Novel superspeed grinding wheel box spindle structure

Abstract

The invention relates to a novel superspeed grinding wheel box spindle structure, and relates to the field of precision machining technology, the novel superspeed grinding wheel box spindle structure comprises a box body, a grinding wheel spindle, a bearing system and a grinding wheel positioning mechanism, the bearing system is integrated with a hybrid bearing, and stable and reliable axial positioning and pre-tightening are provided for the grinding wheel spindle through a fixing sleeve, a pre-tightening spring and a bearing sleeve; and the influence of thermal expansion and cold contraction of the grinding wheel spindle is avoided, and axial locking of the grinding wheel spindle due to abnormal temperature rise can be effectively prevented. The grinding wheel positioning mechanism comprises an elastic positioning sleeve, a compression nut and a fastening screw, automatic centering of the superhard grinding wheel in the mounting and fixing process can be achieved, and the high-rigidity and high-coaxiality clamping effect is achieved. The mounting and positioning precision and reliability of the grinding wheel under the ultra-high-speed working condition can be improved, and the long-term operation stability and machining quality of the grinding wheel spindle are guaranteed.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of precision machining technology, and in particular to a novel super-high-speed grinding wheel box spindle structure. BACKGROUND

[0002] In modern manufacturing, with the increasing demand for part machining precision, surface quality and machining efficiency, super-high-speed grinding technology has become an important development direction in the field of precision and ultra-precision machining. The super-high-speed grinding process represented by cubic boron nitride (CBN) grinding wheel is widely used in aerospace, high-performance automobile parts manufacturing, precision mold and other industries with strict requirements on part quality, due to its high grinding efficiency, stable machining precision, excellent workpiece surface quality and good comprehensive economy.

[0003] In the prior art, when the grinding wheel linear speed exceeds a certain value, in order to resist the huge centrifugal force and prevent the base from breaking and causing accidents, a grinding wheel base made of special material is usually used, and a layer of super-hard abrasive layer is bonded on the base.

[0004] Under the condition of continuous super-high-speed operation, the heat dissipation problem of the spindle system is particularly prominent. At present, the industry generally uses oil cooling to control the temperature rise of the spindle, that is, through circulating cooling oil to forcibly take away the large amount of heat generated in the spindle, especially in the bearing area, due to friction and aerodynamic effect.

[0005] In view of the above, under the condition of continuous super-high-speed operation of the spindle, if the cooling system does not cool in time, the temperature of the spindle will rise significantly, which will cause the change of the clearance between the spindle and the bearing, the decline of the lubrication and cooling performance, and the acceleration of the bearing failure. In extreme cases, it may cause "shaft holding" accidents, that is, the adhesion, wear and even welding between the spindle and the bearing due to overheating, causing the equipment to be stuck and stopped, which seriously affects the service life and operation reliability of the spindle. SUMMARY

[0006] In order to improve the operation reliability of the super-high-speed grinding wheel spindle under high-speed operation, the present application provides a novel super-high-speed grinding wheel box spindle structure.

[0007] The present application provides a novel super-high-speed grinding wheel box spindle structure, which adopts the following technical scheme: The novel ultra-high-speed grinding wheel box spindle structure comprises a box body, a grinding wheel spindle and a bearing system, the grinding wheel spindle is rotatably installed in the box body, and the grinding wheel spindle is provided with a first protruding portion at one end close to the grinding wheel installation position; the bearing system comprises a fixing sleeve, pre-tightening springs, locking screws and a bearing sleeve, the fixing sleeve is fixedly installed on the grinding wheel spindle through a plurality of locking screws, and the fixing sleeve is located at one end of the grinding wheel spindle away from the first protruding portion; the bearing sleeve is provided with a second protruding portion, the bearing sleeve is coaxially and slidingly arranged on the grinding wheel spindle, and a plurality of pre-tightening springs are fixedly arranged between the fixing sleeve and the bearing sleeve; one end of the pre-tightening spring abuts against the second protruding portion, and the other end abuts against the fixing sleeve.

[0008] Preferably, the bearing system further comprises a tight-pear bearing, an inner hole of the tight-pear bearing is sleeved on the grinding wheel spindle, and an outer peripheral surface of the tight-pear bearing is sleeved in an inner hole of the bearing sleeve.

[0009] Preferably, an outer periphery of the grinding wheel spindle in the axial direction is sequentially provided with a positioning conical surface and a positioning end surface; the grinding wheel positioning mechanism comprises an elastic positioning sleeve, fastening screws and a pressing nut, an inner hole of the elastic positioning sleeve is conical; a plurality of elastic openings are formed in the circumferential direction of the elastic positioning sleeve, and opening directions of adjacent two elastic openings are opposite; the pressing nut is threadedly connected with the grinding wheel spindle, one end of the pressing nut abuts against the elastic positioning sleeve, and an outer diameter of the elastic positioning sleeve abuts against an inner diameter of the grinding wheel; a plurality of fastening screws are fixedly connected with the positioning end surface of the grinding wheel spindle, and the grinding wheel is fixed on the grinding wheel spindle through the fastening screws.

