JP2016120920A - Lug top plate for open pail can - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lug top plate for an open pail can capable of obtaining extremely high sealing performance to surely satisfy the regulation of a container grade II according to a dangerous article shipping and storage rule only by sealing and fixing to a can body through only caulking of a lug claw as in the conventional case.SOLUTION: A lug top plate for an open pail can includes an outermost peripheral fitting projected part 11 made of a steel plate having a thickness of 0.45 to 0.55 mm and configured to fit a lower surface side as a gasket storage groove 10 around the opening edge part of a can body, an annular recessed part 12 continuous over the entire circumference inside the fitting projected part 11, and an annular raised part 13 continuous over the entire circumference inside the annular recessed part 12 and chevron-shaped in longitudinal section. In the fitting projected part 11, a lug claw 4 is vertically drooped along an outer peripheral side wall 11a, a height from the annular recessed part 12 is set to 16 to 22 mm, and the height of the annular raised part 13 is set lower than that of the fitting projected part 11.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a rug top plate used for a metal open pail can mainly containing liquid products such as fuel oil, lubricating oil, paint, ink, solvent, adhesive, and cooking oil.

  Generally, a metal open pail can is a lug type that is sealed and fixed to a substantially vertical cylindrical can body that opens upward through a lug claw provided with a substantially disc-shaped top plate at the periphery. And a band-type type in which a fastening band having an open annular shape and a U-shaped cross-section is wound around the fitting peripheral edge portion of the top plate and the can main body and sealed and fixed.

  The conventional general-purpose lag type open pail can has a curled portion with the peripheral edge of the upper end opening of the can body being outwardly bent, while the top plate, that is, the outermost peripheral portion of the rug top plate, has a packing arrangement groove on the lower surface side. A number of tongue-shaped lug claws (in general, a large number of 16 pieces) are provided on the outer peripheral wall of the fitting convex portion over the entire circumference. The lug top plate is fitted to the opening curled opening edge of the can body through the packing having the fitting convex portion arranged in the packing arrangement groove, and each lug claw is crimped to the lower side of the opening edge. Are attached and secured to the can body (FIG. 6 of Patent Document 1 and FIG. 4 of Patent Document 2). In addition, each lug claw is caused from the folded state with an appropriate hand tool when removing the top plate. Therefore, a lug hole is provided in the center for easy operation, and the lower edge is curled into a thin cylindrical shape. Often. Further, the lug top plate is generally provided with a spout with a tongue fitted with a cap.

  In addition, as open pail cans, there are various sizes within a capacity range of 12 to 30 L, but 18 L cans and 20 L cans are widely used, and these two types of cans occupy most of the demand. . Steel plates (tin-free steel) are usually used for the can body and top plate, but in the case of 18L cans and 20L cans, the plate thickness is about 0.4 mm at the body (body) of the can body. The bottom plate) and the top plate are about 0.5 mm. And in the conventional lug top plate, it was common to set the height from the top plate main surface of the outermost fitting convex part to about 10 mm.

  However, in an open pail can that contains a dangerous liquid, it is an absolute objection to the occurrence of liquid leakage, and a high sealing performance is required. Particularly recently, open pail cans loaded for import and export are required to satisfy the provisions of the drop test as container class II in the Ministry of Land, Infrastructure, Transport and Tourism, Transport of Dangerous Goods Shipment and Storage Regulations / UN (UN). However, the conventional general specification cannot be used. In this drop test, the drop height is defined as 0.8 m for container class III when the transport material has a specific gravity of 1.2 or less, 1.2 m for container class II, and when the specific gravity exceeds 1.2. The specific gravity of container grade III is 0.67 (m), whereas the specific gravity of container grade II is 1.0 (m), which is stricter in each stage. It was. In addition, as a basic dropping method in the drop test, a chimney (a portion where the top plate is wrapped around the can body) is a diagonal drop with the impact point, a horizontal drop where the can body is dropped sideways, and the top plate side is down. There are three types of vertical drop that fall, but in particular, diagonal drop is likely to cause sealing failure due to deformation of the top plate periphery.

