JPS6323864B2 - - Google Patents

Description

[Detailed Description of the Invention] This invention is applicable to drum cans, pails, and tin plate 18
A method for directly forming a threaded cap part and a curved part such as a rounded part on a part of the top plate of a metal container such as a can or various small cans, and an apparatus for carrying out this method. It is.

A conventional metal container with a screw cap has one or two openings in a part of its top plate, and separate screw caps of different sizes but of the same structure are fitted into these openings and soldered. They were fixed by means such as electric or gas welding, or crimping by press working.

Among the conventional methods described above, soldering and welding methods are inefficient, so recently, most of the methods are fixing by caulking.

However, the method of fixing by caulking uses packing to prevent leakage, but depending on the material etc., it may cause caulking to the top plate due to temperature differences between the inside and outside of the can, external impact on the can, or pressure generated from the contents. Not only will the joints and packing of the cap become loose or deformed, causing the contents to leak, but also there is a risk of serious accidents occurring due to external fluid penetrating into the container.

An object of the present invention is to solve the above-mentioned drawbacks caused by the use of a screw cap.

Conventional methods for forming threads on an object include fixing the object to be machined or rotating a fixed workpiece, using a gear type or cam type such as a lathe or automatic thread cutting machine, or a tapping machine or a cam type. Some types use a thread rolling machine to form the threaded part. There is also a method of providing a large number of concavities and convexities parallel to the circumferential direction of a metal cylinder using an inner mold and an outer mold that can be expanded and contracted. However, there is no method or apparatus for directly forming a threaded portion on a partially opened protruding portion located off the center of the top plate of a metal container.

The principle of the processing method and device according to the present invention is that the rifling marks left on the bullet surface after firing a gun bullet, which are caused by the spiral shape formed inside the gun barrel, are different, and bullets fired from the same gun have different rifling marks. Because identical rifling marks are always left, identification of the firearm used was devised based on the principle that 100% identification can be made from the rifling marks of the bullet after firing.

That is, in this invention, a part of the top plate of the can is pressed to protrude into a cylindrical shape as the mouthpiece, and then the outside of the mouthpiece is sandwiched between the outer diameters of the halves, and the can descends while rotating in a spiral shape. The upper mold is screwed into the mouthpiece, and the inside of the mouthpiece is pushed outward by the extrusion action of the male screw on the outside of the upper mold, and the outside of this mouthpiece is pushed into the female thread inside the outer mold to form the product. The present invention provides a method for molding a threaded cap part by forming a rounded bent part with a lower die, and an apparatus for carrying out this method.

There are two types of this invention, an internal type and an external type, depending on the structure of the cylinder that operates the upper mold with a male thread on the outside by air or hydraulic pressure.The internal type operates only by the difference in the mechanism of the cylinder. The method of
The method and apparatus of the present invention using an external cylinder will be described below based on an embodiment shown in the accompanying drawings.

1 and 2 are a front view and a side view of an apparatus for carrying out the method of the present invention, in which 1 is the main body of the apparatus, and a supporting stand is shown from the upper end of the rear rising part 2 on the main body 1 toward the front. 3 is integrally provided, and a pair of left and right columns 4 are fixed between both sides of the front part of this stand 3 and both sides of the front part of the main body 1.

5 and 6 are top plate pedestals provided on the main body 1, the stand 5 is fixed to the main body 1, and the stand 6 advances and retreats toward the stand 5 along the guide frame 7 on the main body 1 as shown in Fig. 1. The guide frame 7 is equipped with an air or hydraulically actuated cylinder 8 for moving the platform 6 forward and backward.

The outer shape of the top plate holders 5 and 6 is circular or square depending on the top plate to be processed. In addition, semicircular recesses are provided in the opposing surfaces of both top plate holders 5 and 6, and outer molds 9 and 10 are fixed therein. cradle 5, 6
It has a half-shaped female thread that forms a circular hole with a female thread when the two are in close contact.

