US3872949A - Overspeed prevention system for elevator cars - Google Patents

Overspeed prevention system for elevator cars Download PDF

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Publication number
US3872949A
US3872949A US046236A US4623670A US3872949A US 3872949 A US3872949 A US 3872949A US 046236 A US046236 A US 046236A US 4623670 A US4623670 A US 4623670A US 3872949 A US3872949 A US 3872949A
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Prior art keywords
generator
voltage
brake
car
detonator
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Expired - Lifetime
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US046236A
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English (en)
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James H Snyder
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Doosan Bobcat North America Inc
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Clark Equipment Co
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Priority to US046236A priority Critical patent/US3872949A/en
Priority to CA112,661A priority patent/CA949001A/en
Priority to GB1873571*[A priority patent/GB1305497A/en
Priority to DE19712129334 priority patent/DE2129334A1/de
Priority to FR7121561A priority patent/FR2096314A5/fr
Application granted granted Critical
Publication of US3872949A publication Critical patent/US3872949A/en
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    • 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
    • B66B5/20—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 by means of rotatable eccentrically-mounted members
    • 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
    • B66B5/06—Applications of checking, fault-correcting, or safety devices in elevators responsive to abnormal operating conditions for detecting excessive speed electrical

Definitions

  • Speed responsive means in the form of an electrical generator is provided on the elevator car and produces an output voltage of one polarity exceeding a predetermined magnitude in response to overspeed in the upward direction and produces an output voltage of the opposite polarity and exceeding a predetermined magni tude in response to overspeed in the downward direction.
  • a first polarity responsive switching means is ef fective to de-energize the elevator motor in a regulated manner in response to upward overspeed.
  • a second polarity responsive switching means responds to the downward overspeed voltage and initiates the application of brake means to stop the elevator car.
  • brake means includes a pair 'of brakes which utilize an actuator including one or more pair of brakes which utilize an actuator including one or more pyrotechnic charges which are provided with electrical detonators
  • the switching means are effective to connect the generator to the detonator circuit for the pyrotechnic charges and, to ensure firing thereof, pulsing means are interposed to provide repetitive firing impulses across the detonator circuit.
  • This invention relates to elevators and, more particularly, to an overspeed prevention system especially adapted for material handling or cargo elevators.
  • a material handling vehicle is movable in an aisle between an array of storage bins to preselected stations for deposit or withdrawal of material units.
  • a vehicle commonly referred to as a stacker vehicle
  • Such a vehicle commonly referred to as a stacker vehicle
  • Such systems are designed to operate at high speed and it is desired to minimize the travel time between stations for the stacker vehicle and minimize the travel time between bins for the elevator.
  • the elevator car is driven upwardly or downwardly, depending upon the destination, simultaneously with the stacker vehicle travel between stations.
  • an overspeed prevention system for an elevator car for both upward and downward travel of the car which is operable independently of the lift cable and mechanical connection with the drive train of the elevator car.
  • the system requires no external source of energization and it may be carried entirely on the elevator car.
  • This is accomplished by means of an electrical generator operatively connected between the elevator car and frame for developing a voltage having a magnitude corresponding to the speed of the car and having a polarity corresponding to the direction of travel.
  • a first unidirectionally conductive voltage responsive switching means is connected with the generator and is adapted to connect it to the electrical initiator for brake means on the elevator car in response to an excessive downward speed.
  • a second unidirectionally conductive voltage responsive switching means is connected with the generator and is adapted to effect a regulated deenergization of the driving motor for the elevator car in response to excessive speed in the upward direction of the elevator car.
  • the overspeed brake control system is independent of spring ac tuators and the application of the brakes is electrically controlled.
  • brake means with a pyrotechnic actuator having an electrical initiator or detonator.
  • the connection of the generator by the switching means to the detonator provides instantaneous application of the brake means.
  • Such an arrangement may be extremely compact and yet have a powerfulbrake actuator. Reliability of operation is assured by provision of plural pyrotechnic charges in-each brake actuator.
  • Each pyrotechnic charge is provided with its own electrical detonator and impulse means is electrically connected between the switching means and the detonators to deliver successive electrical pulses at a high rate to insure the firing of each detonator.
