JPH042404A - Boring head - Google Patents

Abstract

PURPOSE:To accurately adjust a radial projecting amount of a cutter over a wide extent with a simple structure by advancing gradually a slide rod in an eccentric longitudinal hole provided in a cylindrical body through the rotation of a split rotary ring to project a cutter from an inclined hole. CONSTITUTION:When a cutter setting screw 32 and ring fixing screw 28 are loosened to rotate a split rotary ring 22, a slide rod 11 advances or retreats by the threading engagement of a female thread 24 of the rotary ring 22 with a partial male thread 14 of a slide body 11. In the advance of the slide rod, a holding surface 17 urges the rear end face of a cutter 18 to move the cutter 18 outward and tighten the cutter setting screw 32 and ring fixing screw 28, and in the retreat the cutter 18 is pushed into the inside. An inclined hole 7 making an angle of 45 deg. to the axis equalizes the axial movement amount of the slide rod 11 and the radial projecting amount of the cutter 18 to each other so that the projecting amount can be adjusted over a wide extent with fine adjustment for use in both roughing-down and finishing in common.

Description

[Detailed description of the invention] (Industrial application field) This invention relates to improvements in boring heads.

In particular, the present invention relates to a boring head that has a simple structure and can adjust the amount of radial protrusion of the cutter over a wide range and with high precision.

(Prior Art) A polling knife is a rod-shaped tool with a cutter at the tip, and the base is attached to a rotational drive spindle and rotates therewith.

As the blade rotates, a circular hole is drilled into the surface of the workpiece. The diameter of this hole is determined by the distance between the axis of the boring head and the tip of the cutting tool.

Therefore, in order to drill holes of different diameters, it is necessary to change the amount of protrusion of the cutter in the radial direction. The amount of protrusion must be determined with high accuracy.

To do this, for example, move the boring head in two directions.
A mechanism is used in which the blade is divided into parts and the front part to which the cutter is attached is moved in a direction perpendicular to the axis relative to the rear part fixed to the spindle.

For example, Utility Model Application No. 60-48904 (S60.4.6
) is one in which the head is divided into two parts and the two parts are joined by a diametrical dovetail groove. By relatively moving the head portion along the dovetail groove, the radial protrusion amount of the cutter is changed. A bearing mechanism is provided on each surface of the dovetail groove in order to relatively move the blade attachment portion and the machine tool attachment portion along the dovetail groove.

Also, a large bolt parallel to the groove is provided in the diametrical direction, and the bolt is screwed into a female screw hole drilled in the base of the blade attachment part. By twisting the bolt, the entire blade mounting part can be moved in the radial direction.

In Japanese Patent Publication No. 62-53282, the amount of radial protrusion of the cutter gradually changes while the head is rotating. This head is also divided into two parts, one on the blade side and one on the machine tool mounting side. Both have concave portions and convex portions formed in the diametrical direction, and are combined by combining the concave and convex portions. Since the sides of the unevenness are parallel to the diametrical direction, both can be relatively displaced in the diametrical direction.

For relative displacement, a female threaded hole is bored in the diametrical direction on the side of the blade that is equipped with a thick bolt in the diametrical direction, and the bolt is screwed into this hole. Both ends of the bolt are rotatably supported by the machine tool mounting side. When the bolt is rotated, the blade side moves in the radial direction. In reality, radial movement is converted into axial movement by a cam surface, which is then converted back into radial movement by another cam surface. This is for deceleration.

This device is highly accurate as it allows the blade to protrude in the radial direction in extremely small amounts.

The amount of protrusion can be defined with an accuracy of about 1/10100O.

(Problems to be Solved by the Invention) In order to subtly change the amount of radial protrusion of the cutter, the conventional device 1 moves one part of the head that is integrated with the cutter relative to the other part. ing. For this reason, the head is divided into two parts, and a convex and concave dovetail groove structure is formed in the diametrical direction. In addition to such a sliding mechanism, a large number of bearing mechanisms and springs are required to change the sliding mechanism.

The structure is extremely complex. The disadvantage is that the manufacturing cost is high due to its complexity.

Furthermore, since the head is divided into two parts along a plane perpendicular to the axis and these parts are eccentrically moved to move relative to each other, the eccentric stroke is narrow. Since the circular axes of the same diameter are shifted in the radial direction, the range in which the connection of these cylindrical parts is stable is 115 or less of the diameter. In many cases, the adjustable range is on the order of a few degrees.

