Information
-
Patent Grant
-
6263804
-
Patent Number
6,263,804
-
Date Filed
Thursday, July 22, 199925 years ago
-
Date Issued
Tuesday, July 24, 200123 years ago
-
Inventors
-
Original Assignees
-
Examiners
- Morano; S. Joseph
- Jules; Frantz F.
Agents
- Swabey Ogilvy Renault
- Mitchell; Robert
-
CPC
-
US Classifications
Field of Search
US
- 105 3291
- 105 331
- 105 332
- 105 333
- 105 339
- 105 427
- 105 430
- 105 438
- 105 437
- 105 431
- 105 443
- 105 450
- 105 343
- 104 27
- 104 28
- 104 30
- 280 166
- 296 155
-
International Classifications
-
Abstract
A door system for a railway car which provides for both high and low level access. The door system comprises a sliding door, a platform displaceable between raised and lowered positions for respectively clearing and covering the stairwell of the railway car, and a threshold extending laterally outwardly of the sliding door to provide a continuation of the platform when displaced to its lowered position. The threshold is releasably connected to the sliding door for co-linear movement with the sliding door when the platform is raised, while remaining stationary in a functional position when the platform is lowered for enabling high level boarding.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to door systems for railway vehicles and, more particularly, to door systems which provide for boarding from both high and low level platforms.
2. Description of the Prior Art
Railway vehicles are often used on railroad lines having passenger stations equipped with high boarding platforms extending at the vehicle floor level and others with low level boarding platforms extending at or near ground level.
Accordingly, efforts have been made to develop door systems providing for both high and low level access. For instance, U.S. Pat. No. 5,070,794 issued on Dec. 10, 1991 to Kunst et al. discloses a multi-sectioned sliding door assembly for use with a railway vehicle having a stairwell extending downwardly from the floor of the vehicle to a lower boarding level. The sliding door assembly comprises an upper sliding door displaceable to an open position for high level boarding and a lower sliding door disposed immediately below the upper sliding door and displaceable therewith to an open position for low level boarding. The upper sliding door is supported at the top by a sliding connection to a door overhead structure. An upper threshold is secured to an upper outer section of the lower sliding door to be positioned adjacent an elevated platform of a train station. The lower sliding door is connected via a slide assembly to the railway vehicle structure in the region of the upper threshold platform. In addition, the bottom of the lower door panel is guided in a lower threshold. A stairwell platform is hingedly connected to one side of an upper horizontal plane of the stairwell for covering the same during high level boarding.
Although the door assembly of the above mentioned patent is effective for enabling both high and low level boarding operations, it has been found that there is a need for a simpler system which requires fewer adjustments.
SUMMARY OF THE INVENTION
It is therefore an aim of the present invention to provide an improved door system providing for both high and low level access.
It is also an aim of the present invention to provide a door system which is relatively simple and economical to manufacture.
Therefore, in accordance with the present invention there is provided a door system for a railway vehicle having a door opening and a stairwell extending downwardly from a vehicle floor level to a bottom end of the door opening, the door system comprising a sliding door displaceable between open and closed positions for selectively closing the door opening, a stairwell platform displaceable between a retracted position for clearing the stairwell and an extended position for covering the stairwell, and a threshold extending laterally outwardly of the sliding door substantially at the vehicle floor level, the threshold being releasably connected to the sliding door for conjoint movement therewith when the stairwell platform is in the retracted position thereof, while remaining stationary in a functional position when the stairwell platform is in the extended position thereof for allowing high level boarding.
