An electric gate actuator and a closure system comprising the same

Abstract

An electric gate actuator for actuating a closure system having a first member and a second member that are moveable with respect to each other. The gate actuator comprises: a frame; an electromotor (5) mounted on the frame and comprising: a rotor, a stator and a brake mechanism which comprises: a first friction disc (39) rotatably fixed to the rotor, a second friction disc (40) rotatably fixed to the stator, and a biasing member urging the friction discs against one another; and a mechanical uncoupling system which engages one of the friction discs to move the frictions discs away from one another against the force of the biasing member.

Description

Technical field

[0001] The present invention generally relates to an electric gate actuator electric gate actuator for actuating a closure system having a first member, in particular a gate post, and a second member, in particular a gate. The closure members may be hingedly connected to each other or may be slidable with respect to one another. The present invention further relates to a closure system comprising such an electric gate actuator.Background art

[0002] Various types of gate actuators are known in the art, for example spring-biased gate actuators as disclosed in WO 2012 / 103572 which serve to automatically close the gate; hydraulically damped spring-biased gate actuators as disclosed in WO 2018 / 228729 which also serve to automatically close the gate; and electric gate actuators as disclosed in WO 2019 / 048359 which serve to both open or close the gate. The present invention is generally related to gate actuators of the latter kind which are operated by an electromotor. Such gate actuators are also commonly referred to as gate openers and may be used both in the context of hinged closure systems or slidable closure systems.

[0003] A known electric gate comprises: a frame configured to be mounted to a first member of the closure system (e.g. a gate post); an electromotor mounted on the frame, the electromotor comprising: a rotor, a stator and a brake mechanism which comprises: a first friction disc rotatably fixed to the rotor, a second friction disc rotatably fixed to the stator, and a biasing member urging the friction discs against one another to prevent rotation of the rotor when insufficient power is supplied to the electromotor; a driver mounted on the frame and configured to transfer a rotation (e.g. directly transferring the rotation in case of a hinged closure system or involving a rack-and-pinion mechanism in case of slidable closure system) of the rotor to the second member (e.g. a gate); and a mechanical uncoupling system mounted on the frame for uncoupling the electromotor.

[0004] The brake mechanism is used to prevent unwanted or accidental opening or closing of the gate when no or insufficient power is supplied. More specifically, when the gate is closed, various forces may be exerted thereon (e.g. wind load, a person pushing on the gate, etc.). The brake mechanism ensures that such forces do not readily open the gate. To this end, two friction discs are urged together by the biasing member thereby creating a friction force between them. This friction prevents the rotation of the rotor even when a force is exerted on the gate.

[0005] The main advantage of such a brake system is that it is passive in the sense that it requires no power to operate. However, a known issue with such a brake is that the gate remains closed when there is a power failure. To this end, a manually operable mechanical unlocking system is present which allows uncoupling the electromotor from the closure system and particularly allows to disengage one or more components located between the electromotor and the driver.Disclosure of the invention

[0006] It is an aim of the present invention to provide an improved mechanical uncoupling system.

[0007] To this aim the gate actuator according to the present invention is characterized in that the mechanical uncoupling system engages one of the friction discs to move the frictions discs away from one another against the force of the biasing member.

[0008] A main advantage of the mechanical uncoupling system according to the present invention is its simplicity and reliability. By acting directly on the brake mechanism, the system enables disabling the brake thus allowing free rotation of the closure system even in the absence of power. However, contrary to the known uncoupling systems, there is no need to actually uncouple one or more components located between the electromotor and the driver, which components are crucial for the normal operation of the gate actuator. There is thus no risk that using the mechanical uncoupling system damages or wrongly re-engaging the mechanical uncoupling system could interfere with the normal working of the gate actuator.

[0009] An embodiment of the gate actuator is characterized in that the mechanical uncoupling system comprises a rod which is mounted on the frame, the rod having: a free end which engages (either directly or indirectly by one or more intermediary elements) said one of the friction discs; and a thread which engages a corresponding thread formed on the frame such that a rotation of the rod causes a sliding motion of the free end of the rod.

[0010] In this embodiment, the mechanical uncoupling system comprises relies on a rod that is slidably mounted on the frame between a rest state and an actuated state. In the rest state, the rod is not engaging the friction disc, whereas in the actuated state, the rod has slid the friction disc to disengage both friction discs. The threads further prevent that the rod would be slid to its rest state due to the force exerted by the biasing member. In other words, a user can release the rod once it has been slid to its actuated state.

[0011] An embodiment of the gate actuator is characterized in that the mechanical uncoupling system further comprises a worm drive having: a manually operable worm; and a worm wheel which engages said worm, the rod being irrotatably coupled to the worm wheel.

[0012] In this embodiment, the mechanical uncoupling system further comprises a worm drive to which the rod is coupled in a non-rotatable fashion. In other words, the rotation of the worm wheel causes a same rotation of the rod and vice versa.

[0013] The worm drive changes the rotational direction of motion. As such, whereas the rod is typically oriented vertically (in line with the gate post or gate) and thus rotates about the vertical axis, the worm drive enables operating the mechanical uncoupling system by means of rotating the worm about a different axis, e.g. a horizontal axis. This makes it easier to access the mechanical uncoupling system, especially considering that the end of the rod opposite the free end may not be accessible in case the gate actuator is mounted inside the gate or gate post. The worm drive thus allows to use a dedicated tool that can grip or engage with the worm in a horizontal plane as opposed to a wrench to grip the vertical rod and which would require sufficient space in the horizontal plane to rotate the wrench.

[0014] An embodiment of the gate actuator is characterized in that the electromotor comprises a base plate which is slidable with respect to the frame, said one of the friction discs being fixed to the base plate, wherein the free end of the rod contacts the base plate and wherein a rotation of the rod causes the base plate to slide with respect to the frame, wherein, preferably, the first friction disc is interposed between the base plate and the second friction disc which is fixed to the base plate.

[0015] The use of a base plate as an intermediary between the rod and the friction disc provides design freedom and flexibility. More specifically, the friction disc can be designed and the material can be chosen without having to take into account a contact with the rod and the local pressure that rod contact would create. Rather, the base plate is contact by the rod and handles the locally high pressure. Placing the first friction disc between the base plate and the second friction disc in essence results in a cage which surrounds the first friction disc, which cage is then slidable by being engaged by the rod.

[0016] An embodiment of the gate actuator is characterized in that the electromotor comprises an electromagnet and one of the friction discs comprises a magnetic element which is configured to be attracted to the electromagnet when sufficient power is supplied to the electromotor to overcome the biasing member thereby moving the friction discs away from one another.

[0017] The electromagnet forms part of the normal operation of the gate actuator. More specifically, when power is supplied, the electromagnet attracts one of the friction discs thus disengaging the brake mechanism against the force of the biasing member.

[0018] As used herein, the term "magnetic element" is intended to refer to an element or part thereof which is attracted by an electromagnet, such as manufactured (in part) of a (soft) ferromagnetic or ferrimagnetic material.

