A zero platform structure for a load cell and a load cell

Abstract

The application provides a zero position platform structure of a load cell, which comprises a shell and at least one mounting platform, wherein the shell is provided with a through cavity along the extension direction between the free end of the pull shaft of the load cell and the connecting end of the pull shaft, and the opening of the cavity close to the connecting end is a first opening; the connecting end is provided with a mounting surface, the elastic sheet of the load cell is arranged on the connecting end, and the end surface of the elastic sheet away from the first opening is in contact with the mounting surface; the mounting platform is protruded from the inner wall of the cavity for assembling the elastic sheet, and the deformation of the elastic sheet changes with the reciprocating movement of the pull shaft under stress; and the elastic sheet is in an initial deformation state when the elastic sheet is in an initial position, wherein the initial position is the position when the end surface of the elastic sheet away from the first opening is coplanar with the end surface of the mounting platform close to the first opening. The problem of inaccurate zero position of the load cell after long time use is solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of load cells, in particular to a zero position platform structure of a load cell and the load cell. BACKGROUND

[0002] A load cell is a device that converts a mass signal into a measurable electrical signal output. There are various types of load cells, among which a strain gauge load cell measures weight by using the principle that the resistance of an electric resistance strain gauge changes when it deforms. In the prior art, the zero position of a load cell is inaccurate after long-term use. SUMMARY

[0003] Therefore, the present application provides a zero position platform structure of a load cell and the load cell, which can solve the above technical problems.

[0004] In a first aspect, the present application provides a zero position platform structure of a load cell, which comprises: a housing and at least one mounting platform, wherein the housing is provided with a through cavity along the extension direction between the free end of the pull shaft of the load cell and the connecting end of the pull shaft, and the opening of the cavity close to the connecting end is a first opening; the connecting end is provided with a mounting surface, the elastic sheet of the load cell is arranged on the connecting end, and the end surface of the elastic sheet away from the first opening is in contact with the mounting surface; the mounting platform is protruded from the inner wall of the cavity for assembling the elastic sheet, and the end surface of the mounting platform close to the first opening is coplanar with the end surface of the mounting surface close to the first opening. After the pull shaft is stressed, the deformation of the elastic sheet changes with the reciprocating movement of the pull shaft. When the elastic sheet is in the initial position, the elastic sheet is in the initial deformation state, wherein the initial position is the position when the end surface of the elastic sheet away from the first opening is coplanar with the end surface of the mounting platform close to the first opening.

[0005] In an embodiment, the zero position platform structure of the load cell further comprises a top shaft, the top shaft is arranged in the cavity and is configured to be movable in the extension direction, the top shaft is connected with the connecting end, and when the top shaft is static, there is a first gap between the end surface of the top shaft away from the first opening and the end surface of the mounting platform close to the first opening in the extension direction, and the first gap is equal to the thickness of the elastic sheet.

[0006] In an embodiment, the top shaft is provided with a mounting groove with internal threads, and the outer wall of the connecting end is provided with threads matched with the internal threads. After the connecting end is assembled into the mounting groove, the first gap is formed between the end surface of the top shaft away from the first opening and the end surface of the mounting surface close to the first opening.

[0007] In one embodiment, the zero position platform structure of the weighing sensor further comprises a cover, the cover is arranged in the cavity, and an assembly groove for assembling a top shaft is arranged along the extension direction, the top shaft is configured to be movable relative to the cover in the assembly groove, and the height of the cover is lower than the height of the mounting platform in the extension direction.

[0008] In one embodiment, the cover comprises a bottom plate, a first protruding rib and a second protruding rib. The first protruding rib is formed on the bottom plate and close to the outer edge of the bottom plate for assembling the cover in the cavity. The second protruding rib is formed on the bottom plate on the same side as the first protruding rib for forming the assembly groove, and a gap is formed between the first protruding rib and the second protruding rib in the direction from the outer edge of the bottom plate to the center of the bottom plate.

[0009] In one embodiment, the assembly groove is provided with a bottom surface at one end close to the first opening, and the elastic sheet is in the initial deformation state when the end surface of the top shaft close to the first opening is in contact with the bottom surface.

