Molding machine

Abstract

The present invention provides a molding machine in which a servo motor can be used as a drive for an intermittent rotary drive molding device and an auxiliary device therefor, without entailing an increase in overall size.　A molding machine 1 is provided with a base 2 having a top plate 21 and a bottom plate 22, and intermittent rotary drive molding devices 3, 5, 6 installed on the base. The molding devices comprise: rotating bodies 31, 51, 61 disposed horizontally above the top plate; drives 32, 52, 62 disposed in an internal space S of the base and having drive shafts 33, 53, 63; driven shafts 33, 53, 63 of which upper parts are connected to the rotating bodies and lower parts are made to protrude through the top plate and into the internal space; and roller gear cam mechanisms 35, 55, 65 comprising roller gear cams 351, 551, 651 provided on the drive shafts and cam followers 352, 552, 652 provided on the lower parts of the driven shafts. Upwardly opening box-shaped covers 9A, 9B, 9C capable of accommodating the roller gear cam mechanisms are attached to the top plate in a suspended state.

Description

Forming machine

[0001] The present invention relates to a forming machine, and more particularly to a forming machine in which an intermittently rotatable drive type forming device is installed on a base.

[0002] For example, as a forming machine for forming a cup-shaped paper container (paper cup) from a blank made of a sheet mainly composed of paper, the one described in Patent Document 1 is known. This paper container forming machine includes a base having a top plate and a bottom plate arranged at intervals in the vertical direction so that an internal space is formed, and an intermittently rotatable drive type forming device installed on the base. The intermittently rotatable drive type forming device includes a turret horizontally arranged above the top plate, a drive machine arranged in the internal space of the base and having a drive shaft, a driven shaft having an upper part connected to the turret, penetrating the top plate, and a lower part protruding into the internal space of the base, and a roller gear cam mechanism including a roller gear cam provided on the drive shaft so as to intermittently rotate and drive the turret and a cam follower provided at the lower part of the driven shaft. A plurality of mandrels are provided on the turret at intervals in the circumferential direction. When the turret is intermittently rotationally driven, the blanks held by each mandrel are stopped at a plurality of forming stations provided around the turret for a predetermined time each, and predetermined forming processes on the blanks are sequentially performed.

[0003] Patent Document 2 describes an intermittent drive device including an index unit in which a roller gear cam mechanism is housed in a housing, and the index unit is generally commercially available.

[0004] U.S. Patent No. 5324249, Japanese Utility Model Publication No. 6-39161

[0005] In the case of the paper container molding machine described in Patent Document 1, a conventional motor is used as the drive for driving the turret, and the motor also drives multiple auxiliary devices for performing predetermined molding processes on the blank at each molding station. For this reason, the motor's drive shaft is made long, and in addition to the roller gear cam of the roller gear cam mechanism, numerous drive cams for driving the auxiliary devices are attached to this drive shaft (see FIG. 12, etc.). However, such a drive mechanism requires a large installation space in the internal space of the base, causes significant vibration of the drive shaft, and furthermore, makes it difficult to adjust the drive of the turret and auxiliary devices. Here, it is thought that if the turret and auxiliary devices are driven by servo motors, it will be possible to reduce vibration of the drive shaft and other components and to simplify the adjustment of each device. However, in the case of the conventional paper container molding machine described above, the lubricating oil supplied to the roller gear cam mechanism scatters into the internal space of the base, making it difficult to use servo motors as the drive for the turret and auxiliary devices. Furthermore, if a commercially available index unit having the configuration described in Patent Document 2 can be applied to the molding apparatus of the paper container molding machine described in Patent Document 1, the scattering of lubricating oil can be prevented. However, the housing of the index unit needs to be robust enough to withstand high loads, and is therefore large. As a result, the installation space for the index unit in the internal space of the base becomes relatively large, and there is a problem that the entire paper container molding machine becomes larger, especially when multiple index units are installed.

