CA1316079C

CA1316079C - Soft concrete saw

Info

Publication number: CA1316079C
Application number: CA000616016A
Authority: CA
Inventors: Edward R. Chiuminatta; Alan Ray Chiuminatta
Original assignee: Individual
Current assignee: Husqvarna Construction Products North America Inc
Priority date: 1986-03-25
Filing date: 1991-03-07
Publication date: 1993-04-13
Anticipated expiration: 2007-03-25
Also published as: CA1307735C; AU611680B2; AU1516288A; US4769201B1; US4769201A; US4889675B1; US4889675A

Abstract

SOFT CONCRETE SAW
ABSTRACT
In order to cut soft concrete before it has completely hardened, or about 12 to 18 hours after finishing, a rotating cutting blade and its drive motor are mounted on wheeled support platform. The blade extends through a slot in the platform, and also through a skid plate depending from the platform, in order to cut the concrete below the skid plate. The slot and the skid plate are sized to support the concrete as it is being cut and to inhibit cracking and chipping of the concrete during cutting. The slot preferably has as little space as possible between the sides of the slot and the adjacent sides of the cutting blade. An extendable handle allows the device to be used beyond the physical reach of the operator.

Description

~ ~3~6079 SOFT CONCRETE SAW
Back~round of the Invention This inven~ion relates to concret~e~ ~hich is a combination of a hydraulic cementing sub~tance, aggregate, S water, ~nd, often other substances to impàrt specific properties to the concrete.
When concrete ~s poured it is typically in a watery or flowing state which allows the concrete to be ~pread evenly over floors. After a period of time, varying with the mixture of the concrete, the eemperature, and the moisture availability, ~he concrete ~ttains a workable plasticity which permi~s the curface of the concrete to be formed and to retain a finish. Typical finishing means include trowelLng, rubbing, or brushing. Applying the lS desired curface texture is called "finishing" the concrete, ~nd may involve repea~ed cteps to sequentially refine the ~urface finish.
After ~he concrete i~ finished, i~ i~ allowed ~o Rtand for a period of time during which the concrete cures to : 20 Qbtain i~8 well-known, rock-l~ke hardness. The curing or Be~tin~ ti~e depends on ~he moi6ture ~vailable, the temperature, ~nd the $pecific additives ~dded to the concrete to ~ffect the curing eime. A~ the concrete cures ~t undergoe~ thermal ~tresses cau6ing the concrete to expand and contract in various manners depending on the ~hape ~nd thickness of the ~oncrete, and the type of concrete~ These thermal stres6es can cause cracking. The fu}ly cured and hardened concrete also expands and contraces due to temperature changes with ~he result that 30 crackR form in the conGrete-It is common practice to provlde ~lots or grooves atpredetermined intervals in the concrete. I~ the grooves extend ~ll ehe way through ehe concrete, they can act as a~ expan~ion or contraction ~oint to help prevent cracking of ~he concret~. If the grooves are only on the surface of the concrete, then ehe grooves cause the cracks to ~`orm ~,:

