CN117629359A - Weighing sensor and weighing device - Google Patents

Abstract

The invention belongs to the technical field of sensors, and particularly relates to a weighing sensor and a weighing device. The weighing sensor comprises a sensing main body, and a first cantilever and a second cantilever which are respectively connected to two opposite sides of the sensing main body; the first cantilever, the second cantilever and the sensing main body are arranged in parallel; the first cantilever is connected to the first end of the sensing main body and extends towards the second end; the second cantilever is connected to the second end of the sensing main body and extends towards the first end; a first space is formed between the first cantilever and the sensing main body, and a second space is formed between the second cantilever and the sensing main body; the height of the first space is equal to the height of the second space; the sensing main body is provided with a through hole; the weighing sensor also comprises a strain assembly attached to the sensing main body at a position corresponding to the through hole. The invention can ensure the stable and reliable weighing result and high precision of the weighing result.

Description

Weighing sensor and weighing device

Technical Field

The invention belongs to the technical field of sensors, and particularly relates to a weighing sensor and a weighing device.

Background

Currently, in cell handling equipment, the fluid bag is weighed using mainly cantilever or S-type load cells. However, the cantilever type weighing sensor in the prior art has poor stability and reliability; the angle difference of the S-shaped weighing sensor is large, and the precision is low; for cell handling equipment with high precision and high reliability weighing requirements during cell handling, none of the weighing sensors described in the prior art clearly meet their weighing requirements.

Disclosure of Invention

The invention provides a weighing sensor and a weighing device, aiming at the technical problems of low precision, poor reliability and the like of the weighing sensor in the prior art.

In view of the above technical problems, an embodiment of the present invention provides a weighing sensor, including a sensing main body, and a first cantilever and a second cantilever respectively connected to opposite sides of the sensing main body; the first cantilever, the second cantilever and the sensing main body are arranged in parallel; the first cantilever is connected to the first end of the sensing main body and extends towards the second end; the second cantilever is connected to the second end of the sensing main body and extends towards the first end; a first space is formed between the first cantilever and the sensing main body, and a second space is formed between the second cantilever and the sensing main body; the height of the first space is equal to the height of the second space; the sensing main body is provided with a through hole; the weighing sensor further comprises a strain assembly attached to the sensing main body at a position corresponding to the through hole.

Optionally, on a preset reference plane, the height of the first space is greater than the body height of the sensing body; the preset reference surface is a surface perpendicular to the first surface and parallel to the extending direction of the first cantilever; the first surface is a surface of the sensing main body opposite to the first cantilever, and is positioned on the inner side wall of the first space;

the strain assembly comprises at least two first strain pieces, wherein the at least two first strain pieces are attached to the first surface or/and the second surface at intervals and are opposite to the through holes; the second surface is a surface of the sensing body opposite to the second cantilever, and the second surface is located on the inner side wall of the second space.

Optionally, the through hole comprises a first arc hole, a connecting hole and a second arc hole which are sequentially communicated along the extending direction of the first cantilever; at least two first strain gauges are respectively attached to the first surface or/and the second surface at positions opposite to the first arc-shaped holes and the second arc-shaped holes.

Optionally, on a plane parallel to the preset reference plane, the sections of the first arc-shaped hole and the second arc-shaped hole are all circular, and the center points of at least two first strain gauges are aligned with the circle centers of the circular first arc-shaped hole and the circular second arc-shaped hole respectively.

Optionally, the connecting hole comprises a first transition hole communicated with the first arc-shaped hole, a second transition hole communicated with the second arc-shaped hole and a step hole communicated between the first transition hole and the second transition hole; on the plane parallel to the preset reference plane, the first transition hole and the second transition hole are arranged in parallel, the step hole and the first transition hole are arranged vertically, and the width of the step hole is smaller than or equal to the width of the first preset gap.

Optionally, on the plane parallel to the preset reference plane, the cross section of the connecting hole is rectangular, the first arc hole and the second arc hole are symmetrically arranged on two opposite sides of the connecting hole, and the highest height of the circular first arc hole is greater than the height of the rectangular connecting hole.

Optionally, on a plane parallel to the preset reference plane, the height of the first cantilever is equal to the height of the second cantilever, and the height of the first cantilever is greater than the height of the sensing main body.

