US3298344A - Automatic trim correction - Google Patents
Automatic trim correction Download PDFInfo
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- US3298344A US3298344A US488705A US48870565A US3298344A US 3298344 A US3298344 A US 3298344A US 488705 A US488705 A US 488705A US 48870565 A US48870565 A US 48870565A US 3298344 A US3298344 A US 3298344A
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- boat
- panel
- water reaction
- leading
- expansible chamber
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
- B63B—SHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING
- B63B39/00—Equipment to decrease pitch, roll, or like unwanted vessel movements; Apparatus for indicating vessel attitude
- B63B39/06—Equipment to decrease pitch, roll, or like unwanted vessel movements; Apparatus for indicating vessel attitude to decrease vessel movements by using foils acting on ambient water
- B63B39/061—Equipment to decrease pitch, roll, or like unwanted vessel movements; Apparatus for indicating vessel attitude to decrease vessel movements by using foils acting on ambient water by using trimflaps, i.e. flaps mounted on the rear of a boat, e.g. speed boat
Definitions
- the present invention relates to trim correcting apparatus for boats, and more particularly to such an apparatus including panel means for changing trim by water reaction, and means for automatically sensing a condition of improper fore and aft or lateral trim and then causing operation of said panel means, for automatically correcting the trim.
- trim correcting means comprising a pair of generally horizontal water reaction panels, one on each side of the center line of the boat. Each panel is hinged along its forward edge to the boat substantially at the level of the undersurface of the boat. Means are provided for pivotally moving each panel about its hinge means, from a retracted inactive position downwardly to an active position, wherein it slopes downwardly and rearwardly from the undersurface of the boats bottom.
- a principal object of the present invention is to provide a trim correcting system of the same general type as those disclosed by the above-mentioned patents, but in which a novel fluid pressure actuated expansible chamber means is used for moving each water reaction panel downwardly from its inactive position to its active position, and further including a unique apparatus for automatically sensing a condition of improper fore and aft or lateral trim, and then in response to the signal received, controlling the supply of fluid to and from the expansible chamber means, for causing changes in the position of the water reaction panels.
- the fluid supply system comprises a source of fluid under pressure; supply conduit means leading from such source to each expansible chamber means, and including a separate inlet conduit leading into each expansible chamber means; and a normally closed solenoid valve in each inlet conduit.
- the automatic control means comprises electrical control circuitry including mercury switch means operable in response to boat roll or list beyond a predetermined position of lateral tilt to open only the solenoid valve in the inlet conduit leading to the expansible chamber means on the low side of the boat, and mercury switch means operable in response to bow rise beyond a predetermined position to open the solenoid valve in both inlet conduits.
- the expansible chamber means comprises a hermetically sealed inflatable tube member interposed between the water reaction panel, and a fixed support therefor spaced above the water reaction panel.
- inflatable tube means includes a pair of upwardly extending stems, one being an inlet stem and the other being an outlet stem, The stems project upwardly through openings therefor in the fixed support shelf, and supply and exhaust tube means, respectively, are connected to the stems above the shelf.
- the tube means leading to the inlet stem is a part of supply conduit means leading from a source of compressed air.
- the tube means connected 3,298,344 Patented Jan. 17, 1967 to the outlet stem is a part of an exhaust conduit means which leads to the atmosphere.
- Another object of the present invention is to provide a trim correctin device composed of a rigid bracket having an upstanding front wall by which it is mounted onto the lower portion of the transom of a boat, and a fixed shelf integral therewith, extending rearwardly from the lower portion of said front wall; and a reactance member secured to the transom below said bracket, with both the bracket and the reactance member being constructed from a glass fiber reinforced synthetic resin.
- the lower portion of the front wall of the bracket is offset rearwardly from the upper portion of such bracket, and the reactance member includes an upstanding front wall, the upper portion of which is positionable between t the transom and the lower portion of the front wall of the bracket, and is securable to the transom in a position of coplanar parallelism with the upper portion of the front wall of said bracket.
- the inflatable tube means which is constructed from rubber or a rubberlike material, is bounded at the top by the shelf, at the bottom by the water reaction panel, at its front by the front wall of the reactance member, and at its rear by the upstanding rear wall of the reactance member.
- a further object of the present invention is to provide a trim correcting device of the character described wherein the principal components are made from non-corrosive materials, and wherein such components are interrelated and arranged in such a manner that the metallic fastener and/or coupler elements used with such device do not contact and are not situated in close proximity to a metal part, resulting in galvanic corrosion being no problem.
- FIG. 1 is a perspective view taken from above and looking generally to the rear of a boat equipped with a pair of trim correcting devices typifying the present invention
- FIG. 2 is a fore and aft sectional view, on an enlarged scale, taken through an intermediate portion of one of the trim correcting devices, including a solid line showing of the reactance member and the inflatable tube member in inactive positions, and a broken line showing of such members in active positions, wherein the inflatable tube member is inflated and the water reaction panel of the reactance member slopes downwardly and rearwardly from the bottom of the boat;
- FIG. 3 is an exploded perspective view of one of the trim correctin devices, with the central rearward portion of the rigid shelf portion of its mounting bracket being cut away for clarity of illustration of the stem portions of the inflatable tube member;
- FIG. 4 is a schematic view of the fluid supply system and an electrical control means therefor, typifying an aspect of the invention, such view showing the position taken by the mercury in the switch capsules of mercury switch means when the boat is listing to the port side an amount greater than the angle of inclination of the laterally directed switch capsules, and showing the valve in the inlet line leading to the trim correcting device on the low
- FIG. 5 is a diagrammatic top plan view of a typical grouping of mercury switch capsules, involving two pairs of fore and aft directed capsules and two pairs of laterally directed capsules, and related to a top plan outline of the boat;
- FIG. 6 is a diagrammatic view taken substantially along line 66 of FIG. 5, and showing a related pair of the laterally directed mercury switch capsules mounted on inclined positions on a support table, the angle of inclination equaling a selected maximum permissible angle of lateral tilt, with the contacts being situated at the upper end of the capsules, and with the support table being level; and
- FIG. 7 is a view like FIG. 6, but showing the support table and the mercury capsules thereon tilted in the position they occupy when the boat is listed to the port side.