[0006] This invention has been made in view of the above-mentioned problems, and aims to provide a molding machine that can use a servo motor as the drive for an intermittent rotation drive type molding device or its auxiliary device without increasing the overall size.

[0007] To achieve the above objective, this invention comprises the following embodiments.

[0008] 1) A molding machine comprising a base having a top plate and a bottom plate arranged vertically apart to form an internal space, and an intermittent rotation drive type molding device installed on the base, wherein the molding device comprises a rotating body horizontally positioned above the top plate, a drive machine positioned in the internal space and having a drive shaft, a driven shaft whose upper part is connected to the rotating body and whose lower part protrudes into the internal space through the top plate, and a roller gear cam mechanism provided on the drive shaft and a cam follower provided at the lower part of the driven shaft so as to be able to intermittently rotate the rotating body, and an upward-opening box-shaped cover capable of housing the roller gear cam mechanism is attached to the top plate in a hanging manner.

[0009] 2) The molding machine according to 1), wherein the cover is connected to the bottom plate directly or via a lower connecting member.

[0010] 3) The molding machine according to 1) or 2), wherein the base has support columns connecting the top plate and the bottom plate, and the cover is connected to the support columns directly or via side connecting members.

[0011] 4) A molding machine according to any one of 1) to 3) above, wherein the top plate comprises a top plate body having an opening through which the cover can pass, and a lid member having a flange portion that is detachably attached to the peripheral edge of the opening in the top plate body, and the cover is attached to the lid member.

[0012] 5) A molding machine according to any one of 1) to 4) above, wherein a drive cam for driving an auxiliary device of the molding apparatus is provided on the drive shaft, and the drive cam is housed in the cover together with the roller gear cam mechanism.

[0013] 6) A molding machine according to any one of 1) to 5) above, wherein a plurality of the molding devices are installed in close proximity to each other on the base, the roller gear cam mechanisms of the plurality of the molding devices are individually housed in a plurality of the covers, and the plurality of the covers are connected to each other directly or via intermediate connecting members.

[0014] 7) A molding machine according to any one of 1) to 6) above, wherein the drive mechanism is a servo motor.

[0015] 8) A molding machine that forms a cup-shaped paper container from a blank made of a paper-based sheet, one of the molding machines described in 1) to 7) above.

[0016] According to the molding machine described in 1), the roller gear cam mechanism of the intermittent rotation drive type molding device is housed in a cover that is suspended from the top plate of the base, and the splashing of lubricating oil supplied to the roller gear cam mechanism is effectively prevented by the cover, so a servo motor can be used without hindrance as the drive for the molding device and its auxiliary devices, thereby reducing vibration of the drive shaft and making it easier to adjust each device. In addition, according to the molding machine described in 1), the size of the cover can be made smaller compared to the index unit, so the overall size of the molding machine can be made smaller. According to the molding machine described in 2) or 3), the cover housing the roller gear cam mechanism is supported from below or from the side, so vibration of the drive shaft and the like due to the load on the roller gear cam mechanism is effectively suppressed, so the molding process by the molding device can be performed without hindrance. In addition, according to the molding machine described in 2) or 3), the mounting strength of the cover is improved and vibration and deformation of the cover are suppressed, so it is possible to make the material constituting the cover thinner and make the cover smaller. Therefore, even when multiple intermittent rotation-driven molding devices are installed on the base, the pitch between the molding devices can be reduced to miniaturize the entire molding machine. In the molding machine described in 4), the cover housing the roller gear cam mechanism is attached to a lid member to form a unit, which is then installed on the base from above the top plate and can be removed from the base for maintenance, etc., making these operations easy. In the molding machine described in 5), the auxiliary devices of the molding device can be operated in synchronization with the intermittently rotation-driven rotating body of the molding device, and since the roller gear cam mechanism and drive cam are housed in a single cover, space can be saved, and the lubrication of the roller gear cam mechanism and drive cam can be performed together with lubricating oil. In the molding machine described in 6), when multiple intermittent rotation-driven molding devices are installed on the base, the covers housing the roller gear cam mechanisms are connected to each other, which more effectively suppresses vibrations of the drive shaft etc. due to the load on each roller gear cam mechanism, so that molding by the molding device can be performed without hindrance.Furthermore, according to the molding machine described in 6), the mounting strength of the cover is further improved, and vibration and deformation of the cover are more reliably suppressed, making it possible to make the cover smaller by making the material constituting each cover thinner, and thus reducing the pitch between molding devices and making the entire molding machine smaller. According to the molding machine described in 7), predetermined molding processes can be performed with high precision and high efficiency using an intermittent rotation drive type molding device. According to the molding machine described in 8), it can be suitably used as a molding machine for forming cup-shaped paper containers.

