Patent Publication Number: US-2013253714-A1

Title: Irrigation Controller With Removable Station Modules

Description:
RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 13/332,158 filed Dec. 20, 2011 entitled Irrigation Controller With Removable Station Modules, which is a continuation of U.S. patent application Ser. No. 13/016,844 filed Jan. 28, 2011 entitled Irrigation Controller With Removable Station Modules (now abandoned), which is a continuation of U.S. patent application Ser. No. 12/760,356 filed Apr. 14, 2010 entitled Irrigation Controller With Removable Station Modules (now abandoned), which is a continuation of U.S. patent application Ser. No. 12/023,972 filed Jan. 31, 2008 entitled Irrigation Controller With Removable Station Modules (now abandoned), which is a continuation of U.S. patent application Ser. No. 11/282,454 filed Nov. 17, 2005 entitled Irrigation Controller With Removable Station Modules (now abandoned), which is a continuation of U.S. patent application Ser. No. 10/887,367 filed Jul. 6, 2004 entitled Irrigation Controller With Removable Station Modules (now U.S. Pat. No. 6,996,457 issued Feb. 7, 2006), which is a continuation of U.S. patent application Ser. No. 10/198,849 filed Jul. 19, 2002 entitled Irrigation Controller With Removable Station Modules (now U.S. Pat. No. 6,772,050 issued Aug. 3, 2004), which is a continuation of U.S. patent application Ser. No. 09/400,031 filed Sep. 21, 1999 entitled Irrigation Controller With Removable Station Modules (now U.S. Pat. No. 6,459,959 issued Oct. 1, 2002), which is a continuation of U.S. patent application Ser. No. 08/904,125 filed Jul. 28, 1997 entitled Irrigation Controller With Removable Station Modules (now U.S. Pat. No. 5,956,248 issued Sep. 21, 1999), which is a continuation of U.S. patent application Ser. No. 08/312,268 filed Sep. 23, 1994 entitled Irrigation Controller With Removable Station Modules (now abandoned), all of which are incorporated herein by reference in their entireties. 
    
    
     TECHNICAL FIELD 
     This invention relates to an irrigation controller for controlling the operation of an irrigation system pursuant to a watering schedule that may be programmed by the user. More particularly, this invention relates to an irrigation controller for controlling multiple irrigation stations. 
     BACKGROUND OF THE INVENTION 
     Irrigation controllers are known for controlling the operation of an irrigation system in accordance with the passage of time. Most controllers operate a plurality of watering stations and will retain or store a watering program established by the user. This program typically allows the user to pick what days the sprinklers will operate, what time of day that irrigation will begin, and how long each station will operate. Some controllers allow multiple watering programs to be stored. 
     U.S. Pat. No. 5,262,936 discloses a microprocessor based controller in which the controller base unit has drivers and switches for controlling some number of irrigation stations that is less than the maximum number that can be controlled. The station handling ability of the controller can be expanded by plugging in additional modules with each module having drivers and switches for an additional number of stations. The modules when connected extend and are part of a serial bus structure in the controller. The modules known in this prior controller are quite large and when connected to the base unit of the controller take up considerable space exteriorly of the base unit, leading to problems in finding sufficient space to receive them all and in attaching all of the modules in a secure fashion. 
     SUMMARY OF THE INVENTION 
     This invention relates to an irrigation controller which comprises a housing having microprocessor means for storing and executing a watering program for controlling a plurality of irrigation stations. The microprocessor means includes a parallel output bus within the housing having a plurality of separate station output pins for controlling the irrigation stations with one station output pin used for controlling each station. At least one module is removably plugged into at least one of the station output pins on the output bus. The module has a terminal suited for receiving an electrical lead wire extending to the irrigation station, and further has driver and switch means for activating the station as commanded by the base unit over the at least one station output pin. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       This invention will be described in more detail in the following Detailed Description, taken in conjunction with the following drawings, in which like reference numerals refer to like elements throughout. 