Another drawback is that the head is divided into two parts, which weakens the strength of the head shank. Although the concave and convex portions of the dovetail groove are used for connection, there is a risk that the groove may be worn out or deformed.

In view of these difficulties, it is an object of the present invention to provide a boring head that has a simple structure and that can accurately adjust the amount of radial protrusion over a wide range.

(Means for Solving the Problems) The boring head of the present invention has a cylindrical shape, and has an eccentric vertical hole bored in the axial direction leaving an end portion, and a boring head that is continuous with the terminal end of the eccentric vertical hole. A diagonal entry is made at an angle of 45 degrees with respect to the axial direction into which a cutter is to be inserted, into a head body having a first flange portion and a second flange portion with an enlarged diameter in the center, and an eccentric vertical hole in the head body. a sliding rod that is slidable in the axial direction but is inserted in a non-rotatable manner and has a threaded portion (m) carved on the circumferential surface of at least an eccentric portion of the intermediate portion; the first flange portion of the head body; a split rotary ring provided to surround the circumferential surface between the two flanges and having a female thread carved on the inner circumferential surface to be screwed into the partial male screw; One end of the sliding rod holds down the rear end of the blade, and by turning the split rotating ring, the sliding rod is moved in the axial direction, causing the blade to protrude. I decided to decide the amount,
It is characterized by

(Function) Insert a suitable blade into the oblique entry of the head body. Move the cutter while turning the split rotary ring so that the protrusion amount in the radial direction of the cutter becomes an appropriate value.

First, the blade is moved backward in the opposite direction using the sliding rod in the eccentric vertical hole. In this state, the rear end of the cutter is brought into contact with one end of the sliding rod. When you turn the chive sub-rotation ring, the partial male screw and
The partial male screw moves back and forth at the threading point of the female thread. In this way, the sliding rod is advanced little by little toward the knife. As the sliding rod pushes the blade, the blade gradually protrudes from the diagonal entry point.

The amount of radial protrusion is equal to the amount of advancement of the sliding rod. When the appropriate amount of protrusion is reached, the blade is fixed in this state. Also fix the leek sub rotation ring.

Attach the rear part of the head body to the spindle of the machine tool. When the machine tool is driven and the spindle is lowered, the rotating blade drills a round hole in the workpiece.

Even when the cutter is attached to a machine tool, the protrusion amount of the cutter can be changed.

(Example) The polling method of the present invention will be explained with reference to drawings showing an example. FIG. 1 is a front view of a boring head according to an embodiment, and FIG. 2 is a cross-sectional view of a fir tree.

Cross sections of each part in FIG. 2 are shown in FIGS. 3 to 6.

The head main body 1 is an integrated shaft body, and has a cutting tool attachment part 2 at the tip and a machine tool attachment part 3 at the rear end. A first flange 4 and a second flange 5 having a larger diameter are formed in the middle with an interval between them.

The collar portion 4.5 is eccentric to one side with respect to the blade attachment portion 2 and the machine tool attachment portion 3. Blade mounting part 2 and machine tool mounting part 3
are concentric in this example, but the cores may be different depending on the case.

In the longitudinal direction of the head body 1, a long eccentric vertical hole 6 is bored at an eccentric position except for a slight length at the tip. An oblique entry 7 is bored at the tip of the eccentric vertical hole 6, making an angle of 135° with the axis of the eccentric vertical hole 6. Further, a female hole 8 is bored from the end surface of the head body 1 so as to be substantially orthogonal to the oblique entry 7.

A female hole 9 is bored in the radial direction on the circumferential surface of the blade attachment part 2 of the head body l.

A # threaded hole 10 is provided in the second flange portion 5 near the machine tool attachment portion 3 in the axial direction.

A cylindrical sliding rod 11 is inserted into the eccentric vertical hole 6 of the head body 1. The sliding rod 11 is a member having a circular cross section for the most part, but has a partial male mosquito 14 sandwiched between cutouts 12, 13 in the middle.

