WO2021248891A1

WO2021248891A1 - Motorized spindle core component, air bearing motorized spindle and drilling machine

Info

Publication number: WO2021248891A1
Application number: PCT/CN2020/141688
Authority: WO
Inventors: 朱胜利; 汤丽君; 汤秀清
Original assignee: 广州市昊志机电股份有限公司
Priority date: 2020-06-08
Filing date: 2020-12-30
Publication date: 2021-12-16
Also published as: CN111842943B; CN111842943A

Abstract

A motorized spindle core component, comprising: a spindle core (5), having a spindle core inner hole (51); a tool clamping mechanism, comprising a clamp head inner core (71) and a clamp head sleeve (72), the clamp head sleeve (72) being connected to an end part of the spindle core (5); a spindle master mechanism (8), comprising a sliding sleeve (82) and a sliding sleeve core (83), the sliding sleeve (82) being arranged in the spindle core inner hole (51), the sliding sleeve (82) being fitted over the external side of the sliding sleeve core (83), the sliding sleeve (82) having a conical inner hole, the sliding sleeve core (83) having an external conical surface matching the conical inner hole, and the sliding sleeve core (83) being connected to the clamp head inner core (71); and an elastic part (81), which is arranged between the sliding sleeve (82) and the clamp head sleeve (72) and abuts against the sliding sleeve (82). Also disclosed are an air bearing motorized spindle and a drilling machine comprising the motorized spindle core component. In the air bearing motorized spindle and the drilling machine, by adopting a spindle master structure capable of compensating fitting variable quantity caused by temperature and centrifugal expansion changes, the problem that the vibrating performance of a spindle is not stable due to mass eccentricity of a tool clamping mechanism in a spindle core high speed rotating process is effectively solved, and the low vibrating performance of the spindle is realized.

Description

Electric spindle shaft core assembly, air-floating electric spindle and drilling rig

This application claims the priority of a Chinese patent application filed with the Chinese Patent Office with an application number of 202010513698.2 on June 8, 2020. The entire content of this application is incorporated into this application by reference.

Technical field

The present application is used in the field of rotary machining, for example, it relates to an electric spindle shaft assembly, an air-floating electric spindle, and a drilling machine.

Background technique

The vigorous development of the optoelectronic industry, integrated circuits, and consumer electronics products requires higher and higher requirements for drilling processing technology in the PCB industry. There are two main factors restricting the development of processing technology. One is the development of drilling processing technology; the other is the implementation of drilling. Accuracy of the air-floating electric spindle, the core component of hole processing; research shows that the performance index of the core component of the air-floating electric spindle is the key factor affecting the quality of drilling processing, such as the torque of the spindle motor, the vibration speed and amplitude, and the dynamic extension of the shaft core The amount of change, etc.

In the related art, during the high-speed rotation of the shaft core, temperature changes, centrifugal expansion changes and other factors affect the sleeve of the tool clamping mechanism and the inner hole of the shaft core to produce a small gap, resulting in mass eccentricity, changing the initial balance of the shaft system, and causing the spindle vibration to change Large or unstable.

Summary of the invention

The present application solves at least one of the technical problems existing in the related technology. It provides an electric spindle shaft core assembly, an air-floating electric spindle and a drilling rig. It innovatively adopts a new type of shaft hegemony structure that can compensate for changes in temperature and centrifugal expansion, which is effective Solve the problem of unstable spindle vibration performance caused by mass eccentricity of the tool clamping mechanism during the high-speed rotation of the shaft core, and realize the characteristics of low vibration performance of the spindle.

The technical solutions adopted by this application to solve its technical problems are:

In the first aspect, an electric spindle shaft core assembly includes:

Shaft core with inner hole of shaft core;

The clamping mechanism includes a chuck inner core and a chuck sleeve, the chuck sleeve is connected to the end of the shaft core;

The hub mechanism includes a sliding sleeve and a sliding sleeve core, the sliding sleeve is arranged in the inner hole of the shaft core, the sliding sleeve is sleeved outside the sliding sleeve core, and the sliding sleeve has a tapered inner hole, so The sliding sleeve core has an outer conical surface matched with the tapered inner hole, and the sliding sleeve core is connected with the inner core of the chuck;

An elastic component is arranged between the sliding sleeve and the chuck sleeve, and the elastic component abuts against the sliding sleeve.

