JP3130706B2 - Molding method of thin web member - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a thin-walled web member, and more particularly, to a thin-walled sloping rib or a thin-walled rib having a large height-to-thickness ratio, which is greatly inclined from a web surface by press die forging. The present invention relates to a method for forming a thin-walled web member for forming a thin-walled web member having a shape into a net shape.

[0002]

2. Description of the Related Art In recent years, a web member used as a hinge of an opening / closing portion of an aircraft or a vehicle, that is, a web member having a plate-like rib largely protruding from a base plate-like web surface serving as a base has been required to have high reliability. From the surface, a material integrally formed by press die forging or the like is adopted, and a material having a thinner thickness and a higher specific strength is required for weight reduction. In general, in order to integrally form these web members into a net shape by press die forging, a method of forming ribs by a type of backward extrusion in which a part of the material to be formed is flowed in a direction opposite to the rolling direction is adopted. Have been.

However, in the case of a thin-walled web member having inclined ribs projecting obliquely from the web surface, the ribs are inclined with respect to the rolling direction in which the web is formed.
Normal press die forging cannot be formed into a net shape, and requires subsequent machining to finish the web. Further, in a thin web member having a thin rib having a large height ratio with respect to the thickness, it is necessary to apply a very large rolling force to the material to form the thin rib into a desired height by backward extrusion. There is a limit to the molding height due to the surface pressure resistance of the mold and the workability of the material to be molded (depending on the characteristics of the target material, for example, in the case of pure Ti material, for example, the rib height / rib width is usually The limit of the ratio is about 8 and the Al material usually has about 15).

[0004]

Accordingly, in order to form such a thin web member into a net shape, a material for forming ribs is extruded backward by applying pressure to a base web. It is necessary to apply pressure from both lateral directions to the material to reduce the thickness. That is,
The forming requires a reduction in the vertical (up and down) direction and a horizontal (both sides) direction, and in order to achieve this, a press device equipped with a mechanism for pressing in the horizontal direction in addition to a mechanism for pressing in the vertical direction Or a press device having a function capable of converting vertical pressurization into lateral pressurization by a wedge mechanism provided on a pressurizing head, such as that known as an RR forging device. It is possible.

However, in the former press apparatus, the external dimensions of the housing provided with the vertical and horizontal pressing mechanisms are large, and the structure is complicated and expensive. On the other hand, the latter press device only needs to have a vertical pressurizing mechanism, and since the molding die can be integrated in the form of a die set, the molding of a relatively thick web member is already performed. Has been applied. But,
In order to press-mold a thinner web member using this latter press device, a sound net-shaped molded product must be formed unless both the vertical and horizontal presses specified by the wedge mechanism are properly controlled. Cannot be obtained, and the appropriate pressurizing method has not been elucidated yet, and the method has not been applied to the molding of a thin-walled web member targeted by the present invention. In other words, there is no conventional technology that can effectively respond to the above-mentioned demands practically, and it is necessary to develop a new molding method capable of efficiently forming these thin web members into a net shape by press die forging. Was.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and uses a press device having a wedge mechanism in a pressurizing head, and uses a thin-walled slanted rib slantingly protruding from a web surface or a height relative to a thickness. It is an object of the present invention to provide a method for forming a thin web member capable of efficiently forming a thin web member having thin ribs having a large ratio into a net shape.

[0007]

According to the present invention, there is provided a method for forming a thin web member, comprising: a pair of split upper molds each having a rib forming surface portion on an opposing surface; Using a press device equipped with a wedge mechanism for the pressurizing head, the pair of split upper dies is pressed closer to each other by relative pressure on the lower anvil of the pressurizing head, and the pair of split upper dies is placed on the anvil. In forming a thin-walled web member having a thin-walled rib protruding from a plate-shaped web surface by lowering relative pressure with respect to the lower mold, the following technical measures were taken in order to achieve the above object. It is characterized by the following.

That is, in the first invention, the pressing approach of the pair of divided upper molds and the pressing of the lower mold are simultaneously performed,
And the first step of completing the pressing of the web portion by increasing the amount of reduction with respect to the lower mold than the amount of pressing and approaching of the paired upper molds, and performing only the pressing and approaching of the paired upper molds. The second step of completing the pressurization of the rib portion is continuously performed.

