A pointer type insulation resistance meter

Abstract

The utility model discloses a pointer type insulation resistance meter, which aims to solve the problem of various types and poor flexibility caused by the fixed alarm range through panel printing in the prior art. The device comprises a dial, a pointer movement, a white LED backlight plate and a control unit. The innovation is that a mechanical dynamic color display system composed of an annular light-transmitting sheet assembly and a gear and rack driving mechanism is additionally provided. The annular light-transmitting sheet assembly is seamlessly spliced by a semicircular red light-transmitting sheet and a semicircular green light-transmitting sheet and is rotatably arranged between the backlight plate and the dial. The driving mechanism comprises an arc-shaped rack fixed to the inner side of the light-transmitting sheet, a driving gear engaged with the rack and a micro motor. The control unit can accurately control the rotation of the annular light-transmitting sheet by driving the motor, so that the red-green boundary line is aligned with any set alarm value on the dial. Thus, under the white backlight transmission, a clear and sharp red-green boundary line with a variable position is formed, and dynamic and intuitive indication of the alarm range is realized.

Description

Technical Field

[0001] This utility model relates to the field of physics, and more particularly to electrical measuring instruments, especially to the indicating structure of a pointer-type insulation resistance meter, specifically a pointer-type insulation resistance meter. Background Technology

[0002] A pointer-type insulation resistance meter is a common tool for measuring the insulation resistance of electrical equipment. It indicates the resistance value by the deflection of the pointer on the arc-shaped scale. In many industrial applications, a safety threshold (alarm value) needs to be set. When the insulation resistance is lower than this value, it is considered unqualified and an early warning is required.

[0003] In existing technologies, alarm indication is achieved by using color areas on a fixed printed panel. During instrument manufacturing, different colored areas are directly printed on the dial scale according to customer requirements (e.g., red for the 0-2MΩ range and green for above 2MΩ). The main drawbacks of this method are: diverse customer needs lead to a wide variety of panel types, complex production, stock preparation, and inventory management, long lead times, low efficiency, and once shipped, the alarm range cannot be changed, resulting in extremely poor flexibility.

[0004] Therefore, there is an urgent need for an indication scheme that can flexibly set alarm ranges and provide clear and unambiguous visual demarcation lines. Utility Model Content

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a novel and clearly marked pointer-type insulation resistance meter dynamic alarm range indicator device. It can flexibly set alarm values ​​through a program like an electronic solution, and can also provide a sharp and clear dividing line like mechanical printing, fundamentally solving the problem of ambiguous alarm boundaries.

[0006] To achieve the above objectives, this utility model provides a pointer-type insulation resistance meter, which includes an instrument housing, a dial mounted on the housing, a control unit disposed below the dial, and also includes a white LED backlight panel and a mechanical dynamic color display system;

[0007] The dial has an arc-shaped display window, and resistance scale is printed inside the arc-shaped display window;

[0008] The white LED backlight panel is fixedly installed below the dial to provide uniform backlight illumination;

[0009] The mechanical dynamic color display system includes an annular light-transmitting sheet assembly and a gear and rack drive mechanism for driving the annular light-transmitting sheet assembly to rotate. The annular light-transmitting sheet assembly is rotatably disposed between the white LED backlight panel and the dial. The annular light-transmitting sheet assembly is arranged inside the arc-shaped display window. The annular light-transmitting sheet assembly is formed by seamlessly splicing semi-circular red light-transmitting sheets and semi-circular green light-transmitting sheets along the diameter direction to form a complete annular sheet. The gear and rack drive mechanism is controlled by the control unit and is used to drive the annular light-transmitting sheet assembly to rotate around its center axis.

[0010] Furthermore, this utility model provides a pointer-type insulation resistance meter, wherein the gear and rack drive mechanism includes an arc-shaped rack, a drive gear, and a micro motor; the arc-shaped rack is fixedly installed on the inner circumferential surface of the annular light-transmitting sheet assembly, the teeth of the arc-shaped rack face the center, and the center of curvature of the arc-shaped rack coincides with the center of the annular light-transmitting sheet assembly; the micro motor is fixed inside the instrument housing; the drive gear is sleeved on the output shaft of the micro motor, and the drive gear meshes with the arc-shaped rack.

