JP6673760B2 - Projection forming apparatus, projection forming method - Google Patents

Description

  The present invention relates to a projection molding device, a projection molding method, and a molded product.

When forming a protrusion on a plate-shaped workpiece such as a steel plate, if the height of the protrusion is considerably larger than the thickness of the plate, forming is performed by drawing.
However, the drawing process requires that the distance between the side surface of the punch and the inner surface of the die hole be equal to or greater than the plate thickness. In the case of drawing, R (roundness) at the corners of the punch and the die is large. For this reason, it is impossible to form a projection having a sharp edge.

In the case of forming a projection having a sharp edge, a half blanking process is performed by a fine blanking method.
The fine blanking method is a method in which a workpiece is plastically deformed by applying a compressive force to the workpiece to perform shearing with high accuracy.
However, the fine blanking method is difficult to form when the height of the projection is equal to or greater than the plate thickness. This is because, in general, the punch diameter and the die hole diameter are substantially the same, so that when the height of the projection is greater than or equal to the plate thickness, the workpiece is cut by shearing force and cannot be processed.

  For this reason, a punch having a diameter smaller than the die hole diameter is pressed against the workpiece, and the lower surface of the workpiece enters the die hole while forming a recess, and at the same time, the workpiece is pressed by the punch and the punch holder. In addition, a technology has been developed in which a half forging is performed using a cold forging die that causes compression deformation in the pinching portion (see Patent Document 1).

Japanese Patent No. 3339363

However, in the above-described conventional technology, the strength of a portion of the workpiece to be sandwiched between the punch and the die hole is not sufficient, and a crack may be formed in this portion.
An object of the present invention is to provide a projection molding apparatus, a projection molding method, and a molded article that can be formed to have a height equal to or greater than the plate thickness, have a sharp edge, and prevent the occurrence of cracks.

  The present invention provides a dice part provided with a dice hole, a large punch part capable of moving back and forth in a first direction toward the dice part side and having a size that cannot be inserted into the dice hole, and the large punch part And a punch having a small punch portion having a size large enough to be inserted into the die hole, protruding from the die portion side, and a part of the workpiece disposed between the die portion and the punch portion. By pressing the workpiece toward the die section by the punch section, thereby deforming the workpiece to form a projection section.

  In the protrusion forming apparatus, a distance d1 between a side surface of the small punch portion and a side surface of the large punch portion and a distance d2 between a side surface of the small punch portion and an inner surface of the die hole are in a relationship of d2 <d1. Is preferred.

  In the projection forming apparatus, it is preferable that a distance d2 between a side surface of the small punch portion and an inner surface of the die hole and a plate thickness T of the workpiece have a relationship of d2 <T.

  It is preferable that the lower surface of the small punch portion is provided with a slope inclined in a direction in which the thickness of the small punch portion becomes thinner toward the edge of the small punch portion.

  The present invention provides a placing step of placing a workpiece on a die portion provided with a die hole, a large punch portion having a size that cannot be inserted into the die hole, and the die portion side from the large punch portion. A punch portion having a small punch portion that is large enough to be inserted into the die hole and is moved in a first direction toward the die portion side, and a work piece disposed between the die portion and the punch portion is moved. A punching step of pressing a part of the body toward the die section side by the punch section to deform the workpiece to form a projection section.

  In the projection forming method, a distance d1 between a side surface of the small punch portion and a side surface of the large punch portion and a distance d2 between a side surface of the small punch portion and an inner surface of the die hole have a relationship of d2 <d1. Is preferred.

  In the projection forming method, it is preferable that a distance d2 between a side surface of the small punch portion and an inner surface of the die hole and a thickness T of the workpiece have a relationship of d2 <T.

  In the projection forming method, in the punching step, a slope inclined in a direction in which the thickness of the small punch portion becomes thinner toward an edge of the small punch portion is provided on a lower surface of the small punch portion. It is preferable that the method includes a first step of forming a projection by using a punched part, and a second step of forming a projection by using a punch having a flat lower surface of the small punched part.

