Elevator braking method

Abstract

In an elevator installation an elevator cage is movable along at least two guide rails and the elevator cage is equipped with a braking system. An elevator braking device includes a brake element, a force store, which is constructed to press the brake element against the brake surface, and an actuator, which can act on the brake element. A method of operating the braking device includes the actuator pressing, in a first operational setting, the brake element against the force of the force store away from the brake surface or to hold it at a spacing therefrom, and the actuator freeing, in a second operational setting, the brake element and allowing the force store to press the brake element against the brake surface.

Claims

1. An elevator braking method, comprising the steps of: deactivating an actuator of an elevator braking device and freeing a brake element of the elevator braking device; pressing the brake element of the elevator braking device against a brake surface using a force store; and moving the brake element initiated by a relative movement between the elevator braking device and the brake surface and thereby moving the actuator in a reset position corresponding with an operational setting of the actuator.

2. The elevator braking method according to claim 1, the brake surface being on a guide rail.

3. An elevator braking method for an elevator brake device including a brake housing, a brake element arranged in the brake housing by a rotary bearing and including a curved surface such that a radial spacing from the rotary bearing to the curved surface increases over a rotational angle, a force store that can press the brake element against a brake surface, and an actuator that can act on the brake element, the method comprising the steps of: in a first operational setting of the brake device, urging the brake element against the force store and away from the brake surface; in a second operational setting of the brake device, freeing the brake element and allowing the force store to press the brake element against the brake surface; and moving the actuator into a reset position corresponding with the first operational setting as a result of the brake element being pressed against the brake surface and being entrained by a relative movement between the elevator braking device and the brake surface and thereby moving the actuator into the reset position.

4. The elevator braking method according to claim 3, the brake surface being part of a rail guide.

5. The elevator braking method according to claim 3, the brake element being incorporated into the brake housing, the force store and the actuator being configured to act on the brake element using the brake housing.

6. The elevator braking method according to claim 5, the brake housing being mounted and being horizontally displaceable in a support, the actuator being mounted in the support.

7. The elevator braking method according to claim 3, the curved surface comprising a center clamping region, the center clamping region being eccentrically shaped relative to the rotary bearing.

8. The elevator braking method according to claim 7, the brake element further comprising a first braking region connected with the center clamping region.

9. The elevator braking method according to claim 8, the brake element further comprising a second braking region connected with an end of the center clamping region opposite the first braking region.

10. The elevator braking method according to claim 3, the brake element comprising a control eccentric, the control eccentric comprising the curved surface.

11. The elevator braking method according to claim 3, further comprising a brake plate positioned to engage the brake surface or a guide rail opposite the brake element.

12. The elevator braking method according to claim 11, further comprising a brake spring coupling the brake plate and the brake housing.

13. The elevator braking method according to claim 3, the actuator comprising a clamping electromagnet with an armature plate, wherein in the first operational setting the armature plate bears against and is electromagnetically held by the clamping electromagnet, wherein the armature plate, when the actuator is brought into the reset position corresponding with the first operational setting, contacts the clamping electromagnet in a current-free state of the clamping electromagnet.

14. The elevator braking method according to claim 13, the actuator being settable to enable setting of the first operational setting.

15. The elevator braking method according to claim 3, the actuator comprising an assisting weight, the assisting weight holding an entrainer in contact with the brake element or the brake housing.

16. The elevator braking method according to claim 5, the entrainer comprising a blocking roller.

17. The elevator braking method according to claim 3, the actuator comprising an assisting spring, the assisting spring holding an entrainer in contact with the brake element or the brake housing.

