Abstract:
A modularized ultrasonic vibration machining apparatus is provided, which includes a tool holder module. The tool holder module further includes: a housing, having a positioning pin disposed thereon; a tool holder linking part, disposed in the housing; a transmitting mechanism, disposed in the housing and linked to the tool holder linking part in a transmission manner; an expanding device, disposed in the housing and linked to the transmitting mechanism in a transmission manner; a piezoelectric element, disposed in the housing and linked to the expanding device; and an electrical connector, disposed in the housing and electrically connected to the piezoelectric element and the positioning pin. Therefore, the modularized tool holder has an internal vibration mechanism and closed circuit setting of power supply, is capable of being assembled and applied conveniently, and has good security, economical efficiency, and applicability in industry.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit of Taiwan Patent Application No 098146250, filed on Dec. 31, 2009, which is hereby incorporated by reference for all purposes as if fully set forth herein. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Field of Invention 
         [0003]    The present invention relates to a machining apparatus, and more particularly to a modularized ultrasonic vibration machining apparatus capable of facilitating the modularized assembly and application of ultrasonic vibration machining and improving the stability and security of ultrasonic vibration machining. 
         [0004]    2. Related Art 
         [0005]    The principle of ultrasonic machining (USM) is that a high-frequency vibration tool of 15 kHz to 30 kHz contacts an article to be machined under a certain static pressure with supply of a mixture of an abrasive and water (abrasive slurry), in which the abrasive impacts the article to be machined through the vibration of the front end of the tool, and crushes the article to be machined into tine pieces, so as to remove the material. Generally speaking, the material of the ultrasonic machining is always selected to be a hard and brittle material, such as, glass and ceramics. Since it was unexpectedly found that ultrasound could be used to process in 1927, application of ultrasonic machining has decades of history in industry, and plays an important role in the field of non-conventional machining. 
         [0006]    It is difficult to perform conventional twist drilling in machining ceramic materials, and the drill always slips when contacting the workpiece, and resulting in problems of inclined cavity, poor roundness, and difficulties in cuttings excluded. In order to make the ultrasonic machining to be widely applied, with cost effectiveness into consideration, many scholars and experts began to improve the conventional twist drill or study novel methods for machining ceramic materials. Hocheng applied the conventional ultrasonic machining to drill cavities, and the roughness of the cavities, the smoothness and flatness of the edges of the cavity, and the cavity gap are improved significantly. Andrea Stoll found with experiments that, when the conventional drilling machine is assisted with ultrasound, the cuttings are easily cut, and the machining static pressure is low, the service life of the drill is long, and the removal rate of the material is high. 
         [0007]    In techniques disclosed in patents, the ultrasound-related patents are summarized as follows. (1) In Taiwan, R.O.C. Patent Publication No. 200836861, an ultrasonic resonance tool head structure is disclosed, which is mainly used to increase trenches on a side wall of a large-scaled ultrasonic tubular tool, after a high-frequency oscillation applied by the tool head is transferred to the tool, oscillation is generated in the trenches in the side wall of the tool, so as to improve the efficiency of the ultrasonic machining. 
         [0008]    (2) In China Patent No. 200720115929, an ultrasonic vibration tool head directly linked to a spindle of a numerical control tool machine is disclosed. The tool head has a brush as power contact. Although the contact is designed to be covered, the position of water outlet at the center does not have a waterproof design, such that the design is very unsafe. Furthermore, the rotation function is spindle driving rotation, but the tool head has a non-rotating part (i.e., the brush lead wires and the central water outlet), which is very dangerous when the non-rotating part and the rotating part are jammed. 
         [0009]    (3) In China Patent No. 200810199000, a vibration tool is disclosed, which mainly has a motor and a generator therein, such that ultrasonic vibration function is achieved without any external power supply, and power is directly transferred to the piezoelectric sheet in form of internal sensing. In such a structure, different functions are constructed in the same tool head, such that overall size is difficult to be miniaturized. Furthermore, since all the power structures are design in the tool head, the water through center is very dangerous and difficult. In addition, the vibration tool is a special spindle, and cannot be satisfied in a common machining spindle. 
