CN113579269A

CN113579269A - High-speed electric spindle without coupler

Info

Publication number: CN113579269A
Application number: CN202110901930.4A
Authority: CN
Inventors: 刘观煊
Original assignee: Xiamen Deenshi Technology Co ltd
Current assignee: Xiamen Deenshi Technology Co ltd
Priority date: 2021-08-06
Filing date: 2021-08-06
Publication date: 2021-11-02
Anticipated expiration: 2041-08-06
Also published as: CN113579269B

Abstract

The invention discloses a high-speed electric spindle without a coupler, which comprises: a housing; the motor assembly is positioned at the tail end of the shell and is arranged in the shell; the motor assembly comprises a stator and a rotor, and the rotor is arranged inside the stator and can rotate relative to the stator; one end of the shaft core is fixed in the rotor, so that the shaft core integrally rotates along with the rotor, the other end of the shaft core extends out of the shell from the front end of the shell, and the end is used for connecting a machining tool; the high-speed electric spindle without the coupler adopts the integrated design of the motor shaft core, can greatly improve the rotating speed, does not generate vibration due to the unbalance amount of the high-speed rotation of the coupler, also saves the need of installing a bearing on a motor assembly, reduces the cost, prolongs the service life of the spindle, has an air path penetrating through the whole shell, can take away the heat generated by the motor and the bearing, simultaneously does not allow air flow to enter the motor and the bearing, and has low requirement on the cleanliness of the air flow.

Description

High-speed electric spindle without coupler

Technical Field

The invention relates to the field of high-speed motor spindles, in particular to a high-speed motor spindle without a coupler.

Background

The high-speed main shaft is a part commonly used in the processing field, the rotary torque of a motor is transmitted to a main shaft core through a coupler of some main shafts, the coupler is abraded, the dynamic balance difference is generated at high rotating speed, and the coupler generates larger noise at high rotating speed of the main shaft; high-speed electric spindles are new technologies which integrate a spindle with a spindle motor in recent years, but the current high-speed electric spindles require a whole set of auxiliary devices including an oil mist lubricator, a cooling device and the like, wherein the cooling device requires a set of expensive air filtering device in order to keep air flow clean, so that the cost of the high-speed electric spindle is extremely high.

Disclosure of Invention

The purpose of the invention is as follows: in order to overcome the defects in the prior art, the invention provides the high-speed electric spindle without the coupler, which has low cost and low noise during high-speed operation.

The technical scheme is as follows: in order to achieve the above object, the present invention provides a high-speed electric spindle without a coupling, comprising:

a housing;

the motor assembly is positioned at the tail end of the shell and is arranged in the shell; the motor assembly comprises a stator and a rotor; the rotor is arranged inside the stator and can rotate relative to the stator;

a shaft core having a connection end fixed inside the rotor, the connection end causing the shaft core to integrally rotate with the rotor; the tool holder further comprises a protruding end protruding out of the housing from the front end of the housing, and the protruding end is used for connecting a machining tool.

Furthermore, the shell is internally provided with an air path, so that air can flow in from the tail end of the shell and is discharged from the front end of the shell to generate an air curtain, and the air curtain is dustproof and liquid-proof, so that heat generated by components in the shell is discharged.

Furthermore, the shaft core is also provided with a middle shaft section positioned between the connecting end and the extending end, and the middle shaft section is arranged in the shell; the gas circuit includes a first annular air gap disposed about the motor assembly and a second annular air gap disposed about the intermediate shaft segment.

Further, the motor assembly further comprises a motor shell, and the motor shell and the shell are fixed to each other; the stator is fixed inside the motor shell;

the motor assembly is provided with a sealing device for isolating external air; the first annular air gap is between the motor casing and an inner wall of the housing.

Further, the gas circuit further comprises a third annular air gap between the stator and the rotor; the air flow entering from the tail end of the shell is divided into two parts which respectively flow through the first annular air gap and the third annular air gap.

