AU2023285790A1 - Telescoping jack for lifting large capacity trucks - Google Patents

Abstract

A jack, comprising: a top plate having at least one adapter block mounted thereon and adapted to contact a load; a base plate positioned below the top plate; the top plate movable between a lowered position and a raised position to thereby lower and raise the load; and, at least one locking assembly adapted to lock the top plate in the raised position; wherein the at least one locking assembly includes a locking bar and a ratchet rack, the locking bar having an upper end and a lower end, the locking bar hinge mounted at the upper end proximate to the top plate, the ratchet rack inclining upward at an acute angle from the base plate toward the top plate and having at least one notch formed therein, the at least one notch adapted to receive and lock the lower end of the locking bar, and the lower end of the locking bar slidable up the ratchet rack and into the at least one notch as the top plate is moved from the lowered position to the raised position; wherein the ratchet rack is stationarily attached to the base plate; and, wherein a top adapter plate of the at least one adapter block is operable to slide between first and second positions on the top plate as the load is raised and lowered to thereby maintain alignment of the top and base plates below the load.

Description

TELESCOPING JACK FOR LIFTING LARGE CAPACITY TRUCKS

[0001] This application claims priority from United States

Patent Application No. 16/510,946, filed July 14, 2019, and

the entire content of such application is incorporated herein

by reference.

FIELD OF THE APPLICATION

[0002]This application relates to the field of jacks, and more

specifically, to a telescoping jack for lifting large capacity

trucks, such as open pit mining haulage trucks, and the like.

BACKGROUND

[0003] Large capacity open pit mining haulage trucks require

lifting or jacking to replace worn out or flat tires, for

example. Currently, a single lifting ram or cylinder based

jack is typically used for this purpose.

[0004] However, existing single cylinder jacks have several

disadvantages. First, they typically only lift one point or

corner of the truck or load at a time. Second, the single

cylinder is often heavy and awkward to handle and as such may

cause operator injuries and strains. Third, the operator

typically needs to stand under the truck while operating the

jack and as such the operator may be injured by falling debris

from the undercarriage of the truck. Fourth, the operator is

typically required to lock the lifted truck via safety stands

or lock collars while positioned under the lifted truck, which

may be dangerous. Fifth, existing jacks are slow to operate

typically requiring approximately 20 to 30 minutes per lift.

Sixth, as only one point or corner is lifted at a time by existing jacks, the lifted truck or load may become unstable when the entire front or rear is lifted at one time. Seventh, existing jacks are often unstable when subjected to side loading, for example, when a tire is pulled off the lifted truck. Finally, the cylinders of existing jacks are typically driven by an airline which may freeze up in cold climates.

[0005]Under pressure to improve both safety and efficiency

while lifting and securing the largest haulage trucks (e.g.,

up to 400 ton) in the world, mining companies require a safe

and cost effective jack for their truck maintenance needs.

[0006]A need therefore exists for an improved jack for lifting

large capacity trucks and the like. Accordingly, a solution

that addresses, at least in part, the above and other

shortcomings is desired.

SUMMARY OF THE APPLICATION

[0007]According to one aspect of the application, there is

provided a jack, comprising: a top plate adapted to contact a

load; an intermediate plate positioned below the top plate,

the intermediate plate having a channel formed therein; a base

plate positioned below the intermediate plate; a first pair of

actuators coupled between the base plate and the intermediate

plate, one of the first pair of actuators positioned on either

side of the channel; and, a second pair of actuators coupled

between the channel of the intermediate plate and the top

plate; wherein the first and second pairs of actuators are

operable to move the top plate and the intermediate plate

between respective lowered positions and respective raised

positions to thereby lower and raise the load.

[0008]According to another aspect of the application, there is provided a jack, comprising: a top plate having at least one adapter block mounted thereon and adapted to contact a load; an intermediate plate positioned below the top plate; a base plate positioned below the intermediate plate; a first pair of actuators coupled between the base plate and the intermediate plate; and, a second pair of actuators coupled between respective lowered portions of the intermediate plate and the top plate; wherein one of the first pair of actuators is positioned on the base plate on either side of the respective lowered portions of the intermediate plate; wherein the first and second pairs of actuators are operable to move the top plate and the intermediate plate between respective lowered positions and respective raised positions to thereby lower and raise the load; and, wherein a top adapter plate of the at least one adapter block is operable to slide between first and second positions on the top plate as the load is raised and lowered to thereby maintain alignment of the top, intermediate, and base plates below the load.

BRIEF DESCRIPTION OF THE DRAWINGS

[0009]Features and advantages of the embodiments of the present application will become apparent from the following detailed description, taken in combination with the appended drawings, in which:

[0010]FIG. 1 is a front perspective view illustrating a jack in accordance with an embodiment of the application;

[0011]FIG. 2 is a front view thereof;

[0012] FIG. 3 is a rear view thereof;

[0013]FIG. 4 is a left side view thereof;

[0014] FIG. 5 is a top view thereof;

[0015]FIG. 6 is a bottom view thereof;

[0016]FIG. 7 is a front perspective view illustrating the jack

of FIG. 1 with the front hood and rear hood removed in

accordance with an embodiment of the application;

[0017]FIG. 8 is a top view thereof;

[0018]FIG. 9 is a rear perspective view illustrating the rear

strut, steering, and walking beam assembly of the jack of FIG.

7 in accordance with an embodiment of the application;

[0019]FIG. 10 is a front view thereof with the rear wheels

shown in a retracted position;

[0020]FIG. 11 is a rear view thereof with the rear wheels shown

in an extended position;

[0021]FIG. 12 is a front perspective view illustrating the main

lifting assembly of the jack of FIG. 1 with the top plate

shown in a lowered position in accordance with an embodiment

of the application;

[0022]FIG. 13 is a front view thereof;

[0023]FIG. 14 is a left side view thereof;

[0024]FIG. 15 is a top view thereof;

[0025]FIG. 16 is a front perspective view illustrating the main lifting assembly of the jack of FIG. 1 with the top plate shown in a partially raised position in accordance with an embodiment of the application;

[0026]FIG. 17 is a front view thereof;

[0027]FIG. 18 is a left side view thereof;

[0028]FIG. 19 is a top view thereof;

[0029]FIG. 20 is a front perspective view illustrating the main lifting assembly of the jack of FIG. 1 with the top plate shown in a fully raised position in accordance with an embodiment of the application;

[0030]FIG. 21 is a front view thereof;

[0031]FIG. 22 is a left side view thereof;

[0032]FIG. 23 is a top view thereof;

[0033]FIG. 24 is a cross-sectional view illustrating the main lifting assembly of the jack of FIG. 1 taken along line A-A in FIG. 23, in accordance with an embodiment of the application;

[0034]FIG. 25 is a cross-sectional view illustrating the main lifting assembly of the jack of FIG. 1 taken along line B-B in FIG. 23, in accordance with an embodiment of the application;

[0035]FIG. 26 is a front view illustrating one of the compact spherical bearing cylinder mounts shown in FIG. 24 in accordance with an embodiment of the application;

[0036] FIG. 27 is a cross-sectional view thereof taken along line C-C in FIG. 26;

[0037]FIG. 28 is a cross-sectional detail view illustrating the installation of the spherical bearing cylinder mounts in the main lifting assembly shown in FIG. 24 taken along line A-A in FIG. 23;

[0038]FIG. 29 is a left side view illustrating the jack of FIG. 1 positioned under the rear lifting point of a truck in accordance with an embodiment of the application;

[0039] FIG. 30 is a rear view thereof;

[0040] FIG. 31 is a left side view illustrating the jack of FIG. 1 positioned under the front lifting point of a truck in accordance with an embodiment of the application;

[0041] FIG. 32 is a rear view thereof;

[0042]FIG. 33 is a front perspective view illustrating a main lifting assembly for the jack of FIG. 1 with the top plate shown in a lowered position in accordance with another embodiment of the application;

[0043]FIG. 34 is a front view thereof;

[0044] FIG. 35 is a top view thereof;

[0045]FIG. 36 is a left side view thereof;

[0046] FIG. 37 is a cross-sectional view thereof taken along line A-A in FIG. 36;

