JP2008114314A - Drill polishing machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a drill polishing machine to polish a drill by sequentially carrying out polishing processes by using a plurality of jigs arranged in the periphery of a grinding wheel, capable of increasing freedom of mounting the jigs, improving work efficiency and increasing the polishing processes. <P>SOLUTION: This drill polishing machine consists of a driving device 13, the grinding wheel 25 rotationally driven by the driving device 13, a base to support the driving device 13 and the plurality of jigs for each of the polishing processes mounted on the base, and is constituted such that a rotation axis of the grinding wheel 25 is of a vertical spindle vertical to the base, a stage 15 in parallel with a rotating surface of the grinding wheel 25 is integrally provided with the base 12 between the base and the grinding wheel 25 and the plurality of jigs such as a drill setting jig 32, etc. are mounted on the stage 15. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a drill polishing machine, and more particularly, drill polishing suitable for polishing a drill used when removing a welded portion without drilling a hole in a base material by drilling a spot welded portion of a vehicle body panel. Related to the machine.

  The present invention relates to a grinding machine for a drill used for removing a spot weld, a driving device, a grindstone that is rotationally driven by the driving device, a base that supports the driving device, and an outer surface of the grindstone on the base. Conventionally, a drill polishing machine that includes a plurality of jigs arranged for each polishing process and that sequentially inserts drills to be polished into the plurality of jigs to execute the polishing process is known. (Patent Document 1, Patent Document 2).

The conventional drill grinder is a horizontal shaft type in which a drive shaft of a drive device installed on a base and a rotation shaft of a grindstone connected thereto are parallel to the base so that the grindstone rotates in a vertical plane. It has become. Further, as a jig provided for executing the above polishing step, a drill setting jig ("Drill adjustment piece 2" in Patent Document 1, hereinafter the same in parentheses), a cutting edge polishing jig (drill polishing table 3). ), A thinning jig (drill thinning table 4) is fixed to the base, and a drill setting process, a cutting edge polishing process, and a thinning process can be sequentially performed using each jig. The drill to be polished is set in a predetermined positioning state with respect to the drill holder in the drill setting step, and the subsequent polishing step is executed while maintaining the set state.
Republished patent WO99 / 28082 Japanese Utility Model Publication No. 7-15247

  In the conventional drill polishing machine described above, the cutting edge polishing step and the thinning step are both polishing steps by applying the tip of the drill to the outer peripheral surface of the grindstone. It is necessary to install the thinning jig around the grindstone.

  However, the conventional drill grinder is of the horizontal axis type as described above, and the grindstone rotates toward the operator in the vertical plane with respect to the horizontally installed base, so that the jigs are fixed. The space on the base suitable for is limited to a position close to the outer peripheral surface of the grindstone and close to the operator. Therefore, the planar arrangement of the jigs must be extremely close and tight. In addition, the shape of the thinning jig is particularly complicated because the tip of each jig must be structured so as to face the outer surface of the grindstone while maintaining a certain distance along the outer circumference of the grindstone. There is also a problem that becomes.

  There is some space in the part of the base part opposite to the worker's position that is close to the outer peripheral surface of the grindstone, but it is away from the worker, so even if a jig is installed in such a space There is a problem of reducing the performance.

  As described above, in the conventional case, the jig mounting position is limited. Therefore, the drill setting jig is arranged on the base away from the grindstone, and two kinds of jigs are arranged around the grindstone (cutting blades). It is not possible to attach other jigs (for example, chamfering jigs) around the grindstone, or even if it can, it will be an obstacle to workability. there were.

  Therefore, in the present invention, the first problem is to increase the number of jigs arranged around the grindstone and increase the polishing process by increasing the degree of freedom of jig attachment around the grindstone. To do.

  On the other hand, when polishing by bringing the tip of the drill into contact with the outer peripheral surface of the grindstone, polishing by inclining so as to have an advance angle with respect to the rotation direction is called “reverse polishing”, and conversely in the rotation direction. In the case of the above-mentioned Patent Documents 1 and 2, in which the slanting with a delay angle with respect to the polishing is referred to as “forward polishing”, the reverse polishing is performed in the other general polishings. Yes. This is because reverse polishing has a higher polishing efficiency than forward polishing, and it is easy to take a structure that receives the torque at the time of polishing received from a grindstone by a support stand installed at the operator's hand.

  However, in the case of reverse direction polishing, a large polishing resistance acts on the polishing surface of the grindstone, which causes a problem that the polishing surface melts due to high-temperature heat generation. In addition, there is a problem that the polished surface is rough and polishing powder is scattered on the operator side.

  Therefore, in this invention, the amount of polishing in the polishing of the drill is relatively small, the friction during polishing is relatively small, so the forward polishing is employed, avoiding high temperature heat generation, and a smooth polished surface is obtained, A second problem is to provide a drill grinder that can easily treat abrasive powder.

  Further, in order to prevent the outer peripheral edge of the flank from becoming sharp and easily chipped by polishing the cutting edge, chamfering is generally performed on the outer flank of the flank after polishing, but the above-mentioned patent document relates to chamfering. There is no description. The height of the outer peripheral edge of the cutting edge flank of the drill is changed in the direction of the centerline of the drill when viewed in the direction of rotation, and when the chamfer is applied to the so-called margin part of the outer peripheral edge. The margin cutting edge has a disadvantage because the clearance angle is lost, so it is necessary to chamfer to avoid this. I have to be.

  Therefore, in the present invention, the third problem is to simplify the structure of the chamfering jig used when performing the chamfering process, and to form a required flank in the margin portion. And

  In addition, in the conventional case, the drill holder consists of two parts, the drill setting process is complicated, and the swing structure for thinning polishing in the thinning jig is necessary, so the structure is complicated. Another problem is to simplify the structure.

