GB2099891A - Traffic barriers - Google Patents

Abstract

A coin-freed traffic barrier, e.g. for car parks, comprises a fixed step- like obstruction (1) able to resist or prohibit the advance of a vehicle, a hinged ramp platform (8) disposed in advance of the step-like obstruction and rockable between a lowered position and a raised position, in which its trailing edge (11) is adjacent the top of the step-like obstruction, spring means (12) urging the platform into its raised position, latch means (15) operable to lock the platform in its raised position to permit a vehicle to advance over the step-like obstruction, and control means including a coin-operated device or the like, for controlling the operation of the latch means. The latch means (15) is normally retained in its latched condition, and the control means is responsive to the front wheels of a vehicle approaching the platform (8) to release the latch means if the driver of that vehicle does not insert the prescribed parking fee in the coin- operated device. The barrier step (1) has an exit ramp unit (3). The barrier is provided with signal lights (37, 40), a swing- out indicator arm (44), and an acoustic warning device. <IMAGE>

Description

SPECIFICATION Traffic barriers The present invention relates to traffic barriers and, more particularly, although not exclusively, to traffic barriers for controlling the exits or entrances to car or vehicle parks.

Existing barrier constructions for controlling the flow of vehicle traffic generally comprise either a hinged arm, which is adapted to be lowered across the path of an approaching vehicle or, alternatively, a hinged or raisable step or plate, which is disposed at ground level and can be moved into a position to obstruct the wheels of an approaching vehicle.

It is customary to open such a barrier by lodging the appropriate fee in a coin-operated control mechanism or by actuating the control mechanism with a token, ticket or card. This effects opening of the barrier to permit passage of the vehicle which automatically actuates the control mechanism to close the barrier after it has negotiated the barrier.

In either type of existing barrier, the barrier, itself, is moved into its operative position by some form of motive device, such as, an electric motor or a hydraulic or pneumatic cylinder. The motive device is operated each time the barrier is opened and closed. When the barrier is used for a car park, the barrier and ancillary equipment are operated every time a vehicle is permitted to pass the barrier and this may require frequent actuation of the barrier and its ancillary equipment. Hence, existing barrier constructions require appreciable quantities of mechanical and electrical control equipment, may be subject to considerable wear, and tend to consume undesirable amounts of energy.A further disadvantage of existing constructions is that they do not reliably restrict the flow to one vehicle upon each operation of the barrier and can permit the unauthorised passage of an additional vehicle when opened.

It is an object of the present invention to provide a traffic barrier which utilizes simpler operating mechanism than hitherto known barriers, is less expensive to operate, and reliably restricts the flow of vehicles to one vehicle for each operation of the barrier device.

The invention consists in a traffic barrier comprising a step-like obstruction adapted to resist or prohibit the passage of a vehicle, a hinged platform disposed in advance of the steplike obstruction and rockable between a lowered position and a raised position, in which its trailing edge is adjacent the top of the step-like obstruction, and means urging the platform into its raised position, characterised by the platform being depressible into its lowered position by a vehicle advancing over said platform from its leading to its trailing edge, whereby the obstruction is presented to the vehicle to resist its advance, latch means operable normally to lock the platform in its raised position, and control means for selectively actuating the latch means, whereby the platform is normally locked in its raised position to permit a vehicle to advance over the obstruction from the platform, said control means being responsive to advance of a vehicle towards the obstruction to release the latch means.

With the present invention, the step-like obstruction is capable of prohibiting passage of vehicles through the barrier in either direction.

Moreover, the platform is normally urged, for example, by spring means, into its raised position and is normally locked in said position by the latch means, and there is no obvious, visible obstruction to the advance of a vehicle. When the prescribed action is taken to signal the control means that the passage of a vehicle is authorised, for example, by lodging the appropriate parking fee in a coin-operated control mechanism for the barrier, the platform remains locked in its raised position to permit the vehicle to advance over the step-like obstruction. On the other hand, if the prescribed action is not taken, the control means actuates the latch means to release the latter, the control means being triggered, for example by the front wheels of the vehicle as they reach or move on to the hinged platform.The weight of the vehicle depresses the trailing edge of the platform; which moves to its lowered position, so that the step-like obstruction is presented to the vehicle and prohibits its advance.

It will be appreciated that, for every vehicle permitted to proceed past the barrier, the platform is locked in its raised position and there is consequently no movement of the barrier or of the latch means. In practice, the platform and latch means only move on rare occasions, so that the barrier mechanism is subject to little wear.

Furthermore, the barrier only requires a small amount of energy to operate the latch means, and this energy is itself only required when the latch means is released if, as is preferably the case, the latch means is at rest, i.e. is not in an actuated or energised state, when in its latched condition.

