Cord fastener

Abstract: A cord fastener includes an insert (1) having an inner cord hole (3h) extending laterally therethrough, a shell (11) having an insertion hole for allowing insertion of the insert and having outer cord holes (13) alignable with the inner cord hole (3h) for receiving a cord (S) therethrough, and a coil spring (21) for biasing the insert (1) out of the shell (11), wherein the insert (1) is provided at a lower portion thereof with a provisional retaining claw (5), and the shell (11) has a provisional retainer (15) provided on an inner surface of the insertion hole below the outer cord holes (13) for engaging with the provisional retaining claw (15) in a first state when the inner and outer cord holes are approximately aligned, and has a pusher (16) provided on an inner surface of the insertion hole below the provisional retainer (15) for pressing the provisional retaining claw (5) inward in a second state when the insert (1) is pressed against the force of the coil spring (21) to enter more deeply into the shell (11) than in the first state, thereby causing the provisional retaining claw (5) to adopt a position which avoids subsequent contact with the provisional retainer (15).

Description: This invention relates to a cord fastener for use in adjusting the fastening state or fastening position of a cord of, for example, a tent, knapsack or parka. A cord fastener of this type usually consists of an insert having an inner cord hole, a shell having an insertion hole for insertion of the insert and outer cord holes facing the inner cord hole and communicating with the insertion hole, and a coil spring serving as an energizing member for biasing the insert in the direction of projecting it from the shell, whereby a cord passed through the outer cord holes and the inner cord hole is clamped between the insert and the shell owing to the biasing force of the coil spring, thereby enabling the cord to be maintained in a fastened state and the fastening position thereof to be adjusted. The clamping force of the insert and the shell on the cord is increased by increasing the force of the coil spring. To pass a cord through the outer and inner cord holes of this conventional cord fastener, the insert has to be pressed into the shell against the force of the coil spring and maintained in the depressed state to keep the holes in approximate alignment. Since the worker who inserts the cord therefore has to continue pressing the insert by finger during cord insertion, the efficiency of the operation is poor. Over a prolonged period of such work, the worker is likely to tire and become unable to skilfully press the insert into the shell. This reduces the working efficiency, particularly in the case of a cord fastener with a strong spring. This invention was accomplished to overcome the aforesaid disadvantages and has as its object to provide a cord fastener which does not require the insert to be pressed during cord insertion and thus enables the cord insertion operation to be conducted efficiently even over long work periods. According to the invention, a cord fastener comprises: an insert having an inner cord hole extending laterally therethrough, a shell having an insertion hole for allowing insertion of the insert and having outer cord holes communicating with the insertion hole and alignable with the inner cord hole, and an energizing member provided in the insertion hole for biasing the insert in a direction of projecting the insert from the insertion hole, said cord fastener being characterized in that: the insert is provided at a lower portion thereof with a provisional retaining claw, and the shell has a provisional retainer provided on an inner surface of the insertion hole below the outer cord holes for engaging with the provisional retaining claw in a first state when the inner and outer cord holes are approximately aligned, and has a pusher provided on the inner surface of the insertion hole below the provisional retainer for pressing the provisional retaining claw inward in a second state when the insert is pressed against the force of the energizing member to enter more deeply into the insertion hole than in the first state, thereby causing the provisional retaining claw to adopt a position which avoids subsequent contact with the provisional retainer. In one arrangement, the provisional retaining claw is plastically deformable, opens upward to present a tip which engages with the provisional retainer when in the first state, and is plastically deformed by the pusher when in the second state. In another arrangement, the provisional retaining claw is resiliently