  In order to solve the first problem, the present invention provides a drive device 13, a grindstone 25 that is rotationally driven by the drive device 13, a base 12 that supports the drive device 13, and the base 12. In a drill grinder comprising a plurality of attached jigs and capable of sequentially performing a drill polishing process using the plurality of jigs, the rotating shaft 14 of the grindstone 25 is perpendicular to the base 12. A stage 15 parallel to the rotating surface of the grindstone 25 is provided integrally with the base 12 between the base 12 and the grindstone 25, and the plurality of jigs are attached to the stage 15. The configuration.

  According to the said structure, since the rotating surface of the grindstone 25 is horizontal and the stage 15 parallel to the rotating surface is provided close to the grindstone 25, the conventional surface 15 is maintained while maintaining a required interval in the circumferential direction. More jigs can be installed in a highly flexible arrangement.

  Examples of the jig include a cutting blade polishing jig 33, a thinning jig 34, and a chamfering jig 35 disposed on the stage 15. The drill setting jig 32 for setting the drill 45 to be polished on the drill holder 39 can be attached to any one of the stage 15, the base 12, and the base cover 18.

  In order to solve the second problem, in the present invention, the grinding wheel center line in the plan view of the center line of each positioning ring of the cutting blade polishing jig 33, the thinning jig 34, and the chamfering jig 45 is used. A configuration in which the inclination angle has a delay angle (−φ) with respect to the rotation direction R of the grindstone 25, and the drill 45 inserted in each jig contacts the grindstone 25 and is subjected to forward polishing. did.

Furthermore, in order to solve the third problem, in the present invention, as the chamfering jig 35, a jig base 83 fixed to the stage 15 and a positioning ring 84 provided on the jig base 83 are provided. The positioning member 85 has a restriction hole 86 having a size adapted to the diameter of the drill 45, and the center line of the positioning ring 84 is located with respect to the chamfered polishing portion 48 of the grindstone 25. has a predetermined chamfer angle alpha ₁₀ Te, the distance from the restriction hole 86 until the chamfered abrasive portion 48 is set to a predetermined distance n, the predetermined distance to the center line a ₃ around the outer end surface of the positioning ring 84 A holding range regulating recess 88 is provided, and the chamfering range ch of the outer peripheral edge of the flank 53 of the drill 45 is provided in the vicinity of the cutting edge 52 ′ from the torsion groove 54 side by the regulation recess 88. It is restricted to a range extending, and end point b of the chamfer ranges ch was constructed in on the vertical center line R _4.

  As described above, according to the present invention, since the rotating shaft 14 of the grindstone 25 is a vertical axis type, the stage 15 integrated with the base 12 other than the base 12 can be installed in parallel with the rotating surface of the grindstone 25. The stage 15 can be used, and more jigs can be installed around the grindstone 25 with a high degree of freedom than in the conventional case. As a result, the workability of drill polishing can be improved, and there is an effect that fine polishing can be performed by increasing the number of polishing steps.

  Further, since the drill 45 is subjected to forward polishing by the grindstone 25, abnormal heat generation of the polished surface is prevented, and it is easy to collect the polishing powder, and the finished surface of the polishing is smooth. .

Further, chamfering jig employs a configuration in which the distance from the restriction hole 86 to the chamfer grinding portion 48 is set to a constant value n, also by grinding range restricting recess 88 for regulating the rotation around the center line A ₃ by terminating point b of the chamfer ranges ch has adopted the configuration that on the vertical center line R _4, construction of the chamfering jig is simplified, also 'flank 53' cutting edge 52 of the margin portion is formed Therefore, the sharpness of the cutting blade 52 ′ is not impaired.

  In addition, there are effects that the drill holder 39 is composed of a single sleeve-like component, that the thinning shaft 34 does not require a movable part, and that the structure is simple.

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

<Description of configuration>
As shown in FIGS. 1 and 2, in the drill grinder of the embodiment, a drive device 13 (a motor in the case of illustration) vertically rotates its rotating shaft 14 on a base 12 installed horizontally on a work table 11. It is installed in the vertical axis type toward In addition, a stage 15 penetrating the bearing portion of the rotating shaft 14 is disposed on the upper end surface of the driving device, and the base 12 and the stage 15 are connected to a plurality of connecting bolts 16 penetrating the casing of the driving device 13. The drive device 13 is clamped and fixed by the nut 17 or the like from above and below. Further, a base cover 18 surrounding the base 12 and a range of a little lower half of the drive device 13 is attached to the boss portion 20 by a fixing screw 20 ′ screwed from the base 12 side. A power supply wiring, a power supply capacitor, and the like are accommodated in the base cover 18, and a power switch 19 is attached to the outer peripheral surface thereof.

  The means for integrating the stage 15 with respect to the base 12 is not limited to the above-described configuration, and the configuration in which the stage 15 is directly fixed to the upper end surface of the casing of the driving device 13 fixed to the base 12 and the illustrated base cover 18 are extended upward. In addition, it is possible to adopt a configuration in which the upper end surface is formed so as to cover the upper end surface of the driving device 13 and the upper end surface is used as the stage 15.

  A receiving plate 22 is fitted to the step portion 21 of the rotating shaft 14, and a centering ring 23 is fitted to the rotating shaft 14 on the receiving plate 22. A nut 24 is screwed into a screw portion of the rotary shaft 14 protruding upward from the centering ring 23, and the grindstone receiving plate 22 is fastened and fixed to the stepped portion 21 together with the centering ring 23. The grindstone 25 is fitted around the centering ring 23 and fixed to the receiving plate 22 by screws 26. Around the insertion hole 29, a conical seal cover 31 covering the range up to the stepped portion 21 is attached (see FIG. 2).

