Input switching device for time-sharing acquisition of double-path small signals

Abstract

The invention belongs to the technical field of data acquisition, and discloses an input switching device for time-sharing acquisition of double-path small signals. The input switching device for time-sharing acquisition of the double-path small signals comprises an input module A, an input module B, a signal switching module, an output module and a control module, and is used for switching the two paths of signals. According to the input switching device for time-sharing acquisition of the double-path small signals, in a signal loop, two through-flow loops which are opposite in direction and approximately equal in area size are designed, interference of an electromagnetic field and the like of the switching device on the measured small signals is reduced, the purpose of improving the signal-to-noise ratio is achieved, switching interference is small, the speed is high, and time-sharing acquisition of the double-path small signals is achieved. Technical support is provided for multi-path switching time-sharing acquisition of small signals, the requirement for high-precision small signal switching can be met, and engineering practical value is achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of data acquisition, and particularly relates to an input switching device for dual-channel small-signal time-sharing acquisition. Background Art

[0002] Signal acquisition, processing, and analysis are important contents in the field of signal processing. Among them, signal acquisition is the basic work. In the actual data acquisition process, signal multiplexing switching acquisition is often used. For data acquisition occasions with low signal voltage and high precision requirements, higher requirements are imposed on signal multiplexing switching acquisition. Using an instrument relay to switch signals is a common method. When the relay switches, it is necessary to supply power to the electromagnet coil to generate an electromagnetic field, which will superimpose interference on the signal.

[0003] Currently, there is an urgent need to develop an input switching device for dual-channel small-signal time-sharing acquisition. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide an input switching device for dual-channel small-signal time-sharing acquisition.

[0005] The input switching device for dual-channel small-signal time-sharing acquisition of the present invention includes an input module A, an input module B, a signal switching module, an output module, and a control module; The input signal A is connected to the input module A by two wires, and the input signal B is connected to the input module B by two wires; the signal module B is connected to the signal switching module by two wires to provide the first input signal for the signal switching module, and the signal module B is connected to the signal switching module by two wires to provide the second input signal for the signal switching module; The signal switching module is connected to the output module by two wires, and either the signal module A or the signal module B is connected to the output module; the output module is connected to the measuring device by two wires; The control signal is connected to the control module by two wires; the control module is connected to the signal switching module by two wires and is used to control the signal switching module to select either the signal module A or the signal module B to be connected to the output module.

[0006] Further, the signal switching module includes an input normally closed module, an input normally open module, an input common module, an output common module, an output normally closed module, an output normally open module, and a switching device; The switching device is used to select the two-wire connection between the input normally closed module and the input common module, or the two-wire connection between the input normally open module and the input common module; at the same time, the switching device is used to select the two-wire connection between the output common module and the output normally closed module, or the two-wire connection between the output common module and the output normally open module; the input common module is connected to the output common module by two wires; The input module A is connected to the input normally-closed module; the input module B is connected to the input normally-open module; the control module is connected to the switching device; the output normally-closed module and the output normally-open module are connected in parallel in two lines and then connected to the output common module; According to the right-hand rule, the current loop formed by the two-line connection from the input normally-open module to the input common module and the current loop formed by the two-line connection from the output common module to the output normally-open module are opposite in direction and equal in area.

[0007] In the signal circuit, the input switching device for dual-channel small-signal time-sharing acquisition of the present invention reduces the interference of the electromagnetic field of the switching device on the measured small signal by designing two current-carrying loops with opposite directions and approximately equal area sizes, achieving the purpose of improving the signal-to-noise ratio. The switching interference is small and the speed is fast, providing technical support for the multi-channel switching time-sharing acquisition of small signals, being able to meet the high-precision small-signal switching requirements, and having engineering practical value. Brief Description of the Drawings

[0008] Figure 1 It is a schematic structural diagram of the input switching device for dual-channel small-signal time-sharing acquisition of the present invention; Figure 2 is Figure 1 the corresponding physical implementation schematic diagram; Figure 3 It is a schematic diagram of a control method for implementing a 4-channel relay.

[0009] In the figure, 1. Input module A, 2. Input module B, 3. Signal switching module, 4. Output module, 5. Control module, 6. Input signal A, 7. Input signal B, 8. Measuring device, 9. Control signal; 301. Input normally-closed module, 302. Input normally-open module, 303. Input common module, 304. Output common module, 305. Output normally-closed module, 306. Output normally-open module, 307. Switching device. Detailed Description of the Preferred Embodiment

[0010] The present invention will be described in detail below with reference to the drawings and embodiments.

[0011] As Figure 1 shown, the input switching device for dual-channel small-signal time-sharing acquisition of the present invention includes an input module A1, an input module B2, a signal switching module 3, an output module 4, and a control module 5; The input signal A6 is connected to the input module A1 by two lines, and the input signal B7 is connected to the input module B2 by two lines; the signal module B1 is connected to the signal switching module 3 by two lines to provide the first input signal for the signal switching module 3, and the signal module B2 is connected to the signal switching module 3 by two lines to provide the second input signal for the signal switching module 3; The signal switching module 3 and the output module 4 are connected by two wires. The signal module A1 or the signal module B2 is connected to the output module 4. The output module 4 and the measuring device 8 are connected by two wires. The control signal 9 and the control module 5 are connected by two wires. The control module 5 and the signal switching module 3 are connected by two wires, and are used to control the signal switching module 3 to select the signal module A1 or the signal module B2 to be connected to the output module 4.

