A durability test system for NTC products

Abstract

The present invention relates to the field of NTC testing, and particularly to a durability testing system for NTC products. The present invention discloses a durability testing system for NTC products, which includes a power supply, a testing device, and a resistance box. The power supply, the testing device, and the resistance box are electrically connected in sequence to form a testing circuit. The testing device is used to install the NTC product to be tested so that the NTC product to be tested is connected into the testing circuit. A load resistance unit is provided in the resistance box for providing the load resistance in the testing circuit. A toggle switch is provided on the resistance box for adjusting the value of the load resistance unit. The present invention can achieve the durability testing of NTC products, and the adjustment of the load resistance size is convenient, fast, with high adjustment accuracy, high safety, and a compact and simple structure.

Description

Technical Field

[0001] The present invention belongs to the field of NTC testing, and particularly relates to a durability testing system for NTC products. Background Art

[0002] An NTC (Negative Temperature Coefficient) thermistor refers to a thermistor whose resistance decreases exponentially with the increase of temperature and has a negative temperature coefficient. Using this characteristic, temperature measurement, temperature compensation, and temperature control components can be made, and power components can also be made to suppress the inrush current of the circuit, etc.

[0003] The testing of NTC products includes type experiments and UL certification experiments, and the UL certification experiments include durability tests. When conducting the durability test of NTC products, a load resistor and a capacitor are provided in the test circuit. The load resistor is used to simulate the impedance of the load, and the capacitor is used to simulate the capacitive reactance of the load. To facilitate the adjustment of the test current magnitude, the resistance value of the load resistor needs to be adjustable. The existing load resistors with adjustable resistance values are all realized by using sliding rheostats, and their disadvantages are: low adjustment accuracy, and sometimes it is necessary to repeatedly slide back and forth for fine adjustment to adjust to the required resistance value, which is inconvenient and slow to adjust, and has low safety.

[0004] In addition, the existing test devices for conducting the durability test of NTC products are all built on the workbench. The entire test device has a messy circuit, low test safety, and the test effect is also easily interfered. Summary of the Invention

[0005] The purpose of the present invention is to provide a durability testing system for NTC products to solve the above existing technical problems.

[0006] To achieve the above purpose, the technical solution adopted by the present invention is: a durability testing system for NTC products, including a power supply, a test device, and a resistance box. The power supply, the test device, and the resistance box are electrically connected in sequence to form a test circuit. The test device is used to install the NTC product to be tested so that the NTC product to be tested is connected into the test circuit. The resistance box is provided with a load resistor unit for providing the load resistor in the test circuit, and the resistance box is provided with a toggle switch for adjusting the resistance value of the load resistor unit.

[0007] Further, the load resistor unit includes a plurality of sub-load resistors. The number of toggle switches is the same as the number of sub-load resistors. The plurality of sub-load resistors are respectively connected in series with the plurality of toggle switches one by one and then connected in parallel.

[0008] Further, the test device includes a cabinet body, the cabinet body is provided with a test chamber, the test chamber is provided with an openable first chamber door, and a test tooling is arranged in the test chamber. The test tooling is used to fix the NTC product to be tested so that the NTC product to be tested is connected to the test circuit.

[0009] Furthermore, the test tooling is provided with a fixing structure, and the fixing structure includes a wiring terminal. The wiring terminal is used to lock the pins of the NTC product to be tested on the test tooling so that the NTC product to be tested is connected to the test circuit.

[0010] Further, the test circuit further includes a capacitor and a discharge resistor. The capacitor and the load resistor are connected in parallel, and the discharge resistor is connected in parallel with the capacitor. The cabinet body is further provided with a first electrical chamber, and the first electrical chamber is provided with an openable second chamber door. The capacitor and the discharge resistor are detachably arranged in the first electrical chamber.

[0011] Furthermore, a first mounting bracket is arranged in the first electrical chamber, and the discharge resistor is detachably fixed on the first mounting bracket and connected to the test circuit. The detachable fixed connection method can be threaded connection, snap connection, etc.

[0012] Further, a second mounting bracket is arranged in the first electrical chamber, and the second mounting bracket is provided with a slot. The capacitor is detachably inserted into the slot and connected to the test circuit.