  On the other hand, as means for increasing the sealing strength, it is conceivable to increase the plate thickness of the can body and the top plate, or to use a high-tensile material for the plate material. The processing equipment must be modified to a high-capacity one, and it is not feasible from an economic point of view. In particular, it is difficult to raise the lug claw when opening the rug top plate, and it takes a lot of effort to operate it. A special tool is also required. In addition, in a lug-type open pail can, in order to increase the sealing strength, the fitting protrusion on the periphery of the top plate is fitted to the curl portion of the can body, and the lug claw is crimped. There is a method in which the portion is sandwiched between a reinforcing ring having an approximately U-shaped inner cross section and a band having an approximately U-shaped outer cross section (Patent Document 3), but two members, a reinforcing ring and a band, are separately required. Therefore, in addition to losing the advantages as an inexpensive lug type, there is a problem that workability is deteriorated because it takes time to install and remove the lug top plate.

JP2011-148520A (FIG. 6) JP 2012-236632 A (FIG. 4) JP-A-9-309551

  In view of the above-described circumstances, the present invention provides a lug claw for a can body as in the past without increasing the plate thickness and without using a tightening band or other interposition member as a rug top plate for an open pail can. It is possible to obtain a very high sealing performance that can reliably meet the requirements of the drop test of the container class II of the dangerous goods ship transportation and storage regulations by simply sealing and fixing only, and also existing in the can manufacturing process. The object is to provide equipment that can be used with almost no modification to the equipment.

  If the problem-solving means of the present invention is shown with reference numerals in the drawings, the invention of claim 1 covers the substantially vertical cylindrical can body 2 in a metal open pail can through a packing 3 and the periphery thereof. A rug top plate 1 that is fixed to the can body 2 in a sealed state by folding a large number of hanging lug claws 4 to the lower side of the outwardly curled opening edge 2a of the can body 2, The outermost fitting convex part 11 which is made of a steel plate having a thickness of 0.50 to 0.55 mm and is externally fitted to the opening edge part 21 of the can body 2 with the lower surface side as the packing accommodating groove 10, and the fitting convex part 11 The annular concave portion 12 that is continuous over the entire circumference inside the annular concave portion 12 and the annular ridge portion 13 that has a mountain-shaped longitudinal section that is continuous over the entire circumference inside the annular concave portion 12, and the fitting convex portion 11 extends along the outer peripheral side wall 11 a. While the lug claw 4 is suspended, the height h1 from the annular recess 12 is 1. Is set to ～22Mm, height h2 of the annular ridge 13 is characterized in that it is set lower than the fitting convex portion 11.

  The invention according to claim 2 is the open pail can lug top plate according to claim 1, wherein the annular recess 12 has a width W2 of 8 to 16 mm and a minimum height of ± 2 mm with respect to the top plate main surface 1a. The annular ridge 13 has a width W3 of 15 to 20 mm and a height h2 with respect to the top plate main surface 1a of 6 to 10 mm.

  The invention according to claim 3 is the open pail can lug top plate according to claim 1 or 2, wherein the outer peripheral slope 13a of the annular ridge 13 is set to be steeper than the inner peripheral slope 13b. An annular bead 14 having a shallow ridge or a low ridge having a width W4: 4 to 10 mm is provided at an interval d of 10 to 25 mm inward from the ridge 13.

  According to a fourth aspect of the present invention, in the open pail can lug top plate according to any one of the first to third aspects, the number of lug claws 4 is 21.

  A fifth aspect of the present invention is the open pail can lug top plate according to any one of the first to fourth aspects, wherein the can body is made of a steel plate having a capacity of 18L or 20L and a body portion 21 having a thickness of 0.40 to 0.50 mm. 2 is applied.

