JP6268719B2 - brooch - Google Patents

Description

  The present invention relates to a broach in which a plurality of cutting blades are sequentially inserted into a prepared hole formed in a work material together with a broach main body to cut the prepared hole into a predetermined shape such as a helical internal gear shape. .

  Conventionally, as this type of broach, a plurality of cutting blades are arranged on the outer periphery of an axial broach main body, and the broach main body is placed in a pilot hole formed in the work material along the axial direction of the broach main body. It is known that the first hole is inserted into the first hole and the lower hole is cut into a predetermined shape by the plurality of cutting blades.

For example, the helical broach shown in the following Patent Document 1 is an assembly type in which the broach main body is composed of an axial main body portion having a large diameter portion and a small diameter portion adjacent in the axial direction, and a cylindrical shell portion. The shell portion is detachably attached to a small diameter portion located in the rear portion of the main body portion. In a state in which the main body portion and the shell portion are assembled, the plurality of cutting blades form a row over the outer periphery of the large diameter portion and the outer periphery of the shell portion in the main body portion.
In such an assembly type broach, if any of the cutting blade of the main body part and the cutting blade of the shell part is lost, it can be dealt with by replacing the main body part or the shell part in which the cutting edge is damaged, It is more economical than replacing the entire broach (i.e., compared to a one-piece broach).

  By the way, in the assembly type broach, when the main body part and the shell part rotate and move relative to each other around the axis line, the axis line becomes the boundary between the outer periphery of the main body part (large diameter part) and the outer periphery of the shell part. Since the row of cutting blades is shifted around the axis before and after the direction, it is necessary to regulate the relative rotation between the main body portion and the shell portion. Therefore, in Patent Document 1, a rectangular parallelepiped rib that protrudes rearward and extends in the radial direction is provided on the rear end surface of the large-diameter portion in the main body portion, while the front end surface of the shell portion has a diameter that is recessed rearward. A rectangular parallelepiped-shaped groove extending in the direction is provided, and the relative rotation between the main body portion and the shell portion is restricted by engaging the ribs and the grooves.

JP-A-10-202422

However, the conventional broach has the following problems.
That is, when the rib of the main body and the groove of the shell are engaged as described above, it is necessary to provide a clearance (gap) for engagement, and the main body and the shell are slightly separated by the clearance. Relative rotation caused the row of cutting edges to shift.

  Here, FIGS. 4 to 6 show a conventional broach 100. The broach 100 has a spiral shape that extends around the axis O as the row of cutting blades 101 moves rearward (right side in FIG. 4) in the tool feed direction D (that is, the row of cutting blades 101 is twisted by the lead L). A helical brooch. In FIG. 5, the rib 103 of the main body portion 102 extends in a direction perpendicular to the paper surface, and the groove 105 of the shell portion 104 also extends in a direction perpendicular to the paper surface (see FIG. 6 for the shape of the rib 103). The rib 103 and the groove 105 are engaged with each other, and a clearance for engagement is provided between the rib 103 and the groove 105 along the width direction of the rib 103 and the groove 105 (vertical direction in FIG. 5). Is provided.

  When cutting the prepared hole of the work material using the broach 100, the work material and the work material are fed while feeding the broach 100 in the tool feed direction D along the lead L of the cutting edge 101. The broach 100 is rotated relative to the axis O. In the course of cutting, when the cutting edge 101 of the shell portion 104 cuts into the prepared hole of the work material, the shell portion 104 receives a cutting load so that the body portion 102 is rotated about the axis O. It is rotated by the clearance.

  In the conventional broach 100, it is anticipated that the row of the cutting blades 101 will be shifted by this rotation, and the shell portion 104 is slightly movable toward the rear in the tool feed direction D with respect to the main body portion 102. Specifically, not only the clearance in the width direction (vertical direction in FIG. 5) of the rib 103 and the groove 105 between the rib 103 of the main body portion 102 and the groove 105 of the shell portion 104, but also the axis O direction ( A clearance toward the left and right direction in FIG. 5 is also provided.

  As a result, when the cutting edge 101 of the shell portion 104 cuts into the work material and receives a cutting load, the shell portion 104 moves toward the rear while rotating with respect to the main body portion 102 to move the lead L Therefore, the row of the cutting blades 101 is prevented from being displaced forward and backward in the direction of the axis O with respect to the connecting portion between the outer periphery of the main body portion 102 and the outer periphery of the shell portion 104.