[0017] This is a plan view showing the overall configuration of a paper container molding machine according to an embodiment of this invention. This is a horizontal cross-sectional view showing the internal structure of the base in the paper container molding machine. This is a vertical cross-sectional view of the paper container molding machine along line A-A in Figure 2, omitting molding devices other than the body molding device. This is a perspective view showing the body molding device of the paper container molding machine. This is a front view showing the body molding device. This is a horizontal cross-sectional view of the body molding device along line B-B in Figure 5. This shows the structure for connecting the cover of the body molding device to the bottom plate, with (a) being a vertical cross-sectional view and (b) being a perspective view. This is a horizontal cross-sectional view showing the structure for connecting the covers of the three molding devices of the paper container molding machine to each other. This is a perspective view showing the structure for connecting the cover of the body molding device to the support column.

[0018] Embodiments of this invention will be described below with reference to Figures 1 to 9. In the following description, the bottom of Figures 1 and 2 will be referred to as the "front," the top of Figures 1 and 2 as the "rear," and "left and right" will refer to the left and right when viewed from the front (for example, the left and right in Figures 1 to 3).

[0019] The illustrated embodiment applies this invention to a paper container molding machine (1) that forms a cup-shaped paper container from a blank made of a paper-based sheet. The paper container molding machine (1) comprises a base (2) and a plurality of molding devices (3)(4)(5)(6) installed on the base (2).

[0020] The base (2) has a top plate (21) and a bottom plate (22) that are spaced apart vertically to form an internal space (S). The top plate (21) and the bottom plate (22) are connected by a number of support columns (23) (eight in total in the figures) (see Figures 2 and 3).

[0021] As shown in Figure 1, the molding apparatus installed on the base (2) consists of a body molding apparatus (3), a bottom molding apparatus (4), a bottom molding apparatus (5), and a top molding apparatus (6). These apparatuses (3), (4), (5), and (6) are installed on the base (2) in close proximity to each other so that a predetermined number of molding processes are performed sequentially. Of these apparatuses (3), (4), (5), and (6), the body molding apparatus (3), the bottom molding apparatus (5), and the top molding apparatus (6) are of the intermittent rotation drive type.

[0022] In the body molding apparatus (3), the process of forming the body is carried out by rolling the blank into a cylindrical shape and sealing the edges at both ends thereof. The blank is formed, for example, by punching out a roughly fan-shaped sheet of cardboard on which thermoplastic resin is laminated at least one side. The blank is supplied to the body molding apparatus (3) by a blank supply device (7) installed adjacent to the body molding apparatus (3).

[0023] In the bottom forming apparatus (4), the strip-shaped sheet supplied by the sheet supply apparatus (8) is punched out into a circular shape and then press-formed to form the bottom, which consists of a circular horizontal section and a hanging section extending downward from the outer edge of the horizontal section. Typically, the strip-shaped sheet used has the same configuration as the blank described above.

[0024] In the bottom forming device (5), the lower end of the body supplied from the body forming device (3) is folded inward to enclose the hanging portion of the bottom supplied from the bottom forming device (4), and both parts are sealed to join and integrate the body and bottom to form a paper container.

