JP2512101Y2 - High frequency contact open / close state detection device - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for detecting the open / closed state of relay contacts for sequence control or the like.

[0002]

2. Description of the Related Art In sequence control or the like constituted by relay contacts, it is very important to immediately detect the operating condition of the contacts in order to grasp the control condition.

200 relay contacts to detect the open / closed state
When a commercial AC voltage or DC voltage of V to 100 V is applied, conventionally, the operating state of the contact has been determined by the following method. 1. Determine the contact operating state by looking at the appearance of the relay. 2. Measure the voltage or resistance value with a tester or the like to determine the contact operating state.

[0004]

The conventional method of determining the operating state of the relay contact in the sequence control or the like is manual and is difficult to automate. For automatic detection, the detection power source must not affect the relay circuit because it must not affect the relay to be detected and activate it. In addition, it is necessary that a commercial AC voltage or a DC voltage of 200V or 100V does not enter the detection device, or the detection device is not affected by the entry of the voltage.

Therefore, according to the present invention, the open / closed state of a relay contact to which a relatively high voltage of alternating current or direct current is applied has no influence on the high voltage applied state of the relay circuit or affects the operating state of the relay. It is an object of the present invention to provide a detection device that can automatically detect a signal.

[0006]

In order to achieve the above object,
As a result of earnest studies by the present inventors, in order to detect the open / closed state, a high frequency voltage is applied to the contact in addition to the AC or DC voltage applied to the relay, and the presence or absence of the high frequency high frequency voltage is detected. The inventors have found that the open / closed state of a contact can be automatically determined, and have completed the present invention.

That is, the present invention is an apparatus for detecting an open / closed state of a relay contact of a relay circuit in which an AC or DC power supply, a relay contact, and an operating device operated by the power supply are connected in series. A high-frequency generator for applying a high-frequency voltage to both ends of the relay contact via
A high frequency detection device for detecting a high frequency voltage applied to both ends of the relay contact is provided, and a first division resistor and a second division resistor are connected in series between both output ends of the high frequency generation device, and the second division resistor is connected in series. Both ends of the dividing resistor are connected to both ends of the relay contact through at least one blocking capacitor, and the high-frequency detecting device is arranged so that the high frequency detecting device has both ends of the second dividing resistor, or one end of the second dividing resistor and an intermediate portion thereof or A gist of a high-frequency contact open / close state detection device, which is a high-frequency voltage detection device in which an input terminal is connected to two points of an intermediate portion of the second divided resistor.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a block circuit diagram of an example of a high-frequency contact open / close state detecting device in which a conventional known circuit is slightly modified. 1 is a power supply for operating the relay, and as shown in the figure,
It may be a commercial AC power supply of 00V or 200V, 50 or 60Hz, or a DC power supply. Reference numeral 2 is a relay contact whose open / closed state should be detected, and 3 is an operating device such as a relay coil of another relay whose energization is controlled by opening / closing the relay contact 2.

Reference numeral 4 is a contact open / close state detecting device, which comprises a high frequency generator 5, a high frequency current detector 6 and blocking capacitors 7 and 8. One output end 9 of the high frequency generator 5
Is a contact opening / closing state detection device 4 via a blocking capacitor 7.
One of the detectors is connected to the input terminal 10. Further, one input end 11 of the high frequency current detection device 6 is connected to the other detection device input end 1 of the contact opening / closing state detection device 4 via the blocking capacitor 8.
Connect to 2. Further, the other output terminal 13 of the high frequency generator 5
And the other input end 14 of the high-frequency current detection device 6 are connected to form a common base line. The two detector input terminals 10 and 12 of the contact open / closed state detector 4 are connected to both ends of the relay contact 2 whose open / closed state is to be detected.

The high frequency voltage detector 18 has an input terminal 1
A high-frequency current flowing between 1 and 14 is detected, and the open / closed state of the relay contact 2 is displayed according to the presence or absence of the current, or a detection signal is output from the detection device output terminal 15.

