Abstract:
A device that releases an operating collar from an open position on the mast of an opened beach or patio umbrella in the presence of a strong wind, allowing the umbrella canopy to close thereby diminishing the wind force acting on the umbrella. The device includes a locking pin and an associated biasing mechanism. In a working configuration of the device, the pin is exposed for insertion through certain holes in the mast. A distal end of the mechanism faces the mast while a proximal end of the mechanism applies a bias force to a proximal end of the pin. The collar rests on the inserted pin with enough force to overcome the bias force tending to eject the pin. When the collar is urged to rise because of a strong wind acting on the umbrella, the pin ejects thus freeing the collar to move downward as the umbrella canopy closes.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   This invention relates to locking and release mechanisms, particularly for use with beach or patio umbrellas. 
   2. Discussion of the Known Art 
   Large beach or patio umbrellas may become dangerous projectiles in the presence of strong winds, if the umbrellas are not properly weighted or anchored to the ground. Serious personal injury and substantial property damage can occur under such circumstances. Accordingly, there is a need for a mechanism or device that will release an opened umbrella canopy to close quickly in the presence of a strong wind, in order to reduce the overall wind force acting on the umbrella to a safe level. 
   U.S. Pat. No. 6,247,483 (Jun. 19, 2001) discloses an automatic locking and release device for a beach umbrella. The device includes a spring-loaded locking bar that is mounted inside of an umbrella mast for sliding movement through an opening in the mast. A lever is also pivotally mounted inside the mast. One end of the lever contacts an inside end of the locking bar, while an opposite end of the lever has a cam that swings through a slot in the mast a certain distance above the locking bar. In use, when an operating collar or runner on the mast is moved upward to open the umbrella, the runner urges the lever cam into the mast and causes the opposite end of the lever to advance the locking bar out from inside of the mast. 
   When the runner is released to rest on the locking bar, further downward movement of the runner is blocked by the bar so the umbrella will stay open. When the runner is raised again to engage the lever cam, the opposite end of the lever interacts with the locking bar in such manner that the bar retracts fully into the mast. The runner is then free to descend on the mast without obstruction by the bar, allowing the umbrella to close. 
   U.S. Pat. No. 2,937,653 (May 24, 1960) relates to a supporting and release catch for the runners of beach umbrellas. Like the &#39;483 patent, the catch of the &#39;653 patent includes a lever that is mounted to pivot inside of an umbrella mast. In a rest position, an arm on an upper portion of the lever projects out through a slot in the mast. When the runner is moved up into contact with the arm, a hook on a lower portion of the lever is swung outside of the mast through a corresponding slot. If the runner is suddenly released, it engages the hook and remains in such a position that the umbrella stays open. If, however, the runner is raised and then slowly lowered on the mast, the lever hook is swung by gravity fully into the mast. The runner is then free to move lower on the mast as the umbrella is closed. 
   As noted, the mechanisms of the &#39;483 and the &#39;653 U.S. patents are fairly complex and are mounted inside of an umbrella mast. Therefore, the mechanisms can not be easily applied to most conventional, existing beach or patio umbrellas. Moreover, the known mechanisms may not respond quickly enough to ensure that an umbrella runner or collar will descend freely on the umbrella mast and allow an opened canopy to close as soon as a strong wind starts to lift the canopy. Accordingly, there is a need for a safety device that can work with existing beach and patio umbrellas, and respond to potentially dangerous wind conditions by quickly releasing the umbrella runner from an open position at which it is set on the umbrella mast. 
   SUMMARY OF THE INVENTION 
   A safety locking and release device is provided for a beach or patio umbrella having a top canopy, a mast for supporting the canopy, an operating collar that runs on the mast with canopy support elements linked to the collar for opening or closing the canopy as the collar is raised or lowered, and the mast has one or more holes for receiving a locking pin that blocks the collar from dropping below an open position on the mast. 
   The safety device includes a locking pin having a proximal end and a distal end, and the pin is formed for insertion through the holes in the mast. A biasing mechanism is mounted on the locking pin, and the mechanism is arranged so that when in an operating configuration, the mechanism exposes the pin for insertion through the holes in the umbrella mast to a position where a distal end of the mechanism confronts the mast, and a proximal end of the mechanism applies a bias force to the proximal end of the pin in a direction that tends to withdraw the pin from the mast. 
   The operating collar rests on the inserted locking pin with enough force to overcome the action of the bias force applied to the proximal end of the pin. The pin ejects from the mast when the collar is urged upward by the canopy support elements in response to a wind force acting on the umbrella. Thus, the collar is released from the open position on the mast, and is free to run down the mast as the canopy closes and the wind force on the umbrella is thereby diminished. 