  Since the grindstone 25 is driven by the rotary shaft 14 provided in the vertical direction, this type is called a vertical axis type. In the illustrated case, the driving device 13 is also of a vertical axis type, but the rotation axis of the driving device 13 is configured as a horizontal axis type parallel to the base 12, and the rotation axis of the grindstone 25 is connected to the rotation axis via a bevel gear mechanism. May be a vertical axis type provided vertically.

  As shown in FIG. 3, the planar shapes of the base 12 and the base cover 18 are notched at right angles to a center line Y1 drawn on the surface of the base 12 through the center O of the base 12 on the back side of the entire machine. It has an oval shape having a D-shaped cut portion 27. An insertion hole 28 of the driving device 13 is formed in the center portion of the base cover 18. The D-shaped cut portion 27 is the rear end side of the machine, and the opposite surface is the front (front face) of the machine. On the front side, the power switch 19 is attached at a position offset to the right side by about 20 degrees from the center line Y1.

The stage 15 has a disk shape, and is only an angle θ ₁ (about 20 ° to 30 °) with the center O of the base 12 and the base cover 18 as a rotation center with respect to the center line Y1 (refer to the X1-Y1 coordinates). A center line Y2 (see X2-Y2 coordinates) is provided at a position rotated leftward in plan view, and the center O ′ is arranged at a position eccentric to the right front by a predetermined amount on the center line Y2. Since the stage 15 is eccentric to the right front with respect to the base 12 and the base cover 18, a large crescent-shaped mounting space 30 is formed at a position offset to the right front.

  A drill setting jig 32, a thinning jig 34, a cutting edge polishing jig 33, and a chamfering jig 35 are arranged on the mounting space 30 in order from the left side of the front surface along the outer peripheral surface of the grindstone 25. The center line Y <b> 1 exists between the drill setting jig 32 and the thinning jig 34. The cutting edge polishing jig 33 is arranged on the center line Y2, and the chamfering jig 35 is installed at a position of about 90 °. Further, a polishing powder dropping hole 36 is provided between the cutting edge polishing jig 33 and the chamfering jig 35, and the polishing powder guide plate 37 (see FIG. 1) is formed along the side edge of the polishing powder dropping hole 36 on the chamfering jig 35 side. ) Is provided. A polishing powder case 38 is detachably attached to the lower surface of the polishing powder dropping hole 36.

  A grindstone cover 41 is provided that surrounds a range of about a half circumference on the rear side of the grindstone 25 from the outer peripheral edge of the stage 15 outside the polishing dust hole 36 to the outside of the chamfering jig 35. The height of the peripheral wall portion of the grindstone cover 41 is set to be slightly higher than the upper surface of the grindstone 25, and a top plate portion that covers the upper surface of the grindstone 25 is provided on the peripheral wall portion. The portion of the grindstone cover 41 facing the machine front of the peripheral wall portion and the top plate portion is opened, and a portion of the grindstone 25 is exposed to the opened portion, and the jigs 32 to 35 are exposed to the exposed portion. opposite. A transparent dustproof cover 43 is attached on the top plate portion of the grindstone cover 41 via a spacer 42.

  A holder holding pin 44 for holding a drill holder 39, which will be described later, is drilled in a space generated in a plane on the left rear base cover 18 generated by attaching the stage 15 eccentrically to the right front as described above. The required number of holders 39 are provided in a protruding manner.

  The drill setting jig 32 may be attached in the vicinity of the holding pin 44 on the upper surface of the base cover 18.

The grindstone 25 is a CBN electrodeposited grindstone, and its cross-sectional shape is shown in FIG. The grindstone 25 includes a cutting edge polishing portion 46 formed over an outer peripheral surface 46a and a chamfered portion 46b at a lower peripheral edge thereof, a thinning polishing portion 47 formed at an upper end flange portion 47a of the outer peripheral surface 46a, A chamfering polishing portion 48 formed on the upper end surface of the grindstone 25 is provided. The outer peripheral surface 46a is lowered inclined to minute angle theta ₂ Daketsuba portion 47a side with respect to the rotary shaft 14. The minute angle θ ₂ is an inclination angle for forming a cutting edge angle α ₁ (see FIG. 5A) of the cutting edge 52 as described later. Further, the chamfered portion 46b becomes a chisel polishing portion. The flange portion 47a on which the thinning polishing portion 47 is formed is an arcuate surface having an appropriate radius.

  With respect to the rotation direction R of the grindstone 25 (see FIG. 4B), the drill 45 to be polished is pressed against the polishing surface with a predetermined inclination angle using jigs 33 to 35 described later. In this case, as shown in the figure, when a center line xy perpendicular to the center of the grindstone 25 in the plan view of the grindstone 25 is drawn to the polishing portion that is in contact with the drill 45, the center line x is used as a reference with respect to the rotation direction R. Polishing with an inclination so as to have a lead angle (+ φ) is called “reverse polishing”, and conversely has a delay angle (−φ, including −φ = 0 °) with respect to the rotation direction R. Such tilting and polishing is referred to as “forward polishing”. In the present invention, forward polishing is selected as the drill polishing.

Next, details of the drill 45 to be polished will be described with reference to FIGS. The drill 45 in this case has a tip shape suitable for drilling a thin plate such as when removing a spot welded portion of a vehicle body panel, that is, a large tip cutting edge angle α ₁ exceeding 180 degrees (see FIG. 5A). It has a so-called candle-shaped tip shape in which a chisel 51 is formed at the holding center.

Tip shape before polishing, arose attrition or chipping by the use in the intended candle-shaped, the tip cutting angle alpha ₁ tip shape is not candle form is a variety, such as those of general-purpose 118 degrees.

  5 (b) to 5 (d) show the shape of a polishing intermediate product obtained by subjecting the drill 45 to cutting edge polishing, and FIGS. 6 (a) to 6 (e) show polishing with chisel polishing and chamfering polishing in addition to this. Indicates the finished state. As shown in FIG. 5 (b), cutting edges 52 and 52 are formed on both sides of the chisel 51 by cutting edge polishing, and a flank 53 is located behind the cutting direction of each cutting edge 52 (see arrow a). Is formed.

