Ball screw nut internal thread grinding method

Abstract

A method for grinding the internal thread of a ball screw nut is implemented according to the following steps: S1, drawing a model diagram of the internal nut of a ball screw in a three-dimensional drawing software, and importing the initial grinding position and the distance of the non-roller surface on the x-axis into a processing device after measuring the distance of the non-roller surface on the x-axis; S2, the processing device grinds the grinding wheel to its initial grinding position and the rolling surface of the internal thread of the ball screw nut; S3, when the grinding wheel reaches the initial position of the non-roller surface, the grinding wheel withdraws along the x-axis and moves according to the distance on the x-axis in step S1; S4, after moving the distance on the x-axis in step S1, the grinding wheel contacts the rolling surface on the x-axis to continue processing. The beneficial effect of the present invention is that by avoiding the non-roller surface, the ineffective working time of the grinding wheel in the non-target area is reduced, thereby extending the service life of the grinding wheel.

Description

Technical Field

[0001] The invention relates to a method for processing the internal thread of a ball screw, and in particular to a method for grinding the internal thread of a ball screw nut. Background Art

[0002] In the prior art, the grinding of the internal threads of ball screw nuts is usually carried out using a special grinder, and the spiral raceway on the inner wall of the nut is precisely ground by a grinding wheel. To ensure that the steel balls can circulate smoothly in the raceway, the entire length of the raceway needs to be covered during the grinding process, including the circulation path and non-circulation path of the steel balls. Specifically, the grinding wheel performs profile grinding on the internal threads according to the predetermined pitch and profile, and the diamond roller is used to dress the grinding wheel to ensure its accuracy. This processing method relies on high-precision equipment and strict process control, and can achieve high surface quality and dimensional accuracy, meeting the basic functional requirements of the ball screw.

[0003] However, the prior art has obvious defects. Although the current grinding method can include a circulation path for the steel ball and meet the requirements for normal rolling of the steel ball, the grinding range covers the non-circulation path, which increases the grinding length and significantly increases the use cost of the grinding wheel and diamond roller. In addition, due to the existence of the non-circulation raceway, the steel ball is easily misinstalled into the non-circulation area during manual or equipment assembly, which in turn causes a series of problems. For example, the ball screw may experience undesirable phenomena such as jamming and abnormal noise during use, and may even cause the steel ball to impact the reverser, causing the reverser to fail, and ultimately causing the product to lose its function, seriously affecting its service life and reliability. Summary of the invention

[0004] In view of the deficiencies in the prior art, the present invention provides a method for grinding the internal thread of a ball screw nut by not grinding the non-raceway surface to increase the life of the grinding wheel.

[0005] To achieve the above object, the technical solution of the present invention is as follows: A method for grinding the internal thread of a ball screw nut is implemented according to the following steps: S1, drawing a model diagram of the inner nut of the ball screw in a three-dimensional drawing software, measuring the distance of the non-raceway surface on the x-axis, and then importing the grinding initial position and the distance of the non-raceway surface on the x-axis into the processing equipment; S2, the processing equipment grinds the grinding wheel to its initial grinding position and grinds the raceway surface of the internal thread of the ball screw nut; S3, when the grinding wheel reaches the initial position of the non-raceway surface, the grinding wheel withdraws along the x-axis and moves according to the distance on the x-axis in step S1; S4, after moving the distance on the x-axis in step S1, the grinding wheel contacts the raceway surface on the x-axis to continue machining.

[0006] The beneficial effects of the present invention are as follows: by pre-drawing a model diagram of the nut inside the ball screw in three-dimensional mapping software and accurately calculating the distance of the non-raceway surface on the x-axis, it is possible to ensure that the processing equipment accurately positions the initial grinding position. At the same time, by avoiding the non-raceway surface, the ineffective working time of the grinding wheel in the non-target area is reduced, thereby extending the service life of the grinding wheel. In addition, this method controls the motion trajectory of the grinding wheel through an automated program, avoids errors that may be caused by manual intervention, and improves processing accuracy and efficiency. As a preferred method, a parametric modeling function can be set in the three-dimensional mapping software to quickly generate corresponding model diagrams according to different ball screw specifications, further improving the consistency of design and processing.

[0007] Further, step S3 is implemented according to the following steps: S31, respectively arranging distance measuring plates for measuring the distance between the grinding wheel and the non-rolling surface on the z-axis at the initial position and the final position of the non-rolling surface; S32, connect the distance measuring board to the processing equipment control center, and set the safety distance of the distance measuring board. After the grinding wheel enters the safety distance, the distance measuring board sends a signal to the processing equipment control center to make the grinding wheel withdraw along the x-axis.

