Single arm support apparatus for a rockwheel

Abstract

A single arm support apparatus for a rockwheel for excavating a trench through difficult materials, including rock. The rock cutting attachment includes a frame assembly which supports a cutting wheel in a manner that permits it to be inserted into the ground to approximately the radius of the wheel. The cutting wheel mounts to a shaft that is supported by bearings on a single side of the wheel, and is rotationally driven by a hydraulic motor. Additional structure mounted on the frame provides depth control.

Description

CROSS REFERENCE TO RELATED APPLICATIONS

[0001] Not applicable.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

[0002] Not applicable.

REFERENCE TO MICROFICHE APPENDIX

[0003] Not applicable.

BACKGROUND OF THE INVENTION

[0004] 1. Field of the Invention

[0005] The present invention relates generally to excavation machines. Specifically, the present invention relates to a single arm support apparatus for a rockwheel.

[0006] 2. Description of Related Art

[0007] As can be seen by reference to the following U.S. Pat. Nos. 2,420,836; 4,553,522; 4,762,371; 5,203,615; and 5,657,803, the prior art is replete with myriad and diverse single arm support apparatus for a rockwheel.

[0008] While all of the aforementioned prior art constructions are more than adequate for the basic purpose and function for which they have been specifically designed, they are uniformly deficient with respect to their failure to provide a simple, efficient and practical single arm support apparatus for a rockwheel.

[0009] As a consequence of the foregoing situation, there has existed a longstanding need for a new and improved single arm support apparatus for a rockwheel, and the provision of such a construction is a stated objective of the present invention.

BRIEF SUMMARY OF THE INVENTION

[0010] The present invention relates to a single arm support apparatus for a rockwheel which is utilized to excavate material and form an open trench, typically in soil conditions ranging from hard compacted abrasive soils, to loose soils with a significant percentage of stones, to solid stone or concrete. This trench is formed by hard, cutting teeth mounted on the outer circumference of a relatively thin disc/wheel that is rotated with sufficient torque to propel the teeth through the material being cut. At the same time it is forced down into engagement with the ground so that the lowest portion of the wheel defines the bottom of the trench. The wheel is propelled along the ground surface to extend formation of the trench the desired length and profile.

[0011] The desired trench is typically being formed to allow installation of water lines, gas lines, or electrical lines of various types and thus the width of the trench is typically much less than the desired depth of the trench. The maximum depth is typically approximately equal to the radius of the wheel.

[0012] The critical capabilities of the apparatus include:

[0013] 1. ability to set and maintain the desired trench depth;

[0014] 2. ability to achieve sufficient torque and speed to excavate at an acceptable rate; and

[0015] 3. ability to withstand the substantial loads inherent to the application of inserting a relatively thin wheel into the ground forming a trench in hard compacted soil or rock.

[0016] Machines providing these capabilities have been available for several years. Machines of this sort manufactured and sold by Vermeer Mfg. Co. typically comprise a prime mover of various sorts, including track mounted or rubber tired vehicles equipped with what is known as a rock cutter or rock wheel attachment. They have been marketed by Vermeer as RW6540, RW4147, RW5536, RW6540, RW7548, RW8536, RW8540, RW8554, RW855. The attachment is comprised of:

[0017] 1. a welded frame designed to couple to the prime mover and support rotary mounts for the wheel on both sides;

[0018] 2. one rotary mount typically being a hydraulic motor or gearbox;

[0019] 3. the other rotary mount being a bearing;

[0020] 4. the wheel with cutting teeth;

[0021] 5. a shaft or rotary support member passing from one rotary support to the next;

[0022] 6. shielding to direct the cuttings and shield moving components;

[0023] 7. hydraulic system to raise and lower the attachment; and

[0024] 8. stabilizers on both the left and right side to control the lowered position of the attachment to allow control of the depth of the trench.