Optionally, on a preset reference plane, the height of the first space is smaller than or equal to the body height of the sensing body; the preset reference surface is a surface perpendicular to the first surface and parallel to the extending direction of the first cantilever; the first surface is a surface of the sensing main body opposite to the first cantilever, and is positioned on the inner side wall of the first space;

the strain assembly comprises at least two second strain pieces, wherein the at least two second strain pieces are attached to a third surface or/and a fourth surface of the inner side wall of the through hole at intervals, the fourth surface is opposite to the third surface and is arranged in parallel, and the third surface is parallel to the first surface.

Optionally, on a plane parallel to the preset reference plane, the cross section of the through hole is rectangular, the height of the first cantilever is equal to the height of the second cantilever, and the height of the through hole is greater than the height of the first space and the height of the first cantilever.

Optionally, a first limiting part is arranged at the second end of the first cantilever, a second limiting part is arranged at the second end of the sensing main body, the first limiting part and the second limiting part are oppositely arranged, and a first limiting gap is formed between the first limiting part and the second limiting part; the first end of the second cantilever is provided with a third limiting part, the first end of the sensing main body is provided with a fourth limiting part, the third limiting part and the fourth limiting part are arranged oppositely, and a second limiting gap is formed between the third limiting part and the fourth limiting part; the width of the first limiting gap is equal to that of the second limiting gap, and the width of the first limiting gap is smaller than that of the second preset gap.

Optionally, the load cell further comprises a protective housing mounted on the sensor body and completely covering the through hole and at least partially covering the first space and the second space.

The embodiment of the invention also provides a weighing device which comprises the weighing sensor.

The weighing sensor comprises a sensing main body, a first cantilever and a second cantilever which are respectively connected to two opposite sides of the sensing main body; the first cantilever, the second cantilever and the sensing main body are arranged in parallel; the first cantilever is connected to the first end of the sensing main body and extends towards the second end; the second cantilever is connected to the second end of the sensing main body and extends towards the first end; a first space is formed between the first cantilever and the sensing main body, and a second space is formed between the second cantilever and the sensing main body; the height of the first space is equal to the height of the second space; the sensing main body is provided with a through hole; the weighing sensor further comprises a strain assembly attached to the sensing main body at a position corresponding to the through hole. According to the weighing sensor, when the first cantilever or/and the second cantilever is/are subjected to the pulling pressure, the deformation generated on the sensing main body can be measured through the strain component arranged on the sensing main body, so that the weighing result corresponding to the pulling pressure is determined.

Drawings

The invention will be further described with reference to the drawings and examples.

Fig. 1 is a schematic perspective view of a load cell according to an embodiment of the present invention.

Fig. 2 is a front view of a load cell provided in an embodiment of the invention.

Fig. 3 is a right side view of a load cell provided in an embodiment of the invention.

Fig. 4 is a schematic view of the structure of a section A-A of the load cell according to the first embodiment of the invention.

Fig. 5 is a schematic view of the structure of a section A-A of a load cell according to a second embodiment of the invention.

FIG. 6 is a schematic view of the structure of a section A-A of a load cell according to a third embodiment of the invention.

FIG. 7 is a schematic view of the structure of a section A-A of a load cell according to a fourth embodiment of the invention.

Fig. 8 is a schematic structural view of a section parallel to a preset reference plane of a load cell according to an embodiment of the present invention.

Reference numerals in the specification are as follows:

1. a sensing body; 11. a first end; 12. a second end; 13. a through hole; 131. a first arcuate aperture; 132. a connection hole; 1321. a first transition aperture; 1322. a step hole; 1323. a second transition aperture; 133. a second arcuate aperture; 14. a first surface; 15. a second surface; 16. a third surface; 17. a fourth surface; 18. a second limit part; 19. a fourth limit part; 2. a first cantilever; 21. a first limit part; 22. a first limit slit; 3. a second cantilever; 31. a third limit part; 32. a second limit slit; 4. a first space; 5. a second space; 6. a strain assembly; 61. a first strain gage; 62. a second strain gage; 7. a mounting hole; 8. and a protective shell.

Detailed Description

In order to make the technical problems, technical schemes and beneficial effects solved by the invention more clear, the invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention.

