BR102012005013A2 - MATRIX ASSEMBLY, AND WORK PIECE MANUFACTURING METHOD THAT HAS OPENING AND STAGED PART - Google Patents

Abstract

MATRIX SET AND METHOD FOR MANUFACTURING A WORKING PIECE THAT HAS A STAGED PART AND AN OPENING. The invention relates to a matrix assembly (100) that is provided with a matrix (116) that has a concave part (115) and a matrix opening (117) in a matrix bottom (141) of the concave part ( 115); a hole punch punch (108); a flange forming punch (113) located outside the hole punch punch (108) and having a convex part (142), and a preceding punch (106) located inside the hole punch punch (108). A work piece (105) that has a stepped part (143) and an opening (125) is manufactured by moving the preceding punch (106) towards the die (116) to push the work piece (105), and moving the hole punch punch (108) in the direction of the die (116) to couple the hole punch punch (108) with the die opening (117), thereby forming the opening (125) at the bottom of the stepped part (143)

Description

Patent Descriptive Report for "MATRIX ASSEMBLY AND METHOD FOR MANUFACTURING A WORKING PART THAT HAS A STAGED PART AND AN OPENING".

BACKGROUND OF THE INVENTION FIELD OF THE INVENTION

The present invention relates to a die assembly and method for manufacturing a workpiece having a stepped portion and an opening. More specifically, the present invention relates to a die assembly and method for forming a stepped portion over a workpiece and punching an opening over a stepped lower portion.

RELATED TECHNIQUE

For example, in a vehicle manufacturing plant, when a component such as a fuel tank that has a large opening over a stepped bottom is formed, a die assembly is required to perform a process for forming a flange that It has a recessed step portion of a workpiece main body and a method for punching the opening at a predetermined position of the flange.

On JP-U-59-165725, a press machine for machining a

Inlay is described. In the press machine, a recessed head portion having a shallow stepped portion is formed, and then an opening is formed in a central portion of the recessed head portion.

In JP-A-2009-214151, a manufacturing method in which an opening is first formed and then a flange is formed is described. JP-A-2009-214151 also discloses that in a case where the opening is first formed, a forming pressure is not concentrated on the stepped portion even if a flange having a large stepped portion is formed by this prevents the staggered part from being cracked. However, according to the JP-U-59 press machine

165725, there is a problem that a deep stepped part cannot be formed as the stepped part can be cracked due to a workpiece stretch limit if the deep stepped part is formed in the main workpiece body. In order to avoid this problem, it is also possible to divide the above process into several steps. However, if the above process is divided into several steps in this way, the number of manufacturing processes increases and thus the overall operating efficiency is decreased. Also, due to an increase in the number of manufacturing processes, the times at which the workpiece is aligned also increase and thus the accuracy of the workpiece is degraded.

Meanwhile, according to the manufacturing method of JP-A-2009-214151, when the opening is first formed and then the flange is formed, a positional displacement and a geometrical displacement are corrected and thus it is difficult to form a aperture with a desired accuracy. SUMMARY OF THE INVENTION

One or more embodiments of the invention provide a die assembly and method of manufacture which are capable of forming a deep stepped portion over the workpiece main body and forming an opening in the deep stepped portion with high precision by a design. - single process.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 (a) is a view illustrating a workpiece formed

By a matrix assembly according to a first embodiment, Figure 1 (b) is a partial sectional view illustrating the matrix assembly according to the first embodiment.

Figures 2 (a) to 2 (e) are views illustrating a forming and punching process for manufacturing the workpiece according to the first embodiment.

Figures 3 (a) to 3 (c) are views illustrating the relationship between a preceding puncture flap and a punctured flap.

Figures 4 (a) to 4 (d) are views illustrating a stepwise punch.

and its modification.

Figure 5 (a) is a view illustrating a workpiece formed by a die assembly according to a second embodiment; Figure 5 (b) is a partial sectional view illustrating a die assembly according to a second embodiment. .

Figures 6 (a) to 6 (e) are views illustrating a forming and punching process for forming the workpiece according to the second embodiment.

DETAILED DESCRIPTION OF MODALITIES

Hereinafter, embodiments of the invention will be described with reference to the drawings. The embodiments described herein are not intended to limit the invention but merely exemplify the invention, and all features or combinations of features of the embodiments are not always essential to the invention. FIRST MODE

A first embodiment of the present invention will be described with reference to Figures 1 to 4. Figure 1 (a) is a view illustrating a workpiece.

formed by a matrix assembly 100 (Figure 1 (b)) according to the first embodiment.

The workpiece 105 formed includes a workpiece main body 129, a flange 130, and a peripheral workpiece part 145.

Flange 130 has a step portion 143 and a bottom 144 and an opening 125 is formed in the bottom 144.

