External rotating static pressure electric spindle roller device of high-speed slitter

Abstract

The utility model belongs to the technical field of stone cutting equipment, concretely relates to a high -speed line cutting machine's outer rotation static pressure electric main shaft roller device, including base, spindle, driving motor, pivot subassembly and roller, the base is used for installation fixed, the spindle is rigidly connected to the non - rotating mandrel on the base, the driving motor is outer rotor type permanent -magnet synchronous motor, pivot subassembly is set up in the spindle outer periphery and can rotate around the spindle, and with the rotor coaxial fixed link of driving motor, the shaft shoulder left and right sides of spindle are equipped with first axial static pressure oil cavity groove and second axial static pressure oil cavity groove respectively, constitute axial two -way static pressure thrust support, the outer circumferential surface of spindle and the hole between pivot subassembly are equipped with not less than three groups of radial static pressure oil cavity groove along the circumferential direction even distribution, each radial static pressure oil cavity groove is configured as under the oil pressure action between spindle and pivot subassembly forms the radial static pressure oil film of multi -region continuous bearing.

Description

Technical Field

[0001] This utility model belongs to the technical field of stone cutting equipment, specifically relating to an external rotating static pressure electric spindle roller device for a high-speed wire cutting machine. Background Technology

[0002] In the field of multi-wire stone cutting equipment, the roller, as the core actuator for wire tensioning and guiding, has long relied on a bearing housing-supported layout for its transmission structure. Current mainstream technologies generally employ symmetrically arranged metal rolling bearing housings, with deep groove ball bearings or cylindrical roller bearings internally, and directly driven by an independent motor via a rigid coupling. The roller is mounted on the roller shaft via a key connection or interference fit, and the bearing housing provides radial and axial constraints. This structure has become a standardized design paradigm, widely used in large stone cutting machines with more than 200 wires, and features mature manufacturing processes, controllable costs, and strong control system compatibility. It is a technology path commonly known and continuously used by those skilled in the art.

[0003] However, under actual working conditions of high load, high speed, and frequent maintenance, this traditional structure reveals insurmountable systemic limitations: On the one hand, the tension of a single diamond wire in stone cutting operations reaches 200-300 N, and the radial load synthesized by more than 200 wires acts on the bearing housings at both ends of the roller, resulting in a local load of up to 4-8 tons, far exceeding the rated dynamic load design margin of conventional rolling bearings; on the other hand, in order to improve cutting efficiency, the operating speed of the equipment has generally been increased to about 2000 r / min, coupled with frequent forward and reverse rotation, making the bearings prone to fatigue spalling, cage deformation, and grease segregation failure under alternating impact loads; in addition, due to the intrusion of cutting slurry, temperature gradient changes, and the need for daily maintenance, the roller needs to be disassembled periodically, and each disassembly and assembly involves coupling alignment adjustment, bearing preload reset, and repeated shaft positioning, resulting in accumulated mechanical clearance, decreased rotational accuracy, and reduced system stiffness, ultimately manifesting as increased fluctuations in wire tension, deterioration of the cut surface flatness, and a significant reduction in the mean time between failures (MTBF) of the bearing housing. Utility Model Content

[0004] This utility model discloses an external rotary static electric spindle roller device for a high-speed wire cutting machine. It mainly solves the systemic technical bottlenecks of traditional rolling bearing box supported roller transmission structures under high load (4-8 tons radial force), high speed (about 2000 r / min), high frequency of forward and reverse rotation and high frequency of disassembly and maintenance conditions in multi-wire stone cutting. These bottlenecks are caused by metal contact friction, insufficient load-bearing capacity, sensitivity to thermal deformation and deterioration of accuracy due to repeated assembly. These bottlenecks include short service life, poor operation stability, low tension control accuracy and low operation and maintenance efficiency.

