LIFTING AID FOR PLANAR MEMBERS

AUXILIAIRE DE LEVAGE POUR ELEMENTS PLANS

English Abstract

A lifting aid for lifting and supporting a ground engagement tool has an L-shaped cradle having a longitudinally extending base and back wall. A lifting yoke having at least two tubular arms is slideably connected to the L-shaped cradle through tubular sleeves which extend upward to a lifting point. The tubular arms have an upper portion, and a lower portion angled relative to the upper portion, for forming an inflection point inclined rearward toward the back wall. In a rest position, the inflection point is positioned adjacent the tubular sleeves leaving space for the tool. In a lifted position, the inflection point approaches the back wall for gripping the tool therebetween.

French Abstract

Un auxiliaire de levage destiné au levage et au support d'un outil d'engagement au sol est équipé d'un berceau en L pourvu d'une base longitudinale et d'une paroi arrière. Une fourche de levage munie d'au moins deux bras tubulaires est raccordée par glissement au berceau en L au moyen de manchons tubulaires se prolongeant vers le haut jusqu'à un point de levage. Les bras tubulaires comprennent une partie supérieure, et une partie inférieure oblique par rapport à la partie supérieure, pour former un endroit de flexion incliné en arrière, vers la paroi arrière. En position de repos, l'endroit de flexion est contigu aux manchons tubulaires, ce qui laisse de l'espace pour l'outil. En position d'élévation, l'endroit de flexion se rapproche de la paroi arrière pour saisir l'outil.

Claims

THE EMBODIMENTS OF THE INVENTION IN WHICH AN
EXCLUSIVE PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS
FOLLOWS:
1. A lifting aid for lifting and supporting a longitudinally extending
planar member comprising:
an L-shaped cradle having a longitudinally extending base and back
wall;
at least two substantially parallel tubular sleeves spaced apart at a
front edge of the base, a top end of each of the at least two sleeves inclined
rearward towards the back wall; and
a lifting yoke having at least two tubular arms slideably connected to
the L-shaped cradle through the tubular sleeves, the tubular arms extending
upwardly and connected to a lifting point, the tubular arms having an upper
portion
and a lower portion angled relative to the upper portion for forming an
inflection
point extending rearward toward the back wall,
wherein
in a rest position, the inflection point is positioned adjacent the tubular
sleeves for permitting the planar member to be positioned between the
inflection
point and the back wall, and
in a lifted position, the inflection point approaches the back wall for
gripping the planar member therebetween.
9

2. The lifting aid as described in claim 1 wherein the planar
member is a ground engagement tool.

Description

CA 02502259 2005-03-24
1 "LIFTING AID FOR PLANAR MEMBERS"
2
3 FIELD OF THE INVENTION
4 Embodiments of the present invention relate to accessories for use
with heavy equipment such as bulldozers and graders and the like and, more
6 particularly, to accessories which aid in replacement of cutting edges and
wear
7 plates or ground engagement tools (GETs) on said bulldozers, graders and the
like.
8
9 BACKGROUND OF THE INVENTION
Heavy equipment used for grading, mining and the like is typically fit
11 with a blade which has at least one replacement plate for improving a
cutting or
12 grading action of the blade and/or preventing wear of said blade. Often a
blade may
13 be fit with both a cutting edge and a wear plate fastened to the blade.
Such plates
14 are often referred to as ground engagement tools or GET.
As wear occurs, the GET is removed and replaced or rotated for use
16 on an opposing side. Typically, a GET may be 8-12 inches high and at least
8 feet
17 long and often weigh from about 500-600 pounds. During replacement, the GET
18 must be lifted to align holes in the GET with holes on the blade and held
in position
19 while the GET is secured, such as by bolts, to the blade. Due to the weight
and the
relatively sharp lower edge of the GET, lifting and supporting the GET is
difficult.
21 The difficulty is further enhanced by the fact that the blade is typically
at an angle
22 and the center of gravity of the GET is shifted when positioned adjacent to
the
23 blade.