In accordance with a further general aspect of the present invention, there is provided a door system comprising a sliding door displaceable between open and closed positions, a stairwell platform displaceable between a retracted position for clearing a railway vehicle stairwell and an extended position for covering the stairwell, and a threshold extending laterally outwardly of the sliding door substantially at the vehicle floor level, the threshold being adapted to move with the sliding door and to be made stationary in a functional position thereof by engagement of the threshold with a retainer upon positioning of the stairwell platform to the extended position thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
Having thus generally described the nature of the invention, reference will now be made to the accompanying drawings, showing by way of illustration a preferred embodiment thereof, and in which:
FIG. 1
is a fragmented perspective view of a dual level access door system used in combination with a railway vehicle in accordance with a preferred embodiment of the present invention;
FIG. 2
is a fragmented perspective view of the dual level access door system of
FIG. 1
, showing a sliding door displaced to an open position thereof together with an upper threshold for allowing low level embarkment and disembarkment of passengers;
FIG. 3
is a fragmented perspective view of the dual level access door system of
FIG. 1
, showing the sliding door displaced to the open position thereof independently of the upper threshold which has remained stationary in order to bridge the space between a stairwell platform and an elevated platform of a train station;
FIG. 4
is a longitudinal cross-sectional view of the sliding door, illustrating the construction of a lock mechanism used to selectively connect and disconnect the upper threshold to the sliding door;
FIG. 5
is an enlarged side view of the lock mechanism shown in an engaged position wherein the upper threshold is secured to the sliding door and;
FIG. 6
is an enlarged side view of the lock mechanism illustrating how the lock mechanism is displaced to a disengaged position wherein the upper threshold is disconnected from the sliding door.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Now referring to the drawings, and in particular to
FIGS. 1
to
3
, a dual level access door system
10
suited for use in combination with a railway vehicle
12
and embodying the elements of the present invention will be described.
As seen in
FIGS. 1
to
3
, the railway vehicle
12
has a stairwell
14
extending downwardly from a floor
16
and leading to a door opening
18
defined in a side wall
20
of the railway vehicle
12
.
A stairwell platform
22
is pivotally mounted at a lower edge thereof to a side wall
24
of the stairwell
14
by means of a hinge
26
. A latch
28
is provided for maintaining the stairwell platform
22
in a retracted or raised position thereof adjacent the side wall
24
during low level platform embarkment and disembarkment of passengers. By unlocking the latch
28
, the stairwell platform
22
can be manually swung down to an extended position, as shown in
FIG. 3
, wherein the stairwell platform
22
covers the stairwell
14
and provides a continuation of the floor
16
for allowing ingress and egress of passengers from an elevated boarding platform
30
of a train station. A lock
32
is provided on the floor
16
on the other side of the stairwell
14
for releasably securing the stairwell platform
22
in the extended or lowered position thereof.
The door system
10
further comprises a sliding door
34
formed of an upper section
35
fixedly secured to a lower section
37
by means of a connecting plate
39
bolted or otherwise secured to respective inner surfaces of the upper and lower sections
35
and
37
. The upper section
35
of the sliding door
34
is slidably mounted at an upper end thereof to a door overhead structure (not shown) forming part of the railway vehicle
12
. A strip (not shown) depends from the bottom side of the lower section
37
of the sliding door
34
for engagement in a corresponding longitudinal guiding groove (not shown) defined in the top surface of a lower threshold (not shown) secured to the railway vehicle
12
. The strip is made of a low friction material, such as nylon. An actuating mechanism (not shown) is provided for sliding the door
34
between open and closed positions. The sliding door
34
is slid open into a door receiving cavity
40
provided in the side wall
20
of the railway vehicle
12
.
An upper threshold
42
extends laterally outwardly of the sliding door
34
to provide a continuation of the stairwell platform
22
in order to bridge the space between an elevated boarding platform, such as at
30
, and the stairwell platform
22
. The upper threshold
42
is releasably connected to the sliding door
34
via a lock mechanism
44
.
When the stairwell platform
22
is held in the raised position thereof, the upper threshold
42
is secured to the sliding door
34
, via the lock mechanism
44
, for movement as a unit with the sliding door
34
, as seen in FIG.
2
. This enables passengers to ingress and egress at ground level via the stairwell
14
.
However, when the stairwell platform
22
is in its lowered position, as shown in
FIG. 3
, the upper threshold
42
is disconnected from the sliding door
34
and held in place by the stairwell platform
22
. The sliding door
34
can then be displaced into the door receiving cavity
40
, while the upper threshold
42
remains in a functional position thereof to bridge the space between the stairwell platform
22
and an elevated boarding platform, such as at
30
.
Referring now more specifically to
FIGS. 4
to
6
, there will be described the construction and operation of the upper threshold
42
and of the associated lock mechanism
44
.
As seen in
FIG. 4
, the upper threshold
42
is slidably mounted on a support member
46
inserted in position within the lower portion
37
of the sliding door
34
for movement therewith. The upper threshold
42
is provided with a pair of spaced-apart parallel rail engaging members
48
a
and
48
b
adapted to receive therebetween an horizontal rail
50
formed at an upper end of the support member
46
. The rail
50
extends along an outer side of the sliding door
34
in a direction of motion thereof. An insert
52
made of a low friction material and having an inverted U-shaped portion is fixedly mounted on the rail
50
to provide an adequate sliding surface for the upper threshold
42
. According to a construction of the present invention, the upper threshold
42
and the support member
46
are made of aluminum, whereas the insert
52
is made of plastic.