Thus, a considerable reduction in operating and maintenance costs is achieved.

Furthermore, the rate at which vehicles can negotiate a barrier according to the invention is appreciably greater than that for existing barriers since no delay is experienced in raising and lowering a barrier device. The speed of operation of a barrier according to the invention can be further increased, with a view to permitting vehicles to pass with a minimum of delay, by constructing the control means to accept payment of the prescribed fee or read a card or ticket whilst the preceding vehicle is still travelling over the platform.

In one embodiment of the invention, the step like obstruction is arranged to project above an adjacent road surface and the platform is arranged as a ramp which leads from the road surface to the top of the obstruction, when in its raised position. A fixed ramp is disposed on the opposite side of the obstruction to the platform and extends downwardly from the obstruction to the road surface in order to permit a vehicle to return to the normal road surface after it has negotiated the barrier.

In another embodiment, the barrier may be disposed in an excavation in a road or track with the top of the step-like obstruction substantially level with the adjacent road surface and the platform, when in its raised position, also substantially level with this road surface.

Preferably, the step-like obstruction and the hinged platform are prefabricated as two separate units which can be installed in juxtaposed relation, either on an existing road surface or in an excavation in the road, in order to construct the traffic barrier. For the former arrangement, the exit ramp from the barrier may be formed, for example cast, in situ, or may be manufactured as a prefabricated unit which can be installed contiguously with the rearside of the unit forming the step-like obstruction.

The control means may include a coin, token, card or ticket-operated control mechanism or device positionable in advance of the hinged platform and responsive to the insertion of one or more prescribed coins or tokens or to the scanning of a prescribed ticket or card to inhibit the latch means and thereby retain the platform locked in its raised position.The control means may also include first detecting means disposed at or adjacent the leading edge of the hinged platform and responsive to the advance of the front wheels of the vehicles towards or onto the platform, second detecting means disposed beyond, i.e. rearwardly of, the hinged platform by a distance such that it will be responsive to the front wheels of the vehicle when the latter has advanced over the platform and is no longer supported by the platform, and circuitry interconnecting the control device, the first and second detecting means, and the latch means.

The latch means is actuable by the first detecting means which is, in turn, controlled by the control device and the second detecting means. The control device is responsive to a prescribed action, such as the insertion of one or more prescribed coins or tokens, or to the scanning of a prescribed ticket or card, to inhibit or deactivate or isolate the first detecting means, as a result of which, the first detecting means will not be triggered, and will not actuate and release the latch means, in response to the advance of the front wheels of the vehicle towards or on to the hinged platform.The first detecting means will remain inhibited until the front wheels of the authorised vehicle are detected by the second detecting means, to prevent unintentional triggering of the first detecting means and resultant release of the latch means whilst the authorised vehicle is still supported by the platform. In the absence of the prescribed action, the first detecting means remains activated or enabled, and will be triggered in response to the advance of the front wheels of any authorised vehicle attempting to negotiate the barrier, resulting in actuation and release of the latch means.

When the traffic barrier is located at a site where it must allow free flow of vehicles in the reverse direction, such as, at the common entrance and exit to a car park, the control means may include auxiliary detecting means disposed rearwardly of the step-like obstruction and arranged to detect the front wheels of a vehicle travelling in the reverse direction, whereupon to inhibit the first detecting means and thereby prevent actuation of the latch means so that the latter will lock the platform in its raised position.

Thus, unhindered flow of vehicles in said reverse direction is permitted.

Both the main detecting means, i.e. the first and second detecting means, and the auxiliary detecting means, may comprise actuating means movable by the wheels of a vehicle negotiating the barrier and adapted to actuate switch means.

For example, in one embodiment, the first detecting means comprises first actuating means mounted on or in a fixed surface forming a lead-in to the hinged platform, and the second detecting means comprises second actuating means mounted on or in another fixed surface at, or forming, the exit from the barrier. The actuating means are movable by the wheels of a vehicle negotiating the barrier to actuate switch means responsive to movement of the actuating means by the front wheels of the vehicle in the manner previously described.

Preferably, the latch means comprises at least one solenoid-operated latch member mounted on the step-like obstruction and arranged to project therefrom and engage beneath a cooperating portion or detent on the platform, when the latter is in its raised position and the solenoid device is de-energized. The latch member is normally spring-biased into its projecting locking position and is retracted against the spring biassing force into its release position when the solenoid device is energised. With this arrangement, energisation of the solenoid device is only required to release the latch member when an unauthorised vehicle attempts to negotiate the barrier, so that the energy consumption of the barrier is minimised.

