Patent Publication Number: US-11384555-B2

Title: System, method and apparatus for opening a spa hard cover

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation application of, and claims the benefit of, U.S. patent application Ser. No. 15/895,087, filed on Feb. 13, 2018, which claims the benefit of U.S. Provisional Application Ser. No. 62/458,164, filed on Feb. 13, 2017, each of which are hereby incorporated by reference herein in their entireties. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates generally to spas and, more particularly, to manual and automated mechanisms for opening and closing a spa hard cover. 
     BACKGROUND OF THE INVENTION 
     Spas, also commonly known as hot tubs, are popular fixtures that are used in many homes. They generally include a deep, vacuum formed tub having a smooth acrylic liner that is filled with heated water and which is used for soaking and relaxation. Spas typically include water jets for massage purposes. 
     Typically, the acrylic liner is formed into shapes that provide a variety of seating arrangements within the tub. Each seat is usually equipped with hydrotherapy jets that allow a pressurized flow of water to be directed at various parts of a user&#39;s body. The water flow may be aerated for additional effect, and some or all of the jets may also automatically move or rotate, causing the changing pressure of the water on the body to provide a massage like effect. 
     Because many spas/hot tubs are located outdoors, they are often equipped with covers for enclosing the tub when not in use. These covers help prevent dirt, leaves and other debris from entering the water, and provide a safety function by preventing children and animals from falling into the water. Moreover, spa covers are often insulated so as to limit heat loss from the water when the spa is not in use, for purposes of energy efficiency and readiness of use. 
     Both soft and hard covers are known in the art. Typical hard covers generally consist of a hollow plastic shell that can be filled with an insulating foam. These covers typically include internal ribs or columns (also referred to as “kiss offs”) that extend between the top shell member and the bottom shell member of the cover to provide structural rigidity and support to the cover. These kiss-offs, while providing rigidity, can degrade the overall insulative benefits of the cover by providing a conductive means for heat to escape the spa to atmosphere. 
     In connection with the above, typical hard covers for spas may be formed using a variety of molding methods, such as through rotational molding and blow molding, as well as vacuum forming. These hard covers typically require some sort of lift mechanism to remove them from the spa. Soft covers can be manually slid off the spa and manually slid back on with significant effort. Hard covers require an assist mechanism to remove them due to the hard nature of the cover material and the increased weight over a soft cover. Existing cover lifter systems can suffer from water infiltration issues, difficulty in installation, much greater difficulty in servicing in the field do to mechanisms being installed from within the spa cabinet interior, and non-reproducibility of the lifter positioning system due to less than optimum fixturing. 
     In view of the above, there remains a need for a cover lifter system that has improved performance properties, repeatability, structural integrity, ease of installation from the outside of the cabinet frame, improved adjustability, and a related ease of service and adjustment in the field. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to provide a manual cover lift system for a spa. 
     It is another object of the present invention to provide an automated cover lift system for a spa. 
     It is another object of the present invention to provide an automated cover lift system that incorporates a friction or otherwise torque limiting breakaway that will release the drive mechanism from the cover when resistance to opening or closing is encountered by people or objects, for a spa. 
     It is another object of the present invention to provide an automated cover lift system that incorporates a friction or otherwise torque limiting breakaway that will release the drive mechanism from the cover when a person lifts up on the cover with nominative and sufficient force to break it free in an emergency or out of power situation where the spa cover needs to be opened, for a spa. 
     It is another object of the present invention to provide an automated cover lift system that incorporates a friction or otherwise torque limiting breakaway that will release the drive mechanism from the cover and will be fully restored to normal operating conditions when the cover is recycled through a normal opening and closing cycle, for a spa. 
     It is another object of the present invention to provide a cover lift system for a spa that has improved strength, rigidity and repeatability. 
     It is another object of the present invention to provide a cover lift system for a spa that has an improved resistance to water infiltration. 
     It is another object of the present invention to provide a cover lift system for a spa that is more easily installed during manufacturing of the spa. 
     It is another object of the present invention to provide a cover lift system for a spa that is more easily adjusted during manufacturing of the spa. 
