GB2113179A - Improvements in or relating to container spreaders - Google Patents

Abstract

A container spreader 1 is provided with a pair of laterally- disposed load-support beams 2 arranged in substantially parallel array wherein each (main) beam 2 is provided with a pair of releasably retained interchangeable twist-lock units 3 for controlled engagement with pick-up points of a cargo container. Each beam 2 is also provided with a pair of lifting points 6 whereby the spreader can be lifted by a crane or like transporter. A pair of (subsidiary) beams 7 form spacer structure extending between and connected (by welding) to the load- support beams 2. The beams 7 are disposed in substantially parallel array. Cross beams 16 extend between the beams 7 and are used to support journal bearings 17 locating a shaft 18 rotatable (in this example) by a hydraulic jack 19. The shaft 18 is rotatable through 90 DEG in either direction whereby the twist-lock units 3 are made to switch simultaneously from operative to non-operative positions, and vice versa. The twist- lock units 3 may be easily convertable from a "right-hand" unit to a "left- hand" unit and vice versa. <IMAGE>

Description

SPECIFICATION Improvements in or relating to container spreaders BACKGROUND OF THE INVENTION This invention relates to container spreaders, that is to say, to spreaders used by cranes and the like to lift cargo containers.

SUMMARY OF THE INVENTION According to one aspect of the invention, a container spreader is provided with a plurality of twist-lock units for controlled engagement with pick-up points of a container, the units and associate support structure of the spreader having inter-locating portions whereby the units are releasably retained by the spreader.

The support structure portions of the spreader preferably define jaws, and the twist-lock units are of waisted form whereby the waisted portions of the units are received by the jaws.

The invention also comprises a twist-lock unit perse and further comprises the container spreader per se.

A twist-lock unit is preferably constructed so as to be easily convertible from a "right-hand" unit to a "left-hand" unit, and vice versa.

According to another aspect of the invention, a container spreader comprises a pair of loadsupport beams, each load-support beam being provided with a pair of twist-lock units for controlled engagement with pickup points of a container, as well as a pair of lifting points whereby the spreader can be lifted by a crane or the like, and spacer structure extending between and connected to the load-support beams.

According to yet another aspect of the invention, a container spreader is provided with a pair of spaced-apart load support-beams and means are provided for varying the distance between the beams.

The distance between the load-support beams may be varied by use of telescopic structure.

According to a further aspect of the invention, a container spreader is provided with a pair of spaced-apart load-support beams and means are provided for attaching further load-support beams to the spreader whereby containers of differing lengths can be lifted by the spreader.

BRIEF DESCRIPTION OF THE DRAWINGS The various aspects of the invention will now be described, by way of example only, with reference to the accompanying drawings, wherein: Figure 1 is a side view of a container spreader, with parts removed, Figure 2 is a plan view of the spreader of Figure 1, Figure 3 is an end view of one of the lifting points of the spreader, Figure 4 is a side view of the lifting point, Figure 5 is a fragmentary plan view of a pick-up point of a container, Figure 6 is a fragmentary side view of the pickup point of Figure 5, Figure 7 is a side view of a twist-lock unit disposed in the end of a main beam, but with the twist-lock member removed, Figure 8 is a plan view of the arrangement illustrated by Figure 7, Figure 9 is a fragmentary side view, illustrating the lower end of a twist-lock member, Figure 10 is an inverted plan view of the lock member, Figure 11 is an inverted plan view of the Figure 7 arrangement, but with added parts, Figure 12 is a fragmentary plan view of twist-lock unit locating end of a main beam, buf with the unit removed, Figure 1 3 is a view looking in the direction of arrowA of Figure 12, Figure 14 is a view looking in the direction of arrow B of Figure 13, Figures 1 5 and 1 6 are side views of the body of a twist-lock unit, taken from angles spaced at 900, and Figure 1 7 is a view looking in the direction of arrow C of Figure 1 6.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT With reference to Figures 1 and 2, a container spreader 1 is provided with a pair of laterallydisposed load-support beams 2 arranged in substantially parallel array. Each (main) beam 2 is provided with a pair of twist-lock units 3 for controlled engagement with pick-up points 4 (Figures 5 and 6) of a cargo container 5. Each beam 2 is also provided with a pair of lifting points 6 whereby the spreader can be lifted by a crane or like transporter. A pair of (subsidiary) beams 7 form spacer structure extending between and connected (by welding) to the load-support beams 2.

The twist-lock units 3 are disposed adjacent the ends of the beams 2. The units 3 on the left-hand beam 2 (as illustrated in the figures) are disposed behind end covers 8.

The right-hand beam 2 is normally provided with end covers 8 but these are not illustrated by the figures.

The main beams 2 also carry cargo lamps 1 5.

The subsidiary beams 7 are disposed in substantially parallel array. Cross beams 1 6 (Figure 2) extend between the subsidiary beams 7 and are used to support journal bearings 1 7 locating a shaft 1 8 rotatable (in this example) by a hydraulic jack 1 9. The shaft 18 is rotatable through 900 in either direction.