[0010] In one embodiment, the assembly groove is a through groove, and the top shaft is provided with a limiting protrusion, and the elastic sheet is in the initial deformation state when the end surface of the limiting protrusion close to the first opening is in contact with the groove opening of the assembly groove away from the first opening.

[0011] In one embodiment, the mounting platform is provided with one or more first assembly holes, and the elastic sheet is assembled to the mounting platform by cooperating the first assembly holes with second assembly holes arranged on the elastic sheet.

[0012] In one embodiment, the mounting platform is further provided with one or more positioning columns, and the positioning columns and positioning holes arranged on the elastic sheet cooperate to realize the positioning between the elastic sheet and the mounting platform.

[0013] In one embodiment, the at least one mounting platform comprises two mounting platforms, the two mounting platforms are distributed in axial symmetry relative to the axis of the pull shaft, and the shapes of the two mounting platforms are fan-shaped.

[0014] In a second aspect, the application further provides a weighing sensor, which comprises the zero position platform structure of any one of the above.

[0015] According to the technical scheme of the application, by assembling the elastic sheet on the mounting platform protruding from the inner wall of the cavity of the weighing sensor, the mounting platform and the elastic sheet are in surface contact, and the mounting surface of the elastic sheet is coplanar with the mounting surface of the mounting platform at zero position, so that the zero position is not easy to drift, thereby improving the measurement accuracy of the weighing sensor. At the same time, since the load bearing member is used as the main force receiving component, the service life of the elastic sheet is improved, and by making the thick elastic body thin, the problem of affecting the service life and measurement accuracy of the weighing sensor caused by the creep of the elastic body in the previous improved scheme is solved. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1Fig. 1 is a structural schematic diagram of a zero position platform structure of a load cell according to an embodiment of the present application.

[0017] Figure 2 Fig. 2 is a sectional view of the zero position platform structure of the load cell according to an embodiment of the present application.

[0018] Figure 3 Fig. 3 is a sectional view of the zero position platform structure of the load cell according to an embodiment of the present application.

[0019] 1 - housing; 11 - first opening; 2 - mounting platform; 21 - first assembly hole; 22 - positioning column; 3 - pull shaft; 31 - free end; 32 - connecting end; 4 - elastic sheet; 5 - load bearing; 6 - top shaft; 61 - limiting protrusion; 7 - cover; 71 - bottom plate; 72 - first convex rib; 73 - second convex rib; 74 - bottom surface. DETAILED DESCRIPTION

[0020] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments of the present application.

[0021] The load cell mainly includes a housing, a pull shaft, and an elastic sheet on which strain gauges are mounted. One end of the pull shaft is connected to the elastic sheet, and the other end is used to connect a load to be weighed. One end of the elastic sheet is connected to the housing, and the other end is connected to the pull shaft. When the load is connected to the pull shaft, the pull shaft drives the elastic sheet to deform, so that the weight of the load can be obtained according to the change of the resistance measured by the strain gauges on the elastic sheet. Since the elastic sheet is the force-bearing element that mainly bears the external force on the pull shaft in the load cell, the elastic sheet needs a certain thickness to ensure the rigidity requirement, and the thicker elastic sheet will produce creep after long-term use, thereby affecting the service life and accuracy of the load cell.

[0022] For example, the load cell can use a particularly thick elastic body as a carrier of the resistance strain gauges. The elastic body bears the external force on the load cell as the main force-bearing component and produces a strain on the surface, so that the resistance strain gauges pasted on the surface of the elastic body complete the conversion from strain to electrical signal, thereby realizing the weighing of the load cell. However, the elastic body is prone to plastic deformation after repeated stress, which affects the service life of the load cell, or is prone to large creep, which affects the measurement accuracy of the load cell.

[0023] In order to improve the service life and precision of the load sensor, the embodiment of the present application also designs a load bearing member with elasticity to bear the majority of the external force applied to the pull shaft, so that a thinner elastic sheet can be used to measure the weight. Based on the structural improvement of the new load sensor, the zero platform structure of the new load sensor needs to be newly designed.

[0024] Figures 1-3 The structure of the zero platform structure of the load sensor provided by the embodiment of the present application is shown.