[0008] By setting distance measuring plates at the initial and final positions of the non-raceway surface, the position status of the grinding wheel can be monitored in real time to prevent it from entering the non-raceway area and causing unnecessary wear or damage. This design not only realizes a fully automated operation process, but also significantly reduces the need for manual monitoring and improves overall production efficiency. As a preferred method, the distance measuring plate can use a high-precision laser sensor, combined with the feedback control system of the processing equipment, to dynamically adjust the moving speed of the grinding wheel, thereby further optimizing the stability and safety of the grinding process.

[0009] Furthermore, the ranging plate is U-shaped, and its inner opening is consistent with the opening of the mounting groove on the inner nut of the ball screw for installing the reverser. The ranging plate is located at one end of the inner thread surface of the inner nut of the ball screw and abuts against the side of the non-raceway surface on the thread surface.

[0010] The distance measuring plate is designed as a U-shaped structure, and its inner opening is consistent with the opening of the reverser installed on the inner nut of the ball screw, which can effectively fit the thread surface and ensure the accuracy of the distance measurement data. At the same time, because the distance measuring plate is directly against the thread surface, it can better adapt to complex processing environments and avoid data deviations caused by external interference. This design also makes full use of the internal space of the ball screw, making the layout of the distance measuring plate more compact and reasonable. As a preferred method, the material of the distance measuring plate can be selected from high-strength wear-resistant materials to cope with mechanical stress and thermal deformation problems that may occur during long-term operation.

[0011] Furthermore, the safety distance of the distance measuring plate is set on the inner nut of the ball screw, and the mounting groove for mounting the reverser is located between the end point on one side of the raceway surface and the end point on the non-raceway surface side.

[0012] Setting the safe distance of the distance measuring plate within the non-raceway surface can not only avoid the need for operators to constantly observe the three-axis movement of the processing equipment to achieve automated production, but also ensure that the raceway surface is ground. This design fully considers the characteristics of the movement trajectory of the rolling body during the actual processing process, taking into account the reliability of automated operation and the durability of the grinding wheel. As a preferred method, the optimal safe distance range of ball screws of different specifications can be determined through experimental tests and preset in the control program of the processing equipment so that it can be flexibly adjusted to meet diverse needs.

[0013] Further, the step S2 is implemented according to the following steps: S21, when the grinding wheel is at the initial grinding position, measuring the distance between the grinding wheel and the initial position of the inner nut of the ball screw on the x-axis by using a gauge; S22, if there is a gap between the position of the grinding wheel and the initial position of the inner nut of the ball screw on the x-axis, the initial position of the grinding wheel is manually adjusted.

[0014] By using a gauge to measure the distance between the grinding wheel and the initial position of the nut in the ball screw, the initial position of the grinding wheel can be effectively corrected, thereby ensuring the accuracy of subsequent grinding operations. If a gap is found, the operator is allowed to manually fine-tune the position of the grinding wheel, further enhancing the flexibility and adaptability of the system. This dual protection mechanism not only improves the processing quality, but also reduces the product scrap rate caused by equipment errors. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 A partial cross-sectional view of an inner nut of a ball screw according to an embodiment of the present invention; Figure 2 Schematic diagram of the motion trajectory of the grinding wheel in an embodiment of the present invention (in the figure, A is the center line of the nut inside the ball screw, and B is the safety distance of the distance measuring plate). DETAILED DESCRIPTION

[0016] A method for grinding an internal thread of a ball screw nut according to an embodiment of the present invention is as follows Figure 1-2 As shown and implemented as follows: S1, drawing a model diagram of the ball screw inner nut 1 in a three-dimensional drawing software, measuring the distance of the non-raceway surface 111 on the x-axis, and then importing the grinding initial position and the distance of the non-raceway surface 111 on the x-axis into the processing equipment; S2, the processing equipment grinds the grinding wheel 3 to its initial grinding position and grinds the raceway surface 112 of the internal thread of the ball screw nut; Step S2 is implemented according to the following steps: S21, when the grinding wheel 3 is at the initial grinding position, the distance between the grinding wheel 3 and the initial position of the inner nut of the ball screw on the x-axis is measured by a gauge; S22, if there is a gap between the position of the grinding wheel 3 and the initial position of the inner nut of the ball screw on the x-axis, the initial position of the grinding wheel 3 is manually adjusted.

