Capping head, spindle assembly, capping device, and capping system

Abstract

Provided is a body (1) of a capping head (10), the body (1) being used in a capping head (10) that attaches a topped cylindrical cap to a mouthpiece of a can having a bottomed cylindrical shape. The body (1) comprises a cylindrical body main part (11), a spindle attachment section (15) that is disposed inside the body main part (11) and is attached to a spindle, and a swing shaft storage section (18) that is disposed between the outer periphery and inner periphery of the body main part (11). The swing shaft storage section (18) has a through-hole (23) disposed around the spindle attachment section (15), the through-hole (23) having inserted therethrough a swing shaft (3) that causes a forming roller (5) to swing toward the peripheral wall of the cap. The through-hole (23) passes vertically through the body main part (11).

Description

Technical Field

[0001] The present invention ,tree relates to a capping head, a spindle assembly, a capping device, and a capping system. This application claims priority to Japanese Patent Application No. 2022-134830 filed in Japan on August 26, 2022, and Japanese Patent Application No. 2022-135769 filed in Japan on August 29, 2022, the contents of which are incorporated herein by reference.

Background Art

[0002] Conventionally, a capping head for attaching a cap to the mouth part of a screw-on can filled with a content such as a beverage has been known (for example, Patent Document 1). The capping head of Patent Document 1 includes a body, a cam follower disposed above the body, a forming roller disposed below the body, a swing shaft connecting the cam follower and the forming roller, and a biasing member that biases the cam follower and the forming roller radially inward via the swing shaft. An intermediate portion of the swing shaft located between both upper and lower ends in the vertical direction, and the biasing member provided on this intermediate portion are disposed on the outer peripheral portion of the body and are exposed radially outward from the body.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the conventional capping head, the body has a complicated shape, and it is difficult to increase the strength of the body. Further, in order to ensure the strength of the body, it is necessary to use a high-rigidity material such as stainless steel, resulting in an increase in weight.

[0005] This invention allows for a simplified body shape, increased body strength, and weight reduction. Na Ki The objective is to provide capping heads, spindle assemblies, capping devices, and capping systems. [Means for solving the problem]

[0006] [Aspect 1 of the present invention] At the mouth of the bottomed cylindrical can, Top-shaped tubular Capping head to attach the cap Do There is, The capping head comprises a capping head body used in the capping head, a molding roller positioned below the body, a pivot shaft that pivots the molding roller toward the peripheral wall of the cap, a cam follower positioned above the body and engaging with a cam, and a biasing member that biases the cam follower and the molding roller radially inward via the pivot shaft, wherein the body is The device comprises a cylindrical body, a spindle mounting portion disposed inside the body and attached to a spindle, and a pivot shaft housing portion disposed between the outer and inner circumferences of the body, wherein the body is a single cylindrical body having a cylindrical outer surface, and the pivot shaft housing portion is disposed around the spindle mounting portion. The aforementioned The molding roller is swung toward the peripheral wall of the cap. The aforementioned It has a through hole through which a pivot shaft is inserted, and the through hole penetrates the body in the vertical direction. The body, the spindle mounting portion, and the oscillating shaft housing portion are connected to each other, the biasing member surrounds a portion of the oscillating shaft in the vertical direction around the axis of the oscillating shaft and is housed in the through hole, and the entire biasing member is housed in the through hole without being exposed on the outer circumference of the body. Capping Head Do. [Aspect 2 of the present invention] A capping head for attaching a top-cylindrical cap to the mouth of a bottom-cylindrical can, comprising: a capping head body used in the capping head; a molding roller positioned below the body; a pivot shaft for pivoting the molding roller toward the peripheral wall of the cap; a cam follower positioned above the body and engaging with a cam; and a biasing member for biasing the cam follower and the molding roller radially inward via the pivot shaft, wherein the body comprises a cylindrical body body, a spindle mounting portion positioned inside the body body and attached to a spindle, and a pivot shaft housing portion positioned between the outer and inner circumferences of the body body, wherein the body body is a single cylindrical body having a cylindrical outer surface, and the pivot shaft housing portion is positioned around the spindle mounting portion and pivots the molding roller toward the peripheral wall of the cap. A capping head having a through hole through which the pivot shaft is inserted, the through hole passing through the body in the vertical direction, the body, the spindle mounting portion and the pivot shaft housing portion being connected to each other, the biasing member surrounding a portion of the pivot shaft in the vertical direction around the axis of the pivot shaft and being housed in the through hole, the pivot shaft having a support shaft extending in the vertical direction, an upper arm connecting the support shaft and the cam follower, and a lower arm connecting the support shaft and the molding roller, the upper arm having an upper clamp portion that surrounds the support shaft around its axis and is deformable to press against the outer circumferential surface of the support shaft, the lower arm having a lower clamp portion that surrounds the support shaft around its axis and is deformable to press against the outer circumferential surface of the support shaft, and at least one of the upper clamp portion and the lower clamp portion having a deformation assist groove arranged on the circumferential surface of the clamp portion and extending in the vertical direction.

[0009] In this invention, the body has a cylindrical shape, and the external shape of the body is simply constructed. The body also has a through hole that penetrates the body vertically, and a pivot shaft that oscillates the molding roller is inserted through this through hole. The pivot shaft housing section, in which the through hole is provided, is arranged around the spindle mounting section. The capping head body of this invention has a simple structure consisting of a cylindrical body, a spindle mounting section that is attached to the spindle, and a pivot shaft housing section in which the through hole is located. As a result, the rigidity of the body is increased while keeping the body structure simple and avoiding complexity in the shape. In particular, the above effects are further enhanced when the body, spindle mounting section, and pivot shaft housing section are connected to each other.

[0010] Furthermore, cam followers and forming rollers are connected to both ends of the pivot shaft in the vertical direction, and the intermediate portion of the pivot shaft located between the two ends in the vertical direction, and a biasing member that is externally fitted to this intermediate portion, are housed in the through-hole of the body. The biasing member is provided so as to surround a part of the pivot shaft (the intermediate portion) around its axis and is housed in the through-hole.

[0011] According to the present invention, since a part of the pivot shaft (intermediate portion) and the biasing member (hereinafter referred to as the biasing member, etc.) are housed inside the body, there is no need for notches or recesses provided to expose the biasing member, etc. to the outer circumference of the body, as in the conventional invention. Therefore, the present invention makes it possible to construct the body in a simple shape, making it easy to manufacture. Furthermore, by simplifying the shape of the body, the strength of the body can be increased.

[0012] Furthermore, by housing the biasing members and the like within the body, it is possible to suppress the adhesion of contents such as beverages (especially sugars that tend to solidify) that are scattered from outside the body to the biasing members and the like. As a result, the performance (function) of the biasing members and the like can be maintained well over a long period of time, and maintenance is also easy.

[0013] Furthermore, by increasing the rigidity of the body, it becomes possible to construct the body from materials with a lower specific gravity compared to stainless steel, which was used to make up conventional bodies, such as aluminum alloys like duralumin, engineering plastics, and resin materials (including composite resin materials) like FRP (fiber-reinforced plastic). Therefore, it becomes easier to reduce the weight of the capping head. A preferred example of an engineering plastic is PEEK (polyetheretherketone).

[0014] Based on the above, the present invention no Ki The capping head, as well as the spindle assembly and capping device equipped therewith, allow for a simplified body shape, increased body strength, and reduced weight.

[0015] before The biasing member is entirely accommodated in the through-hole without being exposed to the outer peripheral portion of the body main body. ru.

[0016] In this case, the above-described operational effects obtained by accommodating the biasing member in the through-hole become more prominent. The pivot shaft comprises a support shaft extending in the vertical direction, an upper arm connecting the support shaft and the cam follower, and a lower arm connecting the support shaft and the molding roller. The upper arm has an upper clamp portion that surrounds the support shaft around its axis and is deformable to press against the outer circumferential surface of the support shaft. The lower arm has a lower clamp portion that surrounds the support shaft around its axis and is deformable to press against the outer circumferential surface of the support shaft. At least one of the upper clamp portion and the lower clamp portion has a deformation assist groove that is arranged on the circumferential surface of the clamp portion and extends in the vertical direction. In this case, a deformation assist groove extending in the vertical direction is provided on the circumferential surface (circumferential surface of the clamp) of the upper or lower clamp (hereinafter sometimes simply referred to as the clamp), making it easier for the clamp to deform in a direction that presses against the outer surface of the support shaft. This makes it possible to keep the outer diameter (diameter dimension) of the support shaft small (i.e., make the support shaft thinner), and accordingly, the outer diameter of the entire capping head can also be kept small, thus enabling further weight reduction.

[0017] 〔Aspect of the present invention 3 〕 A plurality of the through-holes are provided at intervals in the circumferential direction, each of the through-holes has an opening that opens to the upper end surface of the body main body, and a dimension along the circumferential direction of the opening becomes smaller as it goes toward the radially inner side. Aspect 1 Or 2 The capping head according to the description.

[0018] 〔Aspect of the present invention 4 〕 The opening has a triangular hole shape in a top view. Aspect 3 The capping head according to the description.

[0019] In this case, among the swing shaft accommodating portions, the circumferential dimension (i.e., the wall thickness dimension) of the portion (hereinafter referred to as the frame) located between the circumferentially adjacent through-holes becomes less likely to vary at each position in the radial direction, and the strength of the frame is stably increased. For this reason, it is possible to secure the strength of the body while suppressing the interval between the through-holes arranged in the circumferential direction to be small. Further compactification and weight reduction of the capping head can be achieved.

[0020] 〔Aspect of the present invention 5 〕 The body has a body recess that is recessed downward from the upper surface of the body and accommodates at least the lower end portion of the cam, and the radially inner end portion of the opening opens to the inner circumferential surface of the body recess. Aspect 3 The capping head according to the description.

[0021] In this case, at least the lower end of the cam is inserted into a body recess that opens on the upper surface of the body, allowing the cam and the body to be positioned closer together in the vertical direction. This reduces the vertical dimensions of the body, resulting in a more compact and lightweight design. Furthermore, the opening of the through-hole extends to the inner circumferential surface of the body recess, creating a large opening. Therefore, this opening also contributes to further weight reduction of the body.

[0022] [Aspects of the present invention] 6 ] The body comprises the body main body and an annular body flange fixed to the upper end of the body main body, the through hole comprises a body hole portion that penetrates the body main body vertically and a flange hole portion that penetrates the body flange vertically, and the biasing member is positioned in the body hole portion. 1 from 5 A capping head as described in one of the following.

[0023] In this case, the biasing member can be placed in the main body hole and the body flange can be fixed to the upper end of the main body, allowing the biasing member to be easily housed inside the body. This simplifies the manufacturing of the capping head.

[0024] [Aspects of the present invention] 7 ] The main body hole has a housing hole in which the biasing member is arranged and a bearing hole located at the lower end of the main body hole, and the pivot shaft is rotatably supported in the body via a pair of bearing members provided in the flange hole and the bearing hole. 6 The capping head described above.

[0025] In this case, the pivot shaft is stably supported by a pair of bearing members provided in a flange hole located at the upper end of the body and a bearing hole located at the lower end of the body, and positioned apart in the vertical direction.

[0026] [Aspects of the present invention]8 ] The biasing member is a torsion coil spring that extends spirally around the axis of the pivot shaft, and of the two ends of the biasing member in the vertical direction, the upper end is locked to the body flange and the lower end is locked to the pivot shaft. 6 or 7 The capping head described above.

[0027] With the above configuration, the biasing member can be easily assembled inside the body while applying the desired biasing force by locking the upper end of the biasing member to the body flange and the lower end to the pivot shaft.

[0028] [Aspects of the present invention] 9 ] Embodiments in which at least a portion of the body is made of aluminum alloy, engineering plastic, or FRP. 1 from 8 A capping head as described in one of the following.

[0029] In this case, while maintaining the rigidity of the body, it is possible to reduce the weight of the body compared to conventional bodies made of stainless steel, etc.

[0030] [Aspects of the present invention] 10 ] An embodiment comprising a pressure block positioned on the lower side of the body and pressing down on the top wall of the cap. 1 from 9 A capping head as described in one of the following.

[0031] [Aspects of the present invention] 11 ] The molding rollers are arranged in a circumferential direction and consist of six or more rollers, and each of the molding rollers includes a plurality of screw-forming rollers that form a screw portion on the circumferential wall of the cap that screws into the mouth portion, and at least one hem-forming roller that forms a hem around the lower end of the circumferential wall of the cap onto the mouth portion, wherein the number of screw-forming rollers is greater than the number of hem-forming rollers. 1 from 10 A capping head as described in one of the following.

[0032] As shown in the above configuration, a larger number of thread forming rollers allows for a lower forming load (pressing force) per roller. Therefore, even when the threaded can (can) is made thinner, deformation of the mouth portion associated with the thread forming process can be suppressed more stably.

[0033] [Aspects of the present invention] 12 ] The screw forming rollers that are adjacent to each other in the circumferential direction are offset from each other in the vertical direction, 11 The capping head described above.

[0034] In this case, the forming locations on the circumferential wall of the cap for adjacent thread forming rollers in the circumferential direction are shifted vertically, which suppresses defects such as excessive thread forming at the same location on the cap's circumferential wall (especially near the upper groove, which is the starting position of the thread). This suppresses variations in the thread forming amount at each position in the vertical direction, resulting in a more uniform thread forming amount in the vertical direction.

[0035] Furthermore, because adjacent screw forming rollers are offset vertically, they can be positioned closer together without interfering with each other. This makes it possible to keep the outer diameter of the capping head smaller, further reducing its size and weight.

[0036] [Aspects of the present invention] 13 ] The molding rollers are arranged in a plurality in the circumferential direction, the number of biasing members is the same as the number of molding rollers and they are arranged in a plurality in the circumferential direction, and the number of through holes is the same as the number of biasing members and they are arranged in a plurality in the circumferential direction, 1 from 12 A capping head as described in one of the following.

[0037] In this case, each biasing member can be accommodated in each through-hole. That is, one biasing member can be placed in each through-hole. Therefore, the through-holes can be constructed simply, making the body easier to manufacture and increasing its rigidity.

[0040] [Aspects of the present invention] 14 ] manner 1 from 13 A spindle assembly comprising: a capping head as described in any one of the above; a lifting shaft extending vertically and to which a pressure block that presses against the top wall of the cap is attached; a cylindrical spindle into which the lifting shaft is inserted and to which the body is attached; and a cylindrical lifting cylinder into which the lifting shaft and the spindle are inserted, wherein the lifting shaft has an upper cam follower that moves the lifting shaft vertically; the spindle has a spindle gear that rotates the spindle around a central axis; and the lifting cylinder has a cylindrical cam and a lower cam follower that moves the lifting cylinder vertically.

[0041] [Aspects of the present invention] 15 ] A turret that rotates around a turret axis, and an embodiment that is positioned on the outer circumference of the turret. 14 A capping device comprising: a spindle assembly as described above; a fixed gear that meshes with the spindle gear and extends around the turret axis; an upper cam that extends around the turret axis and engages with the upper cam follower; and a lower cam that extends around the turret axis and engages with the lower cam follower.

[0042] [Aspects of the present invention] 16 ] A configuration comprising a filler for filling cans with contents and a can supplied after being discharged from the filler. 15 A capping system comprising the capping device described in [reference], wherein the direction of transport of the can discharged from the filler toward the capping device extends along the tangent to the outer circumference of the turret when viewed from the turret axis direction.

[0043] According to the capping system of the present invention, cans discharged from the filler are smoothly supplied to the capping device without their direction of transport being abruptly changed, that is, they are less affected by centrifugal force. As a result, the capping processing speed can be stably increased, and production efficiency can be further improved.

[0044] Furthermore, Japanese Patent Publication No. 2003-146392 (hereinafter referred to as Known Document 1) is known as a conventional capping head. This capping head of Known Document 1 is equipped with five or six forming rollers. By providing so many forming rollers, the forming load (pressing force) per forming roller can be kept small, making it easier to suppress deformation of the mouth portion even when the wall of a screw-top can is made thinner.

[0045] However, increasing the number of molding rollers also increases the external dimensions (and so on) and weight of the capping head. Therefore, it is difficult to improve production efficiency by increasing the capping processing speed.

[0046] One of the objectives (and another objective) of the present invention is to provide a capping head, spindle assembly, capping device, and capping system that can reduce weight by keeping the external dimensions of the capping head compact, and that can improve production efficiency by increasing the capping processing speed.

[0047] [Aspects of the present invention] 17 ] A capping head for attaching a top-cylindrical cap to the mouthpiece of a bottom-cylindrical screw-top can, comprising: a body centered on a central axis extending vertically; a cam follower positioned above the body and rolling on the outer circumferential surface of a cone cam; a forming roller positioned below the body and connected to the cam follower, moving radially with the radial movement of the cam follower; and a biasing member that biases the cam follower and the forming roller radially inward, wherein a plurality of cam followers are provided in a circumferential direction, and the same number of forming rollers as the cam followers are provided in a circumferential direction, the plurality of forming rollers include a plurality of screw forming rollers that form a threaded portion on the circumferential wall of the cap that screws into the mouthpiece, and at least one hem forming roller that forms a hem around the lower end of the circumferential wall of the cap onto the mouthpiece, and the body has a body recess that is recessed downward from the upper surface of the body and accommodates at least the lower end of the cone cam.

[0048] [Aspects of the present invention] 18 ] The inner diameter of the body recess is larger than the outer diameter of the lower end of the cone cam that contacts the cam follower. 17 The capping head described above.

[0049] [Aspects of the present invention] 19 ] The body has a spindle mounting portion which is attached to a spindle inserted inside the cone cam, and the spindle mounting portion is positioned at the bottom of the body recess which has a bottomed hole shape. 17 or 18 The capping head described above.

[0050] [Aspects of the present invention] 20 ] The inner diameter of the body recess is larger than the diameter of the spindle mounting portion, 19 The capping head described above.

