RETRACTABLE PIER
United States Patent 3747354
A portable pier or landing dock is provided for use, for example at small lakes and private cottages, comprising a pair of pier members hingedly affixed to each other with the end of one pier member hingedly mounted with respect to ground. A cable is connected to the distal end of the latter hinged pier member and operated by winding on a winch mounted on a dead anchor mounted in the ground. In a preferred embodiment an adjustable leg is provided at the distal end of the second pier member having a water buoyant floatable roller at the end thereof. Additionally, in an improved embodiment, a thrust rod is provided pivotally mounted at one end at a point fixed with respect to the ground near the pivotal point of the first pier member, and pivotally connected at the other end to a point on the second pier member spaced outwardly from its hinged joint with the first pier member to form a suitable geometric pattern for facilitating the extension and launching of the second pier member.
US Patent References:
Portable sectional pier
Karst - August 1960 - 2948121
Bridge and mobile launching structure therefor
Frost - June 1951 - 2556175
Portable dock
Gillman et al. - April 1968 - 3380257
Roll out-roll in dock
Eisert et al. - August 1968 - 3397546
Portable landing dock
Holsten - November 1952 - 2618124
Portable sectional pier
Karst - August 1960 - 2948121
Bridge and mobile launching structure therefor
Frost - June 1951 - 2556175
Portable dock
Gillman et al. - April 1968 - 3380257
Roll out-roll in dock
Eisert et al. - August 1968 - 3397546
Portable landing dock
Holsten - November 1952 - 2618124
Application Number:
05/153555
Publication Date:
07/24/1973
Filing Date:
06/16/1971
View Patent Images:
Export Citation:
Assignee:
Torrey, Edwin A. (Albion, MI)
Primary Class:
Other Classes:
14/71.100, 14/69.500
International Classes:
E01D15/24; E02B3/06; E01D15/00; E02B3/20
Field of Search:
61/48,49 14/31,36,37,42,71,1
US Patent References:
Primary Examiner:
Stein, Mervin
Assistant Examiner:
Kannan, Philip C.
Claims:
I therefore particularly point out and distinctly claim as my invention
1. A pier structure adapted to be mounted on a shore bounding a body of water and when so mounted to be extendable to normal operating position over said body of water and retractable from said body of water for storage, said pier structure comprising first and second pier members each formed of a longitudinal frame and a floor mounted thereon, the proximal end of said first pier member being adapted to be pivotally mounted with respect to said shore, hinge means connecting the distal end of said first pier member with the proximal end of said second pier member in relationship to permit said second pier member to retract downwardly when the hinged ends of said pier members are raised, means for limiting the relative angular position of said pier members to substantially a straight line in the extended and operating position, an adjustable leg affixed at the distal end of said second pier member having a roller rotatably mounted at the end thereof and adapted to roll on the bottom of said body of water when said pier structure is in extended operating position, a flexible line having one end affixed to one of said pier members at said hinge means joining them; means adapted to be mounted in fixed relationship to said shore and adapted to retrieve or to pay out said flexible line, thereby raising said pier members into storage position or causing said pier members to extend into normal operating position, and said pier structure additionally having a truss rod with one and pivotally mounted in fixed position with respect to the shore and the other end being pivotally so connected to said second pier member that when said line is permitted to extend and to lower said pier members, the distal end of said second pier member is caused by said truss rod to extend in a forward direction.
2. A pier structure according to claim 1, wherein said longitudinal frame comprises side rails having said floor mounted thereon.
3. A pier structure according to claim 1, wherein said proximal end of said first pier member is pivotally mounted by means of a pair of plates fixed with respect to the ground and having bearings mounted thereon, and a shaft mounted on said first pier member and journaled through said bearings.
4. A pier structure according to claim 1, wherein said adjustable leg comprises a pair of telescoping members, one of which is affixed to said second pier member and the other of which is provided with a U-shaped trunnion structure having a shaft engaged by the ends of said trunnion structure with said roller rotatably mounted on said shaft.
5. A pier structure according to claim 4, wherein said roller is water-buoyant.
6. A pier structure according to claim 4, wherein said roller is formed of sheet metal having a foamed plastic material therein.
7. A pier structure according to claim 1, wherein said flexible line is wire cable.
8. A pier structure according to claim 1, wherein means adapted to retrieve said line comprises a post fixed with respect to the shore having a winch mounted thereon engaging said line.