According to a second aspect of the present invention, the first step of performing only pressing on the lower mold of the pair of split upper molds, the pressing proximity of the pair of split upper molds, and the pressing of the lower mold are performed simultaneously. A second step of completing the pressurization of the web portion and a third step of completing the pressurization of the rib portion only by pressing and approaching the pair of divided upper dies are sequentially and sequentially performed. .

[0010]

According to the present invention, a press device having a pair of wedge mechanisms for a pair of split upper dies each having a rib forming surface portion on an opposing surface slidably on an inclined surface portion is used in a pressing head, Since the pair of split upper dies are pressed closer to each other by the relative pressure on the lower anvil of the pressurizing head, and the pair of split upper dies are lowered relative to the lower die placed on the anvil, By applying pressure in the vertical and horizontal directions to the material disposed on the lower mold, it can be pressure-formed into a thin-walled web member having thin-walled ribs that are inclined and protruded from the plate-shaped web surface.

Here, the problem of press-molding the thin-walled web member having the thin-walled ribs protruding greatly from the thin-walled web surface under the above-mentioned configuration is described as follows. Elucidate from a viewpoint.

Now, the forming procedure of the thin web member considered as a target will be described with reference to the graphs of FIGS. 5 and 6 which are explanatory diagrams of the forming procedure.
(r) forming step (hereinafter referred to as step R) and web section
It is disassembled into the molding step (w) (hereinafter referred to as step W) and examined. Here, the vertical pressing by lowering the lower die of the pair of split upper dies corresponds to the process W, and the horizontal pressing by the close proximity of pressing of the pair of split upper dies corresponds to the process R. Things.

First, as a simple molding procedure, FIG.
(a) As shown in the figure, considering a molding method in which the process W is continuously performed after the process R is completed, in the process W after the rib portion (r) is formed, the thickness of the rib portion (r) is increased. Since the _tr is small, the mold surface pressure for causing a metal flow from the web portion (w) to the rib portion (r) gradually increases to reach the allowable surface pressure of the mold, Since the mold is deformed or cracked, the pressure molding cannot be completed to the end. The state is shown by dotted lines (1R) and (1W) in the graph of FIG. In the graph, the point (Ms) indicates a blank shape, and the point (Mf) indicates a target final shape.

That is, in order to cause the metal flow to the rib portion (r), it is necessary to regulate the metal flow in the outer peripheral direction of the web portion (w), and to restrict the metal flow in the outer peripheral direction. On the other hand, in a state where the metal flow to the rib portion (r) is decreasing, the web portion (w)
When a large vertical pressure is applied to the mold, the allowable surface pressure of the mold is easily reached. On the other hand, the metal flow in the height direction at the rib (r) is not regulated until the molding is completed for the purpose, so if a large lateral pressure is applied, the rib (r) is reduced. As the thickness increases, it is possible to prevent the mold surface pressure from rising to near the final stage of the molding and to avoid reaching the allowable surface pressure.

Meanwhile, the web portion thickness t _w of the limit condition of the mold surface pressure, as indicated by the curve (p) in the graph of [6], pouring the material from the web portion (w) Rib
(r) becomes smaller as the thickness _tr increases, so that the process R can be performed only in a region where the limit web thickness is equal to or less than the final web thickness, that is, in a region where the forming force limit curve (p) is not reached. . Therefore, the molding force limit curve (p)
And the web thickness t _w cannot be reduced beyond
The rib thickness t _r at the initial step R set lower, followed by proceeding to step W halfway, to complete the further remaining step R,
Subsequently, a procedure for completing the remaining process W is required.

Here, a molding procedure generally used for molding a relatively thick web member, that is, a molding method in which steps W and R are simultaneously performed and pressure is applied until the final shape is obtained, will be considered. Then, the pressurization includes a longitudinal component force, and thus the same problem as described above occurs. In addition, this has been a major obstacle to press-molding the thin web member. The state is shown by a dotted line (2R-W) in the graph of FIG.

Next, as another simple forming procedure, as shown in FIG. 5 (b), after completing step W, step R
Considering a molding method that continuously performs the web portion (w)
In step W of molding a, since the ratio of the rib thickness t _r and the web portion thickness t _w gradually becomes larger, consists web portion to insufficient metal flow into the rib portion, the rib portion
A shrinkage defect occurs on the lower surface side of the base of (r), and pressure molding cannot be completed to the end. The state is shown by a dotted line (3W) in the graph of FIG.

