Press double valve detection and protection system and method

Abstract

The present invention provides a press double valve detection and protection system and method, wherein the press double valve includes two-way switches, and the system includes: a detection unit, the detection unit is connected to the two-way switches respectively, the detection unit is used to detect the opening and closing states of the two-way switches within a limited time, and judge whether the two-way switches complete the synchronous action within the limited time according to the opening and closing states, if the two-way switches complete the synchronous action within the limited time, then the corresponding signal is output through the first channel, otherwise the corresponding signal is output through the second channel; an alarm unit and a protection unit, the alarm unit and the protection unit are both connected to the detection unit, and are used to alarm and shut down when the two-way switches fail to complete the synchronous action beyond the limited time. The present invention can timely and effectively judge whether the press double valve is faulty, and alarm and quickly stop the press when the press double valve fails, thereby ensuring the working safety of the press.

Description

Technical Field

[0001] The present invention relates to the technical field of synchronous detection, and in particular to a press double valve detection and protection system and a press double valve detection and protection method. Background Art

[0002] At present, the double valve of the pneumatic press is the core component of the press, specifically the electrical and mechanical related linkage components, which can be used to control all the actions of the press. In normal operation, the two valves of the double valve are synchronized to cooperate with the control of the press, but if the two valves of the double valve are not synchronized during operation, problems will occur whether the press is opened or closed, which may cause safety accidents.

[0003] Therefore, it can be seen that it is extremely important to timely understand the working status of the double valve during the operation of the press, and to stop the press in time when the double valve is not working synchronously. However, at present, when detecting the working status of the double valve, it is usually judged by detecting the air inlet and outlet of the double valve. Not only is the structure of the detection device more complicated, but the action sensitivity is also low. Summary of the invention

[0004] The present invention aims to solve at least one of the technical problems in the above-mentioned technology to a certain extent. To this end, one purpose of the present invention is to provide a press double valve detection and protection system, which can timely and effectively determine whether the press double valve is faulty by detecting whether the two-way switches are synchronized, and alarm and quickly stop the press when the press double valve fails, thereby ensuring the working safety of the press, and at the same time, the system has a simple structure, is easy to install, and has high action sensitivity.

[0005] The second object of the present invention is to provide a press double valve detection and protection method.

[0006] To achieve the above-mentioned purpose, the first aspect of the present invention proposes a press double valve detection and protection system, wherein the press double valve includes two switches, and when the press double valve is actuated, the two switches are driven to act simultaneously through an internal connecting rod device, and the detection and protection system includes: a detection unit, wherein the detection unit is respectively connected to the two switches, and the detection unit is used to detect the opening and closing states of the two switches within a limited time, and judge whether the two switches complete the synchronous action within the limited time according to the opening and closing states, if the two switches complete the synchronous action within the limited time, a corresponding signal is output through a first channel, and if the two switches still fail to complete the synchronous action after exceeding the limited time, a corresponding signal is output through a second channel; an alarm unit, wherein the alarm unit is connected to the detection unit, and the alarm unit is used to alarm when the two switches still fail to complete the synchronous action after exceeding the limited time; and a protection unit, wherein the protection unit is connected to the detection unit, and the protection unit is used to control the press to stop when the two switches still fail to complete the synchronous action after exceeding the limited time.

[0007] According to the press double valve detection and protection system proposed in the embodiment of the present invention, a detection unit is set to connect the two-way switch to detect the open and closed states of the two-way switches within a limited time, and judge whether the two-way switches act synchronously within the limited time according to the open and closed states. If the two-way switches complete the synchronous action within the limited time, the corresponding signal is output through the first channel. If the two-way switches have not completed the synchronous action after the limited time, the corresponding signal is output through the second channel. An alarm unit and a protection unit are respectively connected to the detection unit to alarm and control the press to stop when the two-way switches have not completed the synchronous action after the limited time. Therefore, it is possible to timely and effectively judge whether the double valve of the press is faulty by detecting whether the two-way switches are synchronized, and to alarm and quickly stop the press when the double valve of the press fails, thereby ensuring the working safety of the press. At the same time, the structure is simple, the installation is convenient, and the action sensitivity is high.

