GB2173252A

GB2173252A - Gate opening device

Info

Publication number: GB2173252A
Application number: GB08604744A
Authority: GB
Inventors: Allan John Chisholm
Original assignee: Individual
Current assignee: Individual
Priority date: 1985-02-27
Filing date: 1986-02-26
Publication date: 1986-10-08
Also published as: GB8504988D0; GB8604744D0; GB2173252B

Abstract

An automatic gate opening device (1) comprises a first water holder (2) and a displacement member formed and arranged to be displaceable, by the wheel (15) of a vehicle driven over it, so as to displace water therefrom into a second water holder (6) mounted on a support means (7) so as to be reciprocably displacable between a first position and a second position. The second water holder (6) is drivingly connected to a gate drive member (9, 38) connected in use to a gate (4) and reciprocably movable for opening and closing of the gate. The second water holder (6) is movable from its first position to its second position under the influence of water displaced from the first holder (2), whereby the gate is automatically opened by driving a vehicle wheel over the displacement member. <IMAGE>

Description

SPECIFICATION Opening device The present invention relates to automatic gate opening devices and in particular to devices suitable for use in opening gates in the path of a vehicle.

Many tracks and roads in rural areas are unfenced but nevertheless pass through areas containing animals at large. Since the boundaries of such areas sooner or later cross the road or track it becomes necessary to provide gates at such crossings and to ensure that these gates are normally kept closed. As a result, when a vehicle is driven along such a road, the driver or if available a passenger is obliged to dismount at each and every gate in order to open and close the gate. Where a vehicle has to pass a number of such gates a considerable amount of time and inconvenience may be involved.

It is an object of the present invention to avoid or minimise one or more of the above disadvantages.

The present invention provides an automatic gate opening device comprising a first water holder with a displacement member formed and arranged to be displacable, in use, by the wheel of a vehicle driven over it, so as to displace water from said holder into a second water holder mounted on a support means so as to be reciprocably displacable between a first position and a second position, said second water holder being drivingly connected to a gate drive member formed and arranged for connection, in use, to a gate and reciprocably movable between a closed position corresponding to a closed condition of the gate, and an open position corresponding to an open condition of the gate, respectively said second water holder being formed and arranged so as to be movable from said first position to said second position under the influence of water displaced to said second water holder from said first water holder, whereby in use of said device a gate may be automatically opened by driving a vehicle wheel over said displacement member.

Since the gate opening device of the present invention is operated automatically by simply driving the vehicle over the displacement member thereof it will be appreciated that it is no longer necessary to stop the vehicle or for anyone to dismount from the vehicle when negotiating a gate provided with a device of the present invention. As a result considerable time savings may be made and perhaps even more important a considerable amount of driver frustration may be avoided.

In order to maximise the benefits obtainable with the present invention it will normally be desirable to provide two displacement members-one on each side of the gate, though both of these may be connected to a common second water holder.

Further preferred features and advantages of the present invention will appear from the following detailed description given by way of example of a preferred embodiment illustrated with reference to the accompanying drawings in which: Fig. 1 is a general perspective view of a typical gate opening device installation; Fig. 2 is a partly cut-away perspective view of the main parts of the device of Fig.1; Fig. 3 is a detail vertical section illustrating the mode of operation of the displacement member of the device of Fig. 1; and Fig. 4 is a perspective view of an optional component of the displacement member of Figs 1 to 3.

Fig. 1 shows an automatic gate opening device 1 comprising two first water holders 2 sunken into the road surface 3 either side of a gate 4 and connected by suitable subterranean piping 5 to a second water holder 6 mounted inside a housing 7. The second water holder 6 is, in turn, drivingly connected by a gate drive means including underground pressurised fluid transmission piping 8 and a piston and cylinder unit 9 to the gate 4.

As may be seen in Fig. 2 a movable displacement member in the form of a flexible suspension bridge device 10 is suspended across the surface of the water 11 in the open top 12 of the first water holder 2. One end 13 of the suspension bridge device 10 is mounted in one end 14 of the water holder 2 so as to be axially reciprocably displacable against the return force of a bridge tensioning spring 14. Accordingly when the wheel 15 of a vehicle 16 is driven onto the bridge device 10, this is deflected downwardly (see Fig. 1) thereby displacing water from the first water holder 2 down the piping 5 into the second water holder 6.

As may be seen in Fig. 2 the water displaced is brought up to the top of the housing 7 via a spiral conduit 17 and is discharged from the outlet 18 thereof into the top of an annular vessel constituting the second water holder 6. The latter is mounted in the cylindrical housing 7 so as to be receiprocably axially movable therein up and down a central cylinder 18 in which is mounted an operating piston 19 whose piston rod 20 is fixedly connected to the upper end 21 of the central part 22 of the annular second water holder 6. Also connected to said upper end 21 are a pair of cable means 23 which are led over pulleys 24 suspended from the roof 25 of the housing 7 to counterweights 26 which hang down into the interior 27 of the second water holder 6.

