GB2323617A

GB2323617A - Telescopic Post

Info

Publication number: GB2323617A
Application number: GB9704432A
Authority: GB
Inventors: William Prescott
Original assignee: GRAPHIC PRECISION ENGINEERING
Current assignee: GRAPHIC PRECISION ENGINEERING
Priority date: 1997-03-04
Filing date: 1997-03-04
Publication date: 1998-09-30
Also published as: GB9704432D0

Abstract

The invention provides a telescopic post 1 comprises a plurality of telescopically connected sections 2, 4, 5, each section being essentially circular in cross-section, wherein at least one of the sections is provided with a slot 30 having a recess 31 and at least one of the sections is provided with at least one protrusion 32 to engage with the slot 30 of the or each adjoining section. The post further comprises an inner extension means comprising at least two telescopically connected members 7, 8, 9, 10 mounted inside the plurality of telescopically connected sections 2, 4, 5 and are not rotatable. The or each protrusion 32 is brought into engagement with a recess 31 by rotating one of the said sections relative to another, locking means 11 being provided to lock one of the said sections to the inner extension means when the or each protrusion is engaged with a recess. In a second embodiment, Figs 6-9, a securing member 51 is mounted on the lower end of the upper outer telescopic member and is rotated to engage slots in the other outer telescopic members to hold them in a raised position.

Description

TELESCOPIC POST Field of the Invention This invention relates to telescopic posts.

Background to the Invention Over recent years there has been a growing requirement for devices which are capable of preventing access through entrances to a site when it is undesirable for access to be possible, but which will permit access when required by one with a legitimate right to gain access.

Such devices in their most widely known form comprise lockable gates. However, gates have disadvantages. They require posts which are costly to install, and also limit the width of a vehicle which may pass through the entrance. Also, gates can often be lifted off their hinges, or even driven through with a vehicle. This latter act is often known as "ram raiding". Other devices proposed have comprised a post hingedly mounted to a plate fixed to the ground. When access is required the post can be pivoted about the hinge so that it lies substantially parallel to the ground, but when access is to be denied the post is brought to its upright position and locked.

The above mentioned posts have been put to other uses. For instance, they have been installed in front of premises such as shops, car dealers showrooms etc. in an attempt to prevent "ram raiders" gaining entry to such premises simply by driving a vehicle through a window or shop front.

Another use which has been found for such posts has been to prevent the theft of vehicles, and in particular trailers and caravans. Such vehicles can be made secure by locating a post at distance away from a wall or fence which is slightly greater than the length of the vehicle. The vehicle is then parked between the wall and the posts, and the posts brought into their upright position and locked. The vehicle cannot then be removed without removing the posts.

Such posts are however relatively weak at the point of the hinge and the lock. This means that they are relatively unsuccessful at preventing "ram raids". Also, the hinge and lock may be destroyed by hitting the post with a large object, such as a sledge hammer.

It would there fore be desirable to provide a device which would be simple to use, easy and inexpensive to install, and provide better performance against destructive force than known devices.

Summary of the Invention The invention provides a telescopic post comprising at least two sections, one telescopically mounted within the other, a securing member mounted in a first of the two sections, the securing member being adapted to co-operate with at least one indentation, aperture or protrusion in a second of the two sections when the post is in an extended position, actuation means to move the securing member between a first position in which the securing member co-operates with the or each indentation, aperture or protrusion to hold the post in an extended position and a second position in which relative movement of the first and second sections one to another is permitted, and a locking member arranged to lock the actuation means when the securing member is in its first position.

Preferably, the post further comprises a third section telescopically mounted between the first and second sections and provided with an aperture through which a part of the securing member may pass.

Preferably, the securing member is mounted towards one end of the first section and the actuation means is mounted towards the other end thereof, means to connect the securing member to the actuation means being provided. More preferably, the means to connect the securing member to the actuation means comprises a rod or bar extending between and being attached to the securing member and the actuation means.

In one embodiment of the invention, the securing member comprises a rotatably mounted body having at least one and preferably two arms extending therefrom, the length of the or each arm being adapted to co-operate with the or each indentation, aperture or protrusion in or on the second section, and where provided, the aperture in the third section.

The rotatably mounted body is advantageously spring loaded such that the or each arm is biased into engagement with the corresponding indentation, aperture or protrusion.

The or each indentation, aperture or protrusion may be shaped so as to from a slot.

Advantageously, the second section may be provided with means to attach the telescopic post to the ground. Such means may comprise a plate having apertures therein to enable the plate to be bolted to the ground, or simply protrusions. Such protrusions are advantageous where the post is to be sunk into the ground, perhaps into concrete, because removing the post is then exceedingly difficult.