- a pair of trim correction devices 10, constructed according to the present invention are shown attached to the lower portion of the transom T of boat B, in symmetrical relationship on opposite sides of the boats keel K.
- Each trim correction device 10 is shown to comprise a rigid mounting bracket 12 having an upstanding mounting wall 14 and a rearwardly extending, generally horizontal shelf 16. Triangular brace members 18, or the like, extending between the mounting wall 14 and the shelf 16, give rigidity to the mounting bracket 12.
- a plurality of openings may be provided in the mounting wall 14, for receiving bolts 22, or the like, used for securing the bracket 12 to the transom T.
- a reactance member 23 is mounted on the transom T below bracket 12.
- the lower part of the brackets mounting wall 14 is preferably offset rearwardly of the upper portion, so as to provide space between it and the transom T, in which space the upper portion of the forward wall 24 of the reactance member 23 may be situated, substantially in coplanar parallelism with the upper portion of wall 14 (FIG. 2).
- a plurality of openings 26 are provided in the upper portion of wall 24, and are appropriately located so that they are registerable with the openings 20 in the lower part of wall 14.
- some of the fastening bolts 22 may extend through both an opening 29 in wall 14 and an opening 26 in wall 24, and serve to secure bot-h the mounting bracket 12 and the reactance member 23 to the transom T.
- Additional openings 28 may be provided in the lower part of wall 24 for the reception therein of screws 30, or the like.
- the reactance member 23 comprises a narrow support strip 32 forming a near rightangle corner with wall 24, a generally horizontal water reaction panel 34, a hinge 36 interconnecting the water reaction panel 34 with the support strip 32, and a rear flange 38 upstanding from the rear edge of panel 34 and terminating substantially at the level of, or somewhat above, shelf 16.
- the hinge 36 is located substantially at the level of the undersurface of the bottom 40 of boat B.
- the trim correction device 10 is positioned on the transom T with the water reaction panel 34 substantially at the level of the undersurface of the bottom 40.
- both bracket 12 and reactance member 23 are constructed from a glass fiber reinforced synthetic resin, (i.e. fiber glass) a typical resin being polymerizable unsaturated polyester, for example.
- the hinge 36 may merely be a reduced thickness portion of this material, as is illustrated.
- a hermetically sealed tube, bag or flexible walled container 42 of a resilient, rubber-like material is provided in the space defined on top of the shelves 16, on bottom by the water reaction panel 34, at front by the lower portion of wall 24, and the rear by the upstanding rear flange 38.
- rubber-like material means any material having the properties of the rubber used in inner tubes for pneumatic motor vehicle tires, and any equivalent materials capable of being inflated when formed into a closed container, and capable of substantially returning to its original shape when the inflating fluid pressure is released.
- the tube 42 is formed to include a pair of upstanding stems, designated 44 and 46, respectively, in FIG. 3. Each stem 44, 46 is similar to a valve stem for an inner tube, but does not include an internal valve device.
- a pair of openings 48, 50 are provided in the central portion of shelf 16.
- Stem 44 extends upwardly through opening 48, and stem 46 extends through opening 50.
- the stems 44, 48 may be externally threaded so that a retaining nut 47 may be screwed onto them from above the shelf 16.
- One of the stems 44, 46 is an inlet stem and the other is an outlet stem.
- stem 44 is the inlet and stem 46 is the outlet stem.
- a motive fluid inlet tub 52 forming a part of supply conduit means leading from a source of motive fluid, is attached to the portion of inlet stem 44 which stands up above shelf 16.
- an exhaust tube 54 forming a part of an exhaust conduit means, is attached to the portion of stem 46 which stands up above the shelf 16.
- tube members 52, 54 are shown in the form of flexible hoses, and conventional hose clamps 56 are used for securing them to the stems 44, 46, respectively.
- the nuts 47 may be dispensed with, and the hose clamps 56 many he used to secure the inflatable tube member 42 to the bracket 12.
- an off-on valve is provided in each supply conduit means, and another off-on valve means is provided in each exhaust conduit means.
- the tube 42 will be inflated to a size larger than the space for it between shelf 16 and water reaction panel 34. Since panel 16 is relatively rigid and substantially immovable, and since water reaction panel 34 is pivotally movable about the hinge 36, when the tube 42 is in flated, it forceably swings the panel 34 downwardly from a position substantially even with the undersurface of bottom 40 into a position wherein it slopes downwardly and re arwardly from the undersurface of the bottom.
- the supply conduit means of which the inlet tubes 52 are a part includes a stem line or conduit 53 leading from the source of motive fluid, a pressure regulator 60 in said main conduit 58, and branch conduits 62 leading from main conduit 58 to the inlet tubes 52.
- a normally closed off-0n solenoid valve V1 is situated between the branch conduit 62 and the inlet tube 52 for one of the devices 10, and a like normally closed off-0n solenoid valve V2 is interposed between the branch conduit 62 and the inlet tube 52 leading to the other device 10.
- compressed air is used as the motive fluid
- the source of motive fluid comprises a storage tank 64 fed by a compressor 66' driven by an electric motor 68.
- a check valve 70 is located in the inlet to the storage tank 64 from the compressor 66, and is adapted to permit compressed air to flow into but not out from the tank 64 through said inlet.
- the electrical circuitry for the electric motor 68 includes a source of direct current 72, a manually operated off-on switch 74, and a pressure responsive switch 76.
- the pressure responsive switch 76 senses the pressurein tank 64 and energizes the motor 68 whenever such pressure drops below a predetermined minimum valve.
- the tank 64 may also beused as a supply of compressed air for operating other auxiliaries aboard the boat, such as an air horn 7 8, for example.
- a normally closed oif-on solenoid valve V3 is provided in the exhaust conduit 54 leading from the trim correct ing device 10 with which valve V1 is associated, and a like normally closed off-on solenoid valve V4 is provided in the exhaust conduit 54 leading from the other trim correcting device 10.
- a trim condition sensing means is provided for sensing acondition of improper trim and then in response thereto controlling the valves V1, V2, V3, V4 in an appropriate manner to correct or at least improve the trim.
- the trim condition sensing mechanism may comprise four mercury switch assemblies, two of which, designated S1 and S2 are directed across or laterally of the boat, and the other two, designated S3, S4 are directed longitudinally of the boat, in the fore and aft direction.
