CN116394070A - Intelligent knife handle and system for measuring cutting force and cutting vibration in real time - Google Patents

Abstract

The invention discloses an intelligent knife handle and a system for measuring cutting force and cutting vibration in real time, and relates to the technical field of signal monitoring, wherein the intelligent knife handle comprises a knife handle main body, a circuit carrier for installing a data acquisition system is sleeved outside the knife handle main body, and a shell is arranged outside the circuit carrier; a plurality of detection beam structures are circumferentially distributed on the cutter handle main body, and piezoelectric film force sensors are fixed on the surfaces of the detection beam structures; and a plurality of vibration sensors are arranged on the side face of the circuit carrier, and the vibration sensors and the piezoelectric film force sensor are both connected with a data acquisition system. The invention takes a piezoelectric film sensor as a sensitive element, and acquires a force signal aiming at a designed elastic strain structure, and acquires a vibration signal by utilizing a vibration sensor; the acquisition and transmission are integrated, so that the three-dimensional cutting force signal and the two-way vibration signal in the cutting process can be monitored.

Description

Intelligent knife handle and system for measuring cutting force and cutting vibration in real time

Technical Field

The invention relates to the technical field of signal monitoring, in particular to an intelligent knife handle and system for measuring cutting force and cutting vibration in real time.

Background

In the field of cutting machining, high-precision machining has high requirements on real-time performance of a monitoring system. As a processing terminal in the cutting field, intelligent monitoring of the state of a cutter has great significance in improving the processing efficiency and the processing quality. The conventional sensors are generally distributed around the workbench, and the monitoring mode is difficult to apply to a production line due to the large number of devices, complex operation and large structure and size, which restricts the development of a monitoring system. The intelligent measuring knife handle integrated with the traditional sensor not only can solve the problems of more, mess and impurity of traditional wiring harnesses, but also has the characteristic of simplicity in operation.

In the prior art, the intelligent force measuring knife handle of the vibration measuring knife handle mostly adopts a strain resistor or a rigid piezoelectric crystal as a sensitive original. The strain type knife handle detects a force signal according to a metal strain effect, has a narrow measuring range and low linearity, and is not suitable for measuring high dynamic force. Piezoelectric knife handle has a mature commercial scheme for measuring force signals according to material piezoelectric effect, but piezoelectric wafers are expensive, so that the influence on the structure of the knife handle is large, and maintenance is difficult.

The thin film polyvinylidene fluoride piezoelectric sensor (PVDF piezoelectric thin film for short) is a promising technology in the aspect of surface strain, has the characteristics of wide frequency band, high sensitivity and high dynamic range of piezoelectric materials, and is low in cost and convenient to install. In the prior art, as disclosed in patent (CN 108481088A), a wireless force measuring system for milling and a method thereof, the method uses a piezoelectric film as a sensing element, but the method is not aimed at designing a cutter handle structure, and a measuring structure is easy to generate larger deviation.

Disclosure of Invention

Aiming at the defects existing in the prior art, the invention aims to provide an intelligent knife handle and a system for measuring cutting force and cutting vibration in real time, wherein a piezoelectric film sensor is used as a sensitive element, a force signal is acquired aiming at a designed elastic strain structure, and a vibration signal is acquired by using a vibration sensor; the acquisition and transmission are integrated, so that the three-dimensional cutting force signal and the two-way vibration signal in the cutting process can be monitored.

In order to achieve the above object, the present invention is realized by the following technical scheme:

in a first aspect, an embodiment of the present invention provides an intelligent shank for measuring cutting force and cutting vibration in real time, including a shank main body, wherein a circuit carrier for mounting a data acquisition system is sleeved outside the shank main body, and a housing is mounted outside the circuit carrier; a plurality of detection beam structures are circumferentially distributed on the cutter handle main body, and piezoelectric film force sensors are fixed on the surfaces of the detection beam structures; and a plurality of vibration sensors are arranged on the side face of the circuit carrier, and the vibration sensors and the piezoelectric film force sensor are both connected with a data acquisition system.

