A direct-connected spindle structure for high-precision machine tools

Abstract

The present invention relates to the technical field related to spindles, and discloses a direct-connected spindle structure for a high-precision machine tool. In the present invention, a driving gallows is arranged between the spindle and a fixed sleeve, and the driving gallows follows the rotation of the spindle. Therefore, when the spindle rotates, the driving gallows causes the lubricating oil to circulate in the oil storage chamber and the movable groove by rotation, which not only lubricates the bearings with the oil, but also takes away the temperature in the spindle with the lubricating oil, thereby reducing the temperature of the spindle. At the same time, since the driving gallows is provided with multiple turns of screw channels, the residence time of the lubricating oil in the driving gallows is increased, the heat reduction rate is increased, and finally the purpose of circulating cooling and real-time lubrication is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field related to spindles, and in particular to a direct-connected spindle structure for high-precision machine tools. Background Art

[0002] High-precision direct-coupled spindle boxes are generally used in machining centers. They do not use belt drive. Due to technical requirements, they are now basically directly connected to the tail of the spindle through a rigid coupling.

[0003] Although the direct-connected spindle has strong rigidity, the temperature will be transmitted faster due to the direct rigid connection, causing the spindle to be in a high temperature state for a long time, resulting in a shortened service life; on the other hand, in order to prevent external dust and the like from corroding the bearings, a sealing ring will be placed between the spindle and the fixed sleeve, but the outer side of the sealing ring will aggravate the wear of the fixed sleeve on the sealing ring due to the continuous rotation of the spindle, thereby causing insufficient sealing and reducing the performance and service life of the spindle bearings. Summary of the invention

[0004] In view of the shortcomings of the existing direct-coupled spindles mentioned in the background technology during use, the present invention provides a direct-coupled spindle structure for high-precision machine tools, which has the advantages of cyclic cooling and real-time lubrication, and solves the technical problems mentioned in the above background technology.

[0005] The present invention provides the following technical solutions: a direct-connected spindle structure for a high-precision machine tool, comprising a spindle and a fixed sleeve, the spindle and the fixed sleeve being movably connected via a bearing, and the number of bearings is two, the interior of the fixed sleeve is provided with a movable groove running through the middle, and the bearing is located in the movable groove, the side wall of the spindle is fixedly installed with a driving gallows located between the bearings, the outer side of the driving gallows is provided with a threaded groove, and the number of turns of the threaded groove is at least seven, the inner wall of the fixed sleeve is provided with an oil storage cavity for storing lubricating oil, and the side wall of the fixed sleeve is provided with an oil filling plug for injecting oil into the oil storage cavity, the side walls of the spindle are respectively provided with sealing retaining rings located on one side of the bearing, and the bearing is located in the sealed movable groove, the inner wall of the fixed sleeve is provided with an oil delivery channel communicating with the sealed movable groove, and the number of oil delivery channels is two, and the oil delivery channel is placed between the sealing retaining ring and the bearing.

[0006] Preferably, a flexible retaining ring is fixedly installed on the outer side of the sealing retaining ring, and a sealing retaining ring slidably connected to the inner wall of the fixed sleeve is fixedly installed on the outer side of the flexible retaining ring. The inner wall of the fixed sleeve is provided with a sealing groove for the movement of the flexible retaining ring, and the cross-sectional shape of the sealing groove is an isosceles trapezoid. The sealing retaining ring is movably sleeved with the main shaft.

[0007] Preferably, a side wall of the main shaft is provided with an annular groove which is sleeved with the sealing retaining ring, and the shape of the annular groove is elliptical.

[0008] Preferably, an adjusting rod is slidably connected to the inner wall of the fixed sleeve, and both ends of the adjusting rod are movably connected to two sealing retaining rings respectively, and a flow isolation hole is opened on the side wall of the flow isolation hole for realizing the connection and disconnection between the oil delivery channel and the movable groove.

