JPS649095B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a surface hardening process in which the outer peripheral flange edge of the opening of an empty can or a can body filled with contents is double-sealed together with the outer peripheral curled edge of the can lid that is superimposed and polymerized, and a smooth surface. This relates to a finished can lid tightening tool.

In the case of can bodies filled with this kind of contents, can lid seaming work is performed in high pressure steam, so the can lid seaming tool is a tool used in an atmosphere containing a large amount of moisture. In addition, since the workpiece is a can, which is a metal container containing food, etc., rust on the tool itself may cause rust to get into the can, and the can may be damaged due to rust. This must be avoided at all costs, as it causes severe wear and shortens tool life.

Corrosion resistance with low chromium (Cr) content increases mechanical hardness and makes it difficult to rust due to oxidation.
For example, high-speed steel cannot be used because it has low oxidation resistance, otherwise rust will form on the parts that come into pressure contact with the cans and can lids.
As a result, it is clear that unnecessary flaws are caused in the cans, rust is mixed into the cans, and leakage cans occur frequently due to poor sealing accuracy.

In addition, even in the case of empty cans, if the can bottom lid or can body gets scratches when the can bottom lid is tightened, it may cause damage during subsequent storage, cleaning before filling, filling, or tightening the can top lid. Sometimes rust occurs and the same thing happens.

As shown in FIGS. 1 to 4, the prescribed series of operations performed by the can lid tightening tool are as follows: A can body 2 on which a can lid 1 is placed is carried onto a lifter plate 3 that revolves and rotates on its own axis. The can lid 1 is fitted onto the upper seaming chuck 4 which synchronously revolves and rotates together with the lifter plate 3 as the can lid rises, and the upper and lower parts are gripped by the seaming chuck 4 and the lifter plate 3, and at the same time the primary Minglor 5
comes horizontally, and the ring groove 5a of the primary seaming roll 5 is attached to the outer curled edge 1a of the can lid 1 backed up by the lip 4a of the seaming chuck 4.
The can lid 1 is rapidly rotated while applying pressure on the inner surface, and the outer curled edge 1a is rolled under the open outer flange edge 2a of the can body 2 (see Fig. 3), and then the secondary seaming roll 6 is rotated. Come horizontally 1
Next, the outer flange edge 2a and the outer curled edge 1a of the can body 2 and can lid 1 rolled up by the seaming roll 5
is compressed and filled between the annular groove portion 6a of the secondary seaming roll 6 and the outer circumferential surface _4a1 of the lip portion 4a of the seaming chuck 4 to form the seamed portion α (see FIG. 4). At the same time as the secondary seaming roll 6 retreats, the lifter plate 3 descends, and the can container is automatically carried out of the lifter plate 3.

Due to such harsh processing conditions, increased processing speed, and the use of high-hardness lid materials made of stain-free steel, which have recently been frequently used, the life of conventional martensitic stainless steel can lid tightening tools has decreased. As a result, frequent replacement of seaming tools and tool management for maintenance, inspection, and maintenance have become extremely difficult.In order to eliminate lower operating rates and variations in the quality of cans and containers, tungsten carbide has been added to the required parts of seaming chucks and seaming rolls. Attempts were made to harden the surface of the coating, but tungsten carbide WC was prone to oxidative decomposition at high temperatures, and as a result, it could not withstand high-speed cutting, making it impossible to put it to practical use. Next came the invention of Utility Model No. 55-7320, in which the seaming chuck and seaming roll were coated with titanium carbide, and the invention of Utility Model Publication No. 7320, in which a titanium carbide coating was applied after smoothing the designated areas of the can lid seaming tool. 57−
No. 14246, and although this idea and invention achieved almost the intended purpose and paved the way for practical application, it was still insufficient and there was still room for further improvement.

That is, the titanium carbide coating adopted as a surface hardening means in the above idea and invention is generally characterized by high hardness and a small coefficient of friction, and in particular, in the above invention, it is coated after smoothing the predetermined parts of the tool. Therefore, although the surface of the titanium carbide coating layer was sufficiently smooth, there was a problem in that it caused abrasion scratches on the can body during processing.