[0011] Furthermore, this utility model provides a pointer-type insulation resistance meter, wherein the micro motor is a stepper motor or a servo motor.

[0012] Furthermore, the present invention provides a pointer-type insulation resistance meter, which further includes a guide rail limiting structure for supporting and guiding the smooth rotation of the annular light-transmitting sheet assembly; the guide rail limiting structure includes an annular groove, the groove opening of the annular groove pointing to the center, the annular groove being fixed to the inner wall of the outer shell, and the annular light-transmitting sheet assembly being fitted into the annular groove.

[0013] Furthermore, this utility model provides a pointer-type insulation resistance meter, wherein a reduction gear set is provided between the drive gear and the output shaft of the micro motor to increase torque and improve rotational accuracy.

[0014] Furthermore, the present invention provides a pointer-type insulation resistance meter, wherein the red and green light-transmitting sheets are components made of colored uniform acrylic or polycarbonate material, and a black opaque sheet is embedded at the joint between the red and green light-transmitting sheets.

[0015] Compared with the prior art, the pointer-type insulation resistance meter of this utility model has the following advantages:

[0016] 1. The alarm boundary is absolutely clear: The physical seam of the ring-shaped light-transmitting sheet serves as the dividing line between the red and green areas. This is a real, sharp line that completely eliminates the ambiguity caused by the mixing of pure electronic light and color, making the alarm threshold clear at a glance and greatly improving the accuracy and speed of interpretation.

[0017] 2. High flexibility and versatility: The alarm range can be set arbitrarily within the instrument's range through the program, eliminating the need to print different specifications of panels for different customers. One set of hardware can meet all needs, greatly simplifying production, inventory management and after-sales service.

[0018] 3. Reliable structure and long service life: The gear and rack transmission and guide rail limit adopted are mature mechanical structures with high precision, good wear resistance and stable operation;

[0019] 4. Professional and aesthetically pleasing display effect: The white backlight shines through the uniformly colored light-transmitting sheet, presenting full and even red and green areas. Combined with the clear black opaque sheet, the overall display effect is very professional and intuitive.

[0020] 5. Excellent user experience: Users only need to set the alarm value, and the device can automatically align the clear dividing line with the target scale. The operation is simple, the results are intuitive, and it effectively avoids misjudgment caused by blurred boundaries. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the structure of a pointer-type insulation resistance meter according to the present invention;

[0022] Figure 2 This is a schematic diagram of the internal structure of a pointer-type insulation resistance meter according to the present invention;

[0023] Figure 3 This is an exploded view of the circular heat sink structure of a pointer-type insulation resistance meter according to this utility model;

[0024] Figure 4 for Figure 3 Schematic diagram of the structure with changing perspective.

[0025] The components include: 1. Outer shell; 2. Dial; 3. White LED backlight panel; 4. Curved display window; 5. Resistance scale; 6. Red light-transmitting sheet; 7. Green light-transmitting sheet; 8. Black opaque sheet; 9. Curved rack; 10. Drive gear; 11. Micro motor; 12. Reduction gear set; 13. Annular groove. Detailed Implementation

[0026] The technical solution of this utility model will be clearly and completely described below with reference to the embodiments and accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0027] In the description of this utility model, it should be noted that the terms "upper," "lower," "inner," "outer," "front end," "rear end," "both ends," "one end," and "the other end," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0028] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installed," "equipped with," and "connected," etc., should be interpreted broadly. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0029] like Figures 1-4 As shown, this embodiment provides a pointer-type insulation resistance meter, which includes an instrument housing 1, a dial 2 mounted on the housing 1, a control unit disposed below the dial 2, and also includes a white LED backlight 3 and a mechanical dynamic color display system;

[0030] The dial 2 has an arc-shaped display window 4, and resistance scale 5 is printed inside the arc-shaped display window 4;

[0031] The white LED backlight panel 3 is fixedly installed below the dial 2 to provide uniform backlight illumination;

