1111111111111111 IIIIII IIIII 11111 1111111111 111111111111111 11111 1111111111 1111111111 11111111
`US 20020192025Al
`
`(19) United States
`(12) Patent Application Publication
`Johnson
`
`(10) Pub. No.: US 2002/0192025 Al
`Dec. 19, 2002
`(43) Pub. Date:
`
`(54) CUTTING MACHINE WITH FLYWHEEL
`GEARBOX DESIGN AND METHOD FOR USE
`
`(57)
`
`ABSTRACT
`
`(76)
`
`Inventor: H. Matthew Johnson, Shermansdale,
`PA(US)
`
`Correspondence Address:
`MCNEES, WALLACE & NURICK
`100 PINE STREET
`P.O. BOX 1166
`HARRISBURG, PA 17108-1166 (US)
`
`(21)
`
`Appl. No.:
`
`10/143,147
`
`(22)
`
`Filed:
`
`May 10, 2002
`
`Related U.S. Application Data
`
`(60)
`
`Provisional application No. 60/293,567, filed on May
`25, 2001.
`
`Publication Classification
`
`Int. Cl.7 .............................. E21C 25/00; EOlC 7/06
`(51)
`(52) U.S. Cl.
`................................................. 404/75; 299/78
`
`A cutting machine for cutting depressions in a road surface.
`The cutting machine includes a rotatable cutting drum
`connected with a drive device for rotating the cutting drum
`and an engaging device for moving the cutting drum out of
`and into contact with the road surface. The drive device
`includes a gear box with a flywheel located on the input side
`of the gear box and the cutting drum comprises a plurality
`of cutting teeth, the teeth removably retained to the cutting
`drum to effectively cut the road surface and includes a means
`for anchoring a tooth shank to a tooth holder permanently
`affixed to said cutting drum. A power unit that moves the
`cutting drum along the road surface is provided with a
`detector for continuously detecting a distance that the cut(cid:173)
`ting drum is moved by the power unit and for generating a
`signal indicative of the distance moved. An electronic con(cid:173)
`troller, responsive to the signal, electronically controls the
`engaging device so that the cutting drum moves out of and
`into contact with the road surface in accordance with the
`distance that the cutting drum moves along the road surface
`and a specified dimensional profile of the depressions which
`are stored in the electronic controller. The movement of the
`cutting drum cuts depressions in the road.
`
`59
`
`60
`
`53 43
`
`83
`
`62
`
`CATERPILLAR EXHIBIT 1044
`CATERPILLAR v. WIRTGEN
`IPR2018-01091
`
`Page 1 of 19
`
`

`

`Patent Application Publication Dec. 19, 2002 Sheet 1 of 9
`
`US 2002/0192025 Al
`
`LO
`l()
`
`Page 2 of 19
`
`

`

`Patent Application Publication Dec. 19, 2002 Sheet 2 of 9
`
`US 2002/0192025 Al
`
`0
`
`{O
`0
`0
`
`r---
`,
`I ='
`
`------7
`I
`o o o o o
`I
`:
`\ _____ _J
`
`l O O O
`
`LO
`in
`
`Page 3 of 19
`
`

`

`Patent Application Publication Dec. 19, 2002 Sheet 3 of 9
`
`US 2002/0192025 Al
`
`I
`I
`L ____ _J
`
`Page 4 of 19
`
`

`

`Patent Application Publication Dec. 19, 2002 Sheet 4 of 9
`
`US 2002/0192025 Al
`
`7
`
`9
`
`85
`
`62
`
`Page 5 of 19
`
`

`

`Patent Application Publication Dec. 19, 2002 Sheet 5 of 9
`
`US 2002/0192025 Al
`
`0 c:o
`
`..... \
`
`0 co C
`
`Page 6 of 19
`
`

`

`Patent Application Publication Dec. 19, 2002 Sheet 6 of 9
`
`US 2002/0192025 Al
`
`Page 7 of 19
`
`

