GB2254368A

GB2254368A - Swivel snap hook

Info

Publication number: GB2254368A
Application number: GB9206919A
Authority: GB
Inventors: Kazuo Ida
Original assignee: Yoshida Kogyo KK
Current assignee: YKK Corp
Priority date: 1991-04-04
Filing date: 1992-03-30
Publication date: 1992-10-07
Anticipated expiration: 2012-03-30
Also published as: GB2254368B; GB9206919D0

Abstract

A swivel snap hook of small number of component parts which provides efficient assembly operations to secure a relative rotation between a snap hook body (1) and a ring member (2). In a connecting portion of the snap hook body (1), a neck portion (14) of the small diameter and a contractible columnar expanded portion (15) of the larger diameter are connected in series with each other. In a locking portion (27) of the ring member (2), a second engaging hole (26-2) of approximately the same shape as the expanded portion (15) is provided above a step portion (26-3) in series with a small diameter portion side of a first engaging hole (26-1) of approximately truncated cone of approximately the same length as the neck portion (14) of the snap hook body (1), the large diameter portion whose size is about equal to the expanded portion (15) in normal state, and the small diameter portion whose size is about equal to the expanded portion (15) in the contracted state. Then, the expanded portion (15) is pushed through the first engaging hole (26-1) and accommodated firmly in the second engaging hole (26-2). <IMAGE>

Description

Title of the Invention Swivel Snan hook Background of the Invention 1. Field of the Invention This invention relates to an swivel snap hook made of synthetic resins or metals, which may be used in bags and pouches of all kinds.

2. Prior Art There have heretofore been proposed and in practice used variolas snap hooks in which a hooked body and a ring member rotate relatively, regardless of being made of metals or synthetic resins.

however, the conventional snap hooks have been accompanied by attaching members, such as locking means for rotatably combining the snap hook body and the ring member each other, so that the number of component parts and the number of assembly processes have been increased to lead to high production cost. More particularly, the metallic snap hook have not only required the use of a number of component parts and led to high cost but also been difficult to be colored thereon, so that it has been considered to provide poor fashionableness and to be unsuitable for portmanteanx and shoulder bags.

In view of foregoing problems, the snap hook made of the synthetic resin, for example in JP,S63-29124 (Publication of Japanese patent application), is disclosed. It disclosed that an expanded portion of the approximately truncated cone having an axial split groove is formed through the neck portion integral with the upper part of the snap hook body. It also disclosed that the connecting portion between the ring member and the snap hook is provided with the thickness about equal to the length of the neck portion. The expanded portion is provided with a through hole which is insertable with the diameter at contracted state, and the expanded portion of the snap hook body is inserted into the through hole of the ring member and the both are connected to be relatively rotated about the axial center thereof.According to this composition, it is intended for the inexpensive and light snap hook to decrease the attaching members such as locking means so as to reduce the number of the component parts.

However, the snap hook disclosed in the aforementioned publication has mortal defects that the expanded portion of the snap hook is exposed being projected in the connecting portion between the snap hook body and the ring member to provide the poor fashionableness like the conventional ones. Moreover, the diameter of the expanded portion may be forcedly contracted with a compressive force applied from the outside thereto to disengage the expanded portion easily from the through hole of the ring member so as to separate the snap hook body and the ring member.

Also, it is possible that the through hole is one stepped hole with the large diameter portion and the small diameter portion provided via the step portion and the expanded portion of the truncated cone is inserted from the hole of the large diameter portion into the hole of the small diameter portion while reducing the diameter and accommodated in the hole of the large diameter portion. The expanded portion is prevented from exposing outwardly to provide excellent fashionableness, but there is produced a clearance between the expanded portion of the truncated cone and the inner face of the hole of the large diameter, so that if a pin type object is inserted into the ciearance,the diameter of the expanded portion is easily reduced to disengage the expanded portion from the hole of the small diameter to become structurally defective.Furthermore, the dust is easy to invade into the clearance between the expanded portion and the hole, so that the dust clogs the clearance between the bottom of the expanded portion of the truncated cone and the step portion of the two stepped holes. Thus the snap hook has a considerably important defect that it is impossible to provide the relative rotation between the snap hook body and the ring member.