It will be appreciated that the latch means will fail safe in that it will automatically lock the platform in its raised position when the electrical supply is switched-off or in the event of failure of the electrical supply.

A visual signal may be associated with the barrier in order to provide the driver of a vehicle with a visible indication of whether or not the platform is locked in its raised position and the vehicle is authorised to proceed. Such a visual signal may be in the form of conventional red and green traffic lights illuminated under the control of the control means. However, in some cases, it may, alternatively or in addition, be desirable to provide an actual visible barrier in the path of travel of a vehicle negotiating the barrier, since the latter may not be apparent until unauthorised advance of a vehicle depresses the platform.

Because a driver of a vehicle normally may see nothing to prevent him from negotiating the barrier, it is possible that he may be tempted to risk driving through the barrier without first paying the appropriate fee or taking other prescribed action. Accordingly, a visible barrier member, for example, in the form of a flap or board, may be mounted on the step-like obstruction and be operable by the control means so as to move into a visible and/or obstructing position on the top of the obstruction when the latch means is released or disengaged and to return to a concealed, or substantially concealed, and/or unobstructing position when a vehicle driver has taken the prescribed action to permit him to proceed. An audible alarm may additionally or alternatively be provided.

In order that the invention may be more readily understood, reference will now be made to the accompanying drawings, in which: Fig. 1 is a plan view of one embodiment of the invention, Fig. 2 is a schematic side elevation of the embodiment shown in Fig. 1, Fig. 3 is a fragmentary cross-sectionai view, on an enlarged scale, illustrating a preferred form of the latch mechanism, Fig. 4 is a fragmentary cross-sectional view, on a more enlarged scale, illustrating the switch actuating mechanism of one of the detecting means; and Fig. 5 is a block schematic diagram of a preferred form of control circuitry for the barrier.

Referring to Figs. 1 and 2 of the drawings, the traffic barrier is shown installed on a road surface R and comprises a central barrier or obstruction unit 1 in the form of a step-like obstruction, a hinged platform unit 2 disposed ahead of the step-like obstruction, and a fixed ramp unit 3 disposed rearwardly of the obstruction. The units 1 and 2 have metal supporting frameworks, indicated schematically in outline at 4 and 5, respectively, of any suitable construction, and the sides of the frameworks may be suitably encased with cladding (not shown). The unit 1 has a top surface 6, over which a vehicle may travel, and a solid or framework front wall 7 which together form the step-like obstruction. The hinged platform unit 2 is constructed as a ramp and comprises a platform 8 hinged, at or adjacent its leading edge 9, to its supporting framework 5 by trunnions 10.The trailing edge 11 of the platform is disposed closely adjacent the front wall 7 of the step-like obstruction and the platform is rockable about the trunnions 10 from a lowered position, in which its trailing edge 11 is located adjacent the bottom of the front wall 7 to a raised position in which the trailing edge is substantially level with the top surface 6 of the obstruction.

The platform 8 is urged into its raised position by heavy duty spring means comprising doubleelliptical leaf spring units 12 located adjacent opposite sides of the platform. Each of these units comprises upper and lower elliptical leaf springs pivotally interconnected at opposite ends. The upper spring is bolted at its centre to the underside of the platform 8, and the lower spring slidably bears against the supporting framework 5 and is laterally located by guide blocks 1 2a. The double-elliptical spring units possess the advantage that they provide substantially uniform resistance over the normal range of hinging movement of the platform 8.

The platform is indexed in its raised position by a detent member comprising a tranversely extending U-section beam 1 3 secured beneath and projecting rearwardly of the trailing edge 11 of the platform, which engages underneath a transverse fixed frame member 14 of the framework of the platform unit 2 (see Fig. 3).

Mounted towards opposite sides of the obstruction unit 1 and projecting through its front wall 7 are two latch mechanisms, generally indicated at 15, which are engagable underneath the beam 13 when the latter is in abutting relation with the frame member 14, to lock the platform in its raised position, as will be more fully described hereafter. These latch mechanisms are preferably disposed approximately beneath the path of the wheels of a vehicle negotiating the barrier.

The fixed ramp unit 3 may be constructed in situ or may be prefabricated. It comprises a horizontal surface portion 1 7 contiguous with the top surface 6 of the unit 1 and leading to a downwardly extending ramp portion 18 via which vehicles travelling over the barrier return to the normal road surface R on which the barrier is installed. Short lead-in and exit or lead-out ramp sections 19, 20 are installed at the leading and trailing ends of the units 2 and 3, respectively, to afford smooth travel of a vehicle from the normal road surface R on to the barrier and vice versa.