`

`Patent Application Publication Dec. 19, 2002 Sheet 7 of 9
`
`US 2002/0192025 Al
`
`I
`r--,
`I
`I
`I
`I
`I
`I
`I
`I
`I
`I
`I
`I
`I
`I
`I
`I
`I
`I
`I
`L __ _J
`I
`I
`
`I
`I
`I
`I r--1
`r'
`
`7
`I
`I
`
`I
`I
`___ _J
`I
`I
`
`~
`~
`~
`
`Page 8 of 19
`
`

`

`Patent Application Publication Dec. 19, 2002 Sheet 8 of 9
`
`US 2002/0192025 Al
`
`Page 9 of 19
`
`

`

`Patent Application Publication Dec. 19, 2002 Sheet 9 of 9
`
`US 2002/0192025 Al
`
`0
`(0
`
`0
`
`Page 10 of 19
`
`

`

`US 2002/0192025 Al
`
`Dec. 19, 2002
`
`1
`
`CUTTING MACHINE WITH FLYWHEEL
`GEARBOX DESIGN AND METHOD FOR USE
`
`CROSS REFERENCE TO RELATED
`APPLICATIONS
`
`[0001] This application claims the benefit of U.S. Provi(cid:173)
`sional Application No. 60/293,567 filed May 25, 2001.
`
`FIELD OF THE INVENTION
`
`[0002] This invention relates to a cutting tool for cutting a
`series of depressions along surfaces of roadways, and more
`particularly to a cutting tool utilizing a flywheel gearbox
`design.
`
`BACKGROUND OF THE INVENTION
`
`[0003] As motor vehicle operators become fatigued or
`distracted, the possibility of the vehicle drifting off the road
`or over the center line and into the opposite lane of traffic
`increases, either of which can potentially lead to disastrous
`results. To minimize this occurrence, a series of depressions
`are cut along the shoulders or center line of the roadway,
`referred to as ground in rumble strips. The purpose of the
`rumble strip is to alert drivers when they have drifted outside
`their traffic lane by creating a sound and causing vibration of
`the vehicle as the vehicle tires travel over the depressions.
`
`[0004] Differing designs of road surface grinders/cutting
`machines which use a cutting drum or drums to cut indi(cid:173)
`vidual depressions have heretofore been devised. In older
`designs, cutting drums have been attached to or made part of
`a multipurpose power unit such as a tractor or skidsteer
`loader. The tractor or skidsteer loader is used to move the
`cutting drum along the surface of the road and to provide any
`necessary utilities thereto, such as electricity or hydraulic
`fluid. More recent designs have attached the cutting drum to
`a vehicle frame designed solely for use with the cutting
`drum. With either design, the cutting drum is lowered into
`contact with the road surface to cut the depression.
`
`[0005] Current practice cutting machines use a variety of
`methods for engaging and disengaging the cutting drum into
`the road surface to cut the depression and for repositioning
`the cutting drum for the next cut. One method of raising and
`lowering the cutting drum requires an operator to manually
`control a hydraulic cylinder which is connected to the
`cutting drum. A problem with this method is that it is difficult
`for the operator to move the cylinder controls quickly
`enough to achieve a sufficient production rate ( defined as
`forward feet per minute) while cycling the cutter.
`
`[0006] An example of such a manually operated system is
`disclosed in U.S. Pat. No. 5,094,565 which utilizes a plu(cid:173)
`rality of manually controlled cutting drums to cut a series of
`depressions at one time. The production rate is increased by
`using the plurality of cutting drums, which are lowered onto
`the road surface to cut the depressions while the power unit
`is stationary. After the cut is complete, the cutting drums are
`raised and the power unit moves to the next location. Since
`there is not a continuous forward movement of the power
`unit, additional time is required for raising and lowering the
`cutting drums. Additionally, since the required sizing ( depth,
`width, length, and radius of curvature of each depression) is
