U.S. patent number 3,575,604 [Application Number 04/858,677] was granted by the patent office on 1971-04-20 for motion control on doors of rapid transit cars.
This patent grant is currently assigned to General Signal Corporation. Invention is credited to Joseph H. Smith.
United States Patent |
3,575,604 |
Smith |
April 20, 1971 |
MOTION CONTROL ON DOORS OF RAPID TRANSIT CARS
Abstract
A vehicle door control system is provided for a rapid transit
car. The door is actuated by a drive means in response to commands
issued by a designating means. The motion of the vehicle is
regulated by a power controller. The improved system includes
vehicle function means for monitoring the various operational
parameters of the vehicle and checking means responsive to the
vehicle function means, the designating means and the power
controller. The check means determines that the door of the car can
be safely opened.
Inventors: |
Smith; Joseph H. (Lynbrook,
NY) |
Assignee: |
General Signal Corporation
(Rochester, NY)
|
Family
ID: |
25328883 |
Appl.
No.: |
04/858,677 |
Filed: |
September 17, 1969 |
Current U.S.
Class: |
307/9.1; 105/341;
180/281; 246/187B |
Current CPC
Class: |
E05F
15/40 (20150115); E05Y 2900/51 (20130101) |
Current International
Class: |
E05F
15/00 (20060101); H02j 001/00 () |
Field of
Search: |
;180/103,105,107,111,112,113 ;307/9,10 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Schaefer; Robert K.
Assistant Examiner: Hohauser; H. J.
Claims
I claim:
1. A vehicle door control system on a rapid transit car, the doors
actuated by a drive means in response to commands provided by open
and close designating means, and the car operatively controlled by
a power controller wherein the improved door control system mounted
on the car comprises:
vehicle function means for monitoring operational parameters of the
car; and
check means governing said drive means for determining that the
doors of the car can safely be opened including:
first check means responsive to the car function means and the
power controller; and
second check means responsive to the car function means and the
designating means, each producing enabling signals for conduction
to the drive means under safe conditions.
2. The control system of claim 1 wherein the car function
monitoring means comprises:
a brake pressure detector means for manifesting when the brakes of
the car are applied to a predetermined pressure threshold; and
a speed detector means for manifesting when the car achieves a
predetermined range of speed.
3. The improved control system of claim 2 wherein the speed
detector comprises:
speed sensor means for producing signals proportional to the
velocity of the car; and
switching means responsive to the speed sensor signals activated
when the car achieves a predetermined range of speed.
4. The vehicle door control system according to claim 2 wherein the
checking means checks the operability of the brake pressure
detector means and the speed detector means by maintaining a stick
circuit energized of a check relay.
5. The vehicle door control system according to claim 4 wherein the
checking means also checks the operability of the power
controller.
6. The vehicle door control system according to claim 1 wherein
means is provided for rendering operation of the doors to open
positions only provided that the designating means is actuated
after the car function means has determined that the car has
substantially come to a stop.
Description
BACKGROUND OF THE INVENTION
This invention relates to power-operated door mechanisms and
particularly to a control system for the operation of doors on
rapid transit vehicles.
Prior art door controls operated by the conductor on a rapid
transit car have a number of problems in terms of safety of
operation. One is the possibility of a door opening while the train
is moving. If the door switch is actuated to an OPEN position at
any time, the doors will open regardless of the fact that the train
may be moving. If the train is speeding through a tunnel between
stations, an actuation of the door control would open the doors
immediately. With a passenger car filled to capacity, as occurs
during rush hours, the result would be catastrophic. In present day
systems, this is somewhat alleviated by automatic drive motor
cutoff and emergency brake actuation or in some systems, by service
brake actuation, when a premature door opening is detected. It
takes, however, a substantial amount of time for a speeding train
to stop and the protection of the passengers is not adequate.
Another situation of potential danger involves the loading and
unloading of passengers. If the brakes of the car are suddenly
released, there is a possibility of the car rolling, while people
are trying to get on or off. One may easily picture a passenger
slipping and possibly being seriously injured under such
circumstances.
In order to avoid the above situations, brake pressure detectors
may be utilized. However, even assuming the cars are equipped with
apparatus for detecting speed and an acceptable brake pressure
level, still another dangerous situation might occur under the
following conditions:
A train leaves one station and is traveling to the next stop. The
speed detector senses that the car is moving and through its
circuitry, the doors are inhibited from opening. The brake pressure
detector senses that the brakes are not engaged, and through
another set of circuits prevents door opening. Even if the door
control were switched to OPEN, two safety devices would prevent
door opening, while the train is moving. However, there is another
factor of which account has not yet been taken. Should the train be
stopped between stations with the door control switched to OPEN,
the doors will open when the required conditions are satisfied,
i.e., the car is stopped and the brakes are applied. Passengers who
might be leaning or pressed against the doors would thus be subject
to obvious hazard.
