A method for turning a lubrication groove of a copper sleeve

Abstract

The present invention discloses a method for turning a lubricating groove of a copper sleeve, which is specifically implemented according to the following steps: step 1, planning a tool path, and preparing a CNC program for turning a spiral groove; step 2, placing the copper sleeve with a processed shape on a lathe; step 3, pressing a dial indicator on the outer circle of the copper sleeve and the large end face of the copper sleeve for alignment; step 4, determining a workpiece coordinate system; step 5, moving the tool to a starting position away from the large end face of the copper sleeve and close to the center of rotation, and starting the lathe for processing. The present invention can make the machine tool shaft move smoothly through the optimal tool path, realize the effective processing of the spiral groove, and is simple to process. It is ensured that the spiral groove does not directly pass through the outer edge of the inner wall of the copper sleeve, and can maximize the existence of a lubricating oil film, improve the reliability of lubrication, and extend the service life of the copper sleeve.

Description

Technical Field

[0001] The invention belongs to the technical field of mechanical processing and relates to a turning method for a lubrication groove of a copper sleeve. Background Art

[0002] Copper sleeves are a common typical part in mechanical equipment, often used in low-speed, heavy-loaded rotating pairs. Lubrication grooves are opened in the inner hole to facilitate uniform lubrication of grease. The lubrication grooves of copper sleeves are in various forms. The most common ones are a number of straight grooves evenly distributed along the axial direction of the inner wall of the hole or straight grooves with ring grooves. The traditional processing method is slotting, milling, or first turning the ring groove and then slotting (milling) the straight groove.

[0003] At present, there is a copper sleeve lubrication groove in the form of a spiral groove. The characteristic is that the starting point and end point of the spiral groove are not connected to the two ends of the copper sleeve to prevent grease leakage. When the contained part rotates forward and reversely, the spiral driving effect of the spiral groove is used to make the grease coating more even, improving the lubrication effect. This type of lubrication groove cannot be processed by traditional ordinary turning methods because the starting point and end point of the spiral groove are not connected to the two ends of the copper sleeve and there are no empty tool grooves. If it is processed by a CNC lathe, the usual turning procedure is that the tool Z axis fast forwards to the starting point of the thread, the X axis leaves the hole wall a safe distance, and then the X axis linearly interpolates to the cutting depth, and then performs thread cutting interpolation, and retracts the tool after reaching the end point of the thread, and the X axis quickly leaves the workpiece. However, commonly used CNC lathes (except turning and milling machining centers) do not have C-axis function, that is, the spindle is not a CNC axis, and cannot use program control to start thread turning from the required phase point. After the tool reaches the starting point of the thread, before the thread interpolation instruction takes effect, the lathe spindle must idle for a certain angle (randomly). The CNC system passively waits until the spindle encoder sends a starting point instruction before thread interpolation begins. At this time, since the thread starting point is not on the end face of the workpiece, the tool has actually cut into the workpiece, and the idling stroke will leave an annular groove, which obviously does not meet the requirements of the drawing. Summary of the invention

[0004] The purpose of the present invention is to provide a method for turning a lubricating groove of a copper sleeve, which solves the problem that the existing conventional technology cannot turn a spiral groove that is not directly connected to the two end surfaces of the copper sleeve.

[0005] The technical solution adopted by the present invention is a method for turning a copper sleeve lubrication groove, which is specifically implemented according to the following steps:

[0006] Step 1: Plan the tool path and prepare the NC program for turning spiral grooves;

[0007] Step 2: Place the copper sleeve with processed shape on the lathe;

[0008] Step 3: Use a dial indicator to align the outer circle and large end surface of the copper sleeve;

[0009] Step 4: Determine the workpiece coordinate system;

[0010] Step 5: Move the tool to the starting position away from the large end face of the copper sleeve and close to the center of rotation, and start the lathe for processing.

[0011] The present invention is also characterized in that:

[0012] The specific process of step 1 is: plan the A, B, C, D, and E segments in the tool path in sequence, and the tool fast-forwards to the end position of segment A, and the coordinates of the end position of segment A are (X0, Z25); segment B is for tapered thread interpolation, and the end coordinates are (X=R0, Z-10); among them, the X-axis coordinate is parameter R0, the initial value is the inner diameter of the copper sleeve 50, the step value is set to 0.3, which is the cutting depth of each cut, and the pitch is set to 60. When cutting into the workpiece for tapered thread interpolation, the tool is moving in vain and does not cut; segment C is for processing the spiral groove, and the coordinates of the end point of the spiral groove are (X=R0, Z-70); segment D is for fast-forward retraction, and the coordinates of the end point are (X10, Z-70); segment E is for the tool to quickly retract to the end point of segment A (X0, Z25) so that the program can be cycled.

[0013] Step 4: Use the trial cutting method to test the inner hole of the copper sleeve to determine the X-axis zero point. The X-axis zero point is the rotation center of the lathe spindle. Test the large end of the copper sleeve to determine the Z-axis zero point, thereby determining the workpiece coordinate system.

[0014] The alignment in step 3 is within 0.05 mm.