The lead-in section 19, obstruction unit 1, fixed ramp unit 3 and lead-out section 20 are each provided with detecting means including respective pressure-sensitive switch actuators 21, 23, 22 and 24. Each actuator extends substantially across the full width of its associated unit so as to lie in the track of a vehicle travelling over the barrier. The detecting means, which will be more fully described hereafter, serve to control operation of the latch mechanisms 1 5 and signals, etc., associated with the barrier.

At the site where the barrier is installed, suitable arrangements are made (for example railings are provided) to ensure that a vehicle - travelling along the road R controlled by the barrier, from right to left, as viewed in Figs. 1 and 2, must proceed via the barrier units. The latter are made of adequate width to accommodate any vehicle expected to use the barrier. The horizontal surface at the apex of the barrier formed by the top surface 6 of the unit 1 and the contiguous surface portion 1 7 of the fixed ramp unit 3 enables the ramp units 2, 3 and, hence, the overall barrier, to be kept reasonably short, whilst providing an adequate depth for the front wall 7 of the obstruction unit 1, without risk of the underside of a vehicle wedging against the apex of the barrier.

Referring to Fig. 3, each latch mechanism 1 5 includes a latch member 25 pivotally mounted on pins 26 secured to the base of the frame of the front wall 7 of the obstruction unit 1. The latch member is actuated by a solenoid S1 disposed in a protective housing secured below the top surface of the unit 1. The latching solenoid S1 has its armature 27 linked to the pivotabie latch member 25, towards the upper end thereof, by a coupling rod 28, and a compressed coil spring 29 surrounding the armature normally urges the latter to an extended position in which the latch member 25 projects through the front wall to the position shown, limited by the engagement of a stop 25a on the latch member with a stop 7a on the front wall of the unit 1.In this position, corresponding to the deenergised condition of the solenoid So, the latch member 25 extends beneath the underside of the beam 13 at the trailing edge ii of the hinged platform to support and positively lock the latter in its raised position, and allow vehicles to pass across the barrier When the solenoid S1 is energised, the armature 27 will be retracted against the action of the spring 29, retracting the latch member 25 from beneath the beam 13, thus releasing the platform for downward hinging movement against the action of the double-elliptical spring units 12 should a vehicle attempt to pass across the barrier.

Figure 3 also shows the switch actuator 22 of the detecting means associated with the obstruction unit 1. The detecting means associated with the various ramp units and sections are effectively the same, and only the construction of the former means will therefore be described. The switch actuator 22 comprises three transversely spaced L-section members (22a, 22b and 22c in Fig. 1) only one of which, namely member 22b is visible in Fig. 3. One end of each member projects upwardly, through a bristle or brush seal device 30 or other suitable sliding seal, for engagement and depression by the wheels of a vehicle negotiating the barrier, and the other end is fixed to a transversely extending common rod 31 rotatably mounted in transversely spaced bearings, one of which is shown at 32.As shown in Fig. 4, an L-section arm 33 is fixed to one end of the rod 31, adjacent one side of the obstruction unit 1, the arm being cooperable with a switch B to actuate and close the latter when the rod 31 is rotated by depression of the actuator member 22a, 22b and/or 22c. The elements 22, 31 and 33 are normally spring biased to their position shown, and this may, for example, be achieved by one or more resilient bushes (not shown) of known type, such as bushes identifed by the trade mark "Metalastic". The or each bush is mounted on the rod 31, and has a resilient tubular element, the internal periphery of which is fixed relative to the rod 31, and the external periphery of which is fixed relative to the framework of the obstruction unit 1 in an angularly adjusted and adjustable position such that the elements normally assume their positions shown.

The operation of the barrier will now be described in conjunction with Fig. 5 which schematically illustrates one form of control circutry for the barrier. The particular circuitry illustrated is intended for controlling the barrier when installed at the entrance or exit to a car park. It includes a coin-operated switch device 34 including a coin-operated mechanism 35 and a card-operated mechanism 36, the device 34 being housed in a cubicle or meter (not shown) located ahead of the hinged platform unit 2 of the barrier, in a convenient position for insertion of the prescribed parking feed, card etc., by the driver of a vehicle wishing to negotiate the barrier.

