Patent Publication Number: US-9840310-B2

Title: Marine suspension system

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Patent Application No. 62/126,932 filed 2 Mar. 2015. 
    
    
     FIELD 
     The present invention relates to a marine suspension system. More particularly, the present invention relates to a marine suspension system for use in high-speed watercraft. 
     BACKGROUND 
     High-speed small boats are used in a variety of applications and are particularly useful in military operations, and search and rescue operations. When fast-moving small watercraft encounter even moderately disturbed water, the passengers are subjected to significant forces. At high-speed, in waves of any appreciable size, small watercraft tend to be subjected to rapid and simultaneous vertical and horizontal acceleration and deceleration. 
     When a boat moving at high speed impacts the crest of a wave, the boat tends to simultaneously pitch upwards and decelerate, and when it passes over or through the crest and encounters the trough, the boat tends to pitch downwards and accelerate. Al high speed, each pitching and acceleration/deceleration cycle may be measured in seconds, such that passengers are subjected to rapid and extreme acceleration and deceleration and the associated shock, which is commonly quantified. in terms of multiples of g, a “g” being a unit of acceleration equivalent to that exerted by the earth&#39;s gravitational field at the surface of the earth. The term g-force is also often used, but it is commonly understood. to mean a relatively long-term acceleration. A short-term acceleration is usually called a shock and is also quantified in terms of g. 
     Human tolerances for shock and g-force depend on the magnitude of the acceleration, the length of time it is applied, the direction in which it acts, the location of application, and the posture of the body. When vibration is experienced, relatively low peak g levels can be severely damaging if they are at the resonance frequency of organs and connective tissues. In high-speed watercraft, with the passengers sitting in a conventional generally upright position, which is typically required, particularly with respect to the helmsperson and any others charged with watchkeeping, upward acceleration of the watercraft is experienced as a compressive force to an individual&#39;s spine and rapid deceleration tends to throw an individual forward. 
     Shock absorbing systems for high-speed boats are known. For example, U.S. Pat. No. 6,786,172 (Loftier—Shock absorbing boat) discloses a horizontal base for supporting a steering station that that is hingedly connected to the transom to pivot about a horizontal axis. The base is supported by spring bias means connected to the hull. 
     Impact attenuation systems for aircraft seats are also known, as disclosed in: U.S. Pat. No. 4,349,167 (Reilly—Crash load attenuating passenger seat); U.S. Pat. No. 4,523,730 (Martin—Energy-absorbing seat arrangement); U.S. Pat. No. 4,911,381 (Cannon et al.—Energy absorbing leg assembly for aircraft passenger seats); U.S. Pat. No. 5,125,598 (Fox—Pivoting energy attenuating seat); and U.S. Pat. No. 5,152,578—Kiguchi—Leg structure of seat for absorbing impact energy. 
     Other seat suspension systems are also known, as disclosed in: U.S. Pat. No. 5,657,950 (Han et al.—Backward-leaning-movement seat leg structure); U.S. patent application Ser. No. 10/907,931 (App.) (Barackman et al.—Adjustable attenuation system for a space re-entry vehicle seat); U.S. Pat. No. 3,572,828 (Lehner—Seat for vehicle preferably agricultural vehicle); U.S. Pat. No. 3,994,469 (Swenson et al.—Seat suspension including improved damping means); and U.S. Pat. No. 4,047,759 (Koscinski—Compact seat suspension for lift truck). 
     SUMMARY 
     In one aspect, the present invention provides a suspension system for a suspended seat module on a high-speed water vessel having a usual direction of travel, the suspension system including: a shock absorbing assembly for resiliently suspending a seat module relative to a vessel, wherein the shock absorbing assembly tends to cause the seat module to remain in an upper at-rest position and to return to the at-rest position on cessation of a force causing the seat module to move generally vertically towards a bottom position; a suspension module configured to constrain the seat module to linear movement; and a support assembly for supporting portions of the seat module distal from the seat module, and configured to resist athwart movement of same. 