~L3~07~

810ng the grooves 60 that they occur at regular intervals and are not vi~ible. The grooves, but not the c~acks, are visible.
One advantage to placing the grooves in the 60ft, 5 concrete is that a weakened plane is provided by the groove and that weakened plane is now installed before the concrete start6 to cure and 6hrink. The concrete slab will typically seek out the weakened plane ~o crack in, if the plane i~ pre~aturely there.
~oPresently, these grooves are provided by formin~, or grooving a slot in the concrete ~ith a grooving ~rowel, ~hile the concrete i6 still wet, ~ust after pouring. This grooving i done while the concrete i~ very wet, and before the concrete is sufficiently hard to support a 15 per60ns weight. Thus this grooving typically requires a 6upport ~tructure which would enable the person doing the groovin~ to reach the interiors of concrete slabs without placing ehe person'~ wei~ht on the concrete. When the : concrete slabs ~eco~e ~ufficiently large, this method of providing grooves proves impract~cal and expens~ve.
This egpe of grooving ~u~ be done when the concrete i~ suf~iciently ~et, otherwi~e ~he grooving trowel cannot shove entrained rocks out o~ the way without it disrupting the ~ur~ce fini~h on the concrete. E6sentially, the concrete must be grooved ~U6~ a~ter lt is has juse been poured, ~t which time the concrete is 80 wet that the concrete someti~es tend~ to ~ag back ~o&ether and close the ~roove, thu6 requiring repeated groovin~ to ~aintain a de~ired groove depth or ~hape.
: ~or very large sl~bs of ~o~crete, ~anually grooving ~he freshly poured concrete ~s lmpr~ctical or very inc~nvenien~ and expen~ive. For such l~rge ~labs, the concrete is typically allowed to harden or ~et. Grooves :~~re then cut in the ~urf~ce of the concrete by use of a ~5 hlgh-powered, rotating, abra~ive 5aw blade, often lubric~ted with water. The blade i8 typically Lade of ~3~6~79 diamond abrasive material and is provided with a liquidcoolant and lubricant to facilita~e cutting the hardened concrete .
Since these concrete cutting ma~hines tend to be heavy, the concrete mus~ ~e fairly hard in order ~o support the weigh~ of the machine and QperatOr. Further, ~f the concrete i6 not 6u~ficiently hard when cut, these machines produce an unacceptably rough cut with a chipped or cracked ~urface along the groove. ~owever, the harder 10 ehe concrete, the more dlfficult ie i6 to out.
It is pos ible eo u~e a hand held rotary sa~d as i s often u~ed in cutting lumber, but us~ng a blade designed ~o cut concrete. Such saw6 are lighter weight, but still require hard concrete ~o support the operator and to provide cut grooves with ~cceptable ~mooth edges.
On ~n extremelg hot and dry day, the concrete may be ~ufficiently hard to 6upport a per~on'~ weight and not leave a per~anent indentation, about ewelve hours after ~he concrete has been poured. ~ypically, the concrete is not ~alked upon or cut until at least ~e next dsy, or about eighteen hours after the concrete has been finished.
If the concreee ~8 cut by ~ conventional water ~: lubricated with water diamo~d-abr~sive~6aw, the earliest it can be cut ~ the next day ~fter fini hing (about 18 hours), and even then a unacceptable cut i~ typically produced as the edges of the concrete by the groove tend to chip, ~pall and crack.
One major problem with cuttin~ ~fter the concrete ~:: cures and hardens i~ ehat between the time of the ini~ial f~nieh and the time it becomes prac~ical for a conventional concrete ~aw ~o be used, the concrete slab w~ll have ~tarted ie's normal characteristic to Ghrink as i~ drie6, thus cau~ing contraction ~tress and invariably cr~cking before the 6awing of contraction ioint~ can be performed. This characteri6tic shrinking usually takes place so~ewhQre between the t1me the initial finish is ^4-co~pleted and before it becomes practical to put a conventional saw cutting machine on the s].ab. The result is cracking of the ~lab before saw cutting can be initiated.
Fur~her, cutting the hard concrete i5 a 610w process, which is ~lowed ~till further ~o ~erioaicc~lly replace the cutting blades as ~hey abrade away. Finally, these types of machines tend to be not only bulky, but al~o expensive and time con u~ing to operate and maintain. The noise of ~o the ~aw abrading the hardened concrete i8 also very loud and unplea~antO
There thus exis~s a need to provide an easier and faster ~pparatus and method for ~utting grooves in concrete before the concrete cracks.
Sum~ar of the Invention Y
An apparatus i8 provided for cutting a groove in ~oft concrete. The apparatus can cut the concrete any ti~e after the concrete is finished ~nd before the concrete attains its rock like hardness, ~nd preferably before the concrete hs~ shrunk ~uffieiently to cau6e racking along planes other ~han those planes defined by the cut groove~.
The æoft concrete saw has a base plate on which are moun~ed two ~he~ls and a ~kid plate, each of which cont~ct~ the concrete to provide ~ three point support on the concrete. A ~otor i& pivotally ~ounted on the base plate. The moeor drives 8 circular ~aw blade with an up cut rotation. The ~aw blade eictend~ through a s}ot in the platform, and a through a corresponding slot ~n the ~kid plate, in ~rder to project into and cut the eoncrete below : 30 the ~kid plate~
The dlmensions of the 810t ln the ~kid plate are selected to ~upport the ~oncrete immediately adjacent the ~aw blade 60 as to prevent cracking of the concrete as it i. CUt- ~he dimen~ion6 of the sloe in the plat~orm are 35 ~180 selected to inhibit excessive build~up of concrete on 1 3 ~

