Protection circuit of metal filing annunciator

Abstract

The invention discloses a protection circuit of a metal filing annunciator, relates to an annunciator sensor protection circuit, and aims to solve the problems of poor safety and poor reliability caused by high probability of short circuit of the conventional metal filing annunciator. A first signal terminal is connected with one end of a first resistor; the second signal terminal is connected with one end of the second resistor and the negative electrode of the metal filing annunciator body at the same time. And the third signal terminal is simultaneously connected with the other end of the second resistor, the other end of the first resistor and the positive electrode of the metal filing annunciator body. The metal filing annunciator has the beneficial effect that the safety and reliability of the metal filing annunciator are improved.

Description

Technical Field

[0001] The invention relates to a protection circuit for an annunciator sensor. Background Art

[0002] Metal chip detectors are sensors used to detect metal wear particles in mechanical equipment, and they play an important role in the industrial and aviation fields. This sensor can monitor the wear status of the equipment in real time, and send out a signal when the particles generated by wear cause the two ends of the electrode to connect, thereby preventing failures and accidents. In addition, when a failure occurs, the wear particles can be directly disassembled and sampled under power, and the metal chip detector can be cleaned and reinstalled.

[0003] However, the existing metal chip signaler usually contains two electrodes, which are externally led to two signal terminals, one of which is connected to the signal detection device, and the other is connected to the negative end of the power supply. In some products, this end is also the shell of the metal chip signaler. This circuit design is prone to short circuit due to contact with the metal outer wall or other conductive objects during on-site live disassembly and inspection. The short circuit may cause damage to the metal chip signaler or even cause equipment failure and shutdown. Therefore, it is urgent to improve the design of the metal chip signaler circuit to make it safer and more reliable. Summary of the invention

[0004] The purpose of the present invention is to solve the problem that the existing metal chip signal device is prone to short circuit, resulting in poor safety and poor reliability, and a protection circuit for the metal chip signal device is proposed.

[0005] The protection circuit of a metal chip signal device of the present invention comprises a first signal terminal, a second signal terminal, a third signal terminal, a first resistor and a second resistor;

[0006] The signal terminal No. 1 is connected to one end of the resistor No. 1;

[0007] The second signal terminal is respectively connected to one end of the second resistor and the negative electrode of the metal chip signal device body;

[0008] The third signal terminal is respectively connected to the other end of the second resistor, the other end of the first resistor and the positive electrode of the metal chip signal device body.

[0009] Furthermore, the protection circuit also includes a first sliding resistor;

[0010] The first sliding rheostat is connected in parallel at both ends of resistor No. 1.

[0011] Furthermore, the protection circuit also includes a second sliding resistor;

[0012] The second sliding rheostat is connected in parallel to both ends of the second resistor.

[0013] Furthermore, the resistance value of the first resistor is 1 kΩ; the resistance value of the second resistor is 2 kΩ.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] The present invention simply changes the existing metal chip signaler circuit, adds two resistors and a signal terminal, effectively avoids the problem of short circuit damage caused by the metal chip signaler during disassembly and inspection, and even causes the failure and shutdown of related equipment, thereby improving the safety and reliability of the metal chip signaler. At the same time, the improved metal chip signaler circuit provides two forms of switch signal and resistance value signal at the same time, both of which can be used for metal chip signal detection, and can be adapted to different types of external signal detection equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is the circuit diagram of the existing metal chip signal device in the specific implementation mode 1;

[0017] Figure 2 A protection circuit diagram of a metal chip signal device according to the first embodiment;

[0018] Figure 3 The circuit diagram of a metal chip signal protection circuit used in a switch signal detection device according to the first embodiment; wherein a is a wiring diagram with the switch signal detection device 7; b is an equivalent circuit diagram when metal chips are detected; and c is an equivalent circuit diagram when metal chips are not detected;

[0019] Figure 4 The circuit diagram of a metal chip signal protection circuit used in a resistance signal detection device according to the first embodiment; wherein a is a wiring diagram with the resistance signal detection device 8; b is an equivalent circuit diagram when metal chips are detected; and c is an equivalent circuit diagram when metal chips are not detected;

[0020] Figure 5 A protective circuit for a metal chip signal device in a second specific implementation mode;

