Mechanical connection between strip sections of a clamp

(42) Date of commencement of the patent: 15. 9.1992 (45) Date of issue: 25. 5.1993 (62) Elimination from application No: 4098/83

<td>(30) Priority:</td><td>(73) Patent owner:</td>

<td>3.12.1982 US 446503 claims.</td><td>HANS OETIKER AG MACHINE AND APPARATUS FACTORY CH-8810 HQRGEN (CH).</td>

<td>(56) Documents:</td><td></td>

<td>FR-PS2516181</td><td></td>

(54) MECHANICAL CONNECTION BETWEEN TAPE SECTIONS OF A CLAMP (57) The invention relates to the mechanical connection between two opposing tape sections (14, 16) which form part of a clamp. For this purpose, at least two hooks (13, 12) are provided in the inner band section (14). A hook is a cold-formed hook and serves as a support hook (13). The other hook serves as a guide and support hook (112); he has an abutment surface (112a, 112b) to the force (handle on. The guide and support hook (112) first guides the inner and outer band portions (14, 16) relative to each other and receives circumferentially directed forces until it is assisted by the support hook (13) in the load transfer. In the outer band portion (16) openings (15, 115) for the positive engagement of the hooks (13, 112) are provided.

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AT 396 003

MR 0078318

AT396 003B

The invention relates to a mechanical connection between two opposing overlapping band portions, which form part of a clamp which is firmly engageable over an object to be fastened, in which at least two outwardly extending hooks in the inner band portion for positive engagement in the outer band portion engage openings provided.

There are already various embodiments of hose clamps are known which comprise a clamping band, which consists for example of a flat strip, the free ends can be mechanically connected to each other, wherein a ring-like clamping device is formed, the z. B. by tightening a so-called Oetiker ear can be tightened.

It must be basically differentiated between terminals whose free ends are permanently connected to each other before attaching the terminals, and the so-called open terminals, the free ends are only connected to each other when the terminals are arranged around the object to be tightened. The first hose clamp group, to which the terminals count, whose open ends are previously connected to each other, for example by spot welding or a rivet-like connection, and the z. B. in U.S. Patent 3,286,314, similar to the hose clamps of U.S. Patent Nos. 2,614,304 and 3,082,498 (Fig. 1 and 2) are attached, d. H. they must be pushed axially over the object to be fastened before the so-called Oetiker ear is stretched when the hose clamp is completely installed. However, an axial mounting of the hose clamp is then practically impracticable, if, for example, in assembly line work a terminal has been arranged, for example, on a cuff, and where then the incorrectly mounted terminal must be cut and removed, and a spare terminal with the same dimensions subsequently instead of the faulty mounted hose clamp must be properly installed. If no spare clamp of the same dimensions and of the open-ended type is available, which clamp can simply be wrapped around the component to be fastened and subsequently closed and tensioned, it would be necessary releasing various previously assembled components and then sliding the replacement clamp axially, which procedure, especially in the case of assembly line as used in particular in the manufacture of automobiles, would be associated with unsustainable workload and costs. The same problem would of course arise if, instead of a faulty mounted terminal this terminal was ever forgotten.

To solve this problem, various proposals have been made in the direction of open-ended clamps, which can be attached to the object to be fastened at any time by placing them around the object. So z. B. From AT-PS 378 838 an open clamp known which has at least two hooks for connecting their ends on the inner band portion, which engage in corresponding openings in the outer band portion. In this case, a hook is a guide hook which can pass through the corresponding recess and is preferably tongue-shaped; it serves to guide the inner and outer band sections in the initial phase of the tensioning process. Another hook is formed by cold deformation support hook having an end face which can accommodate the forces transmitted in the circumferential direction on the support hooks. (The force is transmitted through an edge of the corresponding opening on the face.)

The disadvantage of the known terminal is that the guide hook can take no or at least no large forces. Excessive force on the guide hook bends back so that the clamp opens. The force acting in the circumferential direction of the clamp is thus absorbed almost exclusively by the support hooks. In order to obtain terminals that can absorb sufficiently high forces, it is necessary in terminals according to the prior art to provide at least two support hooks, as shown in the figures of AT-PS 378 838.

It is an object of the present invention, the connection between the band portions of a terminal in such a way that - with the same capacity of the terminal - less hooks and corresponding openings are necessary, so that the production of the terminal is easier and cheaper, or that with the same number of hooks and corresponding openings the terminal is more stable.

This object is achieved in a mechanical connection of the type mentioned, characterized that the two hooks are of different construction with successive functions, wherein a hook is a cold-formed hook, which has a supportive function, when it engages in a corresponding opening, and the other hook is a hook with an abutment surface for force engagement, which is located along its end facing away from the free end of the inner band section and which has both leadership and support function, the other hook first guides the inner and outer band portions towards each other and receives circumferentially directed forces, until he is supported by the cold-formed a hook in the Kraftübemahme.

