A machine tool linear rolling guide and a linear rolling guide oil film repair method

Abstract

The invention discloses a linear rolling guide oil film repair method, which is applied to the linear rolling guide of a machine tool, and comprises the following steps: moving a slider forward: the oil film repair program first controls the slider to move forward along the guide rail, and the moving distance is greater than twice the length of the slider; moving the slider backward: the oil film repair program then controls the slider to move the same distance in the reverse direction along the guide rail back to the starting point; strengthening the supply of lubricating oil: while a numerical control system controls a centralized lubrication system to automatically inject lubricating oil into the slider in a timely and quantitative manner, the oil film repair program controls the centralized lubrication system to strengthen the forced supply of lubricating oil, and the oil film between the ball and the raceway is restored by the above method, so as to avoid the increase of friction and wear between the ball and the raceway caused by the destruction of the oil film, which greatly reduces the stability and reliability of the machine tool, and the performances such as temperature rise, noise and vibration are obviously deteriorated, thereby affecting the machining accuracy and machining quality of the numerical control machine tool. The invention also relates to a linear rolling guide of a machine tool.

Description

Technical Field

[0001] The invention relates to a guide rail, in particular to a linear rolling guide rail for a machine tool. Background Art

[0002] With the continuous development of modern manufacturing technology, CNC technology, mechatronics and industrial robots are more widely used in production. The positioning, guiding accuracy, cutting speed and rapid feed of mechanical transmission mechanisms are constantly improving, making linear rolling guides replace the previously widely used sliding linear guides, centralized lubrication systems replace manual oil supply, and linear rolling guides can achieve high-precision linear motion under high load conditions.

[0003] When the coordinate axis of the machine tool is continuously micro-fed for a long time, the lubricating oil is easy to leak under low-speed operation, and a good oil film is not formed between the ball and the raceway. It is in the boundary lubrication area, the friction factor becomes larger, and the friction force is larger. In addition, the lubrication effect of the ball and the raceway in some areas far away from the lubricating oil nozzle is not good, the oil film is gradually destroyed, and the friction and wear between the ball and the raceway in the linear guide pair increase. At this time, the working stability and reliability of the machine tool are greatly reduced, and the temperature rise, noise, vibration and other performances are significantly deteriorated, thereby affecting the processing accuracy and processing quality of the CNC machine tool.

[0004] When the lubrication condition is poor for a long time, the friction and wear of the linear rolling guide will increase, and the temperature inside the slider will rise abnormally, which will eventually lead to failure of the linear rolling guide. Common faults and failure modes include fatigue pitting of the guide raceway, slider sticking, rupture or burning of the slider return device, fatigue pitting of the slider raceway, flying of the rolling elements, crushing of the rolling elements, etc. Summary of the invention

[0005] In order to overcome the shortcomings of the prior art, one of the objects of the present invention is to provide a machine tool linear rolling guide rail whose oil film can be repaired, so as to avoid the increase of friction and wear caused by the destruction of the oil film between the ball and the raceway, which leads to a significant reduction in the stability and reliability of the machine tool, and a significant deterioration in the temperature rise, noise, vibration and other performance, thereby avoiding affecting the processing accuracy and processing quality of the CNC machine tool.

[0006] In order to overcome the shortcomings of the prior art, the second purpose of the present invention is to provide a method for repairing the oil film of a linear rolling guide, so as to avoid the increase in friction and wear caused by the destruction of the oil film between the ball and the raceway, which leads to a significant reduction in the stability and reliability of the machine tool, and a significant deterioration in the temperature rise, noise, vibration and other performance, thereby avoiding affecting the processing accuracy and processing quality of the CNC machine tool.

[0007] One of the purposes of the present invention is achieved by the following technical solution:

[0008] A machine tool linear rolling guide, comprising a guide rail and a slider slidably mounted on the guide rail, a raceway being formed between the guide rail and the slider, the machine tool linear rolling guide also comprising balls, internal sealing gaskets, end face sealing gaskets and bottom face sealing gaskets, the balls being accommodated in the raceway, the internal sealing gasket being located between the guide rail and the slider, the end face sealing gasket being located at the end of the slider, the bottom face sealing gasket being located at the bottom contacting position between the slider and the guide rail, the internal sealing gasket, the end face sealing gasket and the bottom face sealing gasket sealing the raceway to prevent leakage of lubricating oil in the raceway.

