CN220649843U

CN220649843U - Column type sensor

Info

Publication number: CN220649843U
Application number: CN202320817253.2U
Authority: CN
Inventors: 赵晓华; 胡文辉; 姚玉明; 柯建东
Original assignee: KELI SENSING TECHNOLOGY (NINGBO) CO LTD
Current assignee: KELI SENSING TECHNOLOGY (NINGBO) CO LTD
Priority date: 2023-04-13
Filing date: 2023-04-13
Publication date: 2024-03-22
Anticipated expiration: 2033-04-13

Abstract

The utility model relates to a column type sensor, which solves the problems that the inherent linearity of the sensor is poor, the stability of the column type sensor is not high, and the column type sensor has processing deviation, measurement deviation after loading and the like caused by the fact that the measuring range and the space limiting diameter-to-height ratio of the traditional column type sensor cannot be reduced. The column type sensor provided by the utility model comprises an elastic body and a strain gauge, wherein a constant-section column is arranged in the middle of the elastic body, a structural step is arranged between the constant-section column and the upper end and the lower end of the elastic body, and a strain gauge is arranged in a patch area on the constant-section column. When the upper end and the lower end of the elastic body are deformed by acting force, the structural steps and the column with equal cross section transmit the deformation to the strain gauge to strain, and finally the circuit outputs a voltage signal to complete the force measuring process. The utility model has the advantages of higher measurement precision, excellent stability, simple structure, convenient processing, convenient use and the like.

Description

Column type sensor

Technical Field

The utility model relates to the technical field of measuring sensors, in particular to a column type sensor.

Background

A load cell is in fact a device that converts force into a measurable electrical signal output. The actual working environment of the sensor is considered, which is important for correctly selecting the load cell, and the sensor is related to whether the sensor can work normally or not, and the safety and the service life of the sensor. The basic concept and evaluation method of the main technical indexes of the force sensor mainly comprise the differences of the quality of the new national standard and the old national standard, and mainly comprise S-shaped, cantilever-shaped, spoke-shaped, plate ring-shaped, bellows-shaped, bridge-shaped, column-shaped and the like. The column type force sensor is a functional element which converts force into electric signals by using a metal elastomer. The sensor is a force-sensitive sensor which is a mechanical-electrical integrated device and is mainly used for occasions such as electronic automobile scales, rail scales and large-scale material level monitoring by a Wheatstone bridge network formed by a resistance strain gauge stuck on an elastic sensitive surface and a certain mode thereof, and four conversion links of force, strain, resistance change and electric signal change are realized under the excitation of an external power supply.

The column type sensor has the advantages of simple structure, convenient processing and high cost performance, and is widely applied to the force measuring and weighing fields of various industries. The ratio of diameter to height is an important reference index for a column sensor, the smaller the diameter to height ratio, the better the intrinsic linearity of the column sensor. To reduce this index, designers typically either reduce the diameter of the pillar sensor or increase the height of the pillar sensor. However, in some occasions with limited mounting heights, the height is unchanged, and the diameter cannot be reduced due to the limitation of the measuring range; or a column type sensor with a larger measuring range, the diameter is larger, and the height of the sensor cannot be increased infinitely. Therefore, the research on solving the aspect ratio problem of the column type sensor is significant.

Disclosure of Invention

The utility model aims to solve the problems that the diameter-to-height ratio of a column type sensor cannot be reduced due to the limitation of a measuring range and a space, the inherent linearity is poor, the stability of the column type sensor is not high, the column type sensor has machining deviation, measuring deviation after loading and the like, and provides the column type sensor which has the advantages of higher measuring precision, excellent stability, simple structure, convenience in machining and convenience in use.

The technical problems are solved by the following technical scheme: the column type sensor comprises an elastic body and a strain gauge, wherein a plurality of constant-section columns are arranged in the middle of the elastic body, and strain gauges are arranged in the middle of the constant-section columns. The upper end and the lower end of the elastic body can be used as force measuring ends, when external force acts on the upper end and the lower end of the elastic body, the upper end and the lower end of the elastic body are correspondingly deformed, the strain gauge is transmitted to the constant cross section column arranged in the middle of the elastic body, the strain gauge is connected with a circuit, corresponding voltage signals are output, and the force measuring process is completed. The column type sensor converts the force into the deformation of the elastic body, and then the strain gauge of the connecting circuit converts the force into a required electric signal, so that the column type sensor is simple in structure and high in efficiency and convenience in use.

