A roller screw track surface roughening treatment method based on CNC oscillation cutting

Abstract

The present invention relates to a machining method, specifically a roller screw track surface roughening treatment method based on numerical control oscillation cutting, the processing idea is to regard the screw spiral track surface as a plurality of randomly distributed spiral lines, and regard each spiral line as a series of randomly distributed spiral points; through the three random methods of random axial spacing of spiral lines, random axial spacing of spiral points, and random length size of spiral points, the continuous turning process of the spiral track surface is decomposed into a combination of random oscillation turning processes of a plurality of spiral lines and a plurality of spiral points on the spiral lines, that is, the roughening treatment of the screw spiral track surface is completed. The ball screw after the roughening treatment of the present invention can reduce the friction and wear of the ball screw pair and increase the product life.

Description

Technical Field

[0001] The invention relates to a mechanical processing method, in particular to a roller screw track surface roughening processing method based on numerically controlled oscillating cutting. Background Art

[0002] like Figure 1 As shown, the ball screw consists of a screw 1, a nut 2 with an integrated reverser 3, a steel ball 4, etc. Its main function is to convert rotational motion into linear motion or torque into axial repetitive force. It is the most commonly used transmission element in tool machinery and precision machinery. It has the characteristics of stable, accurate and efficient transmission. It is widely used in machine tools, robots, medical equipment, semiconductor manufacturing, microelectronics assembly and other fields. During operation, a tunnel-shaped ball raceway is formed between the spiral track surface of the screw and the inner track surface of the nut. The rotation of the screw drives the steel ball to roll in a circle in the track to transfer the load and realize the linear reciprocating motion of the nut. The spiral track surface of the screw and the steel ball, and the steel ball and the inner track surface of the nut contact to form a relative motion friction pair.

[0003] In industries such as machine tools, semiconductor manufacturing, and microelectronics assembly, screws are required to frequently reciprocate at high speeds. With high-frequency transmission, friction and friction heat are bound to be generated between the friction pairs, which in turn leads to wear of the screw spiral track surface, steel balls, and the inner track surface of the nut, ultimately destroying the accuracy, stability, and life of the screw.

[0004] In order to reduce the friction and wear between the friction pairs, the prior art is to open an oil filling hole at the relevant part of the nut, open a cavity connected to the oil filling hole inside the nut, open through holes distributed at equal distances on the inner wall at the bottom of the cavity to communicate with the steel ball, and use an oil gun to lubricate the steel ball inside the nut through the oil filling hole. However, because the spherical surface of the steel ball of the screw rod fits with the spiral track surface of the screw rod and the inner track surface of the nut, under the action of the axial load, the lubricating oil cannot enter the friction pair well or squeeze out from the track surface and the steel ball, resulting in dry friction between the steel ball, the screw rod and the nut, which not only aggravates the wear, but also causes waste due to oil dripping, and pollutes the environment to a certain extent. At the same time, the steel ball is spherical, the spiral track surface of the screw rod and the inner track surface of the nut are in the shape of an arc groove, and the contact form is surface contact, resulting in a large contact area between the steel ball, the screw rod and the nut, further aggravating the friction and wear of the screw pair.

[0005] In addition, the track surface of the nut, the reverser mounting surface and other essential surfaces are difficult to process internal structures, and also have the function of adjusting the screw preload. If a cavity and oil channel connected to the oil injection hole are opened inside the nut, the structural complexity of the nut body and the difficulty of design and processing will be increased. Summary of the invention

[0006] In view of the above-mentioned technical problems or one of the technical problems existing in the prior art, the present invention proposes a roller screw track surface roughening processing method based on CNC oscillation cutting, wherein the processing idea is to regard the screw spiral track surface as a composition of a number of spiral lines with randomly distributed spacing, and further regard each spiral line as a composition of a series of spiral points with randomly distributed spacing; wherein each spiral line has the same lead as the spiral track surface S , the distance between the first spiral line and the edge of the spiral track surface is about 0.1 mm; the axial spacing between each spiral line is random, and its variation range is 0.1~0.5 mm; the axial spacing between adjacent spiral points on each spiral line is random, and its variation range is 0.1~0.2 mm; the length size of each spiral point is random, and its variation range is 20~30 μm. Through the three random methods of random axial spacing of spiral lines, random axial spacing of spiral points, and random length size of spiral points, the continuous turning of the spiral track surface is decomposed into a combination of random oscillation turning of several spirals and several spiral points on the spiral line, and the processing of randomly distributed bionic microtextures on the spiral track surface can be completed.

