FR2792984A1 - Device for replacement of worn chain link operating in abrasive environment comprises two half-links with clevis and eye ends and transverse cotter and spring washer - Google Patents

Abstract

The device enabling the instantaneous replacement of a link with only a hammer is composed of two half-links terminated at their ends by a clevis and by an eye which fit one into the other. A system of transverse cottering composed of a spindle and a spring washer. By using a hammer a groove is positioned under the washer ensuring the translational connection of the spindle.

Description

- I - The present invention relates to a device for replacing

  chain link working in an abrasive medium for various applications and in particular for

  dragline bucket lifting and pulling chains.

  The existing replacement links consist of two symmetrical or non-symmetrical elements, held by rivets or bolts requiring special tools and a relatively long handling time. The bolt fasteners are in direct contact with the abrasive medium and with the other links, thus causing wear.

  faster and sometimes even a break.

  The device according to the invention overcomes these drawbacks. Indeed made up of two half-links overlapping one another and locked by two transverse axes, themselves held in translation by elastic washers embedded in the material, it allows rapid assembly and disassembly (one shot hammer) and protection of the keying system (no locking element is in contact with the

abrasive medium).

  According to particular embodiments - the two half-links can be identical, consisting of (one half-torus, terminated at one end by a yoke and at the other by an eyelet containing the housing of the

elastic washer (counterbore).

  -the axes may include a chamfer making it possible to separate the elastic washer during assembly and a chamfered groove which by the release of the spring will maintain the axis in

  position. Their length will not be greater than the height of the screed.

  - the spring washers can be chamfered and split allowing the

distortion to occur.

  The accompanying drawings illustrate the invention:

  Figure I shows the device mounted on a chain.

  Figure 2 shows the half link.

  Figure 3 shows in section the assembly sequence of the device of the invention.

  FIG. 4 represents a variant of the device With reference to FIG. 2, the half-link presented consists of a clevis Rep

  1 of a Rep 2 half-torus and a Rep 3 eyepiece comprising a Rep 4 counterbore.

  Referring to Figure 3, the device of the invention consists of two half

  identical links to figure 2. The eyepiece Rep 3 of the right part is introduced into the clevis Rep 1 of the left part after having housed the spring washer Rep 9 in the woolen fabric Rep 4. The washer is then trapped between eyecup and yoke. A hammer blow on the axis allows to separate the washer and to position the groove Rep 7 under the spring Rep 9 thus ensuring the connection of the axis. The Rep 8 chamfer facilitates the penetration of

the axis in the washer.

  When the assembly is assembled, no keying element is in contact with the

  abrasive medium with the chain links.

  Disassembly will be carried out by striking with a hammer on a flush

  pin, a metal rod or a bolt placed on the axis Rep 6.

  A variant in FIG. 4 shows the possibility of having only one axis to dismantle,

the other being fixed by welding.

  The device must be sized to take up the admissible loads in the

chain.

-3 -

Claims (1)

  l) Device for replacing a chain link working in an abrasive medium and in particular for lifting and pulling chains of dragline buckets, characterized in that it comprises two half-links having at one end a yoke (1), an eyelet (3) fitting into each other and locked by a transverse keying system protected from the abrasive medium 2) Device according to claim I characterized in that the keying system   consists of a chamfered axis provided with a groove (7) and an elastic washer (9).   3) Device according to claims I and 2 characterized in that the eyecup   has a countersink (4) for housing the washer (9) and a hole (5) for the passage of the axis (6). A hammer blow on the axis allows to position the groove (7) under the elastic washer (9) which is maintained, when the two half-links are assembled, by the bottom   counterbore (4) on the one hand and the screed (1) on the other.