There is another possiblity for danger. The brakes may be on at the
proper pressure, the door OPEN command initiated at the proper
time, and the train stopped, but the drive motors may still be
receiving power, which means that power cutoff to the motors has
failed to occur and the wheels are straining against the brakes.
Here, there is presented a danger of premature release of the
brakes and in the time it takes for the doors to close, serious
injury could occur.
The present invention overcomes the aforementioned problems and
provides a safe and reliable door control system.
It is therefore a purpose of this invention to provide an improved
safe control system for power-operated rapid transit car doors.
It is another purpose of this invention to include various
monitoring devices for detecting the operational parameters of the
transit car.
It is another purpose of this invention to check the monitored
information against predetermined conditions incorporated into the
system.
It is another purpose of the invention to cause an automatic door
closure upon the occurrence of an unsafe condition.
SUMMARY OF THE INVENTION
A vehicle control system for use in rapid transit cars has been
provided wherein a drive means actuates the doors in response to
commands from a designating means and a power controller is used
for regulating the motion of the car. The improvement includes a
car function means for monitoring various operational parameters of
the car. A checking means is provided which is responsive to the
car function means, the power controller and the designating means
for determining conditions necessary for safe opening of the door.
A driving means operates the doors in accordance with the OPEN and
CLOSE signals.
BRIEF DESCRIPTION OF DRAWINGS
For a better understanding of the present invention together with
other and further objects thereof, reference is had to the
following description taken in connection with the accompanying
drawings.
FIG. 1 is a block diagram showing the control system of the present
invention.
FIG. 2 is a schematic diagram of the preferred embodiment of the
present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Door 10 and driving means 11 are standard devices installed in
rapid transit cars and are the subject matter to be controlled in
accordance with the invention. Car function monitor 13 and checking
means 12 operate in conjunction with switch means 14 to enable and
disable the drive means 11 operating the door 10. Only when all of
the functions in car function means 13 agree with the conditions of
checking means 12 will switch means 14 allow drive means 11 to
operate doors 10.
Car function means 13 includes a speed detector 15 which transmits
a signal to switch means 14 when a car speed of less than a
predetermined value is detected. Brake pressure detector 17
determines when the brakes of the car are engaged and a signal to
switch means 14 is produced when a specified value of pressure is
detected. Door switch position detector 22 transmits a signal to
switch means 14 when the door switch position detector 22 is in a
neutral position.
Included in the apparatus of this invention is a power controller
20 which regulates the motive power of the transit car, and door
switch 22 which designates commands to the drive means 11 for
opening and closing the doors 10 in the left and right sides of the
car.
Checking means 12 includes first check 16 which is responsive to
speed detector 15, brake air-line detector 17, and power controller
20. In addition, second check 21 included in checking means 12, is
responsive to door switch 22, brake pressure detector 17, and speed
detector 15, and inhibits a door opening if the door switch 22 is
at other than the neutral position when the train is moving. In
order for drive means 11 to operate door 10, all of the devices
included in checking means 12 as well as all of the devices in car
function means 13 must be energized, the failure or disagreement of
any of the devices in car function means 13 will cause a signal to
be transmitted to drive means 11 which demands the door-closed
condition.
The operation of the mechanisms by which these devices interact is
shown schematically with reference to FIG. 2. The system is shown
functioning correctly with the doors opened on the left side of the
car.
Door switch 22 operates left-right relay 31 from positive energy
through either contact L or R which indicates respectively whether
a left or right door opening is desired, while contact CL is the
CLOSED or neutral tap. As seen, door switch 22 energizes either
wire LD or RD for opening the doors 10. Any negative current placed
on either wire LD or RD will cause the doors 10 to close, and as is
shown, further in the discussion, the system's safety is keyed to
this fact. When left-right relay 31 is energized, contacts 33 and
35 controlled by this relay partially complete a circuit along
wires LD and RD respectively. Speed detector 15 responsive to speed
sensor 20 in car function means 13 operates relay 37 when a
predetermined speed range is achieved. This relay 37 is energized
only when speed sensor 20 in combination with detector 15 senses a
speed of less than a predetermined value preferably in the order of
3 miles per hour. Contacts 40 and 42 provide a signal path for
opening the doors 10 when relay 37 is energized. Brake pressure
switch 21 operates brake pressure detector 17. Switch 21 is closed
when brake pressure is applied to a minimum allowable pressure in
the order of 35 p.s.i. Relay 16 incorporated in brake pressure
detector 17 controls contacts 44--49, with the contacts 48 and 46
providing a signal path for opening doors 10.
Relay 50 is used as part of the first check 16 to check the
integrity of brake pressure detector 17, speed detector 15, and
power mode information is also used in this first checking
operation. Motor 23 drives the transit car through axle 24.
