EP1323660A1 - Safety brake for elevator system - Google Patents

Abstract

A force (F1) is produced by e.g. a spring (27) on the piston (22a), to operate the braking unit (7). A further unit (23) produces a second force (F2), working against the first.

Description

The invention is based on a safety brake for Elevator systems according to the preamble of the first claim.

A brake safety device is known from EP 0 648 703 B1 known for an elevator car in which a braking device attacks on the guide rail of the elevator car. The of the braking device exerted on the guide rail Braking force is regulated by a control device so that the deceleration values in one for the passengers remain tolerable. The braking device is in essentially hydraulic by means of a pressure pump and a Pressure accumulator actuated, the braking force on one a control device engaging control valve is set becomes.

A safety disc brake is known from EP 0 465 831 B1 known for lifts in which the braking force by means of springs and brake lever is applied to the brake disc. By an electromagnetic one acting against the spring force The brake can be released in the opposite direction. By such Device is guaranteed at all times in the event of a power failure, that the brake is applied and the elevator is no longer moving. With increasing braking force requirements, the electromagnets are like also the switching means for mastering the Noise problems are an important cost factor.

US 6193026 B1 discloses a brake for an elevator system, in which a preloaded spring is provided to a Braking element against a guide rail of an elevator car to press. To control those acting on the braking element Braking force is provided with which one of the Counteracting force of the spring on the Brake element is exercisable. This counterforce becomes hydraulic generated by a force by means of an electromagnet generates a piston and this force with a pressure medium in a pressure medium volume between the piston and the Brake element is transferred to the brake element, the Pressure medium volume on the braking element is shaped such that the force thus transmitted counteracts the force of the spring. The piston is dimensioned so that the on the Braking element acting counter force greater than that on the Piston force is exerted. The pressure medium therefore has Function of a booster for the on the piston acting forces. The construction of this brake is complex, especially with regard to the shape of the Brake elements and the housing that surrounds the brake element because on the one hand the spring directly on the braking element is coupled and on the other hand a counterforce to the power of The spring is transferred hydraulically to the brake element got to. Furthermore, the efficiency of such a brake in Operation is not optimal when the brake for large braking forces should be interpreted or if the brake in different operating conditions different sizes Should generate braking forces. The latter would be the case if the Brake both for operation as a safety brake Elevator car as well as for operation as a holding brake Elevator car should be designed.

The invention has for its object a constructive simple, operable with high efficiency To create a safety brake for elevator systems.

According to the invention, this object is achieved by Safety brake that has the features of the first claim having.

This safety brake includes a braking device one or more movable brake elements, each - applied with a braking force - with a suitable one Can be brought into contact with a reference surface To achieve braking effect. Under "Activate the Brake device "is a measure in the following understood that generates a finite braking force or for Contributes to increasing the braking force. Under "Solve the Brake device "is a measure in the following understood, which contributes to a reduction in braking force.

The braking force acting on a braking element is thereby that creates a force on a movable piston acts with a pressure medium in a pressure medium volume between the piston and the brake elements on the respective Brake element is transmitted, for example hydraulically. Under the term "force acting on a movable piston acts ", can also be the resultant of several Partial workers independent by different means generated by each other and directly or indirectly the piston act, are understood.

According to the invention is to generate a on the piston acting force provided a device which Means for producing a first acting on the piston Force for actuating the braking device and means for Generation of a second force acting on the piston, which counteracts the first force. The on the The force acting on the piston is therefore the result of all Partial forces in with the first and the second force Related. So the first force is an actuation causes the braking device, the first force must be such be directed with respect to the direction of movement of the piston, that the piston has a compressive effect on the pressure medium. The second force should counteract and serve the first force releasing the braking device. It must be for this purpose so directed with respect to the direction of movement of the piston be that compression of the pressure medium reduces or the pressure of the pressure medium is reduced. If she Brake device is actuated or the size of the on Braking element acting braking force therefore depends on what mass the second force is the effect of the first force compensated.

Because the two opposing forces to operate and / or not to release the braking device directly on Attack the braking element, but on the pressure medium on the Brake element are transmitted, is the construction of the Brake elements and that adjoining the brake element Components relatively simple in terms of shape.

