JPH0571692B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to a method and apparatus for treating the tip of a plastic tie rope for use as a strap for a shopping bag. Specifically, the plastic binding rope that makes up the main body of the strap for a shopping bag is firmly attached to both ends of the plastic binding rope, which is then cut to an appropriate length to be used as a strap for a shopping bag. The present invention relates to a method and apparatus for treating the tip of a plastic tying rope for fixing a plastic string-like body constituting a hanging piece of a hand string at right angles. Here, the above-mentioned plastic tying rope for carrying hand strings is a plastic film rope made by loosely twisting plastic films together, such as rope yarns made of stretched polypropylene film with appropriate twists. A three-strike rope with a thickness of about 8 mm is made by twisting the three strands into a strand, then gently twisting the three strands into a Z-twist, and then lightly heat welding them in the appropriate places to join them. In addition, the above-mentioned plastic string-like body is, for example, a stiff, hardened material obtained by heat-compressing the above-mentioned three-stripe rope under certain conditions so that the outer diameter becomes about 2/3 or less. It is a rope (Utility Application No. 58-42703 filed by the applicant). [Prior Art] Plastic binding ropes made by fully hot-stretching thermoplastic plastics, particularly polyolefin films containing polyethylene and polypropylene, and twisting them together are strong, flexible, and easy to handle. Because it hits softly against
It is widely used as a carrying strap for commercial paper bags, such as square-bottomed bags with carrying handles called shopping bags. In this case, it is necessary to fix a relatively hard member to the tip of the tying rope, which will serve as a hanging piece.In this case, as the material for the latching piece, the above-mentioned plastic tying rope is heat-compressed. It is possible to use a string-like body that has a thinner diameter and is stiff and stiff (Jetgansho
No. 58-042703). Therefore, as a method of fixing the tip of the tying rope and the side of the string-like body, the applicant first overlaps the tip of the tying rope and the side of the string-like body by a predetermined length, and then He proposed a technique for welding the joined parts together using, for example, ultrasonic irradiation.
−106388). However, in this method, the tip of the tying rope and the string-like body are overlapped and welded, so what contributes to the joining of the two is only a part of the circumferential surfaces of the two in the overlapped part. However, there were problems in that the welding strength was not necessarily sufficient, and furthermore, the overlapped portions were bulky and tended to cause trouble when attached to a paper bag. [Purpose of the Invention] Therefore, the purpose of the invention of this application is to melt the tip of the tying rope and the side of the string-like body, and then butt and join them, thereby reducing the total cross-sectional area of the tying rope and the side of the string-like body. A method for processing the tip of a tying rope and a string-like body that can be joined to a string-like body with sufficient bonding strength and not bulky by welding the side parts together, and for carrying out the method. The goal is to provide equipment for [Structure of the Invention] The structure of the first invention according to this application for achieving the above object is that plastic tying ropes are attached to both ends of the plastic tying rope that constitutes the string body of the shopping bag carrying strap. In a method for treating the tip of a plastic tying rope, which fixes at right angles a plastic string-like body obtained by firmly fixing and cutting to an appropriate length to constitute a hanging piece of a shopping bag carrying strap; When the tip of the tying rope and the side of the string-like body are brought into contact with each other via a single heater to melt and join them; the contact by the heater is such that the contact with the side of the string-like body is This starts before the contact with the tip of the tying rope, and then the molten portions generated at the tip of the tying rope and the side of the string-like body are joined to each other, and this joined portion is pinched from two directions by clamp pieces. The gist is to bring the material into contact with pressure and cool it to solidify it. On the other hand, the configuration of the second invention according to this application includes a holding device that holds the plastic string-like body in a straight line along its longitudinal direction; A gripping device that is installed vertically and grips the end of a plastic binding rope between the tongues; A heater device that has a plurality of heaters protruding in a row from the bottom surface of a plate heater; a clamp device comprising an upper clamp piece and a lower clamp piece provided; the heater of the heater device is configured to be movable in a direction perpendicular to the longitudinal direction of the string-like body; The string-like body is placed at a position where it can rub one side and the other side can come into contact with the tip end surface of the tying rope; The holding device is arranged so that the tip of the binding rope can be brought into contact with the other side of the heater and melted, and then transferred to the melting point on the side of the string-like body and joined. It is configured so that it can be set to move vertically and horizontally while maintaining parallelism;
The above-mentioned clamping device is configured such that the upper and lower clamp pieces sandwich and press the joint between the string-like body and the tip of the tying rope by rotation of the rotating shaft. The gist is that this method has been made possible to implement. [Example 1] An example of the first invention will be described below with reference to the drawings. The process of joining the tip of the plastic tying rope 1 and the string-like body 2 is carried out through the steps shown in FIG. The tying rope 1 is made by appropriately twisting a stretched polypropylene film to form a strand 1a, and then gently twisting three of the strands into a Z-twist with a thickness of approximately 8.
