SHOVEL LIFTING SYSTEM AND METHOD

Abstract

A method of lifting a shovel having a car-body including endless tracks, and an upper part supported by the car-body, the method includes: disposing a rear lifting system under a rear section of the upper part; disposing a front central lifting system under a front section of the upper part, the front central lifting system having a width less than a distance between the endless tracks; and lifting the upper part of the shovel by applying a lifting force to the rear section of the upper part with the rear lifting system and by applying a lifting force to the front section of the upper part with the front central lifting system.

Description

TECHNICAL FIELD

The application relates to a lifting system and method for safely raising and disassembling in multiple parts a shovel or raise it as a whole above a ground while maintaining it leveled to the ground.

BACKGROUND

Routine maintenance often requires that heavy equipment such as mechanical shovels be raised in elevation. This allows maintenance crews to access the obstructed components of the heavy equipment so as to perform maintenance and repairs and saves time and effort by disassembling the upper part of the shovel from its lower tractor part, or by raising it as a whole.

For instance, a large hydraulic or electrical shovel has a lower car-body or tractor which uses continuous track motion to displace the shovel. In order to repair or perform maintenance on both of the upper part, also referred to as the house, and the lower part, also referred to as the car-body or tractor of the shovel, it would be desirable to access those components separately or at different height. Also, it is often required to separate the upper part from the car-body to perform maintenance on a pin, bushing, bearing or swing gears used to rotate the upper part relative to the lower part. This can be done by raising and/or disassembling the shovel in two parts.

SUMMARY

In one aspect, there is provided a method of lifting a shovel having a car-body including endless tracks, and an upper part supported by the car-body, the method comprising: disposing a rear lifting system under a rear section of the upper part; disposing a front central lifting system under a front section of the upper part, the front central lifting system having a width less than a distance between the endless tracks; and lifting the upper part of the shovel by applying a lifting force to the rear section of the upper part with the rear lifting system and by applying a lifting force to the front section of the upper part with the front central lifting system.

The method described above may include any of the following features, in any combinations.

In some embodiments, the disposing of the front central lifting system under the front section includes abutting the front central lifting system against pivot attachments of the upper part, the pivot attachments used to pivotally connect front attachments to the upper part.

In some embodiments, the front attachments include actuators pivotably connected to the pivot attachments for moving the front attachments, the method comprising disconnecting lower ends of the actuators of the front attachments from the pivot attachments.

In some embodiments, the method includes disconnecting front attachments from the upper part and mounting jigs to pivot attachments configured to pivotally connect front attachments to the upper part.

In some embodiments, the jigs include base plates and webs protruding transversally to the base plates, the method comprising: aligning the webs with apertures of pivot attachments; inserting pins into apertures of the webs and the apertures of the pivot attachments; and applying the lifting force to the front section of the upper part with the front central lifting system via the base plates of the jigs.

In some embodiments, the jigs are extender jigs each including sides interconnected via a bottom plate and a top plate and defining apertures, the sides protruding transversally from the bottom plate and the top plate, the method comprising: aligning the apertures of the sides of the jigs with apertures of the pivot attachments; inserting pins into the apertures of the sides and the apertures of the pivot attachments; and applying the lifting force to the front section of the upper part with the front central lifting system via the bottom plates of the jigs and counteracting a moment exerted by the lifting force on the jigs by abutting the bottom plates against a part of the upper part.

In some embodiments, the method further comprises rotating the car-body relative to the upper part until the endless tracks are extending transversally to the front attachments; after the lifting the upper part of the shovel, removing the car-body via a space defined between the rear lifting system and the front central lifting system.

In some embodiments, the front central lifting system includes a head, a foot for engaging a ground, and one or more actuators, the head engaged to the foot via the one or more actuators, the one or more actuators being extensible in length.

In some embodiments, a top beam is disposed over the head, the top beam having a width selected to overlap pivot attachments provided on the upper part and configured for connecting front attachments to the upper part, the method comprising abutting the top beam to the pivot attachments.

In some embodiments, the front central lifting system further includes outriggers having a collapsed configuration and an extended configuration, the outriggers defining feet, a distance between the feet increasing from the collapsed configuration to the extended configuration, the method comprising extending the outriggers from the collapsed configuration to the extended configuration.

In some embodiments, the lifting of the upper part of the shovel includes lifting the upper part while keeping a bucket of front attachments against a ground.

