Cantilever beam sensor

Abstract

The utility model relates to the technical field of stress type sensors, and discloses a cantilever beam sensor, which comprises an elastic body, an outer protection sheet, a strain gauge and a group bridge circuit. The elastomer is provided with a mounting groove. The top and the bottom of the mounting groove respectively form a strain area. An outer protection sheet is arranged at the opening of the mounting groove. And the strain gauges and the group bridge circuit are arranged in the mounting groove. The outer side surface of the strain area is provided with a strain groove. A strain gauge is arranged on the inner side face of the same strain area. And the strain gauges are electrically connected with the group bridge circuit. According to the utility model, the electrical apparatus element is placed in the elastic member of the sensor and is protected by the outer protection sheet, so that the risk of damage of external hard objects to the sensor is greatly reduced. And the outer protection sheet made of hardened stainless steel is used, so that additional mechanical protection is provided, electromagnetic interference can be effectively shielded, and the performance stability and the measurement precision of the sensor are improved. All components in the sensor are hidden and fixed, so that the whole sensor is tidier and more attractive in appearance.

Description

Technical Field

[0001] The utility model relates to the technical field of stress type sensors, in particular to a cantilever beam sensor. Background Art

[0002] The traditional double-hole cantilever beam sensor can achieve basic sensing functions by sticking the strain gauge on the outside of the elastomer, but there are many problems in practical applications. First, because the strain gauge, bridge circuit and terminals are all exposed to the outside and only rely on silicone sealing, they are easily damaged by external hard objects. Secondly, this structure lacks electromagnetic shielding function and is easily affected by electromagnetic interference, resulting in unstable sensor performance. Finally, from the appearance point of view, the gluing, bonding and wire arrangement on the outside of the sensor are not beautiful enough.

[0003] In order to solve the above problems, we propose a cantilever beam sensor. Utility Model Content

[0004] The purpose of the utility model is to provide a cantilever beam sensor to solve the problems raised in the above background technology.

[0005] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a cantilever beam sensor, comprising an elastic body, an external protective sheet, a strain gauge and a bridge circuit; the elastic body is provided with a mounting groove; a strain zone is formed at the top and bottom of the mounting groove respectively; an external protective sheet is provided at the opening of the mounting groove; the strain gauge and the bridge circuit are both arranged in the mounting groove; a strain groove is provided on the outer side surface of the strain zone; the strain gauge is provided on the inner side surface of the same strain zone; the strain gauge is electrically connected to the bridge circuit.

[0006] Preferably, each of the two strain zones is provided with at least one strain groove; each of the inner sides of the two strain zones is provided with at least one strain gauge; and the number of the strain gauges is consistent with the number of the strain grooves.

[0007] Preferably, the number of the strain grooves and the number of the strain gauges are both four; two strain grooves are provided on the outer side surface of one strain zone; and two strain gauges are provided on the inner side surface of the same strain zone.

[0008] Preferably, a wire hole is formed on one end surface of the elastic body; the wire hole is connected to the mounting groove; and the wires of the bridge circuit pass through the wire hole.

[0009] Preferably, a connecting hole is opened on the top of the elastomer; the connecting hole passes through the elastomer.

[0010] Preferably, one end of the outer protective sheet is connected to the elastic body via adhesive; and a gap exists between the other end of the outer protective sheet and the opening of the mounting groove.

[0011] Compared with the prior art, the beneficial effects of the utility model are:

[0012] 1. Enhanced durability: By placing the bridge circuit inside the elastic part of the sensor and protecting it with an external protective sheet, the risk of damage to the sensor by external hard objects is greatly reduced.

[0013] 2. Excellent shielding performance: The outer protective sheet made of hardened stainless steel not only provides additional mechanical protection, but also effectively shields electromagnetic interference, thereby improving the performance stability and measurement accuracy of the sensor.

[0014] 3. Beautiful appearance: All components inside the sensor are cleverly hidden and fixed, and no obvious gluing, bonding, or wire arrangement can be seen from the outside, making the entire sensor look neater and more beautiful. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 is a stress diagram of the prior art;

[0016] Figure 2 It is an isometric structural schematic diagram of the utility model;

[0017] Figure 3 It is a schematic diagram of the top view structure of the utility model;

[0018] Figure 4 This is the stress diagram of the present invention.