the pla~for~ ~s the 6aw blade CUtE; a groove in the conc ret e .
Thè motor is ~oveably ~ounted on the platfor~ 80 that the motor and saw ~lade can ri6e u~ when the saw blade 5 hits a rock entrained in ~he cont rete . A 6pring connected between a support on the base plate and the motor, resiliently urges the aw blade into the eoncrete and allows adiustment of the ~orce exerted by the ~aw blade on ~che concrete which i6 being cut. Thi6 spring controls the 10 ease with which the saw blade mo~es as the 6aw blade hits rock or other ob6truction ln the concrete and helps prevent concus5~0n cracks as the blade hit6 such rocks or obstructions in the concrete.
A handle iB pivotally attached to the base plate to shove the base plate and saw across a large ~lab of concrete without hindering the pivoting motion of the saw blade. Depending upon the size of the concrete 61abs which mu~t be cut, a varying number of handle extensions can be added to ~ove the 6aw across the conorete.
~: 2~If the saw i~ to be retracted ~f~er being extended ~cro~s a slab, then a ~olenoid can raise the saw blade out of the concrete. A second solenoid locks the handle in~o a rigid ~or~entati~on with re~pect to the ba~e plate.
Shoving downward on the handle then rotates the ba~e plate onto two wheel~ while aimultaneously raising the Rkid plate off of:the concre~e 80 as to allow the ~aw to be ~: pulled back across the concrete on two wheels with minimum : ~mpact on the fini~h of the concrete fro~ :the ~liding of ~he skid plate.
:30To help ~tart the saw on the edges of the concrete, an extra wheel can be added to the base plate, oppo~ite the saw blade, ln order ~o provlde a ~table support ~ the ~aw blade begins cutting into the edge of the concrete. This ; extra wheel c~n be ~ffset slightly ~bove the other wheels on the base plate so that once the normal wheels are on the concre~e, the extr~ wheel i8 rsised above the concrete ~ 3 ~ 9 and no longer contac~s the concrete. Thus, the ~kid plate ~nd ewo of the wheels provide a three point ~upport and minimize rocking of the ba~e plate.
There is thus provided a light weight eaw for cutting soft concrete without the neéd for extensive alignment or support apparatus. Further, ~ince the saw i6 cutting sof t concrete, the blade need not be replaced 86 often, nor need the saw be as complex and expensive as previous saws.
Description of the Drdwin~s The pre6ent invent~on will be better understood from the description of the preferred embodiment which is given below, taken in conjunction ~ith the drawings (like reference character~ or numbers refer to like parts throughout the descrip~on), and in which:
t5 FIG. 1 is a perspective view o~ the ~nvention being operated in the middle of a slab of concrete;
FIG. 2 is an elevated per~pective view of ~he front of ~he saw of this invention æhowing the motor and blade in a lowered position.
FIG~ 3 ~ ~ lower perspective view of the ~aw of this :invention, ~howing the motor ~nd blade in a raised : ~ : pos~ tion;
FIG. 4 is an elevated per~pective view of the back of the saw of this invention;
FIG. 5 ls a top elevational view of the ~aw of this lnvention;
FIG. :6 is a -side elevat~on of the ~aw of this inventlon in operation;
FIG. 7 i~ an elevational view of the 6aw blade and ~lot $n the skid pla~e;
FIG. 8 ie a per6pective view of an al~ernate e~bodiment of ~his invention;
~IG. 9 is a 6ectional vlew taken along A-A of FIG. 8, ~howin~ an alternaee embodiment of thifi invention.
FIG. 10 iæ a sectional view taken-along A-A of FlG. ~, ~howing an alternate embodi~ent o~ this invention; and ~ 3 1 ~

FIG. 11, i~ a sectional view taken along A-A of ~IG. 8 ~howing an slternate e~bodiment of this invention.
FIG~ 12, ~hows how the quality of the cut groove is affected by the ~pacing between ~he cuttin~ blade ~nd the S side~ of the aperture in the base plate.
De6cri~tion o~ the PreferrYd Embodiment As is ~hown in ~IG. 2, by way of illustration, and not by limitation, ~ ~oft concrete saw 10 co~prises a base plate 12 having a generally rectangular shape. The base plate 12 has ~ lower surface generally facing a slab of concrete 13, with an upper surface of the base pl~te faclng sway fro~ the concrete 13.
Along one of she longer side6 of the rectangular plate 12 there are atteched two front wheels 14 and 15, and a rear wheel l8. On the o~her long ~ide of the rectangular b~se plate t2, generally oppo~ite the r~ar wheel 18, it is located rear ~heel 20. The rear wheel 20 sets in a recess 22 (~IG~ 4) $n the base plate 12 such that the edge of the rear wheel 20 does not project beyond ~he edge of ~he 2~ generally~receangular ~ase pl~te 1~, ~6 described in more detall hereinafter.
A ~upport surface or plaee i6 in movable contact with t~e ~urface of ~he concre~e 13 in order to 6upport the surface of the c~ncrete im~ediately adjacent the groove ~eing cut in the concrete 13. In the illustrated embodiE~ent, this ~urface takes the form of a fikid plate 24 which depends from the base pl~te 12 in the direction of the concrete 13. The skid plate 24 is on the sa~e ~ide of the ba~e plate 12 ~s i~ ehe reoe~s 22 and the rear wheel 20, and i~ adjacent the longer edge of the ba6e plate 12. The ~kid plate 24 ~ opposi~e the ront ~heels 14 and 16.
In normal use, the 6aw 1~ i8 supported on the concrece 13 at three point6, the ~kid plate 24, the front wheel 14, ~nd the rear wheel 18. It i6 believed ehat the three , point6 o~ contac~ provide a more stable ~upport and cause ~3~7~

