CN112361946A

CN112361946A - High-precision automatic length measuring device

Info

Publication number: CN112361946A
Application number: CN202011291522.3A
Authority: CN
Inventors: 赵海潇; 曹融融
Original assignee: Kunming Wuwei S&t Industry Trade Co ltd
Current assignee: Kunming Wuwei S&t Industry Trade Co ltd
Priority date: 2020-11-18
Filing date: 2020-11-18
Publication date: 2021-02-12

Abstract

The invention discloses an automatic device capable of realizing high-precision length measurement. When the device is used for measuring the length of a workpiece, the workpiece to be measured is firstly hoisted or manually placed on a measuring platform, the distance between counting zero points at two ends of the platform is known, the guiding rule starts from two ends of the platform, moves towards each other in time, starts counting when passing through the zero points at the two ends, and when the guiding rule is in contact with the front end/tail section of the workpiece, the length value of the workpiece can be read through the operation control console. The device can realize the rapid measurement of the length of a workpiece smaller than 1500mm, the measurement error is smaller than 0.01mm, the repetition precision is smaller than 0.01mm, the operation and measurement time is shorter than 1min, the manual intervention is not needed in the measurement process, and the full-automatic measurement is realized. The device structure in the invention has good expansibility, and the high-precision length measurement with larger size can be realized by using the structure which is the same as or similar to the device.

Description

High-precision automatic length measuring device

Technical Field

The invention relates to a high-precision automatic length measuring device, and belongs to the technical field of automatic measurement.

Background

The length measurement is a necessary detection index when a product is processed, assembled or delivered from a factory, and particularly, a large-sized long-strip-shaped workpiece and a product, such as an underwater vehicle, an aviation product or an aerospace product, have extremely high tolerance requirements on the length after assembly. However, in the actual measurement process, the problems of difficult hoisting and operation, low repeatability of the measurement result, large deviation, limited available high-precision measurement means and the like caused by human subjective factors in the measurement process exist.

Disclosure of Invention

In order to solve the problems, the invention provides a high-precision automatic length measuring device, which does not need manual intervention in the measuring process, avoids errors caused by manual operation, has good expansibility in structure, can realize length measurement from a small-sized strip object within 1 meter to dozens of meters or even dozens of meters, and has the characteristics of high precision of measuring results, good repeatability, convenience, high efficiency and the like.

In the device, a magnetic grating ruler and a high-precision linear displacement sensor are selected as measuring devices. The measuring error of the magnetic grid ruler can reach +/-5 mu m/m, the measuring stroke can be infinitely prolonged, the measuring range of the selected high-precision linear displacement sensor is 20mm, and the measuring precision error is +/-0.005 mm. The length measurement error of the device mainly comes from the accumulated error of the length of the magnetic grid ruler caused by the length of the workpiece.

The technical scheme of the invention is realized as follows:

a high-precision automatic length measuring device comprises a measuring platform, guiding rules at the left end and the right end, a workpiece support and an operation control console. When the device is used for measuring the length of a workpiece, an operation control console is started at first, the workpiece to be measured is hoisted or manually placed on a workpiece support, the guiding rule is controlled to start from the left end and the right end of a table board through the operation control console, counting is started after the zero point of system equipment, when the guiding rule is contacted with the front end/the tail end of the workpiece, the leaning surface of the guiding rule is tightly attached to the end surface of the workpiece, the guiding rule continues to move forwards under the driving of a motor, the leaning surface of the guiding rule moves backwards along a guide pillar and compresses a linear displacement sensor, when the operation control console detects the data output change of the linear displacement sensor, the motor is stopped immediately, and at the moment, the leaning surface is tightly attached to the front (rear) end surface of the workpiece under the action of a spring force on the guide. And finally, the data of the magnetic grid rulers on the two guiding rulers and the change numerical value of the linear displacement sensor are read, so that the length of the workpiece can be accurately calculated. After the measurement is finished, the guiding rule moves reversely and automatically returns to zero. The measurement principle is shown in fig. 1.

The high-precision automatic length measuring device comprises a measuring platform, guiding rules at the front end and the rear end, a workpiece support and an operation control console.

The measuring platform comprises a cast iron platform, a linear guide rail, a screw rod module, a magnetic grid ruler, a limit switch and a speed reduction driving motor, if a test workpiece is large and long, the cast iron platform can be replaced by a support welded by a section bar, and a ball screw pair can be replaced by a gear rack.

The guiding rule comprises a guiding rule bracket, a leaning surface, a guide pillar, a compression spring, a linear displacement sensor and a magnetic grid rule reading head.

Further, the zero positions of the guiding rulers at the left end and the right end of the device are determined by detecting zero signals which appear on the magnetic grid ruler at intervals of 20cm in a circulating manner, and the first zero signals detected inwards by the limit switch are set as zero points at the left end and the right end.

Furthermore, the distance between the zero points of the guiding rulers on the left side and the right side of the device can be obtained by adding measuring blocks with standard length measured by the guiding rulers or by calculating after controlling the left guiding ruler and the right guiding ruler to move in opposite directions and the guiding rulers to contact with each other.

Furthermore, the reading head of the magnetic grid ruler continuously reads the position data of the magnetic grid ruler in the running rule moving process. The linear displacement sensor is pre-compressed and installed at the rear end of the leaning surface, and after the leaning surface is in contact with a workpiece and stressed, the leaning surface can move backwards along the guide pillar, so that the linear displacement sensor is compressed, and a compression spring on the guide pillar can ensure that the leaning surface is pressed and tightly attached to the workpiece to be measured.

