Linkage mechanism, linkage device, and stretching machine

Abstract

The link mechanism 11 has a pair of rail supports 24. Each rail support 24 has guide rollers 51a, 51b, 52a, 52b that move along the rails 13, 14 while rotating on one side, roller shafts 54, 55 that are inserted into the guide rollers 51a, 51b, 52a, 52b, bearings 56a, 56b, 57a, 57b that are sandwiched between the guide rollers 51a, 51b, 52a, 52b and the roller shafts 54, 55 to rotatably support the guide rollers 51a, 51b, 52a, 52b, and lower and upper cover members 71, 72 that are respectively provided on both axial end sides of the guide rollers 51a, 51b, 52a, 52b to cover the bearings 56a, 56b, 57a, 57b.

Description

Technical Field

[0001] This invention relates to linkage mechanisms, linkage devices, and tensioning machines. Background Technology

[0002] Stretching machines are known for simultaneously stretching sheets, films, and other membranes in both longitudinal and transverse directions while transporting them. For example, Patent Document 1 (Patent No. 4379306) discloses a biaxial stretching machine that performs both longitudinal and transverse stretching of a sheet at the same time. The biaxial stretching machine disclosed in Patent Document 1 includes an annular connecting rod device, which has an equal-length connecting rod device formed in a zigzag shape.

[0003] The equal-length connecting rod device disclosed in Patent Document 1 is rotatably supported by bearings and has multiple rollers that move while rolling on a track.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent No. 4379306 Summary of the Invention

[0007] The problem that the invention aims to solve

[0008] To extend the maintenance intervals or reduce the maintenance frequency of the stretching machine, it is desirable to extend the life of the bearings used in the stretching machine.

[0009] Other topics and new features can be found in the description and accompanying drawings of this specification.

[0010] Methods for solving problems

[0011] According to one embodiment, a linkage mechanism constitutes a linkage device used in a stretching machine for performing membrane stretching. The linkage mechanism includes: a guide roller open at both axial ends, which moves along a track while rotating; a shaft inserted through the guide roller; and a bearing sandwiched between the guide roller and the shaft, rotatably supporting the guide roller, wherein at least one of the axial ends of the guide roller is provided with a cover member covering the bearing.

[0012] The effects of the invention

[0013] According to one embodiment, the life of bearings used in a stretching machine can be extended. Attached Figure Description

[0014] Figure 1 This is a schematic diagram illustrating the configuration of a thin film manufacturing system in one embodiment.

[0015] Figure 2 It is shown Figure 1A top view showing the structure of the thin film manufacturing system.

[0016] Figure 3 It is shown Figure 1 Another top view of the structure of the thin film manufacturing system shown.

[0017] Figure 4A It is shown schematically. Figure 3 The top view of the linkage mechanism and track shown.

[0018] Figure 4B It is shown schematically. Figure 3 Another top view of the linkage mechanism and track shown.

[0019] Figure 5 It is Figure 3 An enlarged perspective view of one of the multiple linkage mechanisms shown.

[0020] Figure 6 yes Figure 5 The shown is a cross-sectional view of the linkage mechanism.

[0021] Figure 7 It is shown Figure 6 A partially enlarged cross-sectional view of the guide roller and its surrounding structure.

[0022] Figure 8 It is shown Figure 6 An exploded perspective view of the guide roller and its surrounding structure. Detailed Implementation

[0023] Hereinafter, embodiments will be described in detail based on the accompanying drawings. It should be noted that in all the drawings used to describe the embodiments, components having the same or substantially the same function are labeled with the same reference numerals and their repeated descriptions are omitted.

[0024] <The Composition of Manufacturing Systems>

[0025] Figure 1 This is a schematic diagram showing the configuration of a film manufacturing system including a stretching machine. Figure 1 The film manufacturing system 1 shown has an extrusion device (extruder, compounding extruder) 2, a T-die 3, a material roll cooling device 4, a stretching machine 5, a traction device 6, and a winding device 7.

[0026] In the film manufacturing system 1, a film is manufactured by the following process. First, raw material is supplied to the raw material supply section (raw material inlet, hopper) 2a of the extrusion unit 2. The raw material supplied to the extrusion unit 2 consists of resin material (e.g., granular thermoplastic resin material), additives, etc. The raw material supplied to the extrusion unit 2 is conveyed (transported) while being mixed. Specifically, within the extrusion unit 2, the raw material supplied to the extrusion unit 2 is melted and mixed while being conveyed forward by the rotation of the screw. The raw material (mixture) obtained by mixing in the extrusion unit 2 is supplied to the T-die 3. The mixture supplied to the T-die 3 is extruded from the slit of the T-die 3 toward the material roll cooling device 4. The mixture supplied from the extrusion unit 2 to the T-die 3 is formed into a predetermined shape (here, a film) by the T-die 3.

[0027] The compound extruded from T-die 3 is cooled in material roll cooling device 4 to form film 8. Film 8 is a cured (solid) resin film. More specifically, film 8 is a thermoplastic resin film. Film 8 is continuously extruded from T-die 3. As a result, film 8 is continuously fed to stretching machine 5.

[0028] The film 8 supplied to the stretching machine 5 is stretched by the stretching machine 5 in the MD and TD directions. After being stretched (extended) by the stretching machine 5, the film 8 is transported to the winding device 7 by the traction device 6 and wound on the winding device 7. The film 8 wound on the winding device 7 is cut as needed.

[0029] Figure 1 The thin film manufacturing system 1 shown manufactures a thin film using the process described above. However, the thin film manufacturing system 1 can be modified in various ways to accommodate the properties of the manufactured thin film. For example, there are also... Figure 1 The traction device 6 shown is provided with an extraction groove to remove plasticizers (such as paraffin wax) contained in the membrane 8.

[0030] The stretching machine 5, constituting the thin film manufacturing system 1, transports the film 8 along the MD direction while stretching it in both the MD and TD directions. In other words, the MD (Machine Direction) direction is the transport direction of the film 8. The TD (Transverse Direction) direction is the direction that intersects the transport direction of the film 8. Therefore, in the following description, the MD direction may be referred to as the "transport direction" or "longitudinal direction," and the TD direction may be referred to as the "transverse direction." The MD direction (transport direction, longitudinal direction) is a direction that intersects with the TD direction (transverse direction), or more specifically, a direction that is orthogonal to each other. That is to say, Figure 1 The stretching machine 5 shown is a stretching machine that can simultaneously stretch the membrane 8 in two intersecting directions while transporting it, and is usually called a "simultaneous biaxial stretching machine".

[0031] <Stretching machine>

[0032] Next, we will describe the stretching machine 5 in more detail. Figure 2 , Figure 3 This is a top view schematically illustrating the structure of the stretching machine 5. The stretching machine 5 has a pair of connecting rod devices 10. The pair of connecting rod devices 10 are separated from each other when viewed from above. In the following description, one of the pair of connecting rod devices 10 may be referred to as "connecting rod device 10R" and the other as "connecting rod device 10L". However, this distinction is merely for ease of explanation.

