APPARATUS FOR FOLDING AND PLEATING THE EDGES OF WRAPPING MATERIAL

Abstract: An ear folding apparatus for automatically fold­ ing and pleating ears (2a) of packaging material (2) wrapped around a cylindrical article (32) such as a coil of strip material is improved in that the apparatus comprises a pleats-holding/­ inside-bending guide (38) which has a radially notched section (39) and which is movable in the axial direction of the cyl­ indrical article, and a folding unit which includes a feed roll (34), a folding roll (35) and a folding claw (36).

Description: Field of the Invention: The present Invention relates to an apparatus for folding and pleating the edges of wrapping material extending over the edges of a cylindrical article being wrapped with said material and for introducing said folded and pleated edges of said wrapping material into a central bore of said cylindrical article (various types of sheet steel coils, aluminium coils and coiled ones of sheet-like products of paper, rubber, vinyl, etc.). Description of the Prior Art: In general, a metal strip coil 1 consisting of a steel strip is shipped after it has been regularly packaged by packaging material 2 for the purpose of rust-proofing and scratch-proofing as shown in Fig. 11. In the prior art, this packaging work has been achieved by hand working. The coil has its outer circumference already wrapped by a packaging paper sheet in the preceding step of process, edges 2a of the packaging paper sheet extending over the edges of said coil are folded and pleated, the central portion of the pleats is bent and stuffed into a coil bore, and finally the stuffed portion is fixed by sticking a tape or the like onto that portion. This packaging work necessitates a lot of labor and time, and hence automation of that work has been strongly required. Therefore, a number of automatic packaging apparatuses were proposed in the past. (1) For instance, in Laid-Open Japanese Patent Specification No. 61-21313 (1986) an automatic packaging apparatus is proposed, in which an edge of a packaging paper sheet extending over the edges of a coil is gripped at a plurality of points along its circumferential direction and is bent towards the center of the end surface of the coil, at the same time the main body of the apparatus is moved towards the end surface of the coil, and further the bent ear is pressed against the end surface of the coil to be folded thereon. (2) Alternatively, Laid-Open Japanese Patent Specification No. 58-134824 (1983) proposes an automatic packaging apparatus, in which while a packaging paper sheet that is preliminarily shaped to have a cross-section configuration adapted for the shape of the coil, that is, a U-shaped cross-section configuration is being wrapped around an outer circumference of a coil, edges of the packaging paper sheet are folded. In the case of the known apparatus described in numbered paragraph (1) above, folding devices equal in number to the number of pleats are necessary along the outer circumference of the coil, and moreover, since the structure and operation of the respective folding devices are complexed, a high level of control technique is required. Accordingly, manufacturing costs become relatively high and maintenance of the apparatus is complex. In the case of the known apparatus described in numbered paragraph (2) above, due to the fact that the entire apparatus becomes large because shaping of a packaging paper sheet into a U-shape in cross-section, wrapping of the packaging paper sheet around the outer circumference and folding of edges of the packaging paper sheet are performed at the same position, an interval between preceding and succeeding equipments would become broad, hence the entire manufacturing line necessitates a large space, and also application of the packaging apparatus to an existing manufacturing line is difficult. Furthermore, means for holding pleats after folding and a device for bending and stuffing the folded edges into a coil bore are necessitated separately. (3) EP-A1-0 001 171 discloses, an apparatus for folding and pleating the edges of wrapping material extending over the edges of a cylindrical article being wrapped with said material, and for introducing said folded and pleated edges of said wrapping material into a central bore of the cylindrical article, said apparatus, comprising a folding unit, and a fold wrapping guiding means having a shaft and a guiding element. (4) WO-A1-83/01 429 describes, an edge folder by means of which the edge of a wrapping material which is wound around a cylindrical object is folded against the end of a roll. In this device, the folding takes place by utilizing pressing means attached to an endless chain, which pressing means are mounted to the chain by means of articulated joints so that the pressing means can pivot freely to a relative angle of movement determined by the circumferential velocity of the roll and the speed movement of the chain. The roll is rotated, and, at the same time, the edge folder is pressed against the end of the roll and the chain is operated so that its direction of movement is from the circumference of the roll towards the centre. SUMMARY OF THE INVENTION: The object of the present invention