For the swivel snap hook disclosed in the above publication, it is necessary to set the diameter of through hole as small as possible and to set the diameter of the expanded portion of the swivel snap hook as big as possible, in order to prevent the expanded portion from disengaging from the through hole when it receives a heavy load while being used. To fulfil this condition, the expanded portion has to be set to be substantially contractible while the diameter of the neck portion must be set to be as big as possible. Then, these arrangements produce little difference in the diameters of the expanded portion and of the neck portion, so that the engagement of the expanded portion with the through hole of the ring member becomes rather weak, and in combination with the big contraction, the expanded portion becomes easy to disengage from the through hole.This trouble makes this invention's object of preventing the expanded portion from disengaging from the through hole of the ring member unattainable.

Thus, the conventional snap hook has the expanded portion with bigger diameter and the neck portion with the smaller diameter, and the engaging area of the expanded portion with the through hole becomes wider while the diameter of the through hole is made to be a little wider.

However, the diameter of the expanded portion is relatively wider comparing to that of the through hole in this structure, and the diameter of the neck portion becomes relatively small. At the time of assembling, the expanded portion has to be inserted to the through hole forcedly, which makes the neck portion get broken and produces a clearance between the through hole and the neck portion.

The clearance inclines the neck portion toward one side of the through hole, so that the expanded portion becomes easy to disengage from the through hole though there exists a wide engaging area between the expanded portion and the neck portion.

SummarY of the Invention The object of this invention is to provide a snap hook which facilitates excellent fashionableness in addition to reduction of component parts, secures the relative rotation between a hook body and a ring member by preventing the invasion of dust, and provides a connected construction for connecting the snap hook body and the ring member firmly.

To accomplish this object, the composition of this invention provides an swivel snap hook which comprises a hooked and swivel hook body having an arm to prevent disengagement in an opening thereof and an expanded portion of the contractible diameter projected through a neck portion upwardly, and a ring member having a locking portion for engaging with the expanded portion which is attached to an end of a belt means and the like, wherein the snap hook body is connected with the ring member to permit relative rotation, and wherein the expanded portion of the snap hook body is formed as a columnar body and the locking portion of the ring member is a locking hole which includes a first engaging hole of an approximately truncated cone having the length about equal to the length of the neck portion of the snap hook body, the large diameter portion whose diameter is about equal to the diameter of the columnar body in the normal state and the small diameter portion whose diameter is about equal to the diameter of the columnar body in the contracted state, and a second engaging hole being concentrically formed through a step portion on the small diameter side of the first engaging hole.

And more preferable result is expected when a ring shaped projection with the diameter smaller than the expanded portion on and around the outer surface of the neck portion.

In the operation for assembling the snap hook body and the ring member after they are respectively formed separately, if the columnar expanded portion of the snap hook body is pushed into the first engaging hole of the truncated cone in the ring member, the diameter of the expanded portion is gradually reduced in accordance with pushing it along the inner surface if truncated cone in the first engaging hole and finally passed through the small diameter portion of the first engaging hole to return it to the normal state, so that it is firmly accommodated in the second engaging hole of the large diameter to finish up the assembly.

In the connecting portion of the assembled snap hook, the neck portion of the snap hook body goes through the first engaging hole of the ring member, and the bottom of the columnar expanded portion is accommodated firmly in the inner surface of the second engaging hole while being put on the step portion of the locking hole.

The expanded portion of the snap hook is prevented from exposure, and at the same time, there is produced no-clearance between the expanded portion and the second engaging hole of the ring member, so that the dust is prevented from invading and blocking the bottom of the expanded portion and the step portion of the ring member to secure the relative rotation between the snap hook body and the ring member.

Once the expanded portion is engaged with the second engaging hole, it is difficult to reduce the diameter of the expanded portion from the outside so as to secure the connection between the snap hook body and the ring member.