The outer longitudinal side
54
of the upper threshold
42
extends downwardly to form a guide
56
with the rail engaging member
48
b
. A roller assembly
58
is mounted in the door receiving cavity
40
for engagement within the guide
56
so as to provide a support surface for the upper threshold
42
and at the same time prevent the sliding door
34
from swinging. As seen in
FIGS. 1
to
3
, a support
60
is mounted to the structure of the railway vehicle
12
on the side of the door opening
18
opposed to the door receiving cavity
40
to support the upper threshold
42
when the same is displaced to the functional position thereof. Accordingly, the upper threshold
42
is supported at opposed ends thereof when displaced to its functional position.
As seen in
FIGS. 4
to
6
, the lock mechanism
44
comprises a pivotal latch
64
having first and second end portions
66
and
68
. A pivot pin
70
is provided intermediate the first and second end portions
66
and
68
of the latch
64
to pivotally connect the same to an outer surface
72
of the rail engaging member
48
a
for rotation in a plane parallel to the sliding door
34
. The latch
64
has an inverted V-shaped top surface formed of a first segment
74
and second segment
76
. A spring blade
78
is secured at one end thereof to the first segment
74
and engaged at opposed end thereof with an undersurface
80
of the upper threshold
42
for normally urging an engaging portion or pin
82
extending at right angles from the first end
66
of the latch
64
in the upper end of a vertical slot
84
defined at one end of the connecting plate
39
. In this position, the first segment
74
is substantially parallel to the undersurface
80
of the upper threshold
42
and the latter is connected to sliding door
34
for movement therewith. Accordingly, when the door actuator (not shown) is powered to displace the sliding door
34
to its open position, as seen in
FIG. 2
, the force applied to the sliding door
34
by the door actuator will be transmitted to the upper threshold
42
via the connecting plate
39
. No relative motion will occur between the upper threshold
42
and the rail
50
and, thus, the sliding door
34
and the upper threshold
42
will move as a unit to allow ground level boarding.
It is understood that other catch mechanisms could be used as an alternative to the above described vertical slot
84
.
As seen in
FIGS. 1
,
2
and
6
, the stairwell platform
22
is provided with a pin engaging surface
86
. When the stairwell platform
22
is lowered to its extended position as depicted by arrow
87
in
FIG. 6
, the pin
82
is engaged by the engaging surface
86
, thereby causing the latch
64
to pivot about the pivot pin
70
in a clockwise direction against the spring force exerted by the spring blade
78
so as to displace the pin
82
in a downward direction, as depicted by arrow
88
. This causes by pin
82
to move out of the vertical slot
84
, thereby disconnecting the latch
64
and, thus, the upper threshold
42
from the connecting plate
39
. The stairwell platform
22
is further provided with a pin abutment surface
90
extending at right angles to the pin engaging surface
86
to prevent the upper threshold
42
from being retracted with the sliding door
34
. Therefore, the stairwell platform
22
acts as a retainer having an abutment surface adapted to maintain the upper threshold
42
stationary while the door
34
is being opened. Accordingly, when the sliding door
34
is displaced to its open position, the upper threshold
42
will remain stationary and the rail
50
will slide between the rail engaging members
48
a
and
48
b.
A guard (not shown) may be provided to preclude unauthorized access to the pin
82
. Another guard (not shown) could be mounted to the outer surface of the sliding door
34
to protect the upper threshold
42
from the elements while the sliding door
34
is closed.
The above described door system
10
advantageously simplifies the sliding assembly of the door and reduces the number of adjustments which are required to maintain the functionality of the door system. Furthermore, by slidingly connecting the sliding door
34
to an overhead structure of the railway vehicle
12
and connecting the bottom of the sliding door
34
to a lower threshold
38
via a strip, such as a weather-strip, binding of the sliding door
34
will be prevented upon racking and twisting of the railway vehicle
12
. Finally, the fact that the sliding door
34
always moves as a single unit, allows the same to be more firmly supported by the railway vehicle structure.