Figure 1 (b) is a partial cross-sectional view illustrating matrix assembly 100 according to the first embodiment. Matrix assembly 100 includes an upper matrix 101 and a

lower die 102. Upper die 101 is driven to move in one direction toward and away from lower die 102 by a drive unit (not shown). Typically, as the upper die 101 is arranged on an upper side and the lower die 102 is arranged on a lower side, the upper die 101 is vertically driven. The upper die 101 includes an upper die clamp 103, a stepped punch 104, a step forming punch 110, an upper die block clamping 112, and a load source 122 for holding the step forming punch.

The stepped punch 104, the upper die blanking fastener 112 and the load source 122 are attached to the upper die hanger 103. The load source 122 is adapted to move the step forming punch 110 in one direction in the direction. steering and moving away from the upper die holder 103 using a spring, a gas cylinder and a hydraulic cylinder, etc.

The stepped punch 104 is composed of an approximately cylindrical punch punch 108 and a preceding punch 106. The preceding punch 106 has a smaller diameter than that of the punch punch 108 and projects from a front end. of the hole punch punch 108 towards the lower die 102 (which is referred to as a die 116 later). Further, the front end of the preceding punch 106 includes a lower surface 133 which is provided with a preceding punch edge 107 (preceding punch blade portion).

The hole punch punch 108 is provided with a hole punch punch edge 109 (blade portion) at its end towards the lower die 102 (which is referred to as die 116 later). The hole punch punch edge 109 is coupled with a die edge 119 (which will be described later) to form an opening 125 in workpiece 105.

Meanwhile, although the step punch 104 is integrally formed with the preceding punch 106 and the hole punch 108 in the above embodiment, the hollow cylindrical hole punch 108 may be concentrically arranged over a circumferential portion of the punch. That is, the preceding punch 106 and the hole punch punch 108 may be formed as separate members.

The step forming punch 110 includes a main body forming punch portion 111 and a flange forming punch 113. The flange forming punch 113 is provided at its front end with a convex portion 142. The portion main body forming punch 111 is coupled with a die main body portion 127 (which will be described later) to form a workpiece main body 129. The convex portion 142 of the master forming punch flange 113 is coupled with a concave die portion 115 (which will be described later) to form a flange 130 having a deep stepped portion over the main workpiece body 129.

Lower die 102 includes a lower die hanger 118, a die 116, and a load source 120 for holding a lower die block.

Load source 120 is adapted to move a lower die blanking fastener 114 in one direction toward and away from the lower die blanking 118 using a spring, gas cylinder and damping pin, etc.

The die 116 includes a die main body portion 127 which corresponds to the main body forming punch portion 111 of the step forming punch 110 and a concave die portion 115 which corresponds to the convex portion 142 of the punch of flange formation 113.

The concave die portion 115 includes an inner peripheral die surface 128 and a die bottom 141 within which a die opening 117 is formed. The inner peripheral matrix surface 128 and the matrix bottom 141 are formed to correspond to the shape of the convex portion 142.

The die opening 117 is provided with a die edge 109 at its end towards the upper die 101 (which is referred to the aforementioned hole punching punch 108). The die edge 109 is adapted to be coupled with the corresponding hole punch punch edge 109 to form aperture 125.

Hereinafter, reference is made to Figures 2 (a) to 2 (e) which illustrate a forming and punching process when the workpiece is formed according to this embodiment.

Figure 2 (a) illustrates a state where a workpiece 105 is disposed between the upper die 101 and the lower die 102 of the die assembly and the upper die 101 approaches the lower die 102.

At this time, the upper matrix blanking fastener 112

is first contacted at the peripheral workpiece part 145 (see Figure 1 (a)) of the workpiece 105 and the workpiece 105 is caught between the upper die blanking fastener 112 and the lower die blanking fastener 114 at a suitable upward pressure from the load source 120 to secure the lower die block.

Figure 2 (b) illustrates a state where the workpiece 105 is pressed by the preceding punch 106.

The upper die holder 103 moves towards the lower die holder 118, and at the same time the upper die block holder 112, the stepped punch 104 which is provided at its front end with the preceding punch 106, and the step-forming punch 110 moves toward the lower die holder 118. At this time, the step-forming punch 110 is moved toward the lower die holder through the load source 122.

In this case, as mentioned above, as the upper die blanking fastener 112 moves toward the lower die blanking fastener 114, the lower die blanking fastener 114 is retracted by the load source 120 while applying adequate pressure. in the peripheral workpiece part 145 of the workpiece 105.

When the preceding punch 106 moves toward die 116, the lower surface 133 of the preceding punch contacts workpiece 105 and peripheral workpiece part 145 of workpiece 105 is secured between the die block fastener. upper 112 and lower die blanking fastener 114 so that the workpiece is pressed by the concave portion 115 of die 116 to be stretched.

