A level with constant relative error

Abstract

The application provides a horizontal instrument with constant relative error, and relates to the technical field of horizontal instrument design. The horizontal instrument with constant relative error comprises a base and a main level tube, the main level tube is arranged on the base, the main level tube is provided with a cavity for containing liquid, the top wall of the cavity is a curved surface, the projection of the curved surface on a preset plane is a preset curve, the preset plane is parallel to the length direction of the main level tube, and the equation of the preset curve is as follows: f(x) = a-a·e cx By adopting the arrangement, the horizontal instrument with constant relative error solves the problem that small range and large range can be measured, and the relative error is constant during measurement. The horizontal instrument with constant relative error can be popularized and applied to deformation monitoring of bridges, culverts and aqueducts, and inclination monitoring of geological disasters such as slopes and landslides.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of level design, in particular to a level with constant relative error. BACKGROUND

[0002] The level is a small angle measurement precision device, which is widely used in machine tool installation, high-precision test instrument leveling and other fields, and is an important measuring tool. The level is usually composed of a secondary level tube and a high-precision level tube, and the accuracy thereof is controlled by the curvature radius of the curved surface of the primary level tube. A liquid is contained in the level tube, and when the level is tilted, the air bubble in the level tube will move to the end of the level tube that is raised, so as to determine the position of the horizontal plane. The greater the curvature radius of the inner wall of the level tube, the higher the resolution, and the smaller the curvature radius, the lower the resolution. Therefore, the curvature radius of the level tube determines the accuracy of the level.

[0003] The traditional level is mainly used for detecting whether the reference of the instrument, machine tool and the like is horizontal, and the curved surface of the level tube is selected as an arc surface. In order to achieve the angle accuracy of seconds, a large curvature radius arc is selected, and the measurement range (range) is small. SUMMARY

[0004] The present application provides a level with constant relative error, wherein the primary level tube is provided with a chamber for containing liquid, the top wall of the chamber is a curved surface, the projection of the curved surface on a preset plane is a preset curve, the preset plane is parallel to the length direction of the primary level tube, and the equation of the preset curve is as follows: f(x)=a-a·e cx , which can solve the contradiction between the measurement range (range) and the error, and realize the application of the level with constant relative error in large angle measurement.

[0005] The embodiments of the present application can be implemented as follows:

[0006] In a first aspect, the present application provides a level with constant relative error, comprising:

[0007] a base;

[0008] a primary level tube provided on the base, the primary level tube being provided with a chamber for containing liquid, the top wall of the chamber being a curved surface, the projection of the curved surface on a preset plane being a preset curve, the preset plane being parallel to the length direction of the primary level tube, and the equation of the preset curve being as follows:

[0009] f(x)=a-a·e cx

[0010] wherein x is the abscissa, f(x) is the ordinate, a and c are constants, and e is the natural constant.

[0011] In an optional embodiment, the main water level pipe is connected to the base through a first threaded part, and the first threaded part is used for calibrating the main water level pipe.

[0012] In an optional embodiment, the base is provided with a through hole for the first threaded part to pass through.

[0013] In an optional embodiment, the main water level pipe is arranged along the length direction of the base.

[0014] In an optional embodiment, the relative error constant level also comprises a secondary water level pipe arranged on the base and used for selecting the direction of the inclination angle during measurement.

[0015] In an optional embodiment, the secondary water level pipe is connected to the base through a second threaded part, and the second threaded part is used for calibrating the secondary water level pipe.

[0016] In an optional embodiment, the secondary water level pipe is arranged along the width direction of the base and is perpendicular to the main water level pipe.

[0017] In an optional embodiment, the relative error constant level also comprises an upper cover arranged on the base, and the upper cover is a hollow structure and forms a space for accommodating the main water level pipe and the secondary water level pipe together with the base.

[0018] In an optional embodiment, the top of the upper cover is provided with an observation window for observing the conditions of the main water level pipe and the secondary water level pipe.

[0019] In an optional embodiment, the curved surface is provided with a scale line.

[0020] The beneficial effects of the embodiment of the present application include:

[0021] The relative error constant level comprises a base and a main water level pipe, the main water level pipe is arranged on the base, the main water level pipe is provided with a chamber for accommodating liquid, the top wall of the chamber is a curved surface, the projection of the curved surface on a preset plane is a preset curve, the preset plane is parallel to the length direction of the main water level pipe, and the equation of the preset curve is as follows: f(x)=a-a·e cx The arrangement of such a curved surface can ensure that the relative error is constant during measurement, is suitable for large-angle measurement, and solves the contradiction between the measurement range (range) and the error. BRIEF DESCRIPTION OF DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can also be obtained without creative labor on the basis of these drawings.