In the upper inoperative position of the second water holder 6 as shown in Fig.2 the counterweights 26 rest on the floor 28 of the second water holder 6 and their weight prevents the holder 6 from dropping down.

When, though, a substantial body of water 29 has been displaced into the holder 6 by the displacement member bridge device 10, the increase weight of the second holder 6 causes it to fall pushing down the operating piston 19 which forces water or other suitable hydraulic fluid 30 out of the cylinder 18 through the fluid transmission piping 8 into the piston cylinder unit 9 driving back the piston 31 thereof and with it the gate 4 connected thereto into its open position.

The floor 28 of the second holder 6 is provided with a small conical valve 32 set at a small opening to allow a slow leakage of water from the second holder 6 at a rate such that the weight of the holder 6 and water displaced thereinto are sufficient to maintain the holder 6 in its lowered position corresponding to a fully open position of the gate for enough time to allow the vehicle to pass safely through. Then once enough water has leaked out of the second holder 6 the weight of the counterweights 26 becomes sufficient to raise the second holder 6 back up to its inoperative position thereby retracting the two pistons and closing the gate automatically.

The water leaking out of the second holder drains into the base 34 of the housing 7 whence it can slowly drain back into the subterranean piping 5 adjacent thereto via small drainage outlets 35 which are made small relative to the spiral conduit diameter so as to avoid any significant diversion of water therethrough whilst the surge of water from the first water holder 2 is led up into the second water holder 6.

It will be appreciated that the abovedescribed device is automatic in operation as regards both opening and closing of the gate.

Moreover the device does not require the use of any external energy supply. Thus the device does not involve any significant running costs nor is it susceptible to power failures.

Also since the main operating fluid is water any losses may be readily made up and indeed in the case of the abovedescribed arrangement will be made up automatically by rainwater falling into the open top of the first holders 2. Nevertheless if it is desired to use a sealed system, for example, in order to minimise evaporation losses in dry climates, then the water in the first holder 2 may be contained within a flexible bag 36 of a suitable waterproof material e.g. rubber, which is laid in the first holder 2 under the bridge device 10.

Whilst the device described above will automatically bring the gate back to its closed position it will normally be desirable to provide the gate with a latching device 37 in order to positively secure it against opening. Accordingly the piston rod 38 of the piston 31 of the piston unit 9 is connected to the gate via a short link 39 to which is also connected a light rod 40 connected to the latching device 37 so that an initial movement of the piston 31 causes unlatching of the gate prior to pushing open of the gate.

Fig. 5 is a partly cut away perspective view of the main parts of a further embodiment of an automatic gate installation of the present invention. In this embodiment the first water holder 41 and a chamber 42 in which the second water holder 43, are formed in a single body 42 conveniently of concrete or possibly a suitable plastics material, which is sunken underground below a rolling road device 44. The rolling road device has a main roller 45 and a second roller 46 between which a driven wheel 47 of a vehicle engages to drive the rollers 45, 46 round on suitable bearings 48. The main roller 45 has an annular recess 49 for taking up a rope or cable means 50 whose other end 51 is connected to a piston ball and counterweight means 52 which is suspended in the substantially cylindrical first water holder 41.As the cable 50 is taken up on the main rqller 45 the piston ball is pulled upwardly thereby displacing water 53 from the first water holder 41 through an aperture 54 in the wall 55 of the first water holder 41 into the cylindrical second water holder 43 thereby increasing the effective weight thereof. At the same time, the lifting of the piston ball and counter-balance weight 52 allows a second rope or cable means 54 connected between the piston ball 52 and the driving connection piston 56 secured 57 to the base 58 of the second water holder 43 to pass up and over pulleys 59 thereby lowering the second water holder 43 under its own weight and the weight of the water displaced thereinto.As the second water holder 43 moves downwardly, the driving connection piston 56 displaces hydraulic fluid 60 down the driving connection cylinder 61 and along a hydraulic line 62 to the gate drive member 9, 38 which conveniently is as shown in Figure 1 and accordingly need not be further described at this point.

Once the gate has fully opened, the piston ball 52 having reached the upper limit of its travel inside the first water holder 41, the rolling road device resistance increases sufficiently for the driven wheel to drive on, off the forward end 63 of the rolling road device 44.