         FIG. 1  is a front elevational view of an improved irrigation controller according to this invention, particularly illustrating the controller housing and front panel with its associated controls and displays and having a portion of the controller broken away to illustrate one of the removable station modules installed inside the controller housing; 
         FIG. 2  is a side elevational view of the controller shown in  FIG. 1 , particularly illustrating the controller housing and its attachment to a mounting bracket on which the controller housing is removably installed; 
         FIG. 3  is a top plan view of the controller shown in  FIG. 1 , particularly illustrating the controller housing and its mounting bracket; 
         FIG. 4  is a bottom plan view of the controller shown in  FIG. 1  with the controller housing in place on its mounting bracket; 
         FIG. 5  is an exploded, rear elevational view of the controller shown in  FIG. 1 , particularly illustrating the controller housing detached from the mounting bracket and the pocket provided on the back of the controller housing for holding a user manual for the controller; 
         FIG. 6  is an enlarged front elevational view of one of the station modules of the controller with the module shown installed in the controller of  FIG. 1 ; 
         FIG. 7  is a cross-sectional view taken along lines  7 - 7  of  FIG. 6 , particularly illustrating how the station module is installed in the controller of  FIG. 1 ; 
         FIG. 8  is a partial front elevational view of the controller shown in  FIG. 1 , with the terminal strip cover being removed to show two station modules for controlling four irrigation stations and the rain sensor, 24 V AC and pump and common outputs contained on the terminal strip; and  FIG. 9  is a schematic diagram of one of the station modules used in the controller of  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION 
     This invention relates to an irrigation controller  2  for controlling the operation of an irrigation system in a timed manner. More specifically, controller  2  allows the user to select or input at least one watering program comprising the following parameters of irrigation system operation:
         which days the sprinklers will operate in a particular 7 day window (i.e. a calendar sequence) or the interval between successive operational days up to a maximum interval of 7 days (i.e. an interval sequence), the operational days being known as “active days”;   when the sprinklers come on during the active days, known as the “start times”, with up to four start times being selectable; and   how long the sprinklers will run after each start, known as the “run times”.       

     Controller  2  is adapted to control a plurality of separate watering “stations” in the irrigation system. Each station comprises one or more sprinklers grouped together to operate simultaneously off the same irrigation valve V. Each irrigation valve V includes an actuator, such as an electrical solenoid S, which is operated by a control signal from controller  2  to turn valve V on. 
     Controller  2  of this invention can be easily adapted to control different numbers of stations up to a total of eight stations. A four station controller  2  is illustrated in this application. Referring to  FIG. 8 , the four stations are illustrated by the four separate irrigation valves V 1 , V 2 , V 3  and V 4  wired to controller  2 . There will be six irrigation valves V 1 -V 6  wired to controller  2  in a six station controller, eight valves V 1 -V 8  in an eight station controller, and so on. While eight is the maximum number of stations that can be controlled by controller  2  shown herein, the maximum number of stations can obviously be adjusted to a larger number if so desired. 
     For each watering program stored in controller  2 , a run time may be set individually for each separate station, i.e. different stations may have different run times depending on operator preference. However, the selections of active days and start times apply to all stations as a group within each watering program. Thus, when an active day and start time is reached when executing a particular watering program, controller  2  will operate the irrigation system by sequencing through the stations and operating each station for the run time which has been set for that station on that particular program. Sequential operation of the stations is preferred to decrease the demands on the water delivery capacity of the irrigation system. 
     Controller  2  incorporates a microprocessor (not shown) of any suitable design which comprises a timing, memory, logic and control means. The microprocessor monitors the passage of time and executes whatever watering program has been input and selected by the user for execution. Operational flexibility is achieved by allowing controller  2  to store and execute multiple watering programs so that a different combination of active days, start times, and run times can be stored in different programs if so desired. The microprocessor can also permanently store a default watering program for use if the user fails to input a customized watering program or programs of the user&#39;s own design. 
     Typical irrigation controllers based on the use of microprocessors are disclosed in U.S. Pat. Nos. 5,262,936 and 5,272,620, owned by the assignee of this application. These patents are hereby incorporated by reference. 
     Referring to  FIG. 1 , the electronic components of controller  2 , including the microprocessor, are contained within a housing  4  of any suitable design. As will be described in more detail hereafter, housing  4  may be mounted on a wall  5  using a mounting bracket  6 . Housing  4  includes a front panel  8  having various operational controls which may be manipulated by the user to activate control functions of controller  2  or to input information into controller  2 . In addition, controller  2  includes a display device  10  for displaying information to the user. 
