CN214150962U - Circuit breaker anti-tripping test device - Google Patents

Abstract

The utility model discloses a circuit breaker anti-bounce test device relates to electric power system test tool field. The traditional circuit breaker anti-tripping test needs two testers to respectively carry out one test wire, two testers are matched, and the method of directly using the test wire short circuit easily causes the risks of test failure due to unreliable contact in the short circuit and direct current grounding caused by the test wire touching a screen cabinet. The utility model discloses an experimental clamp and controlling means, experimental clamp is including pressing from both sides the foot, supporting spring, pressure shell fragment and experimental contact pin, controlling means includes the device casing, dial the shelves cap, remove the contact, combined floodgate contact and separating brake contact, experimental contact pin is equipped with the metal brush, it is equipped with 4 contact pins to remove the contact, through removing the test position that the contact mobile location arrived the difference, make the different contact pins and combined floodgate contact and the separating brake contact of removing the contact carry out the contact and switch on and break off, carry out different jump-proof tests, reducible experimental number, promote experimental security.

Description

Circuit breaker anti-tripping test device

Technical Field

The utility model relates to an electric power system test tool field especially relates to a circuit breaker anti-bounce test device.

Background

Anti-bounce is a short for preventing "breaker bounce". The circuit breaker jumping means that the switching-on output end always has switching-on voltage due to the reasons of adhesion of a switching-on or remote-connection joint of a switching-on loop and the like. At the moment, if a permanent fault occurs in primary equipment, the breaker is tripped by the action of the protection device, the breaker is switched on again due to the adhesion of a switching-on contact, the breaker is tripped by the protection device again due to the permanent fault, and the phenomenon is called 'breaker tripping'. Once the circuit breaker jumps, the circuit breaker can be damaged, the circuit breaker can explode seriously, or the power failure range of an accident is enlarged. The circuit breaker trip prevention function is essential in the operation circuit. Therefore, the anti-tripping test of the circuit breaker is a very important test item in the debugging process. The circuit breaker anti-tripping test can be divided into a closed position anti-tripping test and an open position anti-tripping test, the closed position anti-tripping test refers to the anti-tripping test performed when the circuit breaker is in a closed position, the traditional test method adopts two test wires, two testers respectively carry one test wire, one test wire is used for short-circuiting the positive end of a control loop and a terminal of a closing loop, the other test wire is used for short-circuiting the positive end of the control loop and the terminal of an opening loop, at the moment, if the switch cannot be closed after being opened, the circuit breaker anti-tripping function is correct, and otherwise, the circuit breaker anti-tripping function is incorrect. The traditional test method for preventing tripping at an open position adopts two test wires, two testers respectively hold one test wire, one test wire is used for short-circuiting the positive end of the control loop and the terminal of the opening loop, the other test wire is used for short-circuiting the positive end of the control loop and the terminal of the closing loop, at the moment, if a switch cannot be closed again after being closed and opened instantly, the tripping prevention function of the circuit breaker is correct, and otherwise, the tripping prevention function is incorrect.

Because the traditional test method needs two persons to cooperate, the waste of human resources is caused, and the method of directly using the test wire for short circuit easily causes the test failure due to unreliable contact during short circuit and the risk of direct current grounding caused by the test wire touching the screen cabinet, and the safety is low.

SUMMERY OF THE UTILITY MODEL

The utility model discloses the technical problem that solve and the technical task that provides are perfect and improve prior art scheme, provide a circuit breaker and prevent jumping test device to promote experimental security and reduce experimental operation number and aim at. Therefore, the utility model adopts the following technical scheme.

