JP4397390B2 - Manufacturing method and manufacturing apparatus for manufacturing lid with packing - Google Patents

Description

  The present invention relates to a method for manufacturing a container lid with packing in which packing is integrally formed along a fitting groove, and an apparatus for manufacturing a container lid with packing that can be suitably used for the method.

  Metal containers called pail cans are widely used for storing or transporting contents such as medicines, paints or oils. The container body of a pail can usually has a bottomed cylindrical shape, and its upper opening is covered with a circular container lid. A fitting groove for fitting the opening end of the container main body is provided in an annular shape at a location along the outer edge of the lower surface of the container lid, and the inside of the fitting groove has airtightness inside the container. Packing is provided so that liquid tightness can be maintained.

  Such a container lid with packing is conventionally made by manually fitting an annular packing obtained by connecting both ends of a foam formed in advance into a linear shape into a fitting groove provided on the container lid. It was manufactured. As the foam material, thermoplastic resin and rubber are usually employed. Although this method has the advantage that it is easy to form a packing with excellent solvent resistance and chemical resistance in the fitting groove of the container lid, it is necessary to manually fit the packing, etc. It was difficult to shorten the manufacturing time. For this reason, it was difficult to keep the manufacturing cost of the container lid with packing low.

  In view of such a situation, in recent years, molten rubber or thermosetting resin added with a foaming agent is discharged from the nozzle and poured into the fitting groove of the container lid, and then the entire container lid is heated. A method in which rubber or thermosetting resin in the fitting groove is foamed and simultaneously crosslinked by heating in a furnace or the like has become mainstream (for example, Patent Document 1 and Patent Document 2). This method is excellent in workability because it does not require time and effort to fit the packing, but since a large heating furnace is required, it is difficult to save space and energy in the manufacturing facility for the container lid with packing. there were. Further, this method requires heating the container lid for several minutes in a heating furnace, so that it is difficult to shorten the manufacturing time.

JP 2005-014214 A JP 2003-147111 A

  The present invention has been made to solve the above-mentioned problems, and can easily form a packing in a fitting groove provided in a container lid to reduce manufacturing time, and also saves space in manufacturing equipment. The present invention provides a method for manufacturing a container lid with packing, which can also realize energy saving and energy saving. It is also an object of the present invention to provide an apparatus for manufacturing a container lid with packing, which can be suitably used in the method for manufacturing a container lid with packing.

  The above problem is that the thermoplastic resin heated and melted by the extruder is linearly extruded from the nozzle and poured into a fitting groove provided on one surface of the container lid, so that the packing is integrated along the fitting groove. A method for producing a container lid with packing, wherein a thermoplastic resin to which a foaming agent is added is heated and melted inside an extruder, and the heated and melted thermoplastic resin is foamed immediately after being discharged from a nozzle to form a container. The problem is solved by providing a method for manufacturing a container lid with packing, wherein the fitting groove is filled with foam without heating the entire lid.

  Here, “foaming immediately after being discharged from the nozzle” refers to foaming and increasing the volume by releasing the pressure of the molten resin in a pressurized state inside the nozzle. This includes not only the case where bubbles are newly generated by being discharged from the nozzle, but also the case where the volume of bubbles generated inside the nozzle is increased.

  Thereby, it is possible to foam the thermoplastic resin without performing a treatment such as heating the thermoplastic resin (packing) poured into the fitting groove together with the container lid. Therefore, it is possible to form the packing in the fitting groove without performing complicated manual work such as fitting the packing into the fitting groove of the container lid. In addition, since it is not necessary to separately provide a heating furnace or the like, it is possible to realize space saving and energy saving of a manufacturing facility for a container lid with packing. Further, the packing and the container lid are integrated, and it is possible to obtain a container lid with packing excellent in sealing performance.

  At this time, it is preferable to press-fit a foaming agent made of gas or liquid into the thermoplastic resin heated and melted inside the extruder. Gas or liquid blowing agents are not only available at low cost, but also have excellent foamability.

  The expansion ratio of the thermoplastic resin is not particularly limited, but if it is too low, the packing formed in the fitting groove becomes too hard and it may be difficult to fit the container lid into the container body. On the other hand, if the expansion ratio of the thermoplastic resin is too high, the sealing performance and strength may be reduced. For this reason, the expansion ratio of the thermoplastic resin is usually 2 to 30 times.