[0023] Figure 1Structure diagram of the level with constant relative error in the embodiment of the present application;

[0024] Figure 2 Structure diagram of the main level tube in the embodiment of the present application;

[0025] Figure 3 Sectional view of the main level tube along the preset plane in the embodiment of the present application.

[0026] Icon: 1-level with constant relative error; 10-preset plane; 11-preset curve; 20-base; 30-main level tube; 301-first connecting part; 302-second connecting part; 303-third connecting part; 304-fourth connecting part; 305-fifth connecting part; 306-top wall; 40-secondary level tube; 50-upper cover; 60-observation window; 1000-first screw; 2000-second screw. DETAILED DESCRIPTION

[0027] The level is a precision device for small angle measurement. If the measurement range (range) is to be enlarged, a smaller radius of curvature arc is selected, which greatly reduces the angle resolution of small angle measurement and greatly increases the relative error and absolute error in small angle measurement.

[0028] The present application provides a level with constant relative error, which solves the contradiction between the measurement range (range) and error, reduces the relative error in measurement, and realizes the application of the level in large angle measurement.

[0029] To make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme of the embodiments of the present application will be described clearly and completely below in combination with the drawings of the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings can be arranged and designed in various different configurations.

[0030] Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative labor are within the scope of protection of the present application.

[0031] It should be noted that: similar reference numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0032] In the description of the present application, it should be noted that if the terms "upper", "lower", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, or the orientation or positional relationship commonly used when the product of the present application is used, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0033] In addition, if the terms "first", "second" and the like appear, they are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0034] It should be noted that the features in the embodiments of the present application can be combined with each other without conflict.

[0035] Please refer to Figure 1 and Figure 2 The present embodiment provides a relative error constant level 1, which comprises a base 20 and a main level tube 30, the main level tube 30 is arranged on the base 20, the main level tube 30 is provided with a chamber for containing liquid, and the top wall 306 of the chamber is curved. In the present embodiment, the base 20 is the bearing part of the relative error constant level 1, and various components of the relative error constant level 1 are carried thereon. The main level tube 30 is arranged on the base 20, specifically, the main level tube 30 is connected to the base 20 through a first threaded part 1000, the first threaded part 1000 is used for calibrating the main level 30, the main level tube 30 is arranged along the length direction of the base 20 and in contact with the upper surface of the base 20. The base 20 is provided with a through hole for the first threaded part 1000 to pass through, and the two ends of the main level tube 30 are respectively provided with through holes for the first threaded part 1000 to pass through. When the first threaded part 1000 passes into the through hole, the relative error constant level 1 can be positioned on the plane to be measured, and the calibration of the relative error constant level 1 can be realized by adjusting the first threaded part 1000.

[0036] Figure 2 It is a structural schematic view of the main level tube 30, which comprises a first connecting part, the first connecting part comprises a first connecting part 301, a second connecting part 302, a third connecting part 303, a fourth connecting part and a fifth connecting part. The first connecting part 301 is connected to the base 20 through the first threaded part 1000, the second connecting part 302 and the third connecting part 303 are oppositely arranged on the two sides of the first connecting part 301, the fourth connecting part 304 and the fifth connecting part 305 are oppositely arranged on the two ends of the first connecting part 301, and the first connecting part 301, the second connecting part 302, the third connecting part 303, the fourth connecting part 304 and the fifth connecting part 305 together with the top wall 306 form a chamber for containing liquid.

[0037] In the embodiment, the main water level pipe 30 is surrounded by the first connecting part 301, the second connecting part 302, the third connecting part 303, the fourth connecting part 304, the fifth connecting part 305 and the top wall 306. The first connecting part 301 is in a rectangular structure. Threaded holes on the main water level pipe 30 are arranged at two ends of the first connecting part 301, which are used to position the main water level pipe 30 on the base 20 and have the function of calibrating the main water level pipe 30. The second connecting part 302 and the third connecting part 303 are oppositely arranged along the length direction of the first connecting part 301 and are both perpendicular to the first connecting part 301. The fourth connecting part 304 and the fifth connecting part 305 are oppositely arranged along the width direction of the first connecting part 301 and are both perpendicular to the first connecting part 301. The second connecting part 302, the third connecting part 303, the fourth connecting part 304 and the fifth connecting part 305 are all arranged on the upper surface of the first connecting part 301. The part, whose other end is in contact with the top wall 306, is in an arc shape, which is arranged to match the curved surface of the top wall 306 to jointly form a chamber for containing liquid.