[0019] An embodiment of the gate actuator is characterized in that the second friction disc comprises a first disc layer facing the first friction disk and a second layer comprising said magnetic element, the first layer preferably being formed from stainless steel or a ceramic material and the second layer preferably being formed from a ferromagnetic material.

[0020] A two layer friction disc allows to optimize the material choice with one layer being designed to be sufficiently magnetically attracted to the electromagnet, whilst the other layer can be designed to provide the desired amount of friction and / or to withstand potential wear and tear as part of the friction brake.

[0021] An embodiment of the gate actuator is characterized in that the electromotor has an output shaft protruding from a side of the electromotor and the brake mechanism and the mechanical uncoupling system are positioned on the opposite side of the output shaft.

[0022] Placing the brake mechanism on the other side of the electromotor than the output shaft reduces the risk of these components interfering with one another.

[0023] An embodiment of the gate actuator is characterized in that the electric gate actuator further comprises a gearing mounted on the frame and interposed between the rotor of the electromotor and the driver, wherein the mechanical uncoupling system and the gearing are preferably placed on opposite sides of the electromotor.

[0024] The use of a gearing (or gearbox) serves to reduce the speed and increase the torque of a compact electromotor so that the gate can be actuated with sufficient force. In an embodiment, the gearing has a reduction that is between 1:100 and 1:1000, for example 1:200 or 1:400. Placing the brake mechanism on the other side of the electromotor than the gearing reduces the risk of these components interfering with one another.

[0025] An embodiment of the gate actuator is characterized in that the electromotor is a brushless DC motor.

[0026] A brushless DC motor has multiple advantages over conventional brushed DC motors, such as a compact design, reduced wear and tear and a lower maintenance, high efficiency, etc.

[0027] An embodiment of the gate actuator is characterized in that the electric gate actuator further comprises a gearing mounted on the frame and interposed between the rotor of the electromotor and the driver, the gearing having a ratio between 1:400 and 1:1000, preferably between 1:500 and 1:800, the ratio more preferably being between 1:600 and 1:700.

[0028] It is advantages to avoid too high a gearing since, when the uncoupling mechanism is activated, a user still has to manually move the closure system. That is, the gate actuator has to be back-drivable. A too high gearing causes issues with the back-drivability as a too high force is required to move the closure system. A too low gearing on the other hand requires a more powerful electromotor which is thus less compact, more expensive, etc.

[0029] An embodiment of the gate actuator is characterized in that the first friction disc is not slidable with respect to the frame and the second friction disc is slidable with respect to the frame between an engaging position in which the friction discs engage one another and a disengaging position in which the friction discs do not engage one another.

[0030] The use of slidable friction discs and a biasing member is a simple and reliable system to form a brake mechanism which involves no complex force transfer and / or complex multi-directional motions.

[0031] An embodiment of the gate actuator is characterized in that a biasing force of the biasing member and the static coefficient of friction between the frictions discs are such that the brake mechanism prevents rotation of the rotor up to a torque of at least 0,5 N·m and preferably at least 1 N·m, acting on the rotor.

[0032] The static friction between the friction discs is given by F f = µF N where µ is the static coefficient of friction and F N is the normal force which is determined by the biasing force of the biasing member. As the brake mechanism acts directly on the electromotor, only a relatively low friction is required as there is commonly a gearing present between the electromotor and the driver.

[0033] The specific value of torque resistance is mainly determined in function of the gearing ratio and the potential load expected on the closure system. In case of a hinged closure system, the wind load is typically estimated in the order of magnitude of 1000 to 2000 N. The brake mechanism has to thus be able to keep the closure system locked for such loads. This may be achieved with a brake mechanism that prevents rotation of the rotor up to a torque of 2-3 N·m with a gearing ratio between 1:600 and 1:700.

[0034] The advantages of the embodiments described above are also achieved with a closure system comprising: a first member, in particular a gate post; a second member, in particular a gate, that are particularly hingedly connected to each other by at least one hinge; and an electric gate actuator as described above mounted in the first member with the driver engaging the second member or said at least one hinge.

[0035] It will be readily appreciated that the driver can be directly coupled to the gate (e.g. using a sliding rail as disclosed in figures 8 to 10C of WO 2018 / 228729) or can be coupled to the eyebolt hinge (e.g. as in WO 2019 / 048359 or as in figures 1A to 3B of WO 2018 / 228729). Generally speaking, the electric gate actuator can be surface mounted on the outside of a gate post (e.g. as in WO 2019 / 048359). However, in the context of the present invention, the electric gate actuator is preferably mounted inside the first member, e.g. inside the gate post. This improves the security of the closure system as the electric gate actuator cannot be easily accessed for persons with ill intent. Furthermore, the electric gate actuator is also better protected from atmospheric influences. The visual result of integrating the electric gate actuator is also desired by users.

[0036] An embodiment of the gate actuator is characterized in that the mechanical uncoupling system comprises height adjustment means allowing to vary the placement of (part of) the mechanical uncoupling system with respect to the first member.

[0037] This makes it easier to rely on standardly manufactured first members (e.g. gate posts) having an access opening at a fixed place while at the same time allowing to vary the gate actuator placement within the first member as needed. Especially in the context of outdoor gates, there is a need to be able to vary the gate actuator placement to account for height or horizontal distances between various elements of the closure system. As such, having part of the mechanical uncoupling system that is adjustable allows aligning it correctly with the access opening.

[0038] An embodiment of the gate actuator is characterized in that the mechanical uncoupling system comprising a base body which is slidably mounted on the frame, the base body having a threaded opening, and in that the height adjustment means comprise: guiding means which guide the base body; and a manually rotatable threaded rod engaging the threaded opening, wherein a rotation of the threaded rod causes a sliding motion of the base body.

[0039] The use of a base body allows to mount all needed components of the mechanical uncoupling system thereon and to have all these simultaneously slidable as desired. A threaded rod and threaded opening are well known means to transfer a rotational motion into a sliding motion.

[0040] An embodiment of the gate actuator is characterized in that the guiding means comprise a housing in which the base body is form-fitting.

[0041] The use of form-fitting elements avoids the need to provide additional rotation restriction elements.

[0042] An embodiment of the gate actuator is characterized in that the worm is mounted on the base body.

[0043] The worm is thus slidable together with the base body.

[0044] An embodiment of the gate actuator is characterized in that the first member comprises an access opening which allows access to the mechanical uncoupling system, in particular to the worm.

[0045] This improves user convenience.

[0046] 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 claimsBrief description of the drawings

[0047] The invention will be further explained by means of the following description and the appended figures. Figure 1 shows a perspective view of a closure system according to the present invention. Figure 2 shows a front view of a gate actuator according to the present invention. Figure 3 shows the brake and uncoupling mechanism present in the gate actuator according to the present invention. Figure 4 shows an exploded view of figure 3. Figure 5 shows a horizontal cross-section through the uncoupling mechanism present in the gate actuator according to the present invention. Figure 6 shows a partial vertical cross-section through the gate actuator according to the present invention in the activated state. Figures 7A and 7B show a same detail of the vertical cross-section through the brake mechanism in the coupled and uncoupled state. Figures 8A and 8B show a same partial vertical cross-section through the gate actuator according to the present invention with the uncoupling mechanism at different heights. Figures 9A and 9B show different views of an access opening in the gate post providing access to the uncoupling mechanism. Description of the invention

[0048] 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.