[0033] exist Figure 2 , Figure 3 In this configuration, the linkage 10R is positioned on the right (R side) relative to the transport direction (MD direction), and the linkage 10L is positioned on the left (L side) relative to the transport direction (MD direction). The linkage 10R and linkage 10L are separated in the TD direction, sandwiching the membrane 8 and facing each other in the TD direction. The membrane 8 is transported in the MD direction within the space between the linkage 10R and linkage 10L. In other words, the space between the opposing linkage 10R and linkage 10L functions as a transport section for transporting the membrane 8.

[0034] Reference Figure 3 The stretching machine 5 is divided into three zones 20A, 20B, and 20C along the transport direction (MD direction). Zone 20A is the preheating zone, zone 20B is the stretching zone, and zone 20C is the heat-setting zone. Zones 20A, 20B, and 20C are arranged sequentially along the transport direction (MD direction).

[0035] The inlet of membrane 8 in stretching machine 5 ( Figure 2 , Figure 3 The portion indicated by "IN" is located in region 20A. Additionally, the outlet of membrane 8 in stretching machine 5 ( Figure 2 , Figure 3 The portion marked "OUT" is located in region 20C. Furthermore, there is a stretching process region 20B between region 20A, where the inlet of membrane 8 is located, and region 20C, where the outlet of membrane 8 is located.

[0036] The heat treatment section 9 covers a portion of region 20A, the entirety of region 20B, and a portion of region 20C. Furthermore, the heat treatment section 9 covers the central portion of the connecting rod devices 10R and 10L, and heats the film 8 transported by the connecting rod devices 10R and 10L. In this embodiment, the heat treatment section 9 is formed in an oven capable of heating the film 8 to a desired temperature. The film 8 passes through the oven, which serves as the heat treatment section 9, while being held by the connecting rod devices 10R and 10L.

[0037] <Linkage Device>

[0038] like Figure 2 , Figure 3 As shown, each of the linkage devices 10R and 10L has multiple linkage mechanisms 11 connected in a circular chain configuration, and each linkage mechanism 11 has a clamp 21 serving as a gripper for holding the membrane 8. The membrane 8 is held by the clamps 21 provided by the linkage mechanism 11 constituting the linkage device 10R and the linkage mechanism 11 constituting the linkage device 10L. That is, one side (R side / right side) of the membrane 8 is held by the multiple clamps 21 provided by the linkage device 10R, and the other side (L side / left side) of the membrane 8 is held by the multiple clamps 21 provided by the linkage device 10L.

[0039] In addition to multiple linkage mechanisms 11, each linkage device 10R and 10L has a pair of tracks 13 and 14 disposed on a support platform (base). In each linkage device 10R and 10L, track 13 is disposed on the inner circumference side, and track 14 is disposed on the outer circumference side. Therefore, track 13 may be referred to as the "inner track" and track 14 as the "outer track". Furthermore, track 13 may also be referred to as the "reference track" or "SP track", and track 14 as the "MD track".

[0040] Each linkage device 10R and 10L has tracks 13 and 14 arranged in a ring within regions 20A, 20B, and 20C. More specifically, tracks 13 and 14 turn back in region 20A where the membrane 8 is located, and turn back in region 20C where the membrane 8 is located, and are arranged in a ring within regions 20A, 20B, and 20C.

[0041] Three sprockets 15, 16, and 17 are provided inside the track 13 of the linkage 10R. Similarly, three sprockets 15, 16, and 17 are provided inside the track 13 of the linkage 10L. Sprockets 15 and 16 in each linkage 10R and 10L are located in region A, and sprocket 17 in each linkage 10R and 10L is located in region C. However, sprockets 15 and 16 are located outside the heat treatment section 9, which covers a portion of region A. Additionally, sprocket 17 is located outside the heat treatment section 9, which covers a portion of region C. In other words, sprockets 15, 16, and 17 of each linkage 10R and 10L are located outside the oven, which serves as the heat treatment section 9.

[0042] The linkage devices 10R and 10L have multiple linkage mechanisms 11 arranged on the tracks 13 and 14 in a state that allows them to move along the tracks 13 and 14. Figure 3The sprockets 15, 16, and 17 of the linkage 10R shown engage with the multiple linkage mechanisms 11 of the linkage 10R. Thus, when the sprockets 15, 16, and 17 rotate, the driving force acts on the multiple linkage mechanisms 11 of the linkage 10R, and these linkage mechanisms 11 move (travel) along the tracks 13 and 14 of the linkage 10R. Figure 3 The sprockets 15, 16, and 17 of the linkage 10L shown engage with the multiple linkage mechanisms 11 of the linkage 10L. Thus, when the sprockets 15, 16, and 17 rotate, a driving force is applied to the multiple linkage mechanisms 11 of the linkage 10L, causing these linkage mechanisms 11 to move (travel) along the tracks 13 and 14 of the linkage 10L. In other words, the tracks 13 and 14 of each linkage 10R and 10L are guide rails for moving (traveling) the multiple linkage mechanisms 11 in a predetermined direction.

[0043] In the following explanation, for Figure 3 The linkage devices 10R and 10L shown in the diagram have a configuration where the side opposite to the membrane 8 is called the "membrane side" and the side opposite to the membrane side is called the "return side". That is, when the clamp 21 holds the membrane 8, the side on which the multiple linkage mechanisms 11 move from the inlet (IN) towards the outlet (OUT) is the membrane side, and the side on the opposite side of the membrane side, where the multiple linkage mechanisms 11 move from the outlet (OUT) towards the inlet (IN) when the clamp 21 does not hold the membrane 8, is the return side.

[0044] The spacing between adjacent linkages 11 (also referred to as "linkage spacing") varies corresponding to the spacing (separation distance) between rails 13 and 14. In other words, the spacing between adjacent linkages 11 can be adjusted by adjusting the separation distance between rails 13 and 14.

[0045] Figure 4A , Figure 4B It is shown schematically. Figure 3 A top view of the linkage mechanism and track shown. Figure 4A , Figure 4B As shown, the smaller the separation distance L1 between tracks 13 and 14, the larger the angle between adjacent linkages 11, and the larger the interval P1 between adjacent linkages 11. On the other hand, the larger the separation distance L1 between tracks 13 and 14, the smaller the angle between adjacent linkages 11, and the smaller the interval P1 between adjacent linkages 11.

[0046] As previously described, each linkage 11 has a clamp 21 that holds the diaphragm 8. Therefore, the distance P2 between adjacent clamps 21 increases or decreases corresponding to the increase or decrease of the distance P1 between adjacent linkages 11. Specifically, if the separation distance L1 of tracks 13 and 14 decreases, the distance P1 between linkages 11 increases; if the distance P1 between linkages 11 increases, the distance P2 between clamps 21 also increases. Figure 4A → Figure 4B On the other hand, if the separation distance L1 between tracks 13 and 14 increases, the interval P1 between linkages 11 decreases; if the interval P1 between linkages 11 decreases, the interval P2 between clamps 21 also decreases. Figure 4B → Figure 4A ).