[0051] [Aspects of the present invention] 21 ] The vertical dimension of the cone cam from the upper end position to the lower end position where the cam follower makes contact is defined as the molding dimension H, and the vertical depth dimension h of the body recess is 1.58H or less. 17 from 20 A capping head as described in one of the following.

[0052] [Aspects of the present invention] 22 ] The cam follower comprises a shaft portion extending in the vertical direction and a rolling element rotatably supported at the lower end of the shaft portion and pressed against the outer surface of the cone cam by the biasing force of the biasing member, 17 from 21 A capping head as described in one of the following.

[0053] [Aspects of the present invention] 23 ] An embodiment comprising a pressure block positioned on the lower side of the body and pressing down on the top wall of the cap. 17 from 22 A capping head as described in one of the following.

[0054] [Aspects of the present invention] 24 ] The molding rollers are provided in six or more configurations, and the number of screw molding rollers is greater than the number of hem-rolling rollers. 17 from 23 A capping head as described in one of the following.

[0055] [Aspects of the present invention] 25 ] The screw forming roller is provided in four units, and the hem rolling roller is provided in two units. 24 The capping head described above.

[0056] [Aspects of the present invention] 26 ] The screw forming rollers that are adjacent to each other in the circumferential direction are offset from each other in the vertical direction, 17 from 25 A capping head as described in one of the following.

[0057] [Aspects of the present invention] 27 ] The body has a spindle mounting portion that is attached to a spindle inserted inside the cone cam, and the spindle mounting portion is positioned to overlap with the body recess when viewed from the radial direction. 17 from 26 A capping head as described in one of the following.

[0058] [Aspects of the present invention] 28 ] The number of biasing members is the same as the number of cam followers and is arranged in a plurality in the circumferential direction, the body has biasing member housing holes extending in the vertical direction, the number of biasing member housing holes is the same as the number of biasing members and is arranged in a plurality in the circumferential direction, and each biasing member is housed in each biasing member housing hole, 17 from 27 A capping head as described in one of the following.

[0059] [Aspects of the present invention] 29 ] The biasing members are arranged in the same number as the cam followers and are provided in multiples in the circumferential direction, the body has concave pockets that are recessed radially inward from the outer circumferential surface of the body and extend vertically, the same number as the biasing members and are provided in multiples in the circumferential direction, each biasing member is housed in each of the pockets, and the body is provided with a cylindrical cover that surrounds the body from the radially outside to the entire circumference in the circumferential direction, 17 from 27 A capping head as described in one of the following.

[0060] [Aspects of the present invention] 30 ] The body is made of aluminum alloy, 17 from 29 A capping head as described in one of the following.

[0061] [Aspects of the present invention] 31 ] An embodiment comprising a pressure block positioned below the body and pressing against the top wall of the cap, wherein the body has a housing cylinder protruding downward from the lower surface of the body, and a portion of the pressure block is housed in the housing cylinder. 17 from 30 A capping head as described in one of the following.

[0062] [Aspects of the present invention] 32 ] The cam follower and the molding roller are supported by a support member, the support member having a support shaft extending in the vertical direction, an upper arm connecting the support shaft and the cam follower, and a lower arm connecting the support shaft and the molding roller, the upper arm having an upper clamp portion that surrounds the support shaft around its axis and is deformable to press against the outer circumferential surface of the support shaft, the lower arm having a lower clamp portion that surrounds the support shaft around its axis and is deformable to press against the outer circumferential surface of the support shaft, and at least one of the upper clamp portion and the lower clamp portion has a deformation assist groove that is arranged on the circumferential surface of the clamp portion and extends in the vertical direction, 17 from 31 A capping head as described in one of the following.

[0063] [Aspects of the present invention] 33 ] The lower arm has a stepped portion positioned on a surface facing radially inward, 32 The capping head described above.

[0064] [Aspects of the present invention] 34 ] manner 17 from 33A spindle assembly comprising: a capping head as described in any one of the above; a lifting shaft extending vertically and to which a pressure block that presses against the top wall of the cap is attached; a spindle that is cylindrical in shape, into which the lifting shaft is inserted and to which the body is attached; and a lifting cylinder that is cylindrical in shape, into which the lifting shaft and the spindle are inserted, wherein the lifting shaft has an upper cam follower that moves the lifting shaft vertically; the spindle has a spindle gear that rotates the spindle around a central axis; and the lifting cylinder has a cylindrical cone cam and a lower cam follower that moves the lifting cylinder vertically.

[0065] [Aspects of the present invention] 35 ] A turret that rotates around a turret axis, and an embodiment that is positioned on the outer circumference of the turret. 34 A capping device comprising: a spindle assembly as described above; a fixed gear that meshes with the spindle gear and extends around the turret axis; an upper cam that extends around the turret axis and engages with the upper cam follower; and a lower cam that extends around the turret axis and engages with the lower cam follower.

[0066] [Aspects of the present invention] 36 ] A configuration comprising a filler for filling a screw-top can with contents, and the supply of the screw-top can discharged from the filler. 35 A capping system comprising the capping device described in [reference], wherein the transport direction of the screw-top can discharged from the filler and heading toward the capping device extends along the tangent to the outer circumference of the turret when viewed from the turret axis direction. [Effects of the Invention]

[0067] The above embodiment of the present invention no KiThe capping head, spindle assembly, capping device, and capping system allow for a simplified body shape, increased body strength, and reduced weight. Furthermore, the capping head's external dimensions can be made more compact, reducing weight and increasing the capping speed, thereby improving production efficiency. [Brief explanation of the drawing]

[0068] [Figure 1] Figure 1 is a perspective view showing the capping head and its body according to this embodiment. [Figure 2] Figure 2 is a perspective view showing the capping head and its body according to this embodiment. [Figure 3] Figure 3 is a cross-sectional view (longitudinal cross-sectional view) showing the capping head and its body according to this embodiment. [Figure 4] Figure 4 is a bottom view of the capping head, showing the assembly jig attached to multiple lower arms. The molding roller is shown as a transparent view with a dashed line. [Figure 5] Figure 5 is an enlarged view of section V in Figure 4. [Figure 6] Figure 6 is an enlarged view of section VI of Figure 4. [Figure 7] Figure 7 is a perspective view showing the body of the capping head according to this embodiment. [Figure 8] Figure 8 is a perspective view showing the body of the capping head according to this embodiment. [Figure 9] Figure 9 is a perspective view showing the body flange of the capping head in this embodiment. [Figure 10] Figure 10 is a cross-sectional view (longitudinal cross-sectional view) of the spindle assembly of this embodiment, with the capping head shown in a simplified form. [Figure 11] Figure 11 is a cross-sectional view (vertical cross-sectional view) showing a part of the capping device of this embodiment, with the capping head shown in a simplified form. [Figure 12]Figure 12 is a schematic side view showing the outer periphery of the capping device of this embodiment unfolded on a plane, illustrating the operation of the spindle assembly and the capping head. [Figure 13] Figure 13 is a schematic top view illustrating the capping system of this embodiment. [Figure 14] Figure 14 is a schematic cross-sectional view (cross-sectional view) of the body of the capping head of the first modified example of this embodiment. [Figure 15] Figure 15 is a schematic cross-sectional view (longitudinal cross-sectional view) showing the body of the capping head of the first modified example of this embodiment. [Figure 16] Figure 16 is a schematic diagram of a screw illustrating a method for measuring screw depth, showing the number of turns of the screw unfolded on a plane. [Figure 17] Figure 17 is a cross-sectional (longitudinal) image showing the vicinity of the lower end of the peripheral wall of the cap after capping, and is a diagram illustrating the evaluation of the hem curl. [Figure 18] Figure 18 is a perspective view showing a portion of the capping head of a second modified example of this embodiment. [Figure 19] Figure 19 is a cross-sectional view (longitudinal section) showing a portion of the capping head in Figure 18. [Modes for carrying out the invention]

[0069] The body 1 of the capping head 10, the capping head 10, the spindle assembly 80, the capping device 120, and the capping system 100 of one embodiment of the present invention will be described with reference to Figures 1 to 13. In this specification, the capping head 10, the spindle assembly 80, etc., may be simply referred to as the device.

[0070] The capping head 10, spindle assembly 80, and capping device 120 of this embodiment are devices for attaching a cap to the mouth of a bottomed cylindrical screw-top can (can) and sealing the screw-top can. Examples of screw-top cans and caps can be used, such as those described in Japanese Patent Application Publication No. 2019-011103. Note that "screw-top can" may be replaced with "bottle can." The cap is, for example, topped cylindrical.

[0071] Detailed illustrations are omitted, but the general configuration of the screw-on can and cap is as follows. Screw-cap cans are made of, for example, aluminum alloy. A screw-cap can comprises a can body, which is the peripheral wall of the can, and a can bottom, which is the bottom wall of the can. The opening of the can body is a nozzle section with a smaller diameter than the rest of the can (body and shoulder). The nozzle section is roughly cylindrical with the can axis at its center. The nozzle section has a curled section, a male threaded section, and a bulging section in that order, extending from its opening end toward the can bottom along the can axis.

[0072] The bulge is annular in shape with the can shaft as the center. The bulge is formed to protrude outward from the male thread portion in the can diameter direction perpendicular to the can shaft. As shown in Figure 17(a), the bulge 201 has a convex shape that bulges outward in the can diameter direction in the cross section (longitudinal section) of the nozzle portion 200 along the can shaft.

[0073] The cap 300 has a cap body that is cylindrical with a top and fits over the nozzle portion 200, and a disc-shaped liner (not shown) positioned on the inner surface of the top wall of the cap body. The liner contacts the curled portion of the nozzle portion 200. The cap body is made of, for example, an aluminum alloy, and the liner is made of, for example, a resin. In this specification, when simply referring to the peripheral wall 301 and the top wall of the cap 300, unless otherwise specified, it refers to the peripheral wall 301 and the top wall of the cap body. As shown in Figure 17(c), etc., the lower end of the peripheral wall 301 of the cap 300 is wrapped around the bulge portion 201.

[0074] As shown in Figures 1 to 3, the capping head 10 comprises a body 1 centered on a central axis O, a pressure block 2, a pivot shaft (support member) 3, a cam follower 4, a molding roller 5, and a biasing member 6. Also, as shown in Figure 12, the central axes (can axes; not shown) of the screw-on can B and cap 300 capped by the capping head 10 are arranged coaxially with the central axis O shown in Figures 1 to 3.

[0075] Here, we will explain the "definition of direction" in this embodiment. In this embodiment, the direction in which the central axis O of the body 1 extends is called the vertical direction. In other words, the central axis O extends in the vertical direction. The vertical direction corresponds to the Z-axis direction in each figure. In the vertical direction, the cam follower 4 and the forming roller 5 are positioned at different locations from each other. Of the vertical directions, the direction from the forming roller 5 toward the cam follower 4 is called the upper side (+Z side), and the direction from the cam follower 4 toward the forming roller 5 is called the lower side (-Z side). The vertical direction can also be referred to as the axial direction. In this case, the upper side corresponds to one side of the axial direction, and the lower side corresponds to the other side of the axial direction.

[0076] The direction perpendicular to the central axis O is called the radial direction. Within the radial direction, the direction approaching the central axis O is called the radially inward direction, and the direction moving away from the central axis O is called the radially outward direction. The direction of rotation around the central axis O is called the circumferential direction. Of the circumferential directions, a predetermined direction of rotation is called the circumferential direction one side C1, and the opposite direction of rotation is called the circumferential direction other side C2. In this embodiment, as shown in Figure 4, in a bottom view of the capping head 10 from below, the clockwise direction around the central axis O is the circumferential direction one side C1, and the counterclockwise direction is the circumferential direction other side C2.

[0077] Furthermore, the shaft central axis A, which is the central axis of the support shaft 31 of the oscillating shaft 3 (described later), is positioned radially outward from the central axis O and extends parallel to the central axis O in the vertical direction (Z-axis direction). In this embodiment, the definition of the direction based on the shaft central axis A of the oscillating shaft 3 is distinguished from the definition of the direction based on the central axis O of the body 1 described above, and is as follows.

[0078] The direction perpendicular to the shaft's central axis A is called the shaft's radial direction. Within the shaft's radial direction, the direction approaching the shaft's central axis A is called the inner shaft radial direction, and the direction moving away from the shaft's central axis A is called the outer shaft radial direction. The direction in which the shaft rotates around its central axis A is called the circumferential direction of the shaft.

[0079] As shown in Figure 10, the capping head 10 is mounted on a spindle assembly 80 that extends vertically and constitutes part of the spindle assembly 80. Specifically, the spindle assembly 80 is positioned above the capping head 10, and the lower end of the spindle assembly 80 is inserted into the capping head 10 from above. More specifically, the lower end of the spindle 85, which will be described later, is attached to the body 1. Also, the lifting shaft 81, which will be described later, is attached to the pressure block 2. The central axis (spindle axis) of the spindle assembly 80 is positioned coaxially with the central axis O of the body 1. The capping head 10 is supported by the spindle assembly 80 and moves vertically together with the spindle assembly 80. The body 1 is rotated about the central axis O by the spindle 85.

[0080] Furthermore, the spindle 85 is fixed to the body 1 while being inserted inside the cylindrical cone cam (cam) 7 of the lifting cylinder 90, which will be described later, within the spindle assembly 80. As shown in Figures 1 to 3, the cone cam 7 is located on the upper side of the body 1 and extends vertically around the spindle axis (central axis O).

[0081] As will be explained in more detail later, in Figures 10 and 11, the lifting shaft 81, spindle 85, capping head 10, and lifting cylinder 90 including the cone cam 7 are connected to separate cam mechanisms 126 and 127, which will be described later, and move in the vertical direction by each of the cam mechanisms 126 and 127. In addition, the spindle 85 and body 1 rotate around the central axis O relative to the cone cam 7. The cone cam 7 may also be one of the components of the capping head 10. In this case, the capping head 10 further includes the cone cam 7.

[0082] As shown in Figures 1 to 3, the body 1 is substantially cylindrical. In this embodiment, at least a portion of the body 1 is made of an aluminum alloy, specifically, for example, duralumin. In this embodiment, the body body 11 and body flange 12, which will be described later, are made of an aluminum alloy. However, the material of the body 1 is not limited to the example of this embodiment. Specifically, at least a portion of the body 1 may be made of an aluminum alloy, engineering plastic, or FRP. In the case of engineering plastic, a preferred example is PEEK (polyetheretherketone). At least a portion of the body 1 is made of a material with a specific gravity lower than, for example, stainless steel.

[0083] Body 1 comprises a body main body 11 and a body flange 12. The body main body 11 may also be referred to as a body base or body base.

[0084] As shown in Figures 7 and 8, the body 11 is cylindrical with a central axis O, and specifically, it is substantially cylindrical. The body 11 has a cylindrical outer wall. Therefore, the body 1 has a cylindrical outer surface 1c. As shown in Figure 9, the body flange 12 is annular. Specifically, the body flange 12 is a roughly circular plate shape with a central axis O at its center. The body flange 12 is fixed to the upper end of the body body 11 by bolts or the like.

[0085] Furthermore, as shown in Figures 1 to 3 and Figures 7 to 9, the body 1 has a peripheral wall portion 11c, a bottom wall portion 11d, a body recess (cone cam housing recess) 13, a cylindrical portion 14, a spindle mounting portion 15, a housing cylinder 16, a support projection 17, a skirt portion 11h, a oscillating shaft housing portion 18 provided with a through hole (biasing member housing hole) 23 and a frame 28, an operating portion 21, and a drain hole 22.

[0086] The peripheral wall portion 11c is substantially cylindrical with respect to the central axis O. The peripheral wall portion 11c constitutes the cylindrical portion of the outer circumferential wall of the body 1, located above the bottom wall portion 11d. The bottom wall portion 11d is roughly annular in shape with the central axis O at its center. The outer periphery of the bottom wall portion 11d is connected to the lower end of the peripheral wall portion 11c.

[0087] As shown in Figure 3, the body recess 13 is a concave shape that is recessed downward from the upper surface 1a of the body 1. The body recess 13 is a bottomed hole centered on the central axis O, and specifically, it is a roughly circular hole. The body recess 13 opens to the upper surface 1a and extends in the vertical direction. The body recess 13 is a recess defined by the inner circumferential surface of the body flange 12, the inner circumferential surface of the peripheral wall portion 11c, and the upper surface of the bottom wall portion 11d.

[0088] In this embodiment, the body recess 13 is positioned vertically, extending from the body flange 12 to the upper portion of the body body 11. The body recess 13 extends in a hole-like manner from the body flange 12 to the body body 11. Specifically, the upper part of the body recess 13 is located inside the body flange 12 (through hole), and the lower part of the body recess 13 is located in a recess 11b that is recessed downward from the upper end surface 11a of the body body 11. That is, the body recess 13 penetrates the body flange 12 vertically and is positioned across the recess 11b of the body body 11.

[0089] The vertical dimension between the upper surface 1a of body 1 and the bottom wall 13a of body recess 13 is greater than the vertical dimension between the lower surface 1b of body 1 and the bottom wall 13a. In other words, the vertical dimension between the upper surface 1a of body 1 and the upper surface of bottom wall portion 11d (i.e., the depth dimension of body recess 13) is greater than the vertical dimension between the upper and lower surfaces of bottom wall portion 11d (i.e., the thickness dimension of bottom wall portion 11d).

[0090] Although not specifically shown in the figures, when the cone cam 7 moves downward relative to the spindle 85 and the body 1 fixed to the spindle 85, the body recess 13 accommodates at least the lower end of the cone cam 7. Specifically, the body recess 13 accommodates at least the large-diameter rolling surface 72 and the tapered rolling surface 73, which will be described later and are located at the lower end of the cone cam 7. Furthermore, a portion of the small-diameter rolling surface 71 of the cone cam 7, which will be described later, may also be located in the body recess 13. The small-diameter rolling surface 71, the large-diameter rolling surface 72, and the tapered rolling surface 73 are the parts of the cone cam 7 that the cam follower 4 contacts.

