AU2004229068A1 - An Apparatus for Cutting or Digging Through a Substrate, and a Hitch Assembly - Google Patents

Description

Al Hydraulic Cylinder Services Pty Ltd

AUSTRALIA

Patents Act 1990 COMPLETE STANDARD PATENT £3 Invention Title: An Apparatus for Cutting and Digging Through a Substrate, and a Hitch Assembly The following statement is a full description of this invention, including the best method of performing it known to us: o 2 K ~BACKGROUND OF THE INVENTION o This invention broadly relates to heavy duty machinery and Z implements therefore. A first aspect of the invention relates to an apparatus having a circular saw blade for cutting or digging through a substrate. A 5 second aspect of the invention relates to a quick hitch assembly that may be 00 0used in respect of the first aspect of the invention, but may also find general application when attaching other types of implements to heavy duty i machinery.

oThe apparatus of the first aspect of the invention has been developed primarily for cufftting substrates such as rock (sandstone in particular) and for digging trenches in the ground and will therefore be described in this context. It is to be appreciated, however, that the apparatus may have other uses.

Excavators, loaders, backhoes and like heavy duty machinery/vehicles are commonly used for digging through earth substrates.

Although these machines are useful for digging through earth, a general disadvantage with such machines is that they may not be adaptable for digging through substrates comprising solid rock, eg. sandstone. Another general disadvantage with some machines is that attaching different implements may be difficult, time consuming and may require more than one person.

An excavator for cutting through sandstone is known. The excavator has a boom and an arm, and the arm is attached to a circular saw blade. A disadvantage with the excavator is that the saw blade poses a danger to the operator of the excavator as the saw blade is unshielded and is positioned immediately in front of the operator cabin of the excavator.

Another disadvantage is that high stresses are placed on the arm and boom when cutting sandstone, and these parts tend to need to be replaced frequently, after about 300 hours of operation.

OBJECT OF THE INVENTION It is an object of the present invention to minimise at least one of the disadvantages referred to above, or to provide the public with a useful or commercial choice.

o 3 cSUMMARY OF THE INVENTION 0 O According to a first aspect of the invention, there is provided an apparatus for cufftting or digging through a substrate, said apparatus having: a fork assembly having an attachment end for attaching to a heavy duty vehicle, and forks extending from the attachment end; 00 oO 00 a circular saw blade supported between the forks and rotatable relative thereto, said saw blade having a front end and a rear end and the rear end is situated adjacent the attachment end, said saw blade having a o plurality of cutters for cutting or digging through a substrate; 0 10 a guard assembly having a cover that houses an upper region of said saw blade and a moveable tongue that may be extended or retracted relative to the cover to either expose or to house the cutters at the front end of the saw blade; a drive for rotating said saw blade; and a sensor system that extends the tongue over the cutters at the front end of the saw blade when the saw blade is not cutting or digging and retracts the tongue when the saw blade is cutting or digging.

Preferably, the saw blade is adapted to be dragged by the heavy duty vehicle whilst cutting or digging through the substrate, and the saw blade rotates counter to the direction of movement of the heavy duty vehicle.

r The fork assembly may be attachable to the heavy duty vehicle in any suitable way. Preferably, the attachment end has an arm, a boom that is pivotally connected to the arm and to the heavy duty vehicle, one or more hydraulic arm cylinders for pivoting the arm relative to the boom, and one or more hydraulic boom cylinders for pivoting the boom relative to the vehicle.

In this way, the saw blade may be raised, lowered or tilted relative to the substrate and vehicle. More preferably, the saw blade may only be pivoted in the plane of the arm and the boom.

Alternatively, the attachment end may be pivotally attachable to a hydraulic arm or boom of the heavy duty vehicle.

Preferably, hydraulic power is provided to the apparatus by the heavy duty vehicle by way of fluid lines or hoses.

Preferably, the apparatus has an axle that suspends the saw blade o 4 0 between the forks, and the forks extend parallel to one another.

O The drive may comprise any suitable motor known to persons skilled in the art. Preferably, the drive comprises a hydraulic motor and a degree gearbox which are connected to a fork of the fork assembly and to an end of the axle.