[0009] Preferably, the number of the isolation holes is four, two of the isolation holes form a group, and one group of isolation holes is located on both sides of the oil delivery channel. When the sealing retaining ring is separated from the fixed sleeve, the isolation holes are connected to the oil delivery channel.

[0010] The present invention has the following beneficial effects:

[0011] 1. The present invention provides a driving gallows between the main shaft and the fixed sleeve. The driving gallows follows the rotation of the main shaft. When the main shaft rotates, the driving gallows rotates to circulate the lubricating oil in the oil storage chamber and the movable groove. The bearing is not only lubricated by the oil, but also the temperature in the main shaft is taken away by the lubricating oil to reduce the temperature of the main shaft. At the same time, since the driving gallows is provided with multiple turns of screws, the residence time of the lubricating oil in the driving gallows is increased, the heat reduction rate is increased, and finally the purpose of circulating cooling and real-time lubrication is achieved.

[0012] 2. The present invention provides a flexible retaining ring on the outer side of the sealing retaining ring, and a sealing retaining ring on the top of the flexible retaining ring, thereby ensuring that in actual use, the lubricating oil is pressurized during the process of driving the gallows to rotate, forcing the sealing retaining ring to slide in the main shaft, and sealing is performed through the synchronous action of the flexible retaining ring and the sealing retaining ring. When the sealing retaining ring is continuously pushed, the side wall of the flexible retaining ring will fit against the inner wall of the fixed sleeve. At this time, the sealing retaining ring is separated from the inner wall of the fixed sleeve, so that the sealing of the movable groove and the outer side is guaranteed only by the sliding of the flexible retaining ring and the inner wall of the fixed sleeve, that is, by wearing the thickness of the flexible retaining ring, the pressure ejected by the driving gallows is pushed into the side wall of the fixed sleeve in real time after it is worn, thereby realizing wear compensation, and finally achieving the purpose of enhancing the sealing strength and wear compensation.

[0013] 3. The present invention arranges an adjusting rod in the fixed sleeve, and connects the two ends of the adjusting rod with the sealing retaining rings respectively, so as to ensure that during the cooling process, the two sealing retaining rings will be prompted to move synchronously according to the adjusting rod, and a flow isolation hole is opened on the side wall of the adjusting rod, so as to ensure that the two flexible retaining rings are in contact with the fixed sleeve before the lubricating oil circulation in the oil storage chamber and the movable groove can be realized. On the one hand, the flexible retaining ring can adaptively adjust the sealing position following the change of the flow direction of the lubricating oil, and on the other hand, it avoids the pressure generated by the lubricating oil from being output from the oil delivery channel, resulting in a reduction in the pushing strength of the sealing retaining ring, causing the sealing retaining ring and the inner wall of the fixed sleeve to wear, resulting in the sealing retaining ring being unable to compensate for the wear and causing a poor seal, thereby ultimately achieving the purpose of synchronous sealing and adaptive adjustment of the sealing position. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the overall three-dimensional structure of the present invention;

[0015] Figure 2 It is a schematic diagram of the overall internal three-dimensional structure of the present invention;

[0016] Figure 3 It is a schematic diagram of the overall cross-sectional structure of the present invention;

[0017] Figure 4 It is a schematic diagram of the sealing retaining ring structure of the present invention.