[0015] In step 1, the cutting parameters are spindle forward speed of 20RPM and feed rate of 600mm / min.

[0016] In step 2, the copper sleeve is in a sleeve structure, one axial end of the copper sleeve is a large end face, and the other end is a small end face. A groove is radially provided on the outer surface of the copper sleeve, and a through hole is provided in the groove. A three-jaw chuck is used to clamp the outer circle of the small end of the copper sleeve.

[0017] Step 1: Use R5 arc left-biased inner hole turning tool.

[0018] In step 1, the blade is a Φ10mm carbide circular blade.

[0019] The beneficial effects of the present invention are as follows: the present invention provides a method for turning a lubricating groove of a copper sleeve, which can make the machine tool shaft move smoothly by optimizing the tool path, realize the turning of the spiral groove, and is simple to process. The spiral groove does not directly pass through the outer edge of the inner wall of the copper sleeve, which can maximize the existence of the lubricating oil film, improve the reliability of lubrication, and reduce wear. The present invention provides a method for turning a lubricating groove of a copper sleeve, which reduces processing errors and improves processing accuracy. The present invention plays an important role in the standardization and modularization of the components of the copper sleeve lubricating spiral slideway, is conducive to large-scale production and promotion, and plays a decisive role in improving production efficiency, reducing use costs, and meeting customer needs. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the 3D structure of the lubricating spiral groove of the copper sleeve of the present invention;

[0021] Figure 2 It is a cross-sectional schematic diagram of the lubricating spiral groove of the copper sleeve of the present invention;

[0022] Figure 3 It is a side view of the lubricating spiral groove of the copper sleeve of the present invention;

[0023] Figure 4 The present invention is a schematic diagram of a tool path for a CNC lathe to turn a spiral groove according to the turning method of the present invention.

[0024] In the figure, 1. copper sleeve, 2. spiral groove, 3. groove, 4. through hole, 5. tool, 6. tool path. DETAILED DESCRIPTION

[0025] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0026] The present invention provides a method for turning a lubrication groove of a copper sleeve, such as Figure 1 As shown, the copper sleeve 1 is a sleeve structure, one axial end of the copper sleeve 1 is a large end face, and the other end is a small end face. A groove 3 is radially provided on the outer surface of the copper sleeve 1, and a through hole 4 is provided in the groove 3. According to the principle that the CNC lathe will not stop at the connection point of the two sections of threads when continuously turning two connected sections of threads (variable pitch or tapered threads are both possible), a tapered thread turning program is added in front of the CNC program segment for turning the spiral lubrication groove of the copper sleeve, thereby designing the tool paths of sections A, B, C, D, and E, of which the section B is the tapered thread turning section, in order to make the tool be outside the workpiece at the starting position of the tapered thread processing, so that when the ordinary CNC lathe is turning the thread, the tool waits at the starting position of the thread, while the workpiece is transferred to the outside of the workpiece during the rotation process, thereby avoiding overcutting.

[0027] The present invention provides a method for turning a lubrication groove of a copper sleeve, which is specifically implemented according to the following steps:

[0028] Step 1: Plan the tool path and prepare the NC program for turning spiral grooves;

[0029] The specific process of step 1 is: plan the A, B, C, D, and E segments of tool path 6 in sequence, such as Figure 4 As shown: the tool fast forwards to the end position of segment A, the coordinates of the end position of segment A are (X0, Z25); segment B is tapered thread interpolation, the end coordinates are (X=R0, Z-10); where the X-axis coordinate is parameter R0, the initial value is the inner diameter of the copper sleeve 50, the step value is set to 0.3, which is the cutting depth of each cut, such as Figure 2 and Figure 3As shown, the pitch is set to 60, and the tool is moving in the air when cutting into the workpiece taper thread interpolation, without cutting; Segment C is for processing spiral groove 2, and the coordinates of the end point of spiral groove 2 are (X=R0, Z-70); Segment D is for fast forward and retract, and the coordinates of the end point are (X10, Z-70); Segment E is for the tool to quickly retract to the end point of segment A (X0, Z25), so that the program can be cycled. Spiral groove 2 needs to be completed by rough turning and fine turning for multiple times. The rough machining is completed after the CNC program is cycled 13 times, leaving a 0.1mm fine machining allowance. The coordinates of the end point of segment B of the CNC program are changed to (X54, Z-10), and the fine machining can be completed by running the program again.

[0030] The tool used is an R5 arc left-biased inner hole turning tool; the blade uses a Φ10mm carbide circular blade; the spindle forward speed in the cutting parameters is 20RPM, and the feed rate is 600mm / min; if the cutting depth of each cut is set to 0.2mm, that is, the step value of parameter R0 is 0.2, then 20 cycles can complete the processing.

[0031] Step 2: Place the copper sleeve 1 with processed shape on a lathe, and use a three-jaw chuck to clamp the outer circle of the small end of the copper sleeve;

[0032] Step 3: Use a dial indicator to align the outer circle and large end surface of the copper sleeve to within 0.05mm.