- Each switch assembly may comprise a pair of switch capsules.
- The-capsules 8t], 82 of switch assembly S1, and the capsules 84, 86 as switch assembly S2, are each supported in an inclined position, with the rise being from their innermost to their outermost ends.
- the capsules 88, 90 of switch assembly S3, and the capsules 92, 94 of switch assembly S4, are also each supported in an inclined position. Capsules 88, 90 arise from their rear toward the front ends, and capsules 92, 94 rise from their front to their rear ends.
- a pair of contacts are located at the upper end of each of the switch capsules.
- the support table 96 to which the capsules are secured is level or inclined an amount less than the inclination of the switch capsules, the mercury gravitates to and stays at the lower ends of the capsules.
- the switch capsules may be of the type manufactured by the Micro Switch Division of Honeywell, of Freeport, Illinois, and identified as single-pole, single-throw switch, No. AS452 A1.
- the switch capsules may be supported in an inclined position by mounting them on the inclined surface of a triangular block that is in turn secured to the support table 96.
- Conventional mercury switch mounting clips may be secured to the inclined blocks so that the switch capsules may be easily installed and easily removed.
- the switch assemblies S1, S2 are shown to be inclined an amount equaling the selected maximum permissible amount of lateral tilt orlist of the boat.
- FIG. 7 when for some reason the boat lists to the port side an amount greater than the inclination of capsules 80, 82 relative to the uppersurface of table 96, the mercury gravitates to the ends of such capsules 80, 82 at which the contacts are located, bridges said contacts, and closes the circuit of which switch assembly S1 is a part.
- this causes energization and opening of solenoid vales V1, V4.
- the opening of valve V1 permits compressed air to flow from the tank 64 into the infilatable tube member 42 associated with the port side trim correction device 10.
- tube member 42 is inflated since valve V3 remains closed. As it increases in volume the tube 42 pushes the water reaction panel 34 of the port side device l downwardly into an active position in which it slopes downwardly and'rearwardly from the undersurface of the bottom 40. Water moving relatively across the lower surface of panel 34 is defected downwardly thereby, creating a lifting force by water reaction that tends to roll the boat back toward a level position. While this is happening the trim correcting device 10 on the starboard side of the boat is inactive because the valve V4 in exhaust conduit 64 is open.
- the switch assembly S2 becomes active to energize the solenoid valve means V2, V3 whenever the boat experiences a starboard list greater than the inclination of the switch capsules 84, 86.
- valves V3, V4 are a part, whereby such valves V3, V4 open and permit the escape of compressed air from both tubes 42.
- the water moving relatively across the lower surfaces of the water reaction panels 34 returns such panels 34 to their inactive positions at a slow rate determined by the rate of escape of the compressed air through the outlet stems 46 and the exhaust conduit means 54.
- the tubes 42 in effect function as dashpots or shock absorbers. Since the release of compressed air from the tube 42 is not sudden, but rather occurs relatively slowly over a period of time, thevmovement of the water reaction panels 34 is not sudden and jerky, but rather is slow, resulting in a smooth transition from one attitude of the boat to the next, by operation of the trim correcting devices 10.
- bracket 12 and reactance member 26 are both preferably constructed from a glass fiber reinforced synthetic resin, a typical example of the resin being polymerizable unsaturated polyester.
- the inflatable tube 42 is constructed from rubber or a rubher-like resilient material.
- the stems 44, 46 are constructed from or at least covered with rubber or a similar material.
- Tubes 52, 54 are preferably rub'ber, plastic, nylon or some other non-metalic material.
- the nuts or retaining elements 47, if used, may be made from nylon, plastic, or a similar material. All of the above-mentioned materials are noncorrosive. They will not corrode themselves and their use minimizes the corrosion of the metalic fastener elements 22, 30 and the metalic hose clamps 56.
- the solenoid valves V1, V2, V3, V4 are located inside of the 'boat, forwardly of the transom T.
- An opening is provided in the transom T for each of the tube members 52, 54.
- Each tube member 52, 54 may be continuous and extend through its opening in the transom.
- a through hull fitting of nylon for example, may be provided at each opening, and each tube 52, 54 may be made into sections a forward section interconnecting between one of the related solenoid controlled valves and the forward end of the fitting, and a rear-ward section interconnected between the rearward portion of the fitting and the portion of the related stem that projects above the support shelf 16.
- inlet and outlet manifolds may be provided, with each inlet tube member '52 leading from the inlet manifold, and each outlet'tube member 54 leading to the outlet manifold.
- the inlet manifold would then be connected to the air tank, and a outlet manifold would communicate with the atmosphere.
- the trim condition sensing mechanism may include eight switch assemblies, situated approximately forty-five degrees apart.
- a circular, single capsule mercury switch may be used, such capsule having one ball'of mercury and a plurality of pairs of contacts.
- a boat having a bottom; a pair of generally horizontal water reaction panels, one on each side of the center line of the boat, each water reaction panel being hinged along its forward edge to the boat substantially at the level of the undersurface of said bottom; a separate expansible chamber means for each water reaction panel, operable to swing the panel downwardly from an inactive position substantially even with or above the undersurface of said bottom to an active position wherein the panel slopes downwardly and rearwardly from the undersurface of said bottom; a source of fluid under pressure; supply conduit means leading from said source to each expansible chamber means, and including a separate conduit leading into each expansible chamber means; a normally closed solenoid valve in each inlet conduit; and electrical control means for said solenoid valves, including mercury switch means'operable in response to boat roll beyond a predetermined position of lateral tilt to open the solenoid valve in the inlet conduit leading to the expansible chamber means on the low side of the boat.
- said electrical control means further includes mercury switch means operable in response to bow rise beyond a predetermined position to open the solenoid valve in both inlet conduits.
- a boat having a bottom; a pair of I generally horizontal water reaction panels, one on each side of the center line of the boat, each water reaction stantially at the level of the undersurface of said bottom; a separate expansible chamber means for each water re-- action panel, operable to swing the panel downwardly from an inactive position substantially even with or above: the undersurface of said bottom to an active position. wherein the panel slopes downwardly and rearwardly' from the undersurface of said bottom; a source of fluid. under pressure; supply conduit means leading from said.