In the safety brake according to the invention there is a functional separation between "operating the Braking device "and" releasing the braking device " realized. This is achieved in that the first and the second force independently by different means be generated. This functional separation offers one Starting point for an optimization of the safety brake in the In terms of their efficiency since the means of production the first force and the means of producing the second Force can be optimized independently of each other.

In one embodiment of the safety brake, the piston is dimensioned so that the pressure medium like a Power amplifier works, i.e. that the on a braking element braking force is greater than that on the piston Acting force. Such a safety brake has the Advantage that both the actuation of the braking device serving first force as well as that of releasing the Braking device serving second force are increased because attack both forces on the same piston and the Resulting both forces the magnitude of the braking force certainly. The greater the power gain through that Pressure medium, the smaller the first force be selected to a predetermined maximum braking force achieve, and the smaller the second force can be chosen to release the braking device. This connection can be used to measure the efficiency of the Optimize safety brake.

The advantages of the invention include that means to generate the forces acting on the piston are available with which sufficiently large forces with a relatively small amount of energy is generated can. So energy storage, for example, based of springs or permanent magnets. Such Systems generally require little energy in operation, because they can store energy and little energy is needed to convert the stored energy into to control mechanical work. With a biased For example, spring can still operate even in the event of a power failure a force is exerted on the piston. The Tension state of the spring with simple means and little Energy expenditure can be checked, for example with electromechanical means that the spring when current flows keep excited and their relaxation in the event of a power failure enable automatically. This principle is also applicable to others Lift mechanism transferable, for example Permanent magnets that are movable relative to each other in one Spacing are arranged so that they are mutual attract or repel.

Is the piston dimensioned so that the pressure medium is like a Power booster works, then energy storage that could the piston cooperate, designed relatively small and the moving masses, for example the pistons, can also be designed small. Under these Conditions can also be used to release the braking device usable means, for example electromagnets and / or Lift mechanism and / or lever systems, relatively small be interpreted. Furthermore, for example Components from vehicle technology are adopted, which in large quantities and therefore manufactured inexpensively can be. It is reliability and security guaranteed, because in vehicle technology similarly high Security and reliability requirements become like elevator technology.

Within the framework of this concept it is possible to function as a Holding brake and the function of a safety brake Elevator system in a single safety brake integrate. Catch and holding brakes are their function designed accordingly for loads of different sizes. The The safety brake of an elevator car must be a much larger one Brake the mass or hold it as an appropriate one Holding brake. With the safety brake according to the invention can have different sizes in different ways Braking forces can be realized.

Starting from a master brake cylinder with a movable one Pistons can, for example, generate a means force acting on the piston to actuate the braking device be designed so that it is controlled depending on the situation braking forces of different sizes are generated.

In a safety brake training is a means of Generation of a third force, which is additive to the first Force acts on the piston, provided. A variation of the Braking power can be achieved in a controlled manner by that Means for generating the third force optionally one transfers predetermined force or no force to the piston. This can be achieved by controlled manufacturing or Breaking a mechanical connection between the agent to generate the third force and the piston.

As part of this concept, different sizes can be used Braking forces, for example, also with a plurality of preloadable springs are realized, their effects can be combined with one another as required several preloaded springs alone or together combined in a parallel and / or serial arrangement Be connected to the piston. Advantageous This concept is that control over which of the Springs are brought into connection with the piston simple means and low energy consumption can be made possible. For example, relaxation a spring with movable mechanical means, for example lever elements and devices that the check the current alignment of the lever elements, initiated or blocked and thus controlled. to The lever elements can increase efficiency be strengthened. The orientation of the Lever elements can be electromechanical, for example with Check springs and electromagnets in such a way that in the event of a power failure, the Braking device is triggered.

Another variant for the training of safety brake according to the invention as integrated holding and safety brake is based on the use of an additional (second) movable piston. In this case, two Alternatively and independently, pistons each with a force or several forces are applied. For this purpose in each case the action of one of the pistons on the pressure medium controlled be prevented. This can be achieved by means of a valve which, when closed, has a Piston separates from the part of the pressure medium that is on the brake elements acts to generate the braking force, so that the respective braking force comes exclusively from the other Piston can be influenced. Another variant is that a controllable blocking means is provided with a movement of a piston during a controllable period in a given position can be blocked, blocking the movement by means of a control signal can be canceled. As a blocking agent a movable mechanical means can serve for example an electromechanically actuated lever or Bars.

