CN108226729A - High-precision thin-film electro weak point test instrument - Google Patents

Abstract

A kind of high-precision thin-film electro weak point test instrument of the present invention including rack (1), by copper roller (2) of the copper roll shaft (3) in rack (1) and is arranged on the electrode assemblies being slidably electrically connected with copper roll shaft (3) of rack (1) side；The copper roll shaft (3) is rotatably connected by copper roller bearing (4), copper roller bearing insulating base (5) in insulation and copper roll bearing seat (6), and the copper roll bearing seat (6) is connected by copper roll bearing seat fixed screw (7) and rack (1)；The electrode assemblies include metab (8) and the electrode guide sleeve (9), compression spring bayonet lock (10) and the binding post (11) that are symmetrically installed on metab (8).Sampling resistor one end of the present invention is electrically connected with the binding post (11) of electrode assemblies, other end ground connection, and measuring accuracy is high.

Description

High-precision thin film electrical weakness tester

technical field

The invention relates to an electric weakness tester for testing the electrical properties of electrical plastic films, in particular to a high-precision film electric weakness tester.

Background technique

The existing electrical plastic film electric weakness tester generally includes a sample roller, a conductive rubber plate (connected to the high-voltage positive electrode), an electrode copper roller (the high-voltage negative electrode is also grounded), a winding roller, and at least one flattening roller is provided at the front end of the electrode roller. roller, at least one guide roller is arranged at the rear end of the electrode roller, and a control part is formed. Its working principle is that when the winding roller drives a film of a certain width on the sample roller to pass through the electrode roller, an equipotential conductive rubber plate of a certain width set on the upper end of the electrode roller is flexible and in horizontal line contact with the film, and the voltage is applied to the film. . Conductive rubber plate (high-voltage positive electrode), moving film, and electrode roller (high-voltage negative electrode is also grounded) constitute a high-voltage circuit. The leakage current of this high-voltage circuit changes with the moving film. When there is a weak point (defect) somewhere in the film , the leakage current of the high-voltage circuit will increase suddenly, and the leakage current of this sudden increase in the high-voltage circuit is collected, that is, the electrical weakness of the film is tested. CN201017020Y discloses such a thin-film electrical weakness tester. Its electrode copper roller is directly grounded (high-voltage negative pole) through the shaft and bearing and the frame. The method of collecting leakage current is to connect a current sensor to the high-voltage output circuit, and the weak voltage signal induced by the current sensor is input to a processor such as a single-chip microcomputer or PLC. For judging whether there is an electrical weakness in the film, the accuracy and sensitivity of the current sensor are low, which directly affects the test accuracy of the instrument.

Contents of the invention

The purpose of the present invention is to provide a high-precision thin film electric weakness tester for the deficiencies of the prior art. The electrode copper roller is isolated from the frame through the bearing insulating seat, the electrode copper roller is not directly grounded, and the electrode roller is grounded through the sampling resistor ( High-voltage negative pole), the leakage current generated by the high-voltage circuit during the test generates a voltage signal that meets the accuracy requirements on the sampling resistor, and inputs the voltage signal that meets the accuracy requirements to a processor such as a single-chip microcomputer or PLC to determine whether the film has an electrical weakness. , the test accuracy is improved.

Technical solutions:

In order to achieve the above object, the present invention adopts the following technical solutions: including a frame, a copper roller mounted on the frame through a copper roller shaft, and an electrode assembly arranged on one side of the frame and electrically connected to the copper roller shaft in a sliding manner; The copper roller shaft is rotatably connected to the copper roller bearing seat insulated by the copper roller bearing and the copper roller bearing insulating seat, and the copper roller bearing seat is fixedly connected to the frame by the copper roller bearing seat fixing screw.

Further, the electrode assembly includes a metal base, and an electrode guide sleeve symmetrically fixed on the metal base, a compression spring pin and a terminal; the electrode guide sleeve is provided with an electrode fixedly connected to the electrode wire. The electrode and the electrode guide sleeve are in clearance fit; the compression spring bayonet is provided with an electrode compression spring that presses the electrode so that it is in close contact with the copper roller shaft, and the electrode wire is fixedly connected to the terminal.

