Not applicable to this application.
1. Field of the Invention
The present invention relates generally to a portable lift and more specifically it relates to a portable modular lift system that may be easily transported to a lifting location and compactly stored when not in use.
2. Description of the Related Art
Any discussion of the related art throughout the specification should in no way be considered as an admission that such related art is widely known or forms part of common general knowledge in the field.
Conventional lift systems have been in use for years for elevating workers, materials and the like to elevated locations. Lift systems are utilized by maintenance workers, sound and light professionals, home owners, warehouse owners and the like to reach elevated locations. Conventional lift systems utilize one or more vertically orientated masts. The masts are typically attached to the side or wall of the structure to be worked upon with bracing. The masts may be comprised of a unitary structure or a modular structure. The modular masts are comprised of mast sections that are secured together in a vertical manner with conventional fasteners to form an elongated mast structure. A support platform is movably positioned upon the masts and may be elevated/lowered utilizing an electric motor or other power source. An example of a unitary mast configuration utilized for elevating workers and materials is U.S. Pat. No. 6,981,573 to Nickel and owned by Reechcraft, Inc. The Reechcraft patent discloses a pair of vertical posts that support a movable platform between thereof and that utilizes braces attached between the posts and the wall structure.
One problem with conventional lift systems is that they are relatively heavy making them difficult to transport to a work area. Another problem with conventional lift systems is that they are time consuming to assemble because they require tools and manual assembly with fasteners to attach the modular masts together.
A further problem with conventional lift systems is that they are difficult to transport and are not designed to be easily utilized in smaller sized locations like the interiors of buildings. Another problem with conventional lift systems is that they typically require more than one worker to assemble, utilize and disassemble. A further problem with conventional lift systems is that they require attachment of the masts to the side of a building structure being worked upon. Another problem with conventional lift systems is that they are expensive and complex making them difficult to utilize on smaller projects.
Because of the inherent problems with the related art, there is a need for a new and improved portable modular lift system that may be easily transported to a lifting location and compactly stored when not in use.
The invention generally relates to a portable lift which includes a support base having a plurality of base wheels, a plurality of mast sections connectable to one another to form a vertical mast, a support platform movably positioned upon the vertical mast, and a drive unit connected to the support platform to elevate and lower the support platform upon the mast sections. The mast sections include a plurality of receiver apertures within a first end and a plurality of locking pins extending from a second end that are catchably received within the corresponding receiver apertures.
There has thus been outlined, rather broadly, some of the features of the invention in order that the detailed description thereof may be better understood, and in order that the present contribution to the art may be better appreciated. There are additional features of the invention that will be described hereinafter and that will form the subject matter of the claims appended hereto. In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction or to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of the description and should not be regarded as limiting.
Various other objects, features and attendant advantages of the present invention will become fully appreciated as the same becomes better understood when considered in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the several views, and wherein:
a is a magnified upper perspective view illustrating two mast sections being initially positioned together in an unlocked state with the securing lever in the released position and with the locking lever in the locked state to prevent movement of the securing levers.
b is a magnified upper perspective view illustrating the two mast sections with the locking lever moved to a release state to allow for movement of the securing levers.
c is a magnified upper perspective view illustrating the securing lever positioned in the locked position to lock the locking pins within the receiver apertures by the locking shaft.
d is a magnified upper perspective view illustrating the securing lever positioned in the locked position and the locking lever in the locked state to prevent movement of the securing levers.
a is a side cutaway view of a first mast section positioned above a second mast section prior to connection thereof
b is a side cutaway view of the first mast section connected to the second mast section with the locking shaft rotated to lock the locking pins.
a is a bottom end view of a mast section showing the locking lever in the locked state to prevent movement of the securing levers.
b is a bottom end view of a mast section showing the locking lever in the release state to prevent movement of the securing levers.
a is a side cutaway view showing the securing levers in the released position extending outwardly thereby preventing passage of the guide wheels upwardly onto the next mast section.
b is a side cutaway view showing the securing levers in the released position extending outwardly with the guide wheels engaging the extended securing levers thereby preventing passage of the guide wheels upwardly onto the next mast section.
