The present invention relates to an elevator car with a car roof which is lowerable into the passenger compartment and which in the lowered position serves for maintenance personnel as a maintenance platform for the performance of maintenance and checking operations, as well as to a method for maintenance of components arranged in the elevator shaft of an elevator installation.
It is known that maintenance operations at elevator components arranged in the elevator shaft are undertaken by a maintenance person standing on the car roof of the elevator car. The elevator car is for this purpose movable in the entire elevator shaft by means of an inspection control. During this process it is absolutely necessary to ensure, through additional technical measures, a safety spacing between the car roof of the elevator car and the shaft roof or between the car roof and elevator components installed in the region of the shaft roof, so as to avoid the possibility of the maintenance person being trapped.
JP 09263372 discloses a solution which ensures that such a safety spacing is kept. It is proposed therein to so design a elevator car that its car roof is lowerable into the passenger compartment so that it forms a maintenance platform from which the maintenance person carries out inspection or repair operations at elevator components fixed in the elevator shaft. Through lowering of the car roof it is achieved that the said safety spacing is guaranteed without special safety devices, such as, for example, abutment buffers pivotable into the car travel path or an additional switching device, which forms a downwardly displaced upper electrical path limitation, being required.
The lowerable car roof disclosed in JP 09263372 and serving as a maintenance platform has certain disadvantages which are briefly described in the following:
The car roof is suspended at four pull means in the form of wire cables which are led over deflecting rollers to a cable drum and able to be wound up on and unwound from this. The pull means are guided in rectilinear sections between the cable drum, which forms a part of a drive device for the car roof, and the fastening points of the pull means in the region of the corners of the car roof, wherein the horizontally oriented pull means sections extend above the car roof in the region of the surface of the car roof serving as maintenance platform. Such an arrangement of the pull means carrying the car roof has, on the one hand, the disadvantage that these restrict the area of the car roof, particularly the edge region thereof, which can be walked on and form obstacles to the accessibility of elevator components in the elevator shaft to be maintained. In that case the pull means freely extending in the compartment also cause tripping accidents of the maintenance personnel. On the other hand, the pull means arranged freely in the compartment and extending rectilinearly obstruct optimum arrangement of elevator components in the region of the car roof, for example the optimum arrangement of an upper yoke of a car frame, of terminal boxes, of roof hatches or roof railings.
The present invention has an object of proposing an elevator car and a maintenance method of the kind stated in the introduction which do not have the stated disadvantages of the equipment cited as state of the art. In particular, an elevator car with a lowerable car roof as a maintenance platform shall thus be created in which a drive device for the car roof does not have pull means which necessarily extend rectilinearly and freely in the compartment and in that case restrict the area of the car roof which can be walked upon, represent a risk of accident and prejudice optimum arrangement of elevator components in the region of the car roof. Moreover, the solution shall be space-saving and economic.
The present invention is based on the concept of eliminating the aforesaid problems with the pull means, which are executed as open wire cable connections, of the drive device for the car roof in that the car roof is lowered and raised with the help of Bowden pulls.
The advantage of use of Bowden pulls for the drive device of the car roof consists, in particular, in that the arrangement and the course of the pull means required between the drive device and the car roof and the arrangement of the drive device moving the pull means are almost completely freely selectable without creation of additional costs by comparison with a solution having shortest possible, rectilinearly arranged pull means. The Bowden pulls require a minimum of installation space and are so arranged that they do not form any obstacles and any risk of accident for the maintenance personnel.
According to a particularly simple embodiment of the present invention, the Bowden pulls comprise flexible casing tubes and pull means guided therein, wherein respective first ends of the pull means are connected with the lowerable car roof and the corresponding ends of the flexible casing tubes are fixed to car components arranged in the upper region of the elevator car to be immovable.
In the case of a particularly stable form of embodiment of the present invention the car components arranged in the upper region of the elevator car to be immovable are present in the form of a roof frame connected with the upper edges of the side walls.
In advantageous manner the pull means are connected in the region of the second ends thereof with a drive device, wherein a movable drive part of the drive device so co-operates with the pull means in the region of the second ends thereof that a movement of the drive part produces a longitudinal displacement of the parts of the pull means leading to the car roof, wherein the ends, which correspond with the second ends of the pull means, of the flexible casing tubes are fixed in the region of the drive device to a component immovable relative thereto.
In order to save costs, the flexible casing tubes can have interruptions, wherein the ends, which are associated with the interrupt locations, of the casing tubes are fixed to the elevator car by means of retaining members and the pull means extend rectilinearly between the interrupt locations.
In the case of a particularly space-saving embodiment of the present invention the drive part, which moves the pull means, of the drive device is linearly displaceable, wherein the linearly displaceable drive part so acts on the pull means that the first ends thereof allow the car roof to lower or raise it.
Advantageously the drive device comprises a threaded spindle or a cogged belt drive or a chain drive, which serves the purpose of linearly displacing the drive part of the drive device.
