JP2006055860A - Method and structure for cooling punch in drawing/ironing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a punch structure which has a simple structure having no resinoid core in a ram portion to reduce the necessity of the maintenance, and can reduce the quantity of water and air for adjusting temperature, and can improve the cooling efficiency at the punch portion to make the high speed forming possible. <P>SOLUTION: The punch structure has a large air passage in its central portion, and has a ram composed of a monostructure having a large number of through-holes arranged in parallel with an axis of a water flow for adjusting temperature. Each axis of the through-holes of the punch structure are arranged symmetrically. Further, the punch structure has a through-hole as a cavity in addition to the passages for the water and air for adjusting temperature. A punch sleeve is provided with a belt-shape passage for the water for adjusting temperature so as to wind below the surface of the punch sleeve. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a cooling method and a punch cooling structure that suppresses a temperature rise due to processing heat generated by a punch used when a can is manufactured by drawing and ironing.

  In general, when manufacturing metal cans such as canned beer and soft drinks, first the metal can be drawn to form a drawn can, and then the drawn can is ironed to a predetermined shape A method of forming a metal can having a thickness is employed. In this ironing process, the squeezed can is put on the tip of the punch, and it is carried by the stroke of the punch through a plurality of dies arranged so that the opening diameter is gradually reduced, and is squeezed each time it is sequentially passed. The thickness of the body wall will be reduced.

  Patent Document 1 discloses a process for forming a can body using a molding apparatus for a bottomed thin can body. In the molding process, first, a round blank of malleable metal is formed into a cup-shaped molded product X comprising a can bottom forming part Y and a cylindrical can body forming part Z connected to the can bottom forming part Y by drawing. Drawing is performed. Subsequently, as shown in FIG. 6A, the cup-shaped molded product X is fitted to the tip of the punch structure P, and the punch structure P is inserted into the tool pack 16 in the insertion direction. As shown in FIG. 6 (b), the cup-shaped molded product X fitted to the tip of the punch structure P is moved while sliding the outer peripheral surface of the redraw die 14, and the cup-shaped molded product X0 having a predetermined inner diameter. A redrawing process is performed to form the film. Next, as shown in FIGS. 6C to 6E, the punch structure P is inserted into the through hole of the tool pack 16, and the first ironing die 15, the second ironing die 15, and the third iron are sequentially formed. The can body forming portion Z of the cup-shaped molded products X1, X2 and X3 formed by ironing by the ning die 15 is stretched from the can bottom forming portion Y side toward the opening side of the can body forming portion Z, Ironing is performed to form a cup-shaped molded product X4 having a predetermined can height, can diameter, and body wall thickness.

  The ironing process will be described in more detail. First, as shown in FIG. 6 (c), the outer peripheral surface of the cup-shaped molded product X0 fitted to the punch sleeve is provided in the through hole of the tool pack 16. The first ironing process is performed by inserting the inner peripheral side of the first ironing die 15 thus formed. As a result, the cup-shaped molded product X1 moved in sliding contact with the first ironing die 15 is gradually stretched toward the tip of the can body forming portion Z with an increased amount of ironing, and the can body forming portion. Z is thinly formed. Next, the cup-shaped molded product X1 stretched by the first ironing die 15 is moved in sliding contact with the second ironing die 15 as shown in FIG. Done. Subsequently, the cup-shaped molded product X2 drawn by the second ironing die 15 is moved in sliding contact with the third ironing die 15 as shown in FIG. Is done. By the ironing process as described above, the can body forming portion Z of the cup-shaped molded product X2 is stretched and formed into a predetermined can height, can diameter, and body wall thickness. At this time, the second ironing process is started from the boundary between the can bottom forming part Y and the can body forming part Z of the cup-shaped molded product X1, so that 2 is stretched, and then the third ironing process is performed with a certain amount of ironing on the entire can body forming portion Z, so that the entire surface of the can body forming portion Z is caused by a change in the amount of ironing. Molded uniformly and smoothly without any difference in gloss. Then, the cup-shaped molded product X3 having the can body formed by the ironing process is struck to the doming die 17 of the doming station while being fitted to the punch structure P as shown in FIG. 6 (f). Then, the can bottom forming portion Y is formed into a dome shape.