[0025] As Figure 1 The embodiment of the present application provides a zero platform structure of a load sensor, which comprises a shell 1 and at least one mounting platform 2, wherein the shell 1 is provided with a through cavity along the extension direction between the free end 31 of the pull shaft 3 of the load sensor and the connecting end 32 of the pull shaft 3, and the opening of the cavity close to the connecting end 32 is a first opening 11. The connecting end 32 is provided with a mounting surface, and the elastic sheet 4 of the load sensor is arranged on the connecting end 32, and the end surface of the elastic sheet 4 away from the first opening 11 is in contact with the mounting surface; the mounting platform 2 is protruded on the inner wall of the cavity for assembling the elastic sheet 4, and the end surface of the mounting platform 2 close to the first opening 11 is coplanar with the end surface of the mounting surface close to the first opening 11. After the pull shaft 3 is stressed, the deformation of the elastic sheet 4 changes with the reciprocating movement of the pull shaft 3, and when the elastic sheet 4 is in the initial position, the elastic sheet 4 is in the initial deformation state, wherein the initial position is the position when the end surface of the elastic sheet away from the first opening is coplanar with the end surface of the mounting platform close to the first opening.

[0026] Specifically, the connecting end 32 of the pull shaft 3 refers to the end of the pull shaft 3 mounted to the zero platform structure and movable relative to the zero platform structure in the extension direction of the pull shaft 3; the free end 31 of the pull shaft 3 refers to the end of the pull shaft 3 extending out of the shell 1, and the free end 31 is stressed, and the hook or ring can be arranged on the free end 31, and the object to be measured is hung on the free end 31, and the gravity of the object to be measured is the external force applied to the free end 31. Moreover, the gravity of the object to be measured is mainly borne by the load bearing member 5, wherein the load bearing member 5 can adopt a disc spring assembly or other elastic member; the elastic sheet 4 is connected to the connecting end 32 of the pull shaft 3 and the zero platform structure, and will be deformed according to the movement of the connecting end 32 of the pull shaft 3.

[0027] When the free end 31 of the pull shaft 3 is not hung with the measured object, the free end 31 of the pull shaft 3 is not forced, the connecting end 32 of the pull shaft 3 is not moved, at this time, the elastic sheet 4 is in the initial deformation state. The end face of the elastic sheet 4 away from the first opening 11 is coplanar with the end face of the mounting platform 2 close to the first opening 11, the elastic sheet 4 will not have a change in shape, and the weighing sensor displays zero, that is, at zero position. When the free end 31 of the pull shaft 3 is hung with the measured object, the free end 31 of the pull shaft 3 is forced, the connecting end 32 of the pull shaft 3 moves towards the free end 31, and under the action of external force, the load bearing 5 on the pull shaft 3 is compressed as the main force component, the elastic sheet 4 is deformed under the driving of the connecting end 32 of the pull shaft 3, that is, the end face of the elastic sheet 4 away from the first opening 11 is not coplanar with the end face of the mounting platform 2 away from the first opening 11, the strain field generated by the deformation of the elastic sheet 4 makes the strain sheet attached to the elastic sheet 4 convert the strain into an electrical signal output, and the weight of the measured object is obtained.

[0028] It can be understood that the initial deformation state of the elastic sheet 4 refers to the state in which the elastic sheet 4 begins to deform, and in an ideal state, the elastic sheet 4 does not deform in this initial state, but due to the allowable error in the processing of parts, the elastic sheet 4 will have a slight deformation, and this slight deformation has little effect on the service life of the elastic sheet 4. In general, the elastic sheet 4 is in the same initial deformation state each time it is in the initial position.

[0029] The elastic sheet 4 is fixed on the zero position mounting platform 2 protruding on the inner wall of the cavity of the weighing sensor, so that the contact surface of the elastic sheet 4 and the mounting platform 2 is coplanar when the weighing sensor is at zero position, so that the zero position is not easy to drift, thereby improving the measurement accuracy. Since the load bearing 5 is used as the main force component, the service life of the elastic sheet 4 is improved, and by making the thick elastic body thin, the problem of the creep of the elastic body affecting the service life and measurement accuracy of the weighing sensor in the previous improvement scheme is solved.

