Numerical control grinding machine main shaft rigidity detection device and method

Abstract

The invention discloses a numerical control grinding machine spindle rigidity detection device and method, and belongs to the technical field of machinery, the numerical control grinding machine spindle rigidity detection device comprises a spindle applied to a numerical control grinding machine, one end of a spindle body in the spindle is sleeved with a grinding wheel, and a force application mechanism for applying different forces to the grinding wheel is arranged outside the grinding wheel; an oil film pressure sensor for detecting the pressure of an oil film in an oil cavity is inserted in the oil cavity of the main shaft and is in signal connection with a display for displaying a detected value; the other end of the main shaft body is provided with a plurality of dial indicators which are circumferentially and uniformly arranged with the center of the main shaft body as the circle center. According to the invention, force is applied to the rotating main shaft through the force application mechanism, and the offset of the main shaft body during rotation can be measured according to the reading of the dial indicator, so that the radial rigidity of the main shaft body can be conveniently detected in the main shaft design and manufacturing process, and the offset of the main shaft body can be adjusted to a proper value by adjusting the oil quantity in each oil cavity of the main shaft.

Description

Technical Field

[0001] The invention belongs to the field of mechanical technology, and in particular relates to a device and method for detecting the rigidity of a spindle of a numerically controlled grinder. Background Art

[0002] The spindle of a CNC grinding machine refers to the axis that drives the workpiece or tool to rotate on the machine tool. It is usually composed of a spindle, bearings and transmission parts (gears or pulleys). In the machine, it is mainly used to support transmission parts such as gears and pulleys, transmit motion and torque, such as the machine tool spindle; some are used to clamp workpieces, such as mandrels. Except for machine tools such as planers and broaching machines whose main motion is linear motion, most machine tools have spindle components. The motion accuracy and structural rigidity of the spindle components are important factors in determining the processing quality and cutting efficiency. The indicators for measuring the performance of the spindle components are mainly rotation accuracy, rigidity and speed adaptability. ① Rotation accuracy: The radial and axial runout (see form and position tolerance) that occurs in the direction that affects the processing accuracy when the spindle rotates is mainly determined by the manufacturing and assembly quality of the spindle and bearings. ② Dynamic and static rigidity: Mainly determined by the bending rigidity of the spindle, the rigidity and damping of the bearings. ③ Speed ​​adaptability: The maximum allowable speed and speed range are mainly determined by the structure and lubrication of the bearings, as well as the heat dissipation conditions.

[0003] Spindle rigidity is an important indicator of the grinding head of a CNC grinder, which determines the grinding efficiency of the grinder. Generally, empirical data is used to design the oil chamber and spindle, and the spindle rigidity data is derived according to the grinding parameters after the machine tool is put into use, which has a very low accuracy. Not only can the spindle rigidity data not be visualized, but the data cannot be used to make adjustments during the design and production process to achieve the best effect. Summary of the invention

[0004] In order to solve the problem of low accuracy of spindle rigidity data derived in the prior art and the problem of being unable to adjust the spindle using the spindle rigidity data during the design and manufacturing process, the present invention provides a spindle rigidity detection device and method for a CNC grinder, which can detect the spindle rigidity during the spindle design and manufacturing process, and thus adjust the spindle using the detection data.

[0005] The technical solution adopted by the device and method for detecting the rigidity of a spindle of a CNC grinder of the present invention is:

[0006] A spindle rigidity detection device for a numerically controlled grinder comprises a spindle used on the numerically controlled grinder, wherein a grinding wheel is sleeved on one end of a spindle body in the spindle, a force applying mechanism for applying different forces to the grinding wheel is arranged outside the grinding wheel, an oil film pressure sensor for detecting the oil film pressure in the oil chamber is inserted into the oil chamber of the spindle, and a display for displaying the detection value is connected to the signal of the oil film pressure sensor;

[0007] The other end of the main shaft body is provided with a plurality of micrometers which are evenly arranged in the circumferential direction with the center of the main shaft body as the center of the circle.