[0047] It should be noted that, since each of the multiple linkage mechanisms 11 has a clamp 21, the interval P1 between two adjacent linkage mechanisms 11 is the same as the interval P2 between two clamps 21 of these linkage mechanisms 11. That is, in Figure 4A , Figure 4B In both cases, P1 = P2 holds true.

[0048] <Operation of the stretching machine (simultaneous biaxial stretching machine)>

[0049] The film 8 supplied from the material roll cooling device 4 to the stretching machine 5 is held at the inlet of the stretching machine 5 by connecting rod devices 10R and 10L. Specifically, the film 8 is... Figure 2 , Figure 3 The linkage mechanism 11 of the linkage devices 10R and 10L shown is equipped with a clamp 21. More specifically, one side of the membrane 8 in the width direction is held by the clamp 21 of the linkage mechanism 11 of the linkage device 10R, and the other side of the membrane 8 in the width direction is held by the clamp 21 of the linkage mechanism 11 of the linkage device 10L.

[0050] The membrane 8, held by clamps 21 on both sides in the width direction, is transported from the inlet to the outlet of the stretching machine 5 along with the movement of the linkage mechanism 11 including the clamps 21, passing sequentially through region 20A (preheating region), region 20B (stretching region), and region 20C (heat-setting region). During its passage through region 20B (stretching region), the membrane 8 is stretched in both the MD and TD directions. Then, the membrane 8 passes through region 20C (heat-setting region) to reach the outlet and is removed from the clamps 21. The membrane 8 removed from the clamps 21 is transported by the traction device 6 and then transferred from the traction device 6 to the winding device 7.

[0051] like Figure 3As shown, in region 20A (preheating region), the interval (separation distance in the TD direction) L2 between the tracks 13, 14 of the linkage device 10R and the tracks 13, 14 of the linkage device 10L is approximately constant. Therefore, in region 20A, no stretching treatment is performed on the membrane 8 in the TD direction. Therefore, in region 20A, the width (dimension in the TD direction) of the transported membrane 8 remains constant.

[0052] Furthermore, in region 20A, the interval (separation distance) L1 between the tracks 13 and 14 on the membrane side of the linkage device 10R is approximately constant. Therefore, in region 20A, the interval P1 of the linkage mechanism 11 on the membrane side of the linkage device 10R is approximately constant, and therefore, the interval P2 of the clamps 21 on the membrane side of the linkage device 10R is also approximately constant. Similarly, in region 20A, the interval (separation distance) L1 between the tracks 13 and 14 on the membrane side of the linkage device 10L is approximately constant. Therefore, in region 20A, the interval P1 of the linkage mechanism 11 on the membrane side of the linkage device 10L is approximately constant, and therefore, the interval P2 of the clamps 21 on the membrane side of the linkage device 10L is also approximately constant. As a result, in region 20A, no stretching process is performed on the membrane 8 in the MD direction. That is, in region 20A, no stretching process is performed on the membrane 8 in either the TD or MD directions.

[0053] Next, the operation of the stretching machine 5 in region 20B will be explained. In region 20B, as the membrane travels in the transport direction (MD direction), the gap (gap in the TD direction) between the tracks 13, 14 of the linkage device 10R and the tracks 13, 14 of the linkage device 10L gradually increases. Therefore, in region 20B, the membrane 8 is pulled and stretched in the TD direction as it travels in the transport direction (MD direction). In other words, in region 20B, the width of the membrane 8 (dimension in the TD direction) gradually increases as it travels in the transport direction (MD direction).

[0054] Furthermore, in region 20B, as the device moves in the transport direction (MD direction), the gap (separation distance) L1 between the tracks 13 and 14 on the membrane side of the linkage device 10R gradually decreases. Similarly, the gap (separation distance) L1 between the tracks 13 and 14 on the membrane side of the linkage device 10L also gradually decreases. Therefore, in region 20B, as the device moves in the transport direction (MD direction), the gap P1 of the linkage mechanisms 11 on the membrane side of the linkage device 10R gradually increases, and the gap P2 of the clamps 21 on the membrane side of the linkage device 10R also gradually increases. Furthermore, in region 20B, as the device moves in the transport direction (MD direction), the gap P1 of the linkage mechanisms 11 on the membrane side of the linkage device 10L gradually increases, and the gap P2 of the clamps 21 on the membrane side of the linkage device 10R also gradually increases. As a result, in region 20B, as the device moves in the transport direction (MD direction), the membrane 8 is pulled and stretched in the MD direction.

[0055] Therefore, in region 20B, as the membrane 8 travels in the transport direction (MD direction), it is stretched (extended) in both the TD and MD directions. That is, in region 20B, stretching treatment in both the TD and MD directions is performed on the membrane 8.

[0056] Next, the operation of the stretching machine 5 in region 20C will be explained. In region 20C, the interval (interval in the TD direction) between the tracks 13, 14 of the linkage device 10R and the tracks 13, 14 of the linkage device 10L is approximately constant. Therefore, in region 20C, stretching treatment in the TD direction for the membrane 8 is not performed. Therefore, in region 20C, the width (dimension in the TD direction) of the transported membrane 8 remains constant.

[0057] Furthermore, in region 20C, the interval (separation distance) L1 between the tracks 13 and 14 on the membrane side of the linkage device 10R is approximately constant. Therefore, in region 20C, the interval P1 of the linkage mechanism 11 on the membrane side of the linkage device 10R is approximately constant, and therefore, the interval P2 of the clamps 21 on the membrane side of the linkage device 10R is also approximately constant. Similarly, in region 20C, the interval (separation distance) L1 between the tracks 13 and 14 on the membrane side of the linkage device 10L is approximately constant. Therefore, in region 20C, the interval P1 of the linkage mechanism 11 on the membrane side of the linkage device 10L is approximately constant, and therefore, the interval P2 of the clamps 21 on the membrane side of the linkage device 10L is also approximately constant. As a result, in region 20C, no stretching treatment is performed on the membrane 8 in the MD direction. That is, in region 20C, no stretching treatment is performed on the membrane 8 in either the TD or MD directions.

[0058] As described above, in region 20A, the spacing P1 of the linkage mechanisms 11 on the membrane side of linkage device 10R remains constant, and the spacing P1 of the linkage mechanisms 11 on the membrane side of linkage device 10L also remains constant. Then, in region 20B, the spacing P1 of the linkage mechanisms 11 on the membrane side of linkage device 10R and the spacing P1 of the linkage mechanisms 11 on the membrane side of linkage device 10L gradually increases. Then, in region 20C, the spacing P1 of the linkage mechanisms 11 on the membrane side of linkage device 10R again remains constant, and the spacing P1 of the linkage mechanisms 11 on the membrane side of linkage device 10L also remains constant. Therefore, on the membrane side of each linkage device 10R and 10L, the spacing P1 of the linkage mechanisms 11 in region 20C is greater than the spacing P1 of the linkage mechanisms 11 in region 20A. From another perspective, on the membrane side of each of the connecting rod devices 10R and 10L, the spacing P2 of the clamps 21 in region 20C is greater than the spacing P2 of the clamps 21 in region 20A. From yet another perspective, on the membrane side of each of the connecting rod devices 10R and 10L, the separation distance L1 of the tracks 13 and 14 in region 20C is less than the separation distance L1 of the tracks 13 and 14 in region 20A.

