阅读说明：本技术 机床进给系统和数控机床 (Machine tool feeding system and numerical control machine tool ) 是由 张红梅 郭航 崔中 贾存齐 薛乃凤 于 2021-08-13 设计创作，主要内容包括：本发明提出了机床进给系统和数控机床,包括可切换的宏位移驱动机构和微位移驱动机构,其中宏位移驱动机构采用伺服电机配合传动丝杠的方式驱动数控机床的工作台,微位移驱动机构采用直线电机驱动工作台；本发明兼具宏位移驱动机构和微位移驱动机构,一次夹装定位即可对工件连续进行粗加工和精加工,并在加工精度、加工效率和能耗之间取得更好的平衡效果。宏位移驱动机构和微位移驱动机构通过锁紧机构快速连接和分离,实现了宏位移进给和和微位移进给的快速切换；宏位移驱动机构和微位移驱动机构各自具有独立的位移测量机构,从而满足大范围、高速、高精密的定位要求。(The invention provides a machine tool feeding system and a numerical control machine tool, which comprise a switchable macro-displacement driving mechanism and a micro-displacement driving mechanism, wherein the macro-displacement driving mechanism drives a workbench of the numerical control machine tool in a mode that a servo motor is matched with a transmission lead screw, and the micro-displacement driving mechanism drives the workbench by a linear motor; the invention has the advantages of both macro-displacement driving mechanism and micro-displacement driving mechanism, can continuously carry out rough machining and finish machining on the workpiece by clamping and positioning once, and obtains better balance effect among machining precision, machining efficiency and energy consumption. The macro displacement driving mechanism and the micro displacement driving mechanism are quickly connected and separated through the locking mechanism, so that the quick switching between macro displacement feeding and micro displacement feeding is realized; the macro displacement driving mechanism and the micro displacement driving mechanism are respectively provided with an independent displacement measuring mechanism, so that the positioning requirements of large range, high speed and high precision are met.)

1. The machine tool feeding system comprises a switchable macro-displacement driving mechanism and a switchable micro-displacement driving mechanism, and is characterized in that the macro-displacement driving mechanism drives a workbench of a numerical control machine tool in a mode that a servo motor is matched with a transmission lead screw, and the micro-displacement driving mechanism drives the workbench by adopting a linear motor.

2. The machine tool feed system of claim 1, wherein the macro displacement drive mechanism is coupled to the micro displacement drive mechanism;

the working table is connected with the macro displacement driving mechanism, or

The workbench is connected with the micro-displacement driving mechanism.

3. The machine tool feeding system of claim 2, wherein the worktable is connected with the micro-displacement driving mechanism, and the macro-displacement driving mechanism is locked or separated with the micro-displacement driving mechanism through a locking mechanism;

in a rough machining state, the micro-displacement driving mechanism does not work, and the macro-displacement driving mechanism is connected with the micro-displacement driving mechanism through a locking mechanism and drives the workbench to move;

and when in a finish machining state, the micro-displacement driving mechanism is separated from the macro-displacement driving mechanism, and the workbench is driven to move independently.

4. The machine tool feed system of claim 3, wherein the locking mechanism comprises a lock hole and a locking shaft inserted into the lock hole;

one of the lock hole and the locking shaft is positioned on the macro displacement driving mechanism, and the other one of the lock hole and the locking shaft is positioned on the micro displacement driving mechanism.

5. The machine tool feeding system of claim 4, wherein the locking hole is wedge-shaped, and the head of the locking shaft is provided with a wedge-shaped block which is matched with the locking hole.

6. The machine tool feed system of claim 4, wherein the locking mechanism comprises a cylinder and a spring;

the cylinder is connected with the tail part of the locking shaft and used for driving the locking shaft to stretch;

the spring is used for accelerating the retraction of the locking shaft.

7. The machine tool feed system of claim 1 wherein the macro and micro displacement drives each have independent displacement measurement mechanisms.

8. The machine tool feeding system of claim 7, wherein the worktable moves along a guide rail along with the macro displacement driving mechanism and the micro displacement driving mechanism, a first grating ruler is arranged parallel to the guide rail, the macro displacement driving mechanism is provided with a first reading head, the micro displacement driving mechanism is provided with a second reading head, and the second reading head and the first reading head share the first grating ruler; or

And a second grating ruler is arranged in parallel to the guide rail, and the second reading head reads through the second grating ruler.

9. The machine tool feed system of claim 1, wherein the screw is a ball screw.

10. Numerical control machine tool comprising a machine tool feeding system according to any one of the preceding claims.