- each expansible chamber means including; a separate inlet conduit leading into each expansible chamber means; a normally closed solenoid valve in: each inlet conduit; an outlet conduit leading from each expansi-ble chamber means; a normally closed solenoid valve" in each outlet conduit; and electrical control means for said solenoid valves, including mercury switch means operable in response to boat roll beyond a predetermined position of lateral tilt to substantially simultaneously open the solenoid valve in the inlet conduit leading to the expansible chamber means on the low side of the boat, and the solenoid valve in the outlet conduit'leading from the expansible chamber means on the high side of the boat.
- said electrical control means further includes mercury switch means operable in response to bow rise beyond a predetermined position to open the solenoid valves in both inlet conduits, with the solenoid valves in the outlet conduit remaining closed.
- a boat having a bottom; a pair of generally horizontal water reaction panels, one on each. side of the center line of the boat, each water reaction panel being hinged along its forward edge to the boat sub-- stanti-ally at the level of the under'surface of said bottom; a separate expansible chamber means for each water reaction panel, operable to swing the panel downwardly from an inactive position substantially even with or above: the undersurface of said bottom to an active position wherein the panel slopes downwardly and rearwardly from the undersurface of said bottom; a source of fluid under pressure; supply conduit means leading from said source to each expansible chamber means, and including a separate inlet conduit leading into each expansible chamber means; a normally closed solenoid valve in each inlet conduit; and electrical control means for said solenoid valves, including mercury switch means operable in response to bow rise beyond a predetermined position to open the solenoid valves in both inlet conduits.
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Description
Jan. U, 1961 R. e. YUNKER ETAL 3,298,344
AUTOMATIC TRIM CORRECTION Filed Sept. 20. 1965,
2 Sheets-Sheet l Jan, 17, 1967 Filed Sept. 20, 19 5 3 as so R. E. YUNKER ETAL AUTOMATIC TRIM CORRECTION 2 Sheets-Sheet 2 I[ \"VEN1ORS ROBERT E. YUNKER BY JOHN P. SOUTHERN 62 FIG. 7
I HTTOR/I/FYS United States Patent 3,298,344 AUTOMATIC TRIM CORRECTHON Robert E. Yunker, 3635 Evanston N., Seattle, Wash. 98103, and John P. Southern, 910 Valley St., Seattle, Wash. 98109 Filed Sept. 20, 1965, Ser. No. 488,705 6 Claims. (Cl. 11466.5)
The present invention relates to trim correcting apparatus for boats, and more particularly to such an apparatus including panel means for changing trim by water reaction, and means for automatically sensing a condition of improper fore and aft or lateral trim and then causing operation of said panel means, for automatically correcting the trim.
In the operation of boats, it is highly desirable to be able to exercise some control over the fore and aft and lateral tilting movements of the boat during forward travel of the same. Various devices for controlling such tilting movements have been heretofore proposed, typical examples of which are disclosed by: Bennett, US. Patent No. 3,062,167; Jacobs et al. US. Patent No. 3,001,499;
Sherrill, US. Patent No. 3,046,928; Curtis, US. Patent- No. 3,058,442; Frederick, US. Patent No. 3,159,131; and Sherrill, US. Patent No. 3,177,837. Each of these patents discloses trim correcting means comprising a pair of generally horizontal water reaction panels, one on each side of the center line of the boat. Each panel is hinged along its forward edge to the boat substantially at the level of the undersurface of the boat. Means are provided for pivotally moving each panel about its hinge means, from a retracted inactive position downwardly to an active position, wherein it slopes downwardly and rearwardly from the undersurface of the boats bottom.
A principal object of the present invention is to provide a trim correcting system of the same general type as those disclosed by the above-mentioned patents, but in which a novel fluid pressure actuated expansible chamber means is used for moving each water reaction panel downwardly from its inactive position to its active position, and further including a unique apparatus for automatically sensing a condition of improper fore and aft or lateral trim, and then in response to the signal received, controlling the supply of fluid to and from the expansible chamber means, for causing changes in the position of the water reaction panels. Briefly, the fluid supply system comprises a source of fluid under pressure; supply conduit means leading from such source to each expansible chamber means, and including a separate inlet conduit leading into each expansible chamber means; and a normally closed solenoid valve in each inlet conduit. The automatic control means comprises electrical control circuitry including mercury switch means operable in response to boat roll or list beyond a predetermined position of lateral tilt to open only the solenoid valve in the inlet conduit leading to the expansible chamber means on the low side of the boat, and mercury switch means operable in response to bow rise beyond a predetermined position to open the solenoid valve in both inlet conduits.
In preferred form, the expansible chamber means comprises a hermetically sealed inflatable tube member interposed between the water reaction panel, and a fixed support therefor spaced above the water reaction panel. The
inflatable tube means includes a pair of upwardly extending stems, one being an inlet stem and the other being an outlet stem, The stems project upwardly through openings therefor in the fixed support shelf, and supply and exhaust tube means, respectively, are connected to the stems above the shelf. The tube means leading to the inlet stem is a part of supply conduit means leading from a source of compressed air. The tube means connected 3,298,344 Patented Jan. 17, 1967 to the outlet stem is a part of an exhaust conduit means which leads to the atmosphere.
Another object of the present invention is to provide a trim correctin device composed of a rigid bracket having an upstanding front wall by which it is mounted onto the lower portion of the transom of a boat, and a fixed shelf integral therewith, extending rearwardly from the lower portion of said front wall; and a reactance member secured to the transom below said bracket, with both the bracket and the reactance member being constructed from a glass fiber reinforced synthetic resin. In preferred form, the lower portion of the front wall of the bracket is offset rearwardly from the upper portion of such bracket, and the reactance member includes an upstanding front wall, the upper portion of which is positionable between t the transom and the lower portion of the front wall of the bracket, and is securable to the transom in a position of coplanar parallelism with the upper portion of the front wall of said bracket. cludes a relatively narrow support strip extending rear- Wardly in fixed position from the lower portion of the front wall of said reactance member; a relatively large water reactance panel of rectangular proportions disposed rearwardly of said support strip, and spaced below theshelf of said bracket; hinge'means pivotally connecting the water reaction panel to the support strip; and a rear wall or flange that extends upwardly from the rear edge of the water reaction panel. The inflatable tube means, which is constructed from rubber or a rubberlike material, is bounded at the top by the shelf, at the bottom by the water reaction panel, at its front by the front wall of the reactance member, and at its rear by the upstanding rear wall of the reactance member.
