Displacement amplification mechanism for improving resolution and measurement precision of displacement sensor

Abstract

The utility model discloses a displacement amplification mechanism for improving the resolution and measurement precision of a displacement sensor, and relates to the technical field of measurement. Comprising a main body, a sliding rod and an electromechanical conversion unit, and the electromechanical conversion unit comprises a fixed part and a sliding part which are in sliding fit; the electromechanical conversion unit is arranged in the body, one end of the sliding rod is inserted in the body in a sliding mode and fixedly connected with a sliding part in the electromechanical conversion unit, and the other end of the sliding rod extends out of the end of the body. The gear carrier is mounted at the end of the main body; a change gear set is mounted at one end, far away from the main body, of the gear carrier; the sliding sleeve sleeves the outer side of the gear frame and is in sliding fit with the outer wall of the gear frame, and a second rack is fixedly arranged on the inner wall of the sliding sleeve; a large gear and a small gear in the change gear set are meshed with the first rack and the second rack respectively. According to the utility model, the displacement input by the sliding sleeve can be amplified, after the displacement is amplified, the resolution of the electromechanical conversion unit is increased in equal proportion, and the measurement precision of the displacement sensor is correspondingly improved.

Description

Technical Field

[0001] This utility model relates to the field of measurement technology, and in particular to a displacement amplification mechanism for improving the resolution and measurement accuracy of displacement sensors. Background Technology

[0002] A displacement sensor is a commonly used component for measuring linear displacement. Its structure includes a main body and a sliding rod. The sliding rod is slidably installed inside the main body. When the sliding rod slides inside the main body, the electromechanical conversion element inside the main body can convert the mechanical motion of the sliding rod into a corresponding electrical signal, thereby completing the acquisition of the displacement signal.

[0003] The measurement accuracy of displacement sensors is limited by the working principle of their internal electromechanical conversion components, making it difficult to significantly improve. Therefore, it is necessary to design a displacement amplification mechanism based on the displacement sensor to improve its resolution and measurement accuracy. Utility Model Content

[0004] This invention provides a displacement amplification mechanism for improving the resolution and measurement accuracy of a displacement sensor. The purpose is to improve the measurement accuracy of the displacement sensor by amplifying the input displacement.

[0005] The technical problem solved by this utility model is achieved by the following technical solution: This utility model provides a displacement amplification mechanism for improving the resolution and measurement accuracy of a displacement sensor, including a main body, a slide rod and an electromechanical conversion unit. The electromechanical conversion unit includes a fixed part and a sliding part, and the two are slidably engaged.

[0006] The main body is a long, narrow shell. The electromechanical conversion unit is located inside the main body, and the fixing part in the electromechanical conversion unit is fixedly connected to the inside of the main body.

[0007] The slide rod has one end slidably inserted into the main body and fixedly connected to the sliding part in the electromechanical conversion unit, and the other end extends out from the end of the main body, and a first toothed rack is machined on the outer side of the extended end;

[0008] The gear carrier is installed at the end of the main body. A gear set is installed on the end of the gear carrier away from the main body. Each gear set includes a large gear and a small gear, and the large gear and the small gear are mounted on the same rotating shaft.

[0009] A sliding sleeve is fitted onto the outside of the gear carrier and slides against the outer wall of the gear carrier. A second rack is fixedly installed on the inner wall of the sliding sleeve.

[0010] The large gear and small gear in the gear train mesh with the first rack and the second rack, respectively.

[0011] As a preferred embodiment, the gear carrier is inserted from the end of the main body and can be locked and fixed by the first bolt. At the same time, a second bolt is installed on the side of the sliding sleeve, and the sliding sleeve can be fixed to the gear carrier by the second bolt.

[0012] As a preferred embodiment, in the electromechanical conversion unit, the fixed part is a resistor, and the sliding part is a sliding contact. The resistor and the sliding contact are respectively connected to an external circuit through cables. When the slide rod slides relative to the main body, the sliding contact slides along the resistor, causing the resistance value of the connected circuit to change accordingly, thereby converting the mechanical signal into an electrical signal.

[0013] As a preferred embodiment, the transmission gear set consists of two sets, which are symmetrically arranged on both sides of the slide bar.

[0014] As a preferred embodiment, the outer diameters of the main body and the sliding sleeve are the same.