     The operational controls of controller  2  include a rotary knob or dial  12  for selecting various ones of the programmable parameters that can be input and stored in a watering program, and various push button controls identified generally as  14 . Push button controls  14  include “up/down” or “plus/minus” keys  14   a,    14   b  for incrementing or decrementing the value of a particular parameter when programming the controller, an “enter” key  14   c  for accepting a particular value of a parameter and for proceeding to the next step in the programming sequence, and an “escape” key  14   d  to start over during programming. Thus, by rotating dial  12  to a particular position corresponding to a particular parameter that can be input, the user can then manipulate controls  14  to input and store values for the selected parameter while observing in display device  10  the values as they are being input for that parameter through the operation of controls  14 . 
     The type of watering program stored in controller  2 , namely the number and nature of the parameters that can be set and stored in a watering program and then executed by controller  2 , can obviously be varied. In addition, the nature of the operational controls  12 ,  14  used to input the watering program or access the features of controller  2  can also obviously be changed. This invention relates to other features of controller  2 , to be described in detail hereafter, that can be used generally on any irrigation controller that controls a plurality of stations, without being limited to controller  2  as shown herein. 
     A lower portion of controller  2  houses an input/output terminal area, identified generally as  16 , behind an easily removable access strip or panel  18 . Panel  18  is configured to snap onto and off of controller housing  4  using known tab and slot connections. Terminal area  16  includes space for three, terminal blocks  20   a,    20   b,  and  20   c  which are hardwired into place. In addition, terminal area  16  includes space for up to four, two-station modules  22   a,    22   b,  etc. that are used to connect controller  2  to the irrigation stations comprising valves V. Station modules  22  are generally identical to one another and are easily removable from controller  2 —modules  22  simply plug into controller  2  and can be easily unplugged from controller  2  in a manner to be described shortly. 
     Terminal blocks  20  and station modules  22  each have two snap-in wire terminals  24   a,    24   b  therein for receiving two connecting wires. Such terminals are well known in the electrical connection art. They each have a pivotal lever  26  that may be rotated 90° from an open position (where lever  26  is vertical and the wire may be inserted into the terminal) to a generally closed position (where lever  26  is horizontal and the wire is clamped or retained in the terminal). The use of such snap-in wire terminals is preferred as it eases the task of connecting the necessary wires to controller  2 . Other quick coupling devices could be used, or conventional screw type terminals could be used, in place of snap-in terminals  24   a,    24   b.    
     The nature of the wires that are connected to the various terminal blocks  20  and station modules  22  will vary. For example, the first terminal block  20   a  connects to the two lead wires of a rain switch (not shown) which determines if it is raining and allows controller  2  to cease operation in the case of rain. A typical rain switch of the type which may be connected to terminal block  20   a  is described in U.S. Pat. No. 5,101,083, which is hereby incorporated by reference. An on/off switch  28  can be mounted in terminal area  16  immediately above terminal block  20   a  for the rain switch. In the off position of switch  28 , the rain switch input is ignored by controller  2  such that the detection of rain will not affect the operation of controller  2  or the irrigation system. 
     The second terminal block  20   b  is used for the convenient connection of an external electrical transformer  30  used to provide AC power to controller  2 . Transformer  30  will be wired or plugged into a standard AC power source such as 120V AC power, and will provide 24V AC power to controller  2 . Ultimately, such 24V AC power will be used to activate solenoids S on irrigation valves V. Additionally, such power can be routed through one of the terminals in terminal block  20   c  to activate a solenoid S on a master valve or a relay on an irrigation pump. This is required in irrigation systems where a source of pressurized water is not continually present upstream of valves V, but is provided only when irrigation is to take place. In this event, either a master valve supplying valves V must first be opened, or a pump started, to ensure supply of pressurized water to valves V. 
     The third terminal block  20   c  as noted above uses one of the snap-in terminals, namely terminal  24   a,  as a master valve or pump relay output for supplying 24V AC power from controller  2  to these components. The other terminal  24   b  in terminal block  20   c  is used as a common wire connection COM to ground. Thus, all of the common wires for all of the irrigation valves V may be spliced together, as shown in  FIG. 8 , and connected to ground using the common wire terminal  24   b  in terminal block  20   c.  In addition, when operating a master valve or pump, the common wire for such master valve or pump may also be spliced into and connected to the common wire connection COM leading to common wire terminal  24   b.    
