CN104625101B - Electro spindle is exported with the double end for eliminating axial influence of thermal deformation - Google Patents

Abstract

The invention discloses a double-head output electric spindle with the function of eliminating the influence of axial thermal deformation, which includes a main shaft assembly of a driving motor and a main shaft assembly of a driven motor. The active motor spindle assembly is composed of the active shaft, front and rear support bearings, built-in motor stator and rotor, etc.; the driven spindle assembly is composed of the driven shaft, bearing housing, support bearing, etc.; the active shaft and the driven shaft are equipped with output tool interfaces . The torque transmission connection structure that can slide freely in the axial direction is adopted between the driving shaft and the driven shaft, which can transmit the power of the built-in motor to the driven shaft, and allow the shaft to expand and contract axially when the shaft is thermally deformed to eliminate its influence. The electric spindle of the present invention can clamp two cutting tools at the left and right output ends for simultaneous processing, and can eliminate the influence of the axial position change of the output end and the increase in the load of the supporting bearing caused by the thermal axial deformation of the rotating shaft, and can improve The position accuracy of the output end of the electric spindle prolongs the working life of the supporting bearing.

Description

Double-headed output motorized spindle with the ability to eliminate the influence of axial thermal deformation

technical field

The invention relates to the technical field of mechanical processing and electric spindle, in particular to a double-head output electric spindle capable of eliminating the influence of axial thermal deformation.

Background technique

High-speed cutting can greatly improve cutting production efficiency, improve surface quality, shorten production cycle, and reduce production cost. High-speed electric spindle is a key component of high-speed cutting, and its function directly affects processing quality. Since the electric spindle is a precision component that rotates at high speed and adopts the form of a built-in motor, the heat dissipation of the electric spindle is not ideal, and the frictional heat generated by the high-speed bearing is also large. As the main heat source, the higher the rotational speed, the greater the frictional heat generation. Usually the electric spindle is assembled at normal temperature, and the spindle is heated and expanded in the working state. If it cannot be solved well, the machining accuracy will be reduced, and the pretightening force of the electric spindle bearing will increase, and the frictional heat will increase and the bearing will be burned.

At present, the usual electric spindle only has a single tool interface, and the machining of different structures usually needs to be stopped to change the tool, which affects the rapid processing speed. In addition, existing double-headed electric spindles, such as a double-headed electric spindle introduced by CN 203664686 and a high-speed double-headed engraving and milling electric spindle disclosed by CN 202317039, both adopt a structure in which one spindle is connected with two tools, and this structure can realize The electric spindle has the function of installing two tools, but the two output ends of the electric spindle are fixed installation. The heating of the electric spindle will cause the thermal expansion of the spindle, which will greatly reduce the position accuracy of the tool output end and cause additional heat inside the shaft. The stress and the additional load inside the support bearing increase, making the working condition of the main shaft and bearing worse.

Contents of the invention

The purpose of the present invention is to overcome the shortcomings of the above-mentioned prior art, and provide a double-head output electric spindle capable of eliminating the influence of axial thermal deformation. The machining accuracy, bearing preload change and other issues.

To achieve the above object, the present invention adopts the following technical solutions:

A double-head output electric spindle capable of eliminating the influence of axial thermal deformation, comprising a main motor shaft assembly and a driven shaft assembly, the active motor shaft assembly is composed of a driving shaft, a front bearing, a rear bearing, a built-in motor stator and a built-in motor rotor And the front bearing seat, housing, inner water jacket, front cover, front nut and rear nut, the driven shaft assembly is composed of the driven shaft, bearing seat, left support bearing, right support bearing, rear cover and lock nut; The left end of the driving shaft is provided with an output tool interface, and the right end of the driven shaft is provided with an output tool interface; the driving shaft and the driven shaft are connected by a torque transmission coupling structure that can slide freely in the axial direction.

The active rotating shaft of the active motor main shaft assembly is fixed with a built-in motor rotor and is supported by a front bearing and a rear bearing. The front bearing is installed in the front bearing seat and is compressed by a front nut, and the rear bearing is compressed on the active shaft by a rear nut. And installed in the bearing seat, the built-in motor stator is installed on the inner water jacket, the inner water jacket is placed in the electric spindle shell, and the right end of the driving shaft is provided with a torque transmission connection interface.

The driven shaft of the driven shaft assembly is supported in the bearing seat by a left support bearing and a right support bearing; the two support bearings are separated by an inner spacer and an outer spacer, and are pressed against the driven shaft by a lock nut. The left end of the driven shaft is provided with a torque transmission connection interface.

The torque transmission connection interface of the driving shaft cooperates with the torque transmission connection interface of the driven shaft to form a built-in torque transmission connection structure that can slide freely in the axial direction, and the two torque transmission connection interfaces of the torque transmission connection structure have a certain axial gap .

Compared with the prior art, the present invention has the following prominent substantive features and significant advantages:

1. The electric spindle of the present invention can hold two tools, and can process tools at both ends at the same time, saving processing time;

2. The electric spindle of the present invention has a structure that eliminates the influence of axial thermal deformation, which can eliminate the influence of thermal deformation on the additional thermal stress inside the rotating shaft and the additional load inside the support bearing, and at the same time eliminate the impact on the position accuracy of the left and right output ends of the electric spindle. Influence, prolong the working life of the electric spindle;

3. The structure of the electric spindle of the present invention that eliminates the influence of axial thermal deformation can be slightly deformed and applied to the traditional electric spindle with only one end output, and the structure has better versatility and practical value.