[0049] 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.

[0050] 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.

[0051] 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.

[0052] 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".

[0053] The invention generally relates to an electric gate actuator 10 for closing a closure system having a first member and a second member that are hingedly connected to each other as shown in figure 1. The first member is typically a fixed support 1, such as a wall or a gate post, while the second member 2 is typically a moveable closure wing 2, such as a gate or a door. The members 1, 2 are connected by one or more hinges 3. The electric gate actuator 10 is typically used in outdoor applications (e.g. as part of a fence). The electric gate actuator 10 is primarily designed to be inserted in a hollow tubular member which may be part of either closure member, although the electric gate actuator 10 may also be surface mounted. In the illustrated embodiments, the electric gate actuator 10 is fixed with respect to the gate post 1 and a driver 4 is present to couple the electric gate actuator 10 to the gate wing 2. However, a reversal is also possible.

[0054] Furthermore, although the actuator 10 is described in relation to a hinged closure system, it may be used in the context of a slidable closure system as well.

[0055] The electric gate actuator 10 is shown in figure 2. The illustrated actuator 10 generally comprises an electromotor 5, a gearing 6 and an output shaft 7. The electromotor 5, preferably a brushless DC motor, is advantageous because of its compactness, which allows it to be incorporated inside the gate post 1. In an embodiment, the gearing 6 has a ratio between 1:400 and 1:1000, e.g. 1:600 or 1:700, such that an output of the electromotor 5 is amplified to the output shaft 7. The driver 4 is coupled directly or indirectly to the output shaft 7.

[0056] The illustrated actuator 10 further comprises a brake mechanism 8 and an uncoupling mechanism 9 which are the main aspects of the present invention. These mechanisms are shown in detail in figure 3 and in exploded view in figure 4.

[0057] The actuator 10 generally comprises a frame that is fixed directly or indirectly to the closure system. This frame is generally static and is formed by different elements in the illustrated embodiment. The frame comprises a lower end closing plate 11 to which a housing 12 is bolted by means of bolts 13. The housing 12 is also a frame component and acts as a housing for the uncoupling mechanism 9. The housing 12 extends in a first direction 15 (indicated in figure 2) which, in use, will typically substantially coincide with the vertical direction. An elongated access slot 14 is provided in the housing 12, which slot 14 extends in the vertical direction 15. The lower closing plate 11 is provided with, besides the multiple bolt openings, also two rod receiving openings. More specifically, a first rod receiving opening 16 and a second rod receiving opening 17 which are both designed to receive a free end 18a, 19a of a corresponding rod 18, 19.

[0058] The housing 12 is joined at its upper end to an upper closing plate 20 which also forms part of the actuator frame. As shown in figure 3, this is achieved by a bolt 21 which extends through a curved slot 22 in the housing 12 into a bolt opening (not shown) in the upper closing plate 20. This curved slot allows a limited rotation of the housing 12 with respect to the rest of the actuator 10 about the vertical axis 15. This allows better aligning the elongated access slot 14 with an access opening 50 provided in the gate post 1. This access opening 50 is described below with respect to figures 9A and 9B.

[0059] The upper closing plate 20 has a stepped outer area 23 and the electromotor 5 has a similar stepped outer area 24. These stepped areas are better shown in figure 7A and allow the placing of a cylindrical cover 25 to shield the brake mechanism 8. It will be appreciated that the cover 25 is not necessarily cylindrical and forms another frame component. As also shown in figure 7A, the upper closing plate 20 has a first rod receiving opening 26 and a second rod receiving opening 27 which are both designed to receive a free end 18b, 19b of the corresponding rod 18, 19.

[0060] The uncoupling mechanism 9 comprises a base body 28. A horizontal cross-section through the assembled base body 28 is shown in figure 5. Figure 5 shows that the base body 28 is provided with a threaded opening 29 through which the rod 19 extends. As shown in figure 4, the rod 19 is also threaded on its outer surface and is fixed at its ends to the closing plates 11, 20. As shown in figure 5, an outer contour of the base body 28 matches the shape of the housing 12 thus preventing a rotation of the base body 28 with respect to the frame 11, 12, 20. Figure 3 further shows that the free end 19a of the rod 19 is accessible and a tool opening 30 (e.g. a hexagonal hole) is provided to allow insertion of a tool (e.g. a hex key or Allen key) thus enabling to rotate the rod 19 about the vertical axis 15. The threads on the rod 19 and the base body opening 29 and the form-fitting of the base body 28 and the housing 12 ensure that a rotation of the rod 19 results in a sliding motion of the base body 28 in the vertical direction.

[0061] A first height position of the base body 28 is illustrated in figure 8A and a second different height position of the base body 28 is illustrated in figure 8B. The threaded rod 19 and non-rotatable base body 28 thus form a height adjustment mechanism to allow varying the height of (part of) the uncoupling mechanism. This allows better aligning the worm 31 with the access opening 50 provided in the gate post 1. This access opening 50 is described below with respect to figures 9A and 9B.

[0062] In the illustrated embodiment, the uncoupling mechanism 9 further comprises a worm drive having a worm 31 and a worm wheel 32. These are shown in figure 5. The worm wheel 32 is placed around the rod 18 in a form-fitting manner such that any rotation of the worm wheel 32 causes a rotation of the rod 18. This may be achieved by relying on a non-circular rod 18, e.g. a hexagonal rod. The worm 31 is provided with a tooling opening 33 (e.g. a hexagonal opening) to allow insertion of a tool (e.g. a hex key or Allen key) thus enabling to rotate the worm 31. The worm gear allows to transfer the direction of rotational motion. More specifically, it allows the worm 31 to be operated by inserting a tool in a second direction 34 which, in use, will typically substantially coincide with a horizontal direction. The worm 31 is thus rotatable about the horizontal direction and via the worm drive this is converted into a rotation of the rod 19 about the vertical direction 15.

[0063] The rod 18 has a free upper end 18b which is provided with a threaded area and which engages a threaded area in the first rod receiving opening 26 of the upper closing plate 20. This is best shown in figures 6 to 8B. The threaded engagement between the rod 18 and the static upper closing plate 20 means that a rotational motion of the rod 18 causes a sliding motion of the rod 18, in particular of the free end 18b thereof. This is best shown when comparing figures 7A and 7B. Figure 7A shows the coupled state of the uncoupling mechanism 9 where the worm 31 has not been rotated. In this normal state, the free end 18b is flush with the upper side 20a of the closing plate 20 (alternatively, the free end 18b could be recessed deeper in the opening 26). When the worm 31 is rotated, the rod 18 slides in the vertical direction thus moving the uncoupling mechanism 9 to its uncoupled state which is shown in figure 7B. The free end 18b thus protrudes with respect to the surface 20a of the closing plate 20 thereby pushing a base plate 35 away from the closing plate 20. In this way, a distance is created between the surface 20a and the surface 35a which, as described below, will uncouple the brake mechanism 8.

