A force vector self-calibrating multi-position weighing electronic balance and method of use thereof

Abstract

A kind of mass quantum definition electric balance and its using method belong to metrology science and quality measurement technical field.Base has worm gear lifting assembly and laser interferometer and PSD assembly, with support frame connection, and flexible hinge weighing mechanism is arranged in movable end of worm gear lifting assembly;Support frame has permanent magnet system, and the middle part of permanent magnet system has vacuum air float guide rail, and vacuum air float guide rail is matched with flexible hinge weighing mechanism, and upper and lower ends are connected with support frame, and support frame is connected by auxiliary rod, auxiliary rod is connected with induction coil, and induction coil is in the middle part of permanent magnet system, and support frame is connected with counterweight.The invention adopts vacuum air float guide rail and is connected with induction coil by rigid connection design, suppresses the horizontal displacement and rotation change of induction coil in space, reduces force vector alignment error, improves mass measurement precision, shortens work path and limits space motion posture change, realizes fast and accurate balance force zero position measurement, improves operation efficiency.

Description

Technical Field

[0001] This invention relates to a force vector self-calibrating multi-position weighing electric balance and its usage method, belonging to the field of electric balance technology. Background Technology

[0002] In the field of electric balance technology, the alignment of force vectors has always been a key technical bottleneck affecting the measurement accuracy of the device. According to the working principle of an electric balance, its core lies in controlling an energized induction coil immersed in a uniform magnetic field to balance the generated electromagnetic force vector with the weight of a standard weight. Specifically, when a 1kg standard weight is loaded onto the weighing system, it is necessary to ensure that the electromagnetic force vector generated after the induction coil is energized is perfectly aligned with the weight vector of the weight, thereby achieving mechanical balance.

[0003] However, in practice, if the induction coil is offset relative to the magnetic field space, the electromagnetic force vector generated by energization will inevitably contain a non-vertical component. This misalignment error component directly interferes with the balance of the electric balance, leading to deviations in the measurement results. More importantly, in electric balance devices employing flexible suspension systems, this non-vertical electromagnetic force component will induce yaw motion in the suspension system, resulting in dynamic changes in the relative spatial position between the induction coil and the magnetic field. This positional change further amplifies the non-vertical component of the electromagnetic force, forming a strong coupling effect of "error component - spatial attitude offset - error component amplification," significantly increasing the difficulty of force vector alignment control.

[0004] In the existing technology, research on the force vector self-alignment mechanism, alignment error suppression method and decoupling control strategy of flexible suspension system of electric balance device is still insufficient. Systematic technical breakthroughs are urgently needed to solve the above technical problems, so as to improve the balance accuracy and measurement reliability of electric balance device. Summary of the Invention

[0005] To address the problems existing in the background art, the present invention provides a force vector self-calibrating multi-position weighing electric balance and its usage method.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: a force vector self-calibrating multi-position weighing electric balance, comprising a base, a worm gear lifting assembly, a laser interferometer and PSD assembly, a flexible hinge weighing mechanism, a counterweight, an induction coil, a support frame, a vacuum air-floating guide rail, a permanent magnet system, a pulley assembly, and a bracket; the worm gear lifting assembly and multiple laser interferometers and PSD assemblies are mounted on the upper surface of the base; the worm gear lifting assembly is fixedly disposed in the middle of the base, and the flexible hinge weighing mechanism is fixedly disposed at the movable end of the worm gear lifting assembly; the multiple laser interferometers and PSD assemblies are circumferentially disposed on the outer side of the worm gear lifting assembly; the lower end of the base is fixedly connected to the support frame, and the upper end of the support frame is mounted with... A permanent magnet system is provided, in which a vertically arranged vacuum air-floating guide rail is slidably inserted in the middle. The lower end of the vacuum air-floating guide rail is configured to cooperate with a flexible hinge weighing mechanism. The upper and lower ends of the vacuum air-floating guide rail are respectively fixedly connected to the middle of the corresponding brackets. The two brackets are fixedly connected by multiple auxiliary rods. The middle of each of the multiple auxiliary rods is fixedly connected to a horizontally arranged induction coil. The induction coil is vertically slidably arranged in the middle of the permanent magnet system and is concentrically arranged with the vacuum air-floating guide rail. The outer end of the upper bracket is fixedly connected to multiple counterweights by corresponding pull ropes. Each pull rope is attached to a pulley of a corresponding pulley assembly. The pulley frame of each pulley assembly is fixedly connected to the permanent magnet system.