A further object of the present invention is to provide a trim correcting device of the character described wherein the principal components are made from non-corrosive materials, and wherein such components are interrelated and arranged in such a manner that the metallic fastener and/or coupler elements used with such device do not contact and are not situated in close proximity to a metal part, resulting in galvanic corrosion being no problem.
These and other objects, features, and advantages of the present invention will be apparent from the fol-lowing description, appended claims, and annexed drawings.
Referring to the drawings wherein like reference characters designate like parts throughout the several views:
FIG. 1 is a perspective view taken from above and looking generally to the rear of a boat equipped with a pair of trim correcting devices typifying the present invention;
FIG. 2 is a fore and aft sectional view, on an enlarged scale, taken through an intermediate portion of one of the trim correcting devices, including a solid line showing of the reactance member and the inflatable tube member in inactive positions, and a broken line showing of such members in active positions, wherein the inflatable tube member is inflated and the water reaction panel of the reactance member slopes downwardly and rearwardly from the bottom of the boat;
FIG. 3 is an exploded perspective view of one of the trim correctin devices, with the central rearward portion of the rigid shelf portion of its mounting bracket being cut away for clarity of illustration of the stem portions of the inflatable tube member;
FIG. 4 is a schematic view of the fluid supply system and an electrical control means therefor, typifying an aspect of the invention, such view showing the position taken by the mercury in the switch capsules of mercury switch means when the boat is listing to the port side an amount greater than the angle of inclination of the laterally directed switch capsules, and showing the valve in the inlet line leading to the trim correcting device on the low The reactance member also in- .1 =3) side of the boat, and the valve in the exhaust conduit means leading from the trim correcting device on the high side of the boat, both open;
FIG. 5 is a diagrammatic top plan view of a typical grouping of mercury switch capsules, involving two pairs of fore and aft directed capsules and two pairs of laterally directed capsules, and related to a top plan outline of the boat;
FIG. 6 is a diagrammatic view taken substantially along line 66 of FIG. 5, and showing a related pair of the laterally directed mercury switch capsules mounted on inclined positions on a support table, the angle of inclination equaling a selected maximum permissible angle of lateral tilt, with the contacts being situated at the upper end of the capsules, and with the support table being level; and
FIG. 7 is a view like FIG. 6, but showing the support table and the mercury capsules thereon tilted in the position they occupy when the boat is listed to the port side.
Referring more specifically to FIG. 1, a pair of trim correction devices 10, constructed according to the present invention, are shown attached to the lower portion of the transom T of boat B, in symmetrical relationship on opposite sides of the boats keel K.
Each trim correction device 10 is shown to comprise a rigid mounting bracket 12 having an upstanding mounting wall 14 and a rearwardly extending, generally horizontal shelf 16. Triangular brace members 18, or the like, extending between the mounting wall 14 and the shelf 16, give rigidity to the mounting bracket 12.
A plurality of openings, some of which are designated 20 in FIG. 3, may be provided in the mounting wall 14, for receiving bolts 22, or the like, used for securing the bracket 12 to the transom T. As clearly shown by FIG. 2, a reactance member 23 is mounted on the transom T below bracket 12. The lower part of the brackets mounting wall 14 is preferably offset rearwardly of the upper portion, so as to provide space between it and the transom T, in which space the upper portion of the forward wall 24 of the reactance member 23 may be situated, substantially in coplanar parallelism with the upper portion of wall 14 (FIG. 2).
A plurality of openings 26 are provided in the upper portion of wall 24, and are appropriately located so that they are registerable with the openings 20 in the lower part of wall 14. Thus, some of the fastening bolts 22 may extend through both an opening 29 in wall 14 and an opening 26 in wall 24, and serve to secure bot-h the mounting bracket 12 and the reactance member 23 to the transom T. Additional openings 28 may be provided in the lower part of wall 24 for the reception therein of screws 30, or the like.
In addition to front wall 24, the reactance member 23 comprises a narrow support strip 32 forming a near rightangle corner with wall 24, a generally horizontal water reaction panel 34, a hinge 36 interconnecting the water reaction panel 34 with the support strip 32, and a rear flange 38 upstanding from the rear edge of panel 34 and terminating substantially at the level of, or somewhat above, shelf 16. As shown by FIG. 2, the hinge 36 is located substantially at the level of the undersurface of the bottom 40 of boat B. Also, the trim correction device 10 is positioned on the transom T with the water reaction panel 34 substantially at the level of the undersurface of the bottom 40.
Preferably, both bracket 12 and reactance member 23 are constructed from a glass fiber reinforced synthetic resin, (i.e. fiber glass) a typical resin being polymerizable unsaturated polyester, for example. The hinge 36 may merely be a reduced thickness portion of this material, as is illustrated.
A hermetically sealed tube, bag or flexible walled container 42 of a resilient, rubber-like material is provided in the space defined on top of the shelves 16, on bottom by the water reaction panel 34, at front by the lower portion of wall 24, and the rear by the upstanding rear flange 38. As used herein, the term rubber-like material" means any material having the properties of the rubber used in inner tubes for pneumatic motor vehicle tires, and any equivalent materials capable of being inflated when formed into a closed container, and capable of substantially returning to its original shape when the inflating fluid pressure is released. Preferably, the tube 42 is formed to include a pair of upstanding stems, designated 44 and 46, respectively, in FIG. 3. Each stem 44, 46 is similar to a valve stem for an inner tube, but does not include an internal valve device.
A pair of openings 48, 50 are provided in the central portion of shelf 16. Stem 44 extends upwardly through opening 48, and stem 46 extends through opening 50. The stems 44, 48 may be externally threaded so that a retaining nut 47 may be screwed onto them from above the shelf 16. One of the stems 44, 46 is an inlet stem and the other is an outlet stem. In the illustrated embodiment, stem 44 is the inlet and stem 46 is the outlet stem.