With reference to the first aspect, in some implementations of the first aspect, a plurality of deformation grooves are provided on the sliding sleeve.

Combining the first aspect and the foregoing implementation manners, in some implementation manners of the first aspect, the outer peripheral surface of the tail of the sliding sleeve is provided with a limit stop ring, and the hub mechanism further includes:

An elastic outer sleeve is sleeved on the outside of the sliding sleeve, and the elastic outer sleeve abuts against the limit stop ring.

Combining the first aspect and the foregoing implementation manners, in some implementation manners of the first aspect, the tail end surface of the sliding sleeve protrudes from the tail end surface of the sliding sleeve core.

Combining the first aspect and the foregoing implementation manners, in some implementation manners of the first aspect, an adjustment component is provided at the tail of the sliding sleeve core, the adjustment component is threadedly connected with the sliding sleeve core, and the adjustment component sinks Inside the sliding sleeve, the tail end surface of the sliding sleeve protrudes from the tail end surface of the adjusting component.

In the second aspect, an air-floating electric spindle includes:

The body is provided with shaft holes and air flow channels;

In the electric spindle shaft core assembly according to any one of the implementation manners of the first aspect, the shaft core is inserted into the shaft hole, and a thrust flying disc is provided on the chuck sleeve;

The driving part, the output end is provided with a push rod, the push rod extends into the inner hole of the shaft core, and is used to push the shaft hegemony mechanism;

The motor assembly includes a stator and a rotor, and the rotor is connected to the shaft core;

An air bearing is arranged in the shaft hole and is matched with the shaft core;

Thrust bearing, which cooperates with the thrust flying disc;

Wherein, the air bearing and the thrust bearing both have exhaust holes connected to the air flow channel.

With reference to the second aspect, in some implementations of the second aspect, the stator has multiple windings, and the multiple windings correspond to different rated speeds of the motor components.

Combining the second aspect and the foregoing implementation manners, in some implementation manners of the second aspect, the stator is located in the shaft hole, the stator is connected to the body, and the body is provided on the outside of the shaft hole. Cooling water jacket.

Combining the second aspect and the foregoing implementation manners, in some implementation manners of the second aspect, the air bearing includes a first air bearing and a second air bearing, and the first air bearing and the second air bearing The bearings are distributed on both sides of the motor assembly.

In a third aspect, a drilling rig includes the air-floating electric spindle described in any implementation manner of the second aspect.

One of the above technical solutions has at least one of the following advantages or beneficial effects: this technical solution designs a real-time variable-size shaft-holding mechanism, that is, under the action of an elastic component, it is transmitted to the sliding sleeve through a tapered surface to cause the outer circle size to increase. , Eliminate the tiny gap generated, and ensure that the coordination between the axle tyrant mechanism and the inner hole of the axle core is always the same. This technical solution innovatively adopts a new type of shaft hegemony structure that can compensate for the change in coordination caused by temperature and centrifugal expansion changes, which effectively solves the problem of unstable spindle vibration performance caused by the mass eccentricity of the tool clamping mechanism during the high-speed rotation of the shaft core, and realizes the characteristics of low-vibration performance of the spindle.

The additional aspects and advantages of the present application will be partially given in the following description, and some will become obvious from the following description, or be understood through the practice of the present application.

Description of the drawings

The above and/or additional aspects and advantages of the present application will become obvious and easy to understand from the description of the embodiments in conjunction with the following drawings, in which:

Fig. 1 is a schematic structural diagram of an embodiment of the air-floating electric spindle of the present application;

2 is a schematic structural diagram of an embodiment of the shaft core assembly of the electric spindle of the present application;

Figure 3 is a schematic view of the rear end of the hub mechanism of the embodiment shown in Figure 2;

Figure 4 is a cross-sectional view at A-A in Figure 3;

Fig. 5 is an axonometric schematic diagram of the hub mechanism of the embodiment shown in Fig. 2;

Fig. 6 is a schematic diagram of the stator structure of the embodiment shown in Fig. 2.

detailed description

In this application, if there is a description of directions (up, down, left, right, front and back), it is only for the convenience of describing the technical solutions of this application, rather than indicating or implying that the technical features referred to must have specific Orientation, construction and operation in a specific orientation, therefore cannot be understood as a limitation of the application.