Technical Field

The invention relates to the technical field of numerical control machines, in particular to a machine tool feeding system and a numerical control machine tool.

Background

The machining process of a common workpiece is divided into rough machining and finish machining, and the rough machining and the finish machining are usually completed in a plurality of stations. A feeding system with high positioning precision and high speed is needed for high-precision workpieces such as dies, non-circular sections and the like, and higher requirements are put forward for a positioning feeding system of high-precision machine tool machining equipment.

In the rough machining process, the cutting amount and the feeding amount are large, the transmission speed of the traditional mode of 'a motor + a coupler + a lead screw' is stable, the bearing capacity of the system is higher than that of other driving modes, and the requirements of large machining amount and stroke amount are met. However, when the workpiece is processed in a fine machining or ultra-precision machining mode, the size of most of the workpiece to be processed is only required to be a few microns, and the motion mechanism continuously reciprocates in the machining process to meet the machining requirements. Therefore, when a workpiece is subjected to precise or ultra-precise machining, a servo mechanism always needs to operate in a certain tiny-sized stroke, and long-time machining is needed, so that obvious local abrasion is caused to a transmission system of a ball screw, and the precision of the servo system is seriously influenced.

How to finish the processing of the workpiece under the working conditions of high speed, high positioning precision and low energy consumption becomes a technical difficulty of the industry, and the processing precision of two major factors of stroke and precision under the traditional single driving mode can not meet the requirement of the workpiece precision.

Disclosure of Invention

In view of the above, the present invention provides a feeding system for a machine tool and a numerical control machine tool, which are provided with a macro-displacement driving mechanism driven by a servo motor and a micro-displacement driving mechanism driven by a linear motor, and can continuously perform rough machining and finish machining on a workpiece by one-time workpiece clamping and positioning, and achieve better balance among machining precision, machining efficiency and energy consumption.

The invention provides a machine tool feeding system which comprises a macro-displacement driving mechanism and a micro-displacement driving mechanism which can be switched, wherein the macro-displacement driving mechanism drives a workbench of a numerical control machine tool in a mode that a servo motor is matched with a transmission lead screw, and the micro-displacement driving mechanism drives the workbench by a linear motor.

Preferably, the macro displacement driving mechanism is connected with the micro displacement driving mechanism;

the working table is connected with a macro-displacement driving mechanism, or

The workbench is connected with the micro-displacement driving mechanism.

Preferably, the workbench is connected with the micro-displacement driving mechanism, and the macro-displacement driving mechanism is locked or separated from the micro-displacement driving mechanism through a locking mechanism;

in a rough machining state, the micro-displacement driving mechanism does not work, and the macro-displacement driving mechanism is connected with the micro-displacement driving mechanism through the locking mechanism and drives the workbench to move;

and when in a finish machining state, the micro-displacement driving mechanism is separated from the macro-displacement driving mechanism, and the workbench is independently driven to move.

Preferably, the locking mechanism comprises a lock hole and a locking shaft inserted into the lock hole;

one of the lock hole and the locking shaft is positioned on the macro displacement driving mechanism, and the other one is positioned on the micro displacement driving mechanism.

Preferably, the shape of the lock hole is wedge-shaped, and a wedge-shaped block matched with the lock hole is arranged at the head of the locking shaft.

Preferably, the locking mechanism comprises a cylinder and a spring;

the cylinder is connected with the tail part of the locking shaft and used for driving the locking shaft to stretch;

the spring is used for accelerating the retraction of the locking shaft.

Preferably, the macro displacement drive mechanism and the micro displacement drive mechanism each have an independent displacement measurement mechanism.

Preferably, the workbench moves along the guide rail along with the macro-displacement driving mechanism and the micro-displacement driving mechanism, a first grating ruler is arranged in parallel with the guide rail, the macro-displacement driving mechanism is provided with a first reading head, the micro-displacement driving mechanism is provided with a second reading head, and the second reading head and the first reading head share the first grating ruler; or

And a second grating ruler is arranged in parallel with the guide rail, and the second reading head reads through the second grating ruler.

Preferably, the screw is a ball screw.

The invention also provides a numerical control machine tool comprising the machine tool feeding system provided by any technical scheme.

The invention has the beneficial effects that: the device is provided with a macro displacement driving mechanism and a micro displacement driving mechanism, and can continuously perform rough machining and finish machining on a workpiece by clamping and positioning once; the macro displacement driving mechanism and the micro displacement driving mechanism are quickly connected and separated through the locking mechanism, so that the quick switching between macro displacement feeding and micro displacement feeding is realized; the macro displacement driving mechanism and the micro displacement driving mechanism are respectively provided with an independent displacement measuring mechanism, so that the positioning requirements of large range, high speed and high precision are met.