[0009] Furthermore, the machine tool linear rolling guide rail also includes an oil nozzle, and the oil nozzle is connected to the raceway to supply oil to the raceway.

[0010] Furthermore, the machine tool linear rolling guide rail also includes a retaining frame, and the retaining frame is installed between the guide rail and the slider.

[0011] Furthermore, the machine tool linear rolling guide rail also includes a reverser, and the reverser is installed at the end of the slider.

[0012] The second object of the present invention is achieved by adopting the following technical solution:

[0013] A linear rolling guide oil film repair method, applied to the above-mentioned machine tool linear rolling guide, comprises the following steps:

[0014] Move the slider forward: The oil film repair program first controls the slider to move forward along the guide rail, and the moving distance is greater than 2 times the slider length;

[0015] Move the slider in the opposite direction: the oil film repair program controls the slider to move the same distance in the opposite direction along the guide rail and return to the starting point;

[0016] Strengthen the lubricating oil supply: the CNC system controls the centralized lubrication system to automatically inject lubricating oil into the slider at a fixed time and quantity, while the oil film repair program controls the centralized lubrication system to strengthen the forced supply of lubricating oil.

[0017] Furthermore, the method also includes the following steps: when the coordinate axis of the machine tool is continuously micro-fed for a long time, an oil film repair program is inserted in the middle of the linear rolling guide micro-feed motion program.

[0018] Furthermore, the speed of the slider moving in the forward direction is equal to the speed of the slider moving in the reverse direction.

[0019] Further, when the rapid moving speed of the machine tool is less than or equal to 30 m / min, the moving speed of the slider is the rapid moving speed of the machine tool.

[0020] Furthermore, when the rapid moving speed of the machine tool is greater than 30 m / min, the moving speed of the slider is set to 30 m / min.

[0021] Furthermore, when the width of the guide rail is 15mm or 20mm, the lubricating oil supply rate is 0.2ml / h; when the width of the guide rail is 25mm, 30mm or 35mm, the lubricating oil supply rate is 0.3ml / h; when the width of the guide rail is 45mm, the lubricating oil supply rate is 0.4ml / h; when the width of the guide rail is 55mm, the lubricating oil supply rate is 0.5ml / h; when the width of the guide rail is 65mm, the lubricating oil supply rate is 0.6ml / h.

[0022] Compared with the prior art, in the linear rolling guide oil film repair method of the present invention, when the oil film between the ball and the raceway is destroyed, the oil film between the ball and the raceway is restored by moving the slider forward, moving the slider backward and increasing the supply of lubricating oil, thereby avoiding the increase of friction and wear between the ball and the raceway due to the destruction of the oil film, which greatly reduces the stability and reliability of the machine tool, and significantly deteriorates the performance such as temperature rise, noise and vibration, thereby avoiding affecting the processing accuracy and processing quality of the CNC machine tool. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a structural schematic diagram of the linear rolling guide of the machine tool of the present invention;

[0024] Figure 2 The present invention is a flow chart of the linear rolling guide rail oil film repair method.

[0025] In the figure: 1. internal sealing gasket; 2. slider; 3. reverser; 4. end sealing gasket; 5. grease nozzle; 6. bottom sealing gasket; 7. retaining frame; 8. ball; 9. guide rail. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] It should be noted that when a component is referred to as being "fixed to" another component, it may be directly on the other component or there may be another intermediate component through which it is fixed. When a component is considered to be "connected to" another component, it may be directly connected to the other component or there may be another intermediate component at the same time. When a component is considered to be "set on" another component, it may be directly set on the other component or there may be another intermediate component at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only.

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0029] See also Figure 1 The present invention discloses a linear rolling guide rail for a machine tool, comprising an internal sealing gasket 1, a slider 2, a deflector 3, an end sealing gasket 4, an oil nozzle 5, a bottom sealing gasket 6, a retaining frame 7, a ball 8 and a guide rail 9.

