Clamp

Abstract

This application discloses a one-piece, molded, plastic clamp having a pair of side or clamping members joined along one edge by a thin web of the plastic which serves as a hinge. The clamp is molded with the two clamping members arranged at approximately 180.degree., that is, in tandem in the same plane. One of the clamping members has an integral latch finger and the other clamping member has a integral keeper means which engages the latch to lock the clamping members together in clamping or closed position. Means are provided which form an endwise open passageway adjacent the hinge when the clamp is closed, through which a supporting rod can be inserted. The entire clamp is so designed that it can be molded as a complete product in a two-piece mold without the use of cams.

Description

BACKGROUND OF THE INVENTION

This application is related to my application entitled "Molded Garment Clamp" Ser. No. 18,108; Mar. 10, 1970.

The invention relates to a one-piece injection molded plastic clamp for articles. The clamp has a pair of clamping members joined along one edge by a flexible web. The opposite edges of each clamping member are free and when the clamp is closed, serve as article gripping means. In between the free edges and the flexible web or hinge the sides of the clamp are spaced apart and are resiliently deflectable to permit the clamping pressure to be increased by deflecting the sides against their resilient bias. The clamp also includes the latch for holding the clamp in closed position. The clamp, when closed, forms a tunnel or passage opening endwise of the clamp by which the clamp can be mounted on a supporting rod or the like. The clamp is designed to be injection molded as a single part by a simple mold having only two moving parts, since the clamp is designed without reentry portions to prevent release of the clamp from a two-part mold.

The invention provides a small, compact clamp of many uses which may be so economically manufactured that it can be treated as a disposable item. It may be used for clamping almost any type of article including paper, clothing and display items. Because it is molded of plastic it may be safely used in connection with objects which might be injuriously affected by contact with metal, wood or similar materials. It also has no finish coating which could mark or otherwise mar an article on which the clamp is used.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a view of a clamp incorporating this invention in its open position as its appears as removed from the mold;

FIG. 2 is a side elevation view of the clamp illustrated in FIG. 1 showing the clamp in closed position and hung on a support;

FIG. 3 is a plurality of the clamps hung on a typical support;

FIG. 4 illustrates a modified form of the invention as it would appear when removed from the mold;

FIG. 5 is a side elevation view of the clamp shown in FIG. 4;

FIG. 6 illustrates a further modification of the invention showing the clamp as it would appear when removed from the mold;

FIG. 7 is a sectional elevation view taken along the plane VII--VII of FIG. 6; and

FIG. 8 is a view similar to FIG. 7 but showing the clamp in closed position .

Referring specifically to FIG. 1 the clamp 10 consists of a main body 11 having a pair of clamping members 12 and 13 joined along one edge by a flexible web 14 serving as a hinge. In the center of the body is an aperture or opening 15 which is more or less symmetrical about the flexible web 14 and extends into both of the clamping members 12 and 13.

As will be best seen in FIG. 2, the clamping members 12 and 13, intermediate their ends, are arched, whereby these clamping members, when the clamp is closed, are spaced apart at approximately the center of the clamp. The space thereby created between the clamping members is bridged by a latch 16 equipped on its free end with one or more teeth 17 which engage over and lock to one edge or keeper 18 (FIG. 1) of the opening 15. In the particular form of the invention shown in FIGS. 1 and 2 the other end of the latch 16 is integral with the clamping member 13 at the edge of the opening 15 opposite from the keeper 18.

The clamp also has a pair of connectors 20, one on each side of the opening 15. Each of the connectors is symmetrical about the flexible web 14 and incorporates a portion of the flexible web 14 which also serves as a hinge 21 (FIG. 2). On each side of the hinge 21 each of the connectors has a section 22. One of the sections 22 extends into the clamping member 12 and is joined to it by a flexible web or hinge 23. The other of the sections 22 extends into the clamping member 13 and is joined to this member by a flexible web or hinge 23. On one side, each of the connectors 20 forms one side of the opening 18 and along its other side is severed from the clamping members 12 and 13.

