CN114592554A

CN114592554A - Work machine, vertical lifting boom assembly and radial lifting boom assembly

Info

Publication number: CN114592554A
Application number: CN202111292850.XA
Authority: CN
Inventors: N·T·库布哈尔; J·W·李; G·A·吴珊
Original assignee: Deere and Co
Current assignee: Deere and Co
Priority date: 2020-12-03
Filing date: 2021-11-03
Publication date: 2022-06-07
Also published as: DE102021211934A1; US20220178105A1

Abstract

The invention relates to a working machine, a vertical lifting boom assembly and a radial lifting boom assembly. The work machine includes a main frame, a cab, and a boom assembly. The main frame extends in the front-rear direction. The cab may be coupled to the main frame. A boom-assembly is movably coupled to the main frame at a boom-assembly pivot, wherein the boom-assembly is movable between a retracted position and an extended position. The boom-assembly pivot is located rearward of the cab and has a common location for both the vertically-lifting boom-assembly and the radially-lifting boom-assembly. In another embodiment, the boom assembly pivot axis accommodates both vertical lift boom assemblies and radial lift boom assemblies in an interchangeable manner.

Description

Work machine, vertical lifting boom assembly and radial lifting boom assembly

Technical Field

The present disclosure relates to work machines having a boom assembly with one or more of a radial lift path and a vertical lift path as suitable for skid steer loaders and compact track loaders.

Background

Work machines such as skid steer loaders and compact track loaders are used in a variety of environments and in a variety of applications due to their small size, versatility and maneuverability. Depending on the particular application, a work machine may benefit from a boom assembly having a radial lift path or a vertical lift path. The boom of the boom assembly may be coupled to a main frame of the work machine, wherein a portion of the boom coupled to the attachment may be raised and lowered vertically or radially according to a driver's command. In one exemplary case, a work machine having a fork lift type attachment may benefit from a boom assembly having a vertical lift path. Radial lift paths are generally suitable for several other applications, such as moving material with bucket attachments. Manufacturers currently provide work machine configurations having a main frame and a linkage that operates in either a radial lift or a vertical lift rather than both lifts. That is, the boom assembly is constrained to move along a single predetermined path. This may be more costly than necessary in the case of creating two different sub-component designs for each type. There is a need for an improved work machine that accommodates more than one type of boom assembly, where each boom assembly travels along a different path, while maintaining operability and reach. Further, there is an opportunity for improvement to increase productivity.

Disclosure of Invention

This summary is provided to introduce a selection of concepts that are further described below in the detailed description and accompanying drawings. This summary is not intended to identify key or essential features of the appended claims, nor is it intended to be used as an aid in determining the scope of the appended claims.

The present disclosure includes a work machine including a main frame, a cab, and a boom assembly.

The main frame extends in the front-rear direction. The cab may be coupled to the main frame. A boom-assembly is movably coupled to the main frame at a boom-assembly pivot, wherein the boom-assembly is movable between a retracted position and an extended position. The boom-assembly pivot is located rearward of the cab and has a common location for both the vertically-lifted boom-assembly and the radially-lifted boom-assembly. In another embodiment, the boom assembly pivot may interchangeably accommodate vertically lifting the boom assembly and radially lifting the boom assembly.

In a first embodiment of a work machine having a vertically lifted boom-assembly, the main frame includes a pair of supports that support the boom-assembly. The pair of supports are positioned on each side of the main frame and rearward of the cab. The pair of supports may also extend upwardly and terminate at an upper end that is located substantially above the support surface of the main frame and below the line of sight of a driver sitting in the cab. In one embodiment, the boom-assembly pivot may be positioned on an upper portion of the support. The pair of supports may be located forward of the air intake inlet, with the air intake inlet being positioned on each side of the main frame.

The vertical lift boom assembly may include a pair of booms positioned on each side of the main frame. Each boom includes a front portion and a rear portion. The rear portion includes a prong having a first portion and a second portion. The front portion is for coupling to an accessory. A pair of first links are positioned on each side of the main frame. The first link is coupled to the first portion of the prong and the main frame. The pair of second links extend in an upright direction at each side of the main frame. The second link may be coupled to the second portion of the fork and the boom assembly pivot. A pair of actuators is positioned on each side of the main frame, coupled to the main frame and coupled to the boom at or near the forks of the boom, wherein extension of the actuators raises a forward portion of the boom. The front portion follows a vertical lift path as the actuator moves between the retracted position and the extended position. The first link remains below the boom when the actuator moves between the retracted position and the extended position. The coupling of the fork and the second link forms a viewing window.