[0030] The zero position platform structure of the above-mentioned weighing sensor can further include a top shaft 6, the top shaft 6 is arranged in the cavity and is configured to be movable in the extension direction, the top shaft 6 is connected with the connecting end 32, and when the top shaft 6 is static, there is a first gap between the end face of the top shaft 6 away from the first opening 11 and the end face of the mounting platform 2 close to the first opening 11 in the extension direction, and the first gap is equal to the thickness of the elastic sheet 4. That is, the end face of the elastic sheet 4 away from the first opening 11 is coplanar with the mounting surface on the pull shaft 3 and the end face of the mounting platform 2 towards the first opening 11, and the end face of the elastic sheet 4 away from the first opening 11 is coplanar with the end face of the top shaft 6 away from the first opening 11. It can be further understood that the elastic sheet 4 is assembled in the first gap formed by the top shaft 6, the mounting boss and the mounting surface.

[0031] The top shaft 6 can move in the cavity in the extension direction of the pull shaft 3, and after the connecting end 32 of the pull shaft 3 is assembled to the top shaft 6, the movement of the connecting end 32 of the pull shaft 3 in the extension direction of the pull shaft 3 is also realized; the top shaft 6 and the connecting end 32 of the pull shaft 3 are made in a split form, which not only improves the assembly efficiency between the two parts, but also simplifies the process of assembling the elastic sheet 4 to the connecting end 32 of the pull shaft 3.

[0032] Regarding how to realize the connection of the pull shaft 3 and the elastic sheet 4 and the assembly between the pull shaft 3 and the top shaft 6, in an embodiment, the top shaft 6 is provided with an internally threaded mounting groove, and the outer wall of the connecting end 32 is provided with threads matched with the internal threads, and after the connecting end 32 is assembled into the mounting groove, a first gap is formed between the end face of the top shaft 6 away from the first opening 11 and the end face of the mounting face close to the first opening 11. This structure is simple, convenient for early part production and processing and late part assembly, and saves production cost. It should be understood that the connection mode of the top shaft 6 and the connecting end 32 of the pull shaft 3 is not limited to the above scheme, and other modes such as clamping can also be used, which can be selected according to actual needs.

[0033] Specifically, the elastic sheet 4 is assembled in the first gap, and the elastic sheet 4 is in an initial deformation state. For example, first, the elastic sheet 4 is assembled on the end face of the mounting platform 2 close to the first opening 11, that is, the end face of the elastic sheet 4 away from the first opening 11 is in contact with the end face of the mounting platform 2 close to the first opening 11. Secondly, by means of the mounting hole on the elastic sheet 4, the elastic sheet 4 is sleeved on the connecting end 32 of the pull shaft 3, and the face of the elastic sheet 4 away from the first opening 11 is in contact with the end face of the mounting face on the pull shaft 3 close to the first opening 11. Then, by means of the threads on the connecting shaft matched with the internal threads in the mounting groove of the top shaft 6, the connecting shaft is screwed into the mounting groove and a first gap is kept between them, that is, after assembly, the end face of the elastic sheet 4 close to the first opening 11 is coplanar with the end face of the top shaft 6 away from the first opening 11, and a first gap is formed between the end face of the top shaft 6 away from the first opening 11 and the end face of the mounting platform 2 close to the first opening 11, and at this time the elastic sheet 4 is in an initial deformation state, that is, when the assembly is completed, the display of the load cell is zero, that is, under the action of no external force, the load cell is in zero position.

[0034] The zero position platform structure of the load cell described above can also include a cover 7, which is arranged in the cavity and is provided with an assembly groove along the extension direction for assembling the top shaft 6, and the top shaft 6 is configured to be movable in the assembly groove relative to the cover 7, and the height of the cover 7 in the extension direction is lower than the height of the mounting platform 2. The shell 1 is arranged in the cavity by means of the cover 7, which is simple in design, easy to realize and reduces product cost.

[0035] In one embodiment, the cover 7 comprises a bottom plate 71, a first protruding rib 72 and a second protruding rib 73. The first protruding rib 72 is formed on the bottom plate 71 and is close to the outer edge of the bottom plate 71 for assembling the cover 7 in the cavity. The second protruding rib 73 is formed on the bottom plate 71 on the same side as the first protruding rib 72 for forming an assembly groove with a gap between the first protruding rib 72 and the outer edge of the bottom plate 71 to the center of the bottom plate 71.

