JP2000254750A - Deburring method for work hole and deburring punch die - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a deburring method and a deburring die advantageous for suppressing a strain of a work. SOLUTION: A blanking die 1, which has an inclined die face 12 reducing the outer diameter toward a tip, and a work 3, which has burr 33 covering at least part of a work hole 31, are used. By relatively inserting the blanking die 1 in the work 3 the blanking die 1 is relatively inserted into the burr 33 covering the work hole 31 from its tip. By this method, the bur 33 is blanked to be removed from the work hole 31, further, an inclined die face 12 of the blanking die 1 is brought into contact with the inner wall face of the hole part immediately after deburring among the work holes 31 of the work 1 and is worked. The outer diameter of the large diameter end 12a of the inclined die face 12 is set larger than the inner diameter of the hole part deburred among the work holes 31.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and a punch for removing burrs from a work hole formed in a work such as a forged product.

[0002]

2. Description of the Related Art In a work having a work hole, a burr that covers the work hole may be formed due to molding conditions. For example, in a forged product work having a work hole, a relatively thick forged burr that covers the work hole is formed. When burrs that cover the work hole are formed in this way, the burrs are an obstacle, and therefore, burrs are punched out and removed from the work hole.

As shown in FIG. 9, a conventionally used deburring punch mold 100 has an enlarged-diameter inclined mold surface 110 whose outer diameter increases toward the tip. Then, the burr punch 100 is relatively pressed into the work hole 310 of the work 300 from the tip thereof, whereby the burr 330 of the work 300 is punched out and removed from the work hole 310.

[0004]

However, in the above-described deburring method, distortion often occurs in the deburred work 300. In particular, when the work 300 is a long object such as a lower arm mounted on a suspension mechanism of a vehicle, distortion is likely to occur.

The reason is presumed as follows. Burr 3
Immediately after punching 30, the diametrically enlarged inclined die surface 110 of the deburring punch die 100 protrudes beyond the work hole 310 in the direction of arrow A1, as indicated by the imaginary line in FIG. Therefore, it is necessary to pull out the enlarged-diameter inclined die surface 110 of the deburring punch die 100 from the work hole 310 in the direction of arrow A2 to be separated.

However, immediately after the burr removal, the inner wall surface of the hole portion of the work hole 310 from which the burr has been removed tends to be displaced toward the inner diameter side due to the influence of springback. When springback occurs as described above, when the burr-removing punch die 100 is pulled out from the hole portion where the burr has been removed in the direction of the arrow A2 in the direction of the arrow A2, as can be understood from FIG. The enlarged diameter end of the enlarged diameter inclined mold surface 110 corresponds to the inner wall surface of the hole. This is the resistance when the deburring punch 100 is pulled out of the work hole 310, and it is presumed that this becomes a factor of distortion of the work 300.

When the workpiece 300 is a hot forged product, deburring is also performed at a high temperature. Therefore, due to the drop in the temperature of the work 300, the work hole 3
Numeral 10 is easily displaced by heat shrinkage in a direction in which the inner diameter becomes smaller. Therefore, the deburring punch 100 is moved to the work hole 31.
At the time of removal from zero, the enlarged end of the enlarged inclined surface 110 of the burr removing punch die 100 hits the inner wall surface of this hole portion, which is assumed to be a factor of distortion of the work 300.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a deburring method for a work hole and a deburring punch die which are advantageous for suppressing distortion of a work at the time of deburring. And

[0009]

According to the present invention, there is provided a method for removing burrs from a work hole, comprising the steps of: removing a burr having an inclined surface with an outer diameter decreasing toward a tip; and a burr covering at least a part of the work hole. Using a provided work, press the deburring punch relative to the work and press the burr punch relatively into the burr that covers the work hole from the tip of the burr. In addition to the removal, the slanted surface of the deburring punch die is slid on the inner wall surface of the hole of the work immediately after the deburring is performed.