[0064] The electromotor 5, preferably a brushless DC motor, generally comprises a rotor 36 and a stator 37. These components are shown in cross-section in figure 6. A bearing 38, in particular a ball bearing, is provided between the rotor 36 and stator 37 to reduce friction and allow an improved rotation of the rotor 36. The rotor 36 forms the central axis of the electromotor 5 and extends between a lower end 36a and an upper end (not shown). The upper end of the rotor 36 is coupled to the gearing 6. The lower end 36a is coupled to the brake mechanism 8. Specific details of the electromotor 5 are not relevant in the context of the present invention and are generally known to the skilled person.

[0065] The brake mechanism 8 comprises two friction discs, namely a first friction disc 39 that is fixed to the free end 36a of the rotor 36 and a second friction disc 40 which is fixed (directly or indirectly) to the stator 37. Friction disc 39 is thus locked to the rotor 36 and rotated concurrently therewith, while friction disc 40 remains stationary with respect to the rotor 36. Friction disc 40 is coupled to the base plate 35 by support pins 41 so that these elements are jointly slidable in the vertical direction 15 when using the uncoupling mechanism 9. This is clear when comparing figures 7A and 7B where the friction disc 40 is spaced from an electromagnet assembly 42 in figure 7A and not spaced from this assembly 42 in figure 7B.

[0066] The brake mechanism 8 further comprises a base body 42 in which a coil 43 is provided that is part of the electromagnet assembly. The coil 43, when activated, attracts the friction disc 40. To this end, the friction disc 40 is preferably composed of two layers 40a and 40b.The second layer 40b is made from a magnetic material that is attracted by the electromagnet, whereas the first layer 40a is made of an abrasive material to have the desired friction. The base body 42 also comprises one or more biasing members 44 (e.g. a compression spring in the illustrated embodiment) which urges the friction disc 40 away from the base body 42 and towards the other friction disc 39.

[0067] Figures 7A and 7B further show how the uncoupling mechanism 9 and the brake mechanism 9 are fixed together. To this end, one or more threaded fastening members 45 extend through the upper closing plate 20 and into threaded holes 46 provided in the base body 42. Hollow rods 47 may be placed around the threaded fastening members 45 to avoid overtightening the fasteners 45. Along the length of the threaded fastening members 45, an abutment wall 48 is also positioned. This wall 48 limits the vertical sliding motion of the base plate 35 and thus also of the friction ring 40. The wall 48 also acts as a fixed stop to prevent any sliding of the friction ring 39 due to the biasing members 44 urging the friction ring 40 away from base body 42.

[0068] The operation of the gate actuator 10 is described in the following. In case no power is supplied, the electromagnet 43 is not active. The biasing member(s) 44 urges the friction discs 39, 40 against one another. The abutment wall 48 acts as a stop. This situation is shown in figure 7A. Due to the exerted biasing force and the static friction between the rings 39, 40 the rotor 36 cannot rotate. The brake mechanism 8 is thus engaged and the closure member 2 remains static. When power is supplied to the actuator 10, the electromagnet 43 is activated and attracts the friction ring 40 against the force of the biasing member 44. A gap is created between the friction rings 39, 40 (shown in figure 6) allowing the rotor 36 to rotate thus actuating the closure member 2. This is the normal operation of the gate actuator 10.

[0069] In cases where there is a power failure, the brake mechanism 8 is thus engaged and the closure member 2 remains static. When a user nevertheless has to move the closure member 2, the uncoupling mechanism 9 is used. The user then rotates the worm 31 which causes the base plate 35 to be slid towards the base body 42. The friction ring 40 is slid jointly with the base plate 35 against the force of the biasing member 44. A gap is created between the friction rings 39, 40 (shown in figure 7B) allowing the rotor 36 to rotate thus allowing the user to manually move the closure member 2.

[0070] It will be readily appreciated that the roles of the friction discs 39, 40 could be reversed in the sense that friction disc 4 could remain static and that the uncoupling mechanism 9 acts directly or indirectly on friction disc 39.

[0071] It will be further appreciated that the roles of the electromagnet 43 and the biasing member 44 could be reversed in the sense that the biasing member 44 could attract a friction disc and the electromagnet 43 repulses this disc. Furthermore, the electromagnet and / or biasing member could also act an different ones of the friction disc, e.g. one element operating on each or both elements operating on disc 39.

[0072] Figures 9A and 9B illustrate the provision of an access opening 50 in the gate post 1. As best shown in figure 9B, the access opening 50 is normally sealed by a cap 51 which can be pivoted to open the opening 50. Naturally other kinds of caps are known and suitable. Once open, the access opening 50 provides access to the worm 31. A space may be provided inside the first member 1 to store the tool 52 (e.g. the hex key) to be used in order to operate the worm 31. A lock cylinder 49 is also provided which allows, when unlocked, to remove a wall panel 53 in order to provide access to the interior of the first member 1. Once the wall panel 53 is removed, the height adjustment mechanism (i.e. the rod 19) can be accessed to adjust the height of the base body 28 as needed in order to align with the access opening 50.

[0073] 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.

Examples

Embodiment Construction

[0048]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.

[0049]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.

[0050]Moreover, the terms top, bottom, over, under and the like in the description and the claims are used fo...

Technical field

[0001] The present invention generally relates to an electric gate actuator electric gate actuator for actuating a closure system having a first member, in particular a gate post, and a second member, in particular a gate. The closure members may be hingedly connected to each other or may be slidable with respect to one another. The present invention further relates to a closure system comprising such an electric gate actuator.Background art

[0002] Various types of gate actuators are known in the art, for example spring-biased gate actuators as disclosed in WO 2012 / 103572 which serve to automatically close the gate; hydraulically damped spring-biased gate actuators as disclosed in WO 2018 / 228729 which also serve to automatically close the gate; and electric gate actuators as disclosed in WO 2019 / 048359 which serve to both open or close the gate. The present invention is generally related to gate actuators of the latter kind which are operated by an electromotor. Such gate actuators are also commonly referred to as gate openers and may be used both in the context of hinged closure systems or slidable closure systems.

[0003] A known electric gate comprises: a frame configured to be mounted to a first member of the closure system (e.g. a gate post); an electromotor mounted on the frame, the electromotor comprising: a rotor, a stator and a brake mechanism which comprises: a first friction disc rotatably fixed to the rotor, a second friction disc rotatably fixed to the stator, and a biasing member urging the friction discs against one another to prevent rotation of the rotor when insufficient power is supplied to the electromotor; a driver mounted on the frame and configured to transfer a rotation (e.g. directly transferring the rotation in case of a hinged closure system or involving a rack-and-pinion mechanism in case of slidable closure system) of the rotor to the second member (e.g. a gate); and a mechanical uncoupling system mounted on the frame for uncoupling the electromotor.

[0004] The brake mechanism is used to prevent unwanted or accidental opening or closing of the gate when no or insufficient power is supplied. More specifically, when the gate is closed, various forces may be exerted thereon (e.g. wind load, a person pushing on the gate, etc.). The brake mechanism ensures that such forces do not readily open the gate. To this end, two friction discs are urged together by the biasing member thereby creating a friction force between them. This friction prevents the rotation of the rotor even when a force is exerted on the gate.