[0025] In the top molding device (6), the process of completing the paper container is performed by curling the upper end of the body of the paper container (unfinished product) supplied from the bottom molding device (5) outward to form a flange.

[0026] The body molding device (3), bottom molding device (5), and top molding device (6) each consist of a rotating body (31), (51), and (61) horizontally positioned above the top plate (21), a drive unit (32), (52), and (62) positioned in the internal space (S) of the base (2) and having a drive shaft (33), (53), and (63), respectively, with the upper part connected to the rotating body (31), (51), and (61) and penetrating the top plate (21) and the lower part in the internal space of the base (2). The system includes driven shafts (34), (54), and (64) that protrude between them (S), and a roller gear cam mechanism (35), (55), and (65) that consists of roller gear cams (351), (551), and (651) provided on the drive shafts (33), (53), and (63) so as to be able to intermittently rotate the rotating body (31), (51), and (61), and cam followers (352), (552), and (652) provided at the lower part of the driven shafts (34), (54), and (64).

[0027] The rotating body (31) of the body forming apparatus (3) consists of a turret equipped with multiple mandrels (311). The rotating bodies (51) and (61) of the bottom forming apparatus (5) and the top forming apparatus (6) each consist of a rotary table.

[0028] The drive units (32), (52), and (62) of the three intermittent rotary-driven molding machines (3), (5), and (6) each consist of servo motors, and the drive shafts (input shafts) (33), (53), and (63) are arranged to extend in a predetermined horizontal direction.

[0029] The driven shafts (output shafts) (34), (54), and (64) of the three intermittent rotary-driven molding devices (3), (5), and (6) are each mounted to the top plate (21) via bearings so as to be rotatable around a vertical axis.

[0030] Furthermore, the roller gear cam mechanisms (35), (55), and (65) of the three intermittent rotary-driven molding devices (3), (5), and (6) each consist of a roller gear cam (351), (551), and (651) provided on the drive shaft (33), (53), and (63), and a cam follower (352), (552), and (652) provided at the bottom of the driven shaft (34), (54), and (64) so ​​as to be able to contact the roller gear cam (351), (551), and (651). The three roller gear cam mechanisms (35), (55), and (65) are arranged at a narrow pitch in the internal space (S) of the base (2) to match the arrangement of the three rotating bodies (31), (51), and (61) on the top plate (21), and are miniaturized so as not to interfere with each other, and the gaps between the components are made as small as possible.

[0031] When the drive shafts (33), (53), and (63) are continuously rotated by the servo motors constituting the drive unit (32), (52), and (62), the driven shafts (34), (54), and (64) and the rotating bodies (31), (51), and (61) are intermittently driven via the roller gear cam mechanism (35), (55), and (65), and predetermined molding processes are sequentially performed on each rotating body (31), (51), and (61).

[0032] The drive shaft (33) of the body forming apparatus (3) is equipped with two drive cams (361) for driving a blank winding apparatus (36), which is an auxiliary apparatus of the apparatus (3) (see Figure 6, etc.). As shown in Figures 2 to 6, the blank winding apparatus (36) is a device for winding a blank onto a mandrel (311) and has a pair of winding wings (362) that are openable and closable. The upper ends of wing drive levers (363) are connected to each of the two winding wings (362). The two wing drive levers (363) are pivotable and form a cam follower whose lower ends are in contact with two drive cams (361). As the drive shaft (33) rotates continuously, the two wing drive levers (363) are oscillated via the two drive cams (361), causing a pair of winding wings (362) to open and close with a slight time difference. This causes the blank to be sequentially wound around the mandrel (311), which has been temporarily held at a predetermined rotational position. With the above configuration, the rotational drive of the mandrel (311) of the body forming device (3) and the opening and closing drive of the winding wings (362) of the blank winding device (36) are both performed by the rotation of a single common drive shaft (33), so they can be perfectly synchronized, and there is no risk of discrepancies or interference between their operations. Although detailed illustrations have been omitted, auxiliary devices other than the blank winding device (36), specifically the blank holding device that receives and holds the blank from the blank supply device (7), the blank pushing device that holds the blank on the outer surface of the mandrel (311), and the blank sealing device that seals the ends of the rolled-up blank together, are each driven by a servo motor separate from the servo motor that constitutes the drive unit (32) described above. The auxiliary devices for the bottom forming device (5) and the top forming device (6) are also the same as described above.