is to provide an apparatus for folding and pleating the edges of wrapping material extending over the edges of a cylindrical article being wrapped with said material and for introducing said folded and pleated edges of said wrapping material into a central bore of said cylindrical article, which is relatively simple in structure and operation, of low cost, and not complex in maintenance, performing wrapping action in good quality and which is not large-sized as a whole so that the entire manufacturing line including the apparatus does not require a large space, and which can be readily applied to an existing manufacturing line. The above mentioned object is solved by the features defined in the characterising portion of the main claim. Useful improvements of the subject-matter of the main claim are defined in subclaims 2-7. The apparatus according to the present invention operates in the following manner: when a coil having packaging material wrapped around its outer circumference has been placed at a predetermined position, the pleats-holding/inside-bending guide acting as a guiding element is pressed against the side surface of the coil, and the folding unit having pressing means such as a feed roll, a folding roll and a folding claw assembled therein swings while it is pressing the edge of the packaging material extending over the edge of the coil, and it comes into pressure contact with the side surface of the coil via the pleats-holding/inside-bending guide. Subsequently, the folding unit and the coil perform relative rotation to each other about the axis of the coil, likewise the above-mentioned respective rolls also rotate about their own axes, the pressing means such as the folding claw is also engaged with the packaging material to perform edge folding operation, the folded edge portions are successively led to the inside of the pleats-holding/inside-bending guide through its radially notched section while the relative rotation is effected, and the edge end portion is bent and stuffed into an inner bore of the coil by the pleats-holding/inside-bending guide. Since apparatus for folding and pleating the edges of wrapping material according to the present invention is constructed and operates as described above, it is compact in mechanical construction, and hence it can be applied not only to a newly installed manufacturing line but also even to an existing manufacturing line for the purpose of folding edges of packaging material that has been preliminarily wrapped around a cylindrical product. Moreover, it is possible to fold edges along the entire circumference by means of one set of folding unit, hence the structure of the apparatus is simple, reduction of the manufacturing cost of the apparatus can be achieve, and at the same time, since the folding of edges can be performed continuously by relative rotation between the coil and the ear folding apparatus, the operation is speedy and smooth, so that automation of packaging of a coil can be realized. The above-mentioned features and advantages of the present invention will become more apparent by reference to the following description of preferred embodiments of the invention taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS: In the accompanying drawings: Fig. 1 is a side view showing a general construction of a first preferred embodiment of the apparatus for folding and pleating the edges of wrapping material according to the present invention; Fig. 2 is a schematic view showing an operating state of the apparatus in Fig. 1; Fig. 3 is an enlarged partial perspective view for explaining an edge folding operation in the apparatus shown in Fig. 1; Fig. 4 is a developed view showing a bending operation for a folded edge end into an inner bore of a coil; Figs. 5 and 6 are schematic perspective views showing an edge folding operation of the apparatus in Fig. 1; Fig. 7 is a perspective view of a pleats-holding/ inside-bending guide; Fig. 8 is a perspective view of explaining a edge folding, bending and stuffing operation as viewed in the direction of arrow A in Fig. 6; Fig. 9 is a side view of a second preferred embodiment of the present invention; Fig. 10 is a front view of the apparatus shown in Fig. 9; and Fig. 11 is a schematic view showing the state where packaging material has been wrapped around a coil. DESCRIPTION OF THE PREFERRED EMBODIMENTS: (First Preferred Embodiment) Referring now to Figs. 1 to 8, a construction and the operation of an apparatus for folding and pleating the edges of wrapping material according to a first preferred embodiment of the present invention are illustrated. In the figures, reference numeral 2 designates packaging material, numeral 2a designates an edge, numeral 31 designate a cradle roll, numeral 32 designates a coiled article to be packaged, numeral 33 designates a folding unit, numeral 34 designates a feed roll, numeral 35 designates a folding roll, numeral 36 designates a folding claw, numeral 37 designates a movable shaft, numeral 38 designates a pleats-holding/inside-bending guide acting as a guiding element, numeral 39 designates a notched section in the guide 38, numeral 40 designates a guide cylinder, numeral 41 designates an inner bore of the coil (or simply coil