Controller 20 regulates the power transmitted to motor 23. The
motorman operates the controller 20 using control lever 25. The
legends A/P and C/B associated with wires 51 and 52 respectively
stand for wires that are tapped off power low-voltage leads in the
transit car controller 20 and indicate an all-power or acceleration
mode (A/P), and a coast-and-brake or deceleration mode (C/B)
respectively. Wire A/P energizes relay 50 through contacts 38, 44
and its own front contact 53 and wire C/B energizes relay 50 along
wire 52 also through the front contact 53. The relay 50 is provided
with a slow release feature by the addition of capacitor 54 and
resistor 55 forming a timing circuit for the relay.
As shown, the transit car is stopped. If the doors are closed by
switching contact 30 to the CL position, and power is delivered to
the transit car, the motor 23 should begin to start up and
accelerate the car, the slow release feature is built into relay 50
in order that the train accelerate past the threshold of the speed
detector 15, i.e., 3 miles per hour, within approximately 5 seconds
after startup. Under these conditions, when the all-power signal is
transmitted along wire 51, the coast and braking signal along wire
52 is disconnected, momentarily deenergizing relay 50. If the car
accelerates properly, then within 5 seconds of startup, a threshold
speed of 3 miles per hour should be achieved. When the threshold
speed is detected, relay 37 controlled by speed detector 15 is
deenergized, closing contact 38. Contact 44 is dropped by
deenergization of relay 16 when brake pressure switch 21 is
released. With contacts 38 and 44 closed, relay 50 remains in an
energized condition along wire A/P through front contact 53 even
after wire C/B is deenergized. If, however, either of the contacts
38 or 44 do not close within the 5 second period, then relay 50
drops automatically maintaining the doors 10 closed. The doors 10
will not reopen again until relay 50 is energized by depressing
reset button 60.
The combination using powder mode shift, brake pressure and speed
detection provide for a reliable method of assuming that the train
has stopped before the doors are open. If the motor power is off,
the brakes are activated at a pressure of 35 p.s.i. and a speed of
less than 3 miles per hour is detected, then the train will stop
within a few seconds. This has been discovered by testing for
optimum characteristics of car speed and brake pressure.
Relay 61 is a second part of the check means 12. Under stopped
conditions, relay 61 receives energy from positive energy through
contacts 39, 45 and its own front contact 62 to negative energy.
Under running conditions, relay 61 is energized along an alternate
path directly to the relay coil through switch 32. That is, when a
speed of less than 3 miles per hour is achieved, detector 15
energizes relay 37 closing contact 39. If minimum brake pressure is
applied, brake pressure detector 17 energizes relay 16 closing
contact 45. The relay 61 is initially energized from positive
energy through switch contact 32. Capacitor 67 and resistor 68 form
a slow release circuit which keeps relay 61 energized for the
period of time it takes for contact 32 to open and for contacts 39
and 45 to close for sticking relay 61 through front contact 62.
This relay was incorporated into the invention for assuring as
explained previously, that in the event that switch 30 is shifted
to either the L or R contacts, while the train is moving, relay 61
will drop opening contacts 62, 63 and 65. While the train is
running, contacts 45 and 39 are open because their respective
relays are deenergized. Under these conditions, the stick circuit
formed by contacts 39, 45 and front contact 62 of relay 61 is
opened. If contact 30 is switched to either the L or R position
while the train is running, relay 31 energizes, opening contact 32
which deenergizes relay 61. With relay 61 deenergized, contacts 63
and 65 open while contact 64 and 66 close. Under these conditions
negative energy is delivered along wire 70 through contacts 66 and
64 to driving means 11 maintaining the doors 10 closed. The timing
circuit of relay 61, consisting of resistor 68 and capacitor 67,
allows for a lag in switching time such that the checking circuit
is not too sensitive.
The dropping or deenergization of any of the relays 61, 50, 16, 37,
31 causes their respective front contacts 63, 65; 56, 58; 46, 48;
40, 42; 33, 35; to open and their back contacts 64 66; 57, 59; 47,
49; 41, 43; 34, 36 to close these contacts from the switch means 14
and the closing of any one of these back contacts maintains doors
10 closed because of the negative energy applied on driving means
11 through wire 70. In order for the doors 10 to open, positive
energy must be applied to driving means 11 and this can be achieved
only when all of the above-mentioned front contacts are closed.
A description follows showing the interaction of the various
components of the system with particular emphasis directed to some
of the dangerous situations obviated by the invention.
FIG. 2 shows the specific circuitry involved and as previously
stated, the system is shown with the left door 10 open, the car
stopped, brakes applied, power to the motors 23 cut off the door
switch relay 31 energized. Upon these conditions, the system is
operating in such a way that switch means 14 senses correspondence
between the car function means 13 and the check means 12. When it
is desired that the train get under way, the conductor closes the
doors by operating switch 30 to the CL position deenergizing
left-right relay 31 closing contacts 34 and 36 and opening contacts
33 and 35. Negative energy from wire 70 is then conducted to drive
means 11 for closing the left doors 10, through switches 34, 40,
46, 56 and 63.
