Patent Publication Number: US-6702064-B2

Title: Lifter having tiltable support rack assembly

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an elevator or a lifter, and more particularly to a lifter having a tiltable support rack assembly for supporting and moving or elevating workers and/or objects upward to various elevated working positions. 
     2. Description of the Prior Art 
     For washing or cleaning the outside walls of buildings, various kinds of scaffolds are required to be set up and attached onto the outside portions of the walls for acting as an aerial ladder and for carrying workers to the desired elevations. These equipments include a complicated configuration having a large number of parts or elements that may not be easily assembled for working purposes and that may not be easily disengaged from each other for storing purposes. In addition, these equipments may not be easily moved elsewhere. 
     The present applicant had developed another typical elevator or lifter that may be easily moved or carried with the workers, and that may be easily used for elevating the workers to the desired elevations. The mobile lifter has been issued as U.S. Pat. No. 5,533,593 to Huang, and comprises one or more actuators and a support rack for supporting and moving or elevating the workers and/or the objects upward to various elevated working positions. However, the mobile lifter may not be easily used for elevating the heavy planer members, such as the boards, the plates, or the like. 
     The present invention has arisen to mitigate and/or obviate the afore-described disadvantages of the conventional elevators or lifters. 
     SUMMARY OF THE INVENTION 
     The primary objective of the present invention is to provide a lifter including a tiltable support rack assembly for supporting and moving or elevating workers and/or objects upward to various elevated working positions. 
     The other objective of the present invention is to provide a lifter that may be easily moved from place to place for supporting and elevating workers and/or objects upward to various elevated working positions at different locations. 
     In accordance with one aspect of the invention, there is provided a lifter comprising an elevator including an upper end, a beam provided above the upper end of the elevator for supporting an object to be elevated, and means for tiltably securing the beam on the upper end of the elevator. 
     The tiltably securing means includes a base secured on the upper end of the elevator, and a seat for securing to the beam, the seat including a first end rotatably secured to the base with a shaft. 
     The seat includes two sides each having an oblong hole for slidably receiving the shaft, and means for resiliently supporting the shaft in the seat. 
     The resiliently supporting means includes a bracket secured to the shaft, and a spring engaged between the bracket and the seat. The bracket includes a column engaged through the spring for retaining the spring in place. 
     The seat includes a strip secured to the seat and having an orifice formed therein for slidably receiving the column. 
     The tiltably securing means includes a plate secured on the seat, a board secured to the beam and rotatably secured on the plate, and means for positioning the board to the plate. 
     The plate includes an upward extending peg engaged through the plate and the board, the positioning means includes a positioning pin attached to the seat and engaged through the plate and the board. 
     The board includes two or more apertures formed therein, the seat includes means for biasing the positioning pin to engage with the either of the apertures of the board. 
     A device is further provided for locking the seat to the base, and includes a fastener threaded to the second end of the seat and selectively engaging with the base, for selectively locking the seat to the base. 
     The beam includes at least one passage formed therein, and a post slidably engaged in the passage of the beam, and means for fastening the post to the beam. 
     The post includes a plurality of orifices formed therein, the fastening means includes a latch pivotally secured to the beam and having a stud provided on a first end thereof, and means for biasing the stud to engage into either of the orifices of the post. 
     The beam includes at least one arm rotatably secured to a first side thereof, and a spring blade secured in the beam and engaged with the arm for retaining the arm between a first position perpendicular to the beam and a second position parallel to the beam. 
     A retaining member may rotatably secured to the post and the arm, and including a non-circular bar, and a coupler secured to the post and the arm and having a depression formed therein for receiving the non-circular bar. 