Fig. 2 (c) illustrates a state where a pilot hole 123 is formed on the workpiece 105 by the preceding punch edge 107.

As the upper die clamp 103 further moves towards the lower die clamp 118, the step forming punch moves towards the die 116. Consequently, the flange forming punch 113 (see Figure 1 (b)) of the step forming punch 110 and the concave portion 115 of the die 116 are partially coupled to form a portion of the flange 130 on the workpiece 105.

Here, when a flange part 130 is formed, a step portion of the workpiece is formed and fixed by the flange forming punch 113 and the concave portion 115. Accordingly, the workpiece is further stretched as shown. bottom surface 133 of the preceding puncture descends.

As the preceding punch 106 moves further in the direction of die 116, the workpiece 105 is cut by the preceding punch edge 107 of the lower surface 133 of the previous punch to form.

the pilot hole 123.

At this time, a movable distance of the stepped punch 104 towards the die 116 is suitably adjusted to cut the workpiece 105 which is in tension.

Figure 2 (d) illustrates a state where the workpiece main body 129 (see figure 1 (a)) and the workpiece flange 130 (see figure 1 (a)) are formed.

As the upper die holder 103 moves further toward the lower die holder 118, the step forming punch 110 moves toward the die 116 and the flange forming punch 113 and the concave portion 115 are coupled. with each other to form flange 130.

Further, a pressing pressure applied to the workpiece 105 by the step forming punch 110 is adjusted to a suitable range by the load source 122.

Figure 2 (e) illustrates a state where opening 125 of workpiece 105 is formed.

When the flange 130 is formed by the staggering forming punch 110, the staggering forming punch 110 stops in a state where applying a pressing pressure on the die 116 by the retraction of the load source 122, despite the fact that the fastener upper die 103 additionally moves towards lower die holder 118. Meanwhile the upper die holder 103 moves towards die 116, stepped punch 104 also moves toward die 116 and the punch punching edge 109 of the hole punching punch 108 of the stepped punch 104 is coupled with an edge 119 of the die to form the opening 125 in the bottom 144.

Now, when the upper die clamp 103 moves in the direction of the lower die clamp 118 and thus the upper die block clamp 112, the stepped punch having the preceding punch at its front end and the step forming punch. which is made to move through the load source 122 to move toward the lower die fastener 118, a method for forming a stepped portion over a workpiece will be described. Step 1:

One step for pushing the workpiece 105 into the

concave portion of die 115 (see Figure 2 (b))

The lower surface 133 of the preceding punch contacts the workpiece 105 and the peripheral workpiece part 145 of the workpiece 105 is secured between the upper die blanking fastener 112 and the lower die blanking fastener 114. Accordingly, the workpiece 105 is pushed into the concave portion 115 of the die 116 and stretched. Step 2:

A step for forming a portion of the stepped portion on the workpiece 105 (see Figure 2 (c))

Step forming punch 110 moves toward die 116 and flange forming punch 113 of step forming punch 110 and concave portion 115 of die 116 are partially coupled together to form a portion of the flange over workpiece 105. Step 3:

A step to form pilot hole 123 over the workpiece

105 (see paragraph 2 (c))

As the preceding punch 106 moves further in the direction of die 116, workpiece 105 is cut by the preceding punch edge 107 of the lower surface 133 of the previous punch to form a pilot hole 123. Step 4:

A Step for Forming Step Part 143 on Workpiece 105 (See Figure 2 (d))

The step forming punch 110 moves towards die 116 and the flange forming punch 113 and concave portion 115 of the die are coupled together to form flange 130. Step 5:

One step for punching the workpiece 105 (see figure

2 (e))

As staggered punch 104 moves toward the die

116, the hole punch punch edge 109 of the hole punch punch 108 of the step punch 104 is coupled with an edge 119 of the die to form the opening 125 in the bottom 144.

Next, referring to Figures 3 (a) to 3 (c), a behavior of workpiece 105 in the present embodiment will be explained by comparing a preceding punch flap 124 generated when forming pilot hole 123 by preceding punch 106 and a flap of hole punch punch 126 generated when forming aperture 125 by hole punch punch 108. Figure 3 (a) illustrates a state where pilot hole 123 is formed

above workpiece 105 and is a detailed view of figure 2 (c).

As the step forming punch 110 moves toward the die 116, the flange forming punch 113 and the concave portion 115 of the die are partially coupled to form a portion of the flange 130 (see Figure 1 (a)).

The flange forming punch 113 and the concave portion 115 of the die are coupled to secure the workpiece 105 when the pilot hole 123 is formed by the preceding punch edge 107 of the bottom surface 133 of the previous punch 106. And thus, the workpiece The working 105 is kept in tension and cut in the air without being supported by a corresponding portion of the die. Accordingly, the preceding punch flap 124 is not completely cut from workpiece 105, but partially connected to workpiece 105.