Although the coefficient of friction is small, the surface of the titanium carbide coating layer has minute irregularities when viewed microscopically under microscope magnification, and these irregularities have extremely high hardness, so they are pressed against the can body during the seaming process. This is because the can body was not easily flattened even when the can body was flattened. In other words, the micro-Vickers hardness of the titanium carbide coating layer is 3800, while the Vickers hardness of the low-carbon steel plates for tin and chrome-plated can lids and can bodies (especially when using ultra-thin plates or when applying small pressure loads in hardness tests). It is measured by micro-Bitzker's hardness, but its value is the same as Bitker's hardness) is 80 ~
220, and the hardness differs by one to two orders of magnitude, so the minute irregularities on the surface of the titanium carbide coating layer on the seaming roll, seaming chuck, and lifter plate can cause damage to the can lid and can body. It worked as a so-called file, creating scratches.

In this case, the can lid tightening tool has more stable durability, wear resistance, corrosion resistance, heat resistance, and oxidation resistance, and does not cause the aftereffects of rust due to scratches on the workpiece material during machining. Its appearance is eagerly awaited.

In response to the long-awaited demand, the present invention has the durability of super hardness,
To solve the above-mentioned problems, we provide a can lid tightening tool that has been subjected to a surface hardening treatment that has wear resistance, heat resistance, oxidation resistance, and corrosion resistance, and that has been processed to have a smooth surface finish after the surface hardening treatment. This is what I am trying to do.

An embodiment of the invention will be described with reference to FIG.

The can lid seaming tool A of the present invention includes a seaming chuck 4 made of martensitic stainless steel that fits inside a can lid 1, and a can that is superimposed so as to be close to the outer periphery of the seaming chuck 4 so as to be freely accessible. A martensitic stainless steel primary seaming roll 5 and a secondary seaming roll 6, which can be rotated freely, tighten the outer peripheral curled edge 1a of the lid 1 and the outer peripheral flange edge 2a of the can body 2, and the can lid 1 is mounted on the opening. The lifter plate 3 is made of a martensitic stainless steel lifter plate and can be moved up and down, on which the can body 2 is placed, and the lifter plate 3 is made of martensitic stainless steel and can be moved up and down to press and fit the can lid 1 into the seaming chuck 4. When hardening the surface of the required parts of the tightening tool A, the outer circumferential surface 4 of the seaming chuck 4, which is in back-up contact with the inner circumferential surface 1b of the can lid 1, is the most likely to wear.
After grinding, the lip portion 4a including a ₁ is subjected to honing, shot peening, etc. in order to prevent the slipping phenomenon with the inner circumferential surface 1b of the can lid 1, which comes into contact with the can lid 1 during the seaming operation, and to exhibit sufficient braking function. The surface is roughened to about 5 to 15 microns by rough surface preliminary processing to form a rough surface, while the upper surface of the guide flange portion 4c that engages with the engagement grooves 5b and 6b of the seaming rolls 5 and 6 is ground. After lap polishing,
A smooth surface is formed by pre-processing the smooth surface such as buffing, and then gaseous tetrachloride is applied over the entire seaming chuck 4, which is limited to or includes only the pre-processed rough and smooth surfaces. A titanium carbide coating treatment is performed by exposing to a high-temperature atmosphere of a mixed reaction gas containing titanium, hydrocarbons, and hydrogen for the required reaction time to stably form a pure titanium/carbide layer TiC of 5 to 20 microns on the smooth and rough surfaces. After the deposition coating, the surface of the pure titanium carbide TiC layer on the smooth surface is formed to a smoothness of 2 microns or less by appropriate smooth surface finishing means such as buff polishing and lap polishing.

In addition, the outer curled edge 1a of the can lid 1 and the outer periphery flange edge 2a of the can body 2 are press-fitted and seamed, which has a sensitive effect on the quality of the can container, requires the highest precision, and is most likely to wear out. Engagement of the seaming rolls 5 and 6 that contact the upper surface of the guide flange portion 4c of the seaming chuck 4 with the annular groove portions 5a and 6a provided around the outer periphery of the primary seaming roll 5 and the secondary seaming roll 6, respectively. After grinding, the upper surfaces of the grooves 5b and 6b are subjected to smooth surface preliminary processing such as lap polishing and buff polishing to form a smooth surface, and then the seaming rolls 5 and 6 are applied only to or including the smooth surface. The same titanium carbide coating treatment as described above is applied to the entire surface, and a pure titanium carbide layer TiC of 5 to 20 microns is stably deposited and coated on the smooth surface, and then a pure titanium carbide layer TiC is coated on the smooth surface.
The surface is formed to a smoothness of about 0.05 to 2 microns by suitable smooth finishing means such as lap polishing and buff polishing.