Preferably, the section of the isosceles right triangle column is a combination of a rectangle and an isosceles right triangle, and the bottom side of the isosceles right triangle coincides with one side of the rectangle. For a traditional single column sensor, the smaller the diameter-to-height ratio, the better the intrinsic linearity of the column sensor, and the higher the measurement accuracy. Therefore, in practical situations, the diameter of the column type sensor is often reduced or the height of the column type sensor is pulled up to reduce the diameter of the column type sensor, but due to the limitation of the measuring range, the diameter of the column type sensor cannot be reduced infinitely, the practical space is limited, and the height of the column type sensor has a corresponding upper limit, so that the diameter-to-height ratio of the column type sensor can be reduced to a certain extent only. The utility model indirectly reduces the diameter of the column type sensor, reduces the diameter-to-height ratio and improves the linearity by arranging the column with the equal cross section in the middle of the elastic body, solves the problem of poor inherent linearity caused by the fact that the diameter-to-height ratio of the column type sensor cannot be reduced due to the limitation of measuring range and space, and improves the measuring precision of the sensor. The cross section of the isosceles right triangle and the rectangular isosceles right triangle can ensure that the isosceles right triangle and the rectangular isosceles right triangle are heated uniformly when being subjected to heat treatment on the periphery of the isosceles right triangle, so that the processing and forming of the column type sensor are facilitated, the heat treatment hardness of the sensor is improved, the inherent linearity of the sensor is improved, and the measurement accuracy is improved. The inner side section of the column with the constant section is arranged to be an isosceles right triangle, so that the column type sensor keeps balanced stress during force measurement, and the stability is improved.

Preferably, structural steps are arranged between the upper end and the lower end of the elastic body and the constant cross-section posts, the constant cross-section posts are distributed around the middle of the elastic body, the isosceles right triangle sides of the constant cross-section posts are positioned on the inner side of the middle of the elastic body, the outer side faces of the rectangular sides of the constant cross-section posts are cambered surfaces, and the outer side faces of the rectangular sides and the outer peripheral faces of the structural steps are on the same peripheral face. After the elastic body is elastically deformed, the structural steps and the constant cross-section columns distributed around the middle of the elastic body transfer deformation to the strain gauge. When the stress at the upper end or the lower end of the elastic body is uneven, because the external force is concentrated on one side of the circumference of the elastic body, if the outer side surface of the rectangular side of the column with the same cross section is not on the same circumference surface with the outer circumference surface of the structural step, the whole sensor is unbalanced and biased to one side with larger stress, the whole structure of the sensor is easily unstable, and the accuracy of the force measurement result is influenced. The outer side surface of the rectangular side of the constant-section column and the outer circumferential surface of the structural step are kept on the same circumferential surface, so that the problem of low stability of the column type sensor is effectively solved.

Preferably, the number of the equal cross-section posts is four, the right-angle sides of the four equal cross-section posts are correspondingly parallel, and the equal cross-section posts are distributed at equal intervals in the middle of the elastomer. The number of the equal-section posts is four, and a foundation is provided for the subsequent construction of a Wheatstone bridge for outputting electric signals for strain gauges arranged on the equal-section posts. The right-angle edges of the four equal-section columns are kept parallel, contact balance between the structural steps and the equal-section columns is kept in the loading and force measuring process of the sensor, the overall stability of the sensor is improved, meanwhile, the equal-section columns are distributed at equal intervals, on one hand, enough supporting force is provided for the force measurement of the sensor, the stability is enhanced, and on the other hand, great convenience is provided for the processing and manufacturing of the column type sensor.

