LVDT displacement sensor

Abstract

The utility model relates to the technical field of detection, in particular to an LVDT (Linear Variable Differential Transformer) displacement sensor, which comprises an elastic body, the elastic body comprises an L-shaped body and a linear body, the linear body is fixedly connected with the upper end of the L-shaped body, and a circular avoiding groove is arranged at the joint of the linear body and the L-shaped body in a penetrating manner; a first limiting piece, an elastic piece, a measuring piece and an air cylinder are arranged between the linear body and the L-shaped body, the air cylinder is arranged on the side, away from the circular receding groove, of the L-shaped body, a pushing seat is arranged on the linear body, the pushing seat corresponds to a piston rod of the air cylinder, and the pushing seat is arranged on the L-shaped body. And a probe mounting hole is formed in one side, far away from the circular avoiding groove, of the linear body. Through the linkage design of the air cylinder and the pushing seat, the linear body can be actively driven to move outwards to form a preset avoiding included angle before detection, a safe space displacement path is provided for a probe, and probe abrasion or workpiece scratching caused by rigid collision is avoided.

Description

Technical Field

[0001] This utility model relates to the field of detection technology, and specifically to an LVDT displacement sensor. Background Technology

[0002] In the field of industrial automation inspection, LVDT displacement sensors are widely used in scenarios such as dimensional measurement and geometric tolerance inspection of precision workpieces due to their high precision and high reliability. Traditional LVDT displacement sensors typically employ a rigid contact measurement structure, where the probe directly contacts the workpiece surface to acquire displacement signals. However, in actual inspection processes, such sensors suffer from the following technical challenges:

[0003] When sensors are mounted on automated equipment such as robotic arms and coordinate measuring machines for workpiece positioning, the probe is prone to rigid collision with the workpiece during rapid movement due to irregular contours or installation errors on the workpiece surface. This can lead to probe wear, scratches on the workpiece surface, and even damage to the internal structure of the sensor, seriously affecting the safety and reliability of the detection. Utility Model Content

[0004] This invention provides an LVDT displacement sensor to address the problems of existing technologies.

[0005] The objective of this utility model can be achieved through the following technical solution: An LVDT displacement sensor includes an elastic body, the elastic body comprising an L-shaped body and a straight body, the upper ends of the straight body and the L-shaped body being fixedly connected and a circular clearance groove being provided through the connection between the two, a first limiting member, an elastic member, a measuring member and a cylinder being provided between the straight body and the L-shaped body, the cylinder being provided on the side of the L-shaped body away from the circular clearance groove, a push seat being provided on the straight body, the push seat being correspondingly provided with the piston rod of the cylinder, and a probe mounting hole being provided on the side of the straight body away from the circular clearance groove.

[0006] In a further improvement, the straight-shaped body is provided with a first limiting hole, an elastic hole, and a measuring hole from left to right. A first limiting member is provided with an internal thread in the first limiting hole. One end of the first limiting screw passes through the straight-shaped body and a first locking nut is provided on the side close to the straight-shaped body. An elastic member is provided in the elastic hole, and the lower end of the elastic member is provided in the L-shaped body. An embedded sensor cavity is provided in the L-shaped body. A measuring member is provided in the measuring hole, and the lower end of the measuring member is provided in the embedded sensor cavity.

[0007] In a further improvement, a second limiting hole is provided between the elastic hole and the measuring hole. The second limiting hole includes an upper clearance groove and a lower first through hole. A second limiting member is provided in the first through hole. The upper end of the second limiting member is slidably disposed in the first through hole and a limiting seat is provided at the top. The lower end of the second limiting member is threadedly connected to the L-shaped body.

[0008] As a further improvement, a second locking nut is threaded onto the second limiting member, and the second locking nut is located on the upper side of the L-shaped body.

[0009] As a further improvement, a second through hole is provided on the straight body, and the second through hole is connected to the circular clearance groove.

[0010] In a further improvement, a wire cavity is inclinedly arranged inside the L-shaped body, and the wire cavity is connected to the embedded sensor cavity.

[0011] As a further improvement, a triangular clearance groove is provided on the side of the wire cavity away from the in-slot sensor cavity.

[0012] Compared with the prior art, the present invention has the following beneficial effects:

[0013] 1. This utility model uses the linkage design of cylinder and push seat to actively drive the straight body to move outward before detection to form a preset avoidance angle, providing a safe spatial displacement path for the probe. This structure enables the probe to avoid the protrusions or complex contours on the workpiece surface through non-contact pre-positioning during the positioning process of the external moving mechanism, avoiding probe wear or workpiece scratches caused by rigid collision, and significantly improving the safety and reliability of the detection system. It is especially suitable for detection scenarios of high-precision thin-walled workpieces or curved workpieces.