less wobble of ~aw 10 ~han would other support methods.
The wheels 16 and 20 are 6paced approxi~ately one-eighth to one-fo~srth vf an inch froTn the plane defined by the skid plate 24 and wheels 14 ~nd 18, ~o th~t the wheels 16 and 20 do not nor~ally contact the concrete 13 as ~he sof t concrete 6aw 10 i8 operated. The purpose of wheels 16 and 20 wi1 l be de~cribed later.
The wheels î4, 16, 18, and 2() can be the 6ame wheels as used on roller ~kates or sk2tebc~ards. The wheel~ are approximately 2.5 inches in dia~eter, and 2.5 inches wide. The ~heels are ~oun~ed to the base plate 12 80 as ~o rotate freely as the base plate 12 and saw 10 DDove along the concrete 13.
Referring to FlGS. 2 and 3, the skid plate 24 is a generally rectangular strip of metal having rounded ends 26 and 28 between which Ls a flat piece 30. The flat piece 30 is generally parallel to the ba e plate 12. The flat piece 30 coneact~ the concrete 13 in order ~o help upport the weight of the ~aw 10. The rounded ends 26 and : ~ 2a 28 preve~t gouging the surface of the soft concrece 13 as the aw 10 cuts the csncrete 13.
~ The area of the ~kid plate 24 in contac~ with the : concrete 13, and the area of the wheels 14 and 1~ which ~: al~o help ~upport the weight of the saw 10, are all sized to provide a large enough area to distribute the weight o~
the saw 10 wi~hout detr~mentally marking or 6ubstantially t~maging the 6urface finish on the soft concrete 13 which i s be ing cut .
Referring to FIGS. 2 and 4, on the upper surface of plate 12 iQ mounted a ~otor 32. The motor 32 drives a rotating cutting mean~ such as circular ~aw blade 34 (~`lG.
43 which in turn cut~ the concrete 13 (FIG~ 2) ~o ~orm a groovea Referring to FIG. 2, ~aw blade 34 is cypically circular and made of earborundum, or diamond coa~ed ~teel. The blade 34 has two generally flat 6ides, a 1316~79 g leading, or cutting edge, And a trailing edge. The 6aw blade 34 typically has little or no kerf, or tooth offset. Slots in the ~aw blade 34 carry the cut concrete out ot the concrete 13 to leave 8 groove or slot in the concrete. In the lllus~rated embodiment, à 4.25 inch d$a~e~er ~aw bl~de is used. Such blades are commercially available.
The Baw blade 34 rotates about an ax:Ls ~ub~tantially parallel to the ba~e plate lZ, ~nd substantially perpendicular eo the dlrection of tr~vel ~f the 6aw 10.
The ~aw blade 34 thus rotate6 in ~ pLane which is aub~tantially parallel to the longer edges of the rectangular base plate 12, ~nd 6ubsc~ntially parallel to the direction of tr~vel of the ~aw 10.
Referring to FIGS. 2 and 3, the ~aw blade 34 extends through an aperture auch as slot 36 (FI~. 2) in the base plate 12, ~nd al~o through an aperture ~uch a~ slot 38 (FIG. 3) in the skid plate 24, in order ~o cut the concreee 13 tFIGo 2). Thus the slot 36 i8 a generally rectangular slot locat~d substantially parallel to and : along :the length of ~he longer 6ides of the ba~e plate Spaced below, and in ~ub~tantial alignment with slot 36, i ~lot 38. The 810t 38 i~ al80 generally rectangular in hape, and i8 placed in the flat piece 30 of skid plate : 24. The width ~nd length of 6lots 36 and 38 are sufficiently large ~o that the-6aw blade 34 does not bind and size on the edges of tho~e~Ælot ~ Re~ferring to FIG. 2, the 6aw blade 34 rotates with an 3G up-cut mo~ion such that the rotation of the cutting edge of the saw blade 34 is out of the concrete 13 which is being cut, rather than being into the concrete 13.
AIternately phrased,:the rotation of the circular blade 34 is ~uch as to impede the orward motion of the saw 1~, rather helping puIl the saw 10 in the direction of travel.

~3~07~

This up-cut 6aw rotation i6 used to remove the soft concrete ~rom the groove cu~ by the 6aw blade 34. lf the saw blade 34 had a down CUt rotatlon, then the ~oft concrete cleared by the blade 34 could fill in ehe groove S lmmedi~tely behind ~he blade 34, effectively`fillin~ In the groove with ~oft concrete. The up-cut rotation removes the concrete 13 fro~ the cut groove and helps prevent ~he return of that removed concrete ~rom filling in and hardening in the 610t-This up-cut rotation of the blade 34 is eontrary to conventional wisdom and usage which essentially says thst the blade 34 should CUt into the 6urface on whieh the quality of the surface finish adiacent the cut ~roove i8 important. Since the ~urface finish i8 ~mportant only on t5 the visible ~urface of the concrete 13, conventional practice would require a down-cut rotation.
The reaAon for conventional practice ifi believed to be that the down-cut rotation relie~ on the mass of the . ooncrete, into ~hich the blade i6 cutting, to ~upport the concrete adjacent the blade and to provide an acceptable quality of cut. Concrete has much bet~er compressive cap~bility than tensile capability. The down-cut rot~ion keeps the concrete adjacent the groove in compre~sion, ; which ~inimizes chipping ~nd cracking. The up-cut 25 rotation place~: the concrete ~djacent the groove in tension, which with ~ conventional concrete cutting : device, would result in unaccep~able chipping and cracking of the concrete adjacent the 6urface of the cut groove.
: A 6afety 6hield 40 is connected to the ~otor 32 60 as ~: 30 to 6urround and shield the portion vf the cu~t1ng blade 34 ~: which do~6 not project through the 610t 36 in ~a~e plate : 12, The ~otor 32, shield 40, ~nd blade 34 thu~ form an integral unit in the illu6trated embodiment. In fact, it i8 believed po6sibl:e to use a c~mmereially available wood ~aw, so~etimes c~lled ~ circular hand 88W, as the basic motor 32 and ~hield 40 of thi6 lnvention. References to 1 1 ~ 31 ~ ~9 these part~ ~s an lntegral unit does no~ mean, however, that they could not be ~eparate componen~s performing the same function.
For reasons described laeer, it is desirable to hav~
~he blade 34 moveably mounted ~o that ehe blade 34 can yieldingly ~ove in re~ponse to contact with obstacles in the concrete 13. In che illu~trated emb3diment, ~s ~hown in ~IGS. 4 and 5, the motor 32, ~nd thus ~he blade 34, is pivotally ~ounted to ba~e plate 12 ~o a~ to rotate absut ~n axis ~hich is ~ubstantially parallel ~o the rotstional axis of blade 34 (FIG. 5). There i8 thus a pivot chaft 42 which, has ~ne end connected to ~o~or 32 vla a bracket 44, with ~he other end of the shaft 42 being connected to the ~hield 40. The plvot ~haft 42 i8 rotatably connected to the ba~e plate 12 by trunnions 46. The longitudinal axis of pivo~ shaft 42 is $~bseantially p~rallel ~o the rotaeional axi~ of ~otor 32 and i~ sub~tantially perpendicular to the direction in which the concrete 13 (FIG. 2) is to be cut, grooved, or 6lotted~
2~ In ~he lllustrated embodiment there is a ~eans for re~iliently urging the blade 34 ~gains~ the concrete 13 ~ith a predeterm~ned force. This resilient ~eans preferably take~ the form of re~ilien~ sprin~ ~ean~,: as foll~ws.
Referr~ng to FIGS. 2 and 5, attaehed to ehe ~hield 40 at the end of the shield which i~ opposite the connection with pivo~ chaft 42, is a projec~ion 48. Referring ~ow ~ to FIGS. 2 and 6~ projection 48 i~ on the e~terior of the : : ~hield 40, aw~y from the blade 34, and contains a notch or engaging aperture such aa ~perture 50~ A tension ~prlng 52 ha~ one end engaging or connected ~o the ~: ~perture 50, with the o~her end of spring 52 connected to pOse 54. The post 54 is connected t~ b~se plate 12 adjacent the motor 32, ~nd i6 8ub8t~ntislly perpendicular to the surface of the base plate 12.

