U.S. patent number 3,783,978 [Application Number 05/274,320] was granted by the patent office on 1974-01-08 for stop control for elevators.
This patent grant is currently assigned to Elevator Safety Company. Invention is credited to Douglas Hamilton.
United States Patent |
3,783,978 |
Hamilton |
January 8, 1974 |
STOP CONTROL FOR ELEVATORS
Abstract
An elevator safety mechanism that includes a means for stopping
movement of elevators in the event of earthquakes or other
shocks.
Inventors: |
Hamilton; Douglas (Baltimore,
MD) |
Assignee: |
Elevator Safety Company
(Baltimore, MD)
|
Family
ID: |
23047707 |
Appl.
No.: |
05/274,320 |
Filed: |
July 24, 1972 |
Current U.S.
Class: |
187/278;
200/61.45R |
Current CPC
Class: |
B66B
7/046 (20130101); B66B 7/028 (20130101); B66B
5/022 (20130101); B66B 7/048 (20130101) |
Current International
Class: |
B66B
7/02 (20060101); B66B 7/04 (20060101); B66B
5/02 (20060101); B66b 005/16 () |
Field of
Search: |
;187/73,91,28,1,35,39,29
;212/39 ;307/10 ;254/174,175 ;200/61.45 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Blunk; Evon C.
Assistant Examiner: Lane; H. S.
Attorney, Agent or Firm: Levy; Sherman
Claims
What is claimed is:
1. A stop control for elevators comprising T-rails, roller guides
having spring-loaded wheels engaging said rail, a support member
connected to said roller guide and having an auxiliary wheel
journaled therein, an auxiliary track insulated from said rail and
engaged by said auxiliary wheel, and an electrical circuit having
said auxiliary wheel and track electrically connected thereto.
2. In an elevator system having a shaft, vertically disposed guide
rails within said shaft, an elevator cab located adjacent to said
guide rails, a plurality of guide rollers mounted on said cab and
engageable with said rails, and means for moving said cab; the
improvement comprising auxiliary track means vertically disposed
within said shaft, a source of electrical energy connected to said
track means, electrical contact means carried by said cab and
normally engaging said track means to complete a normally closed
electrical circuit, and means in said closed circuit for disabling
said means for moving said cab, whereby opening said normally
closed circuit prevents the motion of said cab.
3. The structure as defined in claim 2 in which said auxiliary
track means includes an electro-conductive material mounted on said
guide rails and insulated therefrom.
4. The structure as defined in claim 2 in which said auxiliary
track means is a wire rail independently supported within said
shaft and extending substantially the entire length thereof.
5. The structure as defined in claim 2 in which said electrical
contact means carried by said cab includes wheel means mounted for
rolling movement along said track means.
6. The structure as defined in claim 2 in which said electrical
contact means carried by said cab includes brush means mounted for
sliding movement along said track means.
7. The structure as defined in claim 2 including resilient means
urging said electrical contact means into engagement with said
track means and permitting slight movement of said cab relative to
said guide rails, and stop means for limiting movement of said
electrical contact means.
Description
This invention relates to elevators, and more particularly to a
means for automatically stopping movement of elevators in the event
of earthquakes or other severe jarring.
The primary object of the present invention is to provide a stop
control mechanism for elevators so that in the event of a severe
jarring resulting from an earthquake or other severe disturbance,
an electrical circuit will be interrupted to shut down or close the
elevator system.
A further object is to provide a stop control for elevators that is
actuated during periods of severe shock, and wherein the stop
control of the present invention can be used on various types of
elevators such as traction elevators or hydraulic elevators, and in
one form of the present invention there is provided an auxiliary
wheel that engages a corresponding traction member while in another
form of the invention there is provided a sliding contact or brush
for selectively maintaining the circuit in operative position.
Still another object is to provide such a stop control for
elevators that is economical to manufacture and efficient in
operation and which is rugged in structure and fool-proof in
use.
These and other objects of the present invention will become
apparent from a reading of the following specification and claims,
together with the accompanying drawings, wherein like parts are
indicated by like reference numerals, and wherein:
FIG. 1 is a side elevational view of an elevator illustrating one
application of the present invention.
FIG. 2 is a top plan view thereof.
FIG. 3 is an enlarged elevational view of the device per se.
FIG. 4 is a side elevational view illustrating the device in
operative condition.
FIG. 5 is a view generally similar to FIG. 3, but showing the parts
in a different position causing the circuit to be broken.
FIG. 6 is a top plan view of the structure of FIG. 3.
FIG. 7 is a sectional view taken on the line 7--7 of FIG. 3.