18. The elevator braking method according to claim 17, the entrainer comprising a blocking roller.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The disclosure is explained using the figures, in which:

(2) FIG. 1 shows a schematic view of the elevator installation in side view;

(3) FIG. 2 shows a schematic view of the elevator installation in cross-section;

(4) FIG. 3 shows a schematic view of an elevator braking device in a first operational setting;

(5) FIG. 4 shows the elevator braking device of FIG. 3 in a second operational setting;

(6) FIG. 5 shows the elevator braking device of FIG. 3 in a reset position corresponding with the first operational setting;

(7) FIG. 6 shows the elevator braking device of FIG. 3 in a clamping setting;

(8) FIG. 7 shows the elevator braking device of FIG. 3 in a braking setting;

(9) FIG. 8 shows a perspective view of a realized elevator braking device;

(10) FIG. 9 shows a back view of the brake of FIG. 8 in the first operational setting;

(11) FIG. 10 shows a plan view of the brake of FIG. 8 in the first operational setting;

(12) FIG. 11 shows a back view of the brake of FIG. 8 in the second operational setting;

(13) FIG. 12 shows a plan view of the brake of FIG. 8 in the second operational setting;

(14) FIG. 13 shows a back view of the brake of FIG. 8 in the braking setting; and

(15) FIG. 14 shows a plan view of the brake of FIG. 8 in the braking setting.

(16) In the figures the same reference numerals are used in all figures for equivalent parts.

DETAILED DESCRIPTION

(17) FIG. 1 shows an elevator installation 1 in an overall view. The elevator installation 1 is installed in a building and serves for the transport of persons or goods within the building. The elevator installation includes an elevator cage 2, which can move upwardly and downwardly along guide rails 6. The elevator cage 2 is for that purpose provided with guide shoes 8, which guide the elevator cage, possibly precisely as possible along a predetermined travel path. The elevator cage 2 is accessible from the building by way of doors. A drive 5 serves for driving and holding the elevator cage 2. The drive 5 is arranged in, for example, the upper region of the building and the cage hangs at the drive 5 by support means 4, for example support cables or support belts. The support means are guided by way of the drive 5 onward to a counterweight 3. The counterweight compensates for a mass component of the elevator cage 2 so that the drive 5 primarily merely has to compensate for an imbalancing weight between cage 2 and counterweight 3. In the example, the drive 5 is arranged in the upper region of the building. It could also be arranged at another location in the building, or in the region of the cage 2 or the counterweight 3.

(18) The elevator cage 2 is equipped with a braking system which is suitable for securing and/or retarding the elevator cage 2 in the case of an unexpected movement or in the case of excess speed. In the example, the braking system is arranged below the cage 2 and it is electrically activated (not illustrated). A mechanical speed limiter, such as is usually used, can accordingly be eliminated.

(19) FIG. 2 shows the elevator installation of FIG. 1 in a schematic plan view. The braking system contains two elevator braking devices 20. The two elevator braking devices 20 are, in this example, coupled by means of a synchronization rod 15 so that the two elevator braking devices 20 are actuated together. An unintended braking at one side can thus be avoided. The two elevator braking devices 20 are possibly realized to be constructionally the same or with mirror symmetry and they act when required on the guide rails arranged on both sides of the cage 2. The guide rails 6 include for that purpose brake surfaces 7 which in co-operation with the elevator braking devices 20 can effect braking of the elevator cage 2. It is also possible to dispense with the synchronization rod 15. However, electrical synchronization means are then recommended, which can help ensure simultaneous triggering of elevator braking devices arranged on both sides of the elevator cage.

(20) FIG. 3 shows a possible embodiment of an elevator braking device 20. The elevator braking device 20 is constructed so as to co-operate with a brake surface 7. This brake surface 7 is a component of the guide rail 6.

(21) The elevator braking device 20 is disposed in a first operational setting B1. In this setting, the elevator braking device 20 does not brake, i.e. the elevator cage 2 can travel. The elevator braking device 20 comprises a brake housing 21, which is arranged in a support 9 to be slidable by way of a slide connection. The slide connection substantially comprises a sliding guide 23, which is arranged in the support 9 and the brake housing 21 is mounted in this sliding guide 23 by way of a guide rod 22. The support 9 is fastened to the elevator cage 2 or it is a component of the elevator cage 2. The elevator cage 2 and thus the support 9 are guided along the guide rail 6 by means of a guide shoe 8 (see FIGS. 1 and 2).