According to another aspect of the present disclosure, the second embodiment of the boom assembly includes radially lifting the boom assembly. The radial lift boom assembly includes a pair of booms and a pair of actuators extending in a fore-aft direction and positioned on each side of the main frame. Each boom may include a front portion and a rear portion. The rear portion may be coupled to the main frame at a boom-assembly pivot, and the front portion may be used to couple accessories. The forward portion follows a radial lift path as the boom assembly moves between the retracted position and the extended position. A pair of actuators extends in the front-to-rear direction and is positioned on each side of the main frame. An actuator is coupled to the support and the forward portion of the boom, wherein extension of the actuator lifts the forward portion of the boom. The pair of actuators is positioned below the boom when moving between the retracted position and the extended position. The boom assembly pivot may include a double shear joint. The boom assembly does not have a cross bar.

In another aspect of the present disclosure according to the second embodiment, a work machine includes a main frame extending in a fore-aft direction, a cab, and a boom-assembly pivot, where the boom-assembly pivot interchangeably accommodates vertical lifting of a boom assembly and radial lifting of a boom assembly. The vertical lift boom assembly for this embodiment includes a boom extending in the fore-aft direction and positioned on each side of the main frame. A pair of first vertical links is positioned on each side. Each first vertical link is coupled at one end to a rearward portion of the boom and at another end to a boom assembly pivot. A pair of second vertical lift links is positioned on each side. Each second vertical lift link is coupled at one end to a rearward portion of the boom and at another end to an upward portion of the main frame that is below the line of sight of a driver seated in the cab. A pair of actuators is positioned on each side of the main frame. Each actuator is coupled to a boom and a main frame, wherein extension of the actuator lifts a forward portion of the boom. The coupling of the actuator, boom, and second vertical lift link forms a viewing window. In this embodiment, the first vertical lift link, the second vertical lift link, and the actuator are positioned below the boom when moving between the retracted position and the extended position.

In another aspect of the present disclosure, according to a second embodiment, a radial lift boom assembly for this embodiment includes a pair of upwardly extending supports positioned on each side of the main frame and rearward of the cab. Each support is fixedly coupled to the main frame at a boom-assembly pivot, with an upper portion of each support terminating below a line of sight of a driver seated in the cab. A pair of movable arms extend in the front-rear direction and are positioned on each side of the main frame. The rear portion of the boom is pivotably coupled to the upper portion of the support. The front portion is for coupling to an accessory. The forward portion follows a radial lift path as the boom assembly moves between the retracted position and the extended position. A pair of actuators is coupled to the lower portion of the support and the forward portion of the boom, wherein extension of the actuators lifts the forward portion of the boom.

These and other features will become apparent from the following detailed description and the accompanying drawings, wherein various features are shown and described by way of illustration. The disclosure is capable of other and different constructions and its several details are capable of modification in various other respects, all without departing from the scope of the disclosure. The specification and drawings are, accordingly, to be regarded in an illustrative rather than a restrictive or limiting sense.

Drawings

The detailed description of the drawings refers to the accompanying drawings in which:

FIG. 1 is a side view of a first embodiment of a work machine having a vertically lifted boom assembly;

FIG. 2 is a front perspective view of the first embodiment of FIG. 1;

FIG. 3 is a rear perspective view of the first embodiment of FIG. 1;

FIG. 4 is a side view of a first embodiment of a work machine having a radially raised boom assembly;

FIG. 5 is a front perspective view of the first embodiment of FIG. 4;

FIG. 6 is a rear perspective view of the first embodiment of FIG. 4;

FIG. 7 is a side view of a second embodiment of a work machine having a vertically lifted boom assembly;

FIG. 8 is a front perspective view of the second embodiment of FIG. 7;

FIG. 9 is a rear perspective view of the second embodiment of FIG. 7;

FIG. 10 is a side view of a second embodiment of a work machine having a radially raised boom assembly;

FIG. 11 is a front perspective view of the second embodiment of FIG. 10;

FIG. 12 is a rear perspective view of the second embodiment of FIG. 10;

fig. 13 is a graph showing normalized lifting force compared to a current Deere compact track loader.

Like reference numerals are used to refer to like elements throughout the several views.

Detailed Description

The embodiments disclosed in the above drawings and the following detailed description are not intended to be exhaustive or to limit the disclosure to these embodiments. Rather, several variations and modifications may be made without departing from the scope of the present disclosure.