Further, a bearing assembly is arranged between the middle shaft section and the shell;

the bearing assembly comprises a first bearing located in the middle of the housing and a second bearing located at the front end of the housing;

a support component is arranged between the first bearing and the second bearing and can support the inner ring and the outer ring of the first bearing and the second bearing;

the second annular air gap is between the support assembly and an inner wall of the housing.

Further, a connecting passage for connecting the first annular air gap and the second annular air gap is arranged on the shell; and a plurality of exhaust grooves arranged around the second bearing are further arranged in the shell, and the exhaust grooves are communicated with the second annular air gap.

Furthermore, a dustproof cover is mounted at the front end of the shaft core, and an annular groove is formed in the end face, facing the shell, of the dustproof cover; the front end of the shell is provided with an annular part extending into the annular groove; air gaps are arranged between the outer surface of each side of the annular part and the corresponding groove surface of the annular groove.

Further, the support assembly includes:

a first support ring, an end surface of which is in contact with an outer ring of the first bearing;

a second support ring, the end surface of which is in contact with the outer ring of the second bearing;

the elastic element is arranged between the first support ring and the second support ring and can enable the first support ring and the second support ring to generate pretightening force;

an inner support ring disposed between the inner race of the first bearing and the inner race of the second bearing.

Further, the motor assembly further includes a rotation speed detecting element for detecting a rotation speed of the rotor.

Further, the connecting part is also included, and the connecting part can be a part of the shell or an independent part which is independent from the shell and is fixed relative to the shell; the connecting part is provided with a connecting structure for connecting a machine tool spindle.

Has the advantages that: the high-speed electric spindle without the coupler adopts the integrated design of the motor shaft core, can greatly improve the rotating speed, does not generate vibration due to the unbalance amount of the high-speed rotation of the coupler, saves a bearing which is required to be installed by a motor assembly, reduces the cost and prolongs the service life of the spindle; in addition, the high-speed electric spindle without the coupler is provided with an air path penetrating through the whole shell, heat generated by the motor and the bearing can be taken away, air flow cannot enter the motor and the bearing, and the requirement on air flow cleanliness is low.

Drawings

Fig. 1 is an overall structure diagram of a high-speed electric spindle without a coupling according to a first embodiment;

FIG. 2 is a structural view of the middle part of the high-speed electric spindle without a coupling according to the first embodiment;

FIG. 3 is a structural view of a high-speed electric spindle head without a coupling according to a first embodiment;

FIG. 4 is a first perspective layout view of the exhaust groove of the first embodiment;

FIG. 5 is a second perspective view of the exhaust groove of the first embodiment;

FIG. 6 is a partial structure view of a high-speed electric spindle without a coupling according to a second embodiment;

FIG. 7 is a structural view of a high-speed electric spindle without a coupling with a connecting part in a third embodiment;

fig. 8 is a structural view of another high-speed electric spindle without a coupling with a connecting part in the third embodiment.

In the figure: 1-a shell; 11-a cover body; 12-tail cover body; 121-an air inlet; 13-a ring-shaped portion; 2-a motor assembly; 21-a stator; 211-stator core; 212-stator coils; 22-a rotor; 23-a motor housing; 24-a rotational speed detection element; 25-motor compression nut; 3-an axial core; 4-a bearing assembly; 41-a first bearing; 42-a second bearing; 43-a support assembly; 431-a first support ring; 432-a second support ring; 433-an elastic element; 434-inner support ring; 51-a first locking nut; 52-a second lock nut; 6, a dustproof cover; 61-ring groove; 7-gas path; 71-a first annular air gap; 72-second annular air gap; 73-connecting path; 74-an exhaust groove; 731-groove; 732-a first air hole; 733-second vent; 74-an exhaust groove; 75-a third annular air gap; 81-a first sealing ring; 82-a second sealing ring; 9-cable fixing head; 10-a connecting part; 101-connecting structure.

Detailed Description

The present invention will be further described with reference to the accompanying drawings.