A breaker anti-tripping test device comprises a test clamp and a control device, wherein the test clamp is connected to a terminal row in a clamping manner, the control device is used for controlling breaker anti-tripping test operation, the test clamp comprises a clamping assembly and a test contact pin connected to the clamping assembly, the control device comprises a device shell, a shifting cap, a movable contact piece, a closing contact piece and a separating contact piece, the movable contact piece, the closing contact piece and the separating contact piece are arranged in the device shell, 4 vertical contact pins are transversely arranged at the lower part of the movable contact piece and respectively comprise a first contact pin, a second contact pin, a third contact pin and a fourth contact pin from left to right, the closing contact piece and the separating contact piece are vertical elastic contact pieces fixed at the bottom in the device shell, the closing contact piece and the separating contact piece are connected and fixed at the lower part in the device shell and are positioned at the right side of the first contact pin of the closing contact piece, the separating contact piece is positioned at the left side of the fourth contact pin, the device comprises a device shell, a shifting cap, a movable contact piece, a positive electric interface, an opening interface and a closing interface, wherein the shifting cap is arranged on the top surface of the device shell and penetrates through the device shell downwards to be connected and fixed with the movable contact piece, the inner wall of one side of the device shell is provided with the positive electric interface, the opening interface and the closing interface, the movable contact piece is connected to the positive electric interface through a lead, the closing contact piece is correspondingly connected to the closing interface through a lead, the opening contact piece is correspondingly connected to the opening interface through a lead, the positive electric interface, the opening interface and the closing interface are respectively connected with 1 test clip through insulated leads, and a combined part of the shifting cap and the movable contact piece can move transversely and be positioned at different positions so as to enable different contact pins of the movable contact piece to be in contact with and disconnected with the closing contact piece and the opening contact piece.

When the device uses, at first will dial the shelves cap and arrange the vacancy in, clip the separating brake terminal respectively with the clamping components of 3 experimental clamps, closing terminal, the terminal row that the positive electricity terminal corresponds, with the reliable metal screw in the contact terminal of experimental contact pin, then make the mobile contact piece remove through removing the shelves cap, through moving the mobile contact piece shift position to different experimental positions, make the different contact pin of mobile contact piece and closing contact piece and separating brake contact piece carry out the contact and switch on and break off, carry out different jump-proof tests, the device overall structure is simple, and is small, light in weight, and easy operation is convenient, compare in traditional 2 people operation tests, only need 1 individual just can realize the jump-proof test, the unreliable problem of contact can not appear, the security of test has been promoted and the experimental number of operation people is reduced.

As a preferable technical means: the clamping assembly comprises 2 clamping feet, the 2 clamping feet comprise clamping feet claws and clamping foot handles, clamping foot connecting parts are arranged between the clamping feet claws and the clamping foot handles, the 2 clamping feet are rotatably connected through the clamping foot connecting parts, supporting springs are connected between the 2 clamping foot handles, and the clamping feet claws are provided with claw hooks. Through the elasticity of supporting spring and the rotatable connection of clamping foot connecting portion, can make the clamping foot claw effectively press from both sides tight terminal row, the setting of claw hook can effectively prevent clamping foot claw from the slippage on the terminal row.

As a preferable technical means: the clamping foot claw is provided with a telescopic structure part. For the terminal strip with different widths, the telescopic structure parts of the clamping claws can effectively realize the clamping adaptation of the clamping claws to the terminal strip with different sizes and widths.

As a preferable technical means: the test contact pin is connected with one of the clamping foot handles through the pressure elastic sheet, and the test contact pin is rotatably connected with the pressure elastic sheet. The test contact pin and the telescopic structure of the pressure spring piece are matched with the clamping claw, so that the angle of the test contact pin can be adjusted, and the test contact pin can be accurately inserted into a screw hole of the terminal.

As a preferable technical means: the head of the lower end of the test pin is provided with a metal brush. The metal brush is inserted into the screw hole of the terminal and is contacted with the metal screw in the terminal, so that the contact is more reliable, and the conductive effect is better.

As a preferable technical means: the device shell top surface one side be equipped with transverse arrangement's experimental sign, experimental sign include neutral position, combined floodgate, close the position and prevent jumping, separating brake and separating and prevent jumping, the device shell in be equipped with the positioning groove who corresponds with each experimental sign position, the removal contact on be equipped with elastic positioning element, when removal contact lateral shifting, elastic positioning element can match the location with the positioning groove that each experimental sign corresponds. The position location when different test items are conveniently realized.

As a preferable technical means: when the shifting cap is arranged in the neutral test mark, the distance between the second contact pin and the closing contact piece is 1 unit, the distance between the third contact pin and the opening contact piece is 1 unit, the distance between the first contact pin and the closing contact piece is 2 units, and the distance between the fourth contact pin and the opening contact piece is 2 units. The accurate position distance setting of four contact pins and separating brake contact and combined floodgate contact, the accessible removes the contact and moves different positions, can effectively realize different contact pins and combined floodgate contact and separating of separating brake contact, effectively realizes various anti-bouncing tests.