         [0010]    It can be known that, the ultrasonic machining technology is still mainly applied to grind, drill, and polish brittle materials, and in metal machining, has poor integration with the conventional machine due to expensive equipment. In order to solve the problems, the present invention provides a modularized ultrasonic vibration machining apparatus, which is applicable to machining machines, so as to perform machining operations, such as grinding and polishing, milling, and drilling, and has the advantages of simple structure and being capable of effectively reducing the cost of the modularized ultrasonic vibration machining apparatus. 
       SUMMARY OF THE INVENTION 
       [0011]    The present invention is directed to a modularized ultrasonic vibration machining apparatus, which is capable of modularizing a tool holder assembled and used together with a machine and enables the modularized tool holder to have an internal vibration mechanism and closed circuit setting of power supply. When being assembled in a machine, the connection of the power path is completed at the same time, such that the modularized ultrasonic vibration machining apparatus has an efficacy of ultrasonic vibration machining, thus having excellent applicability in industry. 
         [0012]    The present invention is directed to a modularized ultrasonic vibration machining apparatus, which enables a modularized tool holder of a ultrasonic vibration machining to have excellent assembly performance and stability, and has a simple structure and secure connection design of power path, thus actively and effectively reducing the cost of the modularized ultrasonic vibration machining apparatus, and facilitating the application thereof. 
         [0013]    As embodied and broadly described herein, the technical solution employed by the present invention includes a tool holder module. The tool holder module further includes:
       a housing, having a positioning pin disposed thereon; a tool holder linking part, disposed in the housing; a transmitting mechanism, disposed in the housing and linked to the tool holder linking part in a transmission manner; an expanding device, disposed in the housing and linked to the transmitting mechanism in a transmission manner; a piezoelectric element, disposed in the housing and linked to the expanding device; and an electrical connector, disposed in the housing and electrically connected to the piezoelectric element and the positioning pin.       
 
         [0015]    The technical solution of the present invention further includes: a machining machine and a tool holder module. The machining machine includes: a spindle, having a positioning lock slot, in which the positioning lock slot is couple to a first power line. The tool holder module includes: a housing, having a positioning pin disposed thereon; a tool holder linking part, disposed in the housing, in which the tool holder linking part is assembled and linked to the spindle; an expanding device, disposed in the housing and driven by the tool holder linking part, a piezoelectric element, disposed in the housing and linked to the expanding device; an electrical connector, disposed in the housing and electrically connected to the piezoelectric element and the positioning pin, in which the electrical connector includes a linking part and a connecting part, the connecting part is pivoted to the linking part, and the connecting part achieves the electrical connection in a fixed state. With such structure, when the tool holder linking part is assembled with the spindle, the positioning pin and the positioning lock slot are linked, and the connection of the power path is completed. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0016]    The present invention will become more fully understood from the detailed description given herein below for illustration only, and thus are not !imitative of the present invention, and wherein: 
           [0017]      FIG. 1  is a schematic structural view of a preferred embodiment of the present invention; 
           [0018]      FIG. 2  is a partial schematic structural view of the present invention; 
           [0019]      FIG. 3  is a schematic structural view of assembling operation of the present invention; and 
           [0020]      FIG. 4  is a schematic structural view of a second embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0021]    In order to understand and know the structural features and efficacies of the present invention well, the present invention is illustrated in detail with reference to preferred embodiments accompanied with figures as follows. 
         [0022]      FIG. 1  is a schematic structural view of a preferred embodiment of the present invention. Referring to  FIG. 1 , a modularized ultrasonic vibration machining apparatus of this embodiment includes a tool holder module  1 . The tool holder module  1  is capable of being assembled on various machining machines, and the machining machine drives the tool holder module  1  to perform rotary machining. The tool holder module  1  further has the mechanism and function of ultrasonic vibration, such that the tool installed on the tool holder module  1  performs various types of machining such as grinding and punching in the manner of rotation and ultrasonic vibration, so as to improve the machining efficiency, and improving the surface conditions of the article to be machined. 