A deburring punch die according to the present invention can be used in the above-described deburring method, and burrs for punching out burrs covering at least a part of a work hole formed in a work and removing the burr from the work hole. It is a punch type, and has an inclined mold surface whose outer diameter decreases toward the tip, and the outer diameter of the large-diameter end of the inclined mold surface is larger than the inner diameter of the hole portion of the work hole where deburring was performed. It is characterized by being set.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The deburring punch used in the method of the present invention has an inclined surface whose outer diameter decreases toward the tip. The inclined surface can generally be configured as a conical surface. Assuming that the inclination angle of the inclined mold surface with respect to a parallel line parallel to the central axis of the deburring punch mold is α1, the lower limit of α1 is 0.1 degree and 0, although it depends on the material of the work, the inner diameter of the work hole, and the like. An arbitrary value among 0.3 degrees, 0.5 degrees, 0.8 degrees, etc. can be adopted, and the upper limit value is 1, 2, 3, or
Any value among 4, 5, 10, and the like can be adopted. Therefore, α can be, for example, 0.1 to 5 degrees.

The cross-sectional shape of the deburring punch used in the method of the present invention corresponds to the cross-sectional shape of the inner wall surface of the work hole of the work. The work used in the method of the present invention has a work hole and a burr that covers at least a part of the work hole. The work may be a forged product or a cast product. The forged product may be a hot forged product, a cold forged product, or a warm forged product. The material of the work is not particularly limited, and a ferrous material such as carbon steel or alloy steel or a non-ferrous material such as aluminum can be employed.

In the method of the present invention, the deburring punch is moved relatively to the work so that the deburring punch is pressed into the burr covering the work hole from the tip thereof. Thereby, burrs are punched out and removed from the work holes. Further, the inclined wall surface of the deburring punch is brought into contact with the inner wall surface of the hole portion of the work immediately after deburring is performed, and the inner wall surface of the hole portion is slid. This is advantageous in reducing the cutting allowance when cutting the inner wall surface of the deburred hole portion.

When the inner wall surface of the hole portion is not cut, the inner wall surface of the hole portion can be strengthened by sliding the inner wall surface of the hole portion. In particular, when the temperature of the work is in a normal temperature range or a temperature range close to this, it is possible to expect strengthening by ironing. A deburring punch type according to the present invention is a deburring punch type for punching out a burr covering at least a part of a work hole formed in a work and removing the burr from the work hole. The deburring punch die according to the present invention has an inclined die surface whose outer diameter decreases toward the tip. The outer diameter of the large-diameter end of the inclined mold surface is set to be larger than the inner diameter of the hole portion of the work hole from which the deburring has been performed. Thereby, the slanting surface of the deburring punch is brought into contact with the inner wall surface of the hole portion of the work hole where the deburring has been performed, and the inner wall surface of the hole portion can be effectively slid.

[0015] In the deburring punch mold according to the present invention, the inclined mold surface has a first inclined mold surface whose outer diameter decreases toward the distal end, and a large-diameter end of the first inclined mold surface and is connected to the distal end. It is possible to adopt a configuration having a second inclined surface whose outer diameter decreases as it goes. In this case, the inclination angle of the first inclined mold surface with respect to the parallel line of the central axis of the deburring punch mold is α
If the angle of inclination of the second inclined surface with respect to the parallel line of the central axis is β, then α <β. This ensures the deburring performance of the deburring punch mold,
The removability of the deburring punch type can be secured.

Β can be larger than α by γ (β = α + γ). For example, γ is 0.2 °, 0.3 °, 0.5 °, 1 °, etc.
It can be 1.5 degrees, 2 degrees, and 3 degrees. However, it is not limited to these.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) A first embodiment will be described below with reference to the drawings. This embodiment is a case where the present invention is applied to deburring of a hot forged product. The deburring punch die 1 used in the present embodiment is made of metal having excellent heat resistance and impact resistance, has a circular cross-section in a circular cross-section, and has a tip surface 10 along a direction perpendicular to the axis. And an inclined surface 12 extending from the distal end surface 10 along the axial length direction.

The inclined mold surface 12 has a ring-shaped small-diameter end 12a on the tip surface 10 side and a ring-shaped large-diameter end 12c on the side moving away from the tip surface 10. The inclined die surface 12 makes one round around the central axis Pc of the deburring punch die 1, and has a straight conical shape whose outer diameter gradually decreases toward the tip (the upper end in the drawing) of the deburring die 1. No.
The outer diameter Do of the large-diameter end 12c of the inclined mold surface 12 is
1 is set to be larger than the inner diameter Di of the hole portion 31c from which the burrs have been removed.

