DE29507643U1 - Load hook - Google Patents

Description

PATENT ATTORNEYS i I **&iacgr;" !Reference number:*·; ;

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DlPL-ING. CON RAD-JOACHIM KÖCH LI NG Note: Hubert Waltermann

Ironware factory and

POBox2069, D-58020 Hagen _r „__.&igr;, _&ogr; _&igr;,_ · _Q j . _r „- _u &ogr; _r

FleyerStraße 135, D-58097 Hagen Gesenkschmiede GmbH & Co

Call{02331)81164 + 85033 Rotloh 4

Fax (O 2331) 84840

Telegrams: Patent Cook Hagen

Accounts: Commerzbank AG, Hagen 3 515095 (8LZ 45040042) D-58802 BaI ve

Sparkasse Hagen 100012043 (bank code 45050001)

Postgiro: Dortmund 5989-460 (bank code 440100 46) ___ ___ _______

11763/95

Serial No.

May 8, 1995

from the

CJK/R

Load hook

The invention relates to a load hook for attachment to a chain or a rope with a hook mouth, which can be closed or released by means of a pawl, the pawl being U-shaped in cross-section and being hinged to the hook shaft, for which purpose the legs of the pawl are held by means of a bolt, preferably a rivet bolt, which passes through the hook shaft, and a leg spring is held on the rivet bolt in the area between the legs and the surface of the hook shaft that is approximately parallel thereto, the leg ends of which are supported on the one hand on the hook shaft and on the other hand on the base of the pawl and by means of which the pawl is forced into the closed position, the pawl being able to be pushed against the spring force into a release position in which it is pivoted towards the hook shaft, the legs of the pawl preferably

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have an extension which, in the closed position, projects from the free end of the hook to beyond the hook shank.

Such load hooks are known in terms of their design and application, for example from DE-26 50 513 C2. In order to ensure the locking function of the pawl, the arrangement of leg springs is provided on the hinge pin, which engage with the rivet bolt or the like with one turn. It has been found that it is necessary to use corresponding springs with high spring stiffness in order to ensure that the pawl is transferred to the closed position as intended when unloaded. The use of correspondingly stiff springs is disadvantageous in that it involves increased effort for the user if he wants to insert a ring link into the hook while pushing the pawl away, for example, or push the hook onto a bolt of a transport container. The same handling problem occurs when the load hook is separated from the corresponding element (ring link or bolt).

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should be released. In addition, due to the high spring stiffness, the number of load changes that the springs can withstand is relatively low, so that the springs have to be replaced after a relatively short period of operation. In order to replace them, it is necessary to remove the bolt, which is usually designed as a rivet bolt. To do this, the rivet head has to be removed using a grinding tool or something similar, which often causes minor or major damage to the leg of the pawl, which is located in the immediate vicinity of the rivet head. This in turn means that after replacing the spring several times and grinding down the bolt head, the leg of the pawl itself is damaged, so that the entire pawl has to be replaced.

Based on this prior art, the invention is based on the object of creating a load hook with a locking pawl of the type described above, which is easy to handle and has a long service life.

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To solve this problem, it is proposed that the legs of the locking pawl are cranked away from each other in the area of the passage of the bolt and that a leg spring with at least two turns enclosing the bolt is arranged in the large free space thus formed between the crank and the hook shaft.

The cranks thus create a relatively large space between the crank and the hook shaft, so that a leg spring with at least two turns enclosing the bolt or even more turns can be inserted into this space. The bolt is of course designed to be longer than the state of the art, so that it can reach through the cranked areas of the legs and rest with its heads (rivet heads) on the outside of the surfaces of the cranks. This means that instead of the previously used springs with high spring stiffness, springs with a lower spring stiffness can be used, since the multiple windings of the springs still provide sufficient

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Spring forces can be applied to ensure that the pawl closes securely. The softer spring characteristics mean that the pawl can be operated with less force. This design also has the advantage that, due to the lower spring stiffness, higher load cycle rates can be achieved, so that replacing the springs due to wear is only required relatively rarely. This in turn also results in a longer service life for the pawl itself, as it cannot be damaged with a grinding tool as often as before.

The design of the crank also has the advantage that the pawl itself is stiffened in the area of its legs, so that the tendency of the legs to bend or deform is counteracted.

In a manner known per se, it is preferably provided that the leg springs arranged on both sides between the hook shaft and the crank are at their ends on the hook shaft

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supporting ends.

In order to achieve further stiffening of the locking pawl, it is also provided that the deformation step of the legs of the locking pawl formed by the cranks extends approximately at right angles to its base, that at least one first bead is pressed out of the leg of the locking pawl, which extends in the area parallel to the longitudinal extension of the leg, which runs next to the hook shaft in the closed position of the locking pawl, and a second bead is pressed out of the leg, which runs approximately transversely to the longitudinal extension of the leg and is directed towards the crank and is cut by the imaginary extension of the first bead, preferably cut in the middle.

This counteracts the deformation of the locking pawl, which often occurs in the usual rough operation in which such load hooks are used. In particular, when such load hooks are pushed onto mounting bolts, the

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are arranged on the side walls of large containers or the like, there is also the risk that the locking pawl will be damaged and deformed by the force exerted when it hits the large container or the bolt. To counteract this, it is also provided that the free end of the hook shaft that protrudes beyond the locking pawl is matched in width to the offsets of the legs of the locking pawl, so that the outer surfaces of the offsets facing away from one another are flush with the outer surfaces of the hook end.

This design, particularly in combination with the beads, which are also in the alignment of the outer surfaces of the cranks and the outer surface of the hook end and also in the outer alignment of the load hook itself, ensures that a flat, continuous contact surface is achieved if the load hook is arranged on the bolt on the container side walls or the like of large containers.

