Locking Mechanism for Use With Staging System

Abstract

A staging system includes a locking mechanism that enables adjacent staging modules to be locked together in multiple positions to form a stage. The locking mechanism is able to be operated from above the stage.

Description

This invention relates to a locking mechanism for use with a staging system in which adjacent modules can be joined together by an operative positioned on top of the staging.

All staging systems have provision for joining adjacent staging modules. In most cases this in achieved by clamping the legs together, or by links which are inserted into the platforms from below or from the side. This is inconvenient for the operators for whom speed of assembly is very important. Some staging systems have linking devices which can be operated from the top of the staging, by inserting a key into a hole near the edge of the modules to linked, and turning the key. However the operation of these linking systems is very restrictive because they only work when the mechanism on one module is precisely aligned with a corresponding receptor on the adjacent module. Therefore there is only one position in which adjacent modules can be joined.

Many staging systems incorporate small T slots around their peripheries, but a problem with these is that the T bolts and accessories, which are designed to make use of these slots have to be inserted from the end of the slot, and slid along to the required position. This is awkward and if another the bolt is already in position it may not be possible to slide a new T bolt to the required place.

It is therefore an objective of the present invention to provide a staging system in which adjacent staging modules can be linked together by the activation of a key or lever operable from above the stage, and in which the relative positions of the two modules to be joined is unimportant.

According to the present invention there is provided a platform, which comprises a frame around the periphery, with sheet material spanning one side of the frame to the other. Typically the frame is made of aluminium, and the sheet material is made of wood or fibreglass. In one embodiment of the invention the sheet material has a thin upper sheet of wood and a thin lower sheet lower sheet of wood or aluminium, with longitudinal ribs adhesive bonded to each of them so as to provide a very light weight structure.

The aluminium frame incorporates elements to join it to the sheet material, and a T shaped slot, which runs all around the vertical surface of the edge of the staging module.

In one embodiment of the invention, each module incorporates four mechanisms, one on each side, which operate as retractable T bolts. When the module is not required to be joined to another, the head of the T bolt is retracted so that it sits at the bottom of the T slot in which it is mounted. In this position it causes no obstruction to other modules, which may be placed adjacent, nor to any of the other accessories such as handrails, which make use of the T slots for mounting. However, when it is required to join two adjacent modules, a key is inserted into a hole in the top of the module, and turning the key causes the T bolt at first to extend so that its head is within the T slot of the adjacent module; further turning of the key causes the head of the T bolt to rotate so that its tips engage with the T slots of the adjacent module; and final turning of the key causes the T bolt both to rotate further and to retract slightly, thereby pulling the two modules closer together. In this position a spring loaded catch locks the mechanism in place so that the attempted movement of one module relative to the other does not cause the opposite rotation of the T bolt.

In an alternative embodiment of the invention, linking mechanisms are not provided as a permanent part of each module, but are supplied separately and used only when required. Thus no obstruction is caused when they are not in use, because they can be removed from the module altogether.

In this embodiment, the links are effectively double headed T bolts and a thin lever arm attached to a point mid way between the two heads extends upwards through a narrow crack between the two adjacent modules. This lever arm is so arranged that when the two modules are properly joined the top of the lever lies on the surface of the staging so as not to trip people up. The two heads are twisted relative to one another so that the device can be inserted into one module and rotated slightly so as to say there without risk of it falling out whilst the other module is brought close to it in preparation for activation of the link.

The invention is further described with reference to the accompanying drawings, in which:

FIG. 1 is a perspective of the main parts of a first embodiment of the invention. In this view the housing, which holds the moving parts in the correct relation to one another has been omitted for clarity, and the parts have been exploded.

FIGS. 2 and 2 a are orthogonal views on the side of a staging module, showing the positions of the T bolt in its retracted and extended positions.

FIG. 3 is a series of orthogonal views of the linking devices of the second embodiment. FIGS. 3a, 3a′, and 3a″ show the device as it is applied to the first module to be linked. FIGS. 3b, 3b′ and 3b″ show the device once it is attached to the first module, and is ready to accept the second module. FIGS. 3c, 3c′ and 3c″ show the device once the two modules are locked together. FIGS. 3a, 3b and 3c show a section through the device. FIGS. 3a′, 3b′ and 3c′ show an end elevation of the device. FIGS. 3a″, 3b″ and 3c″ show an orthogonal section through the device. FIGS. 3c and 3c′ are shown without the edge extrusion of the second module.

The version of the device shown in FIG. 1 consists of a T bolt 1, a ball stud 2, a wheel 3, a ball bearing 4, a compression spring 5, and various housing components, which for clarity have not been shown. The housing components hold the illustrated parts in the correct relationship and constrain them to rotate or slide as appropriate.

The T bolt 1 is able to rotate about its own axis and to slide axially. A ball stud 2 protrudes laterally from the shaft 1a of the T bolt and engages in hole 3a near to the periphery of the wheel. The wheel is constrained to rotate about its axis 3b. A socket 3c in the top of the wheel is shaped to receive a key that can be inserted into it from above. Turning the key causes the wheel to rotate, which in turn causes the T bolt to slide axially and to rotate at the same time. Careful positioning of the wheel relative to the T bolt axis causes the motion of the T bolt as the wheel rotates to be initially mainly axial, and subsequently mainly rotational. A spring 5 pushes a ball bearing 4 against the outer edge of the wheel such that when the wheel is at each end of its travel the ball bearing engages with detents 3d and 3e in the edge of the wheel, causing the wheel to tend to remain in either of these positions.