[0032] The mechanical dynamic color display system includes an annular light-transmitting sheet assembly and a gear and rack drive mechanism for driving the annular light-transmitting sheet assembly to rotate. The annular light-transmitting sheet assembly is rotatably disposed between the white LED backlight panel 3 and the dial 2. The annular light-transmitting sheet assembly is arranged inside the arc-shaped display window 4. The annular light-transmitting sheet assembly is formed by seamlessly splicing a semi-circular red light-transmitting sheet 6 and a semi-circular green light-transmitting sheet 7 along the diameter direction to form a complete annular sheet. The red light-transmitting sheet 6 and the green light-transmitting sheet 7 are components made of colored uniform acrylic or polycarbonate material. A black opaque sheet 8 is embedded at the splicing seam of the red light-transmitting sheet 6 and the green light-transmitting sheet 7. The gear and rack drive mechanism is controlled by the control unit and is used to drive the annular light-transmitting sheet assembly to rotate around its center axis.

[0033] The gear and rack drive mechanism includes an arc-shaped rack 9, a drive gear 10, and a micro motor 11. The arc-shaped rack 9 is fixedly mounted on the inner circumferential surface of the annular light-transmitting sheet assembly, with the teeth of the arc-shaped rack 9 facing the center of the circle, and the center of curvature of the arc-shaped rack 9 coinciding with the center of the annular light-transmitting sheet assembly. The micro motor 11 is fixed inside the instrument housing 1. The drive gear 10 is sleeved on the output shaft of the micro motor 11, and the drive gear 10 meshes with the arc-shaped rack 9. A reduction gear set 12 is provided between the drive gear 10 and the output shaft of the micro motor 11 to increase torque and improve rotational accuracy. In this embodiment, the micro motor 11 is a stepper motor or a servo motor.

[0034] As a preferred embodiment, it further includes a guide rail limiting structure for supporting and guiding the smooth rotation of the annular light-transmitting sheet assembly; the guide rail limiting structure includes an annular groove 13, the groove opening of the annular groove 13 points to the center, the annular groove 13 is fixed to the inner wall of the outer shell 1, and the annular light-transmitting sheet assembly is fitted into the annular groove 13.

[0035] The control unit has a pre-stored correspondence between different alarm range settings and the rotation angle of the micro motor 11. When an alarm setting command is received, the control unit simultaneously performs the following two operations:

[0036] a. Control the white LED backlight panel 3 to light up;

[0037] b. Calculate the required rotation angle of the micro motor 11 according to the correspondence, and drive the micro motor 11 to rotate, thereby driving the annular light-transmitting sheet assembly to rotate through the gear and rack drive mechanism until its red-green boundary line is aligned with the target resistance scale 5 on the dial 2.

[0038] Specifically: This embodiment includes an instrument housing 1, with a control unit fixedly installed on the bottom or side wall of the housing 1. A white LED backlight panel 3 is directly fixed inside the housing 1, located below the dial 2. An annular groove 13 is installed above the backlight panel, which is typically made of engineering plastic. The outer edge of the annular light-transmitting sheet assembly is fitted into the annular groove 13. In this embodiment, the annular light-transmitting sheet assembly is formed by ultrasonically welding a semi-circular red uniform light acrylic sheet and a semi-circular green uniform light acrylic sheet. A black [unclear] sheet is embedded at the seam. The opaque sheet 8 has an arc-shaped rack 9 fixedly installed on the inner circumferential surface of the annular light-transmitting sheet assembly by adhesive or snap-fit. The drive gear 10 is sleeved on the output end of the reduction gear set 12, and the output shaft of the micro motor 11 is inserted into the input end of the reduction gear set 12. The drive gear 10 and the arc-shaped rack 9 maintain a good meshing relationship. The dial 2 is made of transparent acrylic and has black resistance scale 5 printed on it by printing process. The dial 2 is fixed to the outer casing 1 by screws. The pointer is driven by the pointer movement (not shown in the figure) and rotates above the dial 2.

