Electric spindle and machine tool

Abstract

The motorized spindle comprises a machine body, a stator assembly and a shaft core assembly, the machine body is provided with a machine body inner hole extending in the axial direction, the stator assembly comprises a stator outer sleeve and a stator arranged in the stator outer sleeve, the stator outer sleeve is arranged at the rear end of the machine body, a top cover is arranged at the rear end of the stator outer sleeve, and the shaft core assembly is arranged in the top cover. The shaft core assembly comprises a shaft core, the front portion of the shaft core is supported in an inner hole of the machine body through a bearing, the rear portion of the shaft core penetrates into the stator outer sleeve and is provided with a rotor matched with the stator, and the stator assembly is provided with an air inlet hole extending forwards from the top cover. The air inlet forms a first air path and a second air path in the middle of the motorized spindle, the first air path enters from a front end gap between the stator and the rotor and is exhausted from the damping hole of the top cover, and the second air path extends to the front end of the motorized spindle from the outer wall of the inner hole of the machine body. The bearing and a cooling system of the motor are separated, mutual influence of heat is avoided, and the cooling effect is improved.

Description

Technical Field

[0001] The utility model is used in the field of processing equipment, in particular to an electric spindle and a machine tool. Background Art

[0002] With the improvement and popularization of automation level, the grinding and polishing industry is gradually replaced by machines to realize the process of automated processing. The electric spindle is one of the most important core components in the grinding and polishing industry. It is mainly used in castings, machined parts, welded parts, etc. The materials for grinding include steel parts, aluminum parts, plastics, etc.

[0003] The existing electric spindle generally adopts the structural design form of the motor being placed in the middle, that is, the motor structure is set between the bearings at both ends of the spindle. The heat of the electric spindle motor in this structural form accumulates inside the spindle, which will have an adverse effect on the bearings on both sides. At the same time, the existing electric spindle generally adopts the cooling method of connecting the motor and the bearing in series, that is, the cooling medium flows through the motor and the bearing in sequence. This cooling method inevitably leads to mutual influence between the heat of the motor and the bearing, and the cooling effect is poor. Utility Model Content

[0004] The utility model aims to solve at least one of the technical problems existing in the prior art and provides an electric spindle and a machine tool.

[0005] The technical solution adopted by the utility model to solve its technical problems is:

[0006] In a first aspect, an electric spindle comprises a body, a stator assembly and a shaft core assembly, wherein the body is provided with an inner body hole extending in an axial direction, the stator assembly comprises a stator housing and a stator arranged inside the stator housing, the stator housing is arranged at the rear end of the body, the rear end of the stator housing is provided with a top cover, the shaft core assembly comprises a shaft core, the front portion of the shaft core is supported by the inner body hole through a bearing, the rear portion of the shaft core penetrates into the stator housing, and is provided with a rotor cooperating with the stator, the stator assembly is provided with an air inlet extending forward from the top cover, the air inlet forms a first air path and a second air path in the middle of the electric spindle, the first air path enters through the front end gap between the stator and the rotor, and is discharged from the damping hole of the top cover, and the second air path extends from the outer wall of the inner body hole to the front end of the electric spindle.

[0007] In combination with the first aspect, in certain implementations of the first aspect, an inner cavity is formed inside the stator outer casing at the front ends of the rotor and the stator, the air inlet extends forward along the stator outer casing to the inner cavity, and the second air path includes a plurality of axial holes opened on the outer wall of the body, and the axial holes form an opening connected to the inner cavity on the rear end face of the body.

[0008] In combination with the first aspect and the above-mentioned implementations, in some implementations of the first aspect, the plurality of axial holes are evenly distributed along the circumference of the body.

[0009] In combination with the first aspect and the above-mentioned implementations, in some implementations of the first aspect, an end cover is provided at the front end of the body, a bearing cover is provided at the front end of the shaft core, and a labyrinth sealing structure is formed between the end cover and the bearing cover.

[0010] In combination with the first aspect and the above-mentioned implementations, in some implementations of the first aspect, the front end of the second gas path is connected to the labyrinth sealing structure.