Meanwhile, the web portion thickness t _w of the boundary conditions of the shrinkage defects, as indicated by the curve (m) in the graph of [6], ribs of pouring material from the web portion (w)
(r) becomes larger as the rib portion thickness _tr becomes smaller.
In the initial process W, it is possible to advance only to the limit web thickness, and thereafter, the process R and the process W are repeated along the limit condition of the shrinkage defect, that is, along the metal flow limit curve (m). Or at the same time.

Here, when the limiting conditions occurring in each of the above molding procedures are arranged and considered, first, the limiting condition of the die surface pressure becomes smaller as the rib portion thickness _tr becomes larger. Further, if only the step W (vertical pressing) is advanced, it is not possible to avoid reaching the mold allowable surface pressure. However, only the step R (lateral pressing) avoids the mold surface pressure by keeping it low. It is possible. On the other hand, the critical conditions for the shrinkage defect are the rib portion thickness _tr and the web portion thickness tr in the process W.
_This can be avoided if the ratio of _w is kept within a certain range. Therefore, between larger rib portion thickness t _r is the final thickness, to avoid the boundary conditions of the mold surface pressure and shrinkage defects, it is possible to thickness reduction of the web portion thickness t _w to the final thickness, also, after allowed thickness reduction of the web portion thickness t _w to the final thickness may thickness reduced the rib thickness t _r to a final thickness just step R for avoiding marginal conditions of the mold surface pressure, thus in the entire pressure course The molding of the target thin web member can be completed while avoiding the limit conditions of the mold surface pressure and the shrinkage defect.

That is, this will be described with reference to the graph of FIG. 6. From the point (Ms) in the graph, through a region divided by a dashed line, the forming force limit (P) and the metal flow limit (m) The process W and the process R are simultaneously or sequentially repeated in the range (V) where both are small and deviate from each other, thereby avoiding the limit conditions of the mold surface pressure and the shrinkage defect, and reducing the web part thickness _tw . Reduced to final thickness, followed by solid line (4
As shown in R), the remaining process R is performed, that is, by applying a lateral pressing force that is easy to suppress the increase in the mold surface pressure, and reducing the rib portion thickness _tr to the final thickness, thereby reducing the total thickness. In the pressing process, the molding can be completed while avoiding the limit conditions of the mold surface pressure and the shrinkage defect.

Considering the procedure of applying pressure from the point (Ms) representing the blank shape to the area (V) through the area divided by the dashed-dotted oblique line, the procedure in which the process R is prioritized, It is not advisable to narrow the part thickness _tr at an early stage. On the other hand, in the procedure in which the process W is advanced to just before the metal flow limit (m) and then the process R and the process W are performed along the limit curve, the division is divided. The vertical and horizontal pressurization control of the upper mold becomes complicated and not suitable for practical use.

Therefore, as a preferable procedure, one is to perform the steps R and W at the same time and to increase the amount of pressurization in the step W more than the step R, and to show a solid line (4W-R) in the graph. As shown, pressurization at a ratio from the (Ms) point to the (G) point which is substantially the center of the (V) range is performed, and while the rib part thickness _tr is large, the web part thickness _{tw is changed} to the final thickness. Method to reduce
One is that, as shown by the solid line (4'W) in the graph, the process W is preceded by a margin as viewed from the metal flow limit (m), and then the process R and the process W are performed simultaneously. ,
As shown by the solid line (4'WR) in the graph, performed pressure ratio towards become (G) point substantially at the center of (V) range, the web portion thicknesses between large rib portion thickness t _r This is a method of reducing _tw to the final thickness. And, following this, solid line (4R)
As shown by, by performing the remaining process R to reduce the rib portion thickness _tr to the final thickness, the molding is completed while avoiding the limit conditions of the mold surface pressure and the shrinkage defect in the entire pressing process. And the press control of the pair of split upper molds becomes easier.

Here, in the first invention, the pressing approach of the pair of divided upper dies and the pressing of the lower dies are performed simultaneously,
A first step (the above-described step W + step R) of completing the pressurization of the web portion by increasing the amount of reduction with respect to the lower mold than the amount of pressing approach between the pair of divided upper dies; The second step (the above step R) of completing the pressurization of the rib portion by only performing the pressing approach is continuously performed, so that the limit conditions of the mold surface pressure and the shrinkage defect are avoided in the entire press forming process. Therefore, the desired thin-walled web member can be efficiently formed into a net shape without causing mold deformation or shrinkage defect.

