A gate actuator and a closure system comprising the same

Abstract

A gate actuator (3) comprising an elongated housing configured to be mounted to the support of a closure system. The electrical circuit of the gate actuator comprises a first part circuit (31) and a second part circuit (32) wherein the first part circuit is electrically connected to the second part circuit via a diode 50. The second part circuit comprises a motor control circuit (100), electrically connected to a conductive path subsequent the diode at the motor side voltage (215) to control the DC electromotor, and a brake resistor circuit (200) also electrically connected to a conductive path subsequent the diode at the motor side voltage (215). The gate actuator further comprises an external load resistor electrically connected to the brake resistor circuit (200), wherein a first connection of the external load resistor is connected to a conductive path subsequent the diode at the motor side voltage (215) and wherein the brake resistor circuit (200) is configured to activate the external load resistor when the motor side voltage (215) reaches a first predetermined voltage.

Description

[0001] A gate actuator and a closure system comprising the same

[0002] Technical field

[0003] The present invention generally relates to a gate actuator for opening and closing a closure system having a support and a closure member which are hingedly connected to each other. The present invention further relates to a closure system comprising the gate actuator.

[0004] Background art

[0005] Various types of gate actuators are known in the art, for example spring-biased gate actuators as disclosed in WO 2012 / 103572; hydraulically damped spring-biased gate actuators as disclosed in WO 2018 / 228729; and motorized gate actuators as disclosed in WO 2019 / 048359. The present invention is generally related to gate actuators of the latter kind which are operated by an electromotor.

[0006] The gate closer disclosed in WO 2019 / 048359 comprises: an elongated housing configured to be mounted against a support, the elongated housing extending in a longitudinal direction between a first end and a second end; an electromotor mounted in the housing, the electromotor having an output shaft near the first end of the elongated housing and which is rotatable around said longitudinal direction in a first rotational direction upon activation of the electromotor; and a driver operatively connected to the output shaft (i.e. by being connected to the eyebolt hinge), the driver being configured to urge the closure member to its closed position upon rotation of the output shaft in said first rotational direction.

[0007] In the gate closer of WO 2019 / 048359, the driver is directly fixed on the output shaft of the electromotor. Whilst this provides a very compact design, there is a risk of damaging the electromotor when the gate undergoes a sudden directional change. For example, when the gate is closing, a user may appear who wishes to pass through the gateway and thus pushes against the closing gate. This force requires a very sudden reversal of the electromotor rotation direction. Such sudden reversals are a known cause of damage to the electromotor.

[0008] Another problem with this type of gate actuators is that the electromotors may generate energy when someone is pushing on the closing member. This energy is running into the electrical circuit of the gate actuator where it may cause damage to the electronics.

[0009] Disclosure of the invention

[0010] It is an aim of the present invention to provide an improved gate actuator.

[0011] To his aim the gate actuator according to the invention comprises an elongated housing configured to be mounted to the support, the elongated housing extending in a longitudinal direction between a first end and a second end, a DC electromotor mounted in the housing, the electromotor having an output shaft near the first end of the elongated housing and which is rotatable around said longitudinal direction upon activation of the electromotor or upon rotation of the closure member, a driver operatively connected to the output shaft, the driver being configured to rotate the closure member upon rotation of the output shaft and to rotate the shaft upon rotation of the closure member, and a printed circuit board mounted in the housing and comprising an electrical circuit, wherein the electrical circuit is electrically connected to the DC electromotor to control the DC electromotor, wherein the electrical circuit comprises a first part circuit and a second part circuit, wherein the first part circuit is electrically connected to the second part circuit via a diode, wherein the diode is conducting from the first part circuit to the second part circuit providing a motor side voltage in the second part circuit at a location subsequent the diode, wherein the second part circuit comprises a motor control circuit electrically connected to a conductive path subsequent the diode at the motor side voltage to control the DC electromotor, wherein the motor control circuit comprises at least one mosfet, and a brake resistor circuit electrically connected to a conductive path subsequent the diode at the motor side voltage, and wherein the gate actuator further comprises an external load resistor electrically connected to the brake resistor circuit of the printed circuit board, wherein a first connection of the external load resistor is connected to a conductive path subsequent the diode at the motor side voltage and wherein the brake resistor circuit is configured to activate the external load resistor when the motor side voltage reaches a first predetermined voltage.

[0012] This gate actuator ensures that any energy which is generated by the electromotor is controlled. Firstly, by dividing the electrical circuit in a first part circuit and a second part circuit with a diode in between the two parts, any critical component in the electrical circuit which are located in the first part circuit will never face any voltage increase in the system by the electromotor. Secondly, the second part circuit ensures that when the voltage in the second part reaches a predetermined voltage, an external load resister is activated which consumes energy and therefor will lower the voltage in the second part circuit.

[0013] In some embodiments of the invention, the brake resistor circuit is configured to activate the external load resistor when the gate actuator is not powered and the motor side voltage reaches a second predetermined voltage.

[0014] This functionality foresees in safe operation of the gate actuator when there is no power. There are many reasons why a gate actuator may have no power. There can be a power break, the power may not be switched on, the transfo may be broken, etc. When this happens and someone pushes on the closing member generating energy which runs into the electronics of the gate actuator, the structure ensures that the external load resistor is active and the external load resistor will consume energy to lower the voltage in the circuit.