As shown in Figures 3 and 4, each lifting point 6 comprises a pair of spaced brackets 25 formed with aligned apertures which locate a removable pin 26. Removal of the pin 26 is facilitated by a handle 27 movable within one end of the pin and which can be dropped into a retainer 28 whereby accidental removal of the pin is prevented.

As show in Figure 2, the lifting points 6 are disposed outboard of and adjacent to the subsidiary beams 7. The lifting points 6 occupy little headroom, which is advantageous.

With reference now to Figures 5 and 6, each container pick-up point 4 is of standard form, comprising an elongated hole 35 formed in plate structure 36.

Figures 1 5 and 1 7 illustrated the body 40 of a twist-lock unit. The body 40 is of part-circular cross-section, the non-circular part being flat.

The body 40 is formed with a central bore 41 and comprsies axially-spaced flange portions 42, 43 defining a grooved or waisted portion 44, and a pair of laterally-spaced lug-like projections 45 extending from flange portion 43. The space between the inner surfaces of the projections 45 is part-circular and comprises, in effect, an extension of the central bore 41. The flange portions 42, 43 are formed with pairs of aligned holes 42a, 43a.

Figures 9 and 10 illustrate a twist-lock member 50, comprising a shank portion 51 of circular cross-section, and a locking portion 52 having a shape somewhat like a blunt arrow-head. The locking portion 52 is formed so that its profile, as viewed in Figure 10, has substantially the same shape and dimensions as that bounded by the outer and side surfaces of the spaced-apart projections 45, as viewed in Figure 17.

When a twist-lock unit 3 is assembled, the shank portion 51 of its twist-lock member 50 is located, with small clearance, by the bore 41 of the body 40 (Figure 17), with the locking portion 52 disposed beneath the projections 45. In one position, (the passive or non-operative position), the perimeters of the locking portion 52 and projections 45 are in substantial alignment whereby these components can be inserted, with some side-clearance, into an elongated hole 35 (Figure 5) of a pick-up point 4. In another position, (the active or operative position), achieved by turning the shank portion 51 through 900, the locking portion 52 is twisted round so that its longitudinal axis 56 is disposed at right angles to the longitudinal axis 37 of the elongated hole 35.

Obviously, in this position the locking portion 52 cannot be withdrawn back through the elongated hole 35 and hence the locking unit 3 is fully engaged with the container pick-up point 4.

With reference to Figures 11, 1 2, 13 and 14, the extremities of a main beam 2 which is hollow, are open-ended. The twist-lock units 3 are demountably located within the ends of the hollow beams. The ends can be closed, as illustrated by removal structure comprising keep plates 60, of "L"-like form. (When viewed in plan - see Figure 11). Each plate 60 is demountably secured to the associated end of a beam 2 by bolts 62 (Figure 11) fitted through aligned holes 63. 64 formed in the beam 2 and shorter limb of the plate 60 respectively. As best shown by Figure 12, when the plate 60 is secured in place, the longer limb of the plate bears against a stop 65 welded to the inside of the beam 2.

The lower end parts of the beams 2 define jaw portions 70 of "U"-like form when viewed in plan.

(See Figure 12). The jaw portions 70 receive, with some side-clearance, the waisted portion 44,of a twist-lock unit 3. (See Figure 7). The jaw portions 70 are reinforced by backing plates 71.

With reference to Figures 7 and 8, with a twist lock unit 3 in position, the flange portion 42 thereof is supported by that part of a beam 2 forming a periphery of the associated jaw portion 70. As best shown by Figure 11, the unit 3 is disposed so that the flat side of the body 40 is contiguous with the longer limb of the keeper plate 60 so as to prevent rotation of the body 40.

With further reference to Figures 7 and 8, the body 40 of a twist-lock unit 3 is capped by a cover 75 which in use is secured by a nut, bolt and washer assembly 76, to the upper end of the shank portion 51 of a twist-lock member 50.

(Figure 9). The upper end of the shank portion 51 is formed with flats and the bottom surface of the cover 75 is correspondingly recessed whereby the cover 75 and portion 51 inter-engage. Thus, if the cover 75 is rotated relative to the body 40, the shank portion 51 is correspondingly rotated. The cover 75 rests on a tubular spacer 80 which fits over the body 40 and which in turn. rests on a "TEFLON" ring 81 supported by the flange portion 42 of the body.

The upper surfaces of the cover 75 is formed with a pair of radially-extending slots 77, the axes of which are disposed substantially at right angles to each other. The slots 77 provide alternative locations for a lever 78, the outer end of which carries an upstanding spigot 79. In use, the spigot 79 is connected, by way of a lever and crank (not shown) to one end of the shaft 1 8 shown in Figure 2. It will be appreciated therefore that the shaft 18, jack 19 and associated levers and cranks, provide actuating means whereby rotation of the shaft 1 8 through 900 causes simultaneous twisting of the locking portions 52 of the four units 3 from inoperative to operative postions, and vice versa. As the twist lock members 50 rotate, the spacers 80 turn therewith, on the bearing surfaces provided by the "TEFLON" rings 81.

