Ultrasonic elliptical vibration drilling device and drilling method based on two-dimensional vibration of workpiece

Abstract

The invention relates to an ultrasonic elliptical vibration drilling device and a drilling method based on two-dimensional vibration of a workpiece. The device comprises a machine tool body, a feeding unit and a fixture unit. The fixture unit comprises a base, a vibration worktable installed on the base and a fixture installed on the vibration worktable. An ultrasonic elliptical vibration component is arranged beside the vibration worktable. The ultrasonic elliptical vibration component comprises an ultrasonic generator, a transverse longitudinal vibration transducer and a longitudinal longitudinal vibration transducer. The ultrasonic generator is connected to the transverse longitudinal vibration transducer and the longitudinal longitudinal vibration transducer via a waveguide respectively. The ultrasonic generator inputs high-frequency sinusoidal excitation with the same frequency and a phase difference to the transverse longitudinal vibration transducer and the longitudinal longitudinal vibration transducer respectively, so that the transverse longitudinal vibration transducer and the longitudinal longitudinal vibration transducer generate longitudinal vibration. The device applies elliptical vibration to the workpiece, and realizes precise control of the vibration trajectory by controlling the ultrasonic generator to control the amplitude and frequency, thereby improving the processing quality of drilling.

Description

Technical Field

[0001] The invention belongs to the technical field of drilling equipment, and relates to an ultrasonic elliptical vibration drilling device and a drilling method based on two-dimensional vibration of a workpiece. Background Art

[0002] In the 1990s, Japanese scholar Eiji Shamoto proposed ultrasonic elliptical vibration cutting technology. Unlike ordinary cutting, ultrasonic elliptical vibration is a two-dimensional vibration in an elliptical shape on the cutting plane, and produces a series of excellent cutting effects. A large number of studies have shown that compared with ordinary cutting, the ultrasonic elliptical vibration of the tool can significantly reduce processing defects, cutting forces and increase the plastic-brittle transition depth of brittle materials by reducing the actual chip thickness, the reverse effect of friction and the variable cutting angle / speed characteristics. At the same time, it minimizes the influence of the inherent characteristics of the machinable material on the machining performance, thereby significantly improving the machining efficiency and surface machining quality integrity, and improving the service life of the tool and the stability of the machining system.

[0003] Due to the excellent properties of two-dimensional ultrasonic vibration in machining difficult-to-machine materials, many scholars have begun to explore the combination of ultrasonic elliptical vibration and other machining methods. The machining method of ultrasonic elliptical vibration drilling has also been widely studied, and the influence of the trajectory on the machining quality in ultrasonic elliptical vibration drilling has also been paid attention to. Studies have shown that ultrasonic elliptical vibration drilling has a more obvious improvement in drilling performance than single ultrasonic vibration drilling (longitudinal vibration, torsional vibration drilling). However, in the research on ultrasonic elliptical vibration drilling, the drilling trajectory is mainly changed by the design of the amplitude rod. The disadvantage of this method is that the generated trajectory is limited to the designed amplitude rod and the generated trajectory cannot be accurately controlled. Summary of the invention

[0004] The invention provides an ultrasonic elliptical vibration drilling device based on two-dimensional vibration of a workpiece.

[0005] The solution adopted by the present invention to solve the technical problem is an ultrasonic elliptical vibration drilling device based on two-dimensional vibration of a workpiece, comprising a machine tool body, a feed unit installed on the machine tool body for driving a tool, and a fixture unit for fixing the workpiece, the fixture unit comprising a base, a vibration worktable installed on the base, and a fixture installed on the vibration worktable, an ultrasonic elliptical vibration component is arranged on the side of the vibration worktable, the ultrasonic elliptical vibration component comprises an ultrasonic generator, a transverse and longitudinal vibration transducer installed on the left or right side of the vibration worktable, and a longitudinal and longitudinal vibration transducer installed on the front or rear side of the vibration worktable, the ultrasonic generator is connected to the transverse and longitudinal vibration transducer and the longitudinal and longitudinal vibration transducer via a waveguide respectively, and the ultrasonic generator inputs high-frequency sinusoidal excitation with the same frequency and phase difference to the transverse and longitudinal vibration transducer and the longitudinal and longitudinal vibration transducer respectively, so that the transverse and longitudinal vibration transducer and the longitudinal and longitudinal vibration transducer generate longitudinal vibration.

[0006] Furthermore, the transverse longitudinal vibration transducer and the longitudinal longitudinal vibration transducer are both full-wavelength longitudinal vibration transducers.

[0007] Furthermore, a number of copper electrodes and piezoelectric ceramic sheets are spaced apart in the full-wavelength longitudinal vibration transducer, and the polarities of the adjacent two end surfaces of the piezoelectric ceramic sheets are the same. The transverse longitudinal vibration transducer and the longitudinal longitudinal vibration transducer are connected to the vibration workbench via a waveguide. Due to the inverse piezoelectric effect, the electrical signal of the ultrasonic generator is converted into mechanical vibration, and the vibration is transmitted to the vibration workbench via the waveguide.