  • an elevator brake for use in an overspeed control system which may be mounted on the elevator car for coaction with reaction means on the elevator frame and having an entirely self-contained actuator, i.e.,
  • the actuator without the need for any mechanical linkage for the initiation of brake application by the actuator.
  • This is accomplished by use of an actuator which is energized by a pyrotechnic charge having an electrical detonator and thus requiring only an electrical connection for initiating the brake application.
  • the brake application is produced by a direct and rigid drive means interconnecting the brake shoes with the actuator piston driven by the pyrotechnic charge.
  • This direct mechanical drive assures positive brake engagement through a wedge or cam displacement mechanism which serves to apply the explosive power of the pyrotechnic charge in a controlled manner to urge the brake shoes into engagement with the reaction member. In this manner the entire brake is self-contained in exceedingly small volume and may be disposed on the elevator car within the channel-shaped guide track with serves as the brake reaction member.
  • FIG. 1 is a perspective view of an elevator including the overspeed brake control system of this invention
  • FIG. 2 is a view in elevation of the brake in the disengaged condition
  • FIG. 3 is an elevation view showing the brake shoes in engaged condition
  • FIG. 4 is a sectional view of the brake taken on lines 4-4 of FIG. 2 and showing the pyrotechnic actuator of the brake;
  • FIG. 5 is a schematic diagram showing the overspeed prevention system for both upward and downward travel of the elevator car.
  • an illustrative embodiment of the invention in an overspeed prevention system for an elevator of the type which is especially adapted for use in a stacker vehicle in an automatic warehouse system.
  • the elevator is adapted for high speed operation under automatic control in a substantially unattended manner.
  • the overspeed prevention system is adapted to respond automatically in an instantaneous and positive manner to an overspeed condition in either the upward or downward direction of the elevator car.
  • an elevator including a car movable vertically within an elevator frame including guide tracks 12 and 14 of channel configuration at opposite sides of the car.
  • Lift means for the car includes a drive chain 16 which is drivably connected through a drive train to an electric motor, not shown in FIG. 1.
  • the overspeed prevention system of this invention includes an electrical speed sensing means in the form of an electrical generator 18 mounted by its stator on the car 10.
  • the rotor of the generator is provided with a pinion gear 20 on its shaft and meshing with a rack gear 22 on the flange of the guide track 12.
  • the generator 18 is preferably a direct current generator with a permanent magnet field and produces an output voltage magnitude corresponding to the speed of rotation with a polarity corresponding tothe direction of rotation.
  • the generator may advantageously employ a permanent magnet rotor and a stator winding having a rectifier connected therewith, thus avoiding the use of a commutator or brushes and slip rings.
  • the elevator is provided with brake means adaptedupon actuation to bring the car 10 to a stop relative to the frame of the elevator.
  • the brake means includes a brake 24 on one side of the car and a brake 26 on the other side of the car.
  • the brakes 24 and 26 are identical to each other and are mounted at opposite ends of a support beam 28 which extends beneath the floor of the car 10 and is adapted to support the same during emergency braking.
  • the brake 24 is disposed within the channel configuration of the guide track 12 with suitable clearance from the guide track and similarly the brake 26 is disposed within the channel of guide track 14.
  • Thebrake 24 comprises a body 30 suitably in the form of a rectangular block which is mounted on the end of the support beam 28 and secured thereto by bolts not shown.
  • a pair of rotatable dogs or brake shoes 32 and 34 are mounted for rotation on the body 30 by a pair of headed studs 36 and 38, respectively, which are suitably press fitted or otherwise fixedly secured in the body 30.
  • the brake shoes 32 and 34 are disposed sideby-side with the pivot axis thereof spaced equidistantly from the centerline of the body 30.
  • the brake shoe 32 is of a generally cylindrical configuration having a flat outer surface 40' and formed with a generally radial protrusion or keeper arm 42 extending transversely of the body 30. It is noted that the keeper arm is of lesser thickness than the body of the shoe 32 and has a front surface recessed therefrom which defines a shoulder 44.
  • the brake shoe 32 is provided with a serrated radial surface 46 extending between the flat surface 40 and the keeper arm 42 to provide a non-skid or biting engagement with the guide track 12 which constitutes the brake reaction member when the brakes are engaged.
  • a flat camming surface or shoulder 48 on the rearward face thereof and extending obliquely of the centerline of the brake body 30.
  • Brake shoe 34 is of a construction similar to that of brake shoe 32 and also comprises a generally cylindri' cal body with a flat outer surface 50 and a keeper arm 52.
  • the brake shoes 32 and 34 are adapted for rolling contact with each other at the circular portions of their peripheral edges.