[0038] The projection of the curved surface on the preset plane 10 is a preset curve 11. The preset plane 10 is parallel to the length direction of the main water level pipe 30. The curved surface of the chamber top wall 306 is arranged according to actual needs. In the embodiment, the equation of the preset curve 11 is as follows:

[0039] f(x)=a-a·e cx

[0040] Wherein, x is the abscissa, f(x) is the ordinate, a and c are constants, and e is the natural constant. The value of c determines the size of the relative error.

[0041] Please refer to Figure 3 In the embodiment, the preset plane 10 is Figure 3 a plane with the pattern of “x, f(x)” marked thereon, i.e. a plane extending in the x direction and the f(x) direction. The preset plane 10 is parallel to the length direction of the main water level pipe 30. The curved surface is projected on the plane to form the preset curve 11. The preset curve 11 is set as an exponential function curve, so that the relative error is constant. The specific mathematical principle is as follows:

[0042] Suppose the equation of the curved surface of the chamber top wall 306 of the main water level pipe 30 is y=f(x), x is the abscissa. Then the inclination angle at x is f′(x), and the relative error coefficient of the angle is f″(x) / f′(x). To make the relative error constant, the relative error coefficient should be a constant, i.e. it should satisfy the following equation:

[0043] f″(x)-cf′(x)=0

[0044] The solution of the equation is f(x)=a-a·e cx, so when the center of the bubble in the chamber is at x, the measured angle value is θ = |f'(x)| = ace cx The scale is marked on the corresponding x, and the current device measured inclination can be known by reading the scale of the bubble center. The product ac of the coefficients a and c determines the device resolution of the main level tube 30 at x = 0, and the coefficient c determines the size of the relative error.

[0045] It is calculated that a typical parameter of the curved surface is that a = 0.00025 and c = 0.04, so that the level 1 with a zero-point resolution of 0.01 mm / m and a constant relative error in the measurement range of 0.01 mm / m-1.2 mm / m can be realized. In other embodiments, the measurement range and the measurement relative error can be changed by adjusting the coefficients a and c.

[0046] The curved surface is set in this negative exponential function manner, which can ensure that the relative error is constant during measurement, and can perform large-angle measurement under the condition that the relative error is acceptable.

[0047] The main level tube 30 is provided with a corresponding scale according to the exponential function. Specifically, the curved surface is provided with a scale line, and the inclination value can be read through the scale line.

[0048] The level 1 with constant relative error also includes a secondary level tube 40 arranged on the base 20, which is used to select the direction of the inclination during measurement. The secondary level tube 40 is a conventional level tube, which is used to select the direction of the maximum inclination during measurement. The secondary level tube 40 includes a bottom surface and a peripheral side surface, and the bottom surface and the side surface together form a cavity for containing liquid. The liquid surface in the cavity is provided with a bubble. During actual operation, it is observed whether the bubble is in the middle position of the secondary level tube 40, and then the inclination direction during measurement is judged.

[0049] The secondary level tube 40 is connected to the base 20 through a second threaded member 2000, and the second threaded member 2000 is used to calibrate the secondary level tube 40. The bottom surface of the secondary level tube 40 is provided with a through hole for the second threaded member 2000 to pass through, and the secondary level tube 40 is calibrated through the second threaded member 2000.

[0050] The secondary level tube 40 is arranged along the width direction of the base 20 and perpendicular to the main level tube 30. The size of the secondary level tube 40 is relatively small compared with the main level tube 30. In the embodiment, the secondary level tube 40 is arranged perpendicular to the main level tube 30 and has a certain interval. The secondary level tube 40 is also provided with a limit scale line for observing the inclination direction of the level 1 with constant relative error.

[0051] The level 1 with constant relative error further comprises an upper cover 50 arranged on the base 20, the upper cover 50 is a hollow structure, and the upper cover 50 and the base 20 jointly form a space for accommodating the main level tube 30 and the auxiliary level tube 40. The upper cover 50 comprises a top plate, a first side plate, a second side plate, a third side plate and a fourth side plate, one end of the first side plate is connected with the second side plate, the end of the second side plate away from the first side plate is connected with the third side plate, the third side plate is perpendicular to the second side plate, the first side plate is perpendicular to the second side plate, the third side plate is arranged on the second side plate in the same direction as the first side plate, the end of the third side plate away from the second side plate is connected with the fourth side plate, and the other end of the fourth side plate is connected with the first side plate, the top plate is fitted with the upper edges of the first side plate, the second side plate, the third side plate and the fourth side plate respectively to form the basic structure of the upper cover 50, and the upper cover 50 is connected with the base 20 through a threaded structure to jointly form a space for placing the main level tube 30 and the auxiliary level tube 40.