[0059] <The Structure of Linkage Mechanisms>

[0060] Figure 5 It is Figure 3 An enlarged perspective view of one of the multiple linkage mechanisms shown. Figure 6 yes Figure 5 The shown is a cross-sectional view of the linkage mechanism.

[0061] like Figure 5 , Figure 6 As shown, the linkage devices 10R and 10L each have a linkage mechanism 11, in addition to the clamp 21, an upper side link plate 22, a lower side link plate 23, a pair of track supports 24a and 24b, and a base component 25 spanning the pair of track supports 24a and 24b. One track support 24a is mounted on track 14, and the other track support 24b is mounted on track 13.

[0062] The upper side link plate 22 and the lower side link plate 23 are plate-shaped components that extend in a straight line when viewed from above. The base component 25 shares the same straight-line extension as the upper side link plate 22 and the lower side link plate 23 when viewed from above, but its thickness is greater than that of the aforementioned link plates. It should be noted that in the following description, unless a special distinction is made between the track supports 24a and 24b, both will be collectively referred to as "track support 24".

[0063] <Rail support>

[0064] The track support 24a has a roller holding portion 31a and a shaft 32a disposed at the center of the roller holding portion 31a along its length. The roller holding portion 31a is disposed on the track 14 in a manner that traverses the track 14. Thus, one end of the roller holding portion 31a disposed on the track 14 protrudes to the inside of the track 14 (opposite to the track 13) along its length, and the other end of the roller holding portion 31a protrudes to the outside of the track 14 (opposite to the track 13). Furthermore, when the roller holding portion 31a is disposed on the track 14, the shaft 32a is located directly above the track 14.

[0065] like Figure 6 As shown, the shaft 32a of the track support 24a passes through one end of the upper side chain link plate 22, the lower side chain link plate 23, and the base component 25 along its length. A column ring 33 covers the upper part of the shaft 32a, which passes through the base component 25 and protrudes from it. Annular engaging portions 33a and 33b are integrally formed on both axial sides of the column ring 33. The lower insertion portion of the column ring 33, located axially outside the engaging portion 33b, is inserted into a through hole located at one end (base end) of the lower side chain link plate 23 along its length, and the engaging portion 33b overlaps the periphery of the through hole in the lower side chain link plate 23. Furthermore, the upper insertion portion of the pin ring 33, located axially outside the engaging portion 33a, is inserted into a through hole at one end (base end) of the upper side link plate 22 along its length, with the periphery of the through hole of the upper side link plate 22 overlapping the engaging portion 33a. From another perspective, the base end of the base component 25, the base end of the upper side link plate 22, and the base end of the lower side link plate 23 are connected to the shaft 32a, and are rotatably connected to each other via the shaft 32a. In other words, the shaft 32a is the rotation axis of the upper side link plate 22, the lower side link plate 23, and the base end of the base component 25.

[0066] The track support 24b has a roller holding portion 31b and a shaft 32b disposed at the center of the roller holding portion 31b in the longitudinal direction. The roller holding portion 31b is disposed on the track 13 in a manner that traverses the track 13. Thus, one end of the roller holding portion 31b disposed on the track 13 protrudes to the inside of the track 13 (the side opposite to the track 14) in the longitudinal direction, and the other end of the roller holding portion 31b protrudes to the outside of the track 13 (the side opposite to the side opposite to the track 14). In addition, when the roller holding portion 31b is disposed on the track 13, the shaft 32b is located directly above the track 13.

[0067] The shaft 32b of the track support 24b passes through one end (front end) of the base component 25 along its length and protrudes from the base component 25. By means of a column ring 34, identical to the column ring 33, one end (front end) along the length of the upper side chain plate 22 and the lower side chain plate 23 of the adjacent linkage mechanism 11 is rotatably connected to the upper part of the shaft 32b protruding from the base component 25. That is, the front end of the base component 25 of the linkage mechanism 11, and the front ends of the upper side chain plate 22 and the lower side chain plate 23 of the adjacent linkage mechanism 11 are rotatably connected to each other by means of the shaft 32b of the linkage mechanism 11. From another perspective, the shaft 32b is the rotation axis of the upper side chain plate 22, the lower side chain plate 23, and the front end of the base component 25.

[0068] <Clip>

[0069] A clip 21 is provided at the base end of the base member 25. The clip 21 has a main body 41, a gripping part 42, a spring part 43, etc. The main body 41 is fixed to the base end of the base member 25. The gripping part 42 is mounted on the main body 41 and can move up and down. The spring part 43 applies force to the gripping part 42 in a downward movement. Due to the force applied by the spring part 43, the gripping part 42 moves downward, thereby clamping the membrane 8 between the main body 41 and the gripping part 42. That is, the membrane 8 is held by the clip 21. On the other hand, if the gripping part 42 moves upward against the force applied by the spring part 43, the holding of the membrane 8 is released.

[0070] <Guide Roller>

[0071] A pair of guide rollers 51a and 51b, facing each other and sandwiching the track 14, are provided at the lower part of the track bracket 24a, and a pair of guide rollers 52a and 52b, facing each other and sandwiching the track 13, are provided at the lower part of the track bracket 24b. The guide rollers 51a, 51b, 52a, and 52b are made of metal. Each guide roller 51a, 51b, 52a, and 52b has a cylindrical shape with openings at both ends in the axial direction, and a flange 53 protruding radially outward is integrally formed on one end side (upper part) in the axial direction.

[0072] The flanges 53 of guide rollers 51a and 51b, which are provided at the lower part of track bracket 24a, are disposed on track 14, and the flanges 53 of guide rollers 52a and 52b, which are provided at the lower part of track bracket 24b, are disposed on track 13. More specifically, the flange 53 of guide roller 51a overlaps with the outer edge of the upper surface of track 14 (the side opposite to the side opposite to track 13), and the flange 53 of guide roller 51b overlaps with the inner edge of the upper surface of track 14 (the side opposite to track 13). Similarly, the flange 53 of guide roller 52a overlaps with the outer edge of the upper surface of track 13 (the side opposite to the side opposite to track 14), and the flange 53 of guide roller 52b overlaps with the inner edge of the upper surface of track 13 (the side opposite to track 14). Thus, the linkage mechanism 11 as a whole is supported by tracks 13 and 14 by means of the guide rollers 51a and 51b of track bracket 24a and the guide rollers 52a and 52b of track bracket 24b.

