EP2893106A1

EP2893106A1 - Shock-resistant motorized locking device

Info

Publication number: EP2893106A1
Application number: EP13756626.1A
Authority: EP
Inventors: Jean-Daniel Alzingre; Guillaume KELTZ
Original assignee: Moving Magnet Technologie SA
Current assignee: Cogelec SAS
Priority date: 2012-09-04
Filing date: 2013-07-30
Publication date: 2015-07-15
Anticipated expiration: 2033-07-30
Also published as: US20150225983A1; FR2994997A1; EP2893106B1; JP6301928B2; WO2014037639A1; FR2994997B1; JP2015526621A; US10550603B2

Abstract

Locking device comprising a mobile locking member (9), movement of which can be prevented by a blocking member interacting with a motorized lever (5), characterized in that said motorized lever (5) is capable of rotational movement about an axis (7) with respect to the supporting structure (3), the centre of gravity of said lever (5) lying on said axis (7), said lever (5) being kept in a determined stable position and without rigid mechanical contact of the lever (5) with the supporting structure (3) apart from its axis of rotation (7).

Description

MOTORIZED LOCKING DEVICE RESISTANT TO SHOCKS

TECHNICAL FIELD OF THE INVENTION

The invention relates to the field of electrical devices to provide a locking function, such as motorized locks or mechatronic positioning sets, comprising an electric actuating element and a pivoting lever for locking the device.

The present invention relates more particularly the holding of high security locks, having a high resistance to mechanical shocks assenées during an external attack of the device. The invention also relates to a mechatronic system to withstand an external shock or a high frequency vibration, as may be subject to actuators embedded in automobiles or aircraft in an accident. STATE OF THE PRIOR ART

It is known in the state of the art the French patent FR2945065 describing an electronic lock comprising a stator and a rotor rotatably mounted in the stator and a rotor locking member movable between a locking position in which it is engaged with the rotor to block its rotation and a retracted position in which it releases the rotation of the rotor. A movable stop movable between a first position in which it opposes a displacement of the locking member from its locking position and a second position in which the locking member is free to leave its locking position. The movable stop includes a permanently magnetized portion adapted to retain the movable stop in its first position, bearing against a fixed stop without consuming energy when shaking is applied to the lock.

The European patent EP2412901 describes another example of an electronic lock, comprising a stator and a rotor, a rotor locking member and a lever movable between a locking position, and unlocking. An arm memory is rotated between a rest position and storage under the action of a magnet. This arm comes into contact with a mechanical stop.

DISADVANTAGE OF THE PRIOR ART.

In the solutions of electronic locks of the prior art, the locking member is in contact, at rest and in the locking position, with a mechanical stop against which it relies. Therefore, by applying violent or periodic shocks, at a given frequency, it can cause the unblocking of this unexpected body. Shock vibrations applied to the frame are transmitted by the stop to the movable member, and the transmitted energy causes the displacement of this member and the undesired release of the lock.

The skilled person is therefore confronted with a paradoxical situation where it is necessary to ensure the mechanical locking of a locking member by prohibiting any mechanical contact capable of ensuring a mechanical power transmission. SUMMARY OF THE INVENTION

The invention relates according to its most general meaning a locking device comprising movable locking member whose movement can be prevented by a locking member interacting with a motorized lever characterized in that said motor lever is movable in rotation around an axis relative to the frame, the center of gravity of said lever being located on said axis, said lever being maintained in a determined stable position and without rigid mechanical contact of the lever with the frame out of its axis of rotation. The mechanical wave propagating in a structure during an impact is transferred to the locking lever by the mechanical contact points that it has with the fixed frame. Thus, the shock wave is propagated by the pivot axis on the one hand and by the capture device (at the above-mentioned point of contact) on the other hand. If, due to the balancing of the lever, the device is insensitive to what is transmitted by the axis, it is however sensitive to the force transmitted to the magnetic capture contact. This is similar to what happens in a Newton's pendulum when the end ball is ejected because of the kinetic energy transmitted to it by the dropped ball. Thus, regardless of the capture force generated between the rotary lever and the frame, there will always be a risk of propagation of a shock of sufficient intensity to eject the lever from its stability position and therefore to unlock the lock. The invention thus proposes a locking device comprising an electric actuator moving, inside a frame, a locking lever in rotation about a fixed axis relative to the frame, said lever having its center of gravity on said fixed axis characterized in that said lever is maintained in a determined stable position and, at rest, without rigid mechanical contact of the lever with the frame out of its axis of rotation.