In this application, "several" means one or more, "multiple" means two or more, "greater than", "less than", "exceeding", etc. are understood to not include the number; "above", "below", and "within" "And so on are understood to include the number. In the description of this application, if there is a description of "first" and "second" only for the purpose of distinguishing technical features, it cannot be understood as indicating or implying the relative importance or implicitly indicating the number or quantity of the indicated technical features. Implicitly indicate the sequence of the indicated technical features.

In this application, unless specifically defined otherwise, terms such as "setting", "installation", and "connection" should be understood in a broad sense. For example, it can be directly connected or indirectly connected through an intermediary; it can be a fixed connection or The detachable connection can also be integrally formed; it can be a mechanical connection, or it can be an electrical connection or can communicate with each other; it can be a communication between two components or an interaction relationship between two components. Those skilled in the art can reasonably determine the specific meaning of the above words in this application in combination with the specific content of the technical solution.

Referring to Figure 1, the embodiment of the present application provides an air-floating electric spindle, which includes a body 1, an electric spindle shaft core assembly, a driving part 2, a motor assembly 3, an air bearing and a thrust bearing 4, and the body 1 is an assembly spindle The carrier, the body 1 is provided with a shaft hole 11. The shaft core assembly of the electric spindle includes a shaft core 5, which is inserted into the shaft hole 11 of the body 1, and an air bearing is arranged in the shaft hole 11 and is matched with the shaft core 5. The motor assembly 3 includes a stator 31 and a rotor 32, the rotor 32 is connected to the shaft core 5, and the motor assembly 3 is used to drive the shaft core 5 to rotate with high precision in the shaft hole 11 of the body 1.

The shaft core assembly of the electric spindle also includes a tool clamping mechanism, which is used to clamp the tool 6, as shown in Figures 1 and 2. The tool clamping mechanism includes a chuck inner core 71 and a chuck sleeve 72. The chuck inner core 71 has a clamping In the clamping inner hole of the tool 6, the chuck inner core 71 and the chuck sleeve 72 are matched by a conical surface. When the chuck inner core 71 is retracted into the chuck sleeve 72, the clamping of the chuck inner core 71 is Hold the inner hole to shrink and clamp the inner tool 6.

1, the chuck sleeve 72 is connected to the end of the shaft core 5, the chuck sleeve 72 is provided with a thrust flying disc 73, the thrust bearing 4 is matched with the thrust flying disc 73, and the body 1 is provided with an air flow channel and an air bearing Both the thrust bearing 4 and the thrust bearing 4 have exhaust holes connected to the air flow channel. When in use, through external air supply, the gas enters the air bearing and thrust bearing 4 through the air flow channel, and is ejected from the exhaust hole, so that it is between the shaft core 5 and the air bearing, the thrust bearing 4 and the thrust flying disc A pressure air film is formed between 73 and the supporting shaft core 5 is in a suspended state. Driven by the motor assembly 3, the shaft core 5 performs high-precision and high-speed rotation, and further outputs the power of the motor assembly 3 to the tool 6 of the clamping mechanism.

2, the shaft core 5 has a shaft core inner hole 51, the electric spindle shaft core assembly further includes a shaft brake mechanism 8 and an elastic member 81, the shaft brake mechanism 8 includes a sliding sleeve 82 and a sliding sleeve core 83, the sliding sleeve 82 is arranged on the shaft In the core inner hole 51, the sliding sleeve 82 is sleeved on the outside of the sliding sleeve core 83, the other end of the sliding sleeve core 83 penetrates into the inside of the chuck sleeve 72, the sliding sleeve core 83 is connected with the chuck inner core 71, and the hub mechanism 8 is located along the shaft core. When the hole 51 reciprocates, the chuck core 71 is driven to extend or retract, thereby releasing or clamping the tool 6.