[0008] In addition, the press double valve detection and protection system proposed in the above embodiment of the present invention may also have the following additional technical features:

[0009] According to an embodiment of the present invention, the detection unit includes: a decoder, wherein the first and second ports of the decoder are respectively connected to a detection power supply through two switches, the third, sixth and sixteenth ports of the decoder are connected to the detection power supply, and the fourth, fifth and eighth ports of the decoder are all grounded; a capacitor, wherein one end of the capacitor is connected to the detection power supply and the other end of the capacitor is grounded; a first diode, wherein the cathode of the first diode is connected to the twelfth port of the decoder; a second diode, wherein the cathode of the second diode is connected to the thirteenth port of the decoder; a third diode, wherein the cathode of the third diode is connected to the tenth port of the decoder; Four ports are connected; a fourth diode, the cathode of the fourth diode is connected to the fifteenth port of the decoder; a first optocoupler switch, one end of the input side of the first optocoupler switch is connected to the anodes of the second and third diodes respectively; a second optocoupler switch, one end of the input side of the second optocoupler switch is connected to the anodes of the first and fourth diodes respectively; a first resistor, one end of the first resistor is connected to the other end of the input side of the first optocoupler switch, and the other end of the first resistor is connected to the detection power supply; a second resistor, one end of the second resistor is connected to the other end of the input side of the second optocoupler switch, and the other end of the second resistor is connected to the detection power supply.

[0010] Furthermore, the twelfth and fifteenth ports of the decoder constitute the first channel, and the first channel is used to output the corresponding signal generated by the decoder when the two switches complete the synchronization action within a limited time, and the thirteenth and fourteenth ports of the decoder constitute the second channel, and the second channel is used to output the corresponding signal generated by the decoder when the two switches have not completed the synchronization action within a limited time.

[0011] According to one embodiment of the present invention, the limited time is a time threshold for preventing a safety accident from occurring when the double valves of the press machine operate asynchronously.

[0012] According to an embodiment of the present invention, the synchronous action includes synchronous closing and synchronous opening.

[0013] According to one embodiment of the present invention, the alarm unit includes an alarm signal light, a time relay and an intermediate relay, wherein one side of the coil of the time relay is connected to one end of the output side of the first optocoupler switch, the other side of the coil of the time relay is connected to the negative pole of the alarm power supply, the other end of the output side of the first optocoupler switch is connected to the positive pole of the alarm power supply, one end of the contact of the time relay is respectively connected to one side of the coil of the intermediate relay and one end of the alarm signal light, the other end of the contact of the time relay is connected to the positive pole of the alarm power supply, the other side of the coil of the intermediate relay is connected to the negative pole of the alarm power supply, one end of the contact of the intermediate relay is connected to one end of the alarm signal light, the other end of the contact of the intermediate relay is connected to the positive pole of the alarm power supply, and the other end of the alarm signal light is connected to the negative pole of the alarm power supply.

[0014] According to one embodiment of the present invention, the protection unit includes a protection switch, one end of the protection switch is connected to one end of the output side of the second optocoupler switch, the other end of the output side of the second optocoupler switch is connected to a protection power supply, and the other end of the protection switch is connected to the control circuit of the press.

[0015] According to one embodiment of the present invention, the decoder is a 74LS138P decoder.

[0016] To achieve the above-mentioned purpose, the second aspect of the embodiment of the present invention proposes a press double valve detection and protection method, wherein the press double valve includes two switches, and when the press double valve is actuated, the two switches are driven to actuate simultaneously through an internal connecting rod device, and the method includes the following steps: detecting the opening and closing states of the two switches within a limited time; judging whether the two switches complete the synchronous action within the limited time according to the opening and closing states; if the two switches complete the synchronous action within the limited time, outputting a corresponding signal through a first channel; if the two switches still fail to complete the synchronous action within the limited time, outputting a corresponding signal through a second channel, and alarming and controlling the press to stop.

