JP2014200845A - Method for manufacturing cartridge for gun - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a cartridge for a gun in a single transfer press for deep drawing including plural stations.SOLUTION: A method for manufacturing a cartridge for a gun comprises: a process (a) for supplying a metal sheet; a process (b) for cutting a metal bracket of the metal sheet; a process (c) for transferring the metal bracket obtained in the process (b) to a primary formation station equipped with a punch and a die and forming a metal disk sheet into a metal cup; a process (d1) for transferring the metal cup obtained in the process (c) to a secondary formation station equipped with many punches and dies and deep-drawing the metal cup into te cartridge; and a process (e1) for removing the cartridge from a transfer press for deep drawing including plural stations. There is no intermediate cleaning process, acid cleaning process and/or painting process between the process (a) and the process (e1).

Description

  The present invention relates to a novel method for producing gun cartridges.

  Typically, gun cartridges are drawn from sheet metal disks in three “stages”. First, a cup is formed from a sheet-like metal disk. The cup is then drawn to the desired length by a number of forming operations until a part of the desired length is obtained with a punch that reduces the diameter. Then, if necessary, a neck is formed in the drawn part. Finally, a groove is provided in the part that has been drawn to form a neck, and a final cartridge is formed.

  After each drawing step, the parts are annealed, pickled, washed with water and exposed to further quality improvement measures.

  The parts should be clean during the annealing process and require cleaning before annealing. After annealing, the parts are pickled, bonded and / or lubricated as necessary for subsequent drawing operations.

  Depending on the caliber, the drawing process is typically done in a transfer press, and in many sets (stations) containing multiple pairs of punches and dies, the product is deep drawn and deep drawn. Receive the workpiece away from the drawing tool. When this drawing is performed in a transfer press, the transfer is performed using a mechanical gripper.

  Usually the transfer press comprises 5 to 12 stations. Typically, the material cures with a significant decrease in sheet strength from an initial strength of about 3 mm to 4 mm to a final strength of about 0.3 mm. In addition, the forming ability decreases with each step. For this reason, state-of-the-art processes require at least one other intermediate annealing process (including cleaning and pickling), which may be even more dependent on the caliber.

  After ironing in the transfer press, a neck formation process is performed on the shell of most rifle guns. The neck formation is performed after the annealing process for reducing the material stress before the critical forming process. Typically, neck formation takes place at two stations.

  Groove formation and trimming is performed using special equipment that is separate from the transfer press. To achieve these, the cartridge case is fixed to the collet chuck and rotated while the forming turning tool cuts the groove and the second tool finishes the entire length.

  It can be easily understood that such a process requires labor, is expensive, and requires a large investment.

  Accordingly, it is an object of the present application to provide a method for producing a gun cartridge that can be implemented with a single transfer press.

A method for producing a gun cartridge according to the present invention includes:
A method of manufacturing a gun cartridge in a single transfer press for deep drawing including multiple stations,
A step (a) of supplying the metal sheet to a transfer press for deep drawing including a plurality of stations, including a blank forming device for cutting a blank from the metal sheet;
Cutting the metal blanket of the metal sheet (b);
A step (c) of transferring the metal blanket obtained in step (b) to a primary forming station comprising a punch and a die and forming the metal disk sheet in a metal cup;
A step (d1) of transferring the metal cup obtained in step (c) to a secondary forming station having a number of punches and dies, and deeply drawing the metal cup into a cartridge;
A step (e1) of removing the case from a deep drawing transfer press including a plurality of stations;
And there is no intermediate washing step, pickling step, and / or bonding step between step (a) and step (e1).

  In an embodiment of the present invention, step (b) for forming a blank from a metal sheet and step (c) for forming a cup are performed at one cutting and forming station.

