Patent Application
20170334679
The present disclosure is generally related to elevator systems and, more specifically, a braking system for an elevator system.
Elevator systems are widely used in a variety of applications for transporting passengers from one point to another. In rare situations, such as during earthquakes, the elevator car in an elevator system may become disengaged with the rails. Typical contemporary elevator systems often include redundant braking (e.g. machine brake and safeties) for such situations. As such, increased requirements for elevators systems include rail to building interface and elevator car holding/braking systems. These additional requirements increase the overall cost of the system by adding mass to the elevator car, and potentially changing motor requirements.
Therefore, an improved braking system for an elevator system is desired.
In one aspect, an elevator system is provided. The elevator system includes a hoistway comprising a hoistway structure, and an elevator car disposed in the hoistway. The elevator car includes a first braking device configured to engage a first braking surface in a first direction in the event of a guidance occurrence, and a second braking device configured to engage a second braking surface in a second direction in the event of the guidance occurrence. In an embodiment, the first direction is opposite of the second direction.
In an embodiment, the elevator system further includes a guidance structure disposed in the hoistway, and the elevator car further includes at least two guiding devices disposed on the elevator car, and configured to engage the guide structure and thereby direct the course of travel of the elevator car. In an embodiment, the guidance occurrence includes at least one of the guiding devices becomes disengaged with the guidance structure, failure of the guidance structure, and the elevator car rotating beyond a guidance limit.
In an embodiment, the first braking device is operably coupled to at least one side of the elevator car adjacent to the first braking surface, and the second braking device is operably coupled to at least one side of the elevator car adjacent to the second braking surface. In an embodiment, the first braking device includes at least one of a retainer member, and a braking pad disposed on the retainer member. In an embodiment, the first braking device is disposed on at least one of an upper portion and a lower portion of the elevator car. In an embodiment, the second braking device includes at least one of a retainer member, a braking pad disposed on the retainer member, and a braking pad. In an embodiment, the second braking device is disposed on at least one of an upper portion and a lower portion of the elevator car.
In an embodiment, the first braking surface includes at least one of a first side of the guidance structure and the hoistway structure. In an embodiment, the second braking surface includes at least one of the first side of the guidance structure, a second side of the guidance structure, and the hoistway wall, wherein the second side is opposite of the first side,
In an embodiment, the at least two guiding devices are disposed on opposite sides of the elevator car. In another embodiment, the at least two guiding devices are disposed on the same side of the elevator car. In an embodiment, the at least two guiding devices includes a first propulsion device. In an embodiment, the second braking device is operably coupled to the first propulsion device. In an embodiment, the at least two guiding devices includes a second propulsion device disposed in the hoistway, wherein the second propulsion device is configured to engage the first propulsion device to direct movement of the elevator car. In an embodiment, the second braking surface comprises the second propulsion device.
The embodiments and other features, advantages and disclosures contained herein, and the manner of attaining them, will become apparent and the present disclosure will be better understood by reference to the following description of various exemplary embodiments of the present disclosure taken in conjunction with the accompanying drawings, wherein:
For the purposes of promoting an understanding of the principles of the present disclosure, reference will now be made to the embodiments illustrated in the drawings, and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of this disclosure is thereby intended.
Referring now to
As shown in
In the embodiment illustrated in
The elevator system 10 further includes a mover 23 and a stationary stator 24 (i.e. propulsion structures). In one embodiment, at least one mover 23 is mounted on each elevator car 18 disposed in each hoistway 12. In one embodiment, the mover 23 may include a plurality of magnets (not shown, e.g., permanent magnets, electromagnets). The stationary stator 24 may be mounted on a support column or on a sidewall of the hoistway 12. In the exemplary elevator system 10, a stationary stator 24 is mounted generally vertically in each hoistway portion 14, 16. The stationary stator 24 may include a plurality of coils of wire (not shown) operably connected to a source of electricity (not shown).