As a preferable technical means: the device shell is internally provided with a guide rail groove used for moving the contact piece to move transversely, and the top of the device shell is provided with a transverse groove hole used for shifting the gear cap to move transversely. The transverse movement of the combined part of the gear shifting cap and the movable contact piece can be effectively realized.

As a preferable technical means: one side of the shifting cap facing the test mark is in an indication triangle shape. The test device has an indicating function, and is convenient for operators to judge the current test items.

As a preferable technical means: the switching-off interface adopts green marks on the outer surface side of the device shell, the switching-on interface adopts red marks on the outer surface side of the device shell, and the positive interface adopts black marks on the outer surface side of the device shell. The identification of different interfaces is conveniently realized, and the corresponding wiring of the insulated wire is convenient.

As a preferable technical means: the clamping pins and the pressure spring pieces are made of insulating plastics, the outer surface of the test contact pin is made of insulating materials, a lead connecting port is formed in the tail of the test contact pin, and the lead connecting port is connected with the metal brush through a metal piece; the device shell is made of insulating plastic. The safety of operation can be effectively improved.

Has the advantages that: the device overall structure is simple, and is small, light in weight, and easy operation is convenient, compares in traditional 2 people operation tests, only needs 1 individual just can realize preventing the jump test, can not appear contacting the insecure problem, has promoted experimental security and has reduced experimental operation number.

Drawings

Fig. 1 is a schematic view of the structure of the test clip of the present invention.

Fig. 2 is a schematic diagram of the internal structure of the control device of the present invention.

Fig. 3 is a schematic view of the connection structure of the pressure spring and the test pin of the present invention.

Fig. 4 is a schematic sectional structure view of the telescopic structure of the present invention.

Fig. 5 is a schematic top view of the control device of the present invention.

Fig. 6 is a schematic diagram of the movable contact piece of the present invention matching with the device housing.

Fig. 7 is a schematic view of the positioning of the elastic positioning element of the present invention.

Fig. 8 is a schematic diagram of the closing state of the control device of the present invention.

Fig. 9 is a schematic diagram of the closed position anti-bouncing state of the control device of the present invention.

Fig. 10 is a schematic diagram of the opening state of the control device of the present invention.

Fig. 11 is a schematic diagram of the position-separated anti-jumping state of the present invention.

In the figure: 1-clamping feet; 2-a support spring; 3-a pressure spring sheet; 4-test pin insertion; 5-metal brush; 6-device housing; 7-gear shifting cap; 8-moving contact piece; 9-a closing contact piece; 10-opening contact piece; 11-positive electrical interface; 12-a brake-separating interface; 13-a switching-on interface; 14-a resilient positioning element; 101-gripper jaw; 102-a pinch grip; 103-clamping foot connecting part; 104-a telescoping structure; 105-a claw hook; 601-positioning a groove; 602-guide rail groove; 701-indicating a triangular shape; 801-first contact pin; 802-second contact pin; 803-third contact pin; 804-fourth contact pin.

Detailed Description

The technical solution of the present invention will be further described in detail with reference to the accompanying drawings.

As shown in fig. 1 and 2, an anti-tripping test device for a circuit breaker comprises a test clip connected to a terminal row in a clamping manner and a control device for controlling the anti-tripping test operation of the circuit breaker, wherein the test clip comprises a clamping assembly and a test pin 4 connected to the clamping assembly, the control device comprises a device shell 6, a shifting cap 7, a movable contact 8, a closing contact 9 and an opening contact 10, the movable contact 8, the closing contact 9 and the opening contact 10 are arranged in the device shell 6, 4 vertical contacts are transversely arranged at the lower part of the movable contact 8, a first contact 801, a second contact 802, a third contact 803 and a fourth contact 804 are respectively arranged from left to right, the closing contact 9 and the opening contact 10 are vertical elastic contacts fixed at the bottom in the device shell 6, the closing contact 9 and the opening contact 10 are connected and fixed at the lower part in the device shell 6 and the right side of the first contact 801, the opening contact 10 is located on the left side of the fourth contact 804, the shifting cap 7 is arranged on the top surface of the device shell 6 and penetrates through the device shell downwards to be connected and fixed with the movable contact 8, a positive electric interface 11, an opening interface 12 and a closing interface 13 are arranged on the inner wall of one side of the device shell 6, the movable contact 8 is connected to the positive electric interface 11 through a lead, the closing contact 9 is correspondingly connected to the closing interface 13 through a lead, the opening contact 10 is correspondingly connected to the opening interface 12 through a lead, the positive electric interface 11, the opening interface 12 and the closing interface 13 are respectively connected with 1 test clip through insulated leads, and the combined part of the shifting cap 7 and the movable contact 8 can move transversely and be positioned at different positions so that different contacts of the movable contact 8 are in contact conduction and disconnection with the closing contact 9 and the opening contact 10.