[0005] The main advantage of such a brake system is that it is passive in the sense that it requires no power to operate. However, a known issue with such a brake is that the gate remains closed when there is a power failure. To this end, a manually operable mechanical unlocking system is present which allows uncoupling the electromotor from the closure system and particularly allows to disengage one or more components located between the electromotor and the driver.Disclosure of the invention

[0006] It is an aim of the present invention to provide an improved mechanical uncoupling system.

[0007] To this aim the gate actuator according to the present invention is characterized in that the mechanical uncoupling system engages one of the friction discs to move the frictions discs away from one another against the force of the biasing member.

[0008] A main advantage of the mechanical uncoupling system according to the present invention is its simplicity and reliability. By acting directly on the brake mechanism, the system enables disabling the brake thus allowing free rotation of the closure system even in the absence of power. However, contrary to the known uncoupling systems, there is no need to actually uncouple one or more components located between the electromotor and the driver, which components are crucial for the normal operation of the gate actuator. There is thus no risk that using the mechanical uncoupling system damages or wrongly re-engaging the mechanical uncoupling system could interfere with the normal working of the gate actuator.

[0009] An embodiment of the gate actuator is characterized in that the mechanical uncoupling system comprises a rod which is mounted on the frame, the rod having: a free end which engages (either directly or indirectly by one or more intermediary elements) said one of the friction discs; and a thread which engages a corresponding thread formed on the frame such that a rotation of the rod causes a sliding motion of the free end of the rod.

[0010] In this embodiment, the mechanical uncoupling system comprises relies on a rod that is slidably mounted on the frame between a rest state and an actuated state. In the rest state, the rod is not engaging the friction disc, whereas in the actuated state, the rod has slid the friction disc to disengage both friction discs. The threads further prevent that the rod would be slid to its rest state due to the force exerted by the biasing member. In other words, a user can release the rod once it has been slid to its actuated state.

[0011] An embodiment of the gate actuator is characterized in that the mechanical uncoupling system further comprises a worm drive having: a manually operable worm; and a worm wheel which engages said worm, the rod being irrotatably coupled to the worm wheel.

[0012] In this embodiment, the mechanical uncoupling system further comprises a worm drive to which the rod is coupled in a non-rotatable fashion. In other words, the rotation of the worm wheel causes a same rotation of the rod and vice versa.

[0013] The worm drive changes the rotational direction of motion. As such, whereas the rod is typically oriented vertically (in line with the gate post or gate) and thus rotates about the vertical axis, the worm drive enables operating the mechanical uncoupling system by means of rotating the worm about a different axis, e.g. a horizontal axis. This makes it easier to access the mechanical uncoupling system, especially considering that the end of the rod opposite the free end may not be accessible in case the gate actuator is mounted inside the gate or gate post. The worm drive thus allows to use a dedicated tool that can grip or engage with the worm in a horizontal plane as opposed to a wrench to grip the vertical rod and which would require sufficient space in the horizontal plane to rotate the wrench.

[0014] An embodiment of the gate actuator is characterized in that the electromotor comprises a base plate which is slidable with respect to the frame, said one of the friction discs being fixed to the base plate, wherein the free end of the rod contacts the base plate and wherein a rotation of the rod causes the base plate to slide with respect to the frame, wherein, preferably, the first friction disc is interposed between the base plate and the second friction disc which is fixed to the base plate.

[0015] The use of a base plate as an intermediary between the rod and the friction disc provides design freedom and flexibility. More specifically, the friction disc can be designed and the material can be chosen without having to take into account a contact with the rod and the local pressure that rod contact would create. Rather, the base plate is contact by the rod and handles the locally high pressure. Placing the first friction disc between the base plate and the second friction disc in essence results in a cage which surrounds the first friction disc, which cage is then slidable by being engaged by the rod.

[0016] An embodiment of the gate actuator is characterized in that the electromotor comprises an electromagnet and one of the friction discs comprises a magnetic element which is configured to be attracted to the electromagnet when sufficient power is supplied to the electromotor to overcome the biasing member thereby moving the friction discs away from one another.

[0017] The electromagnet forms part of the normal operation of the gate actuator. More specifically, when power is supplied, the electromagnet attracts one of the friction discs thus disengaging the brake mechanism against the force of the biasing member.

[0018] As used herein, the term "magnetic element" is intended to refer to an element or part thereof which is attracted by an electromagnet, such as manufactured (in part) of a (soft) ferromagnetic or ferrimagnetic material.

[0019] An embodiment of the gate actuator is characterized in that the second friction disc comprises a first disc layer facing the first friction disk and a second layer comprising said magnetic element, the first layer preferably being formed from stainless steel or a ceramic material and the second layer preferably being formed from a ferromagnetic material.

[0020] A two layer friction disc allows to optimize the material choice with one layer being designed to be sufficiently magnetically attracted to the electromagnet, whilst the other layer can be designed to provide the desired amount of friction and / or to withstand potential wear and tear as part of the friction brake.

[0021] An embodiment of the gate actuator is characterized in that the electromotor has an output shaft protruding from a side of the electromotor and the brake mechanism and the mechanical uncoupling system are positioned on the opposite side of the output shaft.

[0022] Placing the brake mechanism on the other side of the electromotor than the output shaft reduces the risk of these components interfering with one another.

[0023] An embodiment of the gate actuator is characterized in that the electric gate actuator further comprises a gearing mounted on the frame and interposed between the rotor of the electromotor and the driver, wherein the mechanical uncoupling system and the gearing are preferably placed on opposite sides of the electromotor.

[0024] The use of a gearing (or gearbox) serves to reduce the speed and increase the torque of a compact electromotor so that the gate can be actuated with sufficient force. In an embodiment, the gearing has a reduction that is between 1:100 and 1:1000, for example 1:200 or 1:400. Placing the brake mechanism on the other side of the electromotor than the gearing reduces the risk of these components interfering with one another.

[0025] An embodiment of the gate actuator is characterized in that the electromotor is a brushless DC motor.

[0026] A brushless DC motor has multiple advantages over conventional brushed DC motors, such as a compact design, reduced wear and tear and a lower maintenance, high efficiency, etc.

[0027] An embodiment of the gate actuator is characterized in that the electric gate actuator further comprises a gearing mounted on the frame and interposed between the rotor of the electromotor and the driver, the gearing having a ratio between 1:400 and 1:1000, preferably between 1:500 and 1:800, the ratio more preferably being between 1:600 and 1:700.

[0028] It is advantages to avoid too high a gearing since, when the uncoupling mechanism is activated, a user still has to manually move the closure system. That is, the gate actuator has to be back-drivable. A too high gearing causes issues with the back-drivability as a too high force is required to move the closure system. A too low gearing on the other hand requires a more powerful electromotor which is thus less compact, more expensive, etc.

[0029] An embodiment of the gate actuator is characterized in that the first friction disc is not slidable with respect to the frame and the second friction disc is slidable with respect to the frame between an engaging position in which the friction discs engage one another and a disengaging position in which the friction discs do not engage one another.

[0030] The use of slidable friction discs and a biasing member is a simple and reliable system to form a brake mechanism which involves no complex force transfer and / or complex multi-directional motions.