The process of squeezing the metal surface between the outer diameter of the punch and the inner diameter of the die in the above forming process involves heat generation, so that the temperature of the punch must be adjusted, for example, by appropriate cooling. Patent Document 2 discloses a punch structure P for ironing a can having a cooling function. As shown in FIGS. 4 and 5, two pieces of resin cores m 1 and m 2 are inserted into the ram 8, and the temperature-controlled water is circulated to the front of the tip. The punch portion 1 has a structure in which the inside is hollowed out and the space is filled with temperature-controlled water. Temperature control water from the inflow pipe 21 is introduced from the front end side (dome side) 19 of the punch, and a flow path is formed from the rear side 20 to the discharge pipe 22. There is no flow path through which the temperature-controlled water sequentially flows and flows out, and is merely a continuous groove or clearance 18. In order to control the punch temperature, the ram 8 has a tube piping or a double structure that secures temperature-controlled water / air passages, but it has a complicated structure such as the core structure m1, m2 made of resin material. As a result, damage and deterioration due to changes over time will occur, and periodic replacement of parts will be necessary. In addition, durability is further reduced when high-speed operation is performed. Due to its complicated structure, it can be used for sealing, fixing parts, etc., and it is difficult to secure the temperature control water / air passage cross-sectional area, and the molding is troublesome and the productivity is poor.
JP, 6-142780, A "Molding method of a bottomed thin can body" Published on May 24, 1994 Paragraph [0014] thru | or [0021] and description of FIG. US Patent No. 6,598,450 "INTERNALLYCOOLED PUNCH" Registered July 29, 2003

  The problem to be solved by the present invention is to provide a simple structure that does not use a resin core in the ram portion in order to reduce the need for maintenance, and to supply temperature-controlled water and air supply so as to enable high-speed molding. Another object of the present invention is to provide a punch structure with improved cooling efficiency of the punch portion.

The punch structure of the present invention is provided with a ram composed of a single structure in which a thick air passage is formed at the center and a plurality of through holes parallel to the shaft are formed for temperature control water.
In addition, a large number of through holes of the punch structure of the present invention are arranged symmetrically with respect to the center axis of the ram.
Further, the punch structure of the present invention is provided with a through hole as a cavity in addition to the temperature control water and the air passage.
The punch sleeve of the punch structure according to the present invention is formed with a band-shaped temperature-regulating water flow path meandering under the surface.
In the punch sleeve of the punch structure of the present invention, an outer casing made of super hard material and an inner casing made of stainless steel are fitted with a cooling swivel.
The punch structure of the present invention is a single structure in which a punch sleeve is formed with a band-shaped temperature-regulating water flow path meandering under the surface and a plurality of through holes parallel to the axis for temperature-regulating water are formed. The ram part consisting of
The punch structure of the present invention forms a thick air passage in the center and a punch portion in which an outer casing made of super hard material and an inner casing made of stainless steel are cooled and fitted with a punch sleeve. A ram portion made of a single structure in which a large number of through-holes parallel to the axis are formed is integrated into a single structure by welding.

The punch structure of the present invention is provided with a ram having a thick air passage in the center and a large number of through-holes parallel to the shaft for temperature control water. The amount of water to be adjusted and the required supply amount of air can be secured sufficiently, and the structure of the ram is made of a single structure that does not use a resin core. Even if they are stacked, there is no risk of aging, and no maintenance is required.
In addition, since the numerous through holes of the punch structure of the present invention are arranged symmetrically with respect to the center axis of the ram, there is no occurrence of biased thermal deformation.
Furthermore, since the punch structure of the present invention is provided with a through-hole as a cavity in addition to the temperature control water and the air passage, the weight of the ram member can be reduced and a high-speed can can be made.
The punch sleeve of the punch structure according to the present invention is formed with a band-shaped temperature-regulating water flow path meandering under the surface, so that a punch with good heat exchange efficiency can be realized.

