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
  • B66B5/28—Buffer-stops for cars, cages, or skips
  • B66B5/284—Buffer-stops for cars, cages, or skips mounted on cars or counterweights
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B66—HOISTING; LIFTING; HAULING
  • B66B—ELEVATORS; ESCALATORS OR MOVING WALKWAYS
  • B66B17/00—Hoistway equipment
  • B66B17/12—Counterpoises

Definitions

• This invention generally relates to elevator systems. More particularly, this invention relates to an elevator counterweight having a buffer supported on the counterweight.
• Elevator systems often include an elevator car and counterweight coupled together by a rope so that the two move together within a hoistway, for example. It is common practice to provide a buffer in a pit to absorb impact with the counterweight in the event that the counterweight drops to a lowest possible position where the counterweight contacts the buffer. The position of the buffer typically dictates the range of motion of the counterweight in a downward direction, which corresponds to a range of motion for the elevator car in an upward direction.
• An example counterweight for use in an elevator system includes a frame that defines an outer edge of at least one side of the counterweight.
• a buffer member is supported by the frame and moveable between a first position where a first fixed length of the buffer member extends beyond the outer edge and a second position where a second, shorter fixed length of the buffer member extends beyond the outer edge.
• One example includes a locking member that selectively locks the buffer member in the first and second positions, respectively.
• a controller activates the locking member responsive to an elevator system operation condition for appropriately controlling the position of the buffer member relative to the frame.
• One example includes a receiver portion of the counterweight frame that at least partially receives the buffer member.
• the buffer member is moveable within the receiver portion such that a first length of the buffer member is received in the receiver portion when the buffer member is in the first position. A second, greater length of the buffer member is received in the receiver portion in the second position.
• the buffer member is effectively retractable into the counterweight.
• An example elevator system includes an elevator car supported for vertical movement.
• a counterweight is associated with the elevator car such that the counterweight moves when the elevator car moves.
• a buffer member is supported on the counterweight for movement with the counterweight.
• the buffer member has a first fixed position relative to the counterweight that allows a first range of movement of the elevator car.
• the buffer member has a second fixed position relative to the counterweight that allows a second, greater range of movement of the elevator car.
• One example includes a controller that maintains the buffer member in a selected one of the first or second positions responsive to an elevator system operation condition. In one example, the controller maintains the buffer in the first position when the elevator system is in an inspection mode.
• the counterweight is moveable in a direction toward a structure so that the buffer member contacts the structure to cause the buffer member to move into the second position.
• Figure 1 schematically illustrates selected portions of an elevator system.
• Figure 2 schematically illustrates an example counterweight designed according to an embodiment of this invention including a buffer member in one operating position.
• Figure 3 schematically illustrates the embodiment of Figure 2 with the buffer member in another operating position.
• FIG 1 schematically shows an elevator system 20 that includes an elevator car and a counterweight 24 that are coupled by a load bearing assembly 26.
• the example arrangement includes sheaves 28 over which the load bearing assembly 26 travels to cause movement of the elevator car 22 between different levels in a building as desired in a known manner.
• a controller 30 controls movement of the elevator car 22 and the counterweight 24.
• An example counterweight 24 is schematically shown in Figure 2.
• the counterweight 24 includes a structure 32 that has at least one outer edge 34, which defines a lower edge of the counterweight 24 in the illustration.
• the example structure 32 comprises a frame that supports a plurality of plates 36 in a known manner to establish the desired mass of the counterweight 24.
• a receiver portion 38 is supported by the structure 32. In one example, the receiver portion 38 is generally cylindrical and hollow.
• a buffer member 40 is at least partially received within the receiver portion 38 such that the buffer member 40 is supported by the structure 32 for movement with the counterweight 24.
• the example buffer member 40 includes a fixed length body 42.
• a cushion member 44 is located near one end of the body 42.
• One example cushion member 44 comprises a spring.
• Another example cushion member 44 comprises elastomeric material.
• a stop portion 46 is located near an opposite end of the body 42. The stop portion 46 controls the amount of movement of the buffer member 40 relative to the receiver portion 38. In the position shown in Figure 2, the stop member 46 encounters a stop surface 50 when the buffer member 40 is in a fully retracted position within the receiver portion 38.
• locking members 52 have moveable portions 54 and maintain the buffer member 40 in the illustrated, retracted position.