[0011] In combination with the first aspect and the above-mentioned implementations, in some implementations of the first aspect, the bearing includes a front bearing and a rear bearing, and a bearing spacer is provided between the front bearing and the rear bearing.

[0012] In combination with the first aspect and the above-mentioned implementations, in some implementations of the first aspect, the top cover is provided with a filter element installation groove at the outer end of the damping hole, and a filter element is provided in the filter element installation groove.

[0013] In combination with the first aspect and the above-mentioned implementations, in some implementations of the first aspect, the body and the stator housing are manufactured separately, and the stator housing is sleeved on the rear end of the body.

[0014] In combination with the first aspect and the above-mentioned implementations, in some implementations of the first aspect, the shaft core adopts a solid structure, and a tool handle mounting hole is provided at the front end of the shaft core.

[0015] In a second aspect, a machine tool comprises the electric spindle described in any implementation of the first aspect.

[0016] One of the above technical solutions has at least one of the following advantages or beneficial effects:

[0017] In the technical solution of the utility model, a rear-mounted driving motor structure is adopted, the top cover is connected to the stator jacket for fixing and sealing, the stator and the stator jacket are matched and fixed, the rotor is installed at the rear end of the shaft core and then installed in the stator. Compared with the traditional front-mounted driving structure, the assembly is simple and the maintenance is convenient, and the heat generated by the motor has less impact on the bearing.

[0018] In the technical solution of the utility model, a new cooling air path system is adopted. The cooling air flow can enter from the top cover through the air inlet hole and be divided at the middle position of the electric spindle. The first air path takes away the heat through the gap between the stator and rotor at the rear end and flows out from the damping hole at the top cover. The second air path cools the bearing part by flowing through the machine body. The cooling systems of the bearing and the motor are separated to avoid mutual influence of heat and improve the cooling effect.

[0019] Additional aspects and advantages of the present invention will be given in part in the following description, and in part will become apparent from the following description, or will be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0021] Figure 1 The utility model is a schematic structural diagram of an embodiment of the electric spindle. DETAILED DESCRIPTION

[0022] This section will describe in detail the specific embodiments of the utility model. The preferred embodiments of the utility model are shown in the accompanying drawings. The purpose of the accompanying drawings is to supplement the description of the text part of the specification with graphics, so that people can intuitively and vividly understand each technical feature and the overall technical solution of the utility model, but it cannot be understood as a limitation on the protection scope of the utility model.

[0023] In the present invention, if directions (up, down, left, right, front and back) are described, it is only for the convenience of describing the technical solution of the present invention, and does not indicate or imply that the technical features referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, it cannot be understood as a limitation on the present invention.

[0024] In the present utility model, "several" means one or more, "multiple" means more than two, "greater than", "less than", "exceed" and the like are understood to exclude the number itself; "above", "below", "within" and the like are understood to include the number itself. In the description of the present utility model, if there is a description of "first" or "second", it is only used for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0025] In the present invention, unless otherwise clearly defined, the words "set", "install", "connect" and the like should be understood in a broad sense, for example, they can be directly connected or indirectly connected through an intermediate medium; they can be fixedly connected or detachably connected or integrally formed; they can be mechanically connected or electrically connected or able to communicate with each other; they can be the internal connection of two elements or the interaction relationship between two elements. Those skilled in the art can reasonably determine the specific meanings of the above words in the present invention in combination with the specific content of the technical solution.

[0026] in, Figure 1 The reference direction coordinate system of the embodiment of the utility model is given below. Figure 1 The embodiment of the utility model is described with reference to the direction shown.

[0027] The embodiment of the utility model provides an electric spindle, which can be used in industries such as machining, grinding and polishing.