If a groove is formed in the case,
A method of manufacturing a gun cartridge having a groove in a single transfer press for deep drawing including a plurality of stations, comprising:
Supplying a metal cup to a primary forming station in a deep drawing transfer press comprising a plurality of stations comprising a number of punches and dies (d2);
Transferring the metal cup obtained in step (d2) to another forming station comprising a punch and a die (e2) to reduce the diameter of the bottom of the cartridge case to a desired groove diameter;
Transferring the shell with reduced diameter of the bottom obtained in step (e2) to another forming station comprising a punch and die for forming a groove, wherein the die can be divided after operation; A step (f1) that is a split die that can be formed;
A step (g1) of dividing the split die and removing a case with a groove formed from a transfer press for deep drawing including a plurality of stations;
It is advantageous to obtain a medicinal shell in a manner that comprises no intermediate washing, pickling and / or baking steps between step (d2) and step (g1).

Also,
A step (a) of supplying the metal sheet to a transfer press for deep drawing including a plurality of stations, including a blank forming device for cutting a blank from the metal sheet;
Cutting the metal blanket of the metal sheet (b);
A step (c) of transferring the metal blanket obtained in step (b) to a primary forming station comprising a punch and a die and forming the metal disk sheet in a metal cup;
The cup is transferred to step (d2), and there is no intermediate washing step, pickling step, and / or baking step between step (a) and step (g1),
It is preferable that the step of cutting a blank from the metal sheet and the step of forming a cup of the metal sheet are sequentially performed in the same transfer press for deep drawing including a plurality of stations.

Among the cartridge cases, especially those used for rifles, the presence of a neck is necessary. A step (d3) of supplying a metal cup to the primary forming station in a deep drawing transfer press including a plurality of stations including a plurality of punches and dies, and deep drawing the metal cup into a cartridge;
A step (e3) of transferring the shell obtained in step (d3) to another forming station for forming a neck on the shell;
Removing the cartridge case from the transfer press for deep drawing including a plurality of stations (f2);
And there is no intermediate washing step, pickling step, and / or baking step between step (d3) and step (f2),
In a method of manufacturing a gun cartridge having a neck in a single transfer press for deep drawing including multiple stations, the neck may be formed in the same transfer press for deep drawing including multiple stations. It is advantageous.

Also,
A step (a) of supplying the metal sheet to a transfer press for deep drawing including a plurality of stations, including a blank forming device for cutting a blank from the metal sheet;
Cutting the metal blanket of the metal sheet (b);
A step (c) of transferring the metal blanket obtained in step (b) to a primary forming station comprising a punch and a die and forming the metal disk sheet in a metal cup;
The cup is transferred to step (d3), and there is no intermediate washing step, pickling step, and / or baking step between step (a) and step (f2),
It is preferable that the step of cutting a blank from the metal sheet and the step of forming a cup of the metal sheet are sequentially performed in the same transfer press for deep drawing including a plurality of stations.

When manufacturing a case with a groove or neck,
A step (d4) of supplying the metal cup to a primary forming station in a deep drawing transfer press including a plurality of stations including a plurality of punches and dies, and deep drawing the metal cup into a cartridge;
Transferring the shell obtained in step (d4) to another forming station comprising a punch and die, and reducing the bottom of the shell to a desired groove diameter (e4);
Transferring the shell with reduced diameter of the bottom obtained in step (e2) to another forming station comprising a punch and die for forming a groove, wherein the die can be divided after operation; A step (f3) that is a split die that can be formed;
Disassembling the split die, transferring the cartridge formed with the groove obtained in step (f3) to another forming station, and forming a neck in an elongated metal cup (g2);
Removing the case from the transfer press for deep drawing including a plurality of stations (h1);
And there is no intermediate washing step, pickling step, and / or baking step between step (d4) and step (h1),
A cartridge case can be manufactured by a method of manufacturing a gun case cartridge having a neck in a single transfer press for deep drawing including a plurality of stations.