[0025] The significant forces inherent in this application have always required a design as this including support on both sides of the wheel. There are inherent difficulties associated with these attachments related to this need to support the wheel on both sides including:

[0026] 1. difficulties in manufacturing the frame in a manner to assure proper alignment of the rotary mounts for the wheel;

[0027] 2. difficulties in assembling the wheels to the frame associated with the rotary mounts on both sides; and

[0028] 3. difficulties in maintenance if the wheel needs to be removed, in that at least one rotary mount needs to be removed.

[0029] The mounting of rotating discs/wheels has been accomplished in a variety of manners. Examples of various mounts can be seen in U.S. Pat. No. 2,420,836 to Nelson; U.S. Pat. No. 4,553,622 to De Cortanze; U.S. Pat. No. 5,657,803 to Kappel; U.S. Pat. No. 4,762,371 to Lupton; and U.S. Pat. No. 4,230,372 to Marten.

[0030] In the patent to Nelson a thin disc, saw blade, is mounted to a shaft that is supported on bearings on a single side of the disc. This application includes high rotational speed of the disc and relatively low forces being applied to the cutting disc, forces required for proper function of the saw blade.

[0031] The patent to DeCortanze discloses a driving wheel for a motorcycle is mounted on a shaft again supported on bearings on a single side of the wheel. Here again the application includes relatively high rotational speeds and relatively low forces as the force is limited by the coefficient of friction between the tire and the road surface.

[0032] The patent to Kappel discloses a cutting wheel of a stump cutter that is mounted on a shaft of a gearbox again supported by the bearings of the gearbox on a single side of the wheel. This application involves relatively high speeds, with a relatively small outer diameter wheel.

[0033] The patent to Lupton discloses a cutting wheel, a road planar, that is mounted on a shaft that is supported on both sides of the wheel. This application subjects the frame to forces required to cut pavement with cutting teeth mounted on the circumference of a wheel. This design will have similar difficulties as described as inherent with the rock wheel attachments.

[0034] The patent to Marten discloses a pair of excavating wheels mounted to a single shaft and utilized to excavate in a manner similar to the present invention.

SUMMARY OF THE INVENTION

[0035] The present invention relates generally to a trencher having a prime mover and a rock cutting attachment for excavating a trench through difficult materials including rock. The rock cutting attachment includes a frame assembly which supports a cutting wheel in a manner that permits it to be inserted into the ground to approximately the radius of the wheel. The cutting wheel mounts to a shaft that is supported by bearings on a single side of the wheel, and is rotationally driven by a hydraulic motor. Additional structure mounted on the frame provides depth control.

[0036] An object of the present invention is to provide a mounting arrangement for an excavating wheel that provides for simplified components in order to reduce manufacturing complexity.

[0037] A further object of the present invention is to provide a mounting arrangement for an excavating wheel that provides for simplified assembly of the wheel to its support structure.

[0038] A still further object of the present invention is to provide a mounting arrangement for an excavating wheel that provides for simplified maintenance.

[0039] Other objects, advantages, and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0040] FIG. 1 is a left side perspective view of a preferred embodiment of the excavating wheel attachment mounted onto a prime mover;

[0041] FIG. 2 is a left side perspective view of the same embodiment of the excavating wheel shown in FIG. 1 with some of the shielding removed;

[0042] FIG. 3 is a right side perspective view of the same embodiment of the excavating wheel shown in FIG. 1 with some of the shielding removed;

[0043] FIG. 4 is a perspective view of the main frame assembly;

[0044] FIG. 5 is a perspective view of the wheel support shaft assembly;

[0045] FIG. 6 is a perspective breakdown of the components of the wheel support shaft assembly;

[0046] FIG. 7 is a side elevational view of the lift assembly;

[0047] FIG. 8 is a perspective view of the stabilizer assembly;

[0048] FIG. 9 is a perspective view of the excavating wheel assembly with portions thereof exploded away; and

[0049] FIG. 10 is a perspective view of the motor mounting.