By appropriately dimensioning the pistons and appropriate timing of the individual pistons acting forces can be of different sizes in this way Braking forces are generated with the same braking device. With this configuration, it is with regard to the Efficiency makes sense to dimension both pistons so that the pressure medium is force-boosting on the brake elements acts.

Further advantageous embodiments of the invention result itself from the exemplary embodiments and the subclaims.

Fig. 1

eine schematische Darstellung eines Aufzugschachtes für einen verfahrbaren Aufzug;

Fig. 2

eine Draufsicht auf den Schacht gemäss Fig. 1;

Fig. 3

eine Antriebseinheit für einen Aufzug;

Fig. 4

einen Querschnitt durch eine Bremseinrichtung;

Fig. 5

einen Querschnitt durch eine weitere Ausführungsform einer Bremseinrichtung;

Fig. 6

eine schematische Darstellung einer Ausführungsform der erfindungsgemässen Sicherheitsbremse;

Fig. 7

eine schematische Darstellung einer weiteren Ausführungsform der erfindungsgemässen Sicherheitsbremse für den Betrieb als integrierte Halte- und Fangbremse; und

Fig. 8

eine weitere integrierte Halte- und Fangbremse gemäss der Erfindung.

Exemplary embodiments of the invention are explained in more detail below with reference to the drawings. Identical elements are provided with the same reference symbols in the various figures. The direction of flow of the media is indicated by arrows. It shows:

Fig. 1

a schematic representation of an elevator shaft for a movable elevator;

Fig. 2

a plan view of the shaft of FIG. 1;

Fig. 3

a drive unit for an elevator;

Fig. 4

a cross section through a braking device;

Fig. 5

a cross section through a further embodiment of a braking device;

Fig. 6

a schematic representation of an embodiment of the safety brake according to the invention;

Fig. 7

a schematic representation of another embodiment of the safety brake according to the invention for operation as an integrated holding and catching brake; and

Fig. 8

a further integrated holding and catching brake according to the invention.

It is only for the immediate understanding of the Invention essential elements shown. Not shown are, for example, ropes for moving the elevator car, electrical lines, etc. Communication links between control devices and devices designed by the respective control devices controlled or regulated are through by the respective inspection body outgoing arrows indicated, if not on a graphic Representation of the communication connections of simplicity was waived for the sake of

In Fig. 1 and Fig. 2 is an elevator shaft 1 with a Elevator car 3 movable along guide rails 2 shown. The elevator car is in a support frame 4, that of an upper yoke 5, from side plates 6 and one not shown lower yoke. On the support frame 4 are arranged braking devices 7, which by means of a Recess 9 a free leg 8 of the guide rails 2nd enclose. The free leg 8 can for the engagement of the Braking device and to improve braking behavior be coated accordingly. The braking device 7 can can be attached to the upper yoke 5 as shown, possible is, for example, also an attachment to the bottom Yoke or both. The braking device is a Pressure medium device 10 and pressure medium lines 11a and 11b supplied with pressure medium. It will be a first and a second pressure medium line 11a and 11b used and the two braking devices 7, each with two Pressure fluid lines addressed. The braking devices are designed so that if one of the Fluid lines 11a or 11b always the elevator car 3 still secure thanks to the remaining pressure medium line can be stopped. By means of a control device 12, expediently an electronic control, the via the pressure medium device 10 and the Pressure medium lines 11a, 11b amount of pressure medium supplied can be set. The pressure medium device 10 is there designed so that if the control device fails 12 or other malfunctions the elevator car is stopped.

3 is a further possibility for the arrangement of the Brake device 7 shown. In contrast to the above For example, the braking device 7 acts directly on one Elevator motor 13, the elevator via a shaft 14 and not further illustrated means such as ropes. The Braking device 7 engages over recess 9 a brake disc 15, which on the shaft 14 with the Elevator drive 13 is connected and when the Braking device brakes the elevator motor and if necessary stops.

