AU2006200061B2 - Lifter - Google Patents

Description

P/00/011 Regulation 3.2

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT

ORIGINAL

TO BE COMPLETED BY APPLICANT Name of Applicant: Actual Inventor: Address for Service: Invention Title: Chin Piao Huang Chin Piao Huang A.P.T. Patent and Trade Mark Attorneys PO Box 222, Mitcham, SA 5062 Lifter The following statement is a full description of this invention, including the best method of performing it known to me:-

LIFTER

BACKGROUND OF THE INVENTION Field of the Invention: The present invention relates to a lifter for lifting plate materials in a building construction to an overhead place for mounting and more particularly, to a simple structure of lifter, which is safe and convenient in use.

Description of the Related Art: During a building construction it may require several workers to affix a big ceiling panel.

At first, the big ceiling panel must be lifted by two workers and then closely attached to the ceiling, and then a third worker uses a nailing gun to affix the ceiling panel to the ceiling. During installation, the two workers on the floor must hold the ceiling panel firmly in position so that the third worker can affix the ceiling panel to the ceiling accurately. However, the two workers who stand on the floor to hold the ceiling panel overhead cannot support the ceiling panel stably on the roof for long. Vibration of the hands of the two workers on the floor may result in inaccurate positioning of the ceiling panel on the ceiling.

Taiwan patent application number 92126757 discloses a lifter for use to lift plate members in a building construction. This design of lifter is also an invention of the present invention. According to this design, the lifter comprises a wheeled stand, a barrel supported on the wheeled stand, and a telescopic extension bar mounted in the barrel, cable pulleys respectively pivotally provided at the barrel and the barrel and the telescopic extension bar, a first cable, which has one end fixedly connected to the bottom end of the telescopic extension bar and the other end coupled to a winding mechanism, and a second cable, which extends over the cable pulley at the top end of the telescopic extension bar with the first end fixedly connected to the top end of the barrel and the second end affixed to the bottom end of the telescopic extension bar. This design of lifter is functional. However, the use of the two cables complicates the structure.

For the purposes of this specification the word "comprising" means "including but not limited to", and the word "comprises" has a corresponding meaning. Also a reference within this specification to a document is not to be taken as an admission that the disclosure therein constitutes common general knowledge in Australia.

SUMMARY OF THE INVENTION The present invention has been accomplished under the circumstances in view.

According to one aspect of the present invention, the lifter comprises lifter comprises a barrel, a hollow first extension bar inserted into the barrel and axially movable in and out of the top end of the barrel, a hollow second extension bar inserted into the first extension bar and axially movable in and out of the top end of the first extension bar, a first pulley holder and a second pulley holder respectively fixedly provided at the periphery of the top end of the barrel at two opposite sides; a first cable pulley and a second cable pulley respectively pivotally mounted in the first pulley holder and the second pulley holder, a guide roller pivotally provided at the bottom end of the first extension bar, a third pulley holder fixedly provided at the periphery of the top end of the first extension bar at one side, a third cable pulley pivotally mounted in the third pulley holder, and a cable, which has a first end fixedly connected to the bottom end of the second extension bar and a second end extending out of the second extension bar over the third cable pulley and the second cable pulley to the inside of the barrel and then extending over the guide roller and then the first cable pulley to the outside of the barrel, and a winch mounted on the barrel and connected to the second end of the cable for rolling up the cable to lift the second extension bar out of the first extension bar and the first extension bar out of the barrel. According to another aspect of the present invention, the lifter further comprises a wheeled a stand provided at the bottom end of the barrel for allowing movement of the collapsed lifter on the floor. The wheeled stand comprises a sliding socket coupled to and movable along the barrel, a center post fixedly provided at the bottom end of the barrel, a plurality of legs respectively pivoted to the sliding socket, a plurality of links respectively coupled between the legs and the center post, and a plurality of wheels respectively provided at the legs for supporting the legs on the floor.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an elevational view of a lifter according to the present invention.

FIG. 2 is a perspective view of the winch of the lifer according to the present invention, showing internal structure of the winch.

FIG. 3 is a schematic drawing showing the arrangement of the ratchet wheel and pawl of the ratchet mechanism on the winch of the lifter according to the present invention.

FIG. 4 is a longitudinal view in section of the lifter according to the present invention.

FIG. 5 is a schematic sectional view showing the lifting operation of the lifter according to the present invention.

FIG. 6 is a schematic drawing showing an auxiliary wheel assembly attached to the collapsed tripod of the lifter according to the present invention.

FIG. 7 is a cross sectional view of an alternate form of the present invention.