Further, the metal base is in the shape of a ring, and is fixedly connected to the insulating base by fixing screws of the metal base.

Further, the insulating base is in the shape of a ring, and is fixedly connected to the copper roller bearing seat through fixing screws of the insulating base.

Further, the metal base is symmetrically provided with U-shaped grooves for the fixing screws of the insulating base to pass through.

Further, the fixing screws of the metal base and the fixing screws of the insulating base are set at a certain angle.

Preferably, the contact surface between the electrode and the copper roller shaft is arranged as an arc-shaped surface consistent with the radial direction of the copper roller shaft.

Preferably, the electrode material is graphite.

Preferably, the electrode compression spring is a planar scroll spring.

Compared with prior art, the beneficial effect of the present invention:

In the present invention, 1. the copper roller shaft is insulated from the frame (frame grounding) through the bearing insulating seat, and 2. the electrode assembly is also insulated from the frame (frame grounding) through the insulating base; the copper roller shaft and the electrode assembly are in a tight Slidable electrical contacts. One end of the sampling resistor is electrically connected to the terminal of the electrode assembly, and the other end is grounded. During the test, the leakage current generated by the high-voltage circuit generates a voltage signal in the sampling resistor. According to the formula: U (voltage) = R (resistance) * I (current), selecting a sampling resistor with an appropriate resistance value can generate a voltage signal that meets the accuracy requirements. The voltage signal that meets the accuracy requirements is input to a processor such as a single-chip microcomputer or PLC to judge whether there is an electrical weakness in the film. This leakage current sampling method greatly improves the test accuracy.

Description of drawings:

Fig. 1 is a structural representation of the present invention;

Fig. 2 is the right view of the present invention;

Fig. 3 is a top view of the present invention;

Fig. 4 is a schematic diagram of the leakage current sampling circuit in the present invention

Among them, 1 frame, 2 copper rollers, 3 copper roller shafts, 4 copper roller bearings, 5 copper roller bearing insulation seats, 6 copper roller bearing seats, 7 copper roller bearing seat fixing screws, 8 metal bases, 9 electrode guide sleeves, 10 clip pins, 11 binding posts, 12 insulating bases, 81 metal base fixing screws, 90 electrodes, 91 electrode wires, 101 electrode compression springs, 121 insulating base fixing screws, and 200 is the device of the present invention.

Detailed ways:

As shown in Figure 1-3, a kind of high-precision film electric weakness tester of the present invention comprises frame (1), is installed on the copper roller (2) on the frame (1) by copper roller shaft (3), And the electrode assembly that is arranged on one side of the frame (1) and is slidably electrically connected to the copper roller shaft (3); the copper roller shaft (3) passes through the copper roller bearing (4), the copper roller bearing insulating seat (5 ) is insulated and rotatably connected with the copper roller bearing seat (6), and the copper roller bearing seat (6) is fixedly connected with the frame (1) through the copper roller bearing seat fixing screw (7); the electrode assembly includes The metal base (8), and the electrode guide sleeve (9), compression spring bayonet (10) and terminal post (11) symmetrically fixed on the metal base (8), the electrode guide sleeve (9) is provided with The electrode (90) of the electrode wire (91) is fixedly connected, and the electrode (90) is in clearance fit with the electrode guide sleeve (9), and the pressing spring pin (10) is provided with a pressing electrode (90) It is an electrode compression spring (101) in close contact with the copper roller shaft (3), and the electrode lead wire (91) is fixedly connected to the terminal post (11).

The metal base (8) is ring-shaped, and is fixedly connected to the insulating base (12) by metal base fixing screws (81); the insulating base (12) is ring-shaped, and is fixed by the insulating base fixing screws (121) Be fixed on the copper roller bearing seat (6).

The metal base (8) is symmetrically provided with U-shaped grooves for the passage of the fixing screws (121) of the insulating base.

The fixing screw (81) of the metal base and the fixing screw (121) of the insulating base are set at a certain angle.