As a further implementation manner, the circuit carrier body is cylindrical, and a plurality of installation spaces are formed in the circumferential direction of the circuit carrier body so as to form an installation cavity of the data acquisition system with the shell.

As a further implementation manner, a plurality of grooves are formed in the side face of the bottom of the circuit carrier, and the vibration sensor is fixed in the grooves.

As a further implementation mode, the circumference of the cutter handle main body is also provided with a support beam structure, the cross section of the detection beam structure is of a cross-shaped structure, and gaps are formed between adjacent beams, so that the gaps are distributed in a groined structure.

As a further implementation manner, the data acquisition system comprises a signal amplifying circuit, an analog-to-digital conversion circuit, a signal conditioning circuit and a wireless transmission circuit which are sequentially connected, wherein the wireless transmission circuit is used for communicating with an upper computer;

the circuits are all connected with a power supply circuit, and the piezoelectric film force sensor and the vibration sensor are connected with a signal amplifying circuit.

As a further implementation manner, a power switch, a charging socket, a signal indicator lamp and a power indicator lamp which are connected with a power supply circuit are installed on the top of the shell.

As a further implementation manner, the signal indicator light is connected with the wireless transmission circuit so as to be lightened when the wireless transmission circuit establishes connection with the upper computer.

As a further implementation manner, the shell is composed of a side plate and a top plate and a bottom plate which are connected with the side plate.

As a further implementation, the shank body end is connected to a collet that connects to a cutter or cap.

In a second aspect, an embodiment of the present invention further provides a system for measuring cutting force and cutting vibration in real time, including a machine tool and the intelligent tool shank, where the intelligent tool shank is mounted on a spindle of the machine tool.

The beneficial effects of the invention are as follows:

(1) The circuit carrier for installing the data acquisition system is sleeved outside the cutter handle main body, a plurality of detection beam structures are circumferentially distributed on the cutter handle main body, the surface of each detection beam structure is fixedly provided with a piezoelectric film force sensor, and a plurality of vibration sensors are installed on the side face of the circuit carrier, so that a three-dimensional cutting force signal and a two-way vibration signal in the cutting process can be monitored.

(2) The invention is provided with a data acquisition system, strain is generated through a piezoelectric film force sensor, charges are generated between electrodes and are transmitted to an information acquisition system, and the charges are converted into voltage signals and output to an upper computer; the vibration sensor monitors cutting vibration generated on the cutter-handle-main shaft system, and converts a vibration signal into an electric signal and transmits the electric signal to the upper computer, so that the cutting force signal and the vibration signal are monitored.

(3) The tool handle main body, the circuit carrier, the shell and the like adopt detachable structures, can be matched with machine tool spindles of different types, and have the characteristics of wide application range, convenience in operation and low cost.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention.

FIG. 1 is a schematic view of a shank structure according to one or more embodiments of the invention;

FIG. 2 is an exploded view of a tool shank according to one or more embodiments of the invention;

FIG. 3 is a cross-sectional view of a tool shank according to one or more embodiments of the invention;

FIG. 4 is a schematic view of a shank body structure according to one or more embodiments of the invention;

FIG. 5 is a cross-sectional view of a shank body A-A according to one or more embodiments of the invention;

FIG. 6 is a schematic diagram of a circuit carrier structure in accordance with one or more embodiments of the invention;

fig. 7 is a schematic diagram of an information acquisition system according to one or more embodiments of the invention.