`specified depending on the task at hand, appropriately sized
`cutting drums must be used in order to meet the required
`
`dimensional s1zmg of the depressions. Thus, if different
`depression sizes are required, the cutting drums may have to
`be replaced.
`[0007]
`In order to overcome some of the problems with
`the manual systems, automated means for raising and low(cid:173)
`ering the cutting drum have been developed. Such means
`include rigidly connecting the cutting drums (1) to an
`eccentric wheel which rolls over the road surface or (2) to a
`cam and lever system. In each of these automated systems,
`the cutting drum is automatically raised and lowered as the
`power unit moves forward due, respectively, to the rotation
`of the eccentric wheel and the action of the cam and levers.
`These systems are an improvement over the manually oper(cid:173)
`ated systems since the production rate of making depres(cid:173)
`sions is increased because the cutting drum cuts as the power
`unit moves forward.
`[0008]
`In order to achieve higher production while cycling
`the cutter, the cutter must maintain a minimum cutter rpm.
`To achieve the desired product, i.e. a road surface depression
`of a specified dimension, the cutter must make at least one
`complete revolution while cutting each rumble strip depres(cid:173)
`sion. Less than one full revolution of the cutter produces an
`incomplete or dimensionally defective cut. In particular, the
`repeating cycling of the cutter against the road surface
`produces repeating torque peaks as the cutter initially makes
`contact with the road surface that must be overcome in order
`to produce the required full revolution of the cutter per cut.
`[0009] Therefore, the maximum production rate of any
`cutting machine is limited by the amount of time required for
`the cutting drum to complete each cut. In addition, current
`systems can not meet maximum production rates because of
`inherent limitations above and beyond the cutting time
`required by the cutting drum to complete its cut, such as
`those imposed by the mechanical arrangements used to
`control cutter rpm and the vertical motion of the grinding
`drum.
`[0010] U.S. Pat. No. 5,415,495, assigned to the assignee of
`the present invention, describes an electronic controller
`responsive to a signal indicative of the forward distance
`traveled by the cutter. The controller electronically controls
`an engaging device so that the cutting drum moves out of
`and into contact with the road surface in accordance with the
`distance that the cutting drum moves along the road surface
`and a specified dimensional profile of the depression, which
`are stored in the electronic controller.
`[0011] One problem with this and other current practice
`hydrostatic drives is the elasticity of hydraulic systems. This
`problem causes the cutter rpm to drop off as much as 50%
`during the cut. In order to maintain the required minimum
`one full cutter rotation per cut, forward speed must be
`reduced, with resulting decrease in production.
`[0012] One way to achieve greater production is to
`increase the cutter rotational speed so that when it slows
`down on contact with the road surface it effectively still
`maintains the necessary revolutions per minute to permit at
`least one full revolution prior to the next cycle. However, in
`current practice, the cutting teeth are held in their holders
`solely with springs that create friction. While the springs
`protect the tooth holder from wear and permit tooth rotation,
`when cutter rotational speed exceeds about 600 rpm, it is
`difficult to retain the cutting teeth in their holders, even using
`retaining springs.
`
`Page 11 of 19
`
`