[0013] Further, a second electrical chamber is further arranged in the cabinet body, and the second electrical chamber is provided with a main control circuit for controlling the on / off of the test circuit.

[0014] Furthermore, the cabinet body is further provided with a door opening detection mechanism for detecting the opening and closing state of the first chamber door and transmitting it to the main control circuit for controlling the on / off of the test circuit.

[0015] Further, the number of the power supplies is two, and the output voltages of the two power supplies are different.

[0016] Advantageous technical effects of the present invention:

[0017] The present invention can realize the durability test of NTC products. By toggling the switch, the size of the load resistor can be adjusted conveniently, quickly, with high adjustment accuracy and high safety, and the whole system structure is compact and simple. Description of the Drawings

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0019] Figure 1 Structural diagram of a specific embodiment of the present invention;

[0020] Figure 2 Structural diagram of the resistance box of a specific embodiment of the present invention;

[0021] Figure 3 Structural diagram of the test equipment of a specific embodiment of the present invention;

[0022] Figure 4 Open state diagram of the test equipment of a specific embodiment of the present invention;

[0023] Figure 5 Structural diagram of the test tooling of a specific embodiment of the present invention;

[0024] Figure 6 Fixed structural diagram of the capacitor of a specific embodiment of the present invention;

[0025] Figure 7 Fixed structural diagram of the discharge resistor of a specific embodiment of the present invention;

[0026] Figure 8 Circuit diagram of the test circuit of a specific embodiment of the present invention;

[0027] Figure 9 Circuit diagram of the load resistance unit of a specific embodiment of the present invention;

[0028] Figure 10 Structural diagram of another embodiment of the present invention. Detailed implementation manners

[0029] To further illustrate each embodiment, the present invention provides accompanying drawings. These accompanying drawings are a part of the disclosure of the present invention, which are mainly used to illustrate the embodiments and can be combined with the relevant descriptions in the specification to explain the operating principles of the embodiments. With reference to these contents, those of ordinary skill in the art should be able to understand other possible implementation manners and the advantages of the present invention. The components in the figures are not drawn to scale, and similar component symbols are usually used to represent similar components.

[0030] The present invention will be further described below in conjunction with the accompanying drawings and specific implementation manners.

[0031] As Figure 1-9As shown in the figure, a durability test system for an NTC product includes a power supply 1, a test device 2, and a resistance box 3. The power supply 1, the test device 2, and the resistance box 3 are electrically connected in sequence to form a test circuit. The test device 2 is used to install the NTC product 4 to be tested so that the NTC product 4 to be tested is connected to the test circuit. The resistance box 3 is provided with a load resistance unit for providing the load resistance Rload in the test circuit to simulate the impedance of the load. The resistance box is provided with a toggle switch 31 for adjusting the value of the load resistance unit. By operating the toggle switch 31, the size of the load resistance Rload can be adjusted conveniently, quickly, with high adjustment accuracy and high safety.

[0032] Specifically, the load resistance unit includes multiple sub-load resistors. The number of toggle switches 31 is the same as the number of sub-load resistors. The multiple sub-load resistors are respectively connected in series with the multiple toggle switches 31 one by one and then connected in parallel, but it is not limited to this. By toggling different toggle switches, different sub-load resistors are connected to the test circuit, thereby adjusting the resistance value of the load resistance Rload, and further adjusting the current size in the test circuit. The more the number of sub-load resistors and toggle switches 31, the more current levels can be adjusted in the test circuit, and the higher the accuracy can be achieved.

[0033] Figure 7 The circuit structure diagram shows that the number of sub-load resistors and toggle switches 31 is 8. The 8 sub-load resistors are respectively Rload1 - Rload8, and the 8 toggle switches 31 are respectively K1 - K8. The toggle switches K1 - K8 can be used alone to form 8 levels of current adjustment, or can be used in combination to form more current level adjustments. Of course, in some embodiments, the number of sub-load resistors and toggle switches 31 can also be less than 8 or more than 8, which is specifically set according to actual needs.