  The present invention also relates to a molded product including a flat portion having a thickness T and a protrusion protruding from one surface side of the flat portion, wherein the other surface of the protrusion in the molded product has a first surface. A first concave portion having a width S1 and a second concave portion further formed from the first concave portion and having a second width S2, and a thickness d2 of a side wall portion in the second concave portion; The thickness T of the flat portion is a molded product satisfying the relationship of d2 <T.

  The molded article can be formed so that H ≧ T when the height H is from the one surface of the flat portion to the upper surface on the one surface side of the protrusion.

  Further, in the molded product, it is preferable that a width S1 of the first concave portion, a width S2 of the second concave portion, and a width S3 of the protrusion on the one surface side satisfy a relationship of S2 <S3 <S1.

  It is possible to provide a projection molding apparatus, a projection molding method and a molded article in which a height equal to or greater than the plate thickness can be formed, the edge is sharp, and the generation of cracks is prevented.

1A and 1B are schematic diagrams of a projection forming apparatus, in which FIG. 1A shows a state before processing of a workpiece, and FIG. 1B shows a state after processing of the workpiece. (A) is a photograph of the seat gear provided with the downward projection W1 as viewed from below, and (b) is a photograph of the seat gear provided with the downward projection W1 as viewed from above. It is an A section enlarged view of FIG.1 (b). FIG. 3 is a partial cross-sectional view of a formed product W01 after processing. 7A is a view showing a comparative example, in which FIG. 7A shows a state in which a workpiece is arranged on a die, and FIG. 7B shows a state in which a punch is lowered to form a projection on the workpiece. 4 is a graph showing the results of measuring the hardness of the protrusions P1 to P4 in FIG. 3 formed in the present embodiment. FIG. 4 is a diagram showing a second embodiment of the present invention, and corresponds to FIG. 3 of the first embodiment. FIG. 4 is a partial cross-sectional view of a molded product W02 after processing. FIG. 10 is a diagram illustrating a fourth embodiment of the present invention, and corresponds to FIG. 3 of the first embodiment. It is a fragmentary sectional view of the molded article W04 after processing.

(1st Embodiment)
Hereinafter, an overall configuration of a projection forming apparatus 1 according to an embodiment of the present invention will be described with reference to the drawings. The projection forming apparatus 1 is an apparatus for forming a projection on a plate-shaped workpiece W such as a steel plate. FIG. 1A shows the projection W1 in which the workpiece W is arranged on the projection forming apparatus 1. FIG. 1B is a schematic view showing a state in which the protrusion W <b> 1 has been formed on the workpiece W arranged in the protrusion forming apparatus 1.

The projection forming apparatus 1 of the present embodiment is used, for example, when forming a projection W1 on a seat gear as shown in FIG. FIG. 2A is a photograph of the seat gear provided with the downward protrusion W1 as viewed from below, and FIG. 2B is a photograph of the seat gear provided with the downward protrusion W1 as viewed from above. In the case of a seat gear, it is preferable that the surface area of the projection W1 on the side in contact with the die hole 12a is large in order to improve the efficiency of the rotational torque.
In the following description, a case where the protrusion W1 is formed so as to protrude downward as shown in FIG. 2B will be described.

  The projection forming apparatus 1 includes a fixing unit 10, a moving unit 30 that moves up and down with respect to the fixing unit 10, and a pressing unit 50 that is held by the moving unit 30 and moves further with respect to the moving unit 30. . Note that the term “up and down” refers to the direction of the arrow shown in FIG. The direction is called upward.

The fixing part 10 includes a die holder 11, a die part 12, and a guide post 13.
The die holder 11 is manufactured by a substantially rectangular thick plate member. The shape of the die holder 11 is not limited to a rectangle. A through hole 11 a is provided in the center of the die holder 11.
The guide post 13 extends upward from the outer periphery of the die holder 11 in the drawing. In the present embodiment, for example, four guide posts 13 (only two guide posts are shown in the figure) are provided.