As used herein, unless otherwise limited or modified, a list of elements that have been separated by a linking term (e.g., "and") and preceded by the phrase "one or more" or "at least one" indicates a construction or arrangement that may include the individual elements of the list, or any combination thereof. For example, "at least one of A, B and C" or "one or more of A, B and C" means the possibility of any combination of two or more of A only, B only, C only, or A, B and C (e.g., A and B; B and C; A and C; or A, B and C).

Fig. 1-12 illustrate a work machine 100(100a, 100b, 100c, and 100d), which is illustrated as a compact track loader having an attachment 105 operatively coupled to the work machine 100. However, it should be appreciated that the work machine may be one of many types of work machines, including skid steer loaders and other similar construction or agricultural work machines. The illustrated work machine 100 has a main frame 110 extending in a fore-aft direction 115 with a front end section or portion 120 and a rear end section or portion 125. Work machine 100 includes a ground engaging mechanism 155 that supports main frame 110 and a cab 160 supported on main frame 110, where ground engaging mechanism 155 is configured to support main frame 110 on surface 135.

Work machine 100 may be operated to engage surface 135 and cut, move, lift, and transport material to achieve simple or complex features on the surface, or to harvest resources.

Work machine 100 includes a boom assembly 170 movably coupled to main frame 110. Accessory 105 or a work tool may be pivotally coupled at forward portion 175 of boom-assembly 170, while rearward portion 180 of boom-assembly 170 is pivotally coupled to main frame 110 at boom-assembly pivot 197. The example embodiment boom assembly includes a pair of booms 190 (one on each of the left and right sides) and is movable between a retracted position 193 and an extended position 195 (shown in phantom), including positions between the retracted and extended positions (again shown in phantom). Boom-assembly pivot 197 is located rearward of cab 160 and has a common location for both vertical lift boom-assembly 203 (shown in fig. 1-3, 7-9) and radial lift boom-assembly 205 (fig. 4-6, 10-12). That is, as boom 190 is raised by actuation of actuator 207, an attachment (here shown as a bucket) coupled to forward portion 175 of boom-assembly 170 will move along an almost vertical lift path 210 or a radial lift path 212, allowing both types of work machines to have a common main frame 110. In some embodiments, boom assembly pivot 197 interchangeably accommodates vertical lift boom assembly 203 and radial lift boom assembly 205. In other embodiments, main frame 110 (which includes boom assembly pivot 197) may interchangeably accommodate vertical lift boom-assembly 203 and radial lift boom-assembly 205.

Accessory 105 may be coupled to boom-assembly 170 via an accessory coupler (not identified). An exemplary accessory coupler (commonly referred to as the Quik-Tatch of Deere corporation) is an industry standard configuration, and the coupler is universally applicable to many Deere accessories and several after-market accessories. The attachment coupler is coupled to a forward portion 175 of boom assembly 170.

Fig. 1-3 illustrate a first embodiment of a work machine 100a having a vertically lifted boom assembly 203. This embodiment 100a shares a common boom assembly pivot 197 with fig. 4-6, which illustrate a first embodiment of a work machine 100b having a radially raised boom assembly. Fig. 7-9 illustrate the second embodiment 100c having a vertically lifted boom-assembly 203, the second embodiment 100c sharing a common boom-assembly pivot 197 with fig. 10-12, and fig. 10-12 illustrate the second embodiment 100d having a radially lifted boom-assembly 205.

Turning now to fig. 1-6, main frame 110 of the work machine includes a pair of supports 215 that support boom assembly 170. The pair of supports 215 (on the left and right sides, respectively) are positioned on each side of the main frame 110 and behind the cab 160. The pair of supports 215 extend upward and terminate at an upper end that is located substantially above the support surface 220 of the main frame 110 and below the line of sight of an operator sitting in the cab 160. Boom assembly pivot 197 is positioned on upper portion 222 of support 215. The pair of supports 215 are located in front of the intake inlet 225, which is positioned at each side of the main frame 110, thereby improving the ease of access and reducing maintenance time. In conventional configurations, the intake air inlet may be restrictive and limit accessibility for maintenance and repair, wherein the inlet is limited to only the rear surface 230 of the work machine. Implementing the intake air inlet on the side, in addition to the rear of the work machine (as shown), advantageously improves cooling and serviceability.