[0091] In Figure 3, reference numeral 13b indicates the inner circumferential surface 13b of the body recess 13. As shown in Figure 3, the inner diameter dimension d1 of the body recess 13 is larger than the outer diameter dimension d2 of the lower end of the cone cam 7 that contacts the cam follower 4. Specifically, the inner diameter dimension d1 of the body recess 13 is the diameter dimension of the inner circumferential surface 13b of the body recess 13. As shown in Figure 7, the inner circumferential surface 13b of the body recess 13 is a cylindrical surface that rises upward from the radially outer end of the bottom wall 13a of the body recess 13.

[0092] The cylindrical portion 14 protrudes upward from the bottom wall 13a of the body recess 13. The cylindrical portion 14 protrudes upward from the inner circumference of the bottom wall portion 11d. The cylindrical portion 14 is cylindrical in shape with a central axis O. As shown in Figure 3, the upper end surface of the cylindrical portion 14 is located below the upper surface 1a of the body 1, and in this embodiment, it is located below the upper end surface 11a of the body body 11. In other words, the upper end surface of the cylindrical portion 14 is located below the lower surface of the body flange 12.

[0093] When the cone cam 7 moves downward from the raised end position (standby position) shown in Figure 3 to the lower end position (closed position) (not shown), which is the lowest position within its vertical stroke range, the lower end of the cone cam 7 faces the upper end surface of the cylindrical portion 14 with a gap between them. The vertical dimension (insertion depth from the upper surface 1a of the body 1) into which the cone cam 7 in the lower end position is inserted into the body recess 13 is the same as or greater than the vertical dimension L of the body flange 12.

[0094] The outer circumferential surface of the cylindrical portion 14 is positioned radially inward from the inner circumferential surface 13b of the body recess 13 (i.e., the inner circumferential surface of the peripheral wall portion 11c) (see Figure 7). Therefore, a circular ring-shaped groove centered on the central axis O is provided between the outer circumferential surface of the cylindrical portion 14 and the inner circumferential surface 13b of the body recess 13. This groove opens upward and extends in the circumferential direction. When the cone cam 7 moves downward relative to the spindle 85 and the body 1 fixed to the spindle 85, the lower end of the peripheral wall of the cone cam 7 may be positioned in the groove.

[0095] As shown in Figure 3, the spindle mounting portion 15 is located at the bottom of the body recess 13. The spindle mounting portion 15 is located inside the body 11. The spindle mounting portion 15 opens onto the upper end surface of the cylindrical portion 14 and extends vertically. The spindle mounting portion 15 is a substantially circular hole centered on the central axis O. The inner diameter dimension d1 of the body recess 13 is larger than the diameter dimension of the spindle mounting portion 15. The lower end of the spindle 85 is inserted into the spindle mounting portion 15. The spindle mounting portion 15 and the spindle 85 are fastened to each other, for example, by screwing them together. That is, the spindle mounting portion 15 is attached to the spindle 85.

[0096] The upper part of the spindle mounting portion 15 is located inside the cylindrical portion 14. Therefore, when viewed radially, the spindle mounting portion 15 (at least its upper part) is positioned to overlap with the body recess 13. In this embodiment, the lower part of the spindle mounting portion 15 is located below the bottom wall 13a. In other words, the upper part of the spindle mounting portion 15 is located on the inner circumference of the cylindrical portion 14, and the lower part of the spindle mounting portion 15 is located on the inner circumference of the bottom wall portion 11d.

[0097] Here, an example of the dimensions related to the body recess 13 is described in detail below. Each of the dimensions below is assumed to have a tolerance of ±10% (numerical range). In this embodiment, the inner diameter dimension d1 of the body recess 13 is 56 mm. The outer diameter dimension d2 of the lower end of the cone cam 7 is 52.7 mm. The radial clearance (clearance on one side) between the body recess 13 and the lower end of the cone cam 7, i.e., [(d1-d2) / 2], is 1.65 mm.

[0098] Furthermore, the vertical dimension h between the upper surface 1a of body 1 and the bottom wall 13a of body recess 13 (the vertical depth dimension of body recess 13) is 23 mm. The vertical stroke amount between the raised end position (standby position) and the lowered end position (closed position) of the cone cam 7 is 14.3 mm. The vertical dimension between the upper surface 1a of body 1 and the lower end surface of the cone cam 7 at the lowered end position, i.e., the cone cam insertion amount, is 10.39 mm. Therefore, the cone cam insertion amount / cone cam stroke amount is approximately 73%.

[0099] Furthermore, the vertical dimension from the upper end position to the lower end position (lower end of the cone cam 7) where the cam follower 4 makes contact with the cone cam 7 is defined as the molding dimension H, which is 14.56 mm. In other words, in this embodiment, the vertical depth dimension h of the body recess 13 is greater than 0 mm and 1.58 H (mm) or less. Preferably, the depth dimension h is 0.714 H (mm) or less. In this embodiment, the cone cam insertion amount / molding dimension H is approximately 71%.

[0100] Furthermore, the vertical dimension (stroke limit dimension, standby position) between the lower end surface of the cone cam 7, which is set to the raised end position, and the bottom wall 13a of the body recess 13 is 26.91 mm. The vertical dimension (stroke limit dimension, close position) between the lower end surface of the cone cam 7, which is set to the lowered end position, and the bottom wall 13a of the body recess 13 is 12.61 mm.

[0101] The housing cylinder 16 protrudes downward from the lower surface 1b of the body 1. The housing cylinder 16 extends downward from the lower surface of the bottom wall portion 11d. The housing cylinder 16 is substantially cylindrical with a central axis O.

[0102] The support projections 17 protrude downward from the lower surface 1b of the body 1. The support projections 17 extend downward from the outer circumference of the lower surface of the bottom wall portion 11d. The support projections 17 are positioned radially outward of the housing cylinder 16. Multiple support projections 17 are provided in a circumferential direction so as to surround the housing cylinder 16 from the radially outward direction (see Figure 8). The number of support projections 17 is the same as the number of molding rollers 5, and in this embodiment, six are provided. The multiple support projections 17 are arranged with spacing between them in the circumferential direction.

[0103] Each support projection 17 is positioned radially outward from the housing cylinder 16, and adjacent support projections 17 in the circumferential direction are positioned far apart from each other. Therefore, the body 1 has weight-reducing sections between the support projections 17 and the housing cylinder 16, and between adjacent support projections 17 in the circumferential direction. The weight-reducing sections are concave spaces formed by hollowing out a part of the body 1.

[0104] The weight-reducing portions between adjacent support projections 17 in the circumferential direction may be referred to as roller shaft housing pockets 19. The roller shaft housing pockets 19 extend vertically inside the body 1 and open to the lower side of the body 1. Multiple roller shaft housing pockets 19 are provided arranged in the circumferential direction. The number of roller shaft housing pockets 19 is the same as the number of molding rollers 5.

[0105] The skirt portion 11h is cylindrical with respect to the central axis O. The skirt portion 11h is located below the peripheral wall portion 11c. The skirt portion 11h constitutes a cylindrical portion of the outer peripheral wall of the body 1, located below the bottom wall portion 11d. The upper end of the skirt portion 11h is connected to the lower end of the peripheral wall portion 11c and the outer peripheral portion of the bottom wall portion 11d. The outer peripheral surface of the skirt portion 11h and the outer peripheral surface of the peripheral wall portion 11c are continuous in the vertical direction, and each outer peripheral surface is formed integrally without any steps. The outer peripheral surface of the skirt portion 11h and the outer peripheral surface of the peripheral wall portion 11c each constitute a part of the outer peripheral surface 1c of the body 1.

[0106] Support projections 17 are positioned radially inward of the skirt portion 11h. The outer circumference of the lower part of the support projections 17 is connected to the inner circumference of the skirt portion 11h. The skirt portion 11h and the multiple support projections 17 are formed integrally. The skirt portion 11h surrounds the multiple support projections 17, the multiple roller shaft housing pockets 19, the housing cylinder 16, and a part of the pressure block 2 from the radial outside.

[0107] The oscillating shaft housing 18 is positioned between the outer and inner circumference of the body 1. Specifically, the oscillating shaft housing 18 includes a portion positioned between the outer and inner circumference of the body main body 11 and a portion positioned between the outer and inner circumference of the body flange 12. As shown in Figures 3 and 7, the oscillating shaft housing 18 has through holes 23 that penetrate the body main body 11 and the body flange 12 in the vertical direction, and frames 28 positioned adjacent to the through holes 23 in the circumferential direction. The oscillating shaft housing 18 has a plurality of through holes 23 and a plurality of frames 28. The plurality of through holes 23 are positioned at intervals from each other in the circumferential direction. The plurality of frames 28 are positioned at intervals from each other in the circumferential direction. The through holes 23 and frames 28 are positioned alternately in the circumferential direction.

[0108] The through-holes 23 extend vertically through the interior of the body 1. The through-holes 23 penetrate the body 1 in the vertical direction. The number of through-holes 23 is the same as the number of biasing members 6, and multiple through-holes 23 are provided arranged in the circumferential direction. In this embodiment, six through-holes 23 are provided in the body 1 at equal pitches in the circumferential direction. Furthermore, the distance (i.e., radial dimension) between the central axis (shaft central axis A) of each through-hole 23 and the central axis O is the same for all of them. That is, each through-hole 23 is arranged so that the distance from the central axis O is equal for all of them. Each biasing member 6 is housed in each through-hole 23. In addition, the support shafts 31 of each oscillating shaft 3, which will be described later, are inserted through each through-hole 23 and protrude upward and downward from each through-hole 23. That is, the oscillating shafts 3 are inserted through the through-holes 23.

[0109] As shown in Figure 7, the through-hole 23 is positioned around the spindle mounting portion 15 (cylindrical portion 14). The oscillating shaft housing portion 18, in which the through-hole 23 is provided, is positioned radially between the spindle mounting portion 15 and the outer circumferential wall of the body 11. The body 11, spindle mounting portion 15, and oscillating shaft housing portion 18 are connected to each other and, in this embodiment, are integrally formed from a single component. In this embodiment, the body 11, spindle mounting portion 15, and oscillating shaft housing portion 18 may collectively be referred to simply as the body 11.

[0110] The body 11 is a single cylindrical body formed without any joints. That is, the body 11 is integrally formed by hollowing out a single material through machining or other processes. The body 11 is made of aluminum alloy, but it may also be made of engineering plastic or FRP (fiber-reinforced plastic). In the case of engineering plastic, a preferred example is that it may be made of PEEK (polyetheretherketone).

[0111] The peripheral wall portion 11c of the body body 11 includes a cylindrical outer peripheral wall of the body body 11 (annular wall portion on which the outer peripheral surface 1c is formed), a cylindrical inner peripheral wall of the body body 11 (annular wall portion adjacent to the radially outer side of the body recess 13), and a frame 28 that radially connects the outer peripheral wall and the inner peripheral wall.

[0112] The through-hole 23 is a hole (space) defined by the cylindrical outer circumferential wall of the body 11, the cylindrical inner circumferential wall of the body 11, and the frame 28 that radially connects the outer circumferential wall and the inner circumferential wall. Specifically, as shown in Figure 7, the through-hole 23 is formed by being surrounded by the inner wall surface 23g of the outer circumferential wall of the body 11, the outer wall surface 23h of the inner circumferential wall of the body 11, and the circumferentially facing side wall surface 23i of the frame 28. The spindle mounting portion 15 (cylindrical portion 14) is connected to the inner circumferential wall of the body 11 via the bottom wall portion 11d.

[0113] As shown in Figures 3 and 7 to 9, the through hole 23 has a body hole portion 23a located in the body body 11 and a flange hole portion 23b located in the body flange 12. The body hole portion 23a and the flange hole portion 23b overlap each other when viewed from the top and bottom.

[0114] The main body hole 23a extends vertically through the interior of the main body 11 and penetrates the main body 11 in the vertical direction. Specifically, the main body hole 23a penetrates the peripheral wall 11c, the bottom wall 11d, and the support projection 17 in the vertical direction.

[0115] As shown in Figures 3, 7, and 8, the main body hole 23a has a housing hole 23c and a bearing hole 23d. The housing hole 23c is located in the part of the main body hole 23a other than the lower end. The housing hole 23c opens into the upper end surface 11a of the main body 11 and is recessed downward from this upper end surface 11a. The housing hole 23c is a multi-stage hole that extends in the vertical direction, and the inner diameter dimension decreases in stages as it goes downward.

[0116] The housing hole 23c has an opening 23e that opens into the upper end surface 11a of the body 11, and a lower hole 23f located below the opening 23e. In other words, the through hole 23 has an opening 23e and a lower hole 23f.

[0117] The opening 23e has a triangular shape when viewed from above. The circumferential dimension of the opening 23e (opening width dimension) decreases as it moves radially inward. In this embodiment, the maximum value of the circumferential dimension of the opening 23e is greater than the maximum value of the circumferential dimension of the support projection 17. Furthermore, the radially inward end of the opening 23e opens into the inner circumferential surface 13b of the body recess 13. Specifically, the radially inward end of the opening 23e opens along the entire vertical length of the inner circumferential surface 13b. In other words, the inner circumferential surface 13b of the body recess 13 is divided at multiple points in the circumferential direction by each opening 23e that opens into the inner circumferential surface 13b.

[0118] The lower hole 23f is located above the bearing hole 23d. The inner diameter of the lower hole 23f is smaller than the inner diameter of the opening 23e and larger than the inner diameter of the bearing hole 23d. The lower hole 23f is located inside the support projection 17. The inner diameter of the lower hole 23f is smaller than the outer diameter of the support projection 17. Of the lower hole 23f, the portion located radially outward from the shaft central axis A has a roughly rectangular shape that extends in the circumferential direction. Of the lower hole 23f, the portion located radially inward from the shaft central axis A has a semicircular shape that convex radially inward.

[0119] The bearing hole 23d is located at the lower end of the main body hole 23a. The bearing hole 23d is located below the housing hole 23c. The bearing hole 23d and the lower hole 23f pass through the support projection 17 in the vertical direction. The bearing hole 23d is a circular hole that extends in the vertical direction. The inner diameter of the bearing hole 23d is smaller than the inner diameter of the housing hole 23c. A bearing member 24, such as a sliding bearing (dry bearing), is fitted into the bearing hole 23d.

[0120] As shown in Figure 7, the frame 28 is positioned between adjacent through holes 23 in the circumferential direction. Specifically, the frame 28 is positioned between adjacent openings 23e in the circumferential direction. The frame 28 is plate-shaped, extending in a direction perpendicular to the circumferential direction, and extends radially. The frame 28 connects the outer and inner circumferential parts of the body 11. The circumferential dimension (width dimension) of the frame 28 is approximately constant along the radial direction.

[0121] As shown in Figures 3 and 9, the flange hole 23b penetrates the body flange 12 in the vertical direction. The flange hole 23b is a circular hole extending in the vertical direction. The inner diameter of the flange hole 23b is smaller than the inner diameter of the housing hole 23c. In this embodiment, the inner diameter of the flange hole 23b is the same as the inner diameter of the bearing hole 23d. A bearing member 25, such as a sliding bearing, is fitted into the flange hole 23b.

[0122] The body flange 12 also has a locking groove 12a. The locking groove 12a is groove-shaped and recesses radially outward from the inner circumferential surface of the body flange 12. The locking groove 12a extends in the vertical direction and opens to the upper and lower surfaces of the body flange 12.

[0123] As shown in Figures 1, 2, and 9, the operating section 21 is a notched recess that extends radially inward from the outer circumferential surface of the body 1. In this embodiment, the operating section 21 is located on the body flange 12 and opens onto the outer circumferential surface of the body flange 12. Multiple operating sections 21 are provided, spaced apart from each other in the circumferential direction.

[0124] When attaching or detaching the body 1 to the spindle 85, a hook-shaped work tool, such as a hook wrench (not shown), is locked to the operating part 21. With the work tool locked to the operating part 21, the body 1 can be attached to or detached from the spindle 85 by operating the work tool and rotating the body 1 circumferentially relative to the spindle 85.

[0125] As shown in Figure 3, the drain holes 22 penetrate the support projection 17 in the vertical direction. Multiple drain holes 22 are provided, with each of the support projection 17 being located on a separate drain hole 22. The upper end of the drain hole 22 opens onto the upper surface of the support projection 17 and is located radially inward from the skirt portion 11h. Specifically, the upper end of the drain hole 22 opens onto a stepped portion facing upward, located between the bearing hole portion 23d and the lower hole portion 23f. The lower end of the drain hole 22 opens onto the lower surface of the support projection 17. In other words, the drain hole 22 connects the inside of the through hole 23 to the outside of the body 1. Liquids such as water accumulated in the through hole 23 are discharged to the outside of the capping head 10 through the drain holes 22.

[0126] The pressure block 2 is positioned on the underside of the body 1. The pressure block 2 is a roughly bottomed cylindrical shape with a central axis O, extending in the vertical direction. The pressure block 2 is fastened to the lower end of the lifting shaft 81, for example by screwing, and is fixed to the lifting shaft 81. During capping, the bottom wall of the pressure block 2 contacts the top wall of the cap 300 from above, pressing against the top wall (see Figure 12).

[0127] As shown in Figure 3, a portion of the pressure block 2 is housed in the housing cylinder 16 of the body 1. Specifically, the upper portion of the pressure block 2 is inserted into the housing cylinder 16. The vertical position of the upper end surface of the pressure block 2 is approximately the same as the vertical position of the lower surface 1b of the body 1. In other words, because the upper portion of the pressure block 2 is housed in the housing cylinder 16 that protrudes downward from the lower surface 1b, it does not penetrate the portion of the body 1 located above the lower surface 1b (i.e., the portion of the body 1 above the bottom wall portion 11d).

[0128] The pressure block 2 does not necessarily have to be one of the components of the capping head 10. In this case, the pressure block 2 is one of the components of the spindle assembly 80. That is, in this case, the spindle assembly 80 further includes the pressure block 2.

