[0001] The present invention relates to a sliding door system for an elevator.
[0002] Elevator doors can be roughly divided into turning doors and sliding doors on the
one hand and car doors and landing doors on the other hand.
[0003] Turning doors, which, in view of safety and traffic demands, are by far the worst
solution in many respects, have been traditionally used in the Nordic countries in
the elevators of accommodation units, mainly for reasons of space and economy. A characteristic
feature of modern turning door solutions is that doors are only provided in the shaft
wall while the traditional gates serving as car doors have been left out. Besides
the safety risk - although it can be minimized e.g. by making the doors as smooth
as possible - this means in practice that the doors are opened manually, require plenty
of turning space and are slow in operation.
[0004] Among the worst drawbacks of sliding doors are the facts that they require a wider
elevator shaft than would otherwise be necessary to allow the landing doors to be
pushed aside, and that both landing doors and car doors have to be provided with separate
automatic mechanisms which make them very expensive as compared to ordinary turning
doors. In order to overcome these drawbacks there has been proposed that each floor
level is provided with one or more sliding doors which, relative to the elevator shaft,
are located on the external side of the landing door opening. That means in other
words that the elevator's sliding doors on the floor levels are placed like turning
doors of known construction, not inside the elevator shaft like conventional sliding
doors. This arrangement offers several advantages:
- The elevator doors can be provided with the same safety equipment as conventional
sliding doors, e.g. with photocells, mechanical or electrical safety edges on the
front surfaces, radar, etc.
- The doors are easier to handle e.g. for handicapped persons or children.
- The arrangement allows mechanical door actuation (which would be unthinkable, in
the case of corresponding turning doors), resulting in shorter door operation times
and therefore faster elevator traffic.
- The arrangement makes it possible to reduce the cross-sectional area of the elevator
shaft since no part of it is occupied by the door and its mechanisms.
[0005] Furtheron it has been proposed that the sliding doors on the floor levels are actuated
by a power means which is mounted on the elevator car and engages the respective door
when the elevator stops at a floor level.
[0006] The object of the present invention is to provide simple and light actuating means
for actuating the respective sliding door located on the external side of the landing
door opening.
[0007] The invention is characterized in that the power means on the elevator car consists
of a motor with a pulley or sprocket drive, comprising at least one element designed
to engage a rope or equivalent connected to the sliding doors so that the door is
opened and closed by driving the belt or chain round the wheels of the pulley or sprocket
drive through a certain distance.
[0008] Within the scope of the invention it is also possible to provide some floors with
separate means for door actuating.
[0009] A preferred embodiment of the sliding door system of the invention is characterized
in that the elevator car is provided with a gate, a light sliding door or equivalent,
which can be pushed aside manually or mechanically when passengers enter or leave
the car.
[0010] In this way, the same level of safety is achieved as in the case of conventional
sliding door systems. The elevator car can be provided with a collapsible gate or
preferably with a light sliding door of a segmental construction, which can be so
designed that it will take up but very little space and, when opened, is pushed aside
into a space which is otherwise useless, e.g. along the external sides of the car
walls or between its inner and outer walls.
[0011] The features characteristic of the rest of the embodiments of the invention are presented
in the claims to follow.
[0012] In the following, the invention is described in detail with reference to the drawings
attached, wherein:
Figs. 1a-1c present elevator doors constructed by known techniques.
Figs. 2a-2c present a sliding door system with doors on the floor levels only.
Figs. 3a-3b present a sliding door system with doors on the floor levels as well as
on the elevator car.
Fig. 4 presents a diagram of the means used for actuating the landing door.
Fig. 5 shows the elevator door of Fig. 4 in front view.
Fig. 6 represents an elevator system using different types of door.
[0013] Figures 1a-1c show three elevator doors of known construction, Fig.1a representing
an elevator provided with an ordinary turning door 1, Fig.1b an elevator with automatic
double sliding doors 2,3 both on the elevator car and in the shaft wall, and finally
Fig.1c a variation of the previous construction in which all the doors 4,5 move sideways
in the same direction. The, drawbacks of these constructions have already been described,
and special attention should be paid to the placement of the doors in Figs. 1b and
1c when comparing with the constructional alternatives of Figs. 2a-c.
[0014] Fig. 2a shows a sliding door system with two sliding doors 6 of light construction
which move in opposite directions. Relative to the elevator shaft 7, the sliding doors
6 are placed on the external side of the landing door opening 8, and they are operated
by a power means mounted on the elevator car 9 (see Fig.4) which engages and actuates
the doors when the elevator stops at the landing. From the safety point of view,
the essential thing about this construction is that the doors should be made flat
and smooth, e.g. in accordance with the regulations concerning turning doors. The
door opening of the elevator car is provided with the same safety equipment as conventional
sliding doors, e.g. with photocells and mechanical or electrical safety edges on the
front faces of the doors.
[0015] Fig. 2b shows a variation of the system in Fig. 2a, with only one door 10 moving
sideways (cf. Fig. 1c).
[0016] Fig. 2c presents another sliding door system resembling the one in Fig. 2a and having
two sliding doors movable in opposite directions, each door consisting of two or
more vertical laminar segments joined together to make the door lighter and more flexible.