The die part 12 is arranged on the upper surface of the die holder 11 inside the guide post 13 and is fixed to the die holder 11.
The die portion 12 is a metal member having a certain thickness, and a central portion is provided with a die hole 12a corresponding to the shape of the protrusion W1 formed by the protrusion forming device 1.
A plurality of guide holes 12b are provided outside the die hole 12a in the die part 12.

Inside the die hole 12a, a lower mold part 20 having substantially the same shape and the same size as the die hole 12a and determining the height of the protrusion W1 is arranged.
An upper end of a rod-shaped knockout member 21 for discharging the workpiece W is attached to a lower surface of the lower mold portion 20. The lower end of the knockout member 21 extends below the above-described through hole 11a provided in the die holder 11, and is connected to a drive mechanism (not shown). The drive mechanism presses the lower mold part 20 upward through the knockout member 21.

  The moving unit 30 includes a punch holder 31, a backing plate 32, a guide pin 36, and a punch unit 40.

The punch holder 31 is made of a thick plate member having substantially the same size as the die holder 11.
A first through hole 31 a is provided on the outer peripheral portion of the punch holder 31 at a position corresponding to the above-described guide post 13. A guide bush 31c is inserted and fixed in the first through hole 31a. The guide bush 31c is a cylindrical member and extends below the punch holder 31. The guide post 13 is inserted into the guide bush 31c, and the guide bush 31c moves along the outer periphery of the guide post 13, thereby ensuring a stable vertical movement of the moving unit 30 with respect to the fixed unit 10.

  A plurality of second through holes 31b are provided inside the guide bush 31c in the punch holder 31.

The backing plate 32 is mounted on the lower surface of the punch holder 31 inside the position where the guide bush 31c is provided.
In the backing plate 32, at a position corresponding to the above-described second through-hole 31b, a two-stage hole 33 that is continuous from the second through-hole 31b is provided.
The two-stage hole 33 has the same axis as the second through hole 31b, is continuous from the second through hole 31b, and has the same diameter as the first hole 33a and the second through hole 31b having the same diameter as the second through hole 31b. A second hole 33b having an axis and provided below the first hole 33a and having a smaller diameter than the first hole 33a is provided.

  The guide pin 36 is attached to the lower surface of the backing plate 32 on the outer peripheral side of the two-step hole 33, and extends downward of the backing plate 32.

The punch part 40 is fixed to the lower surface of the central part of the backing plate 32.
The punch section 40 includes a large punch section 41 on the backing plate 32 side and a small punch section 42 on the workpiece W side, which will be described in detail later.

The holding section 50 includes a bolt member 34, a holding plate 37, and a coil spring 35.
The bolt member 34 has a head portion 34a smaller than the diameter of the second through hole 31b and the first hole 33a and having a diameter smaller than the diameter of the second hole 33b. A portion 34b.
The bolt member 34 is inserted into the second through hole 31b, the first hole 33a, and the second hole 33b with the head portion 34a facing upward, and is screwed to the holding plate 37.

  The coil spring 35 is disposed at a portion of the bolt member 34 protruding from the backing plate 32 (the bolt member 34 is inserted into the coil spring 35).

The pressing plate 37 is arranged on the outer peripheral side of the punch section 40. The pressing plate 37 is a thick plate member, and has a first opening 37a formed at the center thereof. The first opening 37a has substantially the same diameter as the large punch 41 of the punch 40, and the large punch 41 has the first opening 37a. It is slidable within one opening 37a.
On the outer peripheral side of the first opening 37a on the upper surface of the holding plate 37, a bottomed bolt fixing screw portion 37b is provided. The screw portion 37b is provided at a position corresponding to the extending portion 34b of the bolt member 34, and the tip of the extending portion 34b is inserted and fixed to the screw portion 37b.
The coil spring 35 is disposed between the backing plate 32 and the pressing plate 37 on the outer periphery of the extending portion 34b.
A second opening 37c is provided at a position corresponding to the above-described guide pin 36 on the outer peripheral side of the first opening 37a of the holding plate 37. A guide pin 36 is inserted into the second opening 37c. The lower end of the guide pin 36 is further inserted into the guide hole 12b of the die part 12, and the guide pin 36 is guided straight by the guide hole 12b of the die part 12 and the second opening 37c.