  By applying chisel polishing and chamfering polishing to the intermediate polished product, the twisted groove 54 of the other cutting blade 52 passes through the side of the chisel 51 of each cutting blade 52 as shown in FIG. A thinning 55 is formed in the portion that moves to (1). Thinning refers to a polishing operation in which the thickness of the chisel 51 is scraped off within a range that does not impair the strength of the drill in order to increase drilling efficiency, or a portion that has been subjected to such a polishing operation. In the present invention, “thinning 55” means a portion subjected to a thinning polishing operation. Further, a chamfer 56 (see FIG. 6D) is formed on the outer peripheral edge of the flank 53 so as to reach a part of the margin 57. A range from the chamfer 56 of the margin 57 to the cutting edge 52 'of the margin 57 is a flat flank 53'.

The flank 53 has a relief angle alpha ₂ relative to cutting edge 52 in the rear of the cutting edge 52 (see FIG. 6 (e)). Further, the cutting edge 52 ′ at the margin 57 also has a clearance angle α ₃ (see FIG. 6 (f)).

When the chamfered 56 subjected throughout the outer periphery of the flank 53 comprises a portion of the margin 57 'becomes relief angle alpha ₃ is zero, the cutting edge 52' cutting edge 52 of the portion of the margin 57 in the portion of Sharpness decreases. Therefore, in the present invention, 'as sufficient sharpness can be obtained even in the portion of the cutting edge 52' cutting edge 52 so as to form a clearance angle alpha ₃ in part of. The forming means will be described later.

  Next, the jigs 32 to 35 will be described.

  As shown in FIGS. 1 and 7, the drill setting jig 32 includes a jig base 61 fixed to the upper surface of the base cover 18 and a vertical support integrated with the outer peripheral surface of the jig base 61. The positioning ring 63 is supported by the arm 62. The positioning ring 63 is opened in the vertical direction and has an inner diameter that fits the above-described drill holder 39, and the drill holder 39 is removably inserted into the inner diameter surface thereof.

  A restriction pin 64 protrudes at one place on the upper surface of the positioning ring 63. A cylindrical adjustment piece 65 concentric with the positioning ring 63 is fitted to the center of the jig base 61 so as to be movable up and down. An adjustment screw hole 66 is provided in the portion of the stage 15 facing the adjustment piece 65, and the adjustment bolt 70 a is screwed from below the stage 15. A locking nut 70b is screwed onto the adjustment bolt 70a. A set screw 67 of the adjustment piece 65 is inserted from the side surface of the jig base 61. A cutting edge positioning protrusion 68 having a size capable of being fitted into the twist groove 54 at the tip of the drill 45 is provided on the upper end surface of the adjustment piece 65.

  The height H of the upper surface of the positioning ring 63 with respect to the upper surface of the adjustment piece 65 is the polished height h when the cutting blade polishing step is performed using the cutting blade polishing jig 33 (see FIG. 9). Is set by operating the adjusting bolt 70a in advance to a size obtained by adding a required polishing allowance δ to the above.

  The drill holder 39 has a sleeve shape, and as shown in FIG. 7D, a knurling 40 is provided on the outer peripheral surface of the upper end, and a positioning pin 69 protruding radially is provided on the outer peripheral surface. The outer diameter and length of the drill holder 39 are constant regardless of the size of the drill 45, but the inner diameter B varies depending on the diameter of the drill 45 (see B ').

The height of the positioning pins 69 is a position shifted by the center line A ₃ direction difference a which differ by the size of the diameter of the drill 45 (see FIG. 12 (b)) in the chamfering step described below. The drill holder 39 is provided with a set screw 71 for the drill 45.

  The drill setting process for setting the drill 45 to the drill holder 39 using the drill setting jig 32 will be described later. Here, for the understanding of the configuration of other jigs 33, 34, and 35 described below. The process will be described in the necessary range.

  The drill set process is the first executed process and a preparation for polishing. First, a drill holder 39 that matches the size of the drill 45 to be polished is selected, and only the drill holder 39 is inserted into the positioning ring 63 from above, and the right side with the positioning pin 69 resting on the upper surface of the positioning ring 63. Rotate (see arrow b in FIG. 7B) and hit against the regulation pin 64. Next, the drill 45 is inserted into the hole of the drill holder 39 from above, the tip of the drill 45 is brought into contact with the upper surface of the adjustment piece 65, the drill 45 is further rotated clockwise, and one of the cutting blades 52 is engaged with the cutting blade positioning projection 68. (Refer to (c) in the figure). In this state, the set screw 71 is tightened and the drill 45 is set in the drill holder 39.

  When the drill setting step is completed, the second cutting edge polishing is performed by using the cutting edge polishing jig 33 that is next to the thinning jig 34 that is installed on the right side of the drill setting jig 32 and that is next to the thinning jig 34. The process is executed. The reason why the cutting blade polishing jig 33 used in the second process is installed on the right side of the thinning jig 34 used third is that the work in the cutting blade polishing process is more complicated than the work in the thinning process. This is because it is desirable from the viewpoint of workability to install the cutting blade polishing jig 33 in a portion where the operator's right hand is easily freed at a position where the working position is relatively to the right. Of course, there may be a pattern arranged in the order of processes, such as the cutting blade polishing jig 33 second from the left and the third thinning jig 34 adjacent to the right.