[0031] An embodiment of the gate actuator is characterized in that a biasing force of the biasing member and the static coefficient of friction between the frictions discs are such that the brake mechanism prevents rotation of the rotor up to a torque of at least 0,5 N·m and preferably at least 1 N·m, acting on the rotor.

[0032] The static friction between the friction discs is given by F f = µF N where µ is the static coefficient of friction and F N is the normal force which is determined by the biasing force of the biasing member. As the brake mechanism acts directly on the electromotor, only a relatively low friction is required as there is commonly a gearing present between the electromotor and the driver.

[0033] The specific value of torque resistance is mainly determined in function of the gearing ratio and the potential load expected on the closure system. In case of a hinged closure system, the wind load is typically estimated in the order of magnitude of 1000 to 2000 N. The brake mechanism has to thus be able to keep the closure system locked for such loads. This may be achieved with a brake mechanism that prevents rotation of the rotor up to a torque of 2-3 N·m with a gearing ratio between 1:600 and 1:700.

[0034] The advantages of the embodiments described above are also achieved with a closure system comprising: a first member, in particular a gate post; a second member, in particular a gate, that are particularly hingedly connected to each other by at least one hinge; and an electric gate actuator as described above mounted in the first member with the driver engaging the second member or said at least one hinge.

[0035] It will be readily appreciated that the driver can be directly coupled to the gate (e.g. using a sliding rail as disclosed in figures 8 to 10C of WO 2018 / 228729) or can be coupled to the eyebolt hinge (e.g. as in WO 2019 / 048359 or as in figures 1A to 3B of WO 2018 / 228729). Generally speaking, the electric gate actuator can be surface mounted on the outside of a gate post (e.g. as in WO 2019 / 048359). However, in the context of the present invention, the electric gate actuator is preferably mounted inside the first member, e.g. inside the gate post. This improves the security of the closure system as the electric gate actuator cannot be easily accessed for persons with ill intent. Furthermore, the electric gate actuator is also better protected from atmospheric influences. The visual result of integrating the electric gate actuator is also desired by users.

[0036] An embodiment of the gate actuator is characterized in that the mechanical uncoupling system comprises height adjustment means allowing to vary the placement of (part of) the mechanical uncoupling system with respect to the first member.

[0037] This makes it easier to rely on standardly manufactured first members (e.g. gate posts) having an access opening at a fixed place while at the same time allowing to vary the gate actuator placement within the first member as needed. Especially in the context of outdoor gates, there is a need to be able to vary the gate actuator placement to account for height or horizontal distances between various elements of the closure system. As such, having part of the mechanical uncoupling system that is adjustable allows aligning it correctly with the access opening.

[0038] An embodiment of the gate actuator is characterized in that the mechanical uncoupling system comprising a base body which is slidably mounted on the frame, the base body having a threaded opening, and in that the height adjustment means comprise: guiding means which guide the base body; and a manually rotatable threaded rod engaging the threaded opening, wherein a rotation of the threaded rod causes a sliding motion of the base body.

[0039] The use of a base body allows to mount all needed components of the mechanical uncoupling system thereon and to have all these simultaneously slidable as desired. A threaded rod and threaded opening are well known means to transfer a rotational motion into a sliding motion.

[0040] An embodiment of the gate actuator is characterized in that the guiding means comprise a housing in which the base body is form-fitting.

[0041] The use of form-fitting elements avoids the need to provide additional rotation restriction elements.

[0042] An embodiment of the gate actuator is characterized in that the worm is mounted on the base body.

[0043] The worm is thus slidable together with the base body.

[0044] An embodiment of the gate actuator is characterized in that the first member comprises an access opening which allows access to the mechanical uncoupling system, in particular to the worm.

[0045] This improves user convenience.

[0046] 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 claimsBrief description of the drawings

[0047] The invention will be further explained by means of the following description and the appended figures. Figure 1 shows a perspective view of a closure system according to the present invention. Figure 2 shows a front view of a gate actuator according to the present invention. Figure 3 shows the brake and uncoupling mechanism present in the gate actuator according to the present invention. Figure 4 shows an exploded view of figure 3. Figure 5 shows a horizontal cross-section through the uncoupling mechanism present in the gate actuator according to the present invention. Figure 6 shows a partial vertical cross-section through the gate actuator according to the present invention in the activated state. Figures 7A and 7B show a same detail of the vertical cross-section through the brake mechanism in the coupled and uncoupled state. Figures 8A and 8B show a same partial vertical cross-section through the gate actuator according to the present invention with the uncoupling mechanism at different heights. Figures 9A and 9B show different views of an access opening in the gate post providing access to the uncoupling mechanism. Description of the invention

[0048] 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.

[0049] 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.

[0050] 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.

[0051] 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.

[0052] 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".

[0053] The invention generally relates to an electric gate actuator 10 for closing a closure system having a first member and a second member that are hingedly connected to each other as shown in figure 1. The first member is typically a fixed support 1, such as a wall or a gate post, while the second member 2 is typically a moveable closure wing 2, such as a gate or a door. The members 1, 2 are connected by one or more hinges 3. The electric gate actuator 10 is typically used in outdoor applications (e.g. as part of a fence). The electric gate actuator 10 is primarily designed to be inserted in a hollow tubular member which may be part of either closure member, although the electric gate actuator 10 may also be surface mounted. In the illustrated embodiments, the electric gate actuator 10 is fixed with respect to the gate post 1 and a driver 4 is present to couple the electric gate actuator 10 to the gate wing 2. However, a reversal is also possible.

[0054] Furthermore, although the actuator 10 is described in relation to a hinged closure system, it may be used in the context of a slidable closure system as well.

[0055] The electric gate actuator 10 is shown in figure 2. The illustrated actuator 10 generally comprises an electromotor 5, a gearing 6 and an output shaft 7. The electromotor 5, preferably a brushless DC motor, is advantageous because of its compactness, which allows it to be incorporated inside the gate post 1. In an embodiment, the gearing 6 has a ratio between 1:400 and 1:1000, e.g. 1:600 or 1:700, such that an output of the electromotor 5 is amplified to the output shaft 7. The driver 4 is coupled directly or indirectly to the output shaft 7.

[0056] The illustrated actuator 10 further comprises a brake mechanism 8 and an uncoupling mechanism 9 which are the main aspects of the present invention. These mechanisms are shown in detail in figure 3 and in exploded view in figure 4.

[0057] The actuator 10 generally comprises a frame that is fixed directly or indirectly to the closure system. This frame is generally static and is formed by different elements in the illustrated embodiment. The frame comprises a lower end closing plate 11 to which a housing 12 is bolted by means of bolts 13. The housing 12 is also a frame component and acts as a housing for the uncoupling mechanism 9. The housing 12 extends in a first direction 15 (indicated in figure 2) which, in use, will typically substantially coincide with the vertical direction. An elongated access slot 14 is provided in the housing 12, which slot 14 extends in the vertical direction 15. The lower closing plate 11 is provided with, besides the multiple bolt openings, also two rod receiving openings. More specifically, a first rod receiving opening 16 and a second rod receiving opening 17 which are both designed to receive a free end 18a, 19a of a corresponding rod 18, 19.