[0007] Furthermore, the flexible hinge weighing mechanism includes a base, a spectral confocal sensor, an upper cover, a sensor cover, and a flexible hinge; the lower end of the base is fixedly connected to the movable end of the worm gear lifting assembly, and a horizontally arranged flexible hinge is installed on the upper end of the base and clamped and fixed by the upper cover; the side of the base is connected to the working end of the horizontally arranged spectral confocal sensor and clamped and fixed by the sensor cover.

[0008] Furthermore, the flexible hinge is made of a deformable material, and the middle part of the flexible hinge is a sensing part, with multiple deformation notches evenly distributed around the circumference of the sensing part.

[0009] Furthermore, the vacuum air-bearing guide rail includes an air-bearing main shaft, an upper bushing, a lower bushing, and an outer cylinder. The lower end of the upper bushing is slidably connected to the upper end of the outer cylinder, and the upper end of the lower bushing is slidably connected to the lower end of the outer cylinder. Both the upper and lower ends of the upper and lower bushings extend to the outside of the outer cylinder and are fixedly connected to the permanent magnet system. The upper end face of the upper bushing and the lower end face of the lower bushing are provided with air inlet and exhaust ports. Both the upper and lower bushings are slidably fitted onto the outside of the air-bearing main shaft. A hemispherical pressure block is installed at the lower end of the air-bearing main shaft, and the hemispherical pressure block is configured to cooperate with the flexible hinge sensing part.

[0010] Furthermore, both the outer walls of the upper and lower bushings are provided with axial pressure equalization grooves, and each axial pressure equalization groove is connected to the corresponding air inlet and exhaust port.

[0011] Furthermore, the base is fixed to the bottom plate, the bottom plate is placed on the foundation, and leveling feet are installed between the bottom plate and the foundation.

[0012] A method for using a force vector self-calibrating multi-position weighing balance according to the present invention includes the following steps:

[0013] S1: Air is introduced into the vacuum air-bearing guide rail through the air inlet. At this time, the air-bearing main shaft presses down on the flexible hinge under the action of gravity, causing the flexible hinge to deform.

[0014] S2: Adjust the weight of the counterweight so that it pulls the air-bearing main shaft up through the bracket to the flexible hinge for balance;

[0015] S3: Place a 1kg standard weight on the upper end of the air-bearing main shaft. Due to the increased weight, the flexible hinge is compressed and deformed again.

[0016] S4: A constant DC current is passed through the coil of the permanent magnet system. The induction coil is subjected to an upward Ampere force in the magnetic field. The support drives the air-bearing main shaft to rise until the flexible hinge is balanced again, and the force balance position Z1 is obtained.

[0017] S5: Adjust the air-bearing main shaft to the designated position via the worm gear lifting assembly;

[0018] S6: Repeat S4 to obtain the force equilibrium position Z2;

[0019] S7: Repeat S5-S6 multiple times to obtain multiple force equilibrium positions.

[0020] Compared with the prior art, the beneficial effects of the present invention are:

[0021] This invention employs a vacuum-floating guide rail and, through a rigid connection design with the induction coil, suppresses the spatial horizontal displacement and rotational changes of the induction coil to within 1 μm and 1 μrad, respectively. This effectively reduces force vector alignment errors and controls the standard measurement uncertainty introduced by force vector errors to within 1 × 10⁻⁶. -8 This significantly improves the accuracy of mass measurement, shortens the work path, and limits changes in spatial motion posture, enabling rapid and accurate zero-point measurement of balance force and improving operational efficiency. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the force vector self-calibrating multi-position weighing electric balance of the present invention;

[0023] Figure 2This is a schematic diagram of the flexible hinge weighing mechanism of the present invention;

[0024] Figure 3 This is a schematic diagram of the structure of the vacuum air-bearing guide rail of the present invention;

