IL264236B - Locking mechanism - Google Patents

Description

LOCKING MECHANISM TECHNOLOGICAL FIELD This disclosure concerns a locking mechanism for a lock that comprise gear motor that functions to rotationally switch the lock between a locked and an unlocked state. The disclosure also concerns locks with such mechanisms.

BACKGROUND Many of modern locks include electric and electronic elements that control its operation. These include an electric motor, a control module and a battery. This electric mechanism is normally idle with the electric motor in an off, parked state. Once the mechanism is activated, e.g. by an external coded signal picked up by the control module, the electric/electronic mechanism, including the motor, is energized to assume an active state thereby unlocking the lock. For locking the lock, the control module switches the motor back to its parked state.

Electric locks are intended for operation over many years, and for this reason it is important to preserve battery life. In some types of locks, a lock operation on the basis of an operational scheme as described above requires to constantly energize the electric/electronic mechanism as long as the lock is in its unlocked state. Other types of locks suffer from quick drainage of battery due to uneven power consumption or spikes in power consumption which are caused by the mechanical set-up of the lock, e.g. instability of a gear motor that drives the locking mechanism.

GENERAL DESCRIPTION The present disclosure provides a locking mechanism operable within a lock. This disclosure also provides a lock comprising such a mechanism. Specific, non-limiting, embodiments of the lock of this disclosure are bolt locks and padlocks, examples of which are defined herein. In the locks described herein, the combination of an electrically- operated gear motor with a mechanical buffer in the locking mechanism provides for a battery-operated lock in which battery life is efficiently conserved, as will be described in details below.

Electrically-operated locks typically comprise a battery to operate the electric/electronic modules of the lock (i.e. the control module), and operates to activate the lock. Electric energy preservation is important to ensure operation of the lock for many years without the need to replace the battery.

When a lock is opened, the electric/electronic module is activated and switched from its idle state, in which it does not consume energy, to an active state in which it is electrically energized. A lock may be kept open for a long time period and if the electric/electronic mechanism is kept activated for this time period, a large amount of electric energy may be consumed and wasted, thereby reducing the battery's life. Further, as noted above, instabilities in the mechanical operation of the lock, for example fluctuations in the position of the motor, as well as blockages that prevent the mechanism from smoothly switching between its operational states, often result in large consumption of electric power. Thus, a locking mechanism that is mechanically stable at its various operational states and positions, without causing significant wear on the motor and which prevents uneven power consumptions or spikes in power consumption is also desired in order to maintain battery's life.

According to this disclosure, a locking mechanism that comprises an electrically- operated gear motor is provided, where the motor is activated to open a bolt. Comprised in this mechanism is a mechanical buffer arrangement that links a motor-associated driving element to a driven element that is associated with and operating the bolt. The buffer arrangement can store rotational mechanical energy, thereby permitting the gear motor to be stably held at a static operational state, without locking the locking mechanism. A locking sequence can then be induced at a later stage through the stored mechanical energy.

According to an embodiment of this disclosure, the buffer mechanism comprises a torsion spring, e.g. helical, one end of which being coupled to the driving element and the other end being coupled to the driven element. Through the arrangement disclosed herein, the gear motor always rotates against the biasing forces of the torsion spring, regardless of an opposite, external force that may be applied onto the bolt unit. The bias of the spring is weaker than the torsional force of the gear motor, both during rotation of the motor and when the motor is at a static state or position, thus storage of mechanical energy in the torsion spring circumvents instability in the position of the gear motor while the motor is at a static operational state, as well as reduces the wear of the gear. In other words, regardless of the forces operated on various elements of the lock, the force operated on the gear motor will only be that of the torsion spring, causing uniform consumption of electrical power. This arrangement, thus, allows conservation of battery, as no sharp spikes in power consumptions are caused.