     Further objectives and advantages of the present invention will become apparent from a careful reading of a detailed description provided hereinbelow, with appropriate reference to accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a partial exploded view of a lifter in accordance with the present invention; 
     FIG. 2 is a partial perspective view illustrating a tiltable support rack assembly for the lifter; 
     FIGS. 3 and 4 are partial exploded views illustrating a tiltable support device of the lifter for supporting the racks; 
     FIG. 5 is a side view of the lifter, in which a portion of the tiltable support rack assembly of the lifter is cut off for illustrating the inner structure of the tiltable support rack assembly for the lifter; 
     FIG. 6 is a partial end view illustrating the operation of the tiltable support rack assembly for the lifter; 
     FIGS. 7 and 8 are top plan schematic views illustrating the operation of the tiltable support rack assembly for the lifter; 
     FIG. 9 is a partial top view illustrating the attachment of an end retaining member to the tiltable support rack assembly for the lifter; and 
     FIG. 10 is a partial side view illustrating the attachment of the end retaining member to the tiltable support rack assembly for the lifter. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to the drawings, and initially to FIG. 1, an elevator or a lifter in accordance with the present invention comprises a mobile lifter member or an elevator  20  including a telescopic device  21  extended upward and retractable, and including three or more legs  23  pivotally secured thereto and openable to an outward working position as shown in FIG.  1 . The legs  23  each includes a wheel  24  attached thereto for allowing the elevator  20  to be easily moved to the other positions. One example of the elevators  20  has been disclosed in U.S. Pat. No. 5,533,593 to Huang, which is taken as a reference for the present invention. The elevator  20  includes an extension  25  secured to the bottom and having a pad  26  selectively rotatable downward to engage with the ground, for stably positioning the elevator  20  at the selected or required position. 
     As shown in FIGS. 1-5, an adjustable support device  30  includes a base  32  having a hub  33  extended downward therefrom for engaging onto an upper rod  22  of the elevator  20 . A fastener  34  may be engaged through the hub  33  and engaged with the upper rod  22  of the elevator  20  for detachably securing the hub  33  of the base  32  to the rod  22  of the elevator  20 . The base  32  includes one or more barrels  320  formed or provided on one end thereof for receiving a shaft  35  therein. A seat  36  includes a chamber  42  formed therein for receiving the base  32 , and includes a pair of oblong holes  37  formed in the sides of one end thereof for slidably receiving the shaft  35 . 
     A strip  41  is secured in the bottom of the chamber  42  of the seat  36  with one or more fasteners  43 , and includes an orifice  46  formed in the middle portion thereof. A bracket  38  includes a space  381  formed between a pair of flaps  380  for receiving the shaft  35 . The flaps  380  each includes an aperture  381  formed therein for receiving a fastener  384  which may be engaged or secured to a hole  351  of the shaft  35 , for securing the shaft  35  to the bracket  38 . The bracket  38  includes a column  39  extended downward therefrom and slidably engaged through the orifice  36  of the strip  41 . A spring  40  is engaged on the column  39  and engaged between the bracket  38  and the strip  41  for resiliently supporting the bracket  38  and the shaft  35  within the chamber  42  of the seat  36 . 
     A plate, such as a disc-shaped plate  51  is secured onto the seat  36  with fasteners or by welding processes, and includes a peripheral skirt  511  extended downward therefrom and having a notch  52  formed therein for receiving a portion of the seat  36 . The seat  36  includes a peg  56  extended upward therefrom for engaging through a hole  513  of the plate  51  and for further solidly securing the plate  51  to the seat  36 . A positioning pin  531  is detachably or resiliently secured to the seat  36  with a spring  53 , and engageable through an orifice  514  of the plate  51  for further positioning the plate  51  to the seat  36 . 
     A board  54  includes a hole  57  formed in the center portion thereof for rotatably receiving the peg  56 , and includes one or more apertures  55  formed in the peripheral portion thereof for selectively receiving the positioning pin  531  and for positioning the board  54  to the plate  51  at the selected angular positions. A retaining ring  58  may be engaged onto the peg  56  and engaged with the board  54  for rotatably securing the board  54  to the plate  51 . The board  54  includes one or more fasteners  59  extended upward therefrom, for securing a beam  60  thereon (FIGS. 2,  5 ,  6 ), and for supporting the object  80  on the beam  60  and to be elevated by the elevator  20 . 