[0047] FIG. 38 is a partially exploded front perspective view

illustrating the main lifting assembly of FIG. 33 in

accordance with an embodiment of the application;

[0048]FIG. 39 is a front view thereof;

[0049]FIG. 40 is a left side view thereof;

[0050] FIG. 41 is a cross-sectional view thereof taken along

line B-B in FIG. 40;

[0051] FIG. 42 is a fully exploded front perspective view

thereof;

[0052]FIG. 43 is a front perspective view illustrating a main

lifting assembly for the jack of FIG. 1 with the top plate

shown in a lowered position and equipped with sliding adapter

blocks and an adapter block mounting plate in accordance with

another embodiment of the application;

[0053]FIG. 44 is a front view thereof;

[0054]FIG. 45 is a top view thereof;

[0055]FIG. 46 is a left side view thereof;

[0056] FIG. 47 is a partially exploded front perspective view

illustrating the main lifting assembly of FIG. 43 in

accordance with an embodiment of the application;

[0057]FIG. 48 is a front view thereof;

[0058]FIG. 49 is a front perspective view illustrating one of

the sliding adapter blocks shown in FIG. 43 with the top adapter plate thereof shown in a first, unloaded, or retracted position in accordance with an embodiment of the application;

[0059]FIG. 50 is a rear perspective view thereof;

[0060] FIG. 51 is a top view thereof;

[0061]FIG. 52 is a front view thereof;

[0062]FIG. 53 is a right side view thereof;

[0063]FIG. 54 is a cross-sectional view thereof taken along line A-A in FIG. 52;

[0064]FIG. 55 is a bottom perspective view thereof with the top adapter plate thereof shown in second or rearward position;

[0065]FIG. 56 is a front perspective view thereof;

[0066] FIG. 57 is a top view thereof;

[0067]FIG. 58 is a front view thereof;

[0068]FIG. 59 is a right side view thereof;

[0069]FIG. 60 is a cross-sectional view thereof taken along line A-A in FIG. 58;

[0070]FIG. 61 is a bottom perspective view thereof with the top adapter plate thereof shown in a third or forward position;

[0071]FIG. 62 is a front perspective view thereof;

[0072] FIG. 63 is a top view thereof;

[0073]FIG. 64 is a front view thereof;

[0074]FIG. 65 is a right side view thereof;

[0075]FIG. 66 is a cross-sectional view thereof taken along line A-A in FIG. 64;

[0076]FIG. 67 is an exploded perspective view illustrating one of the sliding adapter blocks shown in FIG. 43 in accordance with an embodiment of the application;

[0077]FIG. 68 is bottom perspective view illustrating the top adapter plate of the sliding block adapter block of FIG. 67 in accordance with an embodiment of the application;

[0078]FIG. 69 is a rear perspective view thereof;

[0079] FIG. 70 is a top view thereof;

[0080]FIG. 71 is a front view thereof;

[0081]FIG. 72 is a right side view thereof;

[0082]FIG. 73 is a cross-sectional view thereof taken along line A-A in FIG. 71;

[0083] FIG. 74 is bottom perspective view illustrating the bottom adapter plate of the sliding block adapter block of FIG. 67 in accordance with an embodiment of the application;

[0084]FIG. 75 is a rear perspective view thereof;

[0085] FIG. 76 is a top view thereof;

[0086] FIG. 77 is a front view thereof;

[0087] FIG. 78 is a right side view thereof; and,

[0088]FIG. 79 is a cross-sectional view thereof taken along

line A-A in FIG. 77.

[0089]It will be noted that throughout the appended drawings,

like features are identified by like reference numerals.

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0090]In the following description, details are set forth to

provide an understanding of the application. In some

instances, certain structures, techniques and methods have not

been described or shown in detail in order not to obscure the

application.

[0091] The jack 100 of the present application provides an

integrated truck lifting solution. The jack 100 provides for

reduced truck maintenance costs by reducing the time required

to lift trucks for tire changing, repair, etc. In particular,

according to one embodiment, the present application provides

a jack 100 having a total collapsed height of approximately 33

inches with the ability to lift and extend linearly

approximately 30 inches for a total working extend height of

approximately 63 inches. This allows the jack 100 to fit under

and lift a range of differently sized large capacity open pit

mining haulage trucks 1000. In addition, the jack 100 has

multiple visual secondary mechanical locking assemblies 810,

820, 830, 840 that may support the entire load of a lifted

truck 1000 (e.g., 220 tons or 440,000 lbs, etc.). The

secondary mechanical locking assemblies 810, 820, 830, 840 are

visible to an operator of the jack 100 who may be positioned

at a safe distance away from the truck 1000 as it is lifted.

Furthermore, the jack 100 may be remotely controlled to lift and lock a truck 1000 using a handheld remote control unit or the like.

[0092] The jack 100 is a mobile lifting and locking device

designed to lift and lock in an elevated position, large

capacity trucks including both 300 and 400 ton open pit mining

haulage trucks. Advantageously, the jack 100 will work on both

sizes of trucks. The jack 100 includes a remote control unit

that allows an operator to maneuver the jack 100 under a truck

(or other load) 1000, lift the truck 1000, and lock the truck

1000 in a raised position (e.g., 1600, 2000) without the

operator having to venture underneath the truck 1000.

[0093]FIG. 1 is a front perspective view illustrating a jack

100 in accordance with an embodiment of the application. FIG.

2 is a front view thereof. FIG. 3 is a rear view thereof. FIG.

4 is a left side view thereof. FIG. 5 is a top view thereof.

And, FIG. 6 is a bottom view thereof.

[0094]According to one embodiment of the application, the jack

100 may include: a chassis, frame, or base plate 110 having an

upper surface 111 and a lower surface 112; a main lifting

assembly 200 mounted on the upper surface 111 of the base

plate 110; first and second retractable front wheels 131, 132

mounted to the upper surface 111 of the base plate 110 at the

front end 150, the front wheels 131, 132 movable from a

retracted position 133 as shown in FIGS. 1-6 to an extended

position (not shown); a rear strut, steering, and walking beam

assembly 300 mounted on the upper surface 111 of the base

plate 110 at the rear end 160; and, first and second

retractable rear wheels 141, 142 mounted within the rear strut, steering, and walking beam assembly 300, the rear wheels 141, 142 movable from a retracted position 143 as shown in FIG. 10 to an extended position 144 as shown in FIG. 11

(described below). The structural components (e.g., the base

plate 110, the main lifting assembly 200, etc.) of the jack

100 are typically made of metal (e.g., steel, etc.).

[0095]FIG. 7 is a front perspective view illustrating the jack

100 of FIG. 1 with the front hood 101 and rear hood 301

removed in accordance with an embodiment of the application.

And, FIG. 8 is a top view thereof.

[0096]According to one embodiment, the first and second

retractable front wheels 131, 132 are mounted to right and

left sides 170, 180 of the upper surface 111 of the base plate

110 via respective first and second outrigger arms 731, 732.

The outrigger arms 731, 732 may be controlled to extend and

retract the front wheels 131, 132, either together or

individually. The front wheels 131, 132 are generally extended

when the jack 100 is being positioned under a truck 1000 and

are retracted during lifting of the truck 1000.

[0097]According to one embodiment, the jack 100 may be self

propelled and has mounted on its base plate 110 a diesel

engine 710, fuel tank 720, battery 740, radiator 750, and

hydraulic tank 760 for powering the hydraulic motors (e.g.,

integrated with the outrigger arms 731, 732) associated with

the hydraulically driven front wheels 131, 132 and the

hydraulic cylinders 271, 272, 273, 274 of the main lifting

assembly 200. According to one embodiment, the operation and

positioning of the jack 100 is remotely controllable using a handheld remote control unit (not shown) operated by an operator or worker.

[0098]FIG. 9 is a rear perspective view illustrating the rear strut, steering, and walking beam assembly 300 of the jack 100 of FIG. 7 in accordance with an embodiment of the application. FIG. 10 is a front view thereof with the rear wheels 141, 142 shown in a retracted position 143. And, FIG. 11 is a rear view thereof with the rear wheels 141, 142 shown in an extended position 144.