It is to be understood that the directions or positional relationships indicated by the terms "upper", "lower", "left", "right", "front", "rear", "middle", etc., are based on the directions or positional relationships shown in the drawings, are merely for convenience of description and simplification of the description, and do not indicate or imply that the apparatus or element in question must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as limiting the invention.

As shown in fig. 1 to 8, an embodiment of the present invention provides a weighing sensor including a sensing body 1, and first and second cantilevers 2 and 3 respectively connected to opposite sides of the sensing body 1; the first cantilever 2, the second cantilever 3 and the sensing main body 1 are arranged in parallel; the first cantilever 2 is connected to the first end 11 of the sensing body 1 and extends towards the second end 12 (in the present invention, the first end and the second end may refer to the first end and the second end of the entire weighing sensor, and may refer to the first end 11 and the second end 12 of the sensing body 1, the first cantilever 2 or the second cantilever 3, respectively); the second cantilever 3 is connected to the second end 12 of the sensing body 1 and extends towards the first end 11; a first space 4 is defined between the first cantilever 2 and the sensing main body 1, and a second space 5 is defined between the second cantilever 3 and the sensing main body 1; the height of the first space 4 is equal to the height of the second space 5; the sensing main body 1 is provided with a through hole 13; the load cell further comprises a strain assembly 6 attached to the sensing main body 1 at a position corresponding to the through hole 13, and the strain assembly 6 comprises a plurality of strain gauges, such as 2, 4, 8, etc. It will be appreciated that in the present invention, the lengths of the first cantilever 2, the second cantilever 3 and the sensing body 1 are all equal in the extension direction in which the first cantilever 2 extends from the first end 11 to the second end 12. The first cantilever 2 with the hookup location of sensing main part 1, the inside wall in first space 4 sets up to the transition cambered surface, and is the same as the same, the second cantilever 3 with the hookup location of sensing main part 1, the inside wall in second space 5 sets up to the transition cambered surface, so, can reduce the stress concentration in this position, promotes its reliability and stability.

According to the weighing sensor disclosed by the invention, when the first cantilever 2 or/and the second cantilever 3 is subjected to the pulling pressure, the deformation generated on the sensing main body 1 can be measured through the strain component 6 arranged on the sensing main body 1, so that the weighing result corresponding to the pulling pressure is determined.

In an embodiment, as shown in fig. 1 to 2 and fig. 4 to 8, the second end 12 of the first cantilever 2 is provided with a first limiting portion 21, the second end 12 of the sensing body 1 is provided with a second limiting portion 18, the first limiting portion 21 is opposite to the second limiting portion 18, and a first limiting gap 22 is formed between the first limiting portion 21 and the second limiting portion 18; as shown in fig. 4, the second end 12 of the sensing main body 1 protrudes towards the second end 12 of the first cantilever 2, and a first clamping groove matched with the first clamping hook is formed on the second end 12 of the first cantilever 2 in a concave manner, in turn, the first clamping hook is installed in the first clamping groove, a first limit gap 22 is formed between the outer side wall of the first clamping hook and the inner side wall of the first clamping groove, and when the first cantilever 2 or the second cantilever 3 is subjected to tensile pressure and deformed, at least one section of the first limit gap 22 in the structure shown in fig. 4 is gradually reduced; for example, if in the first limiting slit 22 shown in fig. 4, a slit section corresponding to the gap between the top surface of the first hook and the first clamping groove in the first limiting slit 22 is smaller under the action of the pulling pressure (similarly, when the slit section is larger, other sections of the first limiting slit 22 are smaller, and the effect of preventing overload is also achieved), when the pulling pressure reaches a certain limit value, the top surface of the first hook abuts against the first clamping groove, and at this time, even if the pulling pressure continuously increases, the deformation of the first cantilever 2 is not changed greatly, so that the torque bending moment deformation of the weighing sensor is not caused due to overload; thus, overload of the weighing sensor can be prevented, and reliability of weighing results is improved.

