EP1930282A1 - Braking device for holding and braking a lift cabin in a lift facility and method for holding and braking a lift facility - Google Patents

Abstract

The equipment has an actuator (4) releasing a brake wedge mount (13) with a movable brake lining, where the equipment biases a tightening unit (3), the mount and the lining against a brake track with a biasing force in an unreleased activated state. A part of the lining retightens the tightening unit, applies a tightening force on the mount and the lining and produces a braking force directed against the direction of travel of the equipment in the state and a following relative movement of the equipment in a direction of travel, where the braking force is defined by the tightening force. An independent claim is also included for a method of holding and braking an elevator car in an elevator installation with a brake equipment.

Description

The present invention relates to a braking device for holding and braking an elevator car in an elevator installation and a corresponding method. The elevator installation includes an elevator cage which is arranged to be movable along one or more rails in an elevator shaft in up and down direction. The elevator car is driven by a drive either directly or indirectly by means of suspension and the car is held and secured by a braking device. In general, the cabin further includes a counterweight which is connected via the suspension means to the cabin. The counterweight partially compensates for the weight of the cab.

In the operation of such a lift system, three different braking situations are to be considered: holding the car at a floor stop; a braking of the cabin with intact suspension means (hereinafter also referred to as emergency stop); and a deceleration of the car in the event of failure of the suspension element (hereinafter referred to as free-fall braking).

In this case, different braking forces must be applied in the different braking situations - for example, in a free-fall braking, the braking force of the full, no longer at least partially compensated by the counterweight weight of the car to maintain the balance. If the brake device arrangement comprises two redundant brake devices, then an emergency stop should also be ensured by only one brake device, which consequently must provide twice the brake force for reasons of reliability, for example at a landing stop.

FLN_H:

erforderliche Haltekraft zum Halten der Kabine im Stillstand bei 50% Gegengewichtsbalancierung

Nutzlast:

mögliche Zuladung der Kabine (Beispiel Nutzlast = 1000kg)

g:

Erdbeschleunigung , 9,81 m/s2

µ:

Reibwert (Beispiel µ = 0.2)

$${\mathrm{FLN}}_{\mathrm{H}}\mathrm{=}\left(1000\mathrm{/}\mathrm{2}\mathrm{\times }\mathrm{g}\right)\mathrm{/}\left(0.2\mathrm{\times }\mathrm{2}\mathrm{\times }\mathrm{2}\right)=6150N$$

If the braking device acts frictionally, the normal forces which the braking device must make available differ according to the different braking forces. For example, in a brake assembly that includes two braking devices each having two brake circuits, it may assist in holding the cab One floor stop requires a normal force FLN _H of at least 6150 N per brake circuit. $${\mathrm{FLN}}_{\mathrm{H}}\mathrm{=}\left(\mathrm{payload}\mathrm{/}\mathrm{2}\mathrm{\times }\mathrm{G}\right)\mathrm{/}\left(\mathrm{\mu }\mathrm{\times }\mathrm{2}\mathrm{\times }\mathrm{2}\right)$$

FLN _H :

Holding force required to hold the car at standstill with 50% counterweight balance

Payload:

possible payload of the cabin (example payload = 1000kg)

G:

Gravitational acceleration, 9.81 m / s2

μ:

Coefficient of friction (example μ = 0.2)

$${\mathrm{FLN}}_{\mathrm{H}}\mathrm{=}\left(1000\mathrm{/}\mathrm{2}\mathrm{\times }\mathrm{G}\right)\mathrm{/}\left(0.2\mathrm{\times }\mathrm{2}\mathrm{\times }\mathrm{2}\right)=6150N$$

$${\mathrm{FLN}}_{\mathrm{N}}\mathrm{=}\left(\mathrm{1.5}\mathrm{\times }1000\mathrm{/}\mathrm{2}\mathrm{\times }\mathrm{g}\right)\mathrm{/}\left(0.2\mathrm{\times }\mathrm{1}\mathrm{\times }\mathrm{2}\right)=18600N\mathrm{.}$$

In an emergency stop now according to the request with only one braking device a car at a payload of 125%, at least not further accelerated. Accordingly, in the above example, the required normal force FLN _{N increases} to: $${\mathrm{FLN}}_{\mathrm{N}}\mathrm{=}\left(\mathrm{1.5}\mathrm{\times }\mathrm{payload}\mathrm{/}\mathrm{2}\mathrm{\times }\mathrm{G}\right)\mathrm{/}\left(\mathrm{\mu }\mathrm{\times }\mathrm{1}\mathrm{\times }\mathrm{2}\right)$$

$${\mathrm{FLN}}_{\mathrm{N}}\mathrm{=}\left(\mathrm{1.5}\mathrm{\times }1000\mathrm{/}\mathrm{2}\mathrm{\times }\mathrm{G}\right)\mathrm{/}\left(0.2\mathrm{\times }\mathrm{1}\mathrm{\times }\mathrm{2}\right)=18600N\mathrm{,}$$

$${\mathrm{FLN}}_{\mathrm{F}}\mathrm{=}\left(1.8\times 1000\mathrm{/}\mathrm{1}\mathrm{,}\mathrm{2}\mathrm{\times }\mathrm{g}\right)\mathrm{/}\left(0.2\mathrm{\times }\mathrm{2}\mathrm{\times }\mathrm{2}\right)=26500N$$

In a freefall braking is further required that the fully loaded cab, can be safely delayed under the effect of all available braking devices. Using the example above and determining that the weight of the empty car is approximately 80% of the payload and the required minimum car delay of 0.2g, there is a required normal force FLN _F to brake the car by: $${\mathrm{FLN}}_{\mathrm{F}}\mathrm{=}\left(\mathrm{1.8}\mathrm{\times }\mathrm{payload}\mathrm{\times }\left(\mathrm{G}\mathrm{+}\mathrm{a}\right)\right)\mathrm{/}\left(\mathrm{\mu }\mathrm{\times }\mathrm{2}\mathrm{\times }\mathrm{2}\right)$$

$${\mathrm{FLN}}_{\mathrm{F}}\mathrm{=}\left(1.8\times 1000\mathrm{/}\mathrm{1}\mathrm{.}\mathrm{2}\mathrm{\times }\mathrm{G}\right)\mathrm{/}\left(0.2\mathrm{\times }\mathrm{2}\mathrm{\times }\mathrm{2}\right)=26500N$$

On the other hand, however, should not always act in the different braking situations, the maximum required for a freefall braking normal forces, as this heavily on the one hand, the brake device and the rail and on the other hand, much energy is required to the braking device, which should automatically close for safety reasons in case of failure of the power supply to ventilate during normal driving.