Claims
- 1. A door system for a railway vehicle having a door opening and a stairwell extending downwardly from a vehicle floor level to a bottom end of said door opening, said door system comprising a sliding door displaceable between open and closed positions for selectively closing said door opening, a stairwell platform displaceable between a retracted position for clearing said stairwell and an extended position for covering said stairwell, and a threshold extending outwardly from an outer surface of said sliding door substantially at said vehicle floor level, said threshold being releasably and slidably connected to said sliding door for co-linear movement as a single unit with said sliding door between said open and closed positions when said stairwell platform is in said retracted position thereof, while remaining stationary in a functional position when said stairwell platform is in said extended position thereof for allowing high level boarding by providing a continuation of said stairwell platform.
- 2. A door system as defined in claim 1, wherein said threshold is disconnected from said sliding door in response to a displacement of said stairwell platform to said extended position thereof.
- 3. A door system as defined in claim 1, wherein said threshold is slidably connected to said sliding door, and wherein a retainer is provided for selectively keeping said threshold securely in place while said sliding door is displaced to said open position thereof.
- 4. A door system as defined in claim 3, wherein a latch is provided for selectively securing said threshold to said sliding door.
- 5. A door system as defined in claim 4, wherein said retainer is adapted to act on said latch to disconnect said threshold from said sliding door when said stairwell platform is in said extended position thereof for allowing high level boarding.
- 6. A door system as defined in claim 4, wherein said latch is mounted to said threshold and is normally urged to a door engaging position in which said threshold is secured to said sliding door via said latch.
- 7. A door system as defined in claim 6, wherein said retainer is integral to said stairwell platform and adapted, upon positioning of said stairwell platform to said extended position thereof, to disengage said latch from said sliding door in order to disconnect said threshold from said sliding door, and at the same time retain said threshold in said functional position thereof, thereby allowing said sliding door to move independently of said threshold.
- 8. A door system as defined in claim 7, wherein said latch is pivotally mounted to said threshold and provided with an engaging portion for engagement with a catch provided on said sliding door, said latch being normally spring biased in engagement with said catch, and wherein said retainer includes an abutment surface defined on said stairwell platform for contacting and pivoting said latch in a selected direction to displace said engaging portion of said latch out of engagement with said catch when said stairwell platform is displaced to said extended position thereof.
- 9. A door system for a railway vehicle having a door opening and a stairwell extending downwardly from a vehicle floor level to a bottom end of said door opening, said door system comprising a sliding door displaceable between open and closed positions for selectively closing said door opening, a stairwell platform displaceable between a retracted position for clearing said stairwell and an extended position for covering said stairwell, and a threshold extending outwardly from an outer surface of said sliding door substantially at said vehicle floor level, said threshold being adapted to jointly move as a single unit with said sliding door between said open and closed positions and to be made stationary in a functional position thereof by engagement of said threshold with a retainer upon positioning of said stairwell platform to said extended position thereof, whereby said sliding door may be displaced independently of said threshold to said open position thereof for allowing high level boarding.
- 10. A door system as defined in claim 9, wherein said threshold is slidably mounted on a rail secured to said sliding door.
- 11. A door system as defined in claim 10, wherein a latch is provided for selectively securing said threshold to said sliding door.
- 12. A door system as defined in claim 11, wherein said retainer is adapted to act on said latch to disconnect said threshold from said sliding door when said stairwell platform is in said extended position thereof for allowing high level boarding.
- 13. A door system as defined in claim 11, wherein said latch is mounted to said threshold and is normally urged to a door engaging position in which said threshold is secured to said sliding door via said latch.
- 14. A door system as defined in claim 13, wherein said retainer is integral to said stairwell platform and adapted, upon positioning of said stairwell platform to said extended position thereof, to disengage said latch from said sliding door in order to disconnect said threshold from said sliding door, and at the same time retain said threshold in said functional position thereof, thereby allowing said sliding door to move independently of said threshold.
- 15. A door system as defined in claim 14, wherein said latch is pivotally mounted to said threshold and provided with an engaging portion for engagement with a catch provided on said sliding door, said latch being normally spring biased in engagement with said catch, and wherein said retainer includes an abutment surface defined on said stairwell platform for contacting and pivoting said latch in a selected direction to displace said engaging portion of said latch out of engagement with said catch when said stairwell platform is displaced to said extended position thereof.
US Referenced Citations (9)
Foreign Referenced Citations (1)
Number |
Date |
Country |
2234281A |
Jan 1991 |
GB |