  • the keeper arm 52 is of lesser thickness than the body portion of the brake shoe 34 and has a front surface flush with that of the body portion but has a back surface which is recessed relative to that of the body portion, thereby providing a shoulder 54.
  • the keeper arm 52 is adapted to overlie the keeper arm 42 with the side thereof in abutment with the shoulder 44 and the side of the keeper arm 42 in abutment with the shoulder 54.
  • the brake shoe 34 is provided with a serrated radial surface 56 which extends between the flat surface 50 and the keeper arm 52 to provide for non-skid or biting engagement withthe other side of the guide track 12 when the brake is engaged.
  • the brake shoe 34 is also provided with a flat camming surface 58 which extends obliquely of the centerline of the brake body 30.
  • the brake 24 is provided with an actuator which comprises a slide bar 62, a piston 64 secured thereto and pyrotechnic charges 66 and 68 disposed in a support block 70.
  • the slide bar 62 is mounted on the brake body 30 for reciprocable motion thereon within an axially extending rectangular groove 72 formed in the body 30 and extending throughout the length of the body.
  • the slide bar is of reduced thickness at its lower end and is formed at an intermediate portion with a cam 74 having one side aligned with the camming surface 48 of the brake shoe 32 and having its other side aligned with the camming surface 58 of the brake shoe 34.
  • the slide bar 62 is also provided with a stop pin 76 adjacent its lower end in engagement with the lower edges of the keeper arms 42 and 52 of the brake shoes 32 and 34, respectively.
  • the piston 64 is of cylindrical cup-shape configuration and is fixedly secured, as by welding of the skirt thereof, to the back side of the slide block 62.
  • the piston 64 is slidably disposed within a cylindrical bore 78 in the body 30 which has a continuous circumferential wall except for an opening into the bottom of the rectangular groove.72. This interconnection of the groove 72 and the bore 78 permits the slide bar 62 and the piston 64 to be connected together and to move reciprocably in the brake body 30.
  • the piston 64 and hence the slide block 62 are resiliently biased in the upward position, as illustrated in FIG. 4, by a helical spring 80 disposed in the lower portion of the bore 78.
  • the support block 70 is a generally cylindrical body with a mounting flange 82 bolted to the body and provided with a slot or groove 84 to accommodate the slide bar 62.
  • the support block 70 includes a cylindrical body portion extending into the piston skirt and includes a pair of axially extending chambers 86 and 88 adapted to receive the pyrotechnic charges 66 and 68, respectively.
  • the pyrotechnic charges are of conventional design and each includes a closed cylinder containing pyrotechnic material and an electrical detonator, the cylinder being formed with a bellows portion to permit axial extension of the cylinder when the pyrotechnic material is exploded.
  • the brake 24 is provided with a switch 90 of conventional type including a plunger actuator which engages the back side of the slide bar 62 when the bar and the piston 64 are in the uppermost position.
  • the switch 90 is provided with contacts which are closed with the plunger in the retracted position, as shown in FIG. 4, and which are opened when the plunger is in the extended position resulting from downward motion of the slide bar 62.
  • the brake 24, as shown in FIGS. 2 and 4, is in the disengaged position and thus it is movable vertically within the guide track 12 with ample clearance between the brake shoes 32 and 34 and the channel flanges of the guide track 12.
  • the brake shoes 32 and 34 are retained in this position by the engagement of the keeper arms 42 and 52 with the stop pin 76 which in turn is supported by the slide bar 62.
  • Slide bar 62 is retained in its uppermost position by the bias spring 80 which engages the piston 64 and urges it along with the slide bar 62 to the uppermost position.
  • the stop pin 76 is moved downwardly away from the keeper arms 42 and 52 and the cam 74 engages the camming surfaces 48 and 58 on the brake shoes 32 and 34, respectively, causing them to rotate clockwise and counterclockwise, respectively. As shown in FIG. 3, such rotation causes the serrated surfaces 46 and 56 to move laterally outwardly into engagement with the channel flanges of the guide track 12. Thus, the serrated surfaces 46 and 56 will bite into the metal of the guide track 12 and in a self-energizing manner the downward thrust of the elevator car 10 will tend to cause additional rotation of the brake shoes 32 and 34 thereby increasing the engagement force thereof with the guide track.
  • the brake 26, which is identical in construction to brake 24, will operate in the same manner simultaneously and bring the elevator car 10 to a stop over a very short distance of travel.
  • the overspeed prevention system of this invention is provided with a control circuit which will be described with reference to FIG. 5.
  • the control system comprises, in general, the generator 18 and a first switching means 92 responsive to overspeed of the car in the upward direction to de-energize the driving motor 94 for the elevator car; it also includes a second switching means 96 responsive to overspeed of the car in the downward direction to energize a detonator circuit 98 for the pyrotechnic charges through a pulsing circuit 100.
  • the generator 18 develops an output voltage with the polarity indicated in FIG. 5 when the car is moving downwardly and-with the opposite polarity when it is moving upwardly.