  The thermoplastic resin used as the raw material for the packing is not particularly limited, but polyolefin is preferably used. This is because polyolefin is excellent in flexibility, chemical resistance, moldability and the like and is low in cost.

  It is also preferable that the thermoplastic resin is discharged from the nozzle fixed in position and poured into the fitting groove while rotating the container lid provided with the fitting groove in an annular shape around the central axis of the fitting groove. Thereby, it becomes possible to further simplify the manufacturing equipment of the container lid with packing.

  It is also preferable to heat the overlapping portion of the thermoplastic resin poured into the fitting groove and weld the overlapping portion (welding step). At this time, if a hot plate is used as a heating means for melting the thermoplastic resin, the hot plate is likely to be contaminated with the resin, and it may be difficult to perform repeated melting operations. In addition, if a heating means using heat radiation is used, the production rate may be reduced. For this reason, it is preferable to perform a welding process by spraying a hot air on the said overlap part.

  After that, it is also preferable to press the overlapping portion of the start and end of the thermoplastic resin in the depth direction of the fitting groove (pressing step). As a result, the contents can be prevented from leaking from the gap between the start and end of the thermoplastic resin (packing) poured into the fitting groove, and the air tightness and liquid tightness of the packing can be further improved. Is possible.

  By pressing the thermoplastic resin poured into the fitting groove in the depth direction of the fitting groove with a mold along the fitting groove, a recess or a flat part along the longitudinal direction is formed in the packing. Is also preferable. Moreover, it is also preferable to form the nozzle outlet in a non-circular shape and to form a recess or a flat portion along the longitudinal direction in the packing. By these methods, it is possible not only to make the cross-sectional shape of the packing concave or flat so that the opening end of the container body can be easily fitted in the fitting groove, but also to perform the above pressing step at the same time. It is also an advantage of the manufacturing method of the container lid with packing according to the present invention that the packing having such a shape can be efficiently produced.

  A plurality of nozzles are provided, and thermoplastic resin is alternately discharged from one set of nozzles and the other set of nozzles, so that the fitting groove of the container lid below the one set of nozzles and the other set of nozzles It is also preferable that thermoplastic resin is alternately poured into the fitting groove of the container lid located below so that packing can be sequentially formed on the plurality of container lids. When sequentially forming packings for a plurality of container lids, if the operation of the extruder is stopped each time the container lid into which the thermoplastic resin is poured is changed, the physical properties of the thermoplastic resin change while it is stopped. Therefore, the packing formed in the fitting groove becomes non-uniform, and the gas tightness, liquid tightness, and strength of the packing may be reduced. By adopting such a configuration, the operation in the extruder can be performed. Since it can be performed continuously, it is possible to eliminate the above problems.

  Further, the above-described problem is that a container with packing that integrally forms a packing along the fitting groove by extruding a thermoplastic resin linearly from a nozzle and pouring it into the fitting groove provided on one surface of the container lid. A lid manufacturing apparatus for a thermoplastic resin charging part for charging a thermoplastic resin, an extruder for heating and melting the thermoplastic resin, and a thermoplastic resin heated and melted inside the extruder A foaming agent press-fitting part for press-fitting a gas or liquid foaming agent, a nozzle for discharging the thermoplastic resin heated and melted inside the extruder to the outside of the extruder, and a container lid below the nozzle A container lid supply means for supplying, and a container lid moving means for moving the container lid below the nozzle so that the thermoplastic resin extruded from the nozzle flows along the fitting groove. Characteristic packing Also solved by providing an apparatus for manufacturing a container lid can. This manufacturing apparatus for a container lid with packing can suitably execute the above-described method for manufacturing a container lid with packing.

  As described above, according to the present invention, the packing can be easily formed in the fitting groove provided in the container lid, so that not only the production efficiency is high, but also the space saving and the energy saving of the manufacturing equipment can be realized. It becomes possible to provide the manufacturing method of the container lid with packing. Moreover, it becomes possible to provide the manufacturing apparatus of the container lid with packing which can be used suitably for the manufacturing method of these container lids with packing.