When the doors 10 are closed, an indication is sent to the motorman
by any conventional means and he disengages the brakes and
energizes the motors 23 of the car. When the car starts up, the C/P
wire indicating a deceleration mode of operation is deenergized
because the controller 20 is switched to an acceleration mode and
wire A/P is energized. Immediately upon release of the brakes,
relay 16 is deenergized because pressure switch 21 is deactivated
open circuiting contact 69 causing an energizing of relay 16. With
relay 16 energized, one of the alternate energy paths to relay 50
is partially completed. The relay 50 is provided with a slow
release feature by adding resistor 55 and capacitor 54. This
permits the car to accelerate past the speed necessary to
deenergize relay 37 controlled by speed detector 15. With relay 37
deenergized, contact 38 closes completing the circuit to relay 50
and maintaining it.
Relay 50 is used for multiplicity of functions. Unless the brakes
of the car are released properly, and the speed of the car is
detected to the above 3 miles per hour within 5 seconds of startup,
relay 50 becomes deenergized. The doors 10 cannot open unless the
relay 50 is energized. Deenergization of relay 50 opens contacts
56, 58 and 53 and closes contacts 57 and 59, the latter two
delivering negative energy to drive means 11 for maintaining the
doors 10 closed. Power mode detection is provided by wires A/P and
C/B for energizing relay 50. The brake pressure detector 17 and
speed detector 15 operate through contacts 44 and 38 respectively.
Unless either of the wires A/P or C/B is energized, relay 50 is
deenergized, which prevents a door opening. In addition, if the
power mode is switched to A/P, then contacts 44 and 38 must close
for maintaining relay 50. This checks the power mode and also that
the brakes are disengaged upon startup and that the speed detector
15 is detecting a speed of greater than 3 miles per hour within 5
seconds of startup. The relay 50 acts as a check on many aspects of
the devices in the car function means 13 acting together.
Door switch check 21 is provided to prevent a premature door
opening if the door switch 30 is activated before the train stops.
If switch 30 is moved to the L or R position while the train is
moving, the doors won't open, because speed detector 15 and brake
pressure detector 17 have, through their relays 37 and 16, operated
their respective back contacts 41, 43 and 47, 49 closed, so that
the doors are receiving negative energy. In addition, whenever door
switch 30 is at other than the CL position when the train is
moving, relay 61 is deenergized by the opening of contact 32. An
alternate path for energization of relay 61 follows from positive
energy, through contacts 39, 45 and front contact 62 of relay 61.
The train must be traveling below the threshold speed so that
contact 39 is closed, and the brakes must be activated so that
contact 45 is closed. Front contact 62 must also be closed before
the stick circuit can operate to maintain relay 61 energized. If
the door switch 30 is operated prematurely, i.e., before the train
stops, then relay 61 drops out opening contacts 62, 63 and 65 and
closing back contacts 64 and 66, maintaining negative energy on the
drive means 11 through contacts 66 and 64. In addition, contact 62
is open and relay 61 cannot be energized until contact 62 is reset
by operating door switch 30, to the CL position deenergizing relay
31, closing contact 32 so that relay 61 picks up. A conscious act
on the part of the conductor is necessary before the doors can open
under these circumstances.
It can be seen that the car function means 13 incorporates various
detection devices which are responsive to the mode of operation of
the operation parameters of the car. These devices produce signals
indicative of the mode of operation of the car manifested by the
switching of various contacts associated with each device. These
signals are sensed by the checking means 12 which produces check
signals manifested by additional contacts being operated. The
contacts operated by the check means 12 and car function means 13
are contained in the switch means 14, and if they correspond, then
the switch means 14 generates an OPEN signal for transmission to
drive means 11 for operating the doors to an open position. This
OPEN signal is in the form of positive energy. If the signals of
the car function means 13 and the check means 12 are out of
correspondence, the doors 10 remain closed because the agreement
detector has delivered a CLOSE signal to the drive means 11 in the
form of negative energy which will cause the drive means to close
the doors or if already in that condition will hold the doors
closed.
The system shown provides for safe door control wherein the
occurrence of any one of a particular set of circumstances will
cause automatic closing of the doors or maintenance in the closed
position depending on the situation. In addition to what has been
said, if it were required to open the car doors 10 under
circumstances which ordinarily would indicated that the doors
should be closed, then any suitable type of switch network may be
employed to bypass the system.
While there has been shown what is at present considered to be the
preferred embodiment of the invention, it will be obvious to those
skilled in the art that various changes and modifications may be
made therein, without departing from the true spirit and scope of
the invention.
* * * * *