[0007] The technical solution adopted specifically includes the following steps:

[0008] A roller screw track surface roughening treatment method based on CNC oscillating cutting, the CNC lathe is a horizontal CNC lathe, the turning tool is a hard-coated turning tool, the tool tip angle is 25°, the arc radius is 0.05 mm, and the control module in the CNC lathe grids the spiral track surface of the ball screw into a number of virtual spirals with randomly distributed spacings, each virtual spiral has the same lead as the spiral track surface, and each virtual spiral is composed of a number of virtual spiral points with random axial spacings; the roughening treatment includes the following steps:

[0009] Step 1: Perform ultrasonic cleaning on the ball screw after fine processing for more than two times to remove oil and other debris on the surface, especially on the track surface of the ball screw. After cleaning, dry it naturally in the air;

[0010] Step 2: Clamp the cleaned and dried screw rod on the CNC lathe through the chuck and the center, and ensure that the spatial posture of the screw rod's rotation axis is horizontal; the spindle of the CNC lathe drives the screw rod to rotate through the chuck;

[0011] Step 3, the control module in the CNC lathe controls the tool tip to be positioned to the empty tool position of the first virtual spiral point on the first virtual spiral, that is, the position leaving a radial feed gap of 1 mm, controls the tool to radially feed to the first virtual spiral point of the first virtual spiral and quickly retract, completes the turning of the first virtual spiral point of the first virtual spiral along with the rotation of the spindle, and forms a long strip micro-pit at the first virtual spiral point; when the tool tip returns to the empty tool position of the first virtual spiral point on the first virtual spiral, the tool tip is axially displaced to the empty tool position of the second virtual spiral point on the first virtual spiral, controls the tool to radially feed to the second virtual spiral point of the first virtual spiral and quickly retract, completes the turning of the second virtual spiral point on the first virtual spiral, and forms a long strip micro-pit at the second virtual spiral point; repeats the random oscillation turning of all virtual spiral points of the first virtual spiral, and forms a plurality of long strip micro-pits along the first virtual spiral;

[0012] Step 4: The control module in the CNC lathe controls the tool tip to return to the empty tool position of the first virtual spiral point on the first virtual spiral, and axially displace to the empty tool position of the first virtual spiral point on the second virtual spiral, and complete the random oscillation turning of all virtual spiral points of the second virtual spiral in accordance with the method of step 3, and form a plurality of long strip micro-pits along the second virtual spiral;

[0013] Step 5: The method of step 4 is consistent with that of step 4, completing the random oscillation turning of all virtual spiral points on all virtual spirals, that is, completing the roughening treatment of the screw spiral track surface.

[0014] Furthermore, the distance between the first virtual spiral and the edge of the spiral track surface is 0.1 mm; the axial spacing between adjacent virtual spirals is randomly selected in the range of 0.1~0.5 mm; the axial spacing between adjacent virtual spiral points is randomly selected in the range of 0.1~0.2 mm; and the length of each virtual spiral point is randomly selected in the range of 20~30 μm.

[0015] Furthermore, the width of the long strip micro-pit depends on the arc radius of the turning tool tip angle, and the length of the long strip micro-pit depends on the contact time between the turning tool tip and the screw rod, and the contact time between the turning tool tip and the screw rod is randomly selected in the range of 0.003~0.01 s.

[0016] Furthermore, steps 3-5 are repeated to perform a roughening treatment on the spiral track surface of the screw rod once or more than twice.