FIG. 8 is an elevational view generally similar to FIG. 3, but
illustrating a modified or alternative form of the present
invention.
FIG. 9 is a horizontal sectional view taken through the device of
FIG. 8.
FIG. 10 is a schematic diagram illustrating the present
invention.
FIG. 11 is a fragmentary side elevational view illustrating a
further modified or alternative form of the present invention.
FIG. 12 is a front elevational view of the device of FIG. 11.
FIG. 13 is a sectional view taken on the line 13--13 of FIG.
11.
FIG. 14 is a top plan view illustrating a counterweight guidance
mechanism.
FIG. 15 is a side elevatioonal view of the apparatus of FIG.
14.
FIG. 16 is a fragmentary enlarged elevational view of the
current-containing member with the counterweight brush elements
slidably engaging the same.
FIG. 17 is an enlarged sectional view taken on the line 17--17 of
FIG. 16.
Referring in detail to the drawings, and more particularly to FIGS.
1 - 7 of the drawings, the numeral 20 indicates a portion of an
elevator system that includes the usual walls 21 and 22 as well as
a cab or cage 23 and a member such as a counterweight 24, FIG. 2.
The usual T-rails 25 may be provided as well as a cable assembly
26. The rails 25 may be supported on sectional members 27 that are
suitably affixed to walls such as the walls 21. There is further
provided roller guides that are indicated generally by the numeral
28, and the roller guides 28 include the usual wheels such as the
wheels 29, 30 and 31. Studs 32, 33 and 34 are provided for these
wheels and for these studs spring members 35, 36 and 37 are mounted
thereon, the numeral 38 indicating the base of the roller guide 28.
The roller guide 28 includes arms such as the arms 39 that are
pivotally mounted, as shown in the drawings.
In accordance with the present invention, there is provided a
suitable control for elevators whereby in the event of a severe
earthquake or other severe shock, the up and down motion of the
elevator cab 23 will be automatically stopped to provide a safety
feature for elevators such as the elevator system 20. In order to
accomplish this, in FIGS. 1 - 7 there is illustrated one form of
the invention wherein there is provided a stop control safety
device indicated generally by the numeral 40 that comprises a
support member 41 that has a slot 42 therein for the projection
therethrough of a pin 43. The support member 41 includes a first
portion 44, FIG. 7, and the portion 44 has an aperture or opening
45 therein through which extends a stud or bolt 46, and a coil
spring 47 is circumposed on the stud 46. The numeral 48 indicates a
body piece that has a lug 49 suitably affixed thereto or formed
integral therewith, and the lug or bracket 49 has an aperture 50
therein for the projection therethrough of a corresponding stud or
bolt.
The support member 41 further includes a portion 51 that is
arranged at right angles with respect to the portion 44, and, as
shown in FIG. 3, an offset portion 52 interconnects the portion 51
to an end portion 53, and the end portion 53 of the support member
41 has a stud 54 journaled therein which provides a support for an
auxiliary wheel 55. The wheel 55 normally engages or contacts an
auxiliary track 56 that is adapted to be insulated from the portion
58 of the wheel 55 by means of insulation 57. The rail 25 includes
a base portion 59 as shown in FIG. 6.
Referring to FIG. 10 of the drawings, there is illustrated
schematically a wiring diagram for the present invention wherein
the numeral 122 indicates a transformer that may be suitably
operatively connected to the control panel for the present elevator
system, and the electrical circuit further includes relays 124 as
well as wires or conductors 123.
Referring now to FIGS. 8 and 9 of the drawings, there is
illustrated a modified or alternative stop control for elevators
that is indicated generally by the numeral 63. In the form of the
invention shown in FIGS. 8 and 9, instead of using a wheel such as
the auxiliary wheel 55, a sliding brush contact assembly is used.
Thus, in FIGS. 8 and 9, the numeral 64 indicates a support member
or arm that is adapted to be connected to the roller guide 28 by
means of a stud or bolt and nut assembly 65, and the circuit member
64 includes a first portion 66 through which the stud 65 extends.
The support member 64 further includes a second portion 67 that has
a support portion 68 affixed thereto or formed integral therewith,
and the numeral 69 indicates a contact or brush on the portion 68,
and the brush 69 is mounted for sliding movement along an auxiliary
track 70 on a channel 71 that may be insulated as at 72 from a
spacer 73 on the portion 59 of the rail 25.