c is a side cutaway view showing the securing levers in the locked position thereby allowing passage of the guide wheels upwardly onto the next mast section.
a is a side view of an upper mast section positioned above a lower mast section with a sequencing pin extending from the lower end in a first position of the upper mast section and aligned with a sequencing aperture extending within the upper end of the lower mast section in a first position corresponding to the sequencing pin.
b is a side view of an upper mast section positioned above a lower mast section with a sequencing pin extending from the lower end in a second position of the upper mast section and aligned with a sequencing aperture extending within the upper end of the lower mast section in a second position corresponding to the sequencing pin.
c is a side view of an upper mast section positioned above a lower mast section with a sequencing pin extending from the lower end in a third position of the upper mast section and aligned with a sequencing aperture extending within the upper end of the lower mast section in a third position corresponding to the sequencing pin.
d is a side view of an upper mast section positioned above a lower mast section with a sequencing pin extending from the lower end in a fourth position of the upper mast section and aligned with a sequencing aperture extending within the upper end of the lower mast section in a fourth position corresponding to the sequencing pin.
a is a top end view of a mast section illustrating the sequencing aperture.
b is a bottom end view of the mast section illustrating the sequencing pin.
a is a side cutaway view of the outer leg with no weight supported by the corresponding adjustment member.
b is a side cutaway view of the outer leg with weight supported by the corresponding adjustment member thereby releasing the locking detent and the corresponding finger member.
c is a side cutaway view of the outer leg with weight supported by the corresponding adjustment member and with the corresponding finger member removed from the corresponding guide member.
Turning now descriptively to the drawings, in which similar reference characters denote similar elements throughout the several views,
The support base 20 includes a plurality of legs that extend outwardly along a horizontal plane. The legs may extend outwardly in various patterns such as but not limited to an X-shaped pattern. There are preferably at least two front set of legs and two rear set of legs as illustrated in
The support base 20 preferably has a width of 30 inches or less when the plurality of legs are in the compact state to allow for passage through doorways and other narrow areas. The support base 20 preferably has a width of 53 inches or more when the plurality of legs are in the extended state to provide stability to the present invention when in use.
The support base 20 preferably includes a plurality of wheels to assist in the transportation of the present invention from one location to another. As illustrated in
The plurality of wheels further preferably includes a plurality of caster wheels 21 that allow for horizontal movement of the present invention upon a flat surface. The base wheels 28 are larger than the caster wheels 21 to provide for increased mobility over uneven terrain. The base wheels 28 may be constructed of a non-pneumatic tire structure (e.g. flat free tire) or a pneumatic tire structure. The base wheels 28 are preferably sufficient in size to allow for transport of the present invention up and down stairs. The bottom ends of the base wheels 28 are preferably higher than the lower end of the caster wheels 21 so that only the caster wheels 21 are supporting the present invention when in a substantially horizontal state and only the base wheels 28 support the present invention when inclined rearwardly. The caster wheels 21 are connected to the distal portions of the inner legs 22 to provide for maximum stability during movement when in the compact storage position as illustrated in
The outer legs 24 each include an adjustment member 26 as illustrated in
The outer legs 24 are secured within the inner legs 22 by a detent structure or fastener. Each of the inner legs 22 include a guide member 70 having an upper tapered opening that receives a corresponding finger member 55 extending downwardly from the support platform 50. The finger members 55 are preferably attached to a pair of extended members 56 that extend from the support platform 50 as illustrated in
Each inner leg 22 includes a lower biased unit 72 that is positioned within a lower interior portion of the inner leg 22 below each of the guide members 70 to allow for selective engagement of the upper end of the lower biased unit 72 with the lower end of the finger members 55. A flanged end member 74 extends horizontally from the lower biased unit 72 and extends through a slot 25 within a partition member 23 within the outer leg 24.
