Integrally formed swivel hook

Abstract

A swivel hook includes a ring portion defining a hollow inner space and having an external engaging section; a first connecting portion having an upper section rotatably received in the inner space of the ring portion; and a second connecting portion rotatably engaged with the engaging section on the ring portion. The swivel hook is integrally formed by positioning the ring portion in a mold, and then injecting plastic material into the mold to sequentially or simultaneously form the first and the second connecting portion, so that the upper section of the first connecting portion is firmly attached to an inner wall surface of the ring portion, and the second connecting portion is engaged with the engaging section on the ring portion; and then downward pulling the first connecting portion of the initially molded swivel hook to allow it to freely rotate in the inner space of the ring portion.

Description

FIELD OF THE INVENTION

The present invention relates to a swivel hook, and more particularly to a swivel hook that is integrally injection molded in one mold to simultaneously form two swivel connecting portions thereof and can therefore be produced with simplified procedures and shortened time, as well as at lowered mold and assembling costs.

BACKGROUND OF THE INVENTION

There are many different types of connecting and fastening devices that provide convenient and smooth connecting and fastening functions and are therefore widely welcome by consumers. Since these conventional connecting and fastening devices typically have small volume and are easy to use, they are often used on backpacks, knapsacks, fastening belts, key rings, etc. Similar products are successively developed and introduced into markets

FIG. 1 is an exploded perspective view of a conventional swivel hook for connecting and holding two or more different articles together. The conventional swivel hook includes a main body A and a ring-shaped hanger B. The main body A includes an upper truncated-cone pivotal bearing A1, a hook portion A2 downward extended from the pivotal bearing A1, and a locking element A3 provided at one side of the main body A for releasably engaging with the hook section A2 to define a holding space between them. The ring-shaped hanger B is provided at a bottom with a hollow connecting bore B1 for engaging with the pivotal bearing A1. There are a plurality of guide slots B2 provided on an inner surface of the connecting bore B1.

The truncated-cone pivotal bearing A1 has a bottom diametrically larger than a top thereof, allowing the pivotal bearing A1 to be upward extended into the connecting bore B1 from the tapered top. The connecting bore B1 is diametrically slightly smaller than the bottom of the pivotal bearing A1.

Please refer to FIGS. 2 and 3. The conventional swivel hook shown in FIG. 1 requires two separate molds to injection mold the main body A and the ring-shaped hanger B. The separately molded main body A and ring-shaped hanger B are then assembled together by forcing the pivotal bearing A1 of the main body A into the connecting bore B1 at a specific angle, so that the pivotal bearing A1 is extended through the connection hole B1 to abut the larger bottom of the pivotal bearing A1 against an upper end of the connecting bore B1 to hold the pivotal bearing A1 to the ring-shaped hanger B without the risk of separating from the connecting bore B1.

Since two separate molds are required to injection mold the main body A and the ring-shaped hanger B, some disadvantages are existed in the manufacturing of the conventional swivel hook. For instance, increased time is needed to cut the molds, injection mold the main body A and the hanger B, cool and set he injected plastic material, and assemble the molded main body A and hanger B.

Moreover, the pivotal bearing A1 and the connecting bore B1 are often indirectly affected by the conventional manufacturing process and/or defective material to have relatively weak structural strength, and tend to break or become damaged in the process of forcing the pivotal bearing A1 into the connecting bore B1 to assemble the main body A to the hanger B, resulting in difficulty in controlling the stable quality of the finished products.

Further, the pivotal bearing A1 and the hanger B are manually assembled to not only complicate the production but also largely increase the time and labor costs of the swivel hook.

SUMMARY OF THE INVENTION

A primary object of the present invention is to provide an integrally formed swivel hook that can be produced with simplified procedures and shortened time to upgrade the production efficiency thereof.

Another object of the present invention is to provide an integrally formed swivel hook that can be produced at reduced mold and manufacturing costs.

A further object of the present invention is to provide an integrally formed swivel hook that enables reduced assembling cost.

To achieve the above and other objects, the swivel hook the present invention includes a ring portion defining a hollow inner space and being provided on an outer circumferential wall surface with an engaging section; a first connecting portion being injection molded to have a T-shaped upper section engaged with the inner space of the ring portion; and a second connecting portion being injection molded to have two lower inner ends engaged with the engaging section on the ring portion.