00 IPreferably, the cutters are adapted to cut through rock or to dig 0 through earth.

cThe cutters and saw blade may be of unitary construction, or each ocutter may be a separate tool or tooth that is mountable to the saw blade by way of a holder, adaptor or mounting. In the latter case, the cutters may be I replaced when worn. Tools, teeth, holders, adaptors and mountings for excavators and like machines are well known in the art.

The cutters may be of any suitable shape and size, and may comprise any suitable material. The cutters may be arranged in any suitable pattern along a circumference of the saw blade. Preferably, the saw blade has 60 cutters, the cutters are arranged in groups of three, the three cutters extend parallel to one another, adjacent groups of three cutters are mirror images of one another, and each group of three cutters extends towards the front end of the saw blade but not co-planarly with the saw blade.

The saw blade may be of any suitable thickness and diameter.

Preferably, the saw blade has a thickness of about 25mm and is about 5000mm in diameter for cutting or digging to a depth of about 2200mm. The saw blade may have cut-out regions for reducing the weight of the blade.

The cover may extend from.the forks and over the saw blade and house about a 135 degree sector of the saw blade. Preferably, the cover houses the upper region of the saw blade between the axle and the attachment end. The cover can have portals or cut outs that may be screened with mesh.

The tongue of the guard assembly is preferably U-shaped when viewed in transverse cross-section. The cover may have an internal track within which the tongue may slide.

The sensor system may comprise any suitable system known to persons skilled in the art. The sensor system may have electronic sensors o 0 that detect pressure changes in hydraulic lines that extend between the drive o and the vehicle. That is, when the saw blade engages the substrate, there may be a change in fluid pressure within the hydraulic lines, the electronic sensors may detect the changes in fluid pressure and extend or retract the tongue accordingly.

O0 0 The sensor system preferably includes a hydraulic guard cylinder

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for extending and retracting the tongue. The guard cylinder may be cconnected to an end of the tongue and to the cover and may be coupled to othe electronic sensors.

The sensor system preferably also has additional sensors connected to other hydraulic components of the apparatus, namely, the drive, the boom cylinders and the arm cylinders.

The sensor system preferably also includes a computer system for coordinating the sensors and hydraulics. The computer system may be programmable and may fully automate the digging and cufftting of the substrate, as well as the movement of the heavy duty vehicle.

The heavy duty vehicle may be an excavator, a tractor or any suitable vehicle that can drag the apparatus along the substrate.

The apparatus may have an extraction system for removing dust and debris produced when cutting or digging through the substrate. The extraction system may, for example, comprise one or more ducts or chutes that extend from adjacent the saw blade and/or cover. The dust and debris may be drawn through the duct or chute under vacuum, say, for instance, by a fan. The dust and debris may be collected and contained, or expelled at a remote site.

According to a second aspect of the invention, there is provided a quick hitch assembly for attaching an implement to heavy duty machinery, said assembly comprising a hydraulic arm having: at least two substantially parallel extending load transmission plates that are attachable to a hydraulic boom of heavy duty machinery and pivotable relative thereto, said load transmission plates each having an upper end and a lower end; a spacer plate from which said load transmission plates extend; o 6 0 N and O a locking mechanism comprising a hydraulic locking cylinder and a Z locking member, wherein said locking cylinder can move the locking member relative to said spacer plate between a locked position and an unlocked position; 0said assembly further comprising a hitching arrangement attachable to or integral with said implement, said hitching arrangement having a surface bordered by an upper rail and a lower rail, said upper rail 1 extending outwardly from the surface towards said lower rail, said lower rail extending outwardly from said surface and being adapted to retain said locking member, wherein said spacer plate and said upper and lower ends of the load transmission plates are dimensioned to partly nest within said hitching arrangement, and when nested and said locking member is moved to the locked position and retained by said rower rail, then said implement is hitched to the heavy duty machinery.

The hitching arrangement may be provided by a hitch plate having the upper rail and the lower rail, and the hitch plate may be attached to or attachable to the implement.

Preferably, the hydraulic arm has two load transmission plates and the locking mechanism is located between these plates.

Preferably, a brace extends between the upper end of each load -transmission plate and this brace is sized to nest between the upper rail and the surface.

