjust-
`ing the position of the binary coded switch 20 using the
`setpoint adjust switch 14. Aswitch cover door 22 is provided
`on the front panel, and is configured to enclose and protect
`the setpoint adjust switch 14 whenclosed.
`As shownin FIG. 2, the setpoint adjust switch 14 consists
`of a housing 24, a wiper arm 26 and cap 26a, and a wiper
`28. ‘The wiper 28 has six separate electrically isolated blades
`which have opposite ends that contact six strips of conduc-
`tive surfaces 31a and 31b. The user selects a setpoint
`temperature by moving the wiper arm 26 to a position
`corresponding to the desired setpoint
`temperature.
`In
`response, the wiper 28 closes mechanical switches located in
`a resistor network 30 that are connected using the binary
`coded conductive surfaces 31a and 31b of a printed circuit
`board 33. The left end of the blades of the wiper 28 contact
`one of the solid conductive strips 316 whereas the right end
`of cach wiper blade will selectively contact various oncs of
`the binary coded surfaces 31a as a function of the position
`of wiper 28 along its path of travel. A controller 32 polls the
`resistor network 30 at predetermined intervals reading a
`setpoint signal 34 generated by the resistor network 30
`responsive to the position of the setpoint adjust switch 14.
`The controller 32 stores the setpoint information in a point
`database 36 along with other point information from all
`thermostat control devices connected to it.
`
`The analog thermostat control device 12 also contains a
`room temperature sensor 38 and a MM port 40. The NMI
`port 40 is configured to accept a connection from a main-
`tenance terminal. When the maintenance terminal is con-
`nected to the MMI port 40 the maintenance terminal takes
`control of the thermostat control device’s operation. The
`maintenance terminal can then be used to perform routine
`maintenance on the controller 32, such as controller sctpoint
`adjustment. When the maintenance terminal is unplugged
`from the MMI 40 the thermostat control device 12 resumes
`its normal operation.
`
`30
`
`35
`
`40
`
`50
`
`55
`
`60
`
`65
`
`6
`The room temperature sensor 38 measures the actual
`temperature in a space and generates a temperature signal
`indicative thereof. The controller 32 also polls the room
`temperature sensor 38 at predetermined intervals reading the
`temperature signal. The controller 32 stores the measured
`temperature information in the point database 36 with the
`other point information.
`The controller 32 compares the setpoint information and
`the measured temperature information stored in the point
`database 36 and generates a temperature adjust signal 42
`whichis sent to a heating/cooling unit 44. The temperature
`adjust signal 42 is indicative of the difference between the
`desired room temperature (sctpoint temperature) and the
`actual
`room temperature (measured temperature). The
`heating/cooling unit 44 attempts to adjust the actual room
`temperature to be equal to the desired room temperature by
`supplying heated or cooled air to the space.
`The controller 32 is also configured to have dual modes of
`operation, both a day mode and a night mode. During day
`mode operation, the controller 32 operates in the manner
`described above. In night mode operation, the controller 32
`compares the measured temperature information to a night
`setpoint programmed into the point database. The night
`setpoint is configured to conserve energy bysetting the night
`setpoint to reflect the reduced temperature control needed
`during periods when occupancy is usually reduced. The
`controller 32 is generally equipped with a timer which
`switches the mode of operation between day and night
`mode, and visa versa, according to a preprogrammed time
`schedule.
`
`
`
`The analog thermostat control device’s mode override
`switch 18 is used to override the controller 32 when it is in
`night mode. Whenthe user overrides night mode, by press-
`ing the mode override switch 18, the controller 32 switches
`back to comparing the measured temperature information to
`the setpoint information supplied by the thermostat control
`device 12 in calculating the temperature adjust signal 42.
`A series resistor network is shown in FIG. 4. Series
`resistor networks are desirable when the controller 32 is
`configured to read the setpoint temperature from the ther-
`mostat control device 12 as a function of resistance. In a
`6-bil binary coded switch, an intercept resistor 46 is con-
`nected in series with 6 setpoint resistors 48, 50, 52, 54, 56
`and 58. The setpoint resistor values are weighted im a binary
`fashion. In the preferred embodiment, setpoint resistor 48
`has a value of 10.5 ohms (), and setpointresistors 50, 52,
`54, 56 and 58 have values of 21.0 Q, 42.2 Q, 84.5 Q, 1692
`and 340Q respectively. Note that
`the setpoint resistors
`
`valucs arc approximately binary weightcd multiples of a
`
`primary value 10.50, with coefficients of 1, 2, 4, 8, 16 and
`32. Because actual EIA resistor values are not exact mul-
`tiples of two, the standard 1% values closest to the ideal
`calculated values are used in the preferred embodiment.
`A separate switch is connected in parallel with each
`setpointresistor. ‘The switches 60, 62, 64, 66, 68 and 70 are
`open by default but are configured to be closable by the
`setpoint adjust switch 14. When all switches are closed the
`intercept resistor 46 provides a minimum resistance value to
`be read by the controller 32. In the preferred embodiment,
`the intercept resistor 32 has a value of 866 Q.
`The setpoint adjust switch 14 is configured to open/close
`the switches in a binary coded fashion. In position zero,
`which corresponds to 55°, all switches are closcd, which
`corresponds to a binary coded value of 64 (O=open,
`1=closed). As the setpoint temperatureis raised, by moving
`the setpoint adjust switch 14, switches are opened/closed in
`
`014
`
`PETITIONER ECOBEE
`EX. 1010
`
`014
`
`PETITIONER ECOBEE
`EX. 1010
`
`

`

`5,934,554
`
`7
`a binary coded fashion increasing the resistance of the
`resistor network 30 and decreasing the binary coded value.