-12- ~3~ 6~79 In the lllu6~rated emb~dimen~, ~he ~pring 52 6upports a portion of the weight o~ ~he Dotor 32, blade 34, and shield 40 so as to adju~t or regulate ~he a~ount of forc~
with which the blade 34 is forced again6t the concrete 13. Several factor~ can be varied to conerol the amount o~ force which the blade 34 exere~ on the concrete 13 during cutting. Such factor6 would include ~he dis~ance between the pivot ~haft 42 ~nd the motor 32, the di6tance between the pivot ~haft 42 and the spring 52, ~he type, ~ize, and method of mounting of the 6pring 52, and the weight of the motor 32.
In the illu6trated e~bodiment, a 7.5 ~mp, 11,000 r.p.m. motor 32 weighing about 6.2 pounds, i~ connected to a ~pring 5~ having a diameter of 3/8 of an inch, and an uncompres~e~ length of 1.75 inches. The ~pacing between the ~pring 52 nnd the pivot shaft 42 is approximately 7.5 inches. The distance between the center line of the motor 32 (and the rotstional axis of blade 34) and the p~vot shaft 42 iB ~pproximaeely 3.5 inches.
Re~erring to FIG. 6, the force exerted by ~pring 52, : and ~he re~ulting force exerted by blade 34 on the concrete 13, ~ffect6 ~he quality of ~he slot or groove which :ia cut in the concrete 13. The concrete 13 iB an : ~ggregate of rock, 6and, and cement, ~ith the rock being of variable size dependlng upon the requirements for the ~trength of the concrete 13. When the blade 34 hits a rock or o~her obstruction buried ln the concrete 13, problems can ar~e. The een ion on the spring 52 can be ad~usted to reduce these problems and to accommodate 3~ varying ~ize~ of a~gregate in the concrete 13.
If the ~otor 32 and blade 34 sre rigidly ~ounted to the ba~e plate 12, then the entire concrete B~W 1 0 can conceivably c~e to a ~ole~n~ halt until the blade 34 can cut through the entrained rock. Alternatively, if the 3~ concrete 13 is ~oft enough, the ~ock ~ay be slightly pu~hed out of the way which can cause surface damage, an 1~. 3 ~7 unacceptable ~aw cut, or residual cracking before ~he r~ck can be cut through. Still furth~r, the saw 10 could bounce up so as to disengage the blade 34 or the skid plate 34 ~rom contact with the concrete 13. In each o~
these cases, the 6udden halt ~r change i.n the ~otion of concrete saw 10 can ~ar the ~urface finiæh of the concrete t3. Perhaps more 1mportantly, the æudden impact of the ~lade 34 with the rock can jar the rock 6ufficientl~ to : caufie residual cracking of the concrete around the rock.
1~ Similar results can occur i~ the blade 34 i6 mounted 60 that ~ predetermined force c~n cause ~he blade to move separate from the base plate 12, but ~n exce~sive force is : exerted by ~he blade 34 on the concrete 13O The concrece can crack, ~ rough cut i~ made, snd the surface finish of t5 the concrete can be i~paired.
The goal of ehe spring 52 and the pivo~ing of the ~otor 32 and blade 34 is to allow adjustmen~ of ~he force between ~he blade 34 and the concrete 13, and to allow movement o~ ~he blade 34, ~o that the contact be~ween the blade 34 and ~n entrained obctacle~ ~uch a~ a rock, does not damage ehe ~urface of the concrete 13 or cause re~dual cracking of the concrete 13.
For the lllu6trated embodiment, the weight or force ~exerted by ~he ~otor 32, shield 40 an blade 34 is a~o~t ; 25 5.5 pounds, which i8 greater than desired. In ~he illu6~rated embodiment the ~pring 52 offloads a portion of the weight 80 that only about 2.5 - 3O0 pounds of force are exer:ted by the blade 34 sn the concrete 13. Thus the blade 334 is re6iliently urged into contact ~ith the ~oncre~e with ~ force of about 3.0 pounds. If needed, the exten~ion gpring 52 could be readjuæted or replaced with an appropriately si~ed sprin~ in order to provide the desired predetermined force :between the blade 34 ~nd ~he concrete 13.
~: 35 One re~ult of adju6ting the force be~ween the blade 34 and the concrete 13 i~ that the deptb o~ the groove cut by ~3~6079 the blade 34 can vary depending on how fast the ~aw 10 is moved. ~urther, the depth of the ~r~ove may be less when the blade 34 hits rocks entraine~ in the concrete 13. For example, it i~ believed preferable for the depth o~ th~
grooves cut by ~aw 10 to be about 0.5 inche6 deep, with a minimu~ depth of .125 inches being marginally acceptable. As the force o~ the ~pring .52 offloads more and more of the ~orce exerted by blade 34, the blade 34 will cut a shallower and ~hall~wer groove for a constant 1~ eravel of 6aw 10. If a fu~l depth cut groove i~ required, the ~2W 10 must move slower as the forre between the blade 34 and the concrete 13 increases w~th ehe depth of the groove. If the ~aw 10 i~ moving fast enough, ehen when the blade 34 hi~6 an entrained rock, th~ blade 34 bounces up, only partially cutting the rock, and cutting a shallower groove at that point.
Alternately phrased, the greater the tension applied to the spring 52, the les~ the weight or force applied to the ~aw blade 34, which in turn provides a faster forward cut but also a 6hallower cut. The less the ~ension ~pplled to ehe spring 52, the ~reater ~he weight applied to the ~aw blade 34 which in turn deepens the overall groove depth and ~lows the forward ~ravel, If too much : weigh~ i~ applied to the blade 34, ~he ~kid plate 2:4 will rise off of the 6urface of concrete 13 and the groove quality will become unacceptable.
The exact mechani~m by which the offloaded ~nd pivoted blade 34 optimally cut~ through entrained rocks is uncertain. lt i believed e~at ~ correct aelection of the force exerted by the blade 34 on the concrete 13 will allow the blade 34 to ri~e up over an entr~ined rock so ~0 ~B ~0 circumvent the rockO It i~ believed that rising : up to the rock allows the blade 34 to cut down into the rock and doe~ not c~use a 6evere ~olr to either the entrained rock or th~ concrete Baw 10 . This force selection ~u6t con~ider the individual concret~ mix ~31~7~