[0129] As shown in Figures 1 to 4, the pivot shaft 3 is attached to the body 1 and supports the cam follower 4 and the forming roller 5. The pivot shaft 3 connects the cam follower 4 and the forming roller 5. The pivot shaft 3 supports the cam follower 4 and the forming roller 5 at both ends in the vertical direction. Specifically, the pivot shaft 3 rotatably supports the cam follower 4 at its upper end and rotatably supports the forming roller 5 at its lower end. The pivot shaft 3 is rotated around the shaft central axis A by the cam follower 4 and the biasing member 6, causing the forming roller 5 to oscillate (move toward and away from) the peripheral wall 301 of the cap 300.

[0130] The intermediate portion of the oscillating shaft 3, located between its vertical ends, is positioned (housed) inside the through hole 23. Multiple oscillating shafts 3 are provided, arranged in a circumferential direction. The number of oscillating shafts 3 is the same as the number of cam followers 4 and the same as the number of forming rollers 5.

[0131] The pivot shaft 3 includes a support shaft 31, an upper arm 32, and a lower arm 33. As shown in Figure 3, the support shaft 31 is substantially cylindrical with respect to the shaft central axis A and extends in the vertical direction. The upper end of the support shaft 31 protrudes above the upper surface 1a of the body 1. The lower end of the support shaft 31 protrudes below the lower surface 1b of the body 1 and also below the support projection 17.

[0132] The support shaft 31 is supported by the body 1 via bearing members 24, 25, such as sliding bearings. Multiple bearing members 24, 25 (a pair in this embodiment) supporting each support shaft 31 are provided spaced apart from each other in the vertical direction. Specifically, the upper portion of the support shaft 31 is supported by the body flange 12 via the upper bearing member 25. The lower portion of the support shaft 31 is supported by the support projection 17 via the lower bearing member 24. In other words, the support shaft 31 is rotatably supported by the body 1 via a pair of bearing members 24, 25 provided in the flange hole 23b and the bearing hole 23d. The intermediate portion of the support shaft 31, located between the upper and lower ends, is positioned in the through hole 23. The support shaft 31 is rotatable within a predetermined range around the shaft central axis A.

[0133] The support shaft 31 has a large-diameter portion 31a. The large-diameter portion 31a has a larger outer diameter than the rest of the support shaft 31. The large-diameter portion 31a has a notched locking recess (not shown) that is recessed inward in the shaft diameter direction from the outer circumferential surface of the large-diameter portion 31a.

[0134] As shown in Figure 2, the upper arm 32 is positioned on the upper side of the body 1 and connects the support shaft 31 and the cam follower 4. The upper arm 32 is fixed to the upper end of the support shaft 31 and extends outward from the support shaft 31 in the radial direction of the shaft. Specifically, the upper arm 32 extends from the support shaft 31 toward one side C1 in the circumferential direction.

[0135] The upper arm 32 surrounds the support shaft 31 around its axis (in the circumferential direction of the shaft) and has an upper clamp portion 32a that is deformable to press against the outer surface of the support shaft 31. The upper clamp portion 32a is a curved wall portion that extends in the circumferential direction of the shaft when viewed from above or below. By screwing the fastening screw 34 into the upper arm 32, the upper clamp portion 32a is deformed to narrow its diameter in the radial direction of the shaft. As a result, the inner surface of the upper clamp portion 32a and the outer surface of the support shaft 31 come into close contact, and the upper arm 32 is fixed to the support shaft 31.

[0136] As shown in Figure 1, the lower arm 33 is positioned on the underside of the body 1 and connects the support shaft 31 and the molding roller 5. The lower arm 33 is fixed to the lower end of the support shaft 31 and extends outward from the support shaft 31 in the radial direction of the shaft. Specifically, the lower arm 33 extends from the support shaft 31 toward one side C1 in the circumferential direction.

[0137] The lower arm 33 has a lower clamp portion 33a that surrounds the support shaft 31 around its axis (in the circumferential direction of the shaft) and is deformable to press against the outer surface of the support shaft 31. The lower clamp portion 33a is a curved wall portion that extends in the circumferential direction of the shaft when viewed from above or below. By screwing the fastening screw 35 into the lower arm 33, the lower clamp portion 33a is deformed to narrow its diameter in the radial direction of the shaft. As a result, the inner surface of the lower clamp portion 33a and the outer surface of the support shaft 31 come into close contact, and the lower arm 33 is fixed to the support shaft 31.

[0138] At least one of the upper clamp portion 32a and the lower clamp portion 33a has a deformation assist groove 36 that is arranged on the circumferential surface of the clamp portion and extends in the vertical direction. As shown in Figures 5 and 6, in this embodiment, at least the lower clamp portion 33a has the deformation assist groove 36. The deformation assist groove 36 is groove-shaped, recessed inward in the shaft diameter direction from the outer circumferential surface (clamp portion circumferential surface) of the lower clamp portion 33a and extending in the vertical direction.

[0139] Multiple deformation assist grooves 36 may be provided on the outer circumferential surface of the lower clamp portion 33a (or upper clamp portion 32a) in the direction of the shaft circumference, or only one may be provided. In this embodiment, one deformation assist groove 36 is provided on the lower clamp portion 33a of the lower arm 33 that supports the screw forming roller 5A, which will be described later. In addition, multiple deformation assist grooves 36 are provided on the lower clamp portion 33a of the lower arm 33 that supports the hem rolling roller 5B, which will be described later, at intervals from each other in the shaft circumferential direction. However, the number of deformation assist grooves 36 provided on each lower clamp portion 33a is not limited to this example in this embodiment.

[0140] The deformation assist groove 36 is, for example, an R groove (round groove), and the cross-sectional shape of the groove is a concave arc. The groove width of the deformation assist groove 36 is, for example, 1.5 mm. The number of deformation assist grooves 36 provided in the lower clamp portion 33a (or upper clamp portion 32a) is, for example, three.

[0141] Furthermore, the lower arm 33 has a stepped portion 37 positioned on the radially inward-facing surface of the lower arm 33. Specifically, the stepped portion 37 is positioned at the end of one side C1 in the circumferential direction of the radially inward-facing surface of the lower arm 33. The depth to which the stepped portion 37 recesses radially outward from the radially inward-facing surface of the lower arm 33 increases as it approaches the other side C2 in the circumferential direction. The stepped portion 37 has a wall surface 37a facing one side C1 in the circumferential direction, and an inclined surface 37b that faces radially inward and extends radially outward as it approaches the other side C2 in the circumferential direction.

[0142] As shown in Figures 2 and 3, the cam follower 4 is positioned on the upper side of the body 1. The cam follower 4 contacts the outer circumferential surface of the cone cam 7 and rolls on the outer circumferential surface of the cone cam 7. Specifically, the cam follower 4 rolls on the large-diameter rolling surface 72, the tapered rolling surface 73, and the small-diameter rolling surface 71 of the outer circumferential surface of the cone cam 7, which will be described later. The cam follower 4 engages with the cone cam (cam) 7.

[0143] Multiple cam followers 4 are provided in a row in the circumferential direction. In this embodiment, six cam followers 4 are provided in the circumferential direction, spaced apart from each other.

[0144] The cam follower 4 has a shaft portion 41 that extends in the vertical direction, and a rolling element 42 that is rotatably supported at the lower end of the shaft portion 41 and pressed against the outer surface of the cone cam 7 by the biasing force of a biasing member 6, which will be described later.

[0145] The shaft portion 41 extends parallel to the central axis A of the shaft and is supported at the end of the upper arm 32 on one side C1 in the circumferential direction. The lower end of the shaft portion 41 faces the upper surface 1a of the body 1 from above, with a gap between them.

[0146] The rolling element 42 is annular in shape with a larger outer diameter than the shaft portion 41 and is arranged coaxially with the central axis of the shaft portion 41. The rolling element 42 is attached to the lower end of the shaft portion 41 via a bearing member, such as a rolling bearing. The rolling element 42 is rotatable around the central axis of the shaft portion 41. The lower surface of the rolling element 42 faces the upper surface 1a of the body 1 with a gap between them.

[0147] As shown in Figures 1, 3, and 4, the molding roller 5 is positioned below the body 1 and radially outward from the pressure block 2. The molding roller 5 is connected to the cam follower 4 via a pivot shaft 3 and moves radially as the cam follower 4 moves radially. That is, the capping head 10 is equipped with a pivoting mechanism that rotates the pivot shaft 3 around its axis (shaft central axis A) to pivot the molding roller 5 radially. In this embodiment, this pivoting mechanism includes a cone cam 7, a cam follower 4 that engages with the cone cam 7, and a biasing member 6 that biases the pivot shaft 3 around its axis.

[0148] The molding rollers 5 are provided in the same number as the cam followers 4, arranged in a line in the circumferential direction. In this embodiment, six molding rollers 5 are provided, spaced apart from each other in the circumferential direction. The six (or more) molding rollers 5 are arranged at equal pitches around the central axis O. In this embodiment, "arranged at equal pitches around the central axis O" means that, as shown in Figure 4, when viewed from the axial direction (bottom), if the central angle formed between the central axes of two adjacent molding rollers 5 in the circumferential direction with the central axis O as the center is defined, the difference between the six central angles is, for example, within 5°, and is substantially equivalent. The roll diameter of the molding roller 5 (specifically, the roller body 52 described later) is, for example, φ26 mm.

[0149] As shown in Figure 1, the molding roller 5 includes a roller shaft 51 extending in the vertical direction, a roller body 52 connected to the roller shaft 51 and pressing against the peripheral wall 301 of the cap 300, and a roller biasing section 53.

[0150] The roller shaft 51 is attached to one end C1 in the circumferential direction of the lower arm 33 via a bearing member such as a sliding bearing (not shown). The roller shaft 51 is rotatable around its central axis (roller central axis) relative to the lower arm 33 and is movable within a predetermined range in the vertical direction.

[0151] The roller body 52 is disc-shaped with a larger outer diameter than the roller shaft 51 and is positioned coaxially with the central axis of the roller shaft 51. The roller body 52 is connected to the lower end of the roller shaft 51. The roller body 52 is integrally formed with the roller shaft 51 from a single component. The roller body 52 is positioned below the bottom wall of the pressure block 2.

[0152] The roller biasing section 53 is an elastic member such as a compression coil spring. The roller biasing section 53 biases the roller shaft 51 and the roller body 52 upward relative to the lower arm 33. The roller shaft 51 and the roller body 52 are movable downward against the biasing force of the roller biasing section 53. The upper part of the roller shaft 51 and the roller biasing part 53 are housed in the roller shaft housing pocket 19 of the body 1.

[0153] As shown in Figure 12, the multiple forming rollers 5 include multiple screw forming rollers (RO rollers) 5A that form a screw thread on the peripheral wall 301 of the cap 300 to screw into the mouth portion 200 of the threaded can B, and at least one hem rolling roller (PP roller) 5B that forms a hem around the lower end of the peripheral wall 301 of the cap 300 onto the mouth portion 200. As shown in Figures 1 to 4, in this embodiment, there are four screw forming rollers 5A and two hem rolling rollers 5B. That is, the number of screw forming rollers 5A is greater than the number of hem rolling rollers 5B. The number of screw forming rollers 5A is twice the number of hem rolling rollers 5B. The screw forming rollers 5A and hem rolling rollers 5B are each supported by multiple support shafts 31. Each roller 5 is supported by the support shafts 31 via a lower arm 33.

[0154] The screw forming roller 5A, although not specifically shown, presses the peripheral wall 301 of the cap 300 radially inward to form a screw portion (female screw portion) that conforms to the shape of the male screw portion of the mouth portion 200. The vertical positions of the roller bodies 52 of adjacent screw forming rollers 5A in the circumferential direction are offset from each other. That is, the vertical positions of adjacent screw forming rollers 5A in the circumferential direction are offset from each other.

[0155] The forming tip load at which the screw forming roller 5A presses against the peripheral wall 301 of the cap 300 is, for example, 110 N or less, more preferably 100 N or less, and even more preferably 90 N or less. In this embodiment, "forming tip load" refers to the load at the contact point (tip) of the outer edge of the roller body 52 that contacts the peripheral wall 301 of the cap.

[0156] The torque at which the screw forming roller 5A presses the peripheral wall 301 of the cap 300 around the axis (shaft central axis) A of the support shaft 31 is, for example, 3.0 N·m or less, and more preferably 2.5 N·m or less.

[0157] The hem-rolling roller 5B presses the lower end of the peripheral wall 301 of the cap 300 radially inward, thereby forming the lower end of this peripheral wall 301 into a shape that conforms to the lower part of the bulge 201 of the mouthpiece portion 200 (see Figure 17(c), etc.). The vertical positions of each roller body 52 of the multiple hem-rolling rollers 5B are the same. That is, the vertical positions of the multiple hem-rolling rollers 5B are identical to each other.

[0158] The molding tip load at which the hem-rolling roller 5B presses against the lower end of the peripheral wall 301 of the cap 300 is, for example, 90 N or less, more preferably 80 N or less, and even more preferably 75 N or less.

[0159] The torque at which the hem-wrapping roller 5B presses the lower end of the peripheral wall 301 of the cap 300 around the axis A of the support shaft 31 is, for example, 2.5 N·m or less, and more preferably 2.0 N·m or less.

[0160] As shown in Figure 4, the multiple hem rollers 5B are positioned so as to be rotationally symmetrical with respect to the central axis O, that is, they are arranged at equal pitches in the circumferential direction. In this embodiment, two hem rollers 5B are positioned so as to be 180° rotationally symmetrical with respect to the central axis O. Therefore, the four screw-forming rollers 5A other than the two hem rollers 5B are arranged at unequal pitches in the circumferential direction.

[0161] As shown in Figure 3, the biasing member 6 is an elastically deformable elastic member. In this embodiment, the biasing member 6 is a torsion coil spring that extends spirally around the axis (around the shaft central axis A) of the support shaft 31 (oscillating shaft 3). The support shaft 31 is inserted inside the biasing member 6. The biasing member 6 surrounds a portion of the support shaft 31 (oscillating shaft 3) in the vertical direction around the axis of the support shaft 31. Specifically, the biasing member 6 surrounds the area near the central part of the support shaft 31 in the vertical direction from the outside in the shaft radial direction around the shaft central axis A.

[0162] The biasing member 6 is positioned in the main body hole 23a of the body body 11, specifically, it is positioned (housed) in the housing hole 23c. The biasing member 6 is positioned across the opening 23e and the lower hole 23f. The inner diameter of the biasing member 6 is smaller than the outer diameter of the large diameter portion 31a of the support shaft 31. Also, the outer diameter of the biasing member 6 is larger than the inner diameter of the flange hole 23b of the body flange 12. Therefore, in the vertical direction, the biasing member 6 is positioned so as to be sandwiched between the upper surface of the large diameter portion 31a and the lower surface of the body flange 12.

[0163] Of the two ends of the biasing member 6 in the vertical direction, the upper end is locked into the locking groove 12a of the body flange 12. The lower end of the biasing member 6 is locked into a locking recess provided in the large diameter portion 31a of the support shaft 31. In other words, the upper end of the biasing member 6 is locked to the body flange 12, and the lower end is locked to the support shaft 31 (oscillating shaft 3).

[0164] The biasing member 6 biases the support shaft 31 in the circumferential direction, thereby biasing the cam follower 4 and the molding roller 5 supported by the oscillating shaft 3 radially inward. In other words, the biasing member 6 biases the cam follower 4 and the molding roller 5 radially inward via the oscillating shaft 3.

[0165] Multiple biasing members 6 are provided in a row in the circumferential direction. The number of biasing members 6 is the same as the number of pivot shafts 3, the same as the number of cam followers 4, and the same as the number of molding rollers 5. In this embodiment, six biasing members 6 are provided in the circumferential direction, spaced apart from each other. Each biasing member 6 is positioned in each through hole 23. Furthermore, the entire biasing member 6 is housed in the through hole 23 without being exposed on the outer circumference of the body 11.

[0166] The cone cam 7 has a small diameter rolling surface 71, a large diameter rolling surface 72, a tapered rolling surface 73, and a relief tapered surface 74.

[0167] The small-diameter rolling surface 71 is the smallest diameter portion of the outer surface of the cone cam 7. The outer diameter dimension (diameter dimension) of the small-diameter rolling surface 71 is constant along the vertical direction. The large-diameter rolling surface 72 is positioned at the lower end of the outer circumferential surface of the cone cam 7. The outer diameter of the large-diameter rolling surface 72 is larger than the outer diameter of the small-diameter rolling surface 71.

[0168] The tapered rolling surface 73 is positioned on the outer circumferential surface of the cone cam 7 between the small-diameter rolling surface 71 and the large-diameter rolling surface 72 in the vertical direction. The tapered rolling surface 73 has a tapered shape that extends radially outward as it is directed downward. That is, the diameter of the tapered rolling surface 73 increases as it is directed downward. The upper end of the tapered rolling surface 73 is smoothly connected to the lower end of the small-diameter rolling surface 71. The lower end of the tapered rolling surface 73 is smoothly connected to the upper end of the large-diameter rolling surface 72.

[0169] The relief tapered surface 74 is located on the outer circumferential surface of the cone cam 7, above the small-diameter rolling surface 71. The relief tapered surface 74 is tapered in a way that extends radially outward as it is directed upward. The lower end of the relief tapered surface 74 is connected to the upper end of the small-diameter rolling surface 71.

[0170] In this embodiment, the amount of radial displacement per unit length along the vertical direction (i.e., the inclination with respect to the central axis O) in at least the lower portion of the relief tapered surface 74 is smaller than the amount of radial displacement per unit length along the vertical direction of the tapered rolling surface 73. In other words, the inclination of the relief tapered surface 74 with respect to the central axis O is smaller (gentler) than the inclination of the tapered rolling surface 73 with respect to the central axis O. As a result, a large vertical length of the relief tapered surface 74 is secured, and even when the cone cam 7 is positioned at its lower end relative to the body 1 (although not specifically shown in the figures), interference between the shaft portion 41 and upper arm 32 of the cam follower 4 and the relief tapered surface 74 is suppressed.