         [0023]    The tool holder module  1  is a standard tool holder of BT, 150, HSK (taper specification of table spindle cavity) or having other tool holder structures available in the market. The tool holder module  1  at least includes a housing  11  having an internal accommodating space, a tool holder linking part  10 , a transmitting mechanism  12 , an expanding device  14 , a piezoelectric element  16 , and an electrical connector  18 . The housing  11  contains a positioning block  17  at a side thereof, and the positioning block  17  has a positioning pin  171  disposed at an end thereof. The tool holder linking part  10  is disposed in the housing  11  and protruded out, a bearing  13  is disposed between the tool holder linking part  10  and the housing  11 . The transmitting mechanism  12  is assembled in the housing  11  and linked to an end of the tool holder linking part  10  in a transmission manner. In this embodiment, the transmitting mechanism  12  is a gear set  121  formed by gears engaged to one another, and the gear set  121  includes a first bevel gear  122 , a second bevel gear  123 , and a third bevel gear  124 . The first bevel gear  122  is linked to an end of the tool holder linking part  10  in a transmission manner and is driven by the tool holder linking part  10 . The first bevel gear  122  is perpendicular to and engaged with the second bevel gear  123 , and the second bevel gear  123  is perpendicular to and engaged with the third bevel gear  124 . The second bevel gear  123  is located on the housing  11  with a gear shaft  127 , and a receiving space  120  is formed among the first bevel gear  122 , the second bevel gear  123 , and the third bevel gear  124 . Furthermore, the transmitting mechanism  12  may be a belt drive pulley set or other directly driven transmitting mechanisms, so as to enable a spindle of the machining machine  2  to achieve the transmission and speed up effect through the transmitting mechanism  12  in the tool holder module  1 . 
         [0024]    The expanding device  14  is disposed in the housing  11 , and is linked to the transmitting mechanism  12  (third bevel gear  124 ) in a transmission manner, that is, the expanding device  14  may be driven by the transmitting mechanism  12  to rotate, and a bearing  19  is disposed between the expanding device  14  and the housing  11 , such that the expanding device  14  is capable of rotating smoothly. The expanding device  14  has an accommodating space  140  disposed therein. In a suitable implementation, the third bevel gear  124  has a gear shaft  125 , and the gear shaft  125  is inserted and linked in the accommodating space  140  of the expanding device  14 , so as to drive the expanding device  14  and to be located and supported. The gear shaft  125  further has a shaft space  126  penetrating the third bevel gear  124  at a central part of the gear shaft  125 . 
         [0025]    The piezoelectric element  16  is a material capable of deforming after being electrified (a piezoelectric material), and thus the piezoelectric element  16  of this embodiment may be a piezoelectric sheet or a piezoelectric vibrator. The piezoelectric element  16  is disposed in the accommodating space  140  of the expanding device  14 , for being linked to the expanding device  14 . In a suitable implementation, the piezoelectric element  16  is located at an outer side of the gear shaft  125 , such that the piezoelectric element  16  has a large operation range with respect to the expanding device  14 , and has a uniform and stable vibration (ultrasonic vibration) function. 
         [0026]    Referring to  FIG. 2 , the electrical connector  18  is disposed in the receiving space  120  of the transmitting mechanism  12 . The electrical connector  18  includes a linking part  181  and a connecting part  182  pivoted to the linking part  181 . The linking part  181  has a form of a rod terminal, and is disposed at a site in the shaft space  126  at an opposite end of the third bevel gear  124 . An isolating collar  15  is disposed between the linking part  181  and the third bevel gear  124 , such that the linking part  181  rotates with the third bevel gear  124 . The connecting part  182  is electrically connected to a power supply device, and the linking part  181  is electrically connected to the piezoelectric element  16  (described in detail below), for supplying power from the power supply device to the piezoelectric element  16 . Because the connecting part  182  is pivoted to the linking part  181 , the connecting part  182  is electrically connected to the power supply device in a fixed state (without rotating), so as to overcome the problem of power supply connection during the operation of the tool holder module  1 . As for the electrical connector  18 , the power transmission from the connecting part  182  in the fixed state to the linking part  181  in a rotating state may be achieved with a coaxial rotating electrical connector (for example, Model 205H, manufactured by Mercotac Inc, US). The power path of the rotating electrical connector is provided with low resistance by a liquid metal (such as mercury, not shown), in which the resistance is lower than 1 micro-ohm. Furthermore, the whole rotating electrical connector is completely sealed, and has high reliability by means of a ball bearing structure (not shown), thus preventing sparks generated during rotating. 