  The effects of the present invention will be described below with reference numerals in the drawings. First, in the open pail can lug top plate 1 according to the first aspect of the invention, the outermost fitting projection 11 that covers the outwardly curled opening edge 21 of the can body 2 via the packing 3 The annular recess 12 protrudes high in a specific range, and the annular recess 12 has an annular raised portion 13 having a longitudinal cross-sectional shape continuous over the entire circumference. When the sealed open pail can is dropped diagonally from a high place, the drop impact causes deformation around the top plate, but below the top chime 5 that winds up the opening edge 2a of the can body 2 A side portion, that is, a long constricted portion 6 in which the inner peripheral side wall 11b of the fitting convex portion 11, the body portion 21 of the can body 2 and the lug claw 4 overlap is greatly bent and deformed inwardly to absorb the shock, Because the chime 5 itself needs only a little deformation There is no damage to the seal, and the deformation of the chime 5 is reduced due to the shock absorbing action at the constricted portion 6 even in horizontal and vertical drops, and the container class II of the aforementioned dangerous goods ship transport and storage regulations is specified. An extremely high sealing strength that can be reliably satisfied is obtained.

  When this lug top plate 1 is used, the outermost fitting projection 11 is fitted to the curled opening edge 2 a of the can body 2 via the packing 3 in the same manner as a conventional general lug top plate. Then, each lug claw 4 can be fixed by being fastened to the can body 2 by crimping and folding the lug claw 4 to the lower side of the opening edge 2a, and there is no need to use a tightening band or other intervening members. The thickness of the steel plate of the top plate 1 is equivalent to the conventional one, and it is not necessary to increase the plate thickness of the can body 2 to be applied, so there is an advantage that the existing equipment in the can making process can be used with almost no modification. .

  According to the invention of claim 2, the width of the annular recess 12 in the lug top plate 1 and the height of the lowest portion with respect to the top plate main surface 1a, and the width of the annular raised portion 13 and the height with respect to the top plate main surface 1a are specified. Therefore, the rigidity of the inner portion from the annular ridge 13 of the lug top plate 1 is increased, and the deformation due to the above-described diagonal drop, horizontal drop, and vertical drop impact is difficult to reach the center of the top plate, The stopping strength is further improved.

  According to the invention of claim 3, the outer peripheral slope 13 a of the annular ridge 13 in the lug top plate 1 is steeper than the inner peripheral slope 13 b and is spaced apart within a specific range inside the annular ridge 13. Since it has the annular bead 14 of a specific width, the inner part becomes more rigid from the annular ridge 13 of the lug top plate 1, and the sealing strength is further improved.

  According to the invention of claim 4, since the lug top plate 1 has the 21 lug claws 22 that are multiples of 3, a high sealing strength can be secured while avoiding an increase in material cost and weight.

  According to the invention of claim 5, the lug top plate 1 capable of exhibiting extremely excellent sealing performance can be provided as a general-purpose open pail can having a capacity of 18L or 20L.

1 is a perspective view of an entire open pail can with a rug top plate of the present invention. The lug top plate is shown, (a) is a plan view and (b) is a side view. It is arrow sectional drawing of the XX line of Fig.2 (a). It is a top view which shows the flat half part in the step punched from the original plate in manufacture of the lug top plate. It is a vertical side view of the fitting part of the lug top plate and the can body. The deformation | transformation state by the fall of the fitting part is shown, (a) is a longitudinal side view after diagonal fall, (b) after horizontal fall, and (c) after vertical fall, respectively. The state after the drop test of the open pail can is shown, (a) is a photograph after diagonal drop, and (b) is a photograph after horizontal drop.

  Hereinafter, an embodiment of a rug top plate for an open pail can according to the present invention will be specifically described with reference to the drawings.