FIG. 8 is a cross sectional view of another alternate form of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. 1, a lifter in accordance with the present invention is shown comprising a barrel 10, a first extension bar 20 axially slidably mounted in the barrel a second extension bar 30 axially slidably mounted in the first extension bar 20, a bracket (not shown) fixedly provided at the top side of the second extension bar 30, a cable 40 coupled to the first extension bar 20 and the second extension bar 30, and a winch 50 mounted on the barrel 10 for operation by the user to take up or let off the cable 40 and to further move the first extension bar 20 axially relative to the second extension bar 30 and the barrel 10 or to move the first extension bar 20 and the second tension bar 30 axially relatively to the barrel 10. The first extension bar 20 is a round tube. The second extension bar 30 is a rectangular bar. The barrel 10, the first extension bar 20 and the second extension bar 30 can be different special-shape tubes, however there must be a longitudinal gap in between the barrel 10 and the first extension bar and a longitudinal gap in between the first extension bar 20 and the second extension bar for the passing of the cable Referring to FIGS. 2~5 and HFIG. 1 again, the barrel 10 has a first pulley holder fixedly mounted on the periphery at the top at one side to hold a first cable pulley 16, and a second pulley holder 26 fixedly mounted on the periphery at the top at the opposite side to hold a second cable pulley 27. The barrel 10 has the top end fixedly mounted with an end cap 22. The first extension bar 20 is inserted through the end cap 22 into the inside of the barrel 10, having a bottom end suspending inside the barrel and fixedly mounted with a guide roller 25, which partially protruding over two opposite side openings (not shown) near the bottom end of the first extension bar 20, and a guide block 21, which guides axial movement of the first extension bar 20 along the barrel and stops the first extension bar 20 from falling out of the end cap 22 at the barrel and a top end disposed outside the barrel 10 and fixedly mounted with an end cap 32 and a third pulley holder 35. The third pulley holder 35 holds a third pulley 36. The barrel has the top end fixedly mounted with an end cap 22. The end cap 22 has a cable hole 23 for the passing of the cable 40. The second extension bar 30 is inserted through the end cap 32 into the inside of the first extension bar 20, having a bottom end suspending inside the first extension bar 20 and fixedly mounted with a guide block 31, which guides axial movement of the second extension bar 30 along the first extension bar and stops the second extension bar 30 from falling out of the end cap 32 at the first extension bar 20, and a top end disposed outside the first extension bar 20 and fixedly mounted with bracket (not shown) for holding the load. The cable 40 has one end fixedly fastened to the bottom end of the second extension bar 30, and the other end extending out of the first extension bar 20 over the third cable pulley 36 and then extending over the second cable pulley 27 into the inside of the barrel 10 and then extending over the guide roller 25 and then through the cable hole 23 and then extending over the first cable pulley 16 to the winch 50. Further, a first locating frame 28 is fixedly provided at the second pulley holder 26, and a first stop bar 29 is coupled to the first locating frame 28. The first stop bar 29 has a ring 290 on the middle. The user can operate the first stop bar 29 to move the ring 290 in and out of the alignment position.

When moved into the alignment position, the ring 290 is in axial alignment with the center axis of the barrel 10 for allowing the first extension bar 20 to pass through the ring 290 into the inside of the barrel 10. On the contrary, when moved out of the alignment position, the first stop bar 29 stops the first extension bar 20 from downward movement. Further, a second locating frame 37 is fixedly provided at the third pulley holder 35, and a second stop bar 38 is coupled to the second locating frame 37. The second stop bar 38 has a ring 380 on the middle. The user can operate the second stop bar 38 to move the ring 380 in and out of the alignment position. When moved into the alignment position, the ring 380 is in axial alignment with the center axis of the first extension bar 20 for allowing the second extension bar 30 to pass through the ring 380 into the inside of the first extension bar 20. On the contrary, when moved out of the alignment position, the second stop bar 38 stops the second extension bar 30 from downward movement.