Also,
A step (a) of supplying the metal sheet to a transfer press for deep drawing including a plurality of stations, including a blank forming device for cutting a blank from the metal sheet;
Cutting the metal blanket of the metal sheet (b);
A step (c) of transferring the metal blanket obtained in step (b) to a primary forming station comprising a punch and a die and forming the metal disk sheet in a metal cup;
The cup is transferred to step (d3), and there is no intermediate washing step, pickling step, and / or baking step between step (a) and step (h1),
It is preferable that the step of cutting a blank from the metal sheet and the step of forming a cup of the metal sheet are sequentially performed in the same transfer press for deep drawing including a plurality of stations.

  For example, when forming a neck in many rifle gun cartridges, it is desirable to form the neck in a transfer press for deep drawing including a plurality of stations, which is the same as all preceding steps. In the above machine, the neck is preferably formed in the final step. The neck of a handgun cartridge is usually not formed.

  A transfer press forming station for deep drawing including a plurality of stations usually includes a pair of punches and dies that are formed into a metal cup by first forming a metal sheet, and then a slender bowl of the metal cup, and a stripper. And an ejector and a gripper for transferring the cup of the cartridge case from one forming station to the next. If a neck is formed, the forming station does not have a punch. There are only a die that forms a neck on the open side of the shell and an inner pilot to maintain the wall thickness.

  The present invention also provides a transfer press for deep drawing including a plurality of stations for producing gun cartridges in a single machine. The transfer press includes a cutting device for cutting a disk from a metal sheet, and a number of forming stations for drawing and forming the metal disk, wherein at least one forming station includes a punch and a die, The die is a split die for forming a groove.

FIG. 1 is a cross-sectional view showing the assembled state of punches and dies in an embodiment of the present invention. FIG. 2 is a cross-sectional view showing a state where the punch and the die are divided in the embodiment of the present invention.

  According to the invention, a metal sheet, preferably a brass sheet, is fed directly into a transfer press for deep drawing. Preferably, a zigzag feeder is used to supply a plurality of cuts, and the material is supplied to a cutting tool that cuts a disk from a metal sheet. Zig-zag feeders make the most efficient use of material without unnecessarily wasting material.

  Thereafter, a cup is formed in the transfer press and the cup is moved to a subsequent station in the transfer press, preferably without any intermediate cleaning, pickling, and / or baking. During the various stages of formation, the shell thickness is reduced to the final thickness.

In order to allow further deep drawing and ironing operations to achieve the final wall thickness without any tempering treatment, it is necessary to reduce the true strain with each operation. . Preferably, according to the process of the present invention, the number of forming stations (a pair of punches and dies) is greater than the number in known processes. Preferably, the deep drawing transfer press comprising a plurality of stations used in the method according to the invention comprises a total of 12 to 25 forming stations, more preferably 15 to 25 forming stations. For example, in order to include a neck without performing any intermediate tempering step, the number of forming stations used in step (e ₃ ) is preferably 3 to 7, preferably 4 to 5 Is most preferred.

  In step (c), the cup is preferably formed in one forming station, where it is preferred that the metal thickness is reduced by 40% to 70% while the cup is formed. is there.

  Preferably, the number of forming stations for carrying out the cup drawing and forming step (d) to form the shell is from 3 to 9, more preferably from 4 to 8, for example from 5 to 7 It is. In these forming stations, the thickness of the cup or medium squeezed shell is reduced at a higher rate during the drawing stage, which is earlier than stage (d), than after stage (d). It is preferable to do. For example, according to a preferred embodiment, the cup thickness is reduced by 30% to 50%, more preferably about 40% at the primary forming station of step (d). On the other hand, this reduction is typically about 60% to 70%.

  According to a further preferred embodiment, the thickness of the drawn shell is reduced at a lower rate at the secondary forming station of step (d) than at the primary forming station of step (d). The wall thickness of the drawn shell is preferably reduced from 20% to 30% at the secondary forming station of step (d).