(22) Other forms of slide connections are also possible. Thus, the brake housing 21 could, for example, slide in slide tracks of the support 9 or it could be connected by way of a pivot bearing with the elevator cage 2 or support 9. The brake housing 21 is thus arranged to be displaceable horizontally or perpendicularly to the brake surface 7. A brake element 25 is arranged in the brake housing 21.

(23) The brake element 21 is connected with the brake housing 21 by way of a rotary bearing 28. In the illustrated embodiment the brake element 25 has a first clamping region 26. In the first operational setting (B1) the brake element 25 is disposed in a middle position. This middle position is set by, for example, a centering spring 42. The centering spring 42 engages the brake element 25 and pulls it by a low force into the middle position, as apparent in FIG. 3. The clamping region 26 is so realized with respect to a longitudinal axis 28a of the rotary bearing 28 or describes a curved shape in such a manner that a radial spacing R from the longitudinal axis 28a to the clamping region 26 increases, starting from the center position, over a rotational angle α. A braking region 27.1, 27.2 is connected with the clamping region 26. The braking region 27.1, 27.2, as a tangential continuation of the clamping region 26, snugly adjoins this. In the example, the brake element 25 has a first braking region 27.1 and a second braking region 27.2, which are arranged at the two ends of the clamping region 26. This braking element is provided for braking in both travel directions. The clamping region 26 is possibly provided with a knurling or with transverse grooves so as to enable good gripping of the clamping region 26 with the brake surface 7. The braking region 27.1, 27.2 is realized as a brake lining. It can include a special braking material such as, for example, ceramic, sintered material or hardened brake shoes.

(24) An actuator 32 and a force store 24 are arranged in the support 9. The actuator 32 forms, by way of a blocking roller 33 or a corresponding entrainer, an abutment for the brake housing 21 and thus for the brake element 25. The force store 24—in the example, a compression spring—presses the brake housing 21 and thus the brake element 25 against the actuator 32. The position of the brake element 25 with respect to the guide rail 6 and thus with respect to the brake 7 is thus determined. The position of the actuator 32 and thus the position of the brake element 25 can, if required, be precisely set by suitable setting means. The actuator 32 is fixed by a retaining device, in the example in the form of a clamping electromagnet 36 and associated armature plate 37.

(25) In addition, a brake plate 30 is disposed opposite the brake element 25. The brake plate 30 is arranged in the brake housing 21 and supported in this by way of brake springs 31. The brake plate 30 is so arranged that the guide rail 6 projects into the intermediate space defined by brake plate 30 and brake element 25. A spacing between brake plate 30 and brake element 25 is so selected in the first operational position B1 that a sufficient transit play S1, S1′ is ensured with respect to the guide rails 6 or the corresponding brake surfaces. The brake plate 30 could alternatively also be realized as a fixed counter-lining, without resilient support by means of brake springs, or it could be realized in the form of a brake wedge. It may thereby be possible, for example, to achieve an additional amplification of braking force in dependence on travel direction.

(26) A pressing-on force F24 of the force store 24 is so selected that in the case of actuation the brake element 25 is so strongly pressed against the brake surface 7 that on relative movement between brake surface 7 and brake housing 21 it is securely entrained. In one embodiment a force of at least approximately 85 N (Newtons) is required for that purpose. With consideration of friction losses such as arise, for example, in the case of coupling of two elevator braking devices 20, as illustrated in the example of FIGS. 1 and 2 by means of the synchronization rod 15, an effective retaining force F32 of the actuator 32 is, in the example, approximately 1000 N (Newtons). A sufficient security is thus present for the elevator braking device 20 not to be actuated due to vibrations and at the same time the force store 24 can be sufficiently strongly dimensioned so that in every instance a reliable actuation of the elevator braking device 20 can take place. With consideration of a lever ratio of approximately 1:4 at the actuator 32 a required magnetic retaining force F36 approximately 250 N results. A corresponding clamping electromagnet has a diameter of approximately 25 mm (millimeters) for a constructional height of approximately 20 mm (millimeters). An actuating system of that kind can thus be realized with small dimensions. It requires little space. These value details are informatory. They can be established by the skilled person on the bases of the geometric and constructional realization of the participating components.