However, it is not easy to stabilize the machining accuracy by such a complicated adjustment of the clearance, and the adjuster requires skill.
In addition, in a broach that is not a helical broach, that is, a broach in which the row of cutting edges extends parallel to the axial direction, the row of cutting edges must always move around the axis O when rotation occurs due to the clearance in the width direction. Since it was shifted, it was difficult to ensure processing accuracy.

  The present invention has been made in view of such circumstances, and regulates the relative rotation between the main body portion and the shell portion of the broach body, and the row of cutting blades is shifted before and after these connecting portions. An object of the present invention is to provide a broach capable of reliably preventing high-quality cutting and stably performing high-quality cutting.

In order to solve such problems and achieve the above object, the present invention proposes the following means.
That is, according to the present invention, a plurality of cutting blades are arranged on the outer periphery of an axial broach main body, and the broach main body is directed to a tool feed direction along the axial direction of the broach main body in a prepared hole formed in a work material. A broach for cutting the prepared hole into a predetermined shape with the plurality of cutting blades, wherein the broach body has a large diameter portion and a small diameter portion adjacent in the axial direction. And a cylindrical shell portion that is detachably attached to the small diameter portion, and the plurality of cutting blades are arranged over an outer periphery of the large diameter portion and an outer periphery of the shell portion, and the large diameter And the cutting edge of the shell portion are arranged in a spiral shape along a lead twisted around the axis toward the rear in the tool feed direction, and the shell portion side along the axial direction of the large diameter portion is arranged Facing end surface and the axis of the shell portion Of the end faces facing the large-diameter portion along the direction, one end face is formed with a rib projecting toward the other end face and extending in the radial direction perpendicular to the axis, and the other end face is A groove that is recessed in a direction away from the one end surface and extends in the radial direction is formed, and a pair of side surfaces facing the width direction of the rib on the one end surface are on the other end surface side along the axial direction. The pair of side surfaces facing the width direction of the groove on the other end surface are inclined so as to gradually move away from each other toward the one end surface side along the axial direction. , the rib and the groove, is brought into contact with the pair of side surfaces of each other, are fitted, said pair of side, Ri angle identical der mutually inclined relative to the axis, the large-diameter Department and front And the shell portion is fixed with no relative rotation.

  According to the broach of the present invention, the cylindrical shell portion is detachably attached to the small diameter portion of the main body portion that forms the shaft shape in the broach main body, and the end surface facing the shell portion side in the large diameter portion of the main body portion, Of the end surfaces facing the large diameter portion in the shell portion, a rib is formed on one end surface, and a groove is formed on the other end surface. The pair of side surfaces facing the width direction of the rib on one end surface are inclined so as to gradually reduce the distance from each other toward the other end surface side along the axial direction, and the width direction of the groove on the other end surface The pair of side surfaces that face each other are inclined so as to be gradually separated from each other toward one end surface along the axial direction.

That is, a pair of side surfaces (outer side surface) in the rib and a pair of side surfaces (inner side surface) in the groove are both tapered, and the rib and groove having these corresponding side surfaces are fitted to each other. It is like that. In this manner, the rib and the groove are taper-fitted, so that the clearance for engagement which has been conventionally required between the rib and the groove becomes unnecessary, and the relative rotation around the axis between the main body portion and the shell portion is eliminated. Will surely be regulated.
As a result, it is reliably prevented that the row of cutting blades is displaced in the axial direction before and after the connection portion between the outer periphery of the large diameter portion of the main body portion and the outer periphery of the shell portion. High quality cutting can be performed.

Further, since the clearance for the engagement is not necessary, the clearance in the axial direction is also unnecessary, so that the complicated adjustment work as in the prior art is not necessary, and according to the present invention, the workability of parts replacement and maintenance is improved. Greatly improved.
In addition, since relative rotation around the axis of the main body and the shell is reliably restricted, a remarkable effect can be obtained when the present invention is applied to a helical broach, as well as a broach that is not the helical broach, That is, even in a broach in which a row of cutting blades extends parallel to the axial direction, the machining accuracy is stably secured by applying the present invention.