Referring to Fig. 1, the output end of the driving part 2 is provided with a push rod 21, which extends into the inner hole 51 of the shaft core for pushing the shaft hegemony mechanism 8. The elastic part 81 is arranged between the sliding sleeve 82 and the chuck sleeve 72, The elastic component 81 can be a spring, a disc spring group, etc., and the elastic component 81 abuts the sliding sleeve 82. The driving part 2 can be an air cylinder, a motor, etc. For example, in the embodiment shown in FIG. The ejector rod 21 pushes the spindle mechanism 8, the spindle mechanism 8 pushes the inner core 71 of the chuck, and the tool clamping mechanism releases the tool 6. After occluding the air, the elastic member 81 pushes the shaft brake mechanism 8 to reset, and the shaft brake mechanism 8 pulls the chuck inner core 71 to retract and clamp the tool 6.

Referring to Figures 3 and 4, in the hub mechanism 8, the sliding sleeve 82 has a tapered inner hole, and the sliding sleeve core 83 has an outer tapered surface that matches the tapered inner hole. The outer tapered surface and the tapered inner hole have the same taper or The difference is that the sliding sleeve core 83 and the sliding sleeve 82 are matched by a tapered surface. When the sliding sleeve core 83 and the sliding sleeve 82 move relative to each other in the axial direction, the outer size of the sliding sleeve 82 can be enlarged or reduced. During the working process, the elastic member 81 provides elastic support for the hub mechanism 8 to form a real-time variable-size hub mechanism 8. That is, under the action of the elastic member 81, it is transmitted to the sliding sleeve 82 through the tapered surface to cause the outer circle size to increase, eliminating The small gap generated between the sliding sleeve 82 and the shaft core 5 ensures that the coordination between the shaft tyrant mechanism 8 and the shaft core inner hole 51 is always constant. This technical solution innovatively adopts a new type of shaft hegemony structure that can compensate for changes in temperature and centrifugal expansion, which effectively solves the problem of unstable spindle vibration performance caused by mass eccentricity of the tool clamping mechanism during high-speed rotation of shaft 5, and achieves low-vibration performance characteristics of the spindle .

In some embodiments, referring to Figures 3 and 5, the sliding sleeve 82 is cylindrical. The sliding sleeve 82 is provided with a number of deformation grooves 84. The deformation grooves 84 extend to the tail edge of the sliding sleeve 82. The sliding sleeve 82 is uniformly or non-uniformly distributed in the axial direction, and the arrangement of the deformation groove 84 can provide the sliding sleeve 82 with a larger deformation space.

The sliding sleeve 82 can be in direct or indirect contact with the shaft core 5. For example, in some embodiments, referring to Figures 3, 4, and 5, the hub mechanism 8 also includes an elastic outer sleeve 85, which is formed by covering the outer side of the sliding sleeve 82 The jacket assembly, the elastic jacket 85 is made of engineering elastic material. The elastic jacket 85 is located between the sliding sleeve 82 and the shaft core 5. On the one hand, the shaft master mechanism 8 and the shaft core 5 are more closely matched to eliminate the small gap generated. On the one hand, the material wear caused by the rigid contact between the sliding sleeve 82 and the shaft core 5 can also be avoided.

Further, referring to Figures 4 and 5, the outer peripheral surface of the tail of the sliding sleeve 82 is provided with a limit stop ring 86. The outer peripheral surface of the sliding sleeve 82 forms a space connecting the elastic jacket 85 through the limit stop ring 86, and the elastic jacket 85 abuts against the limit stop ring 86. The stop ring 86 prevents the elastic jacket 85 from detaching from the sliding sleeve 82 during the reciprocating movement of the sliding sleeve 82.

