JPS5836133B2 - backhoe structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a power shovel, and more particularly to a power shovel that is mounted on a truckter or similar vehicle in such a way that the center of gravity is in close proximity to the truckter to improve balance and handling during loading and transportation. The present invention relates to a conventional loader type backhoe mechanism.

In conventional prior art arrangements, the transport location is a vertical tenon with a folding zipper structure positioned as close as possible to the boom to maintain the main center of gravity for the backhoe as close as possible to the rear of the mounting vehicle. It is characterized by being carried by a boom that extends slightly backwards.

However, the main center of gravity is still located at the rear of the vehicle, and even during normal use as a starter, the mechanical balance is quite unstable and handling is extremely difficult.

In conventional backhoes, proper weight distribution is achieved by placing a counterweight in front of the tracker.

Counterweights have the disadvantage of increasing the overall weight of the vehicle and do not improve stability due to the moment of inertia caused by the length of conventional backhoes.

No. 3,376,984 {Accordingly, these problems are alleviated by arranging the backhoe structure to accommodate over-center movement of the boom cylinder structure when the boom is pivoted into the transport position. There is.

In the transport position, the backhoe is held fixed in position by an over-centered boom cylinder structure with the boom extending vertically and slightly forwardly.

The ability of this boom to assume a very forward canted relational position improves the location of the center of gravity to provide better balance and handling and limit the backhoe tail pivoting required for precision quarter actuation. .

However, the arrangement described in that patent and other prior art arrangements consist of a single unitary boom with boom cylinder structures on both sides, and have the disadvantage that the packets are difficult to see for the operator. There is.

The present invention thus provides a backhoe assembly in which the boom is comprised of a pair of spaced apart hollow boom sections and a single boom cylinder and piston rod assembly is positioned between the boom sections.

This backhoe structure is used when the boom section is pivoted into a transport position where a single over-centered boom cylinder structure holds the boom section fixed in a vertically extending slightly forward position. , to accommodate over-center movement of the boom cylinder.

When the boom section is in the transport position and the boom cylinder is over-centered, the back cover is folded very close to the front of the vehicle, reducing the overall length of the vehicle during transport and controlling the orientation of the vehicle. The distance required to change is reduced compared to conventional backhoe-containing vehicles.

By having a pair of boom sections with a single boom cylinder structure positioned between them, the overall width of said boom sections and single cylinder is reduced by a single boom having a boom cylinder structure on each side. will be smaller than if it were.

Visibility is thus improved as it can be seen through the openings provided between the boom sections.

This is particularly critical when single-serrated tools and very narrow backhoe packets are used.

Another feature of the invention is increased clearance under the backhoe packet during transport.

Unlike conventional backhoes that have a pair of boom cylinder structures on either side of a single boom, the present invention has a pair of boom sections on either side of a single boom cylinder structure so that the boom is substantially vertical. A gap is provided between the boom part and the boom cylinder that allows a neutral position to be occupied.

The boom cylinder assembly controls the boom to pivot to either side of the neutral position.

According to the present invention, only a single boom cylinder assembly needs to be included within the backhoe assembly.

Furthermore, by positioning the boom cylinder assembly between two mutually spaced apart boom sections, said boom section protects the boom cylinder assembly from damage and also protects the hose supplying oil to the packet cylinder. .

Preferably, said hose is positioned within said hollow boom section.

More particularly, the invention includes a vertically extending elongate support fixture having mounting portions for defining upper and lower horizontal pivot axes.

The elongated boom includes two transversely spaced apart boom sections each pivotally mounted at one end on the lower pivot axis.

The two boom sections are rigidly interconnected at their respective upper and lower ends f to prevent relative twisting of the boom sections during operation of the packet.

According to one aspect of the present invention, the two boom sections are hollow rectangular members, and the kneading member, etc.
They are interconnected at their respective ends by rigid sleeves and at their respective upper ends by bracket support devices.

The boom sections are also positioned to move through a neutral intermediate position in which the boom sections extend substantially vertically, and the upper pivot axis is positioned within a space between the boom sections. .

A double-acting boom cylinder assembly is pivotally mounted on the upper pivot axis at one end and extends into the space between the boom sections at the other end.
This is centrally located.

The boom cylinder assembly is extendable and retractable to pivot the boom and boom cylinder mechanism to either side of the neutral intermediate position.

A material handling unit is pivotally mounted on a bracket interconnection system interconnecting opposite ends of the boom sections.

In one variation, the bracket interconnection device includes a bracket having a plurality of protrusions extending into a hollow open end of the boom portion and a material handling unit pivoted to the outer end of the bracket.