`

`US 2002/0192025 Al
`
`Dec. 19, 2002
`
`2
`
`[0013] Other attempts to counteract the cutting drum slow(cid:173)
`down problem include adding torque to the hydrostatic
`system and increasing kinetic energy through increasing the
`mass of the cutting drum. For example, lead is added to the
`interior of the cutting drum to increase its mass and reduce
`the elasticity inherent in a hydraulic system.
`
`[0019] The present invention also provides a cutting
`machine which electronically controls the vertical move(cid:173)
`ment of the cutting drum into and out of contact with a road
`surface, thereby allowing a power unit and the cutting drum
`to continuously progress forward as the cutting drum cuts
`depressions.
`
`[0014]
`It is often the case that the number of depressions
`in a given rumble strip and/or the size of the depressions in
`a given rumble strip are different depending on the job site.
`Accordingly, in order to accommodate these changes, cur(cid:173)
`rent practice non-electronic controller systems require the
`replacement of the cutting drum and/or a complete change of
`the mechanical control mechanism ( eccentric wheel, cam/
`lever) in order to achieve the required depression sizing.
`Such reconfiguring of the cutting machine is time consum(cid:173)
`ing and costly, making an electronically controlled unit
`desirable. In addition, it is also desirable to make these cuts
`as rapidly as possible.
`
`[0015] Thus, there is a continuous need for improved
`designs for cutting tools to increase operating efficiencies. In
`particular, there remains a need to maintain cutter rpm
`throughout the repeating cutting cycle while encountering
`varying road surface conditions. The present invention ful(cid:173)
`fills this need, and further provides related advantages.
`
`SUMMARY OF THE INVENTION
`
`[0016] The present invention provides a cutting machine
`for cutting depressions in a road surface. The cutting
`machine includes a rotatable cutting drum connected with a
`drive device for rotating the cutting drum and an engaging
`device for moving the cutting drum out of and into contact
`with the road surface. The drive device includes a gear box
`with a flywheel located on the input side of the gear box,
`while the cutting drum comprises a plurality of cutting teeth,
`the teeth removably positioned to the cutting drum to
`effectively cut the road surface, and includes a means for
`anchoring a tooth shank to a tooth holder permanently
`affixed to the cutting drum.
`
`[0017]
`In one form, a power unit that moves the cutting
`drum along the road surface is provided with a detector for
`continuously detecting a distance that the cutting drum is
`moved by the power unit and for generating a signal
`indicative of the distance moved. An electronic controller,
`responsive to the signal, electronically controls the engaging
`device so that the cutting drum moves out of and into contact
`with the road surface in accordance with the distance that the
`cutting drum moves along the road surface and a specified
`dimensional profile of the depressions which are stored in
`the electronic controller. The movement of the cutting drum
`cuts depressions in the road. An optional means is provided
`to prevent rear end skidding which can cause cutting drum
`tracking problems.
`
`[0018] The present invention provides means for elec(cid:173)
`tronically controlling the vertical motion of the cutting drum
`of a cutting machine and automatically adjusting the cutting
`drum to align with the contours of the road surface as it
`travels over the road surface. Both of these features allow
`the cutting process to progress more quickly and accurately
`than previous road cutting machines because they impose no
`limitations on the depression forming production rate
`beyond the cutting time required by the cutting drum.
`
`[0020] The present invention further provides a cutting
`drum machine which maintains cutter rotational speed above
`a minimum speed required throughout the repeating cutting
`cycle as it encounters varying road surface conditions.
`
`[0021] The cutting machine for cutting depressions in a
`road surface as set forth in the present invention includes a
`rotatable cutting drum; a plurality of cutting teeth, the teeth
`removably retained to the cutting drum to effectively cut the
`road surface; a drive system for rotating the cutting drum
`and maintaining the rotational speed to provide at least one
`full revolution at a pre-selected depth of cut, wherein the
`drive system includes a gear box comprising a flywheel on
`an input side of the gearbox; engaging means for moving the
`cutting drum out of and into contact with the road surface;
`means for moving the cutting drum along the road surface;
`means for continuously detecting-the distance that the cut(cid:173)
`ting drum is moved by the moving means and for generating
`a signal indicative of the distance moved; electronic control
`means, responsive to the signal, for electronically control(cid:173)
`ling the engaging means to move the cutting drum out of and
`into contact with the road surface in accordance with the
`distance that the cutting drum moves along the road surface
`and a specified dimensional profile of the depressions which
`are stored in the electronic control means so that the depres(cid:173)
`sions are cut, and means for continuously aligning the
`cutting drum with a slope of the road surface.
`
`[0022] The invention optionally provides electronic feed(cid:173)
`back relative to movements of the cutting drum, which
`feedback can be processed and displayed to the operator
`periodically, thereby alerting him as to whether or not the
`cutting drum is operating properly, that is, has sufficient time
`to complete the cutting cycle in relation to the forward speed
`of the entire cutting machine.
`
`[0023] The invention utilizes as much weight a possible to
`keep the cutting drum engaged with the road surface.
`
`[0024] The invention also provides means for both elec(cid:173)
`tronically and mechanically adjusting the cutting tool to vary
`both the depth and width of the depressions consistently
`across the length of the rumble strip as well as to vary the
`depth and width of the depressions across the length of the
`rumble strip, as field conditions or job specifications require.
`
`[0025] An advantage of the present invention is that the
`flywheel boosts the torque applied to the cutting drum to
`keep it from slowing down as the cutting drum engages the
`road surface during a cut. This allows the mobile power unit
`to travel at a higher rate of speed, thereby allowing the
`cutting drum to make more cuts in a unit of time.
`
`[0026] Another advantage of the present invention is that
`the cutting teeth design of the present invention are retained
`in their holders at the rotational speed of the cutting drum as
`the cuts are made.
`
`[0027] Other objects, features and advantages of the
`present invention will become apparent to those skilled in
`the art from the following detailed description and drawings.
`
`Page 12 of 19
`
`