Each outer leg 24 preferably includes an upper bushing 80 and a lower bushing 82 as illustrated in
When the pad 27 is not bearing any weight, the first engaging member 86 is adjacent to and touching the lower bushing 82 as illustrated in
It is preferable to have a single vertical mast constructed from the plurality of interconnected mast sections 30 as illustrated in
The vertical mast extends upwardly from the support base 20 as illustrated in
While not required, it is preferable to have a base mast that is permanently or semi-permanently attached to the support base 20 as illustrated in
The plurality of mast sections 30 each have a first end 31 and a second end 37. The first end 31 may be comprised of the upper end or the lower end of the respective mast section 30. The second end 37 of the respective mast section 30 is opposite of the first end 31 and may be comprised of the upper end or the lower end of the respective mast section 30. The first end 31 and the second end 37 of the mast sections 30 are preferably parallel with respect to one another.
The first end 31 of each mast section 30 includes a first coupler and the second end 37 of each mast section 30 includes a second coupler. The first coupler is removably connectable to the second coupler to removably connect the plurality of mast sections 30 in a vertical and aligned manner. The first coupler and the second coupler allow for secure and relatively non-moving attachment of the mast sections 30 with respect to one another.
As shown in
Each of the plurality of mast sections 30 preferably has a rectangular cross section (e.g. square shaped) and are comprised of extruded aluminum to provide for a cost-effective, lightweight structure capable of supporting the support platform 50 along with cargo. It can be appreciated that the mast sections 30 may be comprised of various other cross sections (e.g. circular, hexagonal, triangular, etc.) The first end 31 and the second end 37 of each of the mast sections 30 is preferably flat and transverse with respect to the longitudinal axis of the respective mast sections 30 to maximize the physical contact between the first end 31 of a first mast section 30 and a second end 37 of an adjacent mast section 30. Each of the mast sections 30 includes a track 33 on one side thereof that the drive unit 60 engages. The track 33 for each of the mast sections 30 is aligned when assembled into the vertical mast. Each of the mast sections 30 also includes the opposing pair of side channels 34. The side channels 34 for each of the mast sections 30 are aligned when assembled into the vertical mast thereby creating a single elongated pair of side channels 34 within the vertical mast allowing free passage of the guide wheels 54.
The first coupler and the second coupler are each preferably comprised of a plurality of receiver apertures 32 or a plurality of locking pins 38 that are received within the receiver apertures 32. If the first coupler is comprised of the receiver apertures 32 then the second coupler is comprised of the locking pins 38 to allow for interconnection of two or more mast sections 30. The first coupler is aligned with the second coupler for each of the mast sections 30 to allow for interconnection of each of the mast sections 30.
a through 8d illustrate the receiver apertures 32 within the first end 31 (the first end 31 is shown as the upper end in the figures whereas the first end 31 could be the lower end alternatively). The receiver apertures 32 are formed to have an upper tapered portion to help guide the locking pins 38 into the receiver apertures 32 with the middle to lower portions of the receiver apertures 32 formed to snugly receive the locking pins 38 with limited movement to ensure a stable vertical mast when constructed. The plurality of receiver apertures 32 are preferably comprised of four corner receiver apertures 32 positioned adjacent to each corner of the first end 31 of the mast section 30 as illustrated in
The plurality of receiver apertures 32 removably receive the plurality of locking pins 38 in a catchable manner. The locking pins 38 have a length sufficient to ensure secure reception within the receiver apertures 32 (e.g. at least one inch). The locking pins 38 are also preferably comprised of four corner locking pins 38 positioned adjacent to each corner of the second end 37 of the mast section 30 The plurality of locking pins 38 each include a locking channel 39 that extends through a side portion of the locking pins 38 transverse with respect to the longitudinal axis of the locking pins 38. The locking channel 39 allows the locking shaft 44 to pass through and selectively prevent the locking pins 38 from exiting the receiver apertures 32. The plurality of locking pins 38 extend parallel with respect to a longitudinal axis of the plurality of mast sections 30.
One or more locking shafts 44 are rotatably positioned within each of the plurality of mast sections 30 and partially extend into at least two of the plurality of receiver apertures 32 to selectively engage the locking pins 38. As shown in
A securing lever 40 is connected to the locking shaft 44 to allow for manual rotation of the locking shaft 44. Each locking shaft 44 includes a securing lever 40, so as illustrated in the
A locking lever 46 is rotatably attached to the second end 37 of a mast section 30 above a lower mast section 30 as illustrated in
The support platform 50 is adapted to be movably connected to the vertical mast.