Figure 3 (b) illustrates a state where aperture 125 is formed on workpiece 105 by hole punching punch 108 and is a detailed view of figure 2 (e). As the hole punching punch 108 moves in the direction of

die 116 and the hole punching punch 109 and die edge 119 are coupled together, the opening 125 is formed on the bottom 144. At the same time, the punch punching flap hole drilling is occurred. Figure 3 (c) illustrates the comparison of the preceding puncture

tooth 124 and the hole punch punch flap 126.

The size of pilot hole 123 formed by the preceding punch flap 106 is the same as an outer circumference 146 of the preceding punch flap 124. However, the size of pilot hole 123 formed by forming the step portion of flange 130 and then forming the opening 125 is the same as an inner circumference 147 of the hole punching punch flap 126 and becomes larger.

As shown in Figure 3 (a), when a stepped portion is partially formed on the workpiece 105, a surrounding portion 149 around the pilot hole 123 of the workpiece 105 is wound around the flange forming punch 113 and pulled toward an inner peripheral surface 128 of the die, i.e. outward in a radial direction as the flange forming punch 113 moves toward the die 116. As shown in Figure 3 (b) in one step where formation of the stepped portion is complete, the surrounding portion 149 around the pilot hole 123 is formed in a shape that corresponds to the matrix bottom 141 and the inner peripheral surface of matrix 128. At this time, the part a work 105 (its surrounding portion 149) is punctured to form pilot hole 123 which is the same size as the outer circumference 146 of the preceding punch flap 124. The pilot hole expands toward the surface. 128 inner peripheral CIE matrix. As a result, with the expansion of pilot hole size 123, the stepped portion of workpiece 105 may be formed without interruption of its stretching.

Here, considering a case where pilot hole 123 is not formed, the part of the workpiece corresponding to the surrounding portion 149 of pilot hole 123 in a case where pilot hole 123 is formed is pulled toward the inner peripheral surface. 128 of the die as the flange forming punch 113 moves towards the die 116. However, in this case, due to the presence of the workpiece part corresponding to pilot hole 123, the movement of the workpiece part towards the of the internal peripheral surface 128 of the matrix is interrupted. Accordingly, there is a risk that the step portion 143 will become twisted and cracked.

In this embodiment, pilot hole 123 is formed prior to the formation of flange 130. Accordingly, movement of the surrounding portion 149 of pilot hole 123 is not interrupted and thus it is possible to prevent the step portion 143 from being twisted and cracked. Furthermore, the preceding puncture flap 124 is partially

connected to the hole punch punch flap 126. Accordingly, it is possible to prevent the preceding punch flap 124 and the hole punch punch flap 126 from being dispersed.

Figures 4 (a) to 4 (d) illustrate stepped punch 104 and a modification thereof.

The preceding punch 106 shown in Figure 4 (a) has a flat bottom surface 133 which is provided at its end (surrounding part) with an edge (preceding punch edge 107). The preceding punch edge is configured to form a circular pilot hole 123. In this embodiment, the shape of the preceding punch 126 may be varied and varied. Figures 4 (b) to 4 (d), respectively, illustrate the preceding punches 106b, 106c and 106d as a modification of the preceding punch 126.

Figure 4 (b) illustrates the preceding punch 106b. The preceding punch 106b has a circular section and an inclined bottom surface 133b. The inclined lower surface is provided at its front end with a preceding puncture edge 107b.

Figure 4 (c) illustrates the preceding punch 106c. The preceding punch 106c has a circular section and a tapered bottom surface 133c. The sloped bottom surface is provided at its front end with a preceding punch edge 107c. Figure 4 (d) illustrates the preceding punch 106d. The puncture required

The sender 106d has a circular section and a lower surface 133d which is composed of two planes. The sloped bottom surface is provided at its front end with a preceding punch edge 107d.

Although all of the preceding punches 106, 106b, 106c and 106d have a circular section as shown in Figures 4 (a) to 4 (d), the present invention is not limited to this. For example, the preceding punches 106, 106b, 106c and 106d may have another section shape such as a square and a triangle.

Similarly, the lower surfaces 133, 133b, 133c and 133d of the preceding punch are not limited to the circular shape. For example, in a case where the preceding punches 106, 106b, 106c and 106d have a rectangular section, the bottom surface shape may be a four-sided pyramid.

Further, in a case where the preceding punches 106, 106b, 106c and 106d have a triangular section, the bottom surface shape may be a triangular pyramid. SECOND MODE

A second embodiment of the present invention will be explained with reference to Figures 5 (a) to 6 (e).