  Moreover, the broach of this invention WHEREIN: The ring part which can press the said shell part toward the said large diameter part side along the said axial direction may be attached to the said small diameter part so that attachment or detachment is possible.

  In this case, the state in which the rib and the groove are taper-fitted is stably maintained, and the row of the cutting blades can be prevented more reliably.

  Moreover, the broach of this invention WHEREIN: The said ring part is good also as screwing so that it can advance / retreat to the said axial direction with respect to the said small diameter part.

  In this case, the rib and the groove can be surely taper-fitted by a simple operation of screwing the ring portion into the small diameter portion. That is, since the rib and the groove can be easily and reliably fitted, the accuracy of the cutting process can be stably increased.

  Further, in the broach of the present invention, the small diameter portion is formed with a stop groove extending along the axis, and the ring portion is provided with a pin member that advances and retracts so as to be engageable with the stop groove. It is good also as being done.

  In this case, since the relative movement between the ring portion and the small diameter portion is restricted by engaging the pin member with the stop groove, the ring portion stably presses the shell portion, and the rib and the groove are tapered. The combined state is stably maintained.

  According to the broach of the present invention, the relative rotation between the main body portion and the shell portion of the broach main body is restricted, and the row of cutting blades can be reliably prevented from being displaced before and after these connecting portions, and the high stability can be achieved. Quality cutting can be performed.

It is a side view showing a broach concerning one embodiment of the present invention. It is a figure which expands and shows the principal part (rib and groove vicinity) of the broach of FIG. It is a figure which shows the AA cross section of FIG. It is a side view which shows the conventional broach. It is a figure which expands and shows the rib and groove | channel vicinity of the broach of FIG. It is a figure which shows the BB cross section of FIG.

Hereinafter, a broach 1 according to an embodiment of the present invention will be described with reference to the drawings.
As shown in FIG. 1, the broach 1 of this embodiment includes a plurality of cutting blades 3 arranged on the outer periphery of an axial broach body 2, and the broach body 2 is placed in a prepared hole formed in a work material. While being inserted toward the tool feed direction D along the axis O direction of the broach body 2, the prepared hole is cut into a predetermined shape by a plurality of cutting blades 3.
The broach 1 is an assembly-type helical broach, and the broach 1 is rotated around the axis O while being fed in a tool feed direction D to a pre-formed hole formed in a work material. Is processed into a predetermined shape such as a helical internal gear shape.

  Here, the broach body 2 is inserted into the lower hole so that its axis O is coaxial with the central axis of the lower hole of the work material. In this specification, the direction (left side in FIG. 1) in which the broach main body 2 is fed to the work material in the direction of the axis O of the broach main body 2 is referred to as the tool feed direction D (or the front of the tool feed direction D). The direction opposite to this (the right side in FIG. 1) is referred to as the rear in the tool feed direction D. A direction orthogonal to the axis O is referred to as a radial direction, and a direction around the axis O is referred to as a circumferential direction.

  The broach main body 2 includes a shaft-shaped main body portion 4 having a large-diameter portion 5 and a small-diameter portion 6 that are adjacent to each other in the axis O direction, a cylindrical shell portion 7 that is detachably attached to the small-diameter portion 6, and a small-diameter portion 6. And a ring portion 8 capable of pressing the shell portion 7 toward the large-diameter portion 5 along the axis O direction.

  The main body portion 4 has a long multi-stage shaft shape extending in the direction of the axis O, and a front grip portion 9 is formed at the front end portion of the main body portion 4 in the tool feed direction D. The tool feed direction A rear grip 10 is formed at the rear end of D. Further, a front guide 11, a large diameter portion 5, and a small diameter portion 6 are formed in this order on the rear side of the front grip portion 9 in the main body portion 4 in the tool feeding direction D.

  The front grip portion 9 and the rear grip portion 10 are supported by a helical broaching machine (not shown). In the illustrated example, both the front grip portion 9 and the rear grip portion 10 have a round neck shape. The front gripping portion 9 and the rear gripping portion 10 may be, for example, a cotter shape, a DIN shape, a trapezoidal groove shape, or the like other than the round neck shape.