The first end 11 of the second cantilever 3 is provided with a third limiting part 31, the first end 11 of the sensing main body 1 is provided with a fourth limiting part 19, the third limiting part 31 and the fourth limiting part 19 are arranged opposite to each other, and a second limiting gap 32 is formed between the third limiting part 31 and the fourth limiting part 19; as shown in fig. 4, the first end 11 of the sensing main body 1 protrudes towards the first end 11 of the first cantilever, and a second clamping groove matched with the second clamping hook is formed on the first end 11 of the second cantilever 3 in a concave manner, in turn, the second clamping hook is installed in the second clamping groove, a second limiting gap 32 is formed between the outer side wall of the second clamping hook and the inner side wall of the second clamping groove, and when the second cantilever 3 or the first cantilever 2 is subjected to tensile pressure and deformed, at least one section of the second limiting gap 32 in the structure shown in fig. 4 is gradually reduced; for example, if in the second limiting slit 32 shown in fig. 4, a slit section corresponding to the second clamping groove between the bottom surface of the second cantilever 3 and the second hook is smaller under the action of the pulling pressure (similarly, when the slit section is larger, other sections of the second limiting slit 32 are smaller, and the overload prevention function is also achieved), when the pulling pressure reaches a certain limit value, the bottom surface of the second clamping groove abuts against the second hook, and at this time, even if the pulling pressure is continuously increased, the deformation of the second cantilever 3 is not changed greatly, so that the torque bending moment deformation of the weighing sensor is not caused due to the overload; thus, overload of the weighing sensor can be prevented, and reliability of weighing results is improved.

The width of the first limiting gap 22 is equal to that of the second limiting gap 32, and the width of the first limiting gap 22 is smaller than that of the second preset gap, that is, in order to ensure that the stress at two ends of the weighing sensor is balanced, the weighing sensor is convenient to measure, so that the width of the first limiting gap 22 is equal to that of the second limiting gap 32. In this embodiment, the second preset gap width is used to characterize the magnitude of the overload pulling pressure that can be correspondingly borne when the load cell is overloaded (when the overload pulling pressure is borne and overload occurs, the first limit gap 22 or the second limit gap 32 may be reduced to zero by the second preset gap width), so that the widths of the first limit gap 22 and the second limit gap 32 are set to be smaller than the second preset gap width, and at least one of the first limit gap 22 and the second limit gap 32 may be reduced to zero before the load cell is subjected to the overload pulling pressure, so that overload of the load cell can be prevented, and reliability of the weighing result can be improved.

Further, as shown in fig. 1, the load cell further comprises a protective shell 8 mounted on the sensor body and completely covering the through hole 13 and at least partially covering the first space 4 and the second space 5. The shape of the protective housing 8 may be set according to the requirement, the protective housing 8 needs to completely cover the through hole 13 to protect the through hole 13 and components mounted in the through hole 13, and the protective housing 8 needs to cover at least a part (i.e. may completely or partially cover) of the first space 4 and the second space 5 to protect components mounted in the first space 4 and the second space 5.

In an embodiment, as shown in fig. 4 to 7, on a preset reference plane, the height of the first space 4 is greater than the body height of the sensing body 1; the preset reference plane is a plane perpendicular to the first surface 14 and parallel to the extending direction of the first cantilever 2; the first surface 14 is a surface of the sensing body 1 opposite to the first cantilever 2, and the first surface 14 is located on an inner side wall of the first space 4; in this embodiment, when the height of the first space 4 is greater than the body height of the sensing body 1, the height of the second space 5 coincides with the height of the first space 4, and thus, the height of the second space 5 is also greater than the body height of the sensing body 1. The strain assembly 6 comprises at least two first strain sheets 61, and the at least two first strain sheets 61 are attached to the first surface 14 or/and the second surface 15 at a position opposite to the through hole 13 at intervals; the second surface 15 is a surface of the sensing body 1 opposite to the second cantilever 3, and the second surface 15 is located on an inner sidewall of the second space 5. In this embodiment, when the heights of the first space 4 and the second space 5 are both greater than the main body height of the sensing main body 1, the first strain gauge 61 may be attached to the first surface 14 or the second surface 15, or one half of the first strain gauge is attached to the first surface 14, and the other half of the first strain gauge is attached to the second surface 15 symmetrically, specifically, as shown in fig. 4 and 6, two first strain gauges 61 are provided on each of the first surface 14 and the second surface 15, and the strain assembly 6 includes four first strain gauges 61 in total; however, in the embodiment shown in fig. 5 and 7, the first surface 14 is provided with two first strain gages 61, and the second surface 15 is not provided with strain gages, and the strain assembly 6 includes two first strain gages 61 in total; in the present invention, the strain assembly 6 is not limited to include only two or four first strain gages 61, but may include eight or other numbers of first strain gages 61. In this embodiment, as shown in fig. 4 to 7, since the height of the sensing body 1 is small (thinner) with respect to the first space 4 and the second space 5, the tensile force applied to the first cantilever 2 and the second cantilever 3 can be better and faster transferred to the sensing body 1 to deform the sensing body, so that the deformation of the sensing body 1 can be directly measured by attaching the first strain gauge 61 to the first surface 14 or/and the second surface 15, and the accuracy of the finally measured weighing result can be ensured by the above-mentioned directly measured deformation (compared with the scheme that the sensing piece is not directly attached to the surface of the sensing body 1 but the deformation is measured by an indirect method, the directly measured deformation is more accurate in the present invention); and the attachment of the first strain gage 61 to the first surface 14 or/and the second surface 15 is more convenient than the attachment of the first strain gage 61 to the through hole 13.