[0033] As shown in Figure 2, etc., the roller gear cam mechanisms (35), (55), and (65) of the three intermittent rotary-driven molding devices (3), (5), and (6) are housed in upward-opening box-shaped covers (9A), (9B), and (9C) that are suspended from the top plate (21). Each of the three covers (9A), (9B), and (9C) has four side walls (91) on the front, back, left, and right sides, and a bottom wall (92), and is made of a rigid plate material such as stainless steel. Furthermore, the three covers (9A), (9B), and (9C) are configured to have the smallest possible external dimensions to correspond to the three roller gear cam mechanisms (35), (55), and (65) which are arranged at a narrow pitch and have been miniaturized. For this reason, the plate material constituting the covers (9A), (9B), and (9C) is preferably made of a material with a small thickness, within the range in which the necessary strength can be obtained. Specifically, the plate thickness of the plate material constituting the covers (9A), (9B), and (9C) is preferably 16 to 24 mm, and more preferably 18 to 22 mm. Each cover (9A), (9B), and (9C) has a rectangular window portion (93) formed in one or more predetermined side walls (91), and a cover plate (94) that closes the window portion (93) is detachably attached. Maintenance work on the roller gear cam mechanism (35), (55), and (65) is performed through these windows (93). Drive shafts (33), (53), and (63) are rotatably attached to the front and rear or left and right side walls (91) of each cover (9A), (9B), and (9C) via bearings. Furthermore, servo motors constituting the drive units (32), (52), and (62) are attached to predetermined side walls (91) of each cover (9A), (9B), and (9C) via a retaining frame (14). Lubricating oil is injected into each cover (9A), (9B), and (9C). The required amount of lubricating oil is injected into each cover (9A), (9B), and (9C) to a height that immerses at least a portion of the roller gear cams (351), (551), and (651). In addition, an oil seal is provided between the drive shafts (33), (53), and (63) and the bearings to prevent the lubricating oil from leaking out of the covers (9A), (9B), and (9C). The cover (9A) of the body molding device (3) houses the two drive cams (361) mentioned above, in addition to the roller gear cam mechanism (35).In this way, by housing the roller gear cam mechanism (35) and the two drive cams (361) within a single cover (9A), space can be saved, and the lubrication of the roller gear cam mechanism (35) and the drive cams (361) can be performed collectively with lubricating oil.

[0034] In this embodiment of the paper container molding machine (1), the top plate (21) of the base (2) comprises a top plate body (21a) having three openings (211) through which three covers (9A), (9B), and (9C) can pass, and three lid members (21b) having flange portions (212) that are detachably attached to the peripheral edges of each opening (211) in the top plate body (21a). Each cover (9A), (9B), and (9C) is attached to the corresponding lid member (21b) in a hanging manner. Each opening (211) of the top plate body (21a) is composed of a rectangular hole that is slightly larger than the outer contour of each cover (9A), (9B), and (9C) as viewed from above. Each lid member (21b) is made of a rectangular rigid plate material that is slightly larger than each opening (211), and the flange portion (212) is formed by its outer peripheral edge. The flange portion (212) of each lid member (21b) is placed on the peripheral edge of each opening (211) on the upper surface of the top plate body (21a) and is detachably attached to the same portion by a plurality of bolts. Driven shafts (34), (54), and (64) are rotatably attached to each lid member (21b) via bearings. In addition, an oil seal is provided between the driven shafts (34), (54), and (64) and the bearings to prevent the lubricating oil inside the covers (9A), (9B), and (9C) from leaking out onto the upper surface of the top plate (21). According to the above configuration, in each intermittent rotary drive molding device (3),(5),(6), a unit is formed by attaching a cover (9A),(9B),(9C) containing a roller gear cam mechanism (35),(55),(65), etc., to a lid member (21b). In other words, a drive unit (see Figures 4 to 6, etc.) consisting of a servo motor drive unit (32),(52),(62), drive shafts (33),(53),(63), driven shafts (34),(54),(64), roller gear cam mechanism (35),(55),(65), etc., covers (9A),(9B),(9C), and lid member (21b) is installed on the base (2) from above the top plate (21), and can also be removed from the base (2) for maintenance, etc., making these operations easy.

