GB1563022A - Tensioning device for chains and other lashings having eyelet-links - Google Patents

Description

(54) TENSIONING DEVICE FOR CHAINS AND OTHER LASHINGS HAVING EYELET-LINKS (71) We, SEASAFE TRANSPORT AB, a Company organised under the laws of Sweden, of Olaus Petrigatan 10, 115 34 Stockholm, Sweden, do herebv declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed. to be particularly described in and by the following state ment: This invention relates to a tensioning device for chains and other lashings having eyelet-links at their ends.

When using chains there is ven' often a need to be able to tension them. The same applies to wire ropes. rods and other lashings having eyelet-links. Especially for lashing of heavv loads. for example general cargo or rolling cargo on transport vehicles or ships' decks, such tensioning devices have come into wide use in view of the high tensioning force required and to the very quick tensioning necessarv to avoid the great expense of the time spent especially by ships in harbour. For this purpose a large number of tensioning devices are know.

which work on the leverage principle. To achieve a reasonably great tensional force there must be a given minimum length of lever. so that the length of such devices has a given relation to the attainable tensional force. This means that comparatively bulky tensioning devices are required. for example for lashing of heavy loads on rail cars or ships' decks.

An object of this invention is to provide a tensioning device which can he used to pull together two ends of a chain or other lashing having at those ends evelet-links for attached ment of the tensioning device. According to the present invention there is provided a tensioning device for chains or other lashings having evelet-links. to which said device is to be attached from the side, comprising an oblong. hollow guidc-piece with a first fastening member tor an eyeletlink projecting sideways at one end thereof and non-rotatable in relation to the longitudinal axis of the guide-piece. a housing or sliding piece longitudinally displaceable along the guide-piece and having a second fastening member projecting sideways and non-rotatable in relation to the longitudinal axis of the housing, and a screw-threaded spindle inserted in the cavitv of the guidepiece in its longitudnal direction and in threaded engagement with the housing, the said spindle having an end extending past the guide-piece thus forming a driving connection arranged for engagement with a driving unit so that the housing or slidingpiece and the guide-piece can be easilv and quickly displaced in relation to one another, the fastening members being arranged to project sideways to an extent enabling the tensioning device to be attached to a chain or other lashing extending past the driving connection in such a wav that a motordriven unit can be coupled to said connection unimpeded by the lashing extending bevond it.

Preferablv the tensioning device is arranged so that a line joining the point of englyement of the lashing with the second fastening member on the housing and the point of engagement of the lashing with the first fastening member on the guide-piece forms an angle with the centre axis of the tension device.

The end of the guide-piece remote from the second fastening member on the housing may be closed, and the driving connection arraned at that end.

The housing can therefore be made narrow and the guide-piece and the housing may be cylindrical. The screw-thread on the spindle may have a relativelv low pitch. so that the torquf to be applied to the spindle by the motor-driven unit will also be rela timely low. An arrangement of this kind permits rapid actuation of the tensioning device during loading and discharging, since it will act as a gear reduction device, placed on the chain or other lashing, for a motor unit.

The small lateral dimensions of the housing and the fact that the tensioning device is driven by a motor which can have the same diameter as the housing permit rapid and convenient drawing together of the ends of two chains or wire ropes or tensioning of a chain or wire rope.

The guide-piece may be provided with a longitudinally extending slot in which a guide member of the sliding piece or housing is non-rotatably movable in the longitudnal direction of the guide-piece. The guide member may extend through the guidepiece, be rigidly connected to the housing, and form the second fastening device of the tensioning device. The screw-threaded spindle may be provided with a collar arranged to bear against a shoulder at the end of the guide-piece.

It will be appreciated that using the invention it is possible to provide a compact and robust tensioning device.

A tensioning device embodying the invention will now be described, bv wav of example, with reference to the accompanying drawings, in which: Figure I shows the tensioning device viewed from the side and partly cut away: Figure 2 shows to a larger scale a transverse cross-section through the tensioning device of Figure 1; Figure 3 shows to a larder scale than Figure 2, a longitudinal section through one end of the tensioning device: and Figure 4 shows, to a smaller scale than any other Figure. a chain with, at its side. the tensioning device of Figures 1 to 3 with associated motor.

Referring to the drawings, Figures 1 and 2, show a tensioning decive made up of an oblong. cylindrical hollow guide-piece 1. At one closed end 2 of the guide-piece there is a first chain hook 3 serving as a fastening device for a link of a chain or an evelet-link at an end of a wire rope or other lashing.