[0099]According to one embodiment, the rear strut, steering, and walking beam assembly 300 of the jack 100 may include: a frame 310; a bumper 320 mounted to the frame 310 for protecting the rear wheels 141, 142; a hydraulic cylinder strut 330 mounted through the upper surface 311 of the frame 310; a walking beam (and axle) 340 coupled to the lower end the hydraulic cylinder strut 330, the walking beam (and axle) 340 in turn being coupled to the rear wheels 141, 142 below the upper surface 311; and, a hydraulic rotary actuator (e.g., capable of 180 degrees of rotation) 350 coupled to the upper end of the hydraulic cylinder strut 330 above the upper surface 311 of the frame 310. The hydraulic cylinder strut 330 is operable to move from a retracted position to an extended position and hence to move the rear wheels 141, 142 from a retracted position 143 above the lower surface 112 of the base plate 110 to an extended position 144 below the lower surface 112 of the base plate 110 where the wheels 141, 142 may come into contact with the ground (or other surface) 1010 for raising the jack 100 off the ground 1010 in preparation for movement or repositioning. The hydraulic rotary actuator 350 is operable to rotate the hydraulic cylinder strut 330 and hence the rear wheels 141, 142 coupled thereto for steering the jack 100 during movement or repositioning. The walking beam (and axle) 340 functions like a suspension arm allowing horizontal movement of the rear wheels 141, 142 so that both wheels remain in contact with the ground 1010.

[00100] The rear wheels 141, 142, hydraulic cylinder strut

330 and hydraulic rotary actuator 350 provide for smooth 180

degree rotational steering and, according to one embodiment, a

four inch straight vertical lift in the extended position 144.

[00101] According to one embodiment, the jack 100 may be

equipped for hydraulic front wheel direct drive and may

include an electronic differential control system for left and

right steering.

[00102] According to one embodiment, the front

drives/outriggers 731, 732 of the front wheels 131, 132 may

extend and retract approximately four inches which allows the

entire jack 100 to be selectively raised above and lowered to

the ground 1010. The operation of the two front outriggers

731, 732 may be synchronized with the operation of the strut

330 to provide smooth and level lifting and lowering of the

jack 100 which in turn improves alignment of the jack 100 with

the certified lifting points 1020, 1030 of the truck 1000.

[00103] FIG. 12 is a front perspective view illustrating the

main lifting assembly 200 of the jack 100 of FIG. 1 with the

top plate 210 (and intermediate plate 230) shown in a lowered

position 1200 in accordance with an embodiment of the application. FIG. 13 is a front view thereof. FIG. 14 is a left side view thereof. And, FIG. 15 is a top view thereof.

[00104] FIG. 16 is a front perspective view illustrating the main lifting assembly 200 of the jack 100 of FIG. 1 with the top plate 210 (and intermediate plate 230) shown in a partially raised position 1600 in accordance with an embodiment of the application. FIG. 17 is a front view thereof. FIG. 18 is a left side view thereof. And, FIG. 19 is a top view thereof.

[00105] FIG. 20 is a front perspective view illustrating the main lifting assembly 200 of the jack 100 of FIG. 1 with the top plate 210 (and intermediate plate 230) shown in a fully raised position 2000 in accordance with an embodiment of the application. FIG. 21 is a front view thereof. FIG. 22 is a left side view thereof. And, FIG. 23 is a top view thereof.

[00106] FIG. 24 is a cross-sectional view illustrating the main lifting assembly 200 of the jack 100 of FIG. 1 taken along line A-A in FIG. 23, in accordance with an embodiment of the application. And, FIG. 25 is a cross-sectional view illustrating the main lifting assembly 200 of the jack 100 of FIG. 1 taken along line B-B in FIG. 23, in accordance with an embodiment of the invention.

[00107] According to one embodiment, the main lifting assembly 200 may include: a base lifting assembly (or frame) 220 mounted on the upper surface 111 of the base plate 110; an intermediate lifting assembly (or frame) 240 mounted over the base lifting assembly 220 and coupled (i.e., one or more of attached, connected, joined, bolted, welded, screwed, pinned, hinged, etc.) thereto; a top lifting assembly (or frame) 250 mounted over the intermediate lifting assembly 240 and coupled thereto; first and second compact spherical bearing cylinder mounts 410, 420; and, first, second, third, and fourth locking assemblies 810, 820, 830, 840.

[00108] According to one embodiment, the base lifting assembly (or frame) 220 may be mounted on the upper surface 111 of the base plate 110 and may have first and second telescoping linear guide columns 261, 262 and first and second main hydraulic lifting cylinders 271, 272 mounted therein. Each of the first and second main hydraulic lifting cylinders 271, 272 has a piston rod end 276 and a cylinder barrel end 275, the cylinder barrel end 275 of each of the first and second main hydraulic lifting cylinders 271, 272 may be mounted on the upper surface 111 of the base plate 110. Each of the first and second telescoping linear guide columns 261, 262 has a barrel end 263, a first stage end 264, and a second stage end 265. The barrel end 263 of each of the first and second telescoping linear guide columns 261, 262 may be mounted on the upper surface 111 of the base plate 110.

[00109] According to one embodiment, the intermediate lifting assembly 240 may have an intermediate plate 230 having a lower surface 232 and an upper surface 231. The intermediate plate 230 may have a central channel 234 formed therein. The left and right portions 233, 235 of the intermediate plate 230 on either side of the channel 234 are at the same level (or height) while the middle portion or channel 234 of the intermediate plate is at a lower level (or height). The intermediate plate 230 may be positioned over and parallel or approximately parallel to the base plate 110. The lower surface 232 of the left and right portions 233, 235 of the intermediate plate 230 may be coupled to the piston rod ends

276 of the first and second main hydraulic lifting cylinders

271, 272 of the base lifting assembly 220, respectively. The

lower surface 232 of the left and right portions 233, 235 of

the intermediate plate 230 may also be coupled to the first

stage ends 264 of the first and second telescoping linear

guide columns 261, 262, respectively. The upper surface 231 of

the middle portion or channel 234 of the intermediate plate

230 may have third and fourth main hydraulic lifting cylinders

273, 274 mounted thereto. Each of the third and fourth main

hydraulic lifting cylinders 273, 274 has a piston rod end 276

and a cylinder barrel end 275, the cylinder barrel end 275 of

each of the third and fourth main hydraulic lifting cylinders

273, 274 may be mounted on the upper surface 231 of the middle

portion or channel 234 of the intermediate plate 230.

[00110] Advantageously, by using a channelled intermediate

plate 230, the overall height of the main lifting assembly 200

may be reduced.

[00111] According to one embodiment, the top lifting

assembly 250 may have a top plate 210 having a lower surface

212 and an upper surface 211. The top plate 210 may be

positioned over and parallel or approximately parallel to the

intermediate plate 230. The lower surface 212 of the top plate

210 may be coupled to the piston rod end 276 of each of the

third and fourth main hydraulic lifting cylinders 273, 274 of

the intermediate lifting assembly 240 via respective compact spherical bearing mounts 410, 420 (described below). The lower surface 212 of the top plate 210 may also be coupled to the second stage end 265 of each of the first and second telescoping linear guide columns 261, 262. The upper surface 211 of the top plate 210 may be adapted for contacting the lifting points 1020, 1030 of a truck 1000 (or other load).

[00112] Referring to FIG. 24, according to one embodiment, the four main hydraulic lifting cylinders 271, 272, 273, 274 operate at 4500 psi hydraulic pressure creating a total tonnage lift of 220 tons. The main lifting assembly 200 is designed for the sequenced operation of all four main hydraulic lifting cylinders 271, 272, 273, 274 when raising, lowering, and maintaining level on off balanced loads. The main hydraulic lifting cylinders 271, 272, 273, 274 are connected in series (i.e., daisy chain) to each other, which together with the structure of the main lifting assembly 200 described above, eliminates or reduces the need for electronic motion control.

[00113] Advantageously, the channeled intermediate lifting plate 230, integrated main hydraulic lifted cylinders 271, 272, 273, 274, and compact spherical bearing mounts 410, 420 combined with the telescoping linear guide columns 261, 262 allows for a low profile collapsed height for the jack 100 of only 33 inches while providing a linear lifting working stroke of 30 inches. The telescoping linear guide columns 261, 262 provide the required stability to handle a full 220 ton off balanced load.