[0014] 2. The elastic component of this utility model utilizes its own elastic restoring force to achieve passive reset without a power source, and can complete the initial position return of the straight body after the cylinder stops driving.

[0015] 3. The first limiting component of this utility model adopts a mechanical hard limiting method. By limiting the maximum travel of the straight body, it effectively prevents overtravel displacement caused by cylinder overload, control error or external impact, and avoids damage caused by rigid contact between the measuring component and the internal structure of the sensor. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of this utility model;

[0017] Figure 2 This is a cross-sectional view of the present invention;

[0018] Figure 3 This is a front view of the present invention.

[0019] In the figure, 1 is an elastic body; 11 is an L-shaped body; 111 is an embedded sensor cavity; 112 is a wire cavity; 113 is a triangular clearance groove; 12 is a straight body; 121 is a first limiting hole; 122 is an elastic hole; 123 is a measuring hole; 124 is a second limiting hole; 1241 is a clearance groove; 1242 is a first through hole; 2 is a first limiting component; 21 is a first locking nut; 3 is an elastic component; 4 is a measuring component; 5 is a cylinder; 51 is a push seat; 61 is a circular clearance groove; 62 is a probe mounting hole; 63 is a second through hole; 7 is a second limiting component; 71 is a limiting seat; 72 is a second locking nut. Detailed Implementation

[0020] In the description of this utility model, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0021] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0022] The following is a description of the embodiments and appendices. Figures 1-3 The technical solution of this utility model will be further described below.

[0023] Example 1

[0024] An LVDT displacement sensor includes: an elastic body 1, the elastic body 1 including an L-shaped body 11 and a straight body 12, the straight body 12 being fixedly connected to the upper end of the L-shaped body 11 and a circular clearance groove 61 being provided through the connection between the two, a first limiting member 2, an elastic member 3, a measuring member 4 and a cylinder 5 being provided between the straight body 12 and the L-shaped body 11, the cylinder 5 being provided on the side of the L-shaped body 11 away from the circular clearance groove 61, a push seat 51 being provided on the straight body 12, the push seat 51 being correspondingly provided with the piston rod of the cylinder 5, and a probe mounting hole 62 being provided on the side of the straight body 12 away from the circular clearance groove 61.

[0025] like Figures 1-3 As shown, the working principle of this utility model is as follows:

[0026] Before workpiece inspection, the piston rod of cylinder 5 extends outward and abuts against the push seat 51, driving the straight body 12 to move away from the L-shaped body 11, so that a preset avoidance angle is formed between the L-shaped body 11 and the straight body 12. At this time, the probe installed in the probe mounting hole 62 is accurately positioned above the workpiece surface to be inspected by the external moving mechanism, avoiding direct collision between the probe and the workpiece during the movement. Subsequently, the piston rod of cylinder 5 retracts, driving the straight body 12 to reset and move towards the L-shaped body 11, so that the probe and the workpiece surface to be inspected make flexible contact, thereby completing the acquisition and detection of displacement signals.

[0027] The first limiting component 2 limits the maximum travel of the straight body 12 by mechanical limiting, preventing damage to the measurement structure caused by excessive displacement and ensuring that the sensor maintains high-precision measurement performance throughout the entire range.

[0028] After the cylinder 5 stops driving, the elastic element 3 uses its elastic restoring force to push the straight body 12 back to its initial position quickly. This passive reset design significantly improves the dynamic response speed of the sensor and meets the efficiency requirements of high-frequency detection scenarios.

[0029] As a further preferred embodiment, the straight body 12 is provided with a first limiting hole 121, an elastic hole 122 and a measuring hole 123 from left to right. A first limiting member 2 is threadedly connected to the first limiting hole 121. One end of the first limiting screw 2 passes through the straight body 12 and a first locking nut 21 is provided on the side close to the straight body 12. An elastic member 3 is provided in the elastic hole 122. The lower end of the elastic member 3 is provided in the L-shaped body 11. An embedded sensor cavity 111 is provided in the L-shaped body 11. A measuring member 4 is provided in the measuring hole 123. The lower end of the measuring member 4 is provided in the embedded sensor cavity 111.