Fig. 5 (a) is a view illustrating a workpiece 205 which is formed by a die assembly according to the second embodiment.

The formed workpiece 205 is formed as a polygonal shape having linear and curved portions and includes a main workpiece body 229, a flange 230 and a peripheral workpiece part 245.

Flange 230 has a step portion 243 and a bottom 244 and an opening 255 is formed in the bottom 244.

Figure 5 (b) is a partial cross-sectional view illustrating matrix assembly 200 according to the second embodiment. Matrix assembly 200 includes an upper matrix 201 and a

lower matrix 202.

Upper die 201 is driven to move in one direction towards and away from lower die 202 by a drive unit (not shown). Typically, as the upper die 201 is arranged on an upper side and the lower die 202 is arranged on a lower side, the upper die 201 is vertically driven. Upper die 201 includes an upper die holder 203, a stepped punch 204, a main body forming die 211, a flange forming die 213, an upper die block gripper 212, a load source 239 for securing the main body forming punch and a load source 240 for securing the flange forming punch.

Stepped punch 204, upper die blanking fastener 212, load source 239 and load source 240 are attached to upper die clamp 203. Load source 239 is adapted to move the die punch.

forming main body 211 in one direction toward and away from upper die holder 203 by use of a spring, a gas cylinder and a hydraulic cylinder, etc. Load source 240 is adapted to move flange forming punch 213 in one direction toward and away from upper die holder 203 by use of a spring, a gas cylinder and a hydraulic cylinder, etc.

Charge source 239 and charge source 240 may be separated

controlled so that the main body forming punch 211 and flange forming punch 213 can be separately controlled and moved.

Here, a difference between the die assembly 100 according to the first embodiment and the die assembly 200 according to the second embodiment is as follows: the die assembly 100 has a configuration in which the punch portion main body forming die 111 and flange forming punch 113 are integrated as step forming forming punch 110 while die assembly 200 has a configuration in which main body forming punch 211 and Flange formations 213 are formed as a separate member and may be separately controlled.

Similar to the first embodiment, the stepped punch 204 is composed of an approximately cylindrical bore punching 208 and an approximately cylindrical preceding punch 206. The preceding punch 206 has a smaller diameter than that of the hole punch punch 208 and projects from a front edge of the hole punch punch 208 toward the lower die 202 (which is referred to as a die 216 thereafter). Further, the front end of the preceding punch 206 includes a lower surface 233 which is provided with a preceding punch edge 207 (preceding punch blade portion).

Similar to the first embodiment, the hole punch punch 208 is provided with a hole punch punch edge 209 (blade portion) at its end towards the lower die 202 (which is referred to as a die 216 thereafter). The hole punch punch edge 209 is coupled with a die edge 219 (which will be described later) to form an opening 205 in workpiece 205.

Meanwhile, although the stepped punch 204 is integrally formed with the preceding punch 206 and the hole punch punch 208 as in the first embodiment, a hollow cylindrical hole punch punch 208 may be concentrically disposed on a circumferential portion of the punch. preceding punch 206. That is, preceding punch 206 and hole punch punch 208 may be formed as a separate member. The flange forming punch 213 is provided at its end.

front edge with a convex part 242.

In this embodiment, the flange forming punch 213 and the convex portion 242 are formed in a polygonal shape having linear portions and curved portions which correspond to the linear portions and curved portions of the polygonal flange 230.

The main body forming punch part 211 is coupled with a die main body part 227 (which will be described later) to form a workpiece main body 229 (see Figure 5 (a)) . Convex portion 242 of flange forming punch 213 is coupled with a concave die portion 215 (which will be described later) to form a flange 230 (see Figure 5 (a)) which has a deep stepped portion over the main body of workpiece 229.

Lower die 202 includes a lower die hanger 218, a die 216, and a load source for holding a lower die block.

The load source 220 is adapted to move a lower die blanking fastener 214 in one direction towards and away from the lower die blanking 218 using a spring, gas cylinder and damping pin, etc. The matrix 216 includes a matrix main body part 227 through

which corresponds to the main body forming punch portion 211 and a concave die portion 215 which corresponds to the convex portion 242 of the flange forming punch 213.

The concave die portion 215 includes an inner peripheral die surface 228 and a die bottom 241 within which a die opening 217 is formed. The inner peripheral matrix surface 228 and the matrix bottom 241 are formed to correspond to the shape of the convex portion 242.

Accordingly, the concave die portion 215 and the inner peripheral surface of the die 228 are also formed into a polygonal shape having linear portions and curved portions. The die opening 217 is provided with a matrix edge

209 at its end towards the upper die 201 (which is referred to the aforementioned hole punching punch 208). The die edge 209 is adapted to be coupled with the corresponding hole punch punch edge 209 to form the opening 225. Hereinafter, a process for forming the flange 230 using

The matrix set 200 will be explained.