Provided by one aspect of this disclosure is a locking mechanism that comprises an electrically-operated gear motor coupled to a driving element, a locking bolt unit with a bolt at its front end and coupled to a driven elements and a torsion spring coupling the two elements. The motor has a motor axle that is rotationally coupled to the driving element and is configured for reciprocal rotations of the driving element about an axis between a first angular position and a second angular position through respective switch between parked and operational states. The driven element can axially rotate and is configured to induce, through reciprocal rotations between a first rotational position and a second rotational position, a reciprocating linear displacement of the locking bolt unit between corresponding forward, locking position and a rearward, unlocking position. The torsion spring couples the driving element with the driven element such that rotation of said driving element into said first angular or said second angular position tensions the spring to thereby store rotational mechanical energy that biases the driven element to rotate into said first rotational position or into said second rotational position, respectively.

As noted above, the torsion spring is typically helical. The helical spring may be mounted on opposite driving and driven co-axial projections of the driving and driven elements, respectively, one end of the helical spring being fixed to the driving projection and the other end being fixed to the driven projection. The bias of the spring is typically weaker than the torsional force of the gear motor, as noted above.

The motor may be linked to an electrical/electronic control module that causes the gear motor to switch between its operational states. When the electric/electronic module is taken out if its idle state and activated it may induce the gear motor to switch to an operational state to thereby rotate the driving element from the first to the second angular position. The control module may be configured to cause the motor to switch between its states and then turn off the electric power after a defined time interval (typically a few seconds or a few tens of seconds. The activation of the control module to thereby switch the gear motor between its operational states may be achieved by an external signal, typically uniquely coded, which may be an RF signal, light signal, IR signal, acoustic signal, etc., requiring the mechanism to comprise an appropriate pick-up or sensor module coupled to or forming part of the control module.

The rotation of the driven element induces axial linear displacement of the locking bolt. By one embodiment, the bolt unit has a rotating coupling element at its rear end and the driven element is rotationally coupled to said coupling element. A helical groove or channel is defined on an external face of one of the coupling element or of a fixed element, and a guiding member is fixed to or coupled in a fixed relationship with the other, whereby rotation of said coupling element causes axial displacement of said unit.

Provide by another aspect of this disclosure is a lock that comprises a locking mechanism of the kind described and defined herein. By one embodiment the lock is a bolt lock. By another embodiment the lock is a padlock.

A bolt lock by an embodiment of this disclosure comprises a housing, an electrically-operated gear motor coupled to a driving element, a locking bolt unit coupled to a driven element and a torsion spring coupling the driving element with the driven element. The locking bolt unit extends along an axis between a front end and a rear end and has a bolt at its front end and is reciprocally displaceable along an axis between a forward, locking position, in which the bolt axially extends out of the housing and a rearward, open position in which the bolt is wholly or partially retracted into the housing.

The motor has a motor axle that is rotationally coupled to a driving element, the motor being configured to switch between a parked state to an operational state to thereby drive, respective, reciprocal rotations of the driving element about an axis between a first angular position and a second angular position. The driven element is coupled to the bolt unit and rotatable about the axis, such that upon rotation of the driven element to a first rotational position the bolt unit is displaced into its rearward position and upon the reciprocal rotation to a second rotational position the bolt unit is displaced into the forward position. The torsion spring couples the driving element with the driven element such that rotation of said driving element into said first angular position biases said driven element to rotate into the first rotational position and reciprocal rotation of the said driving element into said second angular position biases said driven element to rotate into the second rotational position.

The spring is typically helical as noted above, and may, by some embodiments of the bolt lock of this disclosure, be mounted on opposite driving and driven co-axial projections of the driving and driven elements, respectively; one end of the helical spring is fixed to the driving projection and the other end being fixed to the driven projection.

The two projections are, typically, of the same diameter. The two projections may, by some embodiments, have concentric bores accommodating a cylindrical support rod.

