US3835679A

US3835679A - Time control safety lock for a safe or the like with indicating means outside the safe for indicating the time control of the lock

Info

Publication number: US3835679A
Authority: US
Inventors: A Heinemann; W Opferkuch
Original assignee: KROMER T KG
Current assignee: KROMER T KG
Priority date: 1971-10-20
Filing date: 1972-10-18
Publication date: 1974-09-17
Anticipated expiration: 1991-09-17
Also published as: DE2152221A1; GB1369320A; NL7214288A

Abstract

Time control safety lock for a safe or the like in which a blocking member is withdrawn by a clockwork mechanism during a predetermined time period out of the path of a locking member to permit opening of the safe only after elapse of said predetermined time period, and in which signalling means observable at a location outside the safe are provided to indicate the presence of the time controlled blocking member and preferably also the time period this blocking member will still remain in blocking position.

Description

United States Patent [1 1 Heinemann et al.

[451 Sept. 17, 1974 1 TIME CONTROL SAFETY LOCK FOR A SAFE OR THE LIKE WITH INDICATING MEANS OUTSIDE THE SAFE FOR INDICATING THE TIME CONTROL OF THE LOCK [75] Inventors: Albert Heinemann, Scherzingen;

Wilhelm Opferkuch, Freiburg, both of Germany [73] Assignee: Theodore Kromer KG, Freiburg/Br.,

Germany [22] Filed: Oct. 18, 1972 [21] Appl. No.: 298,786

[30] Foreign Application Priority Data Oct, 20, 1971 Germany 2152221 [52] US. Cl 70/271, 70/273, 70/432 [51] Int. Cl E051) 43/00 [58] Field of Search 70/267, 268, 269, 270,

70/271, 272, 273, 266, 432; 116/2, 4, 6; 340/282, 177 VA; 58/152 H 5 6] References Cited UNITED STATES PATENTS 665,374 1/1901 Stockwell 70/273 717,477 12/1902 Walther 340/282 X 925,900 6/1909 Hansen l 70/267 X 1,164,378 12/1915 Miller 70/270 X 2,561,512 7/1951 Holmes et a1. 235/92 DN UX 2,772,411 10/1966 Cooper 340/282 3,227,863 1/1966 Winsor 340/282 UX 3,509,527 4/1970 Oukcs ct a1. 340/282 X 3,643,420 2/1972 Haydon 1. 58/25 X Primary Examiner-Robert L. Wolfe Assistant Examiner-Richard P. Tremblay Attorney, Agent, or Firm-Michael S. Striker 5 7 ABSTRACT Time control safety lock for a safe or the like in which a blocking member is withdrawn by a clockwork mechanism during a predetermined time period out of the path of a locking member to permit opening of the safe only after elapse of said predetermined time period, and in which signalling means observable at a location outside the safe are provided to indicate the presence of the time controlled blocking member and preferably also the time period this blocking member will still remain in blocking position.

13 Claims, 8 Drawing Figures PAIENIEBSEPITBH 3.835.619

SHEET 1 0F 6 FIG] PATENIL SEPI 11974 SHEEI 2 B 6 mdE 9.3 mm, 0? 1m 74: ET 5rd 3 v NOE PAIENIED m" 1835.679

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sum

3 or 6 FIG. 4

PATENTEDSEP 1 mm SHEEI 5 0F 6 FIGJS TIME CONTROL SAFETY LOCK FOR A SAFE OR THE LIKE WITH INDICATING MEANS OUTSIDE THE SAFE FOR INDICATING THE TIME CONTROL OF THE LOCK BACKGROUND OF THE INVENTION This invention relates to a time-controlled safety lock containing at least one clockwork mechanism for withdrawing a blocking member or for unblocking the path of a locking or like element at a preselectable time.