9. A pier structure according to claim 8, wherein said post comprises a pair of telescoping members, one of which is embedded in a concrete structure and the other of which is slidably engageable in said first telescoping member and has said winch mounted thereon, and means for affixing said telescoping members together.
10. A pier structure according to claim 1, wherein said truss rod comprises a pair of telescoping members, the inner one of said members having means affixed thereto limiting the distance by which said inner rod can telescope into said outer rod.
11. A pier structure according to claim 10, wherein said roller is spool-formed, having a pair of radial flanges and a central portion of reduced diameter, thereby permitting said truss rod to recess therein when said pier structure is in the fully retracted position.
1. A pier structure adapted to be mounted on a shore bounding a body of water and when so mounted to be extendable to normal operating position over said body of water and retractable from said body of water for storage, said pier structure comprising first and second pier members each formed of a longitudinal frame and a floor mounted thereon, the proximal end of said first pier member being adapted to be pivotally mounted with respect to said shore, hinge means connecting the distal end of said first pier member with the proximal end of said second pier member in relationship to permit said second pier member to retract downwardly when the hinged ends of said pier members are raised, means for limiting the relative angular position of said pier members to substantially a straight line in the extended and operating position, an adjustable leg affixed at the distal end of said second pier member having a roller rotatably mounted at the end thereof and adapted to roll on the bottom of said body of water when said pier structure is in extended operating position, a flexible line having one end affixed to one of said pier members at said hinge means joining them; means adapted to be mounted in fixed relationship to said shore and adapted to retrieve or to pay out said flexible line, thereby raising said pier members into storage position or causing said pier members to extend into normal operating position, and said pier structure additionally having a truss rod with one and pivotally mounted in fixed position with respect to the shore and the other end being pivotally so connected to said second pier member that when said line is permitted to extend and to lower said pier members, the distal end of said second pier member is caused by said truss rod to extend in a forward direction.
2. A pier structure according to claim 1, wherein said longitudinal frame comprises side rails having said floor mounted thereon.
3. A pier structure according to claim 1, wherein said proximal end of said first pier member is pivotally mounted by means of a pair of plates fixed with respect to the ground and having bearings mounted thereon, and a shaft mounted on said first pier member and journaled through said bearings.
4. A pier structure according to claim 1, wherein said adjustable leg comprises a pair of telescoping members, one of which is affixed to said second pier member and the other of which is provided with a U-shaped trunnion structure having a shaft engaged by the ends of said trunnion structure with said roller rotatably mounted on said shaft.
5. A pier structure according to claim 4, wherein said roller is water-buoyant.
6. A pier structure according to claim 4, wherein said roller is formed of sheet metal having a foamed plastic material therein.
7. A pier structure according to claim 1, wherein said flexible line is wire cable.
8. A pier structure according to claim 1, wherein means adapted to retrieve said line comprises a post fixed with respect to the shore having a winch mounted thereon engaging said line.
9. A pier structure according to claim 8, wherein said post comprises a pair of telescoping members, one of which is embedded in a concrete structure and the other of which is slidably engageable in said first telescoping member and has said winch mounted thereon, and means for affixing said telescoping members together.
10. A pier structure according to claim 1, wherein said truss rod comprises a pair of telescoping members, the inner one of said members having means affixed thereto limiting the distance by which said inner rod can telescope into said outer rod.
11. A pier structure according to claim 10, wherein said roller is spool-formed, having a pair of radial flanges and a central portion of reduced diameter, thereby permitting said truss rod to recess therein when said pier structure is in the fully retracted position.
Description:
BACKGROUND OF THE INVENTION
The present invention relates to piers and landing docks for use at lakes or rivers for providing access to and docking facilities for small boats, and more particularly is concerned with a pier of the type described which may be readily raised out of the water for storage during periods of nonuse.
Piers and landing docks used at lake resorts, homes at private lakes, or other places where boats are generally moored are subject to considerable damage and destruction during the winter months when ice forms across the lake. The danger of damage and destruction is particularly severe when the ice breaks up in the spring and causes the ice to shift and to cause destruction to any structure which extends through the ice. It has consequently become necessary at such locations to provide means for removing the pier or landing dock from the water during the winter months, to save them from the severe destructive forces of the ice and wind. Unfortunately, many structures are so designed that although they may be removed from the lake they have sometimes required someone to enter the water to do so, and often have been complicated and expensive, and moreover, have not been foolproof in operation.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide a portable pier or landing dock which is so constructed and has mounting means so designed that it may be mounted at the lakeshore with a portion thereof extending over the water, and which may be readily removed from the water for storage during the winter months.