[0036] The design of forming the first protruding rib 72 and the second protruding rib 73 on the same side of the bottom plate 71 in the above-mentioned scheme not only realizes the assembly between the cover 7 and the cavity and the assembly between the cover 7 and the top shaft 6, but also reduces the weight of the cover 7, thereby improving the portability of the zero-position platform structure.

[0037] In one embodiment, the cross section of the bottom plate 71 is circular. The first protruding rib 72 is annular, and the second protruding rib 73 is annular. At least one reinforcing rib connecting the first protruding rib 72 and the second protruding rib 73 is arranged in the gap between the first protruding rib 72 and the second protruding rib 73. The design of the reinforcing rib improves the overall strength of the cover 7. It should be understood that the structure of the first protruding rib 72 and the second protruding rib 73 is not limited to the above-mentioned annular structure, and can be designed according to actual needs, such as arranging a limiting step on the first protruding rib 72 for strengthening the connection strength between the cover 7 and the cavity or arranging an operation groove on the first protruding rib 72 for facilitating disassembly and installation of the cover 7, or arranging an end face on the second protruding rib 73 which is adapted to the structure of the top shaft 6 for facilitating the assembly between the assembly groove and the top shaft 6.

[0038] As shown in FIG. 1, the top shaft 6 is designed to correspond to the cover 7 of different structures. Figures 2-3 As shown in FIG. 1, the top shaft 6 is designed to correspond to the cover 7 of different structures. Figure 2 In one embodiment, the assembly groove is provided with a bottom surface 74 close to one end of the first opening 11, and when the end face of the top shaft 6 close to the first opening 11 is in contact with the bottom surface 74, the elastic sheet 4 does not deform. This structure design is simple, facilitates processing and assembly between parts, and improves production efficiency.

[0039] Specifically, when the free end 31 of the pull shaft 3 is not under stress, the top shaft 6 does not move relative to the shell 1. At this time, under the pre-tightening force of the load bearing 5, the end face of the top shaft 6 close to the first opening 11 is in contact with the bottom surface 74 of the assembly groove of the cover 7, and the bottom surface 74 limits the route of the top shaft 6 in the direction towards the connecting end 32, so that the top shaft 6 cannot continue to move in this direction.

[0040] As shown in FIG. 1, the top shaft 6 is designed to correspond to the cover 7 of different structures. Figure 3As shown, in another embodiment, the assembly groove is a through groove, the top shaft 6 is provided with a limiting protrusion 61, when the end face of the limiting protrusion 61 close to the first opening 11 contacts with the groove opening of the assembly groove away from the first opening 11, the elastic sheet 4 is in the initial deformation state. This structure is simple in design, convenient for processing and assembly between parts, and improves production efficiency.

[0041] Specifically, when no external force is applied to the free end 31 of the pull shaft 3, under the action of the pre-tightening force of the load bearing 5, the top shaft 6 does not move relative to the shell 1, and the limiting protrusion 61 limits the movement of the top shaft 6 in the direction of the connecting end 32, so that it cannot continue to move in this direction.

[0042] In one embodiment, the mounting platform 2 is provided with one or more first assembly holes 21, which cooperate with the second assembly holes provided on the elastic sheet 4 to assemble the elastic sheet 4 to the mounting platform 2, for example, the elastic sheet 4 is assembled to the mounting platform 2 by using screws, which is convenient for disassembly.

[0043] The mounting platform 2 is a boss formed on the inner wall of the cavity of the shell 1 and extending towards the center of the cavity. The embodiments of the present application do not specifically limit the structure of the boss, which can be a closed-loop integral structure distributed circumferentially along the inner wall of the cavity, or a split structure with multiple bosses provided on the inner wall of the cavity. The structure can be selected according to the specific structure of the elastic sheet 4, improving the applicability of the structure. It can be understood that the structure of the mounting platform 2 is adapted to the structure of the connection between the mounting platform 2 and the elastic sheet 4, so that the fixation of the elastic sheet 4 relative to the shell 1 can be completed without affecting the deformation of the elastic sheet 4.