Drawings

The invention is described in detail below with reference to examples and figures, in which:

fig. 1 is a diagrammatic view of the cross-section of a machine tool feed system in the direction of motion.

Fig. 2 is a cross-sectional view along the direction of movement of the locking mechanism in the locked state.

Fig. 3 is a sectional view along the direction of movement of the locking mechanism in the disengaged state.

Fig. 4 is a side cross-sectional view of the locking mechanism in the locked condition.

Fig. 5 is a force diagram of the locking mechanism.

Fig. 6 is a flow chart of the operation of the machine tool feed system.

Description of reference numerals:

1-a workbench, 2-a guide rail, 3-a rotor, 4-a stator, 5-an adapter plate, 6-a ball screw, 7-a locking plate, 81 locking holes, 82-a locking shaft, 83-an adapter shaft, 84-a cylinder, 85-a spring, 91-a first grating ruler, 92-a first reading head, 93-a second grating ruler and 94-a second reading head.

Detailed Description

In order to make the technical problems, technical solutions and advantageous effects to be solved by the present invention more clearly apparent, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Thus, a feature indicated in this specification will serve to explain one of the features of one embodiment of the invention, and does not imply that every embodiment of the invention must have the stated feature. Further, it should be noted that this specification describes many features. Although some features may be combined to show a possible system design, these features may also be used in other combinations not explicitly described. Thus, the combinations illustrated are not intended to be limiting unless otherwise specified.

The principles of the present invention will be described in detail below with reference to the accompanying drawings and embodiments.

The invention provides a machine tool feeding system which is simultaneously provided with a macro-displacement driving mechanism driven by a servo motor and a micro-displacement driving mechanism driven by a linear motor, and can carry out rough machining and finish machining on a workpiece through one-time workpiece clamping and positioning.

In the embodiment, the workpiece is fixed on the workbench 1, and the machine tool feeding system drives and controls the displacement of the workbench 1 so as to control the processing of the workpiece.

The machine tool feeding system comprises a switchable macro-displacement driving mechanism and a switchable micro-displacement driving mechanism; the macro-displacement driving mechanism is used for rough machining of a workpiece, namely machining of a larger size and a larger outline, and a servo motor is matched with a transmission lead screw to drive the workbench 1; the micro-displacement driving mechanism is used for workpiece finish machining, namely micro-size and contour machining, and a linear motor is adopted to drive the workbench 1.

The screw may be a sliding screw or a ball screw. Since the number of servo motor transmission chains is large, it is difficult to realize rapid progression, and therefore the ball screw is adopted in the embodiment.

When fine machining is carried out, the workbench 1 runs in a certain stroke with a tiny size, if a servo motor is used for a long time to be matched with a transmission lead screw for driving, obvious local abrasion can be caused to a transmission system of a ball lead screw, the precision of the servo system is influenced, and the problem of abrasion of the transmission system can be solved by adopting linear motor driving; in addition, the linear motor has greater advantages in speed, and the speed of the linear motor is 300 m/min; acceleration is 10g and speed of the ball screw is 120 m/min; the acceleration is 1.5g, so the linear motor drive can be adopted to ensure that the machine tool obtains higher processing efficiency.

However, when the same torque is provided, the energy consumed by the linear motor is about more than twice that consumed by the rotary servo motor and the ball screw. Therefore, a servo motor is adopted to be matched with a ball screw to drive during rough machining, and a linear motor is adopted to drive during finish machining, so that better balance between energy consumption and machining efficiency can be obtained.

In order to realize direct finish machining after rough machining on the same station, in the embodiment, the micro-displacement driving mechanism is fixedly connected with the workbench 1, and the macro-displacement driving mechanism is connected with the micro-displacement driving mechanism through the locking mechanism; when in rough machining, the linear motor does not work, and the servo motor drives the workbench to work through the ball screw; when the fine machining is carried out, the macro displacement driving mechanism is separated through the locking mechanism, mechanical abrasion caused by passive reverse operation is avoided, and when the linear motor does not work, the linear motor is only equivalent to a common sliding mechanism, and the reverse operation abrasion can be avoided.