[00114] According to one embodiment, each of the first, second, third, and fourth locking assemblies 810, 820, 830, 840 may have an inclined ratchet rack (or plate) 811, a locking bar 812, and a lock release assembly 850. The ratchet rack 811 may be a right-angled triangle (or approximately right-angled triangle) shaped gusset plate having a horizontal or approximately horizontal base, a vertical or approximately vertical side, and a hypotenuse or inclined side. The base of the ratchet rack 810 is mounted to the upper surface 111 of the base plate 110 proximate a side (e.g., the left side 180) of the base plate 110. The vertical side of the ratchet rack 810 may be mounted to the side (e.g., the front side) of the base lifting assembly (or frame) 220. The ratchet rack 811 may be built into or function as a gusset plate strengthening the connection of the base lifting assembly 110 to the base plate 210. The inclined side of the ratchet rack 811 has a number (e.g., five) of teeth or notches 813 formed therein for receiving a lower pin or roller 814 of the locking bar 812. The locking bar 812 may include first and second elongate plates or members 816, 817 that are coupled and spaced apart at a lower end 818 by the lower pin or roller 814 and at an upper end 819 by an upper pin or roller 815. The upper end 819 of the locking bar 812 is pin or hinge mounted (e.g., using the upper pin or roller 815) to the side (e.g., the front side) of the top lifting assembly (or frame) 250 allowing the lower end 818 of the locking bar 812 to swing or rotate inwards toward the base lifting assembly 220 and outwards away from the base lifting assembly 220 by rotation about its pin or hinge.

[00115] Each locking assembly (e.g., 820) is gravity

activated and the notches 813 on the inclined side of the

ratchet rack 811 provides multiple (e.g., seven for five

notches) pre-set locking positions. Advantageously, as each

locking assembly 820 is externally mounted on the jack 100,

engagement of the locking bars 812 in the ratchet rack 811

remains fully visible to an operator located at a safe

distance from the truck 1000 or load.

[00116] Referring to FIGS. 12-15, when the top plate 210 of

the jack 100 is in a lowered position 1200, for each locking

assembly (e.g., 810), the roller 814 of the locking bar 812 is

positioned below the lowest notch (e.g., the first notch) on

the ratchet rack 811. Referring to FIGS. 16-19, as the top

plate 210 is lifted to a partially raised position 1600, the

roller 814 of the locking bar 812 rolls or slides up the

ratchet rack 811 and is engaged with a higher notch 813 (e.g.,

the third notch) on the ratchet rack 811. Referring to FIGS.

-23, as the top plate 210 is lifted to a fully raised

position 2000, the roller 814 of the locking bar 812 rolls or

slides further up the ratchet rack 811 and is engaged with a

yet higher notch 813 (e.g., the fifth notch) on the ratchet

rack 811.

[00117] The notches 813 formed in the ratchet rack 811 are

shaped or angled upward to allow the roller 814 of the locking

bar 812 to travel upward over the notches 813 as the top plate

210 is lifted. Advantageously, the upward angling of the

notches 813 prevents the roller 814 of the locking bar 812

from travelling downward over the notches 813 as the top plate

210 is lowered. In this way, gravity is used to lock the locking bars 812 in position to secure the raised truck 1000 or load.

[00118] Referring to FIG. 25, to allow the roller 814 of the

locking bar 812 to travel downward over the notches 813 when

the top plate 210 is lowered, each locking assembly (e.g.,

840) is equipped with a lock release assembly 850. The lock

release assembly 850 includes a lock release plate 851 coupled

to a lock release hydraulic cylinder 852. The lock release

plate 851 (e.g., a '-4 inch plate) has a right-triangle shape

similar to that of the ratchet rack 811. The lock release

hydraulic cylinder 852 is operable to move the lock release

plate 851 from a retracted position 2510 (as shown in FIG. 16)

to an extended position 2520 (as shown in FIG. 25). When moved

to the extended position 2520, the angled side of the lock

release plate 851 extends beyond the angled side of the

ratchet rack 811, contacts the roller 814 of the locking bar

812, urges the roller 814 out of the notch 813 in the ratchet

rack 811, thus allowing the roller 814 and locking bar 812 to

slide downward over the notches 813 in the ratchet rack 811.

[00119] Advantageously, the locking assemblies 810, 820,

830, 840 do not increase the overall height or width of the

base plate 110 of the jack 100 while creating a slide effect

for each locking bar 812.

[00120] According to one embodiment, the main hydraulic

lifting cylinders 271, 272, 273, 274 are arranged in a

straight or approximately straight row extending from the left

side 180 to the right side 170 of the base plate 110 of the jack 100 with the telescoping liner guide columns 261, 262 on either end (as shown in FIG. 24).

[00121] According to one embodiment, each of the main

hydraulic lifting cylinders 271, 272, 273, 274 may be another

type of actuator such as a pneumatic or electric actuator.

[00122] FIG. 26 is a front view illustrating one of the

compact spherical bearing cylinder mounts 410 shown in FIG. 24

in accordance with an embodiment of the application. FIG. 27

is a cross-sectional view thereof taken along line C-C in FIG.

26. And, FIG. 28 is a cross-sectional detail view illustrating

the installation of the compact spherical bearing cylinder

mounts 410, 420 in the main lifting assembly 200 shown in FIG.

24 taken along line A-A in FIG. 23.

[00123] According to one embodiment, each compact spherical

bearing cylinder mount 410, 420 may include: a female

spherical radius cup 411 having a flat outer surface for

mounting on a surface, such as the lower surface 212 of the

top plate 210, and a female spherical radius inner surface (or

bearing); a male spherical radius cup 412 having a male

spherical radius inner surface (or bearing) for mating with

the female spherical radius inner surface of the female

spherical radius cup 411 and a flat outer surface equipped

with a central thread 413 for coupling to a hydraulic cylinder

such as the piston rod end 276 of the third main hydraulic

lifting cylinder 273; and, bolts 414 (or other fasteners) for

loosely coupling the female spherical radius cup 411 to the

male spherical radius cup 412.

[00124] The purpose of the compact spherical bearing

cylinder mounts 410, 420 is to reduce mechanical side loading

on the rods of the main hydraulic lifting cylinders 273, 274.

The main lifting assembly 200 will typically move or flex when

loads are introduced thus causing an offset linear force on

the main hydraulic lifting cylinders 273, 274 and their rod

assemblies which may result in a hydraulic seal failure and

premature oil leakage. The bearings 411, 412 of each compact

spherical bearing cylinder mount 410, 420 mate together in a

manner similar to that of a ball and socket and allow for an

approximately 15 thousands of an inch offset load. The compact

spherical bearing cylinder mounts 410, 420 allow for a very

low profile (e.g., approximately one inch) mechanical link

between the main hydraulic lifting cylinders 273, 274 and the

top lifting plate 210. The loose bolting 414 of the female

spherical radius cup 411 to the male spherical radius cup 412

allows for a mechanical link between the hydraulic cylinders

273, 274 and the top plate 210 upon retraction or lowering as

well as upon extension or lifting.

[00125] According to one embodiment, the main lifting

assembly 200 may be operated as a stand alone lifting device.

[00126] FIG. 29 is a left side view illustrating the jack

100 of FIG. 1 positioned under the rear lifting point 1020 of

a truck 1000 in accordance with an embodiment of the

application. FIG. 30 is a rear view thereof. FIG. 31 is a left

side view illustrating the jack 100 of FIG. 1 positioned under

the front lifting point 1030 of a truck 1000 in accordance

with an embodiment of the application. FIG. 32 is a rear view

thereof.

[00127] In operation, the jack 100 with its top plate 210

(and intermediate plate 230) in the lowered position 1200 is

positioned under a lifting point (e.g., the rear lifting point

1020) of a truck 1000 by an operator using a remote control

unit. When positioned, the front and rear wheels 131, 132,

141, 142 of the jack 100 are retracted and the jack 100 is

ready for lifting. To lift the truck 1000, the upper surface

211 of the top plate 210 is brought into contact with the

lifting point 1020 by moving the top plate 210 to a partially

raised position (e.g., 1600) under control of the operator

using a remote control unit. When moving from the jack's

lowered position 1200 to its partially raised position 1600,

the piston rod of each main hydraulic lifting cylinder 271,

272, 273, 274 is urged out of its respective cylinder barrel

by fluid pressure causing the intermediate plate 230 and the

top plate 210 to be pushed upward to their respective

partially raised positions 1600, the telescoping linear guide

columns 261, 262 to be partially extended, and the rollers 814

of the locking bars 812 of each of the locking assemblies 810,

820, 830, 840 to be pulled up their respective ratchet racks

811 to engage respective notches 813 (e.g., the third notches)

to lock the top plate 210 and truck 1000 in place.