A motive fluid inlet tub 52, forming a part of supply conduit means leading from a source of motive fluid, is attached to the portion of inlet stem 44 which stands up above shelf 16. In similar fashion, an exhaust tube 54, forming a part of an exhaust conduit means, is attached to the portion of stem 46 which stands up above the shelf 16. In the drawing, tube members 52, 54 are shown in the form of flexible hoses, and conventional hose clamps 56 are used for securing them to the stems 44, 46, respectively. In an arrangement such as this, the nuts 47 may be dispensed with, and the hose clamps 56 many he used to secure the inflatable tube member 42 to the bracket 12.
As will hereinafter be described in greater detail, an off-on valve is provided in each supply conduit means, and another off-on valve means is provided in each exhaust conduit means. As will be apparent, when motive fluid is supplied into the inflatable tube 42 through its inlet stem 44, and the valve in the exhaust conduit means is closed, the tube 42 will be inflated to a size larger than the space for it between shelf 16 and water reaction panel 34. Since panel 16 is relatively rigid and substantially immovable, and since water reaction panel 34 is pivotally movable about the hinge 36, when the tube 42 is in flated, it forceably swings the panel 34 downwardly from a position substantially even with the undersurface of bottom 40 into a position wherein it slopes downwardly and re arwardly from the undersurface of the bottom.
During boat travel the water that flows relatively across the undersurface of a water reaction panel 34 is deflected downwardly thereby, creating an upwardly directed force component by water reaction, tending to lift the trim correction device It and the part of the boat to which it is secured. The water also tends to push the panel 34 upwardly, but such movement is resisted by the fluid in tube 42. However, when the valve in the exhaust conduit means is opened, and the supply of motive fluid is stopped, the water force can and will return the water reaction panel 34 to a position substantially even with the undersurfaoe of bottom 40.
Referring now to FIGS. 4-7, the supply conduit means of which the inlet tubes 52 are a part includes a stem line or conduit 53 leading from the source of motive fluid, a pressure regulator 60 in said main conduit 58, and branch conduits 62 leading from main conduit 58 to the inlet tubes 52. A normally closed off-0n solenoid valve V1 is situated between the branch conduit 62 and the inlet tube 52 for one of the devices 10, and a like normally closed off-0n solenoid valve V2 is interposed between the branch conduit 62 and the inlet tube 52 leading to the other device 10.
Preferably, compressed air is used as the motive fluid, and the source of motive fluid comprises a storage tank 64 fed by a compressor 66' driven by an electric motor 68.
A check valve 70 is located in the inlet to the storage tank 64 from the compressor 66, and is adapted to permit compressed air to flow into but not out from the tank 64 through said inlet.
The electrical circuitry for the electric motor 68 includes a source of direct current 72, a manually operated off-on switch 74, and a pressure responsive switch 76. The pressure responsive switch 76 senses the pressurein tank 64 and energizes the motor 68 whenever such pressure drops below a predetermined minimum valve. The tank 64 may also beused as a supply of compressed air for operating other auxiliaries aboard the boat, such as an air horn 7 8, for example.
A normally closed oif-on solenoid valve V3 is provided in the exhaust conduit 54 leading from the trim correct ing device 10 with which valve V1 is associated, and a like normally closed off-on solenoid valve V4 is provided in the exhaust conduit 54 leading from the other trim correcting device 10.
According to one aspect of theinvention, a trim condition sensing means is provided for sensing acondition of improper trim and then in response thereto controlling the valves V1, V2, V3, V4 in an appropriate manner to correct or at least improve the trim.
By way of typical example, the trim condition sensing mechanism may comprise four mercury switch assemblies, two of which, designated S1 and S2 are directed across or laterally of the boat, and the other two, designated S3, S4 are directed longitudinally of the boat, in the fore and aft direction.
Each switch assembly may comprise a pair of switch capsules. The-capsules 8t], 82 of switch assembly S1, and the capsules 84, 86 as switch assembly S2, are each supported in an inclined position, with the rise being from their innermost to their outermost ends. The capsules 88, 90 of switch assembly S3, and the capsules 92, 94 of switch assembly S4, are also each supported in an inclined position. Capsules 88, 90 arise from their rear toward the front ends, and capsules 92, 94 rise from their front to their rear ends.
As clearly shown by FIG. 4, a pair of contacts are located at the upper end of each of the switch capsules. When the support table 96 to which the capsules are secured is level or inclined an amount less than the inclination of the switch capsules, the mercury gravitates to and stays at the lower ends of the capsules.
By way of typical and therefore non-limitive example, the switch capsules may be of the type manufactured by the Micro Switch Division of Honeywell, of Freeport, Illinois, and identified as single-pole, single-throw switch, No. AS452 A1.
The switch capsules may be supported in an inclined position by mounting them on the inclined surface of a triangular block that is in turn secured to the support table 96. Conventional mercury switch mounting clips may be secured to the inclined blocks so that the switch capsules may be easily installed and easily removed.
Referring to FIGS. 6 and 7, the switch assemblies S1, S2 are shown to be inclined an amount equaling the selected maximum permissible amount of lateral tilt orlist of the boat. As shown by FIG. 7, when for some reason the boat lists to the port side an amount greater than the inclination of capsules 80, 82 relative to the uppersurface of table 96, the mercury gravitates to the ends of such capsules 80, 82 at which the contacts are located, bridges said contacts, and closes the circuit of which switch assembly S1 is a part. As shown by FIG. 4, this causes energization and opening of solenoid vales V1, V4. The opening of valve V1 permits compressed air to flow from the tank 64 into the infilatable tube member 42 associated with the port side trim correction device 10. As will be apparent, such tube member 42 is inflated since valve V3 remains closed. As it increases in volume the tube 42 pushes the water reaction panel 34 of the port side device l downwardly into an active position in which it slopes downwardly and'rearwardly from the undersurface of the bottom 40. Water moving relatively across the lower surface of panel 34 is defected downwardly thereby, creating a lifting force by water reaction that tends to roll the boat back toward a level position. While this is happening the trim correcting device 10 on the starboard side of the boat is inactive because the valve V4 in exhaust conduit 64 is open.
As will be apparent from an inspection of FIG. '4, the switch assembly S2 becomes active to energize the solenoid valve means V2, V3 whenever the boat experiences a starboard list greater than the inclination of the switch capsules 84, 86.