Further, the change value read by the linear displacement sensor is subtracted from the value read by the magnetic grid ruler, so that the position of the front/rear end surfaces of the workpiece to be measured in the system can be calculated. And the length of the workpiece to be measured can be calculated by combining the space between zero points at the left end and the right end of the system.

The operation console comprises a control box body, an industrial personal computer, a self-developed special control panel, a display and self-programmed measurement and control software.

Drawings

FIG. 1 is a schematic diagram of the measurement of the present invention;

FIG. 2 is a front view of the high precision automated length measuring device provided by the present invention;

FIG. 3 is a top view of the high precision automated length measuring device provided by the present invention;

FIG. 4 is a schematic view of a guiding rule structure provided by the present invention;

fig. 5 is a schematic view of the shape of the operation console provided by the present invention.

Detailed Description

The technical solution of the present invention is described in detail and completely with reference to the accompanying drawings, and obviously, the described embodiments are only a part of the embodiments of the present invention, not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the embodiment of the invention, the high-precision automatic length measuring device comprises a guiding rule (1) at the left end and the right end, a measuring platform (2), a workpiece support (3) and an operation console (16).

The guiding ruler (1) is installed on the linear guide rail (7), is driven by a nut of the screw rod module (5), and moves left and right along the linear guide rail (7). The screw rod module is arranged on the module seat (4) and is driven by the speed reducing motor (6).

Linear guide (7), magnetic grid chi magnetic stripe (8), lead screw module (5), gear motor (6), limit switch (9) and work support (3) all install on measuring platform (2).

The guiding rule (1) consists of a leaning surface (10), a guide pillar (13), a compression spring (12), a guiding rule seat (11), a magnetic grid rule reading head (15) and a linear displacement sensor (14), wherein the guide pillar (13), the linear displacement sensor (14) and the magnetic grid rule reading head (15) are all installed on the leaning rule seat (11), the leaning surface (10) is installed on the guide pillar (13) and can move back and forth along the guide pillar (13), and the leaning surface (10) is propped against the foremost end of the guide pillar (13) by the elastic force of the compression spring (12). When the linear displacement sensor is installed, a measuring head of the linear displacement sensor (14) is abutted against the rear end face of the abutting face (10), the installation position of the linear displacement sensor (14) is adjusted, the measuring head is guaranteed to be pre-compressed, and a nonlinear measurement area of the sensor is avoided.

When the length of a workpiece is measured, firstly, a system operation control console (16) needs to be started, the workpiece to be measured is hoisted or manually placed on a workpiece support (3) on a measuring platform (2), two sets of guiding rules (1) are controlled to start from two ends of a table surface and move in opposite directions through the operation control console (16), after a magnetic grid ruler reading head (15) on each guiding rule reads a first zero position signal on a magnetic strip (8) of each magnetic grid ruler, counting is started, when the guiding rules (1) are contacted with the front end/tail end of the workpiece, a leaning surface (10) of each guiding rule is tightly attached to the end surface of the workpiece, the guiding rules (1) continue to move forwards under the driving of a speed reducing motor (6), the leaning surface (10) of each guiding rule compresses a linear displacement sensor (14) backwards along the direction of a guide post (13), and when the operation control console (16) detects the data change of the linear displacement sensor (14), the speed reducing motor (6) is stopped, at this time, the abutment surface (10) is tightly fitted to the front (rear) end surface of the workpiece by the compression spring (12). Finally, the numerical values on the magnetic strips (8) of the magnetic grid rulers are read by the two magnetic grid ruler reading heads (15), and the length of the workpiece can be accurately calculated by integrating the change numerical values of the linear displacement sensor (14). After the measurement is finished, the guiding ruler (1) automatically moves in the reverse direction, and automatically stops after moving to the position of the limit switch (9).

Claims

1. A high-precision automatic length measuring device comprises a measuring platform, guiding rules at the left end and the right end, a workpiece support and an operation control console.

2. A high precision automated length measuring device according to claim 1, wherein said guiding rule is composed of a guiding surface, a guiding rule base, a compression spring, a guiding pillar, a magnetic grid rule reading head and a high precision linear displacement sensor, the guiding pillar, the linear displacement sensor and the magnetic grid rule reading head are mounted on the guiding rule base, and said guiding rule is a main component of the whole length measurement.

3. The high precision automatic length measuring device according to claim 1, characterized in that the guiding rule has a leaning surface mounted on the guide post, the guiding rule can move back and forth along the guide post, the leaning surface is pressed against the foremost end of the guide post by a compression spring, a linear displacement sensor is mounted at the rear end of the leaning surface, and a measuring head of the linear displacement sensor is pre-compressed during mounting to avoid a non-linear measuring area of the sensor.

4. The high-precision automatic length measuring device according to claim 1, wherein a speed reducing motor is mounted on the measuring platform, and the speed reducing motor can drive the guiding rule to move and stop.

5. The high-precision automatic length measuring device according to claim 1, wherein the guiding rule can automatically stop after contacting with an object, and the guiding rule can be tightly attached to the object to be measured, so that precise measurement is realized.

6. The high-precision automatic length measuring device according to claim 1, wherein after the leaning surface of the guiding rule contacts with the workpiece, the guiding rule continues to move forward under the driving of the motor, the leaning surface clings to the object and moves backwards along the guide post, meanwhile, a measuring head of the linear displacement sensor is compressed, after a system detects the value change of the linear displacement sensor, the motor is automatically stopped, the leaning surface is tightly clung to the object under the action of the spring, and at the moment, the value of the magnetic grid rule and the change value of the linear displacement sensor are read, so that the accurate position of the end surface of the object in the device can be calculated.