The tool handle comprises a tool handle body, a 1a, a detection beam structure, a 1b, a support beam structure, a 2, a power switch, a 3, a charging socket, a 4, a signal indicator, a 5, a power indicator, a 6, a top plate, a 7, a piezoelectric film force sensor, an 8, a circuit carrier, a 9, a vibration sensor, a 10, a counterweight, a 11, a first fixing screw, a 12, a bottom plate, a 13, a second fixing screw, a 14, a side plate, a 15, a third fixing screw, a 16, a collet chuck, a 17, a cap, a 18, a power supply circuit, a 19, a signal amplifying circuit, a 20, an analog-to-digital conversion circuit, a 21, a signal conditioning circuit, a 22, a wireless transmission circuit, a 23, a groove, a 24 and a threaded hole.

Detailed Description

Embodiment one:

the embodiment provides an intelligent knife handle for measuring cutting force and cutting vibration in real time, which is shown in fig. 1-3, and comprises a knife handle main body 1, a shell, a piezoelectric film force sensor 7, a circuit carrier 8, a vibration sensor 9, a data acquisition system and the like, wherein the circuit carrier 8 is sleeved outside the knife handle main body 1 and is arranged in the shell; when in use, the tool shank main body 1 is arranged on a main shaft of a machine tool through an HSK standard tool shank connector.

As shown in fig. 2 and 3, the end of the shank body 1 is provided with a collet 16, and the collet 16 is used for clamping a cutter; when the cutter is not mounted, a cap 17 is mounted on the outside of the collet 16.

The shell is used for protecting internal signals from being interfered by the outside and playing a role in preventing water and corrosion; the shell of the embodiment is of a detachable structure and comprises a top plate 6, a bottom plate 12 and a side plate 14, wherein the top plate 6 is arranged at the top of the side plate 14 by taking the installation state of the tool shank as a reference, the bottom plate 12 is arranged at the bottom of the side plate 14, and the three parts form a hollow columnar structure; and the top plate 6 and the bottom plate 12 are correspondingly provided with holes for the tool shank main body 1 to pass through, and the bottom plate 12 is in threaded connection with the tool shank main body 1.

As shown in fig. 1 and 2, the top plate 6 is provided with a plurality of through holes for installing the power switch 2, the charging jack 3, the signal indicator lamp 4 and the power indicator lamp 5.

The handle body 1 and the bottom plate 12, the circuit carrier 8 and the bottom plate 12, and the circuit carrier 8 and the side plate 14 are all fixed by screws, and for convenience of description, the embodiment adopts "first", "second" and "third", that is, the handle body 1 and the bottom plate 12 are connected by a plurality of first fixing screws 11, the circuit carrier 8 and the bottom plate 12 are connected by a plurality of second fixing screws 13, and the circuit carrier 8 and the side plate 14 are connected by a plurality of third fixing screws 15.

The piezoelectric film force sensor 7 is installed on the outer side of the cutter handle main body 1, as shown in fig. 4 and 5, a plurality of detection beam structures 1a and a plurality of support beam structures 1b are uniformly processed in the circumferential direction of the middle part of the cylindrical cutter handle, gaps which are uniformly distributed exist between adjacent beams, and the piezoelectric film force sensor 7 is attached to the side wall of the detection beam structure 1 a.

In the embodiment, the detection beam structure 1a and the support beam structure 1b are respectively provided with four, the cross sections of the detection beam structure 1a are distributed in a cross shape, and the cross-shaped detection beam structure enables the piezoelectric film to face the X, Y direction, so that the decoupling of force is facilitated, and the sensitivity is ensured; and the support beam structure ensures that the shank has sufficient rigidity.

The outer surface of the detection beam structure 1a is processed into a plane so as to fix the piezoelectric film force sensor 7 for measuring X-direction force, Y-direction force and torsion around the Z axis; as shown in fig. 5, gaps between the four detection beam structures 1a and the four support beam structures 1b are distributed in a zigzag structure; the evenly distributed detection beams and gaps can ensure the dynamic balance of the rotor system of the cutter handle.