[0052] The upper cover 50 is provided with an observation window 60 at the top for observing the conditions of the main level tube 30 and the auxiliary level tube 40. In the embodiment, the top plate of the upper cover 50 is provided with two observation windows 60, which are a main observation window 60 and an auxiliary observation window 60, the main observation window 60 is arranged above the main level tube 30, the auxiliary observation window 60 is arranged above the auxiliary level tube 40, the inner walls of the main observation window 60 and the auxiliary observation window 60 are arc-shaped structures, the size of the main observation window 60 is consistent with the size of the main level tube 30, and the size of the auxiliary observation window 60 is consistent with the size of the auxiliary level tube 40.

[0053] The working principle and process of the level 1 with constant relative error are as follows:

[0054] The level 1 with constant relative error is installed at a position that needs to be leveled or is used for deformation monitoring, the main level tube 30 and the auxiliary level tube 40 are fixed on the base 20 by the first threaded member 1000 and the second threaded member 2000 respectively, the upper cover 50 is covered, the positions of the bubbles in the main level tube 30 and the auxiliary level tube 40 are observed, the leveling of the level 1 with constant relative error is realized by adjusting the first threaded member 1000 and the second threaded member 2000 respectively, that is, the bubbles are in the middle positions of the main level tube 30 and the auxiliary level tube 40, and after the level 1 with constant relative error is arranged at a specified position, the deformation of structures such as bridges and aqueducts and the inclination of geological disasters such as slopes and landslides can be monitored through the observation window 60.

[0055] The level 1 with constant relative error has at least the following advantages:

[0056] The level 1 with constant relative error comprises a base 20 and a main level tube 30 arranged on the base 20, and the main level tube 30 is provided with a chamber for containing liquid, and the top wall 306 of the chamber is curved. The level 1 with constant relative error can expand the measuring range (range) by arranging the top wall 306 of the chamber of the main level tube 30 as a curved surface and arranging the corresponding curve of the curved surface as an exponential function, and the curved surface can ensure constant relative error during measurement, solve the contradiction between the measuring range (range) and the error, realize the application of the level 1 with constant relative error in large-angle measurement, and can be applied to the deformation monitoring of structures such as bridges, culverts and aqueducts and the inclination monitoring of geological disasters such as slopes and landslides.

[0057] The above is only a specific embodiment of the present application, but the protection scope of the present application is not limited thereto, any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the present application, which should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A level of constant relative error, characterized in that The utility model relates to a level gauge with constant relative error, which comprises: a base; a main level tube arranged on the base, the main level tube being provided with a cavity for containing liquid, a top wall of the cavity being a curved surface, a projection of the curved surface on a preset plane being a preset curve, the preset plane being parallel to a length direction of the main level tube, and an equation of the preset curve being as follows: wherein x is a horizontal coordinate, f (x) is a vertical coordinate, a and c are constants, and e is a natural constant; the main level tube being connected to the base through a first threaded part, the first threaded part being used for calibrating the main level tube; the main level tube being arranged along the length direction of the base.

2. A relative error constant level according to claim 1, characterized in that the base being provided with a through hole for the first threaded part to pass through.

3. The relative error constant level according to claim 1, characterized in that, The level gauge with constant relative error further comprises a secondary level tube arranged on the base and used for selecting a direction of an inclination angle during measurement.

4. A relative error constant level according to claim 3, characterized in that The secondary level tube is connected to the base through a second threaded part, and the second threaded part is used for calibrating the secondary level tube.

5. A relative error constant level according to claim 4, characterized in that The secondary level tube is arranged along a width direction of the base and is perpendicular to the main level tube.

6. The relative error constant level according to claim 3, characterized in that, The level gauge with constant relative error further comprises an upper cover arranged on the base, the upper cover being a hollow structure and forming a space for accommodating the main level tube and the secondary level tube together with the base.

7. A relative error constant level according to claim 6, characterized in that A viewing window is arranged on a top portion of the upper cover and used for observing conditions of the main level tube and the secondary level tube.

8. The relative error constant level according to claim 1, characterized in that, Scale lines are arranged on the curved surface.

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