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1 It is known to provide means for aiding in lifting and supporting a GET
2 for attachment to a blade.
3 US Patent 5,071,183 to Mc Dermott et al. describes an elongate bar
4 having brackets at each end of the bar in which a GET may be supported for
mounting to the blade. The bracket provides a fixed width slot in which the
GET is fit
6 and supported against a back of the bracket. A suspension member is
connected at
7 a center of the bar and is angled for maintaining the GET at the desired
angle when
8 suspended from a crane or the like.
9 US Patent 6,241,227 to Berdan et al. describes a cart configured to
support a GET at an angle suitable for attachment to a plow or grader blade.
The
11 frame and GET holder are moveable up and down relative to the ground for
lifting
12 the GET into pace adjacent the blade. The GET or GET and wear plate are
13 supported against the back of L-shaped cradles which are a fixed on the
frame at
14 the desired angle. A nut and bolt assembly aids in retaining the GET in an
upright
positioned supported against the wall of the cradle.
16 Clearly what is required is a lifting aid which is relatively inexpensive
17 to build and to operate and which can make use of existing on-site
equipment, if
18 possible, to assist in lifting and supporting a GET for removal and
replacement. Of
19 special importance is that the lifting aid safely and securely support the
GET to
prevent injury to workers during the process.
21
22
2

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1 SUMMARY OF THE INVENTION
2 A lifting aid for lifting and supporting a longitudinally extending planar
3 member, such as a ground engagement tool for a blade, comprises: an L-shaped
4 cradle having a longitudinally extending base and back wall; at least two
substantially parallel tubular sleeves spaced apart at a front edge of the
base, a top
6 end of each of the at least two sleeves inclined rearward towards the back
wall; and
7 a lifting yoke having at least two tubular arms slideably connected to the L-
shaped
8 cradle through the tubular sleeves, the tubular arms extending upwardly and
9 connected to a lifting point, the tubular arms having an upper portion and a
lower
portion angled relative to the upper portion for forming an inflection point
extending
11 rearward toward the back wall, wherein in a rest position, the inflection
point is
12 positioned adjacent the tubular sleeves for permitting the planar member to
be
13 positioned between the inflection point and the back wall, and in a lifted
position, the
14 inflection point approaches the back wall for gripping the planar member
therebetween.
16
3

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1 BRIEF DESCRIPTION OF THE DRAWINGS
2 Figure 1 is an exploded view of a GET and a blade prior to assembly;
3 Figures 2a, 2b and 2c are perspective, side and side views of a
4 reversible get for a blade such as a dozer blade;
Figures 3a and 3b are perspective and side views of a non-reversible
6 get for a blade such as a grader blade;
7 Figure 4 is a side or end view of one embodiment of the invention in a
8 rest position with dotted lines illustrating the lifted position;
9 Figure 5 is a side view of the embodiment of Fig. 4 in the lifted position
with a GET pinched or gripped therein;
11 Figures 6a - 6c are a side view, a front view and a front view with a
12 GET according to one embodiment of the invention;
13 Figure 7 is a perspective side view of the embodiment of Figs. 6b and
14 6c;
Figure 8 is a perspective front view of the embodiment of Fig 7;
16 Figure 9 is a side view of another embodiment having an inverted V
17 shaped yoke;
18 Figure 10 is a back view of the embodiment of Fig. 9;
19 Figure 11 is a front view of the embodiment of Fig. 9 illustrating the
embodiment in the rest position;
21 Figure 12 is a front view of the embodiment of Fig. 9 illustrating the
22 embodiment in the lifted position; and
4

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1 Figure 13 is a side tilted view of an embodiment illustrating an
2 indexing means connected to a bottom of the L-shaped cradle for removeably
3 positioning the tubular sleeves relative to the base of the cradle.
4
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
6 Having reference to Fig. la, a cutting edge, wear plate or the like,
7 commonly referred to as a ground engagement tool or GET 10, is shown spaced
8 apart from and in alignment with a blade 11 of a piece of equipment, such as
a
9 dozer or grader (not shown) to which the GET 10 is to be fastened. A
plurality of
holes 12 are formed in a top edge 13 of the GET 10 and co-operate with a
plurality
11 of holes 14 formed in the blade 11 for fastening the GET 10 to the blade
11,
12 typically using fasteners 15, such as bolts.
13 As shown in Figs. 2a, 2b and 2c and in the case of a conventional
14 GET 10 for a track dozer 16 (Fig. 2b), the holes 12 are formed at a center
17 of the
GET 10 and the GET 10 is formed having reversible edges 18. Less than %2 a
16 height of the GET 10 extends below the blade 11 when fastened thereto.
17 As shown in Figs. 3a and 3b, and in the case of a conventional GET
18 10 fora grader 19 (Fig. 3b), the holes 12 are formed offset from the center
17 of the
19 GET 10 and the GET 10 is not reversible. More than %2 the height of the GET
10
extends below the blade 11 when fastened thereto.
21 Having reference to Figs. 4 - 8, and in an embodiment of the
22 invention, a lifting aid 20 for supporting a longitudinally extending
planar member,
23 such as a GET 10, particularly during lifting and installation onto the
blade 11 of a
5

