Description

TAPPING SHANK AND NUT TAPPING APPARATUS WHICH

USED THIS

Technical Field

[1] The present invention relates to a tapping shank and a nut tapping apparatus using the tapping shank, and more particularly, to a tapping shank, which allows nut tapping to be performed by a tap formed in the front end of the tapping shank, oil and chips on the nut to be separated from each other while the tapped nut is moved along the tapping shank, and the nut to be removed from the tapping shank without being scattered, and a nut tapping apparatus using the tapping shank. Background Art

[2] In general, a nut tapping apparatus for nut tapping to the inner circumferential surface of the nut rotates a tapping shank, which includes a tap at the front end thereof, and continuously provides the nuts to the tapping shank. Then, tapping is performed in the inner circumferential surface of the nut provided by the tapping shank and the nuts are moved along the tapping shank.

[3] FIG. 12 illustrates a conventional nut tapping apparatus and FIG. 13 illustrates the operation according to a rotation of a tapping shank 100 in the nut tapping apparatus illustrated in FIG. 12. Referring to FIGS. 12 and 13, the conventional nut tapping apparatus includes the tapping shank 100, a clamp 200, an operating means 300, and a pusher 400. The tapping shank 100 includes a tap 110 at the front end thereof for nut tapping in a nut N and includes a bend part 150 bent to one side at the rear end thereof. The operating means 300 includes a sleeve 310 in which the tapping shank 100 is spaced apart therefrom by a predetermined interval and is fixed to the tapping shank 100.

[4] The conventional nut tapping apparatus is manufactured as follows.

[5] First, the tapping shank 100 rotates at high speed by the operating means 300. Then, the nut N, in which nut tapping is not performed, is placed in the clamp 200. The clamp 200 is slide moved to the front end of the tapping shank 100 by the pusher 400. Here, the nut N passes through the tap 110 of the tapping shank 100 and nut tapping is accomplished in the inner circumferential surface of the nut N. Then, the nut N passes through the tap 110 so as to move along the tapping shank 100 and is removed from the tapping shank 100 through the bend part 150.

[6] However, in the conventional nut tapping apparatus, oil and chips covered on the nut

N are removed with the nut N while the nut N is removed through the bend part 150. In addition, oil and chips should be separated from the nut N covered with oil and chips

by using an oil hydrator.

[7] In addition, the nuts N removed through the bend part 150 due to rotation force of the tapping shank 100 spring to various directions. Then, the nuts N hit the frames of the apparatus and make noisy. In addition, since the nuts N hit the frames of the apparatus, the exterior of the nuts N or the frames of the apparatus may be damaged. Moreover, due to such damage, defect rate of products and the maintenance cost increase may increase.

Disclosure of Invention Technical Problem

[8] The present invention provides a tapping shank which separates oil and chips from nuts without using a separate oil hydrator and separately removes the separated oil and chips, and a nut tapping apparatus using the tapping shank.

[9] The present invention also provides a tapping shank which allows a nut, in which nut tapping is accomplished, to be dropped by a free fall method without being affected by the rotation force, while the nuts are removed from the tapping shank, and a nut tapping apparatus using the tapping shank.

[10] The present invention also provides a tapping shank which prevents noise generated when the nuts, to which nut tapping is accomplished, are removed from the tapping shank, and a nut tapping apparatus using the tapping shank.

[11] The present invention also provides a tapping shank which prevents the exterior of the nuts removed from the tapping shank or a frame of a nut tapping apparatus from being damaged and reduces defect rate of products and the maintenance cost of the nut tapping apparatus, and the nut tapping apparatus using the tapping shank. Technical Solution

[12] According to an aspect of the present invention, there is provided a tapping shank for nut tapping in a drive shaft while rotating based on the drive shaft, the tapping shank including: a moving part in a straight form in which a tap for nut tapping is formed at the front end of the moving part, the moving part having a cross-section in the shaft direction of a square or a trapezoid form; a curve part extended from the rear end of the moving part and curved in a semicircular form; and a horizontal part extended from the rear end of the curve part to the shaft direction in parallel with the moving part.

