ELEVATOR PIT MAINTENANCE DEVICE AND METHOD OF PIT MAINTENANCE

BACKGROUND

The invention relates to an elevator pit maintenance device. The invention further relates to a method of removing articles from an elevator pit by using an elevator pit maintenance device.

In many elevator pits rubbish of various kinds accumulates over time. This is particularly true when a building is under construction or when an elevator system is being installed in an elevator hoistway. When a building is in regular use, cleaning the floors in front of the landing doors in the individual stories and cleaning the floor in an elevator car quite often results in pieces of rubbish falling through the small gap between the landing door at the elevator car. Moreover, people sometimes drop unintentionally objects through such gap, for example keys. And there are even people who throw intentionally objects through said gap in order to dispose of them.

All of the rubbish and/or objects that fall through the small gap accumulate on the pit bottom. The site of the accumulated rubbish and/or objects is particularly unpleasant in the case of panoramic elevators or elevators having a transparent glass wall hoistway that enables people to see into the pit from outside. Apart from such a situation, the rubbish and/or objects accumulated in the elevator pit may create a risk of fire and, depending on the nature of the rubbish and/or objects, result in a bad smell in the elevator shaft.

In light of the foregoing problems, the rubbish and/or objects that have accumulated in the elevator pit have to be removed from time to time. Conventionally, mechanics clean the elevator pit from time to time. For doing this, the elevator must be stopped, the mechanic must go into the narrow dirty pit and put the rubbish into a sack, by using his hands and/or a spade and/or a broom. Normally dust, which may be inhaled by the mechanic, is raised by such way of cleaning. Moreover, such cleaning is not only unpleasant, it may even be hazardous for the mechanic, taking into account that there might be hazardous

substances among the rubbish and hazardous objects such as used syringes. Moreover, the cleaning is time-consuming and therefore expensive. Finally, in light of the foregoing concerns, a mechanic may have a tendency to refrain from doing the cleaning and to hope that the cleaning might instead be done by another mechanic when the next maintenance is due.

In light of the foregoing, the invention aims to provide a simple and inexpensive mechanical device that may facilitate maintaining the elevator pit and removing rubbish and other objects therefrom.

Another aim of the present invention is to reduce the time required for a mechanic to maintain the elevator pit and to remove rubbish and other objects therefrom, as well as to make the job of cleaning the elevator pit more pleasant for the mechanic.

SUMMARY

An embodiment of the present invention addresses an elevator system that includes, among other possible things: a hoistway having a pit; an elevator car configured to move upwardly and downwardly in the hoistway above the pit; a counterweight connected to the car and/or to a car frame; and an elevator pit maintenance device. The elevator pit maintenance device includes: a base component sized to cover at least a portion of the pit; and a lifting component attachable to the car, the car frame, and/or the counterweight and configured to allow the base component to be lifted by the car, car frame, and/or counterweight when a lifting force is applied to the lifting component.

In some embodiments of the invention, the elevator pit maintenance device may be in the form of a net that is designed to be placed in an elevator pit to cover at least a portion of the pit bottom area and to prevent objects that have larger sizes than the net openings, from falling onto the covered area of the pit bottom. In such embodiments, the maintenance net may include a net component for covering the portion of the pit bottom area and a lifting component allowing the maintenance net to be lifted by applying a lifting force to one or more lifting location(s) of the lifting component. The lifting component may include a plurality of strands attached to the net component at respective attachment locations

substantially at the perimeter of the net component and extending to said one or more lifting locations.

The elevator pit maintenance device by itself, as described herein, i.e. without being part of the elevator system, constitutes an invention and is a further subject-matter of the present application.

Another embodiment of the present invention addresses a method of cleaning an elevator pit of an elevator hoistway. This method includes, among other possible steps: placing an elevator pit maintenance device into the elevator pit so as to cover at least a portion of the pit; accessing the elevator pit maintenance device through an opening of the elevator hoistway; attaching the elevator pit maintenance device to an underside of an elevator car, an elevator car frame, and/or a counterweight connected to the car and/or car frame; lifting the elevator pit maintenance device by raising: (a) the elevator car and/or car frame; or (b) the counterweight; removing the elevator pit maintenance device from the hoistway through an opening of the elevator hoistway; and removing objects, if any, in the elevator pit maintenance device.