Assuming that the inclination angle of the inclined mold surface 12 with respect to a parallel line Pk parallel to the central axis Pc of the deburring punch mold 1 is α1, α1 is an arbitrary value of 0.5 to 5 degrees, especially 0.6.
It is set to an arbitrary value of -2.5 degrees. However, it is not limited to this. The work 3 used in the present embodiment includes a main body 30 and a ring 3 having a substantially circular work hole 31 connected to an end of the main body 30.
2 and a relatively thick burr 33 covering and closing the work hole 31
And The work 3 is of a carbon steel type, and is subjected to deburring through hot land forging and finish forming.

In the present embodiment, the work 3 is in a red-hot state or a high-temperature state close to the red-heat state at the time of deburring. The temperature of the work 3 is estimated to be about 900 to 1100 ° C.
On the other hand, the deburring punch die 1 receives heat transfer from the work 3 at the time of deburring, but has a lower temperature than the work 3. In the present embodiment, the deburring punch die 1 is set in a fixed state at the time of deburring. Then, with the work 3 held by the work holding means 40, the work 3 is pushed down by the work holding means 40 in the direction of arrow Y1, as shown in FIG. That is, the deburring punch 1 is relatively moved with respect to the work 3 so as to approach. As a result, the burr punch 1 is relatively pressed into the burr 33 covering the work hole 31 from the tip thereof. Therefore, the burr 3 covering the work hole 31
3 is punched out and removed from the work hole 31 by a shearing force.

In the present embodiment, as can be understood from FIG.
1, and the deburring is performed. Immediately after the deburring, the inclined die surface 12 of the deburring punch die 1 is provided on the inner wall surface of the hole portion 31c of the work 3 where the deburring has been performed. Contact under high pressure. As a result, work hole 3
The inner wall surface of the hole portion 31c from which burrs have been removed is slid. That is, the inclined die surface 12 of the punch 1 is continuously slid on the inner wall surface of the hole portion 31c immediately after the deburring. This defines the inner wall surface of the hole portion 31c immediately after the deburring. In the present embodiment, since the inclined mold surface 12 of the deburring punch mold 1 increases in diameter from the small-diameter end 12a to the large-diameter end 12c, a force in the radially increasing direction is applied to the ring portion 32 of the work hole 31. Can be provided.

In this embodiment, since the inclined mold surface 12 of the burr punch 1 having a straight conical surface is relatively pressed into the hole portion 31c immediately after the burr removal, a work hole is formed as shown in FIG. 31, the first inner wall surface 35a
And a second inner wall surface 35c processed by the inclined mold surface 12. In the axial direction, the axial length of the second inner wall surface 35c is larger than the axial length of the first inner wall surface 35a.

In this embodiment, when removing burrs, the workpiece 3 is in a red hot state or at a high temperature close to the red hot state. On the other hand, since the temperature of the deburring punch die 1 is considerably lower than that, the inner wall surface of the hole portion 31c immediately after the deburring can be well defined while suppressing seizure. Further, at the time of deburring, an effect of restraining the inner diameter of the hole portion 31c of the work 3 by the inclined mold surface 12 of the deburring punch die 1 and correcting the dimension of the inner diameter can be expected.

In this embodiment, the work holding means 4 holds down the work 3 and presses down the work 3 relatively.
At 0, the bottom dead center of the depression is fixed. For this reason, the press-in amount by which the inclined mold surface 12 of the deburring punch mold 1 is pushed into the work hole 31 is constant. In other words, in this embodiment, a pressing amount regulating means for keeping the inclined mold surface 12 of the deburring punch mold 1 constant or substantially constant is used. Therefore, it is possible to prevent the inclined mold surface 12 of the deburring punch mold 1 from being excessively pushed into the work hole 31. Consequently, it is possible to suppress the conical inclined mold surface 12 of the deburring punch mold 1 from excessively expanding the inner wall surface of the hole portion 31c of the work.