[0017] Furthermore, the ball screw includes a screw rod, a nut with an integrated reverser, a steel ball, and an oil supply cleaner fixed at one end or both ends of the nut, wherein the oil supply cleaner includes

[0018] The inner diameter of the central circular hole of the disk body is larger than the outer diameter of the screw rod, and a plurality of axial through holes are evenly arranged on the end surface. A plurality of axial screw holes are arranged on one end or both end surfaces of the nut corresponding to the plurality of axial through holes; a fastening screw passes through the axial through hole and is screwed with the axial screw hole to fix the oil supply cleaner on the nut; two stepped holes with a smaller inner hole and a larger outer hole are relatively arranged along the radial direction of the disk body, and the outer section of the larger hole of the stepped hole is a threaded section, and the axes of the two stepped holes are at a distance of half a pitch of the screw rod, and one of the stepped holes is an oil filling hole, and the other stepped hole is a cleaning hole;

[0019] 1 oil supply head, which is in the shape of a stepped frustum as a whole, including a large frustum that matches the large hole of the step hole and a small frustum that matches the small hole of the step hole, and a central oil passage is provided in the center along the axial direction;

[0020] 1 cleaning head, the rest of the structure is the same as the oil supply head, but without the central oil channel;

[0021] 2 sealing screws, screwed to the threaded sections of the two stepped holes respectively;

[0022] Two springs, one end of which abuts against the oil supply head or the cleaning head, and the other end abuts against the sealing screw.

[0023] Furthermore, the small round platforms of the oil supply head and the cleaning head extend out of the step hole of the disc body and abut against the spiral track surface of the screw rod.

[0024] Furthermore, the free ends of the small cones of the oil supply head and the cleaning head are hemispherical, and the diameters thereof are equal to the diameter of the steel ball.

[0025] Furthermore, the oil supply head is at the upper part of the disc body, and the cleaning head is at the lower part of the disc body.

[0026] Compared with the prior art, the ball screw after the roughening treatment of the present invention has long strip-shaped micro-pits on the spiral track surface of the screw rod, which can reduce the contact area between the screw rod and the steel ball, so that the lubricating oil can directly and evenly act on the friction pair, avoiding the pressure extrusion of the lubricating oil between the track surface and the steel ball, improving the oil catching, oil storage and self-lubricating performance of the ball screw pair, thereby reducing the friction and wear of the ball screw pair and increasing the product life. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a structural schematic diagram of an existing screw rod.

[0028] Figure 2 It is a structural schematic diagram and a partial enlarged diagram of the ball screw after the roughening treatment of the present invention.

[0029] Figure 3 It is a structural schematic diagram of a nut of the present invention.

[0030] Figure 4 It is a structural schematic diagram of the oil supply cleaner of the present invention.

[0031] Figure 5 A schematic structural diagram of the oil supply cleaner disc of the present invention.

[0032] Figure 6 A schematic cross-sectional view of the oil supply cleaner disc of the present invention.

[0033] Figure 7 A schematic structural diagram of the oil supply head, spring and sealing screw of the oil supply cleaner of the present invention.

[0034] Figure 8 A schematic structural diagram of a cleaning head, a spring and a sealing screw of an oil supply cleaner of the present invention. DETAILED DESCRIPTION

[0035] In the description of the present invention, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they cannot be understood as limitations on the present invention.

[0036] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0037] The following is a description of the implementation of the present invention by specific embodiments. People familiar with the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. Obviously, the described embodiments are 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.

[0038] A roller screw track surface roughening treatment method based on CNC oscillating cutting, the CNC lathe is a horizontal CNC lathe, the turning tool is a hard-coated turning tool, the tool tip angle is 25°, and the arc radius is 0.05 mm; the control module in the CNC lathe grids the spiral track surface of the ball screw into a number of virtual spirals with randomly distributed spacing, each virtual spiral has the same lead as the spiral track surface, and each virtual spiral is composed of a number of virtual spiral points with random axial spacing;

[0039] The roughening process includes the following steps:

[0040] Step 1: Perform ultrasonic cleaning on the ball screw after fine processing for more than two times to remove oil and other debris on the surface, especially on the track surface of the ball screw. After cleaning, dry it naturally in the air;