In another variation, the bracket interconnection includes an axle extending between the boom sections, and a material handling unit is mounted on the axle between the boom sections.

A fluid ram system is used to pivot the material handling unit.

A bracket arrangement is mounted to the intermediate portion of each boom section, and the fluid ram arrangement is pivotally mounted to the bracket arrangement at one end and to the material handling unit at the other end. .

In one embodiment f, the fluid ram device includes a single cylinder and piston rond assembly.

In another embodiment, the fluid ram device includes a pair of cylinder and piston rond assemblies.

In the accompanying drawings, there is shown a backhoe assembly 10 suitable for being pivotally mounted to the rear of a tracker, as disclosed in the aforementioned U.S. Pat. No. 3,376,984.

Accordingly, the specifications of the above-mentioned US patents are hereby incorporated by reference insofar as they are consistent with the present invention.

The backhoe structure 10 (FIG. 2) includes a support fixture in the form of a swinging tower 12, and the support fixture 12 has upper and lower cylindrical openings 14 and 16, into which a tracker is connected. A swivel pin (not shown in FIG. 2) is inserted into the rearwardly projecting mounting bracket to pivotably mount the swing tower or support fixture.

The swing tower 12 has swing cylinder structures 18 and 2.
Positioned by 0.

The swing tower 12 has a mounting portion having a lower horizontal pivot shaft 22 on which a boom 24 is mounted and an upper horizontal pivot shaft 26 on which a boom cylinder assembly 28 is mounted.

According to the invention, boom 24 is comprised of a pair of spaced hollow rectangular sections 30 and 32.

The hollow rectangular boom sections are pivotably mounted at one end on a lower horizontal shaft 22 through a sleeve 23 extending between and fixed to the boom sections.

The boom cylinder assembly 28 is of the double acting type and includes a cylinder 33 and an axle 3 positioned adjacent to, but spaced from, the free end of said boom section.
6 and a piston rod 34 pivotally connected on boom portions 30 and 32 and positioned within a cavity defined between boom portions 30 and 32.

The free ends of the boom sections 30 and 32 are arranged such that the zipper stick assembly 40 defines a pivot axis for the zipper at a location midway through the length of the zipper but substantially closer to the boom end than the packet end of the zipper. It is mounted on a pivot shaft 42 extending between the sections.

Jitzpa cane assembly 40 includes a rigid mounting plate 44 that receives a pivot shaft 42 and defines a lower end of the Jitzpa cane assembly.

A fluid ram arrangement is used to pivot the zipper stick assembly.

1 and 2, brackets 48 and 5
0 are mounted to the intermediate portions of bum portions 30 and 32, respectively, but may alternatively be integral with said portions.

The bracket is U-shaped in cross section and has voids between its vertical walls.

The brackets have a pivot axis 52 extending therebetween.

In the preferred embodiment illustrated in FIGS. 1 and 2, the fluid ram arrangement comprises a single zipper cylinder assembly 54, also double acting.

The zipper cylinder assembly 54 has a cylinder 55 and a piston rod 56, and the piston rod 56 is pivotally connected to a pivot shaft 58 which is carried in an end corner of the mounting plate 44 and is connected to the pivot shaft. 42.

A zipper cylinder 55 is pivotally mounted on a pivot shaft 52 between brackets 48 and 50.

A packet 70 is conventionally pivotally attached to the free end of the zipper.

A pair of drive links 72, 74 connect zipper 40 and packet 7.
0 and are interconnected by a floating knee shaft 76.

A double-acting packet cylinder structure 78 is attached to the zipper mounting plate 4.
Cylinder 7 on a pivot shaft 80 carried in the upright corner of 4
9 and a single end piston rod 82 is pivotally connected to the knee shaft 76.

The backhoe structure of the present invention has a normal transport position as shown in solid lines in FIG.

That is, in this position, the boom extends vertically and slightly forward, and the center of gravity of the backhoe portion is close to the front end of the tracker.

The boom cylinder assembly 28 has a moment elbow M such that when hydraulic pressure is applied to the head end of the boom cylinder, the boom 24 tends to be forced forwardly toward the swing tower 12, thereby causing the parts to collapse. You can obtain a lock joint that maintains the position shown in Figure 1, if desired.
Bolts (not shown) through which boom 24 passes through boom sections 30 and 32 and holes 88 in swing tower 12
It may be mechanically fixed to the swing tower 12 by.

Since the effective center of gravity has been moved more than 50% forward compared to conventional prior art structures, the balance and maneuverability of the unit is significantly improved.