Time-controlled safety locks for securing the doors of steel safes, bank strong rooms and the like are well known in the art. Generally such time-controlled locks contain at least two or more clockwork mechanisms of which only one is actually needed for controlling a blocking mechanism, whereas the others are merely duplicates which are available in the event of failure of one of the clockwork mechanisms. These timecontrolled locks are affixed to the inside of the door they secure and they cannot be seen or operated from the outside when the door is closed.

In the case of doors secured by conventional locks of this type it is therefore impossible by external inspection to establish the presence of a time-controlled lock for blocking the door until the expiry of a preset period. This has the drawback that in the event of a raid the only way a person holding the keys can demonstrate the presence of a time-controlled lock is to open the main locks and to show the burglars that this fails to open the locking mechanism of the door. If the person attempting the robbery is not convinced by this evidence the threatened person holding the keys may be in considerable danger.

SUMMARY OF THE INVENTION For this reason it is the object of the present invention to provide a time-controlled lock of the abovespecified kind which eliminates the above-described risk.

To attain this object the present invention provides a time-controlled lock of the specified kind which in a visible position on the outside of the door secured by such a lock comprises an optical and/or acoustic indicating device associated with the clockwork mechanism or mechanisms of the time-controlled lock, or directly or indirectly driven thereby, for disclosing the presence and the blocking of the lock and for indicating at least the final part of the time remaining to the unblocking of the lock. This arrangement enables a would-be burglar to see for himself that the door is secured by a time-controlled lock that cannot be interfered with from the outside until the indicated time has elapsed. This is more likely to persuade him to abandon the raid.

It may be useful to provide a blocking member which during the lapse of a preset blocking time is slowly withdrawable by the one or more clockwork mechanisms into an'unblocking position in which it permits a locking element, bolt or the like associated with the locking mechanism of the lock to be withdrawn, and which cooperates with setting means of a measuring potentiometer incorporated in the electrical circuit of an indicating instrument, preferably in the form of an ammeter. This simple arrangement permits the passage of time to be represented by the change in current due to the change in potentiometer setting and to be indicated by the ammeter. The scale of the measuring instrument may be calibrated in units of time, preferably in hours. In a preferred embodiment the blocking member may have an extension in the form of a rack which meshes with the setting pinion of the measuring potentiometer. In a modified form of construction a shift bar cooperates with the clockwork mechanisms and is provided along part of its length or in the form of an extension with a rack for driving the setting pinion of a measuring potentiometer in the energizing circuit of an indicating instrument. In these embodiments only that part of the blocking time is actually indicated, during which the clockwork mechanisms are in engagement with the shift bar. This part may comprise the final ten hours of the total blocking time which may be up to hours. Any one of these embodiments will therefore either indicate to a would-be burglar that more than 10 hours must still elapse before the lock is unblocked or, if this time is less than ten hours, the instrument will indicate the time that remains before the lock is unblocked.

In yet another arrangement the output shaft of at least one of the clockwork mechanisms may be directly or indirectly coupled for instance by means of the gearwheel under the clock dial with a measuring potentiometer or the like incorporated in the electrical circuit of an ammeter or similar indicating instrument. In such an arrangement the entire time lock will continue to be blocked at any particular moment can be shown. Moreover, this latter arrangement affords the possibility of re-checking the selected blocking time when the timecontrolled lock has been set.

In an alternative arrangement the blocking member is provided with a sliding contact or associated with a rotary multi-position contact for cooperation with a plurality of fixed contacts for consecutively closing circuits through a plurality of associated signal lamps or the like which are thus made to light up in succession for indicating the passage of time to the end of the blocking period. The width of the sliding surface on the moving contact may be sufficient to enable it to complete the circuits of two neighboring signal lamps at the same time when it is in an intermediate position between two consecutive fixed contacts, two neighboring lamps glowing simultaneously indicating an intermediate time. For example, if each signal lamp lights up at the full hour, the lighting up of two neighboring lamps simultaneously would indicate the half hour. In another modification the several contacts may be connected to a difference counter preferably capable of counting forwardly and rearwardly. For instance, this difference counter could be adjusted to the full hours when the blocking time is being preset, the counter then counting down the hours to zero. For counting only the last part of the blocking-times a relatively simple counter could be used showing one digit only.