By some embodiments of the bolt lock of this disclosure, the bolt unit has a rotating coupling element at its rear end and the driven element is rotationally coupled thereto. A helical groove or channel is defined on an external face of one of the rotating element or of a fixed element fixed within the housing, and a guiding member is fixed to or coupled in a fixed relationship with the other, whereby rotation of said driven element causes axial displacement of said bolt unit. The coupling element may have a bore with a rear opening with the coupling member of the driven element being slidably fitted and rotationally coupled with the coupling member within said bore.

A padlock by an embodiment of this disclosure comprises a housing, a shackle with a locking-latch recess at a shackle end portion, a shackle-receiving opening for receiving and engaging the shackle end portion, a spring-biased latch for engaging the shackle end portion and an electrically-operated gear motor-based mechanism for operating the lock. The spring-biased latch is biased into a recess-engaging position and can be pushed, against the spring bias, into an opposite, recess-clearing position. A spring-biased piston is comprised within the lock that can reciprocate in a piston bore, opposite the shackle-receiving opening, against the bias of a spring, between a spring- biased latch-arresting position in which it arrests the latch in its recess-clearing position and a pressed position against the spring bias. The shackle end, once the latch is engaged with the latch recess, fits into said piston bore to thereby displace the piston into its pressed position. Operating within the lock is a locking bolt unit with a bolt at a front end thereof which can reciprocate along an axis between a forward position, in which the bolt blocks the latch in its recess-arresting position and a rearward position in which the latch is free to displace into its recess-clearing position. The bolt unit is coupled to a driven element that can rotate about the axis and is configured to induce, through reciprocal rotations between a first rotational position and a second rotational position, the reciprocating linear displacement of the locking bolt unit between corresponding forward and rearward positions. The motor has a motor axle rotationally coupled to a driving element. The motor is configured to switch between operational states to thereby drive, respective, reciprocal rotations of the driving element about an axis between a first angular position and a second angular position. A torsion spring couples the driving element with the driven element such that rotation of said driving element into said first angular or said second angular position tensions the spring to thereby bias the driven element to rotate into said first rotational position or into said second rotational position, respectively.

The torsion spring in the padlock coupling the driving and driven elements, is typically a helical spring, as noted above. The helical spring may be mounted on opposite driving and driven co-axial projections (typically of overall same diameter) of the driving and driven elements, respectively; one end of the helical spring being fixed to the driving projection and the other end being fixed to the driven projection.

By one embodiment of the padlock disposed within the housing is a cylindrical sleeve defined about an axial sleeve lumen, with the driving and driven elements and a rear end portion of the bolt unit being accommodated within the sleeve lumen. Said rear end portion has an axial bore with a rear opening accommodating a cylindrical front portion of the driven element that is coupled to the said rear end portion within the bore such that rotation of said front portion causing axial reciprocation of the bolt unit between its forward and rearward positions. Typically, the driving and the driven elements are rotationally accommodated within the sleeve lumen in a fixed axial position and rotatable in this position, said axial bore has a helical groove or channel, and a guiding member being part of or coupled in a fixed relationship with the driven element being accommodated within the groove or channel, whereby rotation of said driven element causes axial displacement of said bolt unit.

BRIEF DESCRIPTION OF THE DRAWINGS In order to better understand the subject matter that is disclosed herein and to exemplify how it may be carried out in practice, embodiments will now be described, by way of non-limiting example only, with reference to the accompanying drawings, in which: Figs. 1A-1B show schematic side-view representations of a bolt lock according to an embodiment of this disclosure, with the bolt in respective locking and unlocking positions.

Fig. 2A-2B are longitudinal cross-sections of the front portion of the lock of Figs. 1A-1B in respective locking and unlocking positions of the bolt.

Fig. 3A-3B show schematic isometric representations of a padlock according to an embodiment of this disclosure, with engaged and disengaged shackle, respectively.

Figs. 4A-4D are longitudinal cross-sections of a front end portion of the padlock of Figs. 3A-3B in four different operational states of which two, Figs. 4A-4B are with the shackle engaged within the lock and two others, Figs. 4C-4D are with the shackle removed.