After deburring is completed as described above, FIG.
As can be understood from FIG. 3, the work 3 is lifted relatively in the direction of arrow Y2 with respect to the deburring punch 1, and the deburring punch 1 is moved relative to the work 3. As a result, the burr punch 1 is pulled out of the work hole 31 of the work 3 and detached. When the deburring punch mold 1 is slightly moved in the direction in which the deburring punch mold 1 comes off from the work 3 in this way, that is, in this embodiment, the work 3 that has been in contact with the inclined mold surface 12 of the burr removing punch mold 1 is slightly moved. However, if it is lifted, the inclined mold surface 12 of the deburring punch 1 and the hole 31c are formed.
A gap can be immediately formed between the inner wall surface and the inner wall. Therefore, in the present embodiment, the deburring punch die 1 according to the prior art is used.
Unlike the case of 00, even if the inner diameter shrinks due to the spring back or the temperature drop of the work hole 31, the inclined mold surface 12 of the deburring punch die 1 can be separated from the hole portion 31c of the work hole 31 without any trouble. Therefore, it is advantageous for suppressing distortion of the work 3 at the time of deburring.

(Second Embodiment) The second embodiment is basically the same as the first embodiment shown in FIGS. 1 to 3, and will be described with reference to FIGS. In the second embodiment,
The work 3 to be deburred is not a hot forged product but a cold forged product forged in a normal temperature region. Therefore, deburring is also a cold deburring method performed in the normal temperature range.

Also in this embodiment, as can be understood from FIG.
Is held by the work holding means 40, the work 3 is pushed down by the work holding means 40 in the arrow Y1 direction. As a result, the burr punch 1 is relatively pressed into the burr 33 covering the work hole 31 from the tip thereof. Therefore burr 33
Is punched out and removed from the work hole 31.

Also in this embodiment, since the deburring punch die 1 is pressed into the work hole 31 after the deburring, the hole 3 of the work hole 31 of the work 3 from which the deburring has been performed.
The inclined mold surface 12 of the deburring punch mold 1 is slid on the inner wall surface of 1c under high pressure. Thereby, the inner wall surface of the hole portion 31c of the work hole 31 from which the burrs have been removed is ironed. That is, the inclined die surface 12 of the deburring punch die 1 continues to iron the inner wall surface of the hole portion 31c immediately after the deburring. This is advantageous for strengthening the inner wall surface of the hole portion 31c immediately after deburring and for stabilizing the inner diameter of the inner wall surface.

(Third Embodiment) FIG. 4 shows a third embodiment.
The third embodiment is basically the same as the first embodiment. The same parts are denoted by the same reference numerals. However, in the third embodiment, a lower restraint 60 that restrains the outer peripheral portion of the work 3 is used.
A cylindrical ejector 62 for discharging the workpiece 3 from the upper and lower constraint dies 61 and 60 is provided.
The ejector 62 and the deburring punch die 1B are arranged in the insertion hole 60a inside the restraining lower die 60 in a vertical axis type. The constraint upper die 61 has a press-in hole 61c into which the deburring punch die 1B is pressed.

In this embodiment, the same operation and effect as those of the first embodiment can be obtained.
This is advantageous for suppressing distortion. In the present embodiment, since the lower constraint mold 60 and the upper constraint mold 61 are provided, it is more advantageous to suppress the outer wall surface of the ring portion 32 of the work 3 from bulging and deforming during deburring. . (Fourth Embodiment) A fourth embodiment is shown in FIG. The fourth embodiment is basically the same as the first embodiment. The same parts are denoted by the same reference numerals. In this embodiment, the same operation and effect as those of the first embodiment can be obtained, which is advantageous for suppressing the distortion of the work at the time of deburring.

Also in this embodiment, the deburring punch die 1C
Are arranged in a vertical axis type. The inclined mold surface 12 includes a first inclined mold surface 12m formed of a straight conical surface whose outer diameter decreases toward the tip, and a large-diameter end 1 of the first inclined mold surface 12m.
And a second inclined mold surface 12r formed of a straight conical surface whose outer diameter decreases toward the tip end following 2k. The first with respect to the parallel line Pk of the central axis Pc
If the inclination angle of the inclined mold surface 12m is α and the inclination angle of the second inclined mold surface 12r with respect to the parallel line Pk is β, then α <β.