So far, each own brake devices are therefore provided for the different braking situations.
For example, from the DE 39 34 492 A1 a pure braking device for braking an elevator car known in which a movable brake pad by a Lifting device or by a movement of the elevator car, is pushed onto a wedge surface, which then delivers the movable brake pad under frictional engagement with the rail automatically. Only by this feed movement, a spring is tensioned, which can counteract an electromagnet to regulate the force acting on the movable brake pad normal force. This braking device is not suitable for holding an elevator car, since it requires a movement of the elevator car for actuating.
The EP 1 528 028 A2 describes a holding brake device in which a set back passive brake pad assumes the function of an active, biased by a compression spring against the rail and ventilated by an actuator brake pad when this brake pad fails. For this purpose, the braking device is floating. In this braking device, the same, defined by the spring tension normal force is always exerted on the brake pad upon activation or non-ventilated brake device. If such a braking device therefore assume both the holding and the emergency stop braking function, this normal force must be sufficient for braking and is thus oversized for the normal holding function. Such an oversized holding normal force, however, adversely loads the braking device and the rail and requires a high actuator energy for releasing the highly preloaded spring.

Object of the present invention is therefore to provide a braking device available that can exert different normal forces on brake pads upon activation of the braking device for holding and braking. In addition, the normal force for holding and thus a required for ventilating, or deactivating the braking device required actuator can be performed minimally.

To solve this problem, a braking device according to the preamble of claim 1 and a braking method of claim 16 further developed by the characterizing features.

A braking device according to the present invention, for holding and braking an elevator car in an elevator installation, which braking device is arranged to be movable relative to a braking track, along this braking track in two traversing directions, comprises a brake pad held in a receptacle which engages in frictional engagement with the braking track a movement of the braking device relative to the braking path in at least one of the two Verfahrrichtungen automatically delivers and thereby spans a first chip means that the Brake pad against the rail clamped with a clamping force, and can be released by an actuator.
The activated actuator releases the brake pad in normal driving mode, ie it removes it from the brake track and thus interrupts the frictional connection between them, as a result of which the brake device exerts no braking action. The braking device is thus deactivated. If the actuator is deactivated, the first clamping means presses the brake lining against the braking track and thus activates the braking device. The thereby exerted by the clamping means on the movable brake lining normal force FLN _H or pre-clamping force defines the frictional force between it and the brake track. According to the invention, the braking device is embodied such that, when the actuator and the stationary braking device are not ventilated, a retaining force which essentially corresponds to the prestressing force and which acts in both directions of travel can be generated. The pre-chip force is passed over the brake lining and the associated brake plate holder in such a way that the frictional force or the braking force can be used for holding, ie in particular the brake lining does not slip away within the scope of the intended holding force. The prestressing force can thereby be kept to a minimum and since the brake pad is automatically delivered relative to the braking track during a movement of the braking device or when the intended holding force is exceeded, ie moved in such a way that the first tensioning device is tensioned further, the latter increases Normal force exerted by the first clamping means on the brake pad until a normal force FLN _N sufficient for an emergency stop or the resulting braking force is made available. In the present case, a delivery is understood to mean, in particular, a movement of the brake lining, which already has frictional contact with the brake track, or a corresponding control means in such a way that the first clamping device is further tensioned.

According to an advantageous embodiment of the present invention according to claim 9, which is explained in the introduction, the braking device now comprises a first Zustellbegrenzungsmittel which locks a feed position of the brake pad in a first position and in a second position enables a feed movement of the brake pad. If the braking device to exercise a holding function, the first Zustellbegrenzungsmittel is switched to the first position. An advancing movement of the movable brake lining is effectively prevented by the delivery limiting means connected to the first position. This is preferably done actively by a power-supplied lock, so that in case of failure of this power supply, the first Zustellbegrenzungsmittel switches automatically or under the action of the feed movement of the movable brake pad in the second position. Alternatively, the body is coupled to the lock with a defined pushing-away force, so that automatically switches to a second position before slipping the pad, the lock.

In an emergency stop, the actuator and the lock are disabled while the elevator car moves or the lock disables itself, as the brake pad slips and exerts a corresponding pushing force on the automatically switching lock. The first clamping means moves the brake pad against the brake track, which delivers this under frictional engagement. As a result, the first tensioning means is tensioned so that the normal force exerted on the brake lining increases at least to a normal force FLN _N sufficient for an emergency stop.

At a floor stop, the actuator is deactivated while the elevator car is stationary while the lock is activated. The first clamping means in turn moves the brake pad against the brake track. However, the movable brake pad can not deliver due to the first Zustellbegrenzungsmittels located in its first position, so that the force exerted on it normal force is limited to a lower, sufficient for holding normal force FLN _H , or biasing force. Thus, between a floor stop and an emergency stop, the normal forces exerted by the first tensioning means on the movable brake pad differ by the normal force increase which the tensioning means additionally applies during the advancing movement of the movable brake pad.

Thus, a braking device according to the present invention exerts at a landing stop a lower normal force FLN _H on the movable brake pad and automatically provides a higher normal force FLN _N in an emergency stop according to the feed movement of the movable brake pad.

A brake device according to the invention and a brake track are therefore less heavily loaded during normal operation. In addition, the actuator can be designed for this lower normal force FLN _H out.

In a preferred, other embodiment of the present invention according to claim 2, the same advantages can be realized without the first Zustellbegrenzungsmittel, which reduces the construction and control effort and increases the reliability.

For this purpose, the braking device according to the first embodiment of the present invention instead of the first Zustellbegrenzungsmittels a multi-part brake pad, in particular a fixed brake pad and a movable brake pad, which are biased jointly by the first clamping means and released by the actuator, wherein advantageously the movable brake pad a second biasing means is biased against the braking track when the fixed brake pad comes into contact with the braking track. The multi-part brake pad acts on a common braking surface of the brake track.

If this braking device exercises a holding function, only the preload of the second clamping device acts on the movable brake lining. This is preferably selected to be relatively small, so that the majority of the force exerted by the first tensioning means when the actuator is deactivated acts as a normal force on the fixed brake lining. This normal force depends, inter alia, on the elasticity of the second tensioning means and on the gap between the released fixed brake pad and the brake track and can be selected accordingly. In any case, the design is designed such that a large part of the normal force acts on the fixed brake pad, whereby a maximum holding force can be achieved. Thus, on the other hand, when held at a floor stop, a minimum normal force acts without the movable brake pad being delivered - a movement of the brake device relative to the braking track necessary for this purpose is prevented by the frictional engagement of the fixed brake lining with the braking track.