The front guide 11 has a round bar shape or a columnar shape.
The front guide 11 accurately positions and guides the cutting blade 3 (first blade 3a), which is first cut into the work material and is located in the foremost position in the tool feed direction D, in the radial direction with respect to the lower hole. It is provided for the purpose.

  The plurality of cutting blades 3 project radially outward on the outer periphery of the broach body 2, and these cutting blades 3 are along a lead L that is twisted about the axis O toward the rear in the tool feed direction D. Arranged in a spiral. A plurality of rows of the cutting blades 3 are formed at intervals in the circumferential direction.

  Specifically, the plurality of cutting blades 3 are arranged over the outer periphery of the large diameter portion 5 and the outer periphery of the shell portion 7 in the broach main body 2. In the present embodiment, among these cutting blades 3, a plurality of cutting blades 3 arranged on the outer periphery of the large-diameter portion 5 are outer diameter rising blades that drive the tooth profile of the helical internal gear in the tooth height direction and cut it. . Further, round blades for cutting a small-diameter portion (inner periphery) of the tooth profile are alternately formed on the outer end of the large-diameter portion 5 at the rear end in the tool feed direction D.

  Further, the plurality of cutting blades 3 arranged on the outer periphery of the shell portion 7 have tooth surfaces having tooth shapes cut by the outer diameter rising blades to a predetermined tooth height, that is, both groove wall surfaces of the torsion grooves of the work material. It is a tooth-thickening blade that is driven into the thickness direction, that is, the circumferential direction of the broach body 2 to form a predetermined tooth thickness.

  In the row of cutting blades 3, a gap between adjacent cutting blades 3 along the lead L is a blade groove. The blade groove between the cutting blades 3 on the outer periphery of the large-diameter portion 5 has an annular shape extending along the circumferential direction, and the blade groove of the large-diameter portion 5 is a straight shaft type. Further, the blade groove between the cutting blades 3 on the outer periphery of the shell portion 7 has a spiral shape, and the blade groove of the shell portion 7 is of an off-normal type.

  Of the end surface of the large-diameter portion 5 facing the shell portion 7 along the axis O direction and the end surface of the shell portion 7 facing the large-diameter portion 5 along the axis O direction, A rib 12 that protrudes toward the end surface and extends in the radial direction is formed, and a groove 13 that is recessed in a direction away from the one end surface and extends in the radial direction is formed on the other end surface.

  As shown in FIG. 2, in the present embodiment, the end face 14 facing the rear in the tool feed direction D in the large diameter portion 5 is the one end face, and the end face 14 is moved backward in the tool feed direction D. Ribs 12 that protrude toward the surface and extend along the radial direction are formed. Further, an end face 15 facing the front in the tool feeding direction D in the shell portion 7 is the other end face, and the end face 15 is recessed toward the rear in the tool feeding direction D and extends along the radial direction 13. Is formed.

  A pair of side surfaces (outer surfaces) 16 that face the width direction (vertical direction in FIG. 2) of the ribs 12 on one end surface 14 and are arranged back to back (arranged back to back) are connected to the other side along the axis O direction. It inclines so that it may mutually approach gradually as it goes to the end surface 15 side (right side in FIG. 2). Further, a pair of side surfaces (inner side surfaces) 17 facing each other in the width direction (vertical direction in FIG. 2) of the groove 13 on the other end surface 15 are arranged on one end surface 14 side (FIG. 2) along the axis O direction. Inclined so as to be gradually separated from each other as it goes to the left. The pair of side surfaces 16 and 17 are each formed in a planar shape, and the angles inclined with respect to the axis O in the side view shown in FIG. And the rib 12 and the groove | channel 13 are fitted by making a pair of mutual side surfaces 16 and 17 contact each other (facing side surfaces 16 and 17 mutually).

In addition, a gap is provided between the top surface 18 of the rib 12 and the bottom surface 19 of the groove 13 with the rib 12 and the groove 13 fitted in this manner. A gap is also provided between a portion of the one end surface 14 other than the rib 12 and a portion of the other end surface 15 other than the groove 13.
In the illustrated example, the width of the rib 12 (length in the width direction) and the width of the groove 13 are set to be smaller than the outer diameter of the small-diameter portion 6, but the present invention is not limited to this. And the width of the groove 13 may be set equal to or larger than the outer diameter of the small diameter portion 6.