When the neck portion of the snap hook body has the ring shaped projection on and around its outer surface, any horizontal movement or inclination of the neck portion is restricted inside of the smaller diameter of the first engaging hole by the projection. The bottom of the expanded portion does not disengage from the step portion of the engaging hole even though the diameter of the small diameter portion of the first engaging hole is set to be wide to some extent, while the connection between the snap hook body and the ring member is kept firmly, and moreover, the inclination of the neck portion inside the second engaging hole is decreased.

Consequently, the snap hook can not only be readily and inexpensively produced and efficiently assembled from less number of component parts, but also provide excellent fashionableness, secure the relative rotation between the snap hook body and the ring member by preventing the dust from invation therebetween, and produce the connecting structure which firmly connects the snap hook body and the ring member.

The above and other advantages of this invention will become more apparent in the following description and the accompanying drawings wherein a preferred embodiment of this invention is clearly shown.

Brief Description of the Drawings Fig. 1 is a front view of an swivel snap hook for illustrating one embodiment of this invention; Fig. 2 is a sectional view taken on line III-III in Fig. 1; Fig. 3 is a sectional view taken on line II-II in Fig. 1; Fig. 4 is a bottom view of a ring member of other embodiment when a locking member is rotated by 90 degrees; Fig. 5 is a sectional view taken on IV-IV of the connecting portion in Fig. 4.; Fig. 6 is a front view of a hook body of other embodiment of this invention; Fig. 7 is a side view of a hook body in Fig. 6; Description of the Preferred Embodiment Now, this invention is illustrated in detail referring to the drawings.

A snap hook of this invention comprises a ring member to which an end of a belt and the like is attached and a hooked snap hook body having an expanded portion projected from a neck portion upwardly and a disengagement preventing arm in an opening of the hook body, wherein the expanded portion of the hook body is rotatably engaged to be integrated with a locking portion of the ring member.

As shown in Fig. 1 to Fig. 5, a numeral 1 is a hooked body of the snap hook made of a synthetic resin material, which comprises a head portion 11, a hook portion 12 extending from this head portion 11 downwardly, and a disengagement preventing arm 13 for blockading an opening of the hook portion 12 with resilience thereof, wherein these portions are integrally formed.

The head portion 11, as shown in Fig. 1 and Fig. 2, comprises a neck portion 14 and a columnar expanded portion 15 connected to a tip side of the neck portion 14 and is divided with split grooves 11-1 cut off crosswise from the top side thereof to four divided pieces 11-2, 11-2. The disengagement preventing arm 13 is integrally formed from a base 12-1 of the hook portion 12 toward the tip 12-2 of the hook portion 12 and the tip 13-1 of the disengagement preventing arm 13 is locked with the inner surface of the tip 12-2 of the hook portion 12.

In an embodiment shown in drawings, 2 is a rectangular ring member to which an end of a belt is attached, which comprises a horizontally extended main body 21, a pair of legs 22, 23 having engaging holes 22-1, 23-1 extending in parallel at a right angle from both ends of the main body 21 and formed to be opposite to each other at free ends of the legs22, 23 and an elongated locking member 24 of which both ends 24-1, 24-1 of a shaft are rotatably engaged in the engaing holes 22-1, 23-1 of the legs 22, 23. All of the main body 21, legs 23, 24, and the locking member 24 may be also formed integrally to provide a rectangular ring member.

The main body 21 is formed to be thicker than each of the legs 22, 23. A body 25 of the locking member 24 has a thicker main portion, thinner ribs 25-1, 25-1, formed up and down from the main portion, and flanges 25-2, 25-2, formed on both ends of the main portion, and the both ends 24-1, 24-1, of the shaft of the locking member 24 which are respectively projected from the flanges 25-2, 25-2. In a longitudinal center position of main portion, a cylindrical portion 26 expanding in the horizontal direction is formed and a first engaging hole 26-1 of approximately truncated cone is formed at a lower position in the vertical direction of the cylindrical portion 26 at its center position. In the upper side of the small diameter portion of the first engaging hole 26-], a cylindrical second engaging hole 26-2 having a diameter about equal to the diameter of the large diameter portion of the truncated cone is concentrically formed through a step portion 26-3. And a locking hole 27 according to this invention is composed of the first and second engaging holes 26-1, 26-2.

