JPH0743109U - Drill grinding machine for thinning - Google Patents

Abstract

(57) [Summary] [Purpose] A thinning drill grinder capable of easily performing thinning together with drill grinding is put on the market. [Structure] In a drill grinder for grinding a drill cutting edge, a polishing grindstone is a flat grindstone, and a mounting table for the grinding grindstone is a combination of a horizontal slider on the lower side and a vertical slider on the upper side of the apparatus body. The former slides in the left-right direction and the latter slides in the front-rear direction.In addition, a grinding wheel mount equipped with a motor for rotating the grinding wheel is turned upward in a semi-circular shape at the front edge of the vertical slider. In addition to movably supporting the shaft, the shaft fulcrum is located on the center line of the drill.First, the grinding wheel is ground without rotating the grinding wheel in a semi-circular arc, and then the grinding wheel is moved above the cutting edge. It is characterized in that thinning is performed by rotating a semicircular arc toward the edge side.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a drill grinding machine for thinning, which facilitates thinning. (Prior Art) In the drilling work, generally about half of the thrust of cutting resistance is concentrated on the chisel edge of the drill tip. Therefore, as shown in FIGS. 1A and 1B, thinning F ₁ , F on the chisel edge E of the drill tip is used. _{When 2} is applied, the chip discharge at the tip is improved, the thrust is reduced, and the life of the drill is gradually extended. In the drawing, A ₁ and A ₂ are groove portions B ₁ and B ₂ of a drill, respectively. By the way, the conventional thinning for this purpose is performed by using a thinning device prepared separately from the drill grinding, so that the work is troublesome and expensive. (Problems to be Solved by the Invention) In view of the above points, the present invention provides a commercially available thinning drill grinder capable of performing thinning together with drill grinding. In the present invention, the device disclosed in Japanese Patent Publication No. 59-43263 previously proposed is used for grinding a drill blade. The present invention is an improvement of such a device so that the thinning of the chisel edge can be easily performed within a desired range, and the drill blade grinding and the thinning work can be efficiently performed by one device. Is. (Means for Solving the Problem) In a drill grinder that grinds a drill cutting edge, a polishing grindstone is a flat grindstone, and a mounting table for the grindstone is a horizontal slider on the lower side of the apparatus main body and a vertical slider on the upper side. In the combination of the sliders, the former slides in the left and right direction and the latter slides in the front and rear direction.In addition, the grindstone stand equipped with a motor for rotating the grinding grindstone is directed upward at the front edge of the vertical slider. And the pivot point is located on the center line of the drill.First, the grinding edge of the drill is ground without rotating the grinding wheel, and then the grinding wheel. Is characterized in that the thinning is performed by rotating the tool into a semicircular arc toward the upper edge of the drill cutting edge. (Example) FIG. 2 is a perspective view of the entire apparatus, FIG. 3 is a front view seen from the C side of FIG. 1, FIG. 4 is a side view seen from the D side, and FIG. FIG. 6 is an exploded perspective view showing a sliding mechanism related to the mounting table, and FIG. 6 is an operation explanatory view. Reference numeral 1 is an apparatus main body, 2 is a conical tip angle setting pedestal rotatably installed at one side position on the main body 1 within an arbitrary angle range in a horizontal direction, and is composed of upper and lower divided frames 2a and 2b, In this case, the upper frame 2a is configured to be swingable with respect to the lower frame 2b within a preset range of eccentricity. 3 is a spindle case, 4 is a chuck, 5 is a drill gripped by the chuck, 6 is a spindle rotation handle, and these are placed on the upper frame 2a. One rotation of the spindle rotation handle 6 causes the upper frame 2a to rotate. Shakes twice with respect to the lower frame 2b within a preset eccentricity range, whereby the drill cutting edges (B ₁ , B ₂ ) in contact with the grinding wheel are ground. The specific structure for this is as described in Japanese Patent Publication No. 59-43263. Reference numeral 7 denotes a base for holding the polishing grindstone at a constant height at the other side position of the apparatus main body 2. On the base, the grinding grindstone G is laterally (a) (b) or through a horizontal slider 8 and a vertical slider 9. It is slidable in the front-back (c) and (d) directions. Specifically, as shown in FIG. 5, a dovetail groove projection 10 is provided on the base 7, and a dovetail groove 11 that engages with the dovetail groove 8 is formed on the lateral slider 8 so that both are fitted and engaged. A rack 12 is attached to the front surface of the gantry, and a rack gear 13 that meshes with the rack 12 is attached to the front surface of the lateral slider 8. In this case, 14 is a bearing portion, 15 is a supporting shaft thereof, and 16 is the rack gear. A lateral lever 8 is a lever attached to a support shaft 15 for rotating by operating a handle, and the lateral slider 8 slides in the left and right (a) and (b) directions when the lever 16 swings. In addition, a dovetail groove projection 17 for engaging with the vertical slider 9 is provided on the upper surface of the horizontal slider 8, and the projection 17 is formed at a constant rising angle (approximately 10 ° to 20 °) toward the front surface portion. In addition, in parallel with this, a female screw 19 is engraved inward in the rear center of the protrusion 17 in a certain length range. On the other hand, the