In the punch sleeve of the punch structure of the present invention, the outer casing made of super hard material and the inner casing made of stainless steel are fitted with a cooling swage, so that a strong integrated structure can be realized, and the rigidity and strength of the punch sleeve itself can be achieved. I was able to secure it.
The punch structure of the present invention is a single structure in which a punch sleeve is formed with a band-shaped temperature-regulating water flow path meandering under the surface and a plurality of through holes parallel to the axis for temperature-regulating water are formed. Since the ram portions made of these are connected, temperature-controlled water required for cooling can be supplied and efficient heat exchange can be realized.
The punch structure of the present invention forms a thick air passage in the center and a punch portion in which an outer casing made of super hard material and an inner casing made of stainless steel are cooled and fitted with a punch sleeve. The ram part consisting of a single structure with a large number of through-holes parallel to the shaft is integrated by welding, so the structure of the punch part and the structure of the ram part are both solid, and both members are welded. Because it is a solid bond, it can be used as a punch structure for maintenance-free high-speed cans.

  With reference to FIGS. 1 to 3, a punch cooling method and its structure in drawing and ironing of the present invention will be described. 1A is a cross-sectional view of the punch structure P according to the present invention having a cooling function, taken along an axial plane, and FIG. A sectional view cut along a plane orthogonal to the axial direction, and a diagram (c) is a sectional view cut along a plane perpendicular to the axial direction of the BB portion of (a). In the punch structure P of the present invention, the left side in the sectional view in the axial direction of (a) is the punch portions 1 and 2, the ram portion 8 is connected via the welded portion 7, and the right end side of the ram portion is connected to the slide yoke 13. It has a combined structure. In this punch structure P, the slide yoke 13 is reciprocated in the axial direction by a drive unit (not shown), and the outer peripheral surface of the can material that has been previously drawn and covered on the tip of the punch is shown in FIG. A plurality of stages of ironing are performed by inserting the inner peripheral sides of a plurality of ironing dies 15 provided in the through holes of the tool pack 16 as shown. By this ironing process, the can material placed on the tip of the punch is moved in sliding contact with the ironing die, so that it is stretched to a predetermined thickness, and the ironing amount gradually increases for each ironing die 15. The can body forming portion is thinly formed and elongated in the axial direction. The punch structure P of the present invention has temperature control water passages 9a and 9b in the ram portion 8 and a heat exchange channel 2a in the punch portion 2 in order to moderately cool the punch and can while suppressing the heat generated by the drawing process. Is provided. In addition, an air passage for removing the processed can from the punch portion is formed, the air passage 10 is formed in the ram portion 8, and the pipe 5 is connected to the portion connecting the ram portion 8 and the punch portions 1 and 2, Further, a bolt 3 provided with a through hole is connected to the punch portions 1 and 2 and is formed so as to penetrate through the axial center of the punch structure P as a whole. Further, the temperature-controlled water and air are supplied to the punch structure P that reciprocates in the axial direction for supplying the temperature-controlled water joint pipe 11 and the air joint pipe 12 disposed in the slide yoke 13, and a flexible (not shown). The temperature control water and the air supply source and the heat-exchanged temperature control water recovery tank are connected through a simple hose.

  Next, each partial structure will be described in detail. First, the structure of the ram portion 8 is formed by a single structure in which a plurality of through-holes are provided in the axial direction in a cylindrical stainless steel material without using a core as in Patent Document 2 above. ing. As can be seen from the cross-sectional view shown in FIG. 1 (c), an air passage 10 having a large diameter is formed in the central portion so that the maximum inner diameter can be secured even with respect to the assist air route, and the temperature control water is at an eccentric position. A forward path 9a and a return path 9b are formed. A plurality of temperature control water passages are provided for both the forward path 9a and the return path 9b, and a sufficient supply and discharge function of the temperature control water is provided in order to satisfy the cooling performance in the punch temperature control. In addition, in order to make the internal structure capable of canceling the thermal distortion of the ram portion due to temperature control water, the structure itself is made axially symmetric and the positions where the outgoing path 9a and the return path 9b of the temperature control water passage are arranged are also symmetric. It is. In consideration of high-speed can manufacturing, a hollow portion was formed to reduce the weight. Incidentally, in the example shown in FIG. 1, stainless steel of JIS standard SUS630 is used as a material, and four through holes having large diameters at intervals of 90 ° and temperature control water passages 9a and 9b arranged at intervals of 90 ° therebetween. A total of eight hollow portions are arranged in the vicinity. It should be noted that the number and diameter of these hollow portions are design matters determined by a balance between strength required for the ram portion and weight reduction under the condition of being axially symmetric.