[13] According to another aspect of the present invention, there is provided a nut tapping apparatus in which nuts, to which nut tapping is not accomplished, are moved from a hopper of a base body, the nuts are supplied to a tap rotated based on a drive shaft by the force for transmitting a pusher from a driving pulley, and nut tapping is accomplished to the nuts by the tap, the apparatus including: a tapping shank comprising: a moving part in a straight form in which the tap for nut tapping is formed at the front

end of the moving part; a curve part extended from the rear end of the moving part and curved in a semicircular form; and a horizontal part extended from the rear end of the curve part to the shaft direction in parallel with the moving part; and a tapping shank rotating means rotating the tapping shank, in which the moving part, the curve part, and the horizontal part included in the tapping shank are placed, a moving path is penetrated so as for the nuts, to which nut tapping is accomplished, to be moved along the tapping shank, an oil and chip discharge unit is penetrated from the moving path to the out side in correspondence to a flexure point of the curve part having the maximum value of a radius of rotation from the drive shaft, and the driving pulley is combined to the part where the moving part penetrates.

[14] The apparatus may further include a groove part depressed along the moving path in the tapping shank rotating means to which the tapping shank is inserted into the groove part so as for the flexure point of the curve part and the oil and chip discharge unit to correspond to each other.

[15] The apparatus may further include an open-and-close panel in the tapping shank rotating means, the open-and-close panel including a nut discharge unit so as for the nuts, to which nut tapping is accomplished, to be moved along the horizontal part and being combined to the groove part or the rear end of the tapping shank rotating means.

[16] The tapping shank rotating means may include a sleeve including a first moving path at the center so as for the nuts moving along the moving part to be moved; and a tapping shank rotating body interconnecting with a second moving path, the groove part, and the oil and chip discharge unit, the second moving path penetrating the center thereof in correspondence to the first moving path, the groove part being depressed for the curve part including the nuts to be inserted, and the oil and chip discharge unit being formed in correspondence to the flexure point of the curve part, wherein the tapping shank rotating body is combined to the rear end of the sleeve so as for the first moving path and the second moving path to be interconnected to each other.

[17] The apparatus may further include an open-and-close panel in the tapping shank rotating means in which a nut discharge unit is formed so as for the nuts to be moved along the horizontal part, wherein the open-and-close panel is combined to the groove part or the rear end of the tapping shank rotating means.

[18] The tapping shank rotating body and the open-and-close panel may be combined to each other as a single body and may be divided into two based on the tapping shank so as to form a pair of tapping shank fixing bodies which are combined to each other, wherein the second moving path, the oil and chip discharge unit, the groove part, and the nut discharge unit are divided into two to respectively correspond to each other in the tapping shank fixing bodies, and wherein at least any one of the pair of tapping shank fixing bodies are formed at the rear end of the sleeve to interconnect with the

first moving path and the second moving path.

[19] The moving part and the horizontal part may be placed at the same straight line, the rear end of the horizontal part may be placed in a tapping shank retard means rotating with the tapping shank according to back-and- forth movement of the tapping shank by the pusher, and the tapping shank retard means may be spaced apart from the rear end of the tapping shank rotating means in correspondence with the back-and-forth movement of the tapping shank.

[20] The apparatus may further include an oil recycling means including a first hopper, a chip separator, an oil container, and a second hopper, wherein the first hopper is formed at the lower side of the tap for nut tapping, the chip separator connected with the first hopper separates chips generated during nut tapping from oil flowing from the first hopper, the oil container stores oil, from which the chips are separated through the chip separator, and the second hopper is formed at the lower side of the tapping shank rotating means in correspondence to the oil and chip discharge unit and is connected with the chip separator or the oil container.

Advantageous Effects

[21] According to the present invention, a tapping shank which separates oil and chips from nuts without using a separate oil hydrator and separately removes the separated oil and chips, and a nut tapping apparatus using the tapping shank are provided.

[22] According to the present invention, a tapping shank which allows the nuts, in which nut tapping is accomplished, to be dropped by a free fall method without being affected by the rotation force, while the nuts are removed from the tapping shank, and a nut tapping apparatus using the tapping shank are also provided.

[23] According to the present invention, a tapping shank which prevents noise generated when the nuts, to which nut tapping is accomplished, are removed from the tapping shank, and a nut tapping apparatus using the tapping shank are also provided.

[24] According to the present invention, a tapping shank which prevents the exterior of the nuts removed from the tapping shank or a frame of a nut tapping apparatus from being damaged and reduces defect rate of products and the maintenance cost of the nut tapping apparatus, and the nut tapping apparatus using the tapping shank are also provided.

[25] According to the present invention, a tapping shank which separates oil and chips from the nuts during nut tapping using the rotation force of the tapping shank, without using a separate oil hydrator, and a nut tapping apparatus using the tapping shank are also provided.