It is a three-stroke rope of about mm (Figure 4a). On the other hand, the string-like body 2 keeps the binding rope 1 at a temperature of 650°C.
Obtained by thermal compression treatment at ℃ and running speed of 35 to 50 m/min, bulk compression ratio 13.0%, bulk compression elastic modulus 79.5%
(However, the test method is JIS L1096, initial load
It is a stiff and strong rope with properties of about 50g/cm ² and a load of 300g/cm ² (Fig. 4b). The string-like body 2 is intermittently held in its longitudinal direction by holders 41, 41... and positioned substantially linearly, while the binding ropes 1, 1... are held near their tips by a gripping device. 30 and faces the string-like body 2 at right angles (FIG. 1a). Also,
It is assumed that the binding ropes 1, 1, . . . and the string-like body 2 form one plane. The heater 51, whose side surface facing the string-like body 2 is a slope 51a, moves in a direction perpendicular to the plane, contacts the side of the string-like body 2, and melts the same part while rubbing it. (Figure 1b, Figure 2). The area melted by the heater 51 is aligned with the area where the tip of the binding rope 1 faces. It moves in a direction approaching the gripping device 30 and the string-like body 2, and is stopped at a position where the tip of the binding rope 1 reaches and contacts the surface of the heater 51 (FIG. 1c). The tip of the binding rope 1 is melted by the heater 51. Here, the start of melting of the tip of the tying rope 1 is controlled by the string-like body 2.
The reason why the latter starts later than the melting of the side parts is that the string-like body 2 has a lower bulk compressibility and a slower melting rate. At the same time as the heater 51 is removed, the gripping device 30 is moved further and stopped at a position where the melted part at the tip of the binding rope 1 is closely joined to the melted part on the side of the string-like body 2 (FIG. 1d). Immediately thereafter, the clamp device 60 having the upper clamp piece 61a and the lower clamp piece 61b
The fused and joined portions of the tip of the binding rope 1 and the side of the string-like body 2 are very lightly pressed and cooled (FIGS. 1e and 3). If each of the above steps is carried out at the same time at both ends of a plurality of binding ropes 1, 1... of a predetermined length, a ladder will be created in which the binding ropes 1, 1... are used as the horizontal members and the string-like body 2 is used as the vertical member. By cutting the string-like body 2 at the middle of each joining point, the hanging pieces 3, 3 made of the string-like body 2 are attached to both ends of the string body made of the binding rope 1. A fixed shopping bag strap can be made (Fig. 1 f, Fig. 5). The surface temperature of the heater 51 is set to 460±10°C, and the contact of the tip of the tie rope 1 to the heater 51 is set to 460±10°C.
1 and the side of the string-like body 2 is delayed by about 0.5 seconds,
And when the time is about 4 seconds, the tie rope 1
The bonding strength between the strap and the hanging piece 3 was as shown in the table below, and sufficient strength and appearance were obtained as a strap for a shopping bag. However, the joint strength is the result of a thread strength and elongation test (Instron method), with a tensile speed of 10 cm/min and a grip interval of 4 cm. Strength (Kg), Test 2 is the strength (Kg) of a knot or joint coming out of a perforated plastic plate with a diameter of 7 mm.
Or the strength at which a knot or joint breaks (Kg)
are shown as average values for 5 or 6 samples, respectively.

[Example 2]

The tying rope tip processing device includes a heater device 50 including a heater 51, a gripping device 30 for gripping the tying ropes 1, 1, and a holder 4 for holding the string-like body 2.
1, and a clamping device 60 having upper and lower clamping pieces 61a and 61b (FIG. 6). The holding device 40 includes coarse comb-shaped holders 41 and 4.
1..., the holder plate 42 formed with the adjustment bolt 4
3 are fixed to the rotating shaft 44 through the holder plates 42, 42, which are arranged side by side as a set of upper and lower parts, with the holders 41, 41, . . . 1... is made to match the distance d at which the ends are joined. The gripping device 30 has flag-shaped tongues 31a and 32a arranged alternately on a pair of square shafts 31 and 32 that are slidable in opposite directions in a sliding bearing 33. Chamfers 31b and 32b are provided on opposite sides of the top (Figs. 7 and 6).