     The support assembly may include a spar assembly interconnected between the suspension module and the seat module wherein the connection between the spar assembly and one of the suspension module and the seat module permits fore and aft movement of the spar assembly relative to the one of the suspension module and the seat module. 
     The suspension system may include a shock absorber interposed between one of: the spar assembly and the seat module; and the spar assembly and the suspension module. 
     SUMMARY OF THE DRAWINGS 
       FIG. 1  is a perspective view of a suspended seat module embodiment of the present invention having two spars, a slide assembly and a shock absorber interconnected between the helm/control module and the slide assembly, shown in the upper at-rest position. 
       FIG. 2  is a side clew Lion view of the embodiment of  FIG. 1 , shown in the upper at-rest position. 
       FIG. 3 , is a rear elevation view of the embodiment of  FIG. 1 , shown in the upper at-rest position. 
       FIG. 4 , is a perspective view of the embodiment of  FIG. 1 , shown in the bottom position. 
       FIG. 5  is a side clew Lion view of the embodiment of  FIG. 1 , shown in the bottom position. 
       FIG. 6  is a rear elevation view of the embodiment of  FIG. 1 , shown in the bottom position. 
       FIG. 7  is a perspective isolation from-below view of the slide assembly and shock absorber of the embodiment shown in  FIG. 1 . 
       FIG. 8  is a perspective isolation from-below view of the slide assembly, shock absorber and spars of the embodiment shown in  FIG. 1 . 
       FIG. 9  is a perspective isolation from-below view of the slide assembly, shock absorber and spars of the embodiment shown in  FIG. 1 . 
       FIG. 10  is side clew Lion view of a suspended seat module embodiment of the present invention having two spars and a slide assembly (but no shock absorber), shown in the upper at-rest position. 
       FIG. 11  is a perspective isolation from-below view of the slide assembly and spars of the embodiment shown in  FIG. 10 . 
       FIG. 12  is a side elevation view of a suspended seat module embodiment of the present invention having a single spar member, a slide assembly and a shock absorber interconnected between the spar member and the deck mount, shown in the upper at-rest position. 
       FIG. 13  is a perspective isolation from -below view of the slide assembly, spar member and shock absorber of the embodiment shown in  FIG. 12 . 
       FIG. 14  is a side elevation view of a suspended seat module embodiment of the present invention having two spars, a pivoting assembly and a shock absorber interconnected between the helm/control module and the pivoting assembly, shown in the upper at-rest position. 
       FIG. 15  is a partially exploded perspective isolation view of the pivot block, pivot pin assembly and shock absorber of the embodiment shown in  FIG. 14 . 
       FIG. 16  is a perspective isolation from-below view of the pivot block, pivot pin assembly, shock absorber and spars of the embodiment shown in  FIG. 14 . 
       FIG. 17  is a perspective isolation view of the guide rail assembly, carriage and strut shown in the upper at-rest position. 
       FIG. 18  is a perspective isolation view of the guide rail assembly, carriage and strut shown in the bottom position. 
       FIG. 19  is a sectional view of the guide rail assembly, carriage and strut, with the section taken perpendicular to the longitudinal axis of the channels. 
    
    
     DETAILED DESCRIPTION WITH REFERENCE TO THE DRAWINGS 
     In this specification, including the claims, terms conveying an absolute direction (for example, up, down, vertical etc.) or absolute relative positions (for example, top, bottom etc.) are used for ease of understanding and such absolute directions and relative positions may not always pertain. As well, in this specification, including the claims, terms relating to directions and relative orientations on a watercraft, for example, port, starboard, forward, aft, fore and aft (which when used herein means a generally horizontal direction generally parallel to the direction of travel of the vessel), bow, stern, athwart (which when used herein means a generally horizontal direction generally perpendicular to the direction of travel of the vessel) etc. are used for ease of understanding and such terms may not always pertain. 