It is a further object to provide such a structure which is strong and which will withstand the rigors of normal use.
It is a further object to provide a portable structure of the type described which may be readily removed from the water for storage on shore during the winter months.
It is still further an object to provide a portable pier or landing dock which is relatively simple to construct, operate, and maintain, and which is relatively inexpensive.
Still further objects and advantages of the invention will appear as the description proceeds.
To the accomplishment of the foregoing and related ends, the invention, then, consists of the portable pier or landing dock herein fully described and particularly pointed out in the claims, the annexed drawings and the following description setting forth in detail certain illustrative embodiments of the invention, such disclosed embodiments illustrating, however, but several of the various ways in which the principle of the invention may be used.
BRIEF DESCRIPTION OF THE DRAWINGS
In the annexed drawings:
FIG. 1 is a side elevational view of the portable pier of the invention shown in a position completely removed from the water.
FIG. 2 is a side elevational view of the pier structure itself of FIG. 1, in extended and operational position; and
FIG. 3 is a cross-sectional view taken at the line III--III of FIG. 2, looking in the direction of the arrows.
DESCRIPTION OF THE SPECIFIC EMBODIMENT
Referring more particularly to FIGS. 1, 2 and 3, the portable pier or landing dock 10 of the invention is shown and comprises a pair of pier members 11 and 12 hingedly joined together. The pier member 11 is formed of upper rail members 17 formed of a material such as 2 × 2 × 1/8 inch angle iron, and terminal cross members 18, FIG. 2, of angle iron, bottom rail members 19 formed of a material such as 1-inch standard pipe, and end members 21 and 22, FIG. 1, of angle iron joining the upper rail members 17 and the bottom rail members 19 together. Zigzag lateral supports 23 formed of material such as 1/2-inch steel bar also connect the rail members 17 to the rail members 19. A plurality of planks or slats 24, formed of a material as for example 1-inch by 8-inch redwood, are affixed to the rail members 17 by suitable means such as studs or bolts. A plurality of inverted-V truss supports 20 of a material such as 1/2-inch rod connect and are welded to the bottom pier members 19 at the terminal cross members 18.
The pier member 11 is pivotally anchored at its proximal end by means of a pair of spaced-apart vertical channel members 25 welded to a mounting plate 26 and having standard roller bearing assemblies 27 mounted therein. The plate 26 is mounted in concrete 28 by means of rods or lugs affixed to the plate and embedded in the concrete. A shaft 41 supported by end plate 42 affixed at the proximal end of the pier member 11 is journaled through the roller bearing assemblies 27, thereby providing a hinge mount for the pier member 11.
The pier member 12 is similarly constructed and comprises upper rail members 29, terminal cross members 30 of angle iron connecting the ends of upper rail members 29, bottom rail members 31 formed of one-inch pipe, inverted-V truss members 20 connecting the bottom rail members 31 with the terminal cross members 30, end members 33 and 34, and a zigzag lateral support member 35. Planks or slats 36 are suitably affixed by studs or bolts to the upper rail members 29.
The pier members 11 and 12 are hinged together by means of a hinge member 37, FIG. 1, comprising a pair of hinged support plates 38 affixed to the pier member 11 and a pair of hinged support plates 39 affixed to the pier member 12. The support plates 38 and 39 are connected together by means of a hinge pin 40.
The distal end of the pier member 12 is provided with a supporting leg in the form of a roller-float assembly 46 comprising vertical pipe 47 affixed to the pier member 12 by means of a pair of gusset plates 48. The assembly 46 additionally includes a pair of adjustable support rods 49 telescoped within the pipes 47. Pins 53 extend through any of a series of apertures provided in the pipe member 47 and in the support rods 49 to make the position of the assembly adjustable. A shaft 54 extends through T-couplings 55 and 56 affixed at the ends of the rods 49. Rotatably mounted over the shaft 54 is a roller float 57 which may be formed of sheet metal and being hollow inside. The float 57 is in the shape of a spool having flanges 61 and 62 and a reduced axial portion 63. The float is preferably filled with a foamed plastic material such as polystyrene, and the foam may be applied in place through apertures 64 provided in one of the flanges.
The hinge joint 37 is so structured that when the pier members are lowered and extended into operating position, the ends of the pier members are in abutment and limit the rotation of the hinge joint to a position where the pier members are substantially in a straight line.