DETAILED DESCRIPTION OF EMBODIMENTS In the following description the invention will be illustrated with reference to some non-limiting specific embodiments that are shown in the annexed drawings. As can be readily appreciated, these embodiments are exemplary of the much broader full scope of the disclosure provided herein.

The present disclosure provides, by one of its aspects a locking mechanism, as noted above. The locking mechanism may be provided as such for incorporating into a variety of locks, although typically it is integrally included within locks that are also an aspect of this disclosure. Two specific embodiments of such locks are described below, one being a bolt lock and the other a padlock. Both of these include the locking mechanism embodying the features of the mechanism of this disclosure. Thus, while specific embodiments of the locking mechanism are not described below in isolation, two such mechanisms are illustrated and described as part of the illustration and description of the two exemplary embodiments of a bolt lock and padlock.

Reference is now being made to Figs. 1A and 1B, showing a bolt lock 100 in two operational states: a locking state (shown in Fig. 1A) in which a bolt 102 extends out of the lock's housing 104, and an unlocked state (shown in Fig. 1B) in which the bolt is retracted into the housing. The bolt lock 100 is generally elongated and is overall cylindrically shaped defining a longitudinal axis 106, and has a rear enlarged portion 108 that houses the lock's battery (not shown). As can be appreciated, a lock with an overall cylindrical shape is but an example. In other embodiments, the external contours of the housing may be different, e.g. may have an overall prismatic shape.

Reference is now made to Figs. 2A and 2B for the purpose of illustrating the different lock elements, including the locking mechanism generally designated 110. The states of the lock in Figs. 2A and 2B correspond to those of Figs. 1A and 1B, respectively.

The mechanism 110 includes an electrically-operated gear motor 112 (of which only a front part is seen), a locking bolt unit 114 with bolt 102 at its front end, a driving element 116 coupled to the motor's axle 118, a driven element 120 coupled to a rear end 122 of the bolt unit, and a torsion spring 124 coupling the driving unit 116 and the driven unit 120 in a manner to be explained.

Driving unit 116 has an axial cavity 126, that fits over motor axle 118, and through a fastening screw 128, the driving unit becomes rotationally coupled to the motor axle.

The gear motor 112 is configured for reciprocal rotations and in this way causes reciprocal rotations of the driving element 116 about axis 106 between a first angular position seen in Fig. 2A, and a second angular position seen in Fig. 2B; in this specific embodiment, the angular displacement between these two positions is a full circle. Driving element 116 has radial extension 127 that cooperates with a sensor (not shown) for the purpose of indicating the angular position of the driving element 116 to thereby indicate if the motor 112 is in the first or in the second angular positions. An example of such a sensor arrangement can be seen in the embodiment of the padlock described below (sensor 255).

The locking bolt unit 114 with the bolt 102 at its front end can reciprocally displace along the axis 106 between the forward, locking position seen in Fig. 2A, in which the bolt axially extends out of the housing 104, and a rearward, open (unlocking) position in which the bolt is retracted into the housing, as seen in Fig. 2B.

The bolt unit's rear end member 122 is rotationally coupled to the rest of the bolt unit through fitment bridge 130 and has an internal axial lumen 132. Formed on the external face of rear end member 122 is a helical groove 134 defined within a helical abutment 136 (seen in the longitudinal cross section shown in Figs. 2A and 2B are the front end F, mid portion M and the rear end R of the groove and abutment).

The locking bolt unit 114 reciprocates within the hollow interior of a fixed element 140. Through-hole 142 is formed at a rear end of fixed element 140, and accommodates a guiding member 144, which in this specific embodiment is in the shape of a ball. As can be seen, member 144 is partially accommodated within groove 134, which in the locked state in Fig. 2A is the rear end R. Upon rotation of rear end member 122 to the counterclockwise direction about axis 106, the engagement between member 144 and groove 134 induces an linear displacement of bolt unit 114, guided by the helical groove between the locked state shown in Fig. 2A and the unlocked state shown in Fig. 2B, in which guiding member 144 engages the front end F of groove 134.

