Rope guidance for second device used on DuraHoist arm

A line guidance device (40) is provided for use with a confined space entry/retrieval hoist and fall protection anchorage system (10) and includes a line guide (46) that guides a line from an extend/retract line device (22) past another extend/retract line device (20) with both devices (20, 22) mounted on a backside (24) of a mast (12) of the system (10).

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority of European Appln. No. 16157759.8, filed on Feb. 28, 2016 entitled “Rope Guidance for Second Device Used on Durahoist Arm”, which is hereby incorporated by reference in its entirety.

FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not Applicable.

Not Applicable.

FIELD

This disclosure relates to worker entry/retrieval systems for manhole and other confined space applications and to fall protection for such systems, and in more particular applications, to lightweight and portable versions of such systems.

BACKGROUND

Confined space entry/retrieval hoist and fall protection anchorage systems are known for lowering and raising a worker into and out of a confined space, such as a manhole, and for providing fall protection during the entry/retrieval and, at least in some applications, while the worker performs tasks in the confined space. Such systems typically have a mast/boom structure with two separate devices attached to the mast/boom structure for extending and retracting support lines that are attached to a worker suspended from the system, with one of the devices being a winch having a winch line supported by the mast/boom structure and connected to the worker for lowering and raising the worker into and out of the confined space, and the other device being a self-retracting lifeline (SRL) having another line supported by the mast/boom structure and attached to the worker for providing fall protection during the entry/retrieval of the worker and, at least in some instances, while the worker performs tasks in the confined space. Conventional systems mount the winch on the side of the mast/boom structure that faces away from the confined space/manhole and mount the SRL on the side of the mast/boom that faces the confined space/manhole. While conventional systems have proven suitable for their intended use, the location of the SRL on the side of the mast/boom structure facing the confined space/manhole increases the resultant load applied to the system, complicates the operation of the SRL, and increases the safety hazard because the SRL is typically mounted directly above the confined space/manhole due to the positioning of the mast/boom closely adjacent the confined space/manhole. Accordingly, there is room for improvement in a system that would address one or more of these issues.

SUMMARY

In accordance with one feature of this disclosure, a confined space hoist and fall protection anchorage system is provided for raising and lowering a worker into and out of a confined space. The system includes a longitudinally extending mast, a masthead, first and second extend/retract line devices carried on the mast and positioned on a first side of the mast. The first extend/retract line device has a first line extending from the first extend/retract line device to the masthead to connect to a worker suspended by the system. The second extend/retract line device has a second line extending from the second extend/retract line device to the masthead to connect to the worker suspended by the system. The first extend/retract line device is mounted on the mast between the second extend/retract line device and the masthead. The system further includes a line guidance device including a mast mount structure connected to the mast, and an extend/retract line device mount structure positioning the first extend/retract line device on the first side of the mast. A line guide is located on the line guidance device between the mount structures to guide the second line between the mast and the first extend/retract line device as the second line travels from and to the second extend/retract line device and the masthead as a worker suspended from the second line is lowered and raised by the system.

As one feature, the system includes a mast arm mounted on the mast adjacent an end of the mast and extending from a second side of the mast to the masthead. The second side is an opposite side of the mast from the first side.

In one feature, the line guide is a pulley mounted in the line guidance device for rotation.

According to one feature, the mast mount structure includes a pair of spaced flanges located on opposite sides of the mast and secured to the mast with a plurality of fasteners and the extend/retract line device mount structure is a plate configured to secure the first extend/retract line device with a plurality of fasteners.

As one feature, the masthead includes a pair of masthead pulleys, one of the masthead pulleys configured to guide the first line for movement as the first line travels to and from the first extend/retract line device and the other masthead pulley being configured to guide the second line for movement as the second line travels to and from the second extend/retract line device. In a further feature, one of the masthead pulleys is mounted in the masthead at a first location, the other of the masthead pulleys mounted in the masthead at a second location, with the second location being spaced further from the mast than the first location.

According to one feature, the mast extends in a vertical direction.

As one feature, the first extend/retract line device is a winch and the first line is a winch cable.

In one feature, the second extend/retract line device is a self-retracting lifeline device and the second line is a lifeline.

According to one feature, a confined space hoist and fall protection anchorage system is provided for raising and lowering a worker into and out of a confined space. The system includes a longitudinally extending mast, a masthead, first and second device mount locations on the mast and configured to mount respective first and second extend/retract line devices to the mast so that the first and second extend/retract line devices are positioned on a first side of the mast, with the first line extend/retract line device having a first line extending from the first extend/retract line device to the masthead to connect to a worker suspended by the system, and the second extend/retract line device having a second line extending from the second extend/retract line device to the masthead to connect to the worker suspended by the system. The first extend/retract line device mount location is located on the mast between the masthead and the second extend/retract line device mount location. The system further includes a line guidance device having a mast mount structure connected to the mast at the first device mount location, a device mount structure configured to position the first extend/retract line device on the first side of the mast, and a line guide located on the line guidance device between the mount structures, the line guide configured to guide the second line between the mast and the first extend/retract device as the second line travels from and to the second extend/retract line device and the masthead as a worker suspended from the second line is lowered and raised by the system with the first extend/retract device mounted on the device mount structure and the second extend/retract line device mounted at the second device mount location.