The alternative location of levers 78, provider by slots 77, allow a unit 3 to be transferred from a "right-hand" end of a beam 2 to a "left-hand" end thereof, and vice versa. Thus a unit 3 can be viewed as a universal twist-lock unit, interchangeable with the other units of the spreader 1. The alternative positions of a pin 90 referred to below, contribute to this versatility.

The aligned holes 42a, 43a in the unit 3 of Figures 7 and 8 slidably locate a pin 90 with a support flange 90a substantially midway of its length. A bracket 91 is disposed adjacent the pin 90 and is secured to the beam 2. The bracket 91 carries a plate 92 formed with a hole through which theupper end of the pin 90 extends. This upper end is pointed and is engageable (as shown in Figure 7) with the roller 93 of a roller-carrying actuator 94. The actuator 94 is part of a limit switch assembly 95 which is carried by the bracket plate 92. A compression spring 96 is disposed between the bracket plate 92 and the pin flange 90a.

In the position shown in Figure 7, the lower end of the pin 90 extends downwardly, beyond the flange portion 43 of the unit body 40. It will be appreciated that when the lower end of the unit 3 is inserted into an elongated hole 35 (Figure 5) with the associated twist-lock member 50 in an inoperative position, contact between the pin 90 and the material of the pick-up point surrounding the hole 35 causes upward movement of the pin.

This movement of the pin 90, against the spring 96, causes the actuator 94 to operate the switch assembly 95.

The switch assembly 95 is used to control the hydraulic jack 19 (Figure 2) whereby shaft 18 cannot be rotated by the jack unless first allowed by correct operation of the assembly.

It will be appreciated that alternative sets of holes 42a, 43a (see Figures 1 5 and 17) also allow conversion of a unit 3 from a "right-hand" to a "left-hand" unit and vice versa.

The cover 75 is profiled (see Figure 8) so as to allow it to rotate without interfering with the pin 90.

The spacer structure, i.e. the subsidiary beams 7, may be of telescopic form whereby the effective length of each beam may be varied.

The invention provides a container spreader having easily accessible, easily replaceable, and wholly interchangeable twist-lock untis. The spreader compares advantageously with presently known spreaders, particularly those where twistlock units can only be replaced by first cutting away surrounding metal, or after many hours of dismantling.

In addition to, or instead of the use of hydraulic means (or the mechanical equivalent thereof) to rotate the shaft 18, manually operated means may be employed. For example, by use of a lever, assisted by gears if necessary.

Other advantages of the various aspects of the invention will be apparent from this disclosure.

Claims (17)

1. A container spreader provided with a plurality of twist-lock units for controlled engagement with pick-up points of a container, the units and associated support structures of the spreader having inter-locating portions whereby the units are releasably retained by the spreader.

2. A spreader as claimed in Claim 1, wherein the support structure portions of the spreader define jaws, and the twist-lock units are of waisted form whereby the waisted portions of the units are received by the jaws.

3. A spreader as claimed in Claim 2, wherein a twist-lock unit comprises a body formed with a central bore, a pair of axially-spaced flange portions and a pair of laterally-spaced lug-like projections defining an extension of the central bore.

4. A spreader as claimed in Claim 3, wherein a twist-lock unit further comprises a twist-lock member movable between operative and nonoperative positions, the member having a shank portion located by the central bore and locking portion shaped so that, in the inoperative position of the twist-lock member the perimeters of the locking portion and the lug-like projections are in substantial alignment.

5. A spreader as claimed in any one of Claims 1 to 4, comprising a pair of load-support beams, each load-support beam being provided with a pair of said twist-lock units, as well as a pair of lifting points whereby the spreader can be lifted by a crane or the like, and spacer structure extending between and connected to the load-support beams.

6. A spreader as claimed in Claim 5, wherein said spacer structure comprises a pair of subsidiary beams.

7. A spreader as claimed in Claim 6, wherein the effective length of each subsidiary beam is variable.

8. A spreader as claimed in any one of Claims 4 to 7, provided with actuating means for simultaneous movement of the locking portions of the twist-lock members from operative to inoperative postions and vice versa.

9. A spreader as claimed in Claim 8, wherein said actuating means comprise fluid actuator means.

1 0. A spreader as claimed in Claim 8, wherein said actuating means comprise manually-operated means.

11. A spreader as claimed in any one of Claims 1 to 10, wherein the twist-lock members are constructed so that they are interchangeable with each other.

12. A spreader as claimed in any one of Claims 5 to 11, wherein the load-support beams are hollow and the twist-lock units are demountably located within the ends of the hollow beams.

13. A spreader as claimed in Claim 10, wherein the ends of the beams are closable by removable structure.

14. A twist-lock unit per se, as set forth in any one of Claims 1 to 13.

1 5. A spreaderperse. as set forth in any one of Claims 1 to 13.

1 6. A container spreader, substantially as hereinbefore described witv reference to the accompanying drawings.

17. A twist-lock unit, substantially as hereinbefore described with reference to the accompanying drawings.