[0010] Preferably, the bearing system further comprises two dynamic and static pressure bearings, the two dynamic and static pressure bearings are oppositely arranged, an inner hole of one of the dynamic and static pressure bearings is sleeved on the grinding wheel spindle, and an outer peripheral surface thereof is fixedly connected with an inner wall of the box body; an inner hole of the other dynamic and static pressure bearing is sleeved on the bearing sleeve, and an outer peripheral surface thereof is fixedly connected with the inner wall of the box body; and an oil passage in the dynamic and static pressure bearing is in communication with an oil supply system.

[0011] Preferably, a radial oil cavity is formed in the inner hole of the dynamic and static pressure bearing, and an end surface oil cavity is formed in one side end surface of the dynamic and static pressure bearing; the end surface oil cavity of one of the dynamic and static pressure bearings acts on the first protruding portion, and the end surface oil cavity of the other dynamic and static pressure bearing acts on the second protruding portion.

[0012] Preferably, a plurality of first oil inlet pipes and a plurality of second oil inlet pipes are further installed on the box body, the first oil inlet pipes are communicated with the radial oil cavities, and the second oil inlet pipes are communicated with the end face oil cavities; an oil return cavity is further formed in the inner hole of the dynamic-static pressure bearing, and the first oil inlet pipes, the second oil inlet pipes and the oil return cavity are all communicated with the oil supply system.

[0013] Preferably, a thermostat device is further connected to the oil circuit between the dynamic-static pressure bearing and the oil supply system, and the thermostat device is used for temperature regulation of the hydraulic oil of the oil supply system.

[0014] Preferably, a driving mechanism is further arranged on the box body, the driving mechanism comprises a first pulley, a second pulley, a driving motor and a transmission belt, the first pulley is coaxially fixedly connected with the grinding wheel spindle, the driving motor is fixedly installed on the box body, the second pulley is fixedly installed on the output shaft of the driving motor, and the transmission belt is sleeved on the first pulley and the second pulley.

[0015] Preferably, a mounting taper is formed at the end of the grinding wheel spindle away from the first protruding part, the inner hole of the first pulley is a tapered hole, the first pulley is fixed with the grinding wheel spindle through the mounting taper, a dismounting cavity is formed in the inner hole of the first pulley, a plurality of oil through holes are formed in the end face of the first pulley, and the oil through holes are communicated with the dismounting cavity.

[0016] Preferably, an air inlet and an air circulation loop are formed in the box body, a sealing cover is fixedly installed on the box body, an air passage is formed in the sealing cover, the air inlet and the air circulation loop are communicated with the air passage, and a dustproof ring is installed on the sealing cover.

[0017] In summary, the present application has at least one of the following beneficial technical effects: 1. The bearing system can automatically compensate the thermal expansion of the grinding wheel spindle and the bearing system caused by high-speed operation, so that the grinding wheel spindle is allowed to have a certain amount of expansion in the axial direction, the bearing axial gap is prevented from being too small or too large due to thermal expansion and cold contraction, the shaft seizure accident or precision loss is prevented, and the thermal stability is significantly improved.

[0018] 2. The pre-tightening spring can provide continuous and stable axial pre-tightening force for the bearing system, can eliminate the axial gap error, can inhibit the axial movement of the main shaft, can ensure the axial positioning accuracy of the main shaft, and can enhance the axial stiffness and the retention of the accuracy, so that the axial stiffness and the retention of the accuracy are almost not affected by temperature changes.

[0019] 3. The inner conical hole of the elastic positioning sleeve and the conical surface at the left end of the grinding wheel spindle form a sliding fit. During the tightening of the clamping nut, the outer circle of the elastic positioning sleeve gradually expands as the inner hole wall slides to the right, and forms a tight fit with the inner hole of the grinding wheel. This makes the right end face of the grinding wheel and the positioning end face of the grinding wheel on the grinding wheel spindle fit tightly together. At this time, the end face and the inner hole provide common support, which greatly enhances the connection rigidity of the grinding wheel. Moreover, this structure can be repeatedly disassembled and reinstalled with high accuracy.

[0020] 4. The elastic positioning sleeve improves the centering accuracy of the grinding wheel installation, which greatly reduces the eccentricity and error of the grinding wheel installation. This not only reduces the vibration caused by the eccentricity of the installation, but also greatly reduces the amount of dressing required for the grinding wheel abrasive layer before it is put into use. To a certain extent, this reduces the wear of the abrasive layer, saves costs, and reduces the time for correction and adjustment.