[0028] See also Figure 1 The electric spindle includes a body 100, a stator assembly 200 and a shaft core assembly 300. The body 100 is provided with an inner hole extending in the axial direction, and the inner hole is used to arrange the shaft core assembly 300. The stator assembly 200 includes a stator housing 201 and a stator 200 arranged inside the stator housing 201. The stator housing 201 is arranged at the rear end of the body 100. The rear end of the stator housing 201 is provided with a top cover 202. The top cover 202 blocks the rear end of the stator housing 201 and is provided with a joint. The shaft core assembly 300 includes a shaft core 301. The front part of the shaft core 301 is connected by a bearing. Supported by the inner hole of the machine body, the rear part of the shaft core 301 penetrates the stator housing 201, and is provided with a rotor 302 matched with the stator 200, and the rotor 302 is connected to the shaft core 301 by interference fit or the like, and the stator assembly 200 is provided with an air inlet 203 extending forward from the top cover 202, and the air inlet 203 is divided into a first air path 204 and a second air path in the middle of the electric spindle, and the first air path 204 enters from the front end gap between the stator 200 and the rotor 302, and is discharged from the damping hole 205 of the top cover 202, and the second air path extends from the outer wall of the inner hole of the machine body to the front end of the electric spindle. The function of the damping hole 205 is to provide exhaust damping for the first air path 204, so as to better distribute the cooling gas flowing to the first air path 204 and the second air path.

[0029] In the technical solution of the utility model, a rear-mounted driving motor structure is adopted, the top cover 202 is connected to the stator housing 201 for fixing and sealing, the stator 200 is fixed with the stator housing 201, the rotor 302 is installed at the rear end of the shaft core 301, and then installed in the stator 200. Compared with the traditional front-mounted driving structure, the assembly is simple and the maintenance is convenient, and the heat generated by the motor has less impact on the bearing.

[0030] In the technical solution of the present invention, a new cooling air path system is adopted. The cooling air flow can enter from the top cover 202 through the air inlet 203 and be divided at the middle position of the electric spindle. The first air path 204 takes away its heat through the gap between the stator and rotor 302 at the rear end and flows out from the damping hole 205 at the top cover 202. The second air path cools the bearing part by flowing through the body 100. The cooling systems of the bearing and the motor are separated to avoid mutual influence of heat and improve the cooling effect.

[0031] In some embodiments, see Figure 1The stator jacket 201 forms an irregular inner cavity 206 at the front end of the rotor 302 and the stator 200. The air inlet 203 extends forward along the stator jacket 201 to the inner cavity 206. The air inlet 203 forms an interface on the top cover 202, and a joint is provided at the interface. The second air path includes a plurality of axial holes 101 opened on the outer wall of the body 100. The axial holes 101 form an opening 102 connected to the inner cavity 206 on the rear end face of the body 100. The cooling gas can enter the air inlet 203 through the joint, and is introduced into the inner cavity 206 along the air inlet 203 and the stator jacket 201. The cooling gas is divided at the inner cavity 206. Part of the air flow flows backward along the gap between the stator and the rotor 302 to take away its heat, and finally flows out from the damping hole 205 at the top cover 202. Part of the airflow flows along the inner cavity 206 and is distributed to the multiple axial holes 101 to flow forward, taking away the heat of the bearings inside the body 100, and finally overflowing from the front end of the electric spindle.

[0032] For further information, see Figure 1 A plurality of axial holes 101 are evenly distributed along the circumference of the body 100 to provide more uniform cooling for the bearing.

[0033] For further information, see Figure 1 An end cover 103 is provided at the front end of the body 100, which is connected to the body 100 and locks the outer ring of the bearing. A bearing pressure cover 303 is provided at the front end of the shaft core 301, which locks the inner ring of the bearing. A labyrinth sealing structure 104 is formed between the end cover 103 and the bearing pressure cover 303 to prevent external liquids, impurities, etc. from entering the interior of the electric spindle.

[0034] For further information, see Figure 1 The front end of the second gas path is connected to the labyrinth sealing structure. With the help of the airflow for cooling the bearing, a gas seal is formed at the labyrinth sealing structure, further improving the sealing effect and preventing external liquids, impurities, etc. from entering the interior of the electric spindle.

[0035] In some embodiments, see Figure 1 The bearing includes a front bearing 304 and a rear bearing 305 , and a bearing spacer 306 is provided between the front bearing 304 and the rear bearing 305 .