[0034] The resistance values of the multiple sub-load resistors can be the same or different, and the specific resistance values can be selected according to the actual situation.

[0035] In this specific embodiment, the resistance box 3 is of a cuboid structure, and the toggle switch 31 is arranged on the front side panel of the resistance box 3, with a compact structure and convenient operation, but it is not limited to this.

[0036] In this specific embodiment, the test device 2 includes a cabinet 21. The cabinet 21 is provided with a test chamber 22. The test chamber 22 is provided with an openable first chamber door 221. The test chamber 22 is provided with a test fixture 25 for fixing the NTC product 4 to be tested so that the NTC product 4 to be tested is connected to the test circuit.

[0037] By providing a test chamber 22 with an openable first chamber door 221, it is convenient to disassemble and assemble the NTC product 4 to be tested, and the NTC product 4 to be tested can be placed in a closed space, making it less susceptible to external environmental interference and resulting in good test results.

[0038] In this specific embodiment, the cabinet 21 has a cuboid structure, making the structure reasonable and compact. However, this is not limiting, and in some embodiments, the structure of the cabinet 21 can be set according to actual situations.

[0039] In this specific embodiment, the test chamber 22 is provided in the upper right part of the cabinet 21, with a more reasonable structure and more convenient use. However, this is not limiting, and in some embodiments, the test chamber 22 can also be provided in other positions of the cabinet 21.

[0040] In this specific embodiment, the test fixture 25 is provided with a fixing structure, which includes a lockable terminal 251. The terminal 251 is used to lock the pins of the NTC product 4 to be tested onto the test fixture 25, thereby electrically connecting the NTC product 4 to be tested into the test circuit. With this fixing structure, the structure is simple, the disassembly and assembly are convenient, and the fixing effect is good. However, this is not the only limit, and in some embodiments, other existing fixing structures can also be used to implement the fixing structure. Preferably, the terminal is made of ceramic material.

[0041] Preferably, in this embodiment, the number of fixing structures is multiple, which are used to fix multiple NTC products 4 to be tested onto the test fixture 25, so that multiple NTC products 4 to be tested are connected in series and incorporated into the test circuit, as Figure 5 shows the series fixing of 3 NTC products 4 to be tested. By providing multiple fixing structures, multiple NTC products can be tested at one time, improving the test efficiency.

[0042] In this specific embodiment, the first chamber door 221 is provided with a transparent observation window 222, which is convenient for observing the situation inside the test chamber 22 and makes the use more convenient.

[0043] Further, the test circuit further includes a capacitor C1 and a discharge resistor Rb. The capacitor C1 is used to simulate the capacitive reactance of the load. The capacitor C1 and the load resistor Rload are connected in parallel and then connected in series in the test circuit. The discharge resistor Rb is connected in parallel with the capacitor C1 and is used to discharge the charge of the capacitor C1. The more specific circuit is as Figure 8 shown, where SW1 is a switch, B1 is a rectifier bridge, and D1 is a diode. This is already a relatively conventional test circuit and will not be elaborated further. However, this is not the only limit.

[0044] The cabinet body 21 is also provided with a first electrical chamber 23. The first electrical chamber 23 is provided with an openable second chamber door 231. The capacitor C1 and the discharge resistor Rb are detachably arranged in the first electrical chamber 23. With this structure, it is not only convenient to replace the capacitor C1 and / or the discharge resistor Rb, so that it can be applicable to the tests of NTC products of different specifications, with wide applicability, but also the capacitor C1 and the discharge resistor Rb are separated from the NTC product 4 to be tested, which will not affect the NTC product 4 to be tested, and the test effect is better.

[0045] In this specific embodiment, the first electrical chamber 23 is arranged at the lower part of the cabinet body 21, and the structure is more reasonable and compact, but it is not limited to this. In some embodiments, the first electrical chamber 23 can also be arranged at other positions of the cabinet body 21.

[0046] In this specific embodiment, a first mounting bracket 26 is arranged in the first electrical chamber 23. The discharge resistor Rb is electrically connected by being locked to the first mounting bracket 26 with screws (not shown in the figure) and is connected in series in the test circuit. With this fixing structure, not only the disassembly and assembly are simple, but also the fixing effect is good, improving the electrical contact performance. However, it is not limited to this. In some embodiments, the discharge resistor Rb can also be fixedly installed by using other existing detachable fixing methods, such as snap connection, etc.