In order to clamp the terminal strip by the test clamp, as shown in fig. 1, the clamping assembly includes 2 clamping legs 1, each of the 2 clamping legs 1 includes a clamping leg claw 101 and a clamping leg handle 102, a clamping leg connecting portion 103 is provided between the clamping leg claw 101 and the clamping leg handle 102, the 2 clamping legs 1 are rotatably connected through the clamping leg connecting portion 103, a supporting spring 2 is connected between the clamping leg handles 102 of the 2 clamping legs 1, and the clamping leg claw 101 is provided with a claw hook 105. The clamping claws 101 can effectively clamp the terminal strip through the elasticity of the supporting spring 2 and the rotatable connection of the clamping leg connecting part 103, and the claw hooks 105 can effectively prevent the clamping claws 101 from slipping off the terminal strip.

In order to achieve clamping adaptation to terminal rows of different widths, the prong claws 101 are provided with telescopic structures 104, as shown in fig. 1 and 4. To the terminal row of different width, through the extending structure portion 104 that presss from both sides claw 101, can effectively realize pressing from both sides claw 101 and arrange the centre gripping adaptation to not equidimension width terminal, this is extending structure portion 104 in reality includes outer festival and interior festival, and interior festival is through setting up the fretwork gap, and the clamping piece that makes fretwork gap both sides has elasticity and the inner wall elasticity of outer festival to paste tightly.

In order to adjust the angle of the test pin 4, as shown in fig. 1 and 3, the test pin 4 is connected with one of the clamping pin handles 102 through the pressure spring piece 3, and the test pin 4 is rotatably connected with the pressure spring piece 3. The rotatable connection of the test contact pin 4 and the pressure spring piece 3 is matched with the telescopic structure of the clamping claw 101, so that the angle of the test contact pin 4 can be adjusted, and the test contact pin 4 can be accurately inserted into a screw hole of the terminal.

In order to make the contact more reliable, the lower end of the test pin 4 is provided with a metal brush 5 at its head, as shown in fig. 1. The metal brush 5 is inserted into the screw hole of the terminal and contacts with the metal screw in the terminal, so that the contact is more reliable, and the conductive effect is better.

In order to realize positioning in different test items, as shown in fig. 5-7, test marks arranged transversely are arranged on one side of the top surface of the device shell 6, the test marks comprise neutral positions, closing position anti-tripping positions, opening positions and opening position anti-tripping positions, positioning grooves 601 corresponding to the positions of the test marks are arranged in the device shell 6, elastic positioning pieces 14 are arranged on the movable contact pieces 8, and when the movable contact pieces 8 move transversely, the elastic positioning pieces 14 can be matched with the positioning grooves 601 corresponding to the test marks for positioning. The position location when different test items are conveniently realized.

In order to realize the conduction and separation of different contact pins and the closing contact 9 and the opening contact 10, as shown in fig. 2, when the shift cap 7 is placed in the neutral test mark, the distance between the second contact pin 802 and the closing contact 9 is 1 unit, the distance between the third contact pin 803 and the opening contact 10 is 1 unit, the distance between the first contact pin 801 and the closing contact 9 is 2 units, and the distance between the fourth contact pin 804 and the opening contact 10 is 2 units. The accurate position distance setting of four contact pins and separating brake contact 10 and closing contact 9, accessible remove contact 8 and remove different positions, can effectively realize the switch on and the separation of different contact pins and closing contact 9 and separating brake contact 10, effectively realize various anti-bouncing tests.

In order to realize the lateral movement of the combination of the shift cap 7 and the moving contact 8, as shown in fig. 5 and 6, a guide rail groove 602 for the lateral movement of the moving contact 8 is provided in the device housing 6, and a lateral groove hole for the lateral movement of the shift cap 7 is provided in the top of the device housing 6. The transverse movement of the combined part of the gear shifting cap 7 and the movable contact piece 8 can be effectively realized.