The first engaging hole 26-1 is formed in the approximately truncated cone shown clearly in Fig. 4 and Fig. 5, and the depth of the first engaging hole 26-1 is set at the length about equal to the length of the neck portion 14 formed in the head portion 11 of the snap hook body 1. The diameter of the small portion of the truncated cone is set at the size equal to the diameter of the contracted state of the expanded portion to deform the expanded portion 15 resiliently which is formed in the head portion 11, and the diameter of the large diameter portionis also set at a size slightly larger than the diameter of the expanded portion 15 in the nomal state to provide a slight clearance therebetween.In this embodiment, the first engaging hole 26-1 is not formed as a truncated cone along the whole depth thereof, but it is formed as a truncated cone only in the desired depth and the remainder is formed at the small diameter of the cylindrical portion 26 and opened at the step portion 26-3. In this design, when the snap hook is used, the sufficient strength to receive the load applied to the snap hook is secured and the invasion of the dust from the lower part of the first engaging hole 26-1 is prevented.

The second engaging hole 26-2 is formed in a cylindrical hole, as shown clearly in Fig. 4 and Fig. 5, and the depth of the second engaging hole 26-2 is set at the smaller size than the columnar expanded portion 15 which is formed in the head portion 11 of the of the snap hook body 1. The diameter of the second engaging hole 26-2 is set at the size about equal to the diameter of the expanded portion 15 in the normal state. In this structure, when the expanded portion 15 of the snap hook body 1 is engaged with the second engaging hole 26-2, the cylindrical'second engaging hole 26-2 and the columnar expanded portion 15 are engaged with each other to provide an only slight clearance therebetween, so that the invasion of the dust from the upper part of the second engaging hole 26-2 is completely prevented.The expanded portion 15 is completely accommodated in the second engaging hole 26-2 and the upper part thereof is not projected therefrom outwardly. The slight clearance is produced between the expanded portion 15 and the second engaging hole 26-2, so that even when the expanded portion 15 shall be forcedly disengaged from the second engaging hole 26-2, the diameter of the expanded portion 15 is hardly reduced by the external force so as to prevent the expanded portion 15 from disengaging easily from the ring member 2.

The upper surface of the step portion 26-3 is, as shown in Fig. 4 and Fig. 5, inclined slightly downward from the central portion toward the periphery. Consequently, even when the step portion 26-3 is resiliently deformed with the load applied thereto in the snap hook in use, the diameter of the opening of the step portion 26-3 is prevented from becoming larger than the diameter of the opening in the non-loaded, so that the expanded portion 15 is prevented from disengaging from the first engaging hole 26-1. Of course, the upper surface of the step portion 26-3 may be formed as the horizontal surface.

In this structure, the expanded portion 15 of each divided piece 11-2, 11-2 of the snap hook body 1 is pushed into the first engaging hole 26-1 of the ring member 2 by use of a resilient force of the each divided piece 11-2, 11-2 of the head portion 11 while reducing the diameter thereof. Then, when the neck portion 14 is inserted to the first engaging hole 26-1 and the expanded portion 15 is accommodated firmly in the second engaging hole 26-2, the bottom of the expanded portion 15 is interengaged with the upper surface of the step portion 26-3, so that the expanded portion is connected to the ring member 2.

Thus, the diameter of the neck portion 14 is set at the size slightly smaller than the diameter of the small cylindrical hole 26-1 in the first engaging hole 26-1 of the ring member 2, and the diameter of the expanded portion 15 is set at the size almost the same as the diameter of the slight clearance between the second engaging hole 26-2 and the neck portion, so that the snap hook body 1 connected to the ring member secures smooth rotation about the axis of the neck portion 14 with respect to the ring member 2.