[0025] Figure 4 This is a schematic diagram of the force balance position of the flexible hinge of the present invention;

[0026] Figure 5 This is a schematic diagram of the connection between the vacuum air-floating guide rail and the flexible hinge weighing mechanism of the present invention. Detailed Implementation

[0027] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the invention, not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0028] A force vector self-calibrating multi-position weighing electric balance includes a base 4, a worm gear lifting assembly 5, a laser interferometer and PSD assembly 6, a flexible hinge weighing mechanism 7, a counterweight 8, an induction coil 9, a support frame 10, a vacuum air-floating guide rail 11, a permanent magnet system 12, a pulley assembly 13, and a bracket 14; the PSD is a position-sensitive detector. The upper surface of the marble base 4 is equipped with a worm gear lifting assembly 5 and multiple laser interferometers and PSD assemblies 6. The worm gear lifting assembly 5 is a purchased existing technology and is fixedly installed in the middle of the base 4. A flexible hinge weighing mechanism 7 is fixed to the movable end of the worm gear lifting assembly 5. The multiple laser interferometers and PSD assemblies 6 are evenly distributed circumferentially on the outer side of the worm gear lifting assembly 5. The base 4 is fixedly connected to the lower end of the support frame 10. A permanent magnet system 12 is installed on the upper end of the support frame 10. A vertically arranged vacuum air-floating guide rail 11 is slidably inserted into the middle of the permanent magnet system 12. The lower end of the vacuum air-floating guide rail 11 is configured to cooperate with the flexible hinge weighing mechanism 7. The upper and lower ends of the vacuum air-bearing guide rail 11 are fixedly connected to the middle of the corresponding bracket 14. The two brackets 14 are fixedly connected by a plurality of auxiliary rods 25 evenly distributed along their circumference. The middle of each of the plurality of auxiliary rods 25 is fixedly connected to a horizontally arranged induction coil 9. The induction coil 9 is vertically slidably arranged in the middle of the permanent magnet system 12 and is concentrically arranged with the vacuum air-bearing guide rail 11. The outer end of the upper bracket 14 is fixedly connected to a plurality of counterweights 8 evenly distributed along their circumference by corresponding pull ropes (e.g., thin steel wires). Each pull rope is attached to the pulley of the corresponding pulley assembly 13. The pulley frame of each pulley assembly 13 is fixedly connected to the permanent magnet system 12.

[0029] Furthermore, the flexible hinge weighing mechanism 7 includes a base 16, a spectral confocal sensor 17, an upper cover 18, a sensor cover 19, and a flexible hinge 20; the lower end of the base 16 is fixedly connected to the movable end of the worm gear lifting assembly 5, and the upper end of the base 16 is equipped with a horizontally arranged flexible hinge 20, which is clamped and fixed by the upper cover 18; the side of the base 16 is connected to the working end of the horizontally arranged spectral confocal sensor 17 and is clamped and fixed by the sensor cover 19.

[0030] Furthermore, the flexible hinge 20 is preferably circular, and the material of the flexible hinge 20 is a deformable material, such as brass or beryllium bronze; the middle part of the flexible hinge 20 is a sensing part, and multiple deformation notches are evenly distributed around the circumference of the sensing part.

[0031] Based on the principle of measuring micro-strain, a flexible hinge with high dynamic characteristics, low stiffness, and no fatigue damage is designed for the flexible hinge weighing structure. The relationship between strain and force is established in the flexible hinge to achieve zero-point measurement of the equilibrium force. The measurement resolution of the flexible hinge is less than 0.5 μg, the measurement accuracy is less than 2 μg, and the repeatability is less than 1 μg.

[0032] Furthermore, the vacuum air-bearing guide rail 11 includes an air-bearing main shaft 21, an upper bushing 22, a lower bushing 23, and an outer cylinder 24; the lower end of the upper bushing 22 is slidably connected to the upper end of the inner cavity of the outer cylinder 24, and the upper end of the lower bushing 23 is slidably connected to the lower end of the inner cavity of the outer cylinder 24. The upper end of the upper bushing 22 and the lower end of the lower bushing 23 both extend to the outside of the outer cylinder 24 and are fixedly connected to the permanent magnet system 12; the upper end face of the upper bushing 22 and the lower end face of the lower bushing 23 are provided with air inlet holes and exhaust holes. The upper bushing 22 and the lower bushing 23 are slidably fitted on the outside of the air-bearing main shaft 21. A hemispherical pressure block 27 is installed at the lower end of the air-bearing main shaft 21. The hemispherical pressure block 27 is configured to cooperate with the sensing part of the flexible hinge 20.