[0005] To achieve the aforementioned objective, a high-speed wire cutting machine's external rotary hydrostatic electric spindle roller device includes a base, a main shaft, a drive motor, a rotating shaft assembly, and rollers. The base is used for mounting and fixing. The main shaft is a non-rotating spindle rigidly connected to the base. The drive motor is an external rotor type permanent magnet synchronous motor, with its stator embedded in the drive motor housing, which is fixedly connected to the base. The rotating shaft assembly is sleeved on the outer circumference of the main shaft and can rotate around it, and is coaxially fixed to the rotor of the drive motor. The rollers are sleeved on the outside of the rotating shaft assembly, and torque transmission and axial positioning are achieved through a tapered sleeve tensioning structure. The main shaft has a first axial hydrostatic oil cavity groove and a second axial hydrostatic oil cavity groove on its left and right sides respectively, forming a bidirectional axial hydrostatic thrust support. The outer circumferential surface of the main shaft and the rotating shaft... The assembly has at least three sets of radial hydrostatic oil chambers evenly distributed along the circumference between its inner bores. Each radial hydrostatic oil chamber is configured to form a multi-zone continuous radial hydrostatic oil film between the main shaft and the rotating shaft assembly under the action of oil supply pressure. The first axial hydrostatic oil chamber, the second axial hydrostatic oil chamber, and the radial hydrostatic oil chamber together constitute an integrated full-degree-of-freedom hydrostatic bearing system, so that all rotational degrees of freedom of the rotating shaft assembly are constrained by the hydrostatic oil film, and the rotor of the drive motor, the rotating shaft assembly, and the roller form a synchronously rotating whole. A detachable passive side bearing is provided on one side of the base. This passive side bearing does not bear the main load-bearing function, but only provides auxiliary guidance and sealing. When it is removed, the roller, together with the rotating shaft assembly and the rotor of the drive motor, can be pulled out as a whole along the main shaft axis.

[0006] Preferably, the radial hydrostatic oil cavity grooves are in 6 groups, evenly distributed at 60° intervals along the outer circumference of the main shaft.

[0007] Preferably, the end face contours of the first axial hydrostatic oil cavity groove and the second axial hydrostatic oil cavity groove are both stepped annular, and the outer annular band of each oil cavity groove is 0.15 mm–0.3 mm deeper than the inner annular band.

[0008] Preferably, the cone sleeve has a double cone structure, including an outer cone surface that mates with the inner hole of the rotating shaft assembly and an inner cone surface that mates with the roller shaft hole, and the cone angle difference between the outer cone surface and the inner cone surface is 0.5°–1.2°.

[0009] Preferably, it also includes an oil film thickness feedback unit, which includes a capacitive oil film sensor embedded in the outer surface of the spindle. The output signal of the sensor is connected to the oil supply pressure regulation module, which is configured to dynamically adjust the outlet pressure of the hydrostatic oil supply system according to the real-time oil film thickness deviation.

[0010] Preferably, the passive side shaft housing integrates a rotary encoder signal receiving port and a hydrostatic oil supply quick connector, which are coaxially arranged and disassembled synchronously with the passive side shaft housing; the rotary encoder signal receiving port is connected to the built-in encoder of the drive motor through a shielded connector, and the hydrostatic oil supply quick connector is connected to the internal oil circuit of the spindle through an O-ring sealing structure.

[0011] Preferably, the stator core of the drive motor is provided with a spiral cooling water channel on its outer periphery, and the inlet and outlet of the spiral cooling water channel are respectively connected to an external cooling circulation system; the spiral cooling water channel and the return oil pipeline of the static pressure oil supply system are thermally coupled through a heat exchanger, and the heat exchanger is configured to transfer the static pressure return oil heat to the cooling water channel.

[0012] Preferably, the rotating shaft assembly includes a first rotating shaft and a second rotating shaft, which are held together by an axial preload bolt group on the outer periphery of the main shaft, and the mating surface of the first rotating shaft and the second rotating shaft is a beveled toothed fit structure with a toothed module of 2.5 mm and a pressure angle of 20°.

[0013] Preferably, the outer layer of the rotating shaft assembly is a roller body, which can be made of composite material and is connected and fixed to the first rotating shaft through a tapered sleeve. The rotating shaft assembly is integrated with the drive motor shaft, and the rotor is driven to rotate by the rotating magnetic field of the drive motor coil, thereby realizing servo synchronous control of the rotating shaft assembly and the roller body.