First embodiment

The high-speed electric spindle without a coupling shown in the attached figures 1-3 comprises a shell 1, a motor assembly 2 and a shaft core 3.

The motor assembly 2 is positioned at the tail end of the shell 1 and is installed inside the shell 1; the motor assembly 2 includes a stator 21, a rotor 22, a motor housing 23, and a rotation speed detecting element 24.

The rotor 22 is arranged inside the stator 21 and can rotate relative to the stator 21; the motor shell 23 is fixed with the shell 1 through a motor compression nut 25, and the stator 21 is fixed inside the motor shell 23; the rotational speed detecting element 24 is configured to detect a rotational speed of the rotor 22; the stator 21 includes a stator core 211 fixedly coupled to the motor housing 23, and a stator coil 212 wound around the stator core 211.

A tail cover body 12 is fixedly mounted at the tail of the shell 1, a cable fixing head 9 is fixedly mounted on the tail cover body 12, a power line and a signal line required by the integral operation of the electric spindle are fixed on the tail cover body 12 through the cable fixing head 9, and the power line and the signal line are respectively connected with the stator 21 and the rotating speed detection element 24.

The shaft core 3 has a connection end fixed inside the rotor 22, and the connection end enables the shaft core 3 to integrally rotate with the rotor 22; the shaft core 3 is also provided with a protruding end which protrudes out of the shell 1 from the front end of the shell 1 and is used for connecting a processing tool; in this embodiment, the shaft core 3 and the rotor 22 of the motor assembly 2 are connected in an integrated manner, a coupler is not required, the rotating speed can be greatly increased, vibration due to unbalance of high-speed rotation of the coupler is avoided, and the service life of the electric spindle can be greatly prolonged. In addition, due to the adoption of a coupler-free design, the electric spindle with the same power has a compact integral structure and a small volume, and can be installed in a smaller installation space.

Preferably, the shaft core 3 is further provided with an intermediate shaft section located between the connecting end and the extending end, and the intermediate shaft section is placed in the shell 1; a bearing assembly 4 is arranged between the middle shaft section and the shell 1; the bearing assembly 4 comprises a first bearing 41 located in the middle of the housing 1 and a second bearing 42 located at the front end of the housing 1; the number of the first bearings 41 and the second bearings 42 can be respectively configured to be 1-2 according to the requirement, and in the embodiment shown in fig. 1, the number of the first bearings 41 is 1, and the number of the second bearings is two. A support assembly 43 is disposed between the first bearing 41 and the second bearing 42, and the support assembly 43 can support the inner and outer rings of the first bearing 41 and the second bearing 42.

The support assembly 43 includes a first support ring 431, a second support ring 432, and an elastic element 433, an end surface of the first support ring 431 is in contact with an outer ring of the first bearing 41; the end face of the second support ring 432 is in contact with the outer race of the second bearing 42; an elastic element 433 is disposed between the first support ring 431 and the second support ring 432, so as to generate a pre-tightening force between the first support ring 431 and the second support ring 432; an inner support ring 434 is provided between the inner race of the first bearing 41 and the inner race of the second bearing 42.

Through the structure, the rotor 22 is fixed on the connecting end of the shaft core 3 in a sleeved mode, and therefore the shaft core 3 is stably supported relative to the shell 1 by the first bearing 41 and the second bearing 42, the rotor 22 can be coaxially and stably installed relative to the shell 1, a bearing is not needed to be additionally arranged on the rotor 22, namely the motor assembly 2 does not comprise the bearing, the bearing which needs to be installed on the motor assembly originally can be omitted, and cost is reduced.

Preferably, the tail cover 12 is provided with an air inlet 121, and the housing 1 is provided with an air passage 7 therein, so that air can flow in from the tail end of the housing 1 and be exhausted from the front end of the housing 2, so as to exhaust heat generated by components in the housing 1 (including heat generated by the motor and heat generated by the first bearing 41 and the second bearing 42 when the shaft core 3 rotates at a high speed). The air inlet of the air path 7 is arranged at the tail end of the shell 1, the air outlet is arranged at the front end of the shell 1, the air path 7 penetrates through the whole shell 1, air can pass around the heating element, and heat of the heating element is taken away to the maximum extent. The air inlet 121 is connected with an air source through an air pipe, and the air source injects air into the shell 1 through the air inlet 121, so that flowing air flow always exists in the shell 1.