[0044] In one embodiment, the mounting platform 2 is further provided with one or more positioning columns 22, which cooperate with the positioning holes provided on the elastic sheet 4 to realize the positioning between the elastic sheet 4 and the mounting platform 2. Before fixing the elastic sheet 4 to the mounting platform 2, the elastic sheet 4 is placed on the mounting platform 2 through the positioning column 22, improving the assembly efficiency and assembly accuracy.

[0045] In an optional embodiment, the first assembly hole 21 on the mounting platform 2 is provided with one, and correspondingly, the second assembly hole on the elastic sheet 4 is provided with one; the positioning column 22 on the mounting platform 2 is provided with two, which are close to the first assembly hole 21 and are respectively and symmetrically distributed relative to the first assembly hole 21, and correspondingly, the positioning hole on the elastic sheet 4 is provided with two, which are close to the second assembly hole and are respectively and symmetrically distributed relative to the second assembly hole. The design of two positioning holes further improves the assembly efficiency of the elastic sheet 4. It can be understood that the design of the first assembly hole 21 and the positioning column 22 is not limited to the above scheme, and can be specifically designed according to the structure of the elastic sheet 4.

[0046] In an optional embodiment, the inner diameter of the positioning hole arranged on the elastic sheet 4 is smaller than the inner diameter of the second assembly hole arranged on the elastic sheet 4. The assembly efficiency of the elastic sheet 4 is improved without affecting the strength of the elastic sheet 4.

[0047] In an embodiment, the at least one mounting platform 2 comprises two mounting platforms 2, which are distributed in axial symmetry with respect to the axis of the pull shaft 3, and the shapes of the two mounting platforms 2 are fan-shaped. When the elastic sheet 4 is centrosymmetric in shape with respect to the connecting end 32 of the pull shaft 3, the outer edge of the elastic sheet 4 can be mounted on the symmetrical mounting platforms 2, so that the stress of the elastic sheet 4 is uniform, that is, the measurement accuracy of the load cell is improved, and the service life of the load cell is also improved. It should be understood that the number of mounting platforms 2 can be designed according to the specific structure of the elastic sheet 4, which increases the applicability of the zero platform structure.

[0048] The present application also provides a load cell comprising the zero platform structure of the load cell in the above-mentioned solution, which will not be described here again.

[0049] The load cell comprises a housing 1, a pull shaft 3, an elastic sheet 4 and a load carrier 5, wherein the housing 1 is a hollow cavity provided with an opening; one end of the pull shaft 3 is a free end 31, and the other end of the pull shaft 3 is a connecting end 32, wherein the connecting end 32 is arranged in the hollow cavity, the free end 31 extends out of the opening and protrudes from the housing 1, and the pull shaft 3 can move in the axial direction with respect to the hollow cavity; the elastic sheet 4 is arranged in the hollow cavity and can be deformed with the movement of the pull shaft 3; the load carrier 5 is arranged in the hollow cavity and located between the free end 31 and the connecting end 32, and under the effective action of an external force applied to the free end 31, the load carrier 5 is compressed under stress, and at the same time, the pull shaft 3 moves and drives the elastic sheet 4 to move and deform; wherein the effective action is the component of the external force in the direction parallel to the direction in which the pull shaft 3 extends. The design of the load cell of the embodiment of the present application solves the problem that the service life or the measurement accuracy of the load cell is affected by the elastic body.

[0050] In an embodiment, the housing of the load cell and the housing of the zero platform structure can be an integral structure or a split structure, which can be designed according to actual needs, thereby increasing the adaptability of the product.

[0051] In the description of the present application, the description of the terms "one embodiment", "some embodiments", "an example", etc. means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are contained in at least one embodiment or example of the present application. In the present description, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0052] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0053] In addition, the terms "first", "second", etc. are used herein only to describe the different features and do not imply a relative importance or a specific order of the features so indicated. Thus, a feature defined with the term "first" can implicitly or explicitly include at least one of the features so defined.

[0054] The above description is merely illustrative of the application, and is not intended to limit the application. Any modification or equivalent arrangement within the scope of the application, falling within the principles of the application and its patentable scope, should be included in the scope of the application.