In order to increase the contact surface between the electrode (90) and the copper roller shaft (3), the contact surface between the electrode (90) and the copper roller shaft (3) is arranged as an arc-shaped surface radially consistent with the copper roller shaft (3).

In order to reduce the wear of the copper roller shaft (3), the electrode (90) is made of graphite.

The electrode compression spring (101) is a planar scroll spring.

The above-mentioned high-precision thin film electric weakness tester works like this:

The voltage generated by the high-voltage generator is output to the conductive rubber plate by the internal current-limiting resistor. The electric rubber plate is in flexible contact with the film, and the voltage is applied to one side of the film, and the other side of the film is in contact with the electrode copper roller (2). The roller (2) is in close contact with the electrode through the copper roller shaft (3). One end of the sampling resistor is electrically connected to the terminal (11) of the electrode assembly, and the other end is grounded (high voltage negative pole). In this way, the high-voltage negative and positive electrodes pass through the current-limiting resistor, film equivalent resistance, and sampling resistor to the high-voltage negative electrode to form a voltage loop. The film to be tested is between the upper electrode (conductive rubber plate) and the lower electrode (electrode copper roller) that is applied with voltage. Moving, the normal film (that is, when there is no electrical weakness) has a large insulation resistance (10 ³ MΩ level), the leakage current in the voltage loop is at the microampere level, and the voltage generated on the sampling resistor can reach the millivolt level. When there is a weak point (flaw) somewhere in the film, the leakage current of this high-voltage circuit will suddenly change to milliamp level, and the voltage generated on the sampling resistor can reach volt level. Such sampling voltage is enough to meet the needs of processors such as microcontrollers or PLC Accuracy requirements, so the detection accuracy of electrical weakness is greatly improved.

Claims (9)

1. a kind of high-precision thin-film electro weak point test instrument, including rack (1), by copper roll shaft (3) in rack (1) Copper roller (2) and the electrode assemblies being slidably electrically connected with copper roll shaft (3) for being arranged on rack (1) side；The copper roll shaft (3) it is rotatably connected by copper roller bearing (4), copper roller bearing insulating base (5) in insulation and copper roll bearing seat (6), the copper Roll bearing seat (6) is connected by copper roll bearing seat fixed screw (7) and rack (1).

2. a kind of high-precision thin-film electro weak point test instrument according to claim 1, it is characterized in that：The electrode assemblies packet Electrode guide sleeve (9), compression spring bayonet lock (10) and the binding post for including metab (8) and being symmetrically installed on metab (8) (11)；The electrode (90) of connected electrode cable (91) is provided in the electrode guide sleeve (9), the electrode (90) is led with electrode (9) are covered in clearance fit；Top pressure electrode (90) is provided on the compression spring bayonet lock (10) makes what it was in close contact with copper roll shaft (3) Electrode compression spring (101), the electrode cable (91) are affixed to binding post (11).

3. high-precision thin-film electro weak point test instrument according to claim 1, it is characterized in that：The metab (8) is in Annular shape is connected in by metab fixed screw (81) on insulator foot (12).

4. a kind of high-precision thin-film electro weak point test instrument according to claim 1, it is characterized in that：The insulator foot (12) it in annular shape, is connected in copper roll bearing seat (6) by insulator foot fixed screw (121).

5. a kind of high-precision thin-film electro weak point test instrument according to claim 1, it is characterized in that：The metab (8) it is symmetrical offer for insulator foot fixed screw (121) by U-type groove.

6. a kind of high-precision thin-film electro weak point test instrument according to claim 1, it is characterized in that：The metab is consolidated Determine screw (81) and insulator foot fixed screw (121) setting in a certain angle.

7. a kind of high-precision thin-film electro weak point test instrument according to claim 1, it is characterized in that：The electrode (90) with Copper roll shaft (3) contact surface is arranged to the arc shaped surface radially consistent with copper roll shaft (3).

8. a kind of high-precision thin-film electro weak point test instrument according to claim 1, it is characterized in that：The electrode (90) material selection graphite.

9. a kind of high-precision thin-film electro weak point test instrument according to claim 1, it is characterized in that：The electrode compression spring (101) it is plane scroll spring.