`

`US 2002/0192025 Al
`
`Dec. 19, 2002
`
`3
`
`It should be understood, however, that the detailed descrip(cid:173)
`tion and specific examples, while indicating preferred
`embodiments of the present invention, are given by way of
`illustration and not limitation. Many changes and modifica(cid:173)
`tions within the scope of the present invention may be made
`without departing from the spirit thereof, and the invention
`includes all such modifications.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`[0028] Other objects, features and advantages of the
`present invention will become apparent from the following
`detailed description and accompanying drawings wherein:
`[0029] FIG. 1 is a right side view of the cutting machine;
`[0030] FIG. 2 is a right side view of the cutting apparatus;
`[0031] FIG. 3 is a front view of the cutting drum within
`the cutting machine housing as seen along the section line
`11-11 of FIG. 2;
`[0032] FIG. 4 is a front view of the front roller assembly;
`[0033] FIG. 5 is a cross-sectional view of a depression in
`a road surface.
`[0034] FIGS. 6a-6d are schematic representations of the
`gearbox;
`[0035] FIG. 7a is an oblique view of a cutting tooth with
`a retaining clip;
`[0036] FIG. 7b is an oblique view of a cutting tooth
`retained with a retaining clip in a tooth holder;
`[0037] FIG. 8 is a side view of a flat bed truck utilized as
`a power unit.
`
`DETAILED DESCRIPTION OF THE
`PREFERRED EMBODIMENTS
`
`[0038] Referring now to the drawings, and particularly to
`FIGS. 1-3, a cutting machine 1 includes a conventional
`cutting drum 3 contained within a housing 5 having a pair of
`opposed, substantially parallel, vertically extending side
`walls 7 and 9. In addition, the housing 5 contains front and
`rear sidewalls 11 and 13, and two top plates 15, 17 forming
`part of the top of the housing 5. Access to the inside of the
`housing 5 from the top is accomplished via a door (not
`shown). The bottom of housing 5 is completely open.
`[0039] Referring to FIGS. 2 and 3, cutting drum 3 is
`carried within housing 5 by two arm plates 21 and 23. The
`cutting drum 3 is attached to each of the arm plates 21 and
`23 through respective gear boxes 25 and 27. The gear boxes
`25 and 27 are each rigidly attached at one end thereof to the
`respective arm plate 21, 23, which allows the opposite end
`of the gear boxes 25 and 27 to rotate the cutting drum 3. The
`gear boxes may be attached to the inner side of respective
`arm plate 21, 23, as shown in FIG. 3, or to the outer side of
`respective arm plates 21, 23 to allow accommodation of a
`larger gear box, each gear box including an integral fly
`wheel.
`[0040] The cutting drum 3 is driven in a conventional
`manner by two hydraulic motors 29 and 31 which are
`respectively mounted through the arm plates 21 and 23 and
`into a respective gear box 25 and 27. Optionally, only a
`single gear box and motor can be utilized. The cutting drum
`3 is rotated, preferably in a counter clockwise/up cut direc-
`
`tion relative to a road surface, and uses hardened teeth, for
`example, milling/mining tungsten carbide tipped teeth to cut
`with. While a hydraulic motor driven system for the cutting
`drums has been described, other conventional direct or
`indirect drive systems can be used in lieu thereof, such as a