[00128] Similarly, when moving from the jack's partially

raised position 1600 to its raised position 2000, the piston

rod of each main hydraulic lifting cylinder 271, 272, 273, 274

is urged further out of its respective cylinder barrel by

fluid pressure causing the intermediate plate 230 and the top

plate 210 to be pushed further upward to their respective

raised positions 2000, the telescoping linear guide columns

261, 262 to be fully extended, and the rollers 814 of the

locking bars 812 of each of the locking assemblies 810, 820,

830, 840 to be pulled further up their respective ratchet

racks 811 to engage respective notches 813 (e.g., the fifth

notches) to the lock the top plate 210 and truck 1000 in

place.

[00129] After maintenance on the truck 1000 has been

performed, the truck 1000 is ready to be lowered. First, the

lock release hydraulic cylinder 852 of each lock release

assembly 850 is operated to move the lock release plate 851

from its retracted position 2510 to its extended position 2520

allowing the rollers 814 and their locking bars 812 to slide

downward over the notches 813 in their respective ratchet

racks 811. Second, when moving from the jack's raised position

1600 to its lowered position 1200, the piston rod of each main

hydraulic lifting cylinder 271, 272, 273, 274 is urged into

its respective cylinder barrel by fluid pressure causing the

intermediate plate 230 and the top plate 210 to be pulled

downward to their respective lowered positions 2000, the

telescoping linear guide columns 261, 262 to be fully

retracted, and the unlocked locking bars 812 of each of the

locking assemblies 281, 282, 283, 284 to be pushed down their

respective ratchet racks 811 to their lowered positions.

[00130] Thus, according to one embodiment, there is a

provided a jack 100, comprising: a top plate 210 adapted to

contact a load 1000; an intermediate plate 230 positioned

below the top plate 210, the intermediate plate 230 having a

channel 234 formed therein; a base plate 110 positioned below

the intermediate plate 230; a first pair of actuators 271, 272 coupled between the base plate 110 and the intermediate plate

230, one of the first pair of actuators 271, 272 positioned on

either side 233, 235 of the channel 234; and, a second pair of

actuators 273, 274 coupled between the channel 234 of the

intermediate plate 230 and the top plate 210; wherein the

first and second pairs of actuators 271, 272, 273, 274 are

operable to move the top plate 210 and the intermediate plate

230 between respective lowered positions (e.g., 1200) and

respective raised positions (e.g., 1600, 2000) to thereby

lower and raise the load 1000.

[00131] The above jack 100 may further include a pair of

telescoping linear guide columns 261, 262 coupled between the

base plate 110, intermediate plate 230, and top plate 210, one

of the pair of telescoping linear guide columns 261, 262

positioned on either side of the first pair of actuators 271,

272. The first and second pairs of actuators 271, 272, 273,

274 may be operable simultaneously. The load may be a truck

1000. The first and second pairs of actuators may be first and

second pairs of hydraulic cylinders 271, 272, 273, 274,

respectively. The first pair of actuators 271, 272, the second

pair of actuators 273, 274, and the pair of telescoping linear

guide columns 261, 262 may be arranged in a row.

[00132] The above jack 100 may further include at least one

locking assembly (e.g., 810) adapted to lock the top plate 210

in the raised position (e.g., 2000). The at least one locking

assembly 810 may include a locking bar 812 and a ratchet rack

811, the locking bar 812 having an upper end 819 and a lower

end 818, the locking bar 812 hinge mounted at the upper end

819 proximate to the top plate 210, the ratchet rack 811 inclining upward from the base plate 110 toward the top plate

210 and having at least one notch 813 formed therein, the at

least one notch 813 adapted to receive and lock the lower end

818 of the locking bar 812, and the lower end 818 of the

locking bar 812 being slidable up the ratchet rack 811 and

into the at least one notch 813 as the top plate 210 is moved

from the lowered position 1200 to the raised position 1600,

2000. The at least one locking assembly 810 may further

include a lock release assembly 850 adapted to unlock the top

plate 210 allowing the top plate 210 to be moved from the

raised position 1600, 2000 to the lowered position 1200. The

lock release assembly 850 may include a lock release plate 851

inclining upward from the base plate 110 toward the top plate

210, the lock release plate 851 moveable from a retracted

position 2510 to an extended position 2520 to urge the lower

end 818 of the locking bar 812 out of the at least one notch

813 allowing the lower end 818 of the locking bar 812 to slide

down the ratchet rack 811 and over the at least one notch 813

as the top plate 210 is moved from the raised position 1600,

2000 to the lowered position 1200. The locking bar 812, the

ratchet rack 811, and at least one notch 813 are mounted to be

visible from a location distant from the jack 100 and load

1000. The at least one locking assembly 810 may be four

locking assemblies 810, 820, 830, 840. The at least one notch

may be five notches 813.

[00133] The above jack 100 may further include a pair of

spherical radius bearing mounts 410, 420 adapted to couple the

second pair of actuators 273, 274 to the top plate 210,

respectively. The jack 100 may further include a pair of retractable front wheels 131, 132 mounted proximate to a front end 150 of the base plate 110. The pair of retractable front wheels 131, 132 may be hydraulically driven. The jack 100 may further include a pair of retractable and steerable rear wheels 141, 142 mounted proximate to a rear end 160 of the base plate 110.

[00134] The above jack 100 may further include an engine 710

mounted on the base plate 110 for providing power to

components of the jack 100. The jack 100 may further include a

remote control unit for controlling the jack 100 from a

location distant from the jack 100 and load 1000. And, the

jack 100 may further include a base lifting assembly 220

mounted to the base plate 110 within which the first pair of

actuators 271, 272 and the pair of telescoping linear guide

columns 261, 262 are mounted, an intermediate lifting assembly

240 within which the second pair of actuators 273, 274 are

mounted, and a top lifting assembly 250 on which the top plate

210 is mounted.

[00135] FIG. 33 is a front perspective view illustrating a

main lifting assembly 200 for the jack 100 of FIG. 1 with the

top plate 210 (and intermediate plate 230) shown in a lowered

position 1200 in accordance with another embodiment of the

application. FIG. 34 is a front view thereof. FIG. 35 is a top

view thereof. FIG. 36 is a left side view thereof. And, FIG.

37 is a cross-sectional view thereof taken along line A-A in

FIG. 36.

[00136] FIG. 38 is a partially exploded front perspective

view illustrating the main lifting assembly 200 of FIG. 33 in accordance with an embodiment of the application. FIG. 39 is a front view thereof. FIG. 40 is a left side view thereof. FIG.

41 is a cross-sectional view thereof taken along line B-B in

FIG.40. And, FIG. 42 is a fully exploded front perspective

view thereof.

[00137] According to one embodiment, the main lifting

assembly 200 may include: a base lifting assembly (or frame)

220 mounted on the upper surface 111 of the base plate 110; an

intermediate lifting assembly (or frame) 240 mounted over the

base lifting assembly 220 and coupled thereto; a top lifting

assembly (or frame) 250 mounted over the intermediate lifting

assembly 240 and coupled thereto; compact spherical bearing

cylinder mounts 410, 420; and, first, second, third, and

fourth locking assemblies 810, 820, 830, 840.

[00138] According to one embodiment, the base lifting

assembly (or frame) 220 may be mounted on the upper surface

111 of the base plate 110 and may have first and second main

hydraulic lifting cylinders 271, 272 mounted therein. Each of

the first and second main hydraulic lifting cylinders 271, 272

has a piston rod end 276 and a cylinder barrel end 275. The

cylinder barrel end 275 of each of the first and second main

hydraulic lifting cylinders 271, 272 may be mounted on the

upper surface 111 of the base plate 110.

