JP2000173382A - Contact control system, contact control device and equipment controller provided therewith - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the cost of a system, to prolong the lifetime of a contact, and to detect the contact fusion. SOLUTION: This system is provided with normally open contacts 23, 24 arranged in a power source line 18 for connecting a power source 22 and a circulation pump 15 to each other, a control circuit 29 for alternately controlling the contacts 23, 24 for opening operation first so as to release the closing condition thereof, and a current detecting circuit 28 for detecting the current flowing in the power source line 18. The control circuit 29 detects the fusion of the contacts 23, 24 on the basis of the output of the detection from the current detecting circuit 28 with the opening and closing timing of both the contacts 23, 24.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a contact control system, a contact control device, and an equipment controller including the same.

[0002]

2. Description of the Related Art In general, for example, a jet bath controller as a device controller circulates hot and cold water in a jet bath by driving a circulation pump and controls jetting of hot and cold water from a plurality of bubble jet ports on the side surface of the jet bath. Has become. In such a jet bath controller, it is necessary to cut off the power supply line which is a power supply line for driving the circulating pump as soon as a leak occurs. Have.

[0003] A conventional contact control device in such a jet bath controller includes the one described with reference to FIG. A zero-phase current transformer 4 is provided on a pair of power lines 3 between the circulating pump 1 and the AC power supply 2. 4 has no voltage output from the zero-phase current transformer 4 in a state where no current flows apparently, but when a current leaks between the circulating pump 1 and the ground due to water or the like and a leakage occurs, each power line 3 A voltage is generated due to the difference in current flowing between the zero-phase current transformers 4
Outputs a voltage as a leakage voltage. Leakage detection circuit 5
Outputs a leakage detection output to the relay coil 6 in response to the input of the leakage voltage. The relay coil 6 is energized by the detection output from the leakage detection circuit 5 to drive the leakage control relay contact 7 which is a 2b contact (normally closed contact) inserted into the power supply line 3 to the open side. As a result, the power supply line 3 is cut off, and the supply of the AC power supply 2 to the circulation pump 1 is cut off.

[0004] The supply of the AC power supply 2 and the supply of the AC power supply 2 to the circulating pump 1 in which the supply of the AC power supply 2 is cut off in the event of an electric leakage in response to a hand operation of a bather to use the bathtub as a jet bath, for example, In order to control the stop of the operation, an output control relay contact 8 which is a 2a contact (normally open contact) is inserted and connected to the power supply line 3, and the relay coil 10 is energized in response to a control output from the control circuit 9. In some cases, the relay contact 8 can be driven to the closed side so that the AC power supply 2 is supplied to the circulating pump 1 to drive it.

[0005]

In the above-mentioned contact control device, the output control relay contact 8 of the 2a contact type and the earth leakage control relay contact 7 of the 2b contact type are required. This increases the cost of a system using this contact control device, and the expensive 2b
There is a problem that a contact is required, which also increases the cost of the system.

Although the output control relay contact 8 is a 2a contact, it must be driven at the same time. However, due to the mechanical structure, the output control relay contact 8 is not completely driven at the same time. There is a problem in that the contact life of one of the contacts is shortened by the drive to the open side and the drive to the circulation pump and the non-drive repeatedly.

Accordingly, the present invention provides a power supply line for connecting a power supply and a load with a plurality of contacts, and controls the output timing of a drive signal for each of the contacts so that the contacts can be moved relative to each other. By alternately opening drive first or alternately closing drive alternately, it is possible to use both output control and earth leakage control and to reduce the number of contacts, thereby reducing the cost of the system, and It is an issue to be solved to extend the life of the contact.

In the above case, when a contact is connected to each of a pair of power supply lines, and both contacts are used for output control and leakage control, only one of the contacts is welded and does not open. There is a problem. That is, the output control for the circulating pump can be dealt with by opening and closing the other contact, but in the case of a leakage, the leakage breaker forcibly opens the two contacts in conjunction with one another. If there is welding only on the contact side, the other contact cannot be forcibly opened and cannot cope with leakage.

In view of the above, the present invention also provides a configuration in which when a contact is used for both output control and leakage control, the welding of the two contacts can be detected early and reliably. Another problem to be solved is to make it possible to quickly take necessary countermeasures when the contacts cannot be forcibly opened and to improve the reliability of the system using the contact control device.