  The open pail can shown in FIG. 1 is a general-purpose type having a capacity of 18L or 20L, and the substantially disc-shaped lug top plate 1 of the present invention is fitted to the substantially vertical cylindrical can body 2 opened upward, A large number of lug claws 4 provided on the periphery of the lug 4 are crimped and bent inward to fix the lug top plate 1 to the can body 2. Note that the lug top plate 1 may be provided with a spout 7 with a tongue 71 and a cap 72 as indicated by a virtual line.

  The can body 2 includes a body portion 21 having two upper and lower annular bead portions 21a and 21b that bulge outward in the circumferential direction toward the upper portion, and a disk-shaped ground plate that is fastened and fixed to the lower end thereof at the peripheral edge portion. As a T-type (tapered pail type) that can be nested and stacked in an empty state, the lower side of the lower annular bead part 21b in the body part 21 is reduced in diameter downward. In addition, a cap-shaped handle mounting bracket 23 called an ear (ear) is fixed to the can main body 2 on the slightly lower radial side of the upper annular bead portion 21a by spot welding or the like. A vine-shaped handle 8 made of a wire material curved in an arc shape is attached to the can body 2 so as to be vertically rotatable by inserting the hooks 8a at both ends into the handle mounting bracket 24. A cylindrical grip 81 made of wood or plastic is fitted in the part.

  In addition, the base plate 22 of the rug top plate 1 and the can body 2 is made of a steel plate (tin-free steel) having a thickness of 0.50 to 0.55 mm, and the body portion 21 of the can body 2 is 0.40 to 0.50 mm in thickness. Steel plate (same as above).

  As shown in FIG. 2 and FIG. 3, the lug top plate 1 before being attached to the can main body 2 has an outermost fitting convex portion 11 having a packing receiving groove 10 on the lower surface side, and the entire inner periphery thereof. An annular recess 12 that is continuous, an annular ridge 13 having a mountain-shaped longitudinal section that is continuous over the entire circumference inside the annular recess 12, and an annular bead 14 that forms a shallow groove that is spaced from the annular ridge 13 and provided inside. And concentrically. The outermost fitting projection 11 has a packing receiving groove 10 on the lower surface side, the packing 3 is loaded on the inner upper end, and each has a tongue-like shape having a hooking hole 4a along the outer peripheral side wall 11a. 21 lug claws 4 are suspended. In addition, 70 shown with a virtual line in Fig.2 (a) is a spout lower hole.

  Here, the fitting convex portion 11 has a height h1 from the inner annular concave portion 12 set to 16 to 22 mm, and its width W1 is an outwardly curled opening edge 2a (see FIG. 5)). Further, the annular recess 12 is inclined slightly lower toward the outer peripheral side, the width W2 is set to 8 to 16 mm, and the height of the lowest part is set to ± 2 mm with respect to the top plate main surface 1a. Further, the annular raised portion 13 has a height h2 of 6 to 10 mm and a width W3 of 15 to 20 mm with respect to the top plate main surface 1a, and the outer peripheral side inclined surface 13a is steeper than the inner peripheral side inclined surface 13b. Is set.

  In order to manufacture such a lug top plate 1, a punching plate P having a peripheral lug claw 4 and a hanging hole 4a and, if necessary, a spout lower hole 70 as shown in FIG. The punching plate P is pressed to form the fitting convex portion 11, the annular concave portion 12, the annular raised portion 13, the annular bead 14, and if necessary, the concavity and convexity for fitting the base of the spout 7 (not shown). do it. In addition, since the height h1 of the fitting convex part 11 is as high as 16-22 mm, the said press work becomes what is called a deep drawing process.

  In order to attach the lug top plate 1 to the can body 2, as shown in FIG. 5, the outermost fitting projection 21 is inserted through the inner packing 3 as in the conventional general lug top plate. Can be fitted to the opening edge 2a of the can body 2 and each lug claw 22 can be crimped to the lower side of the opening edge 2a and folded, but the fitting protrusion 11 is higher than the inner annular recess 12. By projecting, the fitting protrusion 11 lowers the chime 5 at the top of the can body 2 and tightens the opening edge 2 a of the can body 2, that is, the inner peripheral side wall 11 b of the fitting protrusion 11. The overlapping portion of the body portion 21 of the can body 2 and the lug claw 4 forms a constricted portion 6 that is long in the vertical direction.