FIG. 2 a shows the edge frame of the staging module 6, the sheet material 7 which spans the frame, a hole 8 in the sheet material which gives access to the socket in the top of the wheel, and the T bolt 1 in its retracted position. In this position the head 1b of the T bolt is completely recessed.

FIG. 2 b shows the same components but with the T bolt in its extended position, and engaging the edge frame 9 of an adjacent staging module. The width of the T bolt head is sized appropriately relative to the height of the T slot in the edge frame, so as to ensure that adjacent modules are held at the same height. The position of indent 3e in the edge of the wheel is such that in the configuration shown in FIG. 2b the T bolt is just beginning to retract thereby drawing adjacent staging modules closer together.

The head of the T bolt 1b may be shaped into a helix, like an aeroplane propeller so as to aid the process of drawing the tow modules together as the T bolt turns.

The shaped socket 3c in the top of the wheel could be replaced by a permanent handle recessed into the top of the staging module, thereby eliminating the need for a tool to operate the locking device.

The embodiment of the invention shown in FIGS. 3a to 3c″ consists of a part (e.g. injection moulded) comprising a lever 101, T head 102, T head 103, and boss 104. The operation of the device is as follows:

First the device is fixed to one of the modules to be joined by pushing it into the slot of the module in the position shown in FIG. 3a and rotating it to the position shown in FIG. 3b. To achieve the position shown in FIG. 3a it is necessary initially to bend the lever 101 so that the finger grip 105 clears the edge of the frame 106. Once in the position of FIG. 3b the lever springs back to its flat position and the finger grip prevents it from accidentally returning to position of FIG. 3a. Thus, the device is now locked to the edge frame of the first module, ready to accept the second module, which is to be joined to the first.

In this position the T head 103 is just engaging the edge frame 106 of the first module, but the T head 104, which is angularly offset from T head 103 is aligned so as not to engage the second module. Boss 104 protrudes from the edge of the module and is tapered so that as the second module is brought into proximity to the first, any discrepancy in height is corrected as the two modules are pushed together.

Once the two modules have been pushed together the device can be rotated to the position shown in FIG. 3c. In this position T heads 102 and 103 are both fully engaged with their respective edge frames, and the two staging modules are locked together.

The outer peripheries of T heads 102 and 103 are shaped so that as the device is rotated any discrepancy in height of the two modules is eliminated by a cam like action. This cam like action is arranged with an over centre effect so that some resistance is encountered in moving the device back from position 3c to position 3b. T head 103 has a helical lead in, like an aeroplane propeller, so that as the device is rotated the two modules are pulled closer together. This ensures that the device can be rotated from position 3b to position 3c even if the two modules are not initially pushed together completely. The shape and position of finger grip 105 is such that is position 3c the finger grip lies flat on the top of the staging module.

Whilst the reversible locking mechanism has been described hereinabove in terms of the locking of one staging module to another, it will be appreciated that other locking uses can also be envisaged, in which one module is required to be fixed to another.

It will also be appreciated that the invention encompasses the locking mechanism itself and in conjunction with one or more staging modules.

There is provided a staging system in which adjacent modules can be locked together in multiple positions by the action of a locking means operable from above the stage.

Suitably, the staging system comprising a locking mechanism that enables adjacent staging modules to be locked together in multiple positions to form a stage, wherein the locking mechanism is operable from above the stage.

Suitably, the locking means is an integral part of each stage module.

Suitably, the locking means comprises separate elements that may be attached to the modules prior to joining them together.

Suitably, the means to activate the locking means is accessed by a small gap between the adjacent modules.

Suitably, the locking means accommodates and rectifies discrepancies in the heights of adjacent modules upon activation.

Suitably, the locking means draws adjacent modules closer together upon activation

Suitably, the locking means is effected by the rotation around a horizontal axis of one or more shaped flanges.

Suitably, the locking means does not protrude from the edge of the module when not in use.

Suitably, the locking means retracts entirely within the outer extremity of the module when not activated

Suitably, the locking means does not require a separate tool to operate it.

Suitably, the locking means does not have to be attached by sliding it along to the required position from the end of the staging module.

Claims

1-11. (canceled)

12. A staging system, comprising: a stage having a plurality of modules adjacent one another; and, means for locking together adjacent modules of said plurality of modules in multiple positions, said means for locking being operable from above said stage.

13. The staging system according to claim 12, wherein said means for locking together said adjacent modules is formed as an integral part of each module of said plurality of modules.

14. The staging system according to claim 12, wherein said means for locking together said adjacent modules includes separate elements attached to each module of said plurality of modules prior to joining said adjacent modules together.

15. The staging system according to claim 12, further comprising means for activating said means for locking together said adjacent modules, said means for activating being accessible via a gap between said adjacent modules.

16. The staging system according to claim 12, wherein said means for locking together said adjacent modules accommodates, and rectifies, discrepancies in heights of said adjacent modules upon activation.

17. The staging system according to claim 12, wherein said means for locking together said adjacent modules closer together upon activation.

18. The staging system according to claim 12, wherein said means for locking together said adjacent modules is effected via rotation around a horizontal axis of at least one shaped flange.

19. The staging system according to claim 12, wherein said means for locking together said adjacent modules does not protrude from an edge of a module of said plurality of modules when not in use.

20. The staging system according to claim 12, wherein said means for locking together is entirely retractable when an outer extremity of a module of said plurality of modules is not activated.