  The workpiece W is arranged on the die 12. The workpiece W is, for example, a hot-rolled steel plate (SPFH590) for an automobile.

When forming a projection on the workpiece W, the workpiece W is arranged on the die 12. At this time, the positioning is performed so that the projection forming portion of the workpiece W is located on the die hole 12a.
At this point, the moving section 30 of the projection forming apparatus 1 is located above the state shown in FIG.
Next, the moving unit 30 is lowered by a drive mechanism (not shown), and the pressing plate 37 is brought into contact with the workpiece W.
Then, the moving section 30 is lowered, and the lower surface of the small punch section 42 of the punch section 40 is brought into contact with the workpiece W as shown in FIG.

Next, the moving unit 30 is further pressed downward by the driving mechanism. As a result, the punch section 40 further descends, and the small punch section 42 and the large punch section 41 press the workpiece W.
As shown in FIG. 1B, the workpiece W undergoes plastic deformation to form a projection W1 having a desired shape.
Thereafter, the moving section 30 is raised to separate the workpiece W from the small punch section 42 and the large punch section 41, and the lower mold section 20 is pushed up by the knockout member 21.
Then, the projection W1 of the workpiece W is pushed out from the die hole 12a, and the workpiece W can be taken out.

FIG. 3 is an enlarged view of a portion A in FIG. 1B after the protrusion W1 is formed. FIG. 4 is a partial cross-sectional view of the molded product W01 after the projection W1 is molded.
In the present embodiment, as shown in FIG. 3, the distance between the side surface of the small punch portion 42 and the side surface of the large punch portion 41 is d1, and the distance between the side surface of the small punch portion 42 and the inner surface of the die hole 12a is d2. Then
d2 <d1 (1)
There is a relationship.

In other words, the width S1 of the large punch portion 41, the width S2 of the small punch portion 42, and the width S3 of the die hole 12a in a predetermined cross section are
S2 <S3 <S1 (2)
There is a relationship.
(S1−S2) / 2 = d1, (S3−S2) / 2 = d2, and since S3 <S1 according to equation (2), d2 <d1 in equation (1).

In the present embodiment, the distance d2 between the side surface of the small punch portion 42 and the inner surface of the die hole 12a when inserted into the die hole 12a is smaller than the plate thickness T of the workpiece W.
T> d2 (3)

As shown in FIG. 4, when viewed as a molded product W01, the molded product W01 has a flat portion W2 having a thickness T and a thickness protruding downward in FIG. 4 from one surface A of the flat portion W2. A projection W1 of T and a rising portion P2 rising from the flat portion W2 to the projection W1 are provided.
The distance d2 between the side surface of the small punch portion 42 and the inner surface of the die hole 12a when inserted into the die hole 12a is the thickness d2 of the rising portion P2 in the direction orthogonal to the thickness T direction of the flat portion W2. However, as described above, T> d2 (3)
Satisfy the relationship.

The height H from one surface A of the flat portion W2 to one surface B of the protrusion W1 is larger than the thickness T of the workpiece W.
H ≧ T (4)
It is possible to satisfy the relationship

Further, the portion on the opposite side of the one surface B of the protrusion W1 is pressed by the punch portion 40, and thus is a concave portion. The concave portion is formed to have a first concave portion D1 having a first width S1 approximately equal to the width S1 of the large punch portion 41, and a second concave portion further concaved from the first concave portion D1 and having a width approximately equal to the width S2 of the small punch portion 42. A second recess D2 having a width S2. The width of the protrusion W1 on the one surface B side is equal to the width S3 of the die hole 12a, and as described above,
S2 <S3 <S1 (2)
Satisfy the relationship.

  Next, in order to easily understand the effects of the present embodiment, first, a comparative embodiment will be described. FIGS. 5A and 5B show a comparative example, in which FIG. 5A shows a state in which a workpiece W is arranged on a die part 12A of the comparative example, and FIG. W shows a state in which the protrusion W1 is formed.