  According to an even more preferred embodiment, the thickness of the drawn shell is reduced at a lower rate at the stage (d) tertiary forming station than at the stage (d) secondary forming station. The wall thickness of the drawn shell is preferably reduced from 10% to 25%, more preferably from 10% to 20% in the tertiary forming station of step (d). On the other hand, this reduction is typically about 25% to 35%.

  According to an even more preferred embodiment, the thickness of the drawn shell is the proportion at the tertiary forming station of step (d) at the quaternary forming station of step (d) and any subsequent forming station. Decreases at a rate equal to or lower than The wall thickness of the drawn shell is preferably reduced by 10% to 20% at the quaternary forming station in step (d) and any subsequent forming station.

  As the number of forming stations increases, and as the bed size increases, the stress during forming and the stress during coining may increase, resulting in wrinkling of the punch. The pressing force, which depends on the diameter of the gun cartridge, is preferably selected between 75 to 250 tons, and the bed length is preferably 1000 to 3000 mm. Preferably, a ridged mechanical press or ideally a servo spindle press is used, which can positively correct punch wrinkles.

  Preferably, one or two flash holes are opened in the drawn cartridge case in a deep drawing transfer press.

  As mentioned above, state-of-the-art groove forming processes are typically performed in a turning process by an external operation to remove material from the blank. However, the method according to the invention first integrates the grooving step with a transfer press and no material is removed while the grooving is being formed.

  The groove is formed in two stages. For groove formation, the first operation is a drawing operation that reduces the diameter of the bottom of the cartridge case to the desired groove diameter. In another station in the transfer press for deep drawing, the bottom of the case is held by a split punch, and the bottom and a ribbed primer are formed on the case. The material moves radially, thereby forming a groove. In order to remove the cartridge case from the split punch, the punch is divided into a plurality of segments.

  The above description is further demonstrated by attaching FIG. 1 (concentrated state) and FIG. 2 (divided state), which are cross-sectional views showing a split punch according to the present invention.

Claims (14)