[0008] Furthermore, the feed unit cooperates with the tapered hole of the machine tool spindle through a tapered shank, and the tapered shank is used to install the feed unit on the machine tool spindle through the traction of a pull nail. A rotating shaft coaxial with the tapered shank is fixedly installed below the tapered shank, and a rotating shaft spring chuck and a nut are installed at the lower end of the rotating shaft. A universal elastic chuck at the upper end of the tool is installed at the lower end of the rotating shaft, the nut is sleeved on the tool and locked by the nut, and the compression nut is fastened to the external thread at the lower end of the rotating shaft.

[0009] An ultrasonic elliptical vibration drilling method: a feed unit drives a tool thereon to process a workpiece on a vibration worktable, and an ultrasonic generator inputs high-frequency sinusoidal excitations with the same frequency and phase difference to a transverse longitudinal vibration transducer and a longitudinal longitudinal vibration transducer respectively, so that the transverse longitudinal vibration transducer and the longitudinal longitudinal vibration transducer generate longitudinal vibrations, the longitudinal longitudinal vibration transducer excites the longitudinal vibration mode of the vibration worktable, and the transverse longitudinal vibration transducer excites the vibration worktable to generate a bending vibration mode with the same frequency, and the vibrations in two directions are coupled to a fixture to form an elliptical trajectory.

[0010] Furthermore, the elliptical trajectory is changed by changing the phase difference in two directions emitted by the ultrasonic generator.

[0011] Compared with the prior art, the present invention has the following beneficial effects: simple structure, reasonable design, easy operation and use, and on the basis of the original ordinary drilling, elliptical vibration is applied to the workpiece, and the vibration trajectory is precisely controlled by controlling the amplitude and frequency of the ultrasonic generator, thereby improving the processing quality of the drilling. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The present invention is further described below in conjunction with the accompanying drawings.

[0013] Figure 1 It is a structural schematic diagram of the device.

[0014] Figure 2 It is a schematic diagram of the structure of the ultrasonic elliptical vibration component.

[0015] In the figure: 1-pull nail; 2-taper handle; 3-rotating shaft; 4-spring chuck; 5-nut; 6-tool; 7-vibration workbench; 8-base; 9-longitudinal vibration transducer; 10-waveguide belt; 11-ultrasonic generator; 12-transverse longitudinal vibration transducer. DETAILED DESCRIPTION

[0016] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments.

[0017] like Figure 1-2 As shown, an ultrasonic elliptical vibration drilling device based on two-dimensional vibration of a workpiece includes a machine tool body, a feed unit installed on the machine tool body for driving a tool, and a fixture unit for fixing the workpiece, wherein the fixture unit includes a base 8, a vibration worktable 7 installed on the base, and a fixture installed on the vibration worktable. An ultrasonic elliptical vibration component is arranged beside the vibration worktable, and the ultrasonic elliptical vibration component includes an ultrasonic generator 11, a transverse longitudinal vibration transducer 12 installed on the left or right side of the vibration worktable, and a longitudinal vibration transducer 12 installed on the front or rear side of the vibration worktable. To the longitudinal vibration transducer 9, the ultrasonic generator is connected to the transverse longitudinal vibration transducer and the longitudinal vibration transducer through the waveguide 10 respectively, and the ultrasonic generator inputs high-frequency sinusoidal excitation with the same frequency and phase difference to the transverse longitudinal vibration transducer and the longitudinal vibration transducer respectively, so that the transverse longitudinal vibration transducer and the longitudinal longitudinal vibration transducer generate longitudinal vibration. The waveguide is a sound transmitting medium with weak coupling characteristics in the non-sound transmitting direction, so that the two waveguides have high coupling efficiency in the orthogonal direction of sound transmission, so that the fixture can be excited to generate longitudinal vibration mode and bending vibration mode on the workbench.

[0018] In this embodiment, the transverse longitudinal vibration transducer and the longitudinal longitudinal vibration transducer are both full-wavelength longitudinal vibration transducers.

[0019] In this embodiment, the full-wavelength longitudinal vibration transducer includes a transducer body, and a front cover plate and a rear cover plate are respectively provided at the front and rear ends of the transducer body. The front cover plate and the rear cover plate are connected by connecting screws. A plurality of copper electrodes and piezoelectric ceramic sheets are spaced between the front cover plate and the rear cover plate. The front cover plate and the rear cover plate provide pre-tightening and pressing of the copper electrodes and the piezoelectric ceramic sheets through the connecting screws. The polarities of the adjacent two end surfaces of the piezoelectric ceramics are the same. The transverse longitudinal vibration transducer and the longitudinal longitudinal vibration transducer are connected to the vibration workbench via a waveguide. Due to its inverse piezoelectric effect, the electrical signal of the ultrasonic generator is converted into mechanical vibration, and the vibration is transmitted to the vibration workbench by using the waveguide.