Driven element 120 is slidably coupled within lumen 132 in a manner such that rotation of driven element 120 causes also rotation of the bolt unit 114. The combination of slidability and rotational coupling can be achieved in a number of ways; such as the lumen 132 and the driven element 120 having a matching prismatic cross-section (as is the case in this embodiment). In addition such rotational coupling may be achieved by one or more radial abutments of the driven element that are fitted into a corresponding axially-extending groove in the walls of lumen 132; or a longitudinal axial abutment in the walls of lumen 132 fitting into a corresponding groove in driven element 120. It is noted however that the disclosure herein is not limited by this manner of coupling or the manner in which rotation is translated into axial displacement.

Driving element 116 and driven element 120 have co-axial opposite projections 146 and 148, respectively, with corresponding concentric bores 146A and 148A that jointly accommodate support rod 150 that is freely accommodated therein (namely, the rotation of the driving and driven elements is not coupled by the inclusion of the support rod, or in other words, each can rotate about the axis independent of the other and independent of the support rod).

Torsion spring 124 is fitted over the two projections, one end of which is coupled to the driving element 116 at location 152 and the other end to the driven element 120 at location 154. Accordingly, rotation of the driving and the driven elements is partially coupled through the torsion spring, which in this example is a helical spring, although other springs may exist in other embodiment of this disclosure. Once the driving element 116 rotates, induced to do so by the motor, a tension is built-up in spring 124 and this tension would, in turn, bias corresponding rotation of driven element 120. If there is no hindrance to rotation of the driven element, it will then rotate, causing a longitudinal displacement of the bolt unit 114 in the manner described above. The bias of the spring 124 is typically weaker than the torsional force of the gear motor, such that the tension built in the spring is insufficient to move the gear, thus maintaining the gear a stable static state although maintaining tension in the tension spring. Thus, tensioning of the spring does not cause instability in the gear motor, which typically causes undesired spikes in the energy consumption of the battery.

When the lock is activated, the motor causes rotation of driving element 116 and a consequent tension build-up in spring 124 and the consequent rotation of the driven element 120 in a clockwise direction (when viewed from the rear), and accordingly a displacement of the bolt unit from the locked state, shown in Fig. 2A, to the unlocking state shown in Fig. 2B. After a time period, the control unit of the lock (not shown) induces a counter rotation of the motor and, hence, a counterclockwise rotation of the driving element 116. As long as the bolt unit is not free to forwardly advance, e.g. blocked because of an incomplete alignment between it and a latch or kept open deliberately by another mechanism, this counter rotation is against a biasing tension build-up in spring 124. Once the displacement of the bolt unit into the locked state is permitted, the rotation of the driven element caused by the bias of the spring will advance the bolt unit into the locked state of Fig. 2A. In this manner the torsion spring 124 acts as a mechanical buffer, permitting the locking mechanism to store mechanical energy for subsequent use, while the motor is already in parked static state.

Isometric views of a padlock according to an embodiment of this disclosure are shown in Figs. 3A-3B, with Fig. 3A showing the lock with shackle engaged within the lock and Fig. 3B with the two disengaged from one another. The padlock 200 shown in Figs. 3A-3B has a lock body 202 with a housing 204, a shackle receiving opening 206 for receiving an end portion 208 of a shackle 210. As can be seen in Fig. 3B, defined in the end portion of the shackle is a locking latch recess 212.

Partial longitudinal cross-sections showing the front portion of the body and the rear portion of the shackle in four different operational states are shown in Figs. 4A-4D: Fig. 4A is a locked state in which the end portion 208 of the shackle is engaged within the shackle receiving opening 206 and a latch 214 engaged within the latch-recess 212; Fig. 4B showing an intermediate state in which latch 214 is released and prior to the moving of the shackle from the opening 206; Fig. 4C showing the lock after removal of the shackle end portion, with the latch being arrested by piston 216; and Fig. 4D showing the lock in a "ready" state, to be explained below, in which insertion of the shackle end portion will automatically induce locking through mechanical means only.