[0021] 5. Utilize the gap between the bearing sleeve and the fixed sleeve to maintain elastic support under the action of the preload spring; when the grinding wheel is subjected to a large axial force, see the instruction manual appendix. Figure 1 As shown, if the axial force is to the left, causing the grinding wheel spindle to shift axially to the left by a certain amount, the gap can continue to be compressed. During this process, a greater reverse resistance will be generated, which also provides the spindle system with more time to make necessary adjustments, achieve the effect of active protection, and further enhance the reliability of the bearing system. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the overall structure of an embodiment of the present invention; Figure 2 yes Figure 1 A schematic diagram of the structure of part A; Figure 3 yes Figure 2 A schematic diagram of the upper and middle sections; Figure 4 yes Figure 2 A schematic diagram of the lower half of the structure; Figure 5 yes Figure 1 A structural diagram of section B; Figure 6 This is a schematic diagram of the structure of the grinding wheel spindle and the grinding wheel according to an embodiment of the present invention; Figure 7 It is a cross-sectional and three-dimensional structural diagram of the elastic positioning sleeve; Figure 8 This is a schematic diagram of the structure of the ball bearing and the retaining sleeve in an embodiment of the present invention; Figure 9 This is a schematic diagram of the bearing sleeve according to an embodiment of the present invention; Figure 10 This is a schematic diagram of the connection status of the oil supply system according to an embodiment of the present invention; Figure 11 is a schematic view of the full-automatic balancing instrument and the belt protection cover added by the embodiment of the present application.

[0023] The label of the drawing is explained: 100, box; 110, box cover; 200, grinding wheel spindle; 210, first protruding part; 220, positioning conical surface; 230, positioning end surface; 300, grinding wheel positioning mechanism; 310, elastic positioning sleeve; 320, fastening screw; 330, pressing nut; 340, elastic port; 350, dismounting screw; 400, bearing system; 410, dynamic and static pressure bearing; 421, radial oil cavity; 422, end surface oil cavity; 423, first oil inlet pipe; 424, second oil inlet pipe; 425, oil return cavity; 430, oil supply system; 431, constant temperature device; 432, oil supply pipe; 440, tight bead bearing; 450, fixing sleeve; 460, pre-tightening spring; 470, bearing sleeve; 471, second protruding part; 480, locking screw; 500, driving mechanism; 510, first belt pulley; 520, second belt pulley; 530, driving motor; 540, transmission belt; 560, mounting conical surface; 570, dismounting cavity; 580, oil passage; 600, grinding wheel; 710, air inlet; 720, air passage; 730, air vent groove; 740, dustproof ring; 750, sealing cover; 800, full-automatic balancing instrument; 900, belt protection cover. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings Figure 1 to the drawings Figure 11 , the technical solutions in the embodiments of the present application are clearly and completely described. Obviously, the described embodiments are only part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor belong to the scope of protection of the present application.

[0025] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present application are only used to explain the relative position relationship, movement condition, etc. between the components in a certain posture (as shown in the drawings), if the certain posture changes, the directional indications also change accordingly.

[0026] In addition, the description such as "first", "second" and the like in the present application is only for the purpose of description, and cannot be understood as indicating or implying the relative importance of the indicated technical features or implicitly indicating the number of the indicated technical features. Therefore, the features limited by "first", "second" can be explicitly or implicitly included at least one of the features. In the description of the present application, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise specifically limited.

[0027] In the present application, unless otherwise explicitly specified and limited, the terms "connection", "fixing" and the like should be understood in a broad sense, for example, "fixing" can be fixed connection, or detachable connection, or integral; can be mechanical connection, or electromagnetic connection; can be directly connected, or indirectly connected through an intermediate medium, can be the internal communication of two elements or the interaction relationship of two elements, unless otherwise explicitly limited. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0028] In addition, the technical solutions of various embodiments of the present application can be combined with each other, but it must be based on the fact that a person skilled in the art can realize it, when the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of technical solutions does not exist, nor within the protection scope required by the present application.

[0029] The embodiment of the present application discloses a new type of ultra-high-speed grinding wheel box spindle structure. Referring to Figures 1 to 11 A new type of ultra-high-speed grinding wheel box spindle structure mainly includes a box body 100, a grinding wheel spindle 200 and a bearing system 400, the grinding wheel spindle 200 is rotatably installed in the box body 100, and the grinding wheel spindle 200 is provided with a first protruding part 210 at one end close to the installation position of the grinding wheel 600; the bearing system 400 includes a fixing sleeve 450, a pre-tightening spring 460, a locking screw 480 and a bearing sleeve 470, the fixing sleeve 450 is fixedly installed on the grinding wheel spindle 200 through a plurality of locking screws 480, and the fixing sleeve 450 is located at one end of the grinding wheel spindle 200 away from the first protruding part 210; the bearing sleeve 470 is provided with a second protruding part 471, the bearing sleeve 470 is coaxially and slidingly arranged on the grinding wheel spindle 200, and the bearing sleeve 470 can slide in the axial direction of the grinding wheel spindle 200 within a small range; a plurality of pre-tightening springs 460 are fixedly arranged between the fixing sleeve 450 and the bearing sleeve 470, one end of the pre-tightening spring 460 abuts against the second protruding part 471, and the other end of the pre-tightening spring 460 abuts against the fixing sleeve 450, and the upper end of the box body 100 is fixedly installed with a box cover 110.