In an emergency stop, however, comes the movable brake pad, which is biased by the second tensioning means and accordingly protrudes beyond the fixed brake pad, if this does not affect the brake track, first in contact with the brake track. As a result, it is delivered under frictional engagement with the brake track and clamps the first clamping means, whereby the normal force acting on the movable brake pad increases to a higher, sufficient for an emergency stop normal force FLN _N , force. Preferably, the fixed brake lining no longer comes into contact with the brake track, the power flow takes place exclusively via the movable brake pad. The emergency brake function is also guaranteed in a possible slipping out of a holding position, since the pressed with little force movable brake pad would be delivered as described with frictional engagement with the brake track.

Thus, a brake device according to this embodiment also exerts a lower normal force FLN _H on the fixed and movable brake pad and automatically provides a higher normal force FLN _N during an emergency stop according to the feed motion of the movable brake pad. As the normal force during holding is essentially absorbed by the fixed brake linings, the approximate total forward or normal force is available for holding.

Thus, in both embodiments, at a floor stop, i. when the actuator is deactivated when the elevator car is stationary, a feed movement of the movable brake pad and thus a sagging of the car and an increase in the normal forces acting on the brake track are prevented. This possibly unexpected slipping can be subsequently detected in case of need by means of a sensor or switch. This can also be a reliable statement on the security status of a braking device. For example, due to wear or hardening of the fixed brake lining, which is to effect the holding of the car in a floor, a holding ability leads to slipping of the cabin, which as described leads to a delivery of the movable brake pad and thus in turn to a hold. Since this can now be determined by means of the sensor or switch does not occur unsafe condition, as timely maintenance or repair of the braking device can be initialized.

Preferably, the braking device is arranged on the elevator car. The cabin is guided along rails, which are also used as braking track. Two or more braking devices are advantageously arranged in pairs, wherein in each case at least one braking device acts on a rail. This is advantageous because in this arrangement, the elevator car is held directly and thus no oscillations occur at the car even during loading and unloading operations. Alternatively or additionally, the braking device can also be arranged in the drive, in which case the braking track is defined by a brake disk or drum. The drive can be arranged separately in or outside the shaft and an operation of the Elevator car is then carried on suspension. The drive can of course also be done directly on the cabin or on the counterweight.
Of course, a relative movement between brake device and brake track can be different. Thus, the braking track can be mounted stationary and the braking device moves along the brake track or the braking device can be arranged stationary with the brake track or a brake disc then moves along the braking device.

In a further preferred embodiment of the present invention, the above-described embodiment according to claim 9 or the first embodiment according to claim 1 is developed so that they can fulfill not only the emergency stop but also a free-fall brake function. This is particularly advantageous when the braking device is arranged on the cabin.

For this purpose, this particularly preferred embodiment comprises a second Zustellbegrenzungsmittel limited in a first position, a feed movement of the movable brake pad and in a second position allows a further feed movement of the movable brake pad.

In an emergency stop situation, the second Zustellbegrenzungsmittel which is like the first Zustellbegrenzungsmittel preferably actively switched by a powered barrier, so that in case of failure of this energy supply Zustellbegrenzungsmittel automatically or under the action of the feed movement of the movable brake pad in the second position, switched to the first position in which the feed movement of the movable brake pad is limited to a certain maximum movement. As described above, as a result of frictional engagement with the rail, the movable brake pad automatically adjusts itself until the second delivery limiting means prevents it from further advancing movement. This predetermined by the second Zustellbegrenzungsmittel maximum feed movement limits the maximum occurring during an emergency stop normal force FLN _N , so that an excessive braking deceleration on the passengers and a correspondingly high load on the braking device, the rail and the elevator car can be avoided.

In a free-fall braking, however, higher braking forces must be applied and the associated burdens are accepted in order to crash the elevator car to prevent. Therefore, in a freefall braking the second Zustellbegrenzungsmittel is deactivated, so that the movable brake pad further deliver and so can tighten the first clamping means on. As a result, an increase in the normal force FLN _F acting on the movable brake pad and a corresponding increase in the braking force acting on the elevator car are automatically effected. The Zustellbegrenzungsmittel is preferably designed such that it can be deactivated even during braking, for example, if an insufficient delay in emergency stop would be detected. Thus, the normal force during braking in case of need can be further increased.
This second amplification stage allows a fine graded to the different braking situations braking force. Of course, a braking device without this second amplification stage can be used for a freefall braking, in which case there is a braking force surplus in emergency stop operation. This is a favorable design because no infeed limiting means are required and yet low biasing forces can be used to hold.

Preferably, the braking device comprises a third clamping means, which biases the movable brake pad against its advancing movement. This advantageously ensures that the movable brake pad is always in its undelivered position while driving. In an emergency stop or a free-fall braking, the movable brake pad can be delivered against the third clamping means, which is preferably formed correspondingly weak for this purpose.

Preferably, the rigidity of the first clamping means is progressive. Thus, the normal force increasing with a delivery of the movable brake lining increases more and more, so that in an emergency stop or a free-fall braking, in which a large feed movement occurs, particularly high braking forces are provided. On the other hand, only a relatively small actuator energy must be expended for releasing the brake pads, in which the first clamping means still has a lower rigidity.

For this purpose, the first clamping means may comprise a holding clamping means whose clamping path is limited, and a reinforcing clamping means whose rigidity is higher than that of the holding clamping means. Holding clamping means and reinforcing clamping means are preferably connected in series, so that first, for example, when a release of the brake pads, the actuator operates against the softer holding clamping means and this requires little energy. Is its tension travel used up, which is advantageously dimensioned so that it substantially corresponds to the gap between the brake pad and rail, so, for example, in a feed movement of the movable brake pad, now only the stiffer reinforcing clamping means are stretched, which increases the normal force for the emergency stop and the free-fall , Of course, the reinforcing clamping means can also be integrated directly into components of the braking device, for example by making brake calipers correspondingly elastically resilient.