FIG. 2 is a block circuit diagram of an example of the high-frequency contact opening / closing state detecting device of the present invention. Similar to FIG. 1, 1 is a power source for relay operation, 2 is a relay contact whose open / closed state should be detected, 3 is an operating device such as a relay coil of another relay whose energization is controlled by opening / closing the relay contact 2. Reference numeral 4 denotes a contact open / close state detecting device of the present invention, which comprises a high frequency generator 5, a high frequency voltage detecting device 18, a blocking capacitor 7, a first dividing resistor 19 and a second dividing resistor 20. Two dividing resistors 19 and 20 are connected in series between the output terminals 9 and 13 of the high frequency generator 5, and the dividing resistors 19 and 20 are connected in series.
The connection point of 20 is connected to one detection device input end 10 of the contact opening / closing state detection device 4 via the blocking capacitor 7. Further, the connection point of the dividing resistors 19 and 20 or the intermediate portion of the second dividing resistor 20 is connected to one input terminal 11 of the high frequency voltage detecting device 18. The second dividing resistor 20 may be a fixed resistor or a variable resistor as shown in FIG. An output end 13 of the high frequency generator 5 coupled to one end of the second dividing resistor 20 is connected to an input end 14 of the high frequency voltage detector 18 and the other detector input end 12 of the contact open / closed state detector 4 to form a common base line. . The input end 14 of the high frequency voltage detecting device 18 is not directly connected to the output end 13 of the high frequency generating device 5,
You may connect to the part apart from the connection part of the input end 11 in the intermediate part of a 2nd division resistance. The two detector input terminals 10 and 12 of the contact open / closed state detector 4 are connected to both ends of the relay contact 2 whose open / closed state is to be detected.

The high frequency detector 6 has its input terminals 11, 14
A high-frequency voltage applied between them is detected, and the open / closed state of the relay contact 2 is displayed or a detection signal is output from the detection device output end 15 according to the presence or absence of the voltage.

The frequency and the voltage of the high frequency applied by the high frequency generator 5 shown in FIGS. 1 and 2 are not particularly limited, but the frequency and the voltage within a range that does not affect the other peripheral devices such as a propagation obstacle. Is selected. For example 5-20
A high frequency of KHz is preferably used, and a frequency of 8 to 12 KHz is more preferably used. The high frequency voltage applied is preferably 50 V or less.

[0014]

In order to detect the open / closed state of the relay contact 2 using the high frequency contact open / closed state detecting device shown in FIG. 1, a high frequency voltage from the high frequency generating device 5 of the contact open / closed state detecting device 4 is passed through a capacitor 7. When the voltage is applied to one terminal 16 of the relay contact 2 and connected from the other terminal 17 of the relay contact 2 to the input terminal 11 of the high frequency current detection device 6 via the blocking capacitor 8, the high frequency is applied when the relay contact 2 is closed. A high frequency current flows between the input ends 11 and 14 of the current detection device 6. When the relay contact 2 is open, no high frequency current flows through the high frequency current detecting device 6. The high-frequency current detection device 6 displays the open / closed state of the relay contact 2 on its display device according to the presence / absence of a high-frequency current flowing between its input ends 11 and 14, and outputs a detection signal to the detection device output end 15.

When the open / closed state of the relay contact 2 is detected, the high voltage of the commercial power source or the DC power source applied to the relay contact 2 is blocked by the blocking capacitors 7 and 8 to detect the high frequency generator 5 and the high frequency current. It is not applied to the device 6.

In order to detect the open / closed state of the relay contact 2 using the high frequency contact open / close state detecting device of the present invention shown in FIG. 2, the high frequency output voltage of the high frequency generator 5 of the contact open / close state detecting device 4 is divided into resistors. Since it is divided by 19 and 20, and both ends of the second dividing resistor 20 are directly connected to both ends of the relay contact 2 via the blocking capacitor 7, respectively, when the relay contact 2 is open, The high frequency output voltage of the high frequency generator 5 is at both ends of the dividing resistor 1
The voltage divided by 9 and 20 is applied, and the corresponding high frequency voltage is applied between the input terminals 11 and 14 of the high frequency voltage detection device 18.