In another aspect, there is provided an assembly, comprising: a shovel having a car-body including endless tracks, and an upper part supported by the car-body; and a lifting system for lifting at least the upper part of the shovel, the lifting system having: a rear lifting system comprising first and second rear lifting units comprising one or more actuators, and disposed underneath a rear section of the upper part; and a front central lifting system located forward of the rear lifting system, the front central lifting system having a head engaged to pivot attachments of the upper part of the shovel, the pivot attachments configured for connecting front attachments to the upper part, a foot for engaging a ground, and one or more actuators engaged to both of the head and the foot, the one or more actuators operable to move the head relative to the foot.

The assembly described above may include any of the following features, in any combinations.

In some embodiments, a top beam is disposed over the head, the top beam abutting the pivot attachments of the upper part.

In some embodiments, the front central lifting system is intersected by a center line of the shovel.

In some embodiments, the front central lifting system has a width that is less than a distance between tracks of the car-body.

In some embodiments, the assembly includes jigs, each of the jigs mounted to a respective one of the pivot attachments, the head of the front central lifting system in abutment against the jigs.

In some embodiments, the jigs include base plates and webs protruding transversally to the base plates, the webs defining apertures, pins inserted to both of the apertures of the webs and into apertures of the pivot attachments, the base plate configured to be engaged by the front central lifting system.

In some embodiments, the jigs are extender jigs including sides interconnected via a bottom plate and a top plate and defining apertures, the sides protruding transversally from the bottom plate and the top plate, pins inserted through both of the apertures of the sides and into apertures of the pivot attachments, the front central lifting system abutting the bottom plates of the jigs, the bottom plates of the jigs configured for abutting a part of the upper part for counteracting a moment generated by the front central lifting system about the pins.

In some embodiments, the assembly includes outriggers having feet configured to increase a contact area between the front central lifting system and the ground, the outriggers have a collapsed configuration and an extended configuration, in the collapsed configuration, the feet are located proximate or overlap the foot, in the extended configuration, the feet may be spaced apart from one another and offset from the foot to increase the contact area with the ground.

In some embodiments, the assembly includes a beam disposed on top of the first and second rear lifting units and underneath a rear section of the upper part, the first and second rear lifting units spaced apart from one another by a distance greater than a width of the car-body.

BRIEF DESCRIPTION OF THE DRAWINGS

Reference is now made to the accompanying figures in which:

FIG. 1 is a side view of a shovel with a lifting mechanism engaged thereto in accordance with one embodiment and shown in a collapsed configuration;

FIG. 2 is a front view of the shovel and lifting mechanism of FIG. 1;

FIG. 3 is a front view of a front central lifting system of the lifting mechanism of FIG. 1;

FIG. 4 is a top view of the front central lifting system of FIG. 3;

FIG. 5 is an enlarged view of a portion of FIG. 2;

FIG. 6 is an enlarged view of a portion of FIG. 1;

FIG. 7 is a side view of a jig to be used with the front central lifting system of FIG. 3;

FIG. 8 is a front view of the jig of FIG. 7;

FIG. 9 is a side view of the shovel and lifting mechanism shown in an extended configuration;

FIG. 10 is a front view of the shovel and lifting mechanism in the extended configuration;

FIG. 11 is a side view of a shovel in accordance with another embodiment with a lifting mechanism;

FIG. 12 is a side view of a shovel in accordance with another embodiment with a lifting mechanism shown in a collapsed configuration;

FIG. 13 is a top view of an extender jig to be used with the lifting mechanism of FIG. 12;

FIG. 14 is a side view of the shovel and lifting mechanism of FIG. 12 shown in an extended configuration; and

FIG. 15 is a flowchart illustrating steps of a method of lifting a shovel.

DETAILED DESCRIPTION

There is described herein an apparatus and a method to lift or raise heavy machinery in whole or in parts. The apparatus coordinates the lifting of the heavy machinery so that it can be raised with respect to a ground surface. In so doing, the apparatus provides clearance so that vehicles and maintenance crews are able to access the obstructed ends of the heavy machinery and suspends the heavy machinery at an elevation while the maintenance operation is being performed.