From the foregoing, it will be seen that there has been provided a
stop control for elevators that will automatically stop the
vertical movement of the elevator in the event of a severe shock
such as that which occurs during an earthquake or the like. In use
with the parts arranged as shown in the drawings and more
particularly as shown in FIGS. 1 - 7 and FIG. 10 of the drawings,
the parts are normally in a position as shown in FIG. 4 so that the
auxiliary wheel 55 will move out of contact with the track 56 so
that this will break or interrupt the electrical circuit shown in
FIG. 10. FIG. 10 illustrates diagramatically or schematically the
wiring diagram, and it is to be understood that when the electrical
circuit is broken the usual control mechanism or control panel for
the elevator will be deactivated so that no further movement of the
elevator will be possible. Thus, severe injury, death or the like
to occupants of the elevator will be minimized.
In the modifications of FIGS. 8 and 9 instead of using a rolling
contact wheel 55, a sliding contact assembly 63 is adapted to be
used, and in FIGS. 8 and 9 the brush 70 on the projection 69 is
adapted to normally maintain the electrical circuit closed as the
elevator functions in the usual manner. However, in the event of a
severe shock, the brush 69 will be moved away from the track 70 to
interrupt the circuit and stop any further movement of the elevator
so that injury or death to the personnel in the elevator will be
minimized.
The parts can be made of any suitable material and in different
shapes and sizes as desired or required.
It will be seen that there has been provided a position sensing
device with 360.degree. directional coverage for elevators for
instant stop control during during shock such as earthquake
conditions. The present invention can be used for counterweights,
traction elevators, hydraulic elevators or the like. The assembly
includes a rolling contact wheel as shown in FIGS. 1 - 7 and 10 or
a sliding contact as shown in FIGS. 8 and 9 which rides on an
auxiliary insulated track or suspended wire of low voltage such as
23 volts that runs the length of the shaft in both front and rear
and rail-to-rail position. The electrical guide members are adapted
to be affixed to or near the main guide members such as roller
guides or sliding guides with the controlling contacts being
totally insulated in closed electrical circuit which will actuate a
shut-down control panel mounted on the master control panel of the
elevator, breaking the electrical contact from the sliding shoe of
the rail, activates the instant shut-down control. The system can
only be reactivated by the elevator mechanic after full inspection
and repair of the assembly.
The present invention may use either a complete cut-off switch or
time delay to cause the elevator to go to the closest floor or an
instant stop can be used. It is understood that various accessories
can be used wherever needed, and, for example, 1/4 inch bronze wire
supported with small clips for overheated circuits that may be
adjustable can be provided wherever needed or required. Thus, there
is provided a method of stopping the elevator when extreme
vibrations occur, and the present invention is a switch assembly
that is in a normally closed circuit that causes a control panel to
be activated when a severe disturbance occurs so that a safety
control is provided to stop the elevator. Thus, if there is a
sufficient shock or vibration, the elevator will stop so that the
people can get out of the elevator.
The present invention can be installed on new equipment or new
elevator systems or existing systems can be readily modified to
permit the device to be mounted thereon, and the present invention
has a traveling safety switch in a normally closed circuit. The
present invention will also function to stop further movements of
the elevator in the event of vibrations or shock from bombs or any
other disturbance beside earthquakes. The moving shoe contact 69 is
adapted to engage the stationary auxiliary track 70 in the standard
channel 71 that may be insulated as at 72 from the member 73.
The present invention will not interfere with normal use or
operation of the elevator and can only be actuated when a severe
shock occurs.
The pin 43 in the slot 42 is arranged so that some sliding movement
can occur without breaking the circuit, but, if there is a severe
vibration, the parts will move from the position shown in FIG. 4 to
the position shown in FIG. 5 to cause the contact to move from the
track and break the circuit. The auxiliary track such as the track
56 or the track 70 extends the full length of the elevator
shaft.
FIG. 2 illustrates a counterweight type of elevator, but it is to
be understood that the present invention is not to be limited to
this type of elevator, but may be used with hydraulic
elevators.
In the modification of FIGS. 8 and 9 a sliding type brush contact
is used instead of the auxiliary wheel 55. The parts are
spring-loaded to normally stay on the track or rail. There is
provided a contact switch that rides on an insulated track that is
connected to the main rail, and there is provided the normally
closed circuit, and when the elevator is sufficiently jarred by an
earthquake the electrical circuit will be broken or interrupted to
actuate a master switch or control panel to stop the elevator. A
support member such as the support member 41 can pivot about an
axis such as the axis 74 when vibration occurs. The track 56 or 70
may be affixed to or placed in any suitable manner as by insulated
rivets, adhesives or the like. As shown in the drawings, as long as
the arm 55 engages the track 56, the circuit is closed, but, in the
event of a severe jarring, the wheel 55 will move away from the
track 56 to actuate the stop control which prevents further
movement of the elevators.