figure). Further, the entire gripping device 30 is placed on a table (not shown), and can be set to move vertically and horizontally while remaining parallel to the holding device 40. The interval between the gripping ropes 1 by the tongues 31a and 32a is made to match the interval d. Heaters 51, 51... are plate heaters 52
It has a prismatic shape that protrudes in a row on the lower surface of the
Heater device 50 along with a temperature control device (not shown)
It consists of The surface of the heater 51 facing the string-like body 2 has a slope 51a formed from its tip, and at a position where the surface rubs the side of the string-like body 2,
The whole can be moved up and down while remaining parallel to the holding device 40. The heater 51 and the plate heater 52 are made of heat-resistant metal materials that do not accumulate harmful oxides on their surfaces even if they are operated for a long time at a temperature of 500° C. or higher. Further, the spacing between the heaters 51, 51... is also matched to the spacing d, so that when the entire device is moved downward, each heater 51, 51... is located between each holder 41, 41... There is. The clamp device 60 consists of an upper clamp piece 61a and a lower clamp piece 61b that are arranged and fixed to rotating shafts 63a and 63b via arms 62a and 62b,
The length and shape of the arms 62a and 62b are the rotation axis 63a,
63b is rotated to close both clamp pieces 61a, 61b, the holders 41, 41... However, the relative positions of both clamp pieces 61a and 61b at the pressing position are as follows.
A slight axis deviation δ is caused in the longitudinal direction of the binding rope 1, that is, in the direction orthogonal to the holding device 40 (FIG. 3). Both clamp pieces 61a and 61b are cylindrical aluminum blocks with smooth surfaces. It is assumed that two sets of each unit having the above configuration are arranged facing each other, and the number of each part including the holders 41, 41, etc. along the longitudinal direction of the string-like body 2 is several to several dozen. It is assumed that an arbitrary number of the above can be arranged in a row. When the rotation shaft 44 is rotated several tens of degrees in the direction of the arrow in FIG. After introducing 2, the holder plates 42, 4
2 is closed to hold this string-like body 2 in a straight line. At this time, the coarse comb-shaped holders 41, 41, formed on the holder plates 42, 42, hold the string-like body 20 intermittently along its longitudinal direction,
The distance d of 1, 41, . . . is the distance between the joining position and the tip of the binding rope 1. When the two square shafts 31 and 32 of the gripping device 30 are slid in opposite directions to each other in the direction of the arrow in FIG.
As the gap becomes smaller, the binding rope 1 can be gripped and held (FIG. 6). Here, the length from each tongue piece 31a, 32a to the tip of the tying rope 1 protruding toward the string-like body 2 side is a length that can support its own weight with the stiffness of the tying rope 1, and all the tying ropes 1, 1... shall be cut all at once using a heat wire cutter device (not shown) so that they have the same dimensions. When the table (not shown) on which the gripping device 30 is placed is moved upward so that the ends of the binding ropes 1, 1... face the sides of the string-like body 2, the state shown in FIG. 1a described above is obtained. is obtained. Heater device 50 that is heated and controlled to a predetermined temperature
When lowered, the sides of the heaters 51, 51, . At this time, since the slope 51a is formed on the heater 51, when the string-like body 2 and the heater 51 come into contact, there is no risk of the former being scraped off or forced down. The gripping device 30 is moved by moving a table (not shown).
When the whole is brought closer to the string-like body 2, each tip of the binding ropes 1, 1, . (Situation shown in Figure 1c). Here, the time from when the heater 51 starts contacting the side of the string-like body 2 until the tip of the tying rope 1 contacts the heater 51, and the time during which the tying rope 1 and the string-like body 2 are in contact with the heater 51. is controlled by a control device (not shown), and is set to conditions for obtaining the optimum bonding result together with the surface temperature of the heater 51. Next, the heater device 50 is pulled upward to break the contact between the heater 51 and the binding rope 1 and the string-like body 2, and the gripping device 30 is immediately pulled up by the table.
When the ropes are further advanced toward the string-like body 2, the tips of the binding ropes 1, 1, . Closely bonded (state shown in Figure 1d). When the rotation shafts 63a, 63b are rotated in the direction of the arrow shown in FIG. 6, the upper clamp pieces 61a, 61a...
and the lower clamp pieces 61b, 61b... rotate around their respective rotation shafts 63a, 63b, and the binding rope 1
The joining point between the tip of the cord and the side of the string-like body 2 is pinched from above and below and the same point is pressed (the state shown in Fig. 1e). Here, since the joint portion is in a molten state, the pressing force between both clamp pieces 61a and 61b is extremely small. Furthermore, both clamp pieces 61a and 61b are
Since the axial center deviation δ is provided in the longitudinal direction of the tying rope 1 (Fig. 3), the tying rope 1 and the string-like body 2, especially the latter, should be pressed too much and crushed until the joining area becomes too small. There is little risk of it getting lost. Since both clamp pieces 61a and 61b are made of aluminum ingots, they have high thermal conductivity and effectively remove heat from the melted parts, promoting cooling and solidification of the joined parts. Furthermore, since the surface is finished smooth, it is extremely unlikely that the molten binding rope 1 or string-like body 2 will adhere to it. Each unit that performs the above functions is arranged in two sets facing each other, so that the binding ropes 1, 1...