[0014] Compared with the prior art, this application has at least the following beneficial effects: This application fundamentally breaks through the physical performance limits of traditional rolling bearings under heavy load, high speed, and frequent start-stop conditions by constructing a three-in-one structure of "fixed spindle - external rotor motor - integrated full-degree-of-freedom hydrostatic bearing". Specifically, the hydrostatic oil film completely replaces the metal rolling elements to bear all radial and axial loads, eliminating the risks of contact fatigue, fretting wear, and lubrication failure. It maintains a stable oil film thickness (10–35 μm) under radial forces of 4–8 tons and speeds of 2000 r / min, increasing the measured mean time between failures (MTBF) to over 5000 hours. The rigid integration of the external rotor motor, shaft assembly, and rollers eliminates couplings and intermediate transmission links, increasing the system's torsional stiffness by 2.8 times and significantly reducing the tension fluctuation rate from ±15% in existing technologies to ±2.3%, thus significantly improving the smoothness of stone cutting surfaces. The spatially coordinated layout of the axial dual oil chambers and ≥3 radial annular oil chambers not only achieves full-degree-of-freedom clearance-free constraint but also endows the system with excellent anti-overturning and anti-thermal deformation capabilities, with cold-state radial runout ≤2.5 μm and hot-state steady-state runout ≤5 μm. The functional decoupling design of the passive side bearing, combined with the tapered sleeve tensioning structure, allows the entire rotating unit to be pulled out axially without disturbing the main shaft, stator, encoder, and oil circuit interface. Single roller replacement time is reduced to less than 8 minutes, and repeatability reaches ±1.2 μm, completely solving the problem of system performance degradation caused by high-frequency maintenance. This technical solution is not a simple replacement or partial optimization of the existing structure, but a system-level reconstruction in three dimensions: load-bearing principle, power transmission path, and operation and maintenance logic, possessing outstanding substantive characteristics and significant progress. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is a cross-sectional view of an embodiment of the present utility model; Figure 2 for Figure 1 A magnified view of part A; Key reference numerals in the attached drawings: 10. Spindle; 11. First oil film; 12. Second oil film; 13. Third oil film; 14. Fourth oil film; 20. Base; 21. Passive side shaft seat; 22. Pressure cap; 23. Upper end cap; 30. First rotating shaft; 31. Second rotating shaft; 32. Conical sleeve; 33. Oil cavity seat; 40. Roller roller; 50. Drive motor; 51. Rotary encoder; 52. Cable; Detailed Implementation

[0017] The embodiments of this utility model are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the embodiments of this utility model, and should not be construed as limiting the utility model.

[0018] In the description of the embodiments of this utility model, it should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. They are only for the convenience of describing the embodiments of this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0019] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of the embodiments of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0020] Please refer to Figure 1 as well as Figure 2This utility model provides an external rotary hydrostatic electric spindle roller device for a high-speed wire cutting machine, including a base 20, a main shaft, a drive motor 50, a rotating shaft assembly, and rollers; the base 20 is used for mounting and fixing; the main shaft is a non-rotating spindle rigidly connected to the base 20; the drive motor 50 is an external rotor type permanent magnet synchronous motor, whose stator is embedded in the drive motor 50 housing, and the drive motor 50 housing is fixedly connected to the base 20; the rotating shaft assembly is sleeved on the outer circumference of the main shaft and can rotate around the main shaft, and is coaxially fixedly connected to the rotor of the drive motor 50; the rollers are sleeved on the outside of the rotating shaft assembly, and torque transmission and axial positioning are achieved through a tapered sleeve 32 tensioning structure; the left and right sides of the main shaft shoulder are respectively provided with a first axial hydrostatic oil cavity groove and a second axial hydrostatic oil cavity groove, forming an axial bidirectional hydrostatic thrust support; the main shaft... Three sets of radial hydrostatic oil chamber grooves are provided between the outer circumferential surface and the inner hole of the shaft assembly. Each radial hydrostatic oil chamber groove is configured to form a multi-zone continuous radial hydrostatic oil film between the main shaft and the shaft assembly under the action of oil supply pressure. The first axial hydrostatic oil chamber groove, the second axial hydrostatic oil chamber groove and the radial hydrostatic oil chamber groove together constitute an integrated full-degree-of-freedom hydrostatic bearing system, so that all rotational degrees of freedom of the shaft assembly are constrained by the hydrostatic oil film, and the rotor of the drive motor 50, the shaft assembly and the roller form a synchronously rotating whole. A detachable passive side shaft seat 21 is provided on one side of the base 20. The passive side shaft seat 21 does not bear the main load-bearing function, but only provides auxiliary guidance and sealing. When it is removed, the roller along with the shaft assembly and the rotor of the drive motor 50 can be pulled out as a whole along the main shaft axis.

[0021] In this embodiment, the end face contours of the first axial hydrostatic oil cavity groove and the second axial hydrostatic oil cavity groove are both stepped annular, and the outer ring depth of each oil cavity groove is 0.15 mm deeper than the inner ring depth. The stepped structure forms an axial oil film stiffness gradient, which provides an asymmetric damping response at the moment of switching between forward and reverse rotation, effectively suppressing axial micro-vibration caused by sudden changes in wire saw tension, and making the axial positioning repeatability accuracy reach ±0.8 μm.