  • the permanent magnet generator 18 has its output terminals connected across the first switching means 92 which includes, in series connection, a rectifier or unidirectionally conductive device 1.02, a current limiting resistor 104 and the energizing coil of a voltage sensitive relay 106.
  • the rectifier device 102 is poled to conduct when the generator voltage has a polarity corresponding to upward motion.
  • The: relay 106 includes a switching means or contacts 108 adapted to open the energizing circuit of the drive motor 94 when the relay 106 is actuated or pulled in.
  • the energizing circuit for the drive motor 94 also includes the contacts of the switch which, as described above, are opened when the brake 24 is applied.
  • the switching means 96 is also connected across the output terminals ofthe generator 18 and includes a rectifier or unidirectionally conductive device 110 which is poled to conduct in the forward direction when the generator 18 produces a voltage in response to the downward motion of the elevator car 10.
  • the rectifier device 110 is serially connected with a current limiting resistor 112 and the energizing coil of a voltage sensitive relay 114.
  • the relay 114 includes a pair of normally open switch contacts 116 which are closed when the relay 114 is actuated or pulled in.
  • the switch contacts 116 are adapted to connect the generator 18 across the detonator circuit 98 in response to overspeed of the elevator in the downward direction.
  • a capacitor 118 is connected across the contacts 116 for protection thereof against the inductive surge current occurring in operation of the circuit.
  • a transformer 120 is provided with its primary winding connected across the generator 18' through the rectifier device 110 and the switch contacts 116.
  • the secondary winding of the transformer 120 has one terminal connected to the adjacent terminal of the primary winding in autotransformer fashion.
  • the detonator circuit 98 is connected across the secondary winding and includes detonators 122 and 124 of the pyrotechnic charges 66 and 68 in brake 24 and also includes parallel connected detonators 126 and 128 of the pyrotechnic charges in the brake 26.
  • a pair of load resistors 130 and 132 are also connected in parallel across the secondary winding of the transformer 120.
  • the transformer provides a suitable transformation ratio to deliver the required current to the detonators.
  • the transformer 120' and the switching means 96 function as a pulsing circuit for energization of the detonator circuit 98 in a manner to be described.
  • the control system of FIG. 5 responds to overspeed in either direction of the elevator car. Assuming that the car is moving upwardly within the rated speed, the generator 18 will be driven thereby and will produce a voltage across the switching means 92 causing conduction in the forward direction through the rectifier device 102. However, the voltage will be below the threshold value for the relay 106 and the resultant current is insufficient to cause actuation thereof. Under these conditions, the voltage of generator 18 is applied across the switching means 96 and the rectifier device 110 therein in the nonconductive: direction and, accordingly, current flow through the relay 114 is blocked. If the speed of the elevator car 10 in the upward direction should increase beyond the rated speed the voltage developed by the generator 18 will be increased correspondingly.
  • the generator 18 When the elevator car 10 is travelling in the downward direction the generator 18 is driven thereby and develops an output voltage across the switching means 92 and the switching means 96.
  • the polarity of the generator voltage across the switching means 92 is in the non-conductive direction. However, the polarity of the generator voltage'across the rectifier device 110 in switching means 96 is in the forward direction.
  • the voltage across the relay 114 When the downward speed of the elevator car is within the rated speed, the voltage across the relay 114 is below the threshold value and the current flow therethrough is insufficient to pull in the relay. However, when the speed of the car exceeds the rated value, the relay 114 is pulled in and the contacts 116 are closed.
  • the output voltage of the generator 18 is applied across the primary winding of the transformer 120 through the rectifier device 110 and the contacts 116.
  • This causes a transient primary current in the transformer 120 which induces a voltage across the secondary winding and the detonator circuit 98.
  • the detonators 122, 124, 126 and 128 are energized by the resultant current flow and the respective pyrotechnic charges in the brakes 24 and 26 are exploded thereby.
  • the brakes 24 and 26 are applied in the manner previously described and the elevator car 10 is brought to a stop.
  • the transient current therein is initially limited by the reactive impedance and will increase toward a final value which is limited by the resistance of the circuit.
  • This transient current causes a voltage to be induced across the secondary winding and a current impulse in the detonator circuit 98 to energize the detonators.
  • the rate of change of magnetizing flux in the transformer decreases, the current increases toward its final value thus decreasing the voltage drop across the inductive reactance of the transformer primary winding.
  • the voltage drop is correspondingly increased across the resistance of the circuit, including the internal resistance of the generator.
  • the transformer 120 is desirably adapted to be driven into magnetic saturation by the magnetizing current thus causing an abrupt decrease in the flux rate of change and the current im- 8 pulse rise time.