In order to realize the advancing movement of the movable brake lining, it can be mounted on the brake caliper via a wedge surface, which is acted on by the first tensioning means and the actuator, wherein the wedge surface effects the advancing movement of the movable brake lining. If the movable brake pad follows the relative movement of the brake track with respect to the brake device under frictional engagement, then the wedge surface simultaneously forces the brake caliper to move out perpendicular to the stroke movement of the movable brake pad. This Ausrückweg can be used to tension the first clamping means.

In another embodiment of the present invention according to claim 7, the brake pad is mounted on the brake caliper via an eccentric disc, so that the eccentric disc effects the advancing movement of the brake pad. Follows the eccentric disc, for example by means of cam, frictionally the relative movement of the brake track relative to the braking device, the eccentric rotates with the lifting movement of the movable brake pad and thereby changes the distance of the movable brake pad relative to the pivot point of the eccentric disc. This change in distance can be used for clamping the first clamping means.
Advantageously, the eccentric disc has an area of low rigidity. Thus, a large part of the acting biasing force is guided over the brake pad and a holding force can be obtained with minimal preload force.

Preferably, the braking device according to the invention comprises two brake circuits, each of which has a movable brake pad and a first Zustellbegrenzungsmittel and / or an undeliverable brake pad. The two brake circuits act on a brake track with two braking surfaces, which braking surfaces are advantageously formed by opposing surfaces of a rail web. The two brake circuits can thus pinch the brake track or the rail bar. The deliverable brake pads both Brake circuits can be acted upon by their own first clamping devices and actuators. Advantageously, however, the movable brake pads of both brake circuits are acted upon by a common first clamping means and a common actuator, which advantageously reduces the construction costs and space requirements.
Alternatively, of course, only one of the brake circuits can be equipped with a movable brake pad and a Zustellbegrenzungsmittel and / or an undeliverable brake pad, while the other brake circuit is designed with a fixed brake pad.

The movable brake pads of the two brake circuits can deliver automatically at the same or different directions of travel of the elevator car relative to the rail.

Adjust the brake pads at different traversing directions, so the Bremskrafterhöhung can act in both directions, advantageously different delivery routes and thus different braking force increases can be displayed. If, for example, the elevator car is partially balanced, different emergency brake loads can occur if the suspension element is intact, depending on the cabin load. Conversely, the braking force increase in one direction can be increased if both movable brake pads deliver in the same direction of travel.

• Fig. 1 eine Hälfte der Bremseinrichtung nach Fig. 3 im gelüfteten Zustand;
• Fig. 2 die Hälfte der Bremseinrichtung nach Fig. 3 bei einem Stockwerkshalt;
• Fig. 3 eine Bremseinrichtung nach einer ersten Ausführung der vorliegenden Erfindung bei einem Notstop;
• Fig. 4 die Hälfte der Bremseinrichtung nach Fig. 3 bei einer Freifallbremsung; und
• Fig. 5 eine Bremseinrichtung nach einer weiteren Ausführung der vorliegenden Erfindung mit Bremspositionen Fig. 5A bis 5D .

Other objects, advantages and features will become apparent from the dependent claims and the embodiments described below. This shows, partially schematized:

• Fig. 1 one half of the braking device after Fig. 3 in the ventilated state;
• Fig. 2 half of the braking device after Fig. 3 at a floor stop;
• Fig. 3 a braking device according to a first embodiment of the present invention in an emergency stop;
• Fig. 4 half of the braking device after Fig. 3 in a freefall braking; and
• Fig. 5 a braking device according to another embodiment of the present invention with braking positions Figs. 5A to 5D ,

The FIGS. 1 to 4 show a holding and emergency stop braking device according to a first embodiment of the present invention. It shows Fig. 3 the two brake circuits comprehensive

Braking device as a whole. Since both brake circuits are identical except for differences explained below, is in the Fig. 1, 2 and 4 only the left brake circuit is shown to explain the various brake situations - the function of the right brake circuit is basically analog. Equivalent parts are provided in the figures with the same reference numerals.

As in particular in Fig. 3 each brake circuit of the braking device according to the preferred embodiment of the present invention comprises a brake caliper 10 which is rotatably mounted on a pin 11. A holding clamping means in the form of a first compression spring 3.1 elastically biases both brake calipers 10 against a guide rail 1, to which an elevator car (not shown), to which the braking device is attached, can move vertically. The guide rail (1) has two braking surfaces (1a, 1b). An actuator in the form of an electromagnet 4 can ventilate the brake calipers 10 against the voltage of the first compression spring 3.1 and serves in this example simultaneously as a stop, ie limits the tension of the first compression spring 3.1.

At each brake caliper 10, a brake wedge holder 13 is slidably guided against the rail 1 and elastically mounted in this direction by a Verstärkungsspannmittel in the form of a fourth compression spring 3.2, which has a higher spring stiffness than the first compression spring 3.1. The first and fourth compression springs 3.1, 3.2 together with the brake caliper 10 form a tensioning means chain or a first tensioning means 3.

In the brake wedge holder 13, a brake wedge 12 can move in the direction of the relative movement between the elevator car and the rail between two stops and is forcibly guided by a wedge surface 9. In the left brake circuit, the wedge surface 9 is oriented so that the brake wedge 12 presses the brake wedge holder 13 against the fourth compression spring 3.2 when it moves relative to the brake wedge holder 13 upwards. In the right brake circuit of the brake wedge presses the brake wedge recording, however, against the fourth compression spring when it moves relative to the brake wedge holder 13 down.

A third clamping means in the form of a relatively weak third compression spring 8 ties the brake wedge 12 in the brake wedge holder 13 in its lowermost (left brake circuit) or uppermost (right brake circuit), by the one stop limited initial position. In addition, in this example, a second Zustellbegrenzungsmittel 7 is provided in the form of a wedge 7.1, the under the force of an activated lock in the form of a further electromagnet 7.2 protrudes into the wedge surface 9 and limits a movement of the brake wedge 12 along the wedge surface 9. If the additional solenoid 7.2 is activated, it presses the wedge 7.1 far enough into the wedge surface that the brake wedge 12 moves out of its initial position (FIG. Fig. 1, 2 ) only up to one in Fig. 3 shown center position can proceed. If the further solenoid 7.2 is deactivated, then the brake wedge 12 can displace the wedge 7.1 from the wedge surface 9 and into its in Fig. 4 moved shown upper (left brake circuit) end position. The brake wedge of the right brake circuit remains in the illustrated example in its upper position, since it holds the relative travel direction of the rail to the braking device in this position.