[0008] A further improvement of the technical solution of the present invention is that the force-applying mechanism includes a plurality of fixed plates arranged circumferentially with the center of the grinding wheel as the axis, and a force-applying plate movable toward the grinding wheel is provided on the side of each fixed plate facing the grinding wheel, and a grinding wheel pressure sensor is provided on the force-applying plate, which is in contact with the grinding wheel through a wear-resistant layer and is used to detect the magnitude of the force applied by the force-applying plate to the grinding wheel, and the grinding wheel pressure sensor is connected to the display signal.

[0009] A further improvement of the above technical solution of the present invention is that: the grinding wheel pressure sensor is located at the side of the force application plate, and when the center of the force application plate is in contact with the grinding wheel, the grinding wheel pressure sensor just fits with the grinding wheel.

[0010] A further improvement of the technical solution of the present invention is that it also includes a base fixed on the ground, on which are disposed a plurality of groups of opening and closing fixing mechanisms for fixing the main shaft, and the force-applying mechanism is disposed on one of the groups of fixing mechanisms.

[0011] A further improvement of the above technical solution of the present invention is that each group of the fixing mechanisms includes a lower fixing seat fixedly connected to the base, and an upper fixing seat hinged to the lower fixing seat is arranged above the lower fixing seat.

[0012] A method for detecting the rigidity of a spindle of a CNC grinder, using any one of the above-mentioned devices for detecting the rigidity of a spindle of a CNC grinder, comprises the following steps:

[0013] S1. Place the spindle on the base, fix the spindle on the base through a fixing mechanism, and make the force-applying mechanism located outside the spindle grinding wheel; insert the oil film pressure sensor into the oil cavity of the spindle;

[0014] S2, move the force plate to apply pressure to the grinding wheel;

[0015] S3, reading the value of the oil film pressure sensor on the display, and adjusting the thickness of the film outside the oil cavity according to the value of the oil film pressure sensor;

[0016] S4, drive the spindle body to rotate, and apply the same pressure as S2 to the rotating grinding wheel, and measure the spindle offset through the micrometer in contact with the spindle body;

[0017] S5. Adjust the amount of oil in the corresponding oil chamber according to the offset of the main shaft body, and repeat step S4 until the offset of the main shaft body is at an appropriate value.

[0018] A further improvement of the above technical solution of the present invention is that a suitable value of the spindle offset in step S5 is 0.001 mm.

[0019] Due to the adoption of the above technical solution, the technical advances achieved by the present invention include:

[0020] In the present invention, force is applied to the stationary spindle through a force-applying mechanism, and the thickness of the film on the outer side of the oil chamber can be adjusted according to the value of the oil film pressure sensor, thereby adjusting the spindle to an optimal state; force is applied to the rotating spindle through the force-applying mechanism, and the radial offset of the spindle body during rotation can be measured according to the reading of the micrometer, thereby facilitating the detection of the radial rigidity of the spindle body during the design and production of the spindle, and by adjusting the amount of oil in each oil chamber of the spindle, the offset of the spindle body can be adjusted to an appropriate value.

[0021] In the present invention, the force application plate is arranged to contact the grinding wheel, so that different forces can be applied to the grinding wheel, thereby applying different forces to the spindle body; the grinding wheel pressure sensor is arranged to detect the magnitude of the force applied to the grinding wheel when the force application plate contacts the grinding wheel.

[0022] At the same time, the fixing mechanism provided in the present invention can, on the one hand, fix the main shaft on the base, and on the other hand, facilitate the installation of the force applying mechanism, and arrange multiple force applying plates in the force applying mechanism around the grinding wheel, thereby facilitating the application of forces in different directions to the grinding wheel. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 and Figure 2 It is a structural schematic diagram of a spindle rigidity detection device for a CNC grinder of the present invention;

[0024] Figure 3 It is a structural schematic diagram of a fixing plate of a spindle rigidity detection device for a CNC grinder according to the present invention;

[0025] Figure 4 It is a structural schematic diagram of the main shaft of the present invention.

