Spa cover lifter and method

Abstract

A spa cover lifter for moving a spa cover from a closed position to a storage position includes a drive mechanism, a fixed base and a lifting arm assembly. The lifting arm assembly is mounted to first or second leaves of the spa cover. The lifting arm assembly is driven by the drive mechanism and is moveably mounted to the fixed base. The lifting arm assembly includes a cover pivoting assembly and a cover transporting assembly. The cover pivoting assembly is driven by the drive mechanism to move the cover from the closed position to an intermediate position and the cover transporting assembly is driven by the drive mechanism to the move the cover from the intermediate position to the storage position. The spa cover lifter has an automatic shutoff for cutting power when an obstacle is encountered. A method of moving the spa cover is also disclosed.

1 . A spa cover lifter for moving a cover from a closed position covering a mouth of a spa to a storage position exposing the mouth, the cover including a first leaf and a second leaf, the spa cover lifter comprising:
 a drive mechanism;   a fixed base; and   a lifting arm assembly mounted to one of the first leaf and the second leaf, the lifting arm assembly driven by the drive mechanism and movably mounted to the fixed base, the lifting arm assembly including a cover pivoting assembly and a cover transporting assembly, the cover pivoting assembly driven by the drive mechanism to move the cover from the closed position to an intermediate position and the cover transporting assembly driven by the drive mechanism to move the cover from the intermediate position to the storage position.   
   
   
       2 . The spa cover lifter of  claim 1  wherein the drive mechanism is comprised of a linear actuator, the linear actuator being pivotally mounted to the fixed base. 
   
   
       3 . The spa cover lifter of  claim 2  wherein the linear actuator is pivotally mounted to the fixed base by an actuator mount beam and a pivoting bracket. 
   
   
       4 . The spa cover lifter of  claim 1  wherein the lifting arm assembly further includes a cover clamp assembly removably mounted to the cover, the cover clamp assembly including a clamp, a cover clamp arm, a pivot pin and a pivot shaft. 
   
   
       5 . The spa cover lifter of  claim 4  wherein the pivot shaft is removably mounted to the cover clamp arm. 
   
   
       6 . The spa cover lifter of  claim 1  wherein the cover pivoting assembly includes a triangular linkage, a slotted bar, a first actuator bar, a second actuator bar and an actuator fitting, the cover transporting assembly includes the actuator fitting, a first bracket, an extension arm, a first linkage and a pivoting bracket, the pivoting bracket and the first linkage being pivotably mounted to the fixed base. 
   
   
       7 . The spa cover lifter of  claim 6  wherein the lifting arm assembly further includes a cover clamp assembly removably mounted to the cover, the cover clamp assembly including a clamp, a cover clamp arm, a pivot pin and a pivot shaft, the pivot shaft being pivotably mounted to the triangular linkage. 
   
   
       8 . The spa cover lifter of  claim 6  further comprising: a lock arm mounted between the cover pivoting assembly and the cover transporting assembly, the lock arm inhibiting movement of the cover pivoting assembly relative to the cover transporting assembly when the cover is proximate the intermediate position and in the storage position. 
   
   
       9 . The spa cover lifter of  claim 8  wherein the lock arm is pivotably mounted to the first bracket and the actuator fitting. 
   
   
       10 . The spa cover lifter of  claim 6  wherein the slotted bar includes a first plurality of adjustment holes along its length and the first bracket includes a second plurality of adjustment holes, the triangular linkage pivotably mounted to the slotted bar at one of the first plurality of adjustment holes and the extension arm mounted to the first bracket at one of the second plurality of adjustment holes. 
   
   
       11 . The spa cover lifter of  claim 10  further comprising: a cover clamp assembly removably mounted to one of the first leaf and second leaf, the cover clamp assembly including a cover clamp arm and the triangular linkage including a first arm, a second arm and a third arm, the cover clamp arm pivotably mounted to a terminal end of the extension arm and the third arm fixed to the cover clamp arm. 
   
   
       12 . The spa cover lifter of  claim 1  wherein the fixed base is comprised of a base plate secured to a support surface, an upstanding leg extending generally perpendicularly from the base plate and a horizontal leg positioned generally perpendicular relative to the upstanding leg, the lifting arm assembly pivotally mounted to the horizontal leg. 
   
   
       13 . The spa cover lifter of  claim 1  wherein the lifting arm assembly includes a pivoting bracket pivotally mounted to the fixed base, the drive mechanism pivotably mounted to the fixed base by the pivoting bracket. 
   
   
       14 . The spa cover lifter of  claim 1  further comprising: an arm housing covering at least portions of the drive mechanism and the lifting arm assembly. 
   
   
       15 . The spa cover lifter of  claim 1  further comprising: a lock arm mounted between the cover pivoting assembly and the cover transporting assembly, the lock arm inhibiting movement of the cover pivoting assembly relative to the cover transporting assembly when the cover is in the intermediate and storage positions. 
   