Referring to FIGS. 1~3 again, the winch 50 comprises a first frame bar 51 pivoted to the periphery of the barrel 10, a second frame bar 52, which has a bottom end pivoted to the barrel 10 and a top end coupled to the first frame bar 51 and movable along the length of the first frame bar 51 for supporting the first frame bar 51, and a winding mechanism 53 fixedly mounted on the free end of the first frame bar 51. The user can move the second frame bar 52 relative to the first frame bar 51 between two positions, the extended position where the second frame bar 52 support the first frame bar 51 in a sloping position away from the barrel 10 and the received position where the first frame bar 51 and the second frame bar 52 are received together and closely attached to the barrel The winding mechanism 53 comprises a bobbin 54, which has two end flanges 540 and holds one end of the cable 40 and is rotatable to roll up the cable 40, a driving shaft 56 arranged in parallel to the bobbin 54, a transmission shaft 55 arranged in parallel between the bobbin 54 and the driving shaft 56, and a crank handle 57 for operation by the user to rotate the driving shaft 56. Further, the bobbin 54 has one end fixedly mounted with a driven gear 541. The transmission shaft 55 has an output gear 553 fixedly provided at one end thereof and meshed with the driven gear 541 at the bobbin 54, a big transmission gear 551 fixedly provided near the other end, and a small transmission gear 552 spaced between the big transmission gear 551 and the output gear 553. The driving shaft 56 is axially movably supported on an axle sleeve 560 inside the winding mechanism 53, having a first drive gear 561 adapted to engage the big transmission gear 551 and a second drive gear 562 adapted to engage the small transmission gear 562. The user can operate the crank handle 57 to move the driving shaft 56 between a first position to force the first drive gear 561 into engagement with the big transmission gear 551 or a second position to force the second drive gear 562 into engagement with the small transmission gear 552 for enabling the crank handle 57 to rotate the bobbin 54 at one of two different speeds. Further, a ratchet mechanism 60 is provided to limit the direction of rotation of the crank handle 57 and the bobbin 54. The ratchet mechanism 60 comprises a ratchet wheel 61 fixedly mounted on one end of the transmission shaft 55, and a pawl 62 pivoted to one end of the bobbin 54. The pawl 62 has a tip 63 rested on the sloping teeth of the ratchet wheel 61. Further, the pawl 62 is supported on a torsional spring (not shown), which imparts a biasing force to the pawl 62 to force the tip 63 of the pawl 62 into engagement with the sloping teeth of the ratchet wheel 61.

Further, a stand, for example, a tripod 70 is provided at the bottom side of the barrel The tripod 70 comprises a sliding socket 71 coupled to and axially movable along the barrel 10, a center post 75 fixedly fastened to the bottom end of the barrel 10, a plurality of legs 72 respectively pivoted to the sliding socket 71, a plurality of links 76 respectively coupled between the center post 75 and the legs 72 for enabling the legs 72 to be moved relative to the barrel 10 between the extended operative position and the received non-operative position, and wheels 75 respectively pivotally mounted on the bottom ends of the legs 72. Further, an auxiliary wheel assembly 80 may be used and fastened to the bottom ends of two of the legs 72 of the collapsed tripod 70 for enabling the collapsed lifter to be conveniently moved from place to place (see FIG. 6).

By means of the auxiliary wheel assembly 80, the lifter can conveniently be moved to the work place (see FIG. After the lifter has been moved to the work place, the tripod is extended out, and the materials to be lifted are put on the bracket (not shown) at the top end of the second extension bar 30, and then extend out the first frame bar 51 and the second frame bar 52, and then operate the crank handle 57 to roll up the cable 40 to lift the first extension bar 20 out of the barrel 10 and then the second extension bar 30 out of the first extension bar 20 (see FIGS. 4 and When approaching the expected elevational position, operate the crank handle 57 to move the driving shaft 56 relative to the axle sleeve 560 and to further force the second drive gear 562 into engagement with the small transmission gear 552 and then rotate the crank handle 57 to lift the second extension bar 30 at a relatively slower speed. When rotating the crank handle 57 in the reversed direction after disengagement of the pawl 64 from the ratchet wheel 61 and after the first stop bar 29 and the second stop bar 38 have been respectively moved to the respective alignment positions, the cable 40 is let off, and the second extension bar 30 is lowered into the inside of the first extension bar 20 and then the first extension bar 20 is lowered into the inside of the barrel FIG. 7 is a cross sectional view of an alternate form of the present invention. According to this embodiment, the barrel 10A has an octagonal cross section, the first extension bar has a rectangular cross section, and the second extension bar 30A has a hexagonal cross section. This embodiment achieves the same effect as the aforesaid first embodiment shown in FIGS. 1-6.

FIG. 8 is a cross sectional view of another alternate form of the present invention.

According to this embodiment, the barrel O10B has a circular cross section, the first extension bar 20B has a hexagonal cross section, and the second extension bar 30B has a rectangular cross section. This embodiment achieves the same effect as the aforesaid first embodiment shown in FIGS. 1-6.

As indicated above, the invention provides a lifter, which has the following advantages and industrial values: 1. The structure of the lifter is simple and inexpensive to manufacture, and one single cable 40 is sufficient to achieve the extending and receiving actions of the lifter.

2. Through the first drive gear 561 and the second drive gear 562, the user can control the lifting speed, achieving accurate positioning of the lifter.

3. The ratchet mechanism 60 prevents sudden release of the cable 40, assuring safety use of the lifter.

4. By means of the auxiliary wheel assembly 80, the lifter can conveniently be carried from place to place.

Although particular embodiments of the invention have been described in detail for purposes of illustration, various modifications and enhancements may be made without departing from the spirit and scope of the invention. Accordingly, the invention is not to be limited except as by the appended claims.