Raising and lowering of the pier structure is accomplished by means of a winch assembly 68, FIG. 1, comprising a winch 69 having a wire cable 70 wound thereon, one end of the cable being affixed to the distal end of the pier member 11. The winch 69 is suitably affixed to a dead anchor 71 comprising a pipe or rod 76 slidably telescoped into a pipe 72 of about four inches in diameter which is mounted in concrete 74 through a steel pocket 75.
Although the portable pier assembly may be installed and operated in the form described, it has been found advantageous to incorporate additionally a truss rod 80 comprising a tubular outer member 81 and an inner member 82 such as a rod or pipe slidably telescoped therein. The tubular member 81 is pivotally mounted at its end to a pivot flange 83 embedded in the concrete 28 by means of a pin 84. The rod member 82 is pivotally mounted at its end to a pivot flange 85 affixed to the pier member 12, by means of a pin 86. A limit flange 87 is mounted over the rod member 82 and affixed in the proper position as by welding. The flange permits the rod member 82 to slide out of the tubular member 81, but limits the position to which it may move inwardly so that the proper extending movement is applied to the pier member 12 when the assembly is lowered.
FIGS. 2 and 3 illustrate the portable pier in its fully extended and operating position. In this position, the float 57 rests on the bottom of the lake and the telescoping structure is adjusted so that the pier is in substantially level position. Additionally, during normal operation the portion of the winch assembly 68 comprising the winch 69 and pipe 72 may be withdrawn and stored. When it is desired to retract the pier from the water for storage, as during the winter season, the pipe 72 and winch assembly 68 are remounted into position. As the winch 69 is operated and the cable 70 retrieved, the distal end of the pier member 11 and the proximal end of the pier member 12 are raised in the air and pulled rearward. This causes the distal end of the pier member 12 to ride on the roller float 57 rearwardly. As the structure rises, the force applied to the float 57 decreases until eventually its buoyancy causes it to rise to the surface of the water. With the structure fully retracted, it assumes the position illustrated in FIG. 1. In this position it may be safely stored during the winter months where it will not be damaged by the movement of water and ice in the lake.
The pier structure is placed in operating position by slowly lowering the structure into the water by slowly releasing the cable 70 from the winch 69. In the embodiment not utilizing the truss rod structure 80, it may be necessary manually to extend the distal end of the pier member 12 as the assembly is lowered until the roller-float assembly 46 becomes operable, after which the pier end floats and rolls into place. However, in the embodiment utilizing the truss rod structure 80, the truss rod is geometrically arranged so that it serves to extend the distal end of the pier member 12 as the entire structure is lowered. After the roller-float assembly 46 becomes operable, it assists in extending the pier end until the roller-float assembly 46 becomes operable, after which it floats and then sinks and rolls until the pier structure is fully extended. During the launching process when the truss rod is operable to extend the pier structure, the flange 87 engages the end of the tubular member 81. However, after the roller-float assembly 46 becomes operable, the rod member 82 is free to slide outwardly and to extend a sufficient distance to permit the pier to become fully extended. When the pier is fully extended, the roller-float assembly 46 is fully extended and the pier leveled by removing the pin 53, FIG. 2, adjusting the assembly to the proper height so that the roller-float rests on the bottom of the lake, and reinserting the pin.
The portable pier or adjustable dock of the present invention has many advantages over prior art structures. First, it avoids the risk of severe damage which often results during the winter months when ice forms and then is broken up. The structure is simple to operate and may be readily extended and retracted by a single individual. Moreover, the structure is relatively simple and inexpensive to build, and because it avoids the rigors imposed on permanent piers during the winter months, it lasts considerably longer than permanently fixed piers. Additionally, the improved structure utilizing a truss rod further facilitates placing the structure in position for normal use from its storage position.
Other modes of applying the principle of my invention may be employed, instead of the one explained, change being made as regards the apparatus herein disclosed, provided the means stated by any of the following claims or the equivalent of such stated means be employed.
The present invention relates to piers and landing docks for use at lakes or rivers for providing access to and docking facilities for small boats, and more particularly is concerned with a pier of the type described which may be readily raised out of the water for storage during periods of nonuse.