[0035] As shown in Figures 3, 7, etc., each cover (9A), (9B), and (9C) is connected to the bottom plate (22) via a lower connecting member (11). In the illustrated paper container molding machine (1), the connection between each cover (9A), (9B), and (9C) and the bottom plate (22) is made using four lower connecting members (11). Each lower connecting member (11) is L-shaped in front view, comprising a horizontal bottom wall portion (111) and a vertical rising wall portion (112) extending upward from one side of the bottom wall portion (111). The bottom wall portion (111) is connected and fixed to the upper surface of the bottom plate (22) by bolts. The upper part of the rising wall portion (112) is connected and fixed to the lower part of the outer surface of the side wall portion (91) of the cover (9A), (9B), and (9C) by bolts. Although detailed illustrations are omitted, each lower connecting member (11) has a bottom wall portion (111) and a rising wall portion (112) with elongated bolt insertion holes, which can absorb slight misalignments in the placement of the covers (9A), (9B), and (9C) and connect to the bottom plate (22). As shown in the figure, each lower connecting member (11) may be provided with a vertical plate-shaped reinforcing rib (113) that spans and connects the bottom wall portion (111) and the rising wall portion (112). In addition, each lower connecting member (11) may be provided with a support projection (114) at a predetermined height position on one side of the rising wall portion (112) for supporting the bottom wall portion (92) of the covers (9A), (9B), and (9C) from below. With the above-described connection structure, the drive unit, including the covers (9A), (9B), and (9C) housing the roller gear cam mechanisms (35), (55), and (65), is supported from below. This effectively suppresses vibrations of the drive shafts (33), (53), and (63) caused by the load on the roller gear cam mechanisms (35), (55), and (65), allowing the molding process by the molding devices (3), (5), and (6) to proceed without hindrance. Furthermore, the above-described connection structure improves the mounting strength of the covers (9A), (9B), and (9C), suppressing vibrations and deformation of the covers (9A), (9B), and (9C). This makes it possible to make the covers (9A), (9B), and (9C) smaller by using thinner plate materials. As a result, the pitch between the molding devices (3), (5), and (6) installed on the base (2) can be reduced, thereby miniaturizing the entire paper container molding machine (1).Furthermore, depending on their arrangement, the covers (9A), (9B), and (9C) and the base plate (22) can be directly connected without using the lower connecting member (11), thereby further improving the mounting strength of the drive unit. However, adjusting the gap between the covers (9A), (9B), and (9C) and the base plate (22) to zero is not easy, and it is practically preferable to use the lower connecting member (11) to connect the two in order to absorb variations in this gap.