Further, in the second invention, the first step of performing only the pressing of the pair of divided upper dies against the lower die (the above-described step W).
And a second step (step W + step R) of simultaneously performing the pressing proximity of the pair of divided upper dies and the pressing of the lower mold to complete the pressing of the web portion, and the pair of divided upper dies. And the third step (the above-mentioned step R) of completing the pressurization of the rib portion by performing only the pressing approach of the mold is performed in succession. Thus, the desired thin-walled web member can be formed into a net shape and efficiently without causing mold deformation or shrinkage defects.

[0025]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a front sectional view showing a schematic configuration of a press device used for forming a thin web member according to an embodiment of the present invention.

The press device shown in FIG. 1 has a pair of wedges on a working portion of a press body (1) having a very general configuration having a main ram (2) at an upper portion and a knockout mechanism (not shown) at a lower portion. A pressure head (3) having mechanisms (4) and (4 '), and a lower anvil (3) connected to the pressure head (3) at intervals through a plurality of extendable connection rods (7). 6) and a pair of upper molds arranged between the pressure head (3) and the lower anvil (6).
(8), (8 ') and the lower mold (9) are arranged in the form of a die set.

Here, the pressure head (3) has inclined sliding surfaces (4a) and (4a ') which are arranged to face each other on both lower sides thereof, and which spread downwardly on their opposing surfaces. Provided wedge mechanism (4),
(4 '), and a pair of auxiliary cylinders (5), (5') with the output shaft directed downward are provided inside the pair of wedge mechanisms (4), (4 ').

The pair of split upper dies (8) and (8 ') are formed on the opposing surfaces thereof with forming surface portions (8a) and (8a') for forming inclined ribs of a thin web member to be formed. It is equipped with
Each outer surface is slidably engaged with the inclined sliding surfaces (4a) and (4a ') of the pair of wedge mechanisms (4) and (4'), and the upper surface is an auxiliary cylinder. The lower mold (9) is engaged and held slidably in the horizontal direction on the end face of the output shaft of (5), (5 ′).
Are arranged in pairs above.

The lower mold (9) is composed of a main pressure receiving mold (9a) having a flat outer contour conforming to the outer contour of the web of the thin web member to be molded, and a main pressure receiving mold (9a). A cylindrical outer edge defining mold (9b) which is fitted externally so as to be slidable in the vertical direction and has an enlarged diameter portion on the upper outer periphery, a main pressure receiving mold (9a) and an outer edge regulating mold (9b). A holding recess that holds from below and moves the outer edge regulating mold (9b) up and down a predetermined amount via a spring (10).
(9d) provided with a holding mold (9c). The holding mold (9c) is fixedly arranged on the lower anvil (6), while the main pressure receiving mold (9a) can be raised independently by the operation of a knockout mechanism (not shown). .

In this press apparatus, the pressurizing head (3) is lowered by the operation of the main ram (2) under the above arrangement, and the upper die (8), (8 '),
It can be pressed and approached in the horizontal direction close to each other, and can be synchronously lowered toward the lower mold (9).

As a first embodiment, a thin web member having thin inclined ribs projecting obliquely from a thin plate-shaped web surface serving as a base using the above-described press apparatus is an explanatory view of a forming procedure [FIG. Pressure molding was performed according to the procedure shown in 2].

First, as shown in FIG. 1, the lower mold (9)
The blank heated to the specified temperature on the main pressure receiving mold (9a)
(B) is charged. The blank (B) in this example is
Made of Ti alloy material, the outer contour of the plane is regulated to the outer edge (7b)
It is formed in such a shape that it can be inserted with a small gap into it, and is preformed in a vertical cross-sectional shape in which a central portion serving as a rib forming target portion is bulged upward.

As a first step, the pressing head (3) is lowered at a constant speed by the main ram (2) of the pressing device (1), while the pair of auxiliary cylinders (5) and (5 ') are operated. Then, as shown in FIG. 2 (a), this pressure head
The split upper die held by the wedge mechanisms (4) and (4 ') of (3)
(8) and (8 ') were pressed close to each other and lowered toward the lower mold (9).