[0020] In this embodiment, the feed unit cooperates with the tapered hole of the machine tool spindle through the tapered shank 2. The tapered shank installs the feed unit on the machine tool spindle through the traction of the pull nail 1. A rotating shaft 3 coaxial with the tapered shank is fixedly installed below the tapered shank. A rotating shaft spring chuck 4 and a nut 5 are installed at the lower end of the rotating shaft. A universal elastic chuck at the upper end of the tool 6 is installed at the lower end of the rotating shaft. The nut is sleeved on the tool and locked by the nut. The compression nut is fastened to the external thread at the lower end of the rotating shaft.

[0021] An ultrasonic elliptical vibration drilling method: a feed unit drives a tool thereon to process a workpiece on a vibration worktable, and an ultrasonic generator inputs high-frequency sinusoidal excitations with the same frequency and phase difference to a transverse longitudinal vibration transducer and a longitudinal longitudinal vibration transducer respectively, so that the transverse longitudinal vibration transducer and the longitudinal longitudinal vibration transducer generate longitudinal vibrations, the longitudinal longitudinal vibration transducer excites the longitudinal vibration mode of the vibration worktable, and the transverse longitudinal vibration transducer excites the vibration worktable to generate a bending vibration mode with the same frequency, and the vibrations in two directions are coupled to a fixture to form an elliptical trajectory.

[0022] In this embodiment, the elliptical trajectory is changed by changing the phase difference in two directions emitted by the ultrasonic generator, so as to accurately control the elliptical trajectory and achieve a good processing effect.

[0023] If this patent discloses or involves components or structural parts that are fixedly connected to each other, then, unless otherwise stated, the fixed connection can be understood as: a detachable fixed connection (for example, connected by bolts or screws), or as: a non-detachable fixed connection (for example, riveting, welding). Of course, the fixed connection can also be replaced by an integrated structure (for example, manufactured by a casting process) (except when it is obviously impossible to use an integrated forming process).

[0024] In the description of this patent, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing this patent, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this patent.

[0025] The preferred embodiments listed above further illustrate the objectives, technical solutions and advantages of the present invention in detail. It should be understood that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An ultrasonic elliptical vibration drilling method, using an ultrasonic elliptical vibration drilling device based on two-dimensional vibration of a workpiece, wherein the ultrasonic elliptical vibration drilling device based on two-dimensional vibration of the workpiece comprises a machine tool body, a feed unit mounted on the machine tool body for driving a tool, and a fixture unit for fixing the workpiece, characterized in that: The fixture unit includes a base, a vibration worktable installed on the base, and a fixture installed on the vibration worktable. An ultrasonic elliptical vibration component is arranged beside the vibration worktable. The ultrasonic elliptical vibration component includes an ultrasonic generator, a transverse longitudinal vibration transducer installed on the left or right side of the vibration worktable, and a longitudinal longitudinal vibration transducer installed on the front or rear side of the vibration worktable. The ultrasonic generator is connected to the transverse longitudinal vibration transducer and the longitudinal longitudinal vibration transducer via a waveguide belt, respectively. The ultrasonic generator inputs high-frequency sinusoidal excitation with the same frequency and phase difference to the transverse longitudinal vibration transducer and the longitudinal longitudinal vibration transducer, respectively, so that the transverse longitudinal vibration transducer and the longitudinal longitudinal vibration transducer generate longitudinal vibration; The transverse longitudinal vibration transducer and the longitudinal longitudinal vibration transducer are both full-wavelength longitudinal vibration transducers; A number of copper electrodes and piezoelectric ceramic sheets are spaced apart in the full-wavelength longitudinal vibration transducer, and the polarities of the adjacent two end surfaces of the piezoelectric ceramic sheets are the same. The transverse longitudinal vibration transducer and the longitudinal longitudinal vibration transducer are connected to the vibration workbench via a waveguide. Due to the inverse piezoelectric effect, the electrical signal of the ultrasonic generator is converted into mechanical vibration, and the vibration is transmitted to the vibration workbench via the waveguide. The feeding unit drives the tool thereon to process the workpiece on the vibration worktable, and the ultrasonic generator inputs high-frequency sinusoidal excitations with the same frequency and phase difference to the transverse and longitudinal vibration transducers and the longitudinal and longitudinal vibration transducers respectively, so that the transverse and longitudinal vibration transducers and the longitudinal and longitudinal vibration transducers generate longitudinal vibrations, the longitudinal and longitudinal vibration transducers excite the longitudinal vibration mode of the vibration worktable, and the transverse and longitudinal vibration transducers excite the vibration worktable to generate bending vibration modes with the same frequency, and the vibrations in two directions are coupled to the fixture to form an elliptical trajectory; the elliptical trajectory is changed by changing the phase difference in two directions emitted by the ultrasonic generator; The feed unit is matched with the tapered hole of the machine tool spindle through the tapered shank, and the tapered shank is used to install the feed unit on the machine tool spindle through the traction of the pull nail, and a rotating shaft coaxial with the tapered shank is fixedly installed below the tapered shank, and a rotating shaft spring chuck and a nut are installed at the lower end of the rotating shaft. The universal elastic chuck at the upper end of the tool is installed at the lower end of the rotating shaft, the nut is sleeved on the tool and locked by the nut, and the compression nut is fastened to the external thread at the lower end of the rotating shaft.

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