Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B66—HOISTING; LIFTING; HAULING
  • B66B—ELEVATORS; ESCALATORS OR MOVING WALKWAYS
  • B66B5/00—Applications of checking, fault-correcting, or safety devices in elevators
  • B66B5/02—Applications of checking, fault-correcting, or safety devices in elevators responsive to abnormal operating conditions
  • B66B5/04—Applications of checking, fault-correcting, or safety devices in elevators responsive to abnormal operating conditions for detecting excessive speed
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B66—HOISTING; LIFTING; HAULING
  • B66B—ELEVATORS; ESCALATORS OR MOVING WALKWAYS
  • B66B1/00—Control systems of elevators in general
  • B66B1/34—Details, e.g. call counting devices, data transmission from car to control system, devices giving information to the control system
  • B66B1/46—Adaptations of switches or switchgear
  • B66B1/48—Adaptations of mechanically-operated limit switches
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B66—HOISTING; LIFTING; HAULING
  • B66B—ELEVATORS; ESCALATORS OR MOVING WALKWAYS
  • B66B5/00—Applications of checking, fault-correcting, or safety devices in elevators
  • B66B5/0043—Devices enhancing safety during maintenance
  • B66B5/005—Safety of maintenance personnel
  • B66B5/0056—Safety of maintenance personnel by preventing crushing
  • B66B5/0068—Safety of maintenance personnel by preventing crushing by activating the safety brakes when the elevator car exceeds a certain upper or lower position in the elevator shaft
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B66—HOISTING; LIFTING; HAULING
  • B66B—ELEVATORS; ESCALATORS OR MOVING WALKWAYS
  • B66B5/00—Applications of checking, fault-correcting, or safety devices in elevators
  • B66B5/02—Applications of checking, fault-correcting, or safety devices in elevators responsive to abnormal operating conditions
  • B66B5/16—Braking or catch devices operating between cars, cages, or skips and fixed guide elements or surfaces in hoistway or well
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B66—HOISTING; LIFTING; HAULING
  • B66B—ELEVATORS; ESCALATORS OR MOVING WALKWAYS
  • B66B5/00—Applications of checking, fault-correcting, or safety devices in elevators
  • B66B5/02—Applications of checking, fault-correcting, or safety devices in elevators responsive to abnormal operating conditions
  • B66B5/16—Braking or catch devices operating between cars, cages, or skips and fixed guide elements or surfaces in hoistway or well
  • B66B5/18—Braking or catch devices operating between cars, cages, or skips and fixed guide elements or surfaces in hoistway or well and applying frictional retarding forces

