Patent Description:
Elevator systems typically include an elevator car suspended in a hoistway by a number of suspension ropes. To guide the elevator car in the hoistway, a number of guide rails are arranged in the hoistway, for example, from the top to bottom of the hoistway. The elevator car is connected to the guide rails via one or more guide shoes such that the elevator car follows a path defined by the guide rails as it moves through the hoistway. Further, in some elevator systems, a braking mechanism connected to the elevator car acts on the guide rails to slow and/or stop the elevator car in the hoistway.

The typical guide rail is a solid steel T-shaped rail. Such rail configurations are typically utilized because of their ability to withstand buckling and deflection during normal elevator operations and to withstand and loads applied during emergency braking. The typical rails, however, are heavy and bulky, with each rail typically weighing <NUM> or more pounds per linear foot and are typically installed in <NUM>-foot sections. Installation requires heavy equipment due to the weight of the rails, and is additionally difficult due to the constraints of installing the sections in the confined space of the elevator hoistway. The art would well receive a lighter weight, more easily installed guide rail which can withstand the operational and braking loads of the elevator system.

According to one aspect of the invention, a guide rail for an elevator system includes a base connectable with a hoistway of the elevator system and a web section connected to and extending from the base. A tip section is located at an end of the web section and is operably connectable to an elevator car of the elevator system. The base, the web section and the tip section are formed of one or more thicknesses of sheet metal material. The guide rail is configured such that braking forces applied to the guide rail by a braking mechanism successfully reduce the speed of the elevator car without resulting in failure of the guide rail.

<CIT> discloses an elevator car guide rail of an elevator, in which a plate-shaped iron plate is firstly bent to form a guide portion having an n-shaped tip, and the iron plate is continuously bent on both sides of the other end portion of the guide portion, and a core <NUM> is inserted into the inside of the head portion which actually serves as a guide among the guide portions. The core is spaced apart from the fixing portions by a predetermined distance. A plurality of fixing holes are formed in the guide portion. An engaging groove is formed at the center of one end of the guide portion in the longitudinal direction of the guide portion, and a projection is formed Also <CIT> discloses an elevator car guide rail made of sheet metal.

The present invention relates to a guide rail for an elevator system and an elevator system according to the appended claims.

In particular embodiments, the tip section may include a tip cavity disposed therein. Further, the tip section may include a stiffener disposed in the tip cavity to reinforce and provide rigidity to the tip section. Further, the stiffener may be substantially baffle- shaped.

Further, a filler material may be disposed in the tip cavity to reinforce and provide rigidity to the tip section. Further, the guide rail may be formed from a single piece of sheet metal. Further, the web section may comprise more than two thicknesses of sheet metal. Further, the tip section may comprise at least three thicknesses of sheet metal without gaps therebetween. Further, the guide rail may be formed in the hoistway from a sheet metal stock. Further, <NUM>. the guide rail may be formed in the hoistway by a process including one or more of rolling, punching and/or welding. Further, the braking forces may be applied to the guide rail at the tip section. Further, the braking forces may be applied to the guide rail at the web section.

According to another aspect of the invention, an elevator system includes an elevator car located in a hoistway and a guide rail extending along the hoistway and operably connected to the elevator car for guiding the elevator car along the hoistway. The guide rail includes a base connectable with the hoistway, a web section connected to and extending from the base, and a tip section located at an end of the web section and operably connected to the elevator car. The base, the web section and the tip section are formed of one or more thicknesses of sheet metal material. The elevator system includes a braking mechanism operably connected to the guide rail and the elevator car, the guide rail configured such that braking forces applied by the braking mechanism to the guide rail successfully reduce a speed of the elevator car without resulting in failure of the guide rail.

In particular embodiments, the tip section may include a tip cavity disposed therein. Further, the tip section may include a stiffener disposed in the tip cavity to reinforce and provide rigidity to the tip section. Further, the stiffener may be substantially baffle-shaped. Further, the guide rail may be formed from a single piece of sheet metal. Further, the web section may comprise more than two thicknesses of sheet metal. Further, the tip section comprises at least three thicknesses of sheet metal without a gap therebetween. Further, the braking mechanism may apply a frictional force to the tip section of the guide rail when desired to reduce the speed of the elevator car along the hoistway. Further, the brake mechanism may apply a frictional force to the web section of the guide rail when desired to reduce the speed of the elevator car along the hoistway. Further, the guide rail may extend substantially seamlessly along an entire length of the hoistway. Further, the guide rail may be formed in the hoistway from a sheet metal stock. Further, the guide rail may be formed in the hoistway by a process including one or more of rolling, punching and/or welding.