  Thus, in the open pail can in which the rug top plate 1 is attached and fixed, when the chime 5 is dropped from a high position so as to collide with the drop surface while containing the liquid product, Although it is inevitable that the fitting portion with the can body 2 is deformed, as shown in FIGS. 6A to 6C, the long constricted portion 6 below the chime 5 is deformed to absorb the impact. In addition, since the lug top plate 1 is difficult to deform in the radial direction by having the annular raised portion 13 inside the fitting convex portion 21, the top chime 5 itself is only slightly deformed and does not cause a sealing failure. Therefore, an extremely high sealing strength that can surely satisfy the provisions of the container class II of the aforementioned dangerous goods shipping and storage regulations is obtained.

  In a diagonal drop with the chime 5 as the impact point (falling in a slanted position with the top side down), the periphery of the lug top 1 is slanted around the collision part as shown in FIG. Although the constricted portion 6 is greatly deformed by bending inwardly, the chime 5 is slightly flattened on the top of the fitting convex portion 11 of the lug top plate 1 around the impact point and outwards. It is a grade which inclines, and the sealing state by winding of this chime 5 is maintained. Further, in the horizontal drop (falling the can in a horizontal posture), as shown in FIG. 6B, the collision side of the body portion 21 of the can main body 2 is generally recessed so as to be flattened, and at the same time the collision side of the chime 5 Is also deformed from a circular arc shape in plan view to a substantially straight line shape in plan view along the recess of the can body 2, but the deformation is concomitant with a decrease in the width of the annular concave portion 12 of the lug top plate 1 and an extension of the fitting convex portion 11. The chime 5 itself is maintained in a sealed state to such an extent that the bulge on the outer peripheral side is flattened. Further, in vertical drop (falling in an inverted posture with the top side facing down), as shown in FIG. 6 (c), the constricted portion 6 is largely bent inward except for the lug claw 4, so that the chime 5 However, the chime 5 itself maintains the sealed state to such an extent that the top of the fitting convex portion 11 of the lug top plate 1 is flattened by collision with the dropping surface.

  In the lug top plate 1 of the present invention, as described above, in order to provide the excellent sealing performance of the open pail can, the outermost fitting convex portion 11 to be fitted to the opening edge 2a of the can body 2 can be used. It has a height of 16 mm or more with respect to the inner annular recess 12, has an annular ridge 13 having a mountain-shaped longitudinal section that continues throughout the entire circumference inside the annular recess 12, and the annular ridge 13 is a fitting projection. Both lower than 11 and the thickness of the steel sheet being in the range of 0.50 to 0.55 mm are important.

  That is, when the height of the fitting convex portion 11 is less than 16 mm, the constricted portion 6 below the chime 5 is shortened, so that the open pail can is dropped in various postures in which the chime 5 collides with the dropping surface. At this time, the effect of absorbing the drop impact by the constricted portion 6 becomes insufficient, and the chime 5 is greatly deformed by the drop impact, resulting in a sealing failure. It should be noted that even if the height of the fitting convex portion 11 exceeds the upper limit of 22 mm, there is no problem in sealing performance. However, the size of the original plate P used for the lug top plate 1 is increased and the material cost is increased. The depth of fitting of the lug top plate 1 with respect to the can body 2 becomes deep and it becomes difficult to secure a predetermined can volume, and in order to avoid this, increasing the height of the body portion 21 of the can body 1 is a material cost. In addition to the increase, it is necessary to change various apparatus specifications in the manufacturing process of the can body 1 according to the size, which is unrealistic from the viewpoint of equipment cost.