[0018] In the figure: 1. main shaft; 2. fixed sleeve; 3. bearing; 4. sealing retaining ring; 5. driving gallows; 6. oil storage chamber; 7. oil filling plug; 8. adjusting rod; 9. flow isolation hole; 10. oil delivery channel; 11. sealing retaining ring; 12. flexible retaining ring; 13. movable groove. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] See also Figure 1 and Figure 2A direct-connected spindle structure for a high-precision machine tool comprises a spindle 1 and a fixed sleeve 2, which are movably connected to the spindle 1 and the fixed sleeve 2 via a bearing 3, and the number of the bearings 3 is two, and a movable groove 13 penetrating the middle is opened inside the fixed sleeve 2, and the bearing 3 is located in the movable groove 13, and a driving gallows 5 located between the bearings 3 is fixedly installed on the side wall of the spindle 1, and a thread groove is opened on the outer side of the driving gallows 5, and the number of turns of the thread groove is at least seven, and an oil storage cavity 6 for storing lubricating oil is opened on the inner wall of the fixed sleeve 2, and an oil filling plug 7 for injecting oil into the oil storage cavity 6 is provided on the side wall of the fixed sleeve 2, and a sealing retainer 4 is respectively provided on the side wall of the spindle 1 on one side of the bearing 3, and the movable groove 13 inside the fixed sleeve 2 is sealed by the sealing retainer 4, and the bearing 3 is located in the sealed movable groove 13, and The inner wall of the fixed sleeve 2 is provided with an oil delivery channel 10 which is communicated with the sealing movable groove 13, and there are two oil delivery channels 10, which are placed between the sealing retaining ring 4 and the bearing 3, so as to ensure that in the actual working process, the driving gallows 5 is rotated following the main shaft 1, so that the lubrication in the movable groove 13 is forced to circulate between the movable groove 13, the oil delivery channel 10 and the oil storage chamber 6 when the driving gallows 5 rotates, on the one hand, the temperature of the main shaft 1 is reduced, and on the other hand, the bearing 3 is lubricated in real time by the oil, and the bearing 3 is cooled synchronously. At the same time, the driving gallows 5 will change the rotation direction of the main shaft 1 so that the flow direction of the lubricating oil in the movable groove 13 is changed, and the driving gallows 5 is provided with multiple spiral grooves, thereby increasing the time that the lubricating oil stays in the driving gallows 5, that is, greatly enhancing the intensity of the temperature output to the outside of the main shaft 1.

[0021] See also Figure 3In order to prevent the outer side of the sealing retaining ring 4 from being worn by continuous sliding with the inner wall of the fixed sleeve 2, thereby causing the phenomenon of poor sealing, a flexible retaining ring 12 is fixedly installed on the outer side of the sealing retaining ring 4, and a sealing retaining ring 11 slidably connected to the inner wall of the fixed sleeve 2 is fixedly installed on the outer side of the flexible retaining ring 12. At the same time, a sealing groove for the movement of the flexible retaining ring 12 is opened on the inner wall of the fixed sleeve 2, and the cross-sectional shape of the sealing groove is an isosceles trapezoid. The sealing retaining ring 4 is movably sleeved with the main shaft 1, thereby ensuring that the lubricating oil impact generated by the driving gallows 5 during the rotation process causes the sealing retaining ring 4 to slide in the side wall of the main shaft 1, and the lubricating oil The impact of the lubricating oil forces the flexible retaining ring 12 to fit onto the inclined surface of the sealing groove, forcing the sealing retaining ring 11 to separate from the fixed shaft sleeve 2, ensuring that the side wall of the flexible retaining ring 12 is always in sliding connection with the inner wall of the fixed shaft sleeve 2 during the process of following the rotation of the main shaft 1, and the liquid pressure applied by driving the gallows 5 to rotate acts on the flexible retaining ring 12 at the same time, ensuring the sealing while allowing the flexible retaining ring 12 to compensate for the wear autonomously under the pressure after wear, thereby ensuring the sealing performance. The sealing retaining ring 11 will only contact the inner wall of the fixed shaft sleeve 2 to form a seal when the sealing retaining ring 4 slides on the main shaft 1, thereby ensuring the sealing during switching.

[0022] See also Figure 3 and Figure 4 In order to make the sealing ring 4 only slide on the main shaft 1 and rotate with the main shaft 1, a ring groove that is sleeved with the sealing ring 4 is opened on the side wall of the main shaft 1, and the shape of the ring groove is elliptical, so as to ensure that the sealing ring 4 transmits torque while sliding on the main shaft 1, and the setting of the ring groove ensures that when the sealing ring 4 is attached to the main shaft 1, the side wall of the sealing ring 4 is attached, thereby further ensuring its sealing performance.