As will be seen hereinafter, the apparatus and method are particularly useful for safely lifting heavy machinery, such as hydraulic or electrical shovels. FIG. 1 illustrates one example of such a shovel 10. The shovel 10 generally comprises an upper part 11 secured to a lower part 12. The upper part 11 may include motorization of the shovel 10. The lower part 12 comprises a car-body 13 having a side frame on each side. Each of the side frames have rollers which turn endless tracks 14 or treads to displace the shovel on a ground surface. The endless tracks 14 may be replaced by wheels in some embodiments. A rolling circle 15 is secured between the upper part 11 and the lower part 12 to allow the upper part 11 to revolve 360 degrees around a central axis A1 of the shovel 10 in either direction, clockwise or counterclockwise, and relative to the car-body 13. In the front of the upper part 11 are mounted a front attachments 20, which usually consist of a boom 21 pivotably mounted to the upper part 11, an arm 22 pivotably mounted to the boom 21, and a bucket 23 pivotably mounted to the arm 22. Boom cylinders 24 (shown in FIG. 11), arm cylinder(s) 25, and bucket cylinder(s) 26 are used to control movements of the front attachments 20. These cylinders may be, for instance, hydraulic actuators or any other suitable actuators. At the back, the shovel 10 is provided with a counterweight including a counterweight supporting frame 16 and counterweight slabs 17.

It will be appreciated that the principle of the present disclosure applies to electrical shovels, to hydraulic shovels, or to any other propulsion type shovels.

The boom cylinders 24 are removed from FIG. 1. The boom cylinders 24 are pivotably mounted to pivot attachments 27 defined by the upper part 11 of the shovel 10. The pivot attachments 27 may be two brackets each defining a hole for receiving a pin. The pins are received through the holes of the pivot attachments 27 and through holes defined at ends of the boom cylinders 24. In other embodiments, the boom cylinders 24 may remain in place or disconnected only from one of their ends.

At regular intervals, the shovel 10 may need to be lifted as a whole or the upper part 11 separated from the lower part 12 for servicing purposes of their components. For instance, the rollers of the car-body 13 need to be replaced at regular intervals. Similarly, the side frames of the car-body 13 eventually also need repairs or replacement. This type of maintenance requires a lot of time and effort and in doing so, there is a great incentive to be able to lift or separate the shovel 10 in a safe and easy manner. While it is possible to do so with lifts using large capacity hydraulic jacks, there is always room for improvement.

Still referring to FIG. 1, in the embodiment shown, a lifting system is used for lifting the upper part 11 relative to the car-body 13 is shown. The lifting system includes a rear lifting system 30 and a front central lifting system 40.

As shown in FIG. 2, the rear lifting system 30 includes a first rear lifting unit 31 and a second rear lifting unit 32. A beam 33 interconnects the first rear lifting unit 31 and the second rear lifting unit 32. Each of the first and second rear lifting units 31, 32 include a foot 34 to be disposed against a ground. The foot 34 may be laid against a crane mat 35; said crane mat 35 acting as an interface between the foot 34 and the ground to provide additional height required to remove the car-body 13 along with the side frames and tracks 14 from underneath the rear beam 33. The first and second rear lifting units 31, 32 may each include one or more cylinders 36, such as hydraulic actuators, linear actuators, or any suitable actuators known in the art. The cylinders 36 are operable to extend their lengths between a collapsed configuration (FIG. 2) and an extended configuration (FIG. 9).

As shown in FIG. 1, the beam 33 (FIG. 2) is in abutment against a rear section of the upper part 11. Upon powering the cylinders 36 of the first and second rear lifting units 31, 32, the beam 33 is lifted such that a distance between the beam 33 and the ground is increased. In so doing, the left and right lifting units 31, 32 exert a lifting force on the beam 33, which itself transfers the lifting force to the rear section of the upper part 11 to lift the upper part 11. The weight of the rear section is thus transmitted to the ground via the feet 34, and crane mats 35 in some embodiments. In other embodiments, the beam 33 may be omitted. In such a case, the rear lifting units 31 and 32 may be positioned closer apart and in abutment against a rear section of the upper part 11.

However, a front section of the upper part 11 may also require lifting. The front central lifting system 40 is used for this purpose. The front central lifting system 40 does not require a beam that spans a distance greater than a width of the shovel 10. The expression “width” implies a dimension in a direction being perpendicular to a direction of travel of the shovel 10. The width is thus transverse to the two tracks 14 in the embodiment shown in FIG. 2. Hence, the front central lifting system 40 is located entirely between the side-frames of the lower part 12. More specifically, the front central lifting system 40 is entirely contained between the tracks 14 of the car-body 13. A width of the front central lifting system 40 is thus less than a distance between the two tracks 14 of the car-body 13.