         [0027]    Referring to  FIG. 3 , the positioning pin  171  of the tool holder module  1  has a power line  31 , and the power line  31  passes through the internal space of the positioning block  17  (housing  11 ) and a shaft space  128  of the gear shaft  127 , enters the receiving space  120 , and forms a coupling positioning with the connecting part  182  of the electrical connector  18 . The positioning pin  171  of the positioning block  17  is coupled to the positioning lock slot  24  of the machining machine  2 . Accordingly, the positioning lock slot  24  is coupled to a power line  32 , and the power line  32  is coupled to a power source. Alternatively, a power supply device (not shown) installed in the machining machine  2  is utilized, such that a power is provided to the positioning lock slot  24  through the power line  32  (or other power paths), and thus the power of the power supply device is transferred to the connecting part  182  of the electrical connector  18  through the power line  32 , the positioning lock slot  24 , the positioning pin  171 , and the power line  31 . 
         [0028]    Referring to  FIG. 2  again, the third bevel gear  124  has a through hole  129  disposed therein, and the through hole  129  is located in the gear shaft  125 . In this embodiment, the through hole  129  is corresponding to a contact  161  of the piezoelectric element  16 . A lead  33  passes through the shaft space  126  and the through hole  129 , such that the power is transferred from the linking part  181  of the electrical connector  18  to the contact  161  of the piezoelectric element  16 . Alternatively, in another embodiment, the contact  161  of the piezoelectric element  16  may extend into the shaft space  126 , so as to be connected to the lead  33 . The lead  33  passes through the through hole  129 , and the power is transmitted from the linking part : 181  of the electrical connector  18  to the contact  161  of the piezoelectric element  16 , and thus the arrangement of the power path of the present invention is completed. 
         [0029]    The installation and operation of the modularized ultrasonic vibration machining apparatus of the present invention is described as follows. The tool holder module  1  is assembled on the spindle  21  (as shown in  FIG. 3 ) of the machining machine  2  (such as a conventional milling machine or a numerical control milling machine). The spindle  21  has a taper spindle cavity  22  disposed therein, and the spindle  21  has a positioning lock slot  24  disposed at a side opposite to the positioning pin  171  of the housing  11 . When the tool holder module  1  of the present invention is disposed in the machining machine  2 , the tool holder linking part  10  of the tool holder module  1  is assembled in the spindle cavity  22  of the spindle  21 , and the positioning pin  171  is positioned and fixedly linked to the positioning lock slot  24 , so as to position the housing  11  on the spindle  21 , such that the tool holder linking part  10  of the tool holder module  1  is capable of rotating with the spindle  21  integrally. Furthermore, the expanding device  14  of the tool holder module  1  has a fixture  23  (such as a sleeve), disposed at an end thereof. The fixture  23  is used for clamping any machining tool (not shown) to perform ultrasonic vibration machining operation. 
         [0030]    The spindle  21  of the machining machine  2  drives the tool holder linking part  10  to rotate, the tool holder linking part  10  drives the first bevel gear  122  of the transmitting mechanism  12  to rotate, and the first bevel gear  122  drives the second bevel gear  123 , the third bevel gear  124 , and the expanding device  14  to rotate, such that the fixture  23  connected to the expanding device  14  and the machining tool clamped by the fixture  23  are enabled to rotate, so as to perform machining operation and application, such as grinding and polishing, milling, and drilling. 
         [0031]    In the present invention, the tool holder module  1  is assembled with the spindle  21  of the machining machine  2 , the positioning pin  171  and the positioning lock slot  24  are combined and positioned, such that the connection of external power source (power lines  31 ,  32 ) is completed simultaneously. The power is introduced to the piezoelectric element  16  through the electrical connector  18 , and the piezoelectric element  16  deforms when being electrified, such that the expanding device  14  is enabled to generate vibration (or ultrasonic vibration), and thus the machining tool connected to the expanding device  14  is capable of perform machining operation and application, such as (ultrasonic) vibration grinding and polishing/milling/drilling. 
         [0032]    Moreover, the power introduced to the piezoelectric element  16  by the electrical connector  18  may be transferred by a coaxial rotating electrical connector, so as to eliminate the risk of explosion caused by sparks of conventional carbon brush in high dust environment. 