The punch portion 40A of the comparative embodiment does not have a large punch portion as shown, but has only a small punch 42A.
In the comparative embodiment, the distance d2 between the side surface of the small punch portion 42 and the inner surface of the die hole 12a is equal to or less than the thickness T of the workpiece W.

In the comparative embodiment, when the punch portion 40A is lowered from the state of FIG. 5A, the punch portion 40A (small punch 42A) presses the workpiece W as shown in FIG.
When the indentation depth becomes deep, the workpiece W is plastically deformed. Here, since the workpiece W is deformed by shearing, the edge of the projection becomes sharp. However, a crack is generated because a tensile stress acts on a rising portion (P2 portion shown) of the protrusion.

However, the punch section 40 of the present embodiment has a two-stage structure of a large punch section 41 and a small punch section 42 as shown in FIG.
According to the present embodiment, the portion existing in the portion indicated by reference numeral B in FIG. 3 of the workpiece W is pressed downward by the large punch portion 41 when forming the projection W1. Then, the material of the part B flows to other parts as indicated by arrows in FIG. That is, the material is pressed and flows, and the material is supplied to a portion where the tensile stress acts, so that the tensile stress is reduced. In addition, when pressed by the large punch portion 41, the pressed portion is forged and the hardness increases.

FIG. 6 is a graph showing the results of measuring the hardness of the workpiece W formed in the present embodiment at the portions P1 to P4 in FIG.
In FIG. 6, the position shown by the dotted line is the hardness 197 HV of the workpiece W itself. According to the present embodiment, any part of P1 to P4 is hardened, and the product strength can be improved.

Further, in the present embodiment, since the protrusion W1 also has a deformed form due to shearing, the R of the corner of the workpiece W after the shaping becomes sharp (an angle sag hardly occurs). Therefore, fine irregularities can be formed.
The material flowing from the portion B not only increases the hardness but also flows to another portion of the workpiece W. Due to this flow, a predetermined thickness can be secured at the portions P2 and P3, which are the rising portions of the projection W1. Further, the flowed material is applied to a corner portion C1 between the large punch portion 41 and the small punch portion 42 and a corner portion C2 between the lower mold portion 20 and the side surface of the die hole 12a in the workpiece W. Since it is pushed in, the R of the corner of the workpiece W after the shaping becomes sharper (the angle sag is less likely to occur). Therefore, finer unevenness can be formed.

  According to the present embodiment, the edge of the projection W1 is sharpened as described above, so that the surface area of the portion of the projection W1 in contact with the die hole 12a is increased. For this reason, when rotating the workpiece W by bringing the protrusion W1 into contact with another member, a large rotational torque can be obtained. Therefore, it is suitable for manufacturing a projection such as a seat gear.

(2nd Embodiment)
FIG. 7 is a diagram showing a second embodiment of the present invention, and corresponds to FIG. 3 of the first embodiment. FIG. 8 is a partial cross-sectional view of a formed product W02 after processing in the second embodiment.
The present embodiment is different from the first embodiment in that the lower surface of the small punch portion 42 is provided with an inclined surface 42a inclined in a direction in which the thickness of the small punch portion 42 becomes thinner toward the edge of the small punch portion 42. It is a point that is.
The molded product W02 of the second embodiment is different from the molded product W01 of the first embodiment in that a slope W1a is formed on the bottom surface of the second recess D2 by the slope 42a of the small punch portion 42. . The other parts are the same and will not be described.

According to the present embodiment, since the slope 42a is provided when the punch portion 40 is pressed against the surface of the workpiece W, the material existing in the D portion of the workpiece W where the slope 42a is located is not shown in the figure. It is easy to flow in the direction shown by the arrow.
Therefore, the flow of the material to the portion P2 between the small punch portion 42 where cracks are easily generated and the inner surface of the die hole 12a is further promoted. Thereby, it is possible to form the protrusion W1 in which a crack (crack) is less likely to occur than in the first embodiment.