The partial male mosquito 14 has a very important role in the boring head of the present invention. This is a partial screw in a double sense. One is that it is partial in the longitudinal direction. The sliding rod 11 must slide smoothly and without rattling inside the eccentric vertical hole 6 having a circular cross section. Therefore, the side peripheral surface 15 excluding the partial male mosquito 14 needs to be a highly accurate cylindrical surface. The partial male mosquito 14 has such cylindrical surfaces on both sides. In this sense it is longitudinally partial.

The other is that it is partial in the circumferential direction.

Although a male thread is carved, this only needs to be done on one half of the surface in the eccentric direction. It may be narrower than a half plane (center angle is 180°) and may be about a quarter plane (center angle is 90°).

There are notches 12.13 on both sides of the partial male mosquito I4 because
This is so that this part will not get in the way when carving the male butterfly.

A guide vertical groove 16 is cut in the longitudinal direction on the surface opposite to the surface on which the partial male mosquito 14 is provided.

The tip of the sliding rod 11 serves as a holding surface 17, and the end surface is hardened. This becomes a surface that contacts and positions the rear end surface of the blade IBO. The top surface 19 on the opposite side of the sliding rod 11 has no role, but the top surface 19 is kept in the eccentric vertical hole 6 even when the cutter 18 is retreated to the innermost position.

The middle between the first flange 4 and the second flange 5 of the head body 1 is a circumferential surface 20 having a smaller diameter than the flange. Tsuba 4.
5 is eccentric with respect to other parts of the head body l,
The eccentric vertical hole 6 is eccentric in the opposite direction to the axis of the head body l. Therefore, a portion of the circumferential surface 20 communicates with the eccentric vertical hole 6. This partial opening 2
1 is a curved rectangular window formed in the eccentric direction of the eccentric vertical hole 6.

When the aforementioned sliding rod 11 is inserted into the eccentric vertical hole 6, there is a partial opening 21 in a part of the circumferential surface 20, through which a part of the partial male mosquito 14 is exposed.

A chive sub-rotation ring 22 is rotatably attached to the circumferential surface 20 sandwiched between the first flange 4 and the second flange 5. The chive sub-rotating ring 22 is a combination of two semicircular rings 23. A female thread 24 is cut into the inner peripheral surface of the semicircular ring 23. This female thread 24 is threadedly engaged with the partial male thread 14 of the sliding rod 11. Even though they are screwed together, they are not all the way around, but only a part of them is circumscribed or inscribed.

This female thread 24 circumscribes the circumferential surface 20 of the head main body l except for the portion where it is screwed into the male portions g and 14.

The semi-circular ring 23 (FIG. 5) is connected by two ring set screws 25 to form one complete ring. Since the inner diameter of the rotating ring 22 is smaller than the outer diameter of the flange 4.5, it is split into pieces and attached to the middle of the flange.

The outer circumferential surface of the split rotary ring 22 is divided into sections in the axial direction. A scale 26 (FIG. 1) is engraved on one side. The rotation angle of the rotary ring 22 can be accurately determined from this scale 26.

A knurling 27 is cut in the other part of the chive-splitting rotary ring 22. The leek sub-rotating ring 22 can rotate freely, but in order to fix it, tighten the ring fixing screw 28 screwed into the female hole 10 of the second collar 5 (Fig. 2).
.

When the ring fixing screw 28 is loosened and the leek sub-rotating ring is turned, the sliding Ill moves back and forth in the axial direction because the female thread 24 and the partial male thread 14 are screwed together.

The sliding rod 11 must not rotate. For this purpose, the tip of the guide screw 29 screwed into the female hole 9 bored in the radial direction of the head body l is inserted into the vertical groove 16 of the sliding rod 11. Since the relationship is as shown in FIGS. 2 and 4, the guide screw 29 prevents the vertical groove 16 from rotating.

However, the linear movement of the slide rod 11 in the longitudinal direction is not hindered.

A blade 18 is inserted into the diagonal hole 7 at the tip of the blade mounting portion 2 of the head body 1. The cutter 18 can move obliquely within the oblique hole 7 forming an oblique angle of 45°. The knife 18 can be fixed by a knife set screw 31 which is screwed into a female hole 30 bored on the side of the head.

A diagonal female screw hole 8 is diagonally bored in the bottom surface of the head body 1, into which a knife set screw 32 is screwed.

The operation will be explained in the above configuration.