In the example shown, the left brake circuit has a long wedge surface 9. This results in a correspondingly large delivery option and a correspondingly large clamping possibility of the clamping elements 3, resulting in a correspondingly high maximum normal force FLN _{F can} result when the left brake wedge 12 reaches its upper end position. The right brake circuit, in contrast, has a shorter wedge surface. As a result, the maximum achievable normal force is smaller when the relative travel direction of the rail to the braking device is reversed. As a result, the force levels can be designed depending on the direction of travel.

In the brake wedge 12, a movable brake pad 2 is slidably guided against the rail 1 and elastically supported in this direction by a second clamping means in the form of a second compression spring 6, which has a low spring stiffness.

In addition to the stops that limit the movement of the brake wedge 12, fixed brake pads 5 are arranged on the brake wedge holder 13 so that they are slightly set back against the contact surface of the movable brake pad 2 with the rail 1 when the second compression spring 6 is relaxed.

The function of the braking device according to the first embodiment of the present invention will now be explained in more detail with reference to the figures 1 to 4.

Aired brake

Fig. 1 shows the left brake circuit of the braking device in the released or deactivated state. For this purpose, the electromagnet 4 is supplied with energy, pulls the brake caliper 10 against its acting as a stop left end face and thereby biases the first compression spring 3.1 maximum. The displacement of the brake caliper 10 to the rail 1 is dimensioned so that in the released state of the movable brake pad 2 and the fixed brake pads 5, the rail 1 and the braking surface 1 a do not touch. Therefore, the second compression spring 6 is relaxed and placed the movable brake pad 2 in its from the brake wedge 12 furthest protruding initial position. The third compression spring 8 is also relaxed, so that the brake wedge 12 is placed in its lowest initial position. The fourth, in comparison rigid, compression spring 3.2 is relaxed, since no forces act on the brake wedge holder 13.

In this released state, the electromagnet 4 must be supplied with only enough energy to maximally tension the first compression spring 3.1. In particular, therefore, he does not have to work against the fourth compression spring 3.2. The elevator car and the brake device attached thereto can move vertically unhindered relative to the rail 1.

Floor stop

Fig. 2 shows the left brake circuit of the braking device at a floor stop. After the elevator car has been brought to a halt by means of a suspension element from a drive unit (not shown) at floor level, the electromagnet 4 is deactivated. As a result, the first compression spring 3.1 partially relaxes and presses on the brake caliper 10, which consequently rotates about the pin 11. First, the movable brake pad 2 comes into contact with the rail 1. Since the second compression spring 6 is relatively weak, it is under the action of the first compression spring 3.1, the brake caliper 10 continues to rotate around the pin 11 against the rail 1, as long stretched until the fixed brake pads 5 come into contact with the rail. The brake caliper 10 continues to rotate until the fourth compression spring 3.2 is stretched so far that it exerts an equally large counter torque to the spring force of the first compression spring 3.1.

The first compression spring 3.1 is biased so that it exerts even in this position, a spring force F1 on the lying above the pin 11 lever arm of the brake caliper 10. Accordingly, the lever arm of the brake caliper 10 located below the bolt 11 exerts a force F2 on the fourth compression spring 3.2. Since the ratio i between upper and lower lever arm of the brake caliper greater than 1 is selected, this translation increases the force exerted by the first compression spring 3.1 on the second compression spring 3.2 force F2 = i × F1> F1. Advantageously, therefore, the electromagnet 4 must apply only a relatively small force to maximally tension the preloaded first compression spring 3.1 and so to ventilate the braking device.

On the movable brake pad 2 acts a normal force N1, which results from the clamping path s of the second compression spring 6 until the fixed brake pads 5 contact the rail 1. Since the spring stiffness c6 of the second compression spring 6 is chosen to be relatively low, this normal force N 1 = c6 × s is also relatively low.

Therefore, acts in the fixed brake pads 5, a normal force FLN _H , which corresponds to the substantial proportion of the force exerted by the second compression spring 3.2 on the wedge seat 13 force F2: FLN _H = F2 - N 1 ≈ i × F 1.

auf die Bremszange 10 ausübt. Dabei bezeichnet µ den Haftreibungskoeffizienten zwischen Schiene 1 und festen Bremsbelägen 5. In Gleichung (1) sind zur besseren Übersichtlichkeit Sicherheitsfaktoren vernachlässigt.In the exemplary embodiment, the elevator car is held at a floor stop of two identical braking devices according to the preferred embodiment of the present invention, so that the weight G of the elevator car, or the differential force between the counterweight and the car, each to a quarter on the fixed brake pads 5 a brake circuit a braking device distributed. The bias of the first compression spring 3.1 is now chosen so that these in the holding position a spring force $$\mathrm{F}\mathrm{1}\mathrm{=}\mathrm{1}\mathrm{/}\mathrm{i}\mathrm{\times }\left[\mathrm{G}\mathrm{/}\left(\mathrm{4}\mathrm{\mu }\right)\mathrm{+}\mathrm{c}\mathrm{6}\mathrm{\times }\mathrm{s}\right]$$

on the brake caliper 10 exerts. In this case, μ denotes the static friction coefficient between rail 1 and fixed brake linings 5. In equation (1), safety factors are neglected for the sake of clarity.

The elevator car is thus held at a regular floor stop substantially on the frictional engagement between the fixed brake pads 5 and the rail 1 and the movable brake pad remains in his in Fig. 2 shown initial position.

Without the fixed brake pads 5, the total weight G would be supported only on the movable brake pads 2 on the rail 1. Since in the wedge surface 9 only one Normal force N3 = cos (wedge angle) × F2 <F2 acts and also the coefficient of friction in the wedge surface is relatively small, to ensure easy displaceability of the brake wedge 12 in the brake wedge holder 13, the brake wedge 12 under the effect of the above-described spring force F1 gem , Eq. (1) come to slide on the wedge surface 9, which would cause a sagging of the elevator car at a hold of the braking device at a floor stop until the delivery described in more detail below leads to a sufficient increase in the normal force N3. Alternatively, a correspondingly higher bias of the first compression spring 3.1 would have to be provided in order to increase F2 = i × F1 accordingly. Then, however, the electromagnet 4 would have to apply a correspondingly higher energy in the released state in order to keep this force in balance.