[0015] The beneficial effects of this utility model are:

[0016] 1. This utility model incorporates a variable speed gear set in a traditional linear displacement sensor. Through the cooperation of the two gears of different sizes and the corresponding rack in the variable speed gear set, the displacement input by the sliding sleeve can be amplified. After amplification, the displacement of the sliding rod and the sliding part is greatly increased, thereby realizing displacement amplification. After displacement amplification, the resolution of the electromechanical conversion unit increases proportionally, and the measurement accuracy of the displacement sensor is also improved accordingly.

[0017] 2. In practice, increased precision often comes at the cost of reduced range. To balance high precision and large range in various applications, this invention offers two selectable fits between the gear carrier and the main body, and between the gear carrier and the sliding sleeve: a screw-fixed fit and a sliding fit. Based on this design, by separately fixing the gear carrier to the main body or separately fixing the gear carrier to the sliding sleeve, this application can switch between high and low precision to adapt to different application scenarios. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the overall structure of this utility model.

[0019] Figure 2 yes Figure 1 A magnified view of a portion of point A in the middle.

[0020] In the diagram: 1. Cable; 2. Main body; 3. Sliding part; 4. Fixing part; 5. Slide rod; 6. Gear frame; 7. Sliding sleeve; 8. Pinion; 9. Gear; 10. First rack; 11. Second rack; 12. First bolt; 13. Second bolt. Detailed Implementation

[0021] The present invention will be further described below with reference to the accompanying drawings.

[0022] like Figure 1 As shown, this embodiment includes a main body 2, a slide bar 5, and an electromechanical conversion unit. The electromechanical conversion unit includes a fixed part 4 and a sliding part 3, which are slidably engaged.

[0023] like Figure 1 As shown, in this embodiment, the main body 2 is an aluminum alloy extruded profile shell with an axial through cavity, and stepped mounting stops are provided at both ends. The electromechanical conversion unit is fixed to the inner cavity of the main body 2 by epoxy resin encapsulation. This unit consists of a fixing part 4 and a sliding part 3, which are coaxially slidingly engaged.

[0024] like Figure 1 , 2 As shown, in this embodiment, the slide rod 5 is made of nitrided stainless steel. One end of it passes through the self-lubricating bearing at the front end of the main body 2 and is rigidly connected to the sliding part 3. The other end extends to the outside of the main body 2 and is machined with a first rack 10. The sliding stroke of the slide rod 5 is limited by a mechanical limiting block provided in the inner cavity of the main body 2.

[0025] like Figure 1 , 2 As shown, in this embodiment, the gear carrier 6 is installed at the end of the main body 2. Two sets of variable speed gear sets are symmetrically arranged on the end of the gear carrier 6 away from the main body 2. Each variable speed gear set includes a large gear 9 and a small gear 8. The two gears are fixed on the same hardened steel shaft by interference fit, forming a transmission ratio of 2:5.

[0026] like Figure 1 , 2 As shown, in this embodiment, the sliding sleeve 7 is fitted onto the outer side of the gear carrier 6 and slides against the outer wall of the gear carrier 6. A second rack 11 is fixedly installed on the inner wall of the sliding sleeve 7, forming a clearance fit with the guide rail on the outer side of the gear carrier 6. The large gear 9 and small gear 8 in the gear set mesh with the first rack 10 and the second rack 11, respectively. The outer diameter tolerance of the mating section between the main body 2 and the sliding sleeve 7 is controlled at H7 / g6 grade to ensure coaxiality ≤0.02mm.

[0027] In practice, improved accuracy often comes at the cost of reduced range. To balance high precision and large range in various applications, in this invention, the gear carrier 6 is inserted from the end of the main body 2 and secured by a first bolt 12. Simultaneously, a second bolt 13 is mounted on the side of the sliding sleeve 7, allowing it to be fixed to the gear carrier 6. This provides two selectable fits between the gear carrier 6 and the main body 2, and between the gear carrier 6 and the sliding sleeve 7: a screw-fixed fit and a sliding fit. This design allows the invention to switch between high and low precision to adapt to different application scenarios.

[0028] Specifically:

[0029] When the gear carrier 6 is fixedly engaged with the main body 2 and the gear carrier 6 is slidably engaged with the sliding sleeve 7, the displacement of the sliding sleeve 7 is amplified by the speed-changing gear set and transmitted to the sliding rod 5, thereby improving the overall resolution and measurement accuracy of the electromechanical conversion unit and the displacement sensor. At this time, the present invention is in a high-precision, small-range operating state.