Red and green traffic lights 37, 38 are also located in a convenient position to be observed by the driver to signal the driver whether or not the platform is locked in its raised position and he is authorised to proceed. The device 34 is connected to a convenient alternating current supply for example a conventional 240 volts mains supply. For reasons of safety, this supply terminates at the cubicle or meter, and all of the electrical components mounted in or on the barrier are supplied with 24 volts a.c. via a transformer T. When this supply is switched on to permit the barrier to operate, the various relays and switches are in their positions shown. The red traffic lights 37 are illuminated via normally closed contacts R1/4 of de-energised relay R1 connected in series with the coin/card operated switch device 34.Switches A, B and D actuable by the pressure-sensitive switch actuators 21, 22 and 24 respectively, and also the switch (not shown) actuable by actuator 23, are open. Switch A is connected in series with normally closed relay contacts R1/2 of relay R1, and with a timer Ti. The timer has normally open contacts T1/1 connected in series with relay R2, the latter relay having normally open contacts R2/2 connected in series with the mutually parallel-connected energising bridge-rectifier circuits 39 of the solenoids S1 of the latch mechanisms 15. The solenoids S1 are therefore de-energised and their associated latch members 25 lock the platform 8 in its raised position.

If a driver now attempts to drive his vehicle through the barrier without first lodging the required fee, or card, in the coin-card-operated device 34, the front wheels of the vehicle will initially contact and depress switch actuator 21 in the lead-in ramp section 19, closing switch A, and completing the energising circuit to timer T1 via closed relay contacts R1/2. Timer contacts T1/1 are immediately closed, which energises relay R2, closes relay contacts R2/2, and energises latch solenoids So, thus retracting and releasing both latch members 25. Closed contacts R2/2 also energise a flasher relay F1 which repeatedly opens and closes contacts F1/2 to intermittently illuminate a visible "REVERSE AND PAY" sign 40.

Relay contacts R2/1 are also closed and flasher unit contacts F1/1 are intermittently closed to intermittently complete a series-energising circuit to an audible alarm 41. When the front wheels pass forward over and off the switch actuator 21 of the switch A, onto the platform 8, the platform is depressed by the weight of the unauthorised vehicle compressing the spring units 12, to the position shown in broken lines in Figs. 1 and 3.

Continued advance of the vehicle will be opposed by the physical size of the obstruction presented by the front wall 7 of the step-like obstruction unit 1, and the transverse upper frame member 14 (Fig. 3) which butts against the front wall. Release and opening of the switch A starts the timer T1, and at the end of a predetermined period, the timer stops, contacts T1/1 open to de-energise relay R2, contacts R2/2 open to de-energise latch solenoids S1, and latch members 25 return to their locking positions under the effect of their return springs 29. Flasher relay F1 is also deenergised, and contacts F1/2, F1/1 and R2/1 are opened, switching off the "REVERSE AND PAY" sign 40 and the alarm 41.When the driver reverses his vehicle off the depressed platform 8, the spring units 1 2 will elevate the platform to its raised position, cammingly over-riding and momentarily depressing the latch members 25 if the timer T1 has already stopped and the latch members have consequently been returned to their locking positions.

In order to negotiate the barrier, the driver must insert the required parking fee or card in the device 34, whereupon the latter energises relay Rl,thus opening contacts R1/4 to switch off the red traffic lights 37 and closing contacts R1/3 to switch on the green traffic lights 38. In addition, contacts R1/2 open, so that when the front wheels of the vehicle pass over the switch actuator 21, and close switch A, timer T1 and latch solenoids S1 are not energised, and the latch members remain in their locked position, i.e.

switch A is effectively inhibited or isolated. The vehicle is then able to pass up the raised and locked platform 8, the momentary closing of the switch A by the rear wheels, likewise, having no effect on the timer due to the open contacts R1/2. When the front wheels run over the actuator 22 on the obstruction unit 1, the associated switch B is closed, energising relays R3 and R3A. Contacts R3/1 in parallel with switch B close to retain relays R3 and R3A energised after the wheels pass off the actuator 22, contacts R3/3 open to switch off the green traffic lights 38, contacts R3A/2 close to switch on the red traffic lights 37, and contacts R3/2 close to enable switch D of actuator 24 of the lead-out ramp section 20.The front wheels of the vehicle next pass over actuator 23 to close an associated switch (not shown) which serves to condition the coin/card operated device 34 to accept the parking fee or card of the driver of the next vehicle. This switch, instead of switch B, could alternatively serve to control relay R3 and enable switch D.

As the vehicle leaves the barrier, its front wheels momentarily pass over actuator 24 in lead-out ramp section 20, which closes associated switch D, energising relay R4.

Contacts R4/1 and R4/2 associated with the coin/card-operated device 34 are opened, deenergising relay R1 which resets the barrier control circuitry or system to its initial condition.

