KR100730271B1 - Absolute position reference system - Google Patents

Abstract

The present invention relates to a position reference system for use with a carrier such as an elevator (12). Such a system includes a suspension device, or a cord attached or embedded to a first moving coupling, such as a rope or coated steel belt. The reader 28 at the fixed position determines the position of the carrier.

Position Reference System, Code, Reader, Elevator Car, Elevator System, Primary Motion Coupling

Description

Absolute Position Reference System {ABSOLUTE POSITION REFERENCE SYSTEM}

The present invention relates generally to elevators, and more particularly to an apparatus for determining the position of an elevator car.

Absolute position reference systems are known in the art. U. S. Patent 5,023, 434 relates in particular to a position indicating device for an overhead conveying system. The position indicating device includes a long code carrier which carries multi-numeric code marks along its length. A code reading device fixed on a transport carrier such as a trolley, crane or other moving mechanism reads the code on the code carrier. The code marks are arranged on the code carrier side by side in a single row or track, in order to prevent erroneous readings and ensure the accuracy of the reading position of the code carrier when the carrier carrier and hence the code reading device are tilted relative to the code carrier. The " m " of the mark is formed to provide one code word, which is placed next to each other and only visible once or unique along the entire code carrier. The code reader has a read station with three sets of read heads per station distributed equidistantly at least a distance corresponding to the number of number of code words to provide an unambiguous position indication in the processing of output from all three read heads. Has for each bit.

U. S. Patent No. 5,138, 560 to Lanfer et al. Shows a position indicating device comprising a code carrier having a multi-numerical code mark in one track along its length. The code mark is combined into the block with which the block identifier is related. There is a code reader and an auxiliary reader, respectively, in cooperation with the code carrier and block identifier. Along the path of travel, the code carrier and code reader are placed opposite one another. The block identifier is associated with a block in order to enable an increase in the length of the addressable travel path without losing position accuracy or increasing the number of code marks within one code word. From the block identifier, the auxiliary reader can recognize whether the code reader is reading only code marks from one block. In this way, the travel path can be divided into non-critical zones, which are gaps between the critical zones where the exact location of the vehicle must be known and therefore the blocks must be allocated and simply connect the important zones to each other.

US Pat. No. 5,821,477 to Gerstenkorn shows a reflector mounted in an elevator shaft and having a code symbol in two tracks in the area of the stop layer. The detector on the car can read the code symbol to connect the door contacts when the car is within the arrival area and the reset area of the stop layer. The symbol is evaluated by a two-channel evaluation circuit having an optical transmitter that detects and illuminates the track and a charge-coupled element sensor that detects the reflected image. The pattern recognition logic system and computer for each channel recognizes the pattern in the image to generate car position and speed information and to activate the relay connecting the door contacts.

U. S. Patent No. 6,435, 315 to Zaharia describes the position of an elevator car in a hoist including a code rail containing an optically readable indicia mounted in a hoistway adjacent to the car's path of travel. To determine the device. At least one camera is mounted on the vehicle for movement with it to scan code rail signs and provide data indicative of the position of the vehicle relative to the vehicle controller.

PCT Publication No. WO 01/83352 to Wegener et al. Relates to a device for determining the position of an elevator car during evacuation comprising a circulation cable connected to the elevator car and provided with a mark. A unit for detecting a mark is provided.

These position reference systems work well, but there is still a need for better systems without additional equipment along the travel paths such as elevator hoist walls.

It is an object of the present invention to provide a system for determining the position of a vehicle without further provision along the path of travel.

The above object is achieved by the position reference system of the present invention.

According to the present invention, a position reference system for providing information on the position of a carrier such as an elevator is provided. The position reference system includes a primary kinematic coupling, such as a cord attached or embedded to the suspension device, or a rope or coated steel belt. The position reference system further includes a reader in a fixed position that reads the code to determine the position of the vehicle.

A method of measuring the amount of tension in a primary kinematic coupling to an elevator car is provided. This method includes providing a cord to the primary kinematic coupling, measuring the actual length for each sign that forms the cord, and changing the actual length resulting from the amount of tension in the primary kinematic coupling. And detecting the amount of tension from the detected change in the actual length.