Instead of an optical indicating means, or in addition thereto, at least one microphone may be provided adjacent the clockwork mechanism and connected to a loudspeaker outside the safe to transmit the noise of the clockwork mechanism to the outside. Any wouldbe burglar may well be impressed and convinced of the presence of a time-controlled safety lock if he can actually hear the clocks ticking.

In order to use the batteries for running these indicating devices as sparingly as possible it is desirable to provide the electrically operated indicating instrument with a switch so that the instrument will work only when it has been turned on by the switch. This means that the indicating instruments need not operate during the greater part of the period the lock remains blocked, and that the batteries will not be used during this part of the period. For a check at any time the switch can be operated and the instrument read.

Moreover, in a preferred arrangement the electrical circuits for an optical and/or acoustic indication of the running down of the clockwork mechanisms, which could incidentally be electrical clockwork mechanisms, may be optionally connectableto the mains or to batteries in such a way that a relay brings in the battery supply when the mains supply is cut off. Such an arrangement prevents failure of the lock as a result of failure of the power supply, even if normally the lock relies on the mains, and it is thus possible to make use of electrically driven clockwork mechanisms.

In time-controlled safety locks containing withdrawable blocking members only a minor fraction of the blocking member projects, during the last part of the blocking period, into the path of the element the blocking member is intended to block. This may permit the lock to be opened by using some force before the blocking period has completely expired. It is, therefore, an incidental object of the present invention so to construct the time-controlled lock and the associated indicating means that the above-described risk is eliminated.

This development of the invention, which is considered to possess particular merit, consists in that the withdrawal of the blocking member in opening direc tion proceeds at a uniform rate until shortly before the blocking time is due to expire and then at a higher rate to the end of the blocking period.

If the blocking member is arranged to be withdrawn at a higher rate during the final hour of the blocking period, then the available distance for the withdrawal of the blocking member during this final hour has to be correspondingly longer. Accordingly the distance traversed even during a final half hour has to exceed the distance traversed by the blocking member in the same period if its rate of withdrawal had remained unchanged. The blocking member will therefore also project a longer distance into the blocked path than when its rate of withdrawal is uniform.

Such differences in the rate of withdrawal of the blocking member can be generated with the aid of a uniformly running clockwork mechanism by the interposition of suitable transmission means. A suitable embodiment of such a mechanism is one in which the displacement of a shift rod effected by the clockwork mechanisms is used to deflect at least one swing arm, a further transmission arm fast on the pivot pin to which the swing arm is affixed being coupled by a slot and pin coupling to a third lever arm adapted to withdraw the blocking member, the slot being provided on one arm and the pin on the other arm, and the slot having a curvature which with due regard to the lever motions and lever ratios imparts a uniform rate of displacement to the blocking member during the major part of its withdrawal, whereas the slot contains an abrupt change in its angle of inclination adapted to impart an accelerated rate of displacement to the blocking member during the latter part of its motion, with the operation of the indicating instrument at a correspondingly higher rate. The total path length of the withdrawing blocking member need not be longer than in a lock lacking the two-rate withdrawal feature. The path length provided up to the beginning of the final period can be slighly reduced to make a longer path available for the final period before the unblocking of the lock, this longer path being traversed accordingly at a higher rate.

Accordingly the scale indicating the final period may also be lengthened or the number of lamps indicating this final period may be increased, thereby providing a finer subdivision of the time scale in this region.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the folling description of specific embodiments when read in connection with the accompanying drawings.

- BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a general view of a time-controlled safety lock according to the invention;

FIG. 2 is a section on the line IIII of FIG. 1;

FIG. 3 is a cross section normal to the section shown in FIG. 2;

FIG. 4 is a schematic representation showing the association of a blocking member in the time-controlled lock with a measuring potentiometer, and the method of transmitting the potentiometer signal to an indicating instrument; v

FIG. 5 is a modified form of construction in which a sliding contact is connected to the blocking member;

FIG. 6 is a section of the indicating instrument associated with the embodiment comprising a sliding contact and a number. of signal lamps;

FIG. 7 is a view of the indicating instrument in FIG. 6; and

FIG. 8 is awiring diagram of the indicating instrument shown in FIGS. 5 to 7.