The term "at rest" in the sense of this patent the state of the device when it is locked and no effort is exerted on any of its components.

The notion of rigid mechanical contact is generally implemented when the lever is in mechanical contact with a rigid part integral with the frame. This rigid connection then transmits the energy of the shock to the lever when the frame is struck.

On the contrary, the invention eliminates this rigid connection between frame and lever to make the lever insensitive to any external shock that the shock energy is never transmitted elsewhere than the center of gravity of the lever, which does not generate rotation torque and ensures a holding in position.

Advantageously the stable position is achieved without power consumption.

Various embodiments of this function have been devised. The suspension without rigid contact of the lever can thus be obtained by elastic elements (at least one mechanical spring) or preferably by magnetic elements (connection without contact magnet / magnet or magnet / ferromagnetic material). This suspension can be independent, or integrated with the actuating means of the locking lever. These suspension means without rigid contact create a mechanical filter type "low-pass" which excludes transmission of shocks and vibrations at high frequency (relative to the resonance frequency of the device).

In a particular embodiment, the actuator moving the locking lever also realizes the magnetic force maintaining the stable position of the lever.

The invention also aims to provide an actuator for a locking device driving in rotation about a fixed axis a locking lever characterized in that the locking lever has its center of gravity on said fixed axis and in that that the actuator comprises at least one magnet and has a variable gap to ensure a stable position without power consumption.

Advantageously, the gap is minimum when the lever is in its locked and maximum stability position in the unlocked position. BRIEF DESCRIPTION OF THE FIGURES

We can better understand the relevance of the invention through the description of the following different figures, with different possible variations:

Figure 1 is a perspective representation of a complete electromechanical lock device based on the use of an electric motor and a non-contact stabilizer device according to a first embodiment.

Figures 2a, 2b and 2c are front views in detail of the device of Figure 1, shown in three different states.

Figure 3 is a representation of the invention according to a second embodiment of the actuating device, which intrinsically has a characteristic of stability without current carried by the actuator.

Figures 4a, 4b and 4c are front views in detail of the device of Figure 3, shown in three different states. FIG. 5 is a plot of the torque that is exerted on the locking lever as a function of the supply of the actuator and the position of the lever according to the embodiment presented in FIG. 3.

Figure 6 is a perspective representation of a complete electromechanical lock device in a third embodiment based on the use of a pallet solenoid type actuator and a stabilizer based elastic springs.

FIGS. 7a, 7b and 7c are detail front views in 3 states of the structure shown in FIG. 6. FIGS. 8a and 8b are front detail views according to 2 states of a variant. of the structure presented in Figure 6.

DETAILED DESCRIPTION OF THE EMBODIMENT

The description which follows refers to a nonlimiting example of embodiment in the form of a lock with a movable bolt. But the invention is not limited to the production of a lock and extends to any type of locking device comprising a movable member that can be immobilized transiently via an element interacting with a motorized lever.

The embodiments described in a non-limiting manner relate to a lock (1) comprising a frame (3), and a bolt (9) movable between translation relative to the frame (3), the displacement can be blocked by the engaging the head of a piston (6) in a housing (10).

This piston (6) is movable in translation in a direction perpendicular to the direction of movement of the bolt (109). A spring (126) pushes the piston (6) to rest in the direction of the bolt (9) so as to maintain the piston head in the engaged position in the housing (10). The piston head (6) has a truncated or conical shape, complementary to the shape of the housing (10), so that the displacement of the bolt (9) pushes the piston (6) due to the transverse component (perpendicular the axis of movement of the bolt (9)) of the forces exerted by the inner edge of the housing (10) on the piston head (6). The lock further comprises a lever (5) movable between a locking position in which it prevents the movement of the piston (6), and therefore the release of its head, and an unlocking position where it allows the movement of the piston and the release of the bolt (9) when the piston head (6) is completely out of the housing (10).