[0030] The pre-tightening spring 460 can automatically compensate for the thermal expansion difference of the grinding wheel spindle 200 and the bearing system 400 caused by high-speed operation, so that the grinding wheel spindle 200 is allowed to have a certain displacement in the axial direction, avoids the bearing axial gap being too small due to thermal elongation, prevents the occurrence of shaft holding accidents, maintains a certain rotation accuracy and improves thermal stability. The pre-tightening spring 460 provides stable and automatically compensating axial pre-tightening force, can effectively inhibit the excessive axial movement of the spindle, improve the axial stiffness and rotation accuracy. The elastic pre-tightening mode reduces the hard impact and stress concentration, protects the precise bearing components, prolongs the service life of the entire bearing system 400 and improves the operation reliability of the ultra-high-speed grinding wheel spindle 200 under high-speed operation.

[0031] When the fixing sleeve 450 is fixed to the grinding wheel spindle 200 by the locking screws 480, the locking screws 480 uniformly distributed in the circumferential direction are tightly abutted against the grinding wheel spindle 200, so that the fixing sleeve 450 as a whole is elastically deformed into a regular polygon, and the circumferential embracing fastening effect is achieved after the deformation, so that the fixing sleeve 450 is firmly fixed to the grinding wheel spindle 200; when all the locking screws 480 are loosened, the elastic deformation is restored, and a gap of 0.01 to 0.02 mm is formed between the inner hole of the fixing sleeve 450 and the grinding wheel spindle 200, so that the fixing sleeve 450 can be axially moved, facilitating the assembly and adjustment of the fixing sleeve 450.

[0032] Referring to Figure 1 , Figure 2 , Figure 3 , Figure 4 and Figure 8 , in some embodiments, the bearing system 400 further comprises a tight ball bearing 440, the inner hole of the tight ball bearing 440 is sleeved on the grinding wheel spindle 200, and the outer circumferential surface of the tight ball bearing 440 is sleeved in the bearing sleeve 470. The tight ball bearing 440 includes but is not limited to hundreds of precision grade steel balls with consistent diameters, which are uniformly and regularly arranged in a copper sleeve, and the copper sleeve has hundreds of small holes, the bottom of each small hole is slightly smaller and can just accommodate a steel ball without passing through. The steel ball can roll in the small hole, and the outer edge of the small hole is uniformly extruded to prevent the steel ball from falling out.

[0033] The inner hole of the bearing sleeve 470 is uniformly and consistently ground with the gap between the right side shaft diameter of the grinding wheel spindle 200, and the gap can just accommodate a set of tight ball bearings 440. A slight elastic deformation of 2 to 4 microns is required in the actual installation process, and the elastic deformation of the hundreds of steel balls can eliminate the gap between the grinding wheel spindle 200 and the bearing sleeve 470 and form a certain degree of interference fit to provide better stable support. When the bearing sleeve 470 is axially displaced, the steel balls of the tight ball bearing 440 will roll with it, realizing the axial displacement of the bearing sleeve 470 on the grinding wheel spindle 200 under the condition that there is almost no gap, and the displacement is generally not more than 1 mm. The rotation amplitude of the steel balls in the tight ball bearing 440 is very small, and the axial displacement is very stable, highly precise, and the service life of the tight ball bearing 440 is extremely long.

[0034] The pre-tightening spring 460 can provide continuous and stable axial pre-tightening force, improve the axial stiffness and precision retention of the grinding wheel spindle 200, compensate for the thermal expansion of the grinding wheel spindle 200 due to temperature rise, avoid the situation that the bearing is stuck due to thermal stress, and further absorb axial vibration.

[0035] Referring to Figure 5 , Figure 6 and Figure 7In some embodiments, the grinding wheel spindle 200 has a positioning taper surface 220 and a positioning end surface 230 successively formed on the outer periphery in the axial direction; and a grinding wheel positioning mechanism 300 is further included, which comprises an elastic positioning sleeve 310, fastening screws 320 and a compression nut 330. The inner hole of the elastic positioning sleeve 310 is a tapered hole, which is in taper fit with the positioning taper surface 220. A plurality of elastic openings 340 are formed on the elastic positioning sleeve 310 in the circumferential direction, and the opening directions of adjacent two elastic openings 340 are opposite. The compression nut 330 is threadedly connected with the left end of the grinding wheel spindle 200, and one end of the compression nut 330 abuts against the elastic positioning sleeve 310, and the outer diameter of the elastic positioning sleeve 310 abuts against the inner diameter of the grinding wheel 600. The plurality of fastening screws 320 are fixedly connected with the threaded holes on the positioning end surface 230 of the grinding wheel spindle 200, and the grinding wheel 600 is fixed on the grinding wheel spindle 200 through the fastening screws 320. The number of the elastic openings 340 can be adjusted according to the working conditions.