[0023] See also Figure 2 and Figure 3 In order to prevent a large amount of oil from flowing back from the oil delivery channel 10 when the driving gallows 5 gathers the hydraulic oil in the movable groove 13, thereby making the sealing retaining ring 4 unable to move normally, an adjusting rod 8 is slidably connected to the inner wall of the fixed sleeve 2, and the two ends of the adjusting rod 8 are movably connected to the two sealing retaining rings 4 respectively, and a flow isolation hole 9 for realizing the connection and disconnection between the oil delivery channel 10 and the movable groove 13 is opened on the side wall of the flow isolation hole 9, so as to ensure that in the actual use process, after the driving gallows 5 applies pressure to one sealing retaining ring 4 through the lubricating oil, the two sealing retaining rings 4 will be synchronized through the adjusting rod 8 to ensure the stability of the seal and avoid the phenomenon of oil leakage caused by a single loose seal.

[0024] See also Figure 3In order to ensure that the oil delivery channel 10 and the movable groove 13 are connected during the left and right movement of the sealing retaining ring 4, the number of the isolation holes 9 is set to four, two isolation holes 9 form a group, and one group of isolation holes 9 is located on both sides of the oil delivery channel 10. When the sealing retaining ring 11 is separated from the fixed sleeve 2, the isolation holes 9 are connected to the oil delivery channel 10, thereby ensuring that in actual use, the oil delivery channel 10 and the isolation holes 9 can be opened only when the flexible retaining ring 12 is in a sealed position, that is, it is ensured that there is sufficient oil pressure in the movable groove 13 to achieve the sealing of the flexible retaining ring 12.

[0025] The working principle of the present invention is as follows: a sufficient amount of lubricating oil is injected into the oil storage chamber 6 through the oil injection plug 7. At this time, the movable groove 13 located between the sealing retaining rings 4 also contains lubricating oil. Then, the main shaft 1 rotates to work.

[0026] in accordance with Figure 3 When the main shaft 1 rotates forward, it will drive the driving gallows 5 to rotate in the same way. The rotation of the driving gallows 5 will force the lubricating oil in the movable groove 13 to be transported from the right side of the driving gallows 5 to the left side of the driving gallows 5, and the lubricating oil has a certain residence time in the driving gallows 5, so that it is easier to absorb the high temperature in the main shaft 1. At the same time, the driving gallows 5 increases the contact area with the lubricating oil, further enhancing the cooling rate. Secondly, the hydraulic oil pressure on the left side of the driving gallows 5 is enhanced, which will push the sealing retaining ring 4 on the left side to move leftward. During the activity of the sealing retaining ring 4, the outer side of the sealing retaining ring 11 is slidably connected to the inner wall of the fixed shaft sleeve 2, and the sealing retaining ring 4 is continuously pushed until the side wall of the flexible retaining ring 12 is attached to the inside of the fixed shaft sleeve 2. At this time, the sealing retaining ring 4 is continuously subjected to the pressure of the lubricating oil, causing the flexible retaining ring 12 to continue to move to the left. Before, until the sealing retaining ring 11 is no longer in contact with the inner wall of the fixed sleeve 2, the flexible retaining ring 12 follows the movement of the main shaft 1 and its side wall slides relative to the inner wall of the fixed sleeve 2 to form a seal. At the same time, when the sealing retaining ring 4 on the left side moves to the left, it will synchronously pull the adjusting rod 8, causing the sealing retaining ring 4 on the right side to move to the left synchronously, causing the left side wall of the right flexible retaining ring 12 to slide with the inner wall of the fixed sleeve 2 to form a seal. As the flexible retaining ring 12 continues to move to the left, it will force the isolation hole 9 to gradually approach the oil delivery channel 10, causing the oil delivery channel 10 to communicate with the isolation hole 9, and the oil storage chamber 6 and the movable groove 13 are connected through the oil delivery channel 10, and the gallows 5 is driven to rotate to force the lubricating oil to circulate between the oil storage chamber 6 and the movable groove 13 for cooling, and when the lubricating oil flows, it acts on the bearing 3 to cool it down and lubricate it in real time.