[0036] In some embodiments, see Figure 1 In order to better control the exhaust damping of the damping hole 205, the top cover 202 is provided with a filter element installation groove 207 at the outer end of the damping hole 205, and a filter element 208 is provided in the filter element installation groove 207. The filter element 208 is locked inside the filter element installation groove 207 by a pressure ring 209.

[0037] In some embodiments, see Figure 1The body 100 and the stator housing 201 are made separately, and the stator housing 201 is sleeved on the rear end of the body 100. In this embodiment, the body 100, the stator housing 201, the shaft core assembly 300, the body 100, and the stator assembly 200 are separately arranged to form a segmented structure. The entire electric spindle is mainly composed of these three parts, and only these three parts need to be assembled. This structure is easy to assemble and maintain, and saves labor.

[0038] In some embodiments, see Figure 1 The shaft core 301 adopts a solid structure, and the front end of the shaft core 301 is provided with a tool handle mounting hole 307. Different from the traditional hollow shaft core 301, the shaft core 301 in this embodiment adopts a solid structure, which greatly enhances its bearing capacity under heavy load conditions.

[0039] The embodiment of the utility model also provides a machine tool, including the electric spindle in any of the above embodiments. The electric spindle has strong adaptability, simple and practical structure, easy assembly and maintenance, low labor input cost, high spindle cost performance, and high market competitiveness.

[0040] In the description of this specification, the description with reference to the terms "example", "embodiment" or "some embodiments" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0041] Of course, the invention is not limited to the above-mentioned embodiments, and those skilled in the art may make equivalent modifications or substitutions without violating the spirit of the invention, and these equivalent modifications or substitutions are all included in the scope defined by the claims of this application.

Claims

1. An electric spindle, characterized in that: The invention comprises a machine body, a stator assembly and an axis core assembly, wherein the machine body is provided with an inner hole of the machine body extending in the axial direction, the stator assembly comprises a stator outer shell and a stator arranged inside the stator outer shell, the stator outer shell is arranged at the rear end of the machine body, the rear end of the stator outer shell is provided with a top cover, the axis core assembly comprises an axis core, the front part of the axis core is supported in the inner hole of the machine body by a bearing, the rear part of the axis core penetrates into the stator outer shell, and a rotor matched with the stator is provided, the stator assembly is provided with an air inlet extending forward from the top cover, the air inlet forms a first air path and a second air path in the middle part of the electric spindle, the first air path enters through the front end gap between the stator and the rotor, and is discharged from the damping hole of the top cover, and the second air path extends from the outer wall of the inner hole of the machine body to the front end of the electric spindle.

2. The electric spindle according to claim 1, characterized in that: The interior of the stator casing forms an inner cavity at the front end of the rotor and the stator, the air inlet extends forward along the stator casing to the inner cavity, and the second air path includes a plurality of axial holes opened on the outer wall of the body, and the axial holes form an opening connected to the inner cavity on the rear end face of the body.

3. The electric spindle according to claim 2, characterized in that: The plurality of axial holes are evenly distributed along the circumference of the body.

4. The electric spindle according to claim 1, characterized in that: An end cover is provided at the front end of the machine body, a bearing cover is provided at the front end of the shaft core, and a labyrinth sealing structure is formed between the end cover and the bearing cover.

5. The electric spindle according to claim 4, characterized in that: The front end of the second gas path is connected to the labyrinth sealing structure.

6. The electric spindle according to claim 1, characterized in that: The bearing comprises a front bearing and a rear bearing, and a bearing spacer is arranged between the front bearing and the rear bearing.

7. The electric spindle according to claim 1, characterized in that: The top cover is provided with a filter element installation groove at the outer end of the damping hole, and a filter element is provided in the filter element installation groove.

8. The electric spindle according to claim 1, characterized in that: The machine body and the stator housing are manufactured separately, and the stator housing is sleeved on the rear end of the machine body.

9. The electric spindle according to claim 1, characterized in that: The shaft core adopts a solid structure, and a tool handle mounting hole is arranged at the front end of the shaft core.

10. A machine tool, characterized in that: The invention comprises the electric spindle according to any one of claims 1 to 9.

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