vertical slider 9 is provided with bearing portions 20a and 20b for supporting a grindstone mount, which will be described later, on the front surface thereof, and a dovetail groove 21 for engaging with the dovetail groove projection 17 is bored on the lower inner surface. The rear surface of the horizontal slider 8 is fixed to the bracket plate 25 which rotatably supports the grip 24 having the male screw 23 at the front end in the lengthwise direction by using the set screw 26. The male screw 23 of the grip 24 and the female screw 19 provided on the dovetail protrusion 17 are screwed together when they are fitted into and engaged with the dovetail protrusion 17. The vertical slider 9 is slid in the front-rear (c) (d) direction by the rotation in the (h) direction. Reference numeral 27 is a grindstone mount, which is provided with bearing portions 28a and 28b on both sides of the lower surface, and is rotatably supported by a bearing shaft 29 in a engaged state with the bearing portion of the vertical slider 9 and has an upper surface. A motor 30 having a grinding wheel G attached to a drive shaft is integrally mounted on the section. Reference numeral 31 is a lever provided on the grindstone base 27, and the lever 31 is held by hand and pulled toward the rear surface side of the vertical slider 9 during the thinning work described below. Is semi-circularly rotated about the support shaft 29 in the direction of arrow (i). (Refer to FIG. 6) In the drawing, 32 is a grindstone cover 33 and 34 is a stopper screw screw rod for restricting the tilted position in the front and rear of the grindstone mount 27. Next, the operation will be described. In the present invention, in the initial grinding of the cutting edge of the drill 5 (B ₁ and B _{2 in} FIG. ₁ ), the drill 5 is held on the chuck 4 as shown in FIG. The _position where the rotational axis of the grindstone G _{is lower than the} drill center line 0-O _{1 , that is, θ is about −10 ° in the illustrated example. Further, the conical tip angle setting base 2 is slightly loosened from the clamp handle K and rotated appropriately according to the conical tip angle so that the grinding surface (B 1} or B ₂ ) of the _{drill blade does not} come into contact with the grinding wheel G. Then, the clamp handle K is tightened and fixed in that state. Then, the motor 30 is driven to rotate the grinding wheel G in the direction of the arrow (N), and the main spindle rotating handle 6 is appropriately rotated to grind the drill cutting edge surfaces (B ₁ , B ₂ ). The state in which grinding is performed in accordance with the rotation of the spindle rotation handle 6 is as described in Japanese Patent Publication No. 59-45263, and the grinding wheel G during the work is held by the grip 24 by hand and rotated appropriately. By moving it, the vertical slider 9 is slid in the rearward direction (C) so that a good contact state can always be obtained. The thinning of the ground drill cutting edge is subsequently performed by the device. Specifically, the clamp K is loosened, and the tip of the drill blade and the grinding surface of the grinding wheel G are conical. The tip K setting base 2 is rotated to tighten the clamp K, and the lever 16 is held by hand and appropriately swung to slide the lateral slider 8 in the left and right directions (a) and (b), thereby polishing the grinding wheel. Place one edge of G (m, see FIG. 2) at a desired setting position P (see FIG. 1A) on the chisel edge E, and then drive the motor 30 to rotate the grinding wheel to As shown in FIG. 6, the lever 31 is held by hand and is rotated in a semi-circular direction in the direction of the arrow (r), whereby the polishing grindstone G moves to the upper side of the drill cutting edge surface and moves from the point P set at the above position to Chisel edge part is thinning F And than the those ₁ is performed the thinning F ₂ other halves in the same manner. (Effects of the device) The device of the present invention can perform grinding of the drill blade edge and thinning together with one drill grinder as described above, and it is not necessary to prepare a thinning device separately. In addition to being able to continuously perform the drill while it is held in the chuck, it is very efficient and excellent in workability and contributes to cost reduction.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a drill cutting edge portion, A is a front view, B is a side view, FIG. 2 is a perspective view of the entire apparatus, and FIG. 3 is C of FIG.
The front view seen from the side, FIG. 4 is the side view seen from the same D,
FIG. 5 is an exploded perspective view showing a sliding mechanism related to the mounting table of the polishing grindstone, and FIG. 6 is an operation explanatory view. DESCRIPTION OF SYMBOLS 1 ... Device main body 2 ... Tip angle setting base 3 ... Spindle case 4 ... Chuck 5 ... Spindle rotation handle 8 ... Horizontal slider 9 ... Vertical slider 16 ... Lever 27 ... Grindstone mount 30 ... Motor 31 ... Lever G ... Polishing wheel

Claims (1)

[Claims for utility model registration] (1) In a drill grinder that grinds a drill cutting edge,
The polishing grindstone is a flat grindstone, and the mounting table of the grinding grindstone is configured as a combination of a horizontal slider on the lower side and a vertical slider on the upper side of the apparatus main body, the former slides in the left-right direction and the latter slides in the front-rear direction. In addition to the above, a grinding wheel mount equipped with a motor for rotating the grinding wheel is pivotally supported upward at the front edge of the vertical slider so that it can be rotated in a semi-circular arc, and the shaft fulcrum is on the center line of the drill. It is configured so that thinning is performed by first grinding the drill cutting edge without rotating the grinding wheel half arc, then rotating the grinding wheel half arc to the upper edge side of the drill cutting edge. A drill grinder for thinning that is characterized by