A further reduction of the space requirement of the drive device is achieved in that the drive device comprises a drive input shaft with a coupling member by way of which a maintenance person causes, with the help of a crank or an electrically operated torque motor, movement of the drive part moving the pull means or displacement of the linearly displaceable drive part of the drive device.
In order to be able to produce the requisite stroke travel of the car roof with a given maximum installation length of the drive device the linearly displaceable drive part in the drive device so co-operates with the pull means in the region of the second ends thereof that displacement travels result in the sections, which lead to the car roof, of the pull means and thus a stroke travel of the car roof which correspond at least with twice the displacement travel of the linearly displaceable drive part.
A marked operating friendliness of the device according to the present invention is achieved in that the drive device is mounted in the lower region of a door transom of a car door and can be actuated by a maintenance person from the floor of a floor by hand or by means of electrically operated torque motor when the elevator car is positioned in the region of this floor and the shaft door and the car door are opened.
In order that the car roof during its lowering or raising movement does not come into contact with the inner sides of the car walls and in order to impart to the car roof, which serves as the maintenance platform, sufficient resistance to horizontal movements the elevator car is provided with at least one scissors mechanism which connects the car roof with the region of the roof frame of the elevator car to be vertically displaceable.
An additional improvement in the resistance to horizontal movements of the car roof is achieved in that the car roof lowered to its intended work level is connected with the region of the roof frame of the elevator car by at least one pair of flexible tension struts arranged crosswise and in a plane parallel to a car wall.
According to an advantageous embodiment of the present invention the stroke force required for raising the car roof is reduced in that at least one relief device, which bears a part of the weight of the lowerable car roof with the help of a biased spring, is present in the region of the roof frame of the elevator car.
A particularly preferred embodiment of the relief device comprises a cable drum, a relief cable winding up onto and unwinding from this cable drum and connected with the car roof, and a torsion spring driving the cable drum.
For increase in the functional reliability of the lowerable car roof there is present in the region of the roof frame of the elevator car at least one locking device preventing an unintended sinking of the lowerable car roof.
An advantageous development of the present invention consists in that the at least one locking device is unlockable means of at least one unlocking Bowden pull, wherein a pull means of the unlocking Bowden pull is connected with a turntable which is present at the drive device and which has to be manually displaced so that the crank or the torque motor can be coupled to the drive input shaft of the drive device. An automatic unlocking of the locking device prior to commencement of lowering of the car roof is thus guaranteed.
In a particularly advantageous embodiment of the present invention there is pivotably mounted on the lowerable car roof of the elevator car a climbing ladder which when the car roof is lowered to approximately half the height of the passenger compartment is pivotable down from this so that a maintenance person can go from the respective floor through the open shaft and car doors and by way of the pivoted-down climbing ladder onto the lowered car roof.
The climbing ladder is particularly economic, weight-saving and easily handled if it comprises a single central ladder post having a plurality of telescopically extensible segments.
A particularly advantageous embodiment of the elevator ladder results when each segment of the ladder post comprises a single rung, wherein a locking mechanism, by which each time two telescopic segments of the centre post can be mutually locked in the extended state and manually unlocked for pushing into one another, is present in the region of each rung.
The above, as well as other, advantages of the present invention will become readily apparent to those skilled in the art from the following detailed description of a preferred embodiment when considered in the light of the accompanying drawings in which:
The Bowden pulls 6, of which each comprises a flexible casing tube 8, which is continuous or formed by several sections, with the pull means 7 guided therein, connect the lowerable car roof 2 with a drive device 10 which is fastened below a part of the roof frame 4 at the car door side, i.e. in the region of the door transom of the car door. The drive device 10, described in detail below, has the task of inducing all the pull means 7, which lead to the car roof 2, to synchronous longitudinal movements which produce a parallel lowering or raising of the car roof 2. Each of the pull means 7 is in that case guided at least partly in the flexible casing tube 8 up to a support point 9 at the roof frame, which lies vertically above a fastening point of the pull means 7 at the lowerable car roof. The casing tube 8 of each Bowden pull preferably runs without interruption from the drive device 10 to the support point 9 at the roof frame 4, where it is fixed. However, in certain cases it can be advantageous to divide the casing tube 8 up into two or more sections 8.1 spaced apart in longitudinal direction. In the case of interrupted casing tubes 8.1 the ends, which are associated with the interruption, of the casing tubes are non-displaceably fixed to the elevator car, preferably by means of retaining members 12 at the roof frame 4. The associated pull means 7 always extends without interruption from the drive device 10 through the continuous or interrupted casing tube 8, 8.1 via the support point 9 at the roof frame to the fastening point, which is disposed vertically thereunder, at the car roof, wherein it can always run only rectilinearly between the ends, which are associated with an interruption, of the casing tubes 8.1.