Also provided is a method of determining the slip amount of an elevator car. This method comprises the steps of generating a drive command to the primary motion actuator, the drive command using the position reference system comprising a code on the primary motion coupling attached to the elevator car and a reader for reading the code and then the position of the elevator car. And measuring the change of the position according to the position reference system to the change of the position according to the driving command.

Other details of the absolute positioning reference system of the present invention are set forth in the following detailed description and the accompanying drawings in which like reference numerals refer to like elements, along with other objects and advantages thereof.

1 is a schematic diagram of an elevator system including a position reference system of the present invention.

2 is a schematic representation of a primary motion coupling used in the position reference system of the present invention.

Referring now to FIG. 1, elevator system 10 includes an elevator car 12 that moves vertically within hoistway 14 in a building structure. The primary motion coupling 16 extends from the end point 18 through the idler sheave 20 attached to the car 12 over the drive sheave 22 to the counterweight 24. The drive sheave 22 can be driven using any suitable means known in the art to move the elevator car 12 vertically in a hoistway between a series of floors (not shown). The primary motion coupling 16 is used to suspend the car 12 and may be a rope, a plurality of ropes or a coated steel belt (CSB) as shown in FIG. 2. In addition, as shown in FIG. 2, the primary motion coupling 16 may include a plurality of cables 40 and / or coatings 42.

According to the invention, the position reference system of the invention comprises a cord 26 as shown in FIG. 2 attached or embedded with respect to the primary motion coupling 16. The elevator positioning system further includes a reader 28 in the fixed position. The reader 28 is used to read the code 26 to calculate the absolute position, velocity, acceleration and jerk of the car 12. Reader 28 may include any suitable reader known in the art. The type of reader 28 to be used will be a function of the nature of the code 26.

In addition, the cord 26 and reader 28 may be used to directly measure the amount of tension or slip of the primary kinematic coupling 16 of the elevator car 12. The amount of tension can be measured by direct measurement of the cord. The cord will be of known length when applied to a new primary kinematic coupling. If the primary kinetic coupling is tensioned due to load or wear, the code mark will likewise be tensioned. High resolution signal processing algorithms, as is well known in the art, can be applied to directly measure the amount of tension by measuring the actual length of the code mark. The slip amount can be measured by comparing the measured position with respect to the drive command. The controller of the vehicle uses the feedback from the position reference system to generate a drive command to the primary motion actuator to influence the position control of the vehicle. Ideally, the drive command corresponds exactly to the change in position. However, if the position reference system is independent of slip, any slippage between the drive actuator and the primary kinetic coupling results in a mismatch between a change in position according to the position reference system and a change in position according to the drive command. This mismatch is a direct measure of slip and slip corresponds to the amount of wear on the primary motion actuator and primary motion coupling.

In a preferred embodiment of the invention, the reader 28 is located along the primary motion coupling 16 in a fixed position between the drive sheave 22 and the end point 18. In this way, the drive sheave slip amount is not important for the position measurement. Thus, from the difference between the absolute position measurement and the drive command, the slip amount and the corresponding wear amount can be calculated. Such calculation may be through a lookup table, its equivalent function representation, or any of a variety of means well known in the art.

The compensation for the amount of tension of the primary kinematic coupling 16 can be measured directly from the cord 26 or can be estimated by the empirical function of load and temperature based on the primary kinematic coupling test. Depending on the accuracy of this estimation, a separate seal sensor (not shown) may be required. The information may then be used in the estimation algorithm to improve position accuracy.

Cord 26 may be embedded in primary motion coupling 16, such as a steel belt, coated in a variety of different ways. For example, the cord 26 may be a physical, optical or magnetic mark or material on the surface of the primary motion coupling 16. It may be advantageous to have a mark along the edge of the primary motion coupling 16 because the edge is not in contact with either the drive sheave 22 or the idler sheave 20 to minimize the amount of wear. Physical marks such as grooves are not good on the surface of the primary motion coupling 16 due to possible induced noise. However, grooves of a given position, distribution, shape, etc. can be designed to an acceptable noise level, such as less than 48 dB, thus allowing its use as a code for a position reference system.