11 in FIGS. 1 and 2 is a vertical cylinder fixed directly above the outer molds 9 and 10 so that its mounting position in the vertical and front-back directions can be freely adjusted, and is operated by air or hydraulic pressure to raise and lower. This is what causes the shaft 12 to act. This elevating shaft 12 is movable up and down and rotatable, and has a threaded groove 13 formed on its outer side.

Reference numeral 14 denotes an upper mold fixed to the lower end of the lifting shaft 12, which has a female screw that fits with the female screw with a slight gap when the outer molds 9 and 10 are brought into close contact with each other. As shown in Fig. 1, an indicator line S is provided on the male screw part to indicate the start of thread cutting using a vertical groove, etc., and the female thread of the outer mold 9 is also shown to indicate the start of thread cutting that corresponds to the indicator line S. An indicator line is provided, and by aligning both indicator lines, the male thread and the female thread are screwed together correctly.

Reference numeral 15 in FIGS. 1 and 2 is a support frame attached so that it can move up and down with respect to the upright part 2 and the support column 4 and can be bolted to any position. It is mounted so that it can be moved and bolted to any position, and
4 and the indicator lines S of the outer molds 9 and 10 are used for adjustment to accurately screw them together.

A vertical screw hole into which the screw groove 13 of the lifting shaft 12 is screwed is provided in the center of the guide frame 16. The lifting shaft 12 is screwed into this screw hole, and the upper mold 14 is placed below the guide frame 16. It is located so that it is located.

Reference numeral 17 in FIGS. 1 and 2 is a cylinder fixed to the support base 3 behind the cylinder 11, and is operated by air or hydraulic pressure to raise and lower a piston rod 18 projecting downward.

A downward U-shaped top plate holding frame 19 is fixed to the lower end of this piston rod 18, and both ends of a plate spring 20 bent into a shallow V shape are attached to the lower part of this holding frame 19 using elongated holes and set screws. It is slidably mounted.

21 shown in FIG. 3 etc. is the top plate holder 5 on the main body 1.
A pneumatically or hydraulically actuated cylinder is fixed on the side end, and a piston rod moved back and forth by this cylinder 21 is oriented toward the pedestal 5 as a push rod 22.

Reference numeral 23 has its upper end directed toward a proper position outside the top plate holder 5, and its upper end slightly protrudes above the top plate holder 5 in a free state by a plurality of leaf springs whose rear ends are fixed onto the main body 1.

24 in Figures 1 and 2 is a guide rail in the front and back direction fixed to the inner bottom of the main body 1, and this rail 2
Attach the sliding base 25 to the base 25 and attach the fixing screws to fix the base 25 to any position on the rail 24.
be installed at the appropriate location.

A vertical cylinder 26 operated by air or hydraulic pressure is fixed on the sliding table 25, and a lower mold 28 is fixed on a piston rod 27 projecting above the cylinder 26.
The upper surface of this lower mold 28 is provided with an annular groove 29 for molding, and the top of the main body 1 is provided with an opening through which the lower mold 28 passes.

Reference numeral 30 in FIG. 3 denotes a plurality of limit switches attached to the pedestal 5 at appropriate intervals.
This switch 30, which only protrudes above the pedestal 5, is for actuating the cylinders 8 and 17.

In addition, in the case of the embodiment, the outer molds 9 and 10 and the upper mold 14
and a smaller outer mold 9' behind the lower mold 28,
10', upper mold 14', and lower mold 28' are arranged,
Since these are attached by exactly the same mechanism as the front molds 9, 10, 14, and 28 and operate simultaneously as necessary, a detailed explanation of their construction will be omitted.

8 and 9 show examples of the base portion 34 of the top plate 32 formed by press working in the first step,
An L-shaped peripheral edge 33 is provided around it, and a base portion 34
is cylindrical and faces upward or downward.

In addition, when the container is circular, the top plate 32 may have a disc shape,
In the case of a rectangular shape, it is needless to say that it is a rectangular shape, and the size varies depending on the capacity of the container, and the pedestals 5 and 6 can also be replaced with ones having different shapes and sizes.