The air passage 7 comprises a first annular air gap 71 arranged around the motor assembly 2 and a second annular air gap 72 arranged around the intermediate shaft section; the motor assembly 2 has a sealing device for isolating external air; the first annular air gap 71 is between the motor casing 23 and the inner wall of the housing 1; the sealing device isolates the interior of the motor component from air flow, and the air flow cannot pass through the interior of the motor, so that the air flow cannot bring impurities into the interior of the motor component.

The second annular air gap 72 is between the support assembly 43 and the inner wall of the housing 1. Both the first bearing 41 and the second bearing 42 themselves have a sealing structure to prevent the air flow passing between the inner and outer races of the bearings from entraining foreign matter into the interior of the bearings.

The housing 1 is provided with a connecting passage 73 connecting the first annular air gap 71 and the second annular air gap 72; as shown in fig. 2, the connecting passage 73 includes a groove 731 formed on the outer side of the housing 1, and a first air hole 732 and a second air hole 733 respectively connected to two ends of the groove, the first air hole 732 and the second air hole 733 are respectively connected to the first annular air gap 71 and the second annular air gap 72, the groove 731 is milled on the outer wall of the housing 1, and the cover 11 for isolating the groove 731, the first air hole 732, and the second air hole 733 from the outside is fixed on the housing 1, so that the processing cost of the connecting passage 73 is low, and the connecting passage 73 is formed in the wall thickness range of the housing 1, and does not occupy additional space.

In the embodiment shown in fig. 1, a first sealing ring 81 is disposed between the outer ring of the first bearing 41 and the housing 1, and the first sealing ring 81 is used for isolating air so that the air passes through the connecting passage 73. A second sealing ring 82 is arranged between the first support ring 431 and the inner wall of the second support ring 432, and can isolate air, so that the air passes through the second annular air gap 72 (namely, the outer side of the second support ring 432), thereby ensuring that the air flow does not pass through the inside of the bearing, reducing the requirement on the cleanliness of a compressed air source greatly, and simultaneously generating an air curtain to protect a bearing assembly from being polluted by the outside.

Preferably, a plurality of exhaust grooves 74 are further disposed in the housing 1 and surround the second bearing 42, the exhaust grooves 74 are communicated with the second annular air gap 72, as shown in the embodiment shown in fig. 3, the exhaust grooves 74 are formed on the inner wall of the housing 1 and extend along the axial direction of the second bearing 42, the exhaust grooves 74 may also be inclined or threaded, the number of the exhaust grooves 74 may be multiple as required, all the exhaust grooves 74 are disposed in a circumferential array around the second bearing 42, as shown in the embodiment shown in fig. 4 to 5, 4 exhaust grooves 74 are disposed, so that the processing is simple, the cost is saved, and the mounting accuracy of the second bearing 42 is not affected, and the heat generated by the second bearing 42 can be taken away by the air passing through the exhaust grooves 74.

Preferably, as shown in fig. 3, a dust cover 6 is mounted at the front end of the shaft core 3, and an annular groove 61 is formed on an end surface of the dust cover 6 facing the housing 1; the front end of the shell 1 is provided with an annular part 13 extending into the annular groove 61; by adopting the structure, the air flow channel formed by connecting the air gaps between the annular part 13 and the annular groove 61 has multiple turns, and the air flow in the shell 1 can be smoothly discharged, and meanwhile, liquid such as dust, cutting oil and the like can be effectively prevented from entering the shell 1 when the electric spindle is idle or used.

