The present invention generally relates to an apparatus for assisting a user in climbing a tall structure or tower.
Related climbing assistance devices contain a pulley system, a yoke attachable to a harness of a climber, and a counterweight. The counterweight is used to counterbalance a user's weight when climbing a ladder in a tall structure such as a windmill or a wind turbine. Due to the provision of a counterweight, a user is required to exert less energy during a long climb.
The yokes of related climbing assistance devices are typically attached to the user's shoulders, and the counterweight is attached to the pulley system using a single guide cable. The counterweight and guide cable are positioned either behind the user or to a side of the user, such that the user is positioned substantially between the ladder and the counterweight. In the related systems, the counterweight is required to extend beyond a centerline of the ladder, and at times, to be angled from the ladder or positioned to a side of the ladder. This type of positioning will exert a substantial amount of undesirable lateral loads to the top of the tower or climbing structure and may cause a break in the ladder if tension is applied.
Further, since the counterweight is attached via a single guide cable, the movement of the counterweight, during ascent and descent, will cause the counterweight to create a frequency/counter frequency such that the counterweight will twist. Such occurrence causes unsafe conditions for the user and can result in disruption of the weight distribution of the user. As climbing structures become taller and taller, the risk of counterweight twisting increases since towers are extremely vulnerable to harmonic failure.
In related climbing assistance devices, there is no means to return the yoke to an upper or lower position. Thus, if one person ascends or descends a tower, the yoke must stay in that position until someone physically moves the yoke to another level or platform. The inability to move the yoke, unless physically moved by a user, restricts the use of the related systems to just a single person.
In view of the foregoing, aspects of the present invention are provided to address at least the above problems. Thus, an exemplary feature of the present invention is to provide a climbing assistance device that results in enhanced control of a counterweight to increase safety of a user. In an illustrative, non-limiting embodiment, a climbing assistance device is provided. The climbing assistance device has a connection assembly disposed at a predetermined location on the structure, a yoke attachable to a person, a counterweight connected to the yoke by a cable which passes through a pulley system, and a stabilizer operative to stabilize the counterweight to prevent rotation thereof.
By employing the device of the present invention, a counterweight remains stable during ascent and descent, and the load of the counterweight is controlled. Such features increase the safety of a user.
Aspects of illustrative, non-limiting embodiments of the present invention will become more apparent by describing in detail embodiments thereof with reference to the attached drawings in which:
The following description of illustrative, non-limiting embodiments of the invention discloses specific configurations and components. However, the embodiments are merely examples of the present invention, and thus, the specific features described below are merely used to more easily describe such embodiments and to provide an overall understanding of the present invention. Accordingly, one skilled in the art will readily recognize that the present invention is not limited to the specific embodiments described below. Furthermore, the descriptions of various configurations and components of the present invention that are known to one skilled in the art are omitted for the sake of clarity and brevity.
The yoke assembly 10 can be any type of yoke suitable for climbing, and is shown in
The counterweight 70 is provided on a side of the ladder 60 which opposes the yoke assembly 10. The counterweight 70 is used to counterbalance a user's weight to reduce the amount of energy exerted during climbing of the ladder 60. Service or repair work on tall structures, such as a windmill or a wind turbine, require a user to repeatedly climb up and down a series of ladders. The reduction of user fatigue and increased safety are of great concern. As stated above, the counterweight 70 is provided on an opposite side of the ladder 60 as the yoke assembly 10 (i.e., the counterweight 70 is provided on the backside of the ladder 60). Thus, the yoke assembly 10 will not become entangled with the counterweight 70. Further, there are no other structures provided behind the ladder to interfere with the counterweight 70 and its respective cables, etc. Due to the positioning of the counterweight 70 and the yoke assembly 10, the load between the user and the counterweight 70 is centralized in a more balanced manner and is controlled around the ladder 60.
The stabilizer of
The counterweight 70 is provided with a base weight and can have additional weight adjustments to allow a user to set the counter balance to a preferred setting. The yoke assembly 10 can also be provided with a removable weight to counter the counterweight 70 for users of a less than average weight class.
As set forth above, the counterweight 70 is connected to the yoke assembly 10 via the center cable 40. Therefore, as a user ascends up the ladder 60, the length of the center cable 40 on the user side decreases, while the length of the center cable 40 on the counterweight 70 side increases. Thus, the load on the counterweight 70 side of the ladder 60 in turn increases. As structures or towers reach heights of greater than 55 meters, a user, especially a user of a less than average weight class, must expend great force to begin descent. Accordingly, a weight stabilizer can be provided to ensure that the starting weight for the ascent and descent on the ladder 60 will be approximately the same. The weight stabilizer can include an elastic membrane that is attached to the connection assembly 170 at one end and to the counterweight 70 at an opposite end, such that the elastic membrane follows along the center cable 40 between the connection assembly 170 and the counterweight 70. The elastic membrane elongates and stretches as the counterweight 70 descends down the ladder. Due to the elasticity provided therein, the elastic membrane will help carry a portion of the load provided by the counterweight 70 and the center cable 40, such that the weight becomes stabilized. This in turn will enable a user to easily descend back down the ladder 60 even when the tower or structure is greater than 55 meters in height.