[0017] S3, when the grinding wheel 3 reaches the initial position of the non-raceway surface 111, the grinding wheel 3 withdraws along the x-axis and moves according to the distance on the x-axis in step S1; Step S3 is implemented according to the following steps: S31, respectively arranging a distance measuring plate 2 for measuring the distance between the grinding wheel 3 and the non-rolling surface on the z-axis at the initial position and the final position of the non-rolling surface; S32, connect the distance measuring plate 2 to the processing equipment control center, and set the safety distance of the distance measuring plate 2. After the grinding wheel 3 enters the safety distance, the distance measuring plate 2 sends a signal to the processing equipment control center to make the grinding wheel 3 withdraw along the x-axis.

[0018] In step S3, the distance measuring plate 2 is U-shaped, and its inner opening is consistent with the mounting groove 12 for mounting the deflector on the inner nut 1 of the ball screw, and one end of the distance measuring plate 2 is located on the inner thread surface 11 of the inner nut of the ball screw, and is against the side of the non-raceway surface 111 on the thread surface. And the safety distance of the distance measuring plate 2 is set between the end point of the mounting groove 12 for mounting the deflector on the inner nut 1 of the ball screw, which is located on one side of the raceway surface 112 and the end point of the non-raceway surface 111. In addition, in order to ensure the grinding effect and improve the life of the moxielun, the setting of the safety distance is preferably such that the vertex of the outer diameter of the grinding wheel 3 passes through the end point of the mounting groove 12 for mounting the deflector and is located on one side of the raceway surface 112, and the grinding wheel 3 has not yet contacted the side of the non-raceway surface.

[0019] S4, after moving the distance on the x-axis in step S1, the grinding wheel 3 contacts the raceway surface 112 on the x-axis to continue machining.

[0020] The above embodiment is only one of the preferred specific embodiments of the present invention. Common changes and substitutions made by those skilled in the art within the scope of the technical solution of the present invention are all included in the protection scope of the present invention.

Claims

1. A method for grinding the internal thread of a ball screw nut is implemented according to the following steps: S1, drawing a model diagram of the inner nut of the ball screw in a three-dimensional drawing software, measuring the distance of the non-raceway surface on the x-axis, and then importing the grinding initial position and the distance of the non-raceway surface on the x-axis into the processing equipment; S2, the processing equipment grinds the grinding wheel to its initial grinding position and grinds the raceway surface of the internal thread of the ball screw nut; S3, when the grinding wheel reaches the initial position of the non-raceway surface, the grinding wheel withdraws along the x-axis and moves according to the distance on the x-axis in step S1; S4, after moving the distance on the x-axis in step S1, the grinding wheel contacts the raceway surface on the x-axis to continue machining.

2. A method for grinding internal threads of a ball screw nut according to claim 1, characterized in that: The step S3 is implemented according to the following steps: S31, respectively arranging distance measuring plates for measuring the distance between the grinding wheel and the non-rolling surface on the z-axis at the initial position and the final position of the non-rolling surface; S32, connect the distance measuring board to the processing equipment control center, and set the safety distance of the distance measuring board. After the grinding wheel enters the safety distance, the distance measuring board sends a signal to the processing equipment control center to make the grinding wheel withdraw along the x-axis.

3. A method for grinding internal threads of a ball screw nut according to claim 2, characterized in that: The distance measuring plate is U-shaped, and its inner opening is consistent with the opening of the mounting groove for mounting the reverser on the inner nut of the ball screw. The distance measuring plate is located at one end of the inner thread surface of the inner nut of the ball screw, and abuts against the side of the non-raceway surface of the thread surface.

4. A method for grinding internal threads of a ball screw nut according to claim 2, characterized in that: The safety distance of the distance measuring plate is set on the inner nut of the ball screw. The mounting groove for mounting the reverser is located between the end point on one side of the raceway surface and the end point on the non-raceway surface.

5. The method for grinding the internal thread of a ball screw nut according to claim 1, characterized in that: The step S2 is implemented according to the following steps: S21, when the grinding wheel is at the initial grinding position, measuring the distance between the grinding wheel and the initial position of the inner nut of the ball screw on the x-axis by using a gauge; S22, if there is a gap between the position of the grinding wheel and the initial position of the inner nut of the ball screw on the x-axis, the initial position of the grinding wheel is manually adjusted.

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