The object of the invention is to prevent shocks to the bolt (9) or any other accessible part of the lock propagate with sufficient energy to the lever (5) and causes inadvertent its displacement of the locking position in another position where it no longer ensures the blocking of the movement of the piston (6).

Figures 1, 2a, 2b and 2c show a motorized locking device (1) in a first embodiment. This lock mechanism comprises a rotary actuator (2), integral with the frame (3), electrically controlled by a polyphase switched motor, a torque motor or a proportional actuator or variable reluctance. The rotor (4) of the actuator (2) is mechanically coupled to the locking lever (5), the design of which allows the latter to disengage the passage of a third part (piston (6) in the drawing) when it has performed its rotational movement generated by the supply of the actuator (2). This lever (5) has, in association with the rotor (4) of the actuator (2) with which it is connected, a center of gravity on its axis of rotation (7). According to this embodiment, the lever (5) consists of a ferromagnetic material. The lever (5) is thus sensitive to the magnetic field generated by a polarized structure (8) (= magnetized) integral with the frame (3). The magnetic circuit is designed so that it generates a stable position of the lever at least in one position. Thus, in the absence of supply of the actuator (2), the entire rotor (4) undergoes a magnetic attraction, via the lever (5), which tends to reposition it in the vertical stable position. On other mechanisms, one can also imagine having several positions of stability (states locked and unlocked). From left to right, Figures 2a, 2b and 2c show three operating states of a locking device employing this first embodiment.

Figure 2a shows the locked state. The bolt (9) is shown in the extended position. A piston (6) of linear stroke is engaged in the bolt (9) in the high position under the action of the spring (16).

It can not go down because of the presence of the lever (5) lock. The engagement of the piston (6) in the bolt (9) is achieved through a housing (10) in the bolt (9). Thus, if a force is applied to the bolt (9), so as to translate it, it is transmitted to the piston (6) in two components. A horizontal component supported by the frame (3) and on the other hand a vertical component, lower, transmitted to the lever (5) locking. The lever being in its vertical stable position, it transmits this force to the frame, due to an elastic deformation of the axis which links it to the motor, or the support of the actuator (2). The piston (6) can not disengage the bolt (9), the lock is locked.

Figure 2b shows the lever (5) when rotated by the actuator (2) supplied with electric current. Under the action of the created torque, of greater intensity than the magneto-static torque generated by the polarized structure (8) which tends to keep it in vertical stable position, the lever (5) is pivoted.

Figure 2c shows the mechanism in the unlocked position. The bolt (9) undergoes an effort that tends to translate it. Because of the respective shapes of the piston (6) and the bolt (9), the piston (6) is driven in translation. Since the lever (5) has been pivoted, the piston (6) can continue its travel until it is completely disengaged from the bolt (9). The lock is then in an unlocked state.

Figures 3 and 4 show a second embodiment of a mechatronic locking device (1) according to the invention having an operation as described in the explanations of Figures 1, 2a, 2b and 2c. The The difference is the locking lever (5) which is designed to provide the rotor function to the actuating device as well as the magnetic interaction stability function. Thus, the lever (5) is balanced and polarized by the addition of a magnet (1 1). A stator (12) fixed to the frame (3) consists of ferromagnetic parts and is provided with a coil (13) generating a magnetic field. When feeding the coil (13), the magnetic field produced is channeled by the ferromagnetic structure of the stator (12). The interaction with the magnetic field created by the magnet (1 1) of the lever (5) generates a torque between the lever (5) and the stator (1 1), which induces the rotation of the lever (5). The assembly is designed so that the air gap between the lever (5) and the stator (1 1) varies as a function of the rotation of the lever (5). It is thus possible to achieve a minimum air gap when the lever (5) is in its stability position and maximum in the unlocked position. In doing so, when the coil (13) is no longer energized, the lever (5) undergoes a torque which tends to keep it in the stable position of minimum air gap. In Figure 4b, the device is shown in the locked position. The piston (6) is engaged in the bolt (9) and its travel is hampered by the vertical position of the locking lever (5). In this position, the air gap between the locking lever (5) and the poles (14) of the stator (12) is minimum. In the absence of power supply in the coil (13), the torque exerted without contact between the lever (5) and the stator (12) is zero in this position. The torque on the lever (5) as a function of its position and the current flowing through the coil (13) surrounding the stator (12) is shown in FIG.

