« PreviousContinue »
United States Patent [w]
Specht et al.
US006053416A [ii] Patent Number:  Date of Patent:
 AUTOMATIC HYDRONIC ZONE VALVE AND ELECTRIC CONTROLS THEREFOR
 Inventors: James Specht, Olyphant; Joseph Contardi, Scranton, both of Pa.
 Assignee: KCI Industries, Inc., Jessup, Pa.
 Appl. No.: 08/959,930  Filed: Oct. 29, 1997
 Int. C I. 1241) 3/02
 U.S. CI 236/75; 236/1 B; 237/8 A
 Field of Search 236/75, 1 B, 9 A;
237/8 R, 8 A
 References Cited
U.S. PATENT DOCUMENTS
1,167,815 1/1916 Gold .
1.791,964 5/1927 Kleinhaus et al. .
2,126,732 8/1938 Carnes 237/19
2,240,731 5/1941 Van Vulpen 237/8
2,255,904 9/1941 Smith 237/6
2,310,745 2/1943 Parks et al 137/139
2,323,236 6/1943 Parks et al 257/3
2,493,365 1/1950 Schramm 237/9
3,123,296 3/1964 Wantz et al 236/99
3,170,630 2/1965 Chadwick 236/1 B
3,351,128 11/1967 Barnd 165/22
3,446,473 5/1969 Barker 251/64
3,610,523 10/1971 Troy 237/8
3,625,476 12/1971 Meier 236/75 X
3,914,952 10/1975 Barbier 236/75 X
4,595,170 6/1986 Levit .
4,620,260 10/1986 Oshizawa et al. .
5,125,433 6/1992 DeMoss et al. .
5,199,456 4/1993 Lore et al. .
FOREIGN PATENT DOCUMENTS
2742754 3/1978 Germany .
59-154007 9/1984 lapan .
04153542 5/1992 lapan .
07260035 10/1995 lapan .
07332530 12/1995 lapan .
Primary Examiner—Harry B. Tanner
Attorney, Agent, or Firm—Richard R. Mybeck; Peter B.
An automatic and improved electrical control for an automatic hydronic zone valve including a switching device for opening and closing solenoid valves based on adjustable temperature settings. Specifically, the preferred system involves a solenoid-controlled valve in which the solenoid is activated and deactivated by an electrical control circuit which relies on an external thermostatic switch and an internal relay to open and alternately close the following sub-circuits: a solenoid control sub-circuit which is directly connected to the valve solenoid, an AC to DC converter, relay control circuitry, a relay switch connection to a water circulator system and LED sub-circuits indicating power status and/or activation of the heating system. The solenoid control sub-circuit includes a series thermistor and a parallel capacitor to, respectively, slow the provision of electrical current to the solenoid to avoid "water hammer," and, quiet the electronic hum of the solenoid. Moreover, the current invention also involves simplified wiring such that only two wires each are necessary for thermostat connection, for power supply connection and for water circulator connection. But for these three external connection sites, all the other control circuit elements are disposed in a single compact unit, preferably housed on the solenoid valve itself.
18 Claims, 2 Drawing Sheets
AUTOMATIC HYDRONIC ZONE VALVE AND
ELECTRIC CONTROLS THEREFOR
The present invention is directed generally to automating 5 hydronic zone valves with the use of electrical controls which are activated by ambient temperature changes and are especially designed to eliminate the "water hammer" and noisy solenoid "humming" that are characteristic of many commercially available systems. The electrical controls hereof also introduce new simplified wiring schemes which can be used in new systems as well as in the replacement of valves in existing hydronic systems.
BACKGROUND OF THE INVENTION 15
In the field of hydronics generally, temperature-controlled solenoid valves have been known since at least as early as 1916 when U.S. Pat. No. 1,167,815 issued to E. E. Gold. Gold disclosed a thermostat which was adjustable to be set 20 to a preselected temperature so that when a sufficient change in temperature occurred, the thermostat acted as a switch to open or close a solenoid valve control circuit. When this circuit was closed by the thermostatic switch, power was supplied to a solenoid valve which energized the valve and 25 caused the valve to close. When the circuit was opened, the power was discontinued to the solenoid which when de-energized thereby allowed the valve to open. When the valve was thus opened, temperature-conditioned water flowed through the valve to a radiator or a similarly asso- 30 ciated temperature conditioning and/or circulating device to provide heating (or cooling) to a room or a like hydronic zone with which the thermostat and radiator was associated.