[0017] According to the press double valve detection and protection method proposed in the embodiment of the present invention, by detecting the opening and closing states of the two-way switches within a limited time, it can be determined whether the two-way switches have completed the synchronous action within the limited time based on the opening and closing states. Finally, when the two-way switches complete the synchronous action within the limited time, a corresponding signal can be output through the first channel, and when the two-way switches have not completed the synchronous action after exceeding the limited time, a corresponding signal can be output through the second channel, and an alarm can be issued and the press can be controlled to stop. Therefore, it is possible to timely and effectively determine whether the press double valve is faulty by detecting whether the two-way switches are synchronized, and to issue an alarm and quickly stop the press when the press double valve fails, thereby ensuring the working safety of the press and having high action sensitivity.

[0018] In addition, the press machine double valve detection and protection method proposed in the above embodiment of the present invention may also have the following additional technical features:

[0019] According to one embodiment of the present invention, the limited time is a time threshold for preventing a safety accident from occurring when the double valves of the press machine operate asynchronously. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a block diagram of a press double valve detection and protection system according to an embodiment of the present invention;

[0021] Figure 2 A circuit diagram of a detection unit according to an embodiment of the present invention;

[0022] Figure 3 A pin diagram of a decoder according to an embodiment of the present invention;

[0023] Figure 4 A circuit diagram of an alarm unit according to an embodiment of the present invention;

[0024] Figure 5 A circuit diagram of a protection unit according to an embodiment of the present invention;

[0025] Figure 6 The present invention is a flowchart of a press double valve detection and protection method according to an embodiment of the present invention. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] It should be noted that the press double valve in which the press double valve detection and protection system and method according to the embodiment of the present invention act includes a two-way switch. When the press double valve is actuated, the two-way switches can be driven to actuate simultaneously through an internal connecting rod device, that is, the state of the press double valve can be reflected in real time through the action of the two-way switch. The press double valve detection and protection system and method according to the embodiment of the present invention will be explained below using the AD-SL231D-406D-M2-DD2 press double valve as an example, wherein the two-way switches in the AD-SL231D-406D-M2-DD2 press double valve are two-way micro switches.

[0028] like Figure 1As shown, the press double valve detection and protection system of the embodiment of the present invention includes a detection unit 10, an alarm unit 20 and a protection unit 30. Among them, the detection unit 10 is connected to the two-way switch respectively, and the detection unit 10 is used to detect the opening and closing state of the two-way switch within a limited time, and judge whether the two-way switch completes the synchronous action within the limited time according to the opening and closing state. If the two-way switch completes the synchronous action within the limited time, the corresponding signal is output through the first channel, and if the two-way switch still fails to complete the synchronous action within the limited time, the corresponding signal is output through the second channel; the alarm unit 20 is connected to the detection unit 10, and the alarm unit 20 is used to alarm when the two-way switch still fails to complete the synchronous action within the limited time; the protection unit 30 is connected to the detection unit 10, and the protection unit 30 is used to control the press to stop when the two-way switch still fails to complete the synchronous action within the limited time.