Moreover, in this embodiment, the locking member 4 of the ring member 2 may be rotated about pivotal axes of free ends of both right and left legs 22, 23, so that the snap hook body 1 may be rotated not only about the axis of the neck portion 14, but also about shaft portions 24-1, 24-1 of the locking member 24, so as to permit two directional rotation against the ring member 2.

Accordingly, in a hanging belt removable bag and the like, one end of a belt having one by one snap hook on both ends is attached to one end of a bag and the other end of the belt is attached to the other end of the bag, so that even when the belt has been twisted and the ring member 2 is rotated about the axis of the neck portion 14 against the snap hook body 1, the snap hook is prevented from disengaging from the bag by returning the belt from being twisted immediately. Also, since the snap hook body 1 may be rotated, even when the large load is applied to the snap hook body 1 in the direction inclined at acertain angle with respect to a plane including both leg portions 22, 23 of the ring member 2, the load escapes by rotation and the neck portion 14 is prevented from being damaged.Even when the hanging belt is accommodated in the bag, the snap hook fits the shape of the bag and the baggages in the bag by rotating and prevents itself from protruding outwardly in the bag.

Fig. 6 and Fig. 7 show the other typical embodiment of this invention. A ring shaped projection 14-1 is formed on the outer surface of the neck portion 14. The outer diameter of this projection 14-1 is slightly smaller than that of the expanded portion 15.

By forming the projection 14-1, any horizontal movement or inclination of the neck portion 14 inside of the small diameter of the first engaging hole 26-1 is restricted. Even though the diameter of the small diameter portion of the first engaging hole 26-1 is set to be wider to some extent, the bottom of the expanded portion 15 does not disengage from the step portion 26-3 of the engaging hole 27. And at the same time, the inclination of the neck portion 14 is decreased, so that the neck portion 14 is not expected to get broken, and the connection between the snap hook body 1 and the ring member 2 is kept firmly, while the inclination of the neck portion 14 inside the first engaging hole 26-1 is decreased.

The main body 21, both legs 22, 23 of the ring member 2 and the locking member 24 are integrally formed at the state that the pivot shaft portions 24-1, 24-1 of the locking member 24 are respectively interengaging with engaging holes 22-1, 23-1 of the both legs 22, 23 by use of a set of metal mold at one process.

Thus, to form the ring member 2 at one process, a metal mold member, not shown in the drawings, is provided with a hollow cylindrical projection having a s-shape of the same size to the engaging hole 22-1 of one leg 22. And a hollow portion of the same size to the pivot shaft portion 24-1 of the locking member 24 is used as one member of a molding metal to mold one pivot shaft portion 24-1 of the locking member 24 in the hollow portion, and at the same time, to mold the engaging hole 22-1 with the shape of the projection. Then, the hollow cylindrical projection is projected with the thickness of the leg 22 of the ring member 2. The engaging hole 23-1 of the other leg 23 of the ring member 2 and the other pivot shaft portion 24-1 of the locking member 24 are also formed by use of the like metal mold member.

Thus, when the ring member 2 is formed in one process, the legs 22, 23 of the ring member 2 and the pivot shaft portions 24-1, 24-1 of the locking member 24 are separated by the projections of the metal mold members. Accordingly, in spite of the simultaneous formation, the locking member 24 may be rotated against the legs 22, 23. Also, the snap hook is composed of three parts, namely, the ring member 2 formed integrally of the main body 21 and both legs 22, 23, the locking member 24, and the snap hook body 1. Ilowever, the snap hook may be easily assembled in only the operation that the head portion 11 of the snap hook body 1 is pushed into the first engaging hole 26-1, so as to provide easy and inexpensive assembly operations.

The snap hook body 1 and the ring member 2 are respectively formed separately. A cavity for the snap body 1 is formed at the state that the tip 13-1 of the lower side of the disengagement prevention arm 13 is separated from the tip 12-2 of the hook portion 12 outwardly.