   
       16 . The spa cover lifter of  claim 1 , further comprising a safety shutoff mechanism in communication with the controller, the controller disabling the drive mechanism based upon a stop signal from the safety shutoff mechanism. 
   
   
       17 . A spa cover lifter for moving a cover from a closed position covering a mouth of a spa to a storage position exposing the mouth, the cover including a first leaf, a second leaf and a hinge mounting the first leaf to the second leaf, the spa cover lifter comprising:
 a drive mechanism;   a fixed base; and   a lifting arm assembly pivotably mounted to the fixed base and driven by the drive mechanism, the lifting arm assembly including a cover clamp assembly mounted to one of the first leaf and the second leaf of the cover, the cover clamp assembly including a first jaw, a second jaw and a cover clamp arm, the first jaw and second jaw engaging and securing the cover clamp assembly to the cover in a grasping position.   
   
   
       18 . The spa cover lifter of  claim 17  wherein the cover clamp assembly further includes a cover clamp shaft, the cover clamp arm removably mounted to the cover clamp shaft. 
   
   
       19 . The spa cover lifter of  claim 17  wherein the first jaw and the second jaw are adjustably mounted to the cover clamp arm, the first jaw including a base leg and a jaw leg, the base leg including a plurality of mounting holes for mounting the first jaw to the cover clamp arm, the cover clamp arm including slotted holes for mounting the second jaw to the cover clamp arm. 
   
   
       20 . The spa cover lifter of  claim 17  wherein the cover clamp assembly further includes a pair of pivot pins and a pivot shaft, the cover clamp arm positioned generally perpendicular relative to the pivot shaft and the pivot pins, the pivot pins positioned proximate the hinge in the grasping position. 
   
   
       21 . The spa cover lifter of  claim 20  wherein the cover clamp arm is removably mounted to the pivot shaft. 
   
   
       22 . A spa cover lifter having an automatic shutoff for cutting power to the spa cover lifter when an obstacle is encountered while moving the spa cover, the spa cover having a first leaf pivotably mounted to a second leaf, the spa cover lifter comprising:
 a lifting arm assembly mounted to one of the first and second leaves;   a drive mechanism coupled to the lifting arm assembly, the drive mechanism driving the lifting arm assembly to move the cover from a closed position to a storage position;   a controller in communication with the drive mechanism; and   a safety shutoff mechanism in communication with the controller, the controller disabling the drive mechanism based upon a stop signal from the safety shutoff mechanism.   
   
   
       23 . The spa cover lifter of  claim 22  wherein the safety shutoff mechanism includes a safety instrument mounted to the spa cover lifter and a lookup table, the controller receiving operating measurements from the safety instrument when the lifting arm assembly moves the cover from the closed position to the storage position and compares the operating measurements to predetermined values in the lookup table to determine if the operating measurements are outside of an acceptable range, the controller disabling the drive mechanism when the operating measurements are outside of the acceptable range. 
   
   
       24 . The spa cover lifter of  claim 23  wherein the safety instrument is comprised of a strain gage mounted to the lifting arm assembly. 
   
   
       25 . The spa cover lifter of  claim 24  wherein the strain gage is mounted to an actuator mount beam and the actuator mount beam is secured to a linear actuator of the drive mechanism. 
   
   
       26 . The spa cover lifter of  claim 22  wherein the drive mechanism is comprised of a linear actuator, an actuator mounting beam mounting the linear actuator to the lifting arm assembly, the strain gage mounted to the actuator mounting beam. 
   
   
       27 . The spa cover lifter of  claim 22  wherein the lifting arm assembly includes a cover clamp that engages one of the first and second leaves. 
   
   
       28 . A method of automatically cutting power to a drive mechanism of a spa cover lifter that moves a spa cover from a closed position covering a mouth of a spa to a storage position exposing the mouth of the spa, the spa cover lifter including a lifting arm assembly, a controller and a safety shutoff mechanism, the method comprising the steps of:
 a. positioning the spa cover in the closed position covering the mouth;   b. engaging the spa cover to the lifting arm assembly;   c. actuating the drive mechanism to move the lifting arm assembly and the spa cover;   d. sending a signal from the safety shutoff mechanism to the controller as the spa cover moves from the closed position to the storage position;   e. comparing the signal to a lookup table; and   f. sending a stop signal from the controller to the drive mechanism if one of the spa cover and lifting arm assembly encounters an obstacle based upon the comparison of step (e).   
   
   
       29 . The method of  claim 28  wherein the safety shutoff mechanism sends strain signals to the controller in step (d) and the controller compares the strain signals to a standardized strain lookup table in step (e), the controller sending the stop signal and eliminating power to the drive mechanism in step (f) if the strain signals are outside of a predetermined range in comparison to the lookup table.