[26] According to the present invention, a tapping shank which can be rapidly and conveniently replaced when the tap is worn during nut tapping, and a nut tapping

apparatus using the tapping shank are also provided. [27] According to the present invention, a tapping shank which prevents the nuts moved along a curve part from colliding with the inner wall of a groove part when the curve part moves back-and- forth in the groove part of a tapping shank rotating body and prevents the exterior of the nuts being damaged, and a nut tapping apparatus using the tapping shank are also provided. [28] According to the present invention, a tapping shank which can be stably supported when the tapping shank rotates and a nut tapping apparatus using the tapping shank are also provided.

Brief Description of Drawings [29] FIG. 1 illustrates a nut tapping apparatus according to an embodiment of the present invention; [30] FIG. 2 is a perspective view of a tapping shank used in the nut tapping apparatus of

FIG. 1; [31] FIG. 3 illustrates a tapping shank being installed in the nut tapping apparatus of FIG.

1; [32] FIG. 4 illustrates a rear view of a tapping shank rotating body in the nut tapping apparatus of FIG. 1 ; [33] FIG. 5 is a cross-sectional diagram of the tapping shank rotating body of FIG. 4 taken along the line I-I of FIG. 4; [34] FIG. 6 is a perspective view of a tapping shank rotating body in the nut tapping apparatus of FIG. 1 ; [35] FIG. 7 illustrates a nut tapping apparatus according to another embodiment of the present invention; [36] FIG. 8 is a perspective view of a tapping shank rotating means in the nut tapping apparatus of FIG. 7; [37] FIG. 9 illustrates a tapping shank being installed in the nut tapping apparatus of FIG.

7; [38] FIG. 10 illustrates an operated state of the tapping shank rotated in the nut tapping apparatus of FIG. 7; [39] FIG. 11 is a perspective view of a tapping shank rotating means in a nut tapping apparatus according to another embodiment of the present invention; [40] FIG. 12 illustrates a conventional nut tapping apparatus; and

[41] FIG. 13 illustrates an operated state of a tapping shank rotated in the nut tapping apparatus of FIG. 12.

Best Mode for Carrying out the Invention [42] In one or more embodiments, like elements denote like reference numerals and are

described in the first embodiment. Elements other than those in the first embodiment are described in another embodiments.

[43] Hereinafter, a tapping shank 10 and a nut tapping apparatus using the tapping shank

10 according to an embodiment will be described more fully with reference to the accompanying drawings.

[44] FIG. 1 illustrates a nut tapping apparatus according to an embodiment of the present invention. Referring to FIG. 1, the nut tapping apparatus according to the current embodiment includes a base body 90, a tapping shank 10 installed to the base body 90 rotating for nut tapping to nuts N, and a tapping shank rotating means 20 providing the rotation force to the tapping shank 10.

[45] The base body 90 supports the nut tapping apparatus at the bottom and includes a hopper 91, a supply rail 92, a pusher 93, and a clamp 94, which will be described with reference to FIG. 7. The hopper 91 is installed at the upper side of the base body 90 and includes the nuts N, to which nut tapping is not accomplished. The supply rail 92 is connected to the hopper 91 and supplies the nuts N included in the hopper 91 to the clamp 94 (refer to FIG. 7). The pusher 93 has a cylinder form and the slide moves the nuts N placed in the clamp 94 to a tap 11 of the tapping shank 10. The nuts N supplied through the supply rail 92 are placed in the clamp 94 (refer to FIG. 7).

[46] FIG. 2 is a perspective view of the tapping shank 10 used in the nut tapping apparatus of FIG. 1. Referring to FIG. 2, the tapping shank 10 performs nut tapping to the inner circumferential surface of the nut N by using the rotation force supplied by a motor 80, which will be described later. The tapping shank 10 may be formed of the tap 11, a moving part 13, a curve part 15, and a horizontal part 17.

[47] The tap 11 rotates based on a drive shaft and performs nut tapping to the nut N placed in the clamp 94 (refer to FIG. 7). A horizontal section in a drive shaft direction has a square or a trapezoid form and the tap 11 performs nut tapping to the inner circumferential surface of the nut N. Here, the drive shaft is a virtual shaft indicating the center of the rotating tap 11.