Because the hub mechanism 8 is automatically swelled in the inner hole 51 of the shaft core under the action of the elastic member 81, when the push rod 21 of the driving part 2 pushes the hub mechanism 8, the hub mechanism 8 needs to be unlocked to avoid damage to the shaft. Core inner hole 51, hub mechanism 8 or driving part 2. In some embodiments, referring to FIG. 4, the tail end surface of the sliding sleeve 82 protrudes from the tail end surface of the sliding sleeve core 83, that is, there is a certain height difference h between the tail end surface of the sliding sleeve 82 and the tail end surface of the sliding sleeve core 83, When the ejector rod 21 of the driving component 2 pushes the shaft hegemony mechanism 8, the ejector rod 21 first contacts the tail end surface of the sliding sleeve 82 and pushes the sliding sleeve 82 forward, and the sliding sleeve 82 and the sliding sleeve core 83 move relative to each other and shrink , To realize the unlocking, avoid the risk or failure caused by pushing the sliding sleeve core 83 and the sliding sleeve 82 at the same time, or pushing the sliding sleeve core 83 first.

Furthermore, it is difficult to achieve precise control during assembly of the tail end surface of the sliding sleeve 82 and the tail end surface of the sliding sleeve core 83. See FIG. The core 83 is threadedly connected. Specifically, the tail of the sliding sleeve core 83 is provided with a screw hole, and the adjusting member 87 is connected to the screw hole. The end face of the tail. In this embodiment, the height difference between the tail end surface of the sliding sleeve 82 and the tail end surface of the sliding sleeve core 83 can be controlled by adjusting the screw depth of the adjusting member 87 in the screw hole, thereby facilitating the assembly of the entire structure.

In some embodiments, referring to FIG. 6, the stator 31 has multiple windings, and the multiple windings correspond to different rated speeds of the motor assembly 3. The motor can meet the requirements of multiple processing modes through the multi-winding motor, and multiple windings can freely switch multiple driving parameters through the driver to achieve continuous control. For example, in an embodiment where the two windings of the high-speed winding 33 and the low-speed winding 34 are provided, the output torque of the low-speed winding is about 54% higher than that of a single-winding motor of the same size, and the motor temperature is 10-15°C lower than that of a single-winding motor; Large torque meets the load required for machining blind holes, and the temperature of the motor is reduced, which can effectively reduce the elongation of the front end of the shaft system and meet the needs of machining blind hole depth accuracy.

The motor assembly 3 can be independent of the body 1 or integrated in the body 1. For example, in the embodiment shown in FIG. Cooling water jacket 12, the cooling liquid enters the body 1 from the cooling water jacket 12, and cools the motor assembly 3 and the air bearing, and finally discharges it to realize the synchronous cooling of the motor and the bearing. The working temperature of the electric spindle is more controllable and the accuracy is higher. , The life of the electric spindle is longer. Moreover, as the temperature of the motor is lowered, the elongation of the front end of the shafting can be effectively reduced to meet the requirements for the depth accuracy of the blind holes.

Among them, the motor assembly 3 can be located at one end of the shaft core 5 or at the middle position of the shaft core 5. For example, in the embodiment shown in FIG. The floating bearing 91 and the second air floating bearing 92, the first air floating bearing 91 and the second air floating bearing 92 are distributed on both sides of the motor assembly 3. The first air bearing 91 and the second air bearing 92 provide radial support for the shaft core 5 to improve the accuracy of the electric spindle.

The working principle of an embodiment of the present application is as follows: the air bearing and thrust bearing 4 support the shaft core 5 in a suspended state, then connect the main shaft and the cooling equipment inlet and outlet pipes, and finally connect the variable frequency drive and the main shaft motor connection, the motor assembly 3 drive shaft The core 5 runs at a high speed; the piston moves after the air cylinder is ventilated, and the tool clamping mechanism is pushed to release the tool 6. After the air is closed, the piston is reset by the spring, and the tool clamping mechanism clamps the tool 6 under the action of the elastic member 81.

Implementation process:

First connect clean compressed air to the floating state of the air bearing and supporting shaft 5;

Then connect the main shaft and the water inlet and outlet pipes of the cooling equipment;

Finally, connect the connection between the variable frequency drive and the spindle motor, and the motor drives the shaft core 5 to run;

Tool change 6: Vent the cylinder, and the cylinder forcefully pushes the tool clamping mechanism to release the tool 6; closes the ventilation, resets the cylinder, and clamps the tool 6 by the tool clamping mechanism (the cylinder and the tool clamping mechanism have no contact during the rotation of the shaft core 5).