As shown in fig. 6, four holes are formed at the top of the circuit carrier 8 corresponding to the top plate 6 to mount the power switch 2, the charging socket 3, the signal indicator lamp 4 and the power indicator lamp 5, and the power switch 2, the charging socket 3, the signal indicator lamp 4 and the power indicator lamp 5 are connected with the internal circuit of the circuit carrier 8. An information acquisition system is arranged in the circuit carrier 8 to realize the conversion of strain signals, charge signals and voltage signals and carry out wireless transmission; the circuit carrier 8 is fixed on the handle body through the bottom plate 12 to ensure the normal operation of the circuit.

In the processing process, the tool handle main body 1 is connected with the main shaft, the tool handle and the tool system rotate to cut, the tool blade is transmitted to the tool handle by the reaction force to induce the tool handle to generate strain, meanwhile, the piezoelectric film force sensor 7 generates strain, charges are generated between electrodes, the charges are transmitted to the information acquisition system, and the charges are converted into voltage signals and output to the upper computer.

Further, the main body of the circuit carrier 8 is in a cylindrical structure, four installation spaces are circumferentially formed in the middle of the main body, and an installation cavity is formed between the main body and the side plate 14 and is used for an information acquisition system, the counterweight 10 and the like. The circuit carrier 8 is provided with a plurality of grooves 23 along the outer circumference, threaded holes 24 are formed at the side of each groove 23, the vibration sensor 9 and the circuit board are fixed in the grooves 23 by bolts and used for measuring vibration signals, a certain gap is reserved between the grooves and the side plates 14 and used for arranging the lines of the vibration sensors 9, and the vibration signals in the X direction and the Y direction are measured by the two vibration sensors 9.

In this embodiment, each vibration sensor 9 is a PCB board, and includes an ADXL1001 vibration sensor chip and a low-pass filter circuit of ideno semiconductor company, which are respectively disposed in the direction X, Y. For balance, a blank PCB board is mounted on the opposite side as the weight 10. The structure is close to a processing area, and signal acquisition is more accurate; the influence on the main structure of the cutter handle is low, and the cutter handle is easy to install and maintain.

During processing, cutter vibration signals are transmitted to the cutter handle main body 1 and drive the circuit carrier 8 to vibrate, the vibration signals in the X, Y direction are monitored and collected by the two vibration sensors 9, and the vibration signals are transmitted to the information collecting system through a circuit.

As shown in fig. 7, the information acquisition system includes a power supply circuit 18, a signal amplification circuit 19, an analog-to-digital conversion circuit 20, a signal conditioning circuit 21, and a wireless transmission circuit 22, where the piezoelectric film force sensor 7 and the vibration sensor 9 are respectively connected to the signal amplification circuit 19, the analog-to-digital conversion circuit 20, and the signal conditioning circuit 21 are sequentially connected, and the signal conditioning circuit 21 is connected to an upper computer through the wireless transmission circuit 22. The circuits are all connected with a power supply circuit 18, and the power switch 2, the charging jack 3, the signal indicator lamp 4 and the power indicator lamp 5 are connected with the power supply circuit 18.

Before processing monitoring begins, the power supply circuit 18 is controlled to supply power to other modules through the power switch 2, the power indicator lamp 5 is turned on when power is supplied successfully, the measuring knife handle is charged through the charging socket 3 when power is insufficient, the wireless transmission circuit 22 is started after power is supplied, WIFI is searched according to a preset IP address and port number, an upper computer program is started, the WIFI service is activated, the wireless transmission circuit 22 is connected with the upper computer, the signal indicator lamp 4 is turned on, and preparation work is finished.

In the processing monitoring process, the vibration sensor 9 monitors cutting vibration generated on the cutter-handle-main shaft system, converts vibration signals into electric signals, the electric signals are amplified by the signal amplifying circuit 19, converted into digital signals by the analog-to-digital conversion circuit 20, then subjected to primary processing by the signal conditioning circuit 21, and the wireless transmission circuit 22 transmits the processing results to the upper computer.