[0021] Figure 6 This is a protection circuit diagram of a metal chip signal device in a third specific implementation mode. DETAILED DESCRIPTION

[0022] Specific implementation method 1. Combination Figures 1 to 4 The present embodiment is described as a protection circuit of a metal chip signaler in the present embodiment, the protection circuit comprises a first signal terminal 1, a second signal terminal 2, a third signal terminal 4, a first resistor 5 and a second resistor 6;

[0023] The signal terminal No. 1 is connected to one end of the resistor No. 5;

[0024] The second signal terminal 2 is respectively connected to one end of the second resistor 6 and the negative electrode of the metal chip signal device body 3;

[0025] The third signal terminal 4 is connected to the other end of the second resistor 6 , the other end of the first resistor 5 and the positive electrode of the metal chip signal device body 3 respectively.

[0026] In this embodiment, the existing metal chip signal circuit diagram is as follows Figure 1 As shown, the positive electrode of the metal chip signaler body 3 is connected to the first signal terminal 1; the negative electrode of the metal chip signaler body 3 is connected to the second signal terminal 2; by adding two resistors (the first resistor 5 and the second resistor 6) and a third signal terminal 4 on the basis of the existing metal chip signaler circuit, the original two signal terminals (the first signal terminal 1 and the second signal terminal 2) are changed to three signal terminals, forming a metal chip signaler protection circuit described in this embodiment. The specific structure of the metal chip signaler protection circuit is as follows Figure 2 shown.

[0027] The improved protection circuit described in this embodiment can not only provide switch signal detection, but also can be used for resistance value signal detection. Both forms have the safety protection function of preventing short circuit; in the switch signal detection mode, the circuit is designed to be a normally closed mode, that is, when no metal chip signal is detected, there is a high-level signal between signal terminal No. 3 4 and signal terminal No. 2, and when a metal chip signal is detected, there is a low-level signal between signal terminal No. 3 4 and signal terminal No. 2; in the resistance value signal detection mode, the resistance value between signal terminal No. 1 1 and signal terminal No. 2 2 is detected to determine whether there is a metal chip signal.

[0028] The two resistors are used to prevent a short circuit between the third signal terminal 4 and the second signal terminal 2 and to prevent a short circuit between the first signal terminal 1 and the second signal terminal 2 respectively.

[0029] In this embodiment, the metal chip signal device body 3 is used as a metal chip collection device; when the protection circuit is used for switch signal detection:

[0030] Signal terminal No. 1, signal terminal No. 2, and signal terminal No. 3 are used to transmit the switch signal detected by the metal chip signal detector to the positive power supply terminal, the negative power supply terminal, and the signal detection terminal of the switch signal detection device 7. The switch signal detection device 7 can be a switch signal detection module of a PLC;

[0031] The first resistor 5 and the second resistor 6 are used to realize the safety protection function of preventing short circuit.

[0032] The protection circuit described in this embodiment is designed to be in a normally closed mode, that is, when no metal chip signal is detected, a high-level signal is between signal terminal No. 3 4 and signal terminal No. 2 (the signal level depends on the power supply voltage value and the selection of the resistance values ​​of resistor No. 1 5 and resistor No. 2 6), and when a metal chip signal is detected, a low-level signal is between signal terminal No. 3 4 and signal terminal No. 2 2.

[0033] When the metal chip signaler is disassembled and assembled, if the upper end of the metal chip signaler body 3 touches a conductive object, the existence of the first resistor 5 prevents a short circuit from occurring. At this time, a low level signal is present between the third signal terminal 4 and the second signal terminal 2, indicating that a metal chip signal is detected.

[0034] When the metal chip signal is disassembled, if the lower end of the metal chip signal body 3 touches a conductive object, the second signal terminal 2 itself is the negative end of the power supply, and this contact has no effect on the metal chip signal. Figure 3 shown.

[0035] When used for resistance value detection:

[0036] The first signal terminal 1 and the second signal terminal 2 are used to transmit the resistance signal detected by the metal chip signal device to the resistance signal detection device 8 for measurement, and then used to determine whether metal chips are detected.