  Next, regarding the structure of the punch portion, in order to cope with punch sleeve temperature control, a super hard material, for example, tungsten carbide, which is a sintered material, is used as an outer casing in the example shown in FIG. The stainless steel inner casing formed with the belt-shaped meandering groove 2a is combined, and the structure is cooled and bent to make the integrated structure firm. From the material of the punch sleeves 1 and 2, high thermal conductivity is obtained while ensuring the rigidity and strength of the punch sleeve itself. Between the outer punch sleeve 1 and the inner punch sleeve 2, a flow path is formed in which the release portion of the belt-like groove 2 a formed in the inner punch sleeve 2 is closed by the inner surface of the outer punch sleeve 1. For example, as shown in a development view in FIG. 2 (b), this flow path is formed in a straight line from the temperature-controlled water inlet provided at the base of the punch sleeve at the positions of 0 ° and 180 ° to the tip portion. The structure is formed so as to meander in the direction of the base, and communicates with the temperature-controlled water outlet provided at positions 90 ° and 270 ° of the base. In synergy with the temperature control channel configuration in the ram section that secures the amount of water supply, the configuration that flows in one direction without stagnation in the meandering channel instead of the straight channel as in the channel of Patent Document 2 is sufficient. A high heat exchange rate is achieved while ensuring a regulated flow rate.

As shown in FIG. 1 (a), the punch portion and the ram portion are joined by inserting a leading end side ram 6 having a small diameter portion having a stepped portion with the outer diameter dropped into the base portion of the punch. The large diameter portion of the ram 6 is integrated with the ram portion 8 and the welded portion 7. The leading end side ram 6 that is an interposed member communicates with a hole for inserting the pipe 5 serving as an air passage at the center, and the temperature adjustment water passages 9a and 9b of the ram portion 8 and the temperature adjustment water inlet / outlet. A temperature-controlled water flow path is formed.
The welded integrated structure prevents water leakage accidents, and has a solid structure, combined with the structure of the punch part, which is a chilled structure of super hard material and stainless steel, and the structure of the ram part, which is a single structure of stainless steel. Since the structure as a whole has a solid structure, it is possible to manufacture cans at high speed and to improve its durability.

It is an axial sectional view of one embodiment of the punch structure according to the present invention, and a transverse sectional view of the AA portion and the BB portion. It is a figure explaining the strip | belt-shaped groove | channel structure provided in the punch sleeve of one Example of the punch structure which concerns on this invention. It is the figure which showed the tool pack combined with the punch structure which concerns on this invention. It is a figure explaining the conventional punch structure provided with the cooling function, and is an axial sectional view of the whole structure. It is a figure explaining the temperature control flow path of the conventional punch structure provided with the cooling function, and its flow. It is a figure explaining the well-known process of shape | molding a can by drawing and ironing.

Explanation of symbols

1 Punch sleeve (outer) 2 Punch sleeve (inner)
3 bolt 4 lock nut 5 pipe 6 ram (tip side)
7 Ram welded portion 8 Ram portion 9a Temperature control passage (outward) 9b Temperature control passage (return)
DESCRIPTION OF SYMBOLS 10 Air passage 11 Temperature control water joint pipe 12 Air joint pipe 13 Slide yoke 14 Redraw die 15 Ironing die 16 Tool pack

Claims (7)

  A punch structure having a ram formed of a single structure in which a thick air passage is formed in the center and a plurality of through holes parallel to the axis are formed for temperature control water.   2. The punch structure according to claim 1, wherein the plurality of through holes are arranged symmetrically with respect to the central axis of the ram to prevent deformation due to thermal distortion of the ram.   The punch structure according to claim 1 or 2, wherein a through hole as a cavity is provided in addition to the temperature control water and the air passage to reduce the weight.   A punch structure in which a punch-shaped sleeve is formed with a band-shaped temperature-regulating water flow path meandering under the surface.   The punch structure according to claim 4, wherein an outer casing made of a super-hard material and an inner casing made of a stainless steel material are fitted with a cooling swivel.   The punch sleeve is connected with a punch portion in which a belt-like temperature control water flow path meandering under the surface is formed and a ram portion made of a single structure having a plurality of through holes parallel to the axis for temperature control water connection. Punch structure.   The punch structure according to any one of claims 1 to 3, wherein a punch portion and a ram portion in which an outer casing made of a super-hard material and an inner casing made of a stainless steel material are cooled and fitted together are integrally formed by welding. body.

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