In order to secure a shearing force at the time of deburring, it is preferable that the inclination angle of the inclined mold surface with respect to the central axis Pc is small. However, in this case, since the amount of the inclined mold surface plastically deforming the inner wall surface of the work hole is reduced, the degree of sliding processing of the burring trace is reduced. In this regard, in the present embodiment, as can be understood from FIG. 5, the inclination angle α of the first inclined mold surface 12m on the tip side where the burr 33 of the work 3 is punched out.
Is small, which is advantageous for securing a shearing force on the burr 33 at the time of punching. Further, since the inclination angle β of the second inclined surface 12r following the first inclined surface 12m is larger than the inclination angle α, the inclination angle of the entire inclined surface 12 is equal to that of the case where the inclination angle is α. , Work hole 31
After the burr 33 is punched out, the inner wall surface of the work hole 31 is machined to secure the amount of plastic deformation. Further, since the inclination angle β of the second inclined die surface 12r is increased after punching, the operation of pulling out the deburring punch die 1 from the work hole 31 immediately after deburring and detaching it becomes easy. That is, the present embodiment secures the removability of the deburring punch die 1C while securing the punching properties of the burr.

(Fifth Embodiment) FIG. 6 shows a fifth embodiment.
The fifth embodiment is basically the same as the first embodiment. The same parts are denoted by the same reference numerals. In this embodiment, the same operation and effect as those of the first embodiment can be obtained, which is advantageous for suppressing the distortion of the work 3 at the time of deburring.

Also in this embodiment, a deburring punch type 1D
An inclined mold surface 12 is formed on the tip side of the. The inclined mold surface 12 is formed of a straight conical surface whose outer diameter decreases toward the tip. On the large diameter side of the inclined mold surface 12 of the deburring punch mold 1D, a groove portion including a ring-shaped inverted tapered portion 12x is formed so as to make one round. Reverse taper part 12
x is a taper whose diameter decreases toward the rear end of the deburring punch die 1D, and is opposite to the taper of the inclined die surface 12. The groove may not be a groove as long as the groove is a reverse taper.

Also in this embodiment, the hole 3 of the work 3
Immediately after deburring, the deburring mark of 1c can be immediately slid on the inclined die surface 12 of the deburring punch die 1. Further, since the reverse tapered portion 12x is formed on the large diameter side of the inclined mold surface 12, it is advantageous to suppress excessive sliding processing of a portion other than the flash mark. Therefore, it is advantageous to prevent an excessive diameter expanding force from acting on the ring portion 32 of the work 1. Therefore, in this embodiment, the ring 3
2 is suitable for the work 1 where it is not preferable that an excessive diameter expanding force acts on the inner wall surface.

(Application Example) FIGS. 7 and 8 show application examples.
In the present example, the work 3 is a forged lower arm as a long object, which is a suspension component mounted on a suspension mechanism of a vehicle. The work 3 includes a main body 30 that is elongated and bent, and a ring 32 that is connected to one end of the main body 30 and has a substantially circular work hole 31. Before deburring, the work hole 31 is formed with a burr 33 that covers and closes the work hole 31. The work 3 is of a carbon steel type, and is subjected to deburring by a deburring punch die 1 after rough land forming and finish forming by hot forging. The work 3 is a long object, and the main body 30 is also relatively lifted in the arrow Y2 direction.
If the resistance is high when the deburring punch die is removed from the work hole at the time of deburring, the work 1 is likely to be distorted. Therefore, it is preferable to apply this embodiment that can suppress the occurrence of distortion.

(Other Example) In the first embodiment described above, the work hole 31 of the work 3 is formed in a circular shape, and the cross-sectional shape of the deburring punch die 1 also corresponds to the shape of the work hole 31. Although it was formed in a circular shape, the work 3
The work hole has a substantially square shape such as a substantially square shape, and the cross-sectional shape of the deburring punch type may be substantially a square shape such as a substantially square shape so as to correspond to the shape of the work hole.

In the first embodiment described above, at the time of deburring, the work 3 is pushed down in the direction of the arrow Y1 with the deburring punch die 1 fixed. However, the present invention is not limited to this. The deburring punch die 1 may be lifted and deburred in this state. In short, it suffices to move the deburring punch die 1 relatively to the work 3 so as to approach it.