[0019] In the figure: 1-elastic body, 11-installation groove, 12-strain area, 2-external protection sheet, 3-strain groove, 4-strain gauge. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0021] Figure 1 is a stress diagram of the sensor housing in the prior art. Figure 2 , Figure 3 , Figure 4The utility model provides a technical solution: a cantilever beam sensor, comprising an elastic body 1, an outer protective sheet 2, a strain gauge 4 and a bridge circuit. The elastic body 1 is provided with a mounting groove 11. A strain zone 12 is formed at the top and the bottom of the mounting groove 11 respectively. An outer protective sheet 2 is provided at the opening of the mounting groove 11. The strain gauge 4 and the bridge circuit are both arranged in the mounting groove 11. A strain groove 3 is provided on the outer side surface of the strain zone 12. The strain gauge 4 is provided on the inner side surface of the same strain zone 12. The strain gauge 4 is electrically connected to the bridge circuit.

[0022] The elastic body 1 is provided with a force-bearing surface on the outside, and the elastic body 1 is provided with a mounting groove 11 matching the size of the electrical component and the strain gauge 4. The bridge circuit includes devices such as strain gauges, terminals, and temperature compensation resistors, and the strain gauges 4 and the bridge circuit are directly pasted in the mounting groove 11.

[0023] The position of the strain gauge 4 corresponds to the position of the strain slot 3 .

[0024] The shape of the mounting groove 11 in the present application is a rectangular groove with rounded corners.

[0025] Further, each of the two strain regions 12 is provided with at least one strain groove 3. Each of the inner sides of the two strain regions 12 is provided with at least one strain gauge 4. The number of the strain gauges 4 is the same as the number of the strain grooves 3.

[0026] Furthermore, the utility model preferably has four strain grooves 3 and four strain gauges 4. Two strain grooves 3 are provided on the outer side of one strain zone 12. Two strain gauges 4 are provided on the inner side of the same strain zone 12. In the utility model, each strain zone 12 is provided with two strain grooves 3 and two strain gauges 4. The positions of the strain grooves 3 and the strain gauges 4 correspond to each other.

[0027] like Figure 4 As shown, the strain groove 3 is in the elastic stage when subjected to force, so the deformation of the strain groove 3 changes linearly with the magnitude of the force. The strain gauge 4 is attached to the side wall of the mounting groove 11 corresponding to the inner side of the strain groove 3. The strain gauge 4 is deformed synchronously with the elastic body 1. After the strain gauge 4 is deformed, the resistance value will change, and the output signal will change synchronously, so the output signal can be measured to detect the change of the force.

[0028] Furthermore, a wire hole is formed on one end surface of the elastic body 1 , and the wire hole is connected to the mounting slot 11 , and is used to lead out the wire of the bridge circuit in the mounting slot 11 .

[0029] Furthermore, a connection hole is provided on the top of the elastic body 1 , and the connection hole passes through the elastic body 1 .

[0030] Furthermore, one end of the outer protective sheet 2 is connected to the elastic body 1 by adhesive. There is a gap between the other end of the outer protective sheet 2 and the opening of the mounting groove 11. A small boss is provided at the opening of the mounting groove 11, and a piece of the outer protective sheet 2 made of hardened stainless steel is fixed on the boss. One end of the outer protective sheet 2 is fixed to the boss by bonding, and the other end of the outer protective sheet 2 is in a free hanging state.

[0031] Existing technologies such as Figure 1 As shown in the figure, most of them adopt double-hole external strain gauge structure, with a rated load of 4.0kg and a stress in the deformation zone of 6.212×10 7 N, the yield strength is 2.9×10 8 N.

[0032] The utility model Figure 4 As shown, a packaging structure with the strain gauge 4 attached inside is adopted. The rated load is 4.0 kg, the stress of the strain slot 3 is 5.755×107 N, and the yield force is 2.9×108 N.