[0029] In one embodiment of the present invention, Figure 2 As shown, the detection unit 10 includes: a decoder, the first and second ports of the decoder, namely, pin 1 and pin 2, can be connected to a detection power supply, namely, a +5V power supply, through two switches respectively, the third, sixth, and sixteenth ports of the decoder, namely, pin 3, pin 6, and pin 16, can be connected to a detection power supply, namely, a +5V power supply, and the fourth, fifth, and eighth ports of the decoder, namely, pin 4, pin 5, and pin 8, are all grounded; a capacitor C1, one end of the capacitor C1 can be connected to a detection power supply, namely, a +5V power supply, and the other end of the capacitor C1 can be grounded; a first diode Q1, the cathode of the first diode Q1 can be connected to the twelfth port of the decoder, namely, pin 12; a second diode Q2, the cathode of the second diode Q2 can be connected to the thirteenth port of the decoder, namely, pin 13; a third diode Q3, the cathode of the third diode Q3 can be connected to The fourteenth port of the decoder is connected to pin No. 14; the fourth diode Q4, the cathode of the fourth diode Q4 can be connected to the fifteenth port of the decoder, that is, pin No. 15; the first optocoupler switch VD1, one end of the input side of the first optocoupler switch VD1 can be connected to the positive electrodes of the second and third diodes, that is, Q2 and Q3 respectively; the second optocoupler switch VD2, one end of the input side of the second optocoupler switch VD2 can be connected to the positive electrodes of the first and fourth diodes, that is, Q1 and Q4 respectively; the first resistor R1, one end of the first resistor R1 can be connected to the other end of the input side of the first optocoupler switch VD1, and the other end of the first resistor R1 can be connected to a detection power supply, that is, a +5V power supply; the second resistor R2, one end of the second resistor R2 can be connected to the other end of the input side of the second optocoupler switch VD2, and the other end of the second resistor R2 can be connected to a detection power supply, that is, a +5V power supply.

[0030] Among them, the decoder can select a decoder of model 74LS138P, whose pin diagram is shown in Figure 3, and whose function truth table is shown in Table 1. Specifically, the 74LS138P decoder can decode according to the binary signals of the input terminals A2, A1, and A0, and can output low-level signals through the corresponding decimal output terminals after decoding. For example, when one strobe terminal, that is, the E1 terminal, is at a high level and the other two strobe terminals, that is, the E2 and E3 terminals, are at a low level, the binary code of the address terminal, that is, A0, A1, and A2, can be decoded at a low level at the output terminals corresponding to Y0 to Y7. For example, when A2A1A0=110, a low level can be output through the Y6 terminal, where "1" is a high level and "0" is a low level.

[0031]

[0032] Table 1

[0033] In one embodiment of the present invention, the twelfth and fifteenth ports of the decoder, i.e., pins 12 and 15, may constitute a first channel, which may output a corresponding signal generated by the decoder, i.e., a normal state signal, when the two switches complete the synchronization action within a limited time; in addition, the thirteenth and fourteenth ports of the decoder, i.e., pins 13 and 14, may constitute a second channel, which may output a corresponding signal generated by the decoder, i.e., an abnormal state signal, when the two switches have not completed the synchronization action within a limited time.

[0034] For example, when two switches complete synchronous actions within a limited time, such as Figure 2 As shown, when the synchronization is disconnected, both pins 1 and 2 of the decoder can maintain a low level, and the corresponding state in the decoder is 000. Further decoding by the decoder can obtain the corresponding low-level output as Y0, that is, pin 15; similarly, when the two switches complete the synchronous action within a limited time, for example, when they are synchronously closed, both pins 1 and 2 of the decoder can maintain a high level, and the corresponding state in the decoder is 011. Further decoding by the decoder can obtain the corresponding high-level output as Y3, that is, pin 12. Pins 12 and 15 of the decoder can be further connected to form a first channel, so as to classify the two switches that complete the synchronous action within a limited time, that is, the normal state, into one category, and at the same time, it can be ensured that the signals generated when the two switches complete the synchronous action within a limited time, that is, the normal state signals, are converted between pins 12 and 15.

[0035] When the two switches have not completed the synchronous action within the specified time, for example, they are not disconnected synchronously, and the micro switch X0 is disconnected first, the pin 1 of the decoder maintains a low level and the pin 2 maintains a high level, and the corresponding state in the decoder is 010. Further decoding by the decoder can obtain the corresponding low-level output as Y2, that is, pin 13; similarly, when the two switches have not completed the synchronous action within the specified time, for example, they are not closed synchronously, and the micro switch X0 is closed first, the pin 1 of the decoder can maintain a high level and the pin 2 can maintain a low level, and the corresponding state in the decoder is 001. Further decoding by the decoder can obtain the corresponding high-level output as Y1, that is, pin 14. Further, the pins 13 and 14 of the decoder can be connected to form a second channel, so that the two switches have not completed the synchronous action within the specified time, that is, the abnormal and normal states are classified into one category, and at the same time, it can be ensured that the signal generated when the two switches have not completed the synchronous action within the specified time, that is, the normal state signal, is converted between pins 13 and 14.