     Station modules  22  are used to allow controller  2  to control a desired number of stations determined by the number of modules  22  that are installed. Each module  22  has two snap-in terminals  24   a,    24   b  for controlling two stations, with each terminal being connected to the non-common wire lead from a solenoid S. A module  22  could be used to control only one station if only of the snap-in wire terminals  24   a,    24   b  is connected to a single solenoid. However, if both terminals are being utilized, then each module  22  will control two stations, i.e. two of the irrigation valves V. See  FIG. 8 . 
     Controller  2  is provided with means for accepting up to a predetermined maximum number of modules  22  to control up to a predetermined maximum number of stations V. There is space in controller  2  for accepting up to four modules  22  side-by-side in terminal area  16 , thus allowing up to eight stations to be controlled. If one module  22  is installed, then up to two stations can be controlled, with two modules  22  up to four stations can be controlled, and so on.  FIG. 8  illustrates a configuration having two modules installed controlling four stations represented by the four irrigation valves V 1 -V 4 . 
     Referring to  FIGS. 1 ,  6  and  7 , each station module  22  includes a casing  32  having a generally rectangular base  34  secured to a tapered top  36 . Base  34  and top  36  may be separable to allow a printed circuit board to be inserted into module  22  during manufacture, with base  34  and top  36  then being snapped together and held as a unit by suitable connectors  38 . One end of module  22  includes the two snap-in wire terminals  24   a,    24   b  representing the output end of module  22 . The other or input end of module  22  has a plug connection for allowing module  22  to be plugged into one set  40  of four output pins  42  on a parallel output bus in controller  2 . In each set  40  of pins  42 , one pin is assigned to control one of the terminals  24   a  and  24   b,  respectively, another pin is a ground connection, and the remaining pin is a 5V power input to module  22 . See  FIG. 9 . Thus, when module  22  is in place and is plugged into the parallel output bus, controller  2  will activate the stations connected to module  22  as called for by the watering program being executed by controller  2 . 
     Terminal area  16  of controller  2  is provided with four slots  44  in which modules  22  are slidably received, with one slot  44  being provided for each module  22 . Each slot  44  is formed by the upper aligned surfaces  48  of a plurality of spaced vertical walls  50  in terminal area  16 , such surfaces  48  defining a plane against which the bottom of module  22  may be engaged. Each slot  44  further has two spaced overhanging lips  52  on either side thereof which are spaced from one another and are elevated above the upper aligned surfaces  48  of walls  50 . Lips  52  are suited to slidably engage with a plurality of guide tabs  54  that jut out from the sides of modules  22  to guide modules  22  in slots  44 . 
     As shown most clearly in  FIG. 7 , to insert a module  22  into one of the slots  44  in terminal area  16 , module  22  is positioned as shown in phantom above slot  44  and with guide tabs  54  on modules  22  being located in the gaps between the spaced lips  52 . Module  22  is then dropped downwardly until the bottom thereof rests on the upper aligned surfaces  48  of vertical walls  50 . Module  22  is then pushed inwardly in slot  44  relative to the parallel output bus until the pin set  50  on the bus plugs into the connector provided therefor in the input end of module  22  as shown in solid lines in  FIG. 7 . In this position, guide tabs  54  on module  22  have slid beneath lips  52  on the sides of slots  44 . 
     The top of each module is provided with means forming a spring biased latch. More specifically, this latch is provided by a section  60  of the top wall of module  22  that is cut away along its sides and rear but is joined to module  22  at the front, in effect being supported in the manner of a cantilever. This section  60  will have a natural outward biasing force which tends to keep this section  60  aligned with the remaining portions of the top wall of module  22 . The rear of section  60  is provided with an upwardly protruding hook  62 . Hook  62  is adapted to engage against the rear side of a vertical wall  64  that overlies the inner end of slot  44 . 
     As module  22  is slid into place in a slot  44  (after it has been dropped into place in slot  44  with guide tabs  54  ready to be pushed beneath lips  52 ), hook  62  will be cammed down beneath wall  64  with the cut away top wall section  60  deflecting down as necessary to allow this movement. When hook  62  clears wall  64  as module  22  plugs into the pin set  40  on output bus, the cut away section  60  of the top wall  55  will spring back upwardly to its normal untensioned state where it is generally aligned with the remainder of the top wall. Thus, hook  62  and cut away section  60  of the top module wall form, in effect, a spring biased latch for firmly locking module  22  in place in slot  44 . 