[0039] The working principle is as follows:

[0040] For example, the user needs to set the alarm value to 2.0MΩ. The user sets the 2.0MΩ alarm value via buttons on the instrument. After receiving this instruction, the unit first illuminates the white LED backlight 3. Then, based on the pre-stored scale position mapping table, it calculates that the micro motor 11 needs to rotate several steps to move the black opaque piece 8 of the annular light-transmitting sheet assembly from its current position to the 2.0MΩ mark. Subsequently, the control unit sends several pulse signals to the motor driver. After receiving the pulses, the stepper motor precisely rotates the corresponding angle, driving the entire annular light-transmitting sheet assembly to rotate a small angle through the transmission of the drive gear 10 and the arc rack 9. When the motor stops, the black opaque piece 8 at the red-green boundary is precisely aligned with the 2.0MΩ resistance mark 5 on the dial 2. At this point, the final effect seen by the user is as follows: Figure 4 As shown: White backlight shines through the ring-shaped light-transmitting sheet, displaying a bright red color in the arc-shaped area from 0 to 2.0 MΩ, and a clear green color in the area from 2.0 MΩ to the maximum range. A black opaque strip 8 clearly separates the red and green colors. This can then be used for measurement. During measurement, the pointer indicates the current measurement value against the background, allowing the user to instantly determine whether the insulation resistance is below the alarm threshold based on the pointer's background color.

[0041] Any aspects of this utility model not described in detail are well-known technologies to those skilled in the art.

[0042] The preferred embodiments of this utility model have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of this utility model without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of this utility model through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. A pointer-type insulation resistance meter, characterized in that, It includes an instrument housing, a dial mounted on the housing, a control unit located below the dial, a white LED backlight panel, and a mechanical dynamic color display system; The dial has an arc-shaped display window, and resistance scale is printed inside the arc-shaped display window; The white LED backlight panel is fixedly installed below the dial to provide uniform backlight illumination; The mechanical dynamic color display system includes an annular light-transmitting sheet assembly and a gear and rack drive mechanism for driving the annular light-transmitting sheet assembly to rotate. The annular light-transmitting sheet assembly is rotatably disposed between the white LED backlight panel and the dial. The annular light-transmitting sheet assembly is arranged inside the arc-shaped display window. The annular light-transmitting sheet assembly is formed by seamlessly splicing semi-circular red light-transmitting sheets and semi-circular green light-transmitting sheets along the diameter direction to form a complete annular sheet. The gear and rack drive mechanism is controlled by the control unit and is used to drive the annular light-transmitting sheet assembly to rotate around its center axis.

2. The pointer-type insulation resistance meter according to claim 1, characterized in that, The gear and rack drive mechanism includes an arc-shaped rack, a drive gear, and a micro motor; the arc-shaped rack is fixedly installed on the inner circumferential surface of the annular light-transmitting sheet assembly, the tooth profile of the arc-shaped rack faces the center of the circle, and the center of curvature of the arc-shaped rack coincides with the center of the annular light-transmitting sheet assembly; The micro motor is fixed inside the instrument housing; the drive gear is sleeved on the output shaft of the micro motor, and the drive gear meshes with the arc-shaped rack.

3. A pointer-type insulation resistance meter according to claim 2, characterized in that, The micro motor is either a stepper motor or a servo motor.

4. A pointer-type insulation resistance meter according to claim 1 or 2, characterized in that, It also includes a guide rail limiting structure for supporting and guiding the smooth rotation of the annular light-transmitting sheet assembly; the guide rail limiting structure includes an annular groove, the groove opening of which points to the center, the annular groove is fixed to the inner wall of the housing, and the annular light-transmitting sheet assembly is fitted into the annular groove.

5. A pointer-type insulation resistance meter according to claim 2, characterized in that, A reduction gear set is provided between the drive gear and the output shaft of the micro motor to increase torque and improve rotational accuracy.

6. A pointer-type insulation resistance meter according to claim 1, characterized in that, The red and green light-transmitting sheets are components made of colored uniform acrylic or polycarbonate material, and a black opaque sheet is embedded at the seam between the red and green light-transmitting sheets.

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