[48] The moving part 13 is a straight rod to which the tap 11 is combined to the front end of the moving part 13. Here, the center shaft of the moving part 13 may be on the same straight line with the drive shaft. The moving part 13 penetrates and is supported by a sleeve 30, which will be described later, while the tapping shank 10 rotates, so that the tap 11 is prevented from being shaken and thus stably rotates, thereby improving precision of nut tapping.

[49] The curve part 15 extends from the rear end of the moving part 13 and and curves in a semicircular form. The upper most part (the part parallel to the center axis of the moving part 13 from among tangent lines formed on the curved surface of the curve part 15) curved in the semicircular- form curve part 15 is denotes a flexure point 16.

[50] The horizontal part 17 extends from the rear end of the curve part 15 in parallel with the center axis of the moving part 13. In particular, the center axis of the horizontal part 17 may be disposed on the same straight line with the center axis of the moving part 13.

[51] The moving part 13, the curve part 15, and the horizontal part 17 indicate a path of the nut N, to which nut tapping is accomplished by the tap 11, being fixed and moved. Since the nut N moves along the moving part 13, the curve part 15, and the horizontal part 17, modification of the nut N may not be generated.

[52] In order to rotate the tapping shank 10, the tapping shank rotating means 20 is combined to the tapping shank 10 as one body.

[53] The moving part 13, the curve part 15, and the horizontal part 17 of the tapping shank 10 are placed at the center of the tapping shank rotating means 20 and a moving path 21 penetrates the tapping shank rotating means 20 so as for the nut N, in which nut tapping is accomplished by the tap 11, to move along the moving part 13, the curve part 15, and the horizontal part 17 of the tapping shank 10. Also, an oil and chip discharge unit 44 corresponds to the flexure point 16 of the curve part 15 and is penetrated from the moving path 21 to the outside. Here, the center of the moving path 21, where the moving part 13 penetrates, becomes the drive shaft. In addition, a driving pulley 82 rotating by the motor 80 is combined to the part (the sleeve 30 which will be described later), where the moving part 13 penetrates, in the tapping shank rotating means 20. Then, the tapping shank rotating means 20 rotates along with the driving pulley 82 and the tapping shank 10 rotates according to rotation of the tapping shank rotating means 20.

[54] In the tapping shank rotating means 20, a groove part 43 depressed along the moving path 21 is further formed so that the rear end of the tapping shank 10 may be inserted into the groove part 43. The groove part 43 allows the moving path 21 to connect with the oil and chip discharge unit 44. Also, the curve part 15 or the curve part 15 and the horizontal part 17 may be placed in groove part 43.

[55] In addition, the tapping shank rotating means 20 further includes an open-and-close panel 50 inserted into and combined to the groove part 43 or combined to the rear end of the tapping shank rotating means 20 and thus supports the inserted tapping shank 10. The open-and-close panel 50 includes a nut discharge unit 51. The horizontal part 17 of the tapping shank 10 is placed in the nut discharge unit 51 so that the tapping shank 10 is supported and the nuts N, in which nut tapping is accomplished, move along the horizontal part 17.

[56] FIG. 3 illustrates the tapping shank 10 being installed in the nut tapping apparatus of

FIG. 1, FIG. 4 illustrates a rear view of a tapping shank rotating body 40 in the nut tapping apparatus of FIG. 1, FIG. 5 is a cross-sectional diagram of the tapping shank

rotating body 40 of FIG. 4 taken along the line I-I of FIG. 4, and FIG. 6 is a perspective view of the tapping shank rotating body 40 in the nut tapping apparatus of FIG. 1. Referring to FIGS. 3 through 6, the tapping shank rotating means 20 may include the sleeve 30, the tapping shank rotating body 40, and the open-and-close panel 50 which are combined to each other.

[57] The sleeve 30 includes a pillar-form first moving path 31 penetrating the sleeve 30 at the center, the first moving path 31 having a cross section in a drive shaft direction of a polygon or a round shape. The moving part 13 of the tapping shank 10 is placed in the first moving path 31 so as to support the tapping shank 10. Also, the first moving path 31 is a hole which allows the nuts N, in which nut tapping is accomplished by the tap 11, to move along the moving part 13.