The locking member may have a guide plate having an upper end attached to the locking cylinder and a lower end from which extends two locking pins that are receivable within apertures in the lower rail. Preferably, the guide plate has elongate slots, retaining guide members extend from the spacer plate through the slots and prevent the guide plate from moving other than parallel with the spacer plate. Preferably, the guide plate is trapezoidal in shape and has three guide slots.

The apparatus may have a safety feature for preventing the locking cylinder from moving the locking member from the locked position. For instance, a clevis and pin arrangement may be used to lock the locking o7 0 cylinder in place.

O Each load transmission plate may have a first aperture and boss arrangement for receiving a pin for pivotally connecting each load transmission plate to the hydraulic boom. Each load transmission plate may have a second aperture and boss arrangement for receiving a pin for pivotally 00 0connecting the load transmission plates to one or more hydraulic arm

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cylinders. Preferably, each first aperture and boss arrangement is situated above each second aperture and boss arrangement.

oThe hitch assembly may be used to attach the apparatus described 0 10 in the first aspect of the invention to a heavy duty vehicle.

-Preferably, the apparatus and hitch assembly are made chiefly of heavy duty steel.

A preferred embodiment of each aspect of the invention will now be described by way of example with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS -Figure 1 is a partly detailed side elevation view of an apparatus for cutting or digging through a substrate, and having a quick hitch assembly, according to an embodiment of the invention; Figure 2 is a partly detailed top plan view of the apparatus and quick hitch assembly of Figure 1, and additional views for some parts of the apparatus are shown; Figure 3 is a partly detailed top plan view of part of the apparatus and quick hitch assembly of Figure 1; Figure 4 is a partly detailed side elevation view of the apparatus and hitch assembly shown in Figure 3; Figure 5 is a side elevation view of part of the apparatus shown in Figure 1; Figure 6 is a partly detailed and exploded side elevation view of part of the apparatus shown in Figure 1, and an additional view for part of the apparatus is shown; Figure 7 is a side elevation view of part of the apparatus shown in Figure 1; o 8 Figure 8 is a partly detailed top plan view of the part of the 0 O apparatus shown in Figure 7; Figure 9 is a partly detailed end elevation view of part of the quick hitch assembly shown in Figure 1; 5 Figure 10 is a partly detailed side elevation view of part of the quick 00 0hitch assembly shown in Figure 9; and NO 0 Figure 11 is an exploded and partly detailed side elevation view of cthe quick hitch assembly shown in Figure 1.

1DESCRIPTION OF THE PREFERRED EMBODIMENTS In all of the drawings, like reference numerals refer to like parts.

Referring first to Figure 1, there is shown an apparatus 1 for cutting through rock or for digging through earth, according to an embodiment of the first aspect of the invention. The apparatus 1 also has a quick hitch assembly 21, according to an embodiment of the second aspect of the invention.

The apparatus 1 has a fork assembly 2 that has an attachment end 8 for attaching the apparatus 1 to an excavator, a circular saw blade 3 that has a plurality of cutters 4, a guard assembly 5 that has a cover 10 and a moveable tongue 11, a drive 6 for rotating the saw blade 3, and a sensor system that controls movement of the tongue 11. The attachment end 8 has the quick hitch assembly 21.

The excavator provides hydraulic and electrical power to the apparatus 1. Hydraulic lines and electrical wiring are not shown in the figures.

Referring now to Figures 1-4, the fork assembly 2 has two forks 9 that extend parallel to one another and which extend from the attachment end 8. Each end of a fork 9 has a boss 31 and a bearing casing 32 (see Figure A wear plate 33 is attached to an underside of each fork 9 (see Figure 4).

The attachment end 8 has a hitch plate 34 that is secured to the forks 9 with gussets Referring now to Figures 1, 2 and 5, the saw blade 3 is suspended between the forks 9 by an axle 19 and is rotatable relative to the forks 9 by the drive 6 (see Figure The saw blade 3 has a front end and a rear end, and the rear end is situated adjacent the attachment end 8. The saw blade 3 has a thickness of 25mm and is 5000mm in diameter. The saw blade 3 has 9

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N five cut-out regions 12 for reducing the weight of the blade 3 (see Figure O Sixty cutters 4 are arranged in a pattern along the circumference of Z the saw blade 3. The cutters 4 are arranged in groups of three and the three Icutters 4 extend parallel to one another. Adjacent groups of three cutters 4 are mirror images of one another, and each group of three cutters 4 extends 00 generally in the direction in which the saw blade 3 rotates but other than co- 0planarly with the saw blade 3.

