METHOD OF ATTACHING PARTS OF A SEPARABLE BOTTOM END ASSEMBLY TO A CONTINUOUS SLIDE FASTENER CHAIN

Abstract: In a method of attaching parts of a separable bottom end assembly to a continuous slide fastener chain, a box or insertion pin (8b), (8a), in the shape of a channel, of a separable bottom end assembly is threaded onto one of longitudinally spaced successive element-free portions (4) of one longitudinal edge of a continuous slide fastener stringer (2) in an edgewise direction while the one element-free portion (4) is kept stationary at an attaching station (A) on a substantially horizontal path of the fastener stringer (2) as the latter is at rest. The thus threaded pin (8a), (8b) is then fixedly secured to the one element-free portion (4) as compressed into a final shape therearound.

Description: The present invention relates to a method of attaching a box or insertion pin of a channel shape to one longitudinal edge of a continuous slide fastener stringer of a separable slide fastener having a separable bottom end assembly at one of longitudinally spaced successive element-free portions thereof said method comprising the steps of moving the fastener stringer longitudinally along a substantially horizontal path; partially twisting the fastener stringer (2) through an angle of 90° so as to take an upright posture with the one longitudinal edge thereof directed downwardly; temporarily terminating the movement of the fastener stringer when one of the successive element-free portions arrives at an attaching station; threading the channel-shaped pin onto said one element-free portion of the one longitudinal edge of the fastener stringer; and fixedly securing the threaded channel-shaped pin to said one element-free portion by compressing said pin into a final shape around said one longitudinal edge of the fastener stringer while the latter is at rest. A method of this type is disclosed in DE-A-2 112 076. This prior art method is carried out with an apparatus as reillustrated here in Figure 4, in which an insertion pin 8b and a box pin 8a (with a box 8c), both in the shape of a channel, of a separable bottom end assembly are threaded onto the respective leading element-free end portions 4a, 4a of a pair of uncoupled continuous slide fastener stringers 2, 2 in an endwise direction, i. e. longitudinally from one of opposite end openings of the respective pin, as shown in Figures 5A and 6A. Each pin 8a, 8b is then fixedly secured to the element-free end portions 4a as compressed into a final shape (Figures 5B and 6B) therearound by means of a respective holder or punch B, C (Figure 4). A common problem with this prior art method is that because of smallness of the end openings of the pin, it is difficult or impossible to mount the pin correctly in a required position on the leading element-free end portion, especially if the latter is an objectionably bulged or otherwise deformed condition. Further, this inaccurate and insufficient threading would be a cause for possible misoperations in various subsequent progressive finishing stages of the production, thus resulting in inadequate quality products. US-A-3 863 321 discloses a method of automatically attaching top stops to a continuous slide fastener stringer for a non-separable slide fastener, in which the top stops are attached to an element-free portion of the inner longitudinal edge of the slide fastener stringer in a direction transverse to this longitudinal edge, while the slide fastener stringer is at rest. However, it has to be considered that in this known method the mating slide fastener stringers are arranged in a common horizontal plane and the confronting inner longitudinal edges thereof are locally squeezed out of this common plane from below by a wedge-shaped finger until these longitudinal edges are arranged in two planes perpendicular to the main plane of the two tapes. Thereupon, a top stop is fixed each at the diverted longitudinal edges of the two tapes by means of a punch means which is vertically movably disposed above the stringer path. The present seeks to provide a method of attaching parts of a separable bottom end assembly to a continous slide fastener chain easily with precision, thus making various subsequent progressive finishing stages of the production free from misoperations due to inaccurate mounting of the parts. Accordingly, the present invention is particularly suitable for automatic production of separable slide fasteners. According to the invention a method satisfying these requirements is characterized by threading said pin onto said one element-free stringer, by approaching said stringer from the direction perpendicular to said longitudinal edge while the fastener stringer is at rest and kept in a state of tension; said threading step being carried out at the attaching station where a pair of holders or clamps are disposed below the stringer path and are movable vertically toward and away from the respective downwardly looking longitudinal edges of the fastener stringers, each fastener stringer being kept in its state of tension by means of upstream and downstream grippers. Many other advantages, features and additional objects of the present invention will become manifest to those versed in the art upon making reference to the detailed description and the accompanying drawings in which certain preferred embodiments incorporating the principles of the present invention are shown by way of illustrative example. Figure 1A is a fragmentary perspective view showing the manner in which a box or insertion pin is attached to a continuous fastener stringer at one element-free portion contiguous to a leading or cut end of the stringer; Figure 1B is a view similar to Figure 1A, showing the manner is which a box or insertion pin is attached to a continuous fastener stringer at one element-free portion remote from a leading or cut end of the stringer; Figure 2A is a fragmentary cross-sectional view showing the manner is which the pin is threaded onto the inner longitudinal edge of the fastener stringer by a holder or clamp; Figure 2B is a view similar to Figure 2A, showing the manner in which the threaded pin is fixedly secured to the inner longitudinal edge of the fastener stringer as compressed by the holder or clamp; Figure 3A is a fragmentary plan view of a pair of uncoupled continuous slide fastener stringers to which a box pin and an insertion pin have been attached respectively; Figure 3B is a side elevational view of a half of Figure 3A, showing a twisted portion of each fastener stringer; Figure 4 is a fragmentary perspective view of a prior art apparatus for automatically finishing separable slide fasteners; Figures 5A and 5B illustrate the manner in which an insertion pin is attached to the fastener stringer by the prior art apparatus of Figure 4; and Figures 6A and 6B illustrate the manner in which a box pin with a box is attached to the fastener stringer by the prior art apparatus of Figure 4. Figure 3A shows a pair of uncoupled slide fastener stringers 2, 2 being moved longitudinally along a substantialy horizontal straight path through an attaching station A (of a separable-slide-fastener finishing apparatus) where an insertion pin 8b and a box pin 8a are attached to inner longitudinal edges of the fastener stringers 2, 2, respectively, in a manner described below as each stringer 2 is partially twisted through an angle of 90 o so as to assume an upright posture with its inner longitudinal edge directed downwardly as shown in Figure 3B. Each fastener stringer 2 has longitudinally spaced element-free portions 4 devoid of coupling elements 5. The movement of each fastener stringer 2 is temporarily terminated when one of the successive element-free portions 4 arrives at the attaching station A where a pair of holdersor clamps 6, 6 are disposed below the stringer path and are movable vertically toward and away from the respective inner longitudinal edges of the two fastener stringers 2, 2. Meanwhile, each clamp 6 pre-clamps a box or insertion pin 8a, 8b of a channel shape delivered from a chute 10 onto an auxiliary support 7, as shown in Figures 1B and 2A, at which time the pin 8a, 8b is open widely with its opposite side walls diverging upwardly. Upon termination of the movement of the fastener stringers 2, 2, each clamp 6 holding the respective pin 8a, 8b is raised from the solid-line position to the phantom-line position in Figures 1B and 2A until the pin 8a, 8b is threaded onto the inner longitudinal edge 4a of the one element-free portion 4 in an edgewise direction from a longitudinal upward opening of the channel (of the pin 8a, 8b), i.e. in the direction perpendicular to the longitudinal edge of upright fastener stringer 2. At that time, since the longitudinal upward opening of its channel is open widely, each pin 8a, 8b can be threaded over the element-free inner longitudinal edge 4a in a proper posture to a required extent without difficulty even if the latter is in an objectionably bulged or otherwise damaged condition. Then the thus threaded pin 8a, 8b is compressed into a final shape about the element-free longitudinal edge 4a as a pair of parts of each clamp 6 are angularly moved relative to one another about a pivot 9 from the position of dash-and-one-dot lines to the position of solid lines in Figure 2B. As a result, each pin 8a, 8b has been fixedly secured to the longitudinal edge 4a of the one element-free portion of the respective fastener stringer 2 precisely at a required position in a proper posture. During the threading and compressing, each fastener stringer 2 is kept in a state of tension as gripped by upstream and downstream grippers 11 (only upstream gripper is illustrated). Finally, each clamp 6 opens to release the respective attached pin 8a, 8b and returns to the initial or lower position (dash-and-two-dot lines) in Figure 2B. The resulting fastener stringers 2, 2 are further moved to the following station where a subsequent finishing process, such as cutting or pairing, may take place. In the embodiment of Figures 1A, 3A and 3B, each pin 8a, 8b is attached to the respective fastener stringer 2 at one element-free portion 4 that is remote from the leading or cut end of the fastener stringer 2. Alternatively, the pin 8a, 8b may be attached to the fastener stringer 4 at one element-free portion 4 that is contiguous to the leading or cut end of the fastener stringer 2, as shown in Figure 1A; that is, the attaching takes place after a preceding piece of the fastener stringer of the individual slide fastener length (not shown) has been cut from the continuous fastener stringer 2 across that one element-free portion 4.