[58] The sleeve 30 includes the driving pulley 82 driven by the motor 80 and rotates by the rotation force of the motor 80. More specifically, a boss 83, to which the sleeve 30 is inserted and fixed, is installed and the boss 83 is fixed to the driving pulley 82. In addition, a bearing 84 is installed to the outer peripheral surface of the boss 83 so as for the sleeve 30 to be rotated. The bearing 84 is installed and fixed to a bearing housing 85. The bearing housing 85 is fixed to a bracket 86 installed to the base body 90 and supports rotation of the sleeve 30. Here, the driving pulley 82 is connected with the motor 80 generating rotation force and a belt 81 and receives the rotation force from the motor 80. Then, the sleeve 30 rotates by the rotation force of the driving pulley 82, while the sleeve 30 is supported by the sleeve 30.

[59] The tapping shank rotating body 40 is combined to the rear end of the sleeve 30 and the curve part 15 of the tapping shank 10 is placed in the tapping shank rotating body 40 so that tapping shank 10 rotates by the rotation force of the sleeve 30. In the drawings, the tapping shank rotating body 40 is fixed to the rear end of the sleeve 30 through a fixing hole 46 using a bolt.

[60] A second moving path 42 penetrates the center of the tapping shank rotating body 40 in correspondence to the first moving path 31 of the sleeve 30. The groove part 43 is formed at the rear end of the tapping shank rotating body 40 and thus the tapping shank

10 (in particular, the curve part 15) is inserted into the groove part 43. In addition, the

011 and chip discharge unit 44 is penetrated from the groove part 43 to the outside in correspondence to the flexure point 16 of the curve part 15 inserted into the groove part 43. Then, the second moving path 42, the groove part 43, and the oil and chip discharge unit 44 are mutually communicated. The second moving path 42, the groove part 43, and the oil and chip discharge unit 44 according to the current embodiment are formed of an aperture interconnecting the front surface, the side surface, and the rear surface of the tapping shank rotating means 20 as illustrated in FIG. 6.

[61] The curve part 15 of the tapping shank 10 may move back-and-forth along the drive

shaft direction in the groove part 43 included in the tapping shank rotating body 40.

[62] The open-and-close panel 50 is combined to the groove part 43 by a hinge 52 and is rotated to the rear end of the tapping shank rotating body 40 so as to open and close the groove part 43. The open-and-close panel 50 prevents the curve part 15 placed in the groove part 43 of the tapping shank rotating body 40 from being separated from the groove part 43, allows the tapping shank 10 to stably rotate based on the drive shaft, and includes the nut discharge unit 51 penetrated at the center of the open-and-close panel 50. The nut discharge unit 51

[63] The nut discharge unit 51 allows the horizontal part 17 of the tapping shank 10 to be placed therein and the nuts N, to which nut tapping is accomplished, to move along the horizontal part 17.

[64] A fixture 53 having tension due to a spring 54 is formed on one side of the rear cross section of the tapping shank rotating body 40, in order to fix the open-and-close panel 50 in a closed state. Also, a hanger part 55 is formed to support the fixture 53 to the tapping shank rotating means 20 and a groove 56 for conveniently controlling the fixture 53 is formed on the open-and-close panel 50 corresponding to the end part of the fixture 53.

[65] The first moving path 31, the groove part 43, and the nut discharge unit 51 according to the current embodiment becomes the moving path 21.

[66] Hereinafter, a process of replacing the tapping shank 10 in the nut tapping apparatus according to the current embodiment is described.

[67] When the tap 11 installed at the front end of the tapping shank 10 is worn during nut tapping, if the fixture 53 is pushed to one side, the spring 54 is compressed and the front end of the fixture 53 is separated from the groove 56. Here, the open-and-close panel 50 rotates based on the hinge 52 and opens the groove part 43 of the tapping shank rotating body 40. Then, when the tapping shank 10 is taken out to the rear end of the tapping shank rotating means 20, the tapping shank 10, in which tap 11 is worn, may be easily separated from the tapping shank rotating means 20.

[68] The nut N, to which nut tapping is accomplished, is placed in the moving part 13, the curve part 15, and the horizontal part 17 of the tapping shank 10, in which the tap 11 is not worn, and the tapping shank 10 is inserted into the groove part 43 of the tapping shank rotating body 40. Then, the tap 11 of the tapping shank 10 penetrates the groove part 43, the second moving path 42, and the first moving path 31 and thus, faces the pusher 93 or the clamp 94 (refer to FIG. 7). Also, the open-and-close panel 50 rotates based on the hinge 52 and thus is placed in the groove part 43 of the tapping shank rotating body 40. Here, the front end of the fixture 53 is inclined as illustrated in the drawing so that while the open-and-close panel 50 is placed in the groove part 43 of the tapping shank rotating body 40 according to the rotation of the open-and-close

panel 50, the fixture 53 is pushed to one side and the front end of the fixture 53 is placed in the groove 56 by the spring 54, thereby fixing the open-and-close panel 50. Then, a new tapping shank 10, in which the tap 11 is not worn, is placed in the tapping shank rotating means 20. Here, the moving part 13 is placed in and supported by the first moving path 31 of the sleeve 30, the curve part 15 is placed in and supported by the groove part 43 of the tapping shank rotating body 40, and the horizontal part 17 is placed in and supported by the nut discharge unit 51 of the open-and-close panel 50.

