GB2174784A

GB2174784A - Chain shackle

Info

Publication number: GB2174784A
Application number: GB08610991A
Authority: GB
Inventors: Hans Dalferth; Hans Bauer
Original assignee: RUD Kettenfabrik Rieger und Dietz GmbH and Co KG
Current assignee: RUD Kettenfabrik Rieger und Dietz GmbH and Co KG
Priority date: 1985-05-07
Filing date: 1986-05-06
Publication date: 1986-11-12
Also published as: AT390830B; GB8610991D0; DE3516800C1; ATA122686A

Abstract

In a chain shackle with shackle parts (1, 2) connected releasably to one another, oval chain links (7, 8) suspended in the shackle are to be protected against clanking. To achieve this object, the chain shackle is equipped with elastic buffers (9, 10) which face the rounded portions of the chain links suspended in the shackle and which consist of rubber or plastic. The buffers are appropriately designed as anti-clanking webs. <IMAGE>

Description

SPECIFICATION Chain shackle The invention retates to a chain shackle for link chains, with shackle parts connected releasably to one another and with anti-clanking means counteracting the clanking of oval chain links suspended in the shackle.

In a chain shackle of the abovementioned type, described in German Utility Model Application G 84 35 342.2, the anti-clanking means consist of metal parts which are connected by means of clamping or welding to a bolt forming a supporting and locking element. The outlay in terms of production for supporting and locking elements of this type is comparatively high. This proves unsatisfactory, because chain shackles are mass-produced articles. It has also been shown that, under unfavourable conditions, the known chain shackles do not with the desired reliability prevent the suspended oval links from clanking, consequently causing damage.

The object on which the invention is based is to improve a chain shackle of the type in question, so that, whilst being simpler to produce, it at the same time reliably prevents damage as a result of clanking. According to the invention, this object is achieved because the anti-clanking means are designed as elastic buffers made of rubber or plastic which face the rounded portion of the respective chain links suspended.

The chain shackle according to the invention offers the advantage that the elastic buffers can be shaped and fastened in one operation by being cast or moulded on in a mould. A considerable bond is obtained simply because the projections are cast on; however, the strength of the connection is further increased significantly by anchoring the buffers to the respective shackle part carrying them. Surprisingly, the anti-clanking effect of the buffers is increased considerably as a result of their elasticity.

In a chain shackle with two essentially U-shaped shackle halves, each having an inner leg and an outer leg; with a bolt supporting the mutually facing sides of the inner legs in the closing position of the shackle, with at least one detent spring arranged in at least one retaining groove in the bolt, and with two projections forming the anti-clanking means, as it is described in the abovementioned Utility Model specification, it proves to be especially advantageous if the elastic buffers form anticlanking webs provided with extensions engaging into anchoring grooves which serve for anchoring them and are made annular and which are arranged at a distance from one another in the region of the bolt ends.

Because of the use of preferably additional extensions which fill the bottom of the retaining groove for the detent spring and which surround the bolt in the manner of barrel hoops, it is possible to exert a favourable influence on the spring characteristic of the detent springs.

The invention is explained in detail below with reference to several exemplary embodiments illustrated in the accompanying drawings. In the draw ings Figure 1 shows a plan view of a chain shackle; Figure 2 shows a section through the chain shackle according to Figure 1; Figure 3 shows a section through the supporting and locking element of the chain shackle according to Figures 1 and 2; Figure 4 shows a plan view of the supporting and locking element according to Figure 3; Figure 5 shows a Section along the line V-V in Figure 3; Figure 6 shows a section along the line VI-VI in Figure 3, and Figure 7 shows a detail of an anchoring groove.

In Figures 1 and 2, 1 and 2 designate as a whole two shackle halves of a chain shackle which are connected releasably to one another and which each have an outer leg 3 and an inner leg 4 connected to one another by means of holding teeth.

A supporting and locking element, designed as a bolt 5 and equipped with detent springs 6 on the bolt periphery, serves for locking the shackle halves 1 and 2 in the closing position and for supporting the mutually facing sides of the inner legs 4.