In Fig. 4, the braking device 7 is schematically in Cross section shown. In the braking device 7 is a Brake cylinder 16a with a cylinder space 17 and a piston 18 arranged. On the outside of the cob 18 is on the the brake disc 15 or the free leg 8 facing Side a braking element 19 in the form of a brake plate or a brake pad arranged. Other known Elements such as seals etc. are not shown. The Braking device 7 according to FIG. 4 contains another one Brake cylinder 16b, which corresponds to the brake cylinder 16a is constructed. Will now over the pressure medium line 11a Brake cylinder 16a and via the pressure medium line 11b Brake cylinder 16b supplied with pressure medium, are by the pressure medium pressed into the cylinder space 17 the pistons 18 and thus the braking elements 19 with a defined Braking force against the brake disc 15 or the free leg 8 pressed and there is a braking effect due to friction.

5 is another embodiment of a Brake device 7 shown. In this example is only a brake cylinder 16a is arranged in the brake device 7. On the opposite side is a braking element 19a directly with the supporting structure of the braking device 7 connected, it becomes a so-called outer shoe brake educated. The braking device 7 is not further shown means slidably suspended. Now over the pressure medium line 11 a pressure medium into the cylinder space 17 pressed, then the piston 18 is moved until the Brake elements 19, the brake disc 15 or the free leg 8 touch. Because of the effect of the braking force that the Brake element 19 on the brake disc 15 or the free one Exercises leg, the braking device 7 is in the Opposite direction to the direction of movement of the piston 18 shifted until the braking element 19a also the Brake disc 15 or the free leg 8 touches. At the Releasing the brake is the braking device 7 because of it movable arrangement again free.

6 shows an embodiment of the invention Safety brake with a variant of the Pressure medium device 10 is shown schematically. On Master brake cylinder 20 is provided with a reservoir 21 connected, which the master cylinder 20 with pressure medium supplied and compensates for any loss of pressure medium. About a piston rod 22 is in the master cylinder 20 Piston 22a operable, which when the Piston rod 22 in the direction of the master brake cylinder 20 Pressure medium into the leading from the master cylinder 20 Pressurizing medium lines 11a and 11b. The cylinder space 17 and the interior of the master cylinder 20 and the Pressure medium lines 11a and 11b define a pressure medium volume, that is filled with the pressure medium. On the opposite side of the piston rod 22 is one arranged electromagnetic tightening device 23, the Functionality is known for example from speakers. A plate 26 is fixedly attached to the piston rod 22 which supports a spring 27 surrounding the piston rod. The spring 27 is supported on the opposite side the outside of the electromagnetic tightening device 23 from the stationary with respect to the master cylinder 21st is arranged. The spring 27 is in its longitudinal direction Compared to their relaxed state and compressed exerts a force F1 on the plate 26 and thus on the piston 22a. By the force F1, the piston rod 22 is thus in Direction of the master cylinder 20 pressed and pressure medium in the leading from the master cylinder 20 Pressurized fluid lines 11a and 11b pressed. In the Braking device 7 are then the pistons 18 on the Brake disc 15 or the free leg 8 moves and the Brake elements 19 - acted upon by the braking force - to the Brake disc 15 or the free leg 8 pressed to Braking the elevator car.

In order to achieve a high degree of efficiency, it is based on the Pressure medium in the master cylinder 20 acting surface of the Piston 22a dimensioned so that on one of the braking elements 19 acting braking force is greater than the force F1.

The electromagnetic tightening device 23 includes one Electromagnet with a coil 25 and an armature 24, which attached to the end facing away from the master cylinder 20 is and along the central axis of the coil 25 together with the Piston rod 22 is movable. With this arrangement, a Current flow through the coil 25 are directed such that on the armature 24 and thus on the piston rod 22 a Counterforce F2 to force F1 of spring 27 acts to Piston rod 22 in the direction of the electromagnetic To move the tightening device 23. The current flow through the Coil 25 takes place depending on signals from the Control device 12. By regulating the by Coil 25 flowing current can thus brake device 7 be solved.

In the event of a failure of the control device 12 or one Power failure, the coil 25 produces no electromagnetic Force on the armature 24 and the piston rod 22 is by the Spring force F1 in the direction of the master cylinder 20 pressed. As a result, the braking device 7 is actuated. So is a safe braking of the Elevator cabin guaranteed.

The spring 27 can also by another energy accumulator to be replaced, on the condition that in the event of a malfunction it is guaranteed that the braking force by the Lift mechanism is exerted on the master cylinder.

A not shown can be in the elevator car Acceleration sensor can be arranged with the Control device 12 cooperates. This allows the Control device 12 adjust the braking force so that not high, uncomfortable for the elevator car users Accelerations occur.