Whenever the bow of the boat rises in the water an amount greater than a predetermined maximum, determined by the inclination of switch capsules 92, 94, the mercury in switch capsules 92, 94 will gratitate to the rear ends of such capsules and bridge the contacts thereat. The circuitry of which solenoid valve means V1, V2 are a part is closed, and such valves V1, V2 open, While valves V3, V4 remain closed. Compressed air rushes into the inflatable tube member 42 of both devices 10,
moving both water reaction panels 34 downwardly into an operative or active position. Substantially the same amount of lift is produced at each side of the stern of the boat, and such lift causes the stem to rise and the bow to drop.
Whenever the bow drops below a predetermined position, determinedby the inclination of switch capsules 88, 90, the mercury will gravitate 'to the forward ends of such capsules 88, and bridge the contacts thereat. As will be evident, by the time this happens the mercury in capsules 92, 94 will have gravitated back to the lower endsof such capsules, causing a break in the circuit of which solenoid valves V1, V2 are a part, and as a result the solenoid valves V1, V2 will be closed.
The closing of switches 88, 90 completes the circuit of which valves V3, V4 are a part, whereby such valves V3, V4 open and permit the escape of compressed air from both tubes 42. The water moving relatively across the lower surfaces of the water reaction panels 34 returns such panels 34 to their inactive positions at a slow rate determined by the rate of escape of the compressed air through the outlet stems 46 and the exhaust conduit means 54.
As will readily be apparent, during the exhausting procedure the tubes 42 in effect function as dashpots or shock absorbers. Since the release of compressed air from the tube 42 is not sudden, but rather occurs relatively slowly over a period of time, thevmovement of the water reaction panels 34 is not sudden and jerky, but rather is slow, resulting in a smooth transition from one attitude of the boat to the next, by operation of the trim correcting devices 10.
As previously mentioned, bracket 12 and reactance member 26 are both preferably constructed from a glass fiber reinforced synthetic resin, a typical example of the resin being polymerizable unsaturated polyester. The inflatable tube 42 is constructed from rubber or a rubher-like resilient material. The stems 44, 46 are constructed from or at least covered with rubber or a similar material. Tubes 52, 54 are preferably rub'ber, plastic, nylon or some other non-metalic material. The nuts or retaining elements 47, if used, may be made from nylon, plastic, or a similar material. All of the above-mentioned materials are noncorrosive. They will not corrode themselves and their use minimizes the corrosion of the metalic fastener elements 22, 30 and the metalic hose clamps 56. These components 22, 30, 56 are subject to oxidation because they are made of metal, but they do not contact and are situated in close proximity to another metallic part. Consequently, the conditions necessary for the occurrence of galvanic corrosion are not present, and essentially no galvanic corrosion occurs. This is a very important feature of the present invention 'because galvanic corrosion is a much more destructive than simple oxidation.
The solenoid valves V1, V2, V3, V4 are located inside of the 'boat, forwardly of the transom T. An opening is provided in the transom T for each of the tube members 52, 54. Each tube member 52, 54 may be continuous and extend through its opening in the transom. Alternatively, a through hull fitting of nylon, for example, may be provided at each opening, and each tube 52, 54 may be made into sections a forward section interconnecting between one of the related solenoid controlled valves and the forward end of the fitting, and a rear-ward section interconnected between the rearward portion of the fitting and the portion of the related stem that projects above the support shelf 16.
In relatively large boats it may be necessary to install two, or maybe three trim correcting devices 10 on each side of the keel K. In such an arrangement inlet and outlet manifolds may be provided, with each inlet tube member '52 leading from the inlet manifold, and each outlet'tube member 54 leading to the outlet manifold. The inlet manifold would then be connected to the air tank, and a outlet manifold would communicate with the atmosphere. 7
Having thus described the invention, it is clear that the objects as stated above have been attained in a simple and practical manner. While a particular embodiment of the inventionhas been shown and described, it is to be understood that changes may be made in the construction andarrangement of the various parts without de panel being hinged along its forward edge to the boat sub-- parting from the sphere and scope of the invention as expressed in the following claims. For example, more than four switch assemblies may be employed. The trim condition sensing mechanism may include eight switch assemblies, situated approximately forty-five degrees apart. Or a circular, single capsule mercury switch may be used, such capsule having one ball'of mercury and a plurality of pairs of contacts.
What is claimed is:
1. In combination, a boat having a bottom; a pair of generally horizontal water reaction panels, one on each side of the center line of the boat, each water reaction panel being hinged along its forward edge to the boat substantially at the level of the undersurface of said bottom; a separate expansible chamber means for each water reaction panel, operable to swing the panel downwardly from an inactive position substantially even with or above the undersurface of said bottom to an active position wherein the panel slopes downwardly and rearwardly from the undersurface of said bottom; a source of fluid under pressure; supply conduit means leading from said source to each expansible chamber means, and including a separate conduit leading into each expansible chamber means; a normally closed solenoid valve in each inlet conduit; and electrical control means for said solenoid valves, including mercury switch means'operable in response to boat roll beyond a predetermined position of lateral tilt to open the solenoid valve in the inlet conduit leading to the expansible chamber means on the low side of the boat.
2. The combination of claim 1, wherein said electrical control means further includes mercury switch means operable in response to bow rise beyond a predetermined position to open the solenoid valve in both inlet conduits.
3. In combination, a boat having a bottom; a pair of I generally horizontal water reaction panels, one on each side of the center line of the boat, each water reaction stantially at the level of the undersurface of said bottom; a separate expansible chamber means for each water re-- action panel, operable to swing the panel downwardly from an inactive position substantially even with or above: the undersurface of said bottom to an active position. wherein the panel slopes downwardly and rearwardly' from the undersurface of said bottom; a source of fluid. under pressure; supply conduit means leading from said. source to each expansible chamber means, and including; a separate inlet conduit leading into each expansible chamber means; a normally closed solenoid valve in: each inlet conduit; an outlet conduit leading from each expansi-ble chamber means; a normally closed solenoid valve" in each outlet conduit; and electrical control means for said solenoid valves, including mercury switch means operable in response to boat roll beyond a predetermined position of lateral tilt to substantially simultaneously open the solenoid valve in the inlet conduit leading to the expansible chamber means on the low side of the boat, and the solenoid valve in the outlet conduit'leading from the expansible chamber means on the high side of the boat.