When the front wheels of the vehicle actuate the actuator 22 on the obstruction unit 1 and enable the switch D, it will be apparent that the rear wheels of the vehicle will still be supported by the platform 8. If, at this stage, the switch D is closed and enables switch A, for example by the rears wheels of the preceding vehicle passing over the actuator 24 of the lead-out ramp section 20 as the vehicle leaves the barrier, or by a person treading on the actuator 24, and if the switch A is then closed, for example by the front wheels of an unauthorised vehicle passing over the actuator 21 of the lead-in section 1 9, or by a person treading on the actuator 21, the latch solenoid-energising circuit will be completed.However, the arrangement, for example the power or strength exerted by the solenoids S1, and/or the design or configuration of the latch means and detent member, is such that the weight of the vehicle applied via its rear wheels to the platform 8 will press the detent member or beam 13 (Fig. 3) down onto the latch members 25 with sufficient -force to over-ride the solenoids and ensure that the latch members 25 cannot move to their retracted positions until the rear wheels of the authorised vehicle pass off the platform 8 onto the top of the obstruction unit 1 and said force is removed. If, at that stage, the front wheels of a succeeding unauthorised vehicle are already on the platform 8, the weight of the latter will likewise prevent the latch members from releasing.However, the length of the platform 8 is arranged to be less than the minimum wheel-base of the normal range of vehicles intended to use the barrier. Thus, as the front wheels of the unauthorised vehicle pass onto the top of the obstruction unit 1, the rear wheels thereof will not have reached the leading-edge of the platform 8, the pressure on the platform will be removed, and the latch members will retract, trapping the unauthorised vehicle spanning the released platform 8.

The coin/card operated device 34 is also associated with a counter 42 which, via relay contacts R1/1, counts the number of authorised vehicles passing through the barrier. This number is compared, in an appropriate manner, with the number of vehicles leaving the parking zone, to derive a count corresponding to the instantaneous total number of parked vehicles. When the parking zone is full, a further red light 43 indicating this fact is illuminated.

It is desirable that the barrier should be capable of operating as rapidly as possible so as to allow vehicles to passing with minimum delay. The maximum speed of operation of the barrier can be increased by enabling prepayment of the parking fee while the preceding vehicle is still advancing over the platform 8. It is customary to operate existing car park barriers with what is commonly known in the art as a coin verifier or coin rejector.

In such equipment, the coins inserted into the parking meter travel down an inclined chute into the coin verifier. The device 34 may include a coin verifier of known type but modified so that, as soon as the coins energise the relays Ri and R1A, upon successfully passing through the verifier, an auxiliary switch is arrange to actuate a gate in the coin chute which then enables coins to be lodged in the chute by the next vehicle driver. At the moment the preceding vehicle triggers the switch D to enable the switch A, the auxiliary switch also operates and opens the gate to permit the coins to enter the verifier, whereupon the switch A is again inhibited. The next vehicle can therefore commence to advance over the hinged platform before the preceding vehicle has completely negotiated the barrier.

In cases where the traffic light signals 37, 38 are not considered a sufficient guide or deterrent to prevent the driver of a vehicle from attempting to negotiate the barrier, a visible, physical barrier may be provided. In the embodiment illustrated in Figs. 1 and 2, this takes the form of a plate or board 44 provided with suitable markings to enhance its visibility and mounted on and to one side of the obstruction unit 1. The board 44 is mounted for swinging movement about a vertical axis, and is normally spring-biassed into a closed position in which it projects part way across the unit 1 as shown in Fig. 1, where it is visible to a vehicle driver. The board 44 may be swung out of the way by a solenoid S2 connected in series with relay contacts R1/3 so as to be energised when relay R1 is energised.Alternatively, the board 44 could be normally biassed into its open position, and only swung closed when its solenoid S2 is energised, for example by closure of the switch A when enabled, by an unauthorised vehicle.

In some installations, the barrier may be required to control the flow of vehicles in one direction whilst permitting free flow of vehicles in the reverse direction, for example, as in a car park having a single road or track for both entrance and exit to the car park. At least the actuator 23 on the fixed ramp unit 3 may, in this event, be utilized as the auxiliary detecting means required to provide this facility. Hence, for movement of vehicles from right to left, as viewed in these figures, the barrier operates as previously described. However, the barrier must permit free flow of traffic in the reverse direction, that is from left to right, and, when a vehicle travels across the barrier in this direction, the platform 8 must therefore remain locked in its raised position.This may be achieved by using the actuator 23 to inhibit, i.e. isolate or open-circuit, the switch A, and the lead-in actuator 21 and/or a timer to enable switch A and reset the system, when the rear wheels of the vehicle have passed off the platform 8.

