Spindle box hole system structure capable of axially positioning bearing

Abstract

The utility model provides a spindle box hole system structure capable of axially positioning a bearing. The main shaft box hole system structure capable of axially positioning the bearing comprises an axle box, an assembly hole system is formed in the axle box, and a main shaft body is arranged in the assembly hole system; the belt pulley is used for transmission and is arranged at one end of the main shaft body; the first bearing, the second bearing and the third bearing are used for supporting the main shaft body to rotate, and the main shaft body is fixedly sleeved with the first bearing, the second bearing and the third bearing; and the rear end cover and the front end cover are used for covering the assembly hole series. According to the spindle box hole system structure capable of axially positioning the bearing, the groove is machined in the hole system, and the front bearing axial positioning ring and the rear bearing axial positioning ring are installed to achieve necessary bearing axial positioning; according to the design, the assembly process is simplified, and the mounting precision of the bearing and the stability of the whole main shaft unit are improved.

Description

Technical Field

[0001] The utility model relates to the technical field of numerical control machine tools, in particular to a spindle box hole system structure capable of axially positioning a bearing. Background Art

[0002] In the design of CNC lathe spindle units, the support, rotation accuracy and stability of the spindle are crucial to the performance of the entire spindle unit. In particular, in terms of meeting national mandatory standards such as high precision, low temperature rise and long life, extremely high requirements are placed on the accuracy and installation accuracy of the spindle and its supporting bearings.

[0003] In the traditional spindle box hole system structure, the axial positioning of the spindle mainly depends on the hole shoulder and the end cover; this structure has some problems in the processing process; first, due to the existence of the hole shoulder, the hole system processing can only be carried out in a horizontal installation manner, which makes secondary clamping or turntable boring processes necessary, and these processes may introduce errors; secondly, since the hole system is in a horizontal state, the boring cutter is prone to fall due to its own weight during the processing, which further affects the coaxiality accuracy of the hole system.

[0004] However, due to the above factors, it is difficult to ensure the coaxiality accuracy of the spindle hole system in batch processing, and the surface roughness of the hole is difficult to meet the quality requirements; therefore, the assembled spindle unit may have problems such as abnormal temperature rise, short bearing life and excessive spindle assembly accuracy, which cannot meet the mandatory requirements of national standards; although some researchers have proposed some improvement plans, they are usually limited to adjusting the process flow or using more precise processing equipment, without fundamental structural design innovation; therefore, how to design a new spindle box hole system structure that can both ensure high precision and adapt to the needs of large-scale production has become an urgent problem to be solved. Utility Model Content

[0005] The utility model provides a spindle box hole system structure capable of axially positioning a bearing, in order to solve the problems of machining accuracy caused by the spindle axial positioning method in the traditional spindle box hole system structure proposed in the above background technology, and the technical problem of being unable to adapt to large-scale production.

[0006] The utility model provides a spindle box hole system structure capable of axially positioning the bearing, comprising: an axle box, the axle box being provided with an assembly hole system, a spindle body being arranged in the assembly hole system; a pulley for transmission, the pulley being arranged on one end of the spindle body; a first bearing, a second bearing and a third bearing for supporting the rotation of the spindle body, the first bearing, the second bearing and the third bearing being fixedly sleeved on the spindle body; a rear end cover and a front end cover for covering the assembly hole system, the rear end cover and the front end cover being respectively arranged at the two ends of the assembly hole system.

[0007] Preferably, the assembly hole system is provided with positioning grooves matched with the first bearing, the second bearing and the third bearing.

[0008] Preferably, both the rear end cover and the front end cover are provided with through openings, and the through openings are adapted to the main shaft body.

[0009] Preferably, the rear end cover and the front end cover are each provided with a plurality of mounting holes, and locking screws for limiting the rear end cover and the front end cover are arranged in the mounting holes, and the plurality of locking screws are all threadedly connected to the axle box.

[0010] Preferably, a sealing ring is provided in the through opening, and the sealing ring is an annular ring made of elastic material.

[0011] Preferably, a pin for limiting position is provided on the pulley, and a groove matching with the pin is provided on the main shaft body.

[0012] Preferably, a sensor for detecting the rotation state of the spindle body is arranged in the assembly hole system.

[0013] Compared with the related art, the spindle box hole system structure provided by the utility model for axial positioning of the bearing has the following beneficial effects:

[0014] The utility model provides a spindle box hole system structure capable of axially positioning the bearing:

[0015] By eliminating the hole shoulder used for axial positioning of the bearing in the traditional design, the entire hole system is designed as a through hole. This design allows the use of a more efficient vertical mill processing technology and avoids various problems that may occur in horizontal processing. During vertical mill processing, the spindle hole system is in a vertical direction, which can avoid deformation caused by the weight of the tool, and the full-length up and down processing also eliminates the errors caused by secondary clamping or turntable turning. At the same time, by machining grooves in the hole system and installing the front bearing axial locating ring and the rear bearing axial locating ring, the necessary bearing axial positioning is achieved. This design simplifies the assembly process and improves the installation accuracy of the bearing and the stability of the entire spindle unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A schematic diagram of a front cross-sectional structure of a preferred embodiment of a spindle box hole system structure capable of axially positioning a bearing provided by the utility model;

[0017] Figure 2 It is the assembly drawing of the main shaft and the axle box in the utility model;

[0018] Figure 3 It is a schematic diagram of the cross-sectional structure of a traditional axle box;

[0019] Figure 4This is the assembly drawing of the traditional spindle body and axle box.