  Preferred embodiments of the method for manufacturing a container lid with packing and the method for manufacturing a container lid with packing according to the present invention will be described more specifically with reference to the drawings. FIG. 1 is a cross-sectional view showing a state in which a thermoplastic resin 120 is poured into the fitting groove 111 of the container lid 110 using the method and apparatus for producing a container lid with packing according to the present invention. FIG. 2 is a cutaway perspective view showing a container lid 100 with packing manufactured by using the method and apparatus for manufacturing a container lid with packing according to the present invention.

  As shown in FIG. 1, the manufacturing method of the container lid with packing according to the present embodiment is such that the thermoplastic resin 120 is linearly extruded from the nozzle 40 and poured into a fitting groove 111 provided on one surface of the container lid 110. The packing is integrally formed along the fitting groove 111. The thermoplastic resin 120 is normally charged into the thermoplastic resin charging unit 10 in the form of pellets and is heated and melted inside the extruder 20. A gas or liquid foaming agent 121 is added to the thermoplastic resin 120 heated and melted inside the extruder 20. Addition of the foaming agent 121 is performed by press-fitting the foaming agent 121 into the extruder 20 from the foaming agent press-fitting portion 30.

  The container lid 110 used in the method and apparatus for producing a container lid with packing according to the present invention may be a square one, but in this embodiment, a circular one is used as shown in FIG. ing. An annular fitting groove 111 is provided on one side of the container lid 110 along its outer edge so that it can be fitted into the open end of a bottomed cylindrical container body (not shown). It has become. The container lid 110 of FIG. 2 is drawn upside down so that the fitting groove 111 provided on the lower surface thereof faces upward.

  In this form, the container lid 110 not only has a risk of falling into the inside of the container body, but also easily forms a packing in the fitting groove 111, and it is relatively easy to maintain the air tightness and liquid tightness of the container body. Therefore, it is most widely used as a lid of a pail can for storing or transporting contents such as chemicals, paints or oils. The container lid 110 is supplied below the nozzle 40 at a predetermined timing by a container lid supply means (not shown). The container lid supply means is not particularly limited as long as it can supply the container lid 110 below the nozzle 40, but in the present embodiment, a belt conveyor is used.

  The kind of the thermoplastic resin 120 (the thermoplastic resin used as the raw material for the packing) to be charged into the thermoplastic resin charging unit 10 is not particularly limited, and examples thereof include polyolefin, polyvinyl chloride, polyvinyl acetate, polyester, and polyamide. . A thermoplastic elastomer can also be used, and various thermoplastic elastomers such as polyurethane, polyolefin, polystyrene, polyester, and polyamide can be used. Of these, it is preferable to use polyolefin. Polyolefin is generally preferable because it is excellent in flexibility, chemical resistance and moldability, is low in cost, and does not generate harmful gas even when incinerated upon disposal. As the polyolefin, polyethylene, polypropylene and the like are used, and polyethylene is particularly preferable. As the polyethylene, high-density polyethylene, low-density polyethylene, LLDPE, and the like are used, and low-density polyethylene is preferable from the viewpoint of flexibility, moldability, and foamability. Polyethylene and polypropylene may be a copolymer in which other monomers are copolymerized. In this embodiment, among these resins, low density polyethylene is employed. The thermoplastic resin 120 may be crosslinked as long as the melt moldability is not hindered. Moreover, you may mix | blend a crosslinked rubber particle, an inorganic filler, etc. with the thermoplastic resin 120. FIG.

  The type of the foaming agent 121 added to the thermoplastic resin 120 is not particularly limited. A powdery material may be used, and an organic chemical foaming agent such as azodicarboxylic acid amide or an inorganic chemical foaming agent such as bicarbonate can be used. Moreover, the microcapsule which included the foaming component can also be used. Such a powdery foaming agent is put into the thermoplastic resin charging unit 10 as a powder or as a master batch pellet at the same time as the thermoplastic resin pellet.

  On the other hand, considering the acquisition cost and foamability, it is preferable to press-fit a gas or liquid foaming agent into the thermoplastic resin 120 heated and melted inside the extruder 20. Among these, hydrocarbon compounds having 3 to 6 carbon atoms are preferable because they have a low boiling point and can be easily foamed even at atmospheric pressure. Examples of the hydrocarbon compound having 3 to 6 carbon atoms include propane (carbon number 3), butane (carbon number 4), pentane (carbon number 5), and hexane (carbon number 6). In particular, butane is preferable because it easily forms single bubbles and can make the packing excellent in air tightness and liquid tightness.