The actuation means may comprise a bar rotatably mounted in a tube. Advantageously, a lock is provided in the bar which locks the bar with respect to the tube, thereby locking the securing member in a desired position. Preferably, the lock is arranged so that when the securing member is in its first position, the bar is locked in position with respect to the tube. Advantageously, the lock is a barrel lock and can be unlocked and/or locked by a suitable key.

The actuation means is suitably mounted in a plate which extends across the first section.

The first and second sections are so shaped as not to permit relative rotation of the first and second sections. The first and second sections may be polygonal in cross section, and may have any number of sides, e.g.

3, 4, 5, 6, etc. Preferably, the first and second sections are square or rectangular in cross section.

In one embodiment of the invention each section is provided with a slot extending in the axial direction of each section, and through or into which a peg may pass to limit the degree to which the post may be extended.

The invention also provides a telescopic post comprising a plurality of telescopically connected sections, each section being essentially circular in cross-section, wherein at least one of the sections is provided with a slot having a recess and at least one of the sections is provided with at least one protrusion to engage with the slot of the or each adjoining section, the post further comprising an inner extension means comprising at least two telescopically connected members mounted inside the plurality of telescopically connected sections, wherein the or each protrusion is brought into engagement with a recess by rotating one of the said sections relative to another, locking means being provided to lock one of the said sections to of the inner extension means when the or each protrusion is engaged with a recess.

Preferably it is the upper most section which is provided with the locking means.

An end most member of the inner extension means may be fixed to one of the sections. Advantageously, an end most member is adapted to co-operate with the locking means to secure the post in its extended position.

The locking means may be provided on one of the sections of the post, and preferably on the inner most section (which when the post is extended is the uppermost section).

Preferably, the slot is essentially "L" shaped.

The inner extension means may be connected to one of the at least two sections of the post by means of at least one spring, and preferably two springs. The or each spring may be a coil spring.

Advantageously, the telescopic post comprises three sections.

Seals may be provided between the sections of the post to prevent ingress of water. Alternatively, or in addition, drain wholes may be provided in the lower region of the lower most section of the post.

In use, the post is set into the ground, possibly in concrete, preferably so that it protrudes slightly above ground level. When it is desired to extend the post, the upper most section is pulled upwards until the protrusions and pins will permit no further extension, at which point the post is locked in position, either by turning one section relative to another, or by rotating the securing means.

Posts of the invention can be made to any desired height.

The posts of the invention are particularly advantageous because they provide a very strong barrier when extended, and are simple to extend and retract. The fact that the lower most section may be set into the ground, even in concrete, means that the post may not simply be removed. The posts are comparatively cheap to build, and require little in the way of maintenance.

Brief Description of the Drawings In the drawings which illustrate exemplary embodiments of the invention: Figure 1 is a partial cut away view of a post according to one embodiment of the invention; Figure 2 illustrates the locking mechanism used in the post shown in Figure 1; Figure 3 is a sectional view of the post shown in Figure 1 when retracted; Figure 4 illustrates the three sections of the post when disassembled; Figure 5 illustrates the three members comprising the inner extension means in the post shown in Figure 1.

Figure 6 is a sectional view of a post according to a second embodiment of the invention; Figure 7 is a plan view of the securing member used in the post shown in Figure 6; Figure 8 is a sectional view of the locking mechanism used in the post shown in Figure 6; and Figure 9 is a sectional view of the post shown in Figure 6 in its retracted state.

Detailed Description of the Preferred Embodiments Referring now to Figures 1 to 3, there is shown a telescopic post 1 according to the invention comprising three sections 2, 4, 5 telescopically arranged one inside the other. Each section 2, 4, 5 is formed from a tube of substantially circular cross section. It can be seen that the lower section 5 is set into the ground so that it protrudes only slightly above the surface of the ground. This is so that when the upper sections 2 and 4 are retracted into the lower section 5, the movement of vehicles and the like over the top of the post 1 is not hindered. The lower section 5 is provided with a lid 6 which is hingedly attached to one side of the said lower section 5.

In Figure 4, the sections 2, 4, and 5 are shown disassembled. Section 5 is provided with a slot 30 which is essentially "L" shaped. At one end of the slot there is provided a recess 31. Section 4 is arranged telescopically within section 5 so that pin 32 engages with slot 30. Section 2 is arranged to slide telescopically within section 4. Section 2 is provided with a slot 34 which is essentially "L" shaped, and at one end of the slot 34 there is a recess 35. Pin 33 engages with slot 34.