deformable, opens upward to present a tip which engages with the provisional retainer when in the first state, and is secured by a catch presented by the insert when in the second state. In yet another arrangement, the provisional retaining claw is resiliently deformable, opens downward to present an intermediate portion which engages with the provisional retainer when in the first state, and further presents a hooked portion which is secured by the insert when in the second state. In all of the arrangements, there may be more than one of each of the provisional retaining claw, the provisional retainer and the pusher. Moreover, in all of the arrangements it will be appreciated that, since the lower portion of the insert is provided with the provisional retaining claw(s) and the inner surface of the shell is formed with the provisional retainer(s), these two members engage to retain the inner cord hole of the insert and the outer cord holes of the shell in approximate alignment, and the work of inserting a cord can therefore be conducted easily without need to keep the insert pressed into the shell by manual manipulation. Once the insertion of the cord is completed, the insert is pressed more deeply into the shell. This causes the provisional retaining claw(s) to be plastically deformed, or secured by the insert, thereby adopting a position which avoids subsequent contact with the provisional retainer(s). As a result, the cord fastener of the invention can then be used in the same manner as an ordinary cord fastener. Three embodiments of this invention will be described, by way of example only, with reference to the accompanying drawings in which:- Figure 1(a) is a plan view of an insert used in a cord fastener that is a first embodiment of the invention; Figure 1(b) is a front view of the insert of Figure 1(a) showing the left half thereof in section; Figure 1(c) is a side view of the insert of Figure 1(a) showing the left half thereof in section; Figure 1(d) is a bottom view of the insert of Figure 1(a); Figure 2(a) is a plan view of a shell used in the first embodiment of the invention cord fastener; Figure 2(b) is a front view of the shell of Figure 2(a) showing the left half thereof in section; Figure 2(c) is a side view of the shell of Figure 2(a) showing the left half thereof in section; Figure 2(d) is a bottom view of the shell of Figure 2(a); Figure 3(a) is a plan view of the first embodiment of the cord fastener in the provisionally retained state; Figure 3(b)is a front view of the cord fastener of Figure 3(a) in the provisionally retained state, showing the left half thereof in section; Figure 3(c)is a side view of the cord fastener of Figure 3(a) in the provisionally retained state, showing the left half thereof in section; Figure 3(d) is a bottom view of the cord fastener of Figure 3(a) in the provisionally retained state; Figure 4(a) is a sectional view of the first embodiment of the cord fastener showing the insert partially inserted into the shell; Figure 4(b) is a sectional view of the cord fastener of Figure 4(a) showing the insert provisionally retained by the shell; Figure 4(c) is a sectional view of the cord fastener of Figure 4(a) showing the insert pushed deeply into the shell; Figure 4(d) is a sectional view of the cord fastener of Figure 4(a) showing a cord clamped by the insert and the shell; Figure 5 is an exploded view, partially in section, of a cord fastener that is a second embodiment of the invention; Figure 6(a) is a sectional view of the cord fastener of Figure 5 showing the insert partially inserted into the shell; Figure 6(b) is a sectional view of the cord fastener of Figure 5 showing the insert provisionally retained by the shell; Figure 6(c) is a sectional view of the cord fastener of Figure 5 showing the insert pushed deeply into the shell; Figure 6(d) is a sectional view of the cord fastener of Figure 5 showing a cord clamped by the insert and the shell; Figure 7 is an exploded view, partially in section, of a cord fastener that is a third embodiment of the invention; Figure 8(a) is a sectional view of the cord fastener of Figure 7 showing the insert partially inserted into the shell; Figure 8(b) is a sectional view of the cord fastener of Figure 7 showing the insert provisionally retained by the shell; Figure 8(c) is a sectional view of the cord fastener of Figure 7 showing the insert pushed deeply into the shell; and Figure 8(d) is a sectional view of the cord fastener of Figure 7 showing a cord clamped by the insert and the shell. Cord fasteners embodying the invention will now be described in detail with reference to the