The apparatus for implementing the molding method of the present invention using an external cylinder has the above-mentioned configuration, and a method for molding a threaded cap part on a top plate using this apparatus will be described below.

First, the cylinder 11, guide frame 16, and sliding base 2
Adjust the mounting position of 5 so that the center when the outer molds 9 and 10 are closed and the center of the upper mold 14 and the lower mold 28 are aligned on the same vertical line, operate the cylinder 11 with the manual switch, and lower the lifting shaft 12. After aligning the indication line S of the male screw of the upper mold 14 with the indication lines of the outer molds 9 and 10, the upper mold 14 is raised.

Next, the top plate 32 made of a thin steel plate formed as shown in FIG. Fit between outer molds 9 and 10.

When the top plate 32 is placed on the pedestals 5 and 6 in this way, the operating piece 31 of the limit switch 30 is pushed by the top plate 32, so that the solenoid valve acts and the cylinder 17 shown in FIGS. 1 and 2 and the cylinder 17 shown in FIGS. , the cylinders 8 in FIG. 4 work almost simultaneously, the piston rod 18 descends,
The pedestal 6 moves toward the pedestal 5, and at the same time as the outer molds 9 and 10 are pinched by the mouthpiece 34, the leaf spring 20 at the lower end of the presser frame 19 presses the top plate 32 onto the pedestal 5 and extends horizontally. The top plate 32 is fixed, and at the same time, the top end of the leaf spring 23 is pushed down by the top plate 32.

As mentioned above, when the outer molds 9 and 10 clamp the mouthpiece 34, the limit switch attached to the pedestal 5 is activated, and the relay and solenoid valve are activated in sequence, causing the cylinder 1
1 to lower the elevating shaft 12. At this time, the threaded groove 13 on the outside of the elevating shaft 12 rotates along the threaded hole of the guide frame 16 and descends.

The upper mold 14 has thus descended together with the lifting shaft 12.
When a limit switch or the like detects that the cylinder approaches the top plate 32, the control device of the cylinder 11 operates to reduce the descending speed of the lifting shaft 12 to the speed necessary for forming the thread of the base part 34, and the male thread of the upper mold 14 is screwed into the base portion 34 in the outer molds 9, 10.

The upper mold 14 screwed into the mouthpiece 34 spirally pushes out the inside of the mouthpiece 34 and pushes into the female threads of the outer molds 9 and 10, rotates in a spiral and descends, as shown in FIG. When the upper mold 14 reaches the lowest limit, the limit switch that detects the lower limit of the upper mold 14 is activated, and the lowering of the lifting shaft 12 is stopped. At the same time, the solenoid valve of the control device for the cylinder 26 is activated to operate the cylinder 26. The piston rod 27 is the lower mold 28
Then, as shown in FIG. 6, the unthreaded portion at the lower end of the base portion 34 is bent outward by the annular groove 29 of the lower die 28 to form a rounded portion b.

When the lower mold 28 that has risen in this way forms the rounded part b and reaches the upper limit, the limit switch is activated, the solenoid valve is switched, the cylinder 26 is activated, the piston rod 27 and the upper mold 28 are lowered, and the cylinder 11 is also lowered. Working simultaneously, the lifting shaft 12 and the upper mold 14 move upward while rotating in the opposite direction to when they are lowered, and are removed from the mouthpiece 34. When the lifting shaft 12 reaches its upper limit, it stops.

When the lifting shaft 12 reaches its upper limit in this way, the limit switch is activated and the cylinder 8 is operated, its piston rod moves back together with the top plate holder 6, and the outer mold 9,
10 opens, and at the same time the cylinder 17 also works to raise the piston rod 18, and the top plate 32 is moved by the leaf spring 20.
At the same time, the cylinder 21 works to advance the push rod 22 and push the periphery 33 of the top plate 32 as shown in FIG. The top plate 32 is pushed up by the leaf spring 23. The cylinder 21 is the push rod 2
It retreats to its original position due to the action of the limit switch that operates when 2 is advanced.