[0036] In one embodiment of the present invention, Figure 4 As shown, the alarm unit may include an alarm signal lamp HL1, a time relay KT and an intermediate relay KA, wherein one side of the coil KT of the time relay KT may be connected to one end of the output side of the first optocoupler switch VD1, the other side of the coil KT of the time relay KT may be connected to the negative pole of the alarm power supply, i.e., the 0V end, the other end of the output side of the first optocoupler switch VD1 is connected to the positive pole of the alarm power supply, i.e., the +24V end, one end of the contact KT of the time relay KT is respectively connected to one side of the coil KA of the intermediate relay KA and one end of the alarm signal lamp HL1, the other end of the contact KT of the time relay KT may be connected to the positive pole of the alarm power supply, i.e., the +24V end, the other side of the coil KA of the intermediate relay KA may be connected to the negative pole of the alarm power supply, i.e., the 0V end, one end of the contact KA of the intermediate relay KA is connected to one end of the alarm signal lamp HL1, the other end of the contact KA of the intermediate relay KA may be connected to the positive pole of the alarm power supply, i.e., the +24V end, and the other end of the alarm signal lamp HL1 may be connected to the negative pole of the alarm power supply, i.e., the 0V end.

[0037] In one embodiment of the present invention, Figure 5 As shown, the protection unit 30 may include a protection switch SB1, one end of the protection switch SB1 is connected to one end of the output side of the second optical coupling switch VD2, the other end of the output side of the second optical coupling switch VD2 is connected to the protection power supply, that is, the +24V end, and the other end of the protection switch SB1 is connected to the control circuit of the press. By connecting the protection switch to the second optical coupling switch, the press can be controlled to stop in an emergency when the detection unit outputs an abnormal state signal.

[0038] based on Figure 4 and Figure 5The circuit shown can set the limit time to 0.3s, that is, the double valve of the press is considered to be in a normal state if it fails to complete the synchronous action within 0.3s. It is considered to be in a fault state if it fails to complete the synchronous action for more than 0.3s. Therefore, when the double valve of the press fails to synchronize, the fault signal output by the first optical coupling switch VD1 can connect the time relay KT. After being screened by the time relay KT and the intermediate relay KA, if the double valve of the press fails to complete the synchronous action for more than 0.3s, the contact KT and the contact KA are closed, so that the alarm signal light HL1 lights up, and at the same time, the second optical coupling switch VD2 is blocked, the emergency stop control circuit of the press is disconnected, and the press stops urgently. If the double valve of the press completes the synchronous action within 0.3s, the press works normally.

[0039] It should be noted that the above-mentioned limited time is the time threshold at which no safety accidents will occur when the press double valve is working in different conditions according to relevant standards. Therefore, in order to avoid unnecessary alarms and emergency stop operations, the fault phenomenon can also be delayed through a delay circuit.

[0040] According to the press double valve detection and protection system proposed in the embodiment of the present invention, a detection unit is set to connect the two-way switch to detect the open and closed states of the two-way switches within a limited time, and judge whether the two-way switches act synchronously within the limited time according to the open and closed states. If the two-way switches complete the synchronous action within the limited time, the corresponding signal is output through the first channel. If the two-way switches have not completed the synchronous action after the limited time, the corresponding signal is output through the second channel. An alarm unit and a protection unit are respectively connected to the detection unit to alarm and control the press to stop when the two-way switches have not completed the synchronous action after the limited time. Therefore, it is possible to timely and effectively judge whether the double valve of the press is faulty by detecting whether the two-way switches are synchronized, and to alarm and quickly stop the press when the double valve of the press fails, thereby ensuring the working safety of the press. At the same time, the structure is simple, the installation is convenient, and the action sensitivity is high.

[0041] Corresponding to the above-mentioned embodiment, the present invention also proposes a press double valve detection and protection method.