[0037] The first resistor 5 and the second resistor 6 are used to realize the safety protection function of preventing short circuit in the present invention.

[0038] When no metal chip signal is detected, the resistance between the first signal terminal 1 and the second signal terminal 2 is the sum of the resistance values ​​of the first resistor 5 and the second resistor 6 .

[0039] When the metal chip signal is detected, the resistance between the first signal terminal 1 and the second signal terminal 2 is the resistance of the first resistor 5 .

[0040] Therefore, by detecting the resistance between the first signal terminal 1 and the second signal terminal 2, it can be determined whether the metal chip signal device body 3 detects the metal chip signal; Figure 4 shown.

[0041] For example, when the power supply is DC24V, the resistance of resistor 5 is 1kΩ, and the resistance of resistor 6 is 2kΩ, then the voltage between signal terminals 4 and 2 is about 16V when the voltage is high.

[0042] Specific implementation method 2: Combination Figure 5 This embodiment is described. This embodiment further defines the protection circuit of the metal chip signal device described in the first embodiment. In this embodiment, the protection circuit further includes a first sliding resistor 9.

[0043] The first sliding resistor 9 is connected in parallel to both ends of the resistor No. 1 5 .

[0044] In this embodiment, by adding a first sliding rheostat 9, when adjusting the slider of the first sliding rheostat 9, its output signal voltage and output resistance value can be adjusted to adapt to different types of external signal detection devices (switch signal detection device 7 or resistance signal detection device 8).

[0045] Specific implementation method 3: Combination Figure 6 This embodiment is described. This embodiment further defines the protection circuit of the metal chip signal device described in the first embodiment. In this embodiment, the protection circuit further includes a second sliding resistor 10.

[0046] The second sliding resistor 10 is connected in parallel to both ends of the second resistor 6 .

[0047] In this embodiment, by adding a second sliding rheostat 10, when adjusting the slider of the second sliding rheostat 10, its output signal voltage and output resistance value can be adjusted to adapt to different types of external signal detection devices (switch signal detection device 7 or resistance signal detection device 8).

[0048] Specific implementation method 4: This implementation method further limits the protection circuit of the metal chip signal device described in specific implementation method 1. In this implementation method, the resistance value of the first resistor 5 is 1 kΩ; the resistance value of the second resistor 6 is 2 kΩ.

[0049] In this embodiment, when the resistance value of resistor No. 1 5 is 1kΩ and the resistance value of resistor No. 2 6 is 2kΩ, when metal chips are detected or the upper part of the metal chip signal device body 3 contacts a conductive object, the resistance value between signal terminal No. 3 4 and signal terminal No. 2 2 is the resistance value of resistor No. 1 5, i.e. 1kΩ; when metal chips are not detected or the lower part of the metal chip signal device body 3 contacts a conductive object, the resistance value between signal terminal No. 3 4 and signal terminal No. 2 2 is the sum of the resistance values ​​of resistor No. 1 5 and resistor No. 2 6, i.e. 3kΩ.

[0050] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A protection circuit for a metal chip signaler, the protection circuit comprising a first signal terminal (1) and a second signal terminal (2); characterized in that: It also includes a No. 3 signal terminal (4), a No. 1 resistor (5) and a No. 2 resistor (6); The signal terminal No. 1 (1) is connected to one end of a resistor No. 1 (5); The second signal terminal (2) is respectively connected to one end of the second resistor (6) and the negative electrode of the metal chip signal device body (3); The third signal terminal (4) is respectively connected to the other end of the second resistor (6), the other end of the first resistor (5) and the positive electrode of the metal chip signal device body (3).

2. A metal chip signal protection circuit according to claim 1, characterized in that: The protection circuit also includes a first sliding resistor (9); The first sliding rheostat (9) is connected in parallel to both ends of the No. 1 resistor (5).

3. The protective circuit of the metal chip signal device according to claim 1, characterized in that: The protection circuit also includes a second sliding resistor (10); The second sliding rheostat (10) is connected in parallel to both ends of the second resistor (6).

4. The protective circuit of a metal chip signal device according to claim 1, characterized in that: The resistance value of the No. 1 resistor (5) is 1 kΩ; the resistance value of the No. 2 resistor (6) is 2 kΩ.

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