[0030] The slider 2 is installed on the guide rail 9. A raceway is formed between the slider 2 and the guide rail 9, and the ball 8 is located in the raceway. The oil nozzle 5 is connected to the raceway to add lubricating oil to the raceway. The deflector 3 is installed at the end of the slider 2. The deflector 3 is provided with a raceway and is connected to the raceway formed between the slider 2 and the guide rail 9 so that the raceway forms a circulation passage. The internal sealing gasket 1 is located between the upper part of the guide rail 9 and the inside of the slider 2, and the end face sealing gasket 4 is located at the end of the slider 2 and fits with the deflector 3. The bottom sealing gasket 6 is located between the bottom of the side of the slider 2 and the side of the guide rail 9. The retaining frame 7 is installed on the bottom sealing gasket 6 and contacts the slider 2. The internal sealing gasket 1, the end face sealing gasket 4 and the bottom sealing gasket 6 keep the raceway sealed.

[0031] Normally, the motion state of the linear rolling guide pair is that the guide rail 9 is stationary and the slider 2 moves linearly. The ball 8 rotates around its own axis and rolls around the raceway at the same time. When the ball 8 moves in the load-bearing area, it is not a simple pure rolling, but a combination of various spatial movements, including the sliding motion of the ball 8, the gyroscopic motion of the ball 8, and the spin motion of the ball 8. Sliding motion of the ball 8: In addition to rolling and rotating along the movement direction of the slider 2, the ball 8 in the load-bearing area will also slide around the normal direction of the contact surface. The sliding of the ball 8 will increase the contact load of the ball 8, causing the friction characteristics of the linear rolling guide pair to change. Gyroscopic motion of the ball 8: Since the contact angle of the linear rolling guide is not zero, the direction of the rotation axis of the ball 8 is constantly changing, so it is affected by the gyroscopic torque and produces gyroscopic motion. Gyroscopic motion can cause sliding friction between the ball 8 and the raceway, increase friction loss, and gyroscopic motion should be suppressed or avoided. Spinning motion of ball 8: The motion of ball 8 in the linear rolling guide pair is three-dimensional. If the contact angle is not zero, ball 8 will spin around the normal of the contact point. Spinning motion has a very important influence on the formation of the elastic flow lubricating oil film in the guide pair and the magnitude of the friction force.

[0032] When the coordinate axis of the machine tool is continuously micro-fed for a long time, the slider 2 of the linear rolling guide runs at a low speed for a long time, and the reciprocating distance is less than or equal to 1 / 2 of the length of the slider 2. When running at a low speed, the lubricating oil is easy to leak, and a good oil film is not formed between the ball 8 and the raceway. It is in the boundary lubrication area, the friction coefficient becomes larger, and the friction force is larger. In addition, the lubrication effect of the ball 8 and the raceway in the partial area far away from the oil nozzle 5 is not good, the oil film is gradually destroyed, and the friction between the ball 8 and the raceway in the linear guide pair increases, and the wear increases. At this time, the working stability and reliability of the machine tool are greatly reduced, and the performance such as temperature rise, noise, and vibration deteriorate significantly, thereby affecting the processing accuracy and processing quality of the CNC machine tool.

[0033] When the lubrication condition is poor for a long time, the friction and wear of the linear rolling guide will be aggravated, and the temperature inside the slider 2 will rise abnormally, which will eventually lead to failure of the linear rolling guide. Common faults and failure modes include fatigue pitting of the raceway surface of the guide rail 9, jamming of the slider 2, rupture or burning of the return device 3, fatigue pitting of the raceway surface of the slider 2, flying of the ball 8, crushing of the ball 8, etc.

[0034] Therefore, when the oil film needs to be repaired, the three conditions for forming a dynamic pressure lubricating oil film must be considered:

[0035] (1) There is a relative motion speed between the two surfaces; (2) There is a converging wedge-shaped gap between the two friction surfaces, and the lubricating oil enters from the large opening and flows out from the small opening; (3) The lubricating oil between the two surfaces has a certain viscosity, and the oil supply must be sufficient.

[0036] In order to ensure sufficient oil supply, the lubricating oil supply rate is formed into the following table according to the different specifications and models of the linear rolling guide.