To achieve the indication of the current test item, as shown in fig. 5, the side of the shift cap 7 facing the test mark is an indication triangular shape 701. The test device has an indicating function, and is convenient for operators to judge the current test items.

In order to conveniently identify different interfaces, the switching-off interface 12 is marked with green on the outer surface of the device housing 6, the switching-on interface 13 is marked with red on the outer surface of the device housing 6, and the positive interface 11 is marked with black on the outer surface of the device housing 6. The identification of different interfaces is conveniently realized, and the corresponding wiring of the insulated wire is convenient.

In order to improve the operation safety, the clamping feet 1 and the pressure spring pieces 3 are made of insulating plastics, the outer surfaces of the test contact pins 4 are made of insulating materials, the tail parts of the test contact pins 4 are provided with wire connecting ports, and the wire connecting ports are connected with the metal brush 5 through metal pieces; the device housing 6 is made of insulating plastic. The safety of operation can be effectively improved.

When the anti-jump test is carried out, the shift cap 7 is placed in a neutral position, the telescopic length of the test clamp foot clamping claw 101 is adjusted, the opening size of the test clamp foot clamping claw 101 is matched with the size of a terminal row, the foot clamping claws 101 of 3 test clamps respectively clamp the terminal rows corresponding to an opening terminal, a closing terminal and a positive terminal, the position angle of the test contact pin 4 is adjusted, the metal brush 5 of the test contact pin 4 reliably contacts with a metal screw in the terminal, and the test is started after the test clamps are installed.

When the on-position tripping prevention is carried out, firstly, the shifting cap 7 of the control device is shifted to a 'closing' identification position, at the moment, as shown in fig. 8, the second contact pin 802 of the movable contact piece 8 is communicated with the closing contact piece 9, a closing loop is communicated, the breaker is closed, after the breaker is closed and the energy storage is finished, the shifting cap 7 is shifted to the 'on-position tripping prevention' position, at the moment, as shown in fig. 9, the second contact pin 802 and the fourth contact pin 804 of the movable contact piece 8 are simultaneously communicated with the closing contact piece 9 and the opening contact piece 10 respectively, if the breaker is not closed again after opening, the tripping prevention function is correct, otherwise, the tripping prevention function is incorrect; when the tripping is performed, the shifting cap 7 of the control device is firstly shifted to the 'tripping' position, at this time, as shown in fig. 10, the third contact 803 of the mobile contact 8 is connected with the tripping contact 10, the tripping circuit is connected, after the breaker is tripped and the energy storage is completed, the shifting cap 7 is shifted to the 'tripping' position, at this time, as shown in fig. 11, the third contact 803 and the first contact 801 of the mobile contact 8 are simultaneously connected with the tripping contact 10 and the closing contact 9 respectively, if the breaker is switched on and off, the tripping function is correct, otherwise, the tripping function is incorrect.

This device is through removing movable contact 8 and fixing a position different experimental positions, makes movable contact 8's different contact feet and combined floodgate contact 9 and separating brake contact 10 contact and switch on and break off, carries out the jump test that prevents of difference, and the device overall structure is simple, and is small, light in weight, and easy operation is convenient, compares in traditional 2 people operation test, only needs 1 individual just can realize preventing jumping the test, can not appear contacting unreliable problem, has promoted experimental security and has reduced experimental operation number.

The above anti-tripping test device for circuit breaker shown in fig. 1-11 is a specific embodiment of the present invention, and it has been demonstrated that the substantial features and the progress of the present invention can be modified according to the actual use requirement, and the same modifications in the aspects of shape, structure, etc. are performed to the device, all within the protection scope of the present solution.