[0171] Next, we will explain how to attach the capping head 10 to the cone cam 7 (assembly method). As shown in Figure 4, in this embodiment, an assembly jig (setting block) 60 is used when attaching the capping head 10 to the cone cam 7. The assembly jig 60 is used by inserting it radially inward into the multiple lower arms 33 with the lower pressure block 2 of the body 1 removed from the lifting shaft 81.

[0172] The assembly jig 60 is columnar in shape with a central axis O at its center. When viewed from above, the assembly jig 60 has a roughly star shape. The assembly jig 60 has a plurality of locking arms 61 that are spaced apart from each other in the circumferential direction. The number of locking arms 61 is the same as the number of forming rollers 5, and in this embodiment there are six.

[0173] When attaching the assembly jig 60 to the capping head 10, first, the assembly jig 60 is placed on the underside of the capping head 10, and each locking arm 61 (not shown in the figure) is positioned between adjacent roller bodies 52 in the circumferential direction. From this position, the assembly jig 60 is moved upward toward the body 1, so that the assembly jig 60 is inserted onto the upper side of the roller body 52.

[0174] Next, using a working tool such as a hex wrench (not shown), the assembly jig 60 is rotated to the other side C2 in the circumferential direction. As a result, the radially outer end of the locking arm 61 slides on the radially inward surface of the lower arm 33 and locks into the stepped portion 37, as shown in Figures 5 and 6. At this time, the lower arm 33 is pushed radially outward by the locking arm 61, causing the pivot shaft 3 to rotate in the circumferential direction of the shaft against the biasing force of the biasing member 6, and the cam follower 4 and the forming roller 5 move radially outward. Furthermore, the locking arm 61 contacts the wall surface 37a of the stepped portion 37 from one side C1 in the circumferential direction, thereby restricting further rotation of the assembly jig 60 toward the other side C2 in the circumferential direction.

[0175] In this state, where multiple cam followers 4 are moved radially outward (open state), the lower end of the cone cam 7 can be inserted radially inward of these cam followers 4.

[0176] As shown in Figure 3, once the cone cam 7 is inserted radially inward of the multiple cam followers 4, the assembly jig 60 is removed from the capping head 10 in the reverse order of the procedure described above. As a result, the biasing force of the biasing member 6 causes the oscillating shaft 3 to rotate in the circumferential direction of the shaft, and the cam followers 4 and forming rollers 5 move radially inward, so that each rolling element 42 of the multiple cam followers 4 comes into contact with the outer circumferential surface of the cone cam 7. After attaching the capping head 10 to the cone cam 7, the pressure block 2 is inserted into the housing cylinder 16 of the body 1, and the pressure block 2 is then attached to the lifting shaft 81.

[0177] Next, the spindle assembly 80 of this embodiment will be described in detail. As shown in Figure 10, the spindle assembly 80 extends in the vertical direction. A capping head 10 is positioned at the lower end of the spindle assembly 80. The spindle assembly 80 of this embodiment comprises the capping head 10, a lifting shaft 81, a spindle 85, and a lifting cylinder 90.

[0178] The lifting shaft 81 extends in the vertical direction. The pressure block 2 is attached to the lower end of the lifting shaft 81 by screws or the like and fixed in place (see Figure 11). The lifting shaft 81 includes a shaft portion 82 extending vertically around a central axis O, an upper cam follower 83 that moves the lifting shaft 81 vertically, and a connecting arm 84 that connects the shaft portion 82 and the upper cam follower 83.

[0179] The spindle 85 is cylindrical in shape, extending vertically around a central axis O. The shaft portion 82 of the lifting shaft 81 is inserted into the spindle 85. The spindle 85 is rotatable around the central axis O relative to the shaft portion 82. The body 1 is attached and fixed to the lower end of the spindle 85 by screws or the like. Therefore, body 1 is made rotatable around the central axis O relative to the pressure block 2.

[0180] The spindle 85 has a spindle gear 86 that rotates the spindle 85 around a central axis O. The spindle gear 86 is an external gear centered on the central axis O. In this embodiment, the spindle gear 86 is positioned at the upper end of the spindle 85.

[0181] The lifting cylinder 90 is cylindrical in shape, extending vertically around a central axis O. The shaft portion 82 of the lifting shaft 81 and the spindle 85 are inserted into the lifting cylinder 90. In this embodiment, the lifting cylinder 90 is positioned below the spindle gear 86. The lifting cylinder 90 is movable vertically relative to the lifting shaft 81 and the spindle 85.

[0182] The lifting cylinder 90 includes a cylindrical cone cam 7 and a lower cam follower 91 that moves the lifting cylinder 90 in the vertical direction. The cone cam 7 is positioned at the lower end of the lifting cylinder 90. The lower cam follower 91 is positioned at the upper end of the lifting cylinder 90.

[0183] Next, the capping device 120 of this embodiment and the capping method using it will be described. As shown in Figure 11, the capping device 120 comprises a device base 125 centered on the turret axis T, a turret 121 that rotates around the turret axis T, a spindle assembly 80 positioned on the outer circumference of the turret 121, a fixed gear 122 that meshes with a spindle gear 86 and extends around the turret axis T, an upper cam 123 that extends around the turret axis T and engages with an upper cam follower 83, and a lower cam 124 that extends around the turret axis T and engages with a lower cam follower 91.

[0184] The turret shaft T is parallel to the central axis O and extends in the vertical direction. The turret 121 is roughly cylindrical with the turret shaft T as its center. In Figure 11, only the upper end of the turret 121 is shown, and the other parts are not shown. The turret 121 is connected to the device base 125 via a bearing member 128 that extends around the turret shaft T. The turret 121 is rotationally driven around the turret shaft T relative to the device base 125 by a drive motor or the like (not shown).

[0185] In this embodiment, the direction in which the turret axis T extends is called the turret axis direction. The turret axis direction corresponds to the vertical direction (Z axis direction). The direction perpendicular to the turret axis T is called the turret radial direction. Within the turret radial direction, the direction approaching the turret axis T is called the inner turret radial direction, and the direction moving away from the turret axis T is called the outer turret radial direction. The direction of rotation around the turret axis T is called the turret circumferential direction. As shown in Figures 12 and 13, in this embodiment, the direction in which the turret 121 rotates within the turret circumferential direction is called the turret rotation direction R, and the rotation direction opposite to this is called the opposite direction to the turret rotation direction R or the anti-turret rotation direction.

[0186] Figure 12 is a schematic side view showing the outer periphery of the capping device 120 unfolded on a plane, illustrating the operation of the spindle assembly 80 and the capping head 10 when attaching (capping) the cap 300 to the mouthpiece 200 of the screw-on can B.

[0187] As shown in Figure 11, the spindle assembly 80 is held on the outer circumference of the turret 121 so as to be movable in the vertical direction. Specifically, a part of the lifting cylinder 90 and a part of the connecting arm 84 of the spindle assembly 80 are engaged with a groove (not shown) located on the outer circumference of the turret 121. The groove of the turret 121 extends in the vertical direction, and the spindle assembly 80, while held in the groove of the turret 121, is slidable in the vertical direction relative to the turret 121.

[0188] Multiple spindle assemblies 80 are provided on the outer circumference of the turret 121, arranged around the turret axis T. The multiple spindle assemblies 80 are arranged at equal pitches around the turret axis T on the outer circumference of the turret 121. The number of spindle assemblies 80 is, for example, 10 or more.

[0189] The fixed gear 122 is an annular plate-shaped external gear centered on the turret axis T. The fixed gear 122 is fixed to the device base 125 and extends in the circumferential direction of the turret. The vertical dimension of the spindle gear 86 is greater than the vertical dimension of the fixed gear 122. Therefore, even when the spindle assembly 80 moves in the vertical direction, the meshing state between the fixed gear 122 and the spindle gear 86 is maintained in good condition.

[0190] The upper cam 123 is an annular groove that extends around the entire circumference of the turret axis T. The upper cam 123 is provided on the outer circumferential surface of the device base 125. In this embodiment, the upper cam 123 is positioned above the fixed gear 122. The upper cam 123 changes its vertical position as it approaches the turret axis T.

[0191] As shown in Figure 12, the upper cam 123 has a head lowering portion 123a, a horizontal portion 123b, and a head raising portion 123c. The head lowering portion 123a, the horizontal portion 123b, and the head raising portion 123c are arranged in this order along the turret rotation direction R. The upper cam 123 has only one set of the head lowering portion 123a, the horizontal portion 123b, and the head raising portion 123c.

[0192] The head lowering section 123a extends downward as it moves in the turret rotation direction R.

[0193] The horizontal section 123b is connected to the end of the head lowering section 123a in the turret rotation direction R and extends in the turret rotation direction R. The vertical position of the horizontal section 123b is constant along the turret rotation direction R.

[0194] The head lifting section 123c is connected to the end of the horizontal section 123b in the turret rotation direction R, and extends upward as it moves toward the turret rotation direction R.

[0195] The upper cam mechanism 126 is comprised of an upper cam 123 and an upper cam follower 83 that engages with the upper cam 123. In other words, the capping device 120 includes the upper cam mechanism 126.

[0196] The lower cam 124 is an annular groove that extends around the entire circumference of the turret axis T. The lower cam 124 is provided on the outer circumferential surface of the device base 125. In this embodiment, the lower cam 124 is positioned below the fixed gear 122. The position of the lower cam 124 changes in the vertical direction as it approaches the turret axis T.

[0197] The lower cam 124 has a front lowering section 124a, a first horizontal section 124b, a lowering section 124c, a molding section 124d, an upward section 124e, a second horizontal section 124f, and a rear upward section 124g. The front lowering section 124a, the first horizontal section 124b, the lowering section 124c, the molding section 124d, the upward section 124e, the second horizontal section 124f, and the rear upward section 124g are arranged in this order along the turret rotation direction R. The lower cam 124 has only one set of the front lowering section 124a, the first horizontal section 124b, the lowering section 124c, the molding section 124d, the upward section 124e, the second horizontal section 124f, and the rear upward section 124g. In other words, the lower cam 124 is provided with only one set of components: a lowering section 124c, a molding section 124d, and an upward section 124e.

[0198] The front lowering section 124a extends downward as it moves in the turret rotation direction R. The position of the front lowering section 124a in the turret circumferential direction is the same as the position of the head lowering section 123a in the turret circumferential direction.

[0199] The first horizontal section 124b connects to the end of the front downward section 124a in the turret rotation direction R and extends in the turret rotation direction R. The vertical position of the first horizontal section 124b is constant along the turret rotation direction R. The circumferential position of the first horizontal section 124b is the same as the circumferential position of the end of the horizontal section 123b that is opposite to the turret rotation direction.

[0200] The lowering section 124c is connected to the end of the first horizontal section 124b in the turret rotation direction R, and extends downward as it moves toward the turret rotation direction R.

[0201] The molding section 124d is connected to the end of the lowering section 124c in the turret rotation direction R and extends in the turret rotation direction R. The vertical position of the molding section 124d is constant along the turret rotation direction R.

[0202] The rising section 124e is connected to the end of the molding section 124d in the turret rotation direction R, and extends upward as it moves toward the turret rotation direction R. The circumferential positions of the lowering section 124c, the molding section 124d, and the raising section 124e are the same as the circumferential positions of the intermediate portion of the horizontal section 123b located between the two ends in the circumferential direction of the turret.

[0203] The second horizontal section 124f connects to the end of the upward section 124e in the turret rotation direction R and extends in the turret rotation direction R. The vertical position of the second horizontal section 124f is constant along the turret rotation direction R. The circumferential position of the second horizontal section 124f is the same as the circumferential position of the horizontal section 123b at the end in the turret rotation direction R.

[0204] The rear lifting section 124g is connected to the end of the second horizontal section 124f in the turret rotation direction R, and extends upward as it moves toward the turret rotation direction R. The position of the rear lifting section 124g in the turret circumferential direction is the same as the position of the head lifting section 123c in the turret circumferential direction.

[0205] The lower cam mechanism 127 is composed of a lower cam 124 and a lower cam follower 91 that engages with the lower cam 124. In other words, the capping device 120 includes the lower cam mechanism 127.

[0206] As the spindle assembly 80 is rotated by the turret 121 in the turret rotation direction R around the turret axis T, the upper cam mechanism 126 moves the lifting shaft 81 and pressure block 2, as well as the spindle 85 and body 1, in the vertical direction. In other words, the upper cam mechanism 126 moves the capping head 10 in the vertical direction. The lower cam mechanism 127 also moves the lifting cylinder 90 and its cone cam 7 in the vertical direction.

[0207] Here, we will explain in detail the process of attaching (capping) the cap 300 to the mouthpiece 200 of the screw-on can B using the capping device 120. First, as shown in Figures 12(a) and (b), the unmolded cap 300 is supplied to the mouth portion 200 of the screw-on can B, which is introduced into the capping device 120, and placed over it.

[0208] The screw-top can B, with its cap 300 placed over the mouthpiece 200, is transported along the outer circumference of the capping device 120 and positioned directly below the capping head 10 of the spindle assembly 80, as shown in Figure 12(c). More specifically, the central axis O of the spindle assembly 80 and the can axis of the screw-top can B are coaxially positioned, and while maintaining this positional relationship, the spindle assembly 80 and the screw-top can B move in the turret rotation direction R from Figure 12(c) to Figure 12(g).

[0209] As shown in Figure 12(d), the upper cam follower 83 of the spindle assembly 80 is guided from the head lowering portion 123a to the horizontal portion 123b of the upper cam 123, causing the lifting shaft 81 and pressure block 2, as well as the spindle 85 and body 1, to move downward (see Figures 10 and 11). Also, the lower cam follower 91 of the spindle assembly 80 is guided from the front lowering portion 124a to the first horizontal portion 124b of the lower cam 124, causing the cone cam 7 of the lifting cylinder 90 to move downward following the body 1. Therefore, from Figure 12(c) to Figure 12(d), the contact between the rolling elements 42 of the cam follower 4 and the large-diameter rolling surface 72 of the cone cam 7 is maintained (see Figure 3).

[0210] In Figure 12(d), the pressure block 2 presses against the top wall of the cap 300 from above, and the thread forming roller 5A and the hem rolling roller 5B face the peripheral wall 301 of the cap 300 from the radially outer side, with a gap between them.

[0211] As shown in Figures 12(e) and (f), the lower cam follower 91 is guided from the lowering portion 124c of the lower cam 124 to the forming portion 124d, causing the cone cam 7 of the lifting cylinder 90 to move downward relative to the body 1. Due to this movement and the biasing force of the biasing member 6, the position in which the rolling elements 42 of the cam follower 4 contact the cone cam 7 changes from the large-diameter rolling surface 72 to the tapered rolling surface 73, and further from the tapered rolling surface 73 to the small-diameter rolling surface 71.

[0212] As a result, each cam follower 4 moves radially inward, and each forming roller 5, which is connected to each cam follower 4 via each pivot shaft 3, is also moved radially inward. Furthermore, with the fixed gear 122 and the spindle gear 86 meshed, the spindle assembly 80 is moved in the turret rotation direction R, causing the spindle 85 and body 1 to rotate around the central axis O.

[0213] Therefore, each roller 5 of the screw-forming roller 5A and the hem-wrapping roller 5B contacts the peripheral wall 301 of the cap 300 and rolls on the peripheral wall 301 around the central axis O (can axis). As a result, the screw-forming roller 5A forms a screw portion (female screw portion) on the peripheral wall 301 of the cap 300 that screws into the male screw portion of the mouthpiece portion 200. The hem-wrapping roller 5B forms a hem around the lower end of the peripheral wall 301 of the cap 300, below the bulge portion 201 of the mouthpiece portion 200.

[0214] Next, the lower cam follower 91 is guided from the molded portion 124d of the lower cam 124 to the rising portion 124e, causing the cone cam 7 of the lifting cylinder 90 to move upward relative to the body 1. Due to this movement and the biasing force of the biasing member 6, the position where the rolling elements 42 of the cam follower 4 contact the cone cam 7 changes from the small-diameter rolling surface 71 to the tapered rolling surface 73, and then from the tapered rolling surface 73 to the large-diameter rolling surface 72.

[0215] As a result, each cam follower 4 moves radially outward, and each forming roller 5 connected to each cam follower 4 via each pivot shaft 3 is also moved radially outward. Therefore, each roller 5 of the screw forming roller 5A and the hem rolling roller 5B moves radially outward from the peripheral wall 301 of the cap 300.

[0216] As shown in Figure 12(g), the upper cam follower 83 is guided from the horizontal section 123b of the upper cam 123 to the head rise section 123c, causing the lifting shaft 81 and pressure block 2, as well as the spindle 85 and body 1, to move upward (see Figures 10 and 11). This causes the pressure block 2 to move upward away from the top wall of the cap 300. Additionally, the lower cam follower 91 is guided from the second horizontal section 124f of the lower cam 124 to the rear rise section 124g, causing the cone cam 7 of the lifting cylinder 90 to move upward following the body 1.

[0217] In this way, the cap 300 is capped onto the mouth portion 200 of the screw-on can B, and the screw-on can B is sealed. In this embodiment, the series of actions in which each roller 5 of the screw-forming roller 5A and the hem-rolling roller 5B contacts the peripheral wall 301 of the cap 300, rolls on the peripheral wall 301, and then separates from the peripheral wall 301 is considered as one operation. In other words, the capping device 120 performs capping by a single action.

[0218] In this embodiment, during a series of actions (single action) in which each roller 5 contacts the peripheral wall 301 of the cap 300, rolls on the peripheral wall 301, and then separates from the peripheral wall 301, each roller 5 (screw forming roller 5A and hem rolling roller 5B) makes two rotations on the cap peripheral wall 301 around the cap's central axis (can axis).

[0219] As described above, the capping head 10 comprises a pressure block 2, a thread forming roller 5A, and a hem roller 5B, and the spindle assembly 80 includes this capping head 10. Therefore, in this embodiment, it may be said that the spindle assembly 80 comprises a pressure block 2, a thread forming roller 5A, and a hem roller 5B.