In a preferred embodiment of the present invention, the engaging section on the ring portion is a radially outward protruded annular flange or a radially inward annular recess for engaging with the second connecting portion; and the ring portion is made of a metal material, such as copper, iron, aluminum, etc.

The inner space of the ring portion is in the form of a truncated cone having a lower end diametrically slightly larger than an upper end, and defining a downward and outward inclined inner wall surface for the ring portion.

In a most preferred embodiment, the first connecting portion is in the form of a hook-shaped hanger made of a plastic material for an article to connect and lock thereto; and the second connecting portion is in the form of a ring-shaped hanger made of a plastic material.

The swivel hook is integrally formed by positioning the ring portion in a mold, and then injecting plastic material into the mold to sequentially or simultaneously form the first and the second connecting portion, so that the upper section of the first connecting portion is firmly attached to the inclined inner wall surface of the ring portion, and the second connecting portion is engaged with the annular engaging section on the ring portion; and then downward pulling the first connecting portion of the initially molded swivel hook to detach it from the inclined inner wall surface of the ring portion and allow it to freely rotate in the inner space of the ring portion.

BRIEF DESCRIPTION OF THE DRAWINGS

The structure and the technical means adopted by the present invention to achieve the above and other objects can be best understood by referring to the following detailed description of the preferred embodiments and the accompanying drawings, wherein

FIG. 1 is an exploded perspective view of a conventional swivel hook;

FIGS. 2 and 3 schematically show the manner of assembling a main body and a hanger of the conventional swivel hook of FIG. 1;

FIG. 4 is an assembled perspective view of an integrally formed swivel hook according to a preferred embodiment of the present invention with a second connecting portion thereof shown in phantom line;

FIG. 5 shows perspective and vertical sectional views of two embodiments of a ring portion of the swivel hook of the present invention;

FIG. 6 shows the step of forming a first connecting portion of the swivel hook of the present invention in a mold;

FIG. 7 shows the step of forming the second connecting portion of the swivel hook of the present invention in the same one mold;

FIG. 8 is a perspective view of a finished product of the integrally formed swivel hook of the present invention;

FIG. 9 shows one manner of making the first and the second connecting portion of the swivel hook of the present is invention to rotate independently relative to the ring portion; and

FIG. 10 includes two enlarged views of the circled areas in FIGS. 7 and 9, respectively.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Please refer to FIGS. 4 and 5, in which an integrally formed swivel hook according to a preferred embodiment of the present invention is shown. As shown, the integrally formed swivel hook includes a ring portion 1 defining a hollow inner space 11, and being provided on an outer circumferential wall surface with an engaging section 12; a first connecting portion 2 being injection molded to have a T-shaped upper section engaged with the inner space 11 of the ring portion 1; and a second connecting portion 3 being injection molded to have two lower inner ends engaged with the engaging section 12 on the ring portion 1

In the preferred embodiment, the engaging section 12 on the outer wall surface of ring portion 1 may be either a radially protruded annular flange, as shown in the upper part of FIG. 5, or a radially inward annular recess, as shown in the lower part of FIG. 5, for engaging with the second connecting portion 3; and the ring portion 1 may be made of a metal material, such as copper, iron, aluminum, etc.

The inner space 11 of the ring portion 1 is in the form of a truncated cone to have a lower end diametrically slightly larger than an upper end and thereby defines a downward and outward inclined inner wall surface 13 for the ring portion 1.

As can bc seen from FIG. 4, the first connecting portion 2 is in the form of a hook, to which an article could be connected and locked, and is made of a plastic material through injection molding; and the second connecting portion 3 is in the form of a ring-shaped hanger, and is also made of a plastic material through injection molding.

Please refer to FIG. 6. To integrally form the swivel hook of the present invention, first position the ring portion 1 in a mold 4 used to form the swivel hook. Then, inject the plastic material for forming one of the first and the second connecting portion 2, 3 into the mold 4. In the illustrated embodiment of the present invention, the first connecting portion 2 is injection molded prior to the forming of the second connecting portion 3. To form the first connecting portion 2, first inject the plastic material into the inner space 11 of the ring portion 1 to form the substantially T-shaped upper section. The injected plastic material is expanded due to high temperature to adhere to the inclined wall surface 13 at the inner space 11 of the ring portion 1. A lower section below the T-shaped upper section of the first connecting portion 2 is in the form of a hook-shaped hanger. When the injected plastic material is cooled and set, the first connecting portion 2 is molded. Since the cooled plastic material is subject to shrinkage, the molded first connecting portion 2 would naturally tightly contact with the inclined wall surface 13 of the inner space 11.