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Waltermann 11763/95

The risk of damage to the pawl is thus largely reduced.

An embodiment of a load hook according to the invention is shown in the drawing and described in more detail below.
It shows:

Fig. 1 shows a safety load hook in side view; Fig. 2 shows the same in front view;

The drawing shows a load hook 1 which can be suitably attached to a steel link chain or a steel cable or even a cable. The load hook has a hook mouth which can be closed or released by means of a locking pawl 2. In the closed position, the locking pawl 2 rests against a projection 3 on the free end of the hook 4 of the load hook 1. Accordingly, the locking pawl 2 can be displaced counterclockwise according to drawing figure 1.

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so that the hook opening is free to allow the insertion of a corresponding ring link or a bolt or the like.

The locking pawl 2 is U-shaped in cross-section and is hinged to the hook shaft 5. The legs 6 of the locking pawl are held by means of a bolt 7, preferably a rivet bolt. The rivet bolt 7 passes through the hook shaft 5 in a corresponding through hole, so that the pivoting mobility of the locking pawl 2 is ensured. A leg spring is held on both sides of the rivet bolt 7 in the area between the legs 6 and the parallel surface of the hook shaft 5, the leg ends of which are supported on the hook shaft 5 on the one hand and on the base of the locking pawl 2 on the other. The locking pawl is pushed into the closed position by means of these springs and can be displaced into a release position against the spring force. The legs 6 of the locking pawl 2 also have an extension 8 which is in

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Closed position, as shown in Fig. 1, from the free hook end 4 to beyond the hook shaft 5.

According to the invention, the legs 6 of the locking pawl 2 are offset away from each other in the area where the bolt 7 passes through. In the large space thus formed between the offset 9 and the hook shaft 5, a leg spring with several turns that surround the bolt 7 is arranged on both sides. The turns of the leg spring are designated 10.

The deformation step 11 of the legs 6 of the locking pawl 2 formed by the offsets 9 runs approximately at right angles to the base of the locking pawl 2. Furthermore, at least one first bead 12 is pressed out of the leg 6 of the locking pawl 2 (it protrudes from the side facing away from the hook shaft 5), which extends in the area parallel to the longitudinal course of the leg, which runs next to the hook shaft 5 in the closed position of the locking pawl 2. Furthermore, a second bead 13 is provided and protrudes outwards from the leg 6.

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deformed, which runs approximately transversely to the longitudinal extension of the leg and is directed towards the crank 11 or 9 and is cut approximately in the middle by the imaginary extension of the first bead 12.

As can be seen in particular from Figure 2, the free end 14 of the hook shaft 5, which projects beyond the pawl 2, is matched in its width to the dimension of the offsets 9 of the legs 6 of the pawl 2, so that the outer surfaces of the offsets 9 facing away from one another are aligned with the outer surfaces of the hook end 14. The protruding beads 13 and 12 as well as the hook material in the lower hook area 4 are approximately in the same alignment.

The selected arrangement makes it possible for springs with multiple turns 10, which have a softer spring characteristic, to be inserted into the space created by the cranks 9. This makes operation easier and increases the service life. In addition, the cranks and the beads 12, 13 ensure that the locking pawl 2 is stiffened overall.

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Due to the aligned contact surfaces, as can be seen in Figure 2, the pawl 2 and its components are protected against lateral impact loads, which can mainly be absorbed by the hook part 4 and the hook end 14.

The invention is not limited to the embodiment but is variable in many ways within the scope of the disclosure.

All new individual and combination features disclosed in the description and/or drawing are considered essential to the invention.

Claims (4)

1. Load hook for attachment to a chain or a rope with a hook mouth which can be closed or released by means of a locking pawl, the locking pawl being U-shaped in cross section and being hinged to the hook shaft, for which purpose the legs of the locking pawl are held by means of a bolt, preferably a rivet bolt, which passes through the hook shaft, and a leg spring is held on the rivet bolt in the area between the legs and the surface of the hook shaft which is approximately parallel thereto, the leg ends of which are supported on the one hand on the hook shaft and on the other hand on the base of the locking pawl and by means of which the locking pawl is forced into the closed position, the locking pawl being able to be pushed against the spring force into a release position in which it is pivoted towards the hook shaft, the legs of the locking pawl preferably having an extension which, in the closed position, projects from the free hook end to beyond the hook shaft, Waltermann 11763/95 -14- characterized in that the legs (6) of the locking pawl (2) are cranked away from one another in the region of the passage of the bolt (7), and a leg spring with at least two turns (10) enclosing the bolt (7) is arranged in the large free space thus formed between the crank (9) and the hook shaft (5). 2. Load hook according to claim 1, characterized in that the leg springs arranged on both sides between the hook shaft (5) and the crank (9) are connected at their ends supported on the hook shaft (5). 3. Load hook according to claim 1 or 2, characterized in that the deformation step (11) of the legs (6) of the locking pawl (2) formed by the cranks (9) extends approximately at right angles to the base thereof, that at least one first bead (12) is pressed out of the leg (6) of the locking pawl (2), which extends in the region parallel to the longitudinal course of the leg, which in the closed position Waltermann 11763/95 -15- the pawl (2) runs next to the hook shaft (5), and a second bead (13) is pressed out of the leg (6), which runs approximately transversely to the longitudinal extension of the leg and is directed towards the crank (3) and is cut by the first bead (12), preferably cut in the middle. 4. Load hook according to one of claims 1 to 3, characterized in that the free end (14) of the hook shaft (5) projecting beyond the pawl (2) is matched in its width to the cranks (9) of the legs (6) of the pawl (2), so that the mutually opposite outer surfaces of the cranks (9) are flush with the outer surfaces of the hook end (14).