At this time, the amount of reduction with respect to the lower mold (9) is made larger than the amount of pressing approach between the pair of divided upper dies (8) and (8 '), and the reduction with respect to the lower mold (9) is: This is performed until the enlarged diameter portion on the upper periphery of the outer edge defining mold (9b) of the lower mold (9) comes into contact with the upper surface of the holding mold (9c) and stops.
Was stopped at an intermediate stage of about 1.5 times the final thickness, while the web portion (w) was reduced to the final thickness.

Subsequently, as a second step, at the same time as the lowering of the outer edge defining mold (9b) of the lower mold (9) stops, the back pressure of the pair of auxiliary cylinders (5) and (5 ') is released, [ As shown in FIG. 2 (b), the pair of split upper dies (8) and (8 ') are stopped from rolling down against the lower die (9), while the pair of split upper dies (8) are stopped. , (8 ') are pressed close to each other to reduce the thickness of the rib (r) at the intermediate stage to the final thickness, and the pressure forming is completed, thereby obtaining a thin-walled web member having the desired shape.

In the present embodiment, which is formed by the above-described procedure, in the first step, the web portion (w) is transferred to the main pressure receiving mold (9a) defined by stopping the outer edge defining mold (9b). The pair of split upper molds (8), (8 ') are formed to a predetermined thickness by reduction, and the metal flow in the outer peripheral direction at the web portion (w) by the reduction is defined by an outer edge defining mold (9b). Specified by On the other hand, the thickness reduction of the rib (r) is stopped at an intermediate stage, that is, the opposing molding surfaces (8a), (8) of the pair of divided upper dies (8), (8 ')
Since the distance between a ') is still wide, the metal flow of the blank (B) due to the reduction flows toward the rib (r) with low resistance, and the pair of upper molds (8), The height is increased between the molding surface portions (8a) and (8a ') of (8'). Therefore, in the first step, the web portion (w) can be reduced to the final thickness while avoiding the limit condition of the mold surface pressure. Further, the pressing approach speed between the pair of divided upper dies (8) and (8 ') and the rolling speed with respect to the lower dies (9) may be set to a fixed ratio, and the operation control thereof is easy.

In the second step, the rib portion (r) is moved between the molding surface portions (8a) and (8a ') by the pressing approach of the pair of divided upper dies (8) and (8'). A metal flow is formed to a predetermined thickness by causing a metal flow obliquely upward along, but the material necessary for the molding is poured between the two by the first step, and the metal flow upward from its purpose is: Since the pressure is not regulated until the molding is completed, the thickness of the rib (r) is reduced by a relatively small pressing force, and the height is increased without causing a shrinkage defect. Therefore, in the second step, the limit condition of the mold surface pressure is avoided, and the rib portion is formed without causing shrinkage defects.
(r) can be reduced to the final thickness, so that the desired thin-walled web member can be pressure-formed into a net shape and as a good product without shrinkage defects.
In addition, through the first and second steps, the pressure head
(3) Pressing device (1)
Is easy to control, and the pressure molding can be performed efficiently.

Next, as a second embodiment, a thin web member having the same thin sloping rib as described above was pressure-formed by the above-described press apparatus in the procedure shown in FIG. did.

First, as in the first embodiment, a blank (B) made of a Ti alloy material heated to a predetermined temperature is placed in a lower mold (9).
Of the main pressure receiving mold (9a).

As a first step, the pressing head (3) is lowered at a constant speed by the main ram (2) of the pressing device (1), while the back of the pair of auxiliary cylinders (5) and (5 ') is pressed. The pressure is blocked and, as shown in FIG. 3 (a), the upper die (see FIG. 3 (a)) engaged with and held by the wedge mechanisms (4) and (4 ') of the pressure head (3). 8) and (8 ') were lowered toward the lower mold (9) to reduce the thickness of the web portion (w). At this time, a pair of split upper molds (8),
The interval between the opposing molding surfaces (8a) and (8a ') of (8') is the rib
(r) is set to about 2 to 2.5 times the final thickness, and the web (w)
Was stopped at an intermediate stage of about 50%.