  Further, the flowed material flows to another portion of the workpiece W. The flowed material is pressed into the corner C1 between the large punch portion 41 and the small punch portion 42 and the corner C2 between the lower mold portion 20 and the side surface of the die hole 12a in the workpiece W. In addition, the corner R of the workpiece W (molded article W02) after molding becomes sharper. Therefore, finer unevenness can be formed.

  According to the present embodiment, the edge of the projection W1 is thus sharpened, so that the surface area of the portion of the projection W1 in contact with the die hole 12a is increased. For this reason, when rotating the workpiece W by bringing the protrusion W1 into contact with another member, a larger rotational torque can be obtained.

(Third embodiment)
In the third embodiment, after the projection W1 is formed on the workpiece W by the projection molding apparatus 1 of the second embodiment shown in FIG. 7, the projection molding apparatus 1 of the first embodiment shown in FIG. In this method, the workpiece W is further pressed to form the projection W1 more sharply.
According to the present embodiment, first, when the protrusion 40 is pressed against the surface of the workpiece W by the projection forming apparatus 1 of FIG. Allow it to flow outward.
Next, the edge portion can be sharpened by further flowing the material of the portion of FIG. 7 by the protrusion forming device 1 of FIG.

(Fourth embodiment)
FIG. 9 is a view showing a fourth embodiment of the present invention, and corresponds to FIG. 3 of the first embodiment. FIG. 10 is a partial cross-sectional view of a formed product W04 after processing in the fourth embodiment.
The difference between the punch part 40 of the projection forming apparatus 1 of the present embodiment and the first embodiment is that a projection 43 along the outer periphery of the small punch part 42 is provided at the end of the surface of the small punch part 42 on the workpiece W side. Is provided.
The difference between the molded product W04 of the fourth embodiment and the molded product W01 of the first embodiment is that, as shown in FIG. 10, the projection 43 forms a further concave portion W1b at the corner of the bottom surface of the second concave portion D2. That is the point. The other parts are the same and will not be described.

  According to the present embodiment, since the projections 43 are provided, the pressing load can be reduced as compared to pressing the entire lower surface of the punch portion 40 during molding.

According to the present embodiment, since the projections 43 are provided when the punch portion 40 is pressed against the surface of the workpiece W, the material existing in the E portion of the workpiece W where the projections 43 are located is removed. It easily flows in the direction indicated by the arrow in the figure.
Therefore, the flow of the material to the portion P2 between the small punch portion 42 where cracks are easily generated and the inner surface of the die hole 12a is further promoted. Thereby, it is possible to form the protrusion W1 in which a crack (crack) is less likely to occur than in the first embodiment.
The material that has flowed not only increases the hardness but also flows to other parts of the workpiece W. The flowed material is pressed into a corner C1 between the large punch portion 41 and the small punch portion 42 and a corner C2 between the lower mold portion 20 and the side surface of the die hole 12a in the workpiece W. In addition, the R at the corner of the workpiece W after forming becomes sharper. Therefore, finer unevenness can be formed.

  According to the present embodiment, the edge of the projection W1 is sharpened as described above, so that the surface area of the portion of the projection W1 in contact with the die hole 12a is increased. For this reason, when rotating the workpiece W by bringing the protrusion W1 into contact with another member, a larger rotational torque can be obtained.

Hereinafter, a result of forming the projection W1 on the workpiece W using the apparatus of the above-described embodiment will be described.
A load was applied to the protrusion forming device 1 using a knuckle press capable of applying a load of 400 tons maximum.
The workpiece W is a hot-rolled steel plate SPFH590, and has mechanical properties of YS (yield stress) of 522 MPa, TS (tensile strength) of 604 MPa, EL (elongation) of 26%, and a sheet thickness of 2.9 mm. 5 mm.
Table 1 below shows the measured values of the projection W1 of the workpiece W molded using the projection molding apparatus 1 of each embodiment.
(1) Height of projection (H), (2) Remaining thickness in width direction (distance d2 between side surface of small punch portion and inner surface of die hole), (3) Remaining thickness in thickness direction (4) 45 ° FIG. 3 shows which portions of the remaining thickness in the direction and the (5) corner portion are.