In Figure 4b, the lever (5) is rotated during feeding of the coil (13). The air gap is then greater than when the lever (5) is vertical. It follows that if the current is canceled in the coil (13), it will appear a magnetostatic torque (= without current) which will cause the lever (5) to the stable position minimum gap.

Finally, in Figure 4c the device is shown in an unlocked state. The lever (5) has been rotated from its vertical position, thus releasing the piston (6) which is then likely to descend under the action of a force on the bolt (9). Figure 5 shows the couples obtained on the axis of the locking lever of an actuator as shown in the descriptions of Figures 3, 4a, 4b and 4c. The vertical stable position with the minimum air gap corresponds to the 0 ° position. Due to the air gap increase as the lever (5) is rotated, the currentless torque in the coil (13) describes the central solid curve, which is similar to a mechanical stiffness of magnetic origin. The lower - cross - and upper - squares - curves are the pairs obtained for opposite polarity currents in the coil (13). It is therefore possible to go from the locked position 0 ° to the unlocked position -30 ° by applying a current> 0 in the coil (13).

FIG. 6 shows an embodiment of the invention based on the use of a rotary solenoid type actuator as presented, for example, in patent FR2834119. This structure does not include a magnet. it can be doubled to increase the torque on the lever (5). When the coil (13) is energized, the created magnetic flux is channeled by the stator (12), stator (12) which is in two distinct parts, and loops back through the ferromagnetic locking lever (5). In doing so, there is a force of attraction between the stator (12) and the lever (5). Since the actuator (2) is not polarized, we use here a mechanical spring (15) to ensure the stability of the lever (5) in vertical position. The mechanical spring (15) is advantageously attached to the lever (5) in the vicinity of the axis of rotation, in order to damp the transmission of the shock wave when the lock (1) undergoes an external shock.

Figures 7a, 7b and 7c show in detail the three distinct states of the solution shown in Figure 6. In Figure 7a, the lever (5) is held in stable position without current by the elastic stiffness of the torsion spring. In Figure 7b, the supply of the coils (12) generates a torque on the locking lever (5) which pivots by compressing the spring (15) torsion. In Figure 7c, the lever (5) has made its entire stroke, under the action of the magnetic field generated by the stator (12). The piston (6) can then slide and release the bolt (9). Figures 8a and 8b show an embodiment of the invention as shown in Figure 6, with the difference that the mechanical spring (15) employee is of linear type (here tension spring). Figures 8a and 8b respectively show the device in the locked and unlocked state.

Claims

Locking device comprising a movable locking member (9) whose displacement can be prevented by a locking member interacting with a motorized lever (5) characterized in that said lever (5) motorized is rotatable about an axis (7) relative to the frame (3), the center of gravity of said lever (5) being located on said axis (7), said lever (5) being held in a determined stable position and without rigid mechanical contact of the lever (5). ) with the frame (3) with the exception of the connection of its axis (7) of rotation with said frame.

Locking device according to claim 1 characterized in that the stable position is achieved without power consumption.

Locking device according to claim 2 characterized in that the stable position is achieved by the action of a magnetic force acting without any mechanical contact on the lever (5).

Locking device according to claim 3 characterized in that the magnetic force maintaining the stable position of the lever (5) is also achieved by an actuator (2) moving the lever (5) locking.

Locking device according to claim 2, characterized in that the stable position is achieved by the action of at least one mechanical spring (15).

Actuator for a locking device according to claim 1, driving in rotation about a fixed axis (7) a locking lever (5) characterized in that the locking lever (5) has its center of gravity on said axis (7) fixed and in that the actuator (2) comprises at least one magnet (1 1) and has a variable gap to ensure a stable position without power consumption.

Actuator for a locking device according to claim 6 characterized in that the gap is minimum when the lever (5) is in its locked and maximum stability position in the unlocked position.