design, snd especially the size of the aggre~ate (rock) in the concrete. Alternately phresed, it iB believed that if the force with which the blade 34 is urged into the concrete 13 ls too great, then the operator must shove the S ~aw 10 in order to cut ~ideways through the rock. The resu}t is residual crackin~ around the rock, either from the lnieial i~pact of the 68W 1 0 with ~he entrained rock, or fro~ the sideways force of the oper~tor cutting sideways through the rock.
1~ It ~F belleved that if the force i8 correctly adju~ted, the blade 34 can resiliently accommodate ~he ~mpact with ehe e~trained rock to ~inimize or prevent damage to the concrete finish. A trade off between the desired depth of the cut ~roove, and the permiss~ble variations in ~hat depth ot the cut groove exist6~ The illus~rated embodiment is one combination that has been judged preferable when working with aggregate up to one ( 1) ~nch in ~ize.
Thi6 proble~ with obstructions, such as entrained rocks, i~ not encountered with conventional cutting machines ~1nce the concrete 13 ~ ~ufficiently hardened, and the progres6 of the ~aw sufficiently ~low, ~o ehat the en~rained rocks are cut without the re idual cracking : concern. ~or the grooving trowel6, the entrained rocks are no problem since the concrete ~ grooved just af~er pouring, while the rocks can be slo~ly urged out of the way of the groovln~, trowel without causing cracking.
While the smount of force beeween tbe blade 34 and che concrete 13 may vary æomewhat depending upon the size of 30 the blade 34 and the ~ize of the rocks entrained in the concrete 13, it i6 believed that this force should be about 2.5 - 3.0 pDunds for the illustrated embodiment.
This ~orce ha~ been found: ~uitable for cutting a 1/2 inch deep groovt in a 4 inch thick ~lab of concrete 13, with 35 rock or aggregate up to 1 lnch in 6i~e.