As shown in the first embodiment of fig. 1-3, vertically lifting boom-assembly 203 (i.e., lifting path 210 is substantially vertical when boom-assembly 170 is moved between retracted position 193 and extended position 195, where extended position 195 is shown in phantom) includes a pair of booms 190 extending in fore-aft direction 115 on each side of main frame 110. Each boom 190 includes a front portion 175 and a rear portion 180. The rear portion 180 includes prongs 235 having a first portion 240 and a second portion 245. The front portion 175 of the boom 190 is for coupling to the attachment 105. A pair of first links 250 are positioned at each side of the main frame 110. The first link 250 is coupled to the first portion 240 of the fork 235 and the main frame 110, or more specifically to a portion of the main frame 110 that is below the cab 160. A pair of second links 255 extends in the upright direction 117 on each side of the main frame 110. A second link 255 is coupled to the second portion 245 of the fork 235 and the main frame 110, or more specifically to the support 215 at or near the boom assembly pivot 197. A pair of actuators 207 is positioned on each side of main frame 110, coupled to each respective boom 190 at or near a fork 235 of boom 190 and coupled to an area of main frame 110 below cab 160. This configuration results in lifting the forward portion 175 of the boom 190 when the actuator 207 is extended. When moving between the retracted position 193 and the extended position 195, the first link 250 advantageously remains below the boom 190, optimizing visibility for the driver. In addition, the prong 235 of the boom 190, or more specifically the first and

second portions

240, 245 of the prong 235 coupled to the first and second ends 260, 265 of the second link 255, form a viewable window 270. That is, the visual window 270 improves the visual clearance for the operator, who is typically partially or completely blocked by the linkages, hydraulics, joints, and crossbars in conventional work machines. When moving in the reverse direction, no crossbar 275 (shown in phantom in FIG. 3) clears the visual path. Crossbar 275 is a structural coupling of boom 190 in a direction perpendicular or substantially perpendicular to fore-aft direction 115. In conventional configurations, the crossbar 275 provides support in a variety of linkage configurations having a high height. That is, when the linkage configuration is high, the attachment 105 may be lifted higher (typically obstructing the driver's view) when the actuator 207 is extended. Fig. 13 illustrates the improved lift path height and lift capacity of the configuration shown in fig. 1-3, even without the crossbar 275.

Further, the boom assembly pivot includes a double shear joint. Additionally, all of the rear joints are double shear joints, thereby improving the robustness of the work machine by reducing lateral deflection. Conventional designs use cantilevered joints, which require relatively large pins and heavy structures to achieve similar lateral deflection.

Turning now to fig. 4-6, a first embodiment of a work machine 100b including a radially raised boom assembly 205 is illustrated. Radial lift boom assembly 205 includes a pair of booms 190 extending in fore-aft direction 115, positioned on each side of main frame 110. Each boom 190 includes a front portion 175 and a rear portion 180. Rear portion 180 is coupled to main frame 110 at a boom-assembly pivot 197. As boom-assembly 170 moves between retracted position 193 and extended position 195 (shown in phantom), forward portion 175 for coupling to attachment 105 follows radial lift path 212. A pair of actuators 207 extends in the front-to-rear direction 115 (or substantially in the front-to-rear direction) and is positioned on each side of the main frame 110. The actuator 207 is coupled to the support 215 and the forward portion 175 of the boom 190, wherein extension of the actuator 207 lifts the forward portion 175 of the boom 190. In the illustrated embodiment, the pair of actuators 207 are positioned below the boom 190 when moving between the retracted position 193 and the extended position 195. Similar to the work machine embodiment 100a of fig. 1-3, the work machine embodiment 100b also does not require a crossbar 275.

Fig. 7 to 9 and 10 to 12 show a second embodiment (100c, 100d) of the work machine. Work machine 100c includes a main frame 110 extending in a fore-aft direction 115, a cab 160 coupled to main frame 110, a boom assembly 170, and a boom assembly pivot 197. Boom-assembly 170, which is pivotally coupled to main frame 110, is movable between a retracted position 193 (shown in solid lines) and an extended position 195 (shown in phantom lines). Boom-assembly pivot 197 in the second embodiment is located rearward of cab 160, where boom-assembly pivot 197 has a common location for both vertically lifting boom-assembly 203 and radially lifting boom-assembly 205, thereby allowing a common main frame 110 to be used for both types of work machines. In some embodiments, boom assembly pivot may interchangeably accommodate vertical lift boom assembly 203 and radial lift boom assembly 205. In other embodiments, main frame 110 may interchangeably accommodate vertical lift boom assembly 203 and radial lift boom assembly 205.