`belt driven or electric systems. To increase cutting drum
`inertial mass, the cutting drum may be filled with a high
`mass material, for example, lead.
`[0041] Power is provided to the gear box 25 by a hydraulic
`motor attached to an input shaft in the conventional manner.
`Referring now to FIGS. 6a-6d, each gear box 25, 27
`comprise a gear reducing gear box 160 with a flywheel 162
`of the present invention on the input side 164 or shaft of the
`gearbox, such as those produced by Power Engineering &
`Mfg., Ltd. of Waterloo, Iowa. and described in U.S. Pat.
`Nos. 4,281,560 and 4,270,410, incorporated by reference
`herein. The gearbox and fly wheel design criteria are set
`forth in a paper entitled Gear Box Design with Flywheel for
`Reduced Vibrations and Energy Savings by Saul Herscovici,
`published in 1980 by Society of Automotive Engineers, Inc.
`and incorporated herein by reference. The reducing gear box
`160 turns the output shaft which then transfers the power to
`rotate the cutting drum. The flywheel 162 provides an
`instantaneous increase in torque by increasing kinetic
`energy. The size of the flywheel 162 is determined by the
`amount of inertial torque required to overcome the peak
`torque value encountered as the cutting drum 3 first encoun(cid:173)
`ters the road surface during each cutting cycle to counteract
`the inertial forces of the road in slowing down the cutting
`drum. The flywheel size is determined by the amount of
`torque required to be provided, the torque to be released by
`the flywheel 162, the change in speed of the flywheel 162 in
`providing the additional torque and the reduction ratio
`provided by the reduction gear box 160 for a predetermined
`set of operating conditions. Inertial torque is released while
`the flywheel 162 is decreasing in speed. In a preferred
`embodiment, the gear box 25, 27 has a flywheel 162 that is
`about 6 inches to about 20 inches, preferably about 12 inches
`to about 14 inches in diameter and a width sufficient to add
`the desired amount of mass, currently about 2 inches to
`about 4 inches wide and operating at about 2,000 to about
`3,000 rpm. A typical gear reduction ratio provided by the
`reduction gear box can range from about 2:1 to about 6:1,
`with a reduction ratio of about 4: 1 being the most common
`and currently the best mode for practicing the present
`invention.
`
`[0042] Optionally, the flywheel 62 may include a slip
`clutch (not shown) for those applications which produce a
`peak torque value sufficient to abruptly stop the cutting drum
`3 and stall the gear box 25, 27. The slip clutch allows the
`kinetic energy stored in the flywheel 162 to be dissipated
`through friction without damaging the gears, flywheel or the
`cutting drum.
`
`[0043] Referring to FIGS. 7a-7b, each cutting tooth 170
`extends radially from cutting drum 3 and includes a shank
`172 and a cutting portion 174. Each cutting drum includes
`a plurality of cutting teeth 170 to provide cutting action
`against a road surface as cutting drum 3 rotates. The cutting
`portion 174 of each tooth is fabricated from a hardened
`material having excellent wear resistance, for example,
`tungsten carbide to increase service life, and has an effective
`cutting shape, for example, cylindrical with a cutting edge
`175. The cutting portion 174 further includes a stop portion
`
`Page 13 of 19
`
`