13~7~

The quality of the ~roove cut in the concrete 13 is also affected by the si~e of the 6l0t 38 (FIG. 3) with re6pect to the por~ion of the blade 34 extending throu~h that ~loe. The force exerted on the concrete 13 by the skid plate 24 helps to 6upport the ~urfacle of the concrete 13 immediately adjacent ~he gro~ve which is being cut in the concrete 13. If the ~pacing between the sides of the blade 34 and the ~lot 38 is too great, then the edges of the cut groove will become rough ~nd uneven. It i6 also poæsible that spallin~, chipping, or ~ur~ace cracking immediately adjacen~ the edges of the groove will occur.
It i6 preferred ~o h~ve the skid plate 24 support the concrete 13 immediately adjacent the groove being cut by blade 34~
~eferring to ~IG. 7, it i8 preferred ehat the spacing b and c between the side6 of the blade 34 and the sides of the slot 38 in the skid plate 24 be controlled.
Testing indicates thRt a spacing as close ~s possible to : zero, without blnding, provides the best surface finish 2~ ~djacent ~he cut ~roove. A ~pacLng of l~ss than 1/16 inch (0.0625 inch) produces a cu~ groove of accept~ble quality with no readily perceived crscke or chips or ~agged edges a ~pacing of 1/16 inch or slightly greater, of b and c, provides a Burface fini~h ~djacent ~he groove that is 3udged to be of questionable acceptability, hsving chips and crsck~ that are not perceptible at a distance, but notieeable close up. A cpacing of 3/32 of an inch : provides ~ groove that i8 U ually unacceptable in terms of chipping ~nd cracking, ~nd overall finish. A æpacing of over 3/16 of an inch pr~vides a groove deemed unacceptable ~n terms of cracking, ~palling, or cos~e~ic app~arance at the edge of the groove.
~ he~e re6ults are derived from ~eæt dsta which indicaees ~hat the relation~hip between ehe slot spacin~
35 : and the quality of cut ~ not linear. ~IG. 12 below, illu~trates the test dsta and ~hows the manner i~ which L3~7~

the spacing ls believed to affect the quallty of the surtace finish o~ the concrete 13 ~djacent the cut groove.
It iB believed that the effect of ~he spacing b and c on each Ride of ehe 6aw blade 34 is independen~ of the quality of the cut or groove formed on the other slde of the blade 34. Thu~, lt i~ possible ~o have the 6urface finish on one side of the groove acceptable, with the opposite side ~f the groove producing an unacceptable finish adjacent ~he cut groove because of too w~de a 1 Q 8pacing, It iB believed pos6ible tha~ the spacing may be critical only at the cutting edge of the blade 34 since that locstion i6 where the concrete 13 i6 being re~oved by the up-cutting m~tion oi the blade 34, and the only plsce lS where ~he concrete 13 is being theoretically placed in ~ension by the blade 34 60 ~6 to cause cr~cking and ch$pping. In practice, however, the ~aw 10 may wigKle and obble 8C) that the blade 34 actually contact~ the concret~
13 ~t point6 other than the cutti~g edge of ~he blade 34. Thu~ the $10t 38 preferably has side~ which correspond to the ~hape of the side~ of the blade 34, and ~re ~pared ~ clo~ely as po~sible to the blade 34 ~dithout bindtng ehe rotation of the blade 34.
Referring to FIGS. 3 ~nd 7, the s~acing between the 25 up-`cutting or outting edge o~ ~he rotating bl~de 34 and the adjacent end of the slot 38 is al30 concrolled in the illu~tra~ed embodiment~. If the front edge of the slot 38 extends into t~e rounded end 26 of the ~kid plate 24, then plaeing the cuttlng edge of the blade 34 ~dj acen~ this end 30 of the 810t 38 can cause ~ ~ulld up of ehe cut concrete which can Bqueeze ou~ of the 610t 38 and under the rounded :: end 26 80 ~ to mar the ~urface fini~h of the concrete ~3 or cau~e tYlting of the saw 10.
It is preferred ehat the front or leadin8, ed~,e of the 35 6lot 38 which is ~djacent the leading or cutting, edge of the blade 34 not extend into the rounded end 26, but ~3~7~