[0012] Furthermore, the signal switching module 3 includes an input normally closed module 301, an input normally open module 302, an input common module 303, an output common module 304, an output normally closed module 305, an output normally open module 306, and a switching device 307. The switching device 307 is used to select the two-wire connection between the input normally closed module 301 and the input common module 303, or the two-wire connection between the input normally open module 302 and the input common module 303. At the same time, the switching device 307 is used to select the two-wire connection between the output common module 304 and the output normally closed module 305, or the two-wire connection between the output common module 304 and the output normally open module 306. The input common module 303 and the output common module 304 are connected by two wires. The input module A1 is connected to the input normally closed module 301. The input module B2 is connected to the input normally open module 302. The control module 5 is connected to the switching device 307. The output normally closed module 305 and the output normally open module 306 are connected in parallel by two wires and then connected to the output common module 4. According to the right-hand rule, the current loop of the two-wire connection from the input normally open module 302 to the input common module 303 and the current loop of the two-wire connection from the output common module 304 to the output normally open module 306 are opposite in direction and equal in area.

[0013] Embodiment: When implementing Figure 1 the function, corresponding components or software are utilized. The specific components or software can be seen in Figure 2 、 Figure 3Specifically, input module A1 corresponds to input connector A, input module B2 corresponds to input connector B, signal switching module 3 corresponds to a 4-channel relay, output module 4 corresponds to an output connector, control module 5 corresponds to a control connector, input signal A6 corresponds to measured signal 1, input signal B7 corresponds to measured signal 2, measuring device 8 corresponds to a voltage acquisition system, and control signal 9 corresponds to a selection signal. Input normally closed module 301 corresponds to the normally closed contacts of channels 1 and 2, output normally open module 302 corresponds to the normally open contacts of channels 1 and 2, input common module 303 corresponds to the common contacts of channels 1 and 2, output common module 304 corresponds to the common contacts of channels 3 and 4, output normally closed module 305 corresponds to the normally closed contacts of channels 3 and 4, output normally open module 306 corresponds to the normally open contacts of channels 3 and 4, and switching device 307 corresponds to a control coil.

[0014] Among them, channels 1, 2, 3, and 4 are 4 groups of contacts arranged in sequence by a 4-channel relay. The common contact of channel 1 is connected to the common contact of channel 3 by a single wire, and the common contact of channel 4 is connected to the common contact of channel 2 by a single wire. The current flows through channels 1, 3, 4, and 2 in sequence, and the vector area is approximately 0.

[0015] Although the embodiments of the present invention have been disclosed as above, they are not limited to the applications listed in the specification and embodiments. For those skilled in the art, without departing from the principle of the present invention, all the features disclosed in the present invention, or all the steps in the disclosed methods or processes, except for mutually exclusive features and / or steps, can be combined in any way. The present invention is not limited to the specific details and the illustrated and described examples here.

Claims

1. An input switching device for dual-channel small-signal time-division acquisition, characterized in that The described input switching device includes an input module A (1), an input module B (2), a signal switching module (3), an output module (4), and a control module (5); The input signal A (6) is connected to the input module A (1) by two wires, and the input signal B (7) is connected to the input module B (2) by two wires; The signal module B (1) is connected to the signal switching module (3) by two wires to provide the first input signal to the signal switching module (3), and the signal module B (2) is connected to the signal switching module (3) by two wires to provide the second input signal to the signal switching module (3); The signal switching module (3) is connected to the output module (4) by two wires, and either the signal module A (1) or the signal module B (2) is connected to the output module (4); The output module (4) is connected to the measuring device (8) by two wires; The control signal (9) is connected to the control module (5) by two wires; The control module (5) is connected to the signal switching module (3) by two wires and is used to control the signal switching module (3) to select either the signal module A (1) or the signal module B (2) to be connected to the output module (4).

2. The input switching device for dual-channel small-signal time-division acquisition according to claim 1, wherein The described signal switching module (3) includes an input normally closed module (301), an input normally open module (302), an input common module (303), an output common module (304), an output normally closed module (305), an output normally open module (306), and a switching device (307); The switching device (307) is used to select the two-wire connection between the input normally closed module (301) and the input common module (303), or the two-wire connection between the input normally open module (302) and the input common module (303); At the same time, the switching device (307) is used to select the two-wire connection between the output common module (304) and the output normally closed module (305), or the two-wire connection between the output common module (304) and the output normally open module (306); The input common module (303) is connected to the output common module (304) by two wires; The input module A (1) is connected to the input normally closed module (301); The input module B (2) is connected to the input normally open module (302); The control module (5) is connected to the switching device (307); After the output normally closed module (305) and the output normally open module (306) are connected in parallel by two wires, they are connected to the output common module (4); According to the right-hand rule, the current loop of the two-wire connection from the input normally open module (302) to the input common module (303) and the current loop of the two-wire connection from the output common module (304) to the output normally open module (306) are opposite in direction and equal in area.

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