   For a better understanding of the invention, reference is made to the following description taken in conjunction with the accompanying drawing and the appended claims. 

   
     BRIEF DESCRIPTION OF THE DRAWING 
     In the drawing: 
       FIG. 1  is an elevational view, partly in section, of a beach or garden patio umbrella with the inventive safety device in place; 
       FIG. 2  is a side view, partly in section, of a first embodiment of a safety locking and release device according to the invention; 
       FIG. 3  is a side view, partly in section, of a second embodiment of the inventive device; and 
       FIG. 4  is a side view, partly in section, of a third embodiment of the inventive device. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1  shows an umbrella safety locking and release device  10  according to the invention, as applied to a typical beach or garden patio umbrella  12 . The umbrella  12  includes a top covering or canopy  14  that is supported by an umbrella mast  16  an upper portion of which is shown in the figure. A lower portion of the mast  16  (not shown) is typically secured in the ground, or to a weighted base fixture. 
   When the umbrella  10  is in an open condition depicted by solid lines in  FIG. 1 , and a wind force W is acting upward on the open canopy  14 , forces tending to lift the umbrella  12  out of the ground or base fixture are developed at the top of the mast  16 . Therefore, if the lower portion of the mast  16  is not adequately weighted or anchored in the ground, the umbrella  12  can become airborne with the potential of causing serious personal injury and property damage. 
   The umbrella  12  also has an associated operating runner or collar  18  that is mounted coaxially on the mast  16  to run upward or downward, and a number of support elements  20  that extend radially of the collar  18  to open or close the canopy  14  when the collar is raised or lowered on the mast  16  using, for example, a conventional pull cord and pulley arrangement  21 . In the disclosed embodiment, ends of the support elements  20  remote from the collar  18  are pivoted to corresponding canopy support ribs  22  that extend radially from a circular flange at the top of the mast  16 , beneath the center of the canopy  14 . It will be understood that components of the wind force W acting upward on the open canopy  14  are transmitted through the canopy support ribs  22  and support elements  20  to the collar  18 , and that such forces will tend to raise the collar from its normal open position with respect to the mast  16 , as depicted by arrow R in  FIG. 1 . 
   When opening the umbrella  12  from a closed or storage condition represented by dashed lines in  FIG. 1 , the collar  18  is run upward on the mast  16  by way of, e.g., the cord and pulley arrangement  21  until the collar is at a position just above a pair of diametrically opposed holes  24   a ,  24   b  formed in the wall of the mast. An elongate locking pin  40  of the device  10  (see  FIG. 2 ) is inserted through the holes  24   a ,  24   b  from outside of the mast  16 , and the collar  18  is released to rest on the inserted pin  40 . It will be understood that the collar  18  will exert a downward force on the pin  40  to counteract the force being applied through the support elements  20  to maintain the canopy  14  in a normal open condition. 
     FIG. 2  is a side view of a first embodiment of a safety locking and release device  10  according to the invention. The device  10  includes the locking pin  40  which may be formed of metallic or other sturdy material sufficient to withstand the downward force exerted by the umbrella collar  18  without shearing, when the umbrella canopy  14  is opened and the collar is released to rest on the pin as explained above. As seen in  FIG. 2 , the device  10  has an associated biasing mechanism  42  that is mounted on the pin  40 . The mechanism  42  has a distal end (at the left side of the drawing) in the form of, for example, a flat plate  44  having an opening  44   a  through which the shaft of the locking pin  40  can slide freely. The plate  44  of the biasing mechanism may therefore be displaced from a rest position shown in  FIG. 2  to an operating position at which the plate  44  is located near the proximal end of the pin  40  (at the right side of the drawing; see arrow B). Therefore, in the operating position of the plate  44 , a substantial portion of the pin  40  from its distal end is exposed for insertion through the mast holes  24   a ,  24   b.    
   The biasing mechanism  42  also has a proximal end, for example, a washer or plate  46  that is fixed or otherwise captured at the proximal end of the locking pin  40 . A biasing element which may be in the form of a coil spring  48  is disposed coaxially on the pin  40 , and the distal and proximal ends of the spring  48  are fixed to the distal and proximal ends  44 ,  46  of the mechanism  42 . Alternatively, the proximal end of the spring  48  may be fixed directly to the proximal end of the locking pin  40  by a weld or other conventional fastening technique. 