[0033] Furthermore, both the outer wall of the upper bushing 22 and the outer wall of the lower bushing 23 are provided with circumferential axial pressure equalizing grooves 26, and each axial pressure equalizing groove 26 is connected to a corresponding air inlet and exhaust port. The axial pressure equalizing grooves 26 are used to reduce periodic gas fluctuations, thereby reducing the axial force noise of the air-bearing guide rail and suppressing the amplitude of the axial force noise of the guide device caused by air pressure flow fluctuations and suspension surface pressure fluctuations to within 1 μg.

[0034] Furthermore, the base 4 is fixed on the base plate 2, the base plate 2 is placed on the foundation 1, and a leveling foot 3 is installed between the base plate 2 and the foundation 1 to adjust the overall levelness.

[0035] A method for using a force vector self-calibrating multi-position weighing balance according to the present invention includes the following steps:

[0036] S1: Air is supplied to the vacuum air-bearing guide rail 11 through the air inlet. At this time, the air-bearing main shaft 21 presses down on the flexible hinge 20 under the action of gravity, causing the flexible hinge 20 to deform.

[0037] S2: Adjust the weight of the counterweight 8 so that the counterweight 8 pulls the air-bearing main shaft 21 up through the bracket 14 to balance the flexible hinge 20. The degree of bending of the flexible hinge 20 is obtained by the spectral confocal sensor 17.

[0038] S3: Place a 1kg standard weight 15 on the upper end of the air-bearing main shaft 21. Due to the increased weight, the flexible hinge 20 is compressed and deformed again.

[0039] S4: A constant DC current is passed through the coil of the permanent magnet system 12. The induction coil 9 is subjected to an upward Ampere force in the magnetic field. The support 14 drives the air-bearing main shaft 21 to rise until the flexible hinge 20 is balanced again, and the force balance position Z1 is obtained.

[0040] S5: Adjust the air-bearing main shaft 21 to the designated position via the worm gear lifting assembly 5;

[0041] S6: Repeat S4 to obtain the force equilibrium position Z2;

[0042] S7: Repeat S5-S6 multiple times to obtain multiple force balance positions, such as force balance position Z3, force balance position Z4 and force balance position Z5, to achieve multi-position weighing.

[0043] Throughout the experiment, the laser interferometer and PSD assembly 6 continuously measured and recorded data for experimental data evaluation.