The upper surface of the guide flange portion 4c of the seaming chuck 4 and the engagement groove 5 between the seaming rolls 5 and 6
If the upper surfaces of b and 6b are pre-processed to have a smooth surface and finished with a smooth surface after being coated with titanium carbide, the seaming rolls 5 and 6 will fall downward under their own weight when the cans are not fed and idle, and as a result, the seaming rolls 5 and 6 will be lowered by their own weight.
The upper surface of the engagement grooves 5b and 6b and the seaming chuck 4
Although the upper surfaces of the guide flange portions 4c of the guide flange portions 4c rotate idly in a state in which they are in contact with each other, it also has the effect of preventing wear of both at this time. Further, even if the upper surface of the guide flange portion 4c of the seaming chuck 4 is not coated with titanium carbide, wear can be similarly prevented by smoothing the upper surface of the guide flange portion 4c (see FIG. 5). Incidentally, when the can is fed and the lid is tightened, the engagement groove of the seaming roll and the guide flange of the seaming chuck are not in contact with each other.

Furthermore, after grinding the upper surface of the lifter plate 3, which is most likely to be worn out due to the friction between the can body 2 placed on top and the can bottom 2b during loading and unloading, preliminary smooth surface treatments such as lap polishing and buff polishing are performed. Then, the same titanium carbide coating treatment as described above is applied to only the smooth surface or the entire lifter plate 3 including the smooth surface, and a pure titanium carbide of 5 to 20 microns is coated on the smooth surface. After stably depositing and coating the bite layer TiC, the surface of the pure titanium/carbide TiC layer on the smooth surface is subjected to appropriate smooth surface finishing processing methods such as lap polishing and buff polishing.
It is formed to have a smoothness of about 0.05 to 2 microns.

In addition, 7 in the figure is attached to the lower end of a knock out rod 9 which vertically and slidably passes through the rotary tube 8 to which the seaming chuck 4 is screwed. Knockout pad that moves up and down from inside part 4b, 10,1
1 and 12 are bearings.

Since the present invention is configured as described above, even if the seaming roll is not subjected to smooth surface finishing after titanium carbide coating treatment, the durability of the seaming roll with surface hardening is 3 to 19 times longer than that without surface hardening. In the case of lifter plates, those with surface hardening have approximately five times the durability compared to those without surface hardening, and those with a smooth surface finish after titanium carbide coating have an even greater durability. Extended.

In addition, by using martensitic stainless steel with high quench hardness as the base material in the quenching heat treatment, which is essential as a preliminary treatment to the titanium carbide coating process in manufacturing the can lid tightening tool A of the present invention, the titanium carbide coating process precipitates and coats the can lid tightening tool A of the present invention. The pure titanium/carbide layer TiC adheres well and stably to the base metal surface without fear of peeling, and martensitic stainless steel also has viscosity.
It also has the effect of eliminating the cracking phenomenon that has frequently occurred in the past on the seaming chuck 4, which is subjected to repeated impact loads by the seaming rolls 5 and 6.

In this way, the can lid tightening tool A of the present invention has ultra-high hardness by applying titanium carbide coating to at least the outer surface area that is most likely to wear, and furthermore, it has been subjected to smooth surface finishing after the titanium carbide coating process. This dramatically improves wear resistance and durability, resulting in a long service life, which means fewer tool changes, which can increase operating rates, and significantly improve tool management for maintenance, inspection and maintenance, and production work management. The surface hardening layer is simplified and smooth-finished during the seaming process, so there is no adverse effect from scratches or heat generation, and it satisfies the demands for high quality cans and high-speed mass production.