When the clamping member 10 is closed, the hinges 21 fold oppositely to the flexible web 14, permitting the sections 22 to double inwardly toward the center of the clamp as shown in FIG. 2. This creates a passage or tunnel 25 opening through the ends of the clamp to receive a support such as the rod 26. As will be seen in FIG. 3, one or more of the clamps 10 can be so mounted on a support and will be held without danger of being disengaged from the support, whether the clamp is open or closed. In many operations this is advantageous because it prevents the clamps from being accidently knocked off the support. An example of a situation in which this is an important factor is a photographic darkroom where the clamps are used to suspend negatives while drying. In this case, the operator is normally operating in very poor light and should a clamp be accidently dislodged he might very well be unable to locate it.

It will be observed from FIG. 1 that when the clamp is in its fully open position the two clamping members 12 and 13 together with the connectors 20 lie basically in a common plane with the latch extending substantially normal to this plane. Thus the entire clamp has no portions which will hang-up on a simple two-part mold when the mold is open. This permits the clamp to be manufactured as a single, integral part more rapidly and with lower cost tooling thus reducing its cost to a fraction of that heretofore possible in devices of this type.

FIGS. 4 and 5 illustrate a modified form of the clamp shown in FIG. 1. In the clamp 10a the side members 12a and 13a are basically the same as side members 12 and 13. However, the central aperture is omitted and a separate small aperture is provided in each side member. The latch 16 is integral with one edge of the aperture 30 in side member 13a and one edge of the aperture 31 in side member 12a serves as the keeper 18. Between the apertures 30 and 31 a single connector 20a is symmetrical about the flexible web 14a. The connector 20a along each edge is severed at 32 from the adjacent body of the side members 12a and 13a. At each end, the connector 20a is joined to one of the side members by a flexible web or hinge 23a. Like the connectors 20, it has a pair of sections 22a joined by a portion 33 of the flexible web 14a. When the clamp 10a is folded to closed position, the connector 20a will fold in the same manner as the connectors 20 to produce an endwise opening tunnel or passage similar to and serving the same purpose as the passage 25.

FIGS. 6, 7 and 8 illustrate a modification of this invention. Clamp 40 has a pair of side members 41 and 42 joined together by a flexible web or hinge 43. A generally central aperture 44 extends into both of the side members 41 and 42 and is more or less symmetrical about the flexible web 43.

FIG. 6 shows the inside face of the side members 41 and 42, these faces being defined as they will be related to each other when the clamp is closed. At the end of the aperture 44 in the side member 42 a latch 45 is integral with the side member 42. A manipulation or finger pad 46 is provided on the free end of the latch and overlies a portion of the opening 44. Teeth 47 are provided on the latch 45. The teeth 47 engage a keeper 48 at the opposite end of the aperture 44. The keeper 48 is integral with the side member 41. To facilitate engagement between the latch and the keeper, the keeper may be equipped with a camming ramp 49 (FIG. 7). The side member 41 may be braced by a reinforcing bead 50 (FIG. 6) aligned with the keeper 48.

Adjacent the flexible web 43, the side member 41 has an inwardly projecting flange 51 and the side member 42 has an inwardly projecting flange 52 (FIG. 7). The web 43 joins the ends of these flanges. As a result of this arrangement it will be seen in FIG. 8 that the side members 41 and 42 are spaced apart when the clamp is closed.

Extending along a portion of each of the sides of the side member 41 is a reinforcing rib 55. The ends of the ribs 55 are spaced both from the flanges 51 and from the free end of the side member. Similar ribs 56 are provided on the side member 42 but spaced inwardly with respect to the edges of the side member offsetting them laterally of the clamp with respect to the reinforcing ribs 55. The height of the ribs 55 and 56 is such that when the clamp is closed they overlap, as is clearly seen in FIG. 8. Thus they create a passageway or tunnel 57 extending endwise through the clamps adjacent the hinge 43. This permits the clamp to be mounted on a rod (not shown) similar to the rod 26 (FIGS. 2 and 3) with the reinforcing ribs 55 and 56 serving the same purpose as the connectors 20 of the clamp 10.