The ends of two chain links 7 and 8 forming chain strands are suspended in the shackle halves 1 and 2. It goes without saying that, for example, a connecting bracket of a component of any type can also take the place of one of the chain links 7 and 8. To prevent the possibility of the chain links 7 and 8 slanting when the chain is stowed, and prevent them from clanking in the slanted position when a pull is exerted on the chain once again, the bolt 5 is provided with projections which are designed as elastic anti-clanking webs 9 and 10 made of rubber or plastic and which are bonded at least to parts of the periphery of the metal bolt 5. The bond is obtained by introducing bolt 5, together with the detent springs 6, into a mould, in which hardening rubber or plastic is subsequently cast round it. It has proved especially advantageous to use a polyurethane elastomer as a casting resin.

The Shore hardness A of the anti-clanking webs 9, 10 should be of the order of 40 to 90. To guarantee sufficient strength of the connection between the bolt 5 and the elastic anti-clanking webs 9, 10, the latter are provided with extensions 11 which surround the bolt 5 in the manner of octopus arms, as shown in detail in Figures 3 to 7.

Figures 3, 5 and 6 show that the bolt 5 is provided with a retaining groove 12 for the detent spring 6, and with two annular anchoring grooves 13 and 14 for the extensions 11. The anchoring grooves 13 and 14 are preferably undercut (see Figure 7) and are filled with the material used to make the anti-clanking webs 9 and 10, thus producing upper and lower plastic bridges which surround the bolt 5 and connect the anti-clanking webs 9 and 10 to one another, and which guarantee secure anchoring of the anti-clanking webs 9, 10 to the bolt 5.

The material used to make the anti-clanking webs 9, 10 also fills the bottom of the retaining groove 12, thus forming an extension 15, and a 4:1 ratio of the diameter of the detent springs 7 to the thickness of the layer of material covering the bottom of the retaining groove has proved particularly advantageous. It results in a twofold to fourfold increase in the spring force. 16 denotes the release notches which are mounted in the region of the ends of the bolt 5 in the anti-clanking webs 9, 10 and which provide free space for the hammer used to knock the bolt 5 into the locking position.

Claims

1. A chain shackle for link chains, with shackle parts connected releasably to one another and with anti-clanking means counteracting the clanking of oval chain links suspended in the shackle, in which the anti-clanking means are designed as elastic buffers made of rubber or plastic which face the rounded portion of the respective chain links suspended.

2. A chain shackle according to claim 1, with two essentially U-shaped shackle halves, each having an inner leg and an outer leg, with a bolt supporting the mutually facing sides of the inner legs in the closing position of the shackle, with at least one detent spring arranged in at least one retaining groove in the bolt, and with two projections forming the anti-clanking means, in which the elastic buffers form anti-clanking webs provided with extensions engaging into recesses in the bolt which serve for anchoring them.

3. A chain shackle according to claim 2, in which the recesses are formed by anchoring grooves arranged at a distance from one another.

4. A chain shackle according to claim 3, in which the anchoring grooves are made annular and are arranged in the region of the bolt ends.

5. A chain shackle according to claim 3 or claim 4, in which the anchoring grooves are undercut.

6. A chain shackle according to any one of claims 2 to 5, in which the anti-clanking webs are bonded to the bolt.

7. A chain shackle according to any one of claims 1 to 6, in which the anti-clanking webs are connected to one another by means of extensions forming bridges.

8. A chain shackle according to any one of claims 2 to 7, in which the bottom of the retaining groove for the detent spring is filled with extensions of the anti-clanking webs, these extensions serving to influence the spring characteristics of the detent spring and to anchor the anti-clanking webs.

9. A chain shackle according to any one of claims 2 to 8, with two detent springs, in which the detent springs are designed as open rings with ring apertures offset 180 degrees relative to one another and located in the region of the anti-clanking webs.

10. A chain shackle according to any one of claims 2 to 9, in which the anti-clanking webs are provided with release notches near the ends of the bolt.

11. Chain shackle according to any one of claims 1 to 10, in which the anti-clanking webs have a Shore hardness A of 40 to 90.

12. A chain shackle according to any one of claims 1 to 11, in which the anti-clanking webs consist of a castable polyurethane elastomer.

13. A chain shackle substantially as described herein with reference to the accompanying drawings.