[0015] In some embodiments of the invention, the brake resistor circuit further comprises a one-bit memory element comprising an output pin wherein the one-bit memory element is configured to provide at the output pin 0V when no voltage is received at other pins of the one-bit memory element, a Zener diode having a cathode pin and an anode pin and which is electrically connected at the cathode pin to the motor side voltage and the output pin of the one-bit memory element, wherein the Zener diode is configured to stabilize the motor side voltage to a third predetermined voltage at a conductive path in the circuit in direct electrical contact with the cathode pin of the Zener diode when the motor side voltage is at least equal to the third predetermined voltage, a mosfet electrically connected to the Zener diode, wherein the mosfet is at its other pins electrically connected to the motor side voltage and to ground, wherein conductive path between the motor side voltage and the mosfet is configured to conduct current through the external load resistor, and the mosfet is configured to conduct when the second predetermined voltage at the Zener diode is reached causing that the external load resister to consume energy when the gate actuator is not powered and the motor side voltage reaches the second predetermined voltage.

[0016] This structure also foresees in safe operation of the gate actuator when there is no power. The structure ensures that the external load resistor is active when a certain predetermined voltage is reached. And, once the external load resistor is activated, it will consume energy to lower the voltage in the circuit.

[0017] In some embodiments of the invention, the brake resistor circuit further comprises a PNP transistor, which has a Base pin at 24V, an Emitter pin electrically connected to the motor side voltage and a Collector pin electrically connected to Ground, and a fourth resistor which creates a first voltage in the conductive path before the resistor when the PNP transistor is conducting, wherein the resistance value of the fourth resistor determines the first predetermined value.

[0018] By this structure the predetermined value can be chosen during design of the electronic board in function of the components on the board.

[0019] In some embodiments of the invention, the fourth resistor is 22 KOhm and the first predetermined value is 47,4 V. By this selection of the value of the resistor, there is an advantageous balance between minimizing energy in the electronics and activation time of the external load resistor.

[0020] In some embodiments of the invention, the brake resistor circuit comprises a comparator, which has a IN+ pin electrically connected to a reference voltage supply, wherein the voltage value of the reference voltage supply determines the first predetermined value.

[0021] By this structure the predetermined value at which the external load resistor is activated can be optimized by optimizing the choice for the voltage supply of the comparator which determines the voltage at the IN+ pin.

[0022] In some embodiments of the invention, the reference voltage supply is 2,5V and the first predetermined value is 47,4 V.

[0023] By this selection of the value voltage at the IN+ pin of the comparator, there is an advantageous balance between minimizing energy in the electronics and the amount of time that the external load resistor needs to be activated.

[0024] In some embodiments of the invention, the brake resistor circuit comprises a Schmitt trigger electrically connected to an Output pin of the comparator.

[0025] This avoids any malfunction of the gate actuator due to noise or fluctuations in the electric circuit.

[0026] In some embodiments of the invention, the brake resistor circuit comprises a one-bit memory element.

[0027] The one-bit memory element ensures that the load resister can be deactivated.

[0028] In some embodiments of the invention, the brake resistor circuit comprises a one-bit memory element which has a memory element Q pin as output, a CLK pin for receiving a clock signal from a controller and a memory element D pin as input, wherein the one-bit memory element copies data from the memory element D pin to the memory element Q pin when a clock pulse is seen at the CLK pin. This more specific one-bit element also ensures that the load resister can be deactivated.

[0029] In some embodiments of the invention, the one-bit memory element is a D flip-flop.

[0030] By using a D flip-flop the external load resister can be deactivated and the circuit can be structured such that the external load resistor can not be deactivated if the motor side voltage is not lower than a predetermined threshold.

[0031] In some embodiments of the invention, the brake resistor circuit comprises a NPN transistor, which has a NPN Base pin, a NPN Emitter pin electrically connected to ground and a NPN Collector pin electrically connected to a conductive path in the circuit, wherein the brake resistor circuit is configured to control the voltage in the conductive path in the circuit in direct electrical connection with the NPN Collector pin by controlling the voltage at the NPN Base pin of the NPN transistor.

[0032] The use of this NPN transistor allows a stable configuration of activating and deactivating the external load resistor.

[0033] In some embodiments of the invention, the brake resistor circuit comprises a Zener diode having a cathode pin and an anode pin, wherein the Zener diode which is electrically connected at the cathode pin to the motor side voltage and the NPN Collector pin of the NPN transistor, wherein the Zener diode is configured to stabilize the motor side voltage to a Zener voltage at a conductive path in the circuit in direct electrical contact with the cathode pin of the Zener diode when the NPN transistor is not activated.

[0034] This structure further ensures a stable activating and deactivating of the external load resister. This structure also ensures that the external load resister will consume energy when the gate actuator is not powered.

[0035] In some embodiments of the invention, the brake resistor circuit comprises a mosfet which has a gate pin, a source pin and a drain pin, wherein the drain pin is electrically connected to a second connection of the external load resistor, wherein the source pin is electrically connected to ground, and wherein the brake resistor circuit is configured to provide a voltage at the gate pin of the mosfet which is higher than a threshold voltage value of the mosfet when the motor side voltage reaches the first predetermined voltage.

[0036] This structure ensures a safe and reliable activating and deactivating of the external load resistor. This structure also ensures that the external load resistor is consuming energy when the gate actuator is not powered as soon as the motor side voltage is higher than the mosfet threshold voltage.

[0037] In some embodiments, the gate pin of the mosfet is electrically connected to the conductive path in the circuit in direct electrical contact with the cathode pin of the Zener diode, and the brake resistor circuit is configured that the voltage at the gate pin of the mosfet is the same as the voltage at the conductive path in the circuit in direct electrical contact with the cathode pin of the Zener diode.

[0038] This structure ensures a stable and reliable activating and deactivating of the external load resistor.

[0039] In some embodiments of the invention, the brake resistor circuit comprises a controller, wherein the controller is electrically connected to the brake resistor circuit to receive a signal, and wherein the controller is configured to determine if the external load resistor is activated based on the signal.

[0040] This structure ensures that the controller can take any action based on the correct status of the external load resistor.