DETAILED DESCRIPTION OF THE INVENTION

[0050] Referring to the drawings, wherein like reference numerals designate identical or similar parts throughout the views, FIG. 1 shows a prime mover 10 and a preferred embodiment of the excavating wheel attachment 100. The prime mover 10 typically comprises an engine and drive line capable of propelling the assembly along the ground surface to transport between excavations and to propel the excavating wheel through the ground to extend the trench. The embodiment illustrated utilizes rubber tires for ground engagement. Tracks are also commonly used for ground engagement. The prime mover also typically includes a hydraulic system that is capable of providing power to a motor on the excavating wheel attachment 100 to rotate the wheel and of providing controlled pressure circuits to raise and position the excavating wheel attachment 100.

[0051] The excavating wheel attachment 100 typically attaches to the prime mover 10 at a mounting plate. Hydraulic lines transfer the hydraulic fluid from the circuits on the prime mover 10 to the appropriate components of the excavating wheel attachment 100.

[0052] Referring now to FIGS. 2 and 3, a preferred embodiment of the excavating wheel attachment 100 is illustrated. The attachment is comprised of a mounting plate 110, main frame assembly 130, lift assembly 170, stabilizer assembly 180, excavating wheel assembly 200 and drive motor 240.

[0053] The mounting plate 110 (FIG. 2) includes a surface 112 that mates with the prime mover. Fasteners 114 secure the attachment to the prime mover 10. Main frame pivot supports 118 and lift cylinder pivot support 120 are fixedly attached to the opposite side 116 of plate 110. Securing means cooperate with these pivot supports 118, in the preferred embodiment pivot pins 122 secure the main frame assembly 130 to the mounting plate 110 and a pivot pin 124 secures a lift cylinder 172 to the mounting plate 110.

[0054] Referring now to FIG. 4, the main frame assembly 130 is illustrated. The main frame assembly 130 is comprised of a main frame 132 and a wheel support shaft assembly 150.

[0055] The main frame 132 includes a pivot axis 134 on a first distal end 136 defined in this embodiment by a through-hole 138. A wheel mount plate 142 is at the opposite end of the main frame 132. A stabilizer support pivot 144 is defined in this embodiment by aligned holes in stabilizer mounting tabs 140 and main structural member 141. The main frame 132 further includes shielding structure 148 (shown in dashed lines in FIGS. 2, 3 and 4) which is adapted to cooperate with the excavating wheel.

[0056] The wheel support shaft assembly 150 is secured to the wheel mount plate 142 of the main frame 132 by fasteners 146.

[0057] Referring now to FIGS. 5 and 6, the wheel support shaft assembly 150 is illustrated. This assembly is comprised of housing 152, wheel mount shaft 154, wheel bearing assemblies 156, dust seal 157, oil seal 153, bearing clamp nut 159, and o-ring seal 158. Wheel mount shaft 154 is supported by the two wheel bearing assemblies 156 while bearing clamp nut 159 restrains those components in the housing 152. Mating surface 162 of the housing 152 mates to the wheel mount plate 142 of the main structural member 140 shown in FIG. 4 and the two are connected with fasteners 146.

[0058] Referring now to FIG. 7, the lift assembly 170 is illustrated. This assembly is comprised of a lift cylinder 172, cylinder pin 124 and cylinder pin 174. The cylinder 172 is attached at a first end to the mounting plate 110 at the lift cylinder pivot support 120 with cylinder pin 124 and at the opposite end to the main structural member 141 with cylinder pin 174 through an opening in member 141a. Hydraulic hose 176 is connected to the cylinder 172 and at the other end to a hydraulic system that is part of the prime mover 10.

[0059] Referring now to FIG. 8 the stabilizer assembly 180 is illustrated. This assembly is mounted onto the main frame 132 (FIG. 2) and is comprised of stabilizer arm mount pins 182, stabilizer arms 184, cylinders 186, stabilizer cylinder mount pins 188 and hydraulic hoses 190. The stabilizer arms are secured to the main frame 132 by the mount pins 182 in a manner such that they can rotate between a lowered position where the foot 194 (see FIGS. 2 and 8) will limit the depth of penetration of the excavating wheel to the minimum controlled depth and an upper position where the foot 194 will limit the depth of penetration to the maximum controlled depth, which is slightly less than the radius of the excavating wheel. Cylinders 186 are connected to mounting tabs 140 on one end and to the stabilizer arms 184 on the other end with pins 188. Extension or retraction of these cylinders controls the position of the stabilizer arms and thus the depth of the excavation. Hoses 190 transfer hydraulic oil with controlled flow and pressure from the prime mover 10.

