Capacitor detection device

Abstract

The utility model provides a capacitor detection device, which is used for detecting a capacitor and comprises a half-wave rectification circuit, a test clamp which is electrically connected to a direct current output loop of the half-wave rectification circuit and is used for electrically contacting the positive electrode and the negative electrode of the tested capacitor, and a boost monitoring instrument which is connected in parallel with the test clamp. The half-wave rectification circuit outputs a pulsating direct current signal with only a positive half cycle to intermittently charge the tested capacitor, and the boost monitoring instrument detects the voltage change in the test process of the capacitor in real time. Because the pulsating direct-current electric signal is intermittently charged, in the interval time period of two times of charging, if the capacitor to be detected is short-circuited, the capacitor to be detected can be quickly discharged, so that the voltage is obviously reduced, and a bad capacitor can be accurately identified according to the voltage change amplitude and then is removed at a subsequent station; and the screening rate of capacitor short-circuit defective products is improved to 100%.

Description

Technical Field

[0001] The utility model relates to the technical field of capacitor production detection, in particular to a detection device capable of quickly screening short-circuit defective capacitors. Background Art

[0002] After the electrolytic capacitor is produced, it needs to undergo parameter detection and aging test before it can be packaged and shipped. However, even after strict parameter detection and aging test, some defective products will still be missed, such as unstable capacity. The reason for unstable capacity is that the capacitor has short circuit, false short circuit and other phenomena. Some short circuits are caused by internal impurities. During the test process, the short circuit discharge will cause the local electrolyte to dry up. After the electrolyte is dried up, the short circuit area is not conductive, so the capacitor will return to normal in a short time, but when the electrolyte re-immerses in the area, a short circuit will occur again. This situation is very difficult to detect, which brings great hidden dangers to subsequent use.

[0003] The authorization announcement number CN212749068U discloses a capacitor detection circuit device, the principle of which is to use a large current pulse signal to perform an impact test on the capacitor under extreme conditions, thereby detonating the capacitor with a short circuit. However, due to the different short circuit conditions of capacitors, the situation is relatively complicated, such as the short circuit phenomenon mentioned above, this impact detonation method cannot completely screen out bad capacitors, and the defective product screening rate is only 50%-60%. Therefore, the market needs a test device with a higher short circuit defective product screening rate. Utility Model Content

[0004] The utility model provides a capacitor detection device, which can greatly improve the screening rate of capacitor short-circuit defective products.

[0005] In order to achieve the above purpose, the technical solution adopted by the utility model is:

[0006] A capacitor detection device is used to detect capacitors, comprising a half-wave rectifier circuit, a test clip electrically connected to a DC output loop of the half-wave rectifier circuit and used to electrically contact the positive and negative electrodes of the tested capacitor, and a boost monitoring instrument connected in parallel with the test clip.

[0007] A preferred embodiment, the detection device includes multiple groups arranged in parallel.

[0008] In a preferred embodiment, the AC input end of the half-wave rectifier circuit of each group of the detection devices is electrically connected to an isolation transformer.

[0009] In a preferred embodiment, the input-output voltage ratio of the isolation transformer is 1:1.

[0010] In a preferred solution, the input ends of the isolation transformers of the detection devices are commonly connected to an adjustable transformer.

[0011] In a preferred embodiment, the adjusting handle of the adjustable transformer is controlled to rotate by a stepping motor.

[0012] In a preferred solution, a first resistor for protection is further connected in series between the input terminal of the boost monitoring instrument and the positive terminal of the test clip.

[0013] In a preferred solution, a second resistor for current limiting is further arranged in series on the return line of the DC output loop of the half-wave rectifier circuit.

[0014] The beneficial effects of the utility model are as follows: during the test, the positive and negative electrodes of the capacitor are connected by contacting the two poles of the test clip, and then a pulsating DC signal with only a positive half cycle is output through a half-wave rectifier circuit to intermittently charge the tested capacitor, and a voltage change during the capacitor test is detected in real time by a boost monitoring instrument; since the pulsating DC signal is intermittently charged, in the interval between two charges, if the tested capacitor has a short circuit, it will discharge quickly, resulting in a significant drop in voltage, and defective capacitors can be accurately identified based on the voltage change amplitude, and then they can be removed at subsequent workstations. By testing capacitors with the detection device of this scheme, the screening rate of defective capacitors with short circuits can be increased to 100%, which completely solves the problem of difficulty in detecting defective products with slight short circuits in the capacitor production industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The utility model is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0016] Figure 1 It is the principle diagram of the detection device in the embodiment;

[0017] Figure 2 is a circuit diagram of the detection device in the embodiment. DETAILED DESCRIPTION

[0018] The utility model is further described below in conjunction with the accompanying drawings:

[0019] refer to Figure 1 and Figure 2 A capacitor detection device is used to detect a capacitor, comprising a half-wave rectifier circuit 1, a test clip 2 electrically connected to a DC output circuit of the half-wave rectifier circuit 1 and used for electrically contacting the positive and negative electrodes of the capacitor to be tested, and a boost monitoring meter 3 connected in parallel with the test clip 2.