4. The combination of claim 3, wherein said electrical control means further includes mercury switch means operable in response to bow rise beyond a predetermined position to open the solenoid valves in both inlet conduits, with the solenoid valves in the outlet conduit remaining closed.
5. In combination, a boat having a bottom; a pair of generally horizontal water reaction panels, one on each. side of the center line of the boat, each water reaction panel being hinged along its forward edge to the boat sub-- stanti-ally at the level of the under'surface of said bottom; a separate expansible chamber means for each water reaction panel, operable to swing the panel downwardly from an inactive position substantially even with or above: the undersurface of said bottom to an active position wherein the panel slopes downwardly and rearwardly from the undersurface of said bottom; a source of fluid under pressure; supply conduit means leading from said source to each expansible chamber means, and including a separate inlet conduit leading into each expansible chamber means; a normally closed solenoid valve in each inlet conduit; and electrical control means for said solenoid valves, including mercury switch means operable in response to bow rise beyond a predetermined position to open the solenoid valves in both inlet conduits.
6. The combination of claim 5, further including an outlet conduit leading from each expansible' chamber means, and a normally closed solenoid valve in each outlet conduit, and wherein said electrical control means further includes mercury switch means operable in response to lowering of the bow below said predetermined position to close the solenoid valves in the inlet conduits and to open the solenoid valves in both outlet conduits.
References Cited by the Examiner UNITED STATES PATENTS 2,265,206 12/1941 Stampfl ll4--66.5 3,001,499 9/1961 Jacobs et a1. 11466.5 3,002,485 10/1961 Curtis 114-665 3,026,839 3/1962 Fridge ll4-66.S
MILTON BUCHLER, Primary Examiner.
ANDREW H. FARRELL, Examiner.
Claims (1)
1. IN COMBINATION, A BOAT HAVING A BOTTOM; A PAIR OF GENERALLY HORIZONTAL WATER REACTION PANELS, ONE ON EACH SIDE OF THE CENTER LINE OF THE BOAT, EACH WATER REACTION PANEL BEING HINGED ALONG ITS FORWARD EDGE TO THE BOAT SUBSTANTIALLY AT THE LEVEL OF THE UNDERSURFACE OF SAID BOTTOM; A SEPARATE EXPANSIBLE CHAMBER MEANS FOR EACH WATER REACTION PANEL, OPERABLE TO SWING THE PANEL DOWNWARDLY FROM AN INACTIVE POSITION SUBSTANTIALLY EVEN WITH OR ABOVE THE UNDERSURFACE OF SAID BOTTOM TO AN ACTIVE POSITION WHEREIN THE PANEL SLOPES DOWNWARDLY AND REARWARDLY FROM THE UNDERSURFACE OF SAID BOTTOM; A SOURCE OF FLUID UNDER PRESSURE; SUPPLY CONDUIT MEANS LEADING FROM SAID SOURCE TO EACH EXPANSIBLE CHAMBER MEANS, AND INCLUDING A SEPARATE CONDUIT LEADING INTO EACH EXPANSIBLE CHAMBER MEANS; A NORMALLY CLOSED SOLENOID VALVE IN EACH INLET CONDUIT; AND ELECTRICAL CONTROL MEANS FOR SAID SOLENOID VALVES, INCLUDING MERCURY SWITCH MEANS OPERABLE IN RESPONSE TO BOAT ROLL BEYOND A PREDETERMINED POSITION OF LATERAL TILT TO OPEN THE SOLENOID VALVE IN THE INLET CONDUIT LEADING TO THE EXPANSIBLE CHAMBER MEANS ON THE LOW SIDE OF THE BOAT.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US488705A US3298344A (en) | 1965-09-20 | 1965-09-20 | Automatic trim correction |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US488705A US3298344A (en) | 1965-09-20 | 1965-09-20 | Automatic trim correction |
Publications (1)
Publication Number | Publication Date |
---|---|
US3298344A true US3298344A (en) | 1967-01-17 |
Family
ID=23940778
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US488705A Expired - Lifetime US3298344A (en) | 1965-09-20 | 1965-09-20 | Automatic trim correction |
Country Status (1)
Country | Link |
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US (1) | US3298344A (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3814044A (en) * | 1972-11-07 | 1974-06-04 | F Kercheval | Boat leveler tab |
US3977349A (en) * | 1974-11-27 | 1976-08-31 | Max Hummel | Boat positioning device |
US5263432A (en) * | 1991-08-20 | 1993-11-23 | Davis Dale R | Automatic trim tab control for power boats |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2265206A (en) * | 1939-09-13 | 1941-12-09 | Walter J Stampfi | Hydroplane boat |
US3001499A (en) * | 1959-03-16 | 1961-09-26 | Marcellus L Jacobs | Rear mounted planing and stabilizing structure for power boats |
US3002485A (en) * | 1960-07-22 | 1961-10-03 | Gerald J Curtis | Adjustable stabilizer for boats |
US3026839A (en) * | 1960-08-22 | 1962-03-27 | Clifford V Fridge | Boats |
-
1965
- 1965-09-20 US US488705A patent/US3298344A/en not_active Expired - Lifetime
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2265206A (en) * | 1939-09-13 | 1941-12-09 | Walter J Stampfi | Hydroplane boat |
US3001499A (en) * | 1959-03-16 | 1961-09-26 | Marcellus L Jacobs | Rear mounted planing and stabilizing structure for power boats |
US3002485A (en) * | 1960-07-22 | 1961-10-03 | Gerald J Curtis | Adjustable stabilizer for boats |
US3026839A (en) * | 1960-08-22 | 1962-03-27 | Clifford V Fridge | Boats |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3814044A (en) * | 1972-11-07 | 1974-06-04 | F Kercheval | Boat leveler tab |
US3977349A (en) * | 1974-11-27 | 1976-08-31 | Max Hummel | Boat positioning device |
US5263432A (en) * | 1991-08-20 | 1993-11-23 | Davis Dale R | Automatic trim tab control for power boats |
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