The latch 214 is biased by latch spring 218 into the position shown in Fig. 4A, and can be pushed against this spring bias into an opposite recess-clearing position shown in Fig. 4C. The latch 214 is fitted within a latch bore 220. Spring 218 is fitted about pin 222, which extends into a bore 224 defined within latch 214 through opening 226 and in its reciprocation latch 214 moves also relative to pin 222, which also, through this arrangement, guides the reciprocation of the latch.

Piston 216, seen in a pressed position in Fig. 4A, is coupled to a piston spring 228, which biases the piston into a latch-arresting position, as can be seen in Fig. 4C, and can assume this position upon removal of the shackle end portion. In the position shown in Fig. 4A, the piston is kept in the depressed position by the end of the shackle. Piston 216 is formed at an end of a rod 230, that passes through opening 232 into a sensing box 234, its end pressing on spring-biased plunger 236 that is coupled to sensors (not shown) that provide an indication of the overall state of the lock, namely whether it is open or locked.

The forward displacement of piston 216 is limited by washer 238, such that in its most forward position, seen in Figs. 4C-4D, the piston arrests the latch 214 in the recess- clearing position.

The lock also includes a locking mechanism generally designated 240, that includes a lock bolt unit 242, with a bolt 244 at its front end. The bolt 244 passes through an opening 246 into latch bore 220, and when in the forward position seen in Fig. 4A, blocks the latch in the latch's recess-engaging position. The locking mechanism also includes electrically-operated gear motor 250, driving an axel 252 through gear 254. The axel 252 is rotationally coupled through a coupler 256 to the driving element 258. Coupler 256 has radially extending disc 257 that is formed with slits 259. Disc 257 rotates within a sensing space 253 of sensor 255 that comprises a light source at one side of the sensor 255 and a sensing element at the other, opposite one another along a sensing line. Once one of the slits 259 is aligned with the sensing line, light is transmitted through the slit and detected by the sensor, and hence a driving element position is established. In case there is more than one slit 259, the angular separation between them is such to define extreme angular positions of the driving element 258 to cause full linear reciprocation of the bolt 244, as described below. For example, there may be two slits at 90º or 180º to one another; or there may be one slit 259, in which case the driving element moves a full circle between its two extreme angular positions.

Driving element 258 is coupled through a torsion spring 260 to a driven element 262. Motor 250 can rotationally reciprocate the coupler 256 and the driving element 258 about axis 264 between a first angular position shown in Fig. 4A and a second angular position shown in Fig. 4B, which are in this embodiment are angularly separate one from the other by half a circle.

Torsion spring 260, which is this example is a helical spring, is coupled at each of its ends to one of the driving element 258 and the driven element 262, the coupling being at location 266 and location 268, respectively. In a similar manner to that described above in connection with the bolt lock, the rotation of the driving element 258 causes tension in spring 260, which consequently if the driven element is free to rotate – induces its rotation; if not, a tension is built in the spring storing mechanical rotational energy for subsequent rotation of the driven element. As in the case of the bolt lock, spring 260 is typically weaker than the torsional force of the gear motor 250.

The driving and driven elements 258 and 262 are accommodated within the lumen 270 of an axial sleeve 272 together with the rear end portion 274 of the bolt unit 242. The rear end portion 274 has an axial bore 276 with a rear opening that accommodates a cylindrical front end portion 278 of the driven element 262. The axial bore 276 has a helical groove 280. A guiding member 282 in the form of a ball is accommodated in a space defined between an opening 284 of sleeve 272 and the helical groove 280. The coupling between the driven element 262 and the axial bore 276 such that the former's rotation also rotates the later, and such rotation, guided by helical groove 280 causes linear reciprocation of bolt unit 242. Thus, when once then driving element 258 is rotated through the action of motor 250 in a counterclockwise direction (when viewed from the rear end) it causes rearward linear displacement along axis 264 of the bolt unit to the position shown in Fig. 4B. In this position, latch 214 is free to move within its bore and once the shackle 210 is twisted, the latch 214 is pushed upward (in the direction seen in Fig. 4A), and when the shackle is removed from opening 206 – piston 216 can move into the position shown in Fig. 4C arresting the latch 214 in its latch recess-releasing state.