As shown in FIGS. 8 and 9, the cutting blade polishing jig 33 has support arms 73 provided vertically on both sides of a jig base 72, and a positioning ring 74 is provided between the support arms 73. The center line A _{1 of} 74 (see FIG. 8, this center line A ₁ coincides with the center line of the drill 45 held by the positioning ring 74) is fixed by a horizontal screw shaft 75 so as to be adjustable in angle. The The center line A ₁ is inclined at an inclination angle α ₅ (around 5 ° in the case of illustration) that is a delay angle with respect to the center line R ₁ in a plan view of the grindstone 25, that is, forward polishing is performed. And is set so as to intersect with a predetermined position of the cutting edge polishing portion 46 of the grindstone 25. The inclination angle α ₅ is formed at an angle necessary for forming the tip cutting edge angle α ₁ (see FIG. 5).

Side view of the positioning ring 74 the slope of the center line A1 in (see Fig. 9 (a)), i.e., the inclination angle alpha ₆ relative to the plane of rotation of the grinding wheel 45 of the center line A1 (upper and lower surfaces in the mounting state) in the illustrated zero It is. This inclination angle α ₆ forms a clearance angle α ₂ (see FIG. 6 (e)) on the clearance surface 53 of the drill 45, but in the illustrated case, a small angle θ ₂ (see FIG. 4) is applied to the cutting edge polishing portion 46 of the grindstone 45. (See (a)) is given, thereby forming a clearance angle α ₂ (see FIG. 6 (e)). Conversely, the inclination angle theta ₂ is the case of zero inclination angle alpha ₆ is set to a predetermined size. The angles α ₅ and α ₆ are collectively referred to as a cutting edge polishing angle.

Further, two cutting edge range restricting recesses 76 are provided at the center symmetrical positions on the front surface of the positioning ring 74 (the surface opposite to the grindstone 25, that is, the surface on the operator side) (see FIG. 9B). The groove width in the circumferential direction of the regulating recess 76 is formed so as to have an angle range α ₇ necessary for grinding one cutting edge 52 of the drill 45 and its flank 53. Position of the regulating recess 76, both sides of the restriction wall 76a, the inclination with respect to the horizontal plane of the 76b is set to an angle beta ₁ and beta _2. The angles β ₁ and β ₂ are determined by the size of the angle α ₄ of the cutting edge 52 of the drill 45 with respect to the drill holder 39 described above, the cutting polishing start point, and the like.

In the case shown in the figure, in the state of FIG. 9B in which the positioning pin 69 of the drill holder 39 hits the left regulation wall 76a, the polishing start point of the cutting edge 52 and its flank 53 is a predetermined position of the cutting edge polishing section 46. The angle β ₁ is set so as to be in contact with. Angle beta ₂ of the right restriction wall 76b also polishing endpoint of the cutting edge 52 and its flank 53 is set so as to be in contact with the predetermined position of the cutting edge grinding unit 46.

Next, the thinning jig 34 will be described with reference to FIGS. Also in this case, the support arms 78 are provided vertically on both sides of the jig base 77, and the positioning ring 79 is interposed between the support arms 78 along the center line A ₂ of the positioning ring 79 (FIGS. 10A and 3). see, the center line a ₂ are angle adjustment secured by the horizontal direction of the screw shaft 81 perpendicular to coincide with the center line of the drill 45.). The center line A ₂ is inclined at an inclination angle α ₈ (around 60 ° in the case of illustration) that is a delay angle with respect to the center line R ₂ in a plan view of the grindstone 25, that is, forward polishing is performed. So as to be inclined.

Further, the inclination of the center line A _{2 in} a side view (see FIG. 10B), that is, the inclination angle α ₉ of the center line A ₂ with respect to the rotating surface of the grindstone 25 is set to about 20 °. The inclination angle of the thinning 55 is set by the inclination angles α ₈ and α ₉ as described later. The inclination angles α ₈ and α ₉ are collectively referred to as a thinning angle.

Extension of the center line A ₂ of the Earl portion of the flange tip of the grindstone 25, that intersect the predetermined position of the thinning polishing section 47, a predetermined thinning angle is set.

A radial thinning restricting recess 82 formed on the front end surface of the positioning ring 79 is formed to have a width equal to the diameter of the positioning pin 69 of the drill holder 39, and the positioning pin 69 is fitted without any backlash in the rotational direction. The In consideration of the thinning workability, the position of the restriction recess 82 is determined so as to be at an intermediate position between the left and right support arms 78 and 78. In a state in which the positioning pin 69 of the drill holder 39 is fitted in the restriction recess 82 (see FIG. 11), the angle α ₄ (FIG. 7B) is set so that the tip of the drill 45 comes into contact with the grindstone 25 with a sinning angle. )) Is set.

Further, the distance from the bottom of the thinning restricting recess 82 to the thinning polishing portion 47 of the grindstone 25 is set to the thinning finish height m (see FIG. 10B). In FIG. 10B, m ₁ represents the size of the thinning allowance.

  Next, the installed chamfering jig 35 will be described with reference to FIGS. 12 to 15 with the cutting blade polishing jig 33 and the polishing powder dropping hole 36 adjacent to the right side of the thinning jig 34 interposed therebetween.

  The chamfering jig 35 includes a jig base 83 fixed to the stage 15, a positioning ring 84 provided on the jig base, and a positioning member 85. The positioning member 85 has an L-shaped angle shape, and its base portion 85a is sandwiched between the jig base 83 and the positioning ring 84, and the bent portion 85b at the distal end thereof extends from the positioning ring 84 toward the center line A3. Arranged at a predetermined distance D. The bent portion 85b is formed with a restriction hole 86 that allows the tip of the drill 45 to be inserted and prevents the drill holder 39 from being inserted.

The angle between the center line _{A 3} of the positioning ring 84 in a plan view of the grinding wheel 25 (see FIG. 13 (a)) is consistent zero, i.e. the center line _{R 3.} Further, set in a side view (see FIG. 12 (a)), the plane of rotation of the grinding wheel 25 of the center line _{A 3} predetermined chamfer angle chamfer angle alpha ₁₀ is against (chamfered polishing section 48) (typically 45 °) .