[0220] More specifically, the spindle assembly 80 includes a pressure block 2 positioned on the capping head 10 that presses against the top wall of the cap 300 as the upper cam follower 83 moves downward; a plurality of thread forming rollers 5A provided on the capping head 10 that contact the peripheral wall 301 of the cap 300 as the lower cam follower 91 moves downward and form a threaded portion on the peripheral wall 301 that screws into the mouth portion 200; and at least one hem-rolling roller 5B provided on the capping head 10 that contacts the peripheral wall 301 of the cap 300 as the lower cam follower 91 moves downward and forms a hem around the lower end of the peripheral wall 301 on the mouth portion 200.

[0221] Next, the capping system 100 of this embodiment will be described. As shown in Figure 13, the capping system 100 includes a filler (filling machine) 110 that fills screw-top cans B with contents such as beverages, and a capping device 120 to which the screw-top cans B discharged from the filler 110 are supplied.

[0222] The reference numeral 130 in Figure 13 represents the layout of a conventional capping device 130. Conventionally, the transport direction E of the screw-top cans B discharged from the filler 110 and heading toward the capping device 130 is curved when viewed from above. In contrast, in this embodiment, the transport direction D of the screw-top can B discharged from the filler 110 and heading toward the capping device 120 extends along the tangent to the outer circumference of the turret 121 when viewed from the turret axis direction (i.e., from above).

[0223] In the present embodiment described above, the body main body 11 has a cylindrical outer peripheral wall (outer peripheral surface 1c), that is, the body main body 11 has a cylindrical shape, and the outer shape of the body 1 is simply configured. Further, a through hole 23 is provided in the body 1 so as to penetrate the body 1 in the vertical direction, and a swing shaft 3 for swinging the forming roller 5 is inserted through the through hole 23. Further, the swing shaft housing portion 18 where the through hole 23 is provided is disposed around the spindle mounting portion 15. Since the body 1 of the capping head 10 of the present embodiment has a simple configuration including a cylindrical body main body 11, a spindle mounting portion 15 attached to the spindle 85, and a swing shaft housing portion 18 where the through hole 23 is disposed, the shape of the body 1 is suppressed from becoming complicated while simplifying the structure of the body 1, and its rigidity is enhanced. In particular, when the body main body 11, the spindle mounting portion 15, and the swing shaft housing portion 18 are connected to each other as in the present embodiment, the above-described operational effects are further enhanced. It is more preferable that the body main body 11, the spindle mounting portion 15, and the swing shaft housing portion 18 are integrally formed by a single member.

[0224] Further, cam followers 4 and forming rollers 5 are connected to both upper and lower ends of the swing shaft 3 in the vertical direction, and in the through hole 23 of the body 1, an intermediate portion located between both upper and lower ends of the swing shaft 3 and a biasing member 6 externally inserted into this intermediate portion are housed. The biasing member 6 is provided so as to surround a part (intermediate portion) of the swing shaft 3 around its axis and is housed in the through hole 23.

[0225] According to the present embodiment, since a part (intermediate portion) of the swing shaft 3 and the biasing member 6 (hereinafter referred to as the biasing member 6 etc.) are housed inside the body 1, notches and the like provided for disposing the biasing member etc. in a state of being exposed on the outer peripheral portion of the body as in the prior art are unnecessary. For this reason, in the present embodiment, it is possible to configure the body 1 in a simple shape, and manufacturing is easy. Further, by simplifying the shape of the body 1, the strength of the body 1 can be enhanced.

[0226] Furthermore, by accommodating the biasing member 6 and the like inside the body 1, it is possible to prevent contents such as beverages (particularly sugars that are likely to solidify) scattered from the outside of the body 1 from adhering to the biasing member 6 and the like. For this reason, the performance (function) of the biasing member 6 and the like can be maintained well over a long period, and the maintainability is also good.

[0227] In addition, by enhancing the rigidity of the body 1, the body 1 can be made of a material with a smaller specific gravity compared to stainless steel and the like that conventionally constituted the body, such as aluminum alloys like duralumin, engineering plastics, and resin materials (including composite resin materials) such as FRP (fiber reinforced plastic). Therefore, it is easy to reduce the weight of the capping head 10. In the case of the integrated body main body 11 in which the spindle mounting portion 15 and the swing shaft housing portion 18 are integrally provided on the body main body 11 as in the present embodiment, it is easy to further reduce the weight of the body main body 11 by means of lightening such as hollowing while ensuring the rigidity of the body main body 11.

[0228] [[ID=۸]]

[0229]

[0229] In addition, in the present embodiment, the entire biasing member 6 is accommodated in the through hole 23 without being exposed to the outer peripheral portion of the body main body 11. In this case, the above-described operational effects obtained by accommodating the biasing member 6 in the through hole 23 become more prominent.

[0230] In addition, in the present embodiment, a plurality of through holes 23 are provided at intervals in the circumferential direction, each through hole 23 has an opening portion 23e that opens to the upper end surface 11a of the body main body 11, and the dimension along the circumferential direction of the opening portion 23e becomes smaller as it goes toward the inner side in the radial direction. Further, the opening portion 23e has a triangular hole shape when viewed from above.

[0231] In this case, the circumferential dimensions (i.e., wall thickness) of the portion of the pivot shaft housing 18 located between adjacent through holes 23 in the circumferential direction (frame 28) become less prone to variation at each position in the radial direction, and the strength of the frame 28 is stably increased. Therefore, the strength of the body 1 can be ensured while keeping the spacing between the circumferentially aligned through holes 23 small. Further miniaturization and weight reduction of the capping head 10 can be achieved.

[0232] In this embodiment, the body 1 has a body recess 13 that is recessed downward from the upper surface 1a of the body 1 and accommodates at least the lower end of the cone cam 7. Also, the radial inner end of the opening 23e opens into the inner circumferential surface 13b of the body recess 13. In this case, at least the lower end of the cone cam 7 is inserted into the body recess 13 that opens on the upper surface 1a of the body 1, allowing the cone cam 7 and the body 1 to be positioned closer together in the vertical direction. This reduces the vertical dimensions of the body 1, making it more compact and lighter. Furthermore, the opening 23e of the through hole 23 extends to the inner circumferential surface 13b of the body recess 13, resulting in a large opening 23e. Therefore, this opening 23e also contributes to further weight reduction of the body 1.

[0233] In this embodiment, the through hole 23 has a main body hole portion 23a that penetrates the main body 11 in the vertical direction and a flange hole portion 23b that penetrates the body flange 12 in the vertical direction, and the biasing member 6 is positioned in the main body hole portion 23a. In this case, by placing the biasing member 6 in the main body hole 23a and fixing the body flange 12 to the upper end of the body 11, the biasing member 6 can be easily housed inside the body 1. This facilitates the manufacturing of the capping head 10.

[0234] In this embodiment, the support shaft 31 (oscillating shaft 3) is rotatably supported by the body 1 via a pair of bearing members 24 and 25 provided in the flange hole 23b and the bearing hole 23d. In this case, the support shaft 31 (oscillating shaft 3) is stably supported by a pair of bearing members 24 and 25, which are provided in the flange hole 23b located at the upper end of the body 1 and the bearing hole 23d located at the lower end of the body 1, and are spaced apart in the vertical direction.

[0235] In this embodiment, the biasing member 6 is a torsion coil spring that extends spirally around the axis of the support shaft 31 (oscillating shaft 3), with the upper end of the biasing member 6 locked to the body flange 12 and the lower end locked to the support shaft 31. With the above configuration, the biasing member 6 can be easily assembled inside the body 1 while applying the desired biasing force by locking the upper end of the biasing member 6 to the body flange 12 and the lower end of the biasing member 6 to the support shaft 31 (oscillating shaft 3).

[0236] In this embodiment, the number of through holes 23 is the same as the number of biasing members 6, and multiple holes are provided arranged in the circumferential direction. In this case, each biasing member 6 can be accommodated in each through-hole 23. That is, one biasing member 6 can be placed in each through-hole 23. Therefore, the through-holes 23 can be constructed simply, making the manufacturing of the body 1 easier and increasing its rigidity.

[0237] Furthermore, at least a portion of body 1 is made of one of the following: aluminum alloy, engineering plastic, or FRP. In the case of engineering plastic, a preferred example is PEEK (polyetheretherketone). In this case, while ensuring the rigidity of body 1, it is possible to reduce the weight of body 1 compared to conventional bodies made of stainless steel, etc.

[0238] Specifically, in this embodiment, it was found that the following processing performance could be obtained as a result of making the capping head 10 more compact and lighter. Although not specifically illustrated, for example, in a spindle assembly equipped with a conventional 4-roll type (4 forming rollers) capping head, a capping device equipped with 10 such spindle assemblies, and a capping system equipped with such a capping device, the maximum capping speed for screw-top cans was 300 cpm. "cpm" is a unit representing the number of cans processed (capped cans) per minute. In contrast, in the spindle assembly 80 equipped with a 6-roll type (6 molding rollers 5) capping head 10 of this embodiment, a capping device 120 equipped with 10 of the spindle assemblies 80, and a capping system 100 equipped with the capping device 120, the capping processing speed of screw-on cans B was increased to a maximum of 600 cpm.

[0239] Furthermore, in the capping head 10 of this embodiment, the rolling elements 42 of the cam follower 4 are rotatably supported at the lower end of the shaft portion 41. Therefore, compared to conventional capping heads, the rolling elements 42 can be positioned closer to the upper surface 1a of the body 1. If this configuration were applied to a conventional capping head, there would be a risk of the lower end of the cone cam coming into contact with the upper surface of the body. However, in this embodiment, the body 1 is provided with a body recess 13. That is, at least the lower end of the cone cam 7 can be accommodated in the body recess 13, so that the cone cam 7 and the body 1 can be positioned closer together in the vertical direction, while preventing contact (interference) between these components.

[0240] Therefore, the pressure block 2 and molding roller 5 that form the cap 300 and the cone cam 7 can be positioned closer together in the vertical direction, thereby reducing the vertical dimensions of the body 1. Therefore, according to the capping head 10, spindle assembly 80, and capping device 120 of this embodiment, the external dimensions of the capping head 10 can be made compact and lightweight, increasing the capping processing speed and improving production efficiency.

[0241] In this embodiment, the inner diameter dimension d1 of the body recess 13 is larger than the outer diameter dimension d2 of the lower end portion of the cone cam 7 where the cam follower 4 contacts. With the above configuration, the lower end portion of the cone cam 7 can be reliably inserted into the body recess 13.

[0242] In this embodiment, the spindle mounting portion 15 is disposed at the bottom of the body recess 13 having a bottomed hole shape. In this case, by providing the body recess 13, while making the body 1 more compact and lighter, the spindle 85 can be stably mounted to the spindle mounting portion 15 provided at the bottom of the body recess 13.

[0243] In this embodiment, the inner diameter dimension d1 of the body recess 13 is larger than the diameter dimension of the spindle mounting portion 15. In this case, a gap can be provided in the radial direction between the inner peripheral surface 13b of the body recess 13 and the spindle mounting portion 15. For example, if a part of the lower end portion of the cone cam 7, which is set as the descending end position, is accommodated in this gap, further compactification of the body 1 can be achieved.

[0244] In this embodiment, with the vertical dimension from the upper end position to the lower end position of the cone cam 7 where the cam follower 4 contacts being defined as the forming dimension H, the vertical depth dimension h of the body recess 13 is 1.58H or less. If the vertical depth dimension h of the body recess 13 is set such that h ≦ 1.58H, the above-described operational effects can be obtained by forming the body recess 13, and the rigidity of the body 1 can be sufficiently ensured. [[ID=**21**]] [[ID=**22**]]

[0245] [[ID=**23**]] [[ID=**24**]] [[ID=**25**]]In this embodiment, the body recess 13 is formed as a hole extending in the vertical direction from the body flange 12 to the body main body 11, and the vertical dimension in which the cone cam 7 set as the descending end position is inserted into the body recess 13 is the same as or greater than the vertical dimension L of the body flange 12.In this case, the vertical dimension (cone cam insertion amount) to which the cone cam 7, positioned at its lowered end, enters the body recess 13 is equal to or greater than the vertical dimension L of the body flange 12. Since sufficient insertion space for the cone cam 7 into the body recess 13 is ensured, the body 1 can be made more compact and lighter accordingly.

[0246] In this embodiment, six molding rollers 5 are provided, and the number of screw molding rollers 5A is greater than the number of hem-wrapping rollers 5B. As shown in the above configuration, a larger number of screw forming rollers 5A allows for a smaller forming load (pressing force) per screw forming roller 5A. Therefore, even when the screwed can B is made thinner, deformation of the mouth portion 200 associated with the screw forming process can be suppressed more stably.

[0247] In this embodiment, the capping head 10 is provided with four screw forming rollers 5A and two hem-wrapping rollers 5B. This makes it possible to stably improve the accuracy of the capping process.

[0248] In this embodiment, the vertical positions of adjacent screw-forming rollers 5A (and their roller bodies 52) in the circumferential direction are offset from each other. In this case, the molding locations on the circumferential wall 301 of the cap 300 for adjacent screw molding rollers 5A in the circumferential direction are shifted vertically, thereby suppressing defects such as excessive screw molding at the same location on the cap circumferential wall 301 (especially near the upper groove, which is the starting position of the screw). This suppresses variations in the amount of screw molding at each position in the vertical direction, and equalizes the amount of screw molding in the vertical direction.

[0249] Furthermore, since adjacent screw forming rollers 5A are offset vertically, it becomes possible to position these screw forming rollers 5A closer together without interfering with each other. This makes it possible to keep the outer diameter of the capping head 10 smaller, enabling further compactness and weight reduction.

[0250] In this embodiment, the spindle mounting portion 15 of the body 1 overlaps with the body recess 13 when viewed from the radial direction. As shown in the above configuration, the spindle mounting portion 15 and the body recess 13 are arranged to overlap when viewed from the radial direction, which makes it possible to further reduce the vertical dimension of the body 1.

[0251] In this embodiment, the body 1 has a biasing member housing hole (through hole) 23 that extends in the vertical direction, and the biasing member 6 is placed in the biasing member housing hole 23. In this case, the biasing member 6 is housed in a biasing member housing hole 23, which is provided by hollowing out the body 1 in the vertical direction. This allows the biasing member 6 to be covered from its periphery while maintaining high rigidity of the body 1. Furthermore, compared to the case where a pocket 11e and a separate cover 8 covering the pocket 11e are provided in the body 1, as in the second modified example of this embodiment described later, the machining process for cutting the biasing member housing hole 23 into the body 1 is not complex, thus simplifying the manufacturing of the body 1. Moreover, with an integrated body body 11 as in this embodiment, it is easy to further reduce the weight of the body body 11 by removing material while maintaining the rigidity of the body body 11.

[0252] Furthermore, in this embodiment, the skirt portion 11h prevents the multiple support projections 17, multiple roller shaft housing pockets 19, housing cylinder 16, and part of the pressure block 2 from being exposed to the outside of the device. This enhances the aesthetic appearance of the device.

[0253] Furthermore, the skirt portion 11h and the multiple support projections 17 are connected to each other. This increases the rigidity of each support projection 17, and each support shaft 31, which is supported by each support projection 17 via the bearing member 24, rotates accurately around the shaft central axis A. As a result, the cap peripheral wall 301 can be molded with higher precision by each molding roller 5 connected to each support shaft 31.

[0254] In this embodiment, a portion of the pressure block 2 is housed in a housing cylinder 16 that protrudes downward from the lower surface 1b of the body 1. In this case, by housing a portion of the pressure block 2 in the housing cylinder 16, it becomes unnecessary to provide a housing space (insertion space) for the pressure block 2 inside the body 1, making it possible to further reduce the vertical dimension between the lower surface 1b of the body 1 and the body recess 13. As a result, the body 1 can be made even more compact and lighter.

[0255] In this embodiment, the body 1 has weight-reducing sections between the support projection 17 and the housing cylinder 16, and between adjacent support projections 17 in the circumferential direction. Therefore, further weight reduction of body 1 can be achieved.

[0256] In this embodiment, a deformation assist groove 36 is provided in at least one of the upper clamp portion 32a and the lower clamp portion 33a of the pivot shaft 3. In this case, a deformation assist groove 36 extending in the vertical direction is provided on the circumferential surface (circumferential surface of the clamp) of the upper clamp portion 32a or the lower clamp portion 33a (hereinafter sometimes simply referred to as the clamp portion), making it easier for the clamp portion to deform in a direction that presses against the outer circumferential surface of the support shaft 31 (inward in the shaft diameter direction). This makes it possible to keep the outer diameter dimension (diameter dimension) of the support shaft 31 small (i.e., make the support shaft 31 thinner), and accordingly, the outer diameter dimension of the capping head 10 as a whole can also be kept small, making further weight reduction possible.

[0257] In this embodiment, a stepped portion 37 is formed on the radially inward-facing surface of the lower arm 33. In this case, by using the assembly jig 60 to move the cam follower 4 and the forming roller 5 radially outward against the biasing force of the biasing member 6 (open state), the locking arm 61 can be locked to the stepped portion 37 of the lower arm 33, thereby stably maintaining the open state. The cone cam 7 can be stably inserted radially inward of the multiple cam followers 4 arranged in the circumferential direction, making the assembly work of the capping head 10 and the cone cam 7 easier.

[0258] Furthermore, in the capping system 100 of this embodiment, the transport direction D of the screw-top can B discharged from the filler 110 and heading toward the capping device 120 extends along the tangent to the outer circumference of the turret 121 when viewed from the direction of the turret axis T. According to the capping system 100 of this embodiment, the screw-top cans B discharged from the filler 110 are smoothly supplied to the capping device 120 without their direction of transport being abruptly changed, that is, they are less affected by centrifugal force. As a result, the capping processing speed can be stably increased, and production efficiency can be further improved.

[0259] Here, other problems of this embodiment and their solutions will be described.

[0260] In the capping device described in Japanese Patent Publication No. 2003-146392 (hereinafter referred to as "Known Document 1"), the cone cam is guided down by the first-stage lowering section of the guide bar for the lower cam, causing the RO roller (screw forming roller) and PP roller (hem rolling roller) to press against the circumferential wall of the cap. Subsequently, the cone cam is guided up by the upper section of the guide bar, thereby temporarily releasing the contact between the RO roller and PP roller and the cap. After that, the cone cam is guided down again by the second-stage lowering section of the guide bar, causing the RO roller and PP roller to press against the circumferential wall of the cap again.