In an embodiment, as shown in fig. 4 to 7, the through hole 13 includes a first arc hole 131, a connection hole 132, and a second arc hole 133 that are sequentially communicated in the extending direction of the first cantilever 2; at least two first strain gages 61 are attached to the first surface 14 and/or the second surface 15 at positions opposite to the first arc-shaped hole 131 and the second arc-shaped hole 133, respectively. In this embodiment, the first strain gauge 61 is attached to a position opposite to the first and second arc holes 131 and 133, so that the deformation amount of the first surface 14 or/and the second surface 15 of the sensing body 1 at a position opposite to the first and second arc holes 131 and 133 is relatively large, and thus the first strain gauge 61 attached to the position is more sensitive to the measurement of the deformation amount, and thus the weighing result can be determined more accurately.

In an embodiment, as shown in fig. 4 to 7, on a plane parallel to the preset reference plane, the cross sections of the first arc-shaped hole 131 and the second arc-shaped hole 133 are all circular (since the cross section on the preset reference plane is circular, the first arc-shaped hole 131 and the second arc-shaped hole 133 may be cylindrical holes), and the center points of at least two first strain gauges 61 are aligned with the centers of the circular first arc-shaped hole 131 and the circular second arc-shaped hole 133, respectively. That is, in this embodiment, the center point of the first strain gauge 61 (for example, the center point of the rectangular strain gauge is the intersection point of the diagonal lines of the rectangular strain gauge) is aligned with the center points of the first arc hole 131 and the second arc hole 133, so, because the thicknesses of the center points of the first arc hole 131 and the second arc hole 133 at the corresponding positions on the first surface 14 and the second surface 15 are thinnest, when the sensing body 1 is deformed under stress, the deformation amount at the position will be the largest, and therefore, the center point of the first strain gauge 61 is correspondingly set to be aligned with the center point, so that the first strain gauge 61 can more sensitively measure the deformation amount, and further, the accuracy of the weighing result is improved.

Further, as shown in fig. 4 and 5, on a plane parallel to the preset reference plane, the cross section of the connection hole 132 is rectangular, the first arc hole 131 and the second arc hole 133 are symmetrically disposed on opposite sides of the connection hole 132, and the highest height of the circular first arc hole 131 is greater than the height of the rectangular connection hole 132. Optionally, the diameters of the circular first and second arc-shaped holes 131 and 133 are larger than the width of the first strain gauge 61. Meanwhile, the center point of the first strain gauge 61 is aligned with the center of the circular first arc hole 131, and the center of the first arc hole 131 and the center point of the first strain gauge 61 form a first straight line; at this time, along the extending direction of the first cantilever 2, the vertical distance between the connecting point of the hole wall of the first arc-shaped hole 131 and the hole wall of the connecting hole 132 and the first straight line is greater than half the distance between the first strain gauge 61. Thus, in this embodiment, the thickness of the first surface 14 or the second surface 15 corresponding to the position opposite to the center of the first arc hole 131 is thinnest, and the thickness of the first strain gauge 61 is gradually increased from the near to the far as the positions of the first strain gauge are located on both sides of the thinnest position. Similarly, the center point of the first strain gauge 61 is aligned with the center of the second arc-shaped hole 133, and the center of the second arc-shaped hole 133 and the center point of the first strain gauge 61 form a second straight line; at this time, along the extending direction of the first cantilever 2, the vertical distance between the connecting point of the hole wall of the second arc-shaped hole 133 and the hole wall of the connecting hole 132 and the second straight line is greater than half the distance between the first strain gauge 61. Thus, in this embodiment, the thickness of the first surface 14 or the second surface 15 corresponding to the position opposite to the center of the second arc hole 133 is the thinnest, and the thickness of the first strain gauge 61 is gradually increased from the near to the far as the positions of the first strain gauge are located on both sides of the thinnest position. The above arrangement in this embodiment can further improve the accuracy of the weighing result.