`

`US 2002/0192025 Al
`
`Dec. 19, 2002
`
`4
`
`176, for example, a shoulder, located at the cutting portion
`- shank junction. In a preferred embodiment, shank 172 is
`substantially round in cross section, although it may be oval,
`square, hexagonal or any other cross sectional shape per(cid:173)
`mitting it to be removably retained within a tooth holder
`180. In a preferred embodiment, the tooth shank 172 is
`partially covered by a spring 178 for additional retention
`within the tooth holder 180. The tooth shank 172 includes a
`retainer receiver 182 which is not covered by the optional
`spring 178, for example, a groove, hole, threads or slot for
`receiving a retainer 184, for example, a spring clip, mating
`threads or cotter pin which positively maintains each of
`cutting teeth 170 within their respective tooth holder 180,
`yet allows the cutting teeth to be easily removed from tooth
`holder 180 as they wear below dimensions required to
`provide an acceptable cut as determined by applicable
`specification requirements. To accommodate the retainer at
`the end of the tooth opposite the cutting edge, the overall
`tooth length has been increased. This overall lengthening of
`the tooth has the added effect of increasing the mass of the
`system and improves the ability of the teeth to remain in
`contact with the road surface.
`
`[0044] Each tooth holder 180 is permanently affixed to the
`cutting drum 3 using known methods, such as welding, and
`has an opening which in cross section mirrors that of the
`tooth to allow the spring covered tooth shank to be received
`in substantially intimate contact with the tooth holder 180.
`The shoulder 176 provides a positive stop for tooth 170
`against tooth holder 180. In a preferred embodiment, tooth
`holder 180 has an access port 186 to permit a retainer 84,
`such as a spring clip, to be affixed to the tooth shank retainer
`receiver 182, which may be for example a groove, thereby
`providing increased resistance to inadvertent removal or loss
`of tooth 170 as the rapidly rotating drum contacts the fixed
`and immovable road surface, thereby allowing for increased
`cutting drum rotational speed.
`
`[0045] Referring again to FIGS. 2 and 3, the arm plates
`21, 23 are interconnected at one end by the cutting drum 3
`and drive mechanism described above. The arm plates 21, 23
`are also interconnected by an I-beam 33 which is connected
`to each arm plate 21, 23 via bolts 35. The arm plates 21, 23
`are also connected at the rear of the housing 5 by a solid
`shaft 37 which pivots against bearings 39, each of which are
`contained in a tube 41. The tube 41 is welded to and made
`part of housing 5. The combination of the shaft 37, bearings
`39 and tube 41 allows the cutting drum 3 and arm plates 21,
`23 to pivot up and down. The up and down movement of
`cutting drum 3 allows it, and therefore the cutting teeth 170
`radially extending therefrom, to be engaged and disengaged
`with the road surface. Moreover, slots or opening 42 are
`provided in the side walls 7 and 9 to accommodate the
`movement of the I-beam 33. Additional slots or openings 44
`which extend from the bottom edges of side walls 7, 9 allow
`for movement of cutting drum 3 and drive mechanism
`without interference from the side walls 7, 9.
`
`[0046] The cutting mechanism, which includes cutting
`drum 3, arm plates 21, 23 and gear boxes 25, 27, is raised
`and lowered by a hydraulic cylinder 43 which is attached to
`the top plate 17 of the housing 5 by pillow block bearings 45
`and 47 and to the I-Beam 33 by an attachment device 49.
`The attachment device 49 includes two lug portions 49a, 49b
`each having a through opening 49c, 49d therein. The piston
`43a of hydraulic cylinder 43 has a through opening 43b
`
`which can be aligned with through openings 49c, 49d, such
`that a pin 51 passes through openings 49c, 49d and 43b,
`thereby connecting the hydraulic cylinder 43 to the cutting
`mechanism.
`
`[0047] Control of the hydraulic cylinder 43 is accom(cid:173)
`plished via an electronic servo valve 53. The electronic
`servo valve 53, which reacts more quickly than prior art
`electronic proportional valves used in prior designs, is
`activated to either raise or lower piston 43a of cylinder 43
`according to programmed instructions from a computer