bore), numeral 42 designates a gap space between the outer circumferential surface of the guide cylinder 40 and the inner circumferential surface of the coil bore 41, numeral 43 designates a projected portion of the guide 38, numeral 44 designates slant portion of the guide 38, numeral 45 designates side surface pressing rolls, numeral 46 designates inner surface pressing rolls, numeral 47 designates a speed reduction motor, numeral 48 designates a mount shaft for the folding claw 36, numeral 49 indicates a bent and stuffed state of the packaging material into the coil bore, and numeral 63 indicates a folded and pleated state of the ear 2a. A coiled article to be packaged 32 (hereinafter simply called "coil") is placed on a plurality of cradle rolls 31 which are disposed preliminarily, and it can be rotated by a driving device for these rolls 31. Above the both side surfaces of the coil 32 are disposed folding units 33 each consisting of a feed roll 34, a folding roll 35 and a folding claw 36 in such manner that they can be brought into pressure contact with the side surfaces of the same coil by swinging about their pivotal shafts and also that they are adjustable in position in the upper and lower directions and the widthwise directions of the coil 32 to be able to perform edge folding operations even if the diameter and the width of the coil are varied. On the other hand, a movable shaft 37 is disposed in opposition to the side surface of the coil 32, and at the tip end of the shaft 37 is mounted a pleats-holding/inside-bending guide 38 having a notched section 39 and a guide cylinder 40. The movable shaft 37 is disposed so as to be adjustable in position in the upper and lower directions and the widthwise directions of the coil so that the pleats-holding/inside-bending guide 38 can be positioned at the center of the coil even if the diameter and the width of the coil are varied, and provision is made such that when the movable shaft 37 is moved towards the coil 32, the pleats-holding/inside-bending guide 38 may be pressed against the side surface of the coil with a predetermined gap space 42 retained between an outer wall surface of a guide cylinder 40 and an inner wall surface of a coil bore 41. Now, explaining about the pleats-holding/inside-bending guide 38 in more detail, as shown in Fig. 7, the guide 38 includes a notched section 39 for guiding a folded and pleated portion 63 formed by folding the 2a from the front side to the rear side of the pleats-holding/inside-bending guide 38. Along one edge of this notched section 39 is provided a projected portion 43 for facilitating the guiding, and the guide cylinder 40 has such configuration that it continuously transfers to a rounded slant portion 44 and it extends along the inner wall surface of the coil bore 41 with the above-mentioned gap space 42 retained therebetween. It is to be noted that the pleats-holding/inside-bending guide 38 could be provided with side surface pressing rolls 45 and the guide cylinder 40 could be provided with inner surface pressing rolls 46 to smoothen the rotation of the guide 38, but the guide 38 should not be limited to the illustrated configuration, and especially, the guide cylinder 40 can be formed as a separate member from the pleats-holding/inside-bending guide 38. In addition, the folding claw 36 is adapted to swing as shown by arrows B when a mount shaft 48 therefor is rotated as by a crank mechanism coupled to a speed reduction motor 47, as shown in Fig. 3. In the above-described apparatus, when a coil 32 having packaging material 2 wrapped therearound is loaded on cradle rolls 31, a pleats-holding/inside-bending guide 38 which has its operating position adjusted preliminarily depending upon a diameter and a width of the coil, is pressed against a side surface of the coil 32 by a movable shaft 37 with a gap space 42 retained between a guide cylinder 40 and an inner wall surface of a coil bore 41. Next, a folding unit 33 (including a feed roll 34, a folding roll 35 and a folding claw 36) which has its operating position likewise adjusted depending upon the diameter and the width of the coil, swings to press an edge 2a of packaging material 2 and to bring the edge 2a into pressure contact with the pleats-holding/inside-bending guide 38 that is preset on the side surface of the coil. Subsequently, the coil 32 is rotated as a result of rotation of the cradle rolls 31, at the same time the feed roll 34 and the folding roll 35 respectively coupled to a driving device are also rotated, and by supporting and feeding the edge 2a of the packaging material 2 which was brought into pressure contact with the pleats-holding/ inside-bending guide 38 by means of the feed roll 34 and the guide 38, a sag 64 is created between the feed roll 34 and the folding roll 35 because a difference in a circumferential length due to a difference of a radius is produced between the packaging material portions located at the outer circumference of the coil and on the side of the inner bore of the coil. By making this sag 64 to be bitten by the folding roll 35 at a predetermined pitch by means of the folding claw 36, the edge 2a is successively folded and pleated on the side surface of the coil as indicated by reference