FIG. 7 shows the forming of the second connecting portion 3 of the swivel hook of the present invention. First, inject the plastic material into a cavity of the mold 4 for molding the second connecting portion 3. The injected plastic material is expanded due to high temperature, causing the plastic material at the two inner ends of the second connecting portion 3 to firmly adhere to the engaging section 12 on the outer wall surface of the ring portion 1. When the plastic material is cooled, the molded second connecting portion 3 is naturally tightly engaged with the engaging section 12 of the ring portion 1. FIG. 8 shows a finished product of the integrally formed swivel hook of the present invention molded in the manner as described above with reference to FIGS. 6 and 7.

There is not particular restriction to the sequence of the above-mentioned injection molding procedures. It is also acceptable to first injection mold the second connecting portion 3, or to injection mold the first and the second connecting portion 2, 3 at the same time.

When the first and the second connecting portion 2, 3 are initially molded, the first connecting portion 2 is firmly attached to the inclined inner wall surface 13 of the ring portion 1. At this point, an operator may hold the first and the second connecting portion 2, 3 with two hands to apply two opposite forces, as indicated by the two arrows in FIG. 9. Alternatively, the operator may hold the second connecting portion 3 in place with one hand, and pulls the first connecting portion 2 downward with another hand. In any one of these manners, the T-shaped upper section of the first connecting portion 2 under the pull is shifted downward in the truncated-cone-shaped inner space 11 toward the diametrically larger lower end, such that the first connecting portion 2 is no longer firmly attached to but is in rotatable contact with the inclined inner wall surface 13 of the ring portion 1. The T-shaped upper section of the first connecting portion 2 is now abutted at a lower horizontal surface on an upper end of the ring portion without the risk of downward moving out of the ring portion 1, and may be freely rotated in the inner space 11 of the ring portion 1 independent of the second connecting portion 3. FIG. 10 shows at an upper and a lower position thereof enlarged views of the circled areas in FIGS. 7 and 9, respectively, to describe the manner of detaching the T-shaped upper section of the first connecting portion 2 from the inclined inner wall surface 13 of the ring portion 1.

In the present invention, the swivel hook is integrally formed by positioning the ring portion 1 in the mold 4, and then subsequently or simultaneously injection molding 1, 1 the first and the second connecting portion 2, 3 using the same mold 4, so that the two connecting portions 2, 3 are respectively engaged with the inner and the outer wall surface of the ring portion 1 at the same time, and then downward pulling the first connecting-portion 2 of the initially molded swivel hook to allow it to rotate freely in the ring portion 1. It is not necessary to cut two molds, and the swivel hook could be completed through simplified and time-shortened manufacturing procedures to largely upgrade the production efficiency and reduce the mold and assembling costs.

The present invention has been described with a preferred embodiment thereof and it is understood that many changes and modifications in the described embodiment can be carried out without departing from the scope and the spirit of the invention that is intended to be limited only by the appended claims.

Claims

1. An integrally formed swivel hook, comprising:

a ring portion defining a hollow inner space and being provided on an outer circumferential wall surface with an engaging section;

a first connecting portion being injection molded to engage an upper section with said inner space of said ring portion; and

a second connecting portion being injection molded to engage with said engaging section on the outer circumferential wall surface of said ring portion.

2. The integrally formed swivel hook as claimed in claim 1, wherein said engaging section is selected from the group consisting of a radially protruded annular flange and a radially inward annular recess.

3. The integrally formed swivel hook as claimed in claim 1, wherein said ring portion is made of a metal material.

4. The integrally formed swivel hook as claimed in claim 1, wherein said inner space of said ring portion is in the form of a truncated cone having a lower end diametrically larger than an upper end of said inner space.

5. The integrally formed swivel hook as claimed in claim 1, wherein said inner space of said ring portion defines a downward and outward inclined inner wall surface for sail ring portion.

6. The integrally formed swivel hook as claimed in claim 1, wherein said first connecting portion is in the form of a hook-shaped hanger, to which an article is connected and locked.

7. The integrally formed swivel hook as claimed in claim 1, wherein said first connecting portion is made of a plastic material.

8. The integrally formed swivel hook as claimed in claim 1, wherein said second connecting portion is in the form of a ring-shaped hanger, to which an article is connected.

9. The integrally formed swivel hook as claimed in claim 1, wherein said second connecting portion is made of a plastic material.