[0073] In other words, guide rollers 51a, 51b, 52a, and 52b are support rollers supporting the linkage mechanism 11. More specifically, guide rollers 51a, 51b, 52a, and 52b are cantilever support rollers of the linkage mechanism 11, supported by flanges 53 disposed on one axial end (upper part). From another perspective, guide rollers 51a, 51b, 52a, and 52b are flanged rollers with integrally formed flanges 53.

[0074] The four guide rollers 51a, 51b, 52a, and 52b share the same shape, structure, and dimensions. Therefore, by further describing in detail the shape and structure of the guide rollers 51a and 51b installed on the track support 24a, the shape and structure of the guide rollers 52a and 52b installed on the track support 24b are also clarified.

[0075] like Figure 6 As shown, the roller holding part 31a of the track bracket 24a is mounted on the lower end of the shaft 32a, which protrudes below the base member 25, in a state that allows it to rotate about the shaft 32a. Specifically, the roller holding part 31a is mounted on the lower end of the shaft 32a by means of a bearing.

[0076] Figure 7 It is shown Figure 6 A partially enlarged cross-sectional view of the structure of the guide rollers 51a, 51b and their surroundings. Figure 8 It is shown Figure 6 An exploded perspective view of the structure of the guide rollers 51a, 51b and their surroundings.

[0077] like Figure 7As shown, a shaft (roller shaft 54) is provided at one end of the roller holding portion 31a that protrudes to the outside of the track 14, and another shaft (roller shaft 55) is provided at the other end of the roller holding portion 31a that protrudes to the inside of the track 14. The upper part of the roller shaft 54 ​​is pressed into a mounting hole provided at one end of the roller holding portion 31a, and the upper part of the roller shaft 55 is pressed into a mounting hole provided at the other end of the roller holding portion 31a.

[0078] <Bearings>

[0079] Guide roller 51a is rotatably mounted on the lower part of roller shaft 54, which protrudes downward from roller holding portion 31a. Guide roller 51b is rotatably mounted on the lower part of roller shaft 55, which also protrudes downward from roller holding portion 31a. Specifically, the lower part of roller shaft 54 ​​passes through guide roller 51a, and bearings 56a and 56b are sandwiched between guide roller 51a and the lower part of roller shaft 54. Similarly, the lower part of roller shaft 55 passes through guide roller 51b, and bearings 57a and 57b are sandwiched between guide roller 51b and the lower part of roller shaft 55. In other words, guide roller 51a is rotatably supported relative to roller shaft 54 ​​by two bearings 56a and 56b. Furthermore, guide roller 51b is rotatably supported relative to roller shaft 55 by two bearings 57a and 57b.

[0080] Bearings 56a and 56b, sandwiched between roller 54 and guide roller 51a, overlap axially on roller 54. Specifically, bearing 56b overlaps on top of bearing 56a. That is, the two bearings 56a and 56b overlap as upper and lower layers. Therefore, in the following description, bearing 56a may be referred to as "lower bearing 56a" and bearing 56b as "upper bearing 56b".

[0081] The bearings 57a and 57b, sandwiched between the roller 55 and the guide roller 51b, overlap in the same manner as the bearings 56a and 56b, forming two layers. Therefore, in the following description, bearing 57a may be referred to as "lower bearing 57a" and bearing 57b as "upper bearing 57b".

[0082] like Figure 7 , Figure 8As shown, the lower bearing 56a and upper bearing 56b supporting the guide roller 51a are rolling bearings (ball bearings) having an inner ring 61, an outer ring 62 surrounding the inner ring 61, and a plurality of rolling elements (balls) 63 disposed between the inner ring 61 and the outer ring 62. The lower bearing 56a and upper bearing 56b also have a pair of upper and lower seals 64 that seal the gap between the inner ring 61 and the outer ring 62. Each seal 64 is formed into a ring shape from a rubber plate, iron plate, etc. Each seal 64 extends radially inward from the upper and lower edges of the outer ring 62 (extending towards the inner ring 61) and covers the gap between the inner ring 61 and the outer ring 62. A lubricant such as grease is sealed in the gap between the inner ring 61 and the outer ring 62 covered by the seals 64. However, the front end of each seal 64 does not contact the inner ring 61. In other words, the lower bearing 56a and the upper bearing 56b are sealed bearings, or more specifically, non-contact sealed bearings.

[0083] It should be noted that the lower bearing 57a and upper bearing 57b of the support guide roller 51b are non-contact sealed bearings, the same as the lower bearing 56a and upper bearing 56b mentioned above. That is, the lower bearing 57a and upper bearing 57b have an inner ring 61, an outer ring 62, rolling elements (balls) 63 and a seal 64, and a lubricant such as grease is sealed between the inner ring 61 and the outer ring 62.

[0084] <Cover Components>

[0085] A cover member is provided on at least one side of the guide rollers 51a and 51b, either at one axial end or at the other axial end. In this embodiment, cover members are provided on both the guide rollers 51a and 51b at one axial end and at the other axial end. More specifically, a cover member 71 is provided below each of the lower bearing 56a supporting the guide roller 51a and the lower bearing 57a supporting the guide roller 51b. Furthermore, a cover member 72 is provided above each of the upper bearing 56b supporting the guide roller 51a and the upper bearing 57b supporting the guide roller 51b. In the following description, cover member 71 may be referred to as "lower cover member 71" and cover member 72 as "upper cover member 72".

[0086] Each lower cover component 71 is formed in the shape of a disc that blocks the bottom of the guide rollers 51a and 51b. On the other hand, each upper cover component 72 is formed in the shape of an annulus (an annulus with a flange) surrounding the roller shafts 54 and 55.

[0087] The lower cover component 71, located below the lower bearing 56a, is fixed to the guide roller 51a instead of the roller shaft 54. Similarly, the lower cover component 71, located below the lower bearing 57a, is fixed to the guide roller 51b instead of the roller shaft 55. Threads (external threads 71a) are formed on the outer peripheral surface of each lower cover component 71. Internal threads (internal threads 73) are formed on the inner peripheral surface of each guide roller 51a and 51b, capable of engaging with the external threads 71a formed on the lower cover component 71. The lower cover component 71 is threadedly engaged with the guide rollers 51a and 51b via the external threads 71a and the internal threads 73.

[0088] It should be noted that the means of fixing the lower cover component 71 to the guide rollers 51a and 51b are not limited to threaded connection. For example, there are also embodiments in which the lower cover component 71 is fixed to the guide rollers 51a and 51b using other fixing means such as pressing, bonding, welding, or snap-fit. However, compared to the lower cover of other embodiments that are fixed to the guide rollers 51a and 51b by other fixing means such as pressing, the lower cover component 71 of this embodiment, which is threaded to the guide rollers 51a and 51b, is fixed to the guide rollers 51a and 51b more reliably. In addition, from the viewpoint of manufacturing cost, the lower cover component 71 of this embodiment is more advantageous than the lower cover of other embodiments that are fixed to the guide rollers 51a and 51b by other fixing means such as pressing.