Loading data by the upper computer, calibrating data peak values by using an algorithm, performing data filtering, processing the data into voltage values, and substituting the voltage values into a conversion matrix and a system transfer function determined by a calibration test, thereby obtaining three-dimensional force data and torsional moment.

The tool shank main body 1 needs to perform calibration test, and when cutting processing is performed, data of the piezoelectric film force sensor 7 and output data of the tool shank are collected, a transfer function of a system is determined according to the data, a matrix conversion coefficient from cutting force to voltage indication is determined, and a corresponding filtering method is provided.

The embodiment has simple structure, has small influence on the processing process, can monitor the three-dimensional cutting force signal and the two-way vibration signal in the cutting process, and can be matched with machine tool spindles of different types through split design.

Embodiment two:

the embodiment provides a system for measuring cutting force and cutting vibration in real time, which comprises an intelligent cutter handle and a machine tool, wherein the intelligent cutter handle is arranged on a main shaft of the machine tool.

The foregoing description is only of the preferred embodiments of the present application and is not intended to limit the same, but rather, various modifications and variations may be made by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims (10)

1. The intelligent knife handle is characterized by comprising a knife handle main body, wherein a circuit carrier for installing a data acquisition system is sleeved outside the knife handle main body, and a shell is arranged outside the circuit carrier; a plurality of detection beam structures are circumferentially distributed on the cutter handle main body, and piezoelectric film force sensors are fixed on the surfaces of the detection beam structures; and a plurality of vibration sensors are arranged on the side face of the circuit carrier, and the vibration sensors and the piezoelectric film force sensor are both connected with a data acquisition system.

2. The intelligent knife handle for measuring cutting force and cutting vibration in real time according to claim 1, wherein the circuit carrier body is cylindrical, and a plurality of mounting spaces are circumferentially formed in the circuit carrier body so as to form a mounting cavity of the data acquisition system with the housing.

3. The intelligent knife handle for measuring cutting force and cutting vibration in real time according to claim 2, wherein a plurality of grooves are formed in the side face of the bottom of the circuit carrier, and the vibration sensor is fixed in the grooves.

4. The intelligent knife handle for measuring cutting force and cutting vibration in real time according to claim 1, wherein the knife handle main body is circumferentially provided with a support beam structure, the cross section of the detection beam structure is of a cross-shaped structure, gaps are formed between adjacent beams, and the gaps are distributed in a groined-shaped structure.

5. The intelligent knife handle for measuring cutting force and cutting vibration in real time according to claim 1, wherein the data acquisition system comprises a signal amplifying circuit, an analog-to-digital conversion circuit, a signal conditioning circuit and a wireless transmission circuit which are sequentially connected, and the wireless transmission circuit is used for communicating with an upper computer;

the circuits are all connected with a power supply circuit, and the piezoelectric film force sensor and the vibration sensor are connected with a signal amplifying circuit.

6. The intelligent knife handle for measuring cutting force and cutting vibration in real time according to claim 5, wherein a power switch, a charging socket, a signal indicator lamp and a power indicator lamp which are connected with a power supply circuit are installed on the top of the shell.

7. The intelligent knife handle for measuring cutting force and cutting vibration in real time according to claim 6, wherein the signal indicator light is connected with the wireless transmission circuit so as to be lightened when the wireless transmission circuit is connected with the upper computer.

8. The intelligent knife handle for measuring cutting force and cutting vibration in real time according to claim 1, wherein the shell is composed of a side plate and a top plate and a bottom plate which are connected with the side plate.

9. The intelligent knife handle for measuring cutting force and cutting vibration in real time according to claim 1, wherein the tail end of the knife handle main body is connected with a collet, and the collet is connected with a cutter or a cap.

10. A system for measuring cutting forces and cutting vibrations in real time, comprising a machine tool and an intelligent shank according to any one of claims 1-9, said intelligent shank being mounted to a spindle of the machine tool.

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