  The ring portion 8 is screwed to the small diameter portion 6 so as to be able to advance and retreat in the axis O direction. Although not shown in particular, the outer periphery of the small-diameter portion 6 is male threaded, and the inner periphery of the ring portion 8 is female threaded so that they can be screwed together. An end surface facing the front in the tool feed direction D in the ring portion 8 is in contact with an end surface facing the rear in the tool feed direction D in the shell portion 7, and the ring portion 8 is screwed into the small diameter portion 6, thereby The portion 8 can press the shell portion 7 toward the front in the tool feed direction D (toward the large diameter portion 5).

  The small diameter portion 6 is formed with a stop groove 20 extending along the axis O. In the illustrated example, a plurality of annular retaining grooves 20 are formed at intervals in the direction of the axis O. Further, the ring portion 8 is provided with a pin member (not shown) that is advanced and retracted so as to be engageable with the stop groove 20. Specifically, a plurality of female screw holes 21 penetrating the ring portion 8 in the radial direction are formed in the ring portion 8 at intervals in the circumferential direction and the axis O direction. The pin member having a male threaded outer periphery is screwed so as to be able to advance and retreat in the radial direction. Then, by screwing the pin member into the female screw hole 21, the distal end portion of the pin member facing inward in the radial direction comes into contact with the stop groove 20, and these are engaged.

  According to the broach 1 of the present embodiment described above, the cylindrical shell portion 7 is detachably attached to the small diameter portion 6 of the main body portion 4 that forms the shaft shape in the broach main body 2. Of the end surface 14 facing the shell portion 7 side in the diameter portion 5 and the end surface 15 facing the large diameter portion 5 side in the shell portion 7, the rib 12 is formed on one end surface 14, and the groove 13 is formed on the other end surface 15. Is formed. The pair of side surfaces 16 facing the width direction of the rib 12 on one end surface 14 are inclined so as to gradually reduce the distance from each other toward the other end surface 15 side along the axis O direction. The pair of side surfaces 17 facing the width direction of the groove 13 in 15 are inclined so as to be gradually separated from each other toward the one end surface 14 along the axis O direction.

That is, the pair of side surfaces (outer side surface) 16 in the rib 12 and the pair of side surfaces (inner side surface) 17 in the groove 13 are both tapered, and the rib 12 and the groove having the corresponding side surfaces 16 and 17 are the same. 13 are fitted to each other. In this manner, the rib 12 and the groove 13 are taper-fitted, so that a clearance for engagement which has been conventionally required between the rib 12 and the groove 13 becomes unnecessary, and the main body portion 4 and the shell portion 7 The relative rotation around the axis O is reliably regulated.
This reliably prevents the row of the cutting blades 3 from being shifted before and after the axis O in the boundary between the outer periphery of the large-diameter portion 5 of the main body 4 and the outer periphery of the shell 7. Therefore, stable and high-quality cutting can be performed.
In order to accurately align the rows of the cutting blades 3 before and after the connecting portion on the outer periphery of the broach body 2 as described above, the rib 12 and the groove 13 are fitted when the broach 1 is manufactured. Therefore, it is preferable to produce a plurality of cutting blades 3 on the outer periphery of the broach body 2.

Further, in the present embodiment, since the clearance for engagement between the rib 12 and the groove 13 becomes unnecessary, the clearance in the direction of the axis O is also unnecessary, so that a complicated adjustment work as in the past is unnecessary. .
Further, since the relative rotation around the axis O between the main body portion 4 and the shell portion 7 is surely restricted, the helical broach described in the present embodiment is not limited to the helical broach. Even in a broach, that is, a broach in which the row of cutting blades 3 extends in parallel with the axis O direction, the machining accuracy is stably secured by applying the present invention.

  Further, since the ring portion 8 capable of pressing the shell portion 7 toward the large diameter portion 5 along the axis O direction is detachably attached to the small diameter portion 6, the rib 12 and the groove 13 are taper-fitted. The combined state is stably maintained, and the row of the cutting blades 3 is more reliably prevented from being displaced.

  In addition, since the ring portion 8 is screwed to the small diameter portion 6 so as to be able to advance and retreat in the axis O direction, the rib 12 and the groove can be easily operated by screwing the ring portion 8 into the small diameter portion 6. 13 can be securely taper-fitted. That is, since the rib 12 and the groove 13 can be easily and reliably fitted, workability at the time of component replacement and maintenance is improved, and the accuracy of the cutting process is stably increased.