In one embodiment, as shown in fig. 6 and 7, the connection hole 132 includes a first transition hole 1321 communicating with the first arc hole 131, a second transition hole 1323 communicating with the second arc hole 133, and a stepped hole 1322 communicating between the first transition hole 1321 and the second transition hole 1323; on a plane parallel to the preset reference plane, the first transition hole 1321 and the second transition hole 1323 are arranged in parallel, the step hole 1322 is arranged perpendicular to the first transition hole 1321, and the width of the step hole 1322 is smaller than or equal to the first preset gap width. That is, the step hole 1322 in fig. 6 and 7 is perpendicular to the first transition hole 1321 and is in a strip shape, and meanwhile, the width of the step hole 1322 is smaller than or equal to the first preset gap width, so the step hole 1322 can also be regarded as a gap, when the second cantilever 3 or the first cantilever 2 receives a pulling pressure, and further, when the sensing main body 1 is deformed, the distance between the opposite sides of the step hole 1322 shown in fig. 6 or fig. 7 will gradually decrease, so when the pulling pressure reaches a certain limit value, the deformation of the sensing main body 1 gradually adheres to the opposite sides of the step hole 1322, at this time, even if the pulling pressure continuously increases, the deformation of the sensing main body 1 will not change greatly, so the torque bending moment deformation of the weighing sensor due to overload will not be caused, and the reliability of the weighing result is improved. In this embodiment, the first preset slit width may be equal to or different from the second preset slit width. The first preset gap width is used for representing the magnitude of overload pulling pressure which can be correspondingly born when the opposite side surfaces of the step hole 1322 are mutually adhered from the distance of the first preset gap width; therefore, the width of the step hole 1322 is set to be smaller than the first preset gap width, so that the opposite sides of the step hole 1322 can be attached before the load cell bears the overload pulling pressure, thereby preventing the load cell from being overloaded and improving the reliability of the weighing result.

Further, as shown in fig. 6 and 7, on a plane parallel to the preset reference plane, the first transition hole 1321 and the second transition hole 1323 are elongated, and the diameter of the circular first arc-shaped hole 131 and second arc-shaped hole 133 is larger than the height of the first transition hole 1321 and the second transition hole 1323; and the diameters of the circular first and second arc-shaped holes 131 and 133 are larger than the width of the first strain gauge 61. Meanwhile, the center point of the first strain gauge 61 is aligned with the center of the circular first arc hole 131, and the center of the first arc hole 131 and the center point of the first strain gauge 61 form a first straight line; at this time, along the extending direction of the first cantilever 2, the vertical distance between the connecting point of the hole wall of the first arc-shaped hole 131 and the hole wall of the first transition hole 1321 and the first straight line is greater than half the distance between the first strain gauge 61. Thus, in this embodiment, the thickness of the first surface 14 or the second surface 15 corresponding to the position opposite to the center of the first arc hole 131 is thinnest, and the thickness of the first strain gauge 61 is gradually increased from the near to the far as the positions of the first strain gauge are located on both sides of the thinnest position. Similarly, the center point of the first strain gauge 61 is aligned with the center of the second arc-shaped hole 133, and the center of the second arc-shaped hole 133 and the center point of the first strain gauge 61 form a second straight line; at this time, along the extending direction of the first cantilever 2, the vertical distance between the connecting point of the hole wall of the second arc-shaped hole 133 and the hole wall of the second transition hole 1323 and the second straight line is greater than half the distance between the first strain gauge 61. Thus, in this embodiment, the thickness of the first surface 14 or the second surface 15 corresponding to the position opposite to the center of the second arc hole 133 is the thinnest, and the thickness of the first strain gauge 61 is gradually increased from the near to the far as the positions of the first strain gauge are located on both sides of the thinnest position. The above arrangement in this embodiment can further improve the accuracy of the weighing result.