Claims

1. A zero-position platform structure for a weighing sensor, characterized in that, include: The housing has a through cavity extending along the direction between the free end of the pull shaft of the load cell and the connecting end of the pull shaft, and the opening of the cavity near the connecting end is a first opening; the connecting end has a mounting surface, and the elastic sheet of the load cell is disposed on the connecting end, with the end face of the elastic sheet away from the first opening contacting the mounting surface. At least one mounting platform protrudes from the inner wall of the cavity for assembling the elastic sheet, and the end face of the mounting platform near the first opening is coplanar with the end face of the mounting surface near the first opening; After the pull shaft is subjected to force, the elastic sheet deforms as the pull shaft reciprocates. When the elastic sheet is in the initial position, the elastic sheet is in the initial deformation state, wherein the initial position is the position where the end face of the elastic sheet away from the first opening is coplanar with the end face of the mounting platform close to the first opening. Wherein, the connecting end of the pull shaft refers to the end of the pull shaft that is installed on the zero-position platform structure and can move relative to the zero-position platform structure in the extension direction of the pull shaft, and the free end of the pull shaft refers to the end of the pull shaft that extends out of the housing. The free end of the pull shaft can be subjected to external force. The load-bearing component of the weighing sensor is disposed in the cavity and located between the free end of the pull shaft and the connecting end of the pull shaft. Under the effective force of the external force applied to the free end of the pull shaft, the load-bearing component is compressed, and at the same time, the pull shaft moves and drives the elastic sheet to move and deform.

2. The zero-position platform structure according to claim 1, characterized in that, It also includes a top shaft, which is disposed in the cavity and configured to be movable in the extension direction. The top shaft is connected to the connecting end, and when the top shaft is stationary, there is a first gap in the extension direction between the end face of the top shaft away from the first opening and the end face of the mounting platform near the first opening, and the first gap is equal to the thickness of the elastic sheet.

3. The zero-position platform structure according to claim 2, characterized in that, The top shaft is provided with an internally threaded mounting groove. The outer wall of the connecting end is provided with a thread that mates with the internal thread. After the connecting end is assembled into the mounting groove, the first gap is formed between the end face of the top shaft away from the first opening and the end face of the mounting surface near the first opening.

4. The zero-position platform structure according to claim 2, characterized in that, It also includes a cover disposed in the cavity and having a mounting groove for assembling the top shaft along the extending direction. The top shaft is configured to move relative to the cover within the mounting groove, and the height of the cover in the extending direction is lower than the height of the mounting platform.

5. The zero-position platform structure according to claim 4, characterized in that, The cap includes: Base plate, A first rib is formed on the base plate and near the outer edge of the base plate for assembling the cover into the cavity; A second rib is formed on the base plate on the same side as the first rib, for forming the mounting groove, and a gap is formed between the first rib and the base plate in the direction from the outer edge of the base plate to the center of the base plate.

6. The zero-position platform structure according to claim 4, characterized in that, The assembly groove has a bottom surface at one end near the first opening. When the end face of the top shaft near the first opening contacts the bottom surface, the elastic sheet is in the initial deformation state.

7. The zero-position platform structure according to claim 4, characterized in that, The assembly groove is a through groove, and the top shaft is provided with a limiting protrusion. When the end face of the limiting protrusion near the first opening contacts the groove opening of the assembly groove away from the first opening, the elastic sheet is in the initial deformation state.

8. The zero-position platform structure according to any one of claims 1-7, characterized in that, The mounting platform is provided with one or more first mounting holes, which cooperate with the second mounting holes provided on the elastic sheet to assemble the elastic sheet onto the mounting platform.

9. The zero-position platform structure according to claim 8, characterized in that, The mounting platform is also provided with one or more positioning posts, which cooperate with the positioning holes provided on the elastic sheet to realize the positioning between the elastic sheet and the mounting platform.

10. The zero-position platform structure according to any one of claims 1-7, characterized in that, The at least one mounting platform includes two mounting platforms, which are symmetrically distributed with respect to the axis of the pull shaft, and the two mounting platforms are fan-shaped.

11. A weighing sensor, characterized in that, The zero-position platform structure of the weighing sensor as described in any one of claims 1-10.

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