Reference is made to Figures 6 (a) to 6 (e) which illustrate a forming and punching process when the workpiece 205 is formed according to this embodiment. Figure 6 (a) illustrates a state where a workpiece 205

is disposed between upper die 201 and lower die 202 of die assembly 200 and upper die 201 approaches lower die 202.

At this time, the upper die blanking fastener 212 is contacted with the peripheral workpiece part 245 of the workpiece 205 and the workpiece 205 is caught between the upper die blanking fastener 212 and the lower die block 214 with a suitable upward pressure from load source 220 to secure the lower die block.

Figure 6 (b) illustrates a state where the main body forming punch part 211 and die 216 hold workpiece 205 to form workpiece main body 229.

Upper die holder 203 moves towards lower die holder 218, and at the same time upper die block holder 212, stepped punch 204 which is provided at its front end with the preceding punch 206, a main body forming punch part 211, and flange forming punch 213 moves towards lower die holder 218. At this time, main body forming punch part 211 is moved toward the die holder Lower through the load source 239 to secure the main body forming punch portion and the flange forming punch 213 is moved toward the lower die clamp through the load source 240 to secure the flange forming punch.

At this time, as the upper die blanking fastener 212 moves toward the lower die blanking fastener 218, the lower die blanking fastener 214 is retracted by load source 220 while applying proper pressure to workpiece 205.

By doing so, the peripheral workpiece part 245 of the workpiece 205 moves toward the lower die holder 218 and is formed while being secured between the upper die holder blank 212 and the die holder blank holder. lower die 214. Further, the load source 249 for holding the forming punch

Main body forming punch is stretched to move main body forming punch 211 towards die 216. By doing this, main body forming punch 211 and die main body portion 227 are coupled with one another to securing and forming the workpiece main body 229. At this time, the main body forming punch 211 applies adequate pressure on the workpiece main body 229 by the load source 239 to form the main body. of workpiece 229.

At this time, when flange 230 is formed which has a polygonal stepped portion composed of linear portions and curved portions, a fluctuation may have occurred in a working part portion extending outwardly from the curved portion of the main part body. working 229 out. Accordingly, the workpiece main body 229 is secure and formed before flotation has occurred. In this way, fluctuation in the workpiece main body 229 may be prevented and a wrinkle due to fluctuation may also be prevented. Figure 6 (c) illustrates a state where the preceding punch 206

pushes and stretches workpiece 205 to cut the previous punch edge 207.

As the upper die clamp 203 further moves towards the lower die clamp 218, the preceding punch 206 moves towards the die 216. As the workpiece main body 229 (see Figure 5 (a)) is formed and held by the main body forming punch 211 and the die main body portion 227, the lower surface 233 of the front end of the preceding punch 206 contacts the workpiece 205 disposed in the concave portion 215 of the die 216 to push and stretch workpiece 205 toward the die. Further, as the preceding punch 206 moves toward die 216, the preceding punch edge 207 of the front end of the preceding punch 206 cuts workpiece 205 to form pilot hole 223.

Figure 6 (d) illustrates a state where the flange 230 having a deep recessed step portion of the workpiece main body 229 is formed.

As the load source 240 for holding the flange forming punch is stretched, the flange forming punch 213 moves towards the die 216. Doing so the flange forming punch 213 and the concave portion 215 are coupled together to form flange 230. At this time, a pressing pressure applied to flange 230 by flange forming punch 213 may be adjusted within a suitable range by load source 240.

Figure 6 (e) illustrates a state where aperture 225 of the workpiece

work 205 is formed.

When the flange forming punch 213 and the concave portion are coupled together to form the flange 230 the flange forming punch 213 and the main body forming punch 211 stop in a state where applying a pressure of pressing on the die 216 by retracting the load source 240 and the load source 239, although the upper die holder 203 additionally moves towards the lower die holder 218. Meanwhile as the upper die holder 203 moves in the In the direction of die 216, stepped punch 204 also moves toward die 216 and the hole punching edge 109 of hole punching punch 108 of stepped punch 204 is coupled with a die edge 219 to form opening 225 (see Figure 5 (a)) at bottom 244 (see Figure 5 (a)).

Thus, although the die assembly 200 forms the polygonal flange 230 which has a deep stepped portion and is composed of linear portions and curved portions, the fluctuation of the workpiece body 229 may be prevented and a wrinkle due to fluctuation may occur. also be prevented. Accordingly, as shown in Figure 5 (a), it is possible to form polygonal flange 230 which has a deep stepped portion and is composed of linear portions and wrinkle free curved portions.

Meanwhile1 although workpiece 205 includes a polygonal flange 230 composed of linear portions and curved portions in the above embodiment, it is also possible to form a circular flange as in the first embodiment.