[0037] Linear rolling guide pair oil supply rate table

[0038] Specifications (mm) Lubricating oil supply rate (ml / h) 15 0.2 20 0.2 25 0.3 30 0.3 35 0.3 45 0.4 55 0.5 65 0.6

[0039] Please continue reading Figure 2 The present application also relates to a linear rolling guide rail oil film repair method, which is applied to the above-mentioned machine tool linear rolling guide rail, comprising the following steps:

[0040] Move the slider 2 forward: The oil film repair program first controls the slider 2 to move forward along the guide rail 9, and the moving distance is greater than 2 times the length of the slider 2;

[0041] Move the slider 2 in the reverse direction: the oil film repair program controls the slider 2 to move the same distance in the reverse direction along the guide rail 9 to return to the starting point;

[0042] Strengthen the lubricating oil supply: the CNC system controls the centralized lubrication system to automatically inject lubricating oil into the slider 2 at a fixed time and in a fixed quantity, while the oil film repair program controls the centralized lubrication system to strengthen the forced supply of lubricating oil.

[0043] Before the step of moving the slider 2 forward, the step also includes: when the coordinate axis of the machine tool continuously micro-feeds for a long time, inserting an oil film repair program in the middle of the linear rolling guide micro-feed motion program. The speed of the slider 2 moving forward is equal to the speed of the reverse movement. When the machine tool fast moving speed is less than or equal to 30m / min, the moving speed of the slider 2 is the fast moving speed of the machine tool. When the machine tool fast moving speed is greater than 30m / min, the moving speed of the slider 2 is set to 30m / min.

[0044] Through the above method, the oil film between the ball 8 and the raceway is restored, avoiding the increase of friction and wear between the ball 8 and the raceway due to the destruction of the oil film, greatly reducing the stability and reliability of the machine tool, and significantly deteriorating the performance such as temperature rise, noise, and vibration, thereby avoiding affecting the processing accuracy and processing quality of the CNC machine tool.

[0045] For those skilled in the art, various other corresponding changes and deformations can be made according to the technical solutions and concepts described above, and all of these changes and deformations should fall within the protection scope of the claims of the present invention.

Claims

1. A linear rolling guide oil film repair method, characterized in that: The machine tool linear rolling guide comprises a guide rail and a slider slidably mounted on the guide rail, a raceway is formed between the guide rail and the slider, the machine tool linear rolling guide also comprises balls, internal sealing gaskets, end face sealing gaskets and bottom face sealing gaskets, the balls are accommodated in the raceway, the internal sealing gaskets are located between the guide rail and the slider, the end face sealing gaskets are located at the end of the slider, the bottom face sealing gaskets are located at the bottom contacting position between the slider and the guide rail, the internal sealing gaskets, the end face sealing gaskets and the bottom face sealing gaskets seal the raceway to prevent the lubricating oil in the raceway from leaking, During the repair process: Move the slider forward: the oil film repair program first controls the slider to move forward along the guide rail, and the moving distance is greater than 2 times the length of the slider; Move the slider backward: the oil film repair program then controls the slider to move the same distance in the opposite direction along the guide rail back to the starting point; Strengthen the supply of lubricating oil: the CNC system controls the centralized lubrication system to automatically inject lubricating oil into the slider at a fixed time and quantity, while the oil film repair program controls the centralized lubrication system to strengthen the forced supply of lubricating oil: when the width of the guide rail is 15mm or 20mm, the lubricating oil supply rate is 0.2ml / h; when the width of the guide rail is 25mm, 30mm or 35mm, the lubricating oil supply rate is 0.3ml / h; when the width of the guide rail is 45mm, the lubricating oil supply rate is 0.4ml / h; when the width of the guide rail is 55mm, the lubricating oil supply rate is 0.5ml / h; when the width of the guide rail is 65mm, the lubricating oil supply rate is 0.6ml / h.

2. The linear rolling guide rail oil film repair method according to claim 1, characterized in that: The following steps are also included: When the coordinate axis of the machine tool is continuously micro-fed for a long time, the oil film repair program is inserted in the middle of the linear rolling guide micro-feed motion program.

3. The linear rolling guide rail oil film repair method according to claim 2, characterized in that: The speed of the slider moving in the forward direction is equal to the speed of the slider moving in the reverse direction.

4. The linear rolling guide rail oil film repair method according to claim 3, characterized in that: When the rapid moving speed of the machine tool is less than or equal to 30m / min, the moving speed of the slider is the rapid moving speed of the machine tool.

5. The linear rolling guide rail oil film repair method according to claim 4, characterized in that: When the rapid moving speed of the machine tool is greater than 30 m / min, the moving speed of the slide is set to 30 m / min.

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