   In use of the device  10 , the proximal end of the locking pin  40  may be grasped manually, and the distal end of the pin  40  is aligned with the mast holes  24   a ,  24   b  after the umbrella collar  18  is raised above the holes. Next, the proximal end of the pin  40  is urged toward the mast to insert the pin preferably through both of the diametrically opposed holes  24   a ,  24   b , while the distal end (e.g., plate  44 ) of the biasing mechanism  42  confronts the outside circumference of the mast  16 . The device  10  then assumes an operating configuration in which the distal end of the biasing mechanism  42  is displaced toward the proximal end of the locking pin  40  to compress the spring  48 , and the proximal end of the biasing mechanism  42  applies a determined bias force from the compressed spring  48  to the proximal end of the pin  40  that tends to withdraw or eject the pin  40  out of the mast. The umbrella collar  18  is then lowered to rest on the inserted locking pin  40 . It will be understood that as long as the collar  18  exerts enough force on the pin  40  to overcome the bias force tending to eject the pin, the pin will stay in place in the mast  16  to block downward movement of the collar  18 , thereby keeping the umbrella  12  in a desired open condition. 
   As soon as the wind force W ( FIG. 1 ) acting on the opened umbrella canopy  14  is strong enough to urge the collar  18  to rise off of the locking pin  40 , as explained above, the force applied by the collar  18  on the locking pin  40  is no longer sufficient to overcome the bias force applied by the mechanism  42  to withdraw the pin. Therefore, the pin  40  is quickly ejected out of the mast  16 , and the collar  18  is free to descend as the canopy collapses and the wind force W acting on the umbrella  12  diminishes accordingly. 
     FIG. 3  is a side view of a second embodiment of a safety locking and release device  110  according to the invention. Elements of the device  110  that are the same or similar to elements of the device  10  in  FIG. 2 , have corresponding reference numerals increased by 100. 
   In the device  110 , a leaf spring  148  is substituted for the coil spring  48  as a biasing element of biasing mechanism  142  in  FIG. 3 . Operation of the device  110  of  FIG. 3  is in other respects the same as that of the device  10  in  FIG. 2 . 
     FIG. 4  is a side view of a third embodiment of a safety locking and release device  210  according to the invention. The device  210  includes a biasing mechanism  212  having an elongated hollow tubular housing  214 , and a locking pin  240  mounted for axial sliding movement inside of the housing  214 . When the device  210  is in a rest condition shown in  FIG. 4 , a distal end of the pin  240  protrudes minimally from an opening in a distal end wall  216  of the housing  214 . A biasing element, e.g., a spring  218 , has one end connected to the proximal end of the locking pin  240 , and the opposite end of the spring  218  is connected to a proximal end wall  220  of the housing  214 . A stem  222  extends radially from the proximal end of the locking pin  240 , and a tip  222   a  of the stem protrudes through an axial slot  224  in the circumference of the housing  214 . 
   In use of the device  210 , the tip  222   a  of the stem  222  on the locking pin  240  is advanced in the direction of the distal end wall  216  of the housing  214 , thereby tensioning the spring  218  and exposing a substantial portion of the pin  240  from the distal end of the pin for insertion through the umbrella mast holes  24   a ,  24   b . In such an operating configuration for the device  210 , the tensioned spring  218  or equivalent biasing element applies a bias force to the proximal end of the pin  240  that will quickly eject the inserted pin from the mast openings  24   a ,  24   b  if the collar  18  is urged upward from its rest position on the pin. 
   The magnitudes of the bias forces to be applied to the locking pins  40 ,  140 ,  240  in the embodiments of  FIGS. 2 ,  3  and  4 , can be determined by one skilled in the art and will depend, among other factors, on the physical characteristics of the particular material(s) used to form the pins, and measurements of typical forces applied by the collar  18  when the umbrella is opened and the collar is released to rest on the inserted pin. To meet a variety of applications, the disclosed devices  10 ,  110 ,  210  may be modified using conventional techniques so that the bias forces produced by compressing or tensioning the spring elements of the various biasing mechanisms are adjustable over preset ranges. 
   Also, while it is important that upon ejection of the locking pin of the device from the mast  16  the device is free to drop toward the ground and out of the path of the umbrella collar  18 , a part (e.g., the proximal end of the locking pin  40 , or the end wall  220 ) may be linked via a flexible wire or cord to another part of the umbrella  12  so that the device is not easily lost once it has been deployed. 
   While the foregoing represents preferred embodiments of the invention, it will be understood by those skilled in the art that various modifications and changes may be made without departing from the spirit and scope of the invention, and that the invention includes all such modifications and changes as come within the scope of the following claims.