     It is another object of the present invention to provide a cover lift system for a spa that can be easily removed after manufacturing of the spa and shipped in a separate box and not attached to the spa where damage can occur during transportation to the customer. 
     It is another object of the present invention to provide a cover lift system for a spa that can be easily re-installed and re-adjusted in the field. 
     These and other objects are achieved by the present invention. 
     According to an embodiment of the present invention, a cover lift system for a spa includes a lifter handle having an upper arm and a lower arm telescopically connected to the upper arm, the upper arm being configured for operative connection to a cover of a spa, and the lower arm being configured for pivotal connection to a base of the spa, and an adjuster mechanism associated with the lifter handle for selectively adjusting a length of the lifter handle to allow for use of the lifter handle with spas of varying sizes. 
     According to another embodiment of the invention, a spa includes a base having a support frame, a shell supported by the support frame, a cover member positioned atop the base, and a cover lift system mounted to an exterior-facing surface of the support frame behind a removable side panel of the base. 
     According to yet another embodiment of the present invention, a method of installing a cover lift system on a spa includes providing a lifter handle having an upper arm and a lower arm telescopically connected to the upper arm, the upper arm being configured for operative connection to a cover of the spa, and the lower arm being configured for pivotal connection to a base of the spa, and adjusting a length of the lifter handle in dependence upon a size of the spa. Adjusting the length includes at least one of extending the lower arm from the upper arm to increase the length of the lifter handle or retracting the lower arm into the upper arm to decrease the length of the handle. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention will be better understood from reading the following description of non-limiting embodiments, with reference to the attached drawings, wherein below: 
         FIG. 1  is a perspective view of a cover lift system according to an embodiment of the invention, viewed from exterior to a spa. 
         FIG. 2  is another perspective view of the cover lift system of  FIG. 1 , viewed from interior to the spa. 
         FIG. 3  is another perspective view of the cover lift system of  FIG. 1 . 
         FIG. 4  is an exploded perspective view of the cover lift system of  FIG. 1 . 
         FIG. 5  is a plan view of a lifter handle of the cover lift system of  FIG. 1 . 
         FIG. 6  is a transparent, plan view of the lifter handle of  FIG. 5 . 
         FIG. 7  is an enlarged, transparent plan view of a portion of the lifter handle of  FIG. 5 , shown an adjuster mechanism thereof. 
         FIG. 8  is perspective view of a coupling member of a crossbar of the cover lift system of  FIG. 1 . 
         FIG. 9  is a perspective view of a coupling member of an upper arm of the cover lift system of  FIG. 1 . 
         FIG. 10  is a perspective view of a shaft insert of a lift mechanism. 
         FIG. 11  is a perspective view of a coupling member of a lower arm of the cover lift system of  FIG. 1 . 
         FIG. 12  is a perspective view of an interface between the coupling member of the lower arm and the shaft insert. 
         FIG. 13  is a perspective view of a ball stud holder of the cover lift system of  FIG. 1 . 
         FIG. 14  is another perspective view of the ball stud holder of  FIG. 13 . 
         FIG. 15  is a plan view of a ball stud of the cover lift system of  FIG. 1 . 
         FIG. 16  is a side plan view of a spa having the cover lift system installed therein, with a side panel removed. 
         FIG. 17  is a perspective view of a spa having the cover lift system installed therein, with a side panel removed. 
         FIG. 18  is a perspective view of a linear actuator assembly for automatically opening and closing a spa cover. 
         FIG. 19  is an elevational view of the linear actuator assembly of  FIG. 18   
         FIG. 20  is a perspective view of a friction plate torque limiter of the linear actuator assembly of  FIG. 19 . 
         FIG. 21  is an exploded, perspective view of the torque limiter of  FIG. 20 . 
         FIG. 22  is an elevational view of a linear actuator assembly according to another embodiment of the invention. 
         FIG. 23  is a perspective view of a ball/spring torque limiter of the linear actuator assembly of  FIG. 22 . 