Piers and landing docks used at lake resorts, homes at private lakes, or other places where boats are generally moored are subject to considerable damage and destruction during the winter months when ice forms across the lake. The danger of damage and destruction is particularly severe when the ice breaks up in the spring and causes the ice to shift and to cause destruction to any structure which extends through the ice. It has consequently become necessary at such locations to provide means for removing the pier or landing dock from the water during the winter months, to save them from the severe destructive forces of the ice and wind. Unfortunately, many structures are so designed that although they may be removed from the lake they have sometimes required someone to enter the water to do so, and often have been complicated and expensive, and moreover, have not been foolproof in operation.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide a portable pier or landing dock which is so constructed and has mounting means so designed that it may be mounted at the lakeshore with a portion thereof extending over the water, and which may be readily removed from the water for storage during the winter months.
It is a further object to provide such a structure which is strong and which will withstand the rigors of normal use.
It is a further object to provide a portable structure of the type described which may be readily removed from the water for storage on shore during the winter months.
It is still further an object to provide a portable pier or landing dock which is relatively simple to construct, operate, and maintain, and which is relatively inexpensive.
Still further objects and advantages of the invention will appear as the description proceeds.
To the accomplishment of the foregoing and related ends, the invention, then, consists of the portable pier or landing dock herein fully described and particularly pointed out in the claims, the annexed drawings and the following description setting forth in detail certain illustrative embodiments of the invention, such disclosed embodiments illustrating, however, but several of the various ways in which the principle of the invention may be used.
BRIEF DESCRIPTION OF THE DRAWINGS
In the annexed drawings:
FIG. 1 is a side elevational view of the portable pier of the invention shown in a position completely removed from the water.
FIG. 2 is a side elevational view of the pier structure itself of FIG. 1, in extended and operational position; and
FIG. 3 is a cross-sectional view taken at the line III--III of FIG. 2, looking in the direction of the arrows.
DESCRIPTION OF THE SPECIFIC EMBODIMENT
Referring more particularly to FIGS. 1, 2 and 3, the portable pier or landing dock 10 of the invention is shown and comprises a pair of pier members 11 and 12 hingedly joined together. The pier member 11 is formed of upper rail members 17 formed of a material such as 2 × 2 × 1/8 inch angle iron, and terminal cross members 18, FIG. 2, of angle iron, bottom rail members 19 formed of a material such as 1-inch standard pipe, and end members 21 and 22, FIG. 1, of angle iron joining the upper rail members 17 and the bottom rail members 19 together. Zigzag lateral supports 23 formed of material such as 1/2-inch steel bar also connect the rail members 17 to the rail members 19. A plurality of planks or slats 24, formed of a material as for example 1-inch by 8-inch redwood, are affixed to the rail members 17 by suitable means such as studs or bolts. A plurality of inverted-V truss supports 20 of a material such as 1/2-inch rod connect and are welded to the bottom pier members 19 at the terminal cross members 18.
The pier member 11 is pivotally anchored at its proximal end by means of a pair of spaced-apart vertical channel members 25 welded to a mounting plate 26 and having standard roller bearing assemblies 27 mounted therein. The plate 26 is mounted in concrete 28 by means of rods or lugs affixed to the plate and embedded in the concrete. A shaft 41 supported by end plate 42 affixed at the proximal end of the pier member 11 is journaled through the roller bearing assemblies 27, thereby providing a hinge mount for the pier member 11.
The pier member 12 is similarly constructed and comprises upper rail members 29, terminal cross members 30 of angle iron connecting the ends of upper rail members 29, bottom rail members 31 formed of one-inch pipe, inverted-V truss members 20 connecting the bottom rail members 31 with the terminal cross members 30, end members 33 and 34, and a zigzag lateral support member 35. Planks or slats 36 are suitably affixed by studs or bolts to the upper rail members 29.
The pier members 11 and 12 are hinged together by means of a hinge member 37, FIG. 1, comprising a pair of hinged support plates 38 affixed to the pier member 11 and a pair of hinged support plates 39 affixed to the pier member 12. The support plates 38 and 39 are connected together by means of a hinge pin 40.
The distal end of the pier member 12 is provided with a supporting leg in the form of a roller-float assembly 46 comprising vertical pipe 47 affixed to the pier member 12 by means of a pair of gusset plates 48. The assembly 46 additionally includes a pair of adjustable support rods 49 telescoped within the pipes 47. Pins 53 extend through any of a series of apertures provided in the pipe member 47 and in the support rods 49 to make the position of the assembly adjustable. A shaft 54 extends through T-couplings 55 and 56 affixed at the ends of the rods 49. Rotatably mounted over the shaft 54 is a roller float 57 which may be formed of sheet metal and being hollow inside. The float 57 is in the shape of a spool having flanges 61 and 62 and a reduced axial portion 63. The float is preferably filled with a foamed plastic material such as polystyrene, and the foam may be applied in place through apertures 64 provided in one of the flanges.