[00139] According to one embodiment, the intermediate

lifting assembly 240 may have an intermediate plate 230 having

a lower surface 232 and an upper surface 231. The intermediate

plate 230 may have left and right lowered portions 2341, 2342

formed therein. The left and right portions 233, 235 of the intermediate plate 230 on either side of the left and right lowered portions 2341, 2342 are at the same level (or height) while the middle portion or left and right lowered portions 2341, 2342 of the intermediate plate 230 are at a lower level (or height). Alternatively, the left and right lowered portions 2341, 2342 may be a single lowered portion 234 similar to that shown in FIG. 24. The intermediate plate 230 may be positioned over and parallel or approximately parallel to the base plate 110. The lower surface 232 of the left and right portions 233, 235 of the intermediate plate 230 may be coupled to the piston rod ends 276 of the first and second main hydraulic lifting cylinders 271, 272 of the base lifting assembly 220, respectively, via respective compact spherical bearing mounts 410, 420. The upper surface 231 of the left and right lowered portions 2341, 2342 of the intermediate plate 230 may have third and fourth main hydraulic lifting cylinders 273, 274 mounted thereto, respectively. Each of the third and fourth main hydraulic lifting cylinders 273, 274 has a piston rod end 276 and a cylinder barrel end 275. The cylinder barrel end 275 of each of the third and fourth main hydraulic lifting cylinders 273, 274 may be mounted on the upper surface 231 of the left and right lowered portions 2341, 2342 of the intermediate plate 230, respectively.

[00140] Advantageously, by using an intermediate plate 230 having a lowered portion 234 or lowered portions 2341, 2342 formed therein, the overall height of the main lifting assembly 200 may be reduced.

[00141] According to one embodiment, the top lifting assembly 250 may have a top plate 210 having a lower surface

212 and an upper surface 211. The top plate 210 may be positioned over and parallel or approximately parallel to the intermediate plate 230. The lower surface 212 of the top plate 210 may be coupled to the piston rod end 276 of each of the third and fourth main hydraulic lifting cylinders 273, 274 of the intermediate lifting assembly 240 via respective compact spherical bearing mounts 410, 420. The upper surface 211 of the top plate 210 may be adapted for contacting the lifting points 1020, 1030 of a truck 1000 (or other load) either directly or via optional sliding adaptor blocks 6100, 6200 mounted to the upper surface 211 of the top plate 210 via an optional adaptor block mounting plate 5000 as described further below.

[00142] FIG. 43 is a front perspective view illustrating a main lifting assembly 200 for the jack 100 of FIG. 1 with the top plate 210 (and intermediate plate 230) shown in a lowered position 1200 and equipped with sliding adapter blocks 6100, 6200 and an adapter block mounting plate 5000 in accordance with another embodiment of the application. FIG. 44 is a front view thereof. FIG. 45 is a top view thereof. FIG. 46 is a left side view thereof. FIG. 47 is a partially exploded front perspective view illustrating the main lifting assembly 200 of FIG. 43 in accordance with an embodiment of the application. And, FIG. 48 is a front view thereof.

[00143] The upper surface 211 of the top plate 210 may be adapted for contacting the lifting points 1020, 1030 of a truck 1000 (or other load) via sliding adapter blocks 6100, 6200 mounted to the upper surface 211 of the top plate 210 via an adapter block mounting plate 5000.

[00144] The sliding adapter blocks 6100, 6200 are provided

to shift a heavy load (e.g., a 220 ton truck) 1000 while

preventing or reducing any misalignment or bending of the main

lifting assembly 200 of the jack 100 (e.g., misalignment or

bending with respect to the vertical axis of the main lifting

assembly 200 from front 150 to rear 160 (and/or from rear 160

to front 150) of the jack 100). This allows the four locking

bars 812 of the locking assemblies 810, 820, 830, 840 to

function smoothly and effectively and reduces or eliminates

top plate 210 or adapter block 6100, 6200 to load (e.g., truck

body) 1000 contact slippage.

[00145] According to one embodiment, the adapter block

mounting plate 5000 has an upper surface 5011 upon which one

or more adapter blocks 6100, 6200 are mounted. The lower

surface 5012 of the adapter block mounting plate 5000 is

attached to the upper surface of the top plate 210 of the main

lifting assembly 200. The adapter block mounting plate 5000

may have one or more mounting slots 5100, 5200 formed therein

for receiving and positioning respective adapter blocks 6100,

6200. The mounting slots 5100, 5200 may be positioned

proximate left and right ends of the mounting plate 5000,

respectively, and may extend longitudinally across a portion

of the mounting plate 5000. The mounting slots 5100, 5200

allow the upper surfaces (e.g., 6111) of the adapter blocks

6100, 6200 to be accurately positioned under the lifting

points 1020, 1030 of a truck 1000 (or other load).

[00146] FIG. 49 is a front perspective view illustrating one

of the sliding adapter blocks 6100 shown in FIG. 43 with the

top adapter plate 6110 thereof shown in a first, unloaded, or retracted position 7001 in accordance with an embodiment of the application. FIG. 50 is a rear perspective view thereof. FIG. 51 is a top view thereof. FIG. 52 is a front view thereof. FIG. 53 is a right side view thereof. And, FIG. 54 is a cross-sectional view thereof taken along line A-A in FIG. 52.

[00147] FIG. 55 is a bottom perspective view thereof with the top adapter plate 6110 thereof shown in second or rearward position 7002. FIG. 56 is a front perspective view thereof. FIG. 57 is a top view thereof. FIG. 58 is a front view thereof. FIG. 59 is a right side view thereof. And, FIG. 60 is a cross-sectional view thereof taken along line A-A in FIG. 58.

[00148] FIG. 61 is a bottom perspective view thereof with the top adapter plate 6110 thereof shown in a third or forward position 7003. FIG.62 is a front perspective view thereof. FIG. 63 is a top view thereof. FIG. 64 is a front view thereof. FIG. 65 is a right side view thereof. And, FIG. 66 is a cross-sectional view thereof taken along line A-A in FIG. 64.

[00149] FIG. 67 is an exploded perspective view illustrating one of the sliding adapter blocks 6100 shown in FIG. 43 in accordance with an embodiment of the application. FIG. 68 is bottom perspective view illustrating the top adapter plate 6110 of the sliding block adapter block 6100 of FIG. 67 in accordance with an embodiment of the application. FIG. 69 is a rear perspective view thereof. FIG. 70 is a top view thereof. FIG. 71 is a front view thereof. FIG. 72 is a right side view thereof. And, FIG. 73 is a cross-sectional view thereof taken along line A-A in FIG. 71.

[00150] FIG. 74 is bottom perspective view illustrating the

bottom adapter plate 6120 of the sliding block adapter block

6100 of FIG. 67 in accordance with an embodiment of the

application. FIG. 75 is a rear perspective view thereof. FIG.

76 is a top view thereof. FIG. 77 is a front view thereof.

FIG. 78 is a right side view thereof. And, FIG. 79 is a cross

sectional view thereof taken along line A-A in FIG. 77.

[00151] According to one embodiment, each sliding adapter

block (e.g., 6100) may include a top adapter plate 6110

slidably mounted over a bottom adapter plate 6120. The bottom

plate adapter plate 6120 is used for mounting the sliding

adapter block 6100 to the jack 100 (i.e., via the adapter

block mounting plate 5000) and remains stationary with respect

to the jack 100 during operation. A greased Nylatron TM sheet

6127 (or any similar nylon, plastic, nylon plastic, or

friction reducing material) may be positioned between the

lower surface 6112 of the top adapter plate 6110 and the upper

surface 6121 of the bottom adapter plate 6120 to improve

slippage (or reduce friction) between the top and bottom

plates 6110, 6120. The sheet 6127 also reduces wear between

the top and bottom adapter plates 6110, 6120. The top adapter

plate 6110 may be coupled to the bottom adapter plate 6120 by

first and second or left and right alignment rods 6150, 6160

which pass through respective holes 6131, 6141 formed in

respective first and second or left and right alignment blocks

6130, 6140 mounted on respective first and second or left and

right sides 6123, 6124 of the upper surface 6121 of the bottom adapter plate 6120. A rubber spring 6170 and a washer 6180 may be mounted on each end of each alignment rod 6150, 6160 and the top adapter plate 6110 may be attached (e.g., bolted, etc.) to the end of each alignment rod 6150, 6160 though respective mating holes 6190 formed in the front and rear sides 6113, 6114 of the top adapter plate 6110. The alignment rods 6150, 6160 slide within the holes 6131, 6141 formed in the alignment blocks 6130, 6140 allowing the top adapter plate 6110 to move or slip on the sheet 6127 over the bottom adapter plate 6120 and between the alignment blocks 6130, 6140.