Whilst particular embodiments have been described, it will be understood that modifications can be made without departing from the scope of the present invention. For example, the detecting means including the switch B and associated actuator 22, and/or associated circuitry, may be operable to reset the system, i.e. enable the switch A, when the rear wheels of the authorised vehicle advancing through the barrier pass over and actuate the actuator 22. For example, the first actuation of the actuator 22, which will be effected by the front wheels of the vehicle, may serve to switch the traffic lights from green to red, whilst the second actuation of the actuator 22, which will be effected by the rear wheels, may serve to enable the switch A.

The secondary barrier or board 44 may be omitted, or replaced by a solenoid-actuated board hingedly mounted in a cavity in the top surface of the obstruction unit 1, which may be pivoted to project upwardly from the top surface until the coin/card operated device 34 is operated, or when the switch A is enabled and closed.

Claims (filed 6/4/82) 1. A traffic barrier comprising a step-like obstruction adapted to resist or prohibit the passage of a vehicle, a hinged platform disposed in advance of the step-like obstruction and rockable between a lowered position and a raised position, in which its trailing edge is adjacent the top of the step-like obstruction, and means urging the platform into its raised position, characterised by the platform being depressible into its lowered position by a vehicle advancing over said platform from its leading to its trailing edge, whereby the obstruction is presented to the vehicle to resist its advance, latch means operable normally to lock the platform in its raised position, and control means for selectively actuating the latch means, whereby the platform is normally locked in its raised position to permit a vehicle to advance over the obstruction from the platform, said control means being responsive to advance of a vehicle towards the obstruction to release the latch means.

2. A traffic barrier as claimed in claim 1, wherein said control means is responsive to advance of the front wheels of an unauthorised vehicle relative to the platform to release the latch means.

3. A traffic barrier as claimed in claim 1 or 2, wherein said control means includes a manually operable device positioned in advance of the platform and responsive to a prescribed action to inhibit release of the latch means responsive to advance relative to the platform of the front wheels of a vehicle authorised by said prescribed action, release of the latch means being enabled by means responsive to advance of wheels of said vehicle beyond the platform.

4. A traffic barrier as claimed in claim 3, wherein said control means includes detecting means comprising first actuating means disposed at or in advance of the leading edge of the platform, and actuable by the front wheels of a vehicle approaching the platform to actuate first switch means, means operable selectively to inhibit the first switch means whereby actuation

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

Claims (9)

**WARNING** start of CLMS field may overlap end of DESC **. known in the art as a coin verifier or coin rejector. In such equipment, the coins inserted into the parking meter travel down an inclined chute into the coin verifier. The device 34 may include a coin verifier of known type but modified so that, as soon as the coins energise the relays Ri and R1A, upon successfully passing through the verifier, an auxiliary switch is arrange to actuate a gate in the coin chute which then enables coins to be lodged in the chute by the next vehicle driver. At the moment the preceding vehicle triggers the switch D to enable the switch A, the auxiliary switch also operates and opens the gate to permit the coins to enter the verifier, whereupon the switch A is again inhibited. The next vehicle can therefore commence to advance over the hinged platform before the preceding vehicle has completely negotiated the barrier. In cases where the traffic light signals 37, 38 are not considered a sufficient guide or deterrent to prevent the driver of a vehicle from attempting to negotiate the barrier, a visible, physical barrier may be provided. In the embodiment illustrated in Figs. 1 and 2, this takes the form of a plate or board 44 provided with suitable markings to enhance its visibility and mounted on and to one side of the obstruction unit 1. The board 44 is mounted for swinging movement about a vertical axis, and is normally spring-biassed into a closed position in which it projects part way across the unit 1 as shown in Fig. 1, where it is visible to a vehicle driver. The board 44 may be swung out of the way by a solenoid S2 connected in series with relay contacts R1/3 so as to be energised when relay R1 is energised.Alternatively, the board 44 could be normally biassed into its open position, and only swung closed when its solenoid S2 is energised, for example by closure of the switch A when enabled, by an unauthorised vehicle. In some installations, the barrier may be required to control the flow of vehicles in one direction whilst permitting free flow of vehicles in the reverse direction, for example, as in a car park having a single road or track for both entrance and exit to the car park. At least the actuator 23 on the fixed ramp unit 3 may, in this event, be utilized as the auxiliary detecting means required to provide this facility. Hence, for movement of vehicles from right to left, as viewed in these figures, the barrier operates as previously described. However, the barrier must permit free flow of traffic in the reverse direction, that is from left to right, and, when a vehicle travels across the barrier in this direction, the platform 8 must therefore remain locked in its raised position.This may be achieved by using the actuator 23 to inhibit, i.e. isolate or open-circuit, the switch A, and the lead-in actuator 21 and/or a timer to enable switch A and reset the system, when the rear wheels of the vehicle have passed off the platform 8. Whilst particular embodiments have been described, it will be understood that modifications can be made without departing from the scope of the present invention. For example, the detecting means including the switch B and associated actuator 22, and/or associated circuitry, may be operable to reset the system, i.e. enable the switch A, when the rear wheels of the authorised vehicle advancing through the barrier pass over and actuate the actuator 22. For example, the first actuation of the actuator 22, which will be effected by the front wheels of the vehicle, may serve to switch the traffic lights from green to red, whilst the second actuation of the actuator 22, which will be effected by the rear wheels, may serve to enable the switch A. The secondary barrier or board 44 may be omitted, or replaced by a solenoid-actuated board hingedly mounted in a cavity in the top surface of the obstruction unit 1, which may be pivoted to project upwardly from the top surface until the coin/card operated device 34 is operated, or when the switch A is enabled and closed. Claims (filed 6/4/82)

