Emergency descent control devices are known. U.S. Pat. No. 6,131,697 teaches a rappelling rope controller which utilizes a U-shaped rod supporting three bars of circular cross section movable along the arms of the rod, and enlarged abutments on the free ends of the rod preventing removal of the bars, but no mechanism for releasing the load are present. US Patent Application No. 2010/0236863 teaches an auto-lock compact rope descent device is a bar with holes for guiding a rope used is descent, and a lever designed to pivot or move relative to the bar and compresses the opening of one of the holes. Compressing the opening increases friction and slows or stops descent.
US Patent Application No. 2012/0261212 teaches an anti-panic descender with possibility of ascent that uses a lever. US Patent Application No. 2011/0048852 teaches a descender with fall arrest and controlled rate of descent. US Patent Application No. 2009/0120720 teaches a frictionless descender for abseiling along a rope that also has a handle to control descent. These devices do not show the internal rigging of the rope, and therefore, are not as easy to inspect. Most of these devices provide two loops in a threaded rope, and use a breaking action provided by the lever to slow the movement.
The present invention involves a safety lowering device (SLD) that is a descent control device designed specifically to increase the safety and speed of technical rope rescue operations. This device overcomes a number of potential safety concerns with respect to other descent control devices currently available. A primary advantage of the present invention is its ability to automatically lock off the rope thereby stopping unattended descent. This means that if the user, while using the SLD, becomes incapacitated, the device will automatically stop the progress of the lowering operation avoiding potential injury to patients and attendants. Although this is a relatively uncommon occurrence within the technical rescue community, devices passing this so-called whistle test have gained enthusiastic acceptance for their increased levels of safety.
A further aspect to this invention is its potential for multifunctional use. Besides its use for the lowering of rescue loads up to about six hundred pounds (600 lbs.), the SLD can easily and almost instantly be converted to function as a simple-to-operate rescue belay device. In the event that the belay function becomes locked-up during use, this device can quickly be converted to the lowering function after remedying the issue that caused the lock-up. This aspect will allow users of two rope systems, for belay and lower, to use one device for both functions simplifying training and reducing the risk of skill retention issues when using different devices.
In a primary embodiment of this invention, the rope may be pre-rigged by receiving the rescue rope through the device. In this configuration, the rope cannot become detached from the device unless the rope is physically pulled through the device during its use. To eliminate this possibility, stopper knots are tied on the ends of the rope. This is done prior to the rescue event and is known as pre-rigging, a practice that eliminates potential errors in the heat of a rescue as well as accelerating the rigging process during the rescue event.
Another important aspect of this invention is that all components are completely visible without any disassembly which in turns allows a complete inspection to determine if the device has undergone any wear or damage that might compromise its safety.
A further advantage of the present safety device is its ability to compensate for shock loads potentially encountered in rescue scenarios. Almost all other descent control devices when locked off do not have the ability to allow limited slippage of the rope through the loaded device. If a device that does not allow limited slippage under load is suddenly shock loaded the majority of this potentially large force must be dissipated in the rest of the system with the potential of over-stressing a component and leading to a possible catastrophic failure.
In scenarios where more than one individual will require lowering, it is important to be able to resent the system quickly and safely. High rise rescues during fire events have multiple rescuers using single lines.
These and other aspects of the present invention will become readily apparent upon further review of the following drawings and specification.
The novel features of the described embodiments are specifically set forth in the appended claims; however, embodiments relating to the structure and process of making the present invention, may best be understood with reference to the following description and accompanying drawings. The drawings, which are not drawn to scale, are for illustration of design principles and parts.
Similar reference characters denote corresponding features consistently throughout the attached drawings.
To use the safety device 12 as an effective rescue belay device the unloader components can be detached by removing the shoulder retainer 24, e.g., screw, and swinging a bar clip 28 off of the third bar 20. Although the present invention is described using a U frame 14, the frame 14 of the present invention may instead be made of components having two parallel arms and a closed end 32 which may be attached to an anchor, have a rope R threaded through it, or the like.
To allow rope to be played out of the device 12, it should be apparent that the bars 16, 18, and 20 will need to be separated when the device is loaded. This is accomplished by means of the unloader components of the safety device 12 which in turn supplies a mechanical advantage to separate the bars when the lowering lever 30 is moved towards abutments 22. Depending on the amount of movement of the lever 30, friction is reduced, and the rope R under load is let out with full control. Releasing the lowering lever 30, automatically allows the bars 16, 18, and 20 to move back together thus trapping the rope R between them and stopping the descent.