[0060] Referring now to FIG. 9 the excavating wheel assembly 200 is illustrated. This assembly 200 is comprised of the wheel 210 and cutter assemblies 220. The cutter assemblies 220 consist of pockets 222 and teeth 224. The cutter assemblies 220 are secured to the wheel 210 with fasteners 226 that engage with the pattern of holes 216 in the wheel 210. Assembly 200 is attached to hub 154 by fasteners 230 into threaded holes 164 as shown in FIGS. 3 and 9.

[0061] The wheel 210 includes an axis of rotation 212 that is defined by the center of pilot hole 214. A pattern of holes 216 on the outer circumference of the wheel 210 needs to be concentric with the pilot hole 214 for proper performance. A second pattern of holes 218 is arranged in a bolt pattern such that they are also concentric with the pilot hole 214 and designed to mate with the pattern of holes 164 in the wheel mount shaft 154 (FIG. 6). Fasteners 230 (FIG. 9) secure the excavating wheel assembly 200 to the wheel mount shaft 154.

[0062] The wheel mount shaft 154 is supported in the housing 152 as shown in FIG.6. The wheel 210 is secured on one end as shown in FIG. 9. The opposite end of the wheel shaft 154 includes an internal spline connection 155 shown in FIG. 10. As seen in FIG. 10 a drive motor 240 includes an externally splined shaft 232 that engages with the internal spline 155 of the wheel mount shaft 154. The drive motor 240 is secured to the housing 152 by fasteners 234 thus engaging the mating splines and enabling the drive motor 240 to control rotation of the wheel assembly 200.

[0063] Referring again to FIG. 2, the operation of the attachment is described. Hydraulic fluid is provided to the drive motor 240 from the prime mover 10, typically with the main frame assembly 130 pivoted into its raised position by lift assembly 170 (FIGS. 2 and 7). This will cause the wheel assembly 200 to rotate. As it is rotating, it is lowered into engagement with the ground 12 which results in formation of the trench. Wheel assembly 200 continues to progress into the ground 12 until the shoe 194 of the stabilizer assembly 180 contacts the ground 12, thus controlling the depth of the trench. The prime mover 10 is now propelled forward (to the left as shown in FIG. 2) thus moving the excavating wheel attachment 100 parallel to the ground 12 extending the length of the trench.

[0064] Advantages of this invention include the fact that the support for the excavating wheel assembly 200 comes solely from the wheel support shaft assembly 150, located on a single side of the wheel. The wheel support shaft assembly 150 is of a size and shape that it can be easily manufactured within close dimensional tolerances. Since the support is provided with this single component the main frame 132 is also much easier to manufacture as there are no critical alignment features related to supports for the excavating wheel assembly on both sides. An additional advantage is apparent when the excavating wheel assembly 200 is installed as it need to mate up to the wheel mount shaft 154 only.

[0065] Accordingly, it will be appreciated that the preferred embodiment shown herein accomplishes all of the aforementioned objects. Obviously many modifications and variations of the present invention are possible in view of the above teachings. It is therefore to be understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically described.

