Self-Contained Solar Powered Removable Bollard

FIELD

[001] This invention relates to the field of safety barriers, in particular, removable barriers restricting vehicular access to areas.

BACKGROUND

[002] Bollards are a useful method of restricting traffic to certain areas. Most

bollards are a substantially cylindrical body with a portion buried or secured in the ground, with the remaining protruding vertically. The bigger and stronger the bollard the great the force it can resist. Smaller bollards can restrict small vehicles like motorcycles and small automobiles. Larger bollards can be designed to withstand the force of collision from larger automobiles and trucks. However, installing bollards in public areas may restrict access to areas where certain vehicles are required to access periodically. For example, installing bollards in a public space may restrict access to trash collection and maintenance vehicles. One solution is to temporarily retract bollards to allow access into restricted areas.

[003] Another challenge with bollards is the cost and complexity of installation.

Bollards designed to resist impact generally require a solid footing, involving the installation of reinforced concrete bases and other structures.

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(Rule 26) RO/AU PRIOR ART

[004] Solutions exist in the public domain that allow a bollard to be removed or retracted. Removable bollards are generally simple tubes secured in place using a mechanical locking system. Most are small enough for one or two people to carry. However, smaller bollards cannot stop larger vehicles such as cars and trucks. Larger bollards can be fitted with retraction mechanisms.

[005] US7244075B2 discloses a telescopic retractable bollard with a screw jack however the screw mechanism is activated by an external force such as a drill or manual handle. This require manual handling each time the bollard is raised or lowered.

[006] AU 2007201272 Al discloses a motorised retractable bollard however the control systems are installed outside the bollard, requiring installation of external wiring to support the operation of the bollard. This conventional method incurs substantial cost of equipment, installation and maintenance.

[007] US6412235B1 by J T Pylant discloses a method of a screw-type, in-ground anchor for anchoring an above ground upright. Whilst screw-pilings and 'ground screws" have been utilised since the mid-1800s, they have been generally used to support a fixed, vertical, above ground structures. This invention combines the prior art in ground screws with the new retractable bollard in a new method by making the outer housing of the bollard itself a ground screw, thereby removing the requirement for installation of support structures such as concrete footings.

SUMMARY OF INVENTION

[008] Technical Problem

Existing retractable bollard systems require a separate controller, electrical mains supply, sensors, wiring and actuation systems to operate. This results in considerable installation and maintenance costs and complexity.

[009] Existing methods of bollard installation require fixed structures to retain the bollard and withstand the force of impacts.

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(Rule 26) RO/AU [0010] Solution to Problem

This invention discloses apparatus and systems that allow bollards to be electrically retracted without the cost of installing external supporting equipment. The solution is to house all the complex components of the bollard into the inner barrier member. This includes the power source, solar charger, electronic controller, communications link, electromechanical actuator, and sensors. This invention also discloses methods to support a self-contained retractable bollard that allows a battery powered device to lift a wide range of bollard sizes and weights.

[001 1 ] This invention also discloses a design of the retractable bollard that allows the external bollard body to be secured into the ground as a single screw, eliminating the need to prepare the footing with fixed structures.

[0012] Advantageous Effects of Invention

This invention allows any size bollard to be retractable with minimal installation labour and materials, and reduced ground preparation (civil works).

[0013] Bollards using this invention are lower cost to deploy due to reduced

installation requirements.

[0014] By containing all the complex and components in the moveable barrier

member, servicing costs can be reduced by allowing bollards to be exchanged in the field and serviced in a workshop.

BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 : cross-section view of the main components depicting the bollard in a partially retracted view

[0016] The outer housing (1 ) is secured in the ground. The inner barrier member (2) moves longitudinally inside the outer housing. A photovoltaic cell (3) is mounted on the top plane of the bollard. An electric motor (4) through a worm drive or similar assembly drives a screw (5) which moves a nut (6) along the screw, causing the bollard to move in the longitudinal axis.