By adopting the design of the gas circuit 7, the heat generated by the motor assembly and the bearing assembly can be taken away by fully utilizing the airflow of the compressed air, the spindle oil cooler is not needed, meanwhile, the airflow can also generate an air curtain to protect the bearing assembly from being polluted by the outside, the inside of the motor assembly and the bearing assembly are isolated by the sealing design, so that the inside of the motor assembly and the ball of the inner ring of the bearing are isolated from the airflow of the compressed air, and the airflow can not pass through the inside of the motor and the inside of the bearing, so that the requirement on the cleanliness of a compressed air source is greatly reduced.

Preferably, a first lock nut 51 contacting with the inner ring of the first bearing 41 is fixed on the shaft core 3; a second lock nut 52 contacting with the outer ring of the second bearing 42 is fixed to the head of the housing 1, so that the bearing can be fixed, and the structural stability can be increased.

Second embodiment

In this embodiment, the structure of the high-speed electric spindle without a coupling is substantially the same as that of the first embodiment, and the only difference is that in this embodiment, the motor assembly 2 is a non-completely sealed structure, and the air path 7 further includes a third annular air gap 75 located between the stator 21 and the rotor 22; the air flow entering from the rear end of the housing 1 is divided into two parts and flows through the first annular air gap 71 and the third annular air gap 75, respectively, as shown in fig. 6. In addition, a small amount of air may pass through the gap between the inner ring and the outer ring of the first bearing 41 and the second bearing 42 or the gap between the inner ring and the shaft core 3, in this embodiment, since the air flow may pass through the inside of the motor assembly 2 and the inner ring of the bearing, a better heat dissipation effect can be obtained than in the first embodiment, and accordingly, the requirement on cleanliness of the air flow is relatively high, and the introduced air flow needs to be pre-filtered.

Third embodiment

The present embodiment is based on the first embodiment or the second embodiment, and the structure thereof is basically the same as the above embodiments, except that the electric spindle of the present embodiment further includes a connecting portion 10 for connecting a spindle of a machine tool, where the connecting portion 10 may be a part of the housing 1, or may be a separate component which is independent from the housing 1 and fixed with respect to the housing 1, and in the latter case, the connecting portion 10 is a sleeve body which sleeves a part or all of the housing 1 (as shown in fig. 7). The connecting portion 10 has a connecting structure 101, and the form of the connecting structure 101 may be a tool shank form, a flange plate and other common structural forms for connecting a main shaft of a machine tool, and may also be other connecting forms, including a main shaft connecting form emerging in the future, which should also be regarded as falling within the scope of the present invention. When the connecting structure 101 is in the form of a tool shank, the connecting structure can be an HSK tool shank as shown in fig. 7 or a 7:24 tool shank as shown in fig. 8, so that the electric spindle can be mounted on the spindles of various machine tools as a spindle speed increasing head through the connecting structure 101.

The cable connected to the motor module 2 is led out from the side of the connection portion 10 to the outside of the connection portion 10, and the air path leading to the air inlet 121 may be led out from the side of the connection portion 10 or from the rear end of the connection structure 101.

The high-speed electric spindle without the coupler adopts the integrated design of the motor shaft core, can greatly improve the rotating speed, does not generate vibration due to the unbalance amount of the high-speed rotation of the coupler, saves a bearing which is required to be installed by a motor assembly, reduces the cost and prolongs the service life of the spindle; in addition, the high-speed electric spindle without the coupler is provided with an air path penetrating through the whole shell, heat generated by the motor and the bearing can be taken away, air flow cannot enter the motor and the bearing, and the requirement on air flow cleanliness is low.

The above description is only of the preferred embodiments of the present invention, and it should be noted that: it will be apparent to those skilled in the art that various modifications and adaptations can be made without departing from the principles of the invention and these are intended to be within the scope of the invention.

Claims

1. A high-speed electric spindle without a coupling, comprising:

a housing (1);

a motor assembly (2) which is positioned at the tail end of the shell (1) and is arranged inside the shell (1); the motor assembly (2) comprises a stator (21) and a rotor (22); the rotor (22) is arranged inside the stator (21) and can rotate relative to the stator (21);

a shaft core (3) having a connection end fixed inside the rotor (22), the connection end causing the shaft core (3) to integrally rotate with the rotor (22); the tool is characterized by further comprising a protruding end protruding out of the shell (1) from the front end of the shell (1), and the protruding end is used for being connected with a processing tool.