In a second embodiment of the present invention, not shown, a first Zustellbegrenzungsmittel is provided in place of the fixed brake pads 5, which is functionally identical to the second Zustellbegrenzungsmittel 7. This first infeed limiting means completely blocks movement of the brake wedge 12 along the wedge surface 9, i. sets the brake wedge 12 in its initial position. With the first Zustellbegrenzungsmittel activated, the movable brake pad 2, which can now no longer deliver by the method of the brake wedge 12 along the wedge surface 9, like a fixed brake pad, so that, as described above with respect to the first embodiment, a sagging of the elevator car at a floor stop or a high bias of the first compression spring 3.1 can be avoided.

emergency stop

Fig. 3 shows the braking device in an emergency stop. As explained above, the elevator car in the exemplary embodiment has two identical brake devices according to the first embodiment of the present invention, of which, for example, each act on both sides of the car arranged guide rails 1. In an emergency stop, the elevator car should be able to be braked to a standstill with intact suspension by the braking device, for example, if the engine brake of the drive unit fails or there is a control defect. In addition, it is required for safety reasons that even if one of the brake devices fails, the remaining brake device at least does not further accelerate, even in an overload condition.

In the present case (with two brake devices), therefore, each braking device alone must be able to support the overweighting force Ü of the elevator car. Accordingly, each brake circuit must exert a significantly higher frictional force on the rail 1 in relation to the above-described holding at a floor stop. With an overload condition of 125% of the normal load and a weight difference of 50% of the normal load between the counterweight and the cab, there is thus the requirement for a factor of three increased braking force and thus a correspondingly increased normal force.

When emergency stop, starting from the released state after Fig. 1 , the solenoid 4 deactivated while the elevator car along the rail 1 moves. As a result, the first compression spring 3.1 rotates the caliper 10 about the pin 11 against the rail 1. Here, first, the movable brake pad 2, which is biased by the second compression spring 6, in frictional contact with the rail first

The normal force generated by the second compression spring 6 causes a force acting on the movable brake lining friction, which seeks to take this in the direction of the relative movement of the braking device relative to the rail 1. If, for example, the elevator car moves vertically downwards, the movable brake lining 2 is displaced upward. He takes the brake wedge 12, which slides on the wedge surface 9 upwards.

Due to the wedge effect of the brake wedge 12 while the brake wedge holder 13 to the outside. This prevents on the one hand that the fixed brake pads 5 still come into contact with the rail 1 - the frictional engagement continues exclusively via the movable brake lining 2. On the other hand, the outwardly wandering brake wedge holder 13 tensions the fourth compression spring 3.2 and thus via the brake caliper 10 also the first compression spring 3.1. As a result, the brake caliper 10 is against the force of the first compression spring 3.1 back, while the first and fourth compression spring 3.1, 3.2 and depending on the design of the elastic brake caliper 10 comprehensive first clamping means 3 is stretched. By this feed movement of the movable brake pad 2, ie its stroke in the rail direction, so the first clamping means 3 is additionally tensioned, so that increases the force exerted by him on the movable brake pad 2 normal force and thus the braking force of the braking device.

The brake caliper 10 runs against the stop formed by the end face of the electromagnet 4, which prevents further compression of the first compression spring 3.1. Shifts now the movable brake pad 2 with the brake wedge 12 further up and presses the brake wedge holder 13 further outward, so only the fourth, stiffer compression spring 3.2, or defined by the brake caliper 10 or other components of the braking device spring stiffness, further excited. By this switching from the series-arranged first, softer and fourth, harder compression spring 3.1, 3.2 exclusively to the fourth compression spring 3.2, the rigidity of the first clamping means 3 increases progressively.

In an emergency stop the additional solenoid 7.2 of the second Zustellbegrenzungsmittels 7 is activated. This presses the wedge 7.1 in the wedge surface 9, which limits the displacement of the brake wedge 12 along the wedge surface 9 and stops the movable brake pad 2 in the center position.

In this middle position, the left brake circuit exerts a higher normal force on the rail 1 than is the case with a hold at a floor stop, in which the electromagnet is deactivated after the elevator car has come to a standstill: on the one hand, the movable brake lining 2 is established under frictional engagement with the rail 1 and thereby clamps the first clamping means 3 more than at a floor stop. The additional tensioning path can be specified by the choice of the wedge angle and / or its length. On the other hand, the stiffness of the first clamping means 3 jumps to a significantly higher value as soon as the brake caliper 10 strikes the electromagnet 4 and the first compression spring 3.1 can not be further compressed. The further delivery is completely implemented in the compression of the stiffer fourth compression spring 3.2. It goes without saying that the wedge angle must be chosen taking into account the expected coefficient of friction, so that an independent delivery is guaranteed.

The movable brake pad 2 thus adjusts itself to a frictional engagement with the rail 1 during a movement of the elevator car relative to the rail automatically and thereby tensions the first chip means 3, so that the normal force acting on the movable brake pad and thus the frictional force applied by the brake device increases , Nevertheless, the electromagnet 4 only has to apply a relatively small amount of energy to the braking device ventilate, as this only the first compression spring 3.1 must be stretched maximum. It is self-evident that the delivered movable brake pad is first moved in the direction of its normal position, which is defined for example by spring 8, before the brake device is released. This can be achieved by moving the brake device in a brake opposite direction. It should be noted that a left-side and an opposite right wedge surface, as in Fig. 3 shown, in the length of which are coordinated with each other, that in each case an air gap at the actuator 4 is formed when the braking device is moved in the opposite direction of braking.

The fixed brake pads 5, which are biased together with the movable brake pad 2 by the first clamping means 3 and released by the electromagnet 4, get in contact with the rail 1 only when the electromagnet 4 is deactivated when the elevator car is stationary, since the movable brake pad 2 is biased by the second compression spring 6 against the rail 1 and comes in contact with the rail 1 in front of the fixed brake pads 5. They prevent sagging of the elevator car in the case of a floor stop, but are inoperable in the event of an emergency stop, so that the movable brake lining 2 is delivered and thus increases the braking force to the value limited by the second delivery limiting device 7. When using the in Fig. 3 shown braking device are loaded at a floor stop only the fixed brake pads substantially, wherein at an emergency stop or free fall the braking force on one side via the movable brake pads and on the opposite side on the fixed brake pads are initiated. This results from the opposite execution of the wedge surface.