Numerous advancements have since been introduced to the art, particularly toward the reduction of certain noises 35 associated with valve operations. These later teachings have included mechanical and/or electrical devices for noise reduction. Examples of such devices include different types of springs, dampers, TEFLON seats, relays, rectifiers, thyristors, zener diodes, and pulse-generating circuits. 40 However, there still appears to be a need for improvements particularly in providing devices which reduce water hammer and solenoid humming in user-friendly and inexpensive devices.
Moreover, many conventional zone valves have other 45 drawbacks as well. For example, many prior art valves require a three-wire thermostat with complicated wiring between the power supply, the thermostat and the solenoid valve or, they require a separate relay to convert the threewire thermostats to less complicated two-wire thermostat 50 installations. A conventional three-wire thermostat zone valve setup is shown, for example, in the U.S. patent to L Troy (U.S. Pat. No. 3,610,523). In the Troy system, each independent thermostat has three electrical contacts which comprise, in essence, a single-pole, double-throw ("SPDT") 55 switch. In use, one contact is for the common line (also identified by the letter R in the conventional R, W, B lettering scheme) from the power source, the other two are for two distinct sub-circuits; namely a solenoid sub-circuit and a circulator sub-circuit. When switched to place the 60 common line in contact with and close the solenoid subcircuit, power is then supplied to a solenoid valve to close the valve. On the other hand, when the thermostat switch is moved by the appropriate temperature change to open the solenoid sub-circuit, the power to the solenoid is stopped 65 which allows the valve to open. A still further effect of a sufficient, preselected temperature change is to connect the
common line with the circulator sub-circuit to close that sub-circuit. When this sub-circuit is closed, power is provided to the circulator and/or boiler relay which causes the motor and pump to circulate the temperature conditioned water through the hydronic system. This is demand circulation.
Even so, two-wire thermostatic connections to solenoid valves are preferable because they offer greater simplicity in the wiring of such systems. However, this has heretofore been unavailable with the demand circulation functionality of a three-wire thermostat in a Troy-type of system. Therefore, the provision of a temperature-activated solenoid control which enables demand circulation in a simple twowire thermostat wiring system would be a distinctive achievement.
BRIEF SUMMARY OF THE INVENTION
The present invention is directed generally to solenoid valves and solenoid valve control systems. More particularly, the present invention is directed to controls which provide, inter alia, automatic and improved switching for opening and closing solenoid valves based on preferred and adjustable temperature settings. Specifically, as will appear, the system of the present invention involves a solenoid-controlled valve in which the solenoid is activated and deactivated by an electrical control circuit which relies on an external thermostatic switch and an internal relay to open and alternately close various sub-circuits, one of which being a solenoid control sub-circuit which is directly connected to the valve solenoid. The other sub-circuits preferably include an AC to DC converter, a relay control subcircuit, a relay switch connection to the water circulator system and LED sub-circuits indicating power status and/or activation of the heating system. The solenoid control subcircuit includes a series thermistor and a parallel capacitor to, respectively, slow the delivery of electrical current to the solenoid to avoid "water hammer," and, quiet the electronic hum of the solenoid.
Moreover, the current invention also involves simplified wiring so that only two wires are necessary for the thermostat connection, only two other wires are necessary to connect to the power supply and only two more wires are necessary to connect to the water circulator. Except for these three external connections, all the other control circuit elements are disposed in a compact unit which is preferably housed in a compartment on the solenoid valve itself
Accordingly, a primary object of the present invention is to provide an automated solenoid valve control system which substantially reduces mechanical and electrical noise emissions from the operating system.
Another object of the present invention is to provide an automatic hydronic zone valve which substantially reduces the "water hammer" effect which can be caused by a rapid closure of a solenoid valve.
Yet another object of the present invention is to provide an automatic hydronic zone valve which substantially reduces the humming often caused by electrical solenoid systems.
Still another object of the present invention is to provide an automatic hydronic zone valve which provides an automated solenoid valve control appliance which is compact, and may be inconspicuously disposed on or in close association with the solenoid valve itself.
Still one further object is to provide solenoid valve control and demand circulation in one simple-to-wire, readily installable device.
These and still further objects, as shall hereinafter appear, are readily fulfilled by the present invention in a remarkably