         [0033]    Furthermore, the present invention may also carry a high-performance transmitter, so as to automatically search frequency or automatically reset or automatically reset to search frequency according to change of the resonance frequency with the machining process, such that the machining efficiency is always maintained at an optimal state. The present invention may further be provided with the capacity of high-pressure water through center, such that high-pressure water still removes the cuttings powerfully and cooling the machining area effectively, even when the machining structure is thin, small, and deep during micro machining. 
         [0034]    Referring to  FIG. 4 , a schematic structural view of a second embodiment of the present invention is shown, in which the same parts as those in the tool holder module  1  shown in  FIG. 1 ,  FIG. 2 , and  FIG. 3  are marked with the same reference numerals, and are not repeated herein. As shown in  FIG. 4 , a tool holder module  1 ′ according to the second embodiment is approximately the same as the tool holder module  1  of the first embodiment, and the difference lies in that a transmitting mechanism  12 ′ of this embodiment is constructed by a belt drive pulley set  321 . The belt drive pulley set  321  includes a first belt drive pulley  322 , a second belt drive pulley  323 , and a third belt drive pulley  324 . The first belt drive pulley  322  is linked to one end of the tool holder linking part  10  to be driven thereby, the first belt drive pulley  322  is connected with the second belt drive pulley  323  through a first transmitting belt  325  to move simultaneously, and the second belt drive pulley  323  is connected with the third belt drive pulley  324  through a second transmitting belt  326  to move simultaneously. The second belt drive pulley  323  is pivoted to the housing  11  (the positioning block  17 ) through a rotating shaft  327  thereof, so as to enable a spindle of the machining machine  2  to achieve the transmission and speed up effect through the transmitting mechanism  12 ′ in the tool holder module  1 ′. 
         [0035]    Similarly, the expanding device  14  (such as an expander) is linked to the third belt drive pulley  324  of the transmitting mechanism  12 ′, that is to say, the expanding device  14  can be driven by the transmitting mechanism  12 ′ to rotate, and the expanding device  14  has an accommodating space  140  disposed therein. In a suitable implementation, the third belt drive pulley  324  has an axis  328 , and the axis  328  is linked to the expanding device  14  by inserting in the accommodating space  140  of the expanding device  14 , for driving the expanding device  14  and obtaining positioning support. The axis  328  further has a shaft space  329  penetrating the third belt drive pulley  324  disposed at the central part thereof. In this embodiment, the piezoelectric element  16  is sandwiched between the expanding device  14  and the transmitting mechanism  12 ′ (the third belt drive pulley  324 ). The manner of supplying power of the power supply device to the piezoelectric element  16  is the same as that in the first embodiment, and is not repeated herein. 
         [0036]    When the modularized ultrasonic vibration machining apparatus of the present invention performs ultrasonic vibration machining operation, the spindle  21  of the machining machine  2  drives the tool holder linking part  10  to rotate, the tool holder linking part  10  drives the first belt drive pulley  322  of the transmitting mechanism  12 ′ to rotate, and the first belt drive pulley  322  further drives the second belt drive pulley  323 , the third belt drive pulley  324  and the expanding device  14  to rotate, such that the fixture  23  connected to the expanding device  14  and the machining tool clamped by the fixture  23  are enabled to rotate, so as to perform machining operation and application, such as grinding and polishing, milling, and drilling. 
         [0037]    It can be known from the above that, the modularized ultrasonic vibration machining apparatus of the present invention enables the original machining machine to generate rotary machining and ultrasonic vibration machining, thus effectively improving the machining efficiency, and improving the surface situation of the article to be machined. In the present invention, due to the arrangement of power path in the effective, when the tool holder module is installed in the machining machine, the input path design of the external power source is completed simultaneously through the positioning and linking of the positioning pin and the positioning lock slot, such that the modularized design of the ultrasonic vibration tool holder is achieved, and has the positive advantages of simple structure, flexible application, and low cost, thus having excellent applicability in industry. 
         [0038]    The above description is only a preferred embodiment of the present invention, but is not intended to limit the scope of implementation of the present invention. Any equivalent variations and modifications made according to the shapes, structures, features, and spirit of the scope of the claims of the present invention fall within the scope of the claims of the present invention.