[0041] Step 2: Clamp the cleaned and dried screw rod on the CNC lathe through the chuck and the center, and ensure that the spatial posture of the screw rod's rotation axis is horizontal; the spindle of the CNC lathe drives the screw rod to rotate through the chuck;

[0042] Step 3, the control module in the CNC lathe controls the tool tip to be positioned to the empty tool position of the first virtual spiral point on the first virtual spiral, that is, the position leaving a radial feed gap of 1 mm, controls the tool to radially feed to the first virtual spiral point of the first virtual spiral and quickly retract, completes the turning of the first virtual spiral point of the first virtual spiral along with the rotation of the spindle, and forms a long strip micro-pit at the first virtual spiral point; when the tool tip returns to the empty tool position of the first virtual spiral point on the first virtual spiral, the tool tip is axially displaced to the empty tool position of the second virtual spiral point on the first virtual spiral, controls the tool to radially feed to the second virtual spiral point of the first virtual spiral and quickly retract, completes the turning of the second virtual spiral point on the first virtual spiral, and forms a long strip micro-pit at the second virtual spiral point; repeats the random oscillation turning of all virtual spiral points of the first virtual spiral, and forms a plurality of long strip micro-pits along the first virtual spiral;

[0043] Step 4: The control module in the CNC lathe controls the tool tip to return to the empty tool position of the first virtual spiral point on the first virtual spiral, and axially displace to the empty tool position of the first virtual spiral point on the second virtual spiral, and complete the random oscillation turning of all virtual spiral points of the second virtual spiral in accordance with the method of step 3, and form a plurality of long strip micro-pits along the second virtual spiral;

[0044] Step 5: The random oscillation turning of all virtual spiral points on all virtual spirals is completed in the same way as in step 4, that is, the roughening treatment of the screw spiral track surface is completed. Long strip micro-pits are the most common type of texture morphology. The use of micro-pits arranged in a certain regular or disordered manner can significantly improve the lubrication conditions, store the function of detached abrasive particles, and reduce the contact area, solving the problem of oil shortage.

[0045] This method performs subsequent random oscillation CNC turning of the spiral track surface of the ball screw after fine machining. The processing idea is to regard the spiral track surface of the ball screw as a composition of several spiral lines with randomly distributed spacing, and further regard each spiral line as a series of spiral points with randomly distributed spacing; each spiral line has the same lead as the spiral track surface S, the distance between the first spiral line and the edge of the spiral track surface is about 0.1 mm; the axial spacing between each spiral line is random, and its range is 0.1~0.5 mm; the axial spacing between adjacent spiral points on each spiral line is random, and its range is 0.1~0.2 mm; the length size of each spiral point is random, and its range is 20~30 μm. Through the three random methods of random axial spacing of spiral lines, random axial spacing of spiral points, and random length size of spiral points, the continuous turning process of the spiral track surface is decomposed into a combination of random oscillation turning processes of several spirals and several spiral points on the spirals, that is, the roughening treatment of the screw spiral track surface is completed.

[0046] During the processing, a sharp-angle hard-coated turning tool, such as the Kyocera XBMT13T304GFC turning tool, is used to ensure that the cutting edge does not interfere with the spiral track surface. Before processing, the tool tip is positioned relative to the starting point of the first thread, leaving a 1mm radial feed clearance.

[0047] Through the macro program module in the CNC lathe, the spindle speed is assigned with time as the system variable. n , Tool tip axial feed speed v , radial feed speed v’、 Contact time between tool tip and screw The macro variable logical relationship between them accurately matches the spindle speed n , Tool tip axial feed speed v、 The time interval of radial cutting of the tool tip between two adjacent screw points T+t The exact relationship between T+t By controlling the timing of radial feed of the tool tip and controlling the number of radial feeds N of the tool tip through the total length of the spiral track surface and the distance between the spiral lines, the random oscillation relative motion dimensional relationship between the tool tip and the spiral track surface can be controlled, thereby realizing random oscillation turning of a series of spiral points on each spiral line.