The hinge joint 37 is so structured that when the pier members are lowered and extended into operating position, the ends of the pier members are in abutment and limit the rotation of the hinge joint to a position where the pier members are substantially in a straight line.
Raising and lowering of the pier structure is accomplished by means of a winch assembly 68, FIG. 1, comprising a winch 69 having a wire cable 70 wound thereon, one end of the cable being affixed to the distal end of the pier member 11. The winch 69 is suitably affixed to a dead anchor 71 comprising a pipe or rod 76 slidably telescoped into a pipe 72 of about four inches in diameter which is mounted in concrete 74 through a steel pocket 75.
Although the portable pier assembly may be installed and operated in the form described, it has been found advantageous to incorporate additionally a truss rod 80 comprising a tubular outer member 81 and an inner member 82 such as a rod or pipe slidably telescoped therein. The tubular member 81 is pivotally mounted at its end to a pivot flange 83 embedded in the concrete 28 by means of a pin 84. The rod member 82 is pivotally mounted at its end to a pivot flange 85 affixed to the pier member 12, by means of a pin 86. A limit flange 87 is mounted over the rod member 82 and affixed in the proper position as by welding. The flange permits the rod member 82 to slide out of the tubular member 81, but limits the position to which it may move inwardly so that the proper extending movement is applied to the pier member 12 when the assembly is lowered.
FIGS. 2 and 3 illustrate the portable pier in its fully extended and operating position. In this position, the float 57 rests on the bottom of the lake and the telescoping structure is adjusted so that the pier is in substantially level position. Additionally, during normal operation the portion of the winch assembly 68 comprising the winch 69 and pipe 72 may be withdrawn and stored. When it is desired to retract the pier from the water for storage, as during the winter season, the pipe 72 and winch assembly 68 are remounted into position. As the winch 69 is operated and the cable 70 retrieved, the distal end of the pier member 11 and the proximal end of the pier member 12 are raised in the air and pulled rearward. This causes the distal end of the pier member 12 to ride on the roller float 57 rearwardly. As the structure rises, the force applied to the float 57 decreases until eventually its buoyancy causes it to rise to the surface of the water. With the structure fully retracted, it assumes the position illustrated in FIG. 1. In this position it may be safely stored during the winter months where it will not be damaged by the movement of water and ice in the lake.
The pier structure is placed in operating position by slowly lowering the structure into the water by slowly releasing the cable 70 from the winch 69. In the embodiment not utilizing the truss rod structure 80, it may be necessary manually to extend the distal end of the pier member 12 as the assembly is lowered until the roller-float assembly 46 becomes operable, after which the pier end floats and rolls into place. However, in the embodiment utilizing the truss rod structure 80, the truss rod is geometrically arranged so that it serves to extend the distal end of the pier member 12 as the entire structure is lowered. After the roller-float assembly 46 becomes operable, it assists in extending the pier end until the roller-float assembly 46 becomes operable, after which it floats and then sinks and rolls until the pier structure is fully extended. During the launching process when the truss rod is operable to extend the pier structure, the flange 87 engages the end of the tubular member 81. However, after the roller-float assembly 46 becomes operable, the rod member 82 is free to slide outwardly and to extend a sufficient distance to permit the pier to become fully extended. When the pier is fully extended, the roller-float assembly 46 is fully extended and the pier leveled by removing the pin 53, FIG. 2, adjusting the assembly to the proper height so that the roller-float rests on the bottom of the lake, and reinserting the pin.
The portable pier or adjustable dock of the present invention has many advantages over prior art structures. First, it avoids the risk of severe damage which often results during the winter months when ice forms and then is broken up. The structure is simple to operate and may be readily extended and retracted by a single individual. Moreover, the structure is relatively simple and inexpensive to build, and because it avoids the rigors imposed on permanent piers during the winter months, it lasts considerably longer than permanently fixed piers. Additionally, the improved structure utilizing a truss rod further facilitates placing the structure in position for normal use from its storage position.
Other modes of applying the principle of my invention may be employed, instead of the one explained, change being made as regards the apparatus herein disclosed, provided the means stated by any of the following claims or the equivalent of such stated means be employed.