To adjust the amount of protrusion (radial direction) of the blade 18, loosen the blade set screws 31, 32 (FIGS. 2 and 4). Loosen the ring fixing screw 28. And - split rotating ring 2
Rotate 2. Then, the sliding rod 11 moves forward or backward due to the screw engagement between the female hole 10 of the rotating ring 22 and the partial male hole 14 of the head body 1. When moving forward, the holding surface 17 of the sliding rod 11 presses the rear end surface of the cutter 18.

Then, the knife moves outward for a day. Knife lock screw 3 again
1. Tighten 32. Also, tighten the ring fixing screw 28.

When the sliding rod 11 is retracted, the cutter 18 must be pushed inward. In this case, there is a risk of an error in the amount of protrusion due to differences in pushing force, but in reality there is little need to continuously retract the blade, so this is not a big problem.

When increasing the diameter of the hole little by little, the cutting edge is made to protrude little by little. In this case, the sliding rod 11 pushes the rear end of the cutting tool 18, allowing for highly accurate adjustment.

Since the diagonal hole 7 is at an angle of 45° to the axis, the sliding rod 1
The amount of movement of the blade in the axial direction and the amount of protrusion of the cutter in the radial direction are equal.

Partial male mosquitoes 14 each time the leek-splitting rotary ring 22 rotates once.
The sliding rod 11 advances by a distance equal to the pinch P. For this reason, the blade also expands in diameter by P in the radial direction. The scale 26 is marked with dimensions that are further subdivided by 1 pitch P.

By moving the cutter 18 with respect to the head body 1 in this manner, the amount of protrusion of the cutter in the radial direction can be adjusted. The adjustable range is wide, and the diameter can be adjusted in the range of 30 mm to 90 am.

In other words, it is possible to have an adjustable range of at least 15 mm in terms of radius. This range is determined by the extent of the intersection of the oblique entry 7 and the eccentric vertical hole 6. This is the length when the rear end of the blade crosses the eccentric vertical hole 6 and passes through it diagonally, so if the inner diameter of the eccentric vertical hole 6 is E, the blade is pushed out by the sliding rod 11. The length F of the range that can be reached is F = E (1). Also, the movable range S in the radial direction of the cutter is S = F
(2). In the end, S=E. For example, if the diameter of the sliding rod is 1511Ill+, the radial movable range of the blade is 15 mm, which is 30 m in diameter.
It is m.

If the radial movable range S is to be expanded, the diameters of the sliding rod and the eccentric vertical hole 6 must be increased.

In the case of conventional boring heads, roughing and finishing are performed using separate tools, and finishing boring heads have a cutting tool with a radial movement of 1 to 3 II.
! It was about 11.

In comparison, the device of the present invention can move 15 to 45II111. It can be adjusted over a wide range. Moreover, minute adjustments can be made by rotating the split rotary ring 22. Adjustment of about I/loo++on is easy.

Therefore, the boring head of the present invention has the following features:
It can be used for both finishing purposes.

Furthermore, the cutter and the head main body 1 are not integrally connected, but by changing the cutter, not only drilling but also chamfering can be performed continuously. This also has the excellent advantage of improving work efficiency.

In this example, a guide vertical groove 16 and a guide screw 29 are used to inhibit rotation of the sliding rod.

The anti-rotation mechanism is not limited to this. For example, the eccentric vertical hole 6 may not be a circular hole, but a hole with a corner portion, and the sliding rod may also have a shape corresponding to this. For example, the hole may have a square or hexagonal cross section, and the sliding rod may also have a square or hexagonal column. The sliding rod 11 only needs to have an arcuate cross section at the portion of the partial male mosquito 14.

This boring head has a remarkable feature in that the sliding rod that moves inside the head body is aligned with the head body.

Why does it have to be eccentric? There are two main reasons for this.

(1) One reason is to completely grip the head body of the cutter. The tip of the sliding rod pushes out the knife, but the knife is gripped by the part of the navel body beyond this point. Since the sliding rod is eccentric in the direction opposite to the direction in which the blade comes out, the blade gripping area can be widened.

(2) The other reason is to maintain the rigidity of the hend body. If the eccentricity of the sliding rod were to be less than this, the inner diameter of the leek sub-rotating ring 22 would have to be smaller. As a result, the head body becomes narrower at this portion, making it more likely to break at this portion. To prevent this, the sliding rod should be eccentric to the opposite side of the knife as much as possible. In addition, the leek sub-rotating ring is made to be as eccentric as possible to the side opposite to the sliding rod.