In some embodiments of the present invention, the method may include placing a net into the elevator pit so as to cover at least a portion of the pit bottom area; accessing the net through a door opening of a landing door of the elevator shaft; lifting the net and taking it out of the elevator shaft through a door opening of a landing door of the elevator shaft; removing objects, if any, lying on the net; and placing the net back into the elevator pit so as to cover at least a portion of the pit bottom area.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only, and are not restrictive of the invention as claimed. The invention and preferred optional features of the invention are now elucidated by means of a non-limiting embodiment of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features, aspects, and advantages of the present invention will become apparent from the following description, appended claims, and the

accompanying exemplary embodiments shown in the drawings, which are hereafter briefly described.

Fig. 1 is a perspective view of an elevator pit maintenance device placed on the bottom of an elevator pit;

Fig. 2 is a perspective view of the maintenance device of Fig. 1 , but in a state in which rubbish has fallen onto the maintenance device and the maintenance device has been lifted in order to remove the rubbish from the elevator pit.

DETAILED DESCRIPTION

Efforts have been made throughout the drawings to use the same or similar reference numerals for the same or like components.

Fig. 1 shows the pit of an elevator hoistway and in particular a pit bottom 2. The lower ends of two elevator car guide rails 4 and the lower ends of two counterweight guide rails 6 stand on the bottom 2. The bottom 2 is in most cases of concrete.

An elevator pit maintenance device 8 has been placed in an essentially flat condition on the pit bottom 2. Although the elevator pit maintenance device 8 may, in some embodiments, include a sheet that may be formed of materials such as canvas, plastic, foil, etc., in other embodiments, the elevator pit maintenance device 8 may include a net. By using a net (or other porous material) for the elevator pit maintenance device 8, liquids that fall onto the elevator pit maintenance device 8 will not be raised with the elevator pit maintenance device 8 when the elevator pit maintenance device 8 is removed from the hoistway, as later described. For this reason, the elevator pit maintenance device 8 will, in the following paragraphs that reference Fig. 1 , be referred to as "net device 8".

The net device 8 comprises a base (or net) component 10 and a lifting component 12. The base component 10 comprises a set of parallel first strands running in a first direction and a set of parallel second strands running in a second direction that is at an angle relative to the first direction. The strands define openings 14 between them which are, in the present example, square-

shaped and have a size of, e.g., 5 x 5 mm. Of course, the number of strand directions and the number of strands (and, therefore, the size of the openings) is variable depending on the needs of a particular device 8 embodiment.

The base component 10 as a whole may, as shown, have a rectangular shape, fitting - in one direction from a first wall of the elevator shaft to the opposed second wall thereof, and - in another direction - between the elevator car guide rails 4.

The base component 10 further comprises a reinforcement 16. The reinforcement 16 essentially extends around the perimeter of the base component 10 but at a slight distance from the actual perimeter 18 thereof (hereinafter the region between and including the actual perimeter 18 and the reinforcement 16 is to be considered the "perimeter" of the base member 10).

Many materials are suitable to be used for the strands of the base component 10, in particular plastics material, fibre reinforced plastics material, strands made of fibres, metallic ropes, preferably glass fibre strands jacketed by plastics material. Similarly, many materials are suitable to be used for the reinforcement 16 such as plastics material, fibre reinforced plastics material, strands made of fibres, metallic ropes. All materials used for the net component 10 may be fireproof.

The lifting component 12 of the net device 8 comprises, as its main parts, a plurality (e.g., four) lateral stands 20 (which may be radially arranged, as shown) and a lifting element 22. Each lateral strand 20, which is affixed to the reinforcement 16 of the base component 10 at distal ends thereof, runs from a corner area of the lifting component 12 to at least one (e.g., central) lifting location 24 of the lifting component 12. The lateral strands 20 are connected to each other at the lifting location 24.

The lifting element 22 of the lifting component 12 is connected to the lateral strands 20 at the lifting location 24. A free end 25 (which is shown in Fig. 1 as being close to the perimeter 18 of the base component 10) of the lifting element 22 is equipped with an engagement member 26 such as a hook (shown in Fig. 1 ), a ring 28 (shown in Fig. 2), a clasp, or other suitable member that is configured to engage a corresponding engagement member (not shown). Such a corresponding engagement member may be, for example, positioned on the

bottom of an elevator car, car frame, and/or counterweight (hereinafter collectively "car).

Many materials are suitable to be used for the lateral strands 20 and the lifting element 22. Similar to the thinner strands of the net component 10, preferred materials are plastics material, fibre reinforced plastics material, strands made of fibres, metallic ropes. All materials used for the net component 10 and for the lifting component 12 may be fireproof.