[0089] The lower cover component 71 of this embodiment, which is threadedly connected to the guide rollers 51a and 51b, can be attached and detached from the guide rollers 51a and 51b. Therefore, the lower cover component 71 can be installed on each guide roller 51a and 51b after the guide rollers 51a and 51b are assembled to the roller shafts 54 and 55. Furthermore, if necessary, the lower cover component 71 can be removed from the guided rollers 51a and 51b to check the inner condition of the guide rollers 51a and 51b, etc.

[0090] The upper cover component 72, located above the upper bearing 56b, is not fixed to either the roller shaft 54 ​​or the guide roller 51a. Similarly, the upper cover component 72, located above the upper bearing 57b, is not fixed to either the roller shaft 55 or the guide roller 51b. A flange-shaped support portion 62a is integrally formed around the periphery of each upper cover component 72. Furthermore, the support portion 62a of the upper cover component 72 located above the upper bearing 56b overlaps with the flange 53 of the guide roller 51a, but is not fixed to it. Likewise, the support portion 62a of the upper cover component 72 located above the upper bearing 57b overlaps with the flange 53 of the guide roller 51b, but is not fixed to it. Therefore, each upper cover component 72 does not rotate integrally with the guide rollers 51a and 51b, but can rotate along with them. In other words, each upper cover component 72 rotates with the guide rollers 51a and 51b.

[0091] The upper cover member 72, which rotates with the guide rollers 51a and 51b, may be ground down due to contact with the guide rollers 51a and 51b. Furthermore, the upper cover member 72 surrounds the roller shafts 54 and 55. Therefore, there is also a possibility that the upper cover member 72 may be ground down due to contact with the roller shafts 54 and 55. Therefore, in this embodiment, to avoid generating metal powder or the like that which may adversely affect the bearings, a resin-made upper cover member 72 is used. It should be noted that there is no concern about generating metal powder for the lower cover 71, which is fixed to the guide rollers 51a and 51b. Therefore, in this embodiment, a metal lower cover 71 is used. However, the use of a resin-made lower cover is not excluded.

[0092] There are no particular limitations on the resin material used to form the upper side cover component 72. Fluoropolymer resin is an example of a resin material that can provide excellent heat resistance, oil resistance, and low contact resistance for the upper side cover component 72. Similarly, there are no particular limitations on the metal material used to form the lower side cover component 71. Steel carbon and SUS (stainless steel) are examples of metal materials that offer excellent heat resistance, oil resistance, and are easy to process.

[0093] A lower cover member 71, positioned below the lower bearing 56a, covers the lower side of the gap between the inner ring 61 and the outer ring 62 of the lower bearing 56a. Similarly, a lower cover member 71, positioned below the lower bearing 57a, covers the lower side of the gap between the inner ring 61 and the outer ring 62 of the lower bearing 57a. Furthermore, each lower cover member 71 is positioned outside the seal 64 on the lower side of the lower bearings 56a and 57a, overlapping with the lower seal 64 on the outer side. Thus, the lower side of the gap between the inner ring 61 and the outer ring 62 of the lower bearings 56a and 57a is doubly covered by both the seal 64 and the lower cover member 71. Therefore, compared to the case where the gap between the inner ring 61 and the outer ring 62 is only covered by the seal 64, oil, dust, and other contaminants are less likely to penetrate the gap between the inner ring 61 and the outer ring 62.

[0094] An upper cover member 72, positioned above the upper bearing 56b, covers the upper side of the gap between the inner ring 61 and the outer ring 62 of the upper bearing 56b. Similarly, an upper cover member 72, positioned above the upper bearing 57b, covers the upper side of the gap between the inner ring 61 and the outer ring 62 of the upper bearing 57b. Furthermore, each upper cover member 72 is positioned outside the seal 64 on the upper side of the upper bearings 56b and 57b, overlapping with the seal 64 on the upper side of the bearings. Thus, the upper side of the gap between the inner ring 61 and the outer ring 62 of the upper bearings 56b and 57b is doubly covered by both the seal 64 and the upper cover member 72. Therefore, compared to the case where the gap between the inner ring 61 and the outer ring 62 is only covered by the seal 64, oil, dust, and other contaminants are less likely to penetrate the gap between the inner ring 61 and the outer ring 62.

[0095] As described above, the gap between the inner ring 61 and outer ring 62 of the lower bearing 56a and upper bearing 56b supporting the guide roller 51a is double-covered by a seal and a cover component. Specifically, the lower side of the gap is double-covered by a seal 64 and a lower cover component 71, and the upper side of the gap is double-covered by another seal 64 and an upper cover component 72. As a result, regarding the gap between the inner ring 61 and outer ring 62 of the lower bearing 56a and upper bearing 56b, oil, dust, etc., are difficult to penetrate from either the lower or upper side, thus increasing the lifespan (especially the lubrication life) of the lower bearing 56a and upper bearing 56b.

[0096] Similarly, the gap between the inner ring 61 and outer ring 62 of the lower bearing 57a and upper bearing 57b supporting the guide roller 51b is double-covered by a seal and a cover component. Specifically, the lower side of the gap is double-covered by a seal 64 and a lower cover component 71, and the upper side of the gap is double-covered by another seal 64 and an upper cover component 72. As a result, oil, dust, etc., are difficult to penetrate the gap between the inner ring 61 and outer ring 62 of the lower bearing 57a and upper bearing 57b, whether from the lower or upper side, thus increasing the lifespan (especially the lubrication life) of the lower bearing 57a and upper bearing 57b.

[0097] according to Figure 7It is understood that a lower side cover member 71 is provided at the lower part of the cylindrical guide rollers 51a and 51b, and an upper side cover member 72 is provided at the upper part. As a result, an annular space is formed around the lower part of the roller shaft 54, and the lower side bearing 56a and the upper side bearing 56b are housed within this space. Additionally, an annular space is formed around the lower part of the roller shaft 55, and the lower side bearing 57a and the upper side bearing 57b are housed within this space. In other words, the guide rollers 51a, the lower side cover member 71, and the upper side cover member 72 form a housing space around the roller shaft 54 ​​to house the lower side bearing 56a and the upper side bearing 56b. Furthermore, the guide rollers 51b, the lower side cover member 71, and the upper side cover member 72 form a housing space around the roller shaft 55 to house the lower side bearing 57a and the upper side bearing 76b. Therefore, lubricant can also be filled into these housing spaces. By filling the space containing the lower bearings 56a, 57a and the upper bearings 56b, 57b with lubricant, it is possible to expect a further increase in the lifespan of these bearings 56a, 57a, 56b, 57b.

[0098] As described above, according to this embodiment, it is possible to increase the lifespan of the bearings used in the stretching machine 5. This effect is effective regardless of the type of film stretched by the stretching machine 5, but it is particularly effective when the film stretched by the stretching machine 5 contains oil.