DESCRIPTION OF THE PREFERRED EMBODIMENTS With reference to FIG. 1 a time-controlled lock generally indicated by reference number 1 contains three mechanical clockwork mechanisms 3 in a casing 2, two of said clockwork mechanisms being merely provided as a precaution against the possibility of failure of one of the clockwork mechanisms.

In a manner which as such is known in the art these clockwork mechanisms 3 have clockwork driven dials 4 which perform a complete revolution within a specific period of time. Embodiments which have proved useful have dials which revolve once in hours, and which thus permit a sequence of consecutive nonworking days to be bridged. These dials can be preset to a desired period of time, the setting operation simultaneously winding the clockwork mechanism for this period.

In a conventional manner the rotating dials 4 carry pins 5 or the like which at the end of a given period of time each engage a tooth 6 on a shift bar 7.

From the time of engagement onwards and for the remainder of the preset time the shift bar 7 will therefore move. The shift bar 7 transfers its movement, in a manner as will be described later, to a blocking member 8 which is thereby gradually withdrawn from an opening 9 into which a pin 10 connected to the mechanism of the main locking system must be received for unlocking the door. Since the pin 10 cannot fully enter this opening 9 until the blocking member 8 has been completely withdrawn in the direction indicated by an arrow Pf 1, the time-controlled lock remains locked and cannot be unlocked until the preset blocking time has elapsed.

The proposal made by the invention consists in externally clearly disclosing the presence of the timing device by indicating at least that part of the time during which the blocking member is being withdrawn.

In the embodiment according to FIG. 4 the blocking member 8 carries a rack 1 1 which extends in the direction of withdrawal of the blocking member, and which meshes with a pinion 12 mounted on the setting shaft 13 of a potentiometer 14. This potentiometer is included in the electrical circuit of an ammeter 15 and the current flowing in this circuit will therefore gradually vary as the setting shaft of the potentiometer 14 turns. The scale 16 of the ammeter 15 may be graduated in hours to permit at least the last part of the period the lock continues to be blocked to be read. The pointer 17 of the ammeter 15 may give the reading at the extreme end 16a of the scale 16 before the shift bar 7 begins to withdraw the blocking member 8, thus indicating that the lock cannot be unlocked for a period exceeding say 10 hours.

It will also be understood from FIG. 4 that the final hour occupies a portion of the scale 16 which is about twice as long as that of the other hours. It will be later described how a correspondingly more rapid withdrawal of the blocking member by a longer distance in the final period is effected.

A different embodiment is illustrated in FIGS. 5 to 8. In this example the blocking member 8 carries a sliding contact 18 which in course of the withdrawal of the blocking member in the direction of arrow Pf 1 consecutively rides over a sequence of fixed contacts 19 and thereby consecutively closes the electrical circuits of signal lamps 20, as schematically illustrated in detail in FIG. 8. The current source is presumed to be a battery 21. The several signal lamps in FIGS. 7 and 8 may be arranged to indicate the last ten hours of the period the time-controlled lock remains blocked.

FIG. 8 shows a switch 22 in the main circuit of these signal lamps 20 which, as a rule, is kept open. The circuit of the battery 21 is then ordinarily without current, energy of the battery 21 is saved and none of the signal lamps is operating. At the moment the switch 22 is closed, however, it reveals the presence of a timecontrolled lock and also indicates as to when the locking time will expire. In this embodiment there is provided according to FIGS. 6 and 7 a central press button 23 for actuating the switch 22, said press button closing the switch 22 when being depressed, e.g., against the force exerted by a spring, and opening said switch when being released.