[0041] In some embodiments, the controller is configured to measure the motor side voltage, and the controller is configured to deactivate the external load resistor when the motor side voltage is lowered below a fourth predetermined value.

[0042] This structure ensures safe operation under the control of the controller.

[0043] In some embodiments, the brake resistor circuit is configured to deactivate the external load resistor by switching the D flip-flop. This structure ensures that the controller is controlling the deactivation of the external load resistor while taking into account the motor side voltage.

[0044] In some embodiments, the printed circuit board comprises a controller, wherein the controller is configured to control a clock signal to the CLK pin, and wherein the brker resistor circuit is configured such that the controller cannot deactivate the external load resistor when the motor side voltage is higher than the first predetermined value.

[0045] This structure ensures safety. The controller cannot deactivate the external load resistor is the motor side voltage is still too high. The hardware situation prevails on any instruction by the software to deactivate.

[0046] In some embodiments of the invention, the voltage at the CLR pin of the D flip-flop is lower than the D flip-flop threshold voltage value of the D flip-flop when the motor side voltage is higher than the first predetermined value.

[0047] This structure causes safety by the hardware. The hardware ensures that the motor side voltage is low enough before a signal on the CLK pin can deactivate the external load resistor.

[0048] In some embodiments of the invention, the D flip-flop threshold voltage value is 2V.

[0049] This is a preferred value ensuring a reliable functioning.

[0050] In some embodiments of the invention, the fourth predetermined value is lower or equal to the first predetermined value.

[0051] This is a preferred value ensuring also a safe and reliable functioning of the gate actuator.

[0052] It is a further aim of the present invention to provide an improved closure system having a support and a closure member which are connected to each other by at least one hinge, wherein the closure system further comprises a gate actuator according to any one of the preceding embodiments.

[0053] The advantages and effects of the embodiments described above are also achieved with a closure system having a support and a closure member that are connected to each other by at least one hinge, the closure system further comprising a gate activator as described in one of the embodiments above.

[0054] It will be readily appreciated that, as will also become evident from the further description, that the above mentioned embodiments of the present invention (incl. preferred, more preferred, advantageous, more advantageous, alternative, etc. embodiments and / or other optionally indicated features) should not be limited to individual elements, but may be combined with one another to achieve even other embodiments than those already described, which embodiments may also be part of the present invention as defined in the appended claims.

[0055] Brief description of the drawings

[0056] The invention will be further explained by means of the following description and the appended figures.

[0057] Figure 1 shows a perspective view of a closure system with a gate actuator and the closure member in an open position according to an embodiment of the invention.

[0058] Figure 2 shows a perspective view of a closure system with a gate actuator and the closure member in a closed position according to an embodiment of the invention.

[0059] Figure 3 shows a view of a mounted gate actuator illustrating the position of the electromotor.

[0060] Figure 4 shows a schematic view of an electrical circuit of the gate actuator illustrating the two parts.

[0061] Figure 5 shows a schematic view of a motor control circuit 100 for the DC electromotor according to an embodiment of the invention.

[0062] Figure 6 shows a brake resistor circuit in more detail according to an embodiment of the invention.

[0063] Figure 7 shows an external load resistor mounted in the housing of a gate actuator according to an embodiment of the invention.

[0064] Figure 8 shows a magnified view of a window in figure 7. Figure 9 shows a perspective view of the gate actuator with the housing opened to illustrate the printed circuit board.

[0065] Figure 10 shows a magnified view of a window in Figure 8 to illustrate the external load resistor and the connector on the printed circuit board for the external load resistor.

[0066] Figure 11 is a portion of the electric scheme of the gate actuator as shown in an electronic scheme software illustrating the controller and the connection pins on the controller connected to the brake resistor circuit.

[0067] Figure 12 shows an alternative brake resistor circuit in more detail according to an embodiment of the invention.

[0068] Description of the invention

[0069] The present invention will be described with respect to particular embodiments and with reference to certain drawings but the invention is not limited thereto but only by the claims. The drawings described are only schematic and are non-limiting. In the drawings, the size of some of the elements may be exaggerated and not drawn on scale for illustrative purposes. The dimensions and the relative dimensions do not necessarily correspond to actual reductions to practice of the invention.

[0070] Furthermore, the terms first, second, third and the like in the description and in the claims, are used for distinguishing between similar elements and not necessarily for describing a sequential or chronological order. The terms are interchangeable under appropriate circumstances and the embodiments of the invention can operate in other sequences than described or illustrated herein.

[0071] Moreover, the terms top, bottom, over, under and the like in the description and the claims are used for descriptive purposes. The terms so used are interchangeable under appropriate circumstances and the embodiments of the invention described herein can operate in other orientations than described or illustrated herein.

[0072] Furthermore, the various embodiments, although referred to as “preferred” are to be construed as exemplary manners in which the invention may be implemented rather than as limiting the scope of the invention.

[0073] The term "substantially" includes variations of + / - 10% or less, preferably + / -5% or less, more preferably + / -1 % or less, and more preferably + / -0.1 % or less, of the specified condition, in as far as the variations are applicable to function in the disclosed invention. It is to be understood that the term "substantially A" is intended to also include "A".

[0074] The invention generally relates to an electrically driven gate actuator 3 for closing and opening a closure system as illustrated in Figure 1. The closure system comprises a support 1 , such as a wall or a post, and a moveable closure member 2, such as a gate, a door, or a window. The closure member 2 is connected to the support 1 by means of hinges 4. These hinges can be any kind of hinges known in the art. A second support 5 may be provided on the other side of the closure member 3 and may be provided with a lock and keeper assembly, e.g., using a lock as disclosed in E P 1118559 or EP 2915939 the content of which are incorporated herein by reference and a keeper disclosed in EP 1600584 or EP 1680567 the content of which is incorporated herein are reference.