[0047] In this specific embodiment, a second mounting bracket 27 is arranged in the first electrical chamber 23. The second mounting bracket 27 is provided with a slot 271. The capacitor C1 is detachably inserted into the slot 271 for electrical connection and is connected in series in the test circuit, which is easy to implement and the disassembly and assembly are convenient. However, it is not limited to this. In some embodiments, the capacitor C1 can also be fixedly installed by using other existing detachable fixing methods.

[0048] In this specific embodiment, a second electrical chamber 24 is further arranged in the cabinet body 21. The second electrical chamber 24 is provided with a main control circuit, and the main control circuit is used to control the on-off of the test circuit to perform the durability test. The main control circuit can be implemented by using a PLC controller or the like.

[0049] The second electrical chamber 24 is provided with an openable third chamber door 241, which is convenient for the installation and maintenance of the main control circuit. The second electrical chamber 24 is arranged on the left side of the test chamber 22 (i.e., the upper left part of the cabinet body 21), and the overall structure is more compact and reasonable, but it is not limited to this.

[0050] Furthermore, in this specific embodiment, the cabinet body 21 is also provided with a door opening detection mechanism 28. The door opening detection mechanism 28 is used to detect the opening and closing state of the first chamber door 221 and transmit it to the main control circuit for controlling the on-off of the test circuit, so that when the first chamber door 221 is opened, the test circuit is powered off, further improving the safety.

[0051] In this specific embodiment, the door opening detection mechanism 28 is arranged inside the first chamber door 221, and can be implemented by a microswitch, a proximity sensor, etc.

[0052] Furthermore, in this specific embodiment, a touch screen 29 is also provided. The touch screen 29 is connected to the main control circuit and is used to display relevant information and set test parameters (such as power-on time, number of power-on times, etc.).

[0053] In this specific embodiment, the touch screen 29 is arranged on the front side of the cabinet body 21 and corresponds to the second electrical chamber 24, with a compact and reasonable structure, but it is not limited thereto.

[0054] Furthermore, in this specific embodiment, an ammeter 200 is also arranged on the front side of the cabinet body 21. The ammeter 200 is used to display the current value flowing through the test circuit, facilitating an intuitive understanding of the current magnitude of the test circuit.

[0055] In this specific embodiment, the ammeter 200 is arranged above the touch screen 9, making the overall structure compact and reasonable, but it is not limited to this.

[0056] In this specific embodiment, the power supply 1 is an AC power supply, but it is not limited thereto. Preferably, the number of power supplies 1 is two, and the output voltages of the two power supplies 1 are different, being 120V and 240V respectively, but it is not limited to this. This enables the working voltage to be selectable, improving applicability, and the two power supplies 1 can also supply power together, reducing the load of the power supply 1 and enhancing safety and reliability. Of course, the working frequencies of the two power supplies 1 can also be different, such as 50Hz and 60Hz respectively.

[0057] In some embodiments, the number of power supplies 1 can be 1 or more than 2.

[0058] Furthermore, the number of test fixtures 25, load resistance units, capacitor C1, and discharge resistors Rb are all multiple. In this specific embodiment, the number of test fixtures 25, load resistance units, capacitor C1, and discharge resistors Rb are all 9. The 9 test fixtures 25, load resistance units, capacitor C1, and discharge resistors Rb are respectively connected one-to-one to form 9 independent test circuits, all of which are powered by the power supply 1, and 9 groups of NTC product tests can be carried out simultaneously, improving the test efficiency. Of course, in some embodiments, the number of test fixtures 25, load resistance units, capacitor C1, and discharge resistors Rb can be set according to actual needs.

[0059] The gears of multiple load resistance units can be the same or different to meet more different test requirements.

[0060] Preferably, in this specific embodiment, the resistance box 3 is separately arranged from the test device 2. Since the resistance box 3 generates a large amount of heat, separating it from the test device 2 will not affect the ambient temperature of the test chamber 22, and the test effect is better.