Referring to FIG. 3, the front central lifting system 40 is shown and described in greater detail. The front central lifting system 40 includes a head 41, a foot 42, one or more cylinders 43, two cylinders 43 in this embodiment, but more or less may be used. The cylinders 43 may be hydraulic cylinders or any other suitable actuators known in the art. The head 41 is movable vertically towards and away from a ground and relative to the foot 42 along direction denoted by arrow D1. The cylinders 43 are thus engaged to both of the head 41 and the foot 42.

In the embodiment shown, the front central lifting system 40 includes a top beam 44 disposed over the head 41. A cross-section of the top beam 44 may define an inverted U-shape to fit over a top portion of the head 41. Other shapes of the top beam 44 are contemplated. The top beam 44 has a width less than a distance between the tracks 14 of the car-body 13. The width of the top beam 44 has a length selected to overlap both pivot attachments 27 (FIGS. 1, 5) of the upper part 11. Hence, in this configuration, the front central lifting system 40 exerts a force on the pivot attachments 27 for lifting the front of shovel 10. The top beam 44 may be secured to the head 41 via dowels or any other suitable securing means (e.g., fasteners, clips, etc). In some embodiments, the top beam 44 may be omitted if a width of the head 41 is sufficient to simultaneously overlap both pivot attachments 27.

In some embodiments, a plate 49, such as a steel plate, may be disposed underneath the foot 42 of the front central lifting system 40 to better distribute a weight of the upper part 11. The plate 49 may be 10 feet by 20 feet and 2 inches thick, but other dimensions are contemplated. It may be square, rectangular, or any other suitable shape and made of any suitable material.

Referring now to FIG. 4, in the embodiment shown, the front central lifting system 40 includes outriggers, more particularly, first and second outriggers 45, 46 spaced apart from one another about a width of the front central lifting system 40. The first and second outriggers 45, 46 are used to better distribute a weight on the ground. The first and second outriggers 45, 46 therefore cooperate with the foot 42 to define a contact area between the front central lifting system 40 and the ground. The first and second outriggers 45, 46 each include longitudinal beams 47 extending about a length parallel to a direction of travel of the shovel 10. At distal ends of the longitudinal beams 47 are provided feet 48, four in this embodiment, to contact the ground, directly or via crane mats. The first and second outriggers 45, 46 may be telescopic. More specifically, the longitudinal beams 47 may be telescopic. Hence, the first and second outriggers 45, 46 may be moved from a collapsed configuration to an extended configuration. In the collapsed configuration, the feet 48 may be located proximate or overlap the foot 42. In the extended configuration, which is depicted in FIG. 4, the feet 48 may be spaced apart from one another and offset from the foot 42 to increase a contact area with the ground.

Referring to FIGS. 6-8, in the embodiment shown, the pivot attachments 27 of the upper part 11 of the shovel 10 may not provide a sufficiently large abutment face for the top beam 44 of the front central lifting system 40. Hence, in the disclosed embodiment, jigs 50 are used as an interface between the pivot attachments 27 and the top beam 44. Each of the jigs 50 includes a web 51 protruding transversally from a base plate 52. The web 51 is secured to the base plate 52. The web 51 vertically protrudes from the base plate 52. The web 51 defines an aperture 51A for receiving a pin 53 for pivotably connecting the jigs 50 to the pivot attachments 27. Each of the pivot attachments 27 may thus receive a web 51 of a respective one of the jigs 50. There may be more than one web per jig 50 used in some embodiments. The jigs 50 may therefore define a U-shape, reverse T-Shape or H-Shape as required. The jigs 50 may be made of metal and have a stiffness selected to ensure that the jigs 50 are able to withstand the heavy loads they are subjected to. The base plates 52 of the jigs 50 are in abutment against the top beam 44 of the front central lifting system 40. In some embodiments, shim plates 55 may be provided between the base plates 52 and the top beam 44 of the front central lifting system 40. In some embodiments, the front jigs 50 may have a locking system to block rotation of the front jigs 50 about the pins 53.