Definitions

• This invention relates to a device for the safety stop of an elevator car, particularly in elevators without machine room, and an elevator equipped therewith.
• Elevators with no machine room and a reduced space at the top, and possibly at the bottom, of the shaft are known to require additional measures to maintain a safety space above the car, particularly for maintenance technicians working on the cabin roof.
• mechanical car arresting devices comprising a device with a rod that is manually extended towards a stop at a defined height, limiting a safety space for the maintenance technician on the cabin roof.
• this type of device produces high and harmful abutment stresses on the elevator structure.
• This invention aims at correcting these disadvantages and proposes a device for the safety stop of an elevator car, particularly in elevators without machine room and with a small free space at the top and/or bottom of the shaft in normal operation, characterized in that it includes at least one box mounted relative to the shaft and level with the speed limiting cable of the car overspeed safety device and provided with an articulated fork element that has an end adapted to engage at least one attachment element tied to said speed limiting cable of the car overspeed safety device in the service position of the device to arrest the cable and thus cause a safety stop of the elevator car, and to be disengaged from said attachment element in the inactive position, wherein said fork element in the service position and the cable attachment element are located at an appropriate height in combination with each other in the elevator shaft for the engagement of the attachment element with the fork element to cause the arrest of the elevator car at an adequate height in the shaft to leave at least a safety space for the operator on the cabin roof or in the shaft bottom.
• Said attachment element is advantageously shaped as an olive, but any rigid element forming a protrusion that can engage the end of the fork element may be appropriate.
• Said box may be mounted so as to slide vertically relative to the shaft on a small height, being returned by a spring at a reference height in the shaft; however, the fork element is advantageously mounted so as to slide vertically in the box, e.g. on two vertical posts, to be returned by a spring at a reference height, in order to compensate for the differences in the stopping distance of the car and thus of the speed limiting cable attached thereto.
• This sliding height of the box or of the supporting element of the fork element is slightly greater than the longest safety stopping distance of the car.
• the safety space for the operator on the cabin roof takes this longer stopping distance of the car into account.
• the height of the safety space in the shaft corresponds to the height of engagement of the attachment element on the cable with the fork element plus the longest car stopping distance.
• the service position of the device is obtained as soon as the operator accesses the cabin roof, either by directly actuating an activation switch to inspect the elevator or automatically as soon as a landing door opens, using a safety service switch embedded in the lock thereof or activated when the door opens.
• Said fork element is a longitudinal plate that can be e.g. rectangular and is hinged with a motor drive in the plane of the box, having a slit end, preferably flared outwards, to receive said speed limiting cable with a small clearance and engage with said attachment element.
• Said box comprises a vertical passage for the speed limiting cable formed by an appropriate cutout in its construction walls.
• Said fork element is brought into the service position by an electromagnet with an adequate power supply to move the fork element towards the limiting cable and receive it at its end shaped as a fork or a flared slot and disengage it in the inactive position of the device.
• Said fork element is advantageously hinged with a back mass opposite the fork end relative to its articulation axis, so that in operation, it comes into a natural engagement position with the speed limiting cable in a horizontal position, abutting on the actuating element of the non-powered electromagnet, and is disengaged from the limiting cable in an inclined position when inactive, under the thrust of the actuating element of the electromagnet, which is powered by a switch located slightly downstream of the safety area, e.g. a limit switch for inspection, wherein said electromagnet is actuated in normal operation as the car comes into the safety area of the shaft.
• the electromagnet does not have to be powered except during this upper safety course, the electromagnet can be operated and any blocking avoided, and the device naturally returns into the safety position in case of power failure.
• the device may include other attachment elements, e.g. a second attachment element located slightly lower than the first one, with a greater safety distance from the cabin roof to the shaft ceiling, according to the provided standards, wherein the device has a double upper safety in this case.
• the device may be fitted with at least one attachment element in a lower safety area of the shaft, at the bottom, to prevent an operator being crushed by the elevator car overspeed in the shaft bottom.
• the invention also relates to an elevator equipped with a car safety stopping device as defined above.
• Figure 1 is a schematic elevation view of an elevator equipped with a device according to the invention
• Figure 2 shows the box of the device according to the invention in the inactive position
• Figure 3 shows the box in the service position
• Figure 4 shows the box when the elevator car is stopped, with its springs compressed.
• the device involves the speed limiting cable 5 of the car overspeed safety device 7, which operates both during ascension and descent of the car.
• each of the boxes 9, 9' is provided with a fork element 15, 15' hinged inside the box and in its plane.
• This fork element 15, 15' is shaped as a rectangular plate and has a fork-shaped end 17 with an outward flaring slot turned towards the inside of the box.
• This fork end is adapted to receive the speed limiting cable 5 with a clearance when the fork element is brought into the horizontal service position ( Figure 3) and to disengage therefrom when the fork element is driven into its tilted inactive position ( Figure 2) by a bottom electromagnet 19 mounted in the box.