  The expansion ratio of the thermoplastic resin 120 is not particularly limited, but if it is too low, the packing formed in the fitting groove 111 becomes too hard and it may be difficult to fit the container lid 110 into the container body. For this reason, the expansion ratio of the thermoplastic resin 120 is normally set to 2 times or more. The expansion ratio of the thermoplastic resin 120 is preferably 5 times or more, and more preferably 10 times or more. On the other hand, if the expansion ratio of the thermoplastic resin 120 is too high, communication bubbles are likely to be formed in the packing, and the air tightness and liquid tightness of the container may not be maintained. In addition, the strength of the packing may be reduced. For this reason, the expansion ratio of the thermoplastic resin 120 is normally 30 times or less. The expansion ratio of the thermoplastic resin 120 is preferably 20 times or less, and more preferably 15 times or less.

  The thermoplastic resin 120 heated and melted inside the extruder 20 and added with the foaming agent 121 is discharged from the nozzle 40 and poured into an annular fitting groove 111 provided on one side of the container lid 110. The melting temperature of the thermoplastic resin 120 is usually 150 to 300 ° C. At this time, since the foaming agent 121 added to the thermoplastic resin 120 is foamed immediately after being discharged from the nozzle 40, the thermoplastic resin 120 becomes a foam and is filled in the fitting groove 111. Form. In this embodiment, the thermoplastic resin 120 is poured into the fitting groove 111 while the container lid moving means 60 rotates the container lid 110 around the central axis (axis L in FIG. 1) of the fitting groove 111. It is like that. For this reason, the thermoplastic resin 120 discharged from the position-fixed nozzle 40 can be neatly poured along the fitting groove 111. At this time, if the tip of the nozzle 40 is separated from the container lid 110, it is difficult to flow the thermoplastic resin 120 into the fitting groove 111. Therefore, the tip of the nozzle 40 may be arranged near the container lid 110. . This makes it possible to fill the fitting groove 111 while foaming the thermoplastic resin 120 without forming a large gap inside the fitting groove 111.

  In this embodiment, when the thermoplastic resin 120 is poured into the fitting groove 111 of the container lid 110, the start end of the thermoplastic resin 120 poured into the fitting groove 111 by a heating means (hot air blowing means) (not shown). The hot air is blown onto the overlapping portion between the terminal and the terminal, and the overlapping portion is welded (welding step). This welding process may be performed when the overlapping portion is below the nozzle 40, but the nozzle 40 may interfere. In such a case, after the pouring of the thermoplastic resin 120 is completed, the container lid 110 is rotated by a predetermined angle by the container lid moving means 60, and the overlapping portion is shifted from the lower side of the nozzle 40.

  Further, in this embodiment, when the above-described welding process is completed, the overlapping portion between the start end and the end end of the thermoplastic resin 120 poured into the fitting groove 111 is formed in the depth of the fitting groove 111 by pressing means (not shown). It is pressed in the vertical direction (pressing step). For this reason, it becomes possible to make the start end and termination | terminus of the thermoplastic resin 120 poured into the fitting groove | channel 111 closely_contact | adhere, and to prevent the contents of a container from leaking from the clearance gap between the start end and termination | terminus of the thermoplastic resin 120 Be able to. This pressing step may be performed when the overlapping portion is below the nozzle 40 as in the hot air blowing step. However, since the nozzle 40 may be in the way, the container lid moving means 60 causes the container lid 110 to move. Is rotated by a predetermined angle to shift the overlapping portion from below the nozzle 40.

  The container lid 110 that has finished the hot air spraying step and the pressing step is removed from below the nozzle 40 by a container lid discharging means (not shown). Thereby, the container lid 100 with packing as shown in FIG. 2 can be obtained. When the container lid 110 (the container lid 100 with packing) is removed from below the nozzle 40, the next container lid 110 is supplied below the nozzle 40 by the container lid supply means.