[0020] Numbers in the figure: 1, axle box; 2, main shaft body; 3, pulley; 4, first bearing; 5, rear end cover; 6, second bearing; 7, third bearing; 8, front end cover; 9, first positioning shoulder hole; 10, second positioning shoulder hole; 11, axial positioning step. DETAILED DESCRIPTION

[0021] The utility model is further described below in conjunction with the accompanying drawings and implementation modes.

[0022] Please refer to Figure 1-Figure 4 ,in, Figure 1 A schematic diagram of a front cross-sectional structure of a preferred embodiment of a spindle box hole system structure capable of axially positioning a bearing provided by the utility model; Figure 2 It is the assembly drawing of the main shaft and the axle box in the utility model; Figure 3 It is a schematic diagram of the cross-sectional structure of a traditional axle box; Figure 4 This is the assembly drawing of the traditional spindle body and axle box.

[0023] The spindle box hole system structure capable of axially positioning the bearing comprises: an axle box 1, on which an assembly hole system is opened, in which a spindle body 2 is arranged; a pulley 3 for transmission, which is arranged on one end of the spindle body 2; a first bearing 4, a second bearing 6 and a third bearing 7 for supporting the rotation of the spindle body 2, wherein the first bearing 4, the second bearing 6 and the third bearing 7 are all fixedly sleeved on the spindle body 2; a rear end cover 5 and a front end cover 8 for covering the assembly hole system, wherein the rear end cover 5 and the front end cover 8 are respectively arranged at the two ends of the assembly hole system.

[0024] The assembly hole system is provided with positioning grooves matched with the first bearing 4, the second bearing 6 and the third bearing 7.

[0025] The rear end cover 5 and the front end cover 8 are both provided with through openings, and the through openings are adapted to fit the main shaft body 2 .

[0026] The rear end cover 5 and the front end cover 8 are both provided with a plurality of mounting holes, and locking screws for limiting the rear end cover 5 and the front end cover 8 are arranged in the mounting holes, and the plurality of locking screws are all threadedly connected to the axle box 1 .

[0027] A sealing ring is arranged in the through opening, and the sealing ring is an annular ring made of elastic material.

[0028] The pulley 3 is provided with a pin for limiting position, and the main shaft body 2 is provided with a groove matched with the pin.

[0029] A sensor for detecting the rotation state of the spindle body 2 is arranged in the assembly hole system.

[0030] It is worth mentioning that: Figure 3 The structure shown is a common design method for CNC lathe spindle units. The spindle body 1 is assembled into the spindle hole system of the axle box 1 through three sets of bearing supports (hole system simplified as Figure 1 ); The spindle body 1 rotates under the drive of the pulley. According to the provisions of the national standard, when the spindle inner cone is loaded with the spindle inspection mandrel of the standard inspection fixture, the circumferential runout of the mandrel near the spindle end is not more than 0.008mm, and the circumferential runout of the far end (300mm) is not more than 0.012mm. In addition, the stable temperature rise of the spindle does not exceed 20° from room temperature, and the stable temperature shall not be greater than 60°; In order to meet this mandatory standard, in addition to the high precision of the spindle, the precision of the bearing supporting the spindle and the installation precision of the bearing are also crucial. Since the bearing is a standard part, its precision also has national mandatory standards, so its installation precision, that is, the spindle hole system on the spindle box body for installing the bearing must also ensure sufficiently high precision; Figure 4 The spindle hole system shown has very high requirements for dimensional accuracy, form and position tolerances, and surface roughness. Appropriate hole system structure and appropriate processing technology and methods must be used to ensure processing quality requirements.

[0031] from Figure 3 Assembly drawings and Figure 4 It can be seen from the spindle hole system diagram of the spindle box that in this structure, the axial positioning of the bearing supporting the spindle is achieved by means of a hole shoulder. Due to the existence of the hole shoulder structure, the hole system processing method can only be achieved by horizontal installation, secondary clamping and boring, or using a turntable to turn the head and boring. According to mechanical common sense, secondary clamping or the rotation of the turntable will produce errors, and since the hole system is in a horizontal state (see Figure 4 ), the boring tool can only be processed in a horizontal manner, and the heavy tool will cause it to fall; therefore, in actual batch processing, the coaxiality accuracy of the spindle hole system is difficult to guarantee, and because the boring method is used for processing, the surface roughness of the hole is also difficult to meet the quality requirements, resulting in abnormal temperature rise of the spindle unit after assembly, short bearing life and excessive spindle assembly accuracy, which cannot meet the national standard requirements.