[0036] Furthermore, as shown in Figures 2 and 8, the three covers (9A), (9B), and (9C) are connected to each other via a plurality of intermediate connecting members (12). The intermediate connecting member (12) is L-shaped in plan view and comprises a vertical base wall portion (121) and a vertical lateral projection wall portion (122) extending laterally from one side of the base wall portion (121). The intermediate connecting member (12) may be provided with a horizontal plate-shaped reinforcing rib (123) that spans and is joined to connect the base wall portion (121) and the lateral projection wall portion (122). The connection between the cover (9A) of the body molding device (3) and the cover (9B) of the bottom molding device (5), and the connection between the cover (9B) of the bottom molding device (5) and the cover (9C) of the top molding device (6) are each made using one intermediate connecting member (12). The base wall portion (121) is connected and fixed to the outer surface of the side wall portion (91) of one of the covers (9A) and (9B) by bolts. The tip portion of the lateral projection wall portion (122) is connected and fixed to the outer surface of the side wall portion (91) of the other cover (9B) and (9C), perpendicular to the side wall portion (91) of the first cover (9A) and (9B), by bolts. Bolt insertion holes (not shown) consisting of elongated holes are formed in the tip portions of the base wall portion (121) and lateral projection wall portion (122) of each intermediate connecting member (12), allowing them to be connected to each other while absorbing slight misalignments in the arrangement of the covers (9A) and (9B) and (9C). Furthermore, the connection between the cover (9A) of the body molding device (3) and the cover (9C) of the top molding device (6) is made using two intermediate connecting members (12) connected in series. The two intermediate connecting members (12) are integrated by connecting the tip portions of their lateral protruding wall portions (122) with bolts. Then, the base wall portion (121) of one intermediate connecting member (12) is connected and fixed with bolts to the outer surface of one of the opposing side wall portions (91) of both covers (9A) and (9C), and the base wall portion (121) of the other intermediate connecting member (12) is connected and fixed with bolts to the outer surface of the other side wall portion (91).According to the above-described connecting structure, vibrations of the drive shafts (33), (53), and (63) during operation, as well as vibrations and deformations of the covers (9A), (9B), and (9C), are more effectively suppressed in each intermittently rotary-driven molding device (3), (5), and (6). Furthermore, depending on their arrangement, the covers (9A), (9B), and (9C) can be directly connected to each other without the intermediate connecting member (12), thereby further improving the mounting strength of the covers (9A), (9B), and (9C) and the unit including them. However, adjusting the gap between the covers (9A), (9B), and (9C) to zero is not easy, and it is practically preferable to use the intermediate connecting member (12) to connect them in order to absorb variations in this gap.

[0037] Furthermore, as shown in Figures 2 and 9, the three covers (9A), (9B), and (9C) are connected to adjacent support columns (23) via side connecting members (13). In the illustrated paper container molding machine (1), the support columns (23) are located at the midpoints of the lengths of the four corners and four sides of the base (2). Each support column (23) is made of a shaped material such as channel steel. The three covers (9A), (9B), and (9C) are respectively connected to the support columns (23) erected at the midpoints of the lengths of the front, rear, and left sides of the base (2). The side connecting member (13) has a similar configuration to the intermediate connecting member (12) and is L-shaped in plan view, comprising a vertical base wall portion (131) and a vertical lateral projection wall portion (132) extending laterally from one side of the base wall portion (131). The side connecting member (13) may be provided with a horizontal plate-shaped reinforcing rib (133) that spans and connects the base wall portion (131) and the lateral projection wall portion (132). The base wall portion (131) is connected and fixed to the outer surface of the side wall portion (91) of the cover (9A)(9B)(9C) by bolts. The tip portion of the lateral projection wall portion (132) is connected and fixed to the outer surface of one side wall portion of a support column (23), which is made of channel steel, for example, by bolts. Bolt insertion holes (not shown) made of elongated holes are formed in the tip portions of the base wall portion (131) and the lateral projection wall portion (132) of each side connecting member (13), so that they can be connected to each other while absorbing slight misalignments in the arrangement of the cover (9A)(9B)(9C) and the support column (23). According to the above-described connecting structure, vibrations of the drive shafts (33), (53), and (63) during operation, as well as vibrations and deformations of the covers (9A), (9B), and (9C), are more effectively suppressed in each intermittently rotary-driven molding device (3), (5), and (6). Depending on their arrangement, the covers (9A), (9B), and (9C) and the support columns (23) can also be directly connected without using the side connecting members (13), thereby further improving the mounting strength of the above-described unit. However, it is not easy to adjust the gap between the covers (9A), (9B), and (9C) and the support columns (23) to zero, and it is practically preferable to connect them using the side connecting members (13) to absorb variations in this gap.Furthermore, the connection between the covers (9A), (9B), and (9C) and the support columns (23) may be omitted if the support columns (23) are not located near the covers (9A), (9B), and (9C), or if connection is difficult due to the layout of the internal space (S) of the base (2).