`controller 55, FIG. 1. The computer controller 55 is pro(cid:173)
`grammed to precisely lower and raise the piston 43a to
`programmed depths as the cutting drum 3 advances across
`the road surface. The computer controller 55 receives elec(cid:173)
`tronic impulses which correspond to the distance traveled by
`the cutting machine 1 from a conventional wheel mounted
`encoder 57 which is disposed on a power unit 59, preferably
`the rear of the unit. The power unit 59 can be, for example,
`a motor vehicle such as a flat bed truck, a skidsteer loader
`or a tow tractor, and provides utilities such as electricity,
`water or hydraulics to the various components of the cutting
`machine 1. The power unit 59 also moves the entire cutting
`machine 1 along the road surface. The encoder 57 is also
`referred to as a rotary pulse generator and is, for example,
`produced under the name "Optical Incremental Encoder" by
`Allen-Bradley, Inc. of Manchester, N.H.
`
`[0048] As the forward speed of the power unit 59 changes,
`the rate of electronic impulses being received by the con(cid:173)
`troller 55 from encoder 57, correspondingly changes, so that
`the distance traveled along the road surface by the cutting
`machine 1 is continuously calculated by the controller 55
`based on the input from encoder 57. The computer controller
`55 adjusts the speed at which the piston 43a of the cylinder
`43 is raised and lowered in order to complete its prepro(cid:173)
`grammed cycle within the forward distance traveled. This
`rate of vertical motion directly corresponds to the forward
`speed of the machine. Thus, referring to FIG. 5, as the
`cutting drum 3 moves along the width "W" corresponding to
`the specified width of a depression, the hydraulic piston 43a
`is raised or lowered at a rate sufficient to obtain the required
`depression depth "d" into the road surface in accordance
`with a specified radius of curvature "R". It will be under(cid:173)
`stood that as cutting teeth 170 wear below a minimum
`dimension, they may no longer provide a required dimen(cid:173)
`sion depth "d" dictated by specification and require replace(cid:173)
`ment.
`
`[0049] Preprogrammed instructions pertaining to different
`cylinder stroke cycles relative to required depression sizing
`and equipment speed are stored and saved in the computer
`controller 55. This allows the operator to quickly and easily
`adjust the depth and width of the cuts according to specifi(cid:173)
`cations or as field conditions require. These instructions may
`be in the form of an algorithm.
`
`[0050] The hydraulic cylinder 43 is a type which contains
`conventional internal position sensors (not shown) which
`can provide electronic feedback to the computer controller
`55 that is indicative of the position of piston 43a. This allows
`the computer controller 55 to check the actual stroke dis(cid:173)
`tance of the cylinder 43 as it travels, and to inform the
`machine operator by, for example, a visual display 60, such
`as a series of lights, LED readout, or computer monitor as to
`whether or not the cylinder completed its programmed cycle
`
`Page 14 of 19
`
`

`

`US 2002/0192025 Al
`
`Dec. 19, 2002
`
`5
`
`in accordance with the computer controller 55 instructions.
`Thus, for example, if the power unit 59 is moving too fast
`such that the cut cannot be completed as required, the
`operator will be alerted.
`
`[0051] Referring now to FIGS. 1 through 4, the mobile
`power unit 59 pushes the entire cutting tool apparatus 61
`across the road surface. The cutting tool apparatus 61 is
`supported on a front end thereof by a solid steel roller 62
`which is affixed to a shaft 63 which is carried by two
`bearings 65 and 67. The bearings 65 and 67 are bolted to a
`roller housing assembly 69 which is firmly attached to the
`front of the cutter housing 5 by a series of bolts 71 and slots
`73 formed in the roller housing assembly 69.
`
`[0052] The entire cutting tool apparatus 61 via the housing
`5, is attached to a mast 75 of the power unit 59 by a slew type
`bearing 77 which pivots to allow the cutting apparatus 61 to
`swivel. The mast 75 is also attached to the power unit 59 by
`hydraulic cylinders 79 and 81 (two of each, only 1 shown)
`and control arms (not shown). The height of the rear of the
`cutting tool apparatus 61 is adjusted by adjusting the mast
`cylinders 79.