On the other hand, in order to increase the friction coefficient of the pure titanium/carbide layer TiC, which is the surface hardening layer, and to exhibit better braking function, the outer circumferential surface _4a1 of the lip of the seaming chuck is roughened and tightened. This prevents slippage between the inner circumferential surface 1b of the can lid and the outer circumferential surface _4a1 of the lip portion 4a of the seaming chuck 4, which improves the seaming accuracy and improves sealing performance to ensure perfect quality stability. The upper surface of the guide flange portion 4c of the seaming chuck 4, the annular groove portions 5a and 6a of the seaming rolls 5 and 6, the upper surface of the engagement grooves 5b and 6b of the seaming rolls 5 and 6, and the upper surface of the lifter plate 3 are subjected to smooth preliminary processing and Since the smooth surface has been processed, the coefficient of friction of the pure titanium/carbide layer TiC itself is further reduced, reducing the degree of wear to the highest possible extent and achieving excellent effects such as dramatically achieving a long life.

In the embodiments of the present invention, the seaming chuck, roll, and lifter are smooth-finished at the necessary locations, but of course, the necessary locations may be selectively combined or otherwise modified within the scope of the spirit of the present invention. Of course, it is within the spirit of the present invention to perform finishing work on necessary parts of the material as needed.

[Brief explanation of drawings]

Figures 1 to 4 are explanatory diagrams of a series of prescribed step-by-step processing by the can lid seaming tool, and Figure 5 is the can lid seaming tool of the present invention when no cans are being supplied, and the seaming process with which it is attached. FIG. 3 is a central vertical sectional view of the head. A...Can lid tightening tool, 1...Can lid, 1a...Outer curled edge, 1b...Inner circumferential surface, 2...Can body, 2a...Outer periphery flange edge, 3...Lifter plate, 4...Seaming chuck, 4a... Lip part, 4c...Guide flange part, 5...Primary seaming roll, 5a, 6a...
Ring groove part, 6...secondary seaming roll, TiC...pure titanium carbide layer.

Claims (1)

[Claims] 1. The base material of the seaming roll and lifter plate provided in the seaming tool is made of tough and corrosion-resistant martensitic stainless steel, and the can lid outer periphery curled edge and the can body outer periphery flange edge are polymerized. At least the annular groove of the seaming roll, which is press-fitted and tightened, and at least the upper surface of the lifter plate, on which the outer bottom surface of the can body is placed, are provided with a sliding surface on each of the outer surfaces thereof to improve the adhesion with the titanium carbide coating layer and prevent it from falling off. After pre-processing the surface and applying titanium carbide coating on it to harden the surface and add wear resistance to the toughness of the base material, at least one of the seaming rolls that has been coated with titanium carbide is One or two surfaces of the annular groove portion and the titanium carbide coating layer on at least the upper surface of the lifter plate are polished by appropriate processing means such as lap polishing or buff polishing.
The titanium carbide coating layer is finished to a smoothness of less than a micron, and during a series of seaming operations, rust and scratches occur on the outer curled edge of the can lid, the outer flange edge of the can body, and the outer bottom surface of the can body. A can lid tightening tool designed to prevent corrosion. 2 The base material of the seaming chuck, seaming roll, and lifter plate provided in the seaming tool is made of tough and corrosion-resistant martensitic stainless steel, and the seaming chuck that fits into the inner peripheral surface of the can lid At least the upper surface of the guide flange portion that engages with the engagement groove of the seaming roll, at least the annular groove portion of the seaming roll that press-fits and tightens the outer peripheral curled edge of the can lid and the outer peripheral flange edge of the can body that are crowned and overlapped, and the guide flange At least the upper surface of the engagement groove of the seaming roll that contacts the upper surface of the can body, and at least the upper surface of the lifter plate that rests the outer bottom surface of the can body, have good adhesion with the titanium carbide coating layer and prevent them from falling off. A smooth surface pre-processing and a rough surface pre-processing that can prevent slipping are applied to at least the outer peripheral surface of the lip portion of the seaming chuck, and a titanium carbide coating treatment is applied thereon to harden the surface and make it resistant to wear. After adding toughness to the toughness of the base material,
Any one of the titanium carbide coating layers on at least the upper surface of the guide flange portion of the seaming chuck, at least the upper surface of the annular groove and the engagement groove of the seaming roll, and at least the upper surface of the lifter plate among the titanium carbide coated parts. The outer circumference of the can lid is curled by the titanium carbide coating layer during a series of seaming operations. and a can lid tightening tool for preventing scratches caused by rust on the outer flange edge of the can body and the outer bottom surface of the can body.