Hydraulic cylinder based on automatic ranging of novel structure

Abstract

This utility model discloses a hydraulic cylinder for automatic distance measurement based on a novel structure. It includes an outer cylinder and an inner cylinder, which are mechanically connected by an end cap flange. A piston rod is disposed inside the inner cylinder, and a distance measurement module is fixedly connected to the bottom end of the inner cylinder. The high-resolution laser module contains a laser distance sensor, a self-calibration module, and a signal processing unit. The laser distance sensor performs non-contact measurement with the piston rod. The self-calibration module incorporates a temperature compensation algorithm to dynamically correct the encoder output based on the oil temperature. The signal processing unit converts the laser signal into absolute position data and outputs it via a bus. Through this structure, by establishing the outer cylinder, inner cylinder, and distance measurement module, the piston rod position can be automatically measured. It features a simple structure, convenient maintenance, high measurement accuracy, and low cost.

Description

Technical Field

[0001] This utility model relates to the field of hydraulic system control technology, specifically to a hydraulic cylinder with a novel structure for automatic distance measurement. Background Technology

[0002] Traditional hydraulic cylinder position measurement methods often employ mechanical limit switches, magnetostrictive sensors, or LVDTs (linear variable differential transformers), which suffer from low accuracy (e.g., ±1mm), poor environmental adaptability (e.g., affected by oil contamination / vibration), high cost, or complex installation. Traditional hydraulic cylinder position measurement also includes indirect methods (e.g., calculating displacement through flow integration), which are susceptible to oil leakage and pressure fluctuations, resulting in large cumulative errors. Furthermore, traditional hydraulic cylinder sensor integration schemes present a maintenance dilemma: protecting the sensor from oil contamination (e.g., adding a sealing cover) makes sensor replacement difficult; prioritizing ease of maintenance (e.g., external sensors) makes it difficult to avoid oil contamination affecting measurement accuracy. This design contradiction leads to persistently high maintenance costs.

[0003] To address the aforementioned issues, we provide a hydraulic cylinder with an automatic distance measurement system based on a novel structure. Utility Model Content

[0004] This utility model provides a hydraulic cylinder based on a novel structure for automatic distance measurement. It can automatically measure the position of the piston rod by setting up an outer cylinder, an inner cylinder, and a distance measurement module. It has the characteristics of simple structure, convenient maintenance and low cost.

[0005] To achieve the above objectives, a hydraulic cylinder based on a novel structure for automatic distance measurement is provided, comprising an outer cylinder and an inner cylinder, which are mechanically connected by an end cap flange. A piston rod is disposed inside the inner cylinder, and a distance measurement module is fixedly connected to the bottom end of the inner cylinder. The high-resolution laser module contains a laser distance sensor, a self-calibration module, and a signal processing unit. The laser distance sensor performs non-contact measurement with the piston rod. The self-calibration module has a built-in temperature compensation algorithm that dynamically corrects the encoder output based on the oil temperature. The signal processing unit converts the laser signal into absolute position data and outputs it via a bus.

[0006] According to the hydraulic cylinder based on a novel structure for automatic distance measurement, the laser distance sensor is used to output displacement pulse signals in real time, and the two ends of the inner cylinder are sealed with sapphire glass to form transparent windows.

[0007] According to the hydraulic cylinder for automatic distance measurement based on a novel structure, the windows on both ends of the inner cylinder allow laser light from a laser distance measuring sensor to pass through.

[0008] According to the hydraulic cylinder based on a novel structure for automatic distance measurement, the inner cylinder is in a sealed inert gas environment.

[0009] According to the hydraulic cylinder based on a novel structure for automatic ranging, a desiccant is placed inside the inner cylinder. The desiccant can prevent oil vapor from adhering to the window, thereby improving the stability of laser ranging (measured fluctuation < ±0.01mm).

[0010] According to the aforementioned hydraulic cylinder for automatic distance measurement based on a novel structure, the outer cylinder is connected to an external hydraulic system.

[0011] According to the hydraulic cylinder for automatic distance measurement based on a novel structure, the clearance between the piston rod and the inner cylinder is ≤0.05mm, which reduces the interference of mechanical vibration on laser measurement.

[0012] The beneficial effects of this utility model are as follows: the double-layer cylindrical structure and the independent sealing design of the inner cylinder completely isolate the ranging module from the hydraulic oil, making its maintenance simple and convenient. The ranging module adopts the laser ranging method, which has high accuracy and is easy to use, thus solving the long-standing contradiction between maintainability, accuracy and ease of use, and at a lower cost.

[0013] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0014] The present invention will be further described below with reference to the accompanying drawings and embodiments;

[0015] Figure 1 This is a schematic diagram of the overall structure of a hydraulic cylinder for automatic distance measurement based on a novel structure, according to this utility model.

[0016] Figure 2 This is a schematic diagram of the internal structure of a hydraulic cylinder for automatic distance measurement based on a novel structure, according to this utility model. Figure 1 ;

[0017] Figure 3 This is a schematic diagram of the internal structure of a hydraulic cylinder for automatic distance measurement based on a novel structure, according to this utility model.