Swing tower 12 includes a vertical wall 90 having horizontal upper and lower forwardly projecting walls 91 and 92 having openings 14 and 16 for receiving mounting brackets 93 on the tracker.

Swing hoe 12 further includes a pair of rearwardly projecting side walls 94 that define a groove-shaped cavity therebetween into which boom portions 30 and 32 fit.

A sleeve or elongate spacer bearing 23 is secured to the boom sections 30 and 32 and maintains said boom sections in spaced relationship with each other;
Accept 2.

Swing tower 12 also has a vertical wall 96 projecting rearwardly from a centrally located position on the upper portion of swing tower 12.

Vertical wall 96 has an upper horizontal pivot shaft 26 on which boom cylinder 33 is mounted.

A gap is provided between boom sections 30 and 32 and boom cylinder assembly 28.

This arrangement allows the boom to be fully pivoted into a nested position forward of vertical line A--A in FIG.

This position is the transport position and is the boom cylinder structure 28
is positioned partially between boom sections 30 and 32.

In this backhoe operation, normal loading occurs as usual.

However, the boom 24 moved the center of the backhoe to the swing tower 1.
2 can be oriented to a true vertical position and operated closer together to improve balance and handling characteristics.

When the backhoe is pivoted from the phantom line position of FIG. 1 to the solid line position of FIG.
Hydraulic pressure is applied to the rod end of the boom cylinder assembly 28 to pivot it slightly forward of its vertical position, aligned with the centerline of the boom cylinder assembly 28.

The forward momentum of these parts allows the backhoe to continue to advance toward the solid line position in FIG. 1 through this position where the centerlines are aligned.

Hydraulic pressure is applied to the piston end of the boom cylinder assembly 28 to assist in forward movement of the boom between the centerline alignment position and the transport position shown in solid lines in FIG.

Hydraulic pressure then provides a backlash to the boom that holds it in the transport position.

In a neutral position, shown as line B-B in FIG. It will be noted that the swing tower 12 mounts the boom cylinder pivot shaft 26 slightly behind the boom pivot shaft 22 so that it is tilted slightly forward.

This allows hydraulic pressure to actuate the boom cylinder structure in a direction that assists in the last forward increment of travel (forward direction to ensure that the backbone pivots over-center). A very active control is provided to assist in the momentum of the vehicle.

Move the backflight from the solid line position in Figure 1 to the phantom line position in Figure 1 (
To move in this direction, hydraulic pressure is applied to the rod end of the boom cylinder assembly 28 to initiate a rearward pivoting motion of the boom.

Packet cylinders 78 are actuated simultaneously so that packet 70
is hoisted rearward, thereby rapidly moving the center of gravity rearward and assisting in sending the boom rearward.

After movement of the sections through the position shown by line B--B in FIG. released from the rond end.

In the following part of the text, two-digit symbols are used to refer to the embodiments of FIGS. 1 and 2, and three-digit symbols 1
00-199 are used to refer to the embodiment illustrated in FIG.
Used to refer to the embodiments illustrated in the figures.

The same last two digits within each reference number indicate similar elements in various embodiments.

In the embodiment illustrated in FIGS. 3 and 4,
The fluid ram has a pair of jitter cylinder structures 160, 162.
It consists of

In particular, in FIG.
2 are of the double acting type and each has a cylinder 164 pivotally mounted at one end on a pivot shaft 152 and each zipper cylinder is mounted between the parallel side walls of the associated bracket. is positioned.

Each of the zipper cylinder structures 160 and 162 is attached to the mounting plate 14.
4 has a single-ended piston rond 165 pivotally connected to a pivot shaft 158 on the piston.

Backhoe 110 is otherwise identical to backhoe 10 of FIGS. 1 and 2.

In the embodiment illustrated in FIG. 4, brackets 249 and 251 are solid and zipper cylinder 26
4 has mounting members 266 and 267 mounted at one end thereof for separately pivotally mounting the G-coupling cylinder on the bracket.

A piston rod 265 is pivotally connected to pivot shaft 258.

Backhoe 210 is otherwise identical to backhoe 10 illustrated in FIGS. 1 and 2.

Still other modified forms of the invention are illustrated in FIGS. 5, 6 and 7.

Many of the elements illustrated in the embodiments of FIGS. 5, 6, and 7 are the same or very similar to those described in connection with the embodiments of FIGS. 1 and 2. As such, a three-digit code will be used to describe this embodiment.

As in the embodiment shown in FIGS. 1 and 2, the boom 324 is separated from a pair of transversely spaced hollow rectangular boom sections 330 and 332;
The boom sections are interconnected at their respective lower ends by a sleeve 323 pivotally supported on an axle 322.