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(Rule 26) RO/AU The conical section (7) and screw flights (8) are connected to the outer housing.

[0017] DESCRIPTION OF EMBODIMENTS

[0018] The following description is provided by way of example only with reference to the preferred embodiments which is not intended to limit the scope of the invention.

[0019] In the preferred embodiment, a fixed outer housing (1 ) is secured into the ground by rotating the member with downward force. The screw flights (8) draw the outer housing into the ground and the conical shape (7) from the bottom tip of the outer housing to the main body compacts the soil around the outer housing.

[0020] In an alternative embodiment, the outer housing can be secured by

conventional methods such as being directly buried in the ground, with or without the addition of concrete.

[0021 ] The outer housing is substantially round, with a key or notch to allow the inner barrier member to rotationally align to whilst raising and lowering.

[0022] In another embodiment, the outer housing contains a shaped or geometry such that the inner barrier member or part of the barrier member, of a similar geometry, can slide inside without rotating. For example, the outer housing and barrier member may be shaped in the form of an oval or rectangle or other profile.

[0023] A shaft is secured to the base of the outer housing and extends up along the longitudinal axis but remains below the top of the outer housing. To this shaft is secured the nut component of the screw jack assembly.

[0024] The inside barrier member (bollard) is shaped such that it can slide along the longitudinal axis of the outer housing without twisting. If it is substantially cylindrical a key or notch can be used to prevent it from twisting throughout its range of travel.

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(Rule 26) RO/AU [0025] A photovoltaic array mounted on the top of the bollard converts sunlight to electricity which is used to charge the batteries also mounted in the bollard. A charging regulator inside the bollard monitors the charging process and disconnects the battery when charging is complete. The surface area available for the photovoltaic cell is relatively small compared to the power required to drive the bollard, so power is stored in an electric storage device (battery). This accumulated power can be used to drive a bollard system weighing several hundred kilograms with the appropriate gearing ratio.

[0026] An electric motor is mounted internally to the bollard. The output of the motor is connected to worm gear or other reduction assembly. The electric actuator assembly housed within the barrier member provides mechanical force to cause the barrier member to move between the retracted and extended positions relative to the outer housing. The resistance of the worm gear assembly prevents the output of assembly from reverse driving the motor, in situations where the bollard is heavy.

[0027] In the preferred embodiment the output of the gear assembly is connected to the screw that forms the screw jack assembly. The screw is supported by a thrust bearing which allows the screw to turn freely relative to the bollard, but remains captive within the bearing assembly, and moves with the bollard. The screw drive ordinarily is connected to the nut, completing the screw jack assembly.

[0028] When the motor turns in one direction, the screw turns, and the nut, moving along the screw, pushes the bollard in one direction along the longitudinal axis. Reversing the direction of the motor reverses the direction of the bollard motion.

[0029] In another embodiment the positions of the screw and nut are inverted, where the nut of the screw jack is mated to the inner barrier member, and the threaded shaft is fixably related to the outer fixed member.

[0030] In other embodiments the actuation may drive a rack and pinion system, pressurised gas system, hydraulic system or other power transfer means known to those skilled in the art. New and different methods of power transfer can implemented without departing from the intent of the invention, which is to

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(Rule 26) RO/AU contain the complex motion generating components within the barrier member.

[0031 ] An electronic system controller is housed inside the barrier member. The

electronic system controller switches power between the storage device and the motor to control the speed and direction of the electric motor.

[0032] The electronic system controller contains an internal time reference and a schedule of times and dates where the bollard should be raised or lowered. At the programmed times, the bollard is raised and lowered by the electronic system controller.

[0033] Limit sensors connected to the extreme limits of range of the bollard send signals to the electronic controller when the bollard is extended or retracted. Rotary encoders or rotation sensors may also be used to signal the number of rotations to the electronic controller. Using the number of rotations, the controller determines the position of the bollard throughout its range.