Subsequently, as a second step, while the pressure of the pressurizing head (3) is continued, the pair of auxiliary cylinders (5) and (5 ') are operated, and FIG. As shown, a pair of split upper molds (8) and (8 ') are pressed close to each other, and a lower mold (9).
It was reduced toward. At this time, a pair of split upper molds (8),
(8 ') The amount of pressing approach between them and the amount of reduction to the lower mold (9) are made substantially equal, and the reduction to the lower mold (9) is
The enlarged diameter part on the upper periphery of the outer edge defining mold (9b) of (9) is the holding mold.
(9c) until it stops until it stops.In this way, the rib (r) is stopped at an intermediate stage of about 1.5 times the final thickness, while the web (w) is reduced to the final thickness. Was.

Subsequently, as a third step, at the same time as the lowering of the outer edge defining mold (9b) of the lower mold (9) stops, the back pressure of the pair of auxiliary cylinders (5) and (5 ') is released, [ As shown in FIG. 3 (c), the pair of split upper dies (8) and (8 ') are stopped from rolling down against the lower die (9), while the pair of split upper dies (8) are stopped. , (8 ') are pressed close to each other to reduce the thickness of the ribs (r) stopped at the intermediate stage to the final thickness, complete the pressure forming, and obtain a thin-walled web member of the desired shape. Was.

In the present embodiment, which is formed by the above procedure, in the first step, the web portion (w) is connected to the pair of split upper dies (8) and (8 ') to the main pressure receiving die (9a). The metal is formed into an intermediate stage thickness by the reduction and the metal flow in the outer peripheral direction at the web portion (w) by the reduction is defined by the outer edge defining mold (9b). On the other hand, the thickness of the rib portion (r), that is, the interval between the molding surface portions (8a) and (8a ') of the pair of divided upper molds (8) and (8') is set to a wide interval. The metal flow of the blank (B) due to the reduction flows toward the rib (r) having a low resistance, and the molding surfaces (8a) and (8a ') of the paired upper dies (8) and (8') Increase height between. Therefore, in the first step, while the thickness of the web portion (w) is reduced, a smooth metal flow to the rib portion (r) can be caused, and the limit condition of the shrinkage defect can be avoided. Further, the rolling speed of the paired upper dies (8) and (8 ') with respect to the lower die (9) may be equal to the rolling speed of the pressing head (3), and the operation control thereof is easy.

In the second step, the web portion (w) is
Main pressure receiving mold defined by the lower edge stop of outer edge defining mold (9b)
(9a) The pair of upper molds (8) and (8 ') are formed to a predetermined thickness by reduction, and the web part (w) is formed by the reduction.
The metal flow in the outer peripheral direction is defined by the outer edge defining mold (9b). On the other hand, since the thickness reduction of the rib (r) is stopped at the intermediate stage, that is, between the opposed forming surface portions (8a) and (8a ') of the pair of split upper molds (8) and (8'). Since the gap is still wide, the metal flow of the blank (B) due to the reduction flows toward the low resistance rib (r), and the pair of upper molds (8) and (8 ') The height is increased between the molding surface portions (8a) and (8a '). Therefore, in the second step, the web portion (w) can be reduced to the final thickness while avoiding the limit conditions of the mold surface pressure and the shrinkage defect. Further, the pressing approach speed between the pair of divided upper dies (8) and (8 ') and the rolling speed with respect to the lower dies (9) may be set to a fixed ratio, and the operation control thereof is easy.

In the third step, the rib portion (r) is moved between the molding surface portions (8a) and (8a ') by the pressing approach of the pair of divided upper dies (8) and (8'). The metal is formed into a predetermined thickness by causing a metal flow obliquely upward along the metal. The material required for the molding is poured between the two by the first and second steps, and the metal is formed upward from the purpose. Since the flow is not regulated until the molding is completed, the thickness of the rib (r) is reduced by a relatively small pressing force, and the height is increased without causing shrinkage defects. Therefore, in the third step, the rib (r) can be reduced to the final thickness without avoiding the limit condition of the mold surface pressure and without causing the shrinkage defect.
Thus, similarly to the first embodiment, the desired thin web member can be formed into a net shape and pressure-formed as a good product having no shrinkage defect. In addition, the above first to first
Through the third step, as in the first embodiment, the pressure head
(3) Pressing device (1)
Is easy to control, and the pressure molding can be performed efficiently.

In the above two embodiments, examples of forming a thin-walled web member having thin-walled inclined ribs projecting obliquely from a thin-plate-shaped web surface have been described. However, the method of the present invention does not tilt from the web surface. And a thin web member having a thin rib having a large height ratio with respect to the thickness, under a molding procedure similar to that of the above-described two embodiments,
Pressure molding can be performed efficiently as a good product having a net shape and no shrinkage defects.