As shown in FIGS. 5 and 6, sleeve 323 extends through both hollow boom sections 330 and 332 and is rigidly secured thereto, for example by welding.

The hollow boom section 330 and 332 is pivoted about a pivot pin or axis 322.

Shaft 336 extends through a hollow sleeve 337 which is rigidly secured to boom sections 330 and 332, respectively, by welding, for example.

Preferably, the pivot shaft 336 is also welded to the sleeve 337 and/or hollow boom sections 330 and 332O.

Thus, sleeve 337 and shaft 336 are connected to boom portion 33.
A rigid interconnection device is defined between 0 and 332.

According to this arrangement, the sleeve 337 is attached to the piston rod 3.
Acts as a spacer to keep 34 centered between the two boom sections.

Embodiments illustrated in FIGS. 5, 6 and 7 {
Here, the interconnection device between boom sections 330 and 332 also incorporates a bracket support device 341 consisting of a hollow rectangular member 343, and said member 341 secures a bracket 345 to opposite walls thereof. has been done.

The transverse dimension of the hollow member 343 is substantially the same as the spacing between the boom sections 330 and 332, and a bracket 345 preferably has a protrusion 347 projecting from the lower end, allowing it to be welded to the member 343. ing.

A protrusion 347 is received in the open ends of the hollow rectangular boom sections 330 and 332 to provide yet another interconnection between said two boom sections, thus ensuring that said boom sections are not connected to the normal operation of the foot stick assembly. substantially defines a rigid, unitary unit capable of withstanding significant torsional stresses within.

The hollow member 343 also has a sleeve 349 at its outer free end that receives a pivot shaft 342 for pivotally supporting the small stick assembly 340 at the outer end of the boom 324.

Thus, like the embodiments described above, the embodiment of FIGS. 5, 6, and 7 includes three rigid interconnections 323, 336, and 341 between the two boom sections.

The lower ends of boom sections 330 and 332 are preferably provided, for example by a plate 351 welded to said boom section, so that said hollow boom section can be completely enclosed and used as a reservoir for hydraulic fluid if desired. Preferably closed.

However, in the embodiment illustrated in FIGS. 5, 6, and 7, the fluid ram 354 and conduits supplying hydraulic fluid to the packet cylinder assembly (not shown) are connected to the hollow boom section 330 and 332.

As shown most clearly in FIGS. 5 and 7, and particularly in FIG. and terminates in a connector 363 (FIG. 5) at the upper end of bracket support 341.

Thus, a flexible hose 365 can be connected to the connector 363 and to the cylinder assembly (not shown).

It will be appreciated that two such conduits per cylinder assembly may be positioned within either boom section 330 or 332.

Similarly, a conduit (not shown) is connected to the hollow boom section 3.
30 or 332 and a portion of the hollow enclosed bracket 350 to extend the connector 35
1 can terminate in a connector 351 with a hose 353 extending from the fluid ram 354.

Again, two such conduits would be used to supply fluid to opposite ends of ram 354.

All these conduits or hoses may be flexible members or otherwise connectors 351 and 36.
3 may be a rigid member.

Yet another slightly modified version of the invention disclosed in FIG. 8 is similar in all respects to the embodiment of FIGS. an interconnection device at the upper end of the .

FIG. 8 In the illustrated embodiment, each of the hollow rectangular boom sections 430 and 432 extends through the opening 415 to open the respective boom sections 430 and 432.
It has a sleeve 413 welded to.

A shaft 417 extends through each sleeve, which are spaced apart from each other at their inner ends, and the sleeves pivotally support a zipper stick assembly 440.

In this embodiment, the upper interconnection device includes a sleeve 413 and shaft 417 defining a first shaft arrangement and a sleeve 336 and shaft 337 defining a second shaft arrangement.

The Jitsupa stick structure 440 is a rectangular hollow member 42
From 1 onwards, said hollow member has a bearing member 423 extending therethrough and secured, for example, by welding.

The bearing member 423 includes not only the sleeve 413 but also the shaft 4.
17 defines a pivot connection of the zipper stick assembly 440.

In order to make this whole unit rigid, a bearing member 42
Preferably, the area surrounding 3 is reinforced by an additional plate 425.

The bearing member 423 has an opening 427 for supplying lubricant to the relatively moved surfaces.

In the embodiment illustrated in FIG.
13 and a shaft 417, and a sleeve 3.
A second axle system including axle 36 and axle 337 establishes a rigid interconnection between two spaced apart boom sections 430 and 432 at one end of said boom sections. .