In an embodiment, as shown in fig. 4 to 7, on a plane parallel to the preset reference plane, the height of the first cantilever 2 is equal to the height of the second cantilever 3, and the height of the first cantilever 2 is greater than the height of the sensing body 1. That is, when the load cell is applied to the weighing device of the cell processing apparatus, the accuracy will be higher, so that, on the plane parallel to the preset reference plane, the heights of the first cantilever 2 and the second cantilever 3 are made to be greater than the height of the sensing body 1 (i.e., the first cantilever 2 and the second cantilever 3 are made to be thicker), so that the deformation of the first cantilever 2 and the second cantilever 3 can be transferred to the sensing body 1 more quickly to deform, and the accuracy of the first strain gauge 61 attached to the sensing body 1 for measuring the deformation is improved.

In an embodiment, as shown in fig. 8, on a preset reference plane, the height of the first space 4 is smaller than or equal to the body height of the sensing body 1; the preset reference plane is a plane perpendicular to the first surface 14 and parallel to the extending direction of the first cantilever 2; the first surface 14 is a surface of the sensing body 1 opposite to the first cantilever 2, and the first surface 14 is located on an inner side wall of the first space 4; in this embodiment, when the height of the first space 4 is greater than the body height of the sensing body 1, the height of the second space 5 coincides with the height of the first space 4, and thus, the height of the second space 5 is also less than or equal to the body height of the sensing body 1. The strain assembly 6 includes at least two second strain gages 62, at least two second strain gages 62 are attached to the third surface 16 or/and the fourth surface 17 of the inner sidewall of the through hole 13 at intervals, the fourth surface 17 is opposite to and parallel to the third surface 16, and the third surface 16 is parallel to the first surface 14.

In this embodiment, when the height of the first space 4 and the second space 5 is less than or equal to the body height of the sensing body 1, the second strain gauge 62 may be attached to the third surface 16 or the fourth surface 17, or one half of the second strain gauge is attached to the third surface 16, and the other half of the second strain gauge is attached to the fourth surface 17 symmetrically, specifically, as shown in fig. 8, two second strain gauges 62 are disposed on each of the third surface 16 and the fourth surface 17, and the strain assembly 6 includes four second strain gauges 62 in total; however, in the present invention, the strain assembly 6 is not limited to include only four second strain gages 62, but may include four, eight or other numbers of second strain gages 62. In this embodiment, as shown in fig. 8, since the height of the sensing body 1 is large (thick) with respect to the first space 4 and the second space 5, the through hole 13 on the sensing body 1 can be set large, and the first space 4 and the second space 5 are relatively small, so that the operation of attaching the second strain gauge 62 to the third surface 16 and the fourth surface 17 is more convenient, and the deformation of the sensing body 1 can be directly measured by attaching the second strain gauge 62 to the third surface 16 or/and the fourth surface 17, thereby ensuring the accuracy of the finally measured weighing result by the directly measured deformation amount. Preferably, on a plane parallel to the preset reference plane, the cross section of the through hole 13 is rectangular, the height of the first cantilever 2 is equal to the height of the second cantilever 3, and the height of the through hole 13 is greater than the height of the first space 4 and the first cantilever 2. That is, the height of the rectangular through hole 13 is greater than the height of the first space 4 and the first cantilever 2, so that the second strain gauge 62 can be more conveniently attached to the third surface 16 and the fourth surface 17.

The embodiment of the invention also provides a weighing device which comprises the weighing sensor. The weighing device can be a weighing device of the cell processing equipment, and the weighing sensor can ensure stable and reliable weighing results and high precision of the weighing results. The weighing device with the weighing sensor can meet the weighing requirements of high precision and high stability of cell processing equipment.

The above embodiments of the weighing cell of the present invention are merely examples, and are not intended to limit the present invention, any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of the present invention.