• the body 42 includes positioning portions 56 and 58 that cooperate with the locking members 52 to maintain the buffer member 40 in a selected position relative to the counterweight 24.
• the moveable portions 54 are received within recesses 56 or 58 depending on the position of the buffer member 40 relative to the counterweight 24.
• the moveable portions 54 have a sufficient strength to withstand any impact between the buffer member 40 and a structure beneath the counterweight 24 during movement of the counterweight 24 and still maintain the buffer member 40 in a desired position.
• the moveable portions are designed to withstand an impact associated with the counterweight 24 moving at a speed up to the tripping speed of a governor that operates in a known manner.
• the retracted position of the buffer member 40 shown in Figure 2 corresponds to a normal elevator system operating position. During normal elevator system operation, a maximum range of motion of the elevator car 22 and the counterweight 24 are desirable. Maintaining the buffer member 40 in a retracted position allows the outer edge 34 of the counterweight 24 to approach a structure at a lower end of a hoistway, such as within a pit.
• the lowermost position in the example of Figure 2 corresponds to the cushion member 44 contacting an appropriately positioned structure near the bottom of a hoistway. The lower that the counterweight 24 is able to travel, the higher that the elevator car 22 is able to travel.
• a controller 60 controls the locking members 52 to selectively release the body 42 to move between the retracted position shown in Figure 2 and the extended position shown in Figure 3.
• a top of car inspection box may be used to signal the controller 30 regarding a desired operation of the locking members 52.
• the locking members 52 comprise electromechanical devices such as solenoids.
• the controller 60 controls operation of those devices to retract the moveable portions 54 so that they are clear of the recesses 56 when it is desirable to allow the buffer member 40 to move into the extended position of Figure 3.
• the weight of the body 42 causes the buffer member 40 to effectively fall into the extended position.
• the stop portion 46 on the body 42 cooperates with a support surface 62 of the receiver portion 38 to limit the amount of movement of the buffer member 40 into the extended position.
• the controller 60 then operates the locking members 52 until the moveable portions 54 are received in the recesses 58. This locks the buffer member 40 into the extended position shown in Figure 2.
• the extended position shown in Figure 3 is useful during inspection procedures, for example, because the fixed length of the body 42 extending beyond the outer edge 34 provides for a more limited range of motion of the counterweight 24.
• the counterweight 24 is not able to travel to as low a position as was possible when the buffer member 40 was in the position shown in Figure 2. Accordingly, the elevator car 22 is not permitted to travel to as high a position when the buffer member 40 is in the extended position shown in Figure 3. This provides for maintaining a desired amount of overhead clearance between the elevator car 22 and an overhead structure such as a machine support.
• the controller 60 operates the locking members 52 to allow the buffer member 40 to move into the extended position of Figure 3 whenever the elevator system is placed into an inspection mode.
• the controller 60 responds by controlling the locking members 52 to allow the buffer member 40 to assume an extended position as schematically shown in Figure 3.
• the controller 60 is a portion of the elevator system controller 30. In another example, the controller 60 is a separate, dedicated controller. In another example, the locking members 52 can be manually controlled for selectively locking the buffer member 40 into a desired position relative to the counterweight 24.
• the counterweight 24 can be allowed to move downward (according to the drawings) until the buffer member 40 contacts a structure that effectively pushes the buffer member 40 upward relative to the downwardly moving counterweight 24.
• the hoistway pit includes a structure that contacts the cushion 44.
• the controller 30 automatically moves the elevator car 22 and counterweight 24 in a manner to facilitate moving the buffer member 40 into the retracted position by lowering the counterweight 24.
• a mechanic or technician manually causes movement of the elevator system components so that the buffer member 40 is effectively pushed into the retracted position as the counterweight 24 approaches a structure near the bottom of the hoistway, for example.
• the disclosed example provides cost saving and space saving advantages compared to arrangements where a buffer is maintained in a hoistway pit. With the disclosed example, there is less need for space and materials in a pit. Additionally, there is a savings in labor costs as no buffer need be installed on site in the pit.

Landscapes

• Maintenance And Inspection Apparatuses For Elevators (AREA)
• Cage And Drive Apparatuses For Elevators (AREA)

Applications Claiming Priority (1)

Publications (3)

Family

ID=36578339

Family Applications (1)

Country Status (4)

Families Citing this family (2)

Family Cites Families (10)

• 2004
  • 2004-12-03 WO PCT/US2004/040297 patent/WO2006062499A2/en not_active Ceased
  • 2004-12-03 EP EP04812742A patent/EP1828043B1/de not_active Expired - Lifetime
  • 2004-12-03 AT AT04812742T patent/ATE556019T1/de active
  • 2004-12-03 ES ES04812742T patent/ES2386722T3/es not_active Expired - Lifetime

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