As in Fig. 3 recognizable, the movable brake pads 2 of the two brake circuits with different travel direction of the elevator car relative to the rail automatically: due to the opposite inclined wedge surfaces, the movable brake lining of the left brake circuit increases when the elevator car is braked during a downward travel, while the movable Brake pad of the right brake circuit is delivered when an emergency stop occurs during an upward movement of the elevator car. By different dimensioning of the two brake circuits, in particular the wedge angle and / or wedge surface lengths and the stiffnesses of the fourth compression spring, different brake force gains can be specified for the up and down direction, which is particularly advantageous in partially balanced lifts in which the over the intact suspension means with a counterweight connected elevator car in case of failure of Drive unit is pulled up or slips down. Alternatively, both brake circuits can deliver relative to the rail even in the same direction of travel of the elevator car and thus increase the braking force particularly strong in an emergency stop in a direction of movement.

Another advantage of the present invention is found when the frictional force between rail 1 and fixed brake pad 5 is erroneously too low because, for example, the fixed brake pad or rail is worn or soiled, so that the friction coefficient decreases. If the frictional force applied via the fixed brake pad 5 is insufficient in the case of a floor stop, then as described above, the elevator car will sag a little. As a result, the movable brake lining 2 continues to increase until the tension of the first clamping device 3, which is increased by its delivery, becomes so great that a sufficient frictional force is generated. In this respect, the present invention provides a safety-redundant braking device that automatically adjusts itself to faulty low frictional force at a floor stop until a sufficient frictional force is present to keep the elevator car safely. This feed movement could be detected by a sensor, whereby a sagging in the hold could be detected and appropriate maintenance could be initialized.

Free fall stunt

Fig. 4 shows the braking device in a freefall braking. Essentially, this runs like the emergency stop described above. However, since the suspension element is defective in a freefall braking and the elevator car is no longer at least partially braked by a counterweight and an internal friction of a drive unit, here the braking device must apply an even higher braking force.

For this purpose, the second Zustellbegrenzungsmittel 7 is deactivated by the other solenoid 7.2 is not supplied with energy. As with the emergency stop comes when deactivation of the electromagnet 4, first, the movable brake pad 2 in frictional contact with the rail 1, is taken from this and put it to. This increases the force acting in frictional contact between the movable brake pad and rail normal force and, accordingly, the braking force. Since the wedge 7.1 is no longer locked by the further electromagnet 7.2, the brake wedge 12 presses it out of the Wedge surface 9 down and can drive up to a top (left brake circuit) end position where it is stopped by the other of the two stops in the brake wedge holder 13.

As a result, the feed path of the movable brake pad 2, with which the fourth compression spring 3.2 is tensioned, increases beyond the value achieved during an emergency stop, in which the feed movement is stopped by the second feed limiting means 7 in the middle position. Accordingly, the force exerted by the fourth compression spring 3.2 normal force and thus the force acting on the rail 1 braking force increases.

Advantageously, this maximum braking force is achieved only in a freefall braking, while the activated second Zustellbegrenzungsmittel limits the braking force in an emergency stop to a lower value and thus unnecessarily high loads on the guide rail 1, the elevator car, the braking device and the passenger avoids.

Since a free fall can only take place in the downward direction, generally only one side of the braking device (in the example shown, the left side) is equipped with a corresponding feed stroke and the other side has a correspondingly reduced feed stroke. Of course, however, further delivery delimiting means may be used to define intermediate braking values.

Preferably limit stops the adjustment of the movable brake pad 2 relative to the brake wedge 12 in order to avoid overloading of the second compression spring 6.
The Zustellbegrenzungsmittel 7 may be equipped in place of the electromagnets 7.2 with a spring grid system, which allows a Wegdrücken the Zustellbegrenzungsmittels when a definable holding force is exceeded.

Alternative design

The FIGS. 5A to 5D show an alternative delivery of the movable brake lining 2 by an eccentric disc 12 'in the various braking situations "ventilated" ( Fig. 5A ), "Floor stop" ( Fig. 5B ), "Braking downwards" ( Fig. 5C ) or "braking downwards" ( Fig. 5D ).

The braking device with this alternative delivery corresponds in its basic structure of the first embodiment described above, so that only the differences from the first embodiment will be discussed below.

In the case of the braking device with the alternative infeed, the movable brake pad 2 'is guided on an eccentric disk 12', which is mounted rotatably about a pin 14 on an eccentric mount 13 '. The eccentric receptacle 13 'corresponds to the extent of the brake wedge receptacle 13 of the first embodiment, so that the subsequent construction with the first clamping means, actuator and the like is not shown.

The eccentric 12 'is compared to the eccentric 13' by a Zentrierfederfeder or a grid (not shown) elastically tied and is by this centering spring or the grid in the in Fig. 5A biased position shown, so that the movable brake pad 2 'at the same time the function of the fixed brake pad 5' takes over the contact plane of a fixed to the eccentric 12 'connected control disc 12'a protrudes when the braking device is released ( Fig. 5A ). A second brake circuit advantageously consists of a fixed brake pad 5, which in a manner already shown by compression spring 3.2 and pliers 10 connected to a first clamping means, actuator and the like.

In the case of a floor stop, when the elevator car is stationary, the eccentric receptacle 13 'is pressed against the rail 1 via the brake caliper (not shown) like the brake wedge receptacle 13 of the first embodiment by the first compression spring, by deactivating the electromagnet. Here, an elastic region 6 'of the control disk 12'a pushed back so far that the brake pad 2', 5 'touch the rail 1 and frictionally transmitted the essential portion of the braking force to this. ( Fig. 5B ).

If the solenoid is deactivated in an emergency stop, while the elevator car moves relative to the guide rail 1, so again the eccentric 13 'is moved against the rail 1. In this case, the control disk 12'a first comes into frictional contact with the rail 1 and is carried along by it, the eccentric disk 12 'being rotated on the journal 14 with respect to the eccentric receiver 13'. As a result, the brake pad 2 ', 5' turns and tensions the first tensioning means, since the eccentric receptacle 13 'is forced outwards in a form-fitting manner ( Fig. 5C, Fig. 5D ). The shape of the cam 12'a in this case defines a rotational angle to be traversed, since the control cam is rotated so far frictionally until the eccentric disc has the brake pad 2 ', 5' delivered to the rail so far that this takes over a major part of the normal force. The cam is advantageously provided with Reibunterstützender surface, for example, roughened and hardened. The elastic region 6 'of the control disk 12'a is designed according to the invention such that during a relative movement of the braking device to the rail 1, the control cam is rotated, but on the other hand when holding in a floor of the substantial part of the normal force from the brake pad 2', 5 'is taken ,

By clamping by means of control cam and eccentric disc and the outward urging of the eccentric 13 'increases the force acting on the movable brake pad 2 normal force, so that the frictional force or braking force, which now essentially over the rail 1 touching brake pad 2', 5 'is increased to the extent that a sufficient for an emergency stop value is reached.