accompanying drawings. Figure 1 to 4 show a cord fastener that is a first embodiment of the invention. The cord fastener comprises an insert 1 formed of synthetic resin to have a head portion 2 which is of elliptical shape in plan view and functions as a stopper, a shaft portion 3, elliptical in plan view but smaller than the head portion 2, which extends downward from the head portion 2, a cylindrical portion 4 which extends downward from the shaft portion 3 in the profile thereof but has shorter lateral length than the shaft portion 3, elastic provisional retaining claws 5, 5 rising from opposite lateral sides of the bottom end of the cylindrical portion 4 and opening outward, and catches 6, 6 extending outward from opposite lateral sides of the top end of the cylindrical portion 4 so as not to collide with provisional retainers 15, 15 of a shell 11 (explained later) and to secure the provisional retaining claws 5, 5 so as not to collide with the provisional retainers 15, 15 (explained later). The shaft portion 3 has a laterally extending inner cord hole 3h, grooves 3d, 3d formed above the inner cord hole 3h for receiving retaining projections 14, 14 of the shell 11 (explained later), and an annular groove 3g formed in its bottom surface located inside the cylindrical portion 4 for receiving and fixing the position of a coil spring (explained later). The shell 11, shown in Figure 2, is formed of synthetic resin to have the same elliptical shape in plan view as that of the head portion 2. It has an elliptical insertion hole 12 for insertion of the shaft portion 3 and is provided at opposite lateral sides thereof with outwardly flared outer cord holes 13, 13 alignable with the inner cord hole 3h. The upper end of the inner surface of the insertion hole 12 is formed at locations opposite the grooves 3d, 3d with the retaining projections 14, 14 for engaging with the grooves 3d, 3d to prevent the insert 1 from falling out of the insertion hole 12. The inner surface of the insertion hole 12 below the outer cord holes 13, 13 is formed at locations opposite the provisional retaining claws 5, 5 with the provisional retainers 15, 15 for engagement with the tips of the provisional retaining claws 5, 5. The inner surface of the insertion hole 12 below the provisional retainers 15, 15 is formed at locations opposite the provisional retaining claws 5, 5 with pushers 16, 16 for pressing the provisional retaining claws 5, 5 inward so as not to collide with the provisional retainers 15, 15. The floor of the shell 11 is formed at the center thereof with a locator protuberance 17 for positioning the other end of the coil spring 21 and at locations near the pushers 16, 16 with die extraction holes 18, 18, which are holes remaining after extraction of the die portions for forming the provisional retainers 15, 15. Figure 3 shows the cord fastener according to the first embodiment of the invention as assembled into the provisionally retained state. Figure 3(a) is a plan view, Figure 3(b) a front view with the left half shown in section, Figure 3(c) a right side view with the left half in section, and Figure 3(d) a bottom view. The front view of Figure 3(b) and the right side view of Figure 3(c) are laterally symmetrical, the rear view (not shown) is the same as the front view, and the left side view (not shown) is the same as the right side view. As shown in Figure 3, a coil spring 21 is inserted in the insertion hole 12 between the insert 1 and the floor of the shell 11 as an energizing member which biases the insert 1 in the direction of projecting it from the insertion hole 12. Figures 4(a), 4(b), 4(c) and 4(d) show the operation of the first embodiment of the cord fastener. The symbol S in these figures designates a cord. The assembly of this cord fastener, the passing of a cord therethrough and the clamping of the cord thereby will now be explained. As shown in Figure 1(b), in the initial state of the insert 1, the tips of the provisional retaining claws 5, 5 are not engaged with the catches 6, 6 but open outward by their own elasticity (resiliency). The coil spring 21 is inserted into the shell 11 so that its other end (i.e., lower end) is located around the locator protuberance 17. The insert 1 is then positioned over the insertion hole 12 of the shell 11 with its cylindrical portion 4 facing downward, whereafter the cylindrical portion 4 and the shaft portion 3 are pushed into the insertion hole 12 so that the one end (i.e., upper end) of the coil spring 21 is inserted into the cylindrical portion 4. As they move inward, the cylindrical portion 4 and the shaft portion 3 apply outward pressure