Claims (10)

1. The utility model provides a circuit breaker anti-bounce test device which characterized in that: including being used for the experimental clamp of tight connection on the terminal row and being used for the experimental operation control of circuit breaker anti-bounce, experimental clamp including clamping component with connect in the experimental contact pin (4) on clamping component, controlling means include device casing (6), dial cap (7), removal contact (8), closing contact (9) and separating brake contact (10) locate device casing (6) inside, the lower part transverse arrangement of removal contact (8) has 4 vertical contacts, according to from left to right be first contact (801), second contact (802), third contact (803), fourth contact (804) respectively, closing contact (9) and separating brake contact (10) are the perpendicular elastic contact of bottom that is fixed in device casing (6), closing contact (9) and separating brake contact (10) are connected and are fixed in the lower part and the closing contact of device casing (6) and are connected The device comprises a contact piece (9), a shifting cap (7), a shifting cap (10), a shifting contact piece (10), a switching-off interface (12), a switching-on interface (13), a positive electric interface (11), a switching-off interface (12), a switching-off interface (13), a moving contact piece (8), a switching-on contact piece (9) and a switching-off interface (13), wherein the contact piece (9) is positioned on the right side of a first contact pin (801), the shifting cap (7) is positioned on the left side of a fourth contact pin (804), the shifting cap (7) penetrates through a device shell downwards to be connected and fixed with the moving contact piece (8), the inner wall of one side of the device shell (6) is provided with the positive electric interface (11), the moving contact piece (8) is connected to the positive electric interface (11) through a lead, the switching-on contact piece (9) is correspondingly connected to the switching-on interface (13) through a lead, the switching-off contact piece (10) is correspondingly connected to the switching-off interface (12) through a lead, the positive electric interface (11), the switching-off interface (12) and the switching-on interface (13) are respectively connected to 1 test clip through an insulated lead, and the combined piece of the shifting cap (7) and the moving contact piece (8) can be moved transversely moved and positioned at different positions to enable different contact pins and different positions of the moving contact piece (8) The closing contact (9) and the opening contact (10) are in contact conduction and disconnection.

2. The circuit breaker anti-bounce test device of claim 1, characterized in that: the clamping assembly comprises 2 clamping feet (1), wherein the 2 clamping feet (1) comprise clamping feet claws (101) and clamping feet handles (102), clamping feet connecting parts (103) are arranged between the clamping feet claws (101) and the clamping feet handles (102), the 2 clamping feet (1) are rotatably connected through the clamping feet connecting parts (103), supporting springs (2) are connected between the clamping feet handles (102) of the 2 clamping feet (1), and the clamping feet claws (101) are provided with claw hooks (105).

3. The circuit breaker anti-bounce test device of claim 2, characterized in that: the clamping claw (101) is provided with a telescopic structure part (104).

4. The circuit breaker anti-bounce test device of claim 3, wherein: the test contact pin (4) is connected with one of the clamping foot handles (102) through the pressure spring piece (3), and the test contact pin (4) is rotatably connected with the pressure spring piece (3).

5. The circuit breaker anti-bounce test device of claim 4, wherein: the head of the lower end inserting needle of the test inserting needle (4) is provided with a metal brush (5).

6. The circuit breaker anti-bounce test device of claim 1, characterized in that: device casing (6) top surface one side be equipped with transverse arrangement's experimental sign, experimental sign include neutral, combined floodgate, close the position and prevent jumping, separating brake and separating the position and prevent jumping, device casing (6) in be equipped with positioning groove (601) that correspond with each experimental sign position, mobile contact (8) on be equipped with elastic positioning element (14), when mobile contact (8) lateral shifting, elastic positioning element (14) can match the location with positioning groove (601) that each experimental sign corresponds.

7. The circuit breaker anti-bounce test device of claim 6, characterized in that: when the shift cap (7) is arranged on the neutral test mark, the distance between the second contact pin (802) and the closing contact piece (9) is 1 unit, the distance between the third contact pin (803) and the opening contact piece (10) is 1 unit, the distance between the first contact pin (801) and the closing contact piece (9) is 2 units, and the distance between the fourth contact pin (804) and the opening contact piece (10) is 2 units.

8. The circuit breaker anti-bounce test device of claim 7, wherein: the device is characterized in that a guide rail groove (602) used for moving the contact piece (8) to move transversely is arranged in the device shell (6), and a transverse groove hole used for moving the gear shifting cap (7) transversely is formed in the top of the device shell (6).

9. The circuit breaker anti-bounce test device of claim 8, wherein: one side of the gear shifting cap (7) facing the test mark is in an indicating triangle shape (701).

10. The circuit breaker anti-bounce test device of claim 1, characterized in that: the switching-off interface (12) adopts green marks on the outer surface side of the device shell (6), the switching-on interface (13) adopts red marks on the outer surface side of the device shell (6), and the positive interface (11) adopts black marks on the outer surface side of the device shell (6).

Images