[0026] In the accompanying drawings: 1, spindle; 11, film; 12, grinding wheel; 121, grinding wheel flange; 122, grinding wheel flange cover; 13, rear flange cover; 14, front bearing; 15, rear bearing; 16, sleeve; 17, shaft spacer ring; 18, shaft push ring; 19, front flange cover; 10, spindle body;

[0027] 2. Force applying mechanism; 21. Fixed plate; 22. Force applying plate; 23. Grinding wheel pressure sensor; 24. Wear-resistant layer;

[0028] 3. Micrometer; 31. Support frame;

[0029] 4. Base; 41. Fixing mechanism; 411. Lower fixing seat; 412. Upper fixing seat; 413. Lower connecting seat; 414. Upper connecting seat;

[0030] 5. Oil film pressure sensor. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solution and advantages of the present invention more clear, the present invention is further described in detail below in combination with specific implementation methods and with reference to the accompanying drawings. In the following description, the description of well-known structures and technologies is omitted to avoid unnecessary confusion of the concept of the present invention.

[0032] The present invention includes a spindle rigidity detection device and method for a numerically controlled grinding machine. The present invention can detect the radial rigidity of the spindle 1 during the design and production process of the spindle 1, so that the spindle 1 can be adjusted using the detection data.

[0033] In the present invention, the main shaft 1 is specifically set with reference to Figure 4 It can be seen that the outer side of the main shaft body 10 is provided with a sleeve 16 through the front bearing 14 and the rear bearing 15, and at the same time, the side of the front bearing 14 away from the rear bearing 15 is provided with a shaft spacer ring 17, a shaft push ring 18 and a front flange cover 19 in sequence, and the side of the rear bearing 15 away from the front bearing 14 is provided with a rear flange cover 13; continue to refer to Figure 4 It can be known that the end of the spindle body 10 close to the front bearing 14 is provided with a grinding wheel 12 sleeved on the spindle body 10 through a grinding wheel 12 flange and a grinding wheel 12 flange cover, and a film 11 is provided between the grinding wheel 12 flange and the shaft push ring 18. Specifically, a film 11 feedback device is installed in the oil path entering the oil chamber, and the film 11 is placed in the feedback device.

[0034] Embodiment 1

[0035] This embodiment provides a CNC grinding machine spindle rigidity detection device. When setting it specifically, refer to Figure 1 and Figure 2 It can be seen that the base 4 is used to place the main shaft 1, and the base 4 is provided with multiple groups of fixing mechanisms 41 for fixing the main shaft 1 on the base 4. Each group of fixing mechanisms 41 includes a lower fixing seat 411 fixedly connected to the base 4, and an upper fixing seat 412 is hinged above the lower fixing seat 411 through a hinge, and the end of the lower fixing seat 411 away from the hinge is fixedly connected to a lower connecting seat 413, and the end of the upper fixing seat 412 away from the hinge is fixedly connected to an upper connecting seat 414 that cooperates with the lower connecting seat 413.

[0036] In this embodiment, the CNC grinding machine spindle rigidity detection device further includes a force applying mechanism 2 for applying force to the grinding wheel 12. Figure 1 , Figure 2 and Figure 3It can be seen that the force-applying mechanism 2 includes a plurality of L-shaped fixing plates 21 fixed on a fixing mechanism 41 near the grinding wheel 12, and a force-applying plate 22 movable toward the grinding wheel 12 is provided on the inner side of each fixing plate 21. In this embodiment, the force-applying plate 22 can move toward the grinding wheel 12 under the action of a driving mechanism (such as pneumatic, hydraulic, electric, etc.), and at the same time, a grinding wheel 12 pressure sensor is fixedly connected to the edge of the force-applying plate 22 facing the grinding wheel 12, and a wear-resistant layer 24 matching the grinding wheel 12 is fixedly connected to the side of the grinding wheel 12 of the grinding wheel 12 pressure sensor. When the center position of the force-applying plate 22 fits with the grinding wheel 12, the wear-resistant layer 24 just fits with the grinding wheel 12.

[0037] In this embodiment, an oil film pressure sensor 5 extending into the oil chamber is inserted at a position of the spindle 1 corresponding to the oil chamber, and the oil film pressure sensor 5 and the grinding wheel 12 pressure sensor in this embodiment are both connected to the display signal.