Referring now to FIGS. 9-10, the front central lifting system 40 and the rear lifting system 30 are shown in their extended configuration. In this configuration, there is sufficient clearance between the upper part 11 of the shovel 10 and the ground to move the car-body 13 away therefrom. In this case, the car-body 13 may be moved towards a rear of the reminder of shovel 10 and may pass underneath the beam 33 and between the first and second lifting units 31, 32. It may not be possible to remove the car-body 13 towards a front of the shovel 10 since the front central lifting system 40 blocks the way.

As illustrated, in this configuration, the boom cylinders 24 (shown in FIG. 11) are removed from the pivot attachments 27. This is typically when required to attach the jigs 50 to the pivot attachments 27. Therefore, the bucket 23 may be laid on a ground, or on a crane mat, during the lifting of the shovel 10. As the shovel 10 is lifted upward away from the ground, the boom 21 may rotate clockwise (as viewed in FIG. 9) relative to the upper part 11. It may therefore not be required to support the bucket 23 at a height above the ground during the lifting of the shovel 10. Hence, at least a portion of the weight of the front attachments 20 may not need to be supported by the lifting mechanism. In some embodiments, the front attachments 20, including the boom 21, the arm 22, and the bucket 23, may be totally or partially removed from the shovel 10.

In some embodiments, it may be desired to lift the shovel 10 without separating the lower part 12 from the upper part 11. In this case, the lifting mechanism may be able to lift an entirety of the shovel 10 including the car-body 13. Smaller lifting point(s) (not shown) may be used underneath the car-body 13 to achieve this function. In such case, the front central lifting system 40 may be omitted.

Referring to FIG. 11, a shovel in accordance with another embodiment is shown at 110. For the sake of conciseness, only features differing from the shovel 10 of FIG. 1 are described below.

In this embodiment, the pivot attachments 127 define an abutment face large enough for the top beam 44 of the front central lifting system 40. Therefore, the jigs 50 may be omitted in this configuration of the shovel 110. Hence, the lifting of the shovel 110 may be carried by keeping the boom cylinders 24 mounted to the pivot attachments 127. It may not be required to disconnect the boom cylinders 24 from the pivot attachments 127. Time savings may thus be obtained. To permit the boom 21 to rotate during the lifting, the boom cylinders 24 may be configured in a floating mode in which it may expand and contract without resistance.

Referring to FIGS. 12-14, a shovel in accordance with another embodiment is shown at 210. For the sake of conciseness, only features differing from the shovel 10 of FIG. 1 are described below.

In the embodiment shown, extender jigs 150 are engaged to the pivot attachments 27 and extends in abutment with the front central lifting system 40. The extender jigs 150 are used to provide enough clearance to laterally move the car-body 13 relative to the upper part 11. As shown in FIG. 13, the extender jigs 150 include two sides 151 spaced apart from one another a sufficient distance to be inserted in the pivot attachments 27. The two sides 151 are interconnected via a bottom plate 152 and a top plate 153. The two sides 151 define each an aperture 151A to receive the pin therein to pivotably connect the extender jigs 150 to the pivot attachments 27.

As shown in FIG. 12, a first end section 152A of the bottom plate 152 is used to abut the front central lifting system 40 whereas the extender jigs 150 counteracts a moment created by the front central lifting system 40 by having a second end section 152B of the bottom plate 152 abutting against a part of the upper part 11. Thus, the length of the extender jigs 150 is selected to ensure that a position of the front central lifting system 40 is sufficiently spaced apart from the car-body 13 to allow its removal from a space between the front and rear lifting systems 30, 40. In other words, this allows the front central lifting system 40 to exert a force at a distance sufficient to allow the removal of the car-body 13 laterally, between the rear and front lifting systems 30, 40, which may be preferable in some situations. In such case, the car-body 13 removal is not performed toward the rear lifting system 30. For that reason, the rear beam 33 may be omitted from the rear lifting system 30 and the rear lifting units 31 and 32 positioned closer apart and in abutment against a rear section of the upper part 11 still without interfering with the removal of the car-body 13.