         FIG. 24  is an exploded, perspective view of the torque limiter of  FIG. 23 . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to  FIGS. 1-4 , a cover lift system  10  according to an embodiment of the present invention is illustrated. The cover lift system  10  includes a lifter handle  12  having a generally tubular first, upper arm  14  and a generally tubular, second lower arm  16  telescopically received by the upper arm  14 . The upper arm  14  is generally L-shaped and includes a hollow connector member  18  that extends generally perpendicularly from an upper end of the upper arm  14 , which is configured to facilitate the attachment of a crossbar  20  of the cover lift system  10  to the upper arm  14  in the manner discussed hereinafter. Similarly, the lower arm  16  is generally L-shaped and has a hollow connector member  22  that extends generally perpendicularly from a lower end of the lower arm  16 , which is configured to facilitate coupling of a lift-assist mechanism of the cover lift system  10  to the lower arm  16 , in the manner discussed hereinafter. 
     With specific reference to  FIGS. 5-7 , the lifter handle  12  includes an adjuster mechanism  24  for selectively adjusting a length of lifter handle  12  and, in particular, a distance, d, between the connector member  18  of the upper arm  14  and the connector member  22  of the lower arm  16 . In particular, the adjuster mechanism  24  is selectively actuatable to either draw the connector members  18 ,  22  towards one another to shorten the distance, d, or to move the connector members  18 ,  22  away from one another to lengthen the distance, d. In an embodiment, the adjuster mechanism  24  is a linear actuator such as, for example, a leadscrew. In particular, as illustrated in  FIG. 7 , the adjuster mechanism  24  may include a leadscrew  26  mounted in fixed longitudinal position within the hollow upper arm  14  via fixing member  28 . The leadscrew  26  has a drive head  30  configured for mating coupling with a hex socket (not shown) that enables the leadscrew  26  to be rotated within the upper arm  14  and fixing member  28 . Within the upper end of the lower arm  16  is fixedly mounted a nut  32  having a threaded bore  34  for threadedly receiving a distal end  36  of the leadscrew  26 . 
     In operation, a socket (not shown) may be inserted into an open, upper end  38  of the upper arm  14  and engaged with the drive head  30  of the leadscrew  26  to rotate the leadscrew  26  while the nut  32  within the lower arm  16  remains stationary. Depending on the direction of rotation of the leadscrew  26 , the nut  32  is either drawn up the leadscrew towards the head  28 , thereby drawing the lower arm  16  further into the upper arm  14  and decreasing the distance, d, or advanced towards the distal end  36  of the leadscrew  26 , thereby extending the lower arm  16  from the upper arm  14  and increasing the distance, d. While the adjuster mechanism  24  is shown and described herein as taking the form of a leadscrew, other types of linear actuators known in the art may also be utilized without departing from the broader aspects of the invention. Importantly, the adjuster mechanism  24  allows for the selective adjustment of the distance, d, between the connector member  18  of the upper arm  14  and the connector member  22  of the lower arm  16 , enabling the cover lift system  10  to be utilized with a range of spa sizes. 
     Referring now to  FIGS. 6-9 , the hollow connector member  18  of the upper arm  14  contains a first mechanical coupling member  40  fixedly mounted therein, which is configured to matingly engage a corresponding second mechanical coupling member  42  fixedly mounted within the crossbar  20 .  FIGS. 6 and 7  illustrate the first coupling member mounted within the hollow connector member  18  of the upper arm  14 . As illustrated in  FIGS. 8 and 9 , the respective coupling members  40 ,  42  may have a shape and size that corresponds to the shape and size of the interior of the hollow connector member  18  of the upper arm  14  and the crossbar  20 , respectively. As best shown in  FIGS. 8 and 9 , for example, the coupling members  40 ,  42  may be substantially cylindrical in shape. One of the coupling members, for example, coupling member  42  within the crossbar  20 , may include a key  44  configured to be received in a corresponding slot  46  of the coupling member  40  of the upper arm  14  to connect the crossbar  20  to the upper arm  14  of the lifter handle  12 . Bores  48 ,  50  may extend through the coupling members  40 ,  42 , one or both of which may be threaded. The engagement of the key  44  within the slot  46  prevents relative rotation of the crossbar  20  with respect to the hollow connector member  18  so that a rotational covering or uncovering force can be transmitted from the lifter handle  12  to the crossbar  20  (and ultimately to a cover member), as discussed hereinafter. 