[0075] The gate actuator 3, as illustrated for example also on Figure 2, comprises an elongated housing 9 extending in a longitudinal direction between a first end 9a and a second end 9b. The elongated housing 9 is preferably manufactured from extruded aluminium, but other materials could also be used. The elongated housing 9 is connected to the support 1 by means of any kind of fixture means. Alternatively, the gate actuator could also be partly or completely mounted inside a hollow support.

[0076] On top of the housing 9, a driver 7 (e.g., a rotating arm) is provided which extends from the housing towards the closure member 2. On the free end of the driver 7, the driver 7 is connected to the closure member 2. In the illustrated embodiment, the driver 7 is manufactured from aluminium. In alternative embodiments, alternative materials known in the art can be used for the driver 7.

[0077] The gate actuator 3 includes an electromotor 8 which is illustrated on Figure 3. The electromotor is a DC electromotor disposed in the housing 9. An advantage of using an electric motor is the compactness. The electromotor comprises a motor body with the means required for rotating an output shaft (not shown). This output shaft extends towards to the top 9a of the housing 9. An example of such an interior construction is shown in figure 7 of WO 2019 / 048359 which is incorporated herein by reference. The output shaft is rotatable in both rotational directions upon activation of the electromotor 8 to open and close the gate member 2. The electromotor 8 is further provided with control means which allow calibrating the resting position of the driver 8 once the gate actuator 3 is mounted on the closure system. The gate actuator 3 further has a printed circuit board which is mounted in the housing 9. The printed circuit board 90 is illustrated on Figure 9 and Figure 10 whereby Figure 10 is a magnified view of a window on Figure 9. Figure 10 shows the connector 340 on the printed circuit board 90 to connect the external load resistor 70.

[0078] Figure 4 is a schematic view of an electrical circuit 30 of the gate actuator 3. The electrical circuit 30 is divided in two parts. A first part circuit 31 is electrically connected with a second part circuit 32 by a diode 50. The diode 50 is positioned such that current can run from the first part circuit to the second part circuit.

[0079] Figure 5 illustrates a schematic view of a motor control circuit 100 for the DC electromotor 8 of the gate actuator 3 according to an embodiment of the invention. The brushless DC motor 8 is designed with three wires. The three wires are in connection with six MOSFETS 105 (Metal Oxide Semiconductor Field-Effect Transistor) which are controlling the voltage on the three wires. This configuration of a three-wire brushless DC motor controlled by 6 MOSFETS is known in the art. The motor control circuit is positioned in the second part circuit 32 divided from the first part circuit by the diode 50.

[0080] The main input towards the motor controller 95 is at 24V as illustrated in Figure 5. The MOSFETS 105 are in normal operation conducting a current from the main input towards the wires of the brushless DC motor 8. However, when the brushless DC motor 8 is generating current instead of consuming, the MOSFETS 8 are allowing that this current is conducted in the reverse direction, i.e. from the brushless DC motor 8 to the other components in the electrical circuit. To avoid damage in the larger electrical circuit, the motor control part 32 of the electrical circuit 30 is separated from other parts of the electrical circuit of the gate actuator 3 and a diode 50 is provided before the 24V main input of the motor control circuit. For this reason, the electrical circuit 30 of the gate actuator is divided in two parts as illustrated in Figure 4 whereby the motor control circuit 100 is located in the second part circuit 32. By providing the diode 50 at this position, no current can run from the motor control circuit part towards the other parts of the electrical circuit of the gate actuator. A situation wherein current is generated by the brushless DC motor is when someone is pushing on the gate.

[0081] To control the energy in the situation that the brushless DC motor 8 is generating energy, a brake resistor circuit 200 is integrated in the electrical circuit 30. The brake resistor circuit 200 is also integrated in the second part circuit 32 as illustrated in Figure 4. The brake resistor circuit is further illustrated in more detail in Figure 6. The brake resistor circuit 200 is connected to a conductive path at the motor side of the diode 50. This conductive path is at a motor side voltage 215 as illustrated on Figure 4. When the motor is operating in a normal mode, the motor side voltage 215 is the same as the supply voltage 210 of the system at the other end of the diode 50 as shown on Figure 4. In the embodiment of Figure 6, this voltage is 24V.

[0082] The voltage at the motor side of the circuit in the conductive path in direct electrical connection with the diode 50 is also on Figure 6 indicated with reference number 215. The motor side voltage 215 is 24V when the brushless DC motor is acting in normal operation, i.e. the motor is controlled at 24V. The motor side voltage 215 may however change if the brushless DC motor 8 is generating energy, i.e. in the situation when a user is pushing on the closure member 2, for example a gate, during opening or closing, even when the DC electromotor 8 is not activated. In that situation the electromotor is acting as a generator.

[0083] The brake resistor circuit 200 as illustrated in the embodiment of Figure 6 has a PNP transistor 202 which conducts from Emitter pin 203 to Collector pin 204 when current can flow from Emitter pin 203 to Base pin 205. The current flowing from Emitter pin 203 to Collector pin 204 is approximately 100 times more than the current flowing from Emitter pin 203 to Base pin 205. The typical Base-Emitter voltage of a PNP transistor is 0.7V and since Base pin 205 is connected to 24V, current will flow from Emitter to Base when the motor side voltage 215 rises above 24.7V. This Base-Emitter current creates an Emitter-Collector current which is approximately 100 times bigger. The sum of these two currents will bring the system in equilibrium where the voltage at Emitter pin 203 remains at 24.7V regardless of the voltage at the motor side voltage 215.