[0010]

According to the contact control device of the present invention, a plurality of normally open contacts provided on a power supply line between a power supply and a load are alternately first closed or controlled alternately. Control means for outputting a plurality of drive signals for controlling the release of the closing drive first, leak detection means for detecting a leak in the power supply line, and current detection means for detecting a current flowing in the power supply line An output prohibition unit that prohibits a signal output when a leakage detection output is input from the leakage detection unit, and a plurality of driving units that individually drive each of the contacts. Each of the plurality of drive signals is output to each of the plurality of drive means via the output prohibiting means, and the timing of the open / close state of each of the contacts is determined based on a detection output of the current to determine each of the plurality of drive signals. It is configured so as to detect the welding state. Thus, the control unit outputs the drive signal to the drive unit, and thereby can open and close each of the two contacts for output control. As a result of prohibiting the output to the means, even if a drive signal is output from the control unit, each of the two contacts is held open without being opened / closed by the drive signal, so that it is possible to deal with the occurrence of electric leakage, The contacts can be used for both output control and leakage control. Then, the control unit can determine the welding state of both contacts from the output of the current detecting means, so that a necessary measure can be taken in a case where both contacts cannot be forcibly opened and driven by the leakage breaker when a leakage occurs. This solves the above-described problem.

[0011]

Embodiments of the present invention will be described below in detail with reference to the drawings. Although the present invention is described as being applied to a jet bath controller as a device controller, the present invention is not limited to this jet bath controller alone. Further, the present invention provides a contact control system including a contact to be described later, and a device for controlling the contact is a contact control device.

FIG. 1 shows a jet bath controller as an equipment controller to which a contact control device according to an embodiment of the present invention is applied. A jet bath 12 is provided in a bathroom 11. The jet bath 12 has a bubble jet port 13. The bubble outlet 13 is connected to a circulation pump 15 via a pipe 14. Circulation pump 1
Numeral 5 circulates the hot water in the jet bath 12 as described above, and makes the hot water into a bubble state from the bubble jet port 13 and jets the hot water. The solenoid 16 is turned on and off in order to adjust the strength of the bubbles from the bubble jet port 13 in response to a command from the microcomputer in the control box 17. AC power is supplied to the circulation pump 15, the solenoid 16, and the control box 17 via a power supply line 18. The control box 17 is a ceiling outer surface 19 of the bathroom 11.
Is connected to a remote controller 21 which is operated by a bather in the whirlpool 12 via a wiring 20 buried in the bathroom wall. The remote controller 21 is attached to the bathroom wall, and outputs an operation signal to the control box 17 by a hand operation by a bather. The control operation in the control box 17 can control the operation, stop, and the strength of the air bubbles of the jet bath 12.

Referring to FIG. 2, a contact control device according to the present embodiment in the whirlpool controller shown in FIG. 1 will be described. First and second contacts 23 and 24, which are normally open contacts (1a contacts) to a power supply line 18 connecting the AC power supply 22 and the circulation pump 15, and a zero-phase current transformer 25 as an example of a leakage detecting means. , And a current transformer 26 as an example of a current detecting unit is inserted and connected. Both contacts 23 and 24 are 1a contacts (normally open contacts).
The zero-phase current transformer 25 is connected to the leakage detection circuit 27 and the current transformer 2.
6 are connected to the current detection circuit 28, respectively. The leakage detection circuit 27 outputs a low-level leakage detection output S01 when no leakage occurrence output is given from the zero-phase current transformer 23,
When a leakage occurrence output is given, a high-level leakage detection output S01 is output. The current detection circuit 28 outputs a low-level current detection output S02 when no output is given from the current transformer 25, and outputs a high-level current detection output S02 when an output is given.

The control circuit 29 as an example of the control means includes:
A microcomputer having a function of judging contact welding from the detection output S02 of the current detection circuit 28 is built in, and each of the contacts 23 and 24 is alternately and firstly controlled to close drive or alternately and firstly controlled to cancel close drive. First and second drive signals S1, S2 having a relationship as shown in FIG.
2 is output. The first drive signal S1 is a signal for closing the first contact 23, and the second drive signal S2 is a signal for closing the second contact 24.
The output prohibition circuit 30 as an example of the output prohibition means includes a first
, And a second NAND gate 32. The output of the leakage detection circuit 27 is input to one input of each of the NAND gates 31 and 32, and the first and second drive signals S1 and S2 are input to the other input of each of the NAND gates 31 and 32, respectively. Output portions of the two NAND gates 31 and 32 are connected to relay coils 33 and 34 as an example of contact driving means. The control circuit 29 uses the two drive signals S1 and S2 to
The respective contacts 23 and 24 are alternately first closed or alternately released first with respect to each other. This will be described.

(1) When the circulation pump 15 is not driven: When the circulation pump 15 is not driven, the control circuit 29 does not output the drive signals S1 and S2. At this time, if there is no leakage, the leakage detection circuit 27 outputs the low-level non-leakage detection output S01, and both NAND gates 31 and 32 in the output prohibition gate circuit 30 are in the output permission state. Since the drive signals S1 and S2 are not output, the first and second relay coils 33 and 34 are not energized, and the first and second contacts 23 and 24 remain open. Therefore, the AC power supply 22 is not supplied to the circulation pump 15,
The jet bath 12 is in a jet bath non-drive mode in which bubbles are not ejected from the bubble ejection port 13.