Referring now to FIG. 15, a method of lifting a shovel is shown at 1500. The method 1500 includes disposing the rear lifting system 30 under a rear section of the upper part 11 at 1502; disposing the front central lifting system 40 under a front section of the upper part 11 at 1504. The front central lifting system 40 has a width smaller than a distance between the endless tracks 14 of the lower part 12. The width of the front central lifting system 40 may correspond to at most the distance between the endless tracks 14. In other words, the front central lifting system 40 is located inside a width smaller than the distance between the endless tracks 14. The method 1500 then includes lifting the upper part 11 of the shovel 10, 110 by applying a lifting force to the rear section of the upper part 11 with the rear lifting system 30 and by applying a lifting force to the front section of the upper part 11 with the front central lifting system 40 at 1506.

The applying of the lifting force to the front section of the upper part 11 includes transferring a load to a ground via a foot of the front central lifting system 40; the foot intersecting a centerline of the shovel 10, 110. The disposing of the front central lifting system 40 under the front section includes abutting the front central lifting system 40 against the pivot attachments 27 of the upper part 11.

In some embodiments, it may be required to disconnect lower ends of the boom cylinders 24 (i.e., actuators) of the front attachments 20 from the pivot attachments 27. Then, the jigs 50, 150 may be mounted to the pivot attachments 27. The front central lifting system 40 is thus abutted against the jigs 50, 150. The method 1500 may include abutting the top beam 44 against the pivot attachments 27. The top beam 44 may be abutted directly against the pivot attachments or to the jigs 50, 150. In some embodiments, the top beam 44 may be abutted against the shim plates 55.

As explained with reference to FIGS. 7-8, each of the jigs 50 includes a base plate 52 and a web 51. The method 1500 includes, for each of the jigs 50, aligning the aperture 51A of the web 51 with apertures of a respective one of the pivot attachments 27; inserting the pin 53 into the aperture 51A of the web 51 and the apertures of the pivot attachments 27; and applying the lifting force to the front section of the upper part 11 with the front central lifting system 40 via the base plates 52 of the jigs 50.

In an alternate embodiment, and as explained with reference to FIG. 12, the jigs are extender jigs 150 each including sides 151, interconnected via the bottom plate 151 and the top plate 152 and defining apertures 151A. The method 1500 may include aligning the apertures 151A of the sides 151 with the apertures of the pivot attachments 27; inserting the pins 53 into the apertures 151A of the sides 151 and the apertures of the pivot attachments 27; and applying the lifting force to the front section of the upper part 11 with the front central lifting system 40 via the jigs 150.

In this embodiment, the method 1500 further includes rotating the car-body 13 relative to the upper part 11 until the endless tracks 14 are extending transversally to the front attachments 20; and after the lifting the upper part 11 of the shovel 10, removing the car-body 13 via a space defined between the rear lifting system 30 and the front central lifting system 40. In other words, the car-body 13 may be removed along a direction being transversal to a distance between the front and rear lifting systems. Removing the car-body 13 laterally as such may greatly facilitate maintenance and reassembly of the car-body 13 to the upper part 11.

The method 1500 may further extending the first and second outriggers 45, 46 from the collapsed configuration to the extended configuration. The feet 48 of the outriggers may be laid against the ground or against crane mats. The lifting of the upper part 11 of the shovel 10, 110 may include lifting the upper part 11 while keeping the bucket 23 of the front attachments 20 against a ground.

The front central lifting system 40 may permit to increase safety during the lifting of the shovel 10, 110, may reduce a time required by maintenance personnel to perform the lifting of the shovel, may require less parts, may be easier to setup, and so on.

Typically, lifting the front portion of the upper part 11 required to: retract the arm 22 and lifting the boom 21 to seat the bucket 23 on a bucket stand; install pins in the jigs and secure them; disconnect all command controls and bump test; installing a sling between the bucket 23 and the arm 22; secure the boom cylinders 24 with attachment to the boom 21; remove bottom pins of the boom cylinders 24; retract the boom cylinders 24; readjust attachment of the boom cylinders 24 to provide clearance for the jigs; install the jigs and lock them with the boom cylinder pins; secure the jigs with another attachment; move a front beam, which has a length greater than a width of the shovel 10, under the jigs and raise the beam to abut the jigs; align and extend the boom cylinders 24 to reach the top of the jigs; remove the attachment listed above; raise the boom 21 and remove the bucket stand; and lower down the bucket 23. To install the jigs, when required, the boom cylinders 24 have to be removed with a crane and the bottom pins of the boom cylinders 24 are removed and the boom cylinders 24 are attached to the boom 21 or to the boom cylinders 24 with an attachment. Then, the jigs may be installed. The above procedure is long and complicated. In some cases, employees do not follow the instructions. Errors may thus follow. This may be dangerous in some cases.