(27) For actuation of the elevator braking device 20, in a first step, as apparent in FIG. 4, the clamping electromagnet 36 is switched to be free of current and the armature plate together with the complete actuator 32 is free. The pressing force F24 of the force store 24 is thereby free and presses the brake housing 21 and thus brake element 25 by the corresponding pressing force F21′ against the guide rail 6 or the corresponding brake surface 7 in position B2. The longitudinal axis 28a of the rotary bearing 28 is thus adjusted by the amount of the transit play S1. In the example, the entire brake housing 21 has displaced together with the brake element 25. Accordingly, a transit play S2 on the opposite side of the guide rail correspondingly increases.

(28) In a subsequent relative movement between brake surface 7 and brake housing 21 the pressing force F24 has the effect that the clamping region 26 is entrained by the brake surface 7. The clamping region 26 is for that purpose possibly structured or knurled. Through entraining the clamping region 26 the brake element 25 rotates about the axis 28 of rotation. The longitudinal axis 28a is, in correspondence with the increase in the radial spacing R from the longitudinal axis 28a to the clamping region 26, pushed back in the direction of the original, first operational setting. In FIG. 5 it is apparent how in the course of pushing back the longitudinal axis 28a and thus also the brake housing 21 regain the position corresponding with the first operational setting. Due to the weight matching of the actuator 32 the armature plate 37 again lies at the clamping electromagnet 36. The weight matching results from the arrangement of the lever 35, the armature plate 37 and the influence of a possible assisting spring 39 or a corresponding assisting weight 38.

(29) However, the clamping region 26 further rotates, as apparent in FIG. 6, and ultimately pushes back the brake housing 21 in such a manner that the brake plate 30 similarly lies against the guide rail 7 and it continues to rotate until the braking region 27.1 is reached, as illustrated in FIG. 7. Up to this working point the longitudinal axis 28 and thus equally the braking housing 21 were further reset, whereby ultimately the brake springs 31 of the brake plate 30 are stressed. Through the pressing force, which is built up in that manner, of brake plate 30 and braking region 27.1 against the brake surfaces 7 of the rail 6 braking of the elevator cage 2 finally takes place.

(30) As apparent in FIGS. 6 and 7, after the actuator 32 has reached its reset position, i.e. when the armature plate 37 rests against the clamping electromagnet 36, the brake housing 21 can if required be moved away from the actuator 32 or the blocking roller 33 thereof. It is critical that the actuator 32 in this brake setting of the elevator braking device 20 is again in a reset position B3 corresponding with the first operational setting.

(31) Insofar as the elevator braking device 20 is now to be rest, as a first step a retaining current of the clamping electromagnet 36 can be switched on. The actuator 32 is thereby fixed or held without the clamping electromagnet 36 having to bring about an air gap or other form of resetting energy.

(32) For resetting, it can be merely necessary for the elevator cage 2 to be moved back oppositely to the previous braking direction. The brake element 25 is thereby rotated back and the brake housing 21 is set by the force store 24 and the fixed actuator 32 into the first operational setting B1, as illustrated in FIG. 3. The brake element 25 is itself brought back into its center position by, for example, the centering spring 42.

(33) Another embodiment is illustrated in FIGS. 8 to 14. Basically, in this embodiment a safety brake device is integrated in the elevator braking device, as is known from, for example, the publication DE 2139056. The elevator braking device 20 is integrated in a structure of the elevator cage 2. The elevator cage 2 also includes the guide shoe 8, which is provided for guidance of the elevator cage along guide rails (not illustrated). The elevator braking device 20 includes a brake element 25 with a clamping region in the form of a control eccentric 25.1 and brake shoes 25.2, which are mounted in the brake housing 21 to be rotatable about an axis 28 of rotation. A synchronization rod 15 with synchronization lever 16 connects the two elevator braking devices 20 arranged on either side of the elevator cage 2. It is thereby ensured that the two elevator braking devices 20 come into engagement with one another. It is also possible to selectively provide, at this synchronization rod, centering parts (not illustrated) which set a center position of the control eccentric 25.1, and switches (not illustrated) can be provided, which can establish a rotation of the synchronization rod and thus an operational setting of the elevator braking device 20.