Now, when the upper die holder 203 moves in the direction of the lower die holder 218 and thus the upper die block holder 212, the stepped punch 204 having the preceding punch 106 at its front end, the portion main body forming punch 211 which is moved through the load source 239 and flange forming punch 213 which is moved through the load source 240 moves toward the lower die holder 118, a method - to form a staggered part on a workpiece will be described. Step 1:

A step for forming the workpiece main body 229 (see Figure 6 (b))

The peripheral workpiece part 245 of workpiece 205 moves toward the lower die holder 218 and is formed while being secured between the upper die holder fastener 212 and the lower die holder fastener 214.

Further, as the main body forming punch portion 211 moves toward die 216, the main body forming punch portion 211 and the main die body portion 227 are coupled together to form the main body of workpiece Step 2:

A step for pushing the workpiece 204 into the concave die portion 215 and drawing (see Figure 6 (c))

When the preceding punch 206 moves towards die 216, the workpiece main body 229 (see Figure 5 (a)) is held by the main body forming punch part 211 and the die main body part 227. Accordingly, the lower surface 233 of the preceding punch 206 contacts the lower surface 233 of the front end of the preceding punch 206 contacts the workpiece 205 disposed in the concave portion 215 of the die 216 to push the workpiece 205 into the diaphragm. matrix and stretch the workpiece. Step 3:

A step to form pilot hole 223 over the workpiece

205 (see figure 6 (c))

As the preceding punch 206 moves further in the direction of die 216, workpiece 205 is cut by the preceding punch edge 207 of the front end of the preceding punch 206 to form a pilot hole 223. Step 4:

A step to form stepped portion 243 on the workpiece

work 205 (see figure 6 (d))

As flange forming punch 213 moves toward die 216, flange forming punch 213 and concave portion 215 of the die are coupled together to form flange 230. Step 5:

One step for punching the workpiece 205 (see figure

6 (e))

As staggered punch 204 moves toward the die

216, the hole punching punch edge 209 of the hole punch punching 208 of the stepped punch 204 is coupled with an edge 219 of the die to form the opening 225 (see figure 5 (a)) at bottom 244 (see Figure 5 (a)).

In accordance with the exemplary embodiments described above, a

Array set 100, 200 can include:

a die 116, 216 including a concave portion 115, 215 and a die opening 117, 217 in a die bottom 141, 241 of the concave portion 115, 215;

a hole punching punch 108, 208 arranged to

correspond with die opening 117, 217 and adapted to mate with die opening 117, 217 to perform a punching process on workpiece 105, 205;

a flange forming punch 113, 213 located outside the

hole punching punch 108, 208 and including a convex portion 142, 242 arranged to correspond with the concave portion 115, 215; and

a preceding punch 106, 206 located within the hole punch punch 108, 208 and projecting toward the die 116, 216 of the hole punch punch 108, 208.

The array array 100, 200 may be adapted to

that the preceding punch 106, 206 pushes the workpiece 105, 205 into the concave part 115, 215 and the convex part 142, 242 is coupled with the concave part 115, 215 to form the stepped part 143, 243 on workpiece 105, 205, prior to punching punch

108, 208 perform the punching process on the workpiece 105, 205.

Further, according to the exemplary embodiments described above, a method for manufacturing a workpiece 105, 205 may include:

a step of providing a die assembly 100, 200 which includes a die 116, 216 which has a concave portion 115, 215 and a die opening 117, 217 in a die bottom 141, 241 of the concave portion 115, 215; a hole punching punch 108, 208 arranged to match the die opening 117, 217; a flange forming punch 113, 213 located outside the hole punch punch 108, 208 and having a convex portion 142, 242, and a preceding punch 106, 206 located within the hole punch punch 108, 208;

a step of moving the preceding punch 106, 206 toward die 116, 216 to push the workpiece 105, 205 into the concave portion 115, 215;

a step of moving the flange forming punch 113, 213 towards die 116, 216 to cause the convex portion 142, 242 to be coupled to the concave portion 115, 215 thereby forming the stepped portion 143. 243 on workpiece 105, 205; and

a step of moving the hole punching punch 108, 208 towards die 116, 216 to couple the hole punching punch 108, 208 with die opening 117, 217 thereby forming the opening 125, 225 in. a bottom of the stepped portion 143, 243.

According to the above die assembly 100, 200 and the method, as the preceding punch 106, 206 is formed the pilot hole 123, 223 on the workpiece 105, 205 before the convex portion 142, 242 is acted upon. - joke with the concave part 115, 215 to form the stepped part 143, 243 on the workpiece 105, 205, the pilot hole 123, 223 is expanded upon formation of the stepped part 143, 243 and thus it is possible to prevent that the stepped portion 143, 243 is cracked without interrupting the stretching of the workpiece 105, 205. Still, after forming the stepped portion 143, 243, the workpiece

105, 205 is subjected to a punching process by the hole punching punch 108, 208 and thus a high precision punching process can be performed.