Preferably, the structural step is a cylinder, the diameter of the structural step is smaller than the diameter of the upper end and the lower end of the elastic body, and the height of the structural step is smaller than the height of the upper end and the lower end of the elastic body. When external force acts on two ends of the elastic body, if the upper end and the lower end of the elastic body are directly contacted with the column with the same cross section, the pressure generated under the same pressure condition is larger due to small contact area, so that the stability of the sensor is not facilitated, the structural step can be used as a transition part for deformation transmission of the elastic body, the safety and stability of the sensor in the force measuring process are improved, the radius of the structural step with smaller height is smaller, and the reduction of the diameter-height ratio of the whole column type sensor is also contributed.

Preferably, the upper and lower ends of the elastic body are cylinders, and the upper and lower ends of the elastic body, the structural steps and the column with the equal cross section are integrally formed. The upper end, the lower end, the structural steps and the column with equal cross section of the elastic body are integrally formed, so that for a traditional single-column sensor with the same diameter-to-height ratio, the height of the sensor is reduced, the diameter-to-height ratio of the sensor is effectively reduced, the inherent linearity is improved, the integral gravity center of the sensor is reduced, and the stability of the sensor is enhanced.

Preferably, the middle part of the constant cross section column is provided with a patch area, the patch areas are symmetrically arranged on the planes at two sides of the constant cross section column, and strain gauges are arranged on the patch areas. Compared with the patch area of the traditional single-column sensor, the molding of the constant-section column effectively reduces the cross section area of the patch area, and the quenching hardness of the patch area can more easily meet the minimum requirement of azimuth error and can more easily meet the optimal requirement of sensor performance. And strain gauges are laid on the mutually parallel patch cylindrical surfaces, and the stress deformation of the elastic body is transferred to the strain gauges.

Preferably, the strain gauges on the column with the equal cross section are provided with a transverse strain gauge and a vertical strain gauge, and the transverse strain gauge and the vertical strain gauge are rectangular. The constant-section column transmits the stress deformation of the elastic body to the strain gauge of the patch area, and the transverse strain gauge and the vertical strain gauge strain output signals. The transverse strain gauge and the vertical strain gauge adopt a rectangular sheet forming mode, so that the strain sensitivity of the strain gauge can be improved better, and the measurement accuracy level of the column type sensor is improved.

Preferably, both ends of the transverse strain gauge and the vertical strain gauge on the strain gauge are provided with cable interfaces. And the transverse strain gauge and the vertical strain gauge on the strain gauge are connected and built with a Wheatstone bridge through a cable interface, and the cable is gathered into one path of signal output to finish the force measuring process. The Wheatstone bridge formed by constructing the transverse strain gauge and the vertical strain gauge of the column type sensor can compensate the deviation caused by the factors such as the processing deviation of the elastic body, the deviation from a measuring shaft after loading and the like, and the linearity error of the sensor is reduced. The force measuring precision and the long-term stability of the column type sensor are greatly improved, and meanwhile, the cost is low.

The beneficial effects of the utility model are as follows: the utility model has simple structure and convenient processing, and can reduce the diameter-to-height ratio of the column type sensor, improve the inherent linearity of the column type sensor and ensure certain measurement accuracy due to the molding of a plurality of columns with equal cross sections; on the other hand, the uniformity of the heat treatment temperature around the column with the constant cross section can be ensured, and the heat treatment hardness is improved, so that the stability of the column type sensor is improved. Meanwhile, the Wheatstone bridge is built through the strain gauge on the column type sensor, so that the deviation caused by the factors such as the processing deviation of the elastic body, the deviation from the measuring shaft after loading and the like can be compensated.

Drawings

Fig. 1 is a structural diagram of the present utility model.

Fig. 2 is a block diagram of a strain gage on a patch area of the present utility model.

Fig. 3 is a middle horizontal cross-sectional view of the present utility model.

Fig. 4 is a circuit diagram of the connection of the wheatstone bridge in the first embodiment of the present utility model.