     Turning now to  FIGS. 10-12 , the hollow connector member  22  of the lower arm  16  contains a third mechanical coupling member  52  fixedly mounted therein, which is configured to matingly engage a shaft insert  54  of a lifter mechanism (and shaft  55  thereof), as described in detail hereinafter. As illustrated in  FIGS. 10 and 11 , the coupling member  52  and shaft insert  54  may be substantially cylindrical in shape. Importantly, one of the coupling member  52  and shaft insert  54  (e.g., the shaft insert  54  in  FIG. 10 ) may have a stepped geometry in the form of a key  56  at one end thereof that tapers to a narrow tip. This stepped key  56  is configured to be received in a correspondingly shaped stepped slot  58  formed in an end of the other of the coupling member  52  and the shaft insert  54  (e.g. the coupling member  52  in  FIG. 11 ). Bores  60 ,  62  may extend through the coupling member  52  and shaft insert  54 , one or both of which may be threaded. Importantly, the geometry of the interfaces (namely, the stepped key  56  and corresponding keyway or slot  58 ) allow the lifter handle  12  to be inserted onto the lifter mechanism shaft  54  with up to about a 20 degree rotational misalignment and still be drawn together with a bolt (through bores  60 ,  62 ) that will pull them to proper alignment.  FIG. 12  illustrates how a successful mating and interlocking between the coupling member  52  and shaft insert  54  can be achieved even with a substantial misalignment between the two parts. 
     This feature not only makes it very easy to assemble these parts during manufacturing, but it allows for servicing in the field without the necessity of removing the sides of the spa. Moreover, when the system is fully assembled, the lifter mechanism (not shown) is loaded with an air spring that causes it to rotate about 18 degrees out of alignment with the lifter handle  12  when the cover is lying flat atop the spa. This coupling design allows the non-aligned coupling member  52  and shaft insert  54  to be mated together and pulled into alignment simply by tightening a bolt that extends through both parts. 
     Referring once again to  FIGS. 1-3 , the cover lift system  10  also includes a generally planar mounting bracket  64  having a plurality of apertures  66  through which fasteners may be inserted to couple the cover lift system  10  to a frame of a spa. For example, in an embodiment, the mounting bracket  64  may be mounted to an upright  68  or corner strut of a frame of a spa. As best shown in  FIG. 2 , the shaft insert  54 , which is mated with the coupling  52  within the connector member  22  of the lower arm  16 , extends through an aperture  70  in the mounting bracket  64  and through the frame upright  68 . The end of the shaft insert  54  is configured for operative connection to the upper end of a lift assist mechanism (not shown), such as a gas spring, that provides an assisting force for a covering and/or uncovering operation. 
     As shown in  FIG. 2-4 , the cover lift system  10  further includes a pivot mechanism  72  operatively connected to a lower end of the mounting bracket  64  on the inside surface thereof and which extends though the frame upright  68  to receive a lower end of the lift assist mechanism (e.g., a gas spring).  FIGS. 13-15  more clearly show the configuration of the pivot mechanism  72 . The pivot mechanism  72  includes a ball stud holder  74  and a ball stud  76 . The ball stud holder  74  is generally cylindrical in shape and has a pair of opposed wrenching flats  78  on one end thereof. The ball stud holder  74  also includes a threaded center bolt hole  80  that is configured to receive a bolt for attaching the ball stud holder  74  to the mounting bracket  64  using a bolt, and a threaded aperture  82  on the end with the wrenching flats  78  for threadedly receiving a correspondingly threaded portion of the ball stud  76 . As illustrated in  FIG. 14 , the threaded aperture  82  for mounting the ball stud  76  is offset from a central axis of the ball stud holder  74 . 