Claims (12)

1. A weighing sensor, comprising a sensing body, and a first cantilever and a second cantilever respectively connected to opposite sides of the sensing body; the first cantilever, the second cantilever and the sensing main body are arranged in parallel; the first cantilever is connected to the first end of the sensing main body and extends towards the second end; the second cantilever is connected to the second end of the sensing main body and extends towards the first end; a first space is formed between the first cantilever and the sensing main body, and a second space is formed between the second cantilever and the sensing main body; the height of the first space is equal to the height of the second space;

the sensing main body is provided with a through hole; the weighing sensor further comprises a strain assembly attached to the sensing main body at a position corresponding to the through hole.

2. The load cell of claim 1 wherein the first space has a height above a predetermined datum level that is greater than a body height of the sensing body; the preset reference surface is a surface perpendicular to the first surface and parallel to the extending direction of the first cantilever; the first surface is a surface of the sensing main body opposite to the first cantilever, and is positioned on the inner side wall of the first space;

the strain assembly comprises at least two first strain pieces, wherein the at least two first strain pieces are attached to the first surface or/and the second surface at intervals and are opposite to the through holes; the second surface is a surface of the sensing body opposite to the second cantilever, and the second surface is located on the inner side wall of the second space.

3. The load cell of claim 2 wherein said through-hole comprises a first arcuate hole, a connecting hole and a second arcuate hole in sequential communication along the direction of extension of said first cantilever; at least two first strain gauges are respectively attached to the first surface or/and the second surface at positions opposite to the first arc-shaped holes and the second arc-shaped holes.

4. A load cell according to claim 3 wherein the first and second arcuate apertures each have a circular cross-section in a plane parallel to the predetermined datum plane, the centre points of at least two of the first strain gauges being aligned with the centre of the circular first and second arcuate apertures respectively.

5. The load cell of claim 3 or 4 wherein said connection aperture comprises a first transition aperture in communication with said first arcuate aperture, a second transition aperture in communication with said second arcuate aperture, and a stepped aperture in communication between said first transition aperture and said second transition aperture;

on the plane parallel to the preset reference plane, the first transition hole and the second transition hole are arranged in parallel, the step hole and the first transition hole are arranged vertically, and the width of the step hole is smaller than or equal to the width of the first preset gap.

6. The load cell of claim 3 or 4, wherein the cross section of the connecting hole is rectangular in a plane parallel to the preset reference plane, the first arc-shaped hole and the second arc-shaped hole are symmetrically arranged on two opposite sides of the connecting hole, and the highest height of the circular first arc-shaped hole is larger than the height of the rectangular connecting hole.

7. The load cell of claim 2 wherein the height of said first cantilever is equal to the height of said second cantilever and the height of said first cantilever is greater than the height of said sensing body in a plane parallel to said predetermined datum plane.

8. The load cell of claim 1 wherein the first space has a height on a predetermined datum level that is less than or equal to the body height of the sensing body; the preset reference surface is a surface perpendicular to the first surface and parallel to the extending direction of the first cantilever; the first surface is a surface of the sensing main body opposite to the first cantilever, and is positioned on the inner side wall of the first space;

the strain assembly comprises at least two second strain pieces, wherein the at least two second strain pieces are attached to a third surface or/and a fourth surface of the inner side wall of the through hole at intervals, the fourth surface is opposite to the third surface and is arranged in parallel, and the third surface is parallel to the first surface.

9. The load cell of claim 8 wherein said through hole has a rectangular cross section in a plane parallel to said predetermined reference plane, said first cantilever having a height equal to a height of said second cantilever, said through hole having a height greater than a height of said first space and said first cantilever.

10. The weighing sensor of claim 1, wherein a first limiting portion is disposed at a second end of the first cantilever, a second limiting portion is disposed at a second end of the sensing main body, the first limiting portion is disposed opposite to the second limiting portion, and a first limiting gap is formed between the first limiting portion and the second limiting portion;

the first end of the second cantilever is provided with a third limiting part, the first end of the sensing main body is provided with a fourth limiting part, the third limiting part and the fourth limiting part are arranged oppositely, and a second limiting gap is formed between the third limiting part and the fourth limiting part;

the width of the first limiting gap is equal to that of the second limiting gap, and the width of the first limiting gap is smaller than that of the second preset gap.

11. The load cell of claim 1 further comprising a protective housing mounted on said sensor body and completely covering said through-hole and at least partially covering said first space and said second space.

12. A weighing apparatus comprising a load cell according to any one of claims 1 to 11.