[0058] The housing 12 is joined at its upper end to an upper closing plate 20 which also forms part of the actuator frame. As shown in figure 3, this is achieved by a bolt 21 which extends through a curved slot 22 in the housing 12 into a bolt opening (not shown) in the upper closing plate 20. This curved slot allows a limited rotation of the housing 12 with respect to the rest of the actuator 10 about the vertical axis 15. This allows better aligning the elongated access slot 14 with an access opening 50 provided in the gate post 1. This access opening 50 is described below with respect to figures 9A and 9B.

[0059] The upper closing plate 20 has a stepped outer area 23 and the electromotor 5 has a similar stepped outer area 24. These stepped areas are better shown in figure 7A and allow the placing of a cylindrical cover 25 to shield the brake mechanism 8. It will be appreciated that the cover 25 is not necessarily cylindrical and forms another frame component. As also shown in figure 7A, the upper closing plate 20 has a first rod receiving opening 26 and a second rod receiving opening 27 which are both designed to receive a free end 18b, 19b of the corresponding rod 18, 19.

[0060] The uncoupling mechanism 9 comprises a base body 28. A horizontal cross-section through the assembled base body 28 is shown in figure 5. Figure 5 shows that the base body 28 is provided with a threaded opening 29 through which the rod 19 extends. As shown in figure 4, the rod 19 is also threaded on its outer surface and is fixed at its ends to the closing plates 11, 20. As shown in figure 5, an outer contour of the base body 28 matches the shape of the housing 12 thus preventing a rotation of the base body 28 with respect to the frame 11, 12, 20. Figure 3 further shows that the free end 19a of the rod 19 is accessible and a tool opening 30 (e.g. a hexagonal hole) is provided to allow insertion of a tool (e.g. a hex key or Allen key) thus enabling to rotate the rod 19 about the vertical axis 15. The threads on the rod 19 and the base body opening 29 and the form-fitting of the base body 28 and the housing 12 ensure that a rotation of the rod 19 results in a sliding motion of the base body 28 in the vertical direction.

[0061] A first height position of the base body 28 is illustrated in figure 8A and a second different height position of the base body 28 is illustrated in figure 8B. The threaded rod 19 and non-rotatable base body 28 thus form a height adjustment mechanism to allow varying the height of (part of) the uncoupling mechanism. This allows better aligning the worm 31 with the access opening 50 provided in the gate post 1. This access opening 50 is described below with respect to figures 9A and 9B.

[0062] In the illustrated embodiment, the uncoupling mechanism 9 further comprises a worm drive having a worm 31 and a worm wheel 32. These are shown in figure 5. The worm wheel 32 is placed around the rod 18 in a form-fitting manner such that any rotation of the worm wheel 32 causes a rotation of the rod 18. This may be achieved by relying on a non-circular rod 18, e.g. a hexagonal rod. The worm 31 is provided with a tooling opening 33 (e.g. a hexagonal opening) to allow insertion of a tool (e.g. a hex key or Allen key) thus enabling to rotate the worm 31. The worm gear allows to transfer the direction of rotational motion. More specifically, it allows the worm 31 to be operated by inserting a tool in a second direction 34 which, in use, will typically substantially coincide with a horizontal direction. The worm 31 is thus rotatable about the horizontal direction and via the worm drive this is converted into a rotation of the rod 19 about the vertical direction 15.

[0063] The rod 18 has a free upper end 18b which is provided with a threaded area and which engages a threaded area in the first rod receiving opening 26 of the upper closing plate 20. This is best shown in figures 6 to 8B. The threaded engagement between the rod 18 and the static upper closing plate 20 means that a rotational motion of the rod 18 causes a sliding motion of the rod 18, in particular of the free end 18b thereof. This is best shown when comparing figures 7A and 7B. Figure 7A shows the coupled state of the uncoupling mechanism 9 where the worm 31 has not been rotated. In this normal state, the free end 18b is flush with the upper side 20a of the closing plate 20 (alternatively, the free end 18b could be recessed deeper in the opening 26). When the worm 31 is rotated, the rod 18 slides in the vertical direction thus moving the uncoupling mechanism 9 to its uncoupled state which is shown in figure 7B. The free end 18b thus protrudes with respect to the surface 20a of the closing plate 20 thereby pushing a base plate 35 away from the closing plate 20. In this way, a distance is created between the surface 20a and the surface 35a which, as described below, will uncouple the brake mechanism 8.

[0064] The electromotor 5, preferably a brushless DC motor, generally comprises a rotor 36 and a stator 37. These components are shown in cross-section in figure 6. A bearing 38, in particular a ball bearing, is provided between the rotor 36 and stator 37 to reduce friction and allow an improved rotation of the rotor 36. The rotor 36 forms the central axis of the electromotor 5 and extends between a lower end 36a and an upper end (not shown). The upper end of the rotor 36 is coupled to the gearing 6. The lower end 36a is coupled to the brake mechanism 8. Specific details of the electromotor 5 are not relevant in the context of the present invention and are generally known to the skilled person.

[0065] The brake mechanism 8 comprises two friction discs, namely a first friction disc 39 that is fixed to the free end 36a of the rotor 36 and a second friction disc 40 which is fixed (directly or indirectly) to the stator 37. Friction disc 39 is thus locked to the rotor 36 and rotated concurrently therewith, while friction disc 40 remains stationary with respect to the rotor 36. Friction disc 40 is coupled to the base plate 35 by support pins 41 so that these elements are jointly slidable in the vertical direction 15 when using the uncoupling mechanism 9. This is clear when comparing figures 7A and 7B where the friction disc 40 is spaced from an electromagnet assembly 42 in figure 7A and not spaced from this assembly 42 in figure 7B.

[0066] The brake mechanism 8 further comprises a base body 42 in which a coil 43 is provided that is part of the electromagnet assembly. The coil 43, when activated, attracts the friction disc 40. To this end, the friction disc 40 is preferably composed of two layers 40a and 40b.The second layer 40b is made from a magnetic material that is attracted by the electromagnet, whereas the first layer 40a is made of an abrasive material to have the desired friction. The base body 42 also comprises one or more biasing members 44 (e.g. a compression spring in the illustrated embodiment) which urges the friction disc 40 away from the base body 42 and towards the other friction disc 39.

[0067] Figures 7A and 7B further show how the uncoupling mechanism 9 and the brake mechanism 9 are fixed together. To this end, one or more threaded fastening members 45 extend through the upper closing plate 20 and into threaded holes 46 provided in the base body 42. Hollow rods 47 may be placed around the threaded fastening members 45 to avoid overtightening the fasteners 45. Along the length of the threaded fastening members 45, an abutment wall 48 is also positioned. This wall 48 limits the vertical sliding motion of the base plate 35 and thus also of the friction ring 40. The wall 48 also acts as a fixed stop to prevent any sliding of the friction ring 39 due to the biasing members 44 urging the friction ring 40 away from base body 42.