Further embodiments of the present design are depicted in
This embodiment will allow the device 12 to be installed in the middle of a rescue rope R without needing to thread the rope from its end through the device. The anchor point 32 for the unloader components would be attached to one of these frame 14 elements to allow them to rotate independently from one another allowing midline attachment. It should also be noted that the middle bar 18 will not only be easily slidable but also be able to swing away from the frame to allow midline attachment. Further regarding
In the embodiment depicted in
The simplest handle 30 (or handle base) has a second end 42 that may additionally have a grip 48 (not shown in
Further regarding the telescoping handle 30 of
Also as shown in greater detail in the partial perspective view of
Should the user alternatively want a dual function, this shoulder retainer may be replaced by a ball lock pin 52 to allow for fast conversions from belay to lower and back again, if required. The ball lock pin 52 shown is attached via a cord 54. The ball lock pin 52 is provided at the axle or opening 50 which attaches the handle 30 to the frame 14 in a manner such that the attachment may rotate about the axle at 58 (when the pin 52 is in the opening 50). The brace 34 extends from the axle at 58 to the handle 30 where another opening with pin or axle at 56 is provided. The handle 30 in this embodiment is rotatably attached to the bar clip 28 at that axle 60 disposed on one side thereof as shown.
A pre-rigged prototype safety lowering device and system is an ultra safe lowering device for use in rope rescue. Constructed of high strength metals, primarily stainless steel, it is designed for years of trouble free operation in urban fire and rescue environments. Initially conceived for single rope rescue from the roofs of tall buildings, the safety lowering device can be used to lower up to six hundred pounds in an easy and secure fashion on 12 to 15 millimeter static kern-mantle and laid rescue rope as well as heat resisting aramid fiber ropes. In the pre-rigged prototype the middle bar 18 cannot be rotated out and therefore the device must be pre-rigged from the end of the rope R preventing any possibility of the device 12 coming separated from the rope R during use, in bags, or in shipment.
In use, the device 12 should always be inspected for proper rigging and damage before and after use. It is important hat the user be properly trained in the use of this device 12. When constructing the anchor, proper care should be taken to avoid any obstructions near the device 12 that might interfere with its proper functioning. When loaded the lever 30 will automatically pivot from a parallel orientation (release position) to the frame to a near right angle orientation (belay position) in the embodiments depicted in
At any point while the system is loaded, if the operator lets go of the lever 30, rope movement through the device will be safely and automatically arrested. After the completion of the lower, the unloaded rope can easily be pulled back through the device by holding the lever parallel to the frame, spreading the break bars 16, 18, 20, while a second rescuer pulls the rope through the device from the slack end of the rope. this resents the system for the next lower, if the loaded system is to be unattended take a half hitch on a bight from the slack side and clip it to the load side effectively applying a hark lock to the system. Should the unloading parts need to be removed, a ⅛ inch hex wrench and ⅜ inch open end wrench are required to remove stainless steel shoulder bolt. The handle grip 48 may be a conventional grip, or a ball grip 48. The grip 48 may be replaced by an eye bolt (not shown) for remote actuation via a chord.
It is to be understood that the present invention is not limited to the embodiments described above, but encompasses any and all embodiments within the scope of the following claims.
This application claims the benefit of U.S. Provisional Application Ser. No. 61/631,249 entitled “SLD (Safety Lowering Device)” filed on 30 Dec. 2011, the contents of which are incorporated herein by reference in its entirety.
Number | Name | Date | Kind |
---|---|---|---|
55053 | Brown | May 1866 | A |
288411 | Connolly | Nov 1883 | A |
666879 | White | Jan 1901 | A |
1087440 | Freed | Feb 1914 | A |
4311218 | Steffen | Jan 1982 | A |
5295559 | Nutkins | Mar 1994 | A |
6131697 | Bassett | Oct 2000 | A |
20090120720 | Arms | May 2009 | A1 |
20100236863 | Schwarzenbach et al. | Sep 2010 | A1 |
20110048852 | Wolf et al. | Mar 2011 | A1 |
20120261212 | Bonaiti | Oct 2012 | A1 |
Number | Date | Country | |
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61631249 | Dec 2011 | US |