  Then, the other embodiment of the manufacturing method and manufacturing apparatus of the container lid with packing of this invention is demonstrated. FIG. 3 is a plan view showing a state in which the thermoplastic resin 120 is poured into the fitting groove 111 of the container lid 110 using the manufacturing apparatus for a container lid with packing according to another embodiment. FIG. 4 is a front view showing a state in which the thermoplastic resin 120 is poured into the fitting groove 111 of the container lid 110 using the container lid manufacturing apparatus for packing according to another embodiment. FIG. 5 is a cross-sectional view showing a state where the shutter plate 80 provided around the nozzle 40 in FIG. 4 is moved to the limit point (position A) on one end side (left end side in FIG. 5). FIG. 6 is a cross-sectional view showing a state in which the shutter plate 80 provided around the nozzle 40 in FIG. 4 is moved to the intermediate position. 7 is a cross-sectional view showing a state where the shutter plate 80 provided around the nozzle 40 in FIG. 4 is moved to the limit point (position B) on the other end side (right end side in FIG. 5).

  3 and 4 includes a plurality of sets of nozzles 40. The thermoplastic resin 120 is supplied from one set of nozzles 41 and 42 and the other set of nozzles 43 and 44. By alternately discharging, the fitting groove 111 of the container lid 110 below the one set of nozzles 41 and 42 and the fitting groove 111 of the container lid 110 below the other set of nozzles 43 and 44 are thermoplastic. The resin 120 can be poured alternately. Therefore, the structure is such that a plurality of packing-equipped container lids can be sequentially manufactured at a time. In this case, the container lid supply means 50 (FIG. 3) supplies the container lid 110 below the one set of nozzles 41 and 42 and the line below the other set of nozzles 43 and 44. A line that can be driven independently from the line to be used is used. Here, an example is shown in which a total of four nozzles 41 to 44 are provided for each two sets, but the number of nozzles 40 is not limited to this and can be changed as appropriate.

  As shown in FIGS. 4 and 5 to 7, the nozzles 41 to 44 are provided at predetermined intervals along the longitudinal direction on the lower surface of the pipe-like nozzle base 70 arranged in the horizontal direction. For this reason, the thermoplastic resin 120 extruded from the extruder 20 enters the inside of the nozzle base 70 from the center of the nozzle base 70 and is divided into left and right parts, and then is discharged downward from the nozzles 41 to 44. Yes. The length of the nozzle base 70 in the horizontal direction and the interval at which the nozzles 41 to 44 are disposed are not particularly limited. However, if the length is too long, the yield of the thermoplastic resin 120 is reduced or the nozzles 41 to 44 are discharged. Since there is a possibility that a problem such as a large difference in the physical properties of the thermoplastic resin 120 may occur, it is preferable to set as short as possible.

  The mechanism for switching the nozzle 40 that discharges the thermoplastic resin 120 is not particularly limited, and an independent valve or the like may be provided for each of the nozzles 41 to 44. In the example of FIGS. 5 to 7, the nozzle 40 that discharges the thermoplastic resin 120 can be switched by sliding the shutter plate 80 provided with the holes 81 to 84 at a predetermined interval in the horizontal direction. Yes. By adopting such a configuration, switching of the nozzle 40 can be realized with a simpler structure.

  That is, as shown in FIG. 5, when the shutter plate 80 is moved to the A position, the thermoplastic resin 120 can be discharged from the nozzles 41 and 42, and as shown in FIG. When the shutter plate 80 is moved to the B position, as shown in FIG. 7, the thermoplastic resin 120 is not discharged from any of the nozzles 41 to 44. The resin 120 can be discharged.

  Further, in this manufacturing method of the container lid with packing, the container lid 110 in which the fitting groove 111 is filled with the thermoplastic resin 120 below the one set of nozzles 41 and 42 is connected to the other set of nozzles 43 and 44. While the thermoplastic resin 120 is being discharged, the hot air spraying step and the pressing step are completed and removed from below the nozzles 41 and 42 by the container lid discharging means 90. When the container lid 110 is removed from below the nozzles 41, 42, the next container lid 110 is supplied below the nozzles 43, 44 by the container lid supply means 50. For this reason, packing can be sequentially formed with respect to a plurality of container lids 110 without delaying the thermoplastic resin 120, and the production of the container lid 100 with packing can be efficiently performed. It is like that.