The support platform 50 includes a sliding support 52 extending from the support platform 50 that has a U-shaped structure that is positioned about three sides of the vertical mast. The sliding support 52 includes a plurality of guide wheels 54 that are movably received within the side channels 34 of the vertical mast to allow for relatively free upward and downward movement of the support platform 50 upon the vertical mast. It is preferable to have at least two guide wheels 54 for each of the side channels 34 within the vertical mast, with one of the guide wheels 54 positioned within an upper portion of the sliding support 52 and another of the guide wheels 54 positioned within a lower portion of the sliding support 52 to provide for increased stability and to prevent binding during operation. The diameter of the guide wheels 54 is slightly smaller than the width of the side channels 34 within the vertical mast to limit movement thereof.
A drive unit 60 is connected to the support platform 50 that is adapted to elevate and lower the support platform 50 upon the vertical mast. The drive unit 60 may include an actuator (e.g. electric motor, hydraulic motor) or a drive connector 62 to attach an outside actuator (e.g. a drill, hand crank). The drive unit 60 preferably includes an automatic braking system that prevents accidental lowering of the support platform 50 if the actuator should fail or is accidentally removed. The drive unit 60 mechanically engages the track 33 extending along a substantial portion of the length of the vertical mast utilizing a sprocket or other mechanical drive device. U.S. Pat. No. 6,981,573 to Nickel illustrates an exemplary drive unit 60 and is hereby incorporated by reference herein.
An emergency winch 12 is attached to the support base 20 that has a tether connectable to an emergency connector 13 attached to the support platform 50 to allow for an individual at the base of the present invention to lower the support platform 50 where the operator of the present invention is unable to. The emergency winch 12 draws the support platform 50 downwardly overcoming the braking force applied by the automatic breaking system within the drive unit 60 thereby forcing the support platform 50 to lower.
At least one mast storage device 58 extends outwardly from the support platform 50 as illustrated in
In use, the user transports the present invention in the compact storage position (
The respective adjustment members 26 for each of the outer legs 24 are lowered by rotating the adjustment members 26 until the caster wheels 21 are no longer supporting the present invention.
The support platform 50 will not be allowed to move upwardly unless all of the finger members 55 are allowed to freely pass through and out of the guide members 70. Free movement of the finger members 55 within the guide members 70 requires an upward pressure to be applied to each of the adjustment members 26 causing the first engaging member 84 to inwardly push the second engaging member 86 thereby causing the elongated shaft 88 to depress the corresponding locking detent 57 sufficiently so that the locking detent 57 does not catch upon the lower end of the corresponding guide member 70 as illustrated in
After the user has tested the stability of the support base 20, the user may then enter the support platform 50 and begin assembly of the vertical mast with the mast sections 30 as shown in
Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although methods and materials similar to or equivalent to those described herein can be used in the practice or testing of the present invention, suitable methods and materials are described above. All publications, patent applications, patents, and other references mentioned herein are incorporated by reference in their entirety to the extent allowed by applicable law and regulations. In case of conflict, the present specification, including definitions, will control. The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof, and it is therefore desired that the present embodiment be considered in all respects as illustrative and not restrictive. Any headings utilized within the description are for convenience only and have no legal or limiting effect.
I hereby claim benefit under Title 35, United States Code, Section 120 of U.S. patent application Ser. No. 13/536,140 filed Jun. 28, 2012. This application is a continuation of the Ser. No. 13/536,140 application. The Ser. No. 13/536,140 application is currently pending and is scheduled to be granted on Oct. 21, 2014 with a patent number of U.S. Pat. No. 8,863,899. The Ser. No. 13/536,140 application is hereby incorporated by reference into this application. The Ser. No. 13/536,140 application claims priority to U.S. Provisional Application No. 61/502,421. I hereby claim benefit under Title 35, United States Code, Section 119(e) of U.S. provisional patent application Ser. No. 61/502,421 filed Jun. 29, 2011. The 61/502,421 application is now abandoned. The 61/502,421 application is hereby incorporated by reference into this application.
Number | Date | Country | |
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61502421 | Jun 2011 | US |
Number | Date | Country | |
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Parent | 13536140 | Jun 2012 | US |
Child | 14517534 | US |