[0048] During the processing, the spindle drives the screw to rotate at a constant speed. n About 600r / min, the rotation cycle is T According to the logical relationship in the above macro program, after the spindle rotates one circle, the time interval of the radial feed of the tool tip is T+t hour( t is a random variable within a small range, and its range of variation is as follows). The tool tip radially feeds once, and then quickly retreats after the thread point is turned. The contact time between the tool tip and the screw is , is a random variable in a small range, with a variation range of 0.003~0.01s, and its radial feed and retract speed v’ Fast enough to allow the tool tip to smoothly advance and retract. The width of each thread point is determined by the tool tip arc radius. rand cutting depth δ The random length can be determined by the contact time between the tool tip and the screw. After the spindle rotates one circle again, the next thread point is processed. T , the radial feeding time interval of the tool tip between two adjacent screw points T+t , Lead S , you can accurately match the axis feed speed of the tool tip To ensure the density of random spiral points on each spiral line, t The random value range is Repeating this method can complete the random oscillation CNC turning of all the spiral points on the same spiral line.

[0049] Before machining the spiral points on the second spiral line, return the tool tip to the starting point of the previous spiral line, and randomly move the tool tip position in the axial range of 0.1~0.5mm to position the tool tip relative to the starting point of the second spiral line, leaving a 1mm radial feed gap. According to the above method, random oscillation CNC turning of all spiral points on the second spiral line can be performed.

[0050] Repeating this method can perform random oscillation CNC turning processing on all the spiral points on the subsequent spiral line, that is, completing the roughening treatment of the spiral track surface of the screw rod.

[0051] The programming idea of ​​macro program is:

[0052] (1) Setting macro variables

[0053] S: #101 = n (n is the basic spindle speed, in r / min)

[0054] X: #102 = a (a is the radial coordinate of the first thread point of the first thread, unit: mm)

[0055] Z: #103 = b (b is the axial coordinate of the first screw point of the first thread, unit: mm)

[0056] F: #104 = c (c is the total axial feed of the tool tip, unit: mm / r)

[0057] Xap: #105 = e (e is the single-side displacement of the tool tip radial feed, in mm)

[0058] Zap: #106 = f (f is the unilateral displacement of the tool tip in the axial direction, in mm)

[0059] #107 = 0 (set the number of feeds to 0)

[0060] #3001=1 (time system variable, unit: milliseconds)

[0061] (2) Assign the changing relationship between macro variables during the processing

[0062] #101 = n / [#3001 * 1000 * 60] (the relationship between the set speed and time min)

[0063] #107 = #107 + 1 (set the number of feeds, count increments by 1)

[0064] #101 = #101 + 1 (the speed increases by 1r / min for each feed)

[0065] #104 = #104 — 0.1 (the feed rate decreases by 0.1mm / r each time the tool is fed)

[0066] #106 = #105 * tan Ф (Set the helix angle and the displacement relationship between the X and Z axes)

[0067] (3) Set the logical operation relationship between variables

[0068] IF [ #3001 = #3001 + 500] THEN [#107 = #107 + 1] (For every 0.01 second increase in the set time, the feed rate increases once)

[0069] IF [#107 = #107 + 1] THEN [# 106 = #106 + 1] (set the axial movement to increase by 1 mm for each feed)

[0070] IF #102 GE m GOTO 1 (m is the thread bottom diameter, set the radial dimension, if it is greater than or equal to m, execute the logical relationship under the N1 line number)

[0071] N1 (set execution line number 1)

[0072] #103 = #103 + #106 (the coordinate increment relationship of each X-axis feed)

[0073] #102 = #102 + #105 (the coordinate increment relationship of each Z-axis feed)

[0074] END 1 (corresponding to the paragraph end code of N1)

[0075] IF #102 LE nGOTO 2 (m' is the thread top diameter, set the radial dimension, if it is less than or equal to m', execute the logical relationship under the N2 line number)

[0076] N2 (set execution line number 2)

[0077] #103 = #103 — #106 (the decreasing coordinate relationship of each X-axis feed)

[0078] #102 = #102 — #105 (the coordinate decreasing relationship of each Z-axis feed)

[0079] END 2 (corresponding to the paragraph end code of N2)

[0080] IF #101 GE p THEN #101 = n (p is the maximum speed. When the set speed is greater than or equal to p, it returns to the initial speed n)

[0081] IF F#104 LE q THEN #104 = c (q is the minimum feed rate. When the set speed is less than or equal to q, it returns to the initial feed rate c)

[0082] IF #106 GE 2700 THEN [#103 = 5, #102 = 50] (If the axial displacement is greater than or equal to the effective length of the thread, the tool returns to the starting point of the workpiece).