Figures 7 and 8 show an example of how in the context of Invention an integrated holding and catching brake realized can be.

Fig. 7 shows an embodiment of the safety brake, the can be operated as an integrated holding and catching brake. The 7 differs from that 6 only by a few additional components that provide additional functionality introduce: a spring 40, which like the spring 27 in Longitudinal direction of the piston rod 22 extends and between the electromagnetic tightening device 23 and a movable Plate 41 is supported; a two-armed lever 45 which around a fulcrum 46 is rotatably supported; an electromagnet 49, with one on one end of the lever 45 electromagnetic force can be exerted; a spring 47, with on one end of the lever 45 - like an arrow indicated - another force can be exerted.

These additional components work together as follows. The Spring 40 is in its arrangement according to FIG Compresses longitudinally and exerts on the plate 41 Force F3 towards the master cylinder 20 (as by indicated by the arrow indicated in FIG. 7). Under the Effect of force F3 would plate 41 towards the Master cylinder 20 accelerates when not through additional measures are prevented.

The lever 45 is by means of the electromagnet 49 generated electromagnetic force against the action of Force of the spring 47 controlled within a limited Angular range rotatable about the pivot point 46 and in at least two extreme angular positions stable. One of these extreme positions of the lever 45 is shown in Fig. 7: In this The electromagnet 49 is activated, i.e. with a stream supplied, and the electromagnet 47 near the end of the lever 45 held so that the other end of the lever 45 in Contact with the plate 41 and the plate 41 - against the Effect of force F3 of the spring 40 - in a stable Holds position at a distance from the plate 26. It is the spring 40 and the plate 41 so with respect to the spring 27 and the plate 26 aligned that the braking device 7th by means of the forces F1 and F2, mediated by the spring 27 or the electromagnetic tightening device 23, operated can be.

The other extremely stable angular position that the lever 45 is characterized by the fact that the Electromagnet 49 is currentless and the lever 45 one of the Spring 47 assumes certain equilibrium position. in the In the present case, this equilibrium is due to a appropriate choice of the bias of the spring 47 so determined that the lever 47 does not touch the plate 41 or the plate 41 not against the action of the force F3 of the spring 40 in one is able to maintain a stable position. Consequently, the plate 41 released and in the direction of the master cylinder 20 emotional. The lengths of the springs 27 and 40 are such matched and the plates 26 and 41 such shaped that the spring 40 towards the Master brake cylinder 20 expands until plate 41 is finally blocked by the plate 26. In this The forces F1 and F3 of springs 27 and 40 act in this position additive to the piston 22a in the master cylinder 20.

The control device 12 is designed such that the Electromagnet 49 and the electromagnetic tightening device 23 can be controlled independently of one another, such that that the currents of the electromagnet 49 and the Coils 25 flowing currents to predetermined values be managed. By appropriate control of the Time course of these currents can therefore be reached that the piston 22a with the force F1 or with the Resulting forces F1 and F3 are applied, provided the coil 25 is de-energized and thus the force F2 is 0. By a suitable choice of the current strength of the coil 25 current flowing through the springs 27 and 40 generated forces are fully or partially compensated.

Based on that shown in FIG. 7 Safety brake can be an integrated holding and catching brake can be realized by the springs 27 and 40 suitable be dimensioned. The spring constant and the preload the spring 27 is chosen so that by the action of the force F1 on the piston 22a for operation as a holding brake transmit the desired braking force to the braking elements 19 becomes. The size of the spring 27 is adapted Spring constant and the preload of the spring 40 selected so that through the action of forces F1 and F3 on the piston 22a the braking force required for operation as a safety brake is transmitted to the brake elements 19.

An integrated holding and catching brake based on the 7 is designed so that at a general power failure to operate as a safety brake is activated because under this condition the force F2 is 0 and the lever 45 is also aligned in this way will that the expansion of the spring 40 in its longitudinal direction is enforced.