[0099] As an example of a membrane containing oil, a resin membrane used in the separator of a lithium-ion secondary battery can be cited. The separator is disposed between the positive and negative plates of the lithium-ion secondary battery, insulating them. Therefore, the resin membrane used in the separator requires insulating properties. In addition to insulating properties, the resin membrane used in the separator also requires the ability to allow the electrolyte and lithium ions to pass through smoothly. Therefore, the resin membrane used in the separator has multiple pores.

[0100] One method for manufacturing an insulating resin film that meets the above requirements is as follows: A plasticizer is added to a solvent mixed with a resin material (hereinafter referred to as "raw material resin") that serves as the raw material for the insulating resin film. This plasticizer is a non-volatile solvent capable of forming a homogeneous solution at a temperature above the melting point of the raw material resin, and is composed of a material that can be extracted and removed after film formation. Examples of such plasticizers include liquid paraffin, paraffin wax, and other oily substances.

[0101] In use Figure 1 In the case of manufacturing an insulating resin film for a separator in a lithium-ion secondary battery using the thin film manufacturing system 1 shown, the raw resin and a solvent containing the aforementioned plasticizer are compounded using an extrusion unit 2. The raw resin (compound) obtained by compounding with the solvent passes through a T-die 3 and a material roll cooling device 4 to form a film 8. The film 8 is fed to a stretching machine 5 and stretched. Then, the plasticizer contained in the film 8 is extracted and removed by a washing process.

[0102] In the above process, the film 8 supplied to the stretching machine 5 contains a plasticizer as an oil component. A portion of the oil component contained in the film 8 seeps out to the surface of the film 8 during the stretching process. The oil component that seeps out to the surface of the film 8 adheres to the linkage mechanism 11 and reaches the guide roller via various parts of the linkage mechanism 11.

[0103] If the film containing oil is 8 Figure 1 When the heat treatment section 9 is heated, a large amount of oil seeps out from the membrane 8. Furthermore, within the heat treatment section 9, which has a higher temperature than the surrounding environment, the oil seeping out from the membrane 8 vaporizes and floats within the heat treatment section 9. Therefore, in the aforementioned manufacturing process, when the connecting rod mechanism 11 passes through the heat treatment section 9, oil is particularly prone to adhering to various parts of the connecting rod mechanism 11.

[0104] A portion of the oil adhering to the linkage mechanism 11, for example via Figure 6 The roller holding part 31a, roller shaft 54, etc., shown reach the guide roller 51a. Additionally, another portion of the oil adhering to the linkage mechanism 11 passes through... Figure 6 The roller holding part 31a, roller shaft 55, etc. shown reach the guide roller 51b. If the oil reaching the guide roller 51a and guide roller 51b invades the inside of the guide roller 51a and guide roller 51b and further invades the inside of the lower bearing 56a and 57a and the upper bearing 56b and 57b (the gap between the inner ring 61 and the outer ring 62), the lubricant sealed in these bearings will leak or the leakage of lubricant will be promoted.

[0105] The lubricant used in bearings such as the lower bearing 56a is, for example, fluorinated grease. However, fluorinated grease has low affinity for oils such as liquid paraffin and paraffin wax. Therefore, if oil (liquid paraffin, paraffin wax, etc.) seeps out from the membrane 8 and enters the interior of bearings such as the lower bearing 56a, the fluorinated grease sealed in these bearings will either flow out or be facilitated to flow in. As a result, the life (especially the lubrication life) of bearings such as the lower bearing 56a is shortened.

[0106] In this embodiment, a cover component is provided to prevent or suppress the intrusion of oil and dust into the bearings such as the lower bearing 56a used in the stretching machine 5. As a result, even if oil adhering to the linkage mechanism 11, etc., reaches the guide rollers such as the guide rollers 51a and 51b as described above, the intrusion of the oil into the bearings supporting the guide rollers can be prevented or suppressed, thus extending the bearing life.

[0107] Here, the effect of the oil contained in the membrane 8 on the bearings used in the stretching machine 5 is explained using the bearings supporting the guide rollers 51a and 51b as an example. However, the oil contained in the membrane 8 may also have the same effect on other bearings used in the stretching machine 5 (e.g., the bearings supported by the guide rollers 52a and 52b).

[0108] The invention described above by the inventors of this application has been specifically explained based on the embodiments and examples. However, the invention is not limited to the above embodiments or examples, and various modifications can be made without departing from its spirit. For example, the guide rollers of each linkage mechanism 11 are not limited to flanged rollers. In addition, the bearings supporting the guide rollers are not limited to non-contact ball bearings, but may also be contact sealed bearings, for example.

[0109] Explanation of reference numerals in the attached figures

[0110] 1 Thin Film Manufacturing System

[0111] 2. Extrusion device

[0112] 3 T-shaped mold

[0113] 4. Material roll cooling device

[0114] 5. Stretching machine

[0115] 6. Traction device

[0116] 7. Winding device

[0117] 8. Membrane

[0118] 9. Heat Treatment Department

[0119] 10, 10R, 10L linkage devices

[0120] 11. Linkage Mechanism

[0121] Tracks 13 and 14

[0122] 15, 16, 17 sprockets

[0123] Areas 20A, 20B, and 20C

[0124] 21 Clips

[0125] 22 Upper side link plate

[0126] 23 Lower side link plate

[0127] 24, 24a, 24b Track supports

[0128] 25 Base components

[0129] Roller holding section 31a, 31b

[0130] Shafts 32a and 32b

[0131] 33, 34 Column Rings

[0132] 33a, 33b Connecting parts

[0133] 34-post ring

[0134] 41 Main body

[0135] 42 Control Department

[0136] 43 Spring section

[0137] Guide rollers 51a, 51b, 52a, 52b

[0138] 53 Flange

[0139] 54 and 55 rollers

[0140] 56a and 57a bearings (lower side bearings)

[0141] 56b and 57b bearings (upper side bearings)

[0142] 61 Inner Circle

[0143] 62 Outer ring

[0144] 63 Rolling elements (ball bearings)

[0145] 62a Support section

[0146] 64 Seals

[0147] 71. Cover component (lower cover component)

[0148] 71a External Thread

[0149] 72. Cover component (upper side cover component)

[0150] 73 Internal Thread

[0151] L1, L2 separation distance

[0152] P1, P2 interval

Claims

1. A link mechanism characterized by comprising: a pair of rail supports; a base member spanning the pair of rail supports; a link plate rotatably connected at one end to one of the pair of rail supports and at the other end to another link mechanism; and a clip provided at one end of the base member and holding a film, each of the rail supports has: a guide roller open at both axial ends and moving along a rail while rotating; a shaft inserted into the guide roller; a bearing interposed between the guide roller and the shaft and rotatably supporting the guide roller; and a cover member provided at least one of an axial one end side and an axial other end side of the guide roller and covering the bearing, the bearing has an inner ring, an outer ring, a rolling element disposed between the inner ring and the outer ring, and a seal covering a gap between the inner ring and the outer ring in which a lubricant is enclosed, the cover member is disposed outside the seal in a manner overlapping the seal, the gap of the bearing is doubly covered by the seal and the cover member.