As one can appreciate, the disclosed front central lifting mechanism 40 is much simpler to use and does not require all of the above steps. For instance, the disclosed method and front central lifting mechanism 40 do not require to reconnect the boom cylinders 24 to the jigs 50, 150 if they are dismounted from the pivot attachments 27. Thus, if the jigs 50, 150 are not required, the boom cylinders 24 may remain connected to the pivot attachments 27. If the jigs 50, 150 are required, the boom cylinders 24 are disconnected from the pivot attachments 27 and do not need to be attached to the jigs 50, 150. The front central lifting mechanism 40 is simply disposed under the front portion of the upper part 11 and aligned with the pivot attachments 27, 127. In some cases, the jigs 50,150 may be installed as described above. For lifting, the front central lifting system 40 is powered such that the cylinder(s) increase in length to abut the head against the jigs 50,150 or against the pivot attachments 27 to lift the upper part 11 from the ground.

It is noted that various connections are set forth between elements in the preceding description and in the drawings. It is noted that these connections are general and, unless specified otherwise, may be direct or indirect and that this specification is not intended to be limiting in this respect. A coupling between two or more entities may refer to a direct connection or an indirect connection. An indirect connection may incorporate one or more intervening entities. The term “connected” or “coupled to” may therefore include both direct coupling (in which two elements that are coupled to each other contact each other) and indirect coupling (in which at least one additional element is located between the two elements).

It is further noted that various method or process steps for embodiments of the present disclosure are described in the following description and drawings. The description may present the method and/or process steps as a particular sequence. However, to the extent that the method or process does not rely on the particular order of steps set forth herein, the method or process should not be limited to the particular sequence of steps described. As one of ordinary skill in the art would appreciate, other sequences of steps may be possible. Therefore, the particular order of the steps set forth in the description should not be construed as a limitation.

Furthermore, no element, component, or method step in the present disclosure is intended to be dedicated to the public regardless of whether the element, component, or method step is explicitly recited in the claims. As used herein, the terms “comprises”, “comprising”, or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

While various aspects of the present disclosure have been disclosed, it will be apparent to those of ordinary skill in the art that many more embodiments and implementations are possible within the scope of the present disclosure. For example, the present disclosure as described herein includes several aspects and embodiments that include particular features. Although these particular features may be described individually, it is within the scope of the present disclosure that some or all of these features may be combined with any one of the aspects and remain within the scope of the present disclosure. References to “various embodiments,” “one embodiment,” “an embodiment,” “an example embodiment,” etc., indicate that the embodiment described may include a particular feature, structure, or characteristic, but every embodiment may not necessarily include the particular features, structure, or characteristic. Moreover, such phrases are not necessarily referring to the same embodiment. The use of the indefinite article “a” as used herein with reference to a particular element is intended to encompass “one or more” such elements, and similarly the use of the definite article “the” in reference to a particular element is not intended to exclude the possibility that multiple of such elements may be present.

The embodiments described in this document provide non-limiting examples of possible implementations of the present technology. Upon review of the present disclosure, a person of ordinary skill in the art will recognize that changes may be made to the embodiments described herein without departing from the scope of the present technology. Yet further modifications could be implemented by a person of ordinary skill in the art in view of the present disclosure, which modifications would be within the scope of the present technology.

Claims

1. A method of lifting a shovel having a car-body including endless tracks, and an upper part supported by the car-body, the method comprising: disposing a rear lifting system under a rear section of the upper part;disposing a front central lifting system under a front section of the upper part, the front central lifting system having a width less than a distance between the endless tracks; andlifting the upper part of the shovel by applying a lifting force to the rear section of the upper part with the rear lifting system and by applying a lifting force to the front section of the upper part with the front central lifting system.

2. The method of claim 1, wherein the disposing of the front central lifting system under the front section includes abutting the front central lifting system against pivot attachments of the upper part, the pivot attachments used to pivotally connect front attachments to the upper part.

3. The method of claim 2, wherein the front attachments include actuators pivotably connected to the pivot attachments for moving the front attachments, the method comprising disconnecting lower ends of the actuators of the front attachments from the pivot attachments.