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1 dozer or grader 16,19, is shown. The lifting aid 20 comprises a
longitudinally
2 extending L-shaped cradle 21 having a base 22 and a back wall 23. At least
two
3 substantially parallel tubular sleeves 24 are spaced apart and affixed to a
front edge
4 25 of the base 22. The sleeves 24 are inclined inward or rearward toward the
back
wall 23 at a top end 26. A lifting member or yoke 27 is connected to the L-
shaped
6 cradle 21 through the tubular sleeves 24.
7 As shown in Figs. 6b, 6c, 7 and 8 and in one embodiment of the
8 invention, the lifting yoke 27 comprises a pair of tubular arms 28 and a
span
9 member 29 connected therebetween at a top end 30 of each of the tubular arms
28.
Further, a lifting point 31, such as a hole for engaging a hook extending from
a
11 crane boom (not shown), is formed at a center of the span member 29. The
lifting
12 point 31 is aligned with a center of the cradle 21 for supporting the GET
10 from
13 lateral movement once engaged in the cradle 21.
14 In an alternate embodiment, as shown in Figs. 9-13, the tubular arms
28 of the lifting yoke 27 extend upwards and towards each other for forming an
16 inverted V-shaped lifting yoke. The lifting point 31 is formed at an
intersection 32 at
17 the top end 30 of the tubular arms 28 and is typically a loop 33 welded
thereto for
18 engaging the crane hook (not shown).
19 As shown in Figs. 4, 5, 11 and 12 the tubular arms 28 of the lifting
yoke 27 slideably extend through the tubular sleeves 24 for connecting the
lifting
21 yoke 27 thereto. The sleeves 24 are of sufficient length to prevent binding
of the
22 tubular arms 28 therein. A stop 34 is formed at a lower end 35 of each of
the tubular
6

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1 arms 28 for preventing the arms 28 from leaving the tubular sleeves 24 once
2 engaged therein.
3 The tubular arms 28 further comprise a lower portion 36 and an upper
4 portion 37 which are angled relative to one another forming a point of
inflection 38
therebetween.
6 As shown in Figs. 4 and 11, in a rest position, the tubular arms 28 are
7 positioned having the lower portion 36 engaged in the tubular sleeves 24
with the
8 point of inflection 38 adjacent the sleeves 24 and spaced away from the back
wall
9 23 of the cradle 21 to permit the GET 10 to be positioned between the
tubular arms
28 and the back wall 23.
11 As shown in Figs. 5 and 12, as the lifting yoke 27 is lifted, such as by
12 a crane, the tubular arms 28 slide to move axially within the tubular
sleeves 24 to a
13 second gripping position wherein the point of inflection 38 is lifted and
approaches
14 the back wall 23 for pinching or gripping the GET 10 therebetween, Thus, as
the
lifting yoke 27 is actuated to lift the lifting aid 20 and the GET 10, the
tubular arms
16 28 act to grip the GET 10 in the cradle 21 and more securely retain the GET
10
17 therein.
18 Further, and preferably, the angle formed between the upper and
19 lower portions 36, 37 of the tubular arms 28 is sufficient to position the
center of
gravity of the lifting aid 20 and the GET 10 supported therein at an angle
21 substantially the same as the angle of the blade 11 to which the GET is to
be
22 attached. As a result, less manipulation of the GET 10 and the lifting aid
20 is
7

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1 required for an operator to successfully secure the GET 10 to the blade 11
resulting
2 in a safer operation.
3 Optionally, in the alternate embodiment, a transverse support member
4 40 may be connected between the tubular arms 28, spanning therebetween to
increase the structural rigidity and to further support the lifting yoke 27.
6 Having reference to Fig. 13 and in an embodiment of the invention,
7 the tubular sleeves 24 are connected to the base 22 of the cradle 21 through
8 indexing means 50 which permit a distance D, between the point of inflection
38 of
9 the tubular arms 28 and the back wall 23, to be changed to accommodate GET's
having different thicknesses.
11 In one embodiment, the indexing means 50 comprises attachment
12 plates 51 connected to an underside 52 of the base 22, adjacent each of the
tubular
13 sleeves 24, for removeably attaching the tubular sleeves 24 to the base 22.
Each of
14 the tubular sleeves 24 has a flange 53 connected thereto for connecting to
the
attachment plates 51. The attachment plates 51 have a plurality of holes 53
formed
16 therethrough at spaced intervals therealong for adjusting the positioning
of the
17 sleeves relative to the base 22 and thus, the distance of the inflection
point 38 from
18 the back wall 23.
19 Optionally, material can be removed from the back wall 23, such as by
holes 41 cut from the back wall 23, to reduce the weight of the lifting aid
20.
21
22
8

Representative Drawing