     As well, in this specification, including the claims, the terms “roll” and “pitch” are used to refer to movement relative to an imaginary line parallel to the nominal direction of travel of the vessel or object, and passing through the center of mass of the vessel or object, with “roll” being quasi-pivotal or quasi-rotational lateral movement with respect to the imaginary line, and “pitch” being a generally vertical angle of displacement (e.g. bow up or bow down) caused by a vertical force applied at a distance from the center of mass. 
     Suspended seat module embodiments for at aching to a deck  200  (i.e., a suitable section of a water vessel) are shown in the drawings. 
     The suspended seat module embodiments include a main suspension module  202 , a seat module  204 , and interposed between the main suspension module  202  and the seat module  204 , a strut  206  and a support assembly  208 . 
     The main suspension module  202  includes a deck mount  220  (preferably aluminum) configured for attaching to the deck  200 , and projecting upwards (preferably angled rearward from vertical) from the deck mount  220 , a guide rail assembly  221 . The guide rail assembly  222  includes two spaced-apart opposed channels  224 . The guide rail assembly  222  is preferably anodized aluminum and may be bolted to the deck mount  220 . 
     The seat module  204  includes a seat  230  (preferably comprising foam cushions covered in a sturdy upholstery material), a forward projecting helm/control module  232  (which may be any one of, or combinations of a vessel control module, a communications module, a navigation module or other user specific module, e.g., a surveying module), with foot pegs  234  on which a user may rest his or her feet during use, and a carriage  236 . The seat  230  and helm/control module  232  preferably have an aluminum frame and may include a storage box made from welded aluminum sheet metal. 
     The carriage  236  is preferably anodized aluminum and includes anodized aluminum axles supporting rollers  238 , preferably made from hard, low-friction plastic acetal), and sized and oriented to slide within the channels  224 , so as to restrict the seat module  204  to movement parallel to the channels  224 . 
     The strut  206  is interconnected between the main suspension module  202  and the carriage  236 . Preferably, the strut  206  is attached to the carriage  236  via a stainless steel bracket bolted to the carriage  236 , and the strut  206  is attached to the main suspension module  202  via a direct attachment to the guide rail assembly  222 . The strut  206  may be any suitable type of shock absorber such as an air shock, MacPherson strut etc. The strut  206  tends to resiliently suspend the seat module  204  relative to the vessel, in that the strut  206  tends to cause the seat module  204  to remain in an upper at-rest position and to return to the at-rest position on cessation of a force causing the seat module  204  to move generally vertically towards a bottom position. 
     The support assembly  208  is interconnected between the deck mount  220  and the helm/control module  232 . The support assembly  208  comprises a spar assembly  250 , a simple pivot connector  252  at one end of the spar assembly  250 , and a fore-and-aft movement connector  254  at the other end of the spar assembly  250 . In the embodiments shown in the drawings and described herein, the simple pivot connector  252  connects the spar assembly  250  to the deck mount  220  and the fore-and-aft movement connector  254  connects the spar assembly  250  to the helm/control module  232 . However, it wilt be apparent that similar results could be achieved with a pivot connection between the spar assembly  250  and the helm/control module  232 , and a connection permitting fore-and-aft movement between the spar assembly  250  and the deck mount  220 . 
     In one embodiment, the spar assembly  250  includes two spars  260 , (preferably having heim joints  262 , also referred to as rod end bearings and rose joints, at each end). The spars  260  are oriented such that the ends of the spars  260  at the deck mount  220  are spaced wider apart than the ends of the spars  260  at the helm/control module  232 . 
     In another embodiment, the spar assembly  250  comprises a single spar member  264  configured such that simple pivot connection  252  at the deck mount  220  includes spaced-apart connection locations no as to provide resistance to athwart forces. 
     In one embodiment, the fore-and-aft movement connector  254  comprises a sliding assembly  270 , comprising a track assembly  272  slidably engaged with a car assembly  274 . The track assembly  272  comprises two parallel anodized aluminum rails. In the drawings, the parallel anodized aluminum rails are shown bolted directly to the seat module  204 . Alternatively, for tighter tolerances, the parallel anodized aluminum rails may be bolted to an adapter plate machined flat. The car assembly  274  comprises anodized aluminum cars containing a tow friction plastic sliding element configured to slidably engage with the parallel anodized aluminum rails, the aluminum cars being bolted to a welded stainless steel bracket. The sliding assembly  270  permits linear movement (defined by the engagement of the track assembly  272  and car assembly  274 ), as between the helm/control module  232  and the adjacent end of the spar assembly  250 . 