A chamfering range restricting recess 88 larger than the diameter of the positioning pin 69 of the holder 39 is provided on the outer end surface of the positioning ring 84. The restricting recess 88 restricts the circumferential chamfering range of the positioning pin 69. The restriction range is determined by the opening angle α ₁₁ of the restriction recess 88, and this angle is set to a size that covers almost the entire outer peripheral edge of the flank 53 of the drill 45. Further, in the state of FIG. 13B in which the positioning pin 69 is in contact with the polishing start point of the restriction recess 88 (right end when viewed from the front), the cutting blade 52 of the drill 45 is in a substantially horizontal chamfering start state. As described above, the angle α ₄ (see FIG. 7B) is set.

Moreover, the restriction hole 86 of the positioning member 85 on the center line A _3, the distance to the chamfer polishing unit 48 (see FIG. 12 (b)) is set to a constant value n. This n is set to a constant size regardless of the diameter of the drill 45. However, the size of the diameter of the drill 45, for chamfering finishing position difference in the centerline A ₃ direction position a (the see FIG. 12 (b)) is present, the positioning pins regardless of the diameter of the drill 45 In order to maintain the length from 69 to the tip of the drill 45 at the finished height h, the position of the positioning pin 69 is shifted in the direction of the center line A _{3 by} the difference a according to the diameter of the drill 45. It is necessary to use a drill holder 39 (see FIG. 7D). In FIG. 12C, n ₁ represents a chamfering allowance.

On the other hand, as shown in FIG. 14A, the outer peripheral edge of the flank 53 is a range from the point a at the end of the twisted groove 54 side to the point c at the cutting edge 52 side, but a margin close to the point c. A chamfering end point b is defined within a range 57, and a chamfering range ch is defined from point a to point b. The opening angle α ₁₁ (see FIG. 13B) of the restricting recess 88 is set to a size that allows the drill 45 to rotate from the point a to the point b together with the drill holder 39, and the point b is in contact with the chamfered polishing portion 48. , i.e., rotation of the drill holder 39 is stopped at the point where the point b is reached on the vertical center line R _4. By stopping the rotation at the point b, the outer peripheral edge between the points b and c is polished by the horizontal chamfering polishing portion 48 while the drill 45 is stationary, so that the polishing portion becomes a flat surface and is cut. A clearance surface 53 ′ having a clearance angle α ₃ (see FIG. 6F) with respect to the blade 52 ′ is formed.

<Description of action>
The drill grinder of the embodiment is configured as described above, and the operation thereof will be described next.

(Drill setting process)
A drill holder 39 suitable for the size of the drill 45 to be polished is selected (see FIG. 7), extracted from the holding pin 44, and the drill holder 39 is inserted from above the positioning ring 63 of the drill setting jig 32 (see FIG. 7). 7 (a)). With the positioning pin 69 of the drill holder 39 placed on the upper end surface of the positioning ring 63, the drill holder 39 is rotated to the right (see arrow b in FIG. 7B) in plan view, and the positioning pin 69 is engaged with the restriction pin 64. Combine. Next, the drill 45 is inserted from above the drill holder 39, the tip thereof is applied to the upper surface of the adjustment piece 65, the drill 45 is further rotated as appropriate, and one of the cutting blades 52 is engaged with the cutting blade positioning protrusion 68. (See FIG. 7C). In this state, the set screw 71 is tightened and the drill 45 is set in the drill holder 39.

In the set state, the height H (= h + δ) from the positioning pin 69 of the drill holder 39 to the tip of the drill 45 is set, and the cutting blade when viewed from the positioning pin 69 in the rotation direction of the drill 45 52 the angle alpha ₄ is set for.

(Cutting edge polishing process)
While driving the grindstone 25 to rotate counterclockwise (see arrow R in FIG. 8), the operator holds the drill holder 39 in the set state and inserts it into the positioning ring 74 of the cutting blade polishing jig 33. and (I see FIGS. 8 and 9), further reciprocally swung about the center line a ₁ in the range where the positioning pins 69 a drill holder 39 is restricted by the polishing range limiting groove 76. As a result, the drill 45 is polished in the forward direction so that one of the cutting edges 52 and the flank 53 have a predetermined tip cutting edge angle α ₁ and clearance angle α ₂ at the cutting edge polishing portion 46 of the grindstone 25. At the same time, one side of the chisel 51 is polished near the center of the flank 53 by the chamfered portion 46 b of the cutting edge polishing portion 46.

  When a predetermined polishing allowance δ (see FIG. 9A) is polished and a feeling that the positioning pin 69 is in contact with the bottom of the restriction recess 76 is obtained, the polishing is finished and the drill 45 is extracted together with the drill holder 39. Next, the drill holder 39 is rotated 180.degree. Around its center line, and this is inserted again into the positioning ring 74, and the positioning pin 69 is inserted into the other polishing range restricting recess 76 at the center symmetrical position. Similarly, the other cutting edge 52, the flank 53 and the other surface of the chisel 51 are polished. FIGS. 5B to 5C show the intermediate polished product thus polished.

  Since the polishing powder generated in the polishing process is forward polishing, it scatters in the rotational direction of the grindstone 25 opposite to the operator's position, is guided by the polishing powder guide plate 37, and passes through the polishing powder drop hole 36. Fall into. Further, in the above polishing, the polishing torque of the grindstone 25 acting on the tip of the drill 45 is received by the cutting blade polishing jig 33. In this case, the polishing torque is lower than that in the reverse direction polishing. There is no fear of abnormal heat generation on the polished surface, and the finished surface is smooth.

(Thinning process)
After the cutting blade polishing process is completed as described above, the holder 39 is extracted from the positioning ring 74 and inserted into the positioning ring 79 of the thinning jig 34 shown in FIGS. It fits into the thinning restricting recess 82. In this state, there is a clearance of polishing allowance m ₁ (see FIG. 10B) due to thinning between the positioning pin 69 and the bottom of the restricting recess 82.

