The present invention is generally directed to a tourniquet for stopping blood loss from an injured limb and is more particularly directed to a tourniquet for use in emergency situations in which a user is able to apply the tourniquet to his or her own arm or leg and occlude blood flow with the use of a single hand.
Loss of blood in emergency situations and particularly in military confrontations is a major cause of death. In these situations, the injured person often does not have access to immediate medical assistance. It is also well known that the use of a tourniquet to stop blood loss provides temporary first aid treatment until medical assistance is available.
It should be quite apparent that in these situations time is of the essence and thus one handed simple and expedient operation of such an infield circulatory constriction device must be efficiently effected.
Many attempts have been made to develop tourniquets for such in-field use. For example, in U.S. Pat. No. 4,243,039, there is disclosed an emergency tourniquet consisting of a strap and a ratchet-type tensioning device, including a tensional indicating device and a pointer intended to be set by the user to indicate the time of tourniquet application.
Other mechanical restricting devices, such as, for example, disclosed in U.S. Pat. No. 5,628,723, utilize an emergency bandage tightly wrapped around the limbs of pressure dressing and may be used as a tourniquet by using a windless to twist the wrapped bandage and generate sufficient inward radial pressure on the limb to stop arterial blood flow. These prior devices have not proved to be effective or reliable.
On the other hand, pneumatic tournament cuffs have been proven to be effective for stopping arterial blood flow. However, such pneumatic tournament cuffs require a source of pressurized gas to inflate the bladder and infield sources of pressure such as hand pumps or bulbs are typically difficult to handle and may not provide a rapid enough response time in order to effectively stop arterial blood loss.
A field circulatory constriction device in accordance with the present invention suitable for self application by an injured person in order to stop arterial blood flow or loss in an injured limb generally includes a strap, a latch for coupling the strap around a limb, and a buckle for cinching the coupled strap onto the limb. This mechanical action can be performed in a very brief period of time.
In addition, a block and tackle mechanism is provided for increasing the pressure of the cinched strap onto the limb. Again, this mechanical configuration provides for a rapid and positive action in order to stop arterial blood loss. More particularly, the block and tackle mechanism may include a moving block attached to one end of the strap and a stationary block attached to the latch. A plurality of running lines extend between the moving and stationary blocks and a hauling line extends to the stationary block.
Still more particularly, the device in accordance with the present invention may include a one-way cord locking mechanism disposed at the stationary block for adjusting the hauling line. The one-way cord locking mechanism preferably includes a one-way cord lock that allows a tensioning cord to be pulled through in one direction, but not in another. The tensioning cord is connected to the hauling line, thus drawing the moving block toward the stationary block to constrict the strap about the limb.
More particularly, the one-way cord lock comprises two geared surfaces, biased towards each other to engage the tensioning cord.
Still more particularly, the buckle in accordance with the present invention includes a hook for engaging the latch and the device preferably includes a sleeve for enclosing a block and tackle mechanism to prevent entry of dirt and/or debris.
With reference to
As shown, the device 10 generally includes a strap 12 made from any suitable flexible material and a hook 40 operable for coupling the strap 12 around a users limb such as, for example, an arm or a leg.
A buckle 22 is provided for cinching a coupled strap 12, see
In a preferred embodiment, the locking head 30 is comprised of a set of locking teeth or a locking tooth disposed on the clamp. And when the clamp 23 is a biased clamp, the teeth are biased to engage the flexible shaft. In this fashion, the clamp allows movement of the strap 12 through the buckle 22 when the user desires to cinch the device around the limb but does not allow the strap 12 to return through the buckle 22 since movement of the strap will be inhibited by the teeth. In order to allow the strap 12 to return through the buckle, the clamp 23 must be released or urged against the bias to remove the teeth from engaging the strap 12.
It is evident, particularly as shown in
After coupling the hook 40 and pin 42, as shown in
As shown in
The block and tackle mechanism 50 operates in a conventional manner, including a plurality of running lines 68 and a hauling line 74. Both the running lines 68 and the hauling line 74 are preferably flexible connecting members such as non-elastic plastic chords, rope, or similar structures. The running lines 68 and the hauling line 74 may be separate lines or may optionally be a single, continuous line. In a preferred embodiment, a single line is used for both the running lines 68 and the hauling line 74, as best seen in
The running lines 68 pass back and forth between the moving block 54 and the stationary block 56. Both blocks 54 and 56 have apertures, such as the apertures 54a as seen in
Movement or pulling (such as with one hand) of the hauling line 74 in the direction of the arrow 76 of
The hauling line 74 may be locked into place with the one-way line lock 130, disposed on the stationary block 56. The hauling line 74 passes from the moving block 54 through a guide 138 and into contact with the pointed edges 132c of two locking member 132. Each locking member 132 is pivotally mounted to the stationary block 56 with screws 140 positioned through apertures 132b under cover 136. Further, each locking member 132 is biased to pivot (as shown by arrow 178) in the direction of the center of the stationary block 56, towards each other and the hauling line 74.
Due to their oblong shape and the configuration of the pointed edges 132c, the locking members allow the hauling line 74 to be pulled through the one-way lock 130 in the direction of the arrow in
If a user desires to release the hauling line 74 to decrease the overall tension caused by the constriction device 10, levers 132a on the ends of the locking members 132 may be squeezed, causing the pointed edges 132c of the locking members to pivot away from the hauling line 74. With the frictional force of the locking members 74 disengaged, the hauling line 74 is free to move in either direction. Typically, the hauling line 74 moves in the direction of the connected moving block 54 in this situation due to a directional bias of the moving block 54 away from the stationary block 56. As best seen in
As best seen in
In addition, it is noted that the elastic member 106 includes two bumps or ridges 179 that are received in corresponding receptacles of fixture 122. These bumps or ridges 179 may extend substantially the width of said elastic member 106. These bumps or ridges 179 facilitate the retention of the elastic member 106 by the fixture 122.
Preferably, a flexible sleeve 108 having a tube-like shape, seen in
Although the one-way line lock 130 is a preferred embodiment of the present invention, any mechanism may be used to selectively lock and tension the hauling line.
In addition, a guard 120 may be provided and coupled to the strap 12 by way of a fixture 122 and attached to the stationary block 56 in order to provide a spacing between the hook 40 and end 128 of the guard 120, see
In operation, a user places the constriction device 10 around a limb and latches pin 42 on hook 40. The protrusion 175 on the hook 40 serves to retain the pin 42 (and thus the buckle 42) in the hook 40. This is an added safety measure. Next, the user pulls down on the end 26 of strap 12, tightening the constriction device 10 around the limb. Finally, the user adjust the final tension of the constriction device 10 by pulling on handle 134 of hauling line 74 to increase tension or releasing the hauling line 74 with levers 132a to relieve tension. Thus, the present invention allows a user to easily achieve a desired tightness around a limb. Further, the ease of use of the present invention allows a user to engage the constriction device with only one hand, making the present invention ideal for self-use in an emergency.
Although there has been hereinabove described a specific field circulatory constriction device in accordance with the present invention for the purpose of illustrating the manner in which the invention may be used to advantage, it should be appreciated that the invention is not limited thereto. That is, the present invention may suitably comprise, consist of, or consist essentially of the recited elements. Further, the invention illustratively disclosed herein suitably may be practiced in the absence of any element which is not specifically disclosed herein. Accordingly, any and all modifications, variations or equivalent arrangements which may occur to those skilled in the art, should be considered to be within the scope of the present invention as defined in the appended claims.