CEach cutter 4 comprises a tooth that is mountable to the saw blade -3 by way of an adaptor sleeve that extends from the saw blade 3 (not shown).

Each adaptor sleeve may receive a locking pin for locking the tooth to the sleeve. The cutters 4 are adapted to cut through earth and/or rock.

The drive 6 comprises a hydraulic motor 28 and a gearbox 29 connected to a fork 9 and to an end of the axle 19 (see Figures 1 and 2).

Referring now to Figures 1, 2 and 6, the guard assembly 5 has a cover 10 that extends from the forks 9 and houses an upper region of the saw blade 3. The cover 10 houses about a 135 degree segment of the saw blade 3 at any one time. Each side of the cover 10 has a skirt 17 that extends the length of a lower edge of the cover 10 (see Figure Fasteners 18 attach each skirt 17 to a respective fork 9.

The cover 10 has cut-out regions 13 that may be screened with mesh and serve as portals 13. Any debris that is caught between the saw blade 3 and cover 10 may be seen through the portals 13. The portals 13 also enable dust and other particulate matter to pass therethrough and to be extracted from the cutting or digging site under vacuum via chutes or ducts (not shown).

The tongue 11 of the guard assembly 5 may be extended or retracted relative to the cover 10 to either expose or to house the cutters 4 at the front end of the saw blade 3.

The tongue 11 is U-shaped when viewed in transverse crosssection (see Figure The cover 10 has an internal track 14 within which the tongue 11 may slide. The cover 10 has an elongate slot 15, an end of the tongue 11 has a pin 16 extending therefrom, and the pin 16 extends through *1 N and is slideable within the slot 15 (see Figure 6).

O Referring now to Figure 1, the attachment end 8 has hitch plate 34, Z an arm 23 that can be locked to the hitch plate 34, a boom 22 that is pivotally connected to the arm 23 and to the excavator, dual hydraulic boom cylinders 24 for pivoting the boom 22 relative to the excavator, and dual hydraulic arm 00 cylinders 25 for pivoting the arm 23 relative to the boom 22. The saw blade 3 0 may be tilted, raised and lowered relative to the substrate to be worked.

C The sensor system has electronic sensors (not shown) and a S' hydraulic guard cylinder 30 for moving the tongue 11. An end of the guard cylinder 30 is connected to pin 16 and the other end of the guard cylinder Sis connected to the cover 10. The electronic sensors are attached to each fork 9. The electronic sensors detect pressure changes in hydraulic lines that extend between the drive 6 and the excavator. That is, when the saw blade 3 engages the substrate, there will be a change in fluid pressure within the hydraulic lines, the electronic sensors will detect the changes in pressure and extend or retract the tongue 11 accordingly by way of the guard cylinder The sensor system may have additional sensors connected to other hydraulic components, namely, the drive 6, the boom cylinders 24 and the arm cylinders The sensor system may include a computer system. The computer system may be programmable and may fully automate the digging or cutting of the substrate. The computer may be operable from the excavator cabin.

The excavator may be fitted with safety features. For instance, the cabin may need to be locked to a turntable of the excavator before the saw blade 3 can be activated.

The apparatus 1 may be used to cut sandstone in a blue metal quarry, or to dig trenches for when laying telephone cables. In use, an operator, or a programmed computer, positions the saw blade 3 over the substrate to be worked and operates the saw blade 3. The operator or computer manoeuvres the saw blade 3 by pivoting the boom 22. and/or the arm 23 by way of cylinders 24 and 25. The cut or dug trench may be lengthened by driving the excavator in a direction opposite to the rotational direction of the saw blade 3. This may be done manually or under computer O 11 C control. As the saw blade 3 cuts or digs into the substrate, the sensors cause o the guard cylinder 30 to retract the tongue 11 into the cover 10. The cutting Z or digging is monitored manually by the operator or using the sensor system.