The disengagement preventing arm 13 is bent laterally after being molded, and set to contact the outer surface of the tip 13-1 to the inner surface of the tip 12-2 of the hook portion 12. Thus, the resilient force of the disengagement preventing arm 13 is increased to push the tip 13-1 thereof strongly to the inner surface of the tip 12-2 of the hook portion 12.

The above-mentioned embodiment has been illustrated with respect to the snap hook made of synthetic resin, however the each part of the snap hook according to this invention may be formed by use of diecasts and the like, so that it may be produced from metal material also and an various changes in the form, size, and minor details of structure may be made within the scope of the claims of this invention.

According to this invention, a connection structure of a snap hook body and a ring member comprises an interengaged construction of a locking hole having a first engaging hole of an approximately truncated cone on a ring side and a columnar second engaging hole of a large diameter connected with the small diameter portion of the first engaging hole, and a neck port in and a contractible columnar expanded portion which are respectively engaged with the first and second engaging holes and formed in the snap hook body. And the expanded portion is almost completely accommodated in the second engaging hole without producing a clearance, so as to promote the fashonableness of the snap hook and to prevent it from reducing the diameter thereof from the outside. Therefore, the expanded portion may be prevented from readily disengaging from the first engaging hole of the ring member.And the snap hook body and the ring member are prevented from producing the clearance between the expanded portion and the ring member. And the dust is completely prevented from ivnasion therebetween from the outside, so that the it is prevented from blocking between the bottom of the columnar expanded portion and the step portion of two stepped hole to permit the relative rotation between the snap hook body and the ring member without procuding any trouble.

In case of providing a ring shaped projection with a diameter which is smaller than that of the expanded portion on the outer surface of the neck portion, the horizontal movement or inclination of the neck portion is resticted even when the diameter of'the small diameter portion of the first engaging hole is set to be wider to some extent. So, it becomes not probable that the snap hook body disengages from the ring member, and also it becomes possible that the snap hook body is attached to the ring member easily without breaking the neck portion.

With this invention, the number of the component parts is decreased and the low cost and high efficiency in composing work is achieved. Furthermore, it brings more fashionableness, and secures the relative rotation of the snap hook body and the ring member by preventing the dust from invasion. An advanced swivel snap hook with connecting structure which enables firm connection of the snap hook body l and the ring member without probability of breaking the neck portion.

Claims

What is claimed:

1. An swivel hook comprising a hooked snap hook body (1) having a disengagement preventing arm (13) in an opening and an expanded portion (15) thereof and a ring member (2) having a locking portion (27) for engaging with said expanded portion (15) and being attached to an end of a belt and the like, being characterized by:: an expanded portion (15) formed as a columnar body with a contractible diameter and being projected through a neck portion (14) upwardly, and said locking portion (27) of said ring member (2) having a locking hole (26) which includes a first engaging hole (26-1) of an approximately truncated cone having a length about equal to the neck portion (14) of said snap hook body (1), a large diameter portion about equal to the diameter of the columnar body in the normal state and a small diameter portion about equal to the diameter of the columnar body in the contracted state, and a second engaging hole (26-2) being concentrically formed through a step portion (26-3) on the small diameter side of the first engaging hole (26-1), wherein said snap hook body (1) is connected with said ring member (2) to permit a relative rotation therebetween.

2. An swivel snap hook according to claim 1, wherein a ring shaped projection (14-1) with the diameter smaller than that of said expanded portion (15) is provided on and around the outer surface of said neck portion (14).

3. An swivel snap hook according to claim 1, wherein said ring member (2) is provided with a body integrally formed of a main body (21) and two legs (22, 23), and a locking member (24) having pivot shaft portions (24-1, 24-1) and flanges (25-2, 25-2) on the both ends.

whereby said locking member (24) is rotatably engaged with said legs (22, 23) of said body (21).

4. An swivel snap hook according to claim 1, wherein an upper surface of said step portion (26-3) is inclined slightly downward from the central portion toward the periphery.