[0030] When the gear carrier 6 is in sliding engagement with the main body 2 and the gear carrier 6 is in fixed engagement with the sliding sleeve 7, the sliding sleeve 7, the gear carrier 6 and the sliding rod 5 move synchronously. The displacement of the sliding sleeve 7 is the same as the displacement of the sliding rod 5. At this time, the present invention is in a low-precision, high-range operation state.

[0031] like Figure 1 As shown in this embodiment, in the electromechanical conversion unit, the fixed part 4 is a resistor (wire-wound precision resistor), and the sliding part 3 is a sliding contact (silver alloy sliding contact). The resistor and the sliding contact are respectively connected to the external circuit through the cable 1. When the slide rod 5 slides relative to the main body 2, the sliding contact slides along the resistor, causing the resistance value of the connected circuit to change accordingly, thereby converting the mechanical signal into an electrical signal.

[0032] In this embodiment, the outer diameter of the main body 2 and the sliding sleeve 7 are the same, which makes it easy to install the whole in a narrow diameter space.

[0033] In some embodiments, the resistive element surface of the electromechanical conversion unit may be plated with a ceramic insulating layer with a thickness of 0.2 mm, and the sliding contact pressure is set to 0.6 ± 0.1 N.

[0034] In some embodiments, the gear set can be configured as a helical tooth structure with a helix angle of 15°, and the phase angle error of the rack can be controlled within ±3'.

[0035] In some embodiments, the tail of the main body 2 is integrated with a signal processing module, which collects the resistance value change in real time and outputs a 4-20mA standard signal.

Claims

1. A displacement amplification mechanism for improving the resolution and measurement accuracy of a displacement sensor, comprising a main body (2), a slide rod (5), and an electromechanical conversion unit, wherein the electromechanical conversion unit comprises a fixed part (4) and a sliding part (3), which are slidably engaged, characterized in that: The main body (2) is a long strip shell. The electromechanical conversion unit is set inside the main body (2). The fixing part (4) in the electromechanical conversion unit is fixedly connected to the inside of the main body (2). The slide rod (5) has one end slidably inserted into the main body (2) and fixedly connected to the sliding part (3) in the electromechanical conversion unit. The other end extends out from the end of the main body (2), and a first toothed rack (10) is machined on the outside of the extended end. Gear frame (6), the gear frame (6) is installed at the end of the main body (2), and a gear set is installed on the end of the gear frame (6) away from the main body (2). Each gear set includes a large gear (9) and a small gear (8), and the large gear (9) and the small gear (8) are installed on the same rotating shaft. The sliding sleeve (7) is fitted on the outside of the gear frame (6) and slides in contact with the outer wall of the gear frame (6). A second rack (11) is fixedly provided on the inner wall of the sliding sleeve (7). The large gear (9) and small gear (8) in the gear set mesh with the first rack (10) and the second rack (11), respectively.

2. The displacement amplification mechanism for improving the resolution and measurement accuracy of a displacement sensor according to claim 1, characterized in that: The gear frame (6) is inserted from the end of the main body (2) and can be locked and fixed by the first bolt (12). At the same time, the side of the sliding sleeve (7) is equipped with a second bolt (13), and the sliding sleeve (7) can be fixed on the gear frame (6) by the second bolt (13).

3. The displacement amplification mechanism for improving the resolution and measurement accuracy of a displacement sensor according to claim 1, characterized in that: In the electromechanical conversion unit, the fixed part (4) is a resistor and the sliding part (3) is a sliding contact. The resistor and the sliding contact are respectively connected to the external circuit through the cable (1). When the slide rod (5) slides relative to the main body (2), the sliding contact slides along the resistor, causing the resistance value of the connected circuit to change accordingly, thereby converting the mechanical signal into an electrical signal.

4. The displacement amplification mechanism for improving the resolution and measurement accuracy of a displacement sensor according to claim 1, characterized in that: There are two sets of gear sets, which are symmetrically arranged on both sides of the slide bar (5).

5. A displacement amplification mechanism for improving the resolution and measurement accuracy of a displacement sensor according to claim 1, characterized in that: The outer diameter of the main body (2) and the sliding sleeve (7) are the same.

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