  On the other hand, since the rigidity of the lug top plate 1 is increased at the inner portion of the annular recess 12 at the inner portion of the annular recess 12, the deformation when a drop impact is applied is less likely to extend inward than the annular protrusion 13. The constricted portion 6 on the outer peripheral side is greatly deformed including the annular concave portion 12, and the drop impact is efficiently absorbed. Further, when the height of the annular raised portion 13 is higher than the outermost fitting projection 11, the vertical drop or the drop impact in a can posture close to it is directly received, and the diagonal drop or horizontal drop At this time, the deformation is performed so that the width is reduced by an impact, and accordingly, the fitting convex portion 11 on the outer peripheral side is pulled inward, so that it is easy to cause a distorted deformation that leads to a sealing failure of the chime 5. In addition, although it does not specifically limit as this cyclic | annular protruding part 13, In order to ensure the said rigidity and to suppress the deformation | transformation of itself, as above-mentioned, height H2 with respect to the top-plate main surface 1a is 6-10 mm. The width W3 is preferably 15 to 20 mm. Further, by making the outer peripheral slope 13a of the annular ridge portion 13 steeper than the inner peripheral slope 13b, the outer peripheral edge portion of the annular ridge portion 13 becomes more rigid. Can be more effectively suppressed.

  When the thickness of the steel plate forming the lug top plate 1 is less than 0.50 mm, the strength is insufficient. On the other hand, when the thickness exceeds 0.55 mm, the constricted portion 6 is difficult to deform, and the effect of absorbing the drop impact is insufficient. In addition, the material cost is high. Further, since the range of the plate thickness is the same as that of the conventional one, there is an advantage that the existing equipment can be used with almost no modification to manufacture the lug top plate 1.

  The number of lug claws 22 on the rug top plate 1 is not particularly limited. However, when the number of lug claws 22 is set to 21 which is a multiple of 3, the engagement strength is greater than the case of more than 22 or less than 20. It is preferable at the point obtained. The fact that the anchor strength increases by a multiple of 3 has not been theoretically sufficiently elucidated, but it is clear in terms of phenomena because comparative data with good reproducibility is obtained, and the same applies to the crown of the bottle lid. For the reason, the number of jaggedness is 21. Further, the lug claw 4 is not limited to the one having the hanging hole 4a and the lower edge portion being straight as illustrated, and the lug claw 4 having no hanging hole 4a or the lower edge portion being curled into a thin cylindrical shape. It may be a thing.

  In the rug top plate 1 exemplified as the embodiment, the annular bead 14 is provided on the inner side of the annular ridge 13 so as to form a shallow concave stripe. However, instead of this, an annular bead forming a low convex stripe may be provided. Good. Thus, such a shallow concave or low convex annular bead is not essential, but the advantage is that the inner portion of the lug top plate 1 is made to be more rigid and the sealing strength is further improved. There is. In addition, as the annular bead 14, the distance d from the annular ridge 13 shown in FIG. 3 is 10 to 25 mm, the width W4 is 4 to 10 mm, the depth at the concave stripe or the height at the convex stripe with respect to the top plate main surface 1a. Is preferably set to about 0.3 to 1.0 mm.

  Although it does not specifically limit about the plate | board thickness of the steel plate which the trunk | drum 21 of the can main body 2 forms, The range of 0.40-0.50mm is preferable, and while too thin can strength will be insufficient, As in the case of the lug top plate 1 described above, the constricted portion 6 is difficult to deform. Further, the ground plate 22 is preferably in the range of 0.45 to 0.55 mm in thickness as described above from the viewpoints of both strength and material cost. In addition, since the suitable range of the plate | board thickness of these trunk | drum 21 and the baseplate 22 is equivalent to the conventional one, there exists an advantage that it can utilize, without almost modifying the existing equipment in a can manufacturing process.