[0020] During the test, the positive and negative poles of the capacitor are connected by contacting the two poles of the test clip 2, and then the half-wave rectifier circuit 1 outputs a pulsating DC signal with only the positive half cycle to intermittently charge the tested capacitor, and the boost monitoring instrument 3 detects the voltage change during the capacitor test in real time; since the pulsating DC signal is intermittently charged, in the interval between two charges, if the tested capacitor has a short circuit, it will discharge quickly, resulting in a significant drop in voltage, and the defective capacitor can be accurately identified based on the voltage change amplitude, and then it can be removed at the subsequent workstation. By testing the capacitor with the detection device of this scheme, the screening rate of defective capacitor short-circuit products can be increased to 100%, which completely solves the problem of difficulty in detecting defective products with slight short circuits in the capacitor production industry.

[0021] In a preferred embodiment, the detection device in this embodiment includes multiple groups arranged in parallel. By setting multiple groups of detection devices in parallel, multiple rounds of continuous testing can be performed on the continuously driven capacitors, thereby ensuring that no defective capacitors are missed and truly achieving a 100% detection rate of short-circuit defective products.

[0022] In a preferred embodiment, the AC input end of the half-wave rectifier circuit 1 of each group of the detection devices in this embodiment is electrically connected to an isolation transformer 4. The isolation transformer 4 not only improves the safety of the detection device, but also prevents each group of detection devices from interfering with each other, making the test more accurate.

[0023] In a preferred embodiment, the input-output voltage ratio of the isolation transformer 4 of this embodiment is 1:1. The 1:1 isolation transformer 4 keeps the DC voltage of the input detection device at a high voltage, so that the capacitor voltage change monitored by the boost monitoring instrument 3 is more obvious, thereby more accurately screening out short-circuit defective products.

[0024] In a preferred embodiment, the input end of the isolation transformer 4 of each detection device of this embodiment is commonly connected to an adjustable transformer 5. Further, the adjustment handle of the adjustable transformer 5 is controlled to rotate by a stepper motor. The adjustable transformer 5 can adaptively select the required test voltage according to the rule of the tested capacitance, and is controlled by a stepper motor, so that the test is more intelligent and avoids errors in adjustment.

[0025] In a preferred solution, in this embodiment, a first resistor for protection is also connected in series between the input end of the boost monitoring instrument 3 and the positive end of the test clip 2. The first resistor can prevent the boost monitoring instrument 3 from being damaged.

[0026] In a preferred embodiment, a second resistor for current limiting is also connected in series on the return line of the DC output loop of the half-wave rectifier circuit 1 in this embodiment. The second resistor plays a role in current limiting and protecting the detection device.

[0027] The above description does not limit the technical scope of the present invention. Any modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A capacitor detection device, used for detecting a capacitor, characterized in that: The invention comprises a half-wave rectifier circuit, a test clip electrically connected to the DC output loop of the half-wave rectifier circuit and used for electrically contacting the positive and negative electrodes of the tested capacitor, and a boost monitoring instrument connected in parallel with the test clip.

2. A capacitor detection device according to claim 1, characterized in that: The detection device comprises a plurality of groups arranged in parallel.

3. A capacitor detection device according to claim 2, characterized in that: The AC input end of the half-wave rectifier circuit of each group of the detection devices is electrically connected to an isolation transformer.

4. A capacitor detection device according to claim 3, characterized in that: The input-to-output voltage ratio of the isolation transformer is 1:

1.

5. A capacitor detection device according to claim 3, characterized in that: The input ends of the isolation transformers of the detection devices are commonly connected to an adjustable transformer.

6. A capacitor detection device according to claim 5, characterized in that: The adjusting handle of the adjustable transformer is controlled to rotate by a stepping motor.

7. A capacitor detection device according to claim 1, characterized in that: A first resistor for protection is also connected in series between the input end of the boost monitoring instrument and the positive terminal of the test clip.

8. A capacitor detection device according to claim 7, characterized in that: A second resistor for current limiting is also arranged in series on the return line of the DC output loop of the half-wave rectifier circuit.

Images