[00152] As shown in FIG. 68, according to one embodiment, the lower surface 6112 of the top adapter plate 6110 extends downward to contact the greased Nylatron TM sheet 6127 on the upper surface 6121 of the lower adapter plate 6120. As shown in FIG. 74, the lower surface 6122 of the bottom adapter block 6120 may be equipped with an alignment extrusion 6125 which mates with a mounting slot (e.g., 5100) of the adapter block mounting plate 5000. As shown in FIG. 67, the top adapter plate 6110 may be equipped with handles 6195 for transport, ease of handling, and positioning. And, also as shown in FIG. 67, a slot 6117 may be formed in the upper surface 6111 of the top adaptor plate 6110 for the optional mounting of lifting adapters (not shown).

[00153] In operation, when the jack 100 begins lifting a load 1000, lateral loading (i.e., from front 150 to rear 160 (and/or from rear 160 to front 150) of the jack 100) causes the top adapter plate 6110 to slide over the bottom adapter plate 6120 from a first or unloaded or retracted position 7001 to either a second or rearward position 7002 or a third or forward position 7003 depending on the direction of the lateral loading. The sliding is facilitated by the greased Nylatron TM sheet 6127 positioned between the top and bottom adapter plates 6110, 6120. This sliding of the top adapter plate 6110 improves or maintains vertical or approximately vertical alignment of the main lifting assembly 200 below the load 1000 which improves the stability of the jack 100. The rubber springs 6170 function to center the top adapter plate 6110, maintain proportional linear force, and reduce the speed of lateral shifting of the top adapter plate 6110 over the bottom adaptor plate 6120. The washers 6180 provide a surface for the rubber springs 6170 to elastically deform during shifting of the top adapter plate 6110. The alignment blocks 6130, 6140, alignment rods 6150, 6160 align the top and bottom adapter plates 6110, 6120 making them function as one unit and allowing for the top adapter plate 6110 to shift smoothly when the jack 100 is under lateral loading.

[00154] Thus, according to another embodiment, there is provided a jack 100, comprising: a top plate 210 having at least one adapter block (e.g., 6100) mounted thereon and adapted to contact a load 100; an intermediate plate 230 positioned below the top plate 210; a base plate 110 positioned below the intermediate plate 230; a first pair of actuators 271, 272 coupled between the base plate 110 and the intermediate plate 230; and, a second pair of actuators 273, 274 coupled between respective lowered portions 2341, 2342 of the intermediate plate 230 and the top plate 210; wherein one of the first pair of actuators 271, 272 is positioned on the base plate 110 on either side of the respective lowered portions 2341, 2342 of the intermediate plate 230; wherein the first and second pairs of actuators 271, 272, 273, 274 are operable to move the top plate 210 and the intermediate plate

230 between respective lowered positions (e.g., 1200) and

respective raised positions (e.g., 1600, 2000) to thereby

lower and raise the load 1000; and, wherein a top adapter

plate 6110 of the at least one adapter block 6100 is operable

to slide between first 7001 and second positions 7002, 7003

on the top plate 210 as the load 1000 is raised and lowered to

thereby maintain alignment of the top, intermediate, and base

plates 210, 230, 110 below the load 1000.

[00155] In the above jack 100, the at least one adapter

block 6100 may include a bottom adapter plate 6120 attached to

the top plate 210 of the jack 100 and to which the top adapter

plate 6110 is slidably attached. The top adapter plate 6110

may be slidably attached to the bottom adapter plate 6120 by a

pair of alignment rods 6150, 6160 passing through respective

alignment blocks 6130, 6140 mounted on either side 6123, 6124

of the bottom adapter plate 6120, the alignment rods 6150,

6160 may be attached to front and rear ends 6113, 6114 of the

top adapter plate 6110 through respective rubber springs 6170.

The jack 100 may further include a plastic sheet 6127 mounted

between the top and bottom adapter plates 6110, 6120 to reduce

friction between the top and bottom adapter plates 6110, 6120.

The plastic sheet 6127 may be a greased nylon plastic sheet.

[00156] Also in the above jack 100, the first and second

pairs of actuators 271, 272, 273, 274 may be operable

simultaneously. The load 1000 may be a truck. The first and

second pairs of actuators 271, 272, 273, 274 may be first and second pairs of hydraulic cylinders, respectively. The first and second pairs of actuators 271, 272, 273, 274 may be arranged in a row.

[00157] The above jack 100 may further include at least one locking assembly (e.g., 810) adapted to lock the top plate 210 in the raised position (e.g., 2000). The at least one locking assembly 810 may include a locking bar 812 and a ratchet rack 811, the locking bar 812 having an upper end 819 and a lower end 818, the locking bar 812 hinge mounted at the upper end 819 proximate to the top plate 210, the ratchet rack 811 inclining upward from the base plate 110 toward the top plate 210 and having at least one notch 813 formed therein, the at least one notch 813 adapted to receive and lock the lower end 818 of the locking bar 812, and the lower end 818 of the locking bar 812 slidable up the ratchet rack 811 and into the at least one notch 813 as the top plate 210 is moved from the lowered position 1200 to the raised position 1600, 2000. The at least one locking assembly 810 may further include a lock release assembly 850 adapted to unlock the top plate 210 allowing the top plate 210 to be moved from the raised position 1600, 2000 to the lowered position 1200. The lock release assembly 850 may include a lock release plate 851 inclining upward from the base plate 110 toward the top plate 210, the lock release plate 851 moveable from a retracted position 2510 to an extended position 2520 to urge the lower end 818 of the locking bar 812 out of the at least one notch 813 allowing the lower end 818 of the locking bar 812 to slide down the ratchet rack 811 and over the at least one notch 813 as the top plate 210 is moved from the raised position 1600,

2000 to the lowered position 1200. The locking bar 812, the ratchet rack 811, and the at least one notch 813 are mounted to be visible (e.g., from a location distant from the jack 100 and load 1000). The at least one locking assembly 810 may be four locking assemblies 810, 820, 830, 840. The at least one notch 813 may be five notches.

[00158] The above jack 100 may further include respective pairs of spherical radius bearing mounts 410, 420 adapted to couple the first pair of actuators 271, 272 to the intermediate plate 230 and the second pair of actuators 273, 274 to the top plate 210. The jack 100 may further include: a pair of retractable front wheels 131, 132 mounted proximate to a front end 150 of the base plate 110, the pair of retractable front wheels 131, 132 may be hydraulically driven; a pair of retractable and steerable rear wheels 141, 142 mounted proximate to a rear end 160 of the base plate 110; and, an engine 710 mounted on the base plate 110 for providing power to components of the jack 100. The jack 100 may be remotely controllable (e.g., from a location distant from the jack 100 and load 1000 via a remote control unit). And, the jack 100 may further include a base lifting assembly 220 mounted to the base plate 110 within which the first pair of actuators 271, 272 are mounted, an intermediate lifting assembly 240 within which the second pair of actuators 273, 274 are mounted, and a top lifting assembly 250 on which the top plate 110 is mounted.

[00159] According to one embodiment, the compact spherical bearing cylinder mounts 410, 420 may be optional. According to one embodiment, one or more of: the first pair of actuators

271, 272 are directly (i.e., without intervening components,

linkage arms, etc.) coupled (e.g., one or more of attached,

connected, joined, bolted, welded, screwed, pinned, hinged,

etc.) between the base plate 110 and the intermediate plate

230; and, the second pair of actuators 273, 274 are directly

(i.e., without intervening components, linkage arms, etc.)

coupled (e.g., one or more of attached, connected, joined,

bolted, welded, screwed, pinned, hinged, etc.) between

respective lowered portions 2341, 2342 of the intermediate

plate 230 and the top plate 210. According to one embodiment,

one or more of: the first pair of actuators 271, 272 are

coupled perpendicularly or approximately perpendicularly

between the base plate 110 and the intermediate plate 230;

and, the second pair of actuators 273, 274 are coupled

perpendicularly or approximately perpendicularly between

respective lowered portions 2341, 2342 of the intermediate

plate 230 and the top plate 210. According to one embodiment,

the engine 710 may be an electric motor which may be powered

by the battery 740.