It is important to the invention that the side members between the hinge and the article gripping edges be so shaped that they are spaced apart even when the clamp is fully closed. This spacing permits the necessary deflection of the side members at the latch to permit effective latching and positive article gripping pressure. In all embodiments it is optional whether small teeth, serrations or similar gripping surfaces will be provided on the inner faces of the free ends of the side members. Whether or not such are provided does not change the principles of the invention.

In all of the several embodiments of the invention which have been described, the flexible web or hinge is created by reducing the wall thickness of the plastic. In all cases it is molded of the same plastic as the remainder of the body of the clamp. In all embodiments the side or clamping members are resiliently deflectable within a limited range. This is important to assure both positive engagement between the latch and the keeper and adequate clamping pressure on the articles to effectively grip them. Thus, the plastic material used for the manufacture of this invention must not only be suitable for injection molding, but it must, in a wall thickness of about 0.0625 inch, have significant resistance to deflection yet in a wall thickness of about 0.02 have the characteristic of being both flexible and fatigue resistant.

A number of resinous materials may be used for this product. Resins particularly suitable for the manufacture of this product include polypropylene, polyethylene and certain of the types of nylon. These materials are capable of developing the desired resilient stiffness, that is, capable of some but only limited deflection, and resistance to fatigue when used as a hinge.

In all embodiments the invention must be so designed that the entire product can be manufactured as a single, integral part. This must be accomplished by simple, two-part molds which do not have any cams or movable sections to release any reentry portion of the product.

For this purpose, the design must be such that no part of the clamp is so related to the remainder of the clamp that in one plane it overlies any other portion of the body of the clamp lying in another plane which planes are spaced apart perpendicular to the surfaces of the clamp in such a manner as to create an undercut or reentry condition. In other words, all surfaces must be accessible and withdrawable from each of two mold halves movable perpendicular to the surfaces of the clamp as indicated by the arrows A and B in FIGS. 5 and 7. It will be readily seen from FIG. 5 that this same condition is true for clamp 10 shown in FIG. 1. In cases where slight reentry occurs, such as is the case with the teeth of the latch, the withdrawal of one half of the mold will permit removal of the clamp from the mold because the resilience of the molded part will permit minor deflection of the latch sufficient to effect disengagement of the teeth from the other mold-half.

While a preferred embodiment and several modifications of this invention have been illustrated and described, it will be recognized that other modifications of this invention may be made. Such of these modifications as incorporate the principles of this invention are to be considered as included in the hereinafter appended claims unless these claims, by their language, expressly state otherwise.

Claims

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows.

1. A clamp having a pair of clamping members each having a free edge and joined together along an opposite edge thereof by a flexible web whereby they can be pivoted from an open position in which they are generally aligned in a common plane to a closed position in which their free edges are inwardly pressed toward one another; a latch projecting inwardly of said clamp when closed, one end of said latch being integral with one of said clamping members; there being an opening through the other of said clamping members, one edge of said opening being a keeper interengaging with and securing said latch when said clamp is closed; and flexible bridging means integrally mounted to said clamping members for providing a closed channel between said clamping members and said flexible web, said clamping members, flexible web and latch all being a single integral part in which, when said clamp is fully open with the clamping members generally aligned on opposite sides of the flexible web no portion of the clamp in any plane parallel to that occupied by the clamping members overlaps any other portion of the clamp and the clamp may be molded in a two-piece mold opening and closing in a direction perpendicular to said aligned clamping members.

2. A clamp having a pair of clamping members each having a free edge and joined together along an opposite edge thereof by a flexible web whereby they can be pivoted from an open position in which they are generally aligned in a common plane to a closed position in which their free edges are pressed together, a latch projecting inwardly of said clamp when closed, one end of said latch being integral with one of said clamping members; there being an opening through the other of said clamping members, one edge of said opening being a keeper interengaging with and securing said latch when said clamp is closed; said clamping members, flexible web and latch all being a single integral part in which, when said clamp is fully open with the clamping members generally aligned on opposite sides of the flexible web no portion of the clamp in any plane parallel to that occupied by the clamping members overlaps any other portion of the clamp and the clamp may be molded in a two-piece mold opening and closing in a direction perpendicular to said aligned clamping members; said one clamping member having an aperture therein; said latch projecting from an edge of said aperture and having a finger pad on the end thereof, generally parallel to said one clamping member and overlying said aperture.