  Further, the small diameter portion 6 is formed with a stop groove 20 extending around the axis O, and the ring portion 8 is provided with a pin member that advances and retracts so as to be engageable with the stop groove 20. By engaging the pin member with the stop groove 20, the relative movement between the ring portion 8 and the small diameter portion 6 is restricted, and the ring portion 8 stably presses the shell portion 7. Is stably maintained in a taper-fitted state.

  The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

  For example, in the above-described embodiment, the end face 14 facing rearward in the tool feed direction D in the large diameter portion 5 is the one end face and the rib 12 is formed, and the shell portion 7 faces forward in the tool feed direction D. Although the end face 15 is the other end face and the groove 13 is formed, the present invention is not limited to this. That is, the groove 13 may be formed on the end surface 14 of the large diameter portion 5, and the rib 12 may be formed on the end surface 15 of the shell portion 7.

  Although the ring portion 8 is detachably disposed on the small diameter portion 6, the ring portion 8 may not be provided.

  In the above-described embodiment, the broach 1 cuts the prepared hole of the work material to form the helical internal gear shape. However, the present invention is not limited to this. In other words, the broach 1 may be any material that can be cut into a predetermined shape by broaching the prepared hole of the work material, and is cut into a serration shape or key groove shape other than the above-described helical internal gear shape. It does not matter.

  In addition, in the range which does not deviate from the meaning of this invention, you may combine each structure (component) demonstrated by the above-mentioned embodiment, a modified example, a note, etc., addition of a structure, omission, substitution, others It can be changed. Further, the present invention is not limited by the above-described embodiments, and is limited only by the scope of the claims.

DESCRIPTION OF SYMBOLS 1 Broach 2 Brooch main body 3 Cutting blade 4 Main body part 5 Large diameter part 6 Small diameter part 7 Shell part 8 Ring part 12 Rib 13 Groove 14 End surface (one end surface)
15 End face (the other end face)
16, 17 Side 20 Stop groove D Tool feed direction O Broach body axis

Claims (4)

A plurality of cutting blades are arranged on the outer periphery of the broach main body having an axial shape, and the broach main body is inserted into a pilot hole formed in the work material in the tool feeding direction along the axial direction of the broach main body, and A broach that cuts the prepared hole into a predetermined shape with a plurality of cutting blades,
The broach body is
An axial main body having a large diameter portion and a small diameter portion adjacent to each other in the axial direction;
A cylindrical shell portion detachably attached to the small diameter portion,
The plurality of cutting blades are arranged over the outer periphery of the large-diameter portion and the outer periphery of the shell portion, and the cutting blades of the large-diameter portion and the shell portion are twisted about the axis toward the rear in the tool feed direction. Arranged in a spiral along the lead
Of the end surface facing the shell portion side along the axial direction of the large diameter portion and the end surface facing the large diameter portion side along the axial direction of the shell portion, one end surface is on the other end surface. A rib extending in the radial direction orthogonal to the axis is formed, and a groove extending in the radial direction and recessed in a direction away from the one end surface is formed on the other end surface;
A pair of side surfaces facing the width direction of the ribs on the one end surface are inclined so as to gradually approach each other toward the other end surface side along the axial direction,
A pair of side surfaces facing the width direction of the groove on the other end surface are inclined so as to be gradually separated from each other toward the one end surface side along the axial direction,
The rib and the groove are fitted so that the pair of side surfaces contact each other,
The pair of side, Ri angle identical der mutually inclined relative to the axis,
The broach fixed in the state which the said large diameter part and the said shell part do not rotate relatively . The broach according to claim 1,
The broach, wherein the small diameter portion is detachably mounted with a ring portion capable of pressing the shell portion toward the large diameter portion along the axial direction. The broach according to claim 2,
The broach, wherein the ring part is screwed to the small diameter part so as to be able to advance and retreat in the axial direction. The broach according to claim 2 or 3,
A stop groove extending along the axis is formed in the small diameter portion,
The broach according to claim 1, wherein a pin member is provided in the ring portion so as to be able to engage with and retract from the retaining groove.

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