[0033] From the above content, it can be seen that the stress conditions at the deformation point are basically the same. Without affecting the normal structural use, all components of the utility model are cleverly hidden and fixed, and no obvious gluing, bonding and wire arrangement can be seen on the outside, making the appearance of the entire sensor more neat and beautiful. By placing the bridge circuit and the strain gauge 4 inside the elastic member 1 and protecting them with the outer protective sheet 2, the risk of damage to the sensor of the utility model by external hard objects is greatly reduced. The outer protective sheet 2 made of hardened stainless steel not only provides additional mechanical protection, but also effectively shields electromagnetic interference, thereby improving the performance stability and measurement accuracy of the sensor of the utility model.

[0034] Working principle:

[0035] First, the elastomer 1 is manufactured, and the mounting groove 11 is machined inside it. Then, the strain gauge 4 and the bridge circuit are precisely pasted in the mounting groove 11, and the strain gauge 4 and the bridge circuit are connected in necessary circuits. Next, the bridge circuit wires are led out through the wire holes. Finally, the outer protective sheet 2 made of hardened stainless steel is fixed on the boss at the opening of the mounting groove 11, ensuring that one end of the mounting groove 11 is firmly fixed and the other end of the mounting groove 11 can swing freely.

[0036] The elastic body 1 is made of a lightweight but high-strength material - aluminum alloy, to ensure that the sensor of the utility model can generate sufficient strain when subjected to force. The strain gauge 4 should be selected from a material with high sensitivity and low hysteresis to ensure accurate measurement results. Among them, the high-sensitivity and low-hysteresis material is 2A12-T4 aluminum alloy, which has undergone solid solution aging heat treatment.

[0037] The terminals and temperature compensation resistors in the bridge circuit should be components with high stability and reliability to ensure the long-term stability of the sensor.

[0038] The outer protective sheet 2 should be made of hardened stainless steel to provide sufficient mechanical strength and electromagnetic shielding effect.

[0039] During the processing and assembly process, the size and position of each component need to be precisely controlled to ensure the performance and reliability of the sensor of the utility model. In particular, the pasting and circuit connection of the strain gauge 4 and the terminals and temperature compensation resistors in the bridge circuit should be carried out strictly in accordance with the prescribed process steps to ensure its accuracy and stability.

[0040] Finally, after completing the assembly and testing of the sensor of the utility model, necessary performance evaluation and calibration should be carried out to ensure that the sensor of the utility model can achieve the expected performance indicators in actual use.

[0041] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be regarded as exemplary and non-restrictive from any point of view, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention. Any reference numeral in a claim should not be regarded as limiting the claim to which it relates.

[0042] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A cantilever beam sensor, characterized in that: The invention comprises an elastic body (1), an outer protective sheet (2), a strain gauge (4) and a bridge circuit; the elastic body (1) is provided with a mounting groove (11); a strain zone (12) is formed at the top and the bottom of the mounting groove (11); an outer protective sheet (2) is provided at the opening of the mounting groove (11); the strain gauge (4) and the bridge circuit are both arranged in the mounting groove (11); a strain groove (3) is provided on the outer side surface of the strain zone (12); the strain gauge (4) is provided on the inner side surface of the same strain zone (12); the strain gauge (4) is electrically connected to the bridge circuit.

2. A cantilever beam sensor according to claim 1, characterized in that: The two strain areas (12) are each provided with at least one strain groove (3); the inner side surfaces of the two strain areas (12) are each provided with at least one strain gauge (4); and the number of the strain gauges (4) is the same as the number of the strain grooves (3).

3. A cantilever beam sensor according to claim 2, characterized in that: The number of the strain grooves (3) and the number of the strain gauges (4) are both four; two strain grooves (3) are provided on the outer side of one strain zone (12); and two strain gauges (4) are provided on the inner side of the same strain zone (12).

4. The cantilever beam sensor according to claim 1, characterized in that: One end surface of the elastic body (1) is provided with a wire hole; the wire hole is connected to the mounting groove (11); and the wire of the bridge circuit passes through the wire hole.

5. The cantilever beam sensor according to claim 1, characterized in that: A connection hole is provided on the top of the elastic body (1); the connection hole passes through the elastic body (1).

6. The cantilever beam sensor according to claim 1, characterized in that: One end of the outer protective sheet (2) is connected to the elastic body (1) via adhesive; and a gap exists between the other end of the outer protective sheet (2) and the opening of the mounting groove (11).

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