In one feature, the line guide is a pulley mounted in the line guidance device for rotation.

According to one feature, the first extend/retract line device is mounted to the device mount structure, and the second extend/retract line device is mounted at the second device mount location and positioned on the first side of the mast.

As one feature, a line guidance device for use with a confined space hoist and fall protection anchorage system is provided for raising and lowering a worker into and out of a confined space. The system includes a longitudinally extending mast, a masthead, first and second extend/retract line devices positioned on a first side of the mast, and a mast arm mounted on the mast adjacent an end of the mast and extending from a second side of the mast to the masthead. The second side is an opposite side of the mast from the first side. The first extend/retract line device has a first line extending from the first extend/retract line device to the masthead to connect to a worker suspended by the system. The second extend/retract line device has a second line extending from the second extend/retract line device to the masthead to connect to the worker suspended by the system. The first extend/retract line device is mounted on the mast between the second extend/retract line device and the masthead. The line guidance device includes a mast mount structure connectable to the mast, an extend/retract line device mount structure configured to position the first extend/retract line device on the first side of the mast, and a line guide located on the device between the mount structures to guide the second line between the mast and the first extend/retract line device as the second line travels from and to the second extend/retract line device and the masthead as a worker suspended from the second line is lowered and raised by the system.

In one feature, the line guide is a pulley mounted in the line guidance device for rotation.

According to one feature, the mast mount structure is a pair of spaced flanges located to be positioned on opposite sides of the mast and secured to the mast with a plurality of fasteners, and the extend/retract line device mount structure is a plate configured to secure the first extend/retract line device with a plurality of fasteners.

Other features and advantages will become apparent from a review of the entire specification, including the appended claims and drawings.

DETAILED DESCRIPTION

With reference toFIGS. 1 and 2, a confined space, entry and retrieval hoist and fall protection anchorage system10is shown for lowering and raising a worker into and out of a confined space, such as a manhole shown at11, and for providing fall protection to the worker during entry and retrieval and while the worker performs tasks in the confined space. The illustrated system10includes a longitudinally extending mast12extending along a vertical axis13, a masthead14, a mast arm16mounted on the mast12adjacent an end15of the mast12and extending from a front side18of the mast12to the masthead14so as to extend over the confined space/manhole11, preferably centering the masthead14over the confined space/manhole. The length of the mast12and the length of the mast arm16can be adjusted, as can be the extension angle of the mast arm14relative to the mast12. The general construction and assembly of the components12,14, and16are known, with commercially available examples being marketed as a family of products under the trademark “Miller DuraHoist Confined Space System” by Honeywell International Inc. Other suitable constructions for the components12,14and16are commercially available and can be utilized according to this disclosure. Accordingly, the details of these components are not necessary for an understanding of the inventive concepts disclosed herein; however, some details will be discussed as they relate to the inventive concepts disclosed.

The system10further includes first and second extend/retract line devices20and22carried on the mast and positioned on a backside24of the mast12. The first extend/retract line device20is shown in the form of a hand operated winch20having a line26extending from the winch20to the masthead14and then downward from the masthead14to connect to a worker suspended by the system10. The second extend/retract line device22is shown in the form of an SRL22having a lifeline28extending from the SRL22to the masthead14and then downward from the masthead14to connect to the worker suspended by the system10. In the illustrated embodiment, the winch20is mounted to a first mount location30on the mast12, and the SRL22is mounted to a second mount location32on the mast12, with the second mount location32being spaced further from the masthead14than the first mount location30, which thereby positions the winch20on the mast12between the SRL22and the masthead14. In the illustrated embodiment of the mast12, each of the mount locations30and32are defined by a pair of fastener receiving openings34formed in the mast12, with a series of equally spaced openings34being provided so as to allow the locations30and32to be altered according to the particular requirements of the confined space/manhole application for which the system10is being used. The SRL22can either be attached directly to the mast12with suitable fasteners, or via a suitable mount bracket that would carry the SRL22and be mounted to the mast12with suitable fasteners, with the details of such a mount bracket being dependent upon the particular configuration of the SRL22being utilized with the system10. It should be understood that there are many known, commercially available winches and SRL's that are suitable for use with the system10, and accordingly, the details of the winch20and the SRL22are not critical to an understanding of the inventive concepts disclosed herein.