  By the way, in the example shown in FIGS. 5 to 7, one set of nozzles 41 and 42 is arranged on one end side (left end side) of the nozzle base 70, and the other set of nozzles 43 and 44 is other than the nozzle base 70. Although arrange | positioned at the end side (right end side), arrangement | positioning of the nozzles 41-44 is not limited to this. For example, as shown in FIGS. 8 to 10, it is also preferable to arrange the nozzle 41, the nozzle 43, the nozzle 42, and the nozzle 44 in this order from one end (left end) to the other end (right end) of the nozzle base 70. Thus, by alternately arranging one set of nozzles 41 and 42 and another set of nozzles 43 and 44, when one set of nozzles 41 and 42 is discharging the thermoplastic resin 120, The thermoplastic resin 120 can be allowed to flow to one end side and the other end side of the nozzle base 70 in any case when the other groups of nozzles 43 and 44 are discharging the thermoplastic resin 120. Therefore, it is possible to further reduce the variation in physical properties of the thermoplastic resin 120 discharged from the nozzles 41 to 44.

  The cross-sectional shape of the packing formed in the fitting groove 111 of the container lid 110 is not limited to a circle as shown in FIG. 11, and various shapes (non-circular shapes) can be selected. For example, a semicircular shape (FIG. 12), a crescent shape (FIG. 13), a gourd shape, an arc shape, a broken line shape, and the like can be used. Thereby, it becomes possible to form the recessed part or flat part along a longitudinal direction in packing, and can make it easy to engage | insert the opening end of a container main body in the fitting groove | channel 111. FIG. The cross-sectional shape of the packing can be set by changing the shape of the discharge port of the nozzle 40. For example, when the cross-sectional shape of the packing is to be semicircular, the discharge port of the nozzle 40 may be semicircular. Further, the number of discharge ports provided in one nozzle 40 is not limited to one and may be plural. For example, when a thermoplastic resin is poured into the fitting groove 111 from two discharge ports arranged close to each other, a gourd-shaped packing can be formed.

  In addition, the recess along the longitudinal direction of the packing is formed along the fitting groove 111 after the thermoplastic resin 120 is poured into the fitting groove 111 of the container lid 110 and then the thermoplastic resin 120 poured into the fitting groove 111 is poured. It can also be formed by pressing in the depth direction of the fitting groove 111 with a mold. As a result, not only can the recess be formed in the packing, but the above pressing step can be performed simultaneously. A dedicated mold may be prepared at this time, but it is preferable to use the container lid 110 as a mold. That is, as shown in FIG. 14, a plurality of container lids 110 into which the thermoplastic resin 120 has been poured are overlapped in the fitting grooves 111, and the lower side of the container lid 110 is placed while the thermoplastic resin 120 is in a high temperature state. By pressing the thermoplastic resin 120 poured into the fitting groove 111 with the upper surface (lower surface in FIG. 14) of the upper container lid 110, a recess along the longitudinal direction can be formed in the packing.

It is sectional drawing which showed a mode that a thermoplastic resin was poured into the fitting groove | channel of a container lid using the manufacturing method and manufacturing apparatus of a container lid with packing of this invention. It is the fracture | rupture perspective view which showed the container lid with packing manufactured using the manufacturing method and manufacturing apparatus of the container lid with packing of this invention. It is the top view which showed a mode that the thermoplastic resin was poured into the fitting groove | channel of a container lid using the manufacturing apparatus of the container lid with packing of other embodiments. It is the front view which showed a mode that a thermoplastic resin was poured into the fitting groove | channel of a container lid using the manufacturing apparatus of the container lid with packing of other embodiment. FIG. 5 is a cross-sectional view illustrating a state in which a shutter plate provided around the nozzle in FIG. 4 is moved to a limit point (position A) on one end side (left end side). FIG. 5 is a cross-sectional view showing a state in which a shutter plate provided around the nozzle in FIG. 4 is moved to an intermediate position. FIG. 5 is a cross-sectional view illustrating a state in which a shutter plate provided around the nozzle in FIG. 4 is moved to a limit point (position B) on the other end side (right end side). It is sectional drawing which showed the state which moved the shutter plate provided in the periphery of the nozzle in the manufacturing apparatus of the container lid with packing of another example to the limit point (A position) of one end side (left end side). It is sectional drawing which showed the state which moved the shutter plate provided in the periphery of the nozzle in FIG. 8 to the intermediate position. It is sectional drawing which showed the state which moved the shutter plate provided in the periphery of the nozzle in FIG. 8 to the limit point (B position) of the other end side (right end side). It is sectional drawing to which the fitting groove periphery of the container lid in which the cross-section packing was formed was expanded. It is sectional drawing to which the fitting groove periphery of the container lid in which the packing of the cross-sectional semicircle was formed was expanded. It is sectional drawing to which the fitting groove periphery of the container lid in which the cross-section concave packing was formed was expanded. It is sectional drawing which showed a mode that several container lids were piled up and a packing with a concave cross section was formed.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Thermoplastic resin injection | throwing-in part 20 Extruder 30 Foaming agent press injection part 40-44 Nozzle 50 Container lid supply means 60 Container lid moving means 70 Nozzle base 80 Shutter plate 81-84 Hole 90 Container lid discharge means 100 Container lid 110 with packing 110 Container Lid 111 Fitting groove 120 Thermoplastic resin (packing)
121 Foaming agent