     In another embodiment, the fore-and-aft movement connector  254  comprises a pivoting assembly  280 , comprising a pivot block  282  (preferably anodized aluminum), a pivot cavity  284  and a pivot pin assembly  286  (preferably comprising a stainless steel pivot axle, held in place with a large hex bolt, with plastic bushings on which to pivot). The pivoting assembly  280  permits arcuate movement (defined by the pivotal movement of the pivot block  282  relative to the pivot cavity  284 ), as between the helm/control module  232  and the adjacent end of the spar assembly  250 . 
     Embodiments of the support assembly  208  may also include a shock absorber  290  to reduce the cantilever forces transmitted from the seat module  204  to the main suspension module  202 , during use. The shock absorber  290  may be interconnected between the helm/control module  232  and the fore-and-aft movement connector  254  or may be interconnected between the spar assembly  270  and the deck mount. 
     A preferred embodiment of the general configuration shown in  FIG. 1 , that is, an embodiment having a support assembly  208  with two spars  260 , a sliding assembly  270  and a shock absorber  290 , has the following features. A typical seat module  204  of the preferred embodiment projects about 4 feet from the main suspension module  202 , is about 2 feet wide, has a vertical dimension of about 3½ feet and weighs about 35 lbs. 
     The guide rail assembly  222  of the preferred embodiment is tilted aft 10 degrees from vertical (in this context, “vertical” assumes the vessel is at rest and at a desired trim). Each spar  260  has a mount center to mount center length of 22½ inches, and is made from 1¼ inch diameter swaged aluminum tube with a stainless steel rod end at each end. The two spars are positioned such that with the seat module  204  in the upper at-rest position, an imaginary plane defined by the two spars  260  is tilted forward 52 degrees from vertical; and with the seat module  204  in the bottom position, the imaginary plane defined by the two spars  260  is tilted forward 88 degrees from vertical. 
     In the preferred embodiment, the strut  206  preferably has a travel of about 12 inches. It has been found that a suitable strut  206 , is the Fox Racing Shocks, Fox Float 12″ (Part #: 939-99-007). A suitable operating pressure for the Fox Float 12″ has been found to be 65 psi, but this may be adjusted up or down by the user depending on ride conditions and the weight of the occupant/payload, In the preferred embodiment, the shock absorber  290  has a travel of about 2½ inches. It has been found that a suitable shock absorber  290  is the Fox Racing Shocks, Fox Float CTD 8.50″×2.50″ (Part #: 972-01-230). A suitable operating pressure for the Fox Float CTD 8.50″×2.50″ has been found to be 150 psi. 
     To be clear, as indicated above, it has been found that tilting the guide rail assembly  222  aft 10 degrees from vertical, provides desirable performance with respect to the combination of pitch and deceleration experienced in a wide range of operating conditions. However, a user may find a different angle may be better suited for a particular vessel or particular prevailing operating conditions. The main suspension module  202  may be configured to permit adjustment of the tilt of guide rail assembly  222 . Further, the guide rail assembly  222  described herein is configured to restrict seat module  204  to a defined linear reciprocating path. It has been found that restricting the seat module  204  to a defined linear reciprocating path provides desirable performance with respect to the combination of pitch and deceleration experienced in a wide range of operating conditions. However, the guide rail assembly  222  could be configured to restrict the seat module  204  to a defined non-linear reciprocating path, that is, a simple or complex curve, if this were found to be better suited for a particular vessel or particular prevailing operating conditions. 
     The scope of the claims should not be limited by the preferred embodiments set forth in the examples, but should be given the broadest interpretation consistent with the description as a whole.