Claims: A method of attaching a box or insertion pin (8a), (8b) of a channel shape to one longitudinal edge of a continuous slide fastener stringer (2) of a separable slide fastener having a separable bottom end assembly at one of longitudinally spaced successive element-free portions (4) thereof, said method comprising the steps of: moving the fastener stringer (2) longitudinally along a substantially horizontal path; partially twisting the fastener stringer (2) through an angle of 90° so as to take an upright posture with the one longitudinal edge thereof directed downwardly; temporarily terminating the movement of the fastener stringer (2) when one of the successive element-free portions (4) arrives at an attaching station (A); threading the channel-shaped pin (8a), (8b) onto said one element-free portion (4) of the one longitudinal edge of the fastener stringer (2); and fixedly securing the threaded channel-shaped pin (8a), (8b) to said one element-free portion (4) by compressing said pin (8a), (8b) into a final shape around said one longitudinal edge of the fastener stringer (2) while the latter is at rest; characterized by threading said pin (8a), (8b) onto said one element-free portion (4) of the one longitudinal edge of the fastener stringer (2), by approaching said stringer (2) from the direction perpendicular to said longitudinal edge while the fastener stringer is at rest and kept in a state of tension; said threading step being carried out at the attaching station (A) where a pair of holders or clamps (6) are disposed below the stringer path and are movable vertically toward and away from the respective downwardly looking longitudinal edges of the fastener stringers, each fastener stringer being kept in its state of tension by means of upstream and downstream grippers. A method according to claim 1, wherein said one element-free portion (4) is disposed contiguously to a leading end of the fastener stringer (2). A method according to claim 1, wherein said one element-free portion (4) is disposed remotely from a leading end of the fastener stringer (2).

Inventors: SODENO, TOSHIAKI
Applicants: YOSHIDA KOGYO K.K.
Application year: 1985
Main classification: A44B19
IPC codes: A44B19