[0042] like Figure 6 As shown, the press double valve detection and protection method according to the embodiment of the present invention comprises the following steps:

[0043] S1, detects the open and closed status of the two switches within a limited time.

[0044] S2, judging whether the two switches complete synchronous action within a limited time according to the opening and closing status.

[0045] S3: If the two switches complete the synchronous action within the specified time, the corresponding signal is output through the first channel.

[0046] S4: If the two switches fail to complete the synchronous action within the specified time, the corresponding signal will be output through the second channel, and an alarm will be issued and the press will be controlled to stop.

[0047] In one embodiment of the present invention, the detection unit can detect the open and closed states of the two switches within a limited time, and determine whether the two switches complete the synchronous action within the limited time according to the open and closed states.

[0048] Specifically, Figure 2 As shown, the open and closed states of the two switches within a limited time can be detected through pin 1 and pin 2. When the two switches complete the synchronous action within the limited time, for example, Figure 2 As shown, when the synchronization is disconnected, both pins 1 and 2 of the decoder can maintain a low level, and the corresponding state in the decoder is 000. Further decoding by the decoder can obtain the corresponding low-level output as Y0, that is, pin 15; similarly, when the two switches complete the synchronous action within a limited time, for example, when they are synchronously closed, both pins 1 and 2 of the decoder can maintain a high level, and the corresponding state in the decoder is 011. Further decoding by the decoder can obtain the corresponding high-level output as Y3, that is, pin 12. Pins 12 and 15 of the decoder can be further connected to form a first channel, so as to classify the two switches that complete the synchronous action within a limited time, that is, the normal state, into one category, and at the same time ensure that the signals generated when the two switches complete the synchronous action within a limited time are converted between pins 12 and 15.

[0049] When the two switches have not completed the synchronous action within the specified time, for example, they are not disconnected synchronously, and the micro switch X0 is disconnected first, the pin 1 of the decoder maintains a low level and the pin 2 maintains a high level, and the corresponding state in the decoder is 010. Further decoding by the decoder can obtain the corresponding low-level output as Y2, that is, pin 13; similarly, when the two switches have not completed the synchronous action within the specified time, for example, they are not closed synchronously, and the micro switch X0 is closed first, the pin 1 of the decoder can maintain a high level and the pin 2 can maintain a low level, and the corresponding state in the decoder is 001. Further decoding by the decoder can obtain the corresponding high-level output as Y1, that is, pin 14. Further, the pins 13 and 14 of the decoder can be connected to form a second channel, so that the two switches have not completed the synchronous action within the specified time, that is, the abnormal and normal states are classified into one category, and at the same time, it can be ensured that the signal generated when the two switches have not completed the synchronous action within the specified time, that is, the normal state signal, is converted between pins 13 and 14.

[0050] Furthermore, a first channel can be formed according to pins 12 and 15 of the decoder, and when the two switches complete the synchronous action within a limited time, the corresponding signal generated by the decoder, i.e., a normal output signal, can be output; in addition, a second channel can be formed according to pins 13 and 14 of the decoder, and when the two switches have not completed the synchronous action within a limited time, the corresponding signal generated by the decoder, i.e., an abnormal output signal, can be output.

[0051] In one embodiment of the present invention, an alarm unit may be used to generate an alarm when the two switches fail to complete the synchronization action after a specified time. Figure 4 As shown, the alarm unit may include an alarm signal lamp HL1, a time relay KT and an intermediate relay KA, wherein one side of the coil KT of the time relay KT may be connected to one end of the output side of the first optocoupler switch VD1, the other side of the coil KT of the time relay KT may be connected to the negative pole of the alarm power supply, i.e., the 0V end, the other end of the output side of the first optocoupler switch VD1 is connected to the positive pole of the alarm power supply, i.e., the +24V end, one end of the contact KT of the time relay KT is respectively connected to one side of the coil KA of the intermediate relay KA and one end of the alarm signal lamp HL1, the other end of the contact KT of the time relay KT may be connected to the positive pole of the alarm power supply, i.e., the +24V end, the other side of the coil KA of the intermediate relay KA may be connected to the negative pole of the alarm power supply, i.e., the 0V end, one end of the contact KA of the intermediate relay KA is connected to one end of the alarm signal lamp HL1, the other end of the contact KA of the intermediate relay KA may be connected to the positive pole of the alarm power supply, i.e., the +24V end, and the other end of the alarm signal lamp HL1 may be connected to the negative pole of the alarm power supply, i.e., the 0V end.