[0038] Continue to refer Figure 1 and Figure 2 A plurality of micrometers 3 for detecting the radial rigidity of the spindle body 10 are evenly arranged circumferentially on one end of the base 4 away from the grinding wheel 12 of the spindle 1 through a support frame 31, and each micrometer 3 is in contact with one end of the spindle body 10 away from the grinding wheel 12.

[0039] Embodiment 2

[0040] Based on the first embodiment, this embodiment provides a method for detecting the rigidity of a spindle of a CNC grinding machine, comprising the following steps:

[0041] S1. First, rotate the upper fixing seat 412 to open the fixing mechanism 41, then place the spindle 1 on the lower fixing seat 411, adjust the position of the spindle 1 so that the grinding wheel 12 is located between the multiple force plates 22 of the force mechanism 2, and rotate the upper fixing seat 412 in the opposite direction until the lower connecting seat 413 and the upper connecting seat 414 in the fixing mechanism 41 are in contact with each other and fixed together by bolts and nuts, thereby fixing the spindle 1 on the base 4, and then insert the oil film pressure sensor 5 into the oil chamber of the spindle 1.

[0042] S2. The force applying plate 22 is driven by the driving mechanism to move toward the grinding wheel 12 until the force applying plate 22 contacts the grinding wheel 12 and the pressure applied by the force applying plate 22 to the grinding wheel 12 is adjusted according to the detection value of the pressure sensor of the grinding wheel 12 displayed on the display.

[0043] S3. Read the value of the oil film pressure sensor 5 on the display, and adjust the thickness of the film 11 on the outside of the oil chamber according to the value of the oil film pressure sensor 5; specifically, the inner layer of the oil chamber of the main shaft 1 forms an oil film to support the main shaft body 10, and the deformation of the film 11 affects the oil flow and pressure entering the oil chamber. The thicker the film 11, the smaller the deformation. If the film 11 is too thin, the bearing capacity is insufficient. Therefore, it is necessary to select a suitable thickness of the film 11 according to the oil chamber pressure displayed by the oil film pressure sensor 5.

[0044] S4, drive the main shaft body 10 to drive the grinding wheel 12 to rotate. At this time, the force plate 22 applies the same pressure as step S2 to the rotating grinding wheel 12. The main shaft body 10 will be offset when rotating. By observing which micrometer 3 rotates and reading the value on the rotating micrometer 3, it is possible to know in which direction and by how much the main shaft body 10 is offset when rotating.

[0045] S5, the spindle body 10 stops rotating, and the amount of oil in the corresponding oil chamber is adjusted according to the radial offset and offset direction of the spindle body 10 in step S4, and then step S4 is repeated again until the radial offset of the spindle body 10 is reduced to 0.001 mm.

[0046] Embodiment 3

[0047] This embodiment is based on the first embodiment, and a micrometer 3 (not shown in the figure) for detecting the axial rigidity of the spindle body 10 is arranged at the positions of the base 4 at both ends of the grinding wheel 12 of the spindle 1. The micrometer 3 for detecting the axial rigidity of the spindle body 10 is perpendicular to the micrometer 3 for detecting the radial rigidity of the spindle body 10 in the first embodiment. In this embodiment, the two micrometers 3 for detecting the axial rigidity of the spindle body 10 are in contact with one end of the spindle body 10 away from the grinding wheel 12 of the spindle 1 and the grinding wheel 12 of the spindle 1, respectively. When the spindle body 10 rotates, the axial rigidity of the spindle body 10 can be known by observing the reading of the micrometer 3 in this embodiment, so as to facilitate the adjustment of the axial offset of the spindle body 10.

[0048] In the above embodiment, the present invention provides a spindle rigidity detection device and method for a CNC grinding machine, in which a force is applied to a stationary spindle through a force-applying mechanism, and the thickness of the film on the outside of the oil chamber can be adjusted according to the value of the oil film pressure sensor, thereby adjusting the spindle to an optimal state; a force is applied to the rotating spindle through a force-applying mechanism, and the radial offset of the spindle body during rotation can be measured according to the reading of the micrometer, thereby facilitating the detection of the radial rigidity of the spindle body during the design and production of the spindle, and adjusting the offset of the spindle body to an appropriate value by adjusting the amount of oil in each oil chamber of the spindle.