Inside the guide-piece 1 there is journalled a screw-threaded spindle 5 which projects out of the guide-piece 1 at its other end A. On the screw-threaded spiindle 5 there is a non-rotatable guide-cam 6. which projects out of a longitudinal slot 9 in the guide-piece 1, and which forms part of a tubular slidable piece or housing 8 carrying a second chain hook 7 and gripping the guide-piece I in a longitudinally displaceable manner. Inside the cylindrical guide-piece I there is an internally screw-threaded nut 1() which also forms part of the sliding piece or housing 8 and is in threaded engagement with the screw-thread of the spindle 5. The slidable piece or housing 8 has slight clearance with the guide-piece 1. The internally screwthreaded nut 10 lies with slight clearance inside the guide-piece 1.In engagement with a chain the chain hooks 3 and 7 provide the entire tensioning device with sufficient guidance at the moderate torques to which it is subjected by a driving motor.

The screw-threaded spindle 5 is journalled also in the hooked end 2 of the guidepiece. The end 11 of the screw-threaded spindle 5 projecting from the guides-piece 1 is formed into a flat-sided connection which can be inserted into a correspondingly flatended co-operating socket of a motor drive, driven for example, by means of a pneumatic motor. Inside the guide-piece 1 the screw-threaded spindle 5 has at its end 4 a collar 12 which can take up axial forces by bearing against the inside of the end 4. This is seen especially in Figure 3.

In Figure 1 another item is shown which enables a chain tensioned by the tensioning device to be kept in a tensioned state while the tensioning device is being released, turned in the reverse direction and then brought back into engagement with the chain for continued tensioning. For this purpose. in the embodiment here shown, there is a third chain hook 13 situated essentially in the same plane as the two other hooks 3 and 7. In order not to be in the way when the chain is tensioned with the tensioning device, the third hook 13 is lowerable in the direction towards the two other hooks. Instead of hooks one can, of course. arrange for this purpose wire-ropefastening devices of known kind. e.g. wedge lock or toggle fastener.

Figure 4, finally, shows use of the tensioning device. A chain 14 has at one end a hook 15 which can be secured in. for example, an evelet on a lorry to be lashed on a ships deck. The other end of the chain is secured bv means of an "elephant foot" 16 in an opening for the purpose in the ship's deck.

When the ends 15 and 16 of the chain have been secured, one hook of the tensioning device is placed in a link of the chain, after which the chain is tensioned by hand and the other hook is inserted in an adjoining link.

The hooks 3 and 7 of the tensioning device are then brought closer together by turning the screw-threaded spindle 5 in the aforesaid manner until the chain has been subjected to the desired tension bv a motor 17 pneumatically driven through a compressed air hose. For this purpose drive socket 19 of the motor 17 is fitted to the drive connection 2() of the tensioning device.

It will be understood that a tensioning device embodying the invention is advan tazeous since it provides a tensioning device of compact and space-saving form and of especially short length in relation to the attainable length of stretch. The attainable tensional force is also great in relation to the length of the device. The tensioning device is moreover very robust and hard-wearing, it being observable that the most delicate part of the device, the screw-threaded spindle, is well protected inside the cylindrical guide-piece. A lorry can be driven over the tensioning device without damaging it. Finally, the tensioning device takes up little space either in use for tensioning or when stowed away after use, which is an advantage also for transport and stocking of the tensioning device.

The tensioning device shown in and described with reference to the drawings has a connection intended for motor drive and thus requires comparatively little space laterally, and one or both fastening devices is or are formed in such a way that the part of the chain or lashing carried past the end of the tensioning device leaves sufficient space for bringing the motor unit into engagement with the connection.

WHAT WE CLAIM IS: 1. A tensioning device for chains or other lashings having eyelet-links, to which said device is to be attached from the side.

comprising an oblong, hollow guide-piece with a first fastening member for an eyeletlink projecting sideways at one end thereof and non-rotatable in relation to the longitudinal axis of the guide-piece, a housing or sliding piece longitudinally displaceable along the guide-piece and having a second fastening member projecting sideways and non-rotatable in relation to the longitudinal axis of the housing, and a screw-threaded spindle inserted in the cavity of the guidepiece in its longitudinal direction and in threaded engagement with the housing, the said spindle having an end extending past the guide-piece thus forming a drive connection arranged for engagement with a driving unit so that the housing or sliding-piece and the guide-piece can be easilv and quickly displaced in relation to one another. the fastening members being arranged to project sideways to an extent enabling the tensioning device to be attached to a chain or other lashing extending past the driving connection in such a wav that a motordriven unit can be coupled to said connection unimpeded by the lashing extending behond it.