• the speed limiting cable 5 is provided with two olive-shaped attachment elements
• each of the fork elements 15, 15' of the boxes is provided with a mass opposite the fork-shaped end 17, which naturally brings it into a horizontal position, abutting on an upper abutment element 27 with its fork-shaped end 17 and resting with its opposite end on the pusher element 29 of the bottom electromagnet 19.
• Said electromagnet 19 when powered, pushes the fork element 15 into its tilted position with its pusher element 29 and drives it away from the speed limiting cable 5.
• the fork element 15 and the electromagnet 19 are mounted on a support 31 that is mobile vertically, sliding along two lateral vertical posts 33 attached to the box. This support 31 is maintained in its low position with an elastic return by two identical helical springs 35 inserted over the upper part of a post 33, between the upper wall of the box and an appropriate fold of the support.
• the sliding travel of the support 31 in the box is designed up to a maximum value of 50cm, which corresponds to the longest stopping distance of the speed limiting cable 5 by the safety device 7 and therefore of the elevator car 3 to which it is attached by a connecting lever 34.
• the car travels at low speed (approximately 0.3m per second)
• the car is stopped over a distance of about 2-3cm, with a short displacement of the support 31 in the box by the same distance, and thus a low compression of the return springs 35 ( Figure 4).
• the speed limiting cable presents two said olives spaced apart from each other, one upper olive 23 controlling the stopping of the car with a minimum safety space of at least one meter in height between the car roof 37 and the shaft ceiling 4, and a lower olive 21 controlling the stopping of the car with a larger safety space, where the operator can stand upright on the cabin roof 37 and there is therefore a free height of about two meters between the car roof 37 and the shaft ceiling 4.
• the upper safety stop control box 9 is arranged at a defined height in the shaft relative to said olives 21, 23 on the speed limiting cable 5, so that the stop control of the fork element 15 by each of the olives provides said safety spaces taking account of its sliding displacement in the box.
• the lower box 9' operates in relation with the lower olive 21 as it is at an appropriate height in the shaft to provide a safety space for the operator at shaft bottom 6, with a height of e.g. 0.50m between the car bottom 39 and the shaft bottom 6.
• Each of the upper 9 and lower 9' boxes operates in relation with an inspection limit switch, respectively an upper switch 41 mounted on the cabin roof and a lower switch 43 mounted on the cabin bottom 39.
• the upper switch 41 comprises a mobile lever 45 with a lateral wheel attached to the cabin roof 37 and resting with a spring on a vertical longitudinal cam 47 attached to the elevator shaft.
• the lever 45 resting on the cam 47 corresponds to the closed circuit position in which the electromagnet is powered in normal operation and tilts the fork element 15 to disengage it from the speed limiting cable 5.
• the switch is not in contact with the cam 47, the circuit is open and the fork element 15 can then return to the horizontal service position of the device.
• the lower switch 43 comprises a lower wheel lever 49 that cooperates with a lower vertical longitudinal cam 51 on the shaft to close the electromagnet circuit when resting on the cam and open it when not in contact.
• the function of the boxes is also controlled by a main inspection switch actuated by the operator before inspection (not represented) and by a series of landing door opening safety switches in the elevator (not represented) that activate the safety device as soon as any landing door of the elevator is opened.
• the switches can be mounted in series in the box control circuit.
• the operation of the device shall now be described and easily understood on the basis of the description below.
• the maintenance operator pushes the main inspection switch.
• the safety device 1 is then activated, which deactivates the electromagnet 19 on each of the upper 9 and lower 9' boxes over the entire length of travel of the car 3, and the fork element 15 engages the speed limiting cable 5.
• the car travels at low speed (approximately 0.3m/s).
• the limit switch 41 or 43 opens the elevator control circuit and the car stops.
• the safety device 1 is triggered only if this procedure is executed with an anomaly; if the car continues to move, e.g.
• the fork element 15 of the upper box catches the lower olive 21 of the safety device cable to trigger that device and arrest the car at the first safety barrier of the device, thus providing a space about 2m high between the cabin roof 37 and the shaft ceiling 4. If the lower olive 21 is accidentally missed, the upper olive 23 is caught by the fork element 15 and ensures the second safety barrier to provide the minimum safety space for the operator.
• the device 1 After the maintenance operation has been performed, and as soon as the main inspection switch is deactivated and all elevator landing doors are closed, the device 1 returns to normal elevator operation as described above, with the electromagnet 19 that drives the fork element 15 being powered only when the elevator car enters the upper and lower parts of the shaft.
• the fork element in the device may also directly engage the lever of the overspeed safety device to arrest the elevator car.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Automation & Control Theory (AREA)
• Computer Networks & Wireless Communication (AREA)
• Maintenance And Inspection Apparatuses For Elevators (AREA)

Applications Claiming Priority (1)

Publications (1)

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Family Applications (1)

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• 2004
  • 2004-09-29 EP EP04769540A patent/EP1799602A1/en not_active Ceased
  • 2004-09-29 JP JP2007534102A patent/JP4664370B2/ja not_active Expired - Fee Related
  • 2004-09-29 WO PCT/IB2004/003216 patent/WO2006035264A1/en active Application Filing
  • 2004-09-29 CN CNA2004800440896A patent/CN101027239A/zh active Pending

Non-Patent Citations (1)

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