[00160] The above embodiments may contribute to an improved

telescoping jack 100 for lifting large capacity trucks 1000

and may provide one or more advantages. First, the jack 100

may be used on trucks made by multiple manufacturers such as

Caterpillar T M , KomatsuTM, and LiebherrTM and may accommodate

their proprietary specifications such as lifting points,

lifting methods, and height restrictions. Second, the jack 100

may be used on trucks of different physical sizes as it has a

width that may fit under the smallest truck but yet still may

balance the load of the largest truck. This reduces the need for two or more different jacks to handle differently sized trucks and hence provides for cost savings. Third, the jack

100 conforms to mine specific, country specific, and culture

specific safety protocols while accommodating any custom

aftermarket "add-ons" to the trucks provided by the above

mentioned truck manufacturers. Fourth, the jack 100 may be

used in high altitude applications. Fifth, the jack 100 fits

under the front of most trucks to reach the manufacturer's

certified lifting points. Sixth, the jack 100 has sufficient

working stroke to lift the front tires of a truck off the

ground. Seventh, the jack 100 requires only a single lift or

operation to lift the front or rear end of a truck. Eighth,

the jack 100 does not require the use of a separate safety

stand or other means required by existing "double lift" jacks.

Ninth, the jack 100 may complete a two-point lift in

approximately 10 minutes. Tenth, at approximately 7 tons and

with approximately 72 square feet of ground contact with the

wheels 131, 132, 141, 142 retracted, the jack 100 acts as

effective safety stand and requires no additional safety

stands. Eleventh, the jack 100 may be used as a multi-lifting

device for lifting skid plates, undercarriage components, and

the like. Twelfth, the jack 100 is user friendly and its

remote control reduces or eliminates the risk of operator

injury. Thirteenth, the jack 100 is designed to lift at O.E.M.

recommended truck lifting points 1020, 1030 and provides for

easy front and rear access under a truck 1000. Fourteenth,

using the jack 100 of the present application, a mining

operation improve per truck utilization by up to 815 hours in

a 48-month period. Fifteenth, the jack 100 has a low profile

with an overall collapsed height of approximately 33 inches while still achieving a very difficult linear lifting stroke of approximately 30 inches without using a scissor lift (the jack 100 not being of the scissor lift type) or telescoping hydraulic cylinders. And, sixteenth, the jack 100 has multiple seven pre-set position gravity activated secondary mechanical locking assemblies 810, 820, 830, 840 that provide a visual indication of load locking to an operator from a safe working distance.

[00161] The embodiments of the application described above

are intended to be exemplary only. Those skilled in this art

will understand that various modifications of detail may be

made to these embodiments, all of which come within the scope

of the application.

Claims (20)

WHAT IS CLAIMED IS:

1. A jack, comprising:

a top plate having at least one adapter block mounted

thereon and adapted to contact a load;

a base plate positioned below the top plate;

the top plate movable between a lowered position and a

raised position to thereby lower and raise the load; and,

at least one locking assembly adapted to lock the top

plate in the raised position; wherein the at least one

locking assembly includes a locking bar and a ratchet

rack, the locking bar having an upper end and a lower

end, the locking bar hinge mounted at the upper end

proximate to the top plate, the ratchet rack inclining

upward at an acute angle from the base plate toward the

top plate and having at least one notch formed therein,

the at least one notch adapted to receive and lock the

lower end of the locking bar, and the lower end of the

locking bar slidable up the ratchet rack and into the at

least one notch as the top plate is moved from the

lowered position to the raised position;

wherein the ratchet rack is stationarily attached to the

base plate; and,

wherein a top adapter plate of the at least one adapter

block is operable to slide between first and second

positions on the top plate as the load is raised and

lowered to thereby maintain alignment of the top and base

plates below the load.

2. The jack of claim 1, wherein the at least one locking

assembly further includes a lock release assembly adapted to

unlock the top plate allowing the top plate to be moved from

the raised position to the lowered position.

3. The jack of claim 2, wherein the lock release assembly

includes a lock release plate inclining upward from the base

plate toward the top plate, the lock release plate moveable

from a retracted position to an extended position to urge the

lower end of the locking bar out of the at least one notch

allowing the lower end of the locking bar to slide down the

ratchet rack and over the at least one notch as the top plate

is moved from the raised position to the lowered position.

4. The jack of claim 3, wherein the locking bar, the ratchet

rack, and the at least one notch are mounted to be visible.

5. The jack of claim 1, wherein the at least one locking

assembly is two locking assemblies.

6. The jack of claim 1, wherein the at least one notch is

three notches.

7. The jack of claim 1, further comprising a remote control

unit for remotely controlling operations of the jack.

8. The jack of claim 1, further comprising a pair of front

wheels mounted proximate to a front end of the base plate and

at least one rear wheel mounted proximate to a rear end of the

base plate.

9. The jack of claim 1, further comprising a battery mounted

on the base plate for providing power to components of the

jack.

10. The jack of claim 1, wherein the jack is remotely

controllable.

11. The jack of claim 1, wherein the load is a truck.

12. The jack of claim 1, wherein the at least one adapter

block includes a bottom adapter plate attached to the top

plate of the jack and to which the top adapter plate is

slidably attached; and, wherein the top adapter plate is

slidably attached to the bottom adapter plate by a pair of

alignment rods passing through respective alignment blocks

mounted on either side of the bottom adapter plate, the

alignment rods being attached to front and rear ends of the

top adapter plate through respective rubber springs.

13. A locking assembly for a jack, the jack having a top

plate having at least one adaptor block mounted thereon and

adapted to contact a load, a base plate positioned below the

top plate, and the top plate movable between a lowered

position and a raised position to lower and raise the load,

the locking assembly comprising:

a ratchet rack, the ratchet rack inclining upward at an

acute angle from the base plate toward the top plate and

having at least one notch formed therein; and, a locking bar, the locking bar having an upper end and a lower end, the locking bar hinge mounted at the upper end proximate to the top plate; wherein the at least one notch is adapted to receive and lock the lower end of the locking bar, the lower end of the locking bar slidable up the ratchet rack and into the at least one notch as the top plate is moved from the lowered position to the raised position to thereby lock the top plate in the raised position; and, wherein the racket rack is stationarily attached to the base plate.

14. The locking assembly of claim 13, further comprising a

lock release assembly adapted to unlock the top plate allowing

the top plate to be moved from the raised position to the

lowered position.

15. The locking assembly of Claim 14, wherein the lock

release assembly includes a lock release plate inclining

upward from the base plate toward the top plate, the lock

release plate moveable from a retracted position to an

extended position to urge the lower end of the locking bar out

of the at least one notch allowing the lower end of the

locking bar to slide down the ratchet rack and over the at

least one notch as the top plate is moved from the raised

position to the lowered position.

16. The locking assembly of claim 15, wherein the locking

bar, the ratchet rack, and the at least one notch are mounted

to be visible.

17. The locking assembly of claim 13, wherein the at least

one notch is three notches.

18. The locking assembly of claim 13, wherein the jack

includes at least two locking assemblies.

19. The locking assembly of claim 13, wherein the load is a

truck.

20. The locking assembly of claim 313wherein a top adapter

plate of the at least one adapter block is operable to slide

between first and second positions on the top plate as the

load is raised and lowered to thereby maintain alignment of

the top and base plates below the load; wherein the at least

one adapter block includes a bottom adapter plate attached to

the top plate of the jack and to which the top adapter plate

is slidably attached; and, wherein the top adapter plate is

slidably attached to the bottom adapter plate by a pair of

alignment rods passing through respective alignment blocks

mounted on either side of the bottom adapter plate, the

alignment rods being attached to front and rear ends of the

top adapter plate through respective rubber springs.