So it is the other hook constructed by using a support-like surface that it serves both as a support hook and as a guide hook. This has the great advantage that relatively large forces in the circumferential direction can be absorbed by the guide and support hooks until the end of attaching the clamp, where then the cold-formed support hooks can perform a support function.

The stability of the mechanical connection is increased by the use of the cold-formed hook in combination with the guide and support hook, because the latter can absorb forces in the circumferential direction even after the attachment of the clamp. This can therefore lead to terminals where no longer two

-2AT396 003B cold-formed support hooks are necessary.

The actual invention thus consists in the combination of the cold-formed support hook with the guide and support hooks.

According to one embodiment of the invention, the combined guiding and supporting hook is a cold-formed hook with the abutment surface for force engagement along its end remote from the free end of the inner band portion.

According to another embodiment, the combined guiding and supporting hook is a nose-like hook extruded from the inner band section, which extends substantially in the circumferential direction of the clamp, the abutment surface being formed for force engagement by the obliquely upward trailing edge of the nose-like hook extends opposite the free end of the inner band portion.

With reference to FIG. 1 to 4, the invention is explained in more detail: 1 is a plan view of an embodiment of a clamp according to the invention, wherein the inner band portion is provided with two support hooks as well as with an additional cold-formed hook with both guiding and supporting function, Fig. 2 is a side view of a portion of the clamp of FIG. 1, Fig. 3 is a plan view of a part of another embodiment of a clamp according to the invention, in which the inner band portion is provided with two support hooks and another hook with both guiding and supporting function, and Fig. 4 is a side view of the part of the terminal of FIG. Third

In the drawings, like parts in different figures are given the same reference numerals. According to FIGS. 1 and 2, the mechanical connection is made by a cold-formed hook (112) with guide and support function. This hook (112) is formed from the strip material by cold forming in such a way that it is separated from the inner band portion (14) only along the engagement and abutment surfaces (112a) and (112b), which in plan view (Fig. 1) are substantially V-shaped. Along its remaining contour, the cold-formed hook (112) with the inner band portion (14) forms a whole. The mechanical connection is supplemented by two support hooks (13) provided on the inner band section (14). All hooks (112, 13) are suitable for engagement with openings (15, 115) provided in the outer band section (16).

In order to allow clamping of the clamp on an object to be fastened using a clamping tool, the outer and the inner band portion (16, 14) each with an abutment for tool engagement in the form of cold-formed extruded sections (24) and (25) of at least approximately semicircular cross section. The extruded portion (24) for tool engagement in the outer band portion (16) is substantially semi-cylindrical with transverse, acting as abutment surfaces cuts, with its cylinder walls in the axial direction with the outer band portion (16) form a whole. The cold-formed extruded portion (25) for engaging the inner band portion (14) has, on the contrary, only one cut (25a) serving as a tool engaging abutment surface, forming a whole with the inner band portion (14) substantially over its remaining contour. The outer band portion (16) is also provided between its extruded portion (24) and the openings (15) with an opening (27) having a width such that the extruded portion (25) for tool engagement of the inner band portion (14 ) can extend therethrough. Moreover, the inner and outer squeezed portions (25) and (24) have complementary shapes such that the squeezed portion (25) of the inner band portion (14) under the squeezed portion (24) of the outer band portion (16) during clamping of the clamp can slide by means of the clamping tool.

In order to allow some sort of pre-assembly, in the inner band portion (14) adjacent the extruded portion (25) is provided another outwardly extending hook (28) which may also extend through the aperture (27) and provide a pre-assembly, when it comes into contact with the end surface (27a) of the opening (27). The hook (28) can be a simply punched out hook of nose-like configuration.

As the thinner and harder plastic tubing materials become increasingly important in avoiding any step or discontinuity along the inner, object contacting surfaces of the clamp, the clamp is provided with further means for eliminating each step. These devices have a tongue-like extension (31) at the free end of the inner band portion (14) which is adapted to engage in a tongue-receiving channel formed by a step (33) and two longitudinal cuts (34) and (34 '). ) (Fig. 3) which prevents the formation of the channel by pressing out the central band portion (35) relative to the lateral band portions (36) remaining on either side of the cuts (34) and (34 ') (FIG. 1) permit, is formed. When assembled, the tongue-like extension (31) engages the channel so that each step is effectively eliminated. Of course, the means for eliminating each stage or discontinuity can also be modified.

In the embodiment of Figs. 3 and 4, the guide and support hook (112) of the embodiment of Figs. 1 and 2 is replaced by a guide and support hook (212) which has a nose-shaped configuration from which wall material is extruded extending generally in the circumferential direction, being provided with an abutment surface (212a), similar to the nose (4) in U.S. Patent 3,286,314. The opening corresponding to the guide and support hook (212) is designated (215)

-3AT396 003B