In this way, a 2200mm deep cut or trench may be made in the substrate.

Referring now to Figures 1-4 and 7-11, the boom 22 has a first 00 aperture and boss arrangement 38 for receiving a pin that pivotally connects 0the boom 22 to the excavator. The boom 22 has a second aperture and boss arrangement 39 for receiving a pin that pivotally connects the boom 22 to the boom cylinders 24. The boom 22 has a third aperture and boss arrangement 40 for receiving a pin that pivotally connects the boom 22 to the arm 23. The -boom 22 has a fourth aperture and boss arrangement 41 for receiving a pin that pivotally connects the boom 22 to the arm cylinders The quick hitch assembly 21 comprises arm 23 and hitch plate 34.

Arm 23 has two substantially parallel extending load transmission plates 42, each having an upper end 43 and a lower end 44. Each load transmission plate 42 has a first aperture and boss arrangement 45 for receiving a pin that pivotally connects the arm 23 to the arm cylinders 25. Each load transmission plate 42 has a second aperture and boss arrangement 46 for receiving a pin that pivotally connects the arm 23 to the boom 22.

Each load transmission plate 42 extends from a spacer plate 47. A brace 50 extends between the upper end 43 of each load transmission plate 42.

The arm 23 further has a locking mechanism comprising a hydraulic locking cylinder 48 and a locking member 49. The locking cylinder 48 may move the locking member 49 relative to the spacer plate 47 between a locked position and an unlocked position. The locking member 49 has a trapezoidal guide plate 51 that has an upper end attached to the locking cylinder 48 and a lower end from which extends two locking pins 52.

The guide plate 51 has three elongate slots 53, retaining guide members 54 extend from the spacer plate 47 through the slots 53 and prevent the guide plate 51 from moving other than parallel with the spacer plate 47. Each of the retaining guide members 54 is a bolt 54 having a head spaced from the guide plate 51 by a washer 55 (see Figure 12 N The hitch plate 34 has a flat surface 57 bordered by an upper rail o 58 and a lower rail 59 (see Figure The upper rail 58 extends outwardly Z from the surface 57 towards the lower rail 59. The lower rail 59 extends outwardly from the surface 57 and has apertures 60 for receiving the locking pins 52 of the locking member 49. The spacer plate 47 and the upper 43 and 00 lower 44 ends of the load transmission plates 42 are dimensioned to nest 0partly within the hitch plate 34, as seen in Figures 9 and 11.

(In order to attach the hitch plate 34 to the arm 23, the arm 23 is made to partly nest within the hitch plate 34 and the locking pins 52 are moved to the locked position within the apertures 60 of the lower rail 59. The locking cylinder 48 is activated manually or under computer control. For safety, a clevis and pin arrangement 56 are used to lock the locking cylinder 48 such that the locking member 49 cannot be moved from the locked position.

The arm 23 may be readily attachable to other implements having a hitch plate 34 or essential features of the hitch plate 34.

Whilst the above has been given by way of illustrative example of the invention, many modifications and variations may be made thereto by persons skilled in the art without departing from the broad scope and ambit of the invention as herein set forth.

Claims (21)

1. An apparatus for cutting or digging through a substrate, said apparatus having: 00a fork assembly having an attachment end for attaching to a heavy duty vehicle, and forks extending from the attachment end; a circular saw blade supported between the forks and rotatable 0 relative thereto, said saw blade having a front end and a rear end and the rear end is situated adjacent the attachment end, said saw blade having a plurality of cutters for cutting or digging through a substrate; a guard assembly having a cover that houses an upper region of said saw blade and a moveable tongue that may be extended or retracted relative to the cover to either expose or to house the cutters at the front end of the saw blade; a drive for rotating said saw blade; and a sensor system that extends the tongue over the cutters at the front end of the saw blade when the saw blade is not cufftting or digging and retracts the tongue when the saw blade is cutting or digging.

2. The apparatus of claim 1, wherein the saw blade is adapted to be dragged by the heavy duty vehicle whilst cutting or digging through the substrate, and the saw blade rotates counter to the direction of movement of the heavy duty vehicle.