[0032] In order to solve the above problems, the structure of the spindle box is improved as follows: Figure 3 The bearing axial positioning hole shoulder 1 and hole shoulder 2 in the spindle hole system shown in the figure make the spindle hole system a through hole. The axial positioning of the bearing is achieved by machining a groove in the hole system and installing the front bearing axial positioning ring and the rear bearing axial positioning ring to achieve the necessary bearing axial positioning (for specific structure, see Figure 1 and Figure 2The purpose of the improvement is to change the processing method of the spindle hole system to vertical mill processing; during processing, the spindle hole system is in the vertical direction. Since the hole system is a through hole, the vertical mill spindle can be processed in full length up and down without secondary clamping or changing the processing direction. In addition, since the vertical mill spindle is also in the vertical direction, the deformation caused by its own weight can be prevented from affecting the processing accuracy; since this processing technology adopts the grinding process, the surface roughness of the spindle hole system can also be well guaranteed.

[0033] The above improvements have been put into practical use in the spindle unit of our company's TC-CT63100 slant bed CNC lathe, and achieved satisfactory results.

[0034] The working principle of the spindle box hole system structure for axial positioning of the bearing provided by the utility model is as follows:

[0035] This device eliminates the hole shoulder used for axial positioning of the bearing in the traditional design and designs the entire hole system as a through hole; during processing, the vertical grinding process is adopted, and the spindle hole system is in the vertical direction, avoiding deformation caused by the weight of the tool; the full-length up and down processing eliminates the errors caused by secondary clamping or turntable turning, and improves the processing accuracy and surface roughness of the spindle hole system; at the same time, by processing positioning grooves in the hole system and installing the front bearing axial positioning ring and the rear bearing axial positioning ring to achieve the necessary bearing axial positioning, the assembly process is simplified, and the installation accuracy of the bearing and the stability of the entire spindle unit are improved.

[0036] Compared with the related art, the spindle box hole system structure provided by the utility model for axial positioning of the bearing has the following beneficial effects:

[0037] The utility model provides a spindle box hole system structure capable of axially positioning the bearing. By eliminating the hole shoulder used for axial positioning of the bearing in the traditional design, the entire hole system is designed as a through hole. This design allows a more efficient vertical mill processing technology to be adopted, and various problems that may occur in horizontal processing are avoided. During vertical mill processing, the spindle hole system is in a vertical direction, which can avoid deformation caused by the deadweight of the tool, and the full-length up and down processing also eliminates the errors caused by secondary clamping or turntable turning. At the same time, by processing grooves in the hole system and installing the front bearing axial positioning ring and the rear bearing axial positioning ring, the necessary bearing axial positioning is achieved. This design simplifies the assembly process, improves the installation accuracy of the bearing and the stability of the entire spindle unit.

[0038] It should be noted that the equipment structure and drawings of the utility model mainly describe the principle of the utility model. In terms of the technology of the design principle, the settings of the power mechanism, power supply system and control system of the device are not fully described. However, on the premise that technical personnel in this field understand the principle of the above-mentioned utility model, they can clearly know the details of its power mechanism, power supply system and control system.

[0039] The above description is only an embodiment of the present invention, and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the contents of the specification and drawings of the present invention, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A spindle box hole system structure capable of axially positioning a bearing, characterized in that: include: An axle box, wherein the axle box is provided with an assembly hole system, and the main shaft body is arranged in the assembly hole system; A belt pulley for transmission, the belt pulley being arranged on one end of the main shaft body; A first bearing, a second bearing and a third bearing for supporting the main shaft body to rotate, wherein the first bearing, the second bearing and the third bearing are all fixedly sleeved on the main shaft body; A rear end cover and a front end cover are used to cover the assembly hole system, and the rear end cover and the front end cover are respectively arranged at two ends of the assembly hole system.

2. The spindle box hole system structure capable of axially positioning the bearing according to claim 1 is characterized in that: The assembly hole system is provided with positioning grooves matched with the first bearing, the second bearing and the third bearing.

3. The spindle box hole system structure capable of axially positioning the bearing according to claim 1 is characterized in that: The rear end cover and the front end cover are both provided with through openings, and the through openings are adapted to the main shaft body.

4. The spindle box hole system structure capable of axially positioning the bearing according to claim 1 is characterized in that: The rear end cover and the front end cover are both provided with a plurality of mounting holes, and locking screws for limiting the rear end cover and the front end cover are arranged in the mounting holes, and the plurality of locking screws are all threadedly connected with the axle box.

5. The spindle box hole system structure capable of axially positioning the bearing according to claim 3 is characterized in that: A sealing ring is arranged in the through opening, and the sealing ring is an annular ring made of elastic material.

6. The spindle box hole system structure capable of axially positioning the bearing according to claim 1 is characterized in that: The pulley is provided with a pin for limiting position, and the main shaft body is provided with a groove matched with the pin.

7. The spindle box hole system structure capable of axially positioning the bearing according to claim 1 is characterized in that: A sensor for detecting the rotation state of the main shaft body is arranged in the assembly hole system.

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