     For example, the spring  53  is engaged between two ears  363 ,  364  of the seat  36 , and has one end secured to the positioning pin  531  for biasing the positioning pin  531  upward through the ear  364  and for biasing the positioning pin  531  to engage through the orifice  514  of the plate  51 , and to selectively engage through either of the apertures  55  of the board  54 . The positioning pin  531  may be pulled away from the board  54  against the spring  53  with a ring  533 , for allowing the board  54  to be rotated and adjusted relative to the plate  51 . The positioning pin  531  may be biased by the spring  53  to engage into the other aperture  55  of the board  54  when the aperture  55  of the board  54  is aligned with the positioning pin  531 . 
     The beam  60  includes a pair of passages  62  formed therein for slidably receiving a pair of posts  63  which may be moved or extended outward of the beam  60  in opposite directions (FIGS. 2,  7 ); and includes two side grooves  64  formed therein. The posts  63  each includes a slot  67  formed therein, and each includes one or more orifices  68  formed therein. Two latches  69  each has a middle portion rotatably secured in the grooves  64  of the beam  60  with a pivot axle  692 , and each has a lock stud  693  secured or threaded to one end thereof. A spring  691  is engaged with the other end of the latch  69  for biasing the lock stud  693  to engage into either of the orifices  68  of the posts  63 , and for detachably securing the posts  63  to the beam  60 , and for allowing the posts  63  to be extended and adjusted inward and outward relative to the beam  60 . 
     As shown in FIGS. 1,  2  and  8 , two pairs or four arms  65  each has one end rotatably rotatably secured in the grooves  64  of the beam  60  with a pivot pole  74 , and each has a pad  73  secured to the other end for safely supporting the object  80 . Four spring blades  71  are secured in the beam  60  and engageable with the ends of the arms  65  (FIG.  8 ), for positioning the arms  65  at either the outward working position that is perpendicular to the beam  60  or at the inward storing position that is received in the grooves  64  of the beam  60 . 
     One or more retaining members  70  are hook-shaped and each includes an oblong or rectangular or non-circular bar  75  secured or provided in one end thereof, and/or each includes a hook  79  provided on the other end thereof for engaging with the object  80  (FIG.  2 ). A coupler  72  includes a depression  77  for receiving the non-circular bar  75  therein, and is secured to the respective arms  65  or posts  63  with fasteners  66 . The non-circular bar  75  may be retained in the depression  77  of the coupler  72 , but may be rotated relative to the coupler  72  for 180 degrees, for allowing the retaining members  70  to be rotated relative to the arms  65  or the posts  63  to an outward or upward working position as shown in FIG. 2 or as shown in dotted lines in FIGS. 9 and 10, or to an inward or downward storing position as shown in solid lines in FIG.  10 . 
     In operation, as shown in FIGS. 3,  6 , the shaft  35  is resiliently supported in the chamber  42  of the seat  36  with the spring  40  and the bracket  38 , and the ends of the shaft  35  are slidably received in the oblong holes  37  of the seat  36 , such that the seat  36  and thus the plate  51  and the board  54  may be slightly moved or rotated relative to the fastener  384  or may be vibrated relative to the seat  36 . The vibrating movement of the shaft  35  relative to the seat  36  may be limited by the sliding movement of the ends of the shaft  35  relative to the oblong holes  37  of the seat  36 . 
     As shown in FIG. 2, the object  80  may be elevated by the elevator  20  to the required height. As shown in FIG. 5, the seat  36  and the plate  51  and the board  54  and the beam  60  may be rotated relative to the base  32  about the shaft  35 , for allowing the objected  80  to be tilted and moved or easily disengaged from beam  60 . A fastener  44  may be threaded to a screw hole  361  (FIG. 4) that is formed in the other end of the seat  36  opposite to the shaft  35 , and may be engaged with the base  32  (FIG. 3) for securing the seat  36  to the base  32  and for preventing the seat  36  from rotating relative to the base  32 . 
     Accordingly, the lifter in accordance with the present invention includes a tiltable support rack assembly for supporting and moving or elevating workers and/or objects upward to various elevated working positions, and the lifter may be easily moved from place to place for supporting and elevating workers and/or objects upward to various elevated working positions at different locations. 
     Although this invention has been described with a certain degree of particularity, it is to be understood that the present disclosure has been made by way of example only and that numerous changes in the detailed construction and the combination and arrangement of parts may be resorted to without departing from the spirit and scope of the invention as hereinafter claimed.