(Effects of the invention) (1) The structure is simple. Conventional mechanisms often effect radial movement of the cutter by dividing the head itself into two parts and moving them relative to each other in a radial direction. To do this, concave and convex dovetail grooves must be cut to connect the two head parts. Also,
For relative movement, many parts such as cams, screws, bolts, and bearings must be assembled. The mechanism of the present invention is
Consists of only the head body, chive sub-rotating ring, and sliding rod.
It has an extremely simple structure.

(2) The radial adjustment range is extremely wide. This allows the blade to be moved in the radial direction by the diameter of the sliding rod.

Depending on the diameter of the hole, the adjustable range is at least 30m
If the sliding rod is made thicker, it can be extended to more than this (~90m+). The conventional mechanism is 1m for finishing purposes.
Only about three cabinets can be adjusted.

(3) Since the head body is integrated, it is extremely robust.

The head body is processed into a single rod by cutting.

It is not divided into two parts in the middle. In the conventional type, the head body was divided into two parts in order to move the blade in the radial direction. As a result, the connecting portion becomes weak and not sturdy.

(4) The center of rotation does not change and the balance is extremely good.

The sliding rod only moves in the axial direction. If the rotation is set so that it passes through the center of gravity of the head body, the center of rotation will not move away from the center of gravity even if the protruding object of the blade changes, so it will always rotate in a well-balanced manner.

If the head section, which is quite heavy, is moved in the radial direction as in conventional mechanisms, the center of gravity shifts from the center of rotation.

This will cause a considerable amount of misalignment in the rotation of the head. For this reason, the adjustment range of the blade protrusion amount is narrowly limited in the conventional mechanism.

(5) It is also possible to finely adjust the amount of protrusion of the blade. For this reason, conventionally, holes were drilled in two steps: roughing and finishing, but with the apparatus of the present invention, both steps can be performed with one tool.

(6) In addition to drilling holes, by replacing only the cutter, counterboring and chamfering can be performed with the same head.

[Brief explanation of the drawing]

Fig. 1 is a side view of a boring head according to an embodiment of the present invention, Fig. 2 is a vertical sectional side view of the same, Fig. 3 is a sectional view taken along the line ■-■ in Fig. FIG. 5 is a cross-sectional view taken along line V--V in FIG. 2, and FIG. 6 is a cross-sectional view taken along line ■-V in FIG. DESCRIPTION OF SYMBOLS 1... Head main body, 2... Blade attachment part, 3... Machine tool attachment part, 4... First collar part, 5... Second collar part,
6... Eccentric vertical hole, 7... Oblique type, 8... Oblique female screw hole,
9... Female mosquito hole, 10... Female mosquito hole, 11... Sliding rod, 12.13... Notch, 14... Partial male mosquito, 1
5... Side peripheral surface, 16... Vertical groove, 17... Pressing surface,
18...Cuttle, 19...Top surface, 20...Circumferential surface,
21... Partial opening, 22... Chive split rotating ring,
23...Semicircular ring, 24...Female thread, 25...Ring set screw, 26...Scale, 27...Knurl. Figure 3 Figure 4

Claims (1)

[Claims] A diagonal hole having a substantially cylindrical shape, in which an eccentric vertical hole is drilled with an eccentric end left in the axial direction, and a cutting tool is inserted continuously into the terminal end of the eccentric vertical hole, making an angle of 45 degrees with respect to the axial direction. a head body having a first flange portion and a second flange portion with an enlarged diameter in the center, and a head body that is slidably axially but non-rotatably inserted into the eccentric vertical hole of the head body; A sliding rod having a partial male thread carved on a partial circumferential surface in an eccentric direction of the intermediate portion and a circumferential surface between the first flange and the second flange of the head body. It consists of a two-split rotary ring with a female thread carved into the inner circumferential surface that engages with the partial male thread, and a cutter set screw that fixes the cutter inserted into the oblique hole. A boring head characterized in that one end of the blade is pressed against the rear end of the blade, and by turning a split rotary ring, the sliding rod is moved in the axial direction to determine the amount of protrusion of the blade.