[0261] More specifically, in the capping device described in Known Document 1, the capping method involves a first capping step in which the RO roller and PP roller capp each other once to form the threaded portion and the temper evidence portion (hem portion), followed by a second capping step in which the cap is capped again in the same manner as the first capping step. In other words, Known Document 1 employs a double-action capping method in which the RO roller and PP roller make contact with the peripheral wall of the cap, roll along the peripheral wall, and then separate from the peripheral wall, a series of actions performed twice. Conventionally, the formability of the threaded portion and the tempered evidence portion is ensured by a double-action mechanism.

[0262] In this type of screw-top can, thinning (lightening) is required to reduce costs and other factors. However, as shown in Figure 10 of well-known document 1, when four RO rollers are arranged at equal pitches in the circumferential direction and two PP rollers are arranged at equal pitches in the circumferential direction, the thinned-walled nozzle section is prone to deformation into an elliptical shape or the like in a cross-sectional view perpendicular to the can axis due to the lateral load during capping.

[0263] Furthermore, this type of capping device requires compactness and increased capping speed to improve production efficiency, while ensuring good accuracy in screw forming and temper evidence part forming (hem forming).

[0264] Another objective of this embodiment is to provide a capping device and capping system that can suppress deformation of the nozzle portion during capping, thereby enabling thinner walls, ensuring good molding accuracy of the caps, and also enabling the device to be made more compact and the capping processing speed to improve production efficiency.

[0265] According to the capping device 120 of this embodiment, a total of six rollers 5, including four thread-forming rollers 5A and two hem-wrapping rollers 5B, are arranged at equal pitches around the central axis O on the capping head 10 of the spindle assembly 80. During capping, the mouth portion 200 of the threaded can B is pressed evenly by the six rollers 5 in the circumferential direction around the central axis O (can axis), thereby suppressing deformation of the mouth portion 200 into an elliptical shape or the like in cross-sectional view.

[0266] This makes it possible to thin the wall of the screw-on can B (especially the neck portion 200), and also to thin the cap peripheral wall 301 in accordance with the wall thickness of the neck portion 200. As a result, the screw-on can B can be made lighter and its cost reduced. Furthermore, even if the operation of each roller 5 in forming the cap 300 is limited to one time (single action), good forming amounts (processing accuracy) for both screw forming and hem forming can be ensured.

[0267] By making the capping a single-action mechanism, the circumference (total length) of the lower cam 124 extending around the turret axis T can be kept short, allowing the diameter of the turret 121 (turret diameter) to be kept small and enabling a more compact device. Alternatively, compared to conventional double-action type capping devices, the single-action type capping device 120 of this embodiment can significantly increase the rotational speed of the turret 121 around the turret axis T, provided that the turret diameter is the same.

[0268] As described above, according to this embodiment, deformation of the nozzle portion 200 during capping can be suppressed, enabling thinner walls, ensuring good molding accuracy of the cap 300, and allowing for a more compact device and increased capping processing speed to improve production efficiency.

[0269] In this embodiment, the forming tip load at which the screw forming roller 5A presses against the peripheral wall 301 of the cap 300 is 110 N or less, and the forming tip load at which the hem rolling roller 5B presses against the lower end of the peripheral wall 301 of the cap 300 is 90 N or less. As described above, the forming tip load of the screw forming roller 5A is set to 110N or less, and the forming tip load of the hem-wrapping roller 5B is set to 90N or less, so that the lateral load (load from the radial direction perpendicular to the can axis) acting on the mouth portion 200 during capping is kept sufficiently small. Even with a thinned mouth portion 200, deformation during capping is stably suppressed. Furthermore, despite the small forming tip load of each roller 5, in this embodiment, single action can be used to obtain capping performance (screw depth dimension, hem-wrapping dimension, etc.) equivalent to that of a conventional double-action type capping device.

[0270] Furthermore, in order to stably obtain the above-mentioned effects, the molding tip load at which the screw forming roller 5A presses against the peripheral wall 301 of the cap 300 is more preferably 100N or less, and more preferably 90N or less. Also, the molding tip load at which the hem rolling roller 5B presses against the lower end of the peripheral wall 301 of the cap 300 is more preferably 80N or less, and more preferably 75N or less.

[0271] In this embodiment, the torque at which the screw forming roller 5A presses the peripheral wall 301 of the cap 300 around the axis A of the support shaft 31 is 3.0 N·m or less, and the torque at which the hem rolling roller 5B presses the lower end of the peripheral wall 301 of the cap 300 around the axis A of the support shaft 31 is 2.5 N·m or less. As described above, the torque around the support shaft 31 of the screw forming roller 5A is set to 3.0 N·m or less, and the torque around the support shaft 31 of the hem-wrapping roller 5B is set to 2.5 N·m or less, thereby sufficiently reducing the lateral load acting on the jaw portion 200 during capping. Even with a thinned jaw portion 200, deformation during capping is stably suppressed. Furthermore, despite the small torque of each roller 5, this embodiment allows for capping performance (screw depth dimension, hem-wrapping dimension, etc.) equivalent to that of a conventional double-action type capping device, using single action.

[0272] Furthermore, in order to stably obtain the above-mentioned effects, the torque at which the screw forming roller 5A presses the peripheral wall 301 of the cap 300 around axis A of the support shaft 31 is more preferably 2.5 N·m or less. Also, the torque at which the hem rolling roller 5B presses the lower end of the peripheral wall 301 of the cap 300 around axis A of the support shaft 31 is more preferably 2.0 N·m or less.

[0273] In this embodiment, the lower cam 124 is provided with only one set of the lowering portion 124c, the molding portion 124d, and the raising portion 124e. In this case, the lower cam follower 91 is guided downward by the lowering portion 124c of the lower cam 124, and as a result, the thread forming roller 5A and the hem rolling roller 5B come into contact with the peripheral wall 301 of the cap 300. Also, while the lower cam follower 91 is guided by the forming portion 124d of the lower cam 124, the thread forming roller 5A forms the threads on the peripheral wall 301 of the cap 300, and the hem rolling roller 5B forms the hem on the lower end of the peripheral wall 301 of the cap 300. Furthermore, the lower cam follower 91 is guided upward by the rising portion 124e of the lower cam 124, and as a result, the thread forming roller 5A and the hem rolling roller 5B move away from the peripheral wall 301 of the cap 300. Through the action of each roller 5, the peripheral wall 301 of the cap 300 is well formed.

[0274] In this embodiment, four screw forming rollers 5A are provided on the capping head 10. In this case, since a large number of screw forming rollers 5A are available, even if the operation of each screw forming roller 5A forming the screw portion on the cap 300 is limited to one time (single action), good accuracy in screw forming can be maintained.

[0275] The present invention is not limited to the embodiments described above, and modifications to the configuration, etc., are possible without departing from the spirit of the invention, as described below. In the illustrations of modified examples, the same reference numerals are used for the same components as in the embodiments described above, and the main differences will be described below.

[0276] Figures 14 and 15 are schematic cross-sectional views illustrating a first modified example of the body 1 of the capping head 10 described in the above-described embodiment. Specifically, Figure 14 shows a cross-sectional view of the body 1 perpendicular to the central axis O, and Figure 15 shows a longitudinal cross-sectional view of the body 1 along the central axis O.

[0277] In the first modified example shown in Figures 14 and 15, the body 1 has a double-cylinder structure. That is, the body 1 has an outer cylinder portion 26 and an inner cylinder portion 27 that fits radially inside the outer cylinder portion 26. The outer cylinder portion 26 is cylindrical, extending vertically around the central axis O. The inner cylinder portion 27 is cylindrical, extending vertically around the central axis O. In this modified example as well, the oscillating shaft housing portion 18 is located between the outer and inner circumferences of the body body (body 1).

[0278] The through hole 23 is located in at least the inner cylinder portion 27 of the outer cylinder portion 26 and the inner cylinder portion 27. Specifically, in the illustrated example, the through hole 23 is located across the inner cylinder portion 27 and the outer cylinder portion 26. More specifically, the cylindrical outer peripheral wall of the body 11 is located in the outer cylinder portion 26, the spindle mounting portion 15 is located in the inner cylinder portion 27, and the oscillating shaft housing portion 18, in which the through hole 23 is provided, is located across the outer cylinder portion 26 and the inner cylinder portion 27. The body 11, the spindle mounting portion 15, and the oscillating shaft housing portion 18 are connected to each other and fixed together as a single unit. This first modification also provides the same effects and advantages as the embodiment described above.

[0279] Figures 18 and 19 show a second modified example of the capping head 10 described in the above embodiment. As shown in Figures 18 and 19, in this second modified example, the capping head 10 is equipped with a cylindrical cover 8. The body 1 also has a pocket 11e, a pin insertion hole 11f, and a locking pin 11g. In this second modified example, the body 1 does not have a skirt portion 11h.

[0280] As shown in Figure 19, the pocket 11e is concave, recessed radially inward from the outer circumferential surface 1c of the body 1, and extending vertically. The pocket 11e has a portion recessed radially inward from the outer circumferential surface of the peripheral wall portion 11c, and a portion that is connected to the lower side of this portion and recessed radially inward from the upper portion of the outer circumferential surface of the support projection 17. Multiple pockets 11e are provided arranged in the circumferential direction, although not specifically shown. The number of pockets 11e is the same as the number of support members (oscillating shafts) 3 and the same as the number of biasing members 6.

[0281] The intermediate portion of the support shaft 31, located between the body flange 12 and the lower part of the support projection 17 in the vertical direction, is placed in the pocket 11e. Each biasing member 6 is housed in each pocket 11e.

[0282] The pin insertion hole 11f opens onto the outer circumferential surface of the lower portion of the support projection 17 and extends radially. The pin insertion hole 11f is, for example, circular in shape. Multiple pin insertion holes 11f are provided, spaced apart from each other in the circumferential direction.

[0283] The locking pin 11g is inserted into the pin insertion hole 11f. The locking pin 11g is columnar or cylindrical in shape and extends radially; in this embodiment, for example, it is cylindrical. The locking pin 11g may be fixed in the pin insertion hole 11f by fitting, by screwing, or by adhesive. The locking pin 11g has a portion that protrudes radially outward from the pin insertion hole 11f. That is, the locking pin 11g has a portion that protrudes radially outward from the outer circumferential surface of the support projection 17. Multiple locking pins 11g are provided at intervals from each other in the circumferential direction. For example, three or more locking pins 11g are provided at equal pitches in the circumferential direction.

[0284] The cover 8 is cylindrical with a central axis O and extends vertically. As shown in Figures 18 and 19, the cover 8 surrounds the body 1 from the radial outside to the entire circumference. Specifically, the cover 8 surrounds the body body 11 and the body flange 12 from the radial outside to the entire circumference. The cover 8 also surrounds the peripheral wall portion 11c, the bottom wall portion 11d, the multiple pockets 11e, the multiple biasing members 6, the multiple support projections 17, the multiple roller shaft housing pockets 19, the housing cylinder 16, and a part of the pressure block 2 from the radial outside. The cover 8 also covers the portion of each support member 3 that is placed in the pocket 11e (the intermediate portion of the support shaft 31) from the radial outside.

[0285] The cover 8 has a locking recess 8a. The locking recess 8a penetrates the peripheral wall of the cover 8 radially and extends vertically. The locking recess 8a is a notched or slit-shaped recess. The locking recess 8a opens onto the outer peripheral surface, inner peripheral surface, and lower end surface of the cover 8. Multiple locking recesses 8a are provided at intervals from each other in the circumferential direction. For example, three or more locking recesses 8a are provided at equal pitches in the circumferential direction. The number of locking recesses 8a is the same as the number of locking pins 11g.

[0286] The portion of the locking pin 11g that protrudes from the pin insertion hole 11f is inserted into the locking recess 8a. Specifically, the locking pin 11g faces a pair of inner surfaces of the locking recess 8a that face in the circumferential direction, from the circumferential direction. The locking pin 11g also contacts the inner surface of the locking recess 8a that is located at the upper end and faces downward, from below.

[0287] The cover 8 is fitted onto the body 11 and body flange 12, and the locking pin 11g is locked into the locking recess 8a, thereby fixing the cover 8 to the body 1. The cover 8 can also be removed from the body 1 by moving it upward relative to the body 1. In other words, the cover 8 is detachably attached to the body 1.

[0288] The body 1 and cover 8 are made of metal, for example, an aluminum alloy. Specifically, the body 1 and cover 8 are made of duralumin, for example.

[0289] According to this second modification, the cover 8 prevents the peripheral wall portion 11c, the bottom wall portion 11d, the multiple pockets 11e, the multiple biasing members 6, the intermediate portions of the multiple support shafts 31, the multiple support projections 17, the multiple roller shaft housing pockets 19, the housing cylinder 16, and part of the pressure block 2 (hereinafter sometimes abbreviated as biasing members 6, etc.) from being exposed to the outside of the device. This improves the aesthetic appearance of the device. In addition, the cover 8 prevents contents of beverages, etc. (especially sugars that tend to solidify), oils, and other liquids that splash from outside the capping head 10 toward the body 1 from entering the body 1. This improves maintainability and ensures that the performance (function) of each component, such as the biasing members 6, provided on the body 1 is well maintained.

[0290] Furthermore, in this second modified version, the body 1 and cover 8 are made of lightweight aluminum alloy. This allows for weight reduction while maintaining the overall rigidity of the device.

[0291] Furthermore, although the above-described embodiment showed an example where the capping head 10 has six molding rollers 5, it is not limited to this. The number of molding rollers 5 in the capping head 10 may be eight, for example, or more than six.

[0292] In the embodiment described above, an example was given in which the lower cam 124 of the capping device 120 has only one set of the set consisting of a front lowering section 124a, a first horizontal section 124b, a lowering section 124c, a forming section 124d, an upward section 124e, a second horizontal section 124f, and a rear upward section 124g. However, it is not limited to this, and two sets of the set may be provided arranged in the circumferential direction of the turret. In this case, the lower cam 124 is provided with two sets of the set consisting of a lowering section 124c, a forming section 124d, and an upward section 124e. Then, the series of operations in which each roller 5 of the screw forming roller 5A and the hem rolling roller 5B contacts the circumferential wall 301 of the cap 300, rolls on the circumferential wall 301, and moves away from the circumferential wall 301 is performed twice. In this case, the capping device 120 performs capping by double action.

[0293] In the embodiment described above, a cone cam 7 was given as an example of the cam that the cam follower 4 of the capping head 10 engages with, but it is not limited to this. Although not specifically shown, for example, a configuration in which multiple cams that each cam follower 4 engages with are provided on the upper side of the body 1 may also be used.

[0294] In the above-described embodiment, an example was given in which a cone cam 7, a cam follower 4, and a biasing member 6 are used as the oscillating means for rotating the oscillating shaft 3 around its axis (shaft central axis A) to oscillate the molding roller 5 radially, but the embodiment is not limited to this. As the oscillating means, for example, a servo motor that rotates the oscillating shaft 3 around its axis may be used.

[0295] In the above-described embodiment, a screw-on can B was given as an example of a can having a mouthpiece, but it is not limited to this. As the can to be capped, for example, a screwless bottle can that does not have a screw on the mouthpiece may be used.

[0296] The present invention may be combined in any way that does not depart from the spirit of the invention, as described in the above embodiments and modifications, and the configurations may be added, omitted, substituted, or otherwise modified. Furthermore, the present invention is not limited by the above embodiments, but is limited only by the claims. [Examples]

[0297] The present invention will be described in detail below with reference to examples. However, the present invention is not limited to these examples.

[0298] <Capping confirmation test> As a comparative example 1, a capping device was used that employed a capping head equipped with a total of four forming rollers: two screw forming rollers and two hem-rolling rollers. The capping device was set so that each of the screw forming rollers and hem-rolling rollers would contact the peripheral wall 301 of the cap 300, roll along the peripheral wall 301, and then separate from the peripheral wall 301, in a series of actions performed twice (double action). This capping device was then used to cap a number of screw-on cans B of any desired size with caps 300. Note that, unlike the present invention, the capping head in comparative example 1 is a conventional capping head whose body does not have body recesses or the like.

[0299] In Comparative Example 1, the set diameter of the screw forming roller was φ43.5 mm, and the set diameter of the hem-wrapping roller was φ45.3 mm. The "set diameter" corresponds to the inner diameter dimension (the diameter of the rotational trajectory at the inner end of the roller) of the rotational trajectory obtained by rotating the forming roller around the central axis of the capping head. Depending on the set diameter, the roller tip load at which the forming roller presses the cap circumferential wall radially inward, and the contact length per contact (circumferential length around the cap) of the forming roller against the cap circumferential wall are adjusted.

[0300] Furthermore, as Comparative Example 2, a capping device was used in which each roller of the screw forming roller and the hem rolling roller was set to make contact with the peripheral wall 301 of the cap 300, roll on the peripheral wall 301, and then move away from the peripheral wall 301, in a single action. Capping was performed using this capping device under the same conditions as Comparative Example 1.

[0301] Furthermore, as Embodiment 1 of the present invention, caps 300 were capped onto any number of screw-on cans B using the capping head 10 and capping device 120 described in the above embodiment. Specifically, capping was performed using a capping head 10 equipped with a total of six forming rollers 5, consisting of four screw forming rollers 5A and two hem-rolling rollers 5B, and a capping device 120 in which each roller 5 of the screw forming rollers 5A and hem-rolling rollers 5B contacts the peripheral wall 301 of the cap 300, rolls on the peripheral wall 301, and then separates from the peripheral wall 301, all in a single action. In Example 1, the set diameter of the screw forming roller 5A was set to φ43.5 mm, and the set diameter of the hem rolling roller 5B was set to φ43.5 mm.