[0038] This invention is suitably used in a molding machine in which an intermittent rotary-driven molding device is installed on a base, and in particular in a molding machine in which multiple intermittent rotary-driven molding devices are installed on a base.

[0039] (1): Paper container molding machine (molding machine) (2): Base (21): Top plate (21a): Top plate body (211): Opening (21b): Lid member (212): Flange part (22): Bottom plate (23): Support column (S): Internal space of the base (3): Body molding device (intermittent rotation drive type molding device) (31): Rotating body (32): Drive unit (servo motor) (33): Drive shaft (34): Driven shaft (35): Roller gear cam mechanism (351): Roller gear cam (352): Cam follower (36): Blank winding device (auxiliary device) (361): Drive cam (5): Bottom molding device (intermittent rotation drive type molding device) (51): Rotating body (52): Drive unit (servo motor) (53): Drive shaft (54): Driven shaft (55): Roller gear cam mechanism (551): Roller gear cam (552): Cam follower (6): Top molding machine (intermittent rotation drive type molding machine) (61): Rotating body (62): Drive unit (servo motor) (63): Drive shaft (64): Driven shaft (65): Roller gear cam mechanism (651): Roller gear cam (652): Cam follower (9A)(9B)(9C): Cover (11): Lower connecting member (12): Intermediate connecting member (13): Side connecting member

Claims

1. A molding machine comprising a base having a top plate and a bottom plate arranged vertically apart to form an internal space, and an intermittent rotation drive type molding device installed on the base, wherein the molding device comprises a rotating body horizontally positioned above the top plate, a drive machine positioned in the internal space and having a drive shaft, a driven shaft whose upper part is connected to the rotating body and whose lower part protrudes into the internal space through the top plate, and a roller gear cam mechanism provided on the drive shaft and a cam follower provided at the lower part of the driven shaft so as to be able to intermittently rotate the rotating body, and an upward-opening box-shaped cover capable of housing the roller gear cam mechanism is attached to the top plate in a hanging manner.

2. The molding machine according to claim 1, wherein the cover is connected to the bottom plate directly or via a lower connecting member.

3. The molding machine according to claim 1, wherein the base has support columns connecting the top plate and the bottom plate, and the cover is connected to the support columns directly or via side connecting members.

4. The molding machine according to claim 1, wherein the top plate comprises a top plate body having an opening through which the cover can pass, and a lid member having a flange portion that is detachably attached to the peripheral edge of the opening in the top plate body, and the cover is attached to the lid member.

5. The molding machine according to claim 1, wherein a drive cam for driving an auxiliary device of the molding machine is provided on the drive shaft, and the drive cam is housed in the cover together with the roller gear cam mechanism.

6. The molding machine according to claim 1, wherein a plurality of the molding devices are installed in close proximity to each other on the base, the roller gear cam mechanisms of the plurality of the molding devices are individually housed in a plurality of the covers, and the plurality of the covers are connected to each other directly or via intermediate connecting members.

7. The molding machine according to claim 1, wherein the drive mechanism is a servo motor.

8. The molding machine according to claim 1, which forms a cup-shaped paper container from a blank made of a sheet mainly composed of paper.

Images