Then the control unit induces reciprocal rotation of the motor, and hence rotation of driving element 258 into its original position, as shown in Fig. 4D. This causes tension build-up in torsion spring 260 which stores rotational mechanical energy. Once the shackle is pushed back into opening 206, piston 216 is pushed back to its pressed position and the latch 214 can move back to engage the latch recess by the bias of latch spring 218 and once in this position, the bolt can move back to its original position by the rotational bias of torsion spring 260 to the original position of Fig. 4A.

Claims (18)

CLAIMED IS:

1. A locking mechanism, comprising: an electrically-operated gear motor with a motor axle rotationally coupled to a driving element, the motor being configured for reciprocal rotations of the driving element about an axis between a first angular position and a second angular position; a locking bolt unit with a bolt at its front end; a driven element that can axially rotate and is configured to induce, through reciprocal rotations between a first rotational position and a second rotational position, a reciprocating linear displacement of the locking bolt unit between corresponding forward, locking position and a rearward, unlocking position; and a torsion helical spring coupling the driving element with the driven element such that rotation of said driving element into said first angular or said second angular position tensions the spring to thereby bias the driven element to rotate into said first rotational position or into said second rotational position, respectively, the torsion helical spring being mounted on opposite driving and driven co-axial projections of the driving and driven elements, respectively, one end of the helical spring being fixed to the driving projection and the other end being fixed to the driven projections, the bias of the torsion spring is weaker than the torsional force of the gear motor.

2. The locking mechanism of claim 1, wherein the motor is linked to a control module that causes the motor to switch between operational states to thereby rotate said driving element between the first to the second angular position, respectively, and the gear motor can be stably held in an operational state while switched off of electric power.

3. The locking mechanism of claim 2, wherein the control module is configured to cause the motor to switch between operational states at defined time intervals and turn off the electric power.

4. The locking mechanism of any one of the preceding claims, wherein rotation of the driven element induces axial linear displacement of the locking bolt.

5. The locking mechanism of claim 4, wherein the bolt unit has a rotating coupling element at its rear end; the driven element is rotationally coupled to said coupling element; and 14 264236/2 a helical groove or channel is defined on an external face of one of the coupling element or of a fixed element, and a guiding member is fixed to or coupled in a fixed relationship with the other, whereby rotation of said coupling element causes axial displacement of said unit.

6. A lock comprising a locking mechanism of any one of the preceding claims.

7. A bolt lock, comprising: a housing; a locking bolt unit extending along an axis between a front end and a rear end and having a bolt at its front end, the bolt unit being reciprocally displaceable along an axis between a forward, locking position, in which the bolt axially extends out of the housing and a rearward, open position in which the bolt is wholly or partially retracted into the housing; an electrically-operated gear motor with a motor axel rotationally coupled to a driving element, the motor being configured for reciprocal rotations of the driving element about an axis between a first angular position and a second angular position; a driven element coupled to the bolt unit and rotatable about the axis, such that upon rotation of the driven element to a first rotational position the bolt unit is displaced into its rearward position and upon the reciprocal rotation to a second rotational position the bolt unit is displaceable into the forward position; and a torsion helical spring coupling the driving element with the driven element such that rotation of said driving element into said first angular position biases said driven element to rotate into the first rotational position and reciprocal rotation of said driving element into said second angular position biases said driven element to rotate into the second rotational position, respectively, the torsion helical spring being mounted on opposite driving and driven co-axial projections of the driving and driven elements, respectively, one end of the helical spring being fixed to the driving projection and the other end being fixed to the driven projections, the bias of the torsion spring is weaker than the torsional force of the gear motor.