numeral 63. Meanwhile, owing to the rotation of the cradle rolls 31, the folded and pleated portions are successively guided through the notched section 39 of the pleats-holding/ inside-bending guide 38 onto the slant portion 44 of the guide cylinder 40 on the inside of the guide 38 as shown in Figs. 4 and 8. The slant portion 44 has a trumpet-shaped configuration, hence the inner portion of the folded and pleated edge 2a is guided into the gap space 42 on the outside of the guide cylinder 40 as a result of rotation of the coil 32, and it turns round along the inner wall surface of the coil bore 41. Thus, simultaneously with the folding and pleating of the edge 2a, bending and stuffing of the edge 2a into the coil bore 41 are carried out continuously as shown at 49 in Fig. 4. When the folding and pleating 63 of the edge have been finished over the entire circumference, the edge 2a has entirely entered to the inside of the pleats-holding/ inside-bending guide 38 through the notched section 39 of the same guide 38. Then, if the cradle rolls 31 are stopped, the folding unit 33 (including the feed roll 34, the folding roll 35 and the folding claw 36) is swung to the above and thereafter the pleats-holding/inside-bending guide 38 is moved to the left, then the apparatus returns to the initial state. (Second Preferred Embodiment) A second preferred embodiment of the present invention is illustrated in Figs. 9 and 10 as a side view and a front view, respectively. This second preferred embodiment differs from the above-described first preferred embodiment only in that a coil 32 is fixedly mounted and the folding and pleating 63 of an edge are carried out while a folding unit 51 is revolving about the center axis of the coil along the side surface of the coil. The coil 32 is placed on a V-shaped fixed coil cradle 52, and the folding unit 51 consisting of a feed roll, a folding roll and a stuffing member such as a folding claw similarly to the above-described first preferred embodiment, is swingably mounted on a disc-shaped frame 53. This frame 53 has its circumferential portion held by means of a plurality of small-sized roll-like bearings 55 and its central portion supported by a bearing 56, at the center of the frame 53 is provided a hollow shaft 54, and a gear is fixedly fitted around the hollow shaft 54 and is adapted to be rotated by an electric motor 57. In addition, a movable shaft 58 having a pleats-holding/inside-bending guide 38 mounted at its remote end is slidably inserted into the hollow shaft 54. This movable shaft 58 can be extended or contracted by means of a cylinder 59 to be adapted to the position of the side surface of the coil 32, and thereby the position of the pleats-holding/inside-bending guide 38 can be adjusted. Also, in order that the disc-shaped frame 53 and the movable shaft 58 supporting the pleats-holding/ inside-bending guide 38 can rotate integrally, a whirl-stop 60 is provided, and for the purpose of enabling the apparatus for folding and pleating the edges of wrapping material to adapt to variations in a diameter and a width of a coil, the roll-like bearings 55 holding the frame 53, the bearing 56 and the motor 57 are fixedly mounted on vertically movable adjusting devices 61 which are in turn placed on a truck 62 so as to be movable in the horizontal directions. In operation, the above-described apparatus for folding and pleating the edges of wrapping material has its height preliminarily adjusted by the adjusting devices 61 so as to match with the coil 32 having packaging material 2 wrapped therearound which has been loaded on the coil cradle 52. The pleats-holding/ inside-bending guide 38 and the folding unit 51 advance towards the side surface of the coil 32 as carried by the truck 62, and the pleats-holding/inside-bending guide 38 comes into contact with the side surface of the coil 32. The guide 38 is further pressed against the side surface of the coil 32 by the action of the cylinder 59. Next, the folding unit 51 swings, and while the edge 2a of the packaging material 2 is being pressed by the feed roll and the folding roll, the edge 2a is brought into pressure contact with the side surface of the coil by the intermediary of the pleats-holding/inside-bending guide 38. Then the disc-shaped frame 53 rotates about its axis aligned with the center axis of the coil bore, at the same time the feed roll, folding roll and folding claw operate, and similarly to the above-described first preferred embodiment, while the folding and pleating 63 of the edge 2a are being carried out, the folded and pleated edge 2a is guided through the notched section 39 of the pleats-holding/inside-bending guide 38 to the inside of the same guide 38 as a result of rotation of the frame 53, and the pleated portions of the edge 2a are successively bent and stuffed into the coil bore 41. At the time point when the folding and pleating 63 of the edge 2a over its entire circumference have been completed, the pleats-holding/inside-bending guide 38 is positioned outside of the edge 2a, hence after the folding unit 51 is made to swing outwards, the pleats-holding/ inside-bending guide 38 and the folding unit 51 are retreated to a standby position as carried by the truck 62.