In some embodiments, the elevator system 10 may further include a transfer stator (not shown). Similar to the stationary stator 24, the transfer stator may also include a plurality of coils of wire (not shown) operably connected to the source of electricity (not shown). The transfer stator may be moveable from a first position in the first hoistway portion 14 to a second position in the second hoistway portion 16.
In operation, the interaction of the mover 23 and the stator 24 generates a thrust that propels the elevator car 18 (attached to the mover 23). For example, in one embodiment, the mover 23 (and the elevator car 18 attached to the mover 23) is propelled vertically when the coils of wire of the stator 24 adjacent to the mover 23 are energized. In an embodiment, the mover 23 and the stator 24 are disposed on opposite sides of the elevator car 18. In other embodiments, the mover 23 and the stator 24 are disposed on the same side of the elevator car 18.
In an embodiment, a retainer member 28 is operably coupled to at least one side of the elevator car 18. The retainer member 28 is configured to travel with the elevator car 18 within either the first and second hoistway portions 14, 16. It will be appreciated that the retainer member 28 may be attached to a portion of the guidance structure, a portion of the propulsion structure, or to the elevator car frame to name a few non-limiting examples.
Each retainer member 28 includes a braking pad 30 disposed thereon. In some embodiments, the braking pad 30 may be composed of friction based materials, such as soft rubbers or polymers to name a couple of non-limiting examples. In some embodiments, the braking pad 30 may be composed of metallic braking compounds. In some embodiments, as shown in
In some embodiments, a spring device (not shown) may be attached between the retainer member 28 and the braking pad 30. The spring device is configured to act as a dampener; thus, providing less force on the braking pad 30 in actuation. For example, if the elevator car 18 is empty (i.e., carrying less mass) the spring device may be slightly compressed to provide a braking force less than the maximum available force, such as in situations where the elevator car 18 is full. In such situations, the spring device may be completely compressed to provide the maximum available force against the braking pad 30 to stop the elevator car 18.
In the embodiment shown in
Retainer members 28C, 28D are disposed on the other side of the elevator car 18, with each including a braking pad 30C, 30D, respectively. Retainer member 28C may be positioned on an upper portion of the elevator car 18, and retainer member 28D may be positioned on a lower portion of the elevator car 18. It will be appreciated that the retainer member 28C may be positioned on a lower portion of the elevator car 18, and retainer member 28BD may be positioned on an upper portion of the elevator car 18. Braking pad 30C may be positioned on one side of the guidance structure 32 (e.g. a side of the guide rail near the hoistway structure 13) and braking pad 30D may be positioned on the opposite side of the guidance structure 32 (e.g. a side of the guide rail near the elevator car 18).
In rare instances (e.g., earthquakes), the elevator car 18 may experience a guidance occurrence. In an embodiment, a guidance occurrence includes at least one of the guiding devices becomes disengaged with the guidance structure, failure of the guidance structure, and the elevator car 18 rotating beyond a guidance limit. In one of these occurrences, as shown in
In other embodiments, braking pad 30A and braking pad 30B may be positioned on the same side of the guidance structure 32 (e.g. a side near the hoistway structure 13 or a side near the elevator car 18). In such a configuration the braking pads 30A or 30B may engage the guidance structure 32, the hoistway structure 13 (e.g. wall), or both. Braking pad 30C and braking pad 30D may also be positioned on the same side of the guidance structure 32 (e.g. a side near the hoistway structure 13 or a side near the elevator car 18). In such a configuration the braking pads 30C or 30D may engage the guidance structure 32, the hoistway structure 13 (e.g. wall), or both.
It will therefore be appreciated that the present elevator system 10 includes an retainer member 28, including a braking pad 30 disposed thereon, that is able to act as a safety braking device in the event the elevator car 18 experiences a guidance occurrence.
While the disclosure has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only certain embodiments have been shown and described and that all changes and modifications that come within the spirit of the disclosure are desired to be protected.