Cord 26 may be a physical, optical or magnetic mark or material embedded within coating 42 of a primary motion coupling, such as the coated belt shown in FIG. 2. This means that the primary kinematic coupling 16 needs to be slightly wide with no cable preferably not centered below the cross section of the coating. The embedded cord 26 may be a hole cut through the primary motion coupling 16. Instead, the primary motion coupling 16, such as the belt shown in FIG. 2, can be assembled in a stacked manner with one layer containing the cord 26.

Cord 26 may also be an additional cable or cord in primary motion coupling 16, such as a belt, such as the belt shown in FIG. 2 having a material property that can be sensed through a coating such as belt coating 42. have.

In addition, the cord 26 may have one or more in the primary motion coupling 16, such as the cable 40 in the belt shown in FIG. 2, having a material property that can be sensed through a coating such as a belt coating 42. The cable 40 can be changed or improved.

The best embodiment of cord 26 includes a magnetic material embedded in a coating on the primary motion coupling, such as belt coating 42. If these materials are materials sensitive to the applied magnetic field, such as iron oxide, the entire primary motion coupling 16, such as coated steel belts, becomes a magnetic tape. In such a case, reader 26 may record, rewrite, or encode information about the belt.

While the preferred embodiment uses encoding on the suspension means between the moving cap and the fixed drive system, the present invention would equally work well for a drive system attached to the moving car 12 with the suspension means attached to the fixed position. will be.

Using the location reference system of the present invention will save installation costs over any approach that requires a separate hoist facility. Additional cost savings come from a reduced list of alternative installations that are not needed. All encoded primary kinematic couplings are preferably the same so as not to increase the number of parts.

Although the present invention has been described in connection with elevator systems, the position reference system of the present invention may be used for other vehicles.

It is evident that an apparatus and method for an absolute position reference system that fully meets the aforementioned objects, means and advantages are provided in accordance with the present invention. Although the present invention has been described in connection with specific embodiments thereof, other alternatives, modifications and variations are apparent to those skilled in the art upon reading the foregoing description. Accordingly, it is to be construed to include these alternatives, modifications and variations as fall within the broad scope of the appended claims.

Claims (12)

Position reference system used in elevator systems to determine the position of the elevator car relative to a fixed reference position, A cord on the primary kinematic coupling of the elevator car, And a reader for reading the code. The position reference system of claim 1, wherein the reader is mounted in a hoistway at a position between an end point of the primary kinematic coupling and a drive sheave. The position reference system of claim 1, wherein the primary kinematic coupling comprises a coated steel belt, and wherein the cord comprises at least one of physical, optical, and magnetic indications on a surface of the belt. The position reference system of claim 1, wherein the primary kinematic coupling comprises a coated steel belt and the cord includes at least one of a physical, optical, and magnetic indication embedded in a coating of the belt. The position reference system of claim 1, wherein the primary kinematic coupling comprises a belt and the cord comprises a hole cut through the belt. The position reference system of claim 1 wherein the primary kinematic coupling comprises a stacked belt with the cord embedded in one layer. The positioning reference system of claim 1 wherein the primary kinematic coupling comprises a belt and the cord comprises at least one of a cable and a cord in the belt having a material property that can be sensed through a coating on the belt. The position reference system of claim 1, wherein the primary kinematic coupling comprises a coated belt and the cord includes a magnetic material embedded in the belt coating. The position reference system of claim 1, wherein the cord is attached or embedded relative to the primary kinematic coupling. Position reference system for use with a carrier with suspension means, A cord on said suspension means, And a reader in a fixed position for reading the code to determine the position of the vehicle. A method of measuring the amount of tension in the primary kinematic coupling to an elevator car, Providing the primary kinematic coupling having a cord; Measuring an actual length for each mark forming the code; Detecting a change in the actual length resulting from the amount of tension in the primary kinematic coupling, Determining the amount of tension from the detected change in actual length. To determine the slip amount of the elevator car, Generating a drive command to the primary motion actuator; Measuring the position of the elevator car after the drive command using the position reference system includes a code and a reader on the primary motion coupling; Comparing a change in position with a position reference system to a change in position with the drive command.

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