Claims: An apparatus for folding and pleating the edges of wrapping material (2) extending over the edges of a cylindrical article (32) being wrapped with said material (2) and for introducing said folded and pleated edges of said wrapping material (2) into a central bore (41) of said cylindrical article (32), said apparatus comprising: (a) a folding unit (33), and (b) a fold wrapping guiding means (37, 38) having a shaft (37) which is coaxially disposed with respect to the axis of said bore (41), said shaft (37) having a guiding element (38) mounted at its tip end, being provided to bend and introduce the folded and pleated wrapping material (2) into said folding unit (33), said fold wrapping guiding means (37, 38) being mounted to perform a relative rotation with respect to said cylindrical article (32) about its axis, characterized in that (c) said guiding element (38) has a notched section (39) along one edge of which is provided an outwardly projecting slanted guiding surface projecting inwardly from said guiding element (38) and into said central bore (41) of said article (32), (d) said fold wrapping guiding means (37, 38) is movable into its operative position so that there is a gap (42) between said slanted guiding surface (44) and said bore (41) and between said guiding element (38) and the edge of said cylindrical article (32), (e) said folding unit (33) which is pivotably movable into its operative position comprises a rotating feed roll (34) for guiding the extending area of wrapping material (2) into pressure contact with said guiding element (38), a rotating folding rail (35) is provided for feeding the creases of said wrapping material (2) which are created by said folding unit (33) into said notched section (39) such that said extending wrapping material (2) is gathered between said feed roll (34) and said folding roll (35), and a folding claw (36) is disposed between said feed roll (34) and said folding roll (35), said folding claw being adapted to oscillate towards said wrapping material (2) to introduce said successively gathered portions as said material into said gap (42) between said folding roll (34) and said guiding element (38) to create said folded and pleated edges of the wrapper such that their free edges are fed out to said slanted surface (44) and extend into said gap (42) between said slanted guiding surface (44) and the bore (41) of said article (32). Apparatus according to claim 1, characterized in that said cylindrical article (32) to be wrapped is adapted to rotate around its own cylinder axis. Apparatus according to claim 1, characterized in that said guiding element (38) and said folding unit (33) are adapted to be rotated around the cylinder axis of said cylindrical article (32) to be wrapped. Apparatus according to claim 1, 2, or 3, characterized in that said guiding element (38) is disposed to be adjustable in position in the upper and lower directions and in the widthwise directions of said cylindrical article (32) to be wrapped. Apparatus according to claim 1, characterized in that said guiding element (38) is a pleats-holding/inside bending guide plate comprising: an inner guide cylinder (40) which is coaxially disposed on the side of the guiding element (38) and oriented to said face of said cylindrical article (32), said inner guide cylinder fitting into said center bore (41) with a predetermined gap (42), and having said slanted portion (44), the radially notched section (39), through which the portions of said wrapping material (2) which are folded and pleated by said folding unit (33) are successively guided through onto said slanted surface (44) of said guide cylinder (40) Apparatus according to claim 5, characterized in that said pleats-holding/inside-bending guide (38) is provided with side surface pressing rails (45). Apparatus according to claim 5, characterized in that said guide cylinder (40) is provided with inner surface pressing rails (46).

Inventors: FUJII, ISAO MIHARA MACHINERY WORKS, OKAMOTO, MASATO MIHARA MACHINERY WORKS, OSADA, SANJYURO MIHARA MACHINERY WORKS, YAMAMOTI, KOUICHI MIHARA MACHINERY WORKS
Applicants: MITSUBISHI JUKOGYO KABUSHIKI KAISHA
Application year: 1987
Main classification: B65B51
IPC codes: B65B49, B65B25, B65B11