on the retaining projections 14, 14. This pressure elastically deforms the shell and enables the cylindrical portion 4 and the shaft portion 3 to enter the insertion hole 12. The retaining projections 14, 14 pass along the exteriors of the cylindrical portion 4 and the shaft portion 3 and enter the inner cord hole 3h. This is the state shown in Figure 4(a). In this state, the insert 1 cannot be extracted from the insertion hole 12 unless the shell 11 is elastically deformed by application of pressure in opposite lateral directions. At this time, the one end of the coil spring 21 is located in the groove 3g. When the insert 1 in the state shown in Figure 4(a) is pressed further into the insertion hole 12 against the force of the coil spring 21, the provisional retaining claws 5, 5 first flex inward under pressure from the provisional retainers 15, 15 and then, when they have passed the provisional retainers 15, 15 and the inner and outer cord holes 3h, 13, 13 are approximately aligned (this being called the "first state"), they open outward owing to their elasticity so that their tips move under the provisional retainers 15, 15. In this state, if the inward pressure on the insert 1 is released, the provisional retaining claws 5, 5 engage with the provisional retainers 15, 15 to establish a provisionally retained state in which the inner and outer cord holes 3h, 13, 13 are maintained approximately aligned, as shown in Figure 4(b). A cord S can therefore be passed through the inner and outer holes 3h, 13, 13. The passage of the cord S through the inner and outer holes 3h, 13, 13 is easy to achieve because the outer cord holes 13, 13 are flared outward (tapered inward) so that the surface of the outer cord hole 13 into which the cord S is inserted guides the cord S into the inner cord hole 3h. When the insert 1 in the state shown in Figure 4(b) is pressed further into the insertion hole 12 against the force of the coil spring 21 until the head portion 2 strikes on the shell 11 as shown in Figure 4(c) (this being called the "second state"), the provisional retaining claws 5, 5 are flexed inward by pressure from the pushers 16, 16 so that the tips of the provisional retaining claws 5, 5 engage with the catches 6, 6. In this state, the provisional retaining claws 5, 5 are prevented from collision with the provisional retainers 15, 15. In this state, if the inward pressure on the insert 1 is released, the insert 1 is pushed upward by the biasing force of the coil spring 21. As a result, the cord S is clamped by the insert 1 and the shell 11 as shown in Figure 4(d). Since the portions of the shell 11 at the upper side of the outer cord holes 13, 13 are formed as sharp edges, the biasing force of the coil spring 21 on the insert 1 concentrates at these edge portions of the shell 11 when the cord S is clamped between the insert 1 and the shell 11. When the cord S is clamped by the insert 1 and the shell 11, the cylindrical portion 4 hides the interior of the shell 11 from view through the outer cord holes 13, 13. As is clear from the forgoing, the cord fastener according to the first embodiment of the invention consists of only three components, the insert 1, the shell 11 and the coil spring 21. Owing to the small number of components, it can be manufactured at low cost. Moreover, the assembly of the cord fastener is simple, only requiring insertion of the insert 1 into the shell 11 after insertion of the coil spring 21 into the shell 11. Since the retaining projections 14, 14 engage with the insert 1 when the insert 1 is inserted into the shell 11, the insert 1 and the shell 11 are safe from separation even when no cord S has been passed through the cord fastener. In the first state, when the provisional retaining claws 5, 5 are engaged with the provisional retainers 15, 15, the inner and outer cord holes 3h, 13, 13 are in approximate alignment so that the insert 1 need not be pressed inward against the force of the coil spring 21 while the cord S is being passed through these holes. The work of inserting cords into cord fasteners can therefore be conducted with good efficiency even over long work periods. The passage of the cord S through the inner and outer holes 3h, 13, 13 is easy to perform because the outer cord holes 13, 13 are flared outward so that the surface of the outer cord hole 13 into which the cord S is inserted guides the cord S into the inner cord hole 3h. Since the cylindrical portion 4 of the insert 1 hides the interior of the shell 11 from view through the outer cord holes 13, 13, foreign matter is prevented from entering the shell 11 through the outer cord holes 