[69] Hereinafter, a nut tapping process in the nut tapping apparatus according to the current embodiment is described.

[70] The nuts N, to which nut tapping is not accomplished, are applied to the hopper 91 of the base body 90. The nuts N supplied to the hopper 91 are placed in the clamp 94 (refer to FIG. 7) along the supply rail 92. When the nuts N are placed in the clamp 94 (refer to FIG. 7), the pusher 93 operates to slide move the clamp 94 (refer to FIG. 7) toward the tap 11 of the tapping shank 10. Here, as described above, the tapping shank

10 is inserted into and placed in the tapping shank rotating means 20 is rotated at highspeed by the rotation force of the driving pulley 82.

[71] According to the pusher 93 being operated, the clamp 94 (refer to FIG. 7) continuously slide-moves and nut tapping is accomplished to the nuts N placed in the clamp 94 (refer to FIG. 7) by the rotating tap 11. Here, for convenience of the process,

011 is supplied from an oil container 75 (refer to FIG. 7) and the nuts N are covered with supplied oil. During nut tapping, chips are generated and the nuts N are covered with some of the chips along with supplied oil.

[72] The nuts N covered with oil and chips pass through the moving part 13, the curve part 15, and the horizontal part 17 and discharge to the nut discharge unit 51. Here, while the nuts N covered with oil and chips pass through the curve part 15, oil and chips are separated from the nuts N due to the centrifugal force generated by the rotation force of the tapping shank 10. More specifically, the curve part 15 curves in a semicircular form. When the tapping shank 10 rotates, the centrifugal force changes according to inclination of the tangent lines formed on the curved surface of the curve part 15. That is, the centrifugal force has the minimum value in the front end and the rear end of the curve part 15 and has the maximum value in the flexure point 16 of the curve part 15. Accordingly, when the nuts N covered with oil and chips move along the curve part 15, the nuts N lean to the flexure point 16 of the curve part 15, where the maximum centrifugal force is generated, and oil and chips are separated from the nuts N by the centrifugal force of the curve part 15. The nuts N moved along the tapping shank 10 by the nuts N, to which nut tapping is accomplished, continuously supplied from the front end of the tapping shank 10 gradually move toward the rear end of the horizontal part 17 and are discharged through the nut discharge unit 51.

[73] Here, the horizontal part 17 is located on the same line with the moving part 13 so that the nuts N separated from the horizontal part 17 are not interrupted by the rotation force of the tapping shank 10. Thus, when the nuts N, to which nut tapping is accomplished, are taken out from the tapping shank 10, the nuts N fall free and are discharged through the nut discharge unit 51 without being scattered all over the place. Then, the exterior of the nuts N and the frame of the base body 90 are prevented from being damaged. In addition, separately removing of oil from the nuts N is not needed.

[74] The oil and chips separated while passing through the curve part 15 are discharged outside of the tapping shank rotating means 20 through the oil and chip discharge unit 44 and are collected in a separate hopper 72 (refer to FIG. 7). A separation process is performed to the collected oil and chips and separated oil may be reused. Mode for the Invention

[75] Hereinafter, a tapping shank and a nut tapping apparatus using the tapping shank according to another embodiment will be described more fully with reference to the accompanying drawings.

[76] FIG. 7 illustrates the nut tapping apparatus according to another embodiment of the present invention and FIG. 8 is a perspective view of a tapping shank rotating means in the nut tapping apparatus of FIG. 7.

[77] Referring to FIGS. 7 and 8, the nut tapping apparatus according to the current embodiment is same as the nut tapping apparatus according to the previous embodiment.

[78] In other word, the tapping shank 10 according to the current embodiment includes the tap 11, the moving part 13, the curve part 15, and the horizontal part 17, as described in the previous embodiment.