The system10further includes a line guidance device40that directs the line28of the SRL22past the winch20as it travels between the SRL22and the masthead14. As best seen inFIG. 2, the line guidance device40is positioned on the backside24of the mast12and includes a mast mount structure42connected to the mast12, an extend/retract line device mount structure44(best seen inFIGS. 3-5) mounting the winch20and positioning the winch20on the backside24of the mast12, and a line guide46(again best seen inFIGS. 3-5) located on the line guidance device40between the mount structures42and44to guide the line28between the backside24of the mast12and the winch20as the line28travels from and to the SRL22and the masthead14as a worker suspended from the line28is lowered and raised by the system10.

In the illustrated embodiment, the mast mount structure42is provided in the form of a pair of spaced flanges48located on opposite sides of the mast12and secured to the mast12with a pair of suitable fasteners50, such as, for example, quick release pins50or threaded fasteners50. As best seen inFIG. 3, the extend/retract line device mount structure44in the illustrated embodiment is provided in the form of a plate52configured to secure the winch20with a plurality of suitable fasteners54, such as a plurality of threaded fasteners54. The line guide46is provided in the form of a pulley46mounted in the illustrated embodiment in the line guidance device40for rotation about an axis56that extends perpendicular to the vertical axis13of the mast12, with a journal axle58(best seen inFIG. 3) surrounding a suitable threaded fastener60that extends between a pair of structural support flanges62of the device40. The pulley46is positioned between the plate52and a structural support plate64fixed to the flanges48and62to provide structural support to the flanges48and62. In illustrated embodiment, a single piece of metal or other suitable material defines the flanges48and62on each side of the device40. It should be understood that the illustrated construction of the device40provides a simple, low part count, assembly, but that other configurations may be desirable depending upon the requirements of each particular application and the construction of the particular extend/retract line device being mounted by the device40and the specific type of line being guided by the line guide46. For example, the extend/retract line device mount structure44can be provided in other forms then the plate52, depending upon the construction of the particular winch20or other particular type of extent/retract device line device20utilized for a particular application. As another example, other types of structural supports could be utilized to replace the support plate64. As yet a further example, depending upon the specifics of the mast12utilized in the system10for a particular application, something other than a pair of spaced flanges48connected with suitable fasteners may be desirable.

In the illustrated embodiment, the masthead14includes a pair of pulleys70and72, with the pulley70guiding the line26and the pulley72guiding the line28. In this regard, the pulley72is positioned further from the mast12than the pulley70so as to provide horizontal separation between the lines26and28which allows for easier and better attachment of the lines26and28to a worker suspended from the system10and reduces the possibility of the lines26and28becoming tangled. It should be appreciated that depending upon the requirements of any particular application the pulley70could be utilized to guide the line28and the pulley72could be utilized to guide the line26. Also in the illustrated embodiment, the mast arm16is mounted to the mast12by pair of brackets74located on opposite sides of the mast12and further supporting a pair of pulleys76that guide the lines26and28from the devices20and22to the pulleys70and72, with each of the pulleys76guiding a respective one of the lines26and28. The illustrated embodiment also includes a link or spar78having an adjustable longitudinal length extending from the mast arm16to the brackets74to adjust the angular position of the mast arm16relative to the mast12. Additionally, though not shown, the system10can further include a base configured to structurally support the mast12and the remainder of the system10on a surface surrounding the confined space/manhole11, many suitable types of which are known.

It should be understood that as used herein, the term “line” is intended as a broad term that can include any type of cable, rope, webbing, and/or other line utilized in a winch and/or SRL. It should also be understood that as used herein, the term “mast” is intended as a broad term that includes any type of boom, beam, mast, or other main structural support for a confined space entry/retrieval hoist and fall protection anchorage system.

It should be understood that while a specific embodiment of the system has been shown herein, the disclosure contemplates other possible embodiments, several examples of which have already been provided. As a further example, while the illustrated embodiment shows the winch20being mounted by the line guidance device40at the first location30and the SRL22to be mounted at the second location32, in some embodiments it may be desirable for the SRL22to be mounted by the line guidance device40at the first location30, with the winch20being mounted at the second location32.

It will be appreciated by those skilled in the art that the line guidance device40allows for mounting both the winch20and the SRL22on the backside24of the mast12and that, in comparison to conventional systems that mount the winch20and SRL22on opposite sides of the mast12, the positioning of the winch20and the SRL22on the backside24decreases the resultant load applied to the system10, increases the bearing capacity of the system10, increases comfort and ease of use during operation of the system10, minimizes the interference of the SRL with a worker being lowered and/or raised by the system10, and reduces the safety hazard because the SRL22is not mounted above the confined space/manhole.