[0084] The total current that flows is defined by resistors 208 and 209 and can be calculated as (motor side voltage 215 - 24.7V) 1 200K, i.e. I=V / R. Because of the function of a PNP transistor, approximately 99% of this current flows through Collector pin 204 and third and fourth resistors 211 and 212. The remaining 1 % flows out of the Base pin 205 into the 24V supply.

[0085] The current through the fourth resistor 212, a resistor of 22K Ohm, creates a voltage in the conductive path before the fourth resistor 212 equal to: current I x 22K, i.e. V=I*R. This means that the resistance value of the fourth resistor 212 determines the voltage in the conductive path before the fourth resistor 212. A capacity 214 is positioned between the conductive path before resistor 212 and ground 220. The purpose of capacity 214 is to filter out minor disturbances.

[0086] The brake resistor circuit 200 further comprises a comparator 230. The comparator 230 compares the voltage at pin 231 , i.e. the IN- pin, with the voltage at pin 233, i.e. the IN+ pin. Pin 233, i.e. the IN+ pin, is connected by a fifth resistor 237 with a stable external voltage reference 238. In the embodiment of Figure 6, the external voltage reference 238 is 2,5V. The IN- pin 231 is connected in the circuit 200 with the conductive path before the fourth resistor 212. When the voltage at the IN- pin 231 is lower than the voltage at the IN+ pin 233, Output pin 234 is not connected to Ground and floating. And, when the voltage at the IN- pin 231 is higher than the voltage at the IN+ pin 233, the Output pin 234 is connected to Ground.

[0087] A stable power supply is provided to the comparator at the comparator VCC pin 235. This is realized by connecting the comparator VCC pin 235 to a sixth resistor 240 and to a second capacity 239. The sixth resistor 240 is at its other end connected to a DC power source 241 and the second capacity 239 is at its other end connected to Ground 220. In the embodiment of Figure 6, the DC power source is a 12V power supply, the sixth resistor 240 is 33 Ohm and the capacity is 100nF.

[0088] The Output pin 234 of the comparator is connected to a conductive path with two resistors, a seventh resistor 243 and an eight resistor 244. By these resistors, the voltage at output pin 234 is in the subsequent conductive path 245 adapted to 3,3V when the voltage at pin 231 is lower than the voltage at pin 233, and the voltage in the subsequent conductive path 245 remains 0V when the voltage at pin 231 is higher than the voltage at pin 233.

[0089] The brake circuit 200 according to the embodiment of Figure 6 is further comprising a Schmitt trigger 250. The Schmitt trigger 250 makes the comparator’s output digital. The Schmitt trigger 250 realises this by using a different threshold for low to high transitions than for high to low transitions. In case of small fluctuations or noise, the Schmitt trigger 250 is configured such that the output of the Schmitt trigger 250 remains stable.

[0090] A subsequent component in the brake resistor circuit 200 according to the embodiment of Figure 6, is a D flip-flop 270. The D flip-flop 270 is a memory element that can store one bit of data. In alternative embodiments another type of a one-bit memory element may be used such as for example another type of flip-flop, a latch or any other one-bit element. In the embodiment of Figure 6, the D flip-flop 270 copies data on a D pin 273 to a Q pin 274 when a clock pulse is seen on CLK pin 271 . A CLR pin 276 is provided for clearing the memory and for setting the Q pin 274 low regardless of what happens on the other pins. The CLR pin 276 is in the brake resistor circuit electrically connected with the conductive path in direct electrical connection with the output pin 254 of the Schmitt trigger 250.

[0091] A third capacity 280 and a fourth capacity 281 are provided to provide stability to a one-bit memory element power supply 285. The one- bit memory element power supply 285 is in the embodiment of Figure 6 3,3 V.

[0092] The conductive path connected with at the memory element Q pin 274 of the D flip-flop 270 further comprises a ninth resistor 283. The other end of the ninth resistor 283 is connected to a NPN Base pin 291 of a NPN transistor 290 and to a tenth resistor 284 which is on its other pin connected to ground 220. A NPN Emitter pin 292 of NPN transistor 290 is also connected to ground. The combination of the ninth resistor 283, the tenth resistor 284 and the NPN transistor 290 form a classic NPN circuit. When voltage is applied to ninth resistor 283, current runs through the NPN Base pin 291 of the NPN transistor 290 and an NPN Collector pin 293 conduct via the NPN Emitter pin 292 to ground 220.

[0093] The brake resistor circuit 200 of Figure 6 further comprises a Zener diode 310 which is at the anode pin 312 electrically connected to ground and at the cathode pin 311 electrically connected to the NPN Collector pin 293 of NPN transistor 290, to an eleventh resistor 294 and to a twelfth resistor 296. The eleventh resistor 294 is at its other end connected to a thirteenth resistor 295 which is at its other pin connected to the motor side voltage 215. The eleventh resistor 294, the thirteenth resistor 295 and the Zener diode 310 together stabilize the motor side voltage at the level of Zener voltage when the motor side voltage 215 is higher than the Zener voltage. This is realized by the Zener diode 310 which, when current flows through it, stabilizes the voltage at the Zener voltage. In the embodiment of Figure 6, the Zener diode 310 has a Zener voltage of 12V.

[0094] As a result, at location 315 in the brake resistor circuit 200, the voltage is stabilized at 12V, unless the NPN transistor 290 is activated in which case the voltage at location 315 is approximately 0V. The activation of the NPN transistor 290 is regulated by the current flowing into the Base of the NPN transistor 290 at the NPN Base pin 291. The base-emitter voltage of an NPN transistor is 0.7V. When the voltage at NPN Base pin 291 is higher than 0.7V, current will flow into the base of the NPN transistor 290 and will allow an amplified current from the Collector of transistor 290 at the NPN Collector pin 293 to the Emitter of the NPN transistor 290 at the NPN Emitter pin 292. The amplification factor is in the embodiment of Figure 6 approximately 300.