[0083] In another preferred embodiment, the distance between the first virtual spiral and the edge of the spiral track surface is 0.1 mm; the axial spacing between adjacent virtual spirals is randomly selected in the range of 0.1~0.5 mm; the axial spacing between adjacent virtual spiral points is randomly selected in the range of 0.1~0.2 mm; the length of each virtual spiral point is randomly selected in the range of 20~30 μm.

[0084] In another preferred embodiment, the width of the elongated micro-pit depends on the arc radius of the turning tool tip angle, and the length of the elongated micro-pit depends on the contact time between the turning tool tip and the screw rod, and the contact time between the turning tool tip and the screw rod is randomly selected in the range of 0.003~0.01s.

[0085] In another preferred embodiment, steps 3-5 are repeated to perform a second or more roughening treatment on the spiral track surface of the screw rod. The long strip micro-pits are superimposed and connected to form a capillary lubrication channel, which produces a capillary effect on the lubricating oil. The lubricating oil can infiltrate, crawl, and store in the capillary lubrication channel, further improving and enhancing the lubrication performance.

[0086] In another preferred embodiment, the ball screw further includes an oil supply cleaner 5 fixedly mounted at both ends of the nut 2. The oil supply cleaner specifically includes

[0087] The disk body 51 has a central circular hole 511 with an inner diameter larger than the outer diameter of the screw rod 1, and a plurality of axial through holes 512 are evenly arranged on the end surface. A plurality of axial screw holes 21 are arranged on one end or both end surfaces of the nut 2 corresponding to the plurality of axial through holes 512; a fastening screw passes through the axial through hole 512 and is screwed with the axial screw hole 21 to fix the oil supply cleaner 5 on the nut 2; two stepped holes 513 with a smaller inner hole and a larger outer hole are relatively arranged along the radial direction of the disk body 51, and the outer section of the larger hole of the stepped hole 513 is a threaded section, and the axes of the two stepped holes 513 are at a distance of half a pitch of the screw rod 1, wherein one of the stepped holes 513 is an oil filling hole, and the other stepped hole 513 is a cleaning hole;

[0088] An oil supply head 52, which is in the shape of a stepped truncated cone as a whole, including a large truncated cone that is clearance matched with the large hole of the stepped hole 513 and a small truncated cone that is clearance matched with the small hole of the stepped hole 513, and a central oil passage 521 is axially provided at the center;

[0089] 1 cleaning head 53, the rest of which is the same structure as the oil supply head 52, except that it does not have the central oil passage 521;

[0090] Two sealing screws 54 are screwed to the threaded sections of the two stepped holes 513 respectively;

[0091] The two springs 55 have one end in contact with the oil supply head 52 or the cleaning head 53 and the other end in contact with the sealing screw 54 .

[0092] In another preferred embodiment, the small round cones of the oil supply head 52 and the cleaning head 53 extend out of the step hole 513 of the disc body 51 and abut against the spiral track surface 11 of the screw rod 1;

[0093] In another preferred embodiment, the free ends of the small cones of the oil supply head 52 and the cleaning head 53 are hemispherical, and the diameters thereof are equal to the diameters of the steel balls.

[0094] In another preferred embodiment, the cleaning head is located at the lower part of the tray body, and the oil supply head is located at the upper part of the tray body.

[0095] The oil supply device and the cleaning device of the present embodiment are combined into one to form an oil supply cleaner 5, which is installed separately from the nut. The traditional nut with automatic oil supply function that is difficult to process is transformed into a kit composed of several parts with simple structure and convenient connection, which reduces the difficulty of integrated design and processing of the nut and improves the strength and load-bearing capacity of the nut.