4. The method of claim 1, comprising disconnecting front attachments from the upper part and mounting jigs to pivot attachments configured to pivotally connect front attachments to the upper part.

5. The method of claim 4, wherein the jigs include base plates and webs protruding transversally to the base plates, the method comprising: aligning the webs with apertures of pivot attachments;inserting pins into apertures of the webs and the apertures of the pivot attachments; andapplying the lifting force to the front section of the upper part with the front central lifting system via the base plates of the jigs.

6. The method of claim 4, wherein the jigs are extender jigs each including sides interconnected via a bottom plate and a top plate and defining apertures, the sides protruding transversally from the bottom plate and the top plate, the method comprising: aligning the apertures of the sides of the jigs with apertures of the pivot attachments;inserting pins into the apertures of the sides and the apertures of the pivot attachments; andapplying the lifting force to the front section of the upper part with the front central lifting system via the bottom plates of the jigs and counteracting a moment exerted by the lifting force on the jigs by abutting the bottom plates against a part of the upper part.

7. The method of claim 6, further comprising: rotating the car-body relative to the upper part until the endless tracks are extending transversally to the front attachments;after the lifting the upper part of the shovel, removing the car-body via a space defined between the rear lifting system and the front central lifting system.

8. The method of claim 1, wherein the front central lifting system includes a head, a foot for engaging a ground, and one or more actuators, the head engaged to the foot via the one or more actuators, the one or more actuators being extensible in length.

9. The method of claim 8, comprising a top beam disposed over the head, the top beam having a width selected to overlap pivot attachments provided on the upper part and configured for connecting front attachments to the upper part, the method comprising abutting the top beam to the pivot attachments.

10. The method of claim 8, wherein the front central lifting system further includes outriggers having a collapsed configuration and an extended configuration, the outriggers defining feet, a distance between the feet increasing from the collapsed configuration to the extended configuration, the method comprising extending the outriggers from the collapsed configuration to the extended configuration.

11. The method of claim 1, wherein the lifting of the upper part of the shovel includes lifting the upper part while keeping a bucket of front attachments against a ground.

12. An assembly, comprising: a shovel having a car-body including endless tracks, and an upper part supported by the car-body; anda lifting system for lifting at least the upper part of the shovel, the lifting system having: a rear lifting system comprising first and second rear lifting units comprising one or more actuators, and disposed underneath a rear section of the upper part; anda front central lifting system located forward of the rear lifting system, the front central lifting system having a head engaged to pivot attachments of the upper part of the shovel, the pivot attachments configured for connecting front attachments to the upper part, a foot for engaging a ground, and one or more actuators engaged to both of the head and the foot, the one or more actuators operable to move the head relative to the foot.

13. The assembly of claim 12, comprising a top beam disposed over the head, the top beam abutting the pivot attachments of the upper part.

14. The assembly of claim 12, wherein the front central lifting system is intersected by a center line of the shovel.

15. The assembly of claim 12, wherein the front central lifting system has a width that is less than a distance between tracks of the car-body.

16. The assembly of claim 12, comprising jigs, each of the jigs mounted to a respective one of the pivot attachments, the head of the front central lifting system in abutment against the jigs.

17. The assembly of claim 16, wherein the jigs include base plates and webs protruding transversally to the base plates, the webs defining apertures, pins inserted to both of the apertures of the webs and into apertures of the pivot attachments, the base plate configured to be engaged by the front central lifting system.

18. The assembly of claim 16, wherein the jigs are extender jigs including sides interconnected via a bottom plate and a top plate and defining apertures, the sides protruding transversally from the bottom plate and the top plate, pins inserted through both of the apertures of the sides and into apertures of the pivot attachments, the front central lifting system abutting the bottom plates of the jigs, the bottom plates of the jigs configured for abutting a part of the upper part for counteracting a moment generated by the front central lifting system about the pins.

19. The assembly of claim 12, comprising outriggers having feet configured to increase a contact area between the front central lifting system and the ground, the outriggers have a collapsed configuration and an extended configuration, in the collapsed configuration, the feet are located proximate or overlap the foot, in the extended configuration, the feet may be spaced apart from one another and offset from the foot to increase the contact area with the ground.

20. The assembly of claim 12, comprising a beam disposed on top of the first and second rear lifting units and underneath a rear section of the upper part, the first and second rear lifting units spaced apart from one another by a distance greater than a width of the car-body.