1. A traffic barrier comprising a step-like obstruction adapted to resist or prohibit the passage of a vehicle, a hinged platform disposed in advance of the step-like obstruction and rockable between a lowered position and a raised position, in which its trailing edge is adjacent the top of the step-like obstruction, and means urging the platform into its raised position, characterised by the platform being depressible into its lowered position by a vehicle advancing over said platform from its leading to its trailing edge, whereby the obstruction is presented to the vehicle to resist its advance, latch means operable normally to lock the platform in its raised position, and control means for selectively actuating the latch means, whereby the platform is normally locked in its raised position to permit a vehicle to advance over the obstruction from the platform, said control means being responsive to advance of a vehicle towards the obstruction to release the latch means.

2. A traffic barrier as claimed in claim 1, wherein said control means is responsive to advance of the front wheels of an unauthorised vehicle relative to the platform to release the latch means.

3. A traffic barrier as claimed in claim 1 or 2, wherein said control means includes a manually operable device positioned in advance of the platform and responsive to a prescribed action to inhibit release of the latch means responsive to advance relative to the platform of the front wheels of a vehicle authorised by said prescribed action, release of the latch means being enabled by means responsive to advance of wheels of said vehicle beyond the platform.

4. A traffic barrier as claimed in claim 3, wherein said control means includes detecting means comprising first actuating means disposed at or in advance of the leading edge of the platform, and actuable by the front wheels of a vehicle approaching the platform to actuate first switch means, means operable selectively to inhibit the first switch means whereby actuation

of the first switch means will not actuate and retract the latch means from the locking position, and to enable the first switch means whereby actuation of the first switch means will actuate and retract the latch means to the release position, further actuating means disposed rearwardly of the platform and actuable by the front wheels of a vehicle leaving the platform to actuate further switch means, actuation of the further switch means being operable to cause the inhibit/enable means to enable the first switch means.

5. A traffic barrier as claimed in claim 4, wherein the inhibit/enable means comprises switch means connected in series with the first switch means.

6. A traffic barrier as claimed in claim 4 or 5, wherein said further actuating means comprises second actuating means mounted on or rearwardly of the obstruction and operable to actuate second switch means, and third actuating means mounted rearwardly of the second actuating means and operable to actuate third switch means, actuation of the second switch means being operable to change the third switch means from an inhibited to an enabled state, actuation of the third switch means, when enabled, being operable to cause the inhibit/enable means to enable the first switch means.

7. A traffic barrier as claimed in any preceding claim, wherein the latch means is carried by the obstruction, and comprises at least one pivotally mounted latch member, spring means normally biasing the latch member to the locking position in which it engages detent means on the platform, and a solenoid device which, when actuated, retracts the latch member from the locking position to the release position in which it is disengaged from the detent means, against the biasing force of the spring means.

8. A traffic barrier as claimed in any preceding claim, wherein said means urging said platform into the raised position comprises at least one pair of opposed, semi-elliptical leaf springs, interconnected at their opposite ends, and being loaded intermediate their ends by the platform.

9. A traffic barrier as claimed in any preceding claim, wherein said step-like obstruction is adapted to project above an adjacent road surface, and the platform, when in the raised position thereof, is arranged as a ramp which leads from the road surface to the top of the obstruction, and wherein a fixed ramp is disposed on the opposite side of the obstruction from the platform and extends downwardly from the obstruction to the road surface in order to permit a vehicle to return to the normal road surface after it has negotiated the barrier.

1 0. A traffic barrier substantially as hereinbefore described with reference to the accompanying drawings.