[0095] When output 274 of the D-flip-flop 270 is 3.3V, a current will flow through the resistor 283 of (3.3V - 0.7V) / 10K = 0.26mA. This current is split between resistor 284 and the base of transistor 290 at pin 291. Resistor 284 will take about (0.7V I 47K) = 0.01 mA and the remaining 0.25mA will flow into pin 291 of the transistor 290.

[0096] The current of 0.25mA in pin 291 will allow for an approximate current from pin 293 to 292 of (0.25mA * 300) = 75mA. This current is limited by the 2 resistors 295 and 294 to (motor voltage 215 / 200k) so the current through pin 293 can never reach 75mA. As a result, the voltage at pin 293 will be approximately 0V. This is commonly known as a transistor in saturation.

[0097] The resistor 296, connected at one end to the Zener diode 310, the transistor 290 and the resistor 294, is at its other end connected to a resistor 317, a diode 320 and a transistor 300. The resistor 296, the resistor 317, the diode 320 and the transistor 300 form together an emitter follower. This group of components together ensure together that the voltage at location 325 in the brake resistor circuit 200 has the same value as the voltage at location 315 without the need for current to flow through resistors 294 and 295. This design of the brake resistor circuit 200 is arranged to quickly turn on a Mosfet 330 which serves as a switch to control a load resistor 70 via a connector 340 which is connected to the Mosfet 330 at pin 332 and to the power side voltage 215. The external load resistor is illustrated on Figure 7 and Figure 8, wherein Figure 8 is a magnified view of the circular window indicated on Figure 7. Two wires 71 , 72, each on one side of the load resistor 70 are connecting to a second connector 75. The second connector 75 is arranged to connect with the connector 340. The external load resistor 70, connected via the second connector 75 to the connector340 is by this configuration at the first connection 341 connected to the motor side voltage 215 and at the second connection 342 connected to the Drain pin 332 of the mosfet 330. As a result, the Mosfet 330 can control the external load resister 70. When the mosfet 330 conducts, the external load resistor 70 is activated and consuming energy. When the mosfet 330 is not conducting, the external load resistor 70 is deactivated.

[0098] Operation of brake resistor circuit 200

[0099] When the motor side voltage 215 is at a first predetermined value, in the embodiment of Figure 6 more than 23.4V higher than the system voltage 210, which is in the embodiment of Figure 6 24V, current flows through the fourth resistor 212 creating a voltage at the IN- pin 231 of the comparator 230 higher than 2,5V.

[0100] Because pin 231 , IN- of the comparator 230, is at that moment higher than pin 233, IN+ of the comparator 230, the operation of the comparator switches and the output at pin 234 becomes 0V. The Schmitt trigger 250 stabilizes this voltage without altering the signal. By that, pin 276, the CLR line of the D flip-flop 270, is set at 0V. This causes that the output of the D flip-flop at pin 274 is also at 0V.

[0101] Because pin 274 of the D flip-flop 274 is over the resistor 283 connected to transistor 290, pin 291 of the transistor is also at 0V. This turns off the transistor 290 causing that the location 315 of the brake resistor circuit 200 is at 12V.

[0102] Because the location 315 of the circuit 200 is over the resistor 296 connected to the transistor 300, pin 303 of the transistor 300 receives also this voltage and the transistor 300 conducts via pin 301 to pin 331 of the mosfet 330, i.e. the gate of the mosfet. This voltage at the gate of the mosfet 330 causes the mosfet 330 to conduct. When the mosfet conducts, current runs through the connector 340 and thus also through the external load resistor 70 which is connected to the connector 340. By this, current is drawn from the system and the motor side voltage 215 is lowered.

[0103] The electrical circuit board further comprises a controller 95. The controller 95 is shown on Figure 11. The controller 95 receives via conductive path MC_D_STAT 350 a signal from the brake resistor circuit 200. The box MC_D_STAT on Figure 6 is illustrating where conductive path 350 is connected with conductive path 350 in Figure 11 illustrating the connection to a pin 97 of the controller 95. In the brake resistor circuit 200 the conductive path MC_D_STAT is electrically connected to the conductive path in direct electrical connection with the Q pin 274 of the D flip-flop 270. The controller 95 is configured to determine from the signal 350 if the external load resistor 340 is activated.

[0104] The controller also measures the motor side voltage 215 and is configured to disable the external load resistor 340 when the motor side voltage 215 drops enough taking into account the supply voltage 210. The controller 95 generates via conductive path MC_D_RST 360 a clock pulse. The controller 95 is via a second pin 98 and the conductive path MC_D_RST 360 connected to the CLK pin 271 of the D flip-flop 270. By generating a clock pulse at pin 271 of the D flip-flop, i.e. at the CLK pin of the D flip-flop, the D flip-flop copies the data at the pin 273 (D contact) of the D flip-flop, which is connected to power supply 285 which is in the embodiment of Figure 6 3,3V, to the pin 274 (Q contact) of the D flip-flop. The D flip-flop only copies data from the D contact to the Q contact when the CLR pin 276 is above the D flip-flop threshold voltage value which is in the embodiment of Figure 62V. When the motor side voltage 215 is higher than the first predetermined value on which the external load resistor is activated, the voltage at the output pin 254 of the Schmitt trigger is 0V. The voltage at the CLR pin 276 is therefore also at 0V when the external load resistor is activated. As a result, the controller 95 cannot deactivate the external load resistor 340 until the motor side voltage 215 is below the first predetermined value. This first predetermined value on which the external load is activated is in the embodiment of Figure 6 47.4V when the system supply voltage 210 is 24.0V. By having this specific structure, the controller 95 can never deactivate the external load resistor when the power side voltage 215 is still higher than the first predetermined value, also called threshold, of the power side voltage 215.