A method of manufacturing a gun cartridge in a single transfer press for deep drawing including multiple stations,
(A) supplying the metal sheet to a transfer press for deep drawing including a plurality of stations, including a blank forming device for cutting a blank from the metal sheet;
Cutting the metal blanket of the metal sheet (b);
Transferring the metal blanket obtained in step (b) to a primary forming station comprising a punch and die, and forming the metal disk sheet in a metal cup (c);
Transferring the metal cup obtained in step (c) to a secondary forming station having a number of punches and dies, and deeply drawing the metal cup into a cartridge case (d1);
Removing the shell from a deep drawing transfer press including a plurality of stations (e1);
A method for producing a gun cartridge, wherein there is no intermediate cleaning step, pickling step and / or baking step between step (a) and step (e1). A method of manufacturing a gun cartridge having a groove in a single transfer press for deep drawing including a plurality of stations, comprising:
Supplying a metal cup to a primary forming station in a deep drawing transfer press comprising a plurality of stations comprising a number of punches and dies (d2);
Transferring the metal cup obtained in step (d2) to another forming station comprising a punch and die and reducing the diameter of the bottom of the cartridge case to a desired groove diameter (e2);
Transferring the cartridge case with reduced bottom diameter obtained in step (e2) to another forming station comprising punches and dies for forming grooves, wherein the dies can be divided after operation; A step (f1) that is a split die that can be formed;
A step (g1) of dividing the split die and removing the cartridge case with grooves formed from a transfer press for deep drawing including a plurality of stations;
A method for producing a gun cartridge, wherein there is no intermediate washing step, pickling step and / or baking step between step (d2) and step (g1). (A) supplying the metal sheet to a transfer press for deep drawing including a plurality of stations, including a blank forming device for cutting a blank from the metal sheet;
Cutting the metal blanket of the metal sheet (b);
Transferring the metal blanket obtained in step (b) to a primary forming station comprising a punch and die, and forming the metal disk sheet in a metal cup (c);
The cup is transferred to step (d2), and there is no intermediate washing step, pickling step, and / or baking step between step (a) and step (g1). To manufacture a gun cartridge case. A method of manufacturing a gun cartridge having a neck in a single transfer press for deep drawing including a plurality of stations, comprising:
Supplying a metal cup to a primary forming station within a transfer press for deep drawing including a plurality of stations including a plurality of punches and dies, and deep drawing the metal cup into a cartridge (d3);
Transferring the shell obtained in step (d3) to another forming station and forming a neck on the shell (e3);
Removing the cartridge case from the transfer press for deep drawing including a plurality of stations (f2);
And a method for producing a gun cartridge, wherein there is no intermediate washing step, pickling step and / or baking step between step (d3) and step (f2). (A) supplying the metal sheet to a transfer press for deep drawing including a plurality of stations, including a blank forming device for cutting a blank from the metal sheet;
Cutting the metal blanket of the metal sheet (b);
Transferring the metal blanket obtained in step (b) to a primary forming station comprising a punch and die, and forming the metal disk sheet in a metal cup (c);
The cup is transferred to step (d3), and there is no intermediate washing step, pickling step, and / or baking step between step (a) and step (f2). To manufacture a gun cartridge case. A method of manufacturing a gun cartridge having a neck in a single transfer press for deep drawing including a plurality of stations, comprising:
Supplying the metal cup to a primary forming station in a transfer press for deep drawing including a plurality of stations including a plurality of punches and dies, and deep drawing the metal cup into a cartridge (d4);
Transferring the shell obtained in step (d4) to another forming station comprising a punch and die and reducing the bottom of the shell to a desired groove diameter (e4);
Transferring the cartridge case with reduced bottom diameter obtained in step (e2) to another forming station comprising punches and dies for forming grooves, wherein the dies can be divided after operation; A step (f3) that is a split die that can be formed;
(G2) dividing the split die and transferring the case formed with the groove obtained in step (f3) to another forming station to form a neck in an elongated metal cup;
Removing the shell from a transfer press for deep drawing including a plurality of stations (h1);
And a method for producing a gun cartridge, wherein there is no intermediate washing step, pickling step and / or baking step between step (d4) and step (h1). (A) supplying the metal sheet to a transfer press for deep drawing including a plurality of stations, including a blank forming device for cutting a blank from the metal sheet;
Cutting the metal blanket of the metal sheet (b);
Transferring the metal blanket obtained in step (b) to a primary forming station comprising a punch and die, and forming the metal disk sheet in a metal cup (c);
The cup is transferred to step (d4), and there is no intermediate washing step, pickling step, and / or baking step between step (a) and step (h1). To manufacture a gun cartridge case.   The method for producing a gun cartridge according to any one of claims 1 to 7, wherein the metal sheet is made of brass.   9. Transfer press for deep drawing including the plurality of stations comprises a total of 12 to 25 pairs, preferably 15 to 25 pairs of punches and dies. How to make gun cartridges.   10. The method of manufacturing a gun cartridge according to any one of claims 1 to 9, wherein the tertiary forming station comprises 3 to 5 pairs of punches and dies for performing step (e).   The method for producing a gun cartridge according to any one of claims 1 to 10, wherein the transfer press for deep drawing including the plurality of stations generates a pressing force of 75 to 250 tons.   The method for producing a gun cartridge according to any one of claims 1 to 11, wherein the deep drawing transfer press including the plurality of stations has a platform size of 1000 mm to 3000 mm.   The method for manufacturing a gun cartridge according to any one of claims 1 to 12, wherein the transfer press for deep drawing including the plurality of stations includes a servo spindle press for positively correcting punch wrinkles. . Deep drawing comprising a plurality of stations for producing gun cartridges in a single machine comprising a cutting device for cutting a disk from said metal sheet and multiple pairs of punches and dies for squeezing the metal disk Transfer press for
A transfer press characterized in that, for at least one pair of punch and die, the die is a split die for forming a groove.

Images