[0044] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of the equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0045] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A force vector self-calibrating multi-position weighing balance, characterized in that: The system includes a base (4), a worm gear lifting assembly (5), a laser interferometer and PSD assembly (6), a flexible hinge weighing mechanism (7), a counterweight (8), an induction coil (9), a support frame (10), a vacuum air-floating guide rail (11), a permanent magnet system (12), a pulley assembly (13), and a bracket (14). The upper surface of the base (4) is equipped with the worm gear lifting assembly (5) and multiple laser interferometers and PSD assemblies (6). The worm gear lifting assembly (5) is fixedly located in the middle of the base (4), and the movable end of the worm gear lifting assembly (5) is fixed with a flexible hinge weighing mechanism (7). The multiple laser interferometers and PSD assemblies (6) are arranged circumferentially around the worm gear lifting assembly. On the outside of the frame (5), the base (4) is fixedly connected to the lower end of the support frame (10). A permanent magnet system (12) is installed on the upper end of the support frame (10). A vertically arranged vacuum air levitation guide rail (11) is slidably inserted into the middle of the permanent magnet system (12). The lower end of the vacuum air levitation guide rail (11) is matched with a flexible hinge weighing mechanism (7). The upper and lower ends of the vacuum air levitation guide rail (11) are fixedly connected to the middle of the corresponding bracket (14). The two brackets (14) are fixedly connected by multiple auxiliary rods (25). The middle of each of the multiple auxiliary rods (25) is fixedly connected to a horizontally arranged induction coil (9). The induction coil (9) is vertically slidably arranged in the permanent magnet system (5). The middle part of the bracket (12) is concentrically set with the vacuum air-floating guide rail (11); the outer end of the bracket (14) at the upper end is fixedly connected to multiple counterweights (8) by corresponding pull ropes, each pull rope is attached to the pulley of the corresponding pulley assembly (13), and the pulley frame of each pulley assembly (13) is fixedly connected to the permanent magnet system (12); the flexible hinge weighing mechanism (7) includes a base (16), a spectral confocal sensor (17), an upper cover (18), a sensor cover (19), and a flexible hinge (20); the lower end of the base (16) is fixedly connected to the movable end of the worm gear lifting assembly (5), and the upper end of the base (16) is equipped with a horizontally set flexible hinge (20) and The flexible hinge (20) is clamped and fixed by the top cover (18); the side of the base (16) is connected to the working end of the horizontally arranged spectral confocal sensor (17) and clamped and fixed by the sensor top cover (19); the vacuum air-bearing guide rail (11) includes an air-bearing main shaft (21), an upper bushing (22), a lower bushing (23) and an outer cylinder (24); the lower end of the upper bushing (22) is slidably connected to the upper end inside the outer cylinder (24), the upper end of the lower bushing (23) is slidably connected to the lower end inside the outer cylinder (24), and the upper end of the upper bushing (22) and the lower end of the lower bushing (23) both extend to the outside of the outer cylinder (24) and are fixedly connected to the permanent magnet system (12);The upper end face of the upper bushing (22) and the lower end face of the lower bushing (23) are provided with air inlet and exhaust holes. The upper bushing (22) and the lower bushing (23) are slidably fitted on the outside of the air-bearing main shaft (21). A hemispherical pressure block (27) is installed at the lower end of the air-bearing main shaft (21). The hemispherical pressure block (27) is configured to cooperate with the sensing part of the flexible hinge (20).

2. The force vector self-calibrating multi-position weighing balance according to claim 1, characterized in that: The flexible hinge (20) is made of a deformable material. The middle part of the flexible hinge (20) is a sensing part, and multiple deformation notches are evenly distributed around the sensing part in the circumference.

3. The force vector self-calibrating multi-position weighing balance according to claim 2, characterized in that: The outer wall of the upper bushing (22) and the outer wall of the lower bushing (23) are provided with axial pressure equalization grooves (26), and each axial pressure equalization groove (26) is connected to the corresponding air inlet and exhaust port.

4. The force vector self-calibrating multi-position weighing balance according to claim 1, characterized in that: The base (4) is fixed on the base plate (2), the base plate (2) is placed on the foundation (1), and leveling feet (3) are installed between the base plate (2) and the foundation (1).

5. A method of using a force vector self-calibrating multi-position weighing balance according to any one of claims 1-4, characterized in that: The method includes the following steps: S1: Air is supplied to the vacuum air-bearing guide rail (11) through the air inlet. At this time, the air-bearing main shaft (21) presses down on the flexible hinge (20) under the action of gravity, causing the flexible hinge (20) to deform. S2: Adjust the weight of the counterweight (8) so that the counterweight (8) pulls the air-floating main shaft (21) up through the bracket (14) to the flexible hinge (20) for balance; S3: Place a 1kg standard weight (15) on the upper end of the air-floating main shaft (21). Due to the increased weight, the flexible hinge (20) is compressed and deformed again. S4: A constant DC current is passed through the coil of the permanent magnet system (12). The induction coil (9) is subjected to an upward Ampere force in the magnetic field. The air-bearing main shaft (21) is driven to rise through the support (14) until the flexible hinge (20) is balanced again, and the force balance position Z1 is obtained.

6. The method of using the force vector self-calibrating multi-position weighing balance according to claim 5, characterized in that: The method further includes the following steps: S5: Adjust the air-bearing main shaft (21) to the specified position via the worm gear lifting assembly (5); S6: Repeat S4 to obtain the force equilibrium position Z2; S7: Repeat S5-S6 multiple times to obtain multiple force equilibrium positions.

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