In a similar manner the embodiment according to FIG. 4 may comprise, too, a switch for closing the circuit of the ammeter 15 so that also in this arrangement the batteries provided as energy sources are not used. Moreover, the embodiment according to FIG. 4 may comprise as an additional indicating element a signal lamp 24 which indicates that the time controlled lock is still blocked.

In the embodiment according to FIGS. 5 to 8 an additional signal lamp may be provided to indicate the time preceding the last 10 hours of the preset blocking period.

In a different form of construction, not shown in the drawings, it would be feasible for instance directly to couple the rotating dial 4 of one of the clockwork mechanisms 3 with a measuring potentiometer of the like, and the passage of time could then be indicated on a scale in much the same way as in FIG. 4. The provision of mechanical transmission means from the clockwork mechanisms 3 to an indicating instrument provided with a calibrated scale would also be possible. However, a transmission through electrical circuits has the major advantage that no conclusions can be drawn from the position of the indicating instrument where the time-controlled lock is in fact situated in the closed door. Also, electrical transmission is simpler.

As already mentioned in the description of the illustrated embodiments it is proposed to move the blocking member more rapidly during the final stage of its withdrawal so that it travels a longer distance during this time. This is indicated by the lengthening of the scale 16 in FIG. 4 and by the provision of a larger number of signal lamps 20 for indicating the last hour of the blocking period in the embodiment according to FIGS. 7 and 8. The object of this arrangement is to ensure that the blocking member 8 will still project sufficiently far into the opening 9 to prevent the pin 10 from entering at a time immediately preceding the preset end of the blocking period. If the rate of withdrawal of the blocking member 8 were uniform, the pin 10 could be forced into the opening shortly before the end of the blocking period, since the blocking member 8 would at this time project very little in the path of the locking member 10. The increased rate of withdrawal substantially eliminates such a possibility. A time-controlled lock thus designed is therefore very much safer and a would-be safebreaker may as well be warned that the time for opening the safety lock is approaching.

It will be understood, principally by reference to FIG. 1, how a differential rate of withdrawal of the blocking member 8 is achieved despite the uniform speed of the clockwork mechanisms 3.

The shift bar 7 in this arrangement operates two

swing arms

25 and 26. An additional transmission arm 28 is fast on the pivot pin 27 to which the arm 26 is affixed. The transmission arm 28 is coupled by a pin and slot coupling in a manner yet to be described to a lever arm 29 which engages the blocking member for displacing the same. The slot 30 is provided on one of the arms and the cooperating pin 31 on the other. In the described embodiment the slot 30 is formed in a widened part of the transmission arm 28, whereas the cooperating pin 31 is fitted to the lever arm 29. When the transmission arm 28 is deflected in the direction indicated by an arrow Pf 2, the lever arm 29 is forced to swing in the direction indicated by an arrow Pf 3 by virtue of the curvature of the slot 30. The slot thus brings about the withdrawal of the blocking member 8 in the direction of arrow Pf 1 since the free rounded end 29a of the lever arm 29 is received intoa corresponding socket 32 in the blocking member 8. The portion of the slot 30 along which the pin 31 initially slides has a curvature which with due regard to the lever ratios causes a substantially uniform displacement of the blocking member during the greater portion of its time of with drawal. However, in the final part of the withdrawing motion the slot 30 is abruptly off-angled at 33 and this part of the slot causes the pin 31 to be far more quickly displaced than before, although the angular speed of the transmission arm 28 is unchanged. The slightly more inclined portion of the slot 30 for the reception of the pin after the latter has passed through the offangled portion at 33 merely serves for the accommodation of the overrun of the clockwork mechanisms after the end of the blocking period.