8. The bolt lock of claim 7, wherein the motor is linked to a control module that causes the motor to switch between operational states to thereby rotate said driving element between the first to the second angular position, respectively, and the gear motor can be stably held in an operational state while switched off of electric power. 15 264236/2

9. The bolt lock of claim 8, wherein the control module is configured to cause the motor to switch between operational states at defined time intervals and turn off the electric power.

10. The bolt lock of any one of claims 7 to 9, wherein the two projections have the same diameter.

11. The bolt lock of any one of claims 7 to 10, wherein the two projections have concentric bores accommodating a cylindrical support rod.

12. The bolt lock of any one of claims 7 to 11, wherein the bolt unit has a rotating coupling element at its rear end; the driven element is rotationally coupled to said coupling element; and a helical groove or channel is defined on an external face of one of the rotating element or of a fixed element fixed within the housing, and a guiding member is fixed to or coupled in a fixed relationship with the other, whereby rotation of said driven element causes axial displacement of said bolt unit.

13. The bolt lock of claim 12, wherein said coupling element has a bore with a rear opening; a coupling member of the driven element is slidably fitted and rotationally coupled with the coupling member within the bore.

14. A padlock, comprising: a housing; a shackle with a locking-latch recess at a shackle end portion; a shackle-receiving opening for receiving and engaging the shackle end portion; a spring-biased latch that is biased into a recess-engaging position and can be pushed, against the spring bias, into an opposite, recess-clearing position; a spring-biased piston reciprocating in a piston bore opposite the shackle-receiving opening against the bias of a spring, between a spring-biased latch-arresting position in which it arrests the latch in its recess-clearing position and a pressed position against the spring bias; the shackle end, once the latch is engaged with the latch recess, fits into said piston bore to thereby displace the piston into its pressed position; 16 264236/2 a locking bolt unit with a bolt at a front end thereof which can reciprocate along an axis between a forward position, in which the bolt blocks the latch in its recess-arresting position and a rearward position in which the latch is free to displace into its recess-clearing position; a driven element that can rotate about the axis and is configured to induce, through reciprocal rotations between a first rotational position and a second rotational position, the reciprocating linear displacement of the locking bolt unit between corresponding forward and rearward positions; an electrically-operated gear motor with a motor axle rotationally coupled to a driving element, the motor being configured for reciprocal rotations of the driving element about an axis between a first angular position and a second angular positions; and a torsion helical spring coupling the driving element with the driven element such that rotation of said driving element into said first angular or said second angular position tensions the spring to thereby bias the driven element to rotate into said first rotational position or into said second rotational position, respectively, the torsion helical spring is mounted on opposite driving and driven co-axial projections of the driving and driven elements, respectively, one end of the helical spring being fixed to the driving projection and the other end being fixed to the driven projection, the bias of the torsion spring is weaker than the torsional force of the gear motor.

15. The padlock of claim 14, wherein, the motor is linked to a control module that causes the motor to switch between operational states to thereby rotate said driving element between the first and the second angular position, respectively, and the gear motor can be stably held in an operational state while switched off of electric power.

16. The padlock of claim 15, wherein the control module is configured to cause the motor to switch between operational states at defined time intervals and turn off the electric power.

17. The padlock of any one of claims 14 to 16, comprising: a cylinder sleeve defined about an axial sleeve lumen; the driving and driven elements and a rear end portion of the bolt unit being accommodated within the sleeve lumen; and 17 264236/2 said rear end portion having an axial bore with a rear opening accommodating a cylindrical front portion of the driven element, said front portion being coupled to said rear end portion within the bore such that rotation of said front portion causing axial reciprocation of the bolt unit between its forward and rearward positions.

18. The padlock of claim 17, wherein the driving and the driven elements are rotationally accommodated within the sleeve lumen in a fixed axial position, said axial bore has a helical groove or channel, and a guiding member being part of or coupled in a fixed relationship with the driven element being accommodated within the groove or channel, whereby rotation of said driven element causes axial displacement of said bolt unit.