[0096] The working end of the cleaning head is a hemispherical head. When working, it needs to be close to the spiral track surface of the screw. The pressure can be adjusted by the sealing screw to clean the screw during its rotation. When replacing the cleaning head, remove the sealing screw, take the cleaning head out of the downward cleaning hole and replace it with a new cleaning head. Impurities will automatically fall out of the cleaning hole.

[0097] The working end of the oil supply head is also a hemispherical head. When working, it needs to be close to the spiral track surface of the screw. The pressure can be adjusted by the sealing screw, and the screw can be lubricated during its rotation. Unscrew the sealing screw, inject the lubricating oil, and the lubricating oil will seep through the central oil channel and lubricate the spiral track surface of the screw through the oil supply head. The capillary lubrication channel formed by the superposition and connection of micro-pits can fully capture and store the lubricating oil, and can evenly lubricate the contacting steel balls by itself. The oiled steel balls can lubricate the inner track surface of the nut by themselves to form a better lubrication pair, which can reduce the contact area between the screw and the steel balls. After storing the lubricating oil, a micro-oil pool is formed, which forms a dynamic pressure lubrication effect during the high-speed reciprocating motion of the screw pair, further reducing friction and frictional heat, reducing wear and noise, making the steel balls move more smoothly, and using the least amount of lubricating oil to achieve a better lubrication effect, reducing the waste of lubricating oil and reducing the frequency of adding lubricating oil. The replacement method is the same as that of the cleaning head.

[0098] Although the present invention has been described in detail above by general description and specific embodiments, it is obvious to those skilled in the art that some modifications or improvements can be made to the present invention. Therefore, these modifications or improvements made without departing from the spirit of the present invention all belong to the scope of protection claimed by the present invention.

[0099] The matters not described in detail in the present invention are the prior art or common knowledge in the field.

Claims

1. A roller screw track surface roughening method based on numerically controlled oscillating cutting, characterized in that: The CNC lathe is a horizontal CNC lathe, and the turning tool is a hard-coated turning tool with a tool tip angle of 25° and an arc radius of 0.05 mm. The control module in the CNC lathe grids the spiral track surface of the ball screw into a number of virtual spirals with randomly distributed spacing. Each virtual spiral has the same lead as the spiral track surface, and each virtual spiral is composed of a number of virtual spiral points with random axial spacing. The roughening process includes the following steps: Step 1: Perform ultrasonic cleaning on the ball screw after fine processing for more than two times to remove oil and debris on the track surface of the ball screw, and dry it naturally in the air after cleaning; Step 2: Clamp the cleaned and dried screw rod on the CNC lathe through the chuck and the center, and ensure that the spatial posture of the screw rod's rotation axis is horizontal; the spindle of the CNC lathe drives the screw rod to rotate through the chuck; Step 3, the control module in the CNC lathe controls the tool tip to be positioned to the empty tool position of the first virtual spiral point on the first virtual spiral, that is, the position leaving a radial feed gap of 1 mm, controls the tool to radially feed to the first virtual spiral point of the first virtual spiral and quickly retract, completes the turning of the first virtual spiral point of the first virtual spiral along with the rotation of the spindle, and forms a long strip micro-pit at the first virtual spiral point; when the tool tip returns to the empty tool position of the first virtual spiral point on the first virtual spiral, the tool tip is axially displaced to the empty tool position of the second virtual spiral point on the first virtual spiral, controls the tool to radially feed to the second virtual spiral point of the first virtual spiral and quickly retract, completes the turning of the second virtual spiral point on the first virtual spiral, and forms a long strip micro-pit at the second virtual spiral point; repeats the random oscillation turning of all virtual spiral points of the first virtual spiral, and forms a plurality of long strip micro-pits along the first virtual spiral; Step 4: The control module in the CNC lathe controls the tool tip to return to the empty tool position of the first virtual spiral point on the first virtual spiral, and axially displace to the empty tool position of the first virtual spiral point on the second virtual spiral, and complete the random oscillation turning of all virtual spiral points of the second virtual spiral in accordance with the method of step 3, and form a plurality of long strip micro-pits along the second virtual spiral; Step 5: The method of step 4 is consistent with that of step 4, completing the random oscillation turning of all virtual spiral points on all virtual spirals, that is, completing the roughening treatment of the screw spiral track surface.