It will be seen by referring to FIG. 1 that the slot 30 is located between the fulcrum 34 of the lever arm 29 and its point of engagement with the blocking member 8 and that from its beginning at 30a, where the pin is situated at the start of the period of withdrawal, the slot slightly reduces its radial distance from the boss 35 of the transmission arm 28 on the pivot pin 27, towards which the blocking member is withdrawable. It is also apparent that the off-angled portion at 33 in the slot offsets the slot towards the boss of the transmission arm. The desired effect is thus achieved with a minimum of mechanical means, the blocking member being withdrawn at a slow uniform rate during the major portion of its motion and then at a much more rapid rate during the final hour or some other part of the blocking period.

In the embodiment according to FIG. 4 the rate of withdrawal of the blocking member during the final part of the blocking period is twice that during the preceding period of displacement. In the embodiment according to FIG. 7 an even higher rate of displacement during the final part of the blocking period is provided.

In a desirable manner this additional safety feature of the time-controlled lock can also be recognized by an intruder who may thus be persuaded that an attempt on the lock shortly before the end of its blocking time would also be fruitless.

FIG. 1 also shows gearwheels 4a below the rotating setting dials 4 and that these gearwheels are adjustable by pinions 4b and which they are in mesh for simultaneously presetting and winding the clockworks.

lt will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of time controlled safety locks differing from the types described above.

While the invention has been illustrated and described as embodied in a time controlled safety lock with indicating means indicating the time the lock remains blocked, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims:

1. A time controlled safety lock comprising a locking member for locking the door of a safe or the like and adapted to be withdrawn along a predetermined path for permitting opening of the door; a blocking member movable between a blocking position located in the path of said locking member to prevent withdrawal of the latter and an unblocking position completely withdrawn out of said path; at least one clockwork mechanism cooperating with said blocking member for moving the latter within a predetermined time from said blocking to said unblocking position; and indicating means cooperating with said clockwork mechanism for disclosing at a location outside the door the time controlled blocking of the lock and also the final part of the time said blocking member will remain in said blocking position, said indicating means including an electrical instrument and a measuring potentiometer in circuit with said electrical instrument and having setting means, and coupling means for coupling said setting means of said potentiometer with said blocking means for movement therewith.

2. A time controlled safety lock as defined in claim 1, wherein said electrical instrument is an ammeter.

3. A time controlled safety lock as defined in claim 1, wherein said indicating instrument has a graduated scale calibrated in units of time, such as hours.

4. A time controlled safety lock as defined in claim 1, wherein said coupling means comprise a rack fixed to said blocking member for movement therewith and a pinion meshing with said rack and cooperating with said setting means of said potentiometer.

5. A time controlled safety lock as defined in claim 1, wherein said coupling means comprise a shift bar moved in substantially longitudinal direction by said clockwork mechanism and provided along part of its length with a rack and a pinion meshing with said rack and cooperating with said setting mechanism of said potentiometer.

6. A time controlled safety lock comprising a locking member for locking the door of a safe or the like and adapted to be withdrawn along a predetermined path for permitting opening of the door; a blocking member movable between a blocking position located in the path of said locking member to prevent withdrawal of the latter and an unblocking position completely withdrawn out of said path; at least one clockwork mechanism cooperating with said blocking member for moving the latter within a predetermined time from said blocking to said unblocking positions; transmission means between said clockwork mechanism and said blocking member for moving said blocking member during a first part of said predetermined time period at a uniform rate towards said unblocking position and then at a higher rate during the remaining part of said predetermined time period; and indicating means cooperating with said blocking member for disclosing at I a location outside the door the time controlled blocking of the lock.

7. A time controlled safety lock as defined in claim 6, wherein said transmission means comprises a shift bar operatively connected to said clockwork mechanism to be moved thereby substantially in longitudinal direction, a swing member pivotably connected at one end to said shift bar and fixed at the other end to a pivot pin, a transmission arm fixed at one end to said pivot pin, a lever arm pivoted at one end and operatively connected at the other end to said blocking member, and a pin and slot connection between said arms and comprising a slot in one of said arms and a pin fixed to the other arm and extending through said slot, said slot having a first portion of a curvature so as to impart a uniform rate of withdrawal to said locking member during a major part of said predetermined time period and a second portion abruptly deviating from the curvature of said first portion to impart an accelerated rate of withdrawal to said blocking member during the latter part of its motion, which thus operates said indicating means at a corresponding higher rate.