2. A link mechanism characterized by comprising: a pair of rail supports; a base member spanning the pair of rail supports; a link plate rotatably connected at one end to one of the pair of rail supports and at the other end to another link mechanism; and a clip provided at one end of the base member and holding a film, each of the rail supports has: a guide roller open at both axial ends and moving along a rail while rotating; a shaft inserted into the guide roller; a plurality of bearings interposed between the guide roller and the shaft and rotatably supporting the guide roller; and a plurality of cover members provided at both axial ends of the guide roller and covering the bearings, the plurality of bearings includes a first bearing and a second bearing overlapping the first bearing in an axial direction of the shaft, the bearing has an inner ring, an outer ring, a rolling element disposed between the inner ring and the outer ring, and a seal covering an upper side of a gap between the inner ring and the outer ring, the plurality of cover members includes a first cover member disposed below the first bearing and a second cover member disposed above the second bearing, the first cover member is formed in a disc shape closing a bottom of the guide roller, the second cover member is formed in a ring shape surrounding the shaft.

3. The link mechanism according to claim 2, characterized in that: the first cover member is not fixed to the shaft but is fixed to the guide roller, the second cover member is not fixed to either of the shaft and the guide roller.

4. The link mechanism according to claim 2, characterized in that: a space formed by the guide roller, the first cover member, and the second cover member and accommodating the first bearing and the second bearing is filled with a lubricant. ​ ​ ​ ​ ​ ​ 5. The link mechanism according to claim 2, wherein the first cover member is made of metal or resin, and the second cover member is made of resin.

6. The link mechanism according to claim 2, wherein threads are formed on the outer peripheral surface of the first cover member and the inner peripheral surface of the guide roller, respectively, the first cover member is threadedly engaged with the guide roller.

7. The link mechanism according to claim 2, wherein a flange is provided on the one end side of the guide roller in the axial direction so as to overlap the track, a support portion is provided on the peripheral edge of the second cover member so as to overlap the flange of the guide roller.

8. A linkage arrangement characterised in that, The link device is used in a stretching machine for stretching a film, and has: a track; and a plurality of link mechanisms which are connected in a manner of forming a ring chain and are movable along the track, each of the link mechanisms has: a pair of track supports; a base member which straddles the pair of track supports; a link plate which is rotatably connected at one end to one of the pair of track supports and is rotatably connected at the other end to another link mechanism; and a clip which is provided at one end of the base member and holds the film, each of the track supports has: a guide roller which is open at both ends in the axial direction and is movable along the track while rotating; a shaft which is inserted into the guide roller; a bearing which is interposed between the guide roller and the shaft and rotatably supports the guide roller; and a cover member which is provided at least one of the one end side and the other end side of the guide roller in the axial direction and covers the bearing, the bearing has an inner ring, an outer ring, a rolling element which is disposed between the inner ring and the outer ring, and a seal member which covers a gap between the inner ring and the outer ring and in which a lubricant is enclosed, the cover member is disposed outside the seal member in a manner of overlapping the seal member, the gap of the bearing is doubly covered by the seal member and the cover member. The link device is used in a stretching machine for stretching a film, and has: a track; and 9. A linkage arrangement characterised in that, a plurality of link mechanisms which are connected in a manner of forming a ring chain and are movable along the track, each of the link mechanisms has: a pair of track supports; a base member which straddles the pair of track supports; a link plate which is rotatably connected at one end to one of the pair of track supports and is rotatably connected at the other end to another link mechanism; and a clip which is provided at one end of the base member and holds the film, each of the track supports has: a guide roller which is open at both ends in the axial direction and is movable along the track while rotating; a shaft which is inserted into the guide roller; a plurality of bearings which are interposed between the guide roller and the shaft and rotatably support the guide roller; and a plurality of cover members which are provided at the one end side and the other end side of the guide roller in the axial direction and cover the bearings, the plurality of bearings include a first bearing and a second bearing which overlaps the first bearing in the axial direction of the shaft, the second bearing is disposed on the one end side of the guide roller in the axial direction. ​ ​ ​ The bearing has an inner ring, an outer ring, a rolling element disposed between the inner ring and the outer ring, and a seal covering an upper side of a gap between the inner ring and the outer ring, The plurality of cover members includes a first cover member disposed below the first bearing and a second cover member disposed above the second bearing, The first cover member is formed in a disc shape to block a bottom of the guide roller, The second cover member is formed in a ring shape to surround the shaft.

10. A stretching machine characterized by The stretching machine stretches a film, The stretching machine has a pair of link mechanisms that perform conveyance and stretching of the film, Each of the link mechanisms has a track and a plurality of link mechanisms that are linked in a manner to constitute a ring chain and are movable along the track, Each of the link mechanisms has a pair of track supports, a base member that straddles the pair of track supports, a link plate that is rotatably linked to one of the pair of track supports at one end and is rotatably linked to another link mechanism at the other end, and a clip that is provided to one end of the base member and grips the film, Each of the track supports has a guide roller that is open at both axial ends and moves along the track while rotating, a shaft that is inserted into the guide roller, a bearing that is interposed between the guide roller and the shaft and rotatably supports the guide roller, and a cover member that is provided to at least one of an axial one end side and an axial other end side of the guide roller and covers the bearing, The bearing has an inner ring, an outer ring, a rolling element disposed between the inner ring and the outer ring, and a seal covering a gap between the inner ring and the outer ring, in which a lubricant is enclosed, The cover member is disposed outside the seal in a manner to overlap the seal, The gap of the bearing is doubly covered by the seal and the cover member.

11. A stretching machine characterized by The stretching machine stretches a film, The stretching machine has a pair of link mechanisms that perform conveyance and stretching of the film, Each of the link mechanisms has a track and a plurality of link mechanisms that are linked in a manner to constitute a ring chain and are movable along the track, Each of the link mechanisms has a pair of track supports, a base member that straddles the pair of track supports, a link plate that is rotatably linked to one of the pair of track supports at one end and is rotatably linked to another link mechanism at the other end, and a clip that is provided to one end of the base member and grips the film, Each of the track supports has a guide roller that is open at both axial ends and moves along the track while rotating, a shaft that is inserted into the guide roller, a plurality of bearings that are interposed between the guide roller and the shaft and rotatably support the guide roller, and a plurality of cover members that are provided to an axial one end side and an axial other end side of the guide roller and cover the bearings, The plurality of bearings includes a first bearing and a second bearing that overlaps the first bearing in an axial direction of the shaft, ​ ​ ​ ​ The bearing has an inner ring, an outer ring, rolling elements disposed between the inner ring and the outer ring, and a seal covering an upper side of a gap between the inner ring and the outer ring, The plurality of cover members includes a first cover member disposed below the first bearing and a second cover member disposed above the second bearing, The first cover member is formed in a disc shape to block a bottom of the guide roller, The second cover member is formed in a ring shape to surround the shaft.

Images