[0105] When the external resistor is to be deactivated, the Q contact of the D flip-flop becomes high at pin 274. According to the datasheet this voltage is at least 2.4V. When the pin 274 is high, this turns on transistor 290. As a result, the voltage at location 315 in the circuit is 0V.

[0106] The transistor 300 conducts this voltage towards location 325 in the circuit. With 0V at pin 331 of the mosfet 330, the mosfet 330 turns off and the external load resistor 340 is disconnected.

[0107] The system is further configured such that, in the event the motor is activated when the entire system is not powered, the external load resistor 340 is always activated. This avoids that in a situation that the gate actuator is not powered, the electronics would be damaged if someone is operating the gate manually and as a result generates energy into the electronics of the gate actuator. In the embodiment of Figure 6, this is arranged by having a system wherein the D flip-flop is configured such that when the D flip-flop 270 is not powered, its output is at 0V. The following configuration of the circuit keeps subsequently the voltage at position 315 from being pulled to ground. Point 315 follows the motor side voltage 215 until it reaches 12V at which point the Zener diode 310 starts to conduct.

[0108] This voltage at location 315 in the circuit is also at the pin 303 of the transistor 300 and via the transistor 300 also at pin 331 of the mosfet 330. The mosfet 330 conducts as soon as a predefined threshold is reached. In a preferable embodiment is this threshold of mosfet 330 3.2V.

[0109] An alternative embodiment of the brake resistor circuit is illustrated in Figure 12. The brake resistor circuit 400 of Figure 12 contains, compared to the brake resistor circuit 200 of Figure 6, an additional buffer 401 and an additional resistor 402. The buffer 401 is controlled by the conductive path MC_D_RST connected to the controller 95 and the CLK-pin 271 of the D flip-flop 270. For that the in-pin 404 is connected to this conductive path and the out-pin 406 is connected to the additional resistor 402. When the conductive path at the in-pin 404 is at high voltage, the additional resistor 402 is in parallel with the fifth resistor 237 and the voltage on the comparator reference pin IN + 233 is at the voltage of the DC power source 238 which is the same as in the first embodiment of the brake resistor circuit 200. To realize this, the VCC-pin 407 is connected to DC power source 238. In the embodiment of Figure 12, the DC power source 238 is 2,5V. But, when the conductive path MC_D_RST is at low voltage, the additional resistor 402 is connected to Ground and the voltage on the comparator reference pin IN+ 233 will drop. In the embodiment of Figure 12, the voltage at pin IN+ 233 drops to 0,45V. This causes the brake resistor circuit 402 to trigger at a lower value of the motor side voltage 215. In the embodiment of Figure 12 the value lowers to 28,5V on the motor side voltage 215. To compare, in the embodiment of Figure 6, this value is 47,4V.

[0110] Although aspects of the present invention have been described with respect to specific embodiments, it will be readily appreciated that these aspects may be implemented in other forms within the scope of the present invention as defined by the appended claims.

Claims

CLAIMS1 . A gate actuator (3) for closing and opening a closure system having a support (1 ) and a closure member (2) that are hingedly connected to each other, the gate actuator comprising:- an elongated housing (9) configured to be mounted to the support, the elongated housing extending in a longitudinal direction between a first end (9a) and a second end (9b);- a DC electromotor 8 mounted in the housing, the electromotor having an output shaft near the first end of the elongated housing and which is rotatable around said longitudinal direction upon activation of the electromotor or upon rotation of the closure member;- a driver (7) operatively connected to the output shaft, the driver being configured to rotate the closure member (2) upon rotation of the output shaft and to rotate the shaft upon rotation of the closure member; and- a printed circuit board (90) mounted in the housing and comprising an electrical circuit (30), wherein the electrical circuit is electrically connected to the DC electromotor to control the DC electromotor, characterized in that- the electrical circuit comprises a first part circuit (31 ) and a second part circuit (32) wherein the first part circuit is electrically connected to the second part circuit via a diode 50, wherein the diode is conducting from the first part circuit to the second part circuit providing a motor side voltage (215) in the second part circuit at a location subsequent the diode, in that- the second part circuit comprises a motor control circuit (100) electrically connected to a conductive path subsequent the diode at the motor side voltage (215) to control the DC electromotor, wherein the motor control circuit (100) comprises at least one mosfet, and a brake resistor circuit (200) electrically connected to a conductive path subsequent the diode at the motor side voltage (215), and in that- the gate actuator further comprises an external load resistor electrically connected to the brake resistor circuit (200) of the printed circuit board (90),wherein a first connection of the external load resistor is connected to a conductive path subsequent the diode at the motor side voltage (215) and wherein the brake resistor circuit (200) is configured to activate the external load resistor when the motor side voltage (215) reaches a first predetermined voltage.

2. The gate actuator according to claim 1 , wherein the brake resistor circuit (200) is configured to activate the external load resistor when the gate actuator is not powered and the motor side voltage reaches a second predetermined voltage.

3. The gate actuator according to claim 2, wherein the brake resistor circuit (200) further comprises a one-bit memory element (270) comprising an output pin (274) wherein the One-bit memory element (270) is configured to provide at the output pin 0V when no voltage is received at other pins of the One-bit memory element, wherein the brake resistor circuit further comprises a Zener diode (310) having a cathode pin (311 ) and an anode pin (312) and which is electrically connected at the cathode pin to the motor side voltage (215) and the output pin (274) of the one-bit memory element, wherein the Zener diode is configured to stabilize the motor side voltage (215) to a third predetermined voltage at a conductive path in the circuit in direct electrical contact with the cathode pin of the Zener diode when the motor side voltage is at least equal to the third predetermined voltage, wherein the brake resistor circuit further comprises a mosfet (330) electrically connected to the Zener diode (270), wherein the mosfet is at its other pins electrically connected to the motor side voltage (215) and to ground, wherein conductive path between the motor side voltage and the mosfet is configured to conduct current through the external load resistor, and the mosfet is configured to conduct when the second predetermined voltage at the Zener diode is reached causing that the external load resisterto consume energy when the gate actuator is not powered and the motor side voltage reaches the second predetermined voltage.