When a leakage occurs between the circulation pump 15 and the ground when the circulation pump 15 is not driven, a voltage corresponding to the leakage is supplied to the leakage detection circuit 27 by the zero-phase current transformer 23. From the leakage detection circuit 24
Outputs a high-level leakage detection output S01, whereby both the NAND gates 31 and 32 in the output prohibition gate circuit 30 enter the output prohibition state. Of course, since both the drive signals S1 and S2 from the control circuit 29 are at a low level, the first and second relay coils 33 and 34 are not energized, and the first and second contacts 23 and 24 are open. In this state, the AC power supply 22 is not supplied to the circulation pump 15, and the jet bath 12 remains in the jet bath non-drive mode in which no air bubbles are jetted from the air bubble jet port 13 to the jet bath 12.

(2) When the circulation pump 15 is driven: When the circulation pump 15 is driven, the drive signal S
1, S2 are output. At this time, if there is no leakage, the leakage detection output S01 at a low level is output from the leakage detection circuit 27, and both the NAND gates 31 and 32 in the output prohibition gate circuit 30 are in the output permitted state. Accordingly, the first and second relay coils 33 and 34 are energized in response to the drive signals S1 and S2, and the first and second contacts 23 and 24 are driven according to the timing of the drive signals S1 and S2. When both contacts 23 and 24 are both closed, AC power supply 22 is supplied to circulating pump 15, and bubbles are jetted from jet port 13 to jet bath 12 to enter jet bath driving mode. .

When a leakage occurs between the circulation pump 15 and the ground when the circulation pump 15 is not driven, a voltage corresponding to the leakage is supplied to the leakage detection circuit 27 by the zero-phase current transformer 25. From the leakage detection circuit 27
Provides a high-level leakage detection output S01 to both NAND gates 31 and 32 in the output prohibition gate circuit 30,
The output of both drive signals S1 and S2 is prohibited. Therefore, in this output prohibited state, the first and second relay coils 3
3, 34 are not energized, the first and second contacts 23, 24 are both open, and the AC power
Is shut off.

As described above, in the contact control device according to the present embodiment, both the contacts 23 and 24 are used for both the output control of the circulating pump 15 and the leakage control, so that the number of contacts can be reduced. Since the two contacts 23 and 24 are composed of inexpensive 1a contacts, the cost of the system can be reduced as compared with the related art.

Next, in this embodiment, the two contacts 2
3 and 24 are individually driven by the two relay coils 29 and 32. When the circulating pump 15 is driven at an arbitrary time, the first drive signal S1 is supplied from the control circuit 29 for a time T as shown in FIG. The second drive signal S2 rises and outputs first, and then rises and outputs. The first drive signal S1 falls first, and then the second drive signal S2 falls. Next, when the circulating pump 15 is driven at a time after this arbitrary time, the drive signal S2 is started and output for the time T first, and then the drive signal S1 is started and output, and the drive signal S2 is output first. Then, the drive signal S1 falls.

Therefore, the two contacts 23 and 24 are respectively closed and driven alternately first, and the closed drive is alternately released first, so that only one contact is always driven first as in the conventional case. It is driven on average and the contact life is greatly extended.

In this case, the alternate opening and closing driving of the contacts 23 and 24 alternately includes not only the opening and closing driving of each time but also the opening and closing drive of every several times. The opening / closing drive signal has not only the relationship shown in FIG.
For example, the relationship between the open / close drive signals S1 and S2 may be repeated a plurality of times after the relationship between the open / close drive signals S1 and S2 is repeated a plurality of times.

As described above, by controlling the output timings of the drive signals S1 and S2 for the contacts 23 and 24, respectively, the contacts 23 and 24 can be moved relative to each other.
The closing drive is alternately first released or the first closed drive is alternately released. However, in the present embodiment, if both of the contacts 23 and 24 or one of the contacts is welded, the earth leakage breaker 35 will not operate. Even if an attempt is made to forcibly open-drive the two contacts 23 and 24 in the event of a leakage, the one cannot be forcibly opened because the one contact is welded.