[0052] In one embodiment of the present invention, the protection unit can be used to control the press to stop urgently when the two switches fail to complete the synchronous action within a specified time. Figure 5 As shown, the protection unit can be a protection switch SB1, one end of the protection switch SB1 is connected to one end of the output side of the second optocoupler switch VD2, the other end of the output side of the second optocoupler switch VD2 is connected to the protection power supply, that is, the +24V end, and the other end of the protection switch SB1 is connected to the control circuit of the press.

[0053] based on Figure 4 and Figure 5The circuit shown can set the limit time to 0.3s, that is, the double valve of the press is considered to be in a normal state if it fails to complete the synchronous action within 0.3s. It is considered to be in a fault state if it fails to complete the synchronous action for more than 0.3s. Therefore, when the double valve of the press fails to synchronize, the fault signal output by the first optical coupling switch VD1 can connect the time relay KT. After being screened by the time relay KT and the intermediate relay KA, if the double valve of the press fails to complete the synchronous action for more than 0.3s, the contact KT and the contact KA are closed, so that the alarm signal light HL1 lights up, and at the same time, the second optical coupling switch VD2 is blocked, the emergency stop control circuit of the press is disconnected, and the press stops urgently. If the double valve of the press completes the synchronous action within 0.3s, the press works normally.

[0054] It should be noted that the above-mentioned limited time is the time threshold at which no safety accidents will occur when the press double valve is working in different conditions according to relevant standards. Therefore, in order to avoid unnecessary alarms and emergency stop operations, the fault phenomenon can also be delayed through a delay circuit.

[0055] According to the press double valve detection and protection method proposed in the embodiment of the present invention, by detecting the opening and closing states of the two-way switches within a limited time, it can be determined whether the two-way switches have completed the synchronous action within the limited time based on the opening and closing states. Finally, when the two-way switches complete the synchronous action within the limited time, a corresponding signal can be output through the first channel, and when the two-way switches have not completed the synchronous action after exceeding the limited time, a corresponding signal can be output through the second channel, and an alarm can be issued and the press can be controlled to stop. Therefore, it is possible to timely and effectively determine whether the press double valve is faulty by detecting whether the two-way switches are synchronized, and to issue an alarm and quickly stop the press when the press double valve fails, thereby ensuring the working safety of the press and having high action sensitivity.

[0056] In the present invention, unless otherwise clearly specified and limited, the term "connected" should be understood in a broad sense, for example, it can be fixedly connected, detachably connected, or integrated; it can be mechanically connected or electrically connected; it can be directly connected or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0057] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0058] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0059] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A double valve detection and protection system for a press machine, characterized in that: The press double valve includes two switches. When the press double valve is actuated, the two switches are driven to actuate simultaneously through an internal connecting rod device. The detection and protection system includes: A detection unit, the detection unit is connected to the two switches respectively, the detection unit is used to detect the open and closed states of the two switches within a limited time, and judge whether the two switches have completed the synchronous action within the limited time according to the open and closed states, if the two switches have completed the synchronous action within the limited time, then the corresponding signal is output through the first channel, if the two switches have not completed the synchronous action after the limited time, then the corresponding signal is output through the second channel; An alarm unit, the alarm unit is connected to the detection unit, and the alarm unit is used to alarm when the two switches have not completed the synchronous action within a limited time; A protection unit, the protection unit is connected to the detection unit, and the protection unit is used to control the press to stop when the two switches have not completed the synchronous action within a limited time. The detection unit comprises: A decoder, wherein the first and second ports of the decoder are respectively connected to a detection power supply through two micro switches, the third, sixth and sixteenth ports of the decoder are connected to the detection power supply, and the fourth, fifth and eighth ports of the decoder are all grounded; A capacitor, one end of which is connected to the detection power supply, and the other end of which is grounded; a first diode, wherein a cathode of the first diode is connected to the twelfth port of the decoder; a second diode, wherein a cathode of the second diode is connected to the thirteenth port of the decoder; a third diode, wherein a cathode of the third diode is connected to the fourteenth port of the decoder; a fourth diode, wherein a cathode of the fourth diode is connected to the fifteenth port of the decoder; a first optical coupler switch, wherein one end of the input side of the first optical coupler switch is connected to the anodes of the second diode and the third diode respectively; a second optical coupler switch, wherein one end of the input side of the second optical coupler switch is connected to the anodes of the first diode and the fourth diode respectively; a first resistor, one end of the first resistor being connected to the other end of the input side of the first optical coupler switch, and the other end of the first resistor being connected to the detection power supply; A second resistor, one end of the second resistor is connected to the other end of the input side of the second optical coupler switch, and the other end of the second resistor is connected to the detection power supply.