This then allows the rope or cable means 50 to unwind and the piston ball counter-balance weight means to fall back under its own weight lifting the second water holder 43 via the second rope or cable means 54. At the same time water from the second water holder 43 is draining progressively away through drain apertures 65 in the base 58 thereof to return to the first water holder 41 via an interconnecting return passage 65 thereby further reducing the effective weight of the second water holder 43 and allowing it to return pulling up the drive connection piston 56. This in turn returns the gate drive member 9, 38 and the gate 4 to the closed position. If desired any return spring could also be provided between the gate 4 and gate post 66 to enhance the gate closing action.

In order to take up any slack in the second rope or cable 54 and avoid disengagement thereof from the pulleys 59, a suitable weight 67 is hung frcm said rope 54 by a suitable pulley means 68 between the two pulleys 59.

It will be appreciated that various modifications may be made to the above described embodiments without departing from the scope of the present invention. Thus, for example, instead of the rolling road device arrangement there could be used a lever device adjacent the offside of the track or roadway which could be grasped by the vehicle driver as he drove slowly past it thereby throwing the lever to a gate opening device and raising the piston ball which is connected to the lever by a rope or cable as before and/or via some other form of mechanical linkage. Some such alternative displacement member arrangement would be required in practice where a vehicle with permanently fixed four wheel drive was being used.

Claims

1. An automatic gate opening device comprising a first water holder with a displacement member formed and arranged to be displacable, in use, by the wheel of a vehicle driven over it, so as to displace water from said holder into a second water holder mounted on a support means so as to be reciprocably displacable between a first position and a second position, said second water holder being drivingly connected to a gate drive member formed and arranged for connection, in use, to a gate and reciprocably movable between a closed position corresponding to a closed condition of the gate, and an open position corresponding to an open condition of the gate, respectively said second water holder being formed and arranged so as to be movable from said first position to said second position under the influence of water displaced to said second water holder from said first water holder, whereby in use of said device a gate may be automatically opened by driving a vehicle wheel over said displacement member.

2. A device as claimed in claim 1 wherein are provided two displacement members-dis- posable, in use of the device, at opposite sides of the gate, and each connected to a said second water holder drivingly connected in turn to a said gate drive member.

3. A device as claimed in claim 2 wherein said two displacement members are connected to a common second water holder.

4. A device as claimed in any one of claims 1 to 3 wherein each said second water holder means is provided with drain means and return passage means formed and arranged for progressively draining water from the second water holder and returning it to the first water holder via said return passage means.

5. A device as claimed in any one of claims 1 to 4 wherein said second water holder is drivingly connected to the gate operating member via a pressurized fluid line having a first end at which is provided a first piston and cylinder means wherein the piston is connected to the second water holder, and a second end at which is provided a second piston and cylinder means wherein the piston is connected to the gate drive member.

6. A device as claimed in claim 5 wherein is used a pressurized hydraulic fluid.

7. A device as claimed in any one of claims 1 to 6 wherein is provided counter-balance weight means formed and arranged for urging said second water holder back to its first position from its second position.

8. A device as claimed in any one of claims 1 to 7 wherein the first water holder is in the form of a water trough and said displacement member is in the form of a suspension bridge means extending across the open top of said water trough means whereby in use of the device a wheel of a vehicle passing over the suspension bridge means displaces it downwardly thereby in turn to displace water from said first water holder to said second water holder.

9. A device as claimed in claim 7 wherein the water in said first water holder is substantially sealingly enclosed in a flexible container disposed in said trough.

10. A device as claimed in any one of claims 1 to 7 wherein the first water holder is in the form of a substantially cylindrical chamber and said displacement member is in the form of a piston member suspended at a first end of a rope or cable means, the second end of the rope or cable means being secured to a roller of a rolling road device so as to be wound up on said roller when at least one driven wheel of a vehicle is driven onto said rolling road device.

11. An automatic gate installation comprising a gate provided with an automatic gate opening device according to any of the preceding claims, the displacement member being disposed at a distance from said gate sufficient to allow the gate to be driven to its open position without interfering with said vehicle.

12. An installation as claimed in claim 11 wherein are provided displacement members at opposite sides of the gate.

13. An installation as claimed in claim 11 or claim 12 wherein the displacement member has a lateral width equal to or greater than a single track width whereby both driven wheels on a given axle can engage the displacement member simultaneously.

14. A device as claimed in claim 11 or claim 12 wherein are provided two displacement members at one side of the gate in laterally spaced apart relation at an approxi mately single track width whereby both driven wheels on a given axle can engage the displacement member simultaneously.

15. An automatic gate opening device substantially as described hereinbefore with particular reference to Figs. 1 to 3, Figs. 1 to 4 or Fig. 5 of the accompanying drawings.

16. An automatic gate installation substantially as described hereinbefore with particular reference to Figs. 1 to 3, Figs. 1 to 4 or Fig.

5 of the accompanying drawings.