  • the resulting large surge current loads down the generator and the terminal voltage decreases so that the voltage across the relay 114 drops below the threshold value and the contacts 116 are opened.
  • Interruption of the current in the primary winding causes the magnetic flux field to collapse and induce a voltage of reverse polarity across the secondary winding.
  • a second current impulse is delivered to the detonator circuit 98 to fire any detonators which were not fired by the first impulse.
  • a limit cycle occurs in the operation of the switching means 96 and the transformer 120.
  • the generator voltage will increase again if the overspeed condition persists until the voltage across relay 114 exceeds the threshold value and the cycle described above is repeated. Consequently, the pulsing circuit operates to apply repeated firing impulses to the detonator circuit to ensure that the detonators are fired to bring the elevator car to a stop.
  • the switch is actuated and the contacts thereof are open to interrupt the energizing circuit of the drive motor 94.
  • An overspeed brake control system for an elevator comprising: an electrical generator adapted to be oper-' atively connected with an elevator car to generate a voltage corresponding to the speed of the car, brake means for said car including a pyrotechnic actuator therefor with an electrical detonator, and voltage responsive switching means connected with the generator and adapted to connect said generator with said electrical detonator when the voltage of the generator reaches a predetermined value upon the occurrence of transformer having a primary winding connectable across said generator through said switching contacts and a secondary winding connected across said electrical detonator, the transformer primary being con-,
  • the invention as defined in claim 1 including a pulse producing means connected between said generator and said detonator whereby repeated pulses are applied to the detonator while the speed of the car is excessive.
  • the pulse producing means includes said switching means and reactive impedance adapted to impose a time varying load on said generator so that the voltage thereof varies above and below said predetermined value when the speed is excessive.
  • said pyrotechnic actuator includes plural pyrotechnic charges each having an electrical detonator, all of said detonators being connected in parallel to said pulse producing means whereby the detonators are subjected to repeated voltage pulses to insure that each pyrotechnic charge is fired in response to an overspeed condition.
  • said brake means is provided with electrical switching means operatively connected with said actuator and electrically connected with the drive means for said elevator car and being adaptd to interrupt said drive means when said brake means is actuated by the pyrotechnic actuator.
  • said brake means comprises a brake shoe and operating member connected with said actuator and engageable with said brake shoe for displacing the same to cause energization of said brake means to stop said elevator car.
  • An overspeed prevention system for an elevator comprising: an elevator car movable relative to a frame by a drive motor and comprising a direct current electrical generator operatively connected between the car and the frame and adapted to generate a voltage corresponding to the speed of the elevator car, brake means for said car including an electrically energized actuator therefor.
  • a first unidirectionally conductive voltage responsive switching means connected with the generator and responsive to a predetermined voltage of one polarity for connecting said generator across said electrical energizing means to cause said brake means to be actuated when said elevator car is moving downwardly at an excess speed
  • second unidirectionally conductive voltage responsive switching means connected with said generator and responsive to a predetermined voltage of the other polarity for de-energizing said drive motor when said elevator car is moving upwardly at an excessive speed.
  • said actuator includes a pyrotechnic charge with an electrical detonator.
  • An overspeed brake control system for an elevator comprising: an elevator car movable relative to a frame, brake means for said car including a pyrotechnic actuator therefor with an electrical detonator, a source of voltage on said car, control means responsive to the speed of said elevator car for connecting the voltage source to the electrical detonator, said brake means comprising at least one brake shoe, and an operating member connected with the actuator and engage able with the brake shoe for displacing it into engagement with the brake reaction member.
  • said voltage source is a direct current generator operatively connected between the elevator car and the frame.
  • control means is a voltage responsive switching means connected with the generator and adapted to connect the generator to the electrical detonator when the voltage of the generator reaches a predetermined value.
  • the invention as defined in claim 15 including a pulse producing means connected between the generator and the detonator. 7
  • said brake means includes first and second brakes, each including an actuator with plural pyrotechnic charges, each of said charges having an electrical detonator, said detonators being connected in parallel to said pulse producing means whereby the detonators are subjected to repeated voltage pulses to insure that each pyrotechnic charge is fired in response to an overspeed