`For example, in position 1, the switch 60 is opened, corre-
`sponding to binary coded value of 63; in position 2, switch
`62 is opencd and 60is closed, in position 3 switches 60 and
`62 are both opened; in position 4, switch 64 is opened and
`switches 60 and 62 are closed, and so on until in position 40,
`switches 68 and 66 are closed and all other switches are
`open. Therefore, the resistance read by the controller 32
`varies with setpoint adjust switch position as shown in FIG.
`5.
`
`In a second embodiment shown in FIG. 6, a parallel
`resistor network is provided for systems in which the
`controller 32 reads the setpoint temperature as a function of
`current. In this embodiment, an intercept resistor 72 is
`connected in parallel with6 parallel setpoint resistors 74, 76,
`78, 80, 82 and 84. Again, the setpoint resistor values are
`weighted in a binary fashion. In this embodiment, setpoint
`resistor 74 has a value of 18.7 KQ,and setpointresistors 76,
`78, 80, 82 and 84 have values of 37.4 KQ, 75.0 KQ, 150
`KQ, 301 KQ and 604 KQ respectively. Note that
`the
`setpoint resistor valucs are approximatcly binary weighted
`multiples of a primary value 18.7 KQ, with coefficients of1,
`2, 4, 8, 16 and 32.
`Aseparate switch is connected in series with each parallel
`setpoint resistor. The switches 86, 88, 90, 92, 94 and 96 are
`open by default but are configured to be closable by the
`setpoint adjust switch 14. When all switches are closed, the
`intercept resistor 72 produces a maximumcurrent value to
`be read by the controller 32.
`In this embodiment,
`the
`intercept resistor 72 has a value of 14.3 KQ.
`The setpoint adjust switch 14 is configured to close the
`parallel switches in a binary coded fashion. In position zero,
`which correspondsto 55°, all switches are open correspond-
`ing to a binary coded value of zero. As the setpoint tem-
`perature is raised, by moving the setpoint adjust switch 14,
`switches are opened/closed in a binary coded fashion,
`incrcasing the binary valuc, decreasing the resistance and
`increasing the current of the resistor network 30. The
`resistance of the parallel resistance network varies non-
`linearly with respect to setpoint adjust switch position as
`shown in TIG. 7. This produces the linear relationship
`between controller read current and setpoint adjust switch
`position shown in FIG.8.
`FIGS. 9 and 10 show the front panel and a block diagram
`of a digital thermostat control device. Located on the front
`panel 98 of the digital thermostat control device 114 are
`setpoint adjust controls 102 and 104, a display control key
`106, an LCD display 108, a mode override switch 110 and
`a controls cover 112. The up-arrow setpoint adjust control
`102 is used to raise the setpoint temperature. The down-
`arrow setpoint adjust 104 is used to lower the setpoint
`temperature. The controls cover 112 is configured to enclose
`and protect the setpoint adjust controls 102 and 104 and the
`display control kcy 106.
`The LCD display 108 is configured to display the setpoint
`temperature or any other controller database point called a
`“critical point”, room temperature and mode of operation.
`The default display shows the room temperature and mode
`of operation. However, the user can select views showing
`critical point and mode of operation or room temperature,
`setpoint and mode of operation. In this embodiment, the
`digital thermostat control device 114 contains a micropro-
`cessor 116 for maintaining and transmitting setpoint tem-
`perature information to a controller 118. It also contains a
`room temperature sensor 120, and a man-machine/passkey
`
`3o
`
`35
`
`40
`
`50
`
`55
`
`6oa
`
`65
`
`015
`
`
`
`
`
`8
`interface port 124. The room temperature sensor 120 mea-
`sures the actual
`temperature in a space and generales a
`temperature signal indicative thereof. The microprocessor
`generates a setpoint temperature signal indicative of a set-
`point temperature set by the setpoint adjust controls 102 and
`104 and transmits the setpoint temperature signal to the
`controller. The controller
`reads the temperature signal
`directly from the room temperature scnsor. The controller
`118 stores the measured temperature and setpoint tempera-
`ture information in a point database 126 with other poimt
`information.
`The controller 118 compares the setpoint information and
`the measured temperature information stored in the point
`database 126 and generates a temperature adjust signal 128
`
`
`whichis sent to a heating/cooling unit 130. The temperature
`
`adjust signal 128 is indicative of the difference between the
`desired room temperature (setpoint temperature) and the
`actual
`room temperature (measured temperature). The
`heating/cooling unit 130 attempts to adjust the actual room
`temperature to be equal to the desired room temperature by
`supplying heated or cooled air to the space.
`Again, the controller 118 is configured to have dual modes
`of operation, both a day mode and a night mode, and the
`mode override switch 110 is configured to override the night
`mode. The digital thermostat control device 114 also con-
`tains a man-machineinterface port 124, similarto the analog
`thermostat control device 12, for connecting a maintenance
`terminal for use in performing maintenance tasks on the
`thermostat control device 114 and the controller 118. When
`a maintenance terminal is plugged into the MMT port 124,
`the microprocessor 116 is placed in an idle state and the
`maintenance terminal assumes control. When the mainte-
`nance terminal is disconnected the microprocessor 116 and
`the thermostat contral device 114 resume normal operation.
`
`
`In an effort to makeit easier to maintain the point database
`126, there for port 124 is provided on the digital thermostat
`c