[0033] Step 4: Determine the workpiece coordinate system;

[0034] Use the trial cutting method to test the inner hole of copper sleeve 1 to determine the X-axis zero point. The X-axis zero point is the rotation center of the lathe spindle. Test cutting and tool setting are performed on the large end of the copper sleeve to determine the Z-axis zero point, thereby determining the workpiece coordinate system.

[0035] Step 5: Move the tool to the starting position away from the large end surface of the copper sleeve 1 and close to the center of rotation, select the tool path, and start the lathe for processing.

[0036] In an embodiment of a method for turning a lubricating groove of a copper sleeve of the present invention, the numerical control system adopts SINUMERIK810T, and the program runs for about 40-45 seconds, thereby forming a spiral groove 2 extending spirally along the circumferential direction of the inner wall of the copper sleeve 1.

[0037] The working principle of the turning method of the copper sleeve lubrication groove of the present invention is that two consecutive sections of thread interpolation are performed by a CNC lathe, the interpolation process is continuous, there is no spindle idling waiting problem in the middle, a section of tapered thread interpolation is added before turning the spiral groove 2, the spindle idling waiting position is moved to the outside of the workpiece, the end point of the tapered thread is just at the starting point of the spiral groove 2, at this time the tool normally cuts into the workpiece, and the tapered thread interpolation is used so that the section of the tool path is outside the workpiece. In this process, the tool does not participate in cutting, avoiding the problem of generating annular grooves in conventional methods, thereby perfectly solving the processing problem of the spiral lubrication groove and having high processing efficiency.

[0038] The tool path planning of the present invention is an important link in the CNC machining process of the spiral groove 2 on the curved surface. The optimized tool path can significantly improve the efficiency of curved surface machining and reduce the energy consumption of the machine tool. The tool path optimization with the spindle speed, feed rate, pitch, etc. as constraints can make the machine tool axis move smoothly through the optimal tool path, and realize the effectiveness and practicality of the spiral groove 2 machining. The turning method of the copper sleeve lubrication groove of the present invention is simple to process, and the spiral groove 2 is not directly connected with the outer edge of the inner wall of the copper sleeve 1, which can maximize the existence of the lubricating oil film, improve the reliability of lubrication, reduce wear; reduce the wear of the copper sleeve body and extend its service life; extend the time for the lubricating oil to flow out of the spiral groove 2, so that the lubricating oil lubricates and flows out along the spiral groove 2, ensuring the lubricity of the copper sleeve body 1, and at the same time ensuring fluidity.

Claims

1. A method for turning a lubrication groove of a copper sleeve, characterized in that: Follow the steps below to implement it: Step 1: Plan the tool path (6) and prepare the NC program for turning the spiral groove; Step 2, placing the copper sleeve (1) with processed shape on a lathe; Step 3: Use a dial indicator to align the outer circle and large end surface of the copper sleeve; Step 4: Determine the workpiece coordinate system; Step 5, the tool (5) moves to a starting position away from the large end surface of the copper sleeve (1) and close to the rotation center, and the lathe is started for processing; The specific process of step 1 is as follows: planning the A, B, C, D, and E segments in the tool path (6) in sequence, the tool (5) fast forwards to the end position of segment A, and the coordinates of the end position of segment A are (X0, Z25); segment B is for tapered thread interpolation, and the end coordinates are (X=R0, Z-10); wherein the X-axis coordinate is parameter R0, the initial value is the inner diameter of the copper sleeve 50, the step value is set to 0.2, which is the cutting depth of each cut, the pitch is set to 60, and the tool is in idle motion when cutting into the workpiece tapered thread interpolation, and does not cut; segment C is for machining the spiral groove (2), and the end coordinates of the spiral groove (2) are (X=R0, Z-70); segment D is for fast forward and retraction, and the end coordinates are (X10, Z-70); segment E is for the tool to quickly retract to the end point of segment A (X0, Z25), and then cycle is performed; In step 4, the inner hole of the copper sleeve (1) is tested by a trial cutting method to determine the X-axis zero point, the X-axis zero point being the rotation center of the lathe spindle, and the Z-axis zero point is tested by a trial cutting method at the large end of the copper sleeve to determine the Z-axis zero point, thereby determining the workpiece coordinate system; The alignment in step 3 is within 0.05 mm.

2. A method for turning a copper sleeve lubrication groove according to claim 1, characterized in that: In step 1, the cutting parameters are: the spindle forward speed is 20RPM, and the feed rate is 600mm / min.

3. The turning method of a copper sleeve lubrication groove according to claim 1, characterized in that: In step 2, the copper sleeve (1) is in a sleeve structure, one axial end of the copper sleeve (1) is a large end face, and the other end is a small end face. A groove (3) is radially provided on the outer surface of the copper sleeve (1), and a through hole (4) is provided in the groove (3). A three-jaw chuck is used to clamp the outer circle of the small end of the copper sleeve.

4. A method for turning a copper sleeve lubrication groove according to claim 1, characterized in that: The tool (5) in step 1 is an R5 arc left-biased inner hole turning tool.

5. A method for turning a copper sleeve lubrication groove according to claim 4, characterized in that: In step 1, the blade is a Φ10 mm hard alloy circular blade.

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