[0061] During the test, open the first chamber door 221, fix the NTC product 4 to be tested on the test fixture 25 to enter the test circuit, close the first chamber door 221, set the test parameters through the touch screen 29, and then start the test. The main control circuit controls the on-off of the test circuit according to the set test parameters to perform a durability test on the NTC product 4 to be tested. The test principle is already a very mature prior art and will not be elaborated here.

[0062] Of course, in some embodiments, the durability test system for the NTC product may further include an auxiliary test device 5, such as Figure 10 shown (the auxiliary test device 5 in the figure is only a simple illustration). The structure of the auxiliary test device 5 is roughly the same as that of the test device, except that the environment of the test chamber of the auxiliary test device 5 is different from that of the test chamber 22 of the test device 2. For example, the environment of the test chamber of the auxiliary test device 5 is a high and low temperature environment, and the environment of the test chamber 22 of the test device 2 is a normal temperature environment, etc. The auxiliary test device 5 and the test device 2 are electrically connected to the power supply 1 and the resistance box 3 through a changeover switch, so as to realize a test circuit under different test conditions.

[0063] The present invention can realize the durability test of the NTC product. By toggling the switch, the size of the load resistance can be adjusted conveniently, with high adjustment accuracy and high safety, and the entire system structure is compact and simple.

[0064] Although the present invention has been specifically shown and described in conjunction with the preferred embodiments, those skilled in the art should understand that various changes can be made to the present invention in terms of form and details without departing from the spirit and scope of the present invention defined by the appended claims, and all of them fall within the protection scope of the present invention.

Claims

1. A durability test system for NTC products, characterized in that: It includes a power supply, a test device and a resistance box. The power supply, the test device and the resistance box are electrically connected in sequence to form a test circuit. The test device is used to install the NTC product to be tested so that the NTC product to be tested is connected into the test circuit. The resistance box is provided with a load resistance unit for providing the load resistance in the test circuit. The resistance box is provided with a toggle switch for adjusting the value of the load resistance unit; The test device includes a cabinet body. The cabinet body is provided with a test chamber. The test chamber is provided with an openable first chamber door. The test chamber is provided with a test tooling for fixing the NTC product to be tested so that the NTC product to be tested is connected into the test circuit; The test circuit further includes a capacitor and a discharge resistor. The capacitor and the load resistor are connected in parallel. The discharge resistor is connected in parallel with the capacitor. The cabinet body is further provided with a first electrical chamber. The first electrical chamber is provided with an openable second chamber door. The capacitor and the discharge resistor are detachably arranged in the first electrical chamber.

2. The durability test system for NTC products according to claim 1, characterized in that: The load resistance unit includes a plurality of sub-load resistors. The number of toggle switches is the same as the number of sub-load resistors. The plurality of sub-load resistors are respectively connected in series with the plurality of toggle switches one by one and then connected in parallel.

3. The durability test system for NTC products according to claim 1, characterized in that: The test tooling is provided with a fixing structure. The fixing structure includes a wiring terminal for locking the pins of the NTC product to be tested on the test tooling so that the NTC product to be tested is connected into the test circuit.

4. The durability test system for NTC products according to claim 1, characterized in that: A first mounting bracket is provided in the first electrical chamber. The discharge resistor is detachably fixed on the first mounting bracket and connected in the test circuit.

5. The durability test system for NTC products according to claim 1, characterized in that: A second mounting bracket is provided in the first electrical chamber. The second mounting bracket is provided with a slot. The capacitor is detachably inserted into the slot and connected in the test circuit.

6. The durability test system for NTC products according to claim 1, characterized in that: A second electrical chamber is further provided in the cabinet body. The second electrical chamber is provided with a main control circuit for controlling the on-off of the test circuit.

7. The durability test system for NTC products according to claim 6, characterized in that: The cabinet body is further provided with a door opening detection mechanism for detecting the opening and closing state of the first chamber door and transmitting it to the main control circuit for controlling the on-off of the test circuit.

8. The durability test system for NTC products according to claim 1, characterized in that: The number of the power supplies is two, and the output voltages of the two power supplies are different.

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