In the figure: 1. a strain gauge I; 1.1, a transverse strain gauge of a strain gauge I; 1.2, a vertical strain gauge of a strain gauge I; 2. a strain gauge II; 2.1, a transverse strain gauge of the strain gauge II; 2.2, a vertical strain gauge of the strain gauge II; 3. strain gage III; 3.1, a transverse strain gauge of a strain gauge III; 3.2, a vertical strain gauge of the strain gauge III; 4. strain gauge IV; 4.1, a transverse strain gauge of a strain gauge IV; 4.2, a vertical strain gauge of the strain gauge IV; 5. strain gauges V; 5.1, a transverse strain gauge of a strain gauge V; 5.2, a vertical strain gauge of a strain gauge V; 6. strain gauges; 6.1, a transverse strain gauge of the strain gauge; 6.2, a vertical strain gauge of the strain gauge; 7. strain gage seven; 7.1, a transverse strain gauge of strain gauge seven; 7.2, a vertical strain gauge of strain gauge seven; 8. strain gauges eight; 8.1, a transverse strain gauge of the strain gauge eight; 8.2, a vertical strain gauge of the strain gauge eight; 9. an elastomer; 10. a structural step; 11. a column with equal cross section; 12. a patch area; 13. and a cable interface.

Detailed Description

Specific embodiments of the utility model will be described in detail below, it being noted that the embodiments described herein are for illustration only and are not intended to limit the utility model. In the following description, numerous specific details are provided for specific embodiments of the utility model. It will be apparent, however, to one skilled in the art that these specific details need not be employed to practice the present utility model.

Embodiment one: as shown in fig. 1, the utility model consists of an elastic body 9 and a strain gauge 6, wherein the upper end and the lower end of the elastic body 9 are both cylinders, and any one end can be used as a force measuring end. While the conventional column sensor is generally of a single column structure, the elastic body 9 of the present utility model is provided with a plurality of columns 11 having equal cross-section in the middle thereof, and a structural step 10 is provided between the columns 11 having equal cross-section and the upper and lower ends of the elastic body 9. The structural step 10 is a cylinder, and is relatively flat relative to the upper and lower ends of the elastic body 9, the diameter and the height of the structural step 10 are smaller than those of the upper and lower ends of the elastic body 9, and the structural step 10, the upper and lower ends of the elastic body 9 and the constant section column 11 are integrally formed and made of elastic materials. As shown in fig. 3, the cross section of the isosceles right triangle column 11 is a combination of an isosceles right triangle and a rectangle, and the bottom side of the isosceles right triangle coincides with one side of the rectangle. The number of the equal cross section posts 11 is four, the right-angle sides of the four equal cross section posts 11 are correspondingly parallel, the equal cross section posts 11 are distributed around the middle of the elastic body 9 at equal intervals, one side of the equal cross section post 11 with the isosceles right triangle shape faces the inside of the integral column type sensor, one side of the equal cross section post 11 with the rectangular shape is a cambered surface, the equal cross section post is kept on the same circumferential surface with the outer circumferential surface of the structural step 10, and the upper end and the lower end of the equal cross section post 11 are in contact with the structural step 10, so that the two ends of the elastic body 9 are stably supported. The patch area 12 is laid in the middle of the column 11, the patch area 12 is symmetrically arranged on the planes at two sides of the column 11, the strain gauge 6 is laid on the patch area 12, and eight strain gauges on the four columns 11 are respectively 1, 2, 3, 4, 5, 6, 7 and 8. Fig. 2 shows a strain gauge 6 attached to the patch area 12, and when the strain gauge 6 is disposed on the patch area 12, a suitable adhesive is selected according to the type of the strain gauge 6, and is cured by heating. The strain gauge 6 integrates the transverse strain gauge 6.1 and the vertical strain gauge 6.2, the strain gauge is rectangular and lamellar, lighter materials are selected, and the strain sensitivity is kept in a proper range so as to ensure the measurement accuracy of the sensor. The strain gauge 6 is provided with a cable interface 13, the strain gauge is connected with a Wheatstone bridge shown in fig. 4 through a cable, deformation of the elastic body 9 caused by stress is transmitted through the structural step 10 and the column 11 with the equal cross section, the strain gauge 6 is strained, and finally the strain gauge is converted into an electric signal to be converged into one path for output, and the force measuring process is completed. As shown in fig. 4, the transverse strain gauge 6.1 and the vertical strain gauge 6.2 on the same side of the column 11 with equal cross sections are respectively arranged in the same bridge arm, the strain gauges on the same bridge arm are connected in series and then connected in parallel, namely, the first bridge arm is formed by connecting the vertical strain gauge 2.2 of the strain gauge second and the vertical strain gauge 6.2 of the strain gauge sixth in series, the vertical strain gauge 3.2 of the strain gauge third and the vertical strain gauge 7.2 of the strain gauge seventh in series, then the two series circuits are connected in parallel, the second bridge arm is formed by connecting the transverse strain gauge 2.1 of the strain gauge second and the transverse strain gauge 6.1 of the strain gauge sixth in series, the transverse strain gauge 3.1 of the strain gauge third and the transverse strain gauge 7.1 are connected in parallel, the third bridge arm is formed by connecting the vertical strain gauge 1.2 of the strain gauge first and the vertical strain gauge 5.2 of the strain gauge fifth in series, the vertical strain gauge 4.2 of the strain gauge and the strain gauge eighth in series, and then the four strain gauge 8.2 of the strain gauge and the strain gauge fourth bridge arm are formed by connecting the transverse strain gauge 1.1 and the strain gauge 1.1 in series and the transverse strain gauge 1. In the wheatstone circuit constructed in fig. 4, the common ends of the first bridge arm and the second bridge arm of the wheatstone circuit are connected with the power supply excitation positive end, the common ends of the third bridge arm and the fourth bridge arm are connected with the power supply excitation negative end, the common ends of the first bridge arm and the fourth bridge arm are connected with the signal output positive end, and the common ends of the second bridge arm and the third bridge arm are connected with the signal output negative end.