Referring now to FIGS. 11 - 13 of the drawings, there is indicated
a stop control mechanism 80 for use with elevators comprising
T-rails 81, and the numeral 82 indicates conventional roller guides
having spring-loaded wheel 83 engaging the rail 81. A micro-switch
84 is suitably connected to each of the roller guides 82, and the
micro-switch 84 may be electrically connected to the circuit by
wires 85. The numeral 86 indicates an arm or lever that is
pivotally supported as at 87, and the arm 86 may include a first
portion 88 as well as a second portion 89, and the portions 88 and
89 are joined or interconnected by an offset portion 90, FIG. 12.
The numeral 91 indicates an auxiliary wheel that is journaled in
the portion 89 by means of a shaft or pin 92, and the auxiliary
wheel 91 is mounted for travel or movement along the portion 93 of
the rail 81. The numeral 94 indicates a spring member that has its
ends anchored as at 95 and 96 to the arm 86 and micro-switch 84,
whereby the spring 94 will normally urge or bias the wheel 91 into
engagement with the portion 93 of the rail or track 81. The numeral
97 indicates a plunger or actuating pin for the micro-switch 84 and
the actuating pin 97 is adapted to be selectively engaged by the
adjacent edge of the portion 88 of the arm 86, as shown in FIG. 11.
As shown in the drawings, there is provided the usual arms 98 for
the wheels 83 of the roller guide 82.
Attention is now directed to FIGS. 14 - 17 of the drawings wherein
there is illustrated a counterweight system that includes
counterweights 99 and rails or tracks 100, and the numeral 101
indicates stop control devices that include conductors 102 that
have a spring member 103 suspending the upper end thereof from an
anchor 104 on an overhead structure 105.
The numeral 106 indicates an insulator that has a rail clamp 100
connected thereto, FIG. 16, and a lever or arm 108 is connected to
each roller guide 109. The numeral 110 indicates a securing element
or screw member that may be spring-loaded as at 111, and a fastener
or nut 112 is arranged in threaded engagement with a threaded
portion of the securing element 110. The contact shoe 113 is
pivotally connected to a bracket 115 as at 116, and the shoe 113
includes a portion 114 for sliding engagement or contact with the
rail 102. The numeral 117 indicates a supporting piece that is
connected to the insulator 106 for engaging the wire rail 102, as
shown in FIG. 16. An opening 118 in the lever 108 provides
clearance for the projection therethrough of the securing element
110 whereby the parts can move slightly, as later described in this
application.
With the device 80 of FIGS. 11 - 13, the parts are arranged or
constructed so that in the event of a certain amount of vibration
or jarring there will be no interruption of the circuit or
associated mechanism since contact will be maintained. However, if
there is sufficient vibration or shock from an earthquake or the
like, the circuit will be broken or interrupted due to the
provision of the micro-switch 84. The micro-switch 84 is operated
by means of the conductors 85, and it is to be understood that one
of the devices 80 is arranged on each side of the elevator, and
these devices 80 are suitably operatively connected together in
series. The wheel 91 is mounted or journaled on the spring-loaded
arm 86, and the arm 86 can pivot about the pivot pin 87, the wheel
91 being journaled on the end of the arm 86 as at 92. The opposite
end of the arm 86 normally engages the point 97 of the micro-switch
84 to maintain a closed circuit. Sliding outward movement of the
wheel 91 will permit the corresponding end portion 88 to move a
slight distance which will not be enough to break the contact or
circuit. However, when the wheel 91 moves out beyond a certain
distance, the end portion 88 of the arm or lever 86 will disengage
from the contact 97 and open the circuit to thereby stop the
elevator to prevent damage or injury to the personnel. The spring
94 serves to bias or urge the arm 86 in the proper direction.
With reference to the device 101 shown in FIGS. 14 - 17, this
construction also allows slight movement of the parts so that there
will be no interruption of the circuit during the normal slight
vibrations that occur when the elevator is being used. However, in
the event of a severe shock or vibration that results from an
earthquake or the like, the spring 111 and associated parts will
provide sufficient give and clearance to permit the arm or lever
108 to move and interrupt the circuit. Thus, for slight vibrations
during normal use of the elevator the opening 118 in the lever 108
will permit slight movement of the parts with uninterrupted
circuit, but in the event of a major disturbance or shock, the arm
108 will move a sufficient distance to engage the fastener 112 so
as to separate the shoe 113 and its contact part 114 from the rail
102 to stop the movement of the elevator. Further, the usual roller
guide wheels 119 can leave the track 100 for small distances, and
there is enough play in the area of the spring 111 in the area 120,
and the brushes 114 are spring-loaded as at 111 so that when the
wheels 119 move out far enough, they will pull the brushes 114 off
of the wire rail 102 to stop further movement of the elevator.