13, 13 during use. This reduces the possibility of operational problems. Figure 5 is an exploded view of a cord fastener that is a second embodiment of the invention, and Figures 6(a), 6(b), 6(c) and 6(d) show the operation thereof. Portions the same as or similar to those of the first embodiment of Figures 1 to 4 are assigned the same reference symbols as those of the first embodiment and will not be described further. Figure 5 shows the left halves of the insert and the shell in section. The points of difference between the insert 1 of the second embodiment and that of the first embodiment are that the provisional retaining claws 5, 5 are directed downward from the shaft portion 3, that the tips of the provisional retaining claws 5, 5 are bent toward the cylindrical portion 4 and are provided with hooked portions 5a, 5a for engagement with the catches 6, 6, and that the catches 6, 6 are constituted by the bottom end of the cylindrical portion 4. The other portions of the insert 1 of the second embodiment are the same as the other portions of the insert 1 of the first embodiment. The assembly of the cord fastener, the passing of a cord therethrough and the clamping of the cord thereby, shown in Figures 6(a) to 6(d), are substantially the same as those of the first embodiment and will not be described further. The second embodiment provides the same effects as the first. Figure 7 is an exploded view of a cord fastener that is a third embodiment of the invention, and Figures 8(a), 8(b), 8(c) and 8(d) show the operation thereof. Portions the same as or similar to those in Figures 1 to 6 are assigned the same reference symbols as those in these Figures and will not be described further. Figure 7 shows the left halves of the insert and the shell in section. The points of difference between the insert 1 of the third embodiment and that of the first embodiment are that it is formed of a resin such as ABS resin enabling plastic deformation of the provisional retaining claws 5, 5 when they are subjected to more than a prescribed amount of stress and that the catches 6, 6 are omitted. The other portions of the insert 1 of the third embodiment are the same as the other portions of the insert 1 of the first embodiment. The assembly of this cord fastener, the passing of a cord therethrough and the clamping of the cord thereby will now be explained. In the initial state of the insert 1, the tips of the provisional retaining claws 5, 5 open outward. After the coil spring 21 has been inserted into the shell 11, the shaft portion 3 of the insert 1 is inserted therein and pressed inward. The cylindrical portion 4 and the shaft portion 3 press the retaining projections 14, 14 outward as they move inward until the shaft portion 3 is partially inserted in the insertion hole 12 as shown in Figure 8(a). When the insert 1 is pressed further into the insertion hole 12 against the force of the coil spring 21, the tips of the provisional retaining claws 5, 5 are first flexed slightly inward by pressure from the provisional retainers 15, 15 and then, when they have passed the provisional retainers 15, 15 and the inner and outer cord holes 3h, 13, 13 are approximately aligned (the first state), the provisional retaining claws 5, 5 flex back to their original state and their tips move under the provisional retainers 15, 15. Although the provisional retaining claws 5, 5 are plastically deformable, they are nevertheless able to return to their original state because the amount of inward flexing is slight at this time and the elastic limit is not exceeded. When the inward pressure on the insert 1 is released, the tips of the provisional retaining claws 5, 5 engage with the provisional retainers 15, 15 to establish the provisionally retained state shown in Figure 8(b). When the insert 1 in the first state shown in Figure 8(b) is pressed further into the insertion hole 12 against the force of the coil spring 21 until the head portion 2 strikes on the shell 11 as shown in Figure 8(c) (the second state), the provisional retaining claws 5, 5 are pushed strongly inward and deformed by pressure from the pushers 16, 16. Since the provisional retaining claws 5, 5 are made of plastically deformable resin, they deform inward and do not restore to their original state when the pressure exerted thereon exceeds the elastic limit of the resin. The provisional retaining claws 5, 5 thus stay in the state with their tips pointing upward. When the inward pressure on the insert 1 is released and the insert 1 is pushed upward by the biasing force of the coil spring 21, the insert 1 rises without colliding with the provisional