The subject matter, which is regarded as the invention, is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The foregoing and other features, and advantages of the invention are apparent from the following detailed description taken in conjunction with the accompanying drawings. <FIG>,<FIG>,<FIG> are there to understand the invention better and do not form part of the invention. The accompanying drawings are:.

Shown in <FIG> is an elevator system <NUM>. The elevator system <NUM> is located in a hoistway <NUM> and includes one or more guide rails <NUM> affixed to the hoistway <NUM>. The guide rails <NUM> are connected to an elevator car <NUM> to guide the movement of the elevator car <NUM> through the hoistway <NUM>. As shown in <FIG> and <FIG>, the elevator car <NUM> includes at least one guide shoe <NUM> which interfaces with the guide rail <NUM>.

An example, not forming part of the invention, of a guide rail <NUM> is shown in <FIG>. The cross-section is formed from a sheet metal, which may be bent, roll-formed, welded, and/or otherwise manipulated into the final shape. The guide rail <NUM> of <FIG> is formed from a single piece of sheet metal. In other embodiments, however, the guide rail <NUM> may be formed of two or more pieces of sheet metal formed into the guide rail <NUM>. The guide rail <NUM> includes a base <NUM> having two base pads <NUM> configured to rest against the wall of the hoistway <NUM>. A web <NUM> extends in one direction from the base <NUM> into the hoistway <NUM> toward the elevator car <NUM>. To enhance stiffness of the guide rail <NUM>, in a transition area between the base <NUM> and the web <NUM>, there is a space <NUM> between an inner sheet <NUM> and an outer sheet <NUM> of material. Either or both of the base <NUM> and the web <NUM> comprise multiple layers of sheet metal material such that rail <NUM> has sufficient stiffness and rigidity sufficient to guide the elevator car <NUM>. The web <NUM> extends to a tip section <NUM>. The tip section <NUM>, as shown in <FIG>, may have the same dimensional shape as a typical steel guide rail. The tip section <NUM> includes one or more material thicknesses <NUM> to form an exterior portion <NUM> of the tip section and a tip cavity <NUM> inside the tip section <NUM>. As shown in <FIG>, the elevator car <NUM> has a guide shoe <NUM> including a safety brake <NUM>. When a condition exists in which the elevator car <NUM> needs to be stopped, the safety brake <NUM> is actuated to engage guide rail <NUM> and stop the elevator car <NUM>. More specifically, safety brake <NUM> applies braking forces to the exterior <NUM> of tip section <NUM>, in order to stop the elevator car <NUM>. One or more stiffeners <NUM> are located in the tip cavity <NUM> and span at least partially across the tip cavity <NUM> to stiffen the tip section <NUM> and allow it to withstand such braking forces. If the tip section <NUM> is not sufficiently stiff, when braking forces are applied, the tip section <NUM> could structurally fail, requiring replacement of the guide rail <NUM>. In some embodiments, such as in <FIG>, the stiffeners <NUM> may be baffle-shaped. In other embodiments, such as in <FIG>, the stiffeners <NUM> may be ribs extending toward the sides <NUM> of the tip section <NUM>, or as in <FIG>, the stiffeners <NUM> may comprise loops of material disposed in the tip cavity <NUM>. In other embodiments, a filler material may be inserted in the tip cavity <NUM> by injection or other means to add additional stiffness to the tip section. In addition to the exemplary embodiments shown and described herein, many other variations of tip section <NUM>, with various configurations of stiffeners <NUM>, also exist that are consistent with the present invention.

The guide rail <NUM> shown in <FIG> is merely exemplary, and other embodiments of guide rail <NUM> shape are shown in <FIG>. In <FIG>, the guide rail <NUM> includes a triangular-shaped base <NUM> from which the web <NUM> extends to the tip section <NUM>. The web <NUM> of the guide rail <NUM> comprises two material thicknesses <NUM>, as opposed to the four material thicknesses of the embodiment shown in <FIG>. The base includes a corrugated-shaped base pad <NUM> to interface with the wall of the hoistway <NUM>. Referring now to <FIG>, the guide rail includes a flat base <NUM> with a folded base pad <NUM>. The web <NUM> of the guide rail <NUM> of <FIG> also comprises two material thicknesses <NUM>. The embodiment of <FIG> includes a triangular base <NUM>, and a web <NUM> which comprises four material thicknesses. The tip section <NUM> includes stiffeners <NUM> extending into the tip cavity <NUM>. <FIG> shows a guide rail in which the tip section <NUM> does not include a tip cavity <NUM>, and the web <NUM> has two material thicknesses <NUM>. Having the wall-thicknesses <NUM> side by side in the tip section <NUM> increases rigidity due to the lack of gap and will therefore withstand braking forces applied thereto. Shown in <FIG> is a guide rail having a base <NUM> with two base pads <NUM>, one base pad <NUM> at each end of the base <NUM>. The web <NUM> comprises four material thicknesses, and the tip section <NUM> includes two stiffeners <NUM> extending to a tip end <NUM> of the tip section <NUM>.