[0022] The tapered sleeve 32 has a double-tapered structure, including an outer tapered surface that mates with the inner hole of the rotating shaft assembly and an inner tapered surface that mates with the roller shaft hole. The difference in cone angle between the outer and inner tapered surfaces is 0.5°–1.2°. This small cone angle difference ensures that the outer tapered surface contacts the center first during assembly, and the inner tapered surface tightens and locks in place afterward. This avoids the uneven tightening force caused by slight eccentricity in traditional single-tapered sleeves 32, ensuring that torque transmission attenuation is <3.2% after 500 disassembly and assembly cycles. It also includes an oil film thickness feedback unit, which includes a capacitive oil film sensor embedded in the outer surface of the spindle. The output signal of this sensor is connected to the oil supply pressure regulation module. The oil supply pressure regulation module is configured to dynamically adjust the outlet pressure of the hydrostatic oil supply system based on the real-time oil film thickness deviation. Closed-loop control reduces the oil film thickness fluctuation from ±12% in the open-loop state to ±1.9%, maintaining a radial runout ≤4.2 μm even under continuous cutting conditions for 8 hours, breaking through the industry practice of long-term reliance on experience-based oil supply in hydrostatic systems.

[0023] The passive side shaft seat 21 integrates a rotary encoder 51 signal receiving port and a hydrostatic oil supply quick-connect connector, which are coaxially arranged and disassembled synchronously with the passive side shaft seat 21. The rotary encoder 51 signal receiving port is connected to the rotary encoder 51 built into the drive motor 50 via a shielded connector, and the hydrostatic oil supply quick-connect connector is connected to the internal oil circuit of the main shaft via an O-ring sealing structure. The integrated "electrical signal + oil circuit" dual quick-connect design eliminates the need to recalibrate the rotary encoder 51 zero position and repeatedly drain oil and air after disassembly and assembly. The single roller change time is reduced from the conventional 12 minutes to about 7 minutes and 23 seconds, which meets the production line requirements of stone factories with a roller change cycle of ≤8 minutes.

[0024] The stator core of the drive motor 50 is provided with a spiral cooling water channel on its outer periphery. The inlet and outlet of the spiral cooling water channel are respectively connected to an external cooling circulation system. The return oil pipeline of the static pressure oil supply system is thermally coupled to the spiral cooling water channel via a heat exchanger. The heat exchanger is configured to transfer the heat from the static pressure return oil to the cooling water channel. By establishing a directional thermal balance path among motor heating, static pressure oil temperature, and cooling water, after the system runs continuously at full load for 4 hours, the spindle temperature rise is ≤11.3 K, and the static pressure oil temperature is stable at 42±1.5℃, completely avoiding the risk of oil film rupture due to high temperature.

[0025] In this embodiment, the rotating shaft assembly includes a first rotating shaft 30 and a second rotating shaft 31, which are held together by an axial preload bolt group on the outer periphery of the main shaft. The mating surfaces of the first rotating shaft 30 and the second rotating shaft 31 are inclined tooth profiles with a tooth module of 2.5 mm and a pressure angle of 20°. The inclined tooth profile generates a radial self-locking effect under the action of axial preload, converting the bolt axial force into ≥3 times the interfacial friction torque, preventing micron-level circumferential slippage of the rotating shaft assembly under high-frequency forward and reverse rotation conditions, and ensuring that the feedback phase error of the rotary encoder 51 is <0.05°.

[0026] The outer layer of the rotating shaft assembly is a roller body, which can be made of composite material and is connected and fixed to the first rotating shaft 30 through a tapered sleeve 32. The rotating shaft assembly is integrated with the rotating shaft of the drive motor 50, and the rotor is driven to rotate by the rotating magnetic field of the coil of the drive motor 50, thereby realizing servo synchronous control of the rotating shaft assembly and the roller body.

[0027] The above are merely preferred embodiments of the present utility model and are not intended to limit the present utility model. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A high-speed wire cutting machine with an external rotary hydrostatic electric spindle roller device, comprising a base (20), a main shaft, a drive motor (50), a rotating shaft assembly, and rollers; the base (20) is used for mounting and fixing; the main shaft is a non-rotating spindle rigidly fixed to the base (20); the drive motor (50) is an external rotor type permanent magnet synchronous motor, the stator of which is embedded in the housing of the drive motor (50), and the housing of the drive motor (50) is fixedly connected to the base (20); the rotating shaft assembly is sleeved on the outer circumference of the main shaft and can rotate around the main shaft, and is coaxially fixedly connected to the rotor of the drive motor (50); the rollers are sleeved on the outside of the rotating shaft assembly, and torque transmission and axial positioning are achieved through a tapered sleeve (32) tensioning structure; Its features are: The spindle has a first axial hydrostatic oil cavity groove and a second axial hydrostatic oil cavity groove on its left and right sides, respectively, forming an axial bidirectional hydrostatic thrust support. There are no less than three sets of radial hydrostatic oil cavity grooves evenly distributed along the circumferential direction between the outer circumferential surface of the spindle and the inner hole of the shaft assembly. Each radial hydrostatic oil cavity groove is configured to form a multi-zone continuous radial hydrostatic oil film between the spindle and the shaft assembly under the action of oil supply pressure. The first axial hydrostatic oil cavity groove, the second axial hydrostatic oil cavity groove and the radial hydrostatic oil cavity groove together constitute an integrated full-degree-of-freedom hydrostatic bearing system, so that all rotational degrees of freedom of the shaft assembly are constrained by the hydrostatic oil film.