Referring again to Figures 1 to 3, when it is desired to move the post from its retracted state shown in Figure 3 to its extended state shown in Figure 1, the lid 6 is first opened, then the section 2 is lifted upwardly, it sliding inside slot 34 until the base thereof reaches pin 33, at which moment the section 4 begins to be lifted out of section 5 until pin 32 reaches the top of slot 30. When the post is fully extended, it is turned clockwise as far as permitted by "L" shaped slots 30, 34, then the sections 2 and 4 are allowed to drop so that pins 32, 33 engage with recesses 31 and 35 respectively.

A locking mechanism 11 is provided to lock the sections 2, 4, 5 with respect to an inner extension member so that post 1 cannot be retracted.

The inner extension member comprises a plurality of sections 7, 8, 9, and 10 telescopically mounted one within the other. The lower most member 10 is fixed to the base of the post so that it cannot rotate. Member 10 is provided with a slot 36 in which a pin 37 extending from member 9 engages. Member 9 is so dimension that it can slide freely inside member 10, its movement being constrained by the pin and slot 36, 37 which ensure that member 9 can only move vertically and only by an amount which corresponds to the length of slot 36. Member 8 is arranged telescopically within member 9, the slot 39 engaging with pin 38 so as to limit the amount and distance by which the member 8 can move. Pin 40 engages with the slot of member 7 (not shown in detail).

The purpose of inner extension member is to provide a telescopically extendible member which can extend and retract to the same degree as sections 2, 4, and 5, but which is not capable of rotation. This is achieved by fixing the lower most member 10 to section 5, and providing members 7, 8, 9, and 10 with slots and pins.

Uppermost member 7 is also provided with a horizontal slot which can to receive a lever 17 of barrel lock 16. Locking means 11 comprises a cap 12, which is rotatably mounted on section 2, having a collar 13 extending downwardly therefrom into member 7. Collar 13 is provided with a slot through which lever 17 may pass. A barrel lock 16 is mounted in cap 12, and extends downwardly into collar 13.

Attached to hooks 14 on either side of the member 7 and cap 12 are springs 15. Springs 15 are arranged to pull sections 2, 4, and 5 into the locked position, so that when the post is lifted from its retracted position, as pins 32, 33 reach the top and bottom of slots 30 and 34 respectively and twisted clockwise, pins 32, 33 are drawn into recesses 31 and 35 respectively.

When the post 1 is in its extended position, lever 17 of barrel lock 16 engages with the slots in collar 13 and member 7. Lever 17 may engage with the slots either by means of turning lock 16 with a key, or the lever 17 may be spring loaded so that it is biased into engagement with the slots. In either case, a key is required to unlock lock 16. When in the locked position, the post cannot be retracted, because it is not possible to move the post upwardly and hence pins 32, 33 cannot be disengaged from recesses 31, 35.

To retract post 1, barrel lock 16 is unlocked, the post is lifted upwardly, turned anti-clockwise and lowered. Lid 6 is then closed.

Figures 6 to 9 show another embodiment of the invention. The post 20 comprises three telescopically connected sections 21, 22, and 23. Each of the sections 21, 22, and 23 is essentially square in cross- section. The amount by which the post 20 may be extended is limited by the provision of pins on sections 21 and 23 which extend inwardly, and engage with vertical slots provided in section 22.

A securing member 51 is provided in the lower end of section 21.

The securing member 51 comprises a disc 52 having arms 53 extending therefrom. Horizontal slots 54 are provided in section 21, and similar slots are provided in sections 22 and 23. Slots 54 and the horizontal slots in sections 22 and 23 are so arranged that when the post 20 is in its extended state, the slots align. By rotating the securing member 51 when the post 20 is in its extended state, arms 53 pass through the aligned slots, and thereby hold the post in its extended state.

Securing member 51 is connected to one end of a rod 50, the other end being connected to an actuation means 24. Actuation means 24 is mounted in a plate 25 having an aperture therein. Bar 26 sits in the aperture and is connected to rod 50. In the bar 26 there is provided a barrel lock 27 having a lever 28, the lever passing through a slot in the bar when the barrel lock is in its locked state. A tube extends downwardly from plate 25 and is provided with a slot.

In use, the lower section 23 of the post 20 is set into the ground so that it protrudes slightly above ground level (see Figure 9). When it is desired to raise the post, the upper section 21 is lifted upwards until the point of maximum extension is reached. The actuation means 24 is then turned thereby rotating the securing member so that the arms 53 thereof pass through the aligned slots in sections 21, 22, and 23. Barrel lock 27 is then turned so that lever 28 passes through the slots in bar 26 and tube 29, thereby preventing actuation means from being turned and hence locking the securing member 51 so that the post cannot be retracted.