[79] Also, the tapping shank rotating means 20 according to the current embodiment includes the sleeve 30, the tapping shank rotating body 40, and the open-and-close panel 50, as described in the previous embodiment. However, the open-and-close panel 50 according to the current embodiment is combined to the rear end of the tapping shank rotating body 40 through a flange 57 using a bolt.

[80] In the current embodiment, at least one of a vibration preventing unit B, a tapping shank retard means 60, and an oil recycling means 70 may be further included.

[81] The vibration preventing unit B prevents vibration of the tapping shank 10 while the tapping shank 10 is rotated. The vibration preventing unit B is formed of rollers for three point suspending and cylinders rising and falling the rollers, as in a vibration preventing device disclosed in a nut tapping system (KR 10-0352458 (published on August 29, 2002) filed by the applicant of the present application.

[82] The tapping shank retard means 60 is spaced apart from the rear end of the open-

and-close panel 50 and is installed. The moving part 13 and the horizontal part 17 of the tapping shank 10 are located on the same line. The curve part 15 of the tapping shank 10 is placed in the groove part 43 of the tapping shank rotating body 40 and moves back-and- forth in a drive shaft direction according to operation of the pusher 93.

[83] The tapping shank retard means 60 includes a retard part 61, on which a fixing groove 62 is formed, a bearing 63, and a fixing plate 64. The retard part 61 is spaced apart from the rear end of the open-and-close panel 50 and includes the fixing groove 62 in which the rear end of the horizontal part 17 is placed when the tapping shank 10 moves back according to back-and-forth movement of the tapping shank 10. When the rear end of the tapping shank 10 (rear end of the horizontal part 17) is placed in the fixing groove 62, the retard part 61 rotates along with the tapping shank 10. The bearing 63 surrounds the outer circumferential surface of the retard part 61 and allows the retard part 61 to stably rotate. The fixing plate 64 is combined and fixed to the base body 90 to fix and support the bearing 63. Then, although the rear end of the horizontal part 17 is placed in the fixing groove 62 of the retard part 61 and the retard part 61 is rotated, the retard part 61 may stably rotate by the fixing plate 64 and the bearing 63.

[84] The oil recycling means 70 is used to reuse oil supplied for convenience of a nut tapping process. The oil recycling means 70 may include the first hopper 71, a second hopper 72, a chip separator 73, and the oil container 75, and may further include a chip collector 77.

[85] The first hopper 71 is formed at the lower side of the tap 11, in which nut tapping is performed. In the first hopper 71, chips generated during nut tapping and supplied oil are collected. The first hopper 71 is connected to the chip separator 73 and supplies the collected oil and chips.

[86] The chip separator 73 separates oil and chips supplied from the first hopper 71. The separated oil is collected in the oil container 75 and the separated chips are discharged to the chip collector 77.

[87] The oil container 75 contains oil for supplying oil to the tap 11, in which a nut tapping process is performed, for convenience of the process.

[88] The second hopper 72 is formed at the lower side of the tapping shank rotating means 20 in correspondence to the oil and chip discharge unit 44. In the second hopper 72, oil and chips discharged through the oil and chip discharge unit 44 according to the rotation of the tapping shank rotating means 20 are collected. The second hopper 72 is connected to any one of the hip separator 73 and the oil container 75.

[89] Hereinafter, a process of replacing the tapping shank 10 in the nut tapping apparatus and the operation of the nut tapping according to the current embodiment are described.

[90] FIG. 9 illustrates the tapping shank 10 being installed in the nut tapping apparatus of

FIG. 7 and FIG. 10 illustrates an operated state of the tapping shank 10 rotated in the nut tapping apparatus of FIG. 7. Referring to FIGS. 9 and 10, a process of replacing the tapping shank 10 is same as that of in the previous embodiment. However, the open- and-close panel 50 according to the current embodiment is combined to the rear end of the tapping shank rotating body 40 through the flange 57 using a bolt. The operation of the nut tapping according to the current embodiment is same as that of in the previous embodiment. However, since the vibration preventing unit B is further included in the current embodiment, vibration generated while the tapping shank 10 is rotated may be prevented.

[91] In addition, as described in the previous embodiment, the curve part 15 of the tapping shank 10 according to the current embodiment may move back- and- forth in a drive shaft direction in the groove part 43 of the tapping shank rotating body 40. Here, since the tapping shank 10 moves back-and-forth, the rear end of the horizontal part 17 may collide with the base body 90 and may be worn and thereby, the nuts N moved along the curve part 15 may collide with the inner wall of the groove part 43. Thus, the exterior of the nuts N may be damaged.