rather terminate~ in the flat piece 30. ~urther, it is preferred that the space d between the cutting edge of the blade 34 and the Adjacent end of slot 38 be llmlted 60 as not to ~reatly exceed 1/4 of an insh. Ideally, there is S zero ~pacing between the cutting edge of ~l~de 34 and the end o~ the 610t 38. However, as the blade 34 wears, a ~pace will n~turally develop, and a maximum ~paced of ~bout 1/4 inch i6 preferred.
~he ~pacing between the back or ~railing edge of the blade 34 and the end of the ~lot 38 al80 affects the quality of the cut groove. It 16 pre~erred that the slot 38 be extended into ehe ~ounded end 28, or ~lternately that a tunnel or other open piece be provided. The pre~ence of a flat piece of metal on the concrete 13, ~mediately following the groove cut by the blade 34, ~ould act a~ a ~rowel ~erving to clo~e over or o~herwise : co~pro~i~e the quality of ~he groove which had previously been made. ~xtending the 610t 38 all the way eo the rounded end 2~ prevents closure of the previously CUt groove and al~o provides a ~turdy ~ttachment for the ~kid pla~e 24 ~h$ch prevent~ undue vibration during operation of the concrete saw 10 (FIG. 3).
~ Referrlng to FIG. 2, this desire eo prevent closing of ; the groove ~mediately after it ha6 been cut, al80 ~ffects the placement of the rear wheel 20. The outer edge of ~heel 20 i6 preferably placed close to ~he rotational plane of the bIade 34 and the ~roove cut by that blade, ~ but not ao clo~e th~t the wheel 20 would cause clo6ure of :: the groove cu~ ln ~he concrete 13 by the blade 34.
The size of the 810t 36 ~ith re6pect to the blade 34 16 also controlled in vrder to help prevent the freshly : cut concrete fro~ accu~ulating on the bl~de 34 and to prevent the fre3hly cut concrete ~rom being returned to the gro~ve which had ju3t been eut. Thusl ~he width o~
the ~lot 36 $~ preferably as close t~ the w$dth of the blade 34 as pos~ible. Limitatlons on the length of the ~L316~79 610t 38 must also con~ider ~ccommodating ~o~ion of che blade 34 as it pivots around the ~haft 42 (~IG. 4) when the blade 34 fitrikes rocks which are entralned in the concre~e 13.
As the concrete 13 is removed from the groove by the ~l~t6 in the blade 34, the concrete dislodges from the blade 34 ~nd is deposi~ed between the lower surface of ~he plate 12 faclng the concrete 13, and the interior sur~ace of the skid plate 24 which face6 the plate 12. About ~0%
of the eoncrete removed by the blade 34 is deposited on the lnterior of skid plate 24. As ~ore and more concrete di~lodges and accumulates, the concrete i~ urge~ off of the ~kid plaee 24 onto the adjoining ~urface of concrete 13. By the ~ime the dislodged concrete exits the skid plate 24, 1~ has hardened ~ufficiently 80 that it iS non-adhesive and ~oes not readily adhere or mold it~elf to the concrete 13. The heat from the cutting action of blade 34 ~ay contribute to this hardening.
It i~ not believed that the rotational ~peed of the blade 34 has ~ny siBn1ficant ~ffect on the Rpaclng between the blade 34 and the ~lot 3B. The ro~ational ~pe~d of the blade 34 doe6 hav~ æome ~ffect the speed and ease with ~hich the concre~e ~aw 10 can cut acro6s the ~urface of the concrete 13. Generally, a h~gher rotat1onal 6peed of the blade 34 ~llows faseer cutt~ng ~nd thus faster ~ovement of the concrete 6aw 10.
: Referring to FIG. 3, ~he width of the skid plate 24 is ' such tha~ it ~ot:only ~upports~a portion of the weigh~ of the saw 10, but ~lso allows hardening of the concrete after it h~s been removed from the groove cut by the bl~de 34. A ~ini~um w~dth of 0,5 inche6 has b~en found sufficient to allow the dislodged concrete to harden ~ndlor air dry before it ~lides off of the 3kid plate 24 onto the ~djolning concrete 13 (~IG. 2), yet ~u~ficiently large to prevent the side~ of the skid plste 24 from alicing llke wire, or ~inkin8~ rather than providing a 1316~79 support surface with minimal marring on the ~urface of the concrete 13.
Referring tO FIGSo 2 and 4, ehere i8 a h~ndle 55 attached to the ~otor 32. ~he handle 55 can be grabbed by a person in order to carry the concrete ~aw tO.
Referring to ~IG. 1, in order to enable operation of the ~aw 10 on large ælabs of concrete 13, without the use of ~caffolding ~o support the weight of the operator, extendable handles 58 can be att~ched to the ba6e plaee 1O 120 The ~xtendable handle~ 58 function like extendable broo~ h2ndles eo enable the saw 10 to be pushed out onto, and withdrawn from, a large ~lab of concrete 13. In short, the h~ndle 48 provides a IDeans of moving or propelling the saw 10 to cut grooves in ehe concrete 13.
~5 A ~ore detailed description follows.
Referring to FIG. 2, the concrete saw 1Q preferably has three points of ~upport at All times the blade 34 is cut~ng the concrete 13. The6e three points typically cor~prise ehe skid plate 34, ~nd two of the wheels 14, 16, 20 18, or 20, a~ described hereinafter. When the concrete ~aw 10 is first started on ehe ed~e of ~ concrete ælab, the three point~ of con~act compri6e the skid plate 24 and the front wheels 14 and 16. The wheels 14 and 16 are æpproximately equal distance from, but on opposite si~es 25 Of ~ the rotational axis of the blade 34r Thus, there is a ~table ehree point ~upport among the wheel6 14 and 16 and ehe skid plaee ~4.
The front ~heel 1~ is located approximately 1/8 ~o 1/4 of an inch further away from the concrete 13 than is the 30 front ~heel 14. Thu~, when the ~aw 10 h~s cut ~ufficiently far out lnto ehe concrete 13 so that the rear wheel 18 rides onto ehe 6urface of the concrete 13, the wheel 16 is lifted out of contact with the concrete 13, and the three point support then comprises the 6kid plate 24, the front wheel 14~ and the rear wheel 1~O The o~fset wheel 16 ehus ~erves as ~ gulde and support for the 13~ ~79 concrete 6aw 10 as the 68W 10 begins eutting into the edge of ~ concrece sl~b, but not ehereafter~
The use of an offse~ wheel 16 during ehe