[0036] The abrasive layer of the grinding wheel 600 is commonly cubic boron nitride or diamond. Due to the huge energy consumption, high equipment investment and high technical threshold in the production process, the cost of raw materials is much higher than that of traditional ordinary abrasives such as corundum and silicon carbide, which is high in cost. After the grinding wheel 600 is installed, the abrasive layer of the grinding wheel 600 needs to be corrected and adjusted before it can be put into production and use.

[0037] When the grinding wheel 600 is installed, the compression nut 330 is gradually screwed onto the grinding wheel spindle 200 by threads, the elastic positioning sleeve 310 is gradually compressed by the compression nut 330 at one end of the grinding wheel spindle 200, the tapered inner hole in the elastic positioning sleeve 310 and the taper at the left end of the grinding wheel spindle 200 form a sliding fit, and as the compression nut 330 is tightened, the outer diameter of the elastic positioning sleeve 310 gradually expands under the action of the taper until it tightly fits the inner hole of the grinding wheel 600, forming an interference fit, thereby completing the automatic centering of the grinding wheel 600. Then, the plurality of fastening screws 320 on the end surface of the grinding wheel 600 are tightened, so that the right end surface of the grinding wheel 600 tightly abuts against the positioning end surface 230 of the grinding wheel 600 on the grinding wheel spindle 200. At this time, the end surface and the inner hole form a common support, greatly enhancing the connection rigidity of the grinding wheel 600, and the structure can be repeatedly disassembled and installed with high precision.

[0038] The above installation process greatly improves the centering accuracy of the grinding wheel 600 installation, greatly reduces the eccentricity and error of the grinding wheel 600 installation, thereby not only reducing the vibration caused by the installation eccentricity, but also greatly reducing the amount of abrasive layer trimming, to a considerable extent, reducing the loss of the abrasive layer, saving the use cost of the equipment, improving the rotation accuracy of the grinding wheel 600 and the utilization rate of the abrasive layer, saving the correction and debugging time in the early stage of use, and at the same time, improving the work efficiency.

[0039] When the grinding wheel 600 needs to be disassembled, the compression nut 330 needs to be loosened first, and then the symmetrical fastening screws 320 are loosened, then two of the fastening screws 320 are removed, and the disassembly screw 350 is screwed into the corresponding hole, so that the head of the disassembly screw 350 abuts against the positioning end face 230, and the disassembly screw 350 is continuously screwed in. Under the action of the abutting force, the elastic positioning sleeve 310 with an interference fit with the inner diameter of the grinding wheel 600 is moved in the disassembly direction by the inner diameter of the grinding wheel 600, so that the elastic positioning sleeve 310 finally separates from the positioning conical surface 220. After the grinding wheel 600 is separated from the positioning end face 230 of the grinding wheel spindle 200, all the fastening screws 320 are finally removed to complete the disassembly of the grinding wheel 600. This set of processes ensures the safety and controllability of the disassembly process, and can maintain the reference accuracy of repeated installation of the grinding wheel spindle 200 and the grinding wheel 600.

[0040] Referring to Figures 1 to 5 In some embodiments, the bearing system 400 further comprises two dynamic-static pressure bearings 410, which are oppositely arranged. The inner hole of one of the dynamic-static pressure bearings 410 is sleeved on the grinding wheel spindle 200, and the outer peripheral surface thereof is fixedly connected with the inner wall of the box body 100. The inner hole of the other dynamic-static pressure bearing 410 is sleeved on the bearing sleeve 470, and the outer peripheral surface thereof is fixedly connected with the inner wall of the box body 100. The oil passage in the dynamic-static pressure bearing 410 is in communication with the oil supply system 430.

[0041] The outer diameter of the bearing sleeve 470 is the same as the outer diameter of the first protruding portion 210 of the grinding wheel spindle 200, and the bearing sleeve 470 and the dynamic-static pressure bearing 410 at the right end of the box body 100 form a liquid sliding fit. The dynamic-static pressure bearing 410 supports the grinding wheel spindle 200 by relying on the dynamic-static pressure oil film formed when rotating at high speed.

[0042] Referring to Figure 2 、 Figure 3 、 Figure 4 、 Figure 5 and Figure 9 In some embodiments, a radial oil cavity 421 is formed on the inner hole of the dynamic-static pressure bearing 410, and an end surface oil cavity 422 is formed on the end surface of one side of the dynamic-static pressure bearing 410. The end surface oil cavity 422 of the dynamic-static pressure bearing 410 on the left side of the grinding wheel spindle 200 acts on the first protruding portion 210, and the end surface oil cavity 422 of the dynamic-static pressure bearing 410 on the right side of the grinding wheel spindle 200 acts on the second protruding portion 471. The end surface oil cavities 422 form static pressure oil films with the first protruding portion 210 and the second protruding portion 471, respectively.