The counterweight 70 can be provided with a dynamic brake system 75 that prevents a runaway condition during descent of the counterweight 70. The brake system 75 is provided inside the counterweight 70, as shown by the dashed lines in
As shown in
A sensor system can also be provided for the purpose of recording and transmitting the movement of the yoke assembly 10. A remote station or facility (not shown), can use this information for various purposes including recording personnel movement for maintenance verification and monitoring for safe movement including emergency indication of a fall.
The information provided by the sensor system can further include a duration of which the yoke assembly 10 is in use. The duration includes the time the yoke assembly 10 leaves a docking position at a top or bottom of the ladder 60 to a time the yoke assembly 10 returns to the docking position at the top or bottom of the ladder 60. A velocity of the user can be monitored, as well as how long the motor of the yoke return assembly 110 is in use (i.e., to move either an empty yoke assembly 10 or a yoke assembly 10 containing equipment). Further, the sensor system may be provided with the ability to control, by authentication, which user is permitted to use the climbing assistance device. Authentication methods may include, but are not limited to, RFID passive or active tags, use of a PIN number, fingerprint identification, retinal scan, voice recognition, etc.
The sensor system can be formed of standard sensors known in the art for recording and transmitting positional information and data. Such sensors can be positioned at intervals along the length of the ladder 60. Further, a microchip or other conventional device for recording and transmitting data is provided, for example, at the base of the tower or structure. The microchip is configured to communicate with the sensors. Data provided by the sensors and/or microchip will be transmitted wirelessly to either a remote portable device or a facility. Conventional communication systems can be used to record and transfer the data (i.e., Bluetooth technology and SCADA systems). Non-limiting examples of sensors include: an altimeter—used to measure altitude, an accelerometer—used to measure acceleration (taking the integral of this value will give velocity, and the integral of velocity will give position), and a rotary counter placed on a sheave or pulley to measure rotations and the sheave or pulley circumference can be used to give distance. Non-limiting examples of microchips can include a PIC Microcontroller, an Atmel AVR, a BASIC Stamp, a Gumstix Waysmall, etc.
Further, a tensioner device 130 is provided. The tensioner device 130 is connected to the ground 120 at one end and connected to the guide cables 90 of the counterweight 70 at the other end. The tensioner device 130 provides tension balance to the system, and ensures adequate spacing of the guide cables 90. Such provisions reduce fatigue on the guide cables 90.
In an alternate embodiment, the counterweight passage 150 is equipped with lighting for use in emergency situations, such as a power outage. When illuminated, the lights of the counterweight passage 150 will act as emergency lights to guide a user safely up or down the ladder 60 or to a nearest platform. Any type of conventional emergency illuminating device can be used so long as the device does not obstruct the ability of the counterweight 70 to pass through the counterweight passage 150.
Additional devices, similar to the counterweight parking device 180, can be provided at various locations along the ladder 60 to act as guide devices, and to maintain control of the guide cables 90 and the counterweight 70. Such guide devices are similar to the counterweight parking device 180, except that a thickness of the rubber portion along the inner periphery of the center opening is reduced so as not to hinder movement of the counterweight 70 therethrough. Since the guide devices are similar in appearance to the counterweight parking device 180, the guide devices are not reproduced in the figures.
In the non-limiting embodiments described above, certain features such as the counterweight 70, the counterweight parking device 180 and the counterweight passage 150, can be formed of molded reinforced plastic and composite materials that are commonly known in the art, and the counterweight 70 can be molded so as to be hollow. By forming such parts with reinforced molded plastic and composite material parts, rather than with metal, the cost of manufacturing, inventory, assembly, shipping & handling, installation and service can be reduced.
The previous description of the non-limiting embodiments is provided to enable one skilled in the art to make and use the present invention. Moreover, various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles and specific examples defined herein may be applied to other embodiments without the use of inventive faculty. For example, although the climbing assistance aid is discussed in regard to a windmill or wind turbine, the features of the present invention can be applied to any type of structure that requires a user to ascend or descent great heights, such as cell towers, radio towers, elevator shafts, vertical mine shafts, tower cranes and ski lifts. Therefore, the present invention is not intended to be limited to the embodiments described herein, but is to be accorded the widest possible scope as defined by the recitations of the claims and equivalents thereof.
Filing Document | Filing Date | Country | Kind | 371c Date |
---|---|---|---|---|
PCT/US06/12589 | 4/4/2006 | WO | 00 | 10/2/2008 |