The processing for both ends of the string body 2 can proceed at the same time, and the number of bundles corresponding to the number of each part including the holders 41, 41, etc. arranged in the longitudinal direction of the string body 2 can be processed simultaneously. rope 1, 1... 1
This can be done in units of batch processing. Therefore, if steps a to e in Figure 1 are followed, Figure 1 f is obtained.
The ladder-like intermediate product shown in is obtained. By cutting the string-like body 2 at the middle of each joining point, a shopping bag holder is created in which the hooking pieces 3, 3 made of the string-like body 2 are fixed to both ends of the string body made of the binding rope 1. You can make hand strings (Figure 1 f, Figure 5). The order of operation of each element constituting the above-mentioned apparatus, the timing of its operation, and other incidental controls are controlled in an integrated manner by a control device (not shown), thereby making it possible to configure a fully automatic apparatus. [Effects of the Invention] As explained above, according to the first invention of this application, the tip of the tying rope and the side part of the string-like body are melted, and then the two are butted and joined to form a tying. Since the entire cross-sectional area of the rope can contribute to the joint strength, the joint strength is sufficient, and since there are no overlapping parts, the binding rope and string-like body can be joined without being bulky at the joint. It has excellent effects. On the other hand, according to the second invention, not only can the first invention be carried out, but also the movement of each component can be simplified, and the end treatment of a large number of tying ropes can be performed at the same time, so the operation order, operation timing, etc. The effect is that fully automatic mass-production machines can be easily realized by controlling them in an integrated manner.

[Brief explanation of drawings]

1 to 3 show an embodiment of the first invention, a to e in FIG. 1 are explanatory diagrams of each step,
In the same figure, f is an explanatory diagram showing the situation in which intermediate products are lowered into final products, Fig. 2 is a view taken along the line X-X in Fig. 1b, and Fig. 3 is a view taken along the Y-Y line in Fig. 1e. This is a perspective view.
FIG. 4 is an external view and a sectional view showing the material to which the first invention is applied, in which figure a shows the binding rope 1 and figure b shows the string-like body 2. FIG. 5 is an external view showing the state of use of the final product. 6 and 7 show an embodiment of the second invention, FIG. 6 is a perspective view showing the main parts, FIG. 7a is a line A-A in FIG. 6, and FIG. It is a sectional view taken along the line BB. DESCRIPTION OF SYMBOLS 1... Binding rope, 2... String-shaped body, 30... Gripping device, 51... Heater, 60... Clamping device,
61a...upper clamp piece, 61b...lower clamp piece.

Claims (1)

[Scope of Claims] 1. Plastic tying ropes are firmly attached to both ends of the plastic tying rope that constitutes the string body of the carrying strap for a shopping bag, and the plastic tying ropes are cut to an appropriate length and then shot. In a method for treating the tip of a plastic tying rope for fixing a plastic string-like body constituting a hanging piece of a carrying strap for a pin bag at right angles; between the tip of the tying rope and the side of the string-like body; When the two are brought into contact with each other via a single heater to melt and join them; the contact by the heater is such that the contact with the side of the string-like body starts before the contact with the tip of the tying rope, and then the A plastic tying rope characterized in that the molten portions formed at the tip of the tying rope and the side portion of the string-like body are joined together, and the joined portions are pinched and pressed from two directions by clamp pieces and brought into contact with each other and cooled and solidified. Tip processing method. 2 A plastic tying rope is firmly attached to both ends of the plastic tying rope that constitutes the string body of the strap for a shopping bag, and the strap is cut to an appropriate length. In a method for processing the end of a plastic tying rope, in which a plastic string-like body constituting a hanging piece is fixed at right angles; a holding device that holds the plastic string-like body linearly along its longitudinal direction; A gripping device in which tongues are arranged alternately on a pair of shafts that are slidable in opposite directions, and grips the end of a plastic binding rope between the tongues; a plurality of heaters are arranged in a row on the lower surface of the plate and the heater; a clamping device consisting of an upper clamp piece and a lower clamp piece arranged in a row on the rotating shaft via an arm; The gripping device is configured to be movable in a perpendicular direction, and is arranged in a position where one side can rub against the side of the string-like body and the other side can come into contact with the end surface of the binding rope; While grasping the end of the rope, move it in a direction perpendicular to the moving direction of the heater, bring the tip of the binding rope into contact with the other side of the heater to melt it, and then touch the side of the string-like body. The clamping device is configured so that it can be moved vertically and horizontally while remaining parallel to the holding device so that it can be transferred to a melting point and bonded; 1. A device for processing the tip of a plastic tying rope, characterized in that the device is configured to pinch and press a joint between the body and the tip of the tying rope. 3. Claim 2, wherein the clamp device is characterized in that, when the joint portion is pressed, the axes of the upper clamp piece and the lower clamp piece are offset from each other in the longitudinal direction of the binding rope. The tip treatment device for the plastic tying rope described.