[0027] Similarly, when the main shaft 1 rotates in the reverse direction, it will force the driving gallows 5 to pressurize the lubricating oil to the right, causing the sealing ring 4 to move to the right, thereby finally realizing the circulation of the lubricating oil.

[0028] Finally, when the main shaft 1 stops, the elastic recovery of the flexible retaining ring 12 forces the flow isolation hole 9 to move away from the oil delivery channel 10, so that the oil storage chamber 6 and the movable groove 13 are blocked again, so that the sealing position of the flexible retaining ring 12 can be quickly switched by changing the rotation direction during the next rotation of the main shaft 1.

[0029] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0030] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A direct-connected spindle structure for a high-precision machine tool, comprising a spindle (1) and a fixed sleeve (2), characterized in that: The main shaft (1) and the fixed shaft sleeve (2) are movably connected via a bearing (3), and the number of the bearings (3) is two. The fixed shaft sleeve (2) is provided with a movable groove (13) running through the middle, and the bearing (3) is located in the movable groove (13). A driving gallows (5) located between the bearings (3) is fixedly mounted on the side wall of the main shaft (1). The driving gallows (5) is provided with a thread groove on the outside, and the number of turns of the thread groove is at least seven. The inner wall of the fixed shaft sleeve (2) is provided with a groove for storing lubricating oil. An oil storage cavity (6) is formed, and the side wall of the fixed sleeve (2) is provided with an oil filling plug (7) for injecting oil into the oil storage cavity (6); the side walls of the main shaft (1) are respectively provided with sealing retaining rings (4) located on one side of the bearing (3); the bearing (3) is located in a sealed movable groove (13); the inner wall of the fixed sleeve (2) is provided with an oil delivery channel (10) communicating with the sealed movable groove (13); the number of the oil delivery channels (10) is two, and the oil delivery channels (10) are located between the sealing retaining ring (4) and the bearing (3); A flexible retaining ring (12) is fixedly mounted on the outer side of the sealing retaining ring (4), and a sealing retaining ring (11) slidably connected to the inner wall of the fixed shaft sleeve (2) is fixedly mounted on the outer side of the flexible retaining ring (12); a sealing groove for movement of the flexible retaining ring (12) is formed on the inner wall of the fixed shaft sleeve (2), and the cross-sectional shape of the sealing groove is an isosceles trapezoid; the sealing retaining ring (4) is movably sleeved with the main shaft (1); The inner wall of the fixed shaft sleeve (2) is slidably connected to an adjusting rod (8), and the two ends of the adjusting rod (8) are movably connected to two sealing retaining rings (4) respectively. The side wall of the adjusting rod (8) is provided with a flow isolation hole (9) for realizing the connection and disconnection between the oil delivery channel (10) and the movable groove (13).

2. The direct-connected spindle structure for a high-precision machine tool according to claim 1, characterized in that: The side wall of the main shaft (1) is provided with an annular groove sleeved with the sealing retaining ring (4), and the shape of the annular groove is elliptical.

3. The direct-connected spindle structure for a high-precision machine tool according to claim 1, characterized in that: The number of the isolation holes (9) is four, two of the isolation holes (9) form a group, and one group of isolation holes (9) is located on both sides of the oil delivery channel (10). When the sealing retaining ring (11) is separated from the fixed shaft sleeve (2), the isolation holes (9) are connected to the oil delivery channel (10).

Images