The interconnection device also includes a sleeve 323 at the lower end of the boom section.

To summarize the invention, in all embodiments of the invention disclosed herein, boom sections that are transversely spaced apart from each other are constructed such that an operator can create a gap between said boom sections and a single boom cylinder assembly. The packet can be viewed directly from the worker's position through the zipper stick structure, giving the worker a greater field of view than before to observe the operation of the packet at the outer end of the zipper stick structure.

This is especially true when the boom is in the lowered position.

That is, the only obstruction at this location between the boom sections is the piston field of the packet cylinder assembly, which is typically less than half the spacing between the boom sections.

This will significantly increase the visibility an employee has of the material handling unit at the outer end of the overall structure.

Also, the use of two hollow rectangular boom sections and a single boom cylinder assembly significantly reduces the overall cost as well as the overall weight of the backhoe unit.

Not only does this overall weight reduction result from the use of only a single cylinder while still maintaining the over-center features mentioned above, but also the hydraulic pressure required in the reservoir because one of the fluid rams is eliminated. It also reduces the amount of fluid.

Also, as previously explained, the boom cylinder assembly, and in particular its piston rond, is protected at all times by two boom sections on opposite sides to eliminate exposure of the piston rond to damage.

In addition to the above advantages, the structure of the illustrated embodiment, particularly that of FIG. 5, allows the use of currently commercially available zipper stick structures.

Of course, reducing the overall weight of the backhoe unit improves the overall balance of the vehicle during transport.

The use of two boom sections and a single boom cylinder assembly increases the overall width of the boom assembly without sacrificing the overall length of the boom assembly, such as that described in the aforementioned U.S. patent specification. It has been found that it is possible to reduce this by more than 35%.

[Brief explanation of the drawing]

FIG. 1 is a side view of the backhoe of the invention, showing in solid lines the parts in the maximum transport position with the bum cylinder overcentered with respect to the bum to provide a neutralizing action, and in the rearward position occupied during excavation. Figure 2 is a perspective view of the backhoe of Figure 1, in which the backhoe has a structure of a single cylinder and piston rod, and Figure 3 shows a backhoe with a pair of cylinders and piston rods. FIG. 4 is a perspective view similar to FIG. 3, showing another alternative embodiment of the invention, including a piston rond structure; 5 is a side view similar to FIG. 1 showing one particular structure for the boom; FIG. 6 is a side view similar to FIG. 7 is an enlarged sectional view of the upper end of the boom shown in FIG. 6; FIG. 8 is a cross-sectional view similar to FIG. It is a figure showing the changed structure. 10... Backhoe structure, 12... Elongated support fixture, 1B, 20... Double acting boom cylinder structure, 22
...Lower horizontal pivot axis, 23...Sleeve, 2
4... Elongated boom, 26... Upper horizontal pivot axis, 30. 32... Two mutually spaced transversely spaced rectangular hollow boom sections, 40... Jitsupa stick structure, 48. 50... Bracket device, 54... Fluid ram device, 58... Shaft.

Claims (1)

Claims: 1. In a bankhoe structure, a vertically extending elongate support fixture having mounted portions defining upper and lower horizontal pivot axes, each pivoting at one end about the lower pivot axis; An elongated boom comprising two freely mounted, transversely spaced apart, rectangular hollow boom sections, the upper pivot axis being within the cavity between the sections. an elongate boom pivotable on the lower pivot axis through a neutral intermediate position in which the boom portion extends substantially vertically so as to be positioned; and a rigid unit with the boom portion; an interconnection device pivotally mounted on the upper pivot axis and extending within the cavity between the boom sections; a double-acting boom cylinder assembly mounted on the boom so as to be telescoping to pivot the boom and cylinder mechanism on the lower pivot axis to either side of the neutral intermediate position; a double-acting boom cylinder structure,
a material handling unit pivotally mounted to the other end of the boom. 2. The backhoe structure of claim 1, wherein said interconnection device extends between said boom sections and is fixed to each boom section to provide a pivot connection of said boom on said lower pivot axis. A backhoe structure including a sleeve at said one end defining a backhoe structure. 3. The backhoe structure of claim 2, wherein the hollow boom section is open at the other end and the interconnection device includes a bracket having a projection extending into the hollow open end, Backhoe structure, characterized in that the unit is pivotally mounted on the free end of the bracket. 4. A backhoe structure according to claim 2, wherein the interconnection device includes a shaft extending between and fixed to the boom sections, on which the material handling unit is mounted. A backbone structure characterized by being pivoted.