Train network fault detection tool and detection method
Technical Field
The invention relates to the field of rail transit, in particular to a train network fault detection tool and a train network fault detection method.
Background
The statements in this section merely provide background information related to the present disclosure and may not necessarily constitute prior art.
In the static debugging process of the metro vehicle, if the equipment works normally, but the icon corresponding to the working state of the equipment on the network display screen is still gray, the network signal transmission is indicated to be faulty, and in order to detect the network signal fault, the following method is generally adopted for judging:
(1) measuring the terminal resistance of the train-level network after the grouping by a worker;
(2) comparing the measured resistance value with the terminal resistance value of the train-level network, and if the measured value is smaller than the given value, indicating that the terminal resistance is not sheared;
(3) and the connectors of the whole train are disassembled and inspected one by a worker.
The inventor finds that the following defects exist according to the existing detection method:
(1) because the vehicles are grouped, the whole train connector is disassembled and inspected according to the existing method, the cutting-out condition of the resistance bridge is checked one by one, the workload is extremely high, the efficiency is extremely low, and the internal resistance of the equipment for measuring the resistance is relatively high, so that the method is not suitable for measuring the resistance value of the communication cable.
(2) When the personnel performs the disassembly and inspection in the debugging process, the personnel adopts a visual method to operate, and is easily influenced by personal factors and environmental factors.
(3) The connector is repeatedly disassembled and assembled, so that the assembling quality of the connector is easily affected, and the service life of the connector is affected.
Disclosure of Invention
Aiming at the defects of the prior art, the first aim of the invention is to provide a train network fault detection tool, which does not judge through the measurement of resistance value any more, compares and outputs the input voltages of two input ends through a voltage comparator, has high detection speed and effectively reduces the workload of constructors.
The second object of the invention is to provide a train network fault detection method, which is convenient to operate, and constructors do not need to master a large amount of resistance data, so that the intelligent and humanized degree is greatly improved.
In order to achieve the above object, the present invention is realized by the following technical scheme:
the utility model provides a train network fault detection frock, includes voltage comparator, and terminal resistance selection circuit is connected to one of them input of voltage comparator, and measuring circuit is connected to another input, and measuring circuit inserts the connector, and terminal resistance selection circuit includes many resistance selection module, and terminal resistance selection circuit can be to voltage comparator input the voltage value that the terminal resistance value of different modules of bicycle corresponds, and voltage comparator is through comparing this voltage value and measuring circuit input's voltage value size, realizes the judgement whether cuts out the connector resistance bridge.
According to the train network fault detection tool, the multi-resistor selection module comprises the first switch and the terminal resistor values corresponding to the modules of the single train, and the first switch can be connected with different terminal resistor values.
According to the train network fault detection tool, the terminal resistor selection circuit further comprises the third resistor connected with the multi-resistor selection module, the third resistor is connected with an external power supply, a positive feedback resistor is arranged between the third resistor and the output end of the voltage comparator, and the voltage comparator has hysteresis characteristics through the arrangement of the positive feedback resistor, so that the anti-interference capability of the detection tool is enhanced; and a pull-up resistor is arranged between the external power supply and the output end of the voltage comparator, and the voltage clamping function is achieved through the arrangement of the pull-up resistor, so that the high level of the output end can reach a set value.
According to the train network fault detection tool, the forward input end of the voltage comparator is connected with the terminal resistor selection circuit, and the reverse input end of the voltage comparator is connected with the measurement circuit.
According to the train network fault detection tool, the positive input end of the voltage comparator is connected to one side, far away from the multi-resistor selection module, of the third resistor in the terminal resistor selection circuit, and the third resistor plays a role in fusing protection.
According to the train network fault detection tool, the first switch is provided with the first grounding wire clamp at one side far away from the resistance selection module, and the first grounding wire clamp is used for being connected with the body of the rail transit vehicle so as to achieve grounding.
According to the train network fault detection tool, the fifth resistor and the sixth resistor are arranged on the measuring circuit, the fifth resistor is the internal resistor of the connector, and the fifth resistor is connected to the external power supply.
According to the train network fault detection tool, the reverse input end of the voltage comparator is connected between the fifth resistor and the sixth resistor in the measuring circuit, and the sixth resistor plays a role in voltage division.
According to the train network fault detection tool, one side of the sixth resistor in the measurement circuit is connected with the second grounding wire clamp, and the second grounding wire clamp is used for being connected with a vehicle body of a rail transit vehicle so as to achieve grounding.
According to the train network fault detection tool, the output end of the voltage comparator is connected with the display part through the first resistor, and the display part is a display lamp.
In a second aspect, the invention further provides a train network fault detection method, which comprises any one of the train network fault detection tools.