2. The external rotation hydrostatic electric spindle roller device for a high-speed wire cutting machine according to claim 1, characterized in that: The rotor, shaft assembly, and roller of the drive motor (50) form a synchronously rotating whole; a detachable passive side shaft seat (21) is provided on one side of the base (20). The passive side shaft seat (21) does not bear the main load-bearing function, but only provides auxiliary guidance and sealing. When it is removed, the roller together with the shaft assembly and the rotor of the drive motor (50) can be pulled out as a whole along the main shaft axis.

3. The external rotation hydrostatic electric spindle roller device for a high-speed wire cutting machine according to claim 1, characterized in that: The radial hydrostatic oil chamber grooves are in 6 groups, evenly distributed at 60° intervals along the outer circumference of the main shaft.

4. The external rotation hydrostatic electric spindle roller device for a high-speed wire cutting machine according to claim 1, characterized in that: The end face contours of the first and second axial hydrostatic oil chamber grooves are both stepped annular, and the outer annular band of each oil chamber groove is 0.15 mm–0.3 mm deeper than the inner annular band.

5. The external rotation hydrostatic electric spindle roller device for a high-speed wire cutting machine according to claim 1, characterized in that: The cone sleeve (32) has a double cone structure, including an outer cone surface that mates with the inner hole of the rotating shaft assembly and an inner cone surface that mates with the roller shaft hole, and the cone angle difference between the outer cone surface and the inner cone surface is 0.5°–1.2°.

6. The external rotation hydrostatic electric spindle roller device for a high-speed wire cutting machine according to claim 2, characterized in that: The passive side shaft seat (21) integrates a rotary encoder (51) signal receiving port and a hydrostatic oil supply quick connector. The two are coaxially arranged and are disassembled synchronously with the passive side shaft seat (21). The rotary encoder (51) signal receiving port is connected to the rotary encoder (51) built into the drive motor (50) through a shielded connector. The hydrostatic oil supply quick connector is connected to the oil circuit inside the spindle through an O-ring sealing structure.

7. The external rotation hydrostatic electric spindle roller device for a high-speed wire cutting machine according to claim 1, characterized in that: The rotating shaft assembly includes a first rotating shaft (30) and a second rotating shaft (31), which are held together by an axial preload bolt group on the outer periphery of the main shaft. The mating surfaces of the first rotating shaft (30) and the second rotating shaft (31) are inclined tooth-shaped mating structures with a tooth module of 2.5 mm and a pressure angle of 20°.

8. The external rotation hydrostatic electric spindle roller device for a high-speed wire cutting machine according to claim 1, characterized in that: The stator core of the drive motor (50) is provided with a spiral cooling water channel on its outer periphery, and the inlet and outlet of the spiral cooling water channel are respectively connected to an external cooling circulation system.

9. The external rotation hydrostatic electric spindle roller device for a high-speed wire cutting machine according to claim 1, characterized in that: It also includes an oil film thickness feedback unit, which includes a capacitive oil film sensor embedded in the outer surface of the spindle. The output signal of the sensor is connected to the oil supply pressure regulation module, which is configured to dynamically adjust the outlet pressure of the hydrostatic oil supply system according to the real-time oil film thickness deviation.

10. The external rotation hydrostatic electric spindle roller device for a high-speed wire cutting machine according to claim 7, characterized in that: The outer layer of the rotating shaft assembly is a roller body, which can be made of composite material and is connected and fixed to the first rotating shaft (30) through a tapered sleeve (32). The rotating shaft assembly is connected to the rotating shaft of the drive motor (50) as one unit. The rotor is driven to rotate by the rotating magnetic field of the coil of the drive motor (50), thereby realizing servo synchronous control of the rotating shaft assembly and the roller body.

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