Therefore, in this embodiment, such contact welding can be detected early and reliably.
For example, a case where the second contact 24 is welded will be described. FIG. 3 shows that the second contact 24 is welded.
In the timing chart of FIG. 5, if both contacts 23 and 24 are not welded together at times t0 to t1, the first contact 23 is earlier than the second contact 24 by the first drive signal S1 that has already risen. , But the second drive signal S2 has not risen,
Contact 24 is open. Therefore, at time t
At 0 to t1, the level of the current detection output S02 input from the current detection circuit 28 to the control circuit 29 is low. However, when the second contact 24 is welded, the second contact 24 is in the closed state at times t0 to t1 even if the second drive signal S2 has not risen. Therefore, at times t0 to t1, the contacts 23 and 24 are closed, and the level of the current detection output S02 input from the current detection circuit 28 to the control circuit 29 is high. The control circuit 29 can determine from the timing at which the current detection output S02 at the time t0 to t1 becomes high level that the second contact 24 is welded by the built-in microcomputer. Similarly, from time t2 to t
In 3, if both contacts 23 and 24 are not welded together, the second contact 24 is driven to close before the first contact 23, but the first contact 23 is closed. Not driven and not closed. Therefore, the current detection output S02 input from the current detection circuit 28 to the control circuit 29
Is a low level. However, the first contact 23
Are welded, the first contact 23 is in the closed state even when the first drive signal S1 has not risen between times t2 and t3. Therefore, since both contacts 23 and 24 are in the closed state from time t2 to time t3, the current detection output S input from the current detection circuit 28 to the control circuit 29.
The level of 02 is a high level. The control circuit 29 can determine that the first contact 23 is welded from the timing at which the level of the current detection output S02 at the time t2 to t3 becomes high.

Thus, the control circuit 29 can detect the welding of the contacts 23 and 24 from the timing of the high level or the low level of the detection output S02 from the current detection circuit 28. , 24 can be repaired at an early stage, and in the event of a leak, it is possible to quickly cope with the inability to open and drive both contacts 23, 24 with the earth leakage breaker 35, thereby improving the reliability of the contact control device. Becomes possible.

For example, when the control circuit 29 determines that the contact is welded, it is convenient to drive the display 36 to display the contact weld so that the operator of the system can be notified.

[0027]

As described above, according to the present invention, the inexpensive normally open contact (1a contact) can be used for each of the contacts for the earth leakage cutoff and the output control. There is no need to use expensive normally closed contacts (2b contacts), and the system can be reduced in cost accordingly.
Further, in the present invention, contact welding can be detected at an early stage when a plurality of normally open contacts are used as individually drivable, so that an earth leakage breaker forcibly opens both normally open contacts. In this case, the problem can be solved, and the reliability of the system can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic view of a jet bath controller to which a contact control device according to an embodiment of the present invention is applied.

FIG. 2 is an overall circuit diagram of a contact control system using the contact control device of the present embodiment.

FIG. 3 is a timing chart for explaining the operation of the contact control device according to the embodiment;

FIG. 4 is an overall circuit diagram of a contact control system using a conventional contact control device.

[Explanation of symbols]

 15 Circulation pump 18 Power line 22 AC power supply 23, 24 Normally open contact 25 Zero-phase current transformer 26 Current transformer 27 Leakage detection circuit 28 Current detection circuit 29 Control circuit 30 Output inhibit gate circuit 33, 34 Relay coil

Claims (5)

[Claims] 1. A power supply line between a power supply and a load, wherein a plurality of contacts are provided, and each of the contacts is alternately firstly controlled to close drive or alternately firstly controlled to cancel close drive. A contact control system comprising: detecting an open / close state of a contact; judging an open / close timing of each of the contacts based on the detection; and detecting welding of the contact. 2. A control means for alternately first controlling closing drive or alternately first canceling closing drive of each of a plurality of contacts provided on a power supply line between a power supply and a load; Detecting means for detecting the open / closed state of the contact point, wherein the control means determines the opening / closing timing of each of the contacts based on a detection output of the detecting means and detects welding of the contacts. . 3. The contact control device according to claim 2, further comprising current detection means for detecting a current flowing in the power supply line, wherein the control means determines the opening / closing timing based on a detection output of the current detection means. A contact control device, characterized in that: 4. A plurality of normally open contacts provided on a power supply line between a power supply and a load, a plurality of normally open contacts being controlled alternately first and a plurality of alternately first being controlled to release closed drive. Control means for outputting each of the drive signals; leakage detection means for detecting a leakage in the power supply line; current detection means for detecting a current flowing in the power supply line; and a leakage detection output from the leakage detection means. Output prohibiting means for prohibiting signal output, and a plurality of driving means for individually driving each of the contacts, wherein the control means transmits each of the plurality of driving signals via the output prohibiting means. And outputting the current to each of the plurality of driving means, and detecting the welding state of each of the contacts by determining the timing of the open / close state of each of the contacts based on the detection output of the current. Control device. 5. A load is connected to an AC power supply via a pair of power lines, and a contact is individually provided for each of the pair of power lines.
An apparatus controller, wherein each of the two contacts is driven by the contact control device according to claim 2.