Claims

1. The column type sensor comprises an elastic body (9) and a strain gauge (6), and is characterized in that a plurality of equilateral cross-section columns (11) are arranged in the middle of the elastic body (9), strain gauges are arranged in the middle of the equilateral cross-section columns (11), the cross section of the equilateral cross-section columns (11) is a combination of a rectangle and an isosceles right triangle, and the bottom edge of the isosceles right triangle coincides with one edge of the rectangle.

2. The column type sensor according to claim 1, wherein a structural step (10) is arranged between the upper end and the lower end of the elastic body (9) and an equilateral cross-section column (11), the equilateral cross-section column (11) is distributed around the middle of the elastic body (9), the isosceles right triangle side of the equilateral cross-section column (11) is located at the inner side of the middle of the elastic body (9), the outer side face of the rectangular side of the equilateral cross-section column (11) is an arc face, and the outer side face of the rectangular side and the outer peripheral face of the structural step (10) are on the same peripheral face.

3. The column sensor according to claim 1, wherein the number of the equal cross-section columns (11) is four, right-angle sides of the four equal cross-section columns (11) are correspondingly parallel, and the equal cross-section columns (11) are distributed at equal intervals in the middle of the elastic body (9).

4. A column sensor according to claim 2, characterized in that the structural step (10) is a cylinder, the diameter of the structural step (10) is smaller than the diameter of the upper and lower ends of the elastic body (9), and the height of the structural step (10) is smaller than the height of the upper and lower ends of the elastic body (9).

5. A column sensor according to claim 2, wherein the upper and lower ends of the elastic body (9) are cylindrical, and the upper and lower ends of the elastic body (9), the structural step (10) and the constant cross-section column (11) are integrally formed.

6. The column type sensor according to claim 1, wherein a patch area (12) is arranged in the middle of the column (11), the patch area (12) is symmetrically arranged on the planes at two sides of the column (11), and the strain gauge (6) is arranged on the patch area (12).

7. A column sensor according to claim 5, characterized in that the strain gauges (6) on the column (11) are provided with transverse strain gauges (6.1) and vertical strain gauges (6.2), the transverse strain gauges (6.1) and vertical strain gauges (6.2) each being rectangular.

8. Column sensor according to claim 6, characterized in that both ends of the transverse strain gauge (6.1) and the vertical strain gauge (6.2) on the strain gauge (6) are provided with cable interfaces (13).