Depending on the direction of travel (upwards or downwards), the control cam 12'a together with the eccentric disk 12 'defines the tensioning of the braking device. For example, when braking down, as in Fig. 5C shown, the brake device stretched wide and built up a correspondingly high braking force. Thus, a free fall of the elevator car can be secured. When braking up, as in Fig. 5D it can be seen that the braking device is relatively less tensioned by the control cam 12'a rotating in the reverse direction, whereby a correspondingly lower braking force is established.

Also in this embodiment, a feed movement by means of a Zustellbegrenzungsmittels be limited occasionally by the rotational movement of the Excenters is limited by a switchable lock. Attention should be paid to a careful coordination of the control cam with the Excenters. Optionally, the cam is in the areas of rotation limitation, or at the place where the cam is in the rotation limiting the rail in contact, also elastic perform. The braking device shown is shown using the example of a use as a car brake. However, this device is also executable as part of the drive. Likewise, it can be placed on the counterweight. Furthermore, at the Examples only spoken of coefficient of friction. Of course, the interpretation can also take into account differences between static friction and Gleitreibwert.

Claims (16)

Braking device for holding and braking an elevator car in an elevator installation, the braking device is arranged movable relative to a brake track (1) along this brake track (1) in two traversing directions,
the brake device comprises a receptacle (13) with a brake pad (2, 5), and a first tensioning means (3),
the receptacle (13) with the brake lining (2, 5) can be ventilated by an actuator (4),
in unventilated, activated state of the braking device, the first clamping means (3) biases the receptacle (13) and the brake pad (2, 5) with a prestressing force against the braking track (1), wherein when the braking device is stationary, the brake pad (2, 5) generates a holding force acting in both directions of travel, which holding force is essentially defined by the prestressing force,
characterized in that
in unventilated, activated state of the braking device and a subsequent relative movement of the braking device in at least one of the traversing directions, a part of the brake pad (2, 5), the first clamping means (3) and thus on the receptacle (13) and the brake pad (2, 5) acting clamping force, automatically tensions and thus generates a counter to the direction of travel of the braking device directed braking force, which braking force is essentially defined by this tensioned clamping force. Braking device according to claim 1, characterized in that
the brake pad (2, 5) is in several parts, wherein the multi-part brake pad (2, 5) on a common braking surface (1a) of the brake track (1) can act and
the multi-part brake pad (2, 5) arranged in the receptacle (13) comprises a fixed brake pad (5) and a movable brake pad (2), wherein the fixed brake pad (5) together with the movable brake pad (2) is supported by the first cocking means (2). 3) can be prestressed and ventilated by the actuator (4). Braking device according to claim 2, characterized in that a majority of the holding force defined by the prestressing force acts on the fixed brake pad (5) when the brake device is stationary, and in that a large part of the braking force defined by the tensioned clamping force acts on the moving brake device Brake pad (52) acts. Braking device according to claim 2 or 3, characterized in that the movable brake pad (2) by a second clamping means (6) is biased against the brake track (1) when the fixed brake pad (5) in contact with the braking track (1). Braking device according to one of claims 2 to 4, characterized in that it further comprises a third clamping means (8) which biases the movable brake pad (2) against its advancing movement. Braking device according to one of claims 2 to 5, characterized in that the movable brake pad (2) via a wedge surface (9) in the receptacle (13) which is actuated by the actuator (4) is mounted, wherein the wedge surface (9 ), in a relative movement between the brake device and brake track (1), the feed movement of the movable brake pad (2) causes. Braking device according to claim 1, characterized in that the brake pad (2, 5) via an eccentric disc (12 ') in the receptacle (13) is mounted, which is acted upon by the first clamping means (3) and the actuator (4), wherein the eccentric disc (12 '), upon movement of the braking device relative to the brake track, the feed movement of the brake pad (2, 5) causes. Braking device according to claim 7, characterized in that the eccentric disc (12 ') has a region of lower rigidity (6). Braking device according to one of the preceding claims, characterized in that the braking device further comprises a first Zustellbegrenzungsmittel which in a first position, a feed movement of the brake pad (2, 5) blocks and in a second position, a feed movement of the brake lining (2, 5). Braking device according to claim 9, characterized in that it comprises a second Zustellbegrenzungsmittel (7) which in a first position (Fig 1-3, 5A-5C) limits a feed movement of the movable brake pad (2) and in a second position (Fig 4; Fig. 5D) enables a feed movement of the movable brake lining (2). Braking device according to one of the preceding claims, characterized in that the rigidity of the first clamping means (3) is progressive. Braking device according to one of the preceding claims, characterized in that it comprises two brake circuits, which are actuated by the actuator (4) and the first clamping means (3), of which both brake circuits each have an undeliverable brake lining (2, 5) or of which a brake circuit has an undeliverable brake pad (2, 5) and the other brake circuit has only one fixed brake pad (5). Braking device according to claim 12, characterized in that the deliverable brake linings of the two brake circuits automatically determine the same or different traversing directions of the braking device relative to the braking track. Braking device according to one of the preceding claims, characterized in that the braking device is arranged in a drive unit and the brake track is one, preferably integrally connected to a traction sheave of the drive unit, brake disc or brake drum is executed, the two Verfahrrichtungen by the radial forward or reverse rotation of Brake disc or the brake drum are determined. Braking device according to one of claims 1 to 13, characterized in that the braking device, preferably in a pair arrangement, is arranged on the elevator car, wherein the braking track is a guide rail of the elevator car, and the two traversing directions by the substantially vertical upward or downward movement of the Elevator car are determined. Method for holding and braking an elevator car in an elevator installation, by means of a braking device which is arranged movable relative to a brake track (1) along this brake track (1) in two travel directions,
which brake device contains a receptacle (13) with a brake pad (2, 5), wherein the receptacle (13) with the brake pad (2, 5) can be released by an actuator (4),
which brake device further contains a first tensioning means (3), wherein in the unventilated, activated state of the braking device, the receptacle (13) and the brake pad (2, 5) by the first tensioning means (3) with a prestressing force against the braking track (1) be biased whereby a braking force acting in both of the traversing directions is generated when the braking device is stationary, characterized in that
by a following relative movement of the braking device in at least one of the traversing directions, at least by a part of the brake pad (2, 5), the first tensioning means (3), and thus acting on the receptacle (13) and the brake lining (2, 5) Clamping force, is automatically re-tensioned,

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