A train network fault detection method comprises the following steps:
extracting connectors corresponding to the modules of the bicycle;
according to a bicycle module to be detected, connecting a terminal resistor corresponding to the module into a terminal resistor selection circuit;
the connector of the bicycle module to be detected is connected into the detection circuit;
and judging whether the termination resistor is sheared or not according to the output condition of the output end of the voltage comparator.
The beneficial effects of the invention are as follows:
1) According to the invention, the voltage values corresponding to the terminal resistances of different modules of the bicycle can be obtained through the terminal resistance selection circuit, and the voltage comparator is used for comparing the resistance values with the voltage values of the measuring circuit where the connector is positioned and displaying the voltage values through the display part, so that the judgment on whether the resistor bridge of the connector is sheared or not is realized.
2) According to the invention, a large amount of data can be stored through the arrangement of the voltage comparator, a constructor does not need to master the data, the cutting-out condition of the connector resistor can be judged directly through the indicating component, and the intellectualization and humanization of train network fault detection are greatly improved.
3) According to the invention, through the arrangement of the positive feedback resistor, the voltage comparator has hysteresis characteristics, and the anti-interference capability of the detection tool is enhanced.
4) The invention ensures that the high level of the output end can reach the set value through the setting of the pull-up resistor.
Drawings
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention.
Fig. 1 is a schematic diagram of a train network fault detection tool according to one or more embodiments of the present invention.
Fig. 2 is a flow diagram of a method of train network failure detection in accordance with one or more embodiments of the present invention.
In the figure: the mutual spacing or dimensions are exaggerated for the purpose of showing the positions of the various parts, and the schematic illustration is only schematic.
Detailed Description
It should be noted that the following detailed description is illustrative and is intended to provide further explanation of the invention. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.
It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of exemplary embodiments according to the present invention. As used herein, the singular forms also are intended to include the plural forms unless the present invention clearly dictates otherwise, and furthermore, it should be understood that when the terms "comprise" and/or "include" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof;
for convenience of description, the words "upper", "lower", "left" and "right" in the present invention, if they mean only that the directions are consistent with the upper, lower, left, and right directions of the drawings per se, and do not limit the structure, only for convenience of description and simplification of the description, but do not indicate or imply that the apparatus or element to be referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present invention.
Term interpretation section: the term "connected" and other terms are to be construed broadly in the present invention, and may be, for example, fixedly connected, detachably connected, or integrally formed; the terms are used herein as specific meanings as understood by those of ordinary skill in the art, and are not limited to the following terms.
As described in the background art, the problem of large workload of network fault detection exists in the prior art, and in order to solve the technical problems, the invention provides a train network fault detection tool and a train network fault detection method.
Example 1
In an exemplary embodiment of the present invention, referring to fig. 1, a train network fault detection tool may be used for a train MVB network, where the detection tool includes a voltage comparator, and the voltage comparator has two input terminals and one output terminal, where one input terminal is connected to a terminal resistor selection circuit, and the other input terminal is connected to a measurement circuit, and specifically in this embodiment, a forward input terminal of the voltage comparator is connected to the terminal resistor selection circuit, and a reverse input terminal is connected to the measurement circuit.
The output end of the voltage comparator is connected with the display component through a first resistor R1, and the display component is positionedThe voltage of the output end is U o The method comprises the steps of carrying out a first treatment on the surface of the In some examples, the display component is an indicator light.
The terminal resistor selection circuit comprises a multi-resistor selection module, the multi-resistor selection module comprises a first switch and terminal resistor values corresponding to the modules of the bicycle, specifically, R7-Rn (n is a natural number) respectively correspond to the terminal resistor values corresponding to the different modules of the bicycle (for example, the terminal resistor values of a door control, an air conditioner, a traction inverter and the like), and the terminal resistor values corresponding to the modules of the bicycle are calculated according to different bicycle types.
Further, the first switch can be connected with different terminal resistance values, and the first switch is connected with a first ground wire clamp which can be connected with a vehicle body.
The terminal resistor selection circuit further comprises a third resistor R3 connected with the multi-resistor selection module, the third resistor is connected with an external power supply, a positive feedback resistor is arranged between the third resistor and the output end of the voltage comparator, the positive feedback resistor is the second resistor R2, and the voltage comparator has hysteresis characteristics through the arrangement of the positive feedback resistor, so that the anti-interference capability of the detection tool is enhanced; and a pull-up resistor is arranged between the external power supply and the output end of the voltage comparator, and the voltage clamping function is achieved through the arrangement of the pull-up resistor, so that the high level of the output end can reach a set value.