2. A tensioning device as claimed in Claim 1, wherein a line joining the point of engagement of the lashing with the second fastening member on the housing and the point of engagement of the lashing with the first fastening member on the guide-piece forms an angle with the centre axis of the tensioning device.

3. A tensioning device as claimed in Claim 1 or Claim 2. wherein the end of the guide-piece remote from the second fastening member on the housing is closed, and the driving connection is arranged at that end.

4. A tensioning device as claimed in any preceding claim, wherein the guide-piece and housing are cylindrical.

5. A tensioning device as claimed in any preceding claim, wherein the screw-thread on the spindle has a relatively low pitch, so that the torque to be applied to the spindle by the motor-driven unit will also be relatively low.

6. A tensioning device as claimed in any of the preceding claims wherein the guidepiece is provided with a longitudinally extending slit in which a guide member of the sliding piece or housing is non-rotatably movable in the longitudinal direction of the guide-piece.

7. A tensioning device as claimed in claim 6, wherein the guide member extends through the guide-piece. is rigidly connected to the housing, and forms the second fastening device of the tensioning device.

8. A tensioning device as claimed in any preceding claim, wherein the screwthreaded spindle is provided with a collar arranged to bear against a shoulder at the end of the guide-piece.

9. A tensioning device for chains or other lashings having eyelet-links, substantially as hereinbefore described with reference to the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (9)

**WARNING** start of CLMS field may overlap end of DESC **. tensional force is also great in relation to the length of the device. The tensioning device is moreover very robust and hard-wearing, it being observable that the most delicate part of the device, the screw-threaded spindle, is well protected inside the cylindrical guide-piece. A lorry can be driven over the tensioning device without damaging it. Finally, the tensioning device takes up little space either in use for tensioning or when stowed away after use, which is an advantage also for transport and stocking of the tensioning device. The tensioning device shown in and described with reference to the drawings has a connection intended for motor drive and thus requires comparatively little space laterally, and one or both fastening devices is or are formed in such a way that the part of the chain or lashing carried past the end of the tensioning device leaves sufficient space for bringing the motor unit into engagement with the connection. WHAT WE CLAIM IS:

1. A tensioning device for chains or other lashings having eyelet-links, to which said device is to be attached from the side.

comprising an oblong, hollow guide-piece with a first fastening member for an eyeletlink projecting sideways at one end thereof and non-rotatable in relation to the longitudinal axis of the guide-piece, a housing or sliding piece longitudinally displaceable along the guide-piece and having a second fastening member projecting sideways and non-rotatable in relation to the longitudinal axis of the housing, and a screw-threaded spindle inserted in the cavity of the guidepiece in its longitudinal direction and in threaded engagement with the housing, the said spindle having an end extending past the guide-piece thus forming a drive connection arranged for engagement with a driving unit so that the housing or sliding-piece and the guide-piece can be easilv and quickly displaced in relation to one another. the fastening members being arranged to project sideways to an extent enabling the tensioning device to be attached to a chain or other lashing extending past the driving connection in such a wav that a motordriven unit can be coupled to said connection unimpeded by the lashing extending behond it.

2. A tensioning device as claimed in Claim 1, wherein a line joining the point of engagement of the lashing with the second fastening member on the housing and the point of engagement of the lashing with the first fastening member on the guide-piece forms an angle with the centre axis of the tensioning device.

3. A tensioning device as claimed in Claim 1 or Claim 2. wherein the end of the guide-piece remote from the second fastening member on the housing is closed, and the driving connection is arranged at that end.

4. A tensioning device as claimed in any preceding claim, wherein the guide-piece and housing are cylindrical.

5. A tensioning device as claimed in any preceding claim, wherein the screw-thread on the spindle has a relatively low pitch, so that the torque to be applied to the spindle by the motor-driven unit will also be relatively low.

6. A tensioning device as claimed in any of the preceding claims wherein the guidepiece is provided with a longitudinally extending slit in which a guide member of the sliding piece or housing is non-rotatably movable in the longitudinal direction of the guide-piece.

7. A tensioning device as claimed in claim 6, wherein the guide member extends through the guide-piece. is rigidly connected to the housing, and forms the second fastening device of the tensioning device.

8. A tensioning device as claimed in any preceding claim, wherein the screwthreaded spindle is provided with a collar arranged to bear against a shoulder at the end of the guide-piece.

9. A tensioning device for chains or other lashings having eyelet-links, substantially as hereinbefore described with reference to the accompanying drawings.