FIGS. 14 - 17 illustrate a typical counterweight application of the
present invention using a sliding dual brush and wire principle,
and it is believed that this is the most practical way to use the
present invention with counterweights. One of the major problems is
with the counterweight leaving the rail due to excessive shock.
When this happens the counterweight is free to swing and acts as a
battering ram. Further, when the car passes the counterweight when
it is off the rails, the counterweight can collide with the car and
even go through the cab, and this has been known to happen. Also,
in the case of the car leaving the rails, with either a hydraulic
type on a piston or a traction type supported with cables,
excessive damage to the car and injury to the occupants may result
or occur. The present invention is intended to cover the concept of
having a limit switch on the guide or follower wheel. Thus, the
follower wheel, when leaving the rail face, may travel a distance
of approximately 5/8 inch to actuate the switch and shut down the
car which already has a cutoff switch in its control system, and
this of course relates to cars only. Also, the car application will
not require the suspended bronze wire such as the wire 102 shown in
FIG. 16. Thus, there is a counterweight problem which the brush and
wire concepts fits ideally, and heretofore there has been no way of
handling this problem. There is also a car problem which must be
treated differently, either by use of a wheel on the guide or
independently of the guide to act as a limit switch cutoff. The
counterweight system works on low voltage (32 volts) because it is
exposed and the car system works on a normal voltage because it can
be electromechanically constructed and not exposed.
In FIGS. 11 - 13 the micro-switch 84 functions as a cutoff switch,
and a pair of these switches are provided to be operatively
connected together. Thus, in FIGS. 11 - 13 a dual mechanical cutoff
switch using existing car voltage and any movement in excess of 5/8
inch will activate the cutoff switch to effect an accelerated
controlled stop or wired to time or zone switch delay cutoff
allowing the car to proceed manually to the nearest floor and stop,
and this can be re-set only by the elevator mechanic. FIGS. 11 - 13
illustrate a typical car monitor guide cutoff switch that can be
wired to existing control or monitoring existing slide guide
shoes.
In FIGS. 14 - 17 the clamps 107 may be suitably connected to the
rails 100, and the support members 117 can be insulated as at 106
from the rail clamps 107, and the members 117 help support a bronze
wire rail 102 that can be stretched from the top of the elevator
shaft to the bottom. The wire rail 102 can be under spring tension
and insulated, and the wire rail may be supported at intervals by
rail clamps and clips as needed or desired. As an alternate
arrangement, bronze bars approximately 3/16 inch .times. 1/1 inch
can be used in place of the round wire 102. In FIG. 17 there is
illustrated a detail of the spring-loaded dual contact bronze shoe
as at 111, and FIGS. 14 - 17 illustrate a typical bronze wire rail
for a counterweight guide monitor.
FIG. 10 illustrates a typical wiring diagram of a stop circuit or
current reduction from 230 volts to 32 volts, wherein there is
provided a transformer 122 with conductors 123, and relays 124 may
be electrically connected in the circuit. As an alternative
arrangement, a time or zone switch delay cutoff can be wired into
the circuit to allow the elevator to proceed to the nearest floor
at very low speed and then stop.
With further reference to the counterweight application shown in
FIGS. 14 - 17, the numeral 99 indicates a counterweight, and the
numeral 107 indicates typical rail clamps, while the contact bronze
wire 102 is mounted vertically on the rail with insulated clips.
There is also provided the dual brush contact for both top guides,
and there can be insulated and connected as shown on the
counterweight monitor guide. The counterweight brush contact can be
a roller guide. A brush contact may be added to the contact shoe in
the roller guide. The correct application monitor wheel is an
independent member and is adapted to have spring pressure to keep
the wheel in contact with the rail face independent of the spring
pressure on the roller guide wheel. This independent pivoting
roller guide wheel operates the cut-off switch. The actual location
of the cut-off switch may be in the position shown or it may be
slightly higher as needed.
It will now be clear that there is provided a device which
accomplishes the objectives heretofore set forth. While the
invention has been disclosed in its preferred form, it is to be
understood that the specific embodiments thereof as described and
illustrated herein is not to be considered in a limited sense as
there may be other forms or modifications of the invention which
should also be construed to come within the scope of the appended
claims.
* * * * *