Moreover, as a series of operations mentioned above can be performed in a single process, it is possible to improve the operating efficiency.

In matrix set 100, 200 above, the preceding punch

106, 206 may include a blade portion 107, 207 which is adapted to form a pilot bore 123, 223 on the workpiece 105, 205 when the workpiece 105, 205 is pushed into the concave part 115. 215 by the preceding punch 106, 206. According to die assembly 100, 200 above, as the

As pilot 123, 223 can be formed on workpiece 105, 205 by the preceding punch 106, 206 having blade portion 107, 207 at its front end, it is possible to safely prevent the stepped portion from being cracked. without interrupting the stretching of the workpiece 105, 205 when the stepped portion 143, 243 is formed.

Further, even if a polygonal flange 230 having straight and curved portions is formed, the workpiece main body 229 is secured and formed by the main body forming punch 211 and the die 216 before the flange 230 be formed by the flange forming punch 213 and the concave die portion 215 (see figure 5 (b)). Accordingly, it is possible to process the main workpiece body 229 while preventing a wrinkle from occurring.

However, the present invention is not limited to the above embodiments, but may be varied without departing from the spirit of the present invention.

For example, pilot hole 123, 223 is formed in workpiece 105, 205 in the above embodiment. However, this is not essential in order to achieve an effect that the stepped portion 143, 243 can be prevented from cracking without interrupting the stretching of the workpiece 105, 205. Specifically, in the method for forming the stepped portion in the step. work, step S3 above is not essential. For example, even if step S3 is omitted, step S2 causes the preceding punch to push the part

I working into the concave part before the convex part of the step forming punch is coupled with the concave part of the die to form the step. Consequently, the workpiece has a margin by the distance at which the workpiece is pushed during the step formation. As a result, it is possible to obtain the above effect.

Specifically, performing step S3 after step S2 is performed as in the above embodiment, the above effect becomes more significant.

Claims (3)

1. Die assembly (100, 200) to form a scaled portion (143, 243) by punching an opening (125, 225) into a workpiece (105, 205), die assembly (100, 200) characterized in that it comprises: a die (116, 216) including a concave portion (115, 215) and a die opening (117, 217) in a die bottom (141, 241) from the end. concave (115, 215); a hole punching punch (108, 208) arranged to correspond with the die opening (117, 217) and adapted to mate with the die opening (117, 217) to perform a punching process on the workpiece. work (105, 205); a flange forming punch (113, 213) located outside the hole punch punch (108, 208) and including a convex portion (142, 242) arranged to correspond with the concave portion (115, 215); and a preceding punch (106, 206) located within the hole punch punch (108, 208) and projecting toward the die (116,216) of the hole punch punch (108, 208), wherein the die assembly ( 100, 200) is adapted such that the preceding punch (106, 206) pushes the workpiece (105, 205) into the concave part (115, 215) and the convex part (142, 242) is coupled with the concave part (115, 215) to form the stepped part (143, 243) on the workpiece (105, 205), prior to the hole punching punch (108, 208) to perform the punching process on the workpiece. to work (105, 205). A die assembly according to claim 1, characterized in that the preceding punch (106, 206) includes a blade portion (107, 207) which is adapted to form a pilot hole (123, 223) over the workpiece (105, 205) when the workpiece (105, 205) is pushed into the concave part (115, 215) by the preceding punch (106,206). Method for manufacturing a workpiece (105, 205) which has a stepped portion (143, 243) and an opening (125, 225) using a die assembly (100, 200), characterized in that it includes: a die (116, 216) having a concave portion (115, 215) and a die opening (117, 217) in a die bottom (141, 241) of the concave portion (115, 215); a hole punching punch (108,208) arranged to correspond with the die opening (117, 217); a flange forming punch (113, 213) located outside the hole punch punch (108, 208) and having a convex portion (142, 242), and a preceding punch (106, 206) located within the hole punching punch (108, 208), the method comprising the steps of: moving the preceding punch (106, 206) towards the die (116, 216) to push the workpiece (105, 205) to within the concave part (115, 215); moving the flange forming punch (113, 213) towards the die (116, 216) to cause the convex portion (142, 242) to be coupled to the concave portion (115, 215) thereby. forming the staggered part (143, 243) on the workpiece (105, 205); and moving the hole punching punch (108, 208) towards the die (116, 216) to couple the hole punching punch (108, 208) with the die opening (117, 217) thereby forming it. the aperture (125, 225) in a bottom of the stepped portion (143, 243).