[0049] The above-described embodiments are merely descriptions of preferred implementations of the present invention, and are not intended to limit the concept and scope of the present invention. Without departing from the design concept of the present invention, various modifications and improvements made by ordinary persons in the art to the technical solution of the present invention should fall within the protection scope of the present invention, and the technical contents for which protection is sought in the present invention have been fully recorded in the claims.

Claims

1. A CNC grinding machine spindle rigidity detection device, comprising a spindle (1) used on the CNC grinding machine, characterized in that: A grinding wheel (12) is sleeved on one end of a main shaft body (10) in the main shaft (1), a force applying mechanism (2) for applying different forces to the grinding wheel (12) is arranged outside the grinding wheel (12), an oil film pressure sensor (5) for detecting the oil film pressure in the oil chamber is inserted into the oil chamber of the main shaft (1), and the oil film pressure sensor (5) is signal-connected to a display for displaying the detected value; The other end of the main shaft body (10) is provided with a plurality of micrometers (3) which are evenly arranged in the circumferential direction with the center of the main shaft body (10) as the center of the circle.

2. A CNC grinding machine spindle rigidity detection device according to claim 1, characterized in that: The force-applying mechanism (2) comprises a plurality of fixed plates (21) arranged circumferentially with the center of the grinding wheel (12) as the axis, and each fixed plate (21) is provided with a force-applying plate (22) movable in the direction of the grinding wheel (12) on the side facing the grinding wheel (12), and a grinding wheel (12) pressure sensor is provided on the force-applying plate (22) for contacting the grinding wheel (12) through a wear-resistant layer (24) and for detecting the magnitude of the force applied by the force-applying plate (22) to the grinding wheel (12), and the grinding wheel (12) pressure sensor is connected to a display signal.

3. A CNC grinding machine spindle rigidity detection device according to claim 2, characterized in that: The grinding wheel (12) pressure sensor is located at the side of the force application plate (22); when the center of the force application plate (22) fits the grinding wheel (12), the grinding wheel (12) pressure sensor just fits the grinding wheel (12).

4. The spindle rigidity detection device for a CNC grinding machine according to claim 1, characterized in that: It also comprises a base (4) fixed on the ground, on which are disposed a plurality of groups of opening and closing fixing mechanisms (41) for fixing the main shaft (1), and the force applying mechanism (2) is disposed on one group of the fixing mechanisms (41).

5. The spindle rigidity detection device for a CNC grinding machine according to claim 4, characterized in that: Each set of the fixing mechanisms (41) comprises a lower fixing seat (411) fixedly connected to the base (4), and an upper fixing seat (412) hingedly connected to the lower fixing seat (411) is arranged above the lower fixing seat (411).

6. A method for detecting the rigidity of a spindle of a CNC grinding machine, characterized in that: The use of a CNC grinding machine spindle rigidity detection device according to any one of claims 1 to 5 comprises the following steps: S1. Place the spindle (1) on the base (4), fix the spindle (1) on the base (4) by means of a fixing mechanism (41), and locate the force-applying mechanism (2) outside the grinding wheel (12) of the spindle (1); insert the oil film pressure sensor (5) into the oil cavity of the spindle (1); S2, moving the force applying plate (22) so that the force applying plate (22) applies pressure to the grinding wheel (12); and adjusting the magnitude of the pressure applied by the force applying plate (22) to the grinding wheel (12) according to the value of the pressure sensor of the grinding wheel (12) displayed on the display; S3, reading the value of the oil film pressure sensor (5) on the display, and adjusting the thickness of the film (11) outside the oil chamber according to the value of the oil film pressure sensor (5); S4, driving the main shaft body (10) to rotate, and applying the same pressure as S2 to the rotating grinding wheel (12), and measuring the offset of the main shaft (1) through the micrometer (3) in contact with the main shaft body (10); S5. Adjust the amount of oil in the corresponding oil chamber according to the offset of the main shaft body (10), and repeat step S4 until the offset of the main shaft body (10) is at an appropriate value.

7. A method for detecting the rigidity of a spindle of a CNC grinding machine according to claim 6, characterized in that: A suitable value of the offset of the spindle (1) in step S5 is 0.001 mm.

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