[0302] Furthermore, as another embodiment of the present invention, a capping head 10 equipped with a total of six forming rollers 5, consisting of three screw forming rollers 5A and three hem-wrapping rollers 5B, was used. Capping was performed using a capping device 120 in which each roller 5 of the screw forming rollers 5A and hem-wrapping rollers 5B contacts the peripheral wall 301 of the cap 300, rolls on the peripheral wall 301, and then separates from the peripheral wall 301, all in a single action. In Example 2, the set diameter of the screw forming roller 5A was set to φ43.0 mm, and the set diameter of the hem rolling roller 5B was set to φ43.0 mm. All other configurations in Example 2 were the same as those in Example 1.

[0303] For each of Comparative Examples 1 and 2 and Examples 1 and 2, a predetermined number of screw-on cans B were arbitrarily selected from a large number of screw-on cans B capped with caps 300. For each screw-on can B, the following items were measured: "thread depth," "opening angle," "bottom roll," and "thread length." The mean (Ave), maximum (Max), minimum (Min), and standard deviation (σ) were then calculated.

[0304] For more details, the "screw depth" (mm) was measured as follows: Figure 16 is a schematic diagram of a screw illustrating the method for measuring screw depth, showing the number of turns of the screw unfolded on a plane. As shown in Figure 16, the starting point of the screw thread formed on the cap peripheral wall 301 is designated as No. 1, and the threads are numbered No. 1, 2, 3, etc., at 60° intervals around the cap's central axis (can axis) from the start to the end of the thread. The screw depth was then measured at seven points from No. 5 to No. 11, and the maximum value among them was defined as the "screw depth" mentioned above.

[0305] Furthermore, the "opening angle" (°) is the angle of rotation from the start of the operation to rotate the cap 300 attached to the nozzle portion 200 in the opening direction around the can axis until all of the multiple bridges in the cap peripheral wall 301 are broken.

[0306] Furthermore, "hem curling" was measured by sensory evaluation by inspectors (numerical range 1.0 to 5.0). Figures 17(a) to (d) are cross-sectional (longitudinal) images showing the vicinity of the lower end of the peripheral wall 301 of the cap 300 after capping, and are diagrams illustrating the evaluation of hem curling.

[0307] For details, Figure 17(c) shows the state after hem rolling when the hem rolling roller 5B contacts the lower end of the peripheral wall 301 of the cap 300 at the correct position (height) in the vertical direction. In Figure 17(c), there is no gap around the entire circumference between the lower end of the peripheral wall 301 and the lower part of the bulge 201. This state in Figure 17(c) is called "correct (3.0)".

[0308] Furthermore, Figure 17(a) shows the state after hem rolling when the hem rolling roller 5B contacts the lower end of the peripheral wall 301 of the cap 300 at a position higher than the appropriate position described above. In Figure 17(a), a gap is created between the lower end of the peripheral wall 301 and the lower part of the bulge 201, extending from halfway around the cap's central axis to its entire circumference. This state shown in Figure 17(a) is called "hakama (1.0)".

[0309] Furthermore, Figure 17(b) shows the state after hem rolling when the hem rolling roller 5B contacts the lower end of the peripheral wall 301 of the cap 300 at a position between "appropriate" and "skirt" in the vertical direction. In Figure 17(b), there is no gap between the lower end of the peripheral wall 301 and the lower part of the bulge 201, but the tongue piece 301a protrudes downward from the lower end of the peripheral wall 301 in an area of ​​less than 1 / 4 of the circumference around the cap's central axis. This state in Figure 17(b) is called "tongue protrusion (2.5)".

[0310] Furthermore, Figure 17(d) shows the state after hem rolling when the hem rolling roller 5B contacts the lower end of the peripheral wall 301 of the cap 300 at a lower position than the appropriate position described above. In Figure 17(d), a gap is created between the lower end of the peripheral wall 301 and the lower part of the bulge 201, extending from halfway around the cap's central axis to its entire circumference. This state shown in Figure 17(d) is called "loose (5.0)". In the hem roll evaluation, a value between 2.5 and 3.5 within the numerical range of 1.0 to 5.0 is judged as good hem roll, while values ​​below 2.5 and above 3.5 are judged as poor hem roll.

[0311] Furthermore, the "thread length" (mm) was determined by setting the average thread length of the two-turn threaded portion formed on the cap periphery wall 301 of Comparative Example 1 as the reference value (zero), and measuring the length of the threaded portion relative to the reference value using a measuring tape. The results of this capping confirmation test are shown in Table 1.

[0312] [Table 1]

[0313] As shown in Table 1, Comparative Example 1, in which each roller performed molding twice (double action), received a favorable evaluation. In the remarks column of the table, "low screw resistance" indicates that some caps had low torque (reseal torque) when reattaching the cap 300 to the mouthpiece 200 after opening.

[0314] Furthermore, in Comparative Example 2, where each roller performed only one molding cycle (single action), the evaluation was unsatisfactory. Specifically, the thread depth was too shallow, the opening angle was excessive, resulting in a judgment of poor hem wrapping, and the thread length was shorter compared to Comparative Example 1. In the table, "Hinging" in the remarks column indicates that there were instances where a bridge that did not break during opening acted like a hinge, resulting in the cap 300 being connected to the mouthpiece 200 (hinging phenomenon).

[0315] On the other hand, in Examples 1 and 2, good evaluations were obtained despite each roller 5 performing only one molding cycle (single action). In particular, Example 1, which had four screw-forming rollers 5A and two hem-rolling rollers 5B, achieved a screw depth deeper than that of Comparative Example 1, which used double action, and yielded particularly good results.

[0316] Specifically, in Example 1, despite being a single-action capping system, the "thread depth" was significantly greater (deeper) compared to Comparative Example 1, which was a double-action system. The "hem wrapping" evaluation was also better (all results were "appropriate (3.0)"), and the thread length was also longer.

[0317] <Confirmation of roller molding tip load, etc.> Here, with reference to Tables 2 and 3 below, the roller forming tip loads, etc., for Example 1 and Comparative Examples 1 and 3 will be explained in more detail. Comparative Example 3 is the same as Comparative Example 1, except that the set diameter of the screw forming roller 5A is φ43.5 mm and the set diameter of the hem-wrapping roller 5B is φ43.5 mm. In addition, "RO" in Tables 2 and 3 represents the screw forming roller 5A, and "PP" represents the hem-wrapping roller 5B. Furthermore, as described in the above-mentioned embodiments, the capping head 10 of Example 1 is more compact in various dimensions compared to the capping heads of Comparative Examples 1 and 3. Specifically, Example 1 has smaller dimensions in various aspects compared to Comparative Examples 1 and 3, such as the outer diameter of the body 1, the dimensions of the upper arm 32 and lower arm 33 in the shaft diameter direction, the diameter of the roller body 52, and the diameter of the support shaft 31. Also, Example 1 has a smaller spring constant of the biasing member 6 compared to Comparative Examples 1 and 3.

[0318] [Table 2]

[0319] [Table 3]

[0320] In Table 2, "Setup (N·m)" refers to the torque setting value around the support shafts 31 of the screw forming roller 5A and the hem rolling roller 5B before forming on the cap perimeter wall 301 (i.e., when each roller 5 is separated from the cap perimeter wall 301). Specifically, it represents the torque of each roller 5A and 5B when the rolling elements 42 of the cam follower 4 are in contact with the large-diameter rolling surface 72 of the cone cam 7.

[0321] Furthermore, "Cap Processing Start (N·m)" in Table 2 represents the torque at the start of processing when each roller 5A and 5B, in the setup described above, rotates around axis A of the support shaft 31 and contacts the cap wall 301, assuming the diameter (outer diameter) of the cap perimeter wall 301 before forming is φ38 mm.

[0322] Furthermore, in Table 2, "Cap Processing Completion (N·m)" represents the torque when the thread depth reaches 0.6 mm (i.e., processing is complete) for the thread forming roller 5A, and the torque when the diameter of the lower end of the cap peripheral wall 301 reaches φ35.9 mm (i.e., processing is complete) for the hem-wrapping roller 5B.

[0323] Furthermore, the "RO roller contact distance (mm)" in Table 3 represents the distance (at the start and end of processing) between the contact point between the roller body 52 of the screw forming roller 5A and the cap peripheral wall 301, and the central axis A of the support shaft 31 that supports the screw forming roller 5A, as viewed from the axial direction (downward) of the central axis O, as shown in Figure 4.

[0324] Furthermore, the "PP roller contact distance (mm)" in Table 3 refers to the distance (at the start and end of processing) between the contact point between the roller body 52 of the hem-wrapping roller 5B and the cap peripheral wall 301, and the central axis A of the support shaft 31 that supports the hem-wrapping roller 5B, as viewed from the axial direction as shown in Figure 4.

[0325] Furthermore, "RO forming tip load (N)" in Table 3 refers to the load at the contact point (tip) of the outer circumference of the roller body 52 of the screw forming roller 5A that contacts the cap peripheral wall 301 (at the start and end of processing).

[0326] Furthermore, "PP molding tip load (N)" in Table 3 refers to the load at the contact point (tip) of the outer edge of the roller body 52 of the hem-wrapping roller 5B that contacts the cap peripheral wall 301 (at the start and end of processing).

[0327] As shown in Table 2, in Comparative Examples 1 and 3, the RO torques at "cap processing start" and "cap processing end" exceeded 3.0 N·m, whereas in Example 1, the RO torques were 3.0 N·m or less, specifically 2.5 N·m or less. Furthermore, in Comparative Examples 1 and 3, the PP torque at "cap processing start" and "cap processing end" exceeded 2.5 N·m, whereas in Example 1, the PP torque was 2.5 N·m or less, specifically 2.0 N·m or less.

[0328] Furthermore, as shown in Table 3, in Comparative Examples 1 and 3, the "RO molding tip load" exceeds 110 N, whereas in Example 1, the "RO molding tip load" is 110 N or less, specifically 90 N or less. Furthermore, in Comparative Examples 1 and 3, the "PP molding tip load" exceeded 90N, whereas in Example 1, the "PP molding tip load" was 90N or less, specifically 75N or less.

[0329] As explained in the above <Capping Confirmation Test> and Table 1, the capping performance of Example 1 is superior to that of the comparative example. [Industrial applicability]

[0330] This invention no Ki The capping head, spindle assembly, capping device, and capping system allow for a simplified body shape, increased body strength, and reduced weight. Therefore, they have industrial applicability. [Explanation of symbols]

[0331] 1…Body, 1c…Outer surface (outer wall), 2…Pressure block, 3…Oscillating shaft, 4…Cam follower, 5…Forming roller, 5A…Thread forming roller, 5B…Hem-wrapping roller, 6…Biasing member, 7…Cone cam (cam), 10…Capping head, 11…Body body, 12…Body flange, 15…Spindle mounting part, 18…Oscillating shaft housing part, 23…Through hole, 23a…Body hole, 23b…Flange hole, 23c…Housing hole, 23d…Bearing hole, 24,25…Bearing member, 31…Support shaft, 32…Upper arm, 32a…Upper clamp part, 33…Lower arm, 33a… Lower clamp section, 36...Deformation assist groove, 80...Spindle assembly, 81...Lifting shaft, 83...Upper cam follower, 85...Spindle, 86...Spindle gear, 90...Lifting cylinder, 91...Lower cam follower, 100...Capping system, 110...Filler, 120...Capping device, 121...Turret, 122...Fixed gear, 123...Upper cam, 124...Lower cam, 200...Mouthpiece section, 300...Cap, 301...Circumferential wall, A...Shaft central axis (axis of the oscillating shaft), B...Threaded can (can), D...Conveying direction, O...Central axis, T...Turret axis

Claims

1. A capping head for attaching a top-cylindrical cap to the mouth of a bottom-cylindrical can, The capping head body used in the aforementioned capping head, A molding roller positioned on the lower side of the body, A pivoting shaft that causes the molding roller to swing toward the peripheral wall of the cap, A cam follower is positioned on the upper side of the body and engages with the cam, The system includes a biasing member that biases the cam follower and the molding roller radially inward via the aforementioned pivoting shaft, The aforementioned body is A cylindrical body, A spindle mounting portion is located inside the main body and attached to the spindle, The body comprises a pivot shaft housing positioned between the outer and inner circumferences of the main body, The aforementioned body is a single cylindrical body having a cylindrical outer surface, The pivot shaft housing is arranged around the spindle mounting portion and has a through hole through which the pivot shaft, which causes the molding roller to pivot toward the peripheral wall of the cap, is inserted. The aforementioned through hole penetrates the main body in the vertical direction, The body, the spindle mounting portion, and the oscillating shaft housing portion are connected to each other. The biasing member surrounds a portion of the pivot shaft in the vertical direction around the axis of the pivot shaft and is housed in the through hole. The biasing member is housed in the through-hole without being exposed on the outer circumference of the body. Capping head.

2. A capping head for attaching a top-cylindrical cap to the mouth of a bottom-cylindrical can, The capping head body used in the aforementioned capping head, A molding roller positioned on the lower side of the body, A pivoting shaft that causes the molding roller to swing toward the peripheral wall of the cap, A cam follower is positioned on the upper side of the body and engages with the cam, The system includes a biasing member that biases the cam follower and the molding roller radially inward via the aforementioned pivoting shaft, The aforementioned body is A cylindrical body, A spindle mounting portion is located inside the main body and attached to the spindle, The body comprises a pivot shaft housing positioned between the outer and inner circumferences of the main body, The aforementioned body is a single cylindrical body having a cylindrical outer surface, The pivot shaft housing is arranged around the spindle mounting portion and has a through hole through which the pivot shaft, which causes the molding roller to pivot toward the peripheral wall of the cap, is inserted. The aforementioned through hole penetrates the main body in the vertical direction, The body, the spindle mounting portion, and the oscillating shaft housing portion are connected to each other. The biasing member surrounds a portion of the pivot shaft in the vertical direction around the axis of the pivot shaft and is housed in the through hole. The aforementioned oscillating shaft is, A support shaft extending in the vertical direction, An upper arm connecting the support shaft and the cam follower, It has a lower arm that connects the support shaft and the molding roller, The upper arm has an upper clamp portion that surrounds the support shaft around its axis and is deformable to press against the outer surface of the support shaft. The lower arm has a lower clamp portion that surrounds the support shaft around its axis and is deformable to press against the outer surface of the support shaft. At least one of the upper clamp portion and the lower clamp portion has a deformation assist groove that is arranged on the circumferential surface of the clamp portion and extends in the vertical direction. Capping head.

3. The aforementioned through holes are provided in multiple locations, spaced apart from each other in the circumferential direction. Each of the through holes has an opening that opens to the upper end surface of the body, The circumferential dimension of the opening decreases as it moves radially inward. A capping head according to claim 1 or 2.

4. The aforementioned opening has a triangular hole shape when viewed from above. The capping head according to claim 3.

5. The body has a recess that extends downward from the upper surface of the body and accommodates at least the lower end of the cam. The radial inner end of the opening opens to the inner circumferential surface of the body recess. The capping head according to claim 3.

6. The aforementioned body is The aforementioned body and, It has an annular body flange fixed to the upper end of the body body, The aforementioned through hole is The aforementioned body has a hole that penetrates it vertically, The body flange has a flange hole that penetrates vertically, The biasing member is positioned in the hole of the main body. A capping head according to claim 1 or 2.

7. The aforementioned hole in the main body is The housing hole in which the biasing member is arranged, It has a bearing hole located at the lower end of the main body hole, The pivot shaft is rotatably supported by the body via a pair of bearing members provided in the flange hole and the bearing hole. The capping head according to claim 6.

8. The biasing member is a torsion coil spring that extends spirally around the axis of the pivot shaft, Of the two ends of the biasing member in the vertical direction, the upper end is locked to the body flange, and the lower end is locked to the pivot shaft. The capping head according to claim 6.

9. At least a portion of the body is made of aluminum alloy, engineering plastic, or FRP. A capping head according to claim 1 or 2.

10. A pressure block is provided on the lower side of the body and presses against the top wall of the cap, A capping head according to claim 1 or 2.

11. The molding rollers are arranged in a circumferential direction, with six or more rollers provided. Multiple molding rollers, Multiple thread forming rollers are provided on the peripheral wall of the cap to form a threaded portion that screws into the mouthpiece portion, The cap includes at least one hem-rolling roller for forming a hem around the lower end of the peripheral wall of the cap onto the mouthpiece, The number of screw forming rollers is greater than the number of hem rolling rollers. A capping head according to claim 1 or 2.

12. The screw forming rollers that are adjacent to each other in the circumferential direction are offset from each other in the vertical direction. The capping head according to claim 11.

13. Multiple molding rollers are provided arranged in the circumferential direction. The biasing members are provided in the same number as the molding rollers, arranged in a plurality in the circumferential direction. The number of through holes is the same as the number of biasing members, and multiple holes are provided arranged in the circumferential direction. A capping head according to claim 1 or 2.

14. A capping head according to claim 1 or 2, A lifting shaft extending in the vertical direction, to which a pressure block that presses against the top wall of the cap is attached, A spindle that is cylindrical in shape, has the lifting shaft inserted inside, and to which the body is attached, It comprises a cylindrical lifting cylinder into which the lifting shaft and the spindle are inserted, The lifting shaft has an upper cam follower that moves the lifting shaft in the vertical direction. The spindle has a spindle gear that rotates the spindle around its central axis. The aforementioned lifting cylinder is A cylindrical cam, The system includes a lower cam follower that moves the lifting cylinder in the vertical direction, Spindle assembly.

15. A turret that rotates around its axis, The spindle assembly according to claim 14, which is disposed on the outer circumference of the turret, A fixed gear that meshes with the spindle gear and extends around the turret shaft, An upper cam extending around the turret shaft and engaging with the upper cam follower, It comprises a lower cam extending around the turret axis and with which the lower cam follower engages, Capping device.

16. A filler that fills the can with contents, The capping device according to claim 15, wherein the can discharged from the filler is supplied, The direction in which the can is transported from the filler toward the capping device is such that, when viewed from the turret axis direction, it follows the tangent to the outer circumference of the turret. Capping system.

Images