In the above two embodiments, a press device having a main ram at the top was used. However, this is only one example, and in the method of the present invention, a vertical pressing force was provided to the pressing head. For example, as shown in FIG. 4, a fixed crosshead (13) is provided at an upper portion and a main ram is provided at a lower portion, as shown in FIG.
It goes without saying that a press device having a die set having the same configuration as that shown in FIG. 1 can be used in the working section of the press body (11) provided with (12).

[0048]

According to the method for forming a thin web member according to the present invention, a thin inclined rib or a height ratio of the thickness to the thin inclined rib projecting from a thin web surface is obtained by using a pressing device having a wedge mechanism. A thin web member having a large thin rib can be efficiently formed into a net shape.

[Brief description of the drawings]

FIG. 1 is a front sectional view showing a schematic configuration of a press device used for forming a thin web member according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram of a forming procedure of a thin web member according to the first embodiment of the present invention.

FIG. 3 is an explanatory view of a forming procedure of a thin web member according to a second embodiment of the present invention.

FIG. 4 is a front sectional view showing a schematic configuration of another pressing device used for molding the thin web member of the present invention.

FIG. 5 is a conceptual diagram for explaining a relationship between a molding procedure of a thin web member and a metal flow according to the present invention.

FIG. 6 is a graph for explaining a relationship between a molding procedure of a thin-walled web member according to the present invention, a die surface pressure, and a limit condition of a shrinkage defect.

[Explanation of symbols]

(1) --Pressing device, (2) --Main ram, (3) --Pressure head, (4), (4 ')-Wedge mechanism, (4a), (4a')-Tilt slide Moving surface,
(5), (5 ')-Auxiliary cylinder, (6)-Lower anvil, (7)-Connecting rod, (8), (8')-Split upper mold, (8a), (8a ')-Molding surface, (9)-lower die, (9a)-main pressure receiving die, (9b)-outer edge prescribed die, (9c)-holding die, (9d)- Retaining recess, (10)-spring,
(B)-Blank.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Satoru Sakae 1-5-5 Takatsukadai, Nishi-ku, Kobe-shi, Hyogo Kobe Steel, Ltd. Kobe Research Institute (72) Inventor Nobuo Kanamaru Nishi-ku, Kobe-shi, Hyogo 1-5-5 Takatsukadai Kobe Steel, Ltd. Kobe Research Institute (56) References JP-A 1-233034 (JP, A) JP-A 4-55034 (JP, A) (58) Survey Field (Int.Cl. ⁷ , DB name) B21J 1/00-13/14 B21J 17/00-19/04 B21K 1/00-31/00

Claims (2)

(57) [Claims] 1. A press device having a pair of wedge mechanisms provided on a pressurizing head for holding a pair of split upper molds each having a rib forming surface portion on an opposing surface slidably on an inclined surface portion. The relative pressure of the pressure head to the lower anvil causes the pair of split upper dies to press and approach each other, and causes the pair of split upper dies to be pressed relative to the lower die placed on the anvil to form a plate-like shape. When molding a thin-walled web member having a thin rib protruding from the web surface, the pressing approach of the paired upper molds and the pressing down of the lower mold are performed simultaneously, and the pressing of the paired upper molds is performed. A first step of completing the pressing of the web portion by increasing the amount of reduction with respect to the lower mold than the approaching amount, and a second step of completing the pressing of the rib portion only by pressing and approaching the pair of divided upper molds. Characterized by performing the process continuously A method for forming a web member. 2. A press apparatus having a pair of wedge mechanisms provided on a pressure head for holding a pair of split upper molds each having a rib forming surface portion on an opposing surface slidably on an inclined surface portion. The relative pressure of the pressure head to the lower anvil causes the pair of split upper dies to press and approach each other, and causes the pair of split upper dies to be pressed relative to the lower die placed on the anvil to form a plate-like shape. In forming a thin web member having thin ribs protruding from the web surface, a first step of performing only pressing down on a lower mold of a pair of split upper dies, and pressing proximity of a pair of split upper dies A second step of simultaneously pressing the lower mold to complete the pressing of the web portion, and a third step of performing only pressing approach of the pair of divided upper dies to complete the pressing of the rib portion. Thin-walled webs characterized by being performed sequentially and sequentially The method of forming the member.