After an elevator maintenance device 8 has been used for some period of time, there will be an accumulation of rubbish and other objects on the device 8. In order to clean the elevator pit, a mechanic moves the elevator car 30 of the elevator system upwardly to such an extent that it is positioned at such a height that the lowest landing door may be opened to allow access into the elevator pit. The mechanic uses a suitable tool (not shown), for example a bar with a hook at one of its ends, and moves such end down into the elevator shaft until it engages with the engagement member 26 of the lifting element 22. The mechanic then has two options. First, if the lifting element 22 is long enough to reach the car directly, the mechanic may, after obtaining the lifting element 22 by means of the tool, fastens the engagement member 26 of the lifting element directly to a corresponding engagement element on the underside of the car. Or, if the lifting element 22 is not long enough to reach the car, the mechanic may fasten an opposite end of the tool to the underside of the car. In either case, when the lifting element 22 is engaged (directly or indirectly) to the underside of the car, the mechanic then lifts, by raising the car, the lifting element 22.

If the lifting element 22 is engaged (directly or indirectly) to the underside of the car at a position substantially directly above the lifting location 24, the base component 10 will be raised substantially vertically. If, however, the lifting element 22 is engaged (directly or indirectly) to the underside of the car at a position that is closer to the door opening of the landing door from which the mechanic is accessing the pit bottom 2, the base component 10 will, when raised, swing toward the opening, thereby enhancing the mechanic's ability to reach the device 8 when the device 8 is raised to the door opening of the landing door. Regardless, the mechanic may not need to move himself into the elevator pit; in other words the mechanic can do the cleaning job while standing in the door opening of the open landing door.

It should be noted that, in cases in which the device 8 is in the form of a net, the present invention provides the further advantage. Specifically, any liquid flowing into the elevator pit will be able to flow through the net device 8 and onto the floor of the pit bottom 2. As a result, when the device 8 is lifted by means of the car, the liquid will not be raised with the rubbish or other objects in the base component 10 of the net device 8.

Fig. 2 shows the situation, when the net 8 has been lifted to such an extent that it is no longer in contact with the bottom 2 of the elevator pit. The provision of the lateral strands 20 has the effect that the base component 10 comes into a configuration somewhat like a sack when the device 8 is lifted. The risk that rubbish or other objects fall off sideways from the base component 10 is minimized by the reinforcement 16, which helps to stabilize the base component 10 when the device 8 is lifted. The device 8 in its configuration shown in Fig. 2 may be readily moved from back to front in Fig. 2 and through the open landing door. Then the device 8 may be turned upside down and emptied into a rubbish container. Thereafter, the device 8 (or a similar second device 8) may be thrown back onto the bottom 2 of the elevator shaft. Further, bar-like tools may be used to place the four corners of the base component 10 in the locations where they should be in order to re-create the situation shown in Fig. 1.

In many cases it is sufficient if the base component 10 has a width that is wider than the width of a landing door opening but not as well as the entire hoistway. Similarly, the depth of the base component 10 may only be 30-60% of the distance between the landing door opening and the opposite rear wall of the hoistway. This is so, because most of the rubbish and other objects falling into the elevator pit accumulate in a region which is relatively adjacent to the front wall of the elevator shaft along which the landing doors are provided. Such a smaller size of the base component 10 is also advantageous, if springs or other buffers to support the elevator car are arranged in an area between the elevator car guide rails 4. In order to leave such springs or other buffers free, one may work with two or more separate elevator maintenance devices 8, placed on the pit bottom 2.

The aforementioned discussion is intended to be merely illustrative of the present invention and should not be construed as limiting the appended claims to any particular embodiment or group of embodiments. Thus, while the present invention has been described in particular detail with reference to specific exemplary embodiments thereof, it should also be appreciated that numerous

modifications and changes may be made thereto without departing from the broader and intended scope of the invention as set forth in the claims that follow. For example, although the elevator pit maintenance device is described as a net, the device could also be, for example, a piece of nonporous fabric or canvass that may be intended to catch liquids. By way of another example, for elevator hoistways that have conventionally wide or deep configurations, more than one lifting location 24 may be provided; some of the lateral strands 20 may be connected to a first lifting location 24, and other lateral strands 20 may be connected to a second lifting location 24, etc.

The specification and drawings are accordingly to be regarded in an illustrative manner and are not intended to limit the scope of the appended claims. In light of the foregoing disclosure of the present invention, one versed in the art would appreciate that there may be other embodiments and modifications within the scope of the present invention. Accordingly, all modifications attainable by one versed in the art from the present disclosure within the scope of the present invention are to be included as further embodiments of the present invention. The scope of the present invention is to be defined as set forth in the following claims.