[0068] The operation of the gate actuator 10 is described in the following. In case no power is supplied, the electromagnet 43 is not active. The biasing member(s) 44 urges the friction discs 39, 40 against one another. The abutment wall 48 acts as a stop. This situation is shown in figure 7A. Due to the exerted biasing force and the static friction between the rings 39, 40 the rotor 36 cannot rotate. The brake mechanism 8 is thus engaged and the closure member 2 remains static. When power is supplied to the actuator 10, the electromagnet 43 is activated and attracts the friction ring 40 against the force of the biasing member 44. A gap is created between the friction rings 39, 40 (shown in figure 6) allowing the rotor 36 to rotate thus actuating the closure member 2. This is the normal operation of the gate actuator 10.

[0069] In cases where there is a power failure, the brake mechanism 8 is thus engaged and the closure member 2 remains static. When a user nevertheless has to move the closure member 2, the uncoupling mechanism 9 is used. The user then rotates the worm 31 which causes the base plate 35 to be slid towards the base body 42. The friction ring 40 is slid jointly with the base plate 35 against the force of the biasing member 44. A gap is created between the friction rings 39, 40 (shown in figure 7B) allowing the rotor 36 to rotate thus allowing the user to manually move the closure member 2.

[0070] It will be readily appreciated that the roles of the friction discs 39, 40 could be reversed in the sense that friction disc 4 could remain static and that the uncoupling mechanism 9 acts directly or indirectly on friction disc 39.

[0071] It will be further appreciated that the roles of the electromagnet 43 and the biasing member 44 could be reversed in the sense that the biasing member 44 could attract a friction disc and the electromagnet 43 repulses this disc. Furthermore, the electromagnet and / or biasing member could also act an different ones of the friction disc, e.g. one element operating on each or both elements operating on disc 39.

[0072] Figures 9A and 9B illustrate the provision of an access opening 50 in the gate post 1. As best shown in figure 9B, the access opening 50 is normally sealed by a cap 51 which can be pivoted to open the opening 50. Naturally other kinds of caps are known and suitable. Once open, the access opening 50 provides access to the worm 31. A space may be provided inside the first member 1 to store the tool 52 (e.g. the hex key) to be used in order to operate the worm 31. A lock cylinder 49 is also provided which allows, when unlocked, to remove a wall panel 53 in order to provide access to the interior of the first member 1. Once the wall panel 53 is removed, the height adjustment mechanism (i.e. the rod 19) can be accessed to adjust the height of the base body 28 as needed in order to align with the access opening 50.

[0073] 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.

Examples

Embodiment Construction

[0048]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.

[0049]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.

[0050]Moreover, the terms top, bottom, over, under and the like in the description and the claims are used fo...

Claims

1. An electric gate actuator (10) for actuating a closure system having a first member (1) and a second member (2), the gate actuator comprising: - a frame configured to be mounted to the first member; - an electromotor (5) mounted on the frame, the electromotor comprising: a rotor (36), a stator (37) and a brake mechanism (8) which comprises: - a first friction disc (39) rotatably fixed to the rotor, - a second friction disc (40) rotatably fixed to the stator, and - a biasing member (44) urging the friction discs against one another to prevent rotation of the rotor when insufficient power is supplied to the electromotor; - a driver (4) mounted on the frame and configured to transfer a rotation of the rotor to the second member; and - a mechanical uncoupling system (9) mounted on the frame for uncoupling the electromotor, characterized in that the mechanical uncoupling system engages one of the friction discs to move the frictions discs away from one another against the force of the biasing member.

2. The gate actuator according to claim 1, characterized in that the mechanical uncoupling system comprises a rod (18) which is mounted on the frame, the rod having: - a free end (18b) which engages said one of the friction discs; and - a thread which engages a corresponding thread (26) formed on the frame such that a rotation of the rod causes a sliding motion of the free end of the rod.

3. The gate actuator according to claim 2, characterized in that the mechanical uncoupling system further comprises a worm drive having: - a manually operable worm (31); and - a worm wheel (32) which engages said worm, the rod being irrotatably coupled to the worm wheel.

4. The gate actuator according to claim 2 or 3, characterized in that the electromotor comprises a base plate (35) which is slidable with respect to the frame, said one of the friction discs being fixed to the base plate, wherein the free end of the rod contacts the base plate and wherein a rotation of the rod causes the base plate to slide with respect to the frame, wherein, preferably, the first friction disc is interposed between the base plate and the second friction disc which is fixed to the base plate.

5. The gate actuator according to any one of the preceding claims, characterized in that the electromotor comprises an electromagnet (43) and one of the friction discs comprises a magnetic element which is configured to be attracted to the electromagnet when sufficient power is supplied to the electromotor to overcome the biasing member thereby moving the friction discs away from one another.

6. The gate actuator according to claim 5, characterized in that the second friction disc comprises a first disc layer (40a) facing the first friction disk and a second layer (40b) comprising said magnetic element, the first layer preferably being formed from stainless steel or ceramic and the second layer preferably being formed from a ferromagnetic material.

7. The gate actuator according to any one of the preceding claims, characterized in that the electric gate actuator further comprises a gearing (6) mounted on the frame and interposed between the rotor of the electromotor and the driver, wherein the mechanical uncoupling system and the gearing are preferably placed on opposite sides of the electromotor, wherein the gearing preferably has a ratio between 1:400 and 1:1000, more preferably between 1:500 and 1:800, the ratio most preferably being between 1:600 and 1:700.

8. The gate actuator according to any one of the preceding claims, characterized in that: - the electromotor is a brushless DC motor; and / or - the first friction disc is not slidable with respect to the frame and the second friction disc is slidable with respect to the frame between an engaging position in which the friction discs engage one another and a disengaging position in which the friction discs do not engage one another9. The gate actuator according to any one of the preceding claims, characterized in that a biasing force of the biasing member and the static coefficient of friction between the frictions discs are such that the brake mechanism prevents rotation of the rotor up to a torque of at least 0,5 N·m and preferably at least 1 N·m, acting on the rotor.

10. A closure system comprising a first member (1), in particular a gate post, and a second member (2), in particular a gate, that are particularly hingedly connected to each other by at least one hinge (3), characterized in that the closure system further comprises an electric gate actuator (10) according to any one of the preceding claims mounted in the first member with the driver engaging the second member or said at least one hinge.

11. The closure system according to claim 10, characterized in that the mechanical uncoupling system comprises height adjustment means allowing to vary the placement of the mechanical uncoupling system with respect to the first member.

12. The closure system according to claim 11, characterized in that the mechanical uncoupling system comprising a base body (28) which is slidably mounted on the frame, the base body having a threaded opening (29), and in that the height adjustment means comprise: - guiding means which guide the base body; and - a manually rotatable threaded rod (19) engaging the threaded opening, wherein a rotation of the threaded rod causes a sliding motion of the base body.

13. The closure system according to claim 12, characterized in that the guiding means comprise a housing (12) in which the base body is form-fitting.

14. The closure system according to claim 12 or 13, characterized in that the electric gate actuator is dependent at least on claim 3, and in that the worm is mounted on the base body.

15. The closure system according to any one of claims 11 to 14, characterized in that the first member comprises an access opening (50) which allows access to the mechanical uncoupling system.

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