Fig. 1 is a longitudinal sectional view showing a specific structure of the present embodiment, and as shown in the drawing, a machine tool feeding system is installed in a chute and slides along parallel guide rails 2 arranged on both sides of the chute;

the micro-displacement driving mechanism comprises a rotor 3, a stator 4 and an adapter plate 5, wherein the rotor 3 is fixed at the bottom of the workbench 1, the stator 4 is arranged at two sides of the sliding groove, and the adapter plate 5 is fixedly connected with the rotor 3;

the macro displacement driving mechanism comprises a servo motor (not shown in the figure), a ball screw 6 and a locking plate 7, the ball screw 6 is fixedly arranged at the bottom of the locking plate 7 and drives the workbench 1 to move axially, and the locking plate 7 is connected with or separated from the adapter plate 5 through the locking mechanism.

FIGS. 2-4 illustrate specific embodiments of the locking mechanism;

in this embodiment, the locking mechanism includes a locking hole and a locking shaft 82 inserted into the locking hole 81, wherein the locking hole 81 is disposed at the bottom of the adapter plate 5, and the locking shaft 82 is installed in the pre-opening hole of the locking plate 7;

the locking mechanism further comprises a transfer shaft 83, an air cylinder 84 and a spring 85, the locking shaft 82 and the air cylinder 84 are connected together through the transfer shaft 83, the system controls the locking shaft 82 to enter a locking hole through the air cylinder 84 to lock the locking plate 7 and the transfer plate 5, or retracts the locking plate 7 to separate the locking plate 7 and the transfer plate 5;

the spring 85 is installed on the periphery of the transfer shaft 83 or the locking shaft 82, and when the locking plate 7 in the locking state needs to be separated from the transfer plate 5, the spring 85 is used for providing elastic force for retracting the transfer shaft 83 and accelerating the retraction of the transfer shaft 83, so that the time for switching from rough machining to fine machining is shortened, and the machining efficiency of the machine tool is improved.

In the embodiment, the lock hole is wedge-shaped, and the head of the locking shaft is provided with a wedge-shaped block matched with the lock hole;

FIG. 2 shows the specific shape of the wedge from the direction of movement of the feed system of the machine tool, FIG. 4 from the side, and FIG. 5 shows the parameters and force diagram of the wedge;

single side clamping force of wedge block in fig. 4Andcomprises the following steps:

compared with clamping mechanisms with other shapes, the wedge-shaped force increasing mechanism has the functions of changing the direction of the clamping action and increasing the force; in addition, the wedge-shaped block has small clamping stroke: although the stroke of the up-and-down movement is not changed, the required cylinder stroke for achieving the same effect is small, for example, the stroke of a square block is s, and the stroke of a wedge block is s si na 15.5.

In this embodiment, the macro displacement driving mechanism and the micro displacement driving mechanism are respectively provided with independent displacement measuring mechanisms;

the macro displacement driving mechanism is provided with a first grating ruler 91 and a first reading head 92, the first grating ruler 91 is arranged on the side wall of one side of the sliding chute in parallel with the guide rail 2, and the first reading head 92 is arranged on the locking plate 7 and is opposite to the first grating ruler 91;

the micro-displacement driving mechanism is provided with a second grating scale 93 and a second reading head 94, the second grating scale 93 is parallel to the guide rail 2 and is fixedly arranged below the adapter plate 5, and the second reading head 94 is arranged on the adapter plate 5 and is opposite to the second grating scale 93.

As shown in fig. 6, when in the rough machining state, the micro-displacement driving mechanism does not work, the macro-displacement driving mechanism controls the servo motor to drive the worktable 1 to move through the ball screw 6 by the computer, and the displacement signal measured by the first reading head 92 is continuously fed back to the control system, so that the control of the servo motor forms a closed-loop system;

when the rough machining action is finished, the workpiece enters a fine machining state, the control interface sends a signal to enable the servo motor to stop working, a piston of a cylinder 84 in the locking mechanism is in a retraction state, the adapter plate 5 is separated from the locking plate 7, and the micro-driving is informed to start working; the movement of the working table 1 is driven by the electromagnetic acting force of the rotor 3 and the stator 4, and the displacement signal measured by the second reading head 94 is continuously fed back to the control system, so that the control of the linear motor also forms a closed-loop system; for example, when the length of a workpiece to be machined is 5.02mm, the rough machining dimension is set to be 5mm, and the finish machining dimension is set to be 0.02mm, the machine tool feeding system is switched from the servo motor drive to the linear motor drive when the workpiece is machined to be 5mm, and the conversion from rough machining to finish machining is realized.

The invention also provides a numerical control machine tool which is provided with the machine tool feeding system described in any embodiment.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.