2. The high-speed electric spindle without the shaft coupling as claimed in claim 1, characterized in that the housing (1) has an air passage (7) therein, so that air can flow in from the rear end of the housing (1) and can be exhausted from the front end of the housing (2) to exhaust heat generated by components in the housing (1).

3. The high-speed electric spindle without coupling according to claim 2, characterized in that said spindle core (3) is further provided with an intermediate shaft section between said connection end and said protruding end, said intermediate shaft section being placed inside said housing (1); the air passage (7) comprises a first annular air gap (71) arranged around the motor assembly (2) and a second annular air gap (72) arranged around the intermediate shaft section.

4. The high-speed electric recoiling spindle without coupling of claim 3, wherein the motor assembly (2) further comprises a motor housing (23), the motor housing (23) and the housing (1) being fixed to each other; the stator (21) is fixed inside the motor shell (23);

the motor assembly (2) is provided with a sealing device for isolating air; the first annular air gap (71) is between the motor housing (23) and an inner wall of the housing (1).

5. The high-speed electric recoilless spindle according to claim 3, characterized in that said air circuit (7) further comprises a third annular air gap (75) between said stator (21) and said rotor (22); the air flow entering from the tail end of the shell (1) is divided into two parts and flows through the first annular air gap (71) and the third annular air gap (75) respectively.

6. The high-speed electric recoilless spindle according to claim 3, characterized in that a bearing assembly (4) is provided between said intermediate shaft section and said housing (1);

the bearing assembly (4) comprises a first bearing (41) located in the middle of the housing (1) and a second bearing (42) located at the front end of the housing (1);

a support component (43) is arranged between the first bearing (41) and the second bearing (42), and the support component (43) can support the inner ring and the outer ring of the first bearing (41) and the second bearing (42);

the second annular air gap (72) is between the support assembly (43) and an inner wall of the housing (1).

7. The high-speed electric recoiling spindle without coupling of claim 6, wherein the housing (1) is provided with a connecting passage (73) connecting the first annular air gap (71) and the second annular air gap (72); a plurality of exhaust grooves (74) arranged around the second bearing (42) are further arranged in the shell (1), and the exhaust grooves (74) are communicated with the second annular air gap (72).

8. The high-speed electric spindle without the shaft coupling of claim 7, characterized in that a dust cover (6) is installed at the front end of the spindle core (3), and an annular groove (61) is arranged on the end surface of the dust cover (6) facing the shell (1); the front end of the shell (1) is provided with an annular part (13) extending into the annular groove (61); air gaps are arranged between the outer surface of each side of the annular part (13) and the corresponding groove surface of the annular groove (61).

9. The high-speed electric recoiling spindle without coupling of claim 6, wherein the support assembly (43) comprises:

a first support ring (431) whose end face is in contact with an outer ring of the first bearing (41);

a second support ring (432) whose end face is in contact with an outer ring of the second bearing (42);

an elastic element (433) arranged between the first support ring (431) and the second support ring (432) and capable of generating pre-tightening force to the first support ring (431) and the second support ring (432);

an inner support ring (434) disposed between the inner race of the first bearing (41) and the inner race of the second bearing (42).

10. The high-speed electric recoilless spindle according to claim 1, characterized in that said motor assembly (2) further comprises a rotation speed detecting element (24), said rotation speed detecting element (24) being adapted to detect a rotation speed of said rotor (22).

11. A high-speed electric recoilless spindle according to any of claims 1-10, further comprising a connecting part (10), said connecting part (10) being either a part of the housing (1) or a separate part independent of the housing (1) and fixed relative to the housing (1); the connecting part (10) has a connecting structure (101) for connecting a machine tool spindle.