When the relay contact 2 is closed, the high frequency voltage of the second dividing resistor 20 is short-circuited through the blocking capacitor 7 and the relay contact 2, so that the high frequency voltage applied to both ends of the second dividing resistor 20 becomes 0, High frequency voltage detector 18
The high-frequency voltage applied between the input terminals 11 and 14 of is 0.

The high frequency voltage detector 18 has an input terminal 1
The open / close state of the relay contact 2 is displayed on the display device according to the presence / absence of the high-frequency voltage applied between 1 and 14, and a detection signal is output to the detection device output terminal 15.

When the open / closed state of the relay contact 2 is detected, the high voltage of the commercial power source or the DC power source applied to the relay contact 2 is blocked by the blocking capacitor 7 and does not flow into the contact open / closed state detecting device 4. .

According to the high-frequency contact opening / closing state detecting device of the present invention shown in FIG. 2, the high-frequency voltage applied to the relay contact 2 for detecting the contact opening / closing state is higher than that of the operating device 3. Since the high frequency power supply is low and does not form a closed loop connected to the operating device 3, it does not affect the operation of the operating device 3 at all, and the relay circuit is affected by detecting the open / closed state of the relay contact 2. Never give.

In the method for detecting the presence / absence of high-frequency current flowing through both ends of the relay contact 2 shown in FIG. 1, if the connection between the contact opening / closing state detecting device 4 and the relay contact 2 becomes long, even if the relay contact 2 is open. Although there is a risk that a high frequency current will flow due to the electrostatic capacitance of a long connection to cause a malfunction, the method for detecting the presence or absence of a high frequency voltage applied to both ends of the relay contact 2 shown in FIG. Even if the connection with the contact 2 is long, there is no risk of malfunction due to the capacitance of the long connection, and there is an advantage that the connection can be extended.

[0022]

According to the high frequency contact open / closed state detection device of the present invention, it is possible to automatically detect the open / closed state of the relay contact, and the detection signal can easily cope with abnormal operation in sequence control or the like. Become.

During the detection, the relay circuit is not affected at all, and a high AC or DC voltage flowing through the relay circuit is not applied to the detection device, so that the detection can be performed safely.

[Brief description of drawings]

FIG. 1 is a block circuit diagram of an example in which a conventional high-frequency contact open / closed state detection device is slightly modified.

FIG. 2 is a block circuit diagram of another example of the high-frequency contact opening / closing state detecting device of the present invention.

[Explanation of symbols]

 1 power supply 2 relay contact 3 actuating device 4 contact open / closed state detection device 5 high frequency generator 6 high frequency current detection device 7 blocking capacitor 8 blocking capacitor 9 output end 10 detection device input end 11 input end 12 detection device input end 13 output end 14 input Terminal 15 Detection device output terminal 16 Terminal 17 Terminal 18 High frequency voltage detection device 19 Dividing resistor 20 Dividing resistor

Claims (1)

(57) [Scope of utility model registration request] 1. An apparatus for detecting an open / closed state of a relay contact of a relay circuit in which an AC or DC power source, a relay contact, and an operating device operated by the power source are connected in series, through a blocking capacitor. A high-frequency generator for applying a high-frequency voltage to both ends of the relay contact and a high-frequency detector for detecting a high-frequency voltage applied to both ends of the relay contact , the first division being provided between both output ends of the high-frequency generator.
A resistor and a second dividing resistor are connected in series, and the second dividing resistor is connected.
Via at least one blocking capacitor across the anti
The high-frequency detection device is connected to both ends of the relay contact.
Is either end of the second divisional resistor or the second divisional resistor.
At one end and its middle part or the middle part of the second dividing resistor
A high-frequency contact open / close state detection device, which is a high-frequency voltage detection device having an input terminal connected to the .