The securing member 51 may be spring loaded so that it is biased into its securing position, i.e. the actuation means has to be turned against the force of the spring to disengage the securing means 51 from slots 54.

Claims

1. A telescopic post comprising a plurality of telescopically connected sections, each section being essentially circular in cross-section, wherein at least one of the sections is provided with a slot having a recess and at least one of the sections is provided with at least one protrusion to engage with the slot of the or each adjoining section, the post further comprising an inner extension means comprising at least two telescopically connected members mounted inside the plurality of telescopically connected sections, wherein the or each protrusion is brought into engagement with a recess by rotating one of the said sections relative to another, locking means being provided to lock one of the said sections to the inner extension means when the or each protrusion is engaged with a recess.

2. A post according to Claim 1, wherein the upper most section is provided with the locking means.

3. A post according to Claim 1 or 2, wherein an end most member of the inner extension means is fixed to one of the sections.

4. A post according to any preceding claim, wherein an end most member is adapted to co-operate with the locking means to secure the post in its extended position.

5. A post according to any preceding claim, wherein the locking means is provided on one of the sections of the post.

6. A post according to any preceding claim, wherein the slot is essentially "L" shaped.

7. A post according to any preceding, wherein the inner extension means is connected to one of the at least two sections of the post by means of at least one spring.

8. A post according to Claim 7, wherein the or each spring is a coil spring.

9. A post according to any preceding claim, wherein the post comprises three sections.

10. A telescopic post comprising at least two sections, one telescopically mounted within the other, a securing member mounted in a first of the two sections, the securing member being adapted to co-operate with at least one indentation, aperture or protrusion in a second of the two sections when the post is in an extended position, actuation means to move the securing member between a first position in which the securing member co-operates with the or each indentation, aperture or protrusion to hold the post in an extended position and a second position in which relative movement of the first and second sections one to another is permitted, and a locking member arranged to lock the actuation means when the securing member is in its first position.

11. A post according to Claim 10, wherein the post further comprises a third section telescopically mounted between the first and second sections and provided with an aperture through which a part of the securing member may pass.

12. A post according to Claim 10 or 11, wherein the securing member is mounted towards one end of the first section and the actuation means is mounted towards the other end thereof, means to connect the securing member to the actuation means being provided.

13. A post according to any of Claims 10 to 12, wherein the means to connect the securing member to the actuation means comprises a rod or bar extending between and being attached to the securing member and the actuation means.

14. A post according to any of Claims 10 to 13, wherein the securing member comprises a rotatably mounted body having at least one two arm extending therefrom, the length of the or each arm being adapted to co-operate with the or each indentation, aperture or protrusion in or on the second section, and where provided, the aperture in the third section.

15. A post according to Claim 14, wherein the rotatably mounted body is spring loaded so that the or each arm is biased into engagement with the corresponding indentation, aperture or protrusion.

16. A post according to any of Claims 10 to 15, wherein the or each indentation, aperture or protrusion may be shaped so as to from a slot.

17. A post according to any of Claims 10 to 16, wherein the second section is provided with means to attach the telescopic post to the ground.

18. A post according to Claim 17, wherein the said means to attach the telescopic post to the ground comprises a plate having apertures therein to enable the plate to be bolted to the ground, or apertured protrusions extending from the post.

19. A post according to any of Claims 10 to 18, wherein the actuation means comprises a bar rotatably mounted in a tube.

20. A post according to Claim 19, wherein a lock is provided in the bar which locks the bar with respect to the tube, thereby locking the securing member in a desired position.

21. A post according to Claim 20, wherein the lock is arranged so that when the securing member is in its first position, the bar is locked in position with respect to the tube.

22. A post according to any of Claims 10 to 21, wherein the actuation means is mounted in a plate which extends across the first section.

23. A post according to any of Claims 10 to 22, wherein the first and second sections are so shaped as to prevent relative rotation therebetween.

24. A post according to Claim 23, wherein the first and second sections are polygonal in cross section.

25. A post according to any of Claims 10 to 24, wherein each section is provided with a slot extending in the axial direction of each section, and through or into which a peg passes to limit the degree to which the post may be extended.

26. A post according to any preceding claim, wherein seals are provided between the sections of the post to prevent ingress of water.

27. A post according to any preceding claim, wherein drain holes are provided in the lower region of the lower most section of the post.

28. A telescopic post substantially as shown in, or as described with reference to, the drawings.