[0034] If the bollard is moved, or slips outside its scheduled parameters, a message is sent to a remote computer.

[0035] To conserve electricity, the electronic controller executes sleep/wake cycles where it shuts down (sleeps) and periodically powers up (wakes) to check if there are alarm conditions, or instructions from sources such as an RFID card present, or a command from a remote user across a network.

[0036] The electronic controller may change the period of sleep and time awake

based on a schedule saved in computer memory. Preferentially this schedule should reflect the periods where the bollard is likely to be controlled. For example, at night the sleep period may be 5 seconds, while during daytime the sleep cycle may be 3 seconds. The controller may selectively power peripheral devices and sensors on and off according to separate schedules to further save power consumption.

[0037] In the preferred embodiment the bollard operates in stand-alone mode,

requiring minimal communications with external systems. However, from time to time communications with a remote computer may be desirable. This may be to receive remote override commands to raise/lower the bollard, synchronise the internal clock, update stored schedule and user parameters, or send alarms and information relating to the condition of the bollard. There

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(Rule 26) RO/AU are many methods of wirelessly communicating data know to those skilled in the art. These include radio frequency, and electro-optical transceivers using various ranges of the electromagnetic spectrum. Any combination of these wireless communications means can be used without deviating from the scope of this invention.

[0038] In many situation, local manual override of the bollard controls is desirable.

For instance, a bollard may be programmed to be raised, but an ad-hoc situation may require it to be lowered. This invention discloses a number of methods to "wake" the bollard from its sleep and receive the commands.

[0039] A vibration sensor mounted on the inner barrier member serves the role of an alarm sensor when the bollard is impacted, causing an alarm message to be sent. This same type of sensor may also be used to wake the electronic system controller from a programmed sleep period. When a vibration exceeding a designed threshold is detected, the sensor triggers the electronic system controller to "awaken".

[0040] A magnetic sensor is installed on the barrier member. If a correctly aligned magnet is detected, this sensor triggers the bollard to awaken from its sleep cycle.

[0041 ] In the normal operation of retractable bollards, it is preferential for the system controller to receive feedback on the barrier member's position relative to the outer fixed member.

[0042] This invention discloses methods and apparatus of a retractable bollard that allow it to be installed and uninstalled with ease, whilst maintaining device security.

[0043] The outer fixed member is first installed in the ground. The barrier member is then placed on the outer member. The two members are aligned by either the shape of the bollard and/or the notches and keys (if present).

[0044] In an embodiment the shaft of the barrier member rests on the fixed nut

connected to the outer fixed member. Initially, the bollard is overextended and not secured in place. A signal from a sensor or remote device activates the motor, which drives the screw in a direction which engages the nut, and pulls the bollard down into the housing, securing the bollard. The motor stops when the retract limit switch is activated, the number of revolutions counted is

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(Rule 26) RO/AU exceeded, or when the motor current is detected as exceeding the preconfigured threshold. The bollard is now in the retracted position and the top of the bollard should be substantially level with the top of the outer housing.

[0045] If the electronic controller receives a command to extend the bollard, it

activates the motor in the extend direction until either the extend limit switch is triggered, and/or the number of revolutions counted is exceeded. The extended position leaves the screw jack's nut and shaft still connected, so the bollard cannot be removed or forced further.

[0046] If the electronic controller receives a command to retract the bollard, it

activates the motor in the retract direction until either the retract limit switch is triggered, and/or the number of revolutions counted is exceeded.

[0047] If the electronic controller receives a "remove" command, it activates the

motor in the extend direction, ignoring the extend limit switch and revolutions count. This disengages the screw from the fixed nut, allowing the bollard to be removed.

Citation List

US7244075B2 Telescopic bollard with screw drive

AU 2007201272 Al A retractable bollard

US6412235B1 Removable screw-type, in-ground anchor device

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(Rule 26) RO/AU