Claims (10)

1. A lifter comprising: a barrel, said barrel having a top end and a bottom end; a hollow first extension bar inserted into said barrel and axially movable in and out of the top end of said barrel, said first extension bar having a top and a bottom Send; Sa hollow second extension bar inserted into said first extension bar and Saxially movable in and out of the top end of said first extension bar; Oa first pulley holder and a second pulley holder respectively fixedly provided at the periphery of the top end of said barrel at two opposite sides; a first cable pulley pivotally mounted in said first pulley holder; a second cable pulley pivotally mounted in said second pulley holder; a guide roller pivotally provided at the bottom end of said first extension bar; a third pulley holder fixedly provided at the periphery of the top end of said first extension bar at one side; a third cable pulley pivotally mounted in said third pulley holder; a cable, said cable having a first end fixedly connected to the bottom end of said second extension bar and a second end extending out of said second extension bar over said third cable pulley and said second cable pulley to the inside of said barrel and then extending over said guide roller and then said first cable pulley to the outside of said barrel; and a winch mounted on the said barrel and connected to the second end of said cable for rolling up said cable to lift said second extension bar out of said first extension bar and said first extension bar out of said barrel, the winch including a bobbin engagable by a first gear means or a second gear means, the bobbin rotatable around an axis of rotation and adapted to receive the cable thereon, the first gear means adapted to rotate the bobbin for the winding up and unwinding of said cable and the second gear means adapted to rotate the bobbin for the winding up and unwinding of said cable, wherein the first and second gear means rotate the bobbin at different rates. 1OA o

2. The lifter as claimed in claim 1, further comprising a wheeled a stand provided C) 0 at the bottom end of said barrel for allowing movement of the lifter on the floor.

3. The lifter as claimed in claim 1, further comprising a guide block fixedly provided at the bottom end of said \0 IN first extension bar along said barrel, and an end cap fixedly provided at the top end of said barrel for stopping said guide block inside said barrel.

4. The lifter as claimed in claim 1, further comprising a guide block fixedly provided at the bottom end of said second extension bar for guiding axial movement of said second extension bar along said first extension bar, and an end cap fixedly provided at the top end of said first extension bar for stopping said guide block inside said first extension bar.

5. The lifter as claimed in claim 1, wherein said winch comprises a first frame bar pivoted to the periphery of said barrel, a second frame bar, said second frame bar having a first end pivoted to said barrel and a second end coupled to along said first frame bar and movable along said first frame bar between two distal ends of said first frame bar, and a winding mechanism fixedly mounted on one end of said first frame bar remote from said barrel, said winding mechanism comprising s a bobbin, which holds the second end of said cable and rotatable to roll up said cable, a fixed axle sleeve, a driving shaft arranged in parallel to said bobbin and axially movably supported on said axle sleeve, a transmission shaft arranged in parallel between said bobbin and said driving shaft, a crank handle for operation by the user to rotate said driving shaft, a driven gear fixedly mounted on one end of said bobbin, an output gear fixedly provided at one end of said transmission shaft and meshed with said driven gear, a big transmission gear and a small transmission gear respectively fixedly mounted on said transmission shaft, a first drive gear fixedly mounted on said driving shaft for meshing said big transmission gear, and a second drive gear fixedly mounted on said driving shaft for meshing said small transmission gear.

6. The lifter as claimed in claim 5, wherein said winch further comprises a ratchet mechanism adapted to limit the direction of rotation of said crank handle and said bobbin, said ratchet mechanism comprising a ratchet wheel fixedly mounted on one end of said transmission shaft, and a pawl pivoted to one end of said bobbin and forced by spring means into engagement with said ratchet wheel.

7. The lifter as claimed in claim 1, further comprising a wheeled a stand provided at the bottom end of said barrel for allowing movement of the lifter on the floor, said wheeled stand comprising a sliding socket coupled to and movable along said barrel, a center post fixedly provided at the bottom end of said barrel, a plurality of legs respectively pivoted to said sliding socket, a plurality of links respectively coupled between said legs and said center post, and a plurality of wheels respectively provided at said legs for supporting said legs on the floor.

8. The lifter as claimed in claim 7, further comprising an auxiliary wheel assembly for attaching to said wheeled stand for allowing the lifter to be moved on the floor after said legs of said wheeled stand has been received together.

9. The lifter as claimed in claim 1, further comprising a locating frame fixedly provided at said second pulley holder, a stop bar coupled to said locating frame and movable between a first position to stop said first extension bar in an extended position and a second position for allowing said first extension bar to move in and out of said barrel.

10. The lifter as claimed in claim 1, further comprising a locating frame fixedly provided at said third pulley holder, a stop bar coupled to said locating frame and movable between a first position to stop said second extension bar in an extended position and a second position for allowing said second extension bar to move in and out of said first extension bar. Dated this 9th day of January 2006 CHIN PIAO HUANG By their Patent Attorneys A.P.T. Patent and Trade Mark Attorneys