Fig. 7-9 illustrate a work machine 100c having a vertically lifted boom assembly 203. Vertical lift boom assembly 203 includes: a pair of movable arms 190 extending in the front-rear direction 115, positioned at each side of the main frame 110; a pair of first vertical lift links 750 positioned on each side; a pair of second vertical lift links 755 positioned on each side; and a pair of actuators 207 positioned on each side. Each first vertical lift link 750 is coupled at one end to the rear portion 180 of the boom 190 and at the other end to a boom assembly pivot 197. Each second vertical lift link 755 (shown in phantom) is coupled at one end to the rear portion 180 of the boom 190 and at the other end to the main frame 110 while remaining at an upward portion below the line of sight 185 of a driver seated in the cab 160. Extension of the actuator 207 lifts the front portion 175 of the boom 190.

The coupling of the actuator 207, the boom 190, and the second vertical lift link 755 forms a visualization window 270.

In this second embodiment, the first vertical lift link 750, the second vertical lift link 755, and the actuator 207 are positioned below the boom 190 when moving between the retracted position 193 and the extended position 195. Boom-assembly pivot 197 may include a double shear joint 232. Additionally, all of the rear joints are double shear joints, thereby improving the robustness of the work machine by reducing lateral deflection. Conventional designs use cantilevered joints, which require relatively large pins and heavy structures to achieve similar lateral deflection.

Fig. 10-12 illustrate a second embodiment of a work machine 100d having a radially raised boom assembly 205, wherein boom assembly pivot 197 has a common location with boom assembly pivot 197 of the second embodiment having a vertically raised boom assembly 203. Radial lift boom assembly 205 includes a pair of upwardly extending supports 215 positioned on each side of main frame 110 and rearward of cab 160. Each support 215 is fixedly coupled to main frame 110 at a boom-assembly pivot 197. Note that support 215 may be considered part of main frame 110 or boom assembly 170. The upper portion 222 of each support terminates below the line of sight 185 of an operator seated in the cab 160.

In this embodiment, the pair of booms 190 extend in the fore-aft direction 115 and are positioned on each side of the main frame 110, wherein each boom 190 includes a front portion 175 and a rear portion 180. The rear portion 180 is pivotably coupled to the upper portion 222 of the support 215. The front portion 175 of the boom 190 is for coupling to the attachment 105. Front portion 175 follows radial lift path 212 as boom-assembly 170 moves between retracted position 193 and extended position 195. A pair of actuators 207 extends in the front-to-rear direction 115 and is positioned on each side of the main frame 110. Each actuator 207 is coupled to a lower portion of the support and a forward portion 175 of the boom, wherein extension of the actuator 207 lifts the forward portion 175 of the boom 190. When moving between the retracted and extended positions, the pair of actuators 207 and support 215 remain below the boom 190, advantageously improving visibility for the driver.

The pair of actuators 207 and the upwardly extending support 215 are positioned forward of the intake inlet when moving between the retracted position 193 and the extended position 195 (shown by dashed lines). Implementing the intake air inlet on the side, in addition to the rear of the work machine (as shown), advantageously improves cooling and serviceability.

Boom-assembly 170 does not have crossbar 275. Crossbar 275 generally couples the arms in a direction perpendicular to the fore-aft direction to provide support.

Turning now to fig. 13, a graph of normalized lift force compared to the current configuration or more specifically to the current Deere compact track loader is shown. Compared to the current Deere track loader, the standardized lifting force curve details are generated by the first embodiment. The first embodiment allows maintaining the initial digging force up to 75% of the lifting height and continuing to maintain a digging force greater than 75% up to more than 90% of the lifting height, thereby advantageously improving productivity in high lift applications.

The terminology used herein is for the purpose of describing particular embodiments or implementations and is not intended to be limiting of the disclosure. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that any use of the terms "has," "contains," "includes," "including," and the like, in this specification, identifies the presence of stated features, integers, steps, operations, elements, and/or components, but does not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

In describing various implementations of the device, the references "a" and "B" used herein with reference numerals are for clarity only.

One or more of the steps or operations in any method, process, or system discussed herein may be omitted, repeated, or reordered and are within the scope of the present disclosure.

While the above describes example embodiments of the present disclosure, these descriptions should not be viewed in a limiting or restrictive sense. Rather, several variations and modifications are possible without departing from the scope of the appended claims.