Through the above-mentioned action, a threaded cap with a radiused portion b as shown in FIGS. 10 and 11 was formed, but when molding a cap without a radiused portion as shown in FIG. 28 may be omitted.

In addition, in the case of the internal cylinder shown in Fig. 13,
Lifting shaft 12 having thread groove 13 in cylinder 11
The upper and lower ends are rotatably connected to the upper and lower pistons 35, 36 in the cylinder 11, and the elevating shaft 12 is rotatably fitted into a cylindrical body 37 fixed in the cylinder 11. The spiral protrusion 38 on the inner surface is screwed into the screw groove 13, and the extension shaft 39 fixed to the lower end of the lifting shaft 12 is made to protrude outside the cylinder, and the upper mold 14 is fixed to the lower end. Therefore, in this case, there is no need for a screw hole in the guide frame 16, and a simple guide hole into which the extension shaft 39 is loosely fitted is sufficient.
may be omitted.

This invention provides a base portion 3 provided on a top plate 32 using semicircular outer molds 9 and 10 that are divided into two parts as described above.
The upper die 14 is screwed into the mouthpiece 34 while holding the upper mold 4, and the outer peripheral surface of the mouthpiece 34 is pushed into the female threads of the outer molds 9 and 10, so it is made of thin steel plate or the like. The molding of the cap part 34 can be performed easily and accurately. After molding, the upper mold 14 immediately rotates in reverse and rises, the outer molds 9 and 10 open, and the lower mold 28
The top plate can be easily removed after molding because it descends, and by forming the threaded cap part directly on the top plate through a series of continuous operations, there is no leakage caused by caulking or the type of packing used in the past. It is completely preventable.

[Brief explanation of the drawing]

FIG. 1 is a front view showing one embodiment of the device of the present invention, FIG. 2 is a side view of the same, FIG. 3 is a partially cross-sectional plan view, FIG. 5. FIG. 6 and FIG. 7 are vertical sectional front views of the main parts of each step in the molding state, FIGS. 8 and 9 are vertical sectional views showing each example of the mouthpiece before molding, and FIGS. 10 to 12 The figures are longitudinal sectional views showing examples of the mouthpiece portion after molding, and FIG. 13 is a longitudinal sectional view showing an internal cylinder. 5, 6...Top plate holder, 9,10...Outer mold, 14
... Upper mold, 32 ... Top plate, 34 ... Mouth part.

Claims (1)

[Scope of Claims] 1. An opening is provided at a position offset from the center point of the top plate of a metal container, and the peripheral edge of the opening is made to protrude in a cylindrical shape as a mouthpiece.Then, the mouthpiece is turned downward and the outside is turned inside. A pair of half-shaped outer molds each having a female thread are placed between them, and the upper mold, which has a male thread formed on the outside, is screwed into the mouthpiece while rotating spirally from above, thereby creating a screw-like shape inside the mouthpiece. By pushing the outside of the mouthpiece outward into the female thread of the outer mold, a male thread is formed on the outside of the mouthpiece and a female thread is formed on the inside at the same time. After forming the curved part, lower the lower mold,
A threaded cap part for a metal container, characterized in that the threaded cap part is formed directly on the opening protrusion of the metal container by rotating the upper mold in the opposite direction and removing it from the cap part, and by opening the outer mold and removing it from the cap part. Molding method. 2 A pair of left and right top plate pedestals that receive a metal top plate with a cylindrical base formed at a position offset from the center point, and a pair of left and right female screw-shaped outer molds that sandwich the downward facing base from both sides. At the same time, means for opening and closing both of the outer molds are provided, and above the top plate cradle, an appropriate elevating means and rotating means are used to descend while rotating in a spiral shape, and to be screwed into the mouth part held between the outer molds. A threaded metal container characterized in that an upper mold having a male thread is provided, and a lower mold is provided below the cradle and rises to form a rounded bent part at the tip of a cap part without a threaded part. Mouth part forming device.