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Maintenance And Inspection Apparatuses For Elevators (AREA)
  • Braking Arrangements (AREA)
US046236A 1970-06-15 1970-06-15 Overspeed prevention system for elevator cars Expired - Lifetime US3872949A (en)

Priority Applications (5)

Application Number Priority Date Filing Date Title
US046236A US3872949A (en) 1970-06-15 1970-06-15 Overspeed prevention system for elevator cars
CA112,661A CA949001A (en) 1970-06-15 1971-05-11 Overspeed prevention system for elevator cars
GB1873571*[A GB1305497A (enrdf_load_stackoverflow) 1970-06-15 1971-06-03
DE19712129334 DE2129334A1 (de) 1970-06-15 1971-06-12 Einrichtung zur Verhinderung überhöhter Geschwindigkeiten bei Aufzügen
FR7121561A FR2096314A5 (enrdf_load_stackoverflow) 1970-06-15 1971-06-14

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US046236A US3872949A (en) 1970-06-15 1970-06-15 Overspeed prevention system for elevator cars

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US3872949A true US3872949A (en) 1975-03-25

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US046236A Expired - Lifetime US3872949A (en) 1970-06-15 1970-06-15 Overspeed prevention system for elevator cars

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US (1) US3872949A (enrdf_load_stackoverflow)
CA (1) CA949001A (enrdf_load_stackoverflow)
DE (1) DE2129334A1 (enrdf_load_stackoverflow)
FR (1) FR2096314A5 (enrdf_load_stackoverflow)
GB (1) GB1305497A (enrdf_load_stackoverflow)