When an operator applies force in the pushing direction while holding the drill holder 39, one side surface of the chisel 51 is pressed against the thinning polishing portion 47 of the grindstone 25, and thinning having a predetermined thinning angle by forward polishing. 55 is applied (see FIG. 6), and if it is felt that the projection 69 has reached the bottom surface of the restricting recess 82, the drill holder 39 is extracted together with the drill 45. Next, after rotating 180 ° around the center line A ₂ , it is inserted into the positioning ring 79 again for polishing, and the other thinning 55 is applied. In this case, the amount of abrasive powder is smaller than that in the previous step, but is also collected in the abrasive powder case 38.

  Even if the thinning 55 is applied, the polishing finish height h finished in the previous step does not change.

(Chamfering process)
After finishing the thinning process, the drill holder 39 is extracted from the positioning ring 79 and inserted into the positioning ring 84 of the chamfering jig 35 shown in FIGS. 12 and 13, and the positioning pin 69 is inserted into the chamfering range regulating recess 88. Insert. The outer peripheral edge of the cutting edge 52 of the drill 45 is chamfered and polished on the grindstone 25 at a position where the tip surface of the drill holder 39 is separated from the surface of the restriction hole 86 of the positioning member 85 by the chamfering margin n ₁ (see FIG. 12C). Approach part 48. At this time, the positioning pin 69 does not come into contact with the bottom surface until the separation step is finished from the bottom surface of the defining recess 88.

When the operator reciprocatingly swung in the left-right direction holder 39 about the center line A ₃ within the restriction recessed portion 88 by gripping the holder 39, the chamfered range point b from point a of the outer peripheral edge of the flank 53 A chamfer 56 is applied to ch (see FIG. 14A). However, since the a point side is located farther from the grindstone 25 than the b point side (retracted from the drill tip), the chamfer 56 is not formed in the vicinity of the a point, and the chamfer 56 is gradually formed as the point b is approached. The Since the rotation of the drill 45 is restricted at the point b, the chamfering polishing section 48 polishes the space between the point b and the point c of the drill 45 which is stationary with respect to the grindstone 25 and escapes to the cutting edge 52 ′. A flank 53 ′ having an angle α ₂ (see FIG. 6 (f)) is formed.

When sensation n ₁ by the progress of the chamfering abrasive of the tip of the drill holder 39 becomes zero is in contact with the portion of the restriction hole 86 is obtained, the drill holder 39 drawn with a drill 45, 180 ° around the center line A ₃ After the rotation, it is inserted again into the positioning ring 84 and chamfered and polished, and a chamfer 56 is applied to the chamfering range ch between the other cutting edge 52 and the outer peripheral edge of the flank 53.

  When the diameter of the drill 45 is different, the drill finish height h can be finished in any case by using the drill holder 39 in which the inner diameter adapted to the drill 45 and the position of the positioning pin 69 are different.

Incidentally, in order to chamfer 56 is started from a point near the, as indicated by chamfering abrasive allowance n ₂ in FIG. 12 (c), the positioning member so that chamfering grinding allowance is relatively large The position 85 is lowered (see the two-dot chain line in FIG. 12C). In this case, the constant value n is n ′.

Is a perspective view of the drill grinding machine of the embodiment Is a cross-sectional view of the above Is a plan view of the planar positional relationship between the base cover and the stage (A) The figure is a partially enlarged sectional view of the grindstone, (b) is an explanatory diagram showing the direction of rotation of the grindstone and the direction of the center line of the drill (A) The figure is a front view of the drill, (b) is a plan view of the drill blade tip of the polishing intermediate product, (c) is a front view of the figure (b), (d) is a side view of the figure (b) (A) is a plan view of a drill blade after polishing is completed, (b) is a front view of (a), (c) is a side view of (a), and (d) is (a). (E) is a cross-sectional view taken along line ee in FIG. (D), (f) is a cross-sectional view taken along line ff in (d), FIG. (A) The figure is sectional drawing of a drill setting process, (b) The figure is a top view of (a) figure, (c) The figure is sectional drawing of the cc line of (a) figure, (d) The figure is a drill holder Cross section of Is a plan view of the cutting edge polishing process (A) The figure is a vertical side view of the cutting edge polishing step, (b) is the left side view of (a), (c) is a partially enlarged view of (a). (A) is a plan view of the thinning process, (b) is a front view of (a). Is a left side view of the thinning process. (A) is a longitudinal sectional view of the chamfering process, (b) is a partially enlarged view of (a), and (c) is an explanatory view of the position of the positioning pin according to the drill diameter. (A) is a plan view of the chamfering process, (b) is a right side view of (a). (A) to (c) are explanatory diagrams of the chamfering process.

Explanation of symbols

11 Work table 12 Base 13 Driving device 14 Rotating shaft 15 Stage 16 Connecting bolt 17 Nut 18 Base cover 19 Power switch 20 Boss portion 20 'fixing screw 21 Step portion 22 Receiving plate 23 Centering ring 24 Nut 25 Grinding stone 26 Screw 27 D type Cut portion 28 Insertion hole 29 Insertion hole 30 Installation space 31 Seal cover 32 Drill set jig 33 Cutting blade polishing jig 34 Thinning jig 35 Chamfering jig 36 Abrasive dust drop hole 37 Abrasive powder guide plate 38 Abrasive powder case 39 Drill holder 40 Knurling 41 Grinding wheel cover 42 Spacer 43 Dust-proof cover 44 Holding pin 45 Drill 46 Cutting blade polishing part 46a Outer peripheral surface 46b Chamfering part 47 Thinning polishing part 47a Brim part 48 Chamfering polishing part 51 Chisel 52, 52 'Cutting edge 53, 53' Flank 54 Torsion groove 55 Thinning 56 surface 57 Margin 61 Jig base 62 Support arm 63 Positioning ring 64 Restriction pin 65 Adjustment piece 66 Adjustment screw hole 67 Set screw 68 Cutting blade positioning projection 69 Positioning pin 70a Adjustment bolt 70b Locking nut 71 Set screw 72 Jig base 73 Support Arm 74 Positioning ring 75 Screw shaft 76 Polishing range restriction recess 77 Jig base 78 Support arm 79 Positioning ring 81 Screw shaft 82 Thinning restriction recess 83 Jig base 84 Positioning ring 85 Positioning member 85a Base 85b Bending part 86 Restriction hole 88 Chamfering range Regulating recess