     To remove any particular module from its slot  44 , the user simply presses down on the cut away section  60  of the top wall to disengage hook  62  from behind wall  64 , and then pulls slightly outwardly on module  22  to clear guide tabs  54  from beneath lips  54  and to unplug module  22  from the output bus. Module  22  is then simply lifted up out of slot  44 . Thus, the actions required to remove a module  22  are the reverse of those used to install module  22 . 
     The electronic circuitry for activating the solenoid S on the valves V is contained on the printed circuit board that is carried within each module  22 . Referring to  FIG. 9 , this circuitry comprises a transistor driver  70  for activating a TRIAC switching device  72 . Each terminal  24   a,    24   b  is connected to its own transistor/TRIAC combination  70 / 72 . Thus, when controller  2  determines that a particular valve V should be opened, it does so by activating the appropriate transistor  70  to close the appropriate TRIAC 74, thus activating the solenoid of the appropriate valve. 
     The use of plug in, removable station modules  22  for serving as the connection to the irrigation stations allows controller  2  to have great versatility. If only a four station controller is needed, only two modules  22  need be used. Thus, the user can tailor controller  2  to control precisely only those numbers of stations that are required for a particular irrigation system. In addition, modules  22  are all conveniently located within, and protected by, housing  4  of controller  2 . Thus, controller  2  is compact and not unduly bulky. The bottom of controller housing  4  includes various ports or openings  80  for routing wires to and from terminal area  16  for connection to terminal blocks  20  or station modules  22 . See  FIG. 4 . 
     The Applicants have found that controller  2  will have great resistance to lightning strikes that may induce surge currents on the station wires. In previous controllers, the energy from such a strike will often be conducted back to controller  2  along the wires connecting controller  2  to the particular station affected by the strike. Since these wires are usually connected directly to a terminal strip that is hardwired to the main printed circuit board of controller  2 , i.e. to the circuit board having the microprocessor controller, this energy could often damage many of the controller&#39;s components, including the microprocessor. 
     However, with modules  22  of the present invention, Applicants have found that much of the energy from a lightning strike will be absorbed by the electronic circuitry within module  22  without damaging the main printed circuit board in controller  2 . Thus, while module  22  itself may be destroyed by the lightning strike, it is a simple matter to replace this module with a new one. This is an easy and inexpensive task compared to the cost of repairing or replacing the main circuit board of the entire controller  2 . 
     Turning now to the mechanical mounting of controller  2  on the wall, the mounting bracket  6  includes a planar surface  82  that may be screwed or in some other way fixed to the wall. A pocket receiving space  83  is formed on this mounting bracket  82  which is bounded by two spaced side walls  84 , by a bottom wall  86  and by the planar surface  82  of bracket  6 . This space  83  has a predetermined depth determined by the depth of side walls  84 . Each side wall  84  has an outwardly protruding tab  88  on the front side thereof spaced away from planar surface  82  by an appropriate distance. 
     The rear surface of controller  2  housing has a bayonet type slot structure  90  for receiving tabs  88  on mounting bracket  6 . Basically, each tab  88  is initially received into an open rectangular portion  92  of slot  90 , and controller housing  4  can then be slid down relative to mounting bracket  6  until tabs  88  are received behind wall portions  94  of slot  90 . Thus, controller housing  4  can be removably attached to wall  5  using mounting bracket  6 , and can be slid onto and off of mounting bracket  6  at will. 
     The rear surface of controller housing  4  includes a rearwardly protruding pocket  96  for holding a user&#39;s or operator&#39;s manual  98 . The depth and size of pocket  96  is sufficient to allow pocket  96  to be received in the pocket receiving space  83  provided on bracket  6  between side walls  84 . Thus, when controller housing  4  is in place on mounting bracket  6 , the space  83  between housing  4  and the planar surface  82  of mounting bracket  6  is used to conveniently store the user&#39;s manual  98 . See the phantom line illustration in  FIG. 2 . 
     It is a great advantage to have the user&#39;s manual located in a readily accessible manner on controller  2  housing. The user need not go look for the manual in some remote space when some question arises as to the programming or operation of controller  2 . In addition, the manual storage is done in an out-of-the way, unobtrusive location, thus enhancing the probability that it will be used for this purpose. 
     Various modifications of this invention will be apparent to those skilled in the art. Thus, the scope of this invention is to be limited only by the appended claims.