(34) The brake housing 21 is fastened to the elevator cage 2 by way of the support 9, wherein a guide rod 22 enables a lateral or horizontal displacement of the brake housing 21 with respect to the support 9 and the guide rail 6.

(35) In normal operation or in the first operational setting B1, the brake element 25 and the brake plate 30 are arranged at a spacing from the guide rail 6, as illustrated in FIGS. 9 and 10. FIG. 9 shows in this regard a perspective back view and FIG. 10 shows a plan view of the elevator braking device 20 in the first operational setting B1. The actuator 32 is fixed by the clamping electromagnet 36 and the blocking roller 33 of the actuator 32 holds the brake housing 21 by way of a settable abutment 21.1, against the effective force F24 generated by the force store 24, in the first operational setting. As an alternative to the settable abutment 21.1, the position of the brake housing 21 can also be set by way of the blocking roller 33. For that purpose the blocking roller 33 can, for example, be fastened to the blocking lever 35 by an eccentrically formed axle. Through rotation of this axle of the blocking roller 33 the lateral position of the brake housing 21 in the support 29 and thus the position with respect to the brake surface 7 or guide rail 6 can be precisely set.

(36) The clamping electromagnet 36 is switched off for the purpose of actuation of the elevator braking device. Consequently, the blocking roller can no longer provide a blocking force, whereby the force store 35 can urge the brake housing 21 together with the brake element 25 against the brake surface 7 of the guide rail 6, as is illustrated in FIGS. 11 and 12. Due to the adjustment of the brake housing, a play between brake element 25 and brake surface 7 can be eliminated, whereas the play S1+S1′ between brake plate 30 and rail 6 is increased in the first actuating step.

(37) Through a relative movement between brake element 25 and guide rail 6 the control eccentric 25.1 of the brake element 25 is rotated and the brake shoe 25.2 is pressed by way of the control eccentric 25.1 against the brake surface 7 of the guide rail 6 (cf. FIG. 8), whereby braking of the elevator cage 2 takes place. In this regard the brake plate 30 is pulled up by way of the brake housing 21, whereby the guide rail 6 is clamped in place between the brake plate 30 and the brake shoe 25.2 and whereby at the same time the brake housing 21 is pushed back again in the direction of the first operational setting. The assisting weight 38 of the actuator 32 in that case ensures that the actuator 32 follows this resetting until the actuator 32 is disposed back in its original position corresponding with normal operation. This can mean that a holding mechanism of the actuator, for example an electromagnet or a latch, for fixing the actuator in this reset position B3 corresponding with the first operational setting B1 merely has to be switched on, whereby the actuator 32 is reset without a further resetting action. Accordingly, the holding mechanism can be of economic design. The elevator braking device 20 is shown in FIGS. 13 and 14 in the braking setting, wherein the actuator, as described, is disposed back in its position B3 corresponding with normal operation.

(38) The illustrated arrangements can be varied. The brakes can be attached above or below the cage 2. In addition, several brake pairs can be used at a cage 2. The braking device can also be used in an elevator installation with several cages, wherein then each of the cages has at least one braking device of that kind. If needed, the braking device can also be attached to the counterweight 3 or it can be attached to a self-propelling cage.

(39) Having illustrated and described the principles of the disclosed technologies, it will be apparent to those skilled in the art that the disclosed embodiments can be modified in arrangement and detail without departing from such principles. In view of the many possible embodiments to which the principles of the disclosed technologies can be applied, it should be recognized that the illustrated embodiments are only examples of the technologies and should not be taken as limiting the scope of the invention. Rather, the scope of the invention is defined by the following claims and their equivalents. We therefore claim as our invention all that comes within the scope and spirit of these claims.