Description of drawings

Fig. 1 is a schematic cross-sectional view of the electric spindle of the present invention.

Fig. 2 is an enlarged schematic view of the torque transmission connection structure of the electric spindle of the present invention that can slide freely in the axial direction.

detailed description

Specific embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings.

As shown in Figure 1, a double-head output electric spindle with the ability to eliminate the influence of axial thermal deformation includes an active motor spindle assembly and a driven rotating shaft assembly. The active motor spindle assembly consists of an active rotating shaft 15, a front bearing 17, a rear bearing 10, Built-in motor stator 13, built-in motor rotor 14, front bearing housing 16, housing 11, inner water jacket 12, front cover 18, front nut 19, rear nut 10, driven shaft assembly consists of driven shaft 7, bearing housing 6 , left support bearing 8, right support bearing 3, back cover 2, lock nut 1 are formed.

The two ends of the electric spindle are respectively installed with a driving shaft 15 and a driven shaft 7, and the outer ends of the two shafts are provided with an output tool interface (in this embodiment, a BT handle interface). A rotor 14 is installed outside the driving shaft 15 of the electric spindle, and the rotor 14 is driven by the stator 13 , and the electrical interface of the spindle motor is arranged on the bearing seat 6 . The driving shaft 15 is supported inside the electric spindle through the front bearing 17 and the rear bearing 10 . Front bearing 17 is installed in front bearing seat 16, and front bearing seat 16 is connected by bolt with housing 11; Rear bearing 10 is installed in the bearing seat 6, and the mounting hole of the rear bearing 10 of bearing seat 6 is a smooth through hole.

As shown in Figure 2, when the active shaft 15 is heated and expanded, the rear bearing 10 can slide in the hole. The tail section of the active shaft 15 is provided with a torque transmission connection interface, and the tail section of the driven shaft 7 is provided with a torque transmission connection interface. The torque transmission connection interface of 15 cooperates with the torque transmission connection interface of the driven shaft 7 to form a built-in torque transmission connection structure 1501 that can slide freely in the axial direction. The positional accuracy changes of the two output terminals. In this embodiment, the axially freely slidable torque transmission coupling structure 1501 of the two main shafts is connected in the form of splines. In addition, the torque transmission coupling structure 1501 that can slide freely in the axial direction can be connected by splines, profile connections, sliding key connections and other structures. The two torque transmission coupling interfaces of the torque transmission coupling structure 1501 that can slide freely in the axial direction have a certain axial gap, so that collision and interference will not occur when the main shaft is heated and expanded.

Referring to Fig. 1, the driven rotating shaft 7 is supported in the bearing seat 7 by the left and right supporting bearings, and the middle of the two supporting bearings is separated by the inner spacer 5 and the outer spacer 4, so that the driven rotating shaft 7 can be better supported, and the two supporting bearings It is compressed on the driven shaft 7 by the lock nut 1 . In this embodiment, the support bearing and the front bearing 17 are sealed in a labyrinth airtight manner. The inner water jacket 12 is processed with a cooling spiral water channel, which corresponds to the water outlet and inlet drilled on the casing 11. The inner water jacket 12 and the casing 11 are interference fit, and a water cooling structure is added to the main heat source spindle motor. , can effectively reduce the temperature of the motor and reduce the thermal expansion of the spindle.

Claims (3)

1. A double-headed output electric spindle capable of eliminating the influence of axial thermal deformation, including the main shaft assembly of the active motor and the driven shaft assembly, characterized in that: the main shaft assembly of the active motor consists of an active shaft (15), a front bearing (17 ), rear bearing (10), built-in motor stator (13) and built-in motor rotor (14) and front bearing seat (16), housing (11), inner water jacket (12), front cover (18), front nut (19), rear nut (9), driven shaft assembly consists of driven shaft (7), bearing housing (6), left support bearing (8), right support bearing (3), rear cover (2), lock Composed of tight nuts (1); the left end of the driving shaft (15) is provided with an output tool interface, and the right end of the driven shaft (7) is provided with an output tool interface; the driving shaft (15) and the driven shaft ( 7) are connected by a torque transmission coupling structure (1501) that can slide freely in the axial direction; the torque transmission coupling interface of the driving shaft (15) cooperates with the torque transmission coupling interface of the driven shaft (7) to form a built-in type that can A torque transmission connection structure (1501) that slides freely in the axial direction, and the two torque transmission connection interfaces of the torque transmission connection structure (1501) have a certain axial clearance. 2. The double-head output electric spindle capable of eliminating the influence of axial thermal deformation according to claim 1, characterized in that: the active shaft (15) of the active motor spindle assembly is fixed with a built-in motor rotor (14) and is composed of The front bearing (17) and the rear bearing (10) are supported, the front bearing (17) is installed in the front bearing seat (16) and is compressed by the front nut (19), and the rear bearing (10) is compressed by the rear nut (9) On the driving shaft (15) and installed in the bearing seat (6), the built-in motor stator (13) is installed on the inner water jacket (12), and the inner water jacket (12) is installed in the electric spindle housing (11), The right end of the active rotating shaft (15) is provided with a torque transmission connection interface. 3. The double-headed output electric spindle capable of eliminating the influence of axial thermal deformation according to claim 1, characterized in that: the driven shaft (7) of the driven shaft assembly is supported by a left support bearing (8) and a right The bearing (3) is supported in the bearing seat (6); the two supporting bearings are separated by the inner spacer (5) and the outer spacer (4), and are pressed tightly on the driven shaft (7) by the lock nut (1) , the left end of the driven shaft (7) is provided with a torque transmission connection interface.