[0017] Figs. 3a-3b shows an embodiment of the sliding door system with doors provided both
on the elevator car and on each floor level. The car door is a gate, a light sliding
door or equivalent, which is pushed aside manually or mechanically when a passenger
enters or leaves the car. In Fig. 3a, the landing door 12 corresponds to the solution
in Fig. 2b while the elevator car is provided with a light sliding door 14 or equivalent,
which is pushed aside (as indicated by the broken lines) when a passenger enters or
leaves the car. This type of gate, which may be a collapsible gate or, as shown in
the present case, a light sliding door consisting of laminar segments, can be so constructed
that it will only take up a minimal space and, in the case shown, is pushed aside
e.g. along the external side of the car walls.
[0018] Fig. 3b shows another embodiment of the sliding door system resembling the one in
Fig. 3a, in which the landing door opening is provided with two sliding doors 15 movable
in opposite directions and the elevator car 17 similarly with two sliding doors 16
movable in opposite directions. In this case, the sliding doors 15 at the landings
correspond to the solution shown in Fig. 2a, and the light sliding doors 16 are similarly
pushed sideways in opposite directions (as indicated by the broken lines) along the
external side of the car walls when passengers enter or leave the elevator.
[0019] Fig. 4 shows a schematic diagram of the door actuating means used in the sliding
door system exemplified by Fig. 2b. The basic idea is that the door 10, which is provided
with wheels or other sliding elements 24 placed at its lower edge, is driven bY a
motor 30 which is mounted on the elevator car 9. The motor drives the upper one of
a pair of pulleys of sprockets 18 for a V-belt or chain 19 running around them. When
the car arrives at a floor level 23, the chain is driven anti-clockwise so that a
catch 22 on the upper wheel 18 grips a rope 21 connected to the elevator door 10 via
a deflecting wheel 20 and other requisites (see Fig. 5). As the catch 22 then moves
continuously downward through a preset distance, it pulls the rope with it through
an equal distance, thus causing the elevator door 10 to open by sliding leftwards
in Fig. 5.
[0020] In this way, the door opening mechanism is actuated by the motor 30 on the elevator
car every time when the car 9 stops at a floor level. Thus, a light door construction
is achieved and the space requirement is minimized without losing any of the advantages
provided by an automatic landing door.
[0021] By examining Fig. 5 and identifying in it the door 10, deflecting pulley 20 and
rope 21 shown in Fig. 4, and the door suspension rail 25, the rope lug 27 on the door
and the deflecting pulley 26 fixed to the wall, it is easy to see that when a downward
pull (indicated by the arrow) is applied to the rope 21, the door is caused to move
leftwards in the figure, thereby revealing the doorway of the elevator car. A safety
stop 28 prevents the door from being opened when the car is not present at the landing.
The closing of the door can be implemented using a return spring, a counterweight
etc., which counteracts the opening motion of the door. When opened, the door preferably
slides into a space behind a protective cover 29 provided on the opposite side of
the door opening, so that the door cannot hit or squeeze anything or anybody when
it is opened.
[0022] Obviously, a gate or door possibly provided on the elevator car itself can be driven
by the same motor 30 as the landing door to open them both simultaneously. Alternatively,
the light car door may be of a manually operated design. It is also obvious that the
idea of the invention allows some of the sliding doors on the floor levels to be provided
with their own power means for mechanical actuation.
[0023] Fig. 6 shows a view of the floor levels of a building, illustrating how, by virtue
of the invention, different floors can have different door systems for the same elevator
car.
[0024] Reference number 30 identifies an ordinary sliding door, number 31 a dual sliding
door with the doorway in the middle, number 32 an ordinary turning door with a door
closer, and number 33 a typical basement landing door without an automatic closing
mechanism. In practice, the same type of sliding doors are used as far as possible,
but the invention offers flexibility in the choice of door type and suspension arrangements
depending on the space available on the floor level in question, its use and other
factors.
1. A sliding door system for an elevator, in which at least some of the floors are
provided with one or more sliding doors (6;10;11;12;15) which, relative to the elevator
shaft (7), are located on the external side of the landing door opening, and in which
the sliding doors (6;10;11;12;15) on the floor levels are operated by a power means
(18,19,30) mounted on the elevator car and engaging the respective door (10) when
the elevator stops at a floor level (23), characterized in that the power means on the elevator car consists of a motor with a pulley or
sprocket drive (18,19) comprising at least one element (22) designed to engage a rope
(21) or equivalent connected to the sliding doors (10) so that the door (10) is opened
and closed by driving the belt or chain (19) round the wheels (18) of the pulley or
sprocket drive (18,19) through a certain distance.
2. Sliding door system according to claim 1, characterized in that the elevator car (13;17) is provided with a gate, a light sliding (14;16)
door or equivalent, which can be pushed aside manually or mechanically when passengers
enter or leave the car.
3. Sliding door system according to claim 2, characterized in that the light sliding door (14;16) consists of a number of vertical laminar segments
turnable relative to each other, enabling the sliding door to be pushed into spaces
provided for this purpose in the side walls of the elevator car.
4. Sliding door system according to any one of the preceding claims, characterized in that, when opened, the sliding door slides into a protective cover (29).
5. Sliding door system according to any one of the preceding claims, characterized in that at least one of the floor levels is provided with one or more doors of a
different type, e.g. turning doors (32,33).