[0043] The end face oil cavity 422 on the two dynamic and static pressure bearings 410 on the left and right sides of the grinding wheel spindle 200 is filled with hydraulic oil, which can form a stable supporting oil film to provide stable bearing capacity. When the grinding wheel 600 bears an axial grinding force to the right, the grinding wheel spindle 200 is axially offset to the right, and the first protruding part 210 of the grinding wheel spindle 200 acts on the end face oil cavity 422 on the dynamic and static pressure bearing 410, causing the oil film pressure at this position to rise, thereby limiting the axial offset of the grinding wheel spindle 200 to the right. Similarly, when the grinding wheel spindle 200 is axially offset to the left, in addition to causing the oil film pressure of the right end face oil cavity 422 to rise, limiting the axial offset of the bearing sleeve 470, the gap between the second protruding part 471 of the bearing sleeve 470 and the fixed sleeve 450 will become smaller, and the pre-tightening spring 460 will be further compressed, thereby providing stronger axial support; ensuring the stability and rigidity of the grinding wheel spindle 200.

[0044] With reference to Figure 2 , Figure 3 , Figure 4 , Figure 5 and Figure 10 In some embodiments, a plurality of first oil inlet pipes 423 and a plurality of second oil inlet pipes 424 are also installed on the box 100, the first oil inlet pipes 423 being in communication with the radial oil cavities 421, and the second oil inlet pipes 424 being in communication with the end face oil cavities 422; the inner hole of the dynamic and static pressure bearing 410 is also provided with a return oil cavity 425, which is in communication with the oil supply system 430 through a return oil pipe, and the first oil inlet pipes 423, the second oil inlet pipes 424 and the oil supply system 430 are in communication through the oil supply pipe 432.

[0045] The external oil supply system 430 is used to input hydraulic oil into the first oil inlet pipes 423 and the second oil inlet pipes 424, so that the end face oil cavities 422 are continuously and stably filled with hydraulic oil. The independent oil inlet path ensures sufficient oil supply and stable pressure of the end face oil cavities 422; the design of the return oil cavity 425 ensures smooth return of the hydraulic oil.

[0046] With reference to Figure 10 In some embodiments, a constant temperature device 431 is also connected to the oil path between the dynamic and static pressure bearing 410 and the oil supply system 430 through the oil supply pipe 432. The constant temperature device 431 is provided with an oil temperature adjusting mechanism and an oil filtering mechanism. The constant temperature device 431 adjusts the temperature of the spindle oil pumped into the grinding wheel spindle 200 by the central pump of the oil supply system 430. The constant temperature device 431 can actively control the temperature of the lubricating oil within the optimal range, solve the problem of heating at high speed, maximize the influence of thermal deformation on machining precision, and at the same time filter impurities in the oil.

[0047] With reference to Figures 1 to 4In some embodiments, the housing 100 is further provided with a drive mechanism 500, which includes a first pulley 510, a second pulley 520, a drive motor 530, and a transmission belt 540. The first pulley 510 is coaxially and fixedly connected to the grinding wheel spindle 200. The drive motor 530 is fixedly mounted on the housing 100, and the second pulley 520 is fixedly mounted on the output shaft of the drive motor 530. The transmission belt 540 is sleeved on the first pulley 510 and the second pulley 520 to form a transmission connection. The diameter of the second pulley 520 may be larger than the diameter of the first pulley 510.

[0048] The drive motor 530 drives the second pulley 520 to rotate, which in turn drives the first pulley 510 to rotate via the transmission belt 540. The first pulley 510 drives the grinding wheel spindle 200 to rotate. This structure can also be equipped with a belt unloading device to avoid the problem of the grinding wheel spindle 200 being deflected or skewed after being subjected to force due to the tension of the transmission belt 540, thereby improving the rotational accuracy of the grinding wheel spindle 200.

[0049] The drive motor 530 can be a permanent magnet synchronous motor, or driven by an electric spindle, or replaced by another external power source to drive the grinding wheel spindle 200 to rotate. The output shaft of the drive motor 530 can have a tapered structure, and a second pulley 520 is mounted on the output shaft. The inner bore of the output shaft pulley and the second pulley 520 are tapered and, after being tightened with screws, form a rotating body with uniform mass. The diameter of the second pulley 520 is different from that of the first pulley 510, thus allowing the motor speed to be adjusted via belt drive. This can increase the output torque of the drive motor 530 by reducing speed, or decrease the speed of the drive motor 530 by increasing speed, which helps extend the life of the bearings inside the drive motor 530. Furthermore, the belt drive prevents vibrations generated during the operation of the drive motor 530 from being transmitted to the grinding wheel spindle 200. Reduced vibration contributes to the smooth rotation of the grinding wheel spindle 200 and extends bearing life, further enhancing the stability of the invention.