The embodiments of the present application also provide a drilling rig, including the air-floating electric spindle in any of the above embodiments. That is, the tool clamped by the tool clamping mechanism is a drill. The drilling rig of the embodiment of the present application has the performance characteristics of low speed, high torque, low vibration, and low elongation; it can be applied to high-precision blind hole drilling in the PCB industry, and is mainly used for communications. Special drilling processing for all kinds of plates, such as backplanes, high multi-layer boards, blind buried holes, etc.

In the description of this specification, the description with reference to the terms "example", "embodiment" or "some embodiments" etc. means that a specific feature, structure, material or characteristic described in combination with the embodiment or example is included in at least the application. In one embodiment or example. In this specification, the schematic representations of the above-mentioned terms do not necessarily refer to the same embodiment or example. Moreover, the described specific features, structures, materials or characteristics can be combined in any one or more embodiments or examples in a suitable manner.

Claims

A shaft core assembly of an electric spindle, including:

Shaft core with inner hole of shaft core;

The clamping mechanism includes a chuck inner core and a chuck sleeve, the chuck sleeve is connected to the end of the shaft core;

The hub mechanism includes a sliding sleeve and a sliding sleeve core, the sliding sleeve is arranged in the inner hole of the shaft core, the sliding sleeve is sleeved outside the sliding sleeve core, and the sliding sleeve has a tapered inner hole, so The sliding sleeve core has an outer conical surface matched with the tapered inner hole, and the sliding sleeve core is connected with the inner core of the chuck;

An elastic component is arranged between the sliding sleeve and the chuck sleeve, and the elastic component resists the sliding sleeve.
The electric spindle shaft core assembly according to claim 1, wherein a plurality of deformation grooves are provided on the sliding sleeve.
The electric spindle shaft assembly according to claim 1, wherein the outer peripheral surface of the tail of the sliding sleeve is provided with a limit stop ring, and the hub mechanism further comprises:

An elastic outer sleeve is sleeved on the outside of the sliding sleeve, and the elastic outer sleeve abuts against the limit stop ring.
The electric spindle shaft core assembly according to claim 1, wherein the tail end surface of the sliding sleeve protrudes from the tail end surface of the sliding sleeve core.
The electric spindle shaft assembly according to claim 5, wherein the tail of the sliding sleeve core is provided with an adjusting component, the adjusting component is threadedly connected with the sliding sleeve core, and the adjusting component sinks into the sliding sleeve Inside, the tail end surface of the sliding sleeve protrudes from the tail end surface of the adjusting component.
An air-floating electric spindle includes:

The body is provided with shaft holes and air flow channels;

The electric spindle shaft core assembly according to any one of claims 1 to 5, wherein the shaft core is inserted into the shaft hole, and a thrust flying disc is provided on the chuck sleeve;

In the driving part, an ejector rod is provided at the output end, and the ejector rod extends into the inner hole of the shaft core and is used to push the shaft hegemony mechanism;

The motor assembly includes a stator and a rotor, and the rotor is connected to the shaft core;

An air bearing is arranged in the shaft hole and is matched with the shaft core;

Thrust bearing, matched with the thrust flying disc;

Wherein, the air bearing and the thrust bearing both have exhaust holes connected to the air flow channel.
The air-floating electric spindle according to claim 6, wherein the stator has a plurality of windings, and the plurality of windings correspond to different rated speeds of the motor components.
The air-floating electric spindle according to claim 6, wherein the stator is located in the shaft hole, the stator is connected to the body, and the body is provided with a cooling water jacket outside the shaft hole.
The air-floating electric spindle according to claim 8, wherein the air-floating bearing comprises a first air-floating bearing and a second air-floating bearing, and the first and second air-floating bearings are distributed in the motor Both sides of the component.
A drilling rig, comprising the air-floating electric spindle according to any one of claims 6-9.