Claims

1. A work machine, the work machine comprising:

a main frame extending in a front-rear direction;

a cab coupled to the main frame; and

a boom-assembly movably coupled to the main frame at a boom-assembly pivot, the boom-assembly movable between a retracted position and an extended position;

wherein the boom assembly pivot is located rearward of the cab, the boom assembly pivot interchangeably accommodating vertically and radially lifting boom assemblies.

2. The work machine of claim 1, wherein the vertical lift boom assembly comprises:

a pair of booms extending in the fore-and-aft direction and positioned on each side of the main frame, each boom including a front portion and a rear portion;

a pair of first vertical lift links positioned on each side of the main frame, each first vertical link coupled at one end to the rear portion of the boom and at another end to the boom assembly pivot;

a pair of second vertical lift links positioned on each side of the main frame, each second vertical lift link coupled at one end to the rear portion of the boom and at another end to an upward portion of the main frame below a line of sight of a driver seated in the cab; and

a pair of actuators positioned on each side of the main frame and coupled to the boom and the main frame, wherein extension of the actuators lifts the front portion of the boom.

3. The work machine of claim 2, wherein the coupling of the actuator, the boom, and the second vertical lift link forms a visible window.

4. The work machine of claim 2, wherein the first vertical lift link, the second vertical lift link, and the actuator are positioned below the boom when moving between the retracted position and the extended position.

5. The work machine of claim 1, wherein the boom-assembly pivot comprises a double shear joint.

6. The work machine of claim 1, wherein the radially lifting boom assembly comprises:

a pair of upwardly extending supports positioned on each side of the main frame and rearward of the cab, each upwardly extending support fixedly coupled to the main frame at the boom-assembly pivot, wherein an upper portion of each support terminates below a line of sight of a driver seated in the cab;

a pair of booms extending in the fore-aft direction and positioned on each side of the main frame, each boom including a front portion and a rear portion, the rear portion being pivotably coupled to the upper portion of the support and the front portion being for coupling to an attachment, the front portion following a radial lift path as the boom assembly moves between the retracted position and the extended position; and

a pair of actuators extending in the fore-aft direction and positioned on each side of the main frame, each actuator coupled to a lower portion of the support and the front portion of the boom, wherein extension of the actuators lifts the front portion of the boom.

7. The work machine of claim 6, wherein the pair of actuators and the upwardly extending support are positioned below the boom when moving between the retracted position and the extended position.

8. The work machine of claim 6, wherein the pair of actuators and the upwardly extending support are positioned forward of an air intake inlet when moving between the retracted position and the extended position.

9. The work machine of claim 6, wherein the boom assembly is free of a cross bar that couples the boom in a direction perpendicular to the fore-aft direction.

10. A vertical lift boom assembly for a work machine, the work machine having a main frame and a cab, the vertical lift boom assembly comprising:

a pair of booms extending in a fore-and-aft direction and positioned on each side of the main frame, each boom including a front portion for coupling to an accessory and a rear portion;

a pair of first vertical lift links positioned on each side of the main frame, each first vertical link coupled at one end to the rear portion of the boom and at another end to a boom-assembly pivot, wherein the boom-assembly pivot is located rearward of the cab;

11. The vertical lift boom assembly of claim 10, wherein the coupling of the actuator, the boom, and the second vertical lift link forms a visible window.

12. The vertical lift boom assembly of claim 10, wherein the first vertical lift link, the second vertical lift link, and the actuator are positioned below the boom as the vertical lift boom assembly moves between a retracted position and an extended position.

13. The vertical lift boom assembly of claim 10, wherein the boom assembly pivot comprises a double shear joint.

14. The vertical lift boom assembly of claim 10, wherein the boom-assembly pivot has a common location as in the case of a radial lift boom assembly.

15. A radially lifting boom assembly for a work machine, the work machine having a main frame and a cab, the radially lifting boom assembly comprising:

a pair of upwardly extending supports positioned on each side of the main frame and rearward of the cab, each upwardly extending support fixedly coupled to the main frame at a boom-assembly pivot, wherein an upper portion of each support terminates below a line of sight of a driver seated in the cab;

a pair of booms extending in a fore-aft direction and positioned on each side of the main frame, each boom including a front portion and a rear portion, the rear portion being pivotably coupled to the upper portion of the upwardly extending support and the front portion for coupling to an accessory, the front portion following a radial lift path as the boom assembly moves between a retracted position and an extended position; and