Claims (10)

With a packing that integrally forms a packing along the fitting groove by extruding the thermoplastic resin heated and melted by an extruder in a line from a nozzle and pouring it into a fitting groove provided on one side of the container lid A method for manufacturing a container lid, in which a plurality of nozzles are provided, a thermoplastic resin added with a foaming agent is heated and melted inside the extruder, and the heated and melted thermoplastic resin is combined with one set of nozzles and another set. And alternately discharging the thermoplastic resin into the fitting groove of the container lid below one set of nozzles and the fitting groove of the container lid below the other set of nozzles, Foaming immediately after discharging from the nozzle, filling the fitting groove into the fitting groove without heating the entire container lid, and making it possible to sequentially form packing for a plurality of container lids Manufacturing method of container lid with packing   The manufacturing method of the container lid with packing of Claim 1 which press-fits the foaming agent which consists of gas or a liquid with respect to the thermoplastic resin heat-melted inside the extruder.   The method for producing a container lid with packing according to claim 1 or 2, wherein the expansion ratio of the thermoplastic resin is 2 to 30 times.   The method for producing a container lid with packing according to any one of claims 1 to 3, wherein the thermoplastic resin is polyolefin.   The thermoplastic resin is discharged from a position-fixed nozzle and poured into the fitting groove while rotating the container lid provided with the fitting groove in an annular shape around the central axis of the fitting groove. 4. A method for producing a container lid with packing according to any one of 4 above.   The manufacturing method of the container lid with packing of any one of Claims 1-5 which sprays a hot air on the overlap part of the start end of the thermoplastic resin poured into the said fitting groove, and a termination | terminus, and welds this overlap part.   The hot air is blown onto the overlapping portion of the thermoplastic resin poured into the fitting groove and the overlapping portion is welded, and then the overlapping portion is pressed in the depth direction of the fitting groove. The manufacturing method of the container lid with packing of description.   A recess or a flat portion along the longitudinal direction is formed in the packing by pressing the thermoplastic resin poured into the fitting groove in the depth direction of the fitting groove with a mold along the fitting groove. The manufacturing method of the container lid with packing in any one of claim | item 1 -7.   The manufacturing method of the container lid with packing in any one of Claims 1-7 which forms the discharge port of a nozzle in non-circle, and forms the recessed part or flat part along a longitudinal direction in packing. An apparatus for manufacturing a container lid with packing that integrally forms a packing along a fitting groove by extruding a thermoplastic resin linearly from a nozzle and pouring the resin into a fitting groove provided on one surface of the container lid. A thermoplastic resin charging part for charging the thermoplastic resin, an extruder for heating and melting the thermoplastic resin, and foaming of gas or liquid to the thermoplastic resin heated and melted inside the extruder A foaming agent press-fitting part for press-fitting the agent, a nozzle for discharging the thermoplastic resin heated and melted inside the extruder to the outside of the extruder, and a container lid for supplying a container lid below the nozzle Supply means, and container lid moving means for moving the container lid below the nozzle so that the thermoplastic resin extruded from the nozzle flows along the fitting groove,
A plurality of nozzles are provided, and a thermoplastic resin to which a foaming agent is added is heated and melted inside the extruder, and the heated and melted thermoplastic resin is alternately discharged from one set of nozzles and another set of nozzles. The thermoplastic resin is alternately poured into the fitting groove of the container lid below one set of nozzles and the fitting groove of the container lid below the other set of nozzles, and foamed immediately after being discharged from the nozzles. The container lid with packing is characterized in that the filling groove is filled with the foam without heating the entire container lid, and packing can be sequentially formed for a plurality of container lids. Manufacturing equipment.

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