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3942607A (en) * 1974-09-06 1976-03-09 Dane Sobat Elevator safety brake
US4121689A (en) * 1977-04-12 1978-10-24 Francois Bonvin Escape mechanism
US4351423A (en) * 1979-11-14 1982-09-28 Valeo Method for limited, gradual disengagement of a brake, and such a brake
US4372427A (en) * 1979-09-21 1983-02-08 Valeo Industrial emergency brake
US5349854A (en) * 1992-05-01 1994-09-27 Otis Elevator Company Elevator speed and position indicating device
US5797472A (en) * 1996-01-26 1998-08-25 Otis Elevator Company Reactive governor
US6354406B1 (en) * 1999-06-30 2002-03-12 Siemens Aktiengesellschaft Safety arrangement for a cable-supported component of a medical device
US20100054900A1 (en) * 2008-08-29 2010-03-04 Houtveen Beheer Achterveld B.V. Lifting apparatus for use in a vehicle
CN108217378A (zh) * 2018-02-11 2018-06-29 广州特种机电设备检测研究院 具有止坠安全装置的电梯
US20190249446A1 (en) * 2018-02-15 2019-08-15 Marshalltown Company Lifting device including telescoping mast
US10662029B2 (en) * 2014-08-29 2020-05-26 Kone Corporation Overspeed governor configured to trigger at different speed levels for an elevator
RU2789908C2 (ru) * 2020-10-23 2023-02-14 Дмитрий Валерьевич Хачатуров Способ управления лифтового электропривода
CN116040173A (zh) * 2022-11-17 2023-05-02 江苏冠猴智能控制设备有限公司 一种食品生产用自动化仓储系统

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102674175B (zh) * 2012-05-18 2014-02-05 上海工程技术大学 以重力自锁的自适应式起吊器
CN116216582B (zh) * 2023-05-09 2023-07-04 山东达驰电气有限公司 变压器装配用吊装装置

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US324751A (en) * 1885-08-18 Safety device for elevators
US767930A (en) * 1904-06-06 1904-08-16 Axel Magnuson Safety appliance and speed-controlling apparatus for elevators.
US2489984A (en) * 1945-02-20 1949-11-29 United Aircraft Corp Explosive-release mechanism
US2511697A (en) * 1947-12-12 1950-06-13 William C Clift Elevator safety apparatus

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US324751A (en) * 1885-08-18 Safety device for elevators
US767930A (en) * 1904-06-06 1904-08-16 Axel Magnuson Safety appliance and speed-controlling apparatus for elevators.
US2489984A (en) * 1945-02-20 1949-11-29 United Aircraft Corp Explosive-release mechanism
US2511697A (en) * 1947-12-12 1950-06-13 William C Clift Elevator safety apparatus

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3942607A (en) * 1974-09-06 1976-03-09 Dane Sobat Elevator safety brake
US4121689A (en) * 1977-04-12 1978-10-24 Francois Bonvin Escape mechanism
US4372427A (en) * 1979-09-21 1983-02-08 Valeo Industrial emergency brake
US4351423A (en) * 1979-11-14 1982-09-28 Valeo Method for limited, gradual disengagement of a brake, and such a brake
US5349854A (en) * 1992-05-01 1994-09-27 Otis Elevator Company Elevator speed and position indicating device
US5797472A (en) * 1996-01-26 1998-08-25 Otis Elevator Company Reactive governor
US6354406B1 (en) * 1999-06-30 2002-03-12 Siemens Aktiengesellschaft Safety arrangement for a cable-supported component of a medical device
US20100054900A1 (en) * 2008-08-29 2010-03-04 Houtveen Beheer Achterveld B.V. Lifting apparatus for use in a vehicle
US10662029B2 (en) * 2014-08-29 2020-05-26 Kone Corporation Overspeed governor configured to trigger at different speed levels for an elevator
CN108217378A (zh) * 2018-02-11 2018-06-29 广州特种机电设备检测研究院 具有止坠安全装置的电梯
CN108217378B (zh) * 2018-02-11 2024-01-02 广州特种机电设备检测研究院 具有止坠安全装置的电梯
US20190249446A1 (en) * 2018-02-15 2019-08-15 Marshalltown Company Lifting device including telescoping mast
RU2789908C2 (ru) * 2020-10-23 2023-02-14 Дмитрий Валерьевич Хачатуров Способ управления лифтового электропривода
CN116040173A (zh) * 2022-11-17 2023-05-02 江苏冠猴智能控制设备有限公司 一种食品生产用自动化仓储系统
CN116040173B (zh) * 2022-11-17 2023-11-21 江苏冠猴智能控制设备有限公司 一种食品生产用自动化仓储系统

Also Published As

Publication number Publication date
CA949001A (en) 1974-06-11
DE2129334A1 (de) 1971-12-23
FR2096314A5 (enrdf_load_stackoverflow) 1972-02-11
GB1305497A (enrdf_load_stackoverflow) 1973-01-31

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