[0030] Specifically, the first limiting screw is adjustable in position through a threaded connection, and the locking nut 21 ensures that the limiting position is stable during operation, preventing the screw from loosening due to vibration, thereby precisely limiting the leftward stroke of the straight body 12 and preventing excessive compression of the elastic element 3; the elastic hole 122 is coaxially set with the spring mounting groove of the L-shaped body 11, and the upper and lower ends of the spring are in rigid contact with the bottom of the hole and the bottom of the groove, respectively, to ensure that the reset force is transmitted along the axis of the body and to avoid movement jamming caused by lateral force; the lower end of the measuring element 4 is inserted into the embedded sensor cavity 111. When the straight body 12 moves, the measuring element 4 moves synchronously and linearly in the sensor cavity, triggering the change of electromagnetic induction signal of the LVDT coil.

[0031] As a further preferred embodiment, a second limiting hole 124 is provided between the elastic hole 122 and the measuring hole 123. The second limiting hole 124 includes an upper clearance groove 1241 and a lower first through hole 1242. A second limiting member 7 is provided in the first through hole 1242. The upper end of the second limiting member 7 is slidably disposed in the first through hole 1242 and a limiting seat 71 is provided at the top end. The lower end of the second limiting member 7 is threadedly connected to the L-shaped body 11.

[0032] Specifically, it is a stepped bolt structure with a threaded section at the lower end (matching the internal thread of the first through hole 1242) and a smooth cylindrical section at the upper end. The top end is fixedly connected to a circular limit seat 71. Through the cooperation of the limit parts at the left and right ends, a complete stroke constraint boundary is formed to prevent the body from being damaged by overtravel due to external impact.

[0033] As a further preferred embodiment, the second limiting member 7 is threaded with a second locking nut 72, which is located on the upper side of the L-shaped body 11. By utilizing the precision adjustment characteristics of the threaded connection, the sensor can be adapted to the range requirements of different detection scenarios.

[0034] As a further preferred embodiment, the straight body 12 is provided with a second through hole 63, which is connected to the circular relief groove 61. Through the second through hole 63, metal fatigue of the straight body 12 is effectively prevented.

[0035] As a further preferred embodiment, the L-shaped body 11 has an inclined wire cavity 112 inside, the wire cavity 112 is connected to the embedded sensor cavity 111, and a triangular clearance groove 113 is provided on the side of the wire cavity 112 away from the embedded sensor cavity 111.

[0036] Specifically, the inclined cavity 112 guides the cable to avoid right-angle bends, and the rounded corners of the outlet and the anti-scratch treatment of the groove eliminate the risk of short circuits caused by cable sheath wear, thus improving the reliability of the sensor in vibration environments.

[0037] The preferred embodiments of this utility model have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of this utility model without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of this utility model through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. An LVDT displacement sensor, characterized in that, The invention includes an elastomer comprising an L-shaped body and a straight body. The upper ends of the straight body and the L-shaped body are fixedly connected, and a circular clearance groove is provided through the connection between the two. A first limiting member, an elastic member, a measuring member, and a cylinder are provided between the straight body and the L-shaped body. The cylinder is located on the side of the L-shaped body away from the circular clearance groove. A push seat is provided on the straight body, and the push seat is correspondingly provided with the piston rod of the cylinder. A probe mounting hole is provided on the side of the straight body away from the circular clearance groove.

2. The LVDT displacement sensor according to claim 1, characterized in that, The straight-shaped body has a first limiting hole, an elastic hole, and a measuring hole arranged sequentially from left to right. A first limiting member is threadedly connected to the first limiting hole. One end of the first limiting member passes through the straight-shaped body and a first locking nut is provided on the side close to the straight-shaped body. An elastic member is provided in the elastic hole, and the lower end of the elastic member is located in the L-shaped body. An embedded sensor cavity is provided in the L-shaped body. A measuring member is provided in the measuring hole, and the lower end of the measuring member is located in the embedded sensor cavity.

3. The LVDT displacement sensor according to claim 2, characterized in that, A second limiting hole is provided between the elastic hole and the measuring hole. The second limiting hole includes an upper clearance groove and a lower first through hole. A second limiting member is provided in the first through hole. The upper end of the second limiting member is slidably disposed in the first through hole and a limiting seat is provided at the top. The lower end of the second limiting member is threadedly connected to the L-shaped body.

4. The LVDT displacement sensor according to claim 3, characterized in that, The second limiting member is threaded with a second locking nut, which is located on the upper side of the L-shaped body.

5. An LVDT displacement sensor according to claim 1, characterized in that, The straight body is provided with a second through hole, which is connected to the circular clearance groove.

6. An LVDT displacement sensor according to claim 2, characterized in that, The L-shaped body has an inclined wire cavity inside, which is connected to the embedded sensor cavity.

7. An LVDT displacement sensor according to claim 6, characterized in that, A triangular clearance groove is provided on the side of the wire cavity away from the in-slot sensor cavity.

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