7 after operation as To operate the safety brake again as a holding brake, the Plate 41 against the force F3 of spring 40 from plate 26 be removed so that only the forces F1 and F2 on the Pistons 22a act and the spring 40 without influencing the Piston 22a is. To achieve this, one in FIG. 7 Not shown device provided that - activated by signals from the control device 12 - the plate 41 in moved such a stable position in which it from the lever 45th after a suitable activation of the electromagnet 49 and a corresponding alignment of the lever 45 in a Distance to plate 26 can be kept. On a such device can also be dispensed with, since under realistic conditions while operating a Elevator relatively rarely situations in which the Function of a safety brake must be activated. It is therefore acceptable to reset the safety brake in carry out the operation as a holding brake by service personnel allow.

The spring 40 is dimensioned according to FIG. 7 so that it Spring 27 surrounds without touching it. The spring 40 is like the spring 27 is guided around the piston rod 22. Plate 41 has - as indicated in Fig. 7 - a central opening through which the piston rod 22 and the spring 27th are movable.

Alternatively, the springs 27 and 40 could also be arranged side by side be arranged without one of the springs surrounding the other. The means for coupling the springs to the piston rod 22 - i.e. the plates 26 and 41 - could by other variants can be replaced with the same function.

8 shows a further embodiment of the Safety brake that acts as an integrated holding and catching brake is operable. The safety brake according to FIG. 8 differs from the safety brake according to FIG. 6 through some additional components that an additional Bring functionality. The safety brake includes in addition to that already described in connection with FIG. 6 Piston 22a another piston 55a, which in Master cylinder 20 interacting with the pressure medium stands and on a movable in its longitudinal direction Piston rod 55 is arranged. The master cylinder 20 opposite end of the piston rod 55 is via a spring 60 with a (in Fig. 8 by a vertical line indicated) connected stationary surface, the spring 60 is biased such that the spring 60 on the Piston rod 55 acts with a force F3 along the Piston rod 55 in the direction of the master brake cylinder 20 is directed.

The safety brake according to FIG. 8 has springs 27 and 60 thus via two means for generating a force which independently to increase the pressure in the Pressure medium volume and thus to generate one on one the braking elements 19 acting braking force can be used can. In the master cylinder 20 is in the vicinity of the piston 22a a partial area of the pressure medium volume by means of a Chamber 50 delimited. The chamber 50 has an opening 50a on which can be actuated electromagnetically Valve 51 can be opened or closed tightly. The Valve 51 comprises a closure flap 53 and one with the Closure flap 53 interacting electromagnetically Electromagnet 52 for opening or closing the opening 50a. By closing the opening 50a it is possible to Action of the force F3 in the pressure medium to a pressure generate which is greater than the pressure caused by action the force F1 in the chamber 50 or inside the Master brake cylinder 20 can be generated.

In order to be able to move the piston rod 55 in a controlled manner, one is electromagnetic propulsion device 65 is provided, which - As indicated in Fig. 8 by an arrow - with the Control device 12 is connected. The electromagnetic propulsion device 65 includes under another an electromagnet 65, which is electromagnetic the piston rod 55 acts to exert a force F4 thereon to exercise, which counteracts the force F3. If necessary, can the electromagnet 65 can be powered to the To fully or partially compensate for the effect of force F3.

The piston rod 55 can, if necessary, also without using the Propulsion device 65 and against the action of force F3 in be held in a predetermined position. To do this a two-armed locking lever 70 is provided, which is rotatably mounted about a pivot point 71. An end the blocking lever 70 is coupled to a spring 82 which the end remote from the blocking lever 70 (with not represented means) is kept stationary. Against the force the spring 82, the blocking lever 70 using a Electromagnet 81 over an angular range between two stable extreme positions pivoted about the pivot point 71 become.

One of these extreme locations is shown in Fig. 8 and will be taken when the electromagnet 81 with a predetermined Minimum amount of electricity is supplied. On this condition is the blocking lever 70 is deflected such that one of its Ends into a groove 69 on the locking lever 70, the Locking lever 55 is arranged so that the piston rod 55 fixed in a stable position despite the action of force F3 is. The force F3 is then from the blocking lever 70 or its Camp added.

The other of these extreme positions is from the blocking lever 70 taken when the electromagnet 81 is de-energized and the Blocking lever 70 under the influence of the spring 82 in a stable situation is forced. This location is chosen so that the piston rod 55 is not through the blocking lever 70 is blocked. The forces F3 act under this condition and F4 via the piston 55a to the pressure medium in Master brake cylinder 20.