Each of the Bowden pulls 6 can in that case—for the purpose of circumventing obstacles, for aesthetic reasons or so as not to form an obstruction for a maintenance person standing of the car roof—be arranged in innumerable variants and, as well, be bent in all desirable directions. In special cases, for example for a deflection with obligatory small deflection radius, it can be useful to use a deflecting roller instead of a deflection of the pull means by means of casing tube, as is illustrated by way of a deflecting roller 13.
In order to ensure that the car roof 2 during its lowering and raising movement does not come into contact with the usually scratch-sensitive car walls or with the keyboard of a control panel and, in addition, has sufficient horizontal stability as maintenance platform the car roof 2 is, as recognizable in
The scissors arms can also serve for guidance of a power cable ensuring the feed of electrical energy from the elevator car to the lowerable car roof so as to supply, for example, the lighting fixtures of the illuminated roof. Such a power cable can be fixed to, for example, each section of a scissors arm, wherein the power cable forms, in the region of the transition between two mutually displaceable sections, a hanging loop so as to bridge over the mutual displacement of the scissors arms.
An additional horizontal stabilization of the lowered car roof 2 is achieved by a pair of tension struts 17 which are arranged crosswise in a plane parallel to a car wall and are flexible in bending, but longitudinally stiff and which connect the car roof 2 with the roof frame 4. With maximum lowering of the car roof the tension struts 17 are tensioned, whereby the latter, in co-operation with the pull means 7 of the Bowden pulls carrying the car roof, suppress horizontal movements of the car roof 2 directed parallel to the car wall.
The illustrated relief device 18 comprises a cable drum 18.2 which is mounted on an elongated axle 18.1 and on which a relief cable 18.3 connected with the car roof 2 can be wound up or unwound in the manner of a thread. A helical spring 18.4 coupled by one end thereof with the cable drum 18.2 and by the other end thereof with a fixing part 18.5 is guided on the axle. The helical spring 18.4 is biased as a torsion spring, wherein it exerts a torsional moment on the cable drum 18.2 so that there results in the relief cable 18.3 an upwardly directed tension force which counteracts the weight force of the car roof 2. Advantageously a respective such relief device 18 is mounted on each of two opposite sides of the elevator car 1.
The drive device 10.1 substantially comprises the following components:
the drive part 10.1.6, which is linearly displaceable with the help of the drive spindle 10.1.1 and which is guided at the roof frame element 4.1, with pull means deflecting rollers 10.1.7 for movement of the pull means of the Bowden pulls 6 leading to the car roof.
The task of the drive device according to
It is readily recognizable that in the case of the drive arrangement illustrated in
The drive device 10.2 substantially comprises the following components:
The task of the drive device according to
A chain drive can also be used instead of the cogged belt drive 10.2.1.
The bevel gear 10.1.3 for manually actuated driving of the drive spindle 10.1.1 of the drive device, which is described by
The drive device 10.1 arranged in the region of the door transom of the car door is concealed by the cover 10.1.9 having a first opening 10.1.9.1 through which the hand crank 10.1.8 can be coupled with the drive input shaft 10.1.3.1. In order to hinder unauthorized actuation of the drive device this is equipped with a turntable 10.1.10 which is arranged between the cover 10.1.9 and the drive input shaft 10.1.3.1 and which is pivotably fastened to a U-shaped carrier section 10.1.13 by way of a rotational axle 10.1.10.1. In its self-centered basic setting the turntable blocks, by its blocking blade 10.1.10.2, introduction of the coupling member of the hand crank 10.1.8. In order for the maintenance person to be able to couple the hand crank with the drive input shaft 10.1.3.1 that person must introduce a screwdriver-like tool vertically into a slot-shaped second opening 10.1.9.2 and into the bore of a universal joint head 10.1.12 arranged vertically above the opening. Through pivoting of the tool in the direction predetermined by the slot-shaped second opening the shank of a tool 10.1.11 acts against an actuating runner 10.1.10.3 at the turntable 10.1.10, whereby the turntable is pivoted about its rotational axis 10.1.10.1 and its blocking blade 10.1.10.2 frees access to the drive input shaft 10.1.3.1. This setting of the turntable is illustrated in
The movement of the turntable 10.1.10 produced for coupling the hand crank 10.1.8 is used in order to actuate, by way of unlocking Bowden pulls 10.1.12, the locking pawls of at least two locking devices preventing unintended lowering of the car roof. Such a locking device is illustrated in
It will be obvious that the afore-described safety devices are also usable with a drive device with cogged belt drive or chain drive.
As already explained in connection with the safety devices, which were illustrated in
A so-called helix cable ensuring the feed of electrical energy from the elevator car 1 to the lowerable car roof 2 so as to supply, for example, the lighting fixtures 2.3 of the car roof is illustrated by reference numeral 30 in
In accordance with the provisions of the patent statutes, the present invention has been described in what is considered to represent its preferred embodiment. However, it should be noted that the invention can be practiced otherwise than as specifically illustrated and described without departing from its spirit or scope.
Number | Date | Country | Kind |
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05107904.4 | Aug 2005 | EP | regional |