Claims (6)

  A driving device (13), a grindstone (25) that is rotationally driven by the driving device (13), a base (12) that supports the driving device (13), and a plurality of units mounted on the base (12) In the drill polishing machine, which is capable of sequentially executing a drill polishing process using the plurality of jigs, the rotating shaft (14) of the grindstone (25) is in relation to the base (12). A vertical axis type, and a stage (15) parallel to the rotating surface of the grindstone (25) is provided between the base (12) and the grindstone (25) integrally with the base (12), A drill polishing machine, wherein the plurality of jigs are attached to a stage (15).   The jig includes a cutting edge polishing jig (33), a thinning jig (34), and a chamfering jig (35), and a drill setting jig for setting a drill (45) to be polished on a drill holder (39). The drill grinder according to claim 1, wherein (32) is attached to any one of the stage (15), the base (12) and the base cover (18).   The cutting blade polishing jig (33), the thinning jig (34), and the chamfering jig (35) are arranged in a thinning jig (34) and a cutting blade polishing jig along the rotation direction of the grindstone (25). The drill polishing according to claim 2, wherein the order is (33) and the chamfering jig (35).   The grindstone (25) includes a cutting edge polishing portion (46) formed on a chamfered portion (46b) formed on an outer peripheral surface (46a) and a lower end peripheral portion thereof, and an upper end collar portion of the outer peripheral surface (46a). The thinning polishing part (47) formed in (47a) and the chamfering polishing part (48) formed in the upper end surface of the said grindstone (25) are characterized by the above-mentioned. Drill polishing machine. The drill holder (39), a drill setting jig (32), a cutting edge polishing jig (33), a thinning jig (34) and a chamfering jig (35) are configured as follows. The drill polishing apparatus according to 3 or 4.
a) The drill holder (39) has a sleeve shape through which the drill (45) passes, and a positioning pin (69) projecting radially on the outer diameter surface thereof, and a set screw (71) of the drill (45) ) Is provided.
b) The drill setting jig (32) includes a jig base (61) fixed to the stage (15), and a positioning ring (63) provided on the jig base (61) and opened up and down. Thus, the height H of the positioning ring upper end surface with respect to the jig base 61 is set to be larger than the polishing finish height h defined by c) below, and the regulation pin 64 protrudes from the upper end surface. The jig base (61) is provided with a cutting edge positioning protrusion (68) that engages with one cutting edge (52) of the drill (45) in the rotation direction of the drill (45). .
c) The cutting edge polishing jig (33) includes a jig base (72) fixed to the stage (15) and a positioning ring (74) provided on the jig base (72). positioning ring predetermined cutting grinding angle with respect to the cutting edge polishing portion (46) of the center line a ₁ is said grinding wheel (72) (25) (α 5, α 6) has, and the positioning ring (74) polishing range restricting recess having a predetermined distance in the center line a ₁ about the outer end face (76) is provided, wherein the center line a ₁ direction of the bottom surface and the cutting edge polishing portion of the regulation recess (76) (46 ) Is set to the polishing finish height h.
d) The thinning jig (34) is composed of a jig base (77) fixed to the stage (15) and a positioning ring (79) provided on the jig base (77). the drill to the outer end face of the ring predetermined thinning angle center line a ₂ Whereas thinning polishing section (47) of said grinding wheel (25) of (79) (alpha _8, alpha ₉₎ has, said positioning ring (79) holder thinning restricting recess compatible width to the diameter of the positioning pin (69) (82) is provided (39), wherein said center line a ₂ direction of the bottom surface of the restricting recess (82) thinning the polishing unit (47) The distance is set to the thinning finish height m.
e) The chamfering jig (35) includes a jig base (83) fixed to the stage (15), a positioning ring (84) provided on the jig base (83), and a positioning member (85). ) becomes from the said positioning member (85) is adapted to the diameter of the drill (45) on the center line a ₃ of the positioning ring (84) between said positioning ring (84) and said grinding wheel (25) have a size of the restriction hole (86), said center line a ₃ are having a predetermined chamfer angle (alpha ₁₀₎ with respect to the chamfered abrasive portion (48) of said grinding wheel (25), the restriction hole (86) the chamfered abrasive portion (48) distance to is set to a predetermined distance n, the polishing range restricting recess having a predetermined interval on the outer end surface to the center line a ₃ around the locating ring (84) (88) from Chamfering of the outer peripheral edge of the flank (53) of the drill (45) by the restriction recess (88). Range (ch) is restricted to a range extending from the spiral flute (54) side in the vicinity of the cutting edge (52 '), and configured to termination point b is on the vertical center line R ₄ chamfer range (ch). Center lines A ₁ , A ₂ , A _{3 of the} positioning rings (74), (79), (84) of the cutting blade polishing jig (33), the thinning jig (34), and the chamfering jig (35). The angle of inclination with respect to the center line (x) of the grindstone in plan view has a delay angle (−φ) with respect to the rotation direction R of the grindstone (25), and the drill (45) inserted into each jig is the grindstone. The drill grinder according to claim 5, wherein the grinder is forward-polished in contact with (25).

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