The safety brake according to FIG. 8 can be as follows Holding brake and operated as a safety brake.

8 shows the safety brake in one for the Operation as a holding brake characteristic condition: the Opening 50a is open; the electromagnet 81 is powered supplied and the piston rod 55 thus in a stable position blocked. In this state, the piston 55a is immobile and without influencing the pressure in the pressure medium. The Electromagnet 66 can be de-energized because of the forces F4 and F3 without affecting the size of the Brake elements 19 are acting braking forces. In this Condition can be the pressure in the pressure medium volume - controlled through the control device 12 - with the piston 22a in Depending on the forces F1 and F2 are controlled. Accordingly, the mode of operation corresponds to the safety brake in this state the mode of operation of FIG. 6 shown safety brake.

To apply the safety brake according to FIG. 8 as a safety brake operate, the current flow through the electromagnet 52nd and 81 interrupted. The blocking lever 70 is under the Action of the spring 82 pivoted such that the piston rod 55 no longer blocked, but under the action of forces F3 and F4 is free to move. The dimension of the piston 55a and the force F3 are coordinated so that the means of the piston 55a, the pressure that can be generated in the pressure medium is greater than the pressure in the pressure medium with the piston 22a below Effect of the force F1 can be generated. Under this On condition, the valve 51 closes the opening 50a and the the braking elements 19 acting braking forces are determined by the magnitude of the force F3, provided the electromagnet 66 is de-energized, or the magnitude of the forces F3 and F4, if a current flows through the electromagnet 66.

8 after operation as To operate the safety brake again as a holding brake is the Force F4 controlled so that the piston rod 55 in one Position is moved in the position using the locking lever 70 can be fixed.

The safety brake according to FIG. 8 could also be used without the Blocking lever operated as integrated holding and catching brake become. However, the magnitude of the force F4 would then have to be be regulated accordingly to operate as a holding brake to partially compensate the force F3. This mode of operation is less efficient in terms of efficiency because the electromagnet 66 should be constantly supplied with current, although relatively rare during the operation of an elevator Situations occur that apply the safety brake make necessary. Operation of the blocking lever 70 can be very efficient, however, because the two arms of the Blocking lever 70 can be dimensioned so that a by means of the electromagnet 81 on an arm of the Blocking lever 70 applied force by any factor is reinforced.

The propulsion device 65 can also be dispensed with. The safety brake could still be used as a safety brake be, resetting the safety brake in the Operation as holding brake also by the intervention of Service personnel can be made.

8 is constructed in such a way that automatically in the event of a general power failure Operation as a safety brake is switched. In this case the piston rod 55 no longer by the blocking lever 70 blocked and the electromagnet 66 de-energized, i.e. F4 equal 0th

The invention is not based on those shown and described Embodiments limited. According to another The pressure medium lines can also be a variant, for example address only one braking device at a time. Farther the springs do not have to be prestressed under pressure. she could also be biased on train. In the latter case would have to be supported on stationary or movable parts the safety brake different from those shown Examples modified appropriately.

In Fig. 6, the pressure medium lines 11a and 11b shown in broken lines to indicate that this Lines can be run along any route. Around the device shown in Fig. 6 to a more compact It would also be conceivable to develop a form further spatial separation between the master cylinder 20 and the To waive braking device 7. Such a configuration could without any special pressure medium lines between the Master brake cylinder 20 and brake cylinders 16a and 16b will be realized. The master cylinder 20 and the Braking device 7 become a particularly compact Unit connected when the pressure medium volume between the Piston 18 and the piston 22a and 55a is designed such that it doesn't come in a plurality of separate ones, just about Through openings interconnected chambers is divided. In this way it is possible to To make the safety brake so compact that everyone Components of the safety brake including the Pressure medium device 10 arranged on the elevator car 3 can be, if necessary, right next to the Brake elements 19, 19a.

The control device 12 can be used to control the Elevator system integrated and stationary at a suitable Place in the elevator system. It is also possible to use the functions of the control device 12 to implement a separate facility at the Elevator car is arranged. For example, it is conceivable the control device 12 as one fixed to the cabin to train electronic circuit. This circuit can via a communication link to the elevator control have, for example, to send control signals and / or to receive and / or status information regarding the Elevator system and / or with regard to the safety brake send and / or receive.