retainers 15, 15. As a result, a cord S can be clamped by the insert 1 and the shell 11 as shown in Figure 8(d). The third embodiment of the cord fastener therefore provides the same effects as the first. Since the insert 1 of the third embodiment does not require catches for securing the provisional retaining claws, it is of simple shape and can be formed with a mold of simple configuration using a small amount of resin. The insert 1 of this embodiment can therefore be produced at low cost. As the cord fastener according to this invention consists of only three components, the insert, shell and energizing member, it can be inexpensively manufactured. Moreover, since the inner cord hole and the outer cord holes are in approximate alignment in the first state when the provisional retaining claws are engaged with the provisional retainers, the insert need not be continuously pressed inward against the force of the coil spring while the cord S is being passed through the cord holes. The work of inserting cords into cord fasteners can therefore be conducted with good efficiency even over long work periods. In addition, the cord fastener can be conferred with the same functions as an ordinary cord fastener after passage of the cord through the cord holes simply by strongly pressing the insert more deeply into the shell. Another advantage of the cord fastener according to the invention is that the portions of the outer cord holes where the cord is not present are covered by the cylindrical portion of the insert, thereby preventing invasion of foreign matter into the shell through the outer cord holes during use and thus precluding operational problems.

Claims: A cord fastener comprising: an insert (1) having an inner cord hole (3h) extending laterally therethrough, a shell (11) having an insertion hole (12) for allowing insertion of the insert (1) and having outer cord holes (13, 13) communicating with the insertion hole (12) and alignable with the inner cord hole (3h), and an energizing member (21) provided in the insertion hole (12) for biasing the insert (1) in a direction of projecting the insert (1) from the insertion hole (12), said cord fastener being characterized in that: the insert (1) is provided at a lower portion thereof with a provisional retaining claw (5), and the shell (11) has a provisional retainer (15) provided on an inner surface of the insertion hole (12) below the outer cord holes (13, 13) for engaging with the provisional retaining claw (5) in a first state when the inner and outer cord holes are approximately aligned, and has a pusher (16) provided on the inner surface of the insertion hole (12) below the provisional retainer (15) for pressing the provisional retaining claw (5) inward in a second state when the insert (1) is pressed against the force of the energizing member (21) to enter more deeply into the insertion hole (12) than in the first state, thereby causing the provisional retaining claw (5) to adopt a position which avoids subsequent contact with the provisional retainer (15). A cord fastener according to claim 1, characterised in that the provisional retaining claw (5) is plastically deformable, opens upward to present a tip which engages with the provisional retainer (15) when in the first state, and is plastically deformed by the pusher (16) when in the second state. A cord fastener according to claim 1, characterised in that the provisional retaining claw (5) is resiliently deformable, opens upward to present a tip which engages with the provisional retainer (15) when in the first state, and is secured by a catch (6) presented by the insert (1) when in the second state. A cord fastener according to claim 1, characterised in that the provisional retaining claw (5) is resiliently deformable, opens downward to present an intermediate portion which engages with the provisional retainer (15) when in the first state, and further presents a hooked portion (5a) which is secured by the insert (1) when in the second state. A cord fastener according to any preceding claim, characterised in that there is more than one of each of the provisional retaining claw (5), the provisional retainer (15) and the pusher (6). A cord fastener according to any preceding claim, characterised in that the lower portion of the insert (1) is formed with a cylindrical portion (4) which receives one end of the energizing member (21) and hides the intericr of the shell (11) from view through the outer cord holes (13, 13).

Inventors: IKEDA YASUHIKO, IKEDA, YASUHIKO
Applicants: NIFCO INC, NIFCO INC.
Application year: 1997
Main classification: F16G11
IPC codes: F16G11, A44B99