2. The roller screw track surface roughening treatment method based on CNC oscillation cutting according to claim 1 is characterized in that: The distance between the first virtual spiral and the edge of the spiral track surface is 0.1 mm; the axial spacing between adjacent virtual spirals is randomly selected in the range of 0.1~0.5 mm; the axial spacing between adjacent virtual spiral points is randomly selected in the range of 0.1~0.2 mm; the length of each virtual spiral point is randomly selected in the range of 20~30 μm.

3. The roller screw track surface roughening treatment method based on CNC oscillation cutting according to claim 1 is characterized in that: The width of the long strip micro-pit depends on the arc radius of the turning tool tip angle, and the length of the long strip micro-pit depends on the contact time between the turning tool tip and the screw rod. The contact time between the turning tool tip and the screw rod is randomly selected in the range of 0.003~0.01 s.

4. The roller screw track surface roughening treatment method based on CNC oscillation cutting according to claim 1 is characterized in that: Repeat steps 3-5 to perform roughening treatment on the spiral track surface of the screw rod once or more times.

5. A roller screw track surface roughening treatment method based on CNC oscillation cutting according to any one of claims 1 to 3, characterized in that: The ball screw comprises a screw rod (1), a nut (2) with an integrated reverser, a steel ball, and an oil supply cleaner (5) fixedly mounted at one end or both ends of the nut (2). The oil supply cleaner comprises A disc body (51), wherein the inner diameter of the central circular hole (511) of the disc body (51) is larger than the outer diameter of the screw rod (1), and a plurality of axial through holes (512) are evenly arranged on the end surface; a plurality of axial screw holes (21) are arranged on one end or both end surfaces of the nut (2) corresponding to the plurality of axial through holes (512); a fastening screw passes through the axial through hole (512) and is screwed with the axial screw hole (21) to fix the oil supply cleaner (5) on the nut (2); two stepped holes (513) with a smaller inner hole and a larger outer hole are arranged opposite to each other along the radial direction of the disc body (51); the outer section of the larger hole of the stepped hole (513) is a threaded section; the axes of the two stepped holes (513) are spaced half the pitch of the screw rod (1); one of the stepped holes (513) is an oil filling hole, and the other stepped hole (513) is a cleaning hole; An oil supply head (52) is in the shape of a stepped truncated cone as a whole, comprising a large truncated cone that is clearance-matched with the large hole of the stepped hole (513) and a small truncated cone that is clearance-matched with the small hole of the stepped hole (513), and a central oil passage (521) is provided in the center along the axial direction; 1 cleaning head (53), the rest of which is the same structure as the oil supply head (52), except that it does not have a central oil passage (521); Two sealing screws (54) are screwed to the threaded sections of the two stepped holes (513) respectively; Two springs (55) have one end abutting against the oil supply head (52) or the cleaning head (53) and the other end abutting against the sealing screw (54).

6. The roller screw track surface roughening treatment method based on CNC oscillation cutting according to claim 4 is characterized in that: The small round cones of the oil supply head (52) and the cleaning head (53) extend out of the step hole (513) of the disc body (51) and abut against the spiral track surface (11) of the screw rod (1).

7. The method for roughening the roller screw track surface based on numerically controlled oscillating cutting according to claim 4, characterized in that: The free ends of the small frustums of the oil supply head (52) and the cleaning head (53) are hemispherical, and the diameters thereof are equal to the diameters of the steel balls.

8. The roller screw track surface roughening treatment method based on CNC oscillation cutting according to claim 4 is characterized in that: The oil supply head (52) is located at the upper part of the disc body, and the cleaning head (53) is located at the lower part of the disc body.

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