The in the illustrated embodiments of the Safety brake provided springs and electromagnets could of course by other means of generating a Force to be replaced. These funds should be expedient be controllable to actuate or release the To enable a safety brake at specified times and if necessary the size of the force to be generated to the adapt to the respective requirements.

Claims (18)

Safety brake for elevator systems, with a braking device (7), which comprises one or more movable brake elements (19), each with a braking force, with a movable piston (22a, 55a), with a device for actuating and / or releasing the braking device (7) by means of at least one force (F1, F2, F3, F4) acting on the piston (22a, 55a), which by means of a pressure medium in a pressure medium volume (20, 17, 11a, 11b) between the brake elements (19) and the piston (22a, 55a) can be transferred to the brake elements (19) in order to generate the respective braking force, characterized in that the device comprises: Means (27, 40, 60) for generating a first force (F1, F3) acting on the piston (22a, 55a) for actuating the braking device (7) and Means (23, 65) for generating a second force (F2, F4) acting on the piston (22a, 55a) which counteracts the first force (F1, F3). Safety brake according to claim 1, characterized in that the piston (22a, 55a) is designed such that the braking force is greater than the force acting on the piston (F1, F3). Safety brake according to one of claims 1 or 2, characterized in that the size of the second force (F2, F4) is variable and means (12) are provided for checking the size of the second force. Safety brake according to one of claims 1-3, characterized in that the means for generating the first force (F1, F3) is designed such that the size of the first force can be changed in a controlled manner. Safety brake according to one of claims 1-3, characterized in that the device comprises a means (40) for generating a third force (F3) which acts on the piston (22a, 55a) in addition to the first force (F1). Safety brake according to claim 5, characterized in that controllable means (41, 45, 49) for establishing or removing a mechanical connection between the means (40) for generating the third force (F3) and the piston (22a) are provided in order to To control the action of the third force (F3) on the piston (22a). Safety brake according to one of claims 1-3, characterized in that a movable second piston (55a) and a means (60) for generating a third force (F3) which acts on the second piston (55a) is provided, the second piston (55a) is connected to the pressure medium volume (20, 17, 11a, 11b) and the third force (F3) can be transmitted via the pressure medium to the brake elements (19) in order to actuate the brake device (7). Safety brake according to claim 7, characterized in that means (65) are provided for generating a fourth force (F4) which acts on the second piston (55a) and is directed in such a way that it counteracts the third force (F3). Safety brake according to one of claims 7 or 8, characterized in that blocking means (69, 70) are provided for blocking the second piston (55a) for a period of time controllable by control signals (12). Safety brake according to one of Claims 7-9, characterized in that the first piston (22a) can be separated from the pressure medium, which acts on the brake elements (19), by means of a valve (51), the pressure of the pressure medium with the second piston (55a) can be influenced. Safety brake according to one of claims 7-10, characterized in that the braking device (7) can be actuated by the action of either one of the pistons (22a, 55a), the two pistons being designed such that the braking force takes on different values. Safety brake according to one of Claims 1-11, characterized in that the means (27) for generating the first force (F1) has a spring (27, 40, 60) or a force accumulator of another type and / or the means (23) for Generation of the second force (F2) comprises an electromagnet (25). Safety brake according to one of Claims 5-11, characterized in that the means for generating the third force (F3) has a prestressable spring (40, 60) or an energy store of another type. Safety brake according to Claim 13, characterized in that the spring (40, 60) can be held in a tensioned state without acting on or moving the piston (22a, 55a), and in that the spring (40, 60) can be relaxed in a controlled manner to move the piston (22a, 55a) and generate the braking force. Safety brake according to Claim 14, characterized in that the spring (40, 60) can be held in the tensioned state by movable mechanical means (45, 70). Safety brake according to one of claims 1-15, characterized in that the piston (22a) is connected to the pressure medium inside a master brake cylinder (20) and the master brake cylinder is connected to the brake device (7) via at least one pressure medium line (11a, 11b) is. Elevator system with a safety brake according to one of Claims 1-16, characterized in that the braking device (7) is arranged in such a way that the braking elements (19) come into contact with a guide rail (2) of an elevator car (7) when the braking device (7) is actuated. 3) or in contact with a brake disc (15) of an elevator drive (13). Elevator system according to claim 17, characterized in that the safety brake is designed as an integrated holding and catching brake.

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