[0018] Figure 4 This is a schematic diagram of the laser optical path of a hydraulic cylinder for automatic distance measurement based on a novel structure, according to this utility model.

[0019] Legend:

[0020] 1. Outer cylinder; 2. Inner cylinder; 3. Distance measuring module; 4. Piston rod; 5. Laser optical path. Detailed Implementation

[0021] This section will describe in detail the specific embodiments of the present utility model. The preferred embodiments of the present utility model are shown in the accompanying drawings. The purpose of the drawings is to supplement the textual description with graphics, so that people can intuitively and vividly understand each technical feature and the overall technical solution of the present utility model, but they should not be construed as limiting the scope of protection of the present utility model.

[0022] Reference Figures 1 to 4 This utility model discloses a hydraulic cylinder for automatic distance measurement based on a novel structure, comprising an outer cylinder 1 and an inner cylinder 2, which are mechanically connected by an end cap flange. A piston rod 4 is installed inside the inner cylinder 2, and a distance measuring module 3 is fixedly connected to the bottom of the inner cylinder 2. The distance measuring module 3 contains a laser distance sensor, a self-calibration module, and a signal processing unit. The laser distance sensor and the piston rod 4 are non-contact measurement devices. The self-calibration module has a built-in temperature compensation algorithm that dynamically corrects the encoder output based on the oil temperature. The signal processing unit converts the laser signal into absolute position data and outputs it through a bus. The signal processing unit uses an STM32H743 chip.

[0023] The inner cylinder 2 contains a desiccant and is a sealed inert gas environment. The clearance between the piston rod 4 and the inner cylinder 2 is ≤0.05mm. The independent sealing design of the inner cylinder 2 completely isolates the ranging module 3 from the hydraulic oil, eliminating the need to drain the hydraulic oil during maintenance (saving 90% of maintenance time compared to traditional solutions).

[0024] The laser rangefinder sensor is used to output displacement pulse signals in real time. The two ends of the inner cylinder 2 are sealed with sapphire glass to form transparent windows. The outer cylinder 1 is connected to the external hydraulic system. The windows on both ends of the inner cylinder 2 allow the laser of the laser rangefinder sensor to pass through. Specifically, compared with the traditional magnetic grid solution, this solution does not require draining oil when replacing the sensor, reducing the maintenance cost within five years from 12,000 yuan to 3,500 yuan, and significantly shortening the system downtime caused by each maintenance from eight hours to two hours.

[0025] Working principle: The laser rangefinder in the ranging module 3 emits a laser beam towards the bottom of the piston rod 4. The laser beam passes through the sapphire glass window on the end face of the inner cylinder 2, is reflected by the bottom of the piston rod 4, and returns along the original path to the laser rangefinder. The time difference between the laser rangefinder and the bottom of the piston rod 4 is used to calculate the absolute distance between the laser rangefinder and the bottom of the piston rod 4. This distance data is converted into the real-time displacement of the piston rod 4 by the signal processing unit. At the same time, the self-calibration module monitors the ambient temperature through a built-in temperature sensor and uses a temperature compensation algorithm to dynamically correct the measurement results. Finally, high-precision, temperature-compensated absolute position data is output through the bus.

[0026] The embodiments of the present utility model have been described in detail above with reference to the accompanying drawings. However, the present utility model is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present utility model.

Claims

1. A hydraulic cylinder for automatic distance measurement based on a novel structure, characterized in that, The device includes an outer cylinder (1) and an inner cylinder (2), which are mechanically connected by an end cap flange. A piston rod (4) is installed inside the inner cylinder (2), and a ranging module (3) is fixedly connected to the bottom of the inner cylinder (2). The ranging module (3) is equipped with a laser ranging sensor, a self-calibration module, and a signal processing unit. The laser ranging sensor and the piston rod (4) are non-contact measurements. The self-calibration module has a built-in temperature compensation algorithm that dynamically corrects the encoder output according to the oil temperature. The signal processing unit converts the laser signal into absolute position data and outputs it through a bus.

2. The hydraulic cylinder for automatic distance measurement based on a novel structure according to claim 1, characterized in that, The laser rangefinder is used to output displacement pulse signals in real time, and the two ends of the inner cylinder (2) are sealed with sapphire glass to form transparent windows.

3. A hydraulic cylinder for automatic distance measurement based on a novel structure according to claim 2, characterized in that, The windows on both ends of the inner cylinder (2) allow the laser from the laser rangefinder to pass through.

4. A hydraulic cylinder for automatic distance measurement based on a novel structure according to claim 2, characterized in that, The inner cylinder (2) is enclosed in a sealed inert gas environment.

5. A hydraulic cylinder for automatic distance measurement based on a novel structure according to claim 2, characterized in that, A desiccant is placed inside the inner cylinder (2).

6. A hydraulic cylinder for automatic distance measurement based on a novel structure according to claim 1, characterized in that, The outer cylinder (1) is connected to an external hydraulic system.

7. A hydraulic cylinder for automatic distance measurement based on a novel structure according to claim 1, characterized in that, The clearance between the piston rod (4) and the inner cylinder (2) is ≤0.05mm.

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