Claims

1. An excavation apparatus for forming a trench including:

a prime mover; and

an excavation wheel attachment operatively attached to said prime mover, wherein said excavation wheel attachment comprises:

a support structure having a first end and a second end, said support structure being operably pivotally mounted on said one end thereof to said prime mover for movement between a lowered position and a raised position;

a shaft operably rotatably attached to the other end of said support structure;

an excavation wheel assembly operatively attached to said shaft on one side of said support structure whereby said support structure provides the entire support of said excavation wheel assembly, said excavation wheel assembly including cutting teeth mounted on the outer circumference thereof for defining an effective cutting diameter adapted for cutting hard soils, wherein the effective cutting diameter is at least five times the diameter of the shaft mounting bearings and the excavation wheel assembly; and

a motor operatively attached to said shaft of a size capable of rotating the shaft and excavation wheel assembly in an operative mode of between 40 and 200 revolutions per minute.

2. The apparatus of claim 1 further comprising a pair of shaft mounting bearings operably disposed on said shaft for reducing friction during the rotation of said shaft with respect to said support structure.

3. The apparatus of claim 1 further comprising a hydraulic cylinder operably pivotally attached to said prime mover and to said support structure for moving the support structure between said lowered and raised positions thereof.

4. The apparatus of claim 1 further comprising a ground engaging shoe operatively attached to said support structure for determining the lowered position of the excavation wheel assembly.

5. The apparatus of claim 4 further comprising an adjusting device for adjustably moving the position of said shoe with respect to said support structure.

6. The apparatus of claim 4 further comprising a hydraulic cylinder operatively attached said support structure and said shoe for adjustably moving the position of said shoe with respect to said support structure, whereby the distance that the excavation wheel assembly can extend into the ground can be adjustably predetermined.

7. A method for using an excavation apparatus for forming a trench, said apparatus comprising:

a prime mover; and

an excavation wheel attachment operatively attached to said prime mover, wherein said excavation wheel attachment comprises:

a support structure having a first end and a second end, said support structure being operably pivotally mounted on said one end thereof to said prime mover for movement between a lowered position and a raised position;

a shaft operably rotatably attached to the other end of said support structure;

an excavation wheel assembly operatively attached to said shaft on one side of said support structure whereby said support structure provides the entire support of said excavation wheel assembly, said excavation wheel assembly including cutting teeth mounted on the outer circumference thereof for defining an effective cutting diameter adapted for cutting hard soils, wherein the effective cutting diameter is at least five times the diameter of the shaft mounting bearings and the excavation wheel assembly; said method comprising:

rotating said excavation wheel assembly between 40 and 200 revolutions per minute; and

moving said support structure toward said lowered position to cause said excavation wheel assembly to dig a trench in the ground.

8. A rockwheel drive, support and position control structure comprising:

a rockwheel adapted with a mounting hub configured to mount onto a flange on a single side;

a rockwheel shaft supported in a cantilvered manner by at least two shaft mounting bearings including a flange on one side and a drive coupling on the opposite side;

a driving motor which engages to the drive coupling of the rockwheel shaft;

a single support arm configured to support the shaft mounting bearings, and the driving motor on a first distal end, and main mounting bearings on a second distal end wherein the main mounting bearings allow the support arm to pivot between a first raised position and a second lowered position;

a support structure which provides support for the main mounting bearings;

a single positioning cylinder which connects on one end to the support arm between the first and second distal ends and on the opposite end to the support structure wherein the cylinder is capable of moving the rockwheel between the raised position and the lowered position; and

a separate cutting depth control structure attached to the support arm which includes a ground engaging shoe capable of adjustably defining the lowered position such that it is controlled relative to the ground wherein the depth control structure comprises two three-bar links, one positioned on each side of the support arm with a common axis of rotation that is located between the first and second end of the support arm.

9. An excavation apparatus for forming a trench including:

a prime mover; and

an excavation wheel attachment operatively attached to said prime mover, wherein said excavation wheel attachment comprises:

a support structure mounted on a pivot in a manner to be moved between a lowered position and a raised position;

a shaft supported by the support structure in a cantilevered manner by at least two shaft mounting bearings; and

an excavation wheel assembly including cutting teeth mounted on its outer circumference defining an effective cutting diameter adapted for cutting hard soils wherein the effective cutting diameter is at least five times the diameter of the shaft mounting bearings and is disposed for rotation at between 40 and 200 revolutions per minute.