3. The apparatus of claim 1 or claim 2, wherein the attachment end has an arm, a boom that is pivotally connected to the arm and to the heavy duty vehicle, at least one hydraulic arm cylinder for pivoting the arm relative to the boom, and at least one hydraulic boom cylinder for pivoting the boom relative to the vehicle.

4. The apparatus of any one of the preceding claims further including an axle that suspends the saw blade between the forks, and the forks extend parallel o 14 0 Sto one another. 0 Z

5. The apparatus of claim 4, wherein the drive comprises a hydraulic motor and a 90-degree gearbox which are connected to a fork of the fork assembly and to an end of the axle. 00 ID

6. The apparatus of any one of the preceding claims, wherein the cutters are adapted to cut through rock or to dig through earth. 0

7. The apparatus of any one of the preceding claims, wherein the cutters are arranged in groups of three, the three cutters extend parallel to one another, adjacent groups of three cutters are mirror images of one another, and each group of three cutters extends towards the front end of the saw blade but not co-planarly with the saw blade.

8. The apparatus of claim 4, wherein the cover extends from the forks and over the saw blade and houses about a 135 degree sector of the saw blade, and the cover houses the upper region of the saw blade between the axle and the attachment end.

9. The apparatus of any one of the preceding claims, wherein the tongue of the guard assembly is U-shaped when viewed in transverse cross-section.

The apparatus of claim 9, wherein the cover has an internal track within which the tongue slides.

11. The apparatus of any one of the preceding claims wherein the sensor system includes electronic sensors that detect pressure changes in hydraulic lines that extend between the drive and the vehicle.

12. The apparatus of claim 11, wherein the sensor system includes a hydraulic guard cylinder for extending and retracting the tongue, wherein the guard cylinder is connected to an end of the tongue, to the cover and to the o 0 electronic sensors. 0 Z

13. The apparatus of claim 12, wherein the sensor system includes a computer system for coordinating the electronic sensors and hydraulic components of the apparatus. 00 Va

14. The apparatus of any one of the preceding claims further having an extraction system for removing dust and debris produced when cutting or 0 digging through the substrate. A quick hitch assembly for attaching an implement to heavy duty machinery, said assembly comprising a hydraulic arm having: at least two substantially parallel extending load transmission plates that are attachable to a hydraulic boom of heavy duty machinery and pivotable relative thereto, said load transmission plates each having an upper end and a lower end; a spacer plate from which said load transmission plates extend; and a locking mechanism comprising a hydraulic locking cylinder and a locking member, wherein said locking cylinder can move the locking member relative to said spacer plate between a locked position and an unlocked position; said assembly further comprising a hitching arrangement attachable to or integral with said implement, said hitching arrangement having a surface bordered by an upper rail and a lower rail, said upper rail extending outwardly from the surface towards said lower rail, said lower rail extending outwardly from said surface and being adapted to retain said locking member, wherein said spacer plate and said upper and lower ends of the load transmission plates are dimensioned to partly nest within said hitching arrangement, and when nested and said locking member is moved to the locked position and retained by said lower rail, then the implement is hitched to the heavy duty machinery.

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16 O S16. The assembly of claim 15, wherein the hitching arrangement is provided O by a hitch plate having the upper rail and the lower rail.

17. The assembly of claim 15 or claim 16, wherein the locking member has a guide plate having an upper end attached to the locking cylinder and a lower 0 end from which extends locking pins that are receivable within apertures in o the lower rail.

18. The assembly of claim 17, wherein the guide plate has elongate slots, 0 10 retaining guide members extend from the spacer plate through the slots and prevent the guide plate from moving other than parallel with the spacer plate.

19. The assembly of claim 18, wherein each load transmission plate has a first aperture for receiving a pin for pivotally connecting each load transmission plate to the hydraulic boom, and each load transmission plate has a second aperture for receiving a pin for pivotally connecting the load transmission plates to one or more hydraulic arm cylinders.

An apparatus for cutting or digging through a substrate substantially as hereinbefore described with reference to any one of figures 1 to

21. A quick hitch assembly for attaching an implement to heavy duty machinery substantially as hereinbefore described with reference to figures 1 2, 4, 9, 10 and 11. DATED this 15th day of November 2004 Al Hydraulic Cylinder Services Pty Ltd By Their Patent Attorneys CULLEN CO.