[0050] Reference Figure 2 , Figure 3 , Figure 4 and Figure 6In some embodiments, the end of the grinding wheel spindle 200 away from the first protrusion 210 has a mounting conical surface 560. The inner hole of the first pulley 510 is a tapered hole. The first pulley 510 is fixed to the grinding wheel spindle 200 through the mounting conical surface 560 in its inner hole, forming a tapered fit. A disassembly cavity 570 is formed in the inner hole of the first pulley 510. At least one oil passage hole 580 is formed on the end face of the first pulley 510, and the oil passage hole 580 communicates with the disassembly cavity 570. The first pulley 510 is fixed to the grinding wheel spindle 200 by the tapered fit of the mounting conical surface 560. The tapered fit ensures a very high coaxiality between the first pulley 510 and the grinding wheel spindle 200. A hydraulic device is connected to the oil passage 580 to introduce high-pressure hydraulic oil into the unloading cavity 570, so that the first pulley 510 can be easily disengaged from the mounting cone surface 560, which facilitates disassembly and solves the problem of difficult disassembly of interference fit or cone fit parts, making maintenance and replacement easier.

[0051] Reference Figure 5 In some embodiments, the housing 100 is provided with an air inlet 710 and a ventilation circuit 720. A sealing cover 750 is fixedly installed on the housing 100, and a ventilation groove 730 is provided on the sealing cover 750. The air inlet 710 and the ventilation circuit 720 are connected to the ventilation groove 730. A dustproof ring 740 is installed on the sealing cover 750. The processed compressed gas enters the ventilation groove 730 through the air inlet 710 and the ventilation circuit 720, making the air pressure there greater than the external atmospheric pressure. This effectively prevents oil leakage from inside the grinding wheel spindle 200 or external contaminants from being sucked into the housing 100. The ventilation groove 730 and the dustproof ring 740 together constitute an effective sealing and dustproof system, which can prevent extremely fine abrasive particles and dust generated during grinding from entering the precision bearing area, protecting the bearing system 400 and the grinding wheel spindle 200, and ensuring the long-term accuracy and life of the grinding wheel spindle 200.

[0052] Reference Figure 11 In some embodiments, a fully automatic balancing device 800 is fixedly mounted on the right end of the grinding wheel spindle 200. The fully automatic balancing device 800 can detect and compensate for imbalances in the grinding wheel spindle 200 and the grinding wheel 600 caused by uneven mass, installation errors, or wear in real time. It automatically and continuously corrects imbalances within the speed range, always suppressing vibration to a minimum. This ensures machining accuracy and surface quality at ultra-high speeds and significantly extends the service life of key components such as the bearing system 400 and the grinding wheel spindle 200.

[0053] Reference Figure 11In some embodiments, a belt guard 900 is also fixedly installed on the housing 100. The belt guard 900 effectively isolates the high-speed rotating transmission belt 540, eliminating the risk of operators coming into contact with transmission components, and complies with safety production regulations. It prevents external debris from being drawn into the transmission system, avoiding equipment downtime or damage accidents caused by it, and ensuring the continuity and stability of production.

[0054] The implementation principle of a novel ultra-high-speed grinding wheel box spindle structure of the present invention is as follows: The bearing system 400 integrates hydrostatic and hydrodynamic bearings 410, and through a fixed sleeve 450, a preload spring 460, and a bearing sleeve 470, provides stable axial positioning and preload for the high-speed grinding wheel spindle 200. This automatically compensates for the thermal expansion difference between the grinding wheel spindle 200 and the bearing system 400 caused by high-speed operation, enabling the grinding wheel spindle 200 to have axial self-adjustment capability. This effectively prevents the grinding wheel spindle 200 from axially seizing due to abnormal temperature rise, ensuring smooth operation of the bearing system 400. The grinding wheel positioning mechanism 300 uses an elastic positioning sleeve 310, combined with a clamping nut 330 and a fastening screw 320, to achieve automatic centering of the superhard grinding wheel 600 during installation and fixing, forming a high-rigidity and high-coaxiality clamping effect.