3. A clamp as described in claim 2, in which each of said clamping members has a flange projecting away from the plane occupied by said open aligned clamping members and toward said finger pad, said flexible web joining said flanges and being spaced from said plane for holding said clamping members in spaced relationship when said clamp is closed.

4. A clamp as described in claim 3, in which a rib projects inwardly from each of said clamping members, the ends of said ribs being spaced from both said flexible web and said free edges, the rib on one of said clamping members being offset laterally from the rib on the other of said clamping members; the height of said ribs being such that they overlap when said clamp is closed to form a passage extending endwise of the clamp to receive a support therethrough.

5. A clamp having a pair of clamping members each having a free edge and joined together along an opposite edge thereof by a flexible web whereby they can be pivoted from an open position in which they are generally aligned in a common plane to a closed position in which their free edges are pressed together, there being an aperture in one of said clamping members, a latch projecting inwardly of said clamp when closed, one end of said latch being integral with said one clamping member along one side of said aperture; there being an opening through the other of said clamping members, one edge of said opening being a keeper interengaging with and securing said latch when said clamp is closed; said clamping members, flexible web and latch all being a single integral part in which, when said clamp is fully open with the clamping members generally aligned on opposite sides of the flexible web, no portion of the clamp in any plane parallel to that occupied by the clamping members overlaps any other portion of the clamp and the clamp may be molded in a two-piece mold opening and closing in a direction perpendicular to said aligned clamping members, a folding connector being provided, said connector having a pair of sections, one on each side of said flexible web and joined by a portion of said flexible web; each of said sections on the end opposite from said flexible web being pivotally connected to the adjacent clamping member and along each side being severed from the clamping members, the portion of the flexible web joining said sections folding oppositely to that joining the clamping sections with the sections folding into the clamp as it is closed to form a passage extending endwise of the clamp to receive a support therethrough.

6. A clamp comprising: a pair of clamping members joined together by a flexible web whereby they can be pivoted from an open position, in which they are generally aligned in a generally common plane, to a closed position, in which an item can be held between said clamping members; a folding connector being pivotally joined at one end to one of said clamping members and at its other end to the other of said clamping members; said clamping members including an aperture extending between the pivotal connections of said folding connector to said clamping members such that no portion of said clamping members overlie said folding connector when said clamp is in said open position and said clamp can be molded in a two-piece mold.

7. The clamp of claim 6 comprising: said folding connector having a pair of sections, one on each side of said flexible web and being joined by a portion of said flexible web; each of said sections on the end opposite from said flexible web being pivotally connected to the adjacent clamping member and along each side being severed from the clamping members, the portion of the flexible web joining said sections folding oppositely to that joining the clamping sections with the sections folding into the clamp as it is closed to form a passage extending endwise of the clamp to receive a support therethrough.

8. A clamp comprising: a pair of clamping members, each having a free edge, and joined together along an opposite edge thereof by a flexible web whereby they can be pivoted from an open position in which they are generally aligned in a common plane to a closed position in which their free edges are pressed together; a latch integral with one of said clamping members and a latch engaging keeper integral with the other thereof for holding said clamp in a closed position; said clamping members intermediate said flexible web and said free ends being spaced apart and being resiliently deflectable to permit the clamping pressure of the free ends to be increased with said latch locking to said keeper when said clamping members are so deflected.

9. The clamp of claim 8 comprising: one of said latch and keeper including a plurality of teeth spaced transversely of said clamping members and the other of said latch and keeper including teeth engaging means whereby the pressure applied by said clamp when closed can be varied by using different ones of said teeth in conjunction with said teeth engaging means.

10. The clamp of claim 8 in which said clamping member with which said latch is integral includes an aperture therein, said latch extending inwardly from the edge of said aperture.