2. The press double valve detection and protection system according to claim 1 is characterized in that: in, The twelfth and fifteenth ports of the decoder constitute the first channel, and the first channel is used to output the corresponding signal generated by the decoder when the two switches complete the synchronization action within a limited time. The thirteenth and fourteenth ports of the decoder constitute the second channel, and the second channel is used to output the corresponding signal generated by the decoder when the two switches have not completed the synchronization action within a limited time.

3. The press double valve detection and protection system according to claim 2 is characterized in that: The limited time is a time threshold for preventing safety accidents from occurring when the double valves of the press machine operate asynchronously.

4. The press double valve detection and protection system according to claim 3 is characterized in that: The synchronous action includes synchronous closing and synchronous opening.

5. The press double valve detection and protection system according to claim 4 is characterized in that: The alarm unit includes an alarm signal light, a time relay and an intermediate relay, wherein one side of the coil of the time relay is connected to one end of the output side of the first optocoupler switch, the other side of the coil of the time relay is connected to the negative pole of the alarm power supply, the other end of the output side of the first optocoupler switch is connected to the positive pole of the alarm power supply, one end of the contact of the time relay is respectively connected to one side of the coil of the intermediate relay and one end of the alarm signal light, the other end of the contact of the time relay is connected to the positive pole of the alarm power supply, the other side of the coil of the intermediate relay is connected to the negative pole of the alarm power supply, one end of the contact of the intermediate relay is connected to one end of the alarm signal light, the other end of the contact of the intermediate relay is connected to the positive pole of the alarm power supply, and the other end of the alarm signal light is connected to the negative pole of the alarm power supply.

6. The press machine double valve detection and protection system according to claim 5, characterized in that: The protection unit includes a protection switch, one end of the protection switch is connected to one end of the output side of the second optocoupler switch, the other end of the output side of the second optocoupler switch is connected to a protection power supply, and the other end of the protection switch is connected to the control circuit of the press.

7. The press double valve detection and protection system according to claim 6 is characterized in that: The decoder selected is a decoder of model 74LS138P.

8. A press double valve detection and protection method applied to the press double valve detection and protection system according to claim 1, wherein the press double valve comprises two switches, and when the press double valve is actuated, the two switches are driven to actuate simultaneously through an internal connecting rod device, and the method comprises the following steps: Detecting the open and closed states of the two switches within a limited time; Judging whether the two switches complete synchronous action within a limited time according to the open and closed states; If the two switches complete synchronous action within a limited time, a corresponding signal is output through the first channel; If the two switches fail to complete the synchronous action within the specified time, the corresponding signal is output through the second channel, and an alarm is issued and the press is controlled to stop.

9. The press machine double valve detection and protection method according to claim 8, characterized in that: The limited time is a time threshold for preventing safety accidents from occurring when the double valves of the press machine operate asynchronously.

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