8. A time controlled safety lock as defined in claim 7, wherein said pin and slot connection is located between said one and the other end of said lever arm, wherein said blocking member has one end which in said blocking position is spaced further from said pivot pin then in said unblocking position and wherein said second portion of said slot is curved further in the direction towards said pivot pin than said first slot portion.

9. A time controlled safety lock as defined in claim 6, wherein said indicating means comprises an indicating instrument having a pointer moved in correspondence with the movement of said locking member and a scale cooperating with said pointer, said scale being lengthened at the last part thereof in correspondence with the accelerated rate of withdrawal of said locking member.

10. A time controlled safety lock as defined in claim 6, wherein said indicating means comprises a series of equally spaced signal lamps and contact means cooperating with said blocking member for energizing said signal lamps in succession in dependence of position of said blocking member, and an indicia at each of said signal lamps indicating respectively the time the lock will remain blocked, the indicia of the last few signal lamps indicating shorter time periods than the preceding lamps of said series of equally spaced lamps.

11. A time controlled safety lock comprising a locking member for locking the door of a safe or the like and adapted to be withdrawn along a predetermined path of permitting opening of the door; a blocking member movable between a blocking position located in the path of said locking member to prevent withdrawal of the latter and an unblocking position completely withdrawn out of said path; at least one clockwork mechanism cooperating with said blocking member for moving the latter within a predetermined time from said blocking to said unblocking position; and indicating means cooperating with said clockwork mechanism for disclosing at a location outside the door the time controlled blocking of the lock, said indicating means including a plurality of signal lamps and including contact means cooperating with said blocking member for energizing said signal lamps in succession in dependence on the position of said blocking member.

12. A time controlled safety lock as defined in claim 11, wherein said contact means comprise a sliding contact connected to said blocking member for movement therewith and a plurality of spaced stationary contacts respectively in circuit with said signal lamps.

13. A time controlled safety lock comprising a locking member for locking the door of a safe or the like and adapted to be withdrawn along a predetermined path for permitting opening of the door; a blocking member movable between a blocking position located in the path of said locking member to prevent with drawal of the latter and an unblocking position completely withdrawn out of said path; at least one clockwork mechanism cooperating with said blocking member for moving the latter within a predetermined time from said blocking to said unblocking position; and indicating means cooperating with said clockwork mechanism for disclosing at a location outside the door the time controlled blocking of the lock, said indicating means including an electrical instrument and including a switch for activating and deactivating said electrical instrument.

Claims

6. A time controlled safety lock comprising a locking member for locking the door of a safe or the like and adapted to be withdrawn along a predetermined path for permitting opening of the door; a blocking member movable between a blocking position located in the path of said locking member to prevent withdrawal of the latter and an unblocking position completely withdrawn out of said path; at least one clockwork mechanism cooperating with said blocking member for moving the latter within a predetermined time from said blocking to said unblocking positions; transmission means between said clockwork mechanism and said blocking member for moving said blocking member during a first part of said predetermined time period at a uniform rate towards said unblocking position and then at a higher rate during the remaining part of said predetermined time period; and indicating means cooperating with said blocking member for disclosing at a location outside the door the time controlled blocking of the lock.

13. A time controlled safety lock comprising a locking member for locking the door of a safe or the like and adapted to be withdrawn along a predetermined path for permitting opening of the door; a blocking member movable between a blocking position located in the path of said locking member to prevent withdrawal of the latter and an unblocking position completely withdrawn out of said path; at least one clockwork mechanism cooperating with said blocking member for moving the latter within a predetermined time from said blocking to said unblocking position; and indicating means cooperating with said clockwork mechanism for disclosing at a location outside the door the time controlled blocking of the lock, said indicating means including an electrical instrument and including a switch for activating and deactivating said electrical instrument.