4. The gate actuator according to any of the preceding claims, wherein the brake resistor circuit (200) further comprises a PNP transistor, which has a Base pin (205) at 24V, an Emitter pin (203) electrically connected to the motor side voltage (215) and a Collector pin (204) electrically connected to Ground, wherein the brake resistor circuit further comprises a fourth resistor (212) which creates a first voltage in the conductive path before the resistor (212) when the PNP transistor is conducting, and wherein the resistance value of the fourth resistor (212) determines the first predetermined value.

5. The gate actuator according to claim 4, wherein the fourth resistor (212) is 22 KOhm and wherein the first predetermined value is 47,4 V.

6. The gate actuator according to any of the preceding claims, wherein the brake resistor circuit (200) further comprises a comparator (230), which has a IN+ pin (233) electrically connected to a reference voltage supply (238), wherein the voltage value of the reference voltage supply determines the first predetermined value.

7. The gate actuator according to claim 6, wherein the reference voltage supply (238) is 2,5V and wherein the first predetermined value is 47,4 V.

8. The gate actuator according to any of the claims 6 to 7, wherein the brake resistor circuit (200) further comprises a Schmitt trigger (250) electrically connected to an Output pin (234) of the comparator (230).

9. The gate actuator according to any of the preceding claims, wherein the brake resistor circuit (200) further comprises a one-bit memory element (270).

10. The gate actuator according to any of the preceding claims, wherein the brake resistor circuit (200) further comprises a one-bit memory element (270) which has a memory element Q pin (274) as output, a CLK pin (271 ) for receiving a clock signal from a controller (95) and a memory element D pin as input, wherein the one-bit memory element (270) copies data from the memory element D pin (273) to the memory element Q pin (274) when a clock pulse is seen at the CLK pin (271 ).11 . The gate actuator according to any of claims 9-10, wherein the one-bit memory element is a D flip-flop.

12. The gate actuator according to any of the preceding claims, wherein the brake resistor circuit (200) further comprises a NPN transistor (290), which has a NPN Base pin (291 ), a NPN Emitter pin (292) electrically connected to ground (220) and a NPN Collector pin (293) electrically connected to a conductive path in the circuit, wherein the brake resistor circuit is configured to control the voltage in the conductive path in the circuit in direct electrical connection with the NPN Collector pin by controlling the voltage at the NPN Base pin of the NPN transistor.

13. The gate actuator according to claim 12, wherein the brake resistor circuit (200) further comprises a Zener diode having a cathode pin (311 ) and an anode pin (312) and which is electrically connected at the cathode pin to the motor side voltage (215) and the NPN Collector pin (293) of the NPN transistor (290), wherein the Zener diode is configured to stabilize the motor side voltage (215) to a Zener voltage at a conductive path in thecircuit in direct electrical contact with the cathode pin of the Zener diode when the NPN transistor 290 is not activated.

14. The gate actuator according to any of the preceding claims, wherein the brake resistor circuit (200) further comprises a mosfet (330) which has a gate pin (331 ), a source pin (333) and a drain pin (332), wherein the drain pin (332) is electrically connected to a second connection (342) of the external load resistor (70), wherein the source pin (333) is electrically connected to ground (220), and wherein the brake resistor circuit (200) is configured to provide a voltage at the gate pin of the mosfet which is higher than a threshold voltage value of the mosfet when the motor side voltage (215) reaches the first predetermined voltage.

15. The gate actuator according to claim 14 when dependent on claim 13, wherein the gate pin (331 ) of the mosfet is electrically connected to the conductive path in the circuit in direct electrical contact with the cathode pin (293) of the Zener diode, and wherein the brake resistor circuit is configured that the voltage at the gate pin (331 ) of the mosfet is the same as the voltage at the conductive path in the circuit in direct electrical contact with the cathode pin of the Zener diode.

16. The gate actuator according to any one of the preceding claims, wherein the printed circuit board (90) further comprises a controller (95), wherein the controller is electrically connected to the brake resistor circuit to receive a signal, and wherein the controller is configured to determine if the external load resistor (70) is activated based on the signal.

17. The gate actuator according to claim 16, wherein the controller (95) is configured to measure the motor side voltage (215), and wherein the controller is configured to deactivate the external load resistor when the motor side voltage is lowered below a fourth predetermined value.

18. The gate actuator according to any one of the preceding claims, wherein the brake resistor circuit is configured to deactivate the external load resistor by switching the D flip-flop (270).

19. The gate actuator according to any one of the preceding claims, wherein the printed circuit board (90) further comprises a controller (95), wherein the controller is configured to control a clock signal to the CLK pin, and wherein the braker resistor circuit is configured such that the controller cannot deactivate the external load resistor when the motor side voltage (215) is higher than the first predetermined value.

20. The gate actuator according to claim 19, wherein the voltage at the CLR pin 276 of the D flip-flop is lower than the D flip-flop threshold voltage value of the D flip-flop when the motor side voltage (215) is higher than the first predetermined value.

21. The gate actuator according to claim 19, wherein the D flip-flop threshold voltage value is 2V.

22. The gate actuator according to claim 17, wherein the fourth predetermined value is lower or equal to the first predetermined value.

23. A closure system having a support (1 ) and a closure member (2) which are connected to each other by at least one hinge (4), characterized in that the closure system further comprises a gate actuator (3) according to any one of the preceding claims.

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