[92] Accordingly, since the tapping shank retard means 60 is further included in the current embodiment, the nuts N moved along the curve part 15 are prevented from colliding with the inner wall of the groove part 43 and thus, the exterior of the nuts N is prevented from being damaged. In addition, according to back-and-forth movement of the tapping shank 10, the retard part 61, in which the rear end of the horizontal part 17 is placed, is rotated. Thus, the rear end of the horizontal part 17 is prevented from being worn and the tapping shank 10 is stably supported so that there is an excellent effect on preventing vibration generated by rotation of the tapping shank 10.

[93] In addition, oil is supplied to the part of the nuts N, where nut tapping is accomplished, from the oil container 75 through a pump (not shown). While oil supplied through the pump (not shown) passes through the art of the nuts N, where nut tapping is accomplished, oil and chips are mixed and are collected in the first hopper 71. Oil and chips collected in the first hopper 71 pass through the chip separator 73 and are separated from each other. The separated oil is again collected in the oil container 75 and the separated chips are discharged to the chip collector 77. Then, oil including the chips discharged through the oil and chip discharge unit 44 of the tapping shank rotating means 20 is collected in the second hopper 72. Oil and chips collected in the second hopper 72 pass through the chip separator 73 and are separated from each other.

[94] In general, particles of the chips included in oil discharged through the oil and chip discharge unit 44 are very small so that oil collected in the second hopper 72 may be

directly collected in the oil contain 75 without passing through the chip separator 73.

[95] In other words, a separate oil hydrator (not shown) is used conventionally to separate oil and chips and thus, a process is further added. Also, in the conventional method, frictional heat from the nuts N and the tap 11 is cooled and oil sticks to the nuts N so that oil and chips are hardly separated from the nuts N using a simple hydrating process.

[96] However, in the present invention, rotation force of the tapping shank 10, which rotates at high-speed, is used to separate oil and chips from the nuts N before the frictional heat from the nuts N and the tap 11 is cooled. Also, since the nuts N are discharged in a free fall type, it is convenient to separate oil and chips from the nuts N.

[97] Hereinafter, the tapping shank 10 and the nut tapping apparatus using the tapping shank 10 according to the current embodiment will be described more fully with reference to the accompanying drawings.

[98] FIG. 11 is a perspective view of the tapping shank rotating means 20 in the nut tapping apparatus according to another embodiment of the present invention. Referring to FIG. 11, the tapping shank 10 according to the current embodiment includes the tap 11, the moving part 13, the curve part 15, and the horizontal part 17 and is same as the tapping shank 10 described in the previous embodiments. The nut tapping apparatus according to the current embodiment is same as the nut tapping apparatus according to the previous embodiments.

[99] However, the tapping shank rotating means 20 according to the current embodiment includes the sleeve 30, the tapping shank rotating body 40, and the open-and-close panel 50 as a single body. As described in the previous embodiments, the sleeve 30 includes the moving part 13 placed therein, and the tapping shank rotating body 40 and the open-and-close panel 50 formed as a single body is divided into two in a drive shaft direction, thereby forming a pair of tapping shank fixing bodies 40a.

[100] In the tapping shank fixing bodies 40a, the second moving path 42, the groove part 43, the oil and chip discharge unit 44, and the nut discharge unit 51 are respectively divided into two and are formed to be symmetrical each other. Here, the combined second moving path 42 is connected to the first moving path 31.

[101] In this case, the sleeve 30 and the tapping shank fixing bodies 40a may be combined through the fixing hole using a bolt as described in the first embodiment. Also, any one of the tapping shank fixing bodies 40a is combined to the sleeve 30 as a single body or a pair of tapping shank fixing bodies 40a may be combined and fixed to each other through a separate fixing hole using a bolt.

[102] While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing

from the spirit and scope of the present invention as defined by the following claims. Industrial Applicability

[103] In the nut tapping apparatus according to the present invention, nut tapping is accomplished to the inner circumferential surface of the nut by continuously pushing the nuts to be fixed to the tapping shank while the tapping shank, in which the tap is formed at the front end thereof, is rotated.

[104] In the nut tapping apparatus according to the present invention, while the nuts, to which nut tapping is accomplished, move along the tapping shank, oil and chips can be separated from the nuts by the centrifugal force, and the nuts can be discharged from the tapping shank without being scattered.