     As indicated above, the pivot mechanism  72  holds the lower end of the lift assist mechanism (e.g., the gas spring). The offset of the ball stud  76  from the central axis of the ball stud holder  74  allows the ball stud  76  to be rotated out of position around the center bolt (not shown) that is received through the center bolt hole  80 . The lift assist mechanism can then be attached by hand to the ball stud  76  with little effort. A wrench can then be used to engage the wrenching flats  78  to rotate the ball stud into position, exerting a compression load on the gas spring of the lift assist mechanism. This is accomplished by aligning a smaller threaded hole  84  on the other end of the ball stud holder  74  (that is likewise offset from the central axis) with a hole  86  in the bracket  64  and inserting a bolt to hold it in place. In this manner, the gas spring of the lift assist mechanism can be installed an compressed with very little effort in tightly enclosed space within the spa cabinet. 
       FIGS. 16 and 17  illustrate the cover lift system  10  of the present invention installed within a spa  100 . In particular, spa  100  incudes a pair of cover lift systems  10  for covering and uncovering first and second cover members  102 ,  104 , respectively. As indicated above, and as shown in  FIGS. 16 and 17 , each cover lift system  10  is attached to the outside surface of the frame uprights  68  of the frame of the spa  100 . The crossbars extend through the cover member  102 ,  104  in order to transmit rotational movement of the lifter handle  12  to the cover members  102 ,  104 , to remove the cover members  102 ,  104  from atop the spa during an uncovering operation, and to replace the cover members  102 ,  104  atop the spa during a covering operation. 
     In particular, in use, a gas spring mounted on the interior side of the bracket  64  provides a lift-assist force for both an uncovering and covering operation. In particular, when the cover is in a closed position, the lift-assist mechanism exerts a generally upward force on the cover member. To uncover the spa, a user grasps the lifter handle  12  and, in particular, the upper arm  14  thereof, and rotates the lifter handle  12  about a horizontal axis that extends through the connector member  22  of the lower arm  16 . This rotational force is transmitted through the lifter handle  12  and the crossbar  20  that extends through the cover member, causing the cover member to slide from atop the spa to an uncovered position. 
     Importantly, the cover lift system  10  is configured such that the brackets  64  and other components thereof are hidden under the spa cabinet side panels (which are removed in  FIGS. 16 and 17 ) during use. The cover lift system  10 , however, can be easily installed and serviced in the field simply by removing the side panels. 
     Referring now to  FIGS. 18 and 19 , a linear actuator assembly  200  that can be used to automatically open and close the spa cover members  102 ,  104  is shown (instead of manual operation). The linear actuator assembly  200  mounts internally to the spa frame and connects to the cover lifter system  10  described above. The electrically driven linear actuator drives a chain  202  that rotates the lifter handle  12 . This automated lift assembly can be chain driven from a linear actuator  204 , as shown, or can be linkage driven with or without the chain with simple linkages such as a crank rocker configuration to rotate the lifter handle  12  and open the spa cover. With reference to  FIGS. 20 and 21 , the linear actuator assembly  200  may include a friction plate type torque limiter  210  used for breakaway safety. 
     With reference to  FIGS. 22-24 , in an embodiment, an automated lifter mechanism  300  may alternatively use mechanical linkages  302 ,  304  connecting the linear actuator  304  with the disk  306  for rotatably driving the disk (and thus lifter handle  12 ). As shown in  FIGS. 23 and 24 , this design may incorporate a ball/spring torque limiter  310  for use as a breakaway safety mechanism. 
     In either implementation, the torque limiting breakaway mechanism functions to release the drive mechanism from the cover when resistance to opening or closing is encountered by people or objects. In addition, the toque limiting breakaway mechanism is configured to decouples the drive mechanism from the cover when a person lifts up on the cover with nominative and sufficient force to break it free in an emergency or out of power situation where the spa cover needs to be opened. In an embodiment, the torque limiting breakaway mechanism will release the drive mechanism from the cover and will be fully restored to normal operating conditions when the cover is recycled through a normal opening and closing cycle. 
     Although this invention has been shown and described with respect to the detailed embodiments thereof, it will be understood by those of skill in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiments disclosed in the above detailed description, but that the invention will include all embodiments falling within the scope of this disclosure.