  As the can body 1 to which the lug top plate 1 of the present invention is applied, as illustrated in the embodiment, a T-type (tapered pail type) in which the lower side of the body part 21 is reduced in diameter, and the body part 21 is not reduced in diameter S. There is a type (straight type). In addition, the number and formation positions of the annular bead portions provided in the body portion 21 can be variously set.

[Drop test]
As a lug top plate for a 20L open pail can, the one with the following specifications in the configuration shown in FIG. 3 is used, and, as shown in FIG. An open pail can for testing was used. A total of 6 cans of this open pail, 2 cans for each drop method, and a container grade II drop test (drop height) stipulated by the Ministry of Land, Infrastructure, Transport and Tourism, Transport of Dangerous Goods and Storage Regulations / UN (UN) As a result, it was proved that all cans did not leak water in any of diagonal drop, horizontal drop and vertical drop, and had a very high sealing strength. The state after the diagonal drop of the test can is shown in FIG. 7A, and the state after the horizontal drop is shown in FIG.

<Rug top plate specification>
Plate material: Tin-free steel with a thickness of 0.5mm 4 lugs 4 ... 21 Upper surface diameter ... 300mm
Fitting projection 11... Height h1 = 19.0 mm, width W1 = 6.5 mm
Annular recess 12: width W2 = 9.5 mm, height of the lowest part = top plate main surface 1a-0.1 mm
Annular ridge 13... Height h2 = 7.2 mm, width W3 = 18.2 mm, angle of outer peripheral slope 13a = 60 °, angle of inner peripheral slope 13b = 45 °
Annular bead 14... Spacing d from annular ridge 13 = 14.6 mm, width W4 = 5.0 mm, depth to top plate main surface 1a = 0.6 mm

DESCRIPTION OF SYMBOLS 1 Lug top plate 1a Top plate main surface 10 Packing accommodation groove 11 Fitting convex part 11a Outer peripheral side wall 12 Annular recessed part 13 Annular protruding part 13a Outer peripheral side inclined surface 13b Inner peripheral side inclined surface 14 Annular bead 2 Can main body 2a Opening edge 3 Packing 21 Body part 4 Lug claw 3 Packing 5 Chime 6 Constricted part d Distance between annular raised part and annular bead h1 Height of fitting convex part from annular recessed part h2 Height of annular raised part W2 Width of annular recessed part W3 annular raised part Width W4 annular bead width

Claims (5)

A metal open pail can covered with a packing on a substantially vertical cylindrical can body, by folding a large number of lug claws suspended on the periphery to the lower side of the opening edge of the can body outwardly curled, A lug top plate that is sealed against the can body,
It is made of steel plate with a thickness of 0.50 to 0.55 mm, and the outermost fitting projection that is fitted on the opening edge of the can body with the lower surface side as the packing receiving groove, and the entire circumference inside the fitting projection An annular recess that extends continuously over the entire circumference inside the annular recess,
The fitting convex portion has the lug claw suspended along the outer peripheral side wall, and the height from the annular concave portion is set to 16 to 22 mm.
A rug top plate for an open pail can, wherein the height of the annular raised portion is set lower than the fitting convex portion.   The annular recess has a width of 8 to 16 mm and a minimum height of ± 2 mm with respect to the top plate main surface. The annular ridge has a width of 15 to 20 mm and a height of 6 to 10 mm with respect to the top plate main surface. The rug top for an open pail can according to claim 1 or 2.   The outer circumferential slope of the annular ridge is set to be steeper than the inner circumferential slope, and a shallow groove or a low convex with a width of 4 to 10 mm is spaced inwardly by 10 to 25 mm from the annular ridge. The open pail can lug top plate according to claim 1 or 2, comprising an annular bead forming a strip.   The number of the said lug claw is 21 pieces, The rug top plate for open pail cans in any one of Claims 1-3.   The rug top plate for an open pail can according to any one of claims 1 to 4, which is applied to a can body made of a steel plate having a capacity of 18L or 20L and a body portion of 0.40 to 0.50 mm in thickness.

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