Another guide rail <NUM> formed from a single piece of sheet metal is shown in <FIG>. The guide rail <NUM> includes a flat base <NUM> having two base pads <NUM> configured to rest against the wall of hoistway <NUM>. The web <NUM> extends in one direction from the base <NUM> toward the elevator car <NUM>. Here, the web <NUM> comprises two web legs <NUM> which define a triangular-shaped web <NUM>. The tip section <NUM> comprises three material thicknesses <NUM> abutting one another with no gaps therebetween, effectively a solid form to withstand braking forces applied thereto.

As shown in <FIG>, a guide rail <NUM> may be utilized with a safety brake <NUM> which engages the web <NUM> of the guide rail <NUM>. The brake frame <NUM> is configured to engage the tip section <NUM> with a guide shoe <NUM>. A braking portion <NUM> extends around the tip section <NUM> to the web <NUM>, inboard of the tip section <NUM>. When desired, the safety brake <NUM> is engaged and applies braking force to the web <NUM> to stop the elevator car <NUM>. Such a safety brake <NUM> configuration requires less reinforcement of the tip section <NUM> than that of a typical safety brake, in which the safety brake <NUM> engages the tip section <NUM>. Further, the unique brake frame <NUM> configuration prevents removal of the brake frame <NUM> (and the elevator car <NUM>) from the guide rail <NUM> in the event of seismic movement of the building, or similar circumstances. It is prevented because the clearance of the brake frame <NUM> to the web <NUM> is smaller than a width of the tip section <NUM>.

Forming the guide rail <NUM> from sheet metal allows for a lighter weight guide rail <NUM> when compared to a typical steel guide rail that has sufficient stiffness and rigidity. A lighter weight guide rail <NUM> makes for easier and safer installation of the guide rail <NUM> in the hoistway <NUM>. Further, as shown in <FIG>, the guide rail <NUM> may be formed onsite, even inside the hoistway <NUM>. Here a forming machine <NUM> including rollers <NUM>, welders (not shown) and other components necessary to form the guide rail <NUM> from a flat piece of sheet metal, is located in the hoistway <NUM>. A sheet metal stock <NUM> is fed into a first end <NUM> of the forming machine <NUM>, and is rolled, formed, punched, and/or welded into a guide rail <NUM> having a desired cross section. The finished guide rail <NUM> exits a second end <NUM> of the forming machine <NUM> and, in some embodiments, may be positioned in the hoistway <NUM> and/or secured thereto by the forming machine <NUM>. Sometimes, the forming machine <NUM> may be configured to travel along the hoistway <NUM> as the guide rail <NUM> is formed. For example, the forming machine <NUM> may form a desired length of guide rail <NUM> which is positioned in the hoistway <NUM> and secured thereto. The forming machine <NUM> then is urged along the length of rail <NUM> via internal or external means, and forms a second length of guide rail <NUM>. This process can be continued until the entire guide rail <NUM> is completed. Utilizing onsite forming of the guide rail <NUM> allows for simplified installation process, and in some cases, a single unitary guide rail <NUM> extending the entire length of the hoistway <NUM> can be formed. Such a guide rail <NUM> having no seams between discrete guide rail <NUM> segments eliminates mismatches that occur between segments and results in smoother and quieter operation of the elevator system <NUM>.

Claim 1:
A guide rail (<NUM>) for an elevator system (<NUM>) in a hoistway (<NUM>), comprising:
a base (<NUM>) connectable with a wall of the hoistway (<NUM>);
a web section (<NUM>) connected to and extending from the base (<NUM>); and
a tip section (<NUM>) disposed at an end of the web section (<NUM>) and operably connectable to an elevator car (<NUM>) of the elevator system (<NUM>);
wherein the base (<NUM>) and the tip section (<NUM>) are formed of one or more thicknesses (<NUM>) of sheet metal material and configured such that braking forces applied to the guide rail (<NUM>) by a braking mechanism (<NUM>) successfully reduce the speed of the elevator car (<NUM>) without resulting in failure of the guide rail (<NUM>), wherein the web section (<NUM>) comprises two thicknesses (<NUM>) of sheet metal material,
characterized in that
the base (<NUM>) is triangular-shaped and includes a corrugated-shaped base pad (<NUM>) to interface with the wall of the hoistway (<NUM>).