And the second switch is arranged between the external power supply and the detection circuit and between the external power supply and the terminal resistor selection circuit, it can be understood that the external power supply selects a 9V laminated battery.
The pull-up resistor is a fourth resistor R4, the high level of the output end can reach the voltage 9V of the external power supply through the arrangement of the pull-up resistor, the pull-up resistor is equivalent to the voltage stabilizing effect of the output end of the voltage comparator, if the voltage stabilizing level of the voltage stabilizing tube is +/-9V, the low level of the pull-up resistor is zero when the stack battery is selected; the resistance of the pull-up resistor is generally 1KΩ -10KΩ, the output current of the laminated battery is extremely small, the voltage division on the pull-up resistor is negligible, so the high level can be regarded as 9V, and correspondingly, the voltage U of the output terminal is enabled by the comparison of the forward input terminal and the reverse input terminal of the voltage comparator 0 Can only be 9V or lowLevel 0V.
The third resistor in the terminal resistor selection circuit has smaller resistance value and plays a role in fusing protection, the positive input end of the voltage comparator is connected to one side of the third resistor in the terminal resistor selection circuit far away from the multi-resistor selection module, and two parallel diodes D which can be connected into a vehicle body are arranged on the connecting line 1 And D 2 The two diodes are reversely arranged to play a role in stabilizing voltage, and the input voltage of the forward input end of the voltage comparator is U N 。
Regarding the measuring circuit, a fifth resistor R5 and a sixth resistor R6 are arranged in the measuring circuit, the fifth resistor is the internal resistor of the connector of the existing rail transit vehicle, such as DB9-MVB connector (D-SUB 9 needle connector, DB9-MVB connector is called because the connector is used in MVB network), the DB9-MVB connector is connected into the measuring circuit through a positive meter pen and a negative meter pen, the sixth resistor plays the roles of current limiting and voltage dividing, one end of the fifth resistor in the measuring circuit is connected with an external power supply, one end of the sixth resistor is connected with a second grounding wire clamp, the grounding is carried out through the second grounding wire clamp, the reverse input end of the voltage comparator is connected between the fifth resistor and the sixth resistor in the measuring circuit, and the input voltage of the reverse input end of the voltage comparator is U I 。
According to the detection tool, by utilizing the principle of the hysteresis voltage comparator, the voltage values corresponding to the terminal resistances of the modules of different bicycles are compared through the detection tool, and the judgment is carried out through the indicator lamp at the output end of the voltage comparator, so that the judgment on whether the resistance bridge of the DB9-MVB connector is sheared or not is realized.
Furthermore, the voltage comparator selects the Lm339 integrated circuit board, the storage space of the voltage comparator chip is large, the terminal resistance values of different modules of different vehicle types can be stored, constructors do not need to master a large amount of resistance data, the vehicle type and the measuring module are only needed to be selected during construction, the resistance trimming condition of the DB9-MVB connector can be judged according to whether the indicator light on the tool is on, and the intelligent and humanized degree is greatly improved.
In addition, it should be explained that the sizes of the first resistor, the second resistor, the third resistor, the fourth resistor and the sixth resistor can be selected according to actual needs, and the first ground clamp and the second ground clamp are all conventional common ground clamps.
Example two
A train network fault detection method is shown with reference to FIG. 2, and includes a train network fault detection tool as described in the first embodiment.
Above-mentioned detection frock, when using, include following content:
according to the wiring diagram, locating the positions of the DB9-MVB connectors (DB 9 connectors in the drawing) of the modules of the bicycle and pulling out the DB9-MVB connectors so that the modules of the bicycle are independent;
starting the detection tool, and connecting terminal resistors corresponding to different modules of a bicycle into a terminal resistor selection circuit through a first switch according to the bicycle module to be detected to form a reference voltage U Ref The reference voltage becomes the input voltage U of the positive input end of the voltage comparator after passing through the third resistor N Considering that the third resistance is small, the reference voltage U Ref Is directly participatable in comparison;
inserting a detection circuit of the detection tool into a male pin or a female pin of the DB9-MVB connector, butting the male pin or the female pin of the DB9-MVB connector with the male pin or the female pin of the bicycle DB9-MVB connector, and simultaneously, respectively connecting a first grounding wire clamp and a second grounding wire clamp of the detection tool with a bicycle body;
switching on an external power supply, if the terminal resistance of each module of the bicycle is not cut off, U I ﹥U N ,U 0 At low level, the indicator is not on, if the termination resistor is cut off, U I ﹤U N ,U 0 At a high level, the indicator lights are illuminated, proving that the termination resistor has been cut.
The above description is only of the preferred embodiments of the present invention and is not intended to limit the present invention, but various modifications and variations can be made to the present invention by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.