[0055] The above are all preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Therefore, all equivalent changes made in accordance with the structure, shape and principle of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A new type of ultra-high speed grinding wheel box spindle structure, characterized in that: The application relates to a grinding wheel positioning device, which comprises a box body (100), a grinding wheel spindle (200) and a bearing system (400), wherein the grinding wheel spindle (200) is rotatably arranged in the box body (100), and the grinding wheel spindle (200) is provided with a first protruding part (210) at one end close to the installation position of a grinding wheel (600); the bearing system (400) comprises a fixing sleeve (450), pre-tightening springs (460), locking screws (480) and a bearing sleeve (470), the fixing sleeve (450) is fixedly arranged on the grinding wheel spindle (200) through the locking screws (480), and the fixing sleeve (450) is located at one end of the grinding wheel spindle (200) away from the first protruding part (210); the bearing sleeve (470) is provided with a second protruding part (471), the bearing sleeve (470) is coaxially and slidably arranged on the grinding wheel spindle (200), and the pre-tightening springs (460) are fixedly arranged between the fixing sleeve (450) and the bearing sleeve (470); one end of the pre-tightening spring (460) is in abutment with the second protruding part (471), and the other end is in abutment with the fixing sleeve (450). The bearing system (400) further comprises a tight-pear bearing (440), the inner hole of the tight-pear bearing (440) is sleeved on the grinding wheel spindle (200), and the outer peripheral surface of the tight-pear bearing (440) is sleeved in the inner hole of the bearing sleeve (470). The outer periphery of the grinding wheel spindle (200) is sequentially provided with a positioning conical surface (220) and a positioning end surface (230) in the axial direction; The application further relates to a grinding wheel positioning mechanism (300), which comprises an elastic positioning sleeve (310), fastening screws (320) and a pressing nut (330), the inner hole of the elastic positioning sleeve (310) is conical; 2. The novel ultra-high speed grinding wheel cartridge spindle structure according to claim 1, characterized in that: A plurality of elastic openings (340) are formed in the circumferential direction of the elastic positioning sleeve (310), and the opening directions of two adjacent elastic openings (340) are opposite; 3. The novel ultra-high speed grinding wheel cartridge spindle structure according to claim 1, characterized in that: The pressing nut (330) is in threaded connection with the grinding wheel spindle (200), one end of the pressing nut (330) is in abutment with the elastic positioning sleeve (310), and the outer diameter of the elastic positioning sleeve (310) is in abutment with the inner diameter of the grinding wheel (600); A plurality of fastening screws (320) are fixedly connected with the positioning end surface (230) of the grinding wheel spindle (200), and the grinding wheel (600) is fixed on the grinding wheel spindle (200) through the fastening screws (320). The bearing system (400) further comprises two dynamic and static pressure bearings (410), the two dynamic and static pressure bearings (410) are oppositely arranged, the inner hole of one of the dynamic and static pressure bearings (410) is sleeved on the grinding wheel spindle (200), and the outer peripheral surface thereof is fixedly connected with the inner wall of the box body (100); the inner hole of the other dynamic and static pressure bearing (410) is sleeved on the bearing sleeve (470), and the outer peripheral surface thereof is fixedly connected with the inner wall of the box body (100); and the oil channel in the dynamic and static pressure bearing (410) is in communication with an oil supply system (430). ​ ​ 4. The novel ultra-high speed grinding wheel cartridge spindle structure according to claim 1, characterized in that: ​ 5. The novel ultra-high speed grinding wheel cartridge spindle structure according to claim 4, characterized in that: The inner hole of the dynamic static pressure bearing (410) is provided with a radial oil cavity (421), and the end face of one side of the dynamic static pressure bearing (410) is provided with an end face oil cavity (422); the end face oil cavity (422) of one of the dynamic static pressure bearings (410) acts on the first protruding part (210), and the end face oil cavity (422) of the other dynamic static pressure bearing (410) acts on the second protruding part (471).

6. The novel ultra-high speed grinding wheel cartridge spindle structure according to claim 5, characterized in that: A plurality of first oil inlet pipes (423) and a plurality of second oil inlet pipes (424) are further installed on the box body (100), the first oil inlet pipes (423) are in communication with the radial oil cavities (421), and the second oil inlet pipes (424) are in communication with the end face oil cavities (422); the inner hole of the dynamic static pressure bearing (410) is further provided with an oil return cavity (425), and the first oil inlet pipes (423), the second oil inlet pipes (424) and the oil return cavity (425) are all in communication with the oil supply system (430).

7. The novel ultra-high speed grinding wheel cartridge spindle structure according to claim 6, characterized in that: A constant temperature device (431) is further connected to the oil circuit between the dynamic static pressure bearing (410) and the oil supply system (430), and the constant temperature device (431) is used for temperature regulation and control of the hydraulic oil of the oil supply system (430).

8. The novel ultra-high speed grinding wheel cartridge spindle structure according to any one of claims 1-7, characterized in that: A driving mechanism (500) is further arranged on the box body (100), the driving mechanism (500) comprises a first pulley (510), a second pulley (520), a driving motor (530) and a transmission belt (540), the first pulley (510) is coaxially fixedly connected with the grinding wheel spindle (200), the driving motor (530) is fixedly installed on the box body (100), the second pulley (520) is fixedly installed on the output shaft of the driving motor (530), and the transmission belt (540) is sleeved on the first pulley (510) and the second pulley (520).

9. The novel ultra-high speed grinding wheel cartridge spindle structure according to claim 8, characterized in that: The end of the grinding wheel spindle (200) away from the first protruding part (210) is provided with a mounting conical surface (560), the inner hole of the first pulley (510) is a conical hole, the first pulley (510) is fixed with the grinding wheel spindle (200) through the mounting conical surface (560), the inner hole of the first pulley (510) is provided with a dismounting cavity (570), the end face of the first pulley (510) is provided with a plurality of oil holes (580), and the oil holes (580) are in communication with the dismounting cavity (570).

10. The novel ultra-high speed grinding wheel cartridge spindle structure according to claim 3, characterized in that: An air inlet (710) and an air circulation loop (720) are arranged on the box body (100), a sealing cover (750) is fixedly installed on the box body (100), an air vent groove (730) is arranged on the sealing cover (750), the air inlet (710) and the air circulation loop (720) are in communication with the air vent groove (730), and a dustproof ring (740) is installed on the sealing cover (750).

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