As described above, in the first embodiment, the second embodiment, the third embodiment, and the fourth embodiment, when the plate thickness of the workpiece W is 2.9 mm or 2.5 mm, (1) the protrusion height A protrusion W1 having a height H equal to or greater than the plate thickness T shown in the equation (4) (H ≧ T) could be formed.
Further, in the first, second, third, and fourth embodiments, when the thickness of the workpiece W is 2.9 mm or 2.5 mm, (2) the width direction remains. In the state where a predetermined thickness is secured within a range of not more than the plate thickness T of the workpiece W in the plate thickness d2, (3) remaining plate thickness in the plate thickness direction (4) remaining plate thickness in the 45 ° direction, the protrusion W1 is formed. Could be molded.
Further, in the third embodiment in which the protrusion W1 is formed based on the second embodiment, and then the protrusion W1 is formed based on the first embodiment, the corner portion becomes smaller and the protrusion is sharper. W1 was able to be formed.
Further, in the fourth embodiment in which the projection 43 is provided at the end of the surface of the small punch portion 42 on the side of the workpiece W, the corner portion becomes smaller and sharper than in the first and second embodiments. A protruding portion W1 could be formed.

DESCRIPTION OF SYMBOLS 1 Projection part forming apparatus 10 Fixed part 11 Dice holder 12 Dice part 12a Dice hole 30 Moving part 31 Punch holder 32 Backing plate 36 Guide pin 37 Press plate 40 Punch part 41 Large punch part 42 Small punch part 42a Slope 43 Projection

Claims (8)

A die portion provided with a die hole,
A large punch portion that is movable in the first direction toward the die portion side and cannot be inserted into the die hole, and protrudes from the large punch portion toward the die portion side and can be inserted into the die hole. And a punch portion having a small punch portion provided with a protrusion along the outer periphery at an end portion of the surface on the workpiece side,
By pressing a part of the workpiece disposed between the die part and the punch part toward the die part side by the punch part, the workpiece is deformed to form a projection,
Projection molding device. A distance d1 between a side surface of the small punch portion and a side surface of the large punch portion,
The distance d2 between the side surface of the small punch portion and the inner surface of the die hole is
d2 <d1
In the relationship
The projection forming apparatus according to claim 1. A distance d2 between a side surface of the small punch portion and an inner surface of the die hole;
The thickness T of the workpiece is
d2 <T
In the relationship
The projection forming apparatus according to claim 1. The lower surface of the small punch portion is provided with a slope inclined in a direction in which the thickness of the small punch portion becomes thinner toward the edge of the small punch portion,
The projection forming apparatus according to claim 1. A placing step of placing a workpiece on a die portion provided with a die hole,
A large punch portion having a size that cannot be inserted into the die hole, and projecting from the large punch portion toward the die portion side, and having an end capable of being inserted into the die hole and having a surface on the workpiece side, A punch portion having a small punch portion provided with a protrusion along an outer periphery is moved in a first direction toward the die portion side to move a punched workpiece disposed between the die portion and the punch portion. Pressing a portion to the die portion side by the punch portion, and deforming the workpiece to form a projection,
including,
Protrusion molding method. A distance d1 between a side surface of the small punch portion and a side surface of the large punch portion,
The distance d2 between the side surface of the small punch portion and the inner surface of the die hole is
d2 <d1
In the relationship
A method for forming a projection according to claim 5. A distance d2 between a side surface of the small punch portion and an inner surface of the die hole;
The thickness T of the workpiece is
d2 <T
In the relationship
The method of forming a projection according to claim 5. The punching step includes:
On the lower surface of the small punch portion, a projection portion is formed by a punch portion provided with a slope inclined in a direction in which the thickness of the small punch portion becomes thinner toward the edge of the small punch portion. Process and
A second step of forming a projection by a punch having a flat lower surface of the small punch;
including,
The method of forming a projection according to claim 5.