In addition, the present invention is not limited to the embodiment described above and shown in the drawings, but can be appropriately changed as needed without departing from the scope of the invention.

[0040]

According to the method of the present invention, a burr-removing punch die is relatively inserted into the burr covering the work hole from the tip thereof, and the burr is punched out and removed from the work hole.
The slanting surface of the deburring punch is brought into contact with the inner wall surface of the hole portion of the work hole where the deburring has been performed, and the inner wall surface of the hole portion is slid.

When the burr-removing punch die is slightly moved in the direction in which the burr-removing punch die is removed from the work when the inclined die surface of the burr-removing punch die is separated from the work hole of the work, the slanting die surface of the burr-removing punch die and the hole portion are removed. A gap can be immediately formed between the inner wall surface. Therefore, unlike the deburring punch type according to the related art, it is advantageous to detach the inclined mold surface of the deburring punch type from the hole portion of the work hole without any trouble.

Therefore, even if spring back occurs at the deburring mark of the work hole and the inner diameter shrinks due to a temperature drop at the deburring mark of the work hole, the inclined die surface of the deburring punch is moved to the hole of the work hole. It is advantageous to be able to leave without any trouble. According to the method of the present invention, since the inclined mold surface of the deburring punch is brought into contact with the inner wall surface of the hole portion of the work hole of the work immediately after the deburring, the hole portion immediately after the deburring is performed. The sliding process can be continuously performed on the inner wall surface of the slab, which is advantageous for improving the deburring mark. The deburring punch mold according to the present invention includes:
It can be used to implement the method described above. In particular, since the outer diameter of the large-diameter end of the inclined mold surface is set to be larger than the inner diameter of the hole portion of the work hole from which the deburring was performed, the hole from which the deburring was performed among the work holes of the work is performed. The inner wall surface of the portion is brought into contact with the inclined die surface of the deburring punch die, and the inner wall surface of the hole portion can be slid and the burring trace can be made good.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a state immediately before a burr punch punch contacts a burr of a work.

FIG. 2 is a cross-sectional view showing a state immediately after a burr of a work is removed by a burr punch.

FIG. 3 is a cross-sectional view showing a state in which a deburring punch is pulled out of a workpiece hole of a workpiece immediately after deburring the workpiece with a deburring punch.

FIG. 4 is a sectional view according to a third embodiment.

FIG. 5 is a sectional view according to a fourth embodiment.

FIG. 6 is a sectional view according to a fifth embodiment.

FIG. 7 is a side view showing a cross section of a part of a work according to an application example.

FIG. 8 is a plan view of a workpiece according to an application example.

FIG. 9 is a cross-sectional view showing a state in which burrs of a work are removed by a deburring punch mold according to the conventional technique.

FIG. 10 is a cross-sectional view showing a state in which the deburring punch is released from the workpiece immediately after the burr of the workpiece is removed by the deburring punch according to the related art.

[Explanation of symbols]

In the drawing, reference numeral 1 denotes a deburring punch type, 12 denotes an inclined die surface, 3 denotes a work, 31 denotes a work hole, and 33 denotes a burr.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Yoshihiro Ito 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Corporation F-term (reference) 4E048 AA01 4E087 CB01 DB02 HA82

Claims (2)

[Claims] 1. A deburring punch having a slanting die surface whose outer diameter decreases toward a tip end and a work having a burr covering at least a part of a work hole, wherein the deburring punch is formed on the work. By relatively moving the mold, the deburring punch mold is relatively pressed into the burr covering the work hole from the tip thereof, and the burr is punched out and removed from the work hole. A deburring method for a work hole, characterized in that the slanted surface of the deburring punch is slid on the inner wall surface of the hole immediately after the deburring is performed. 2. A deburring punch type for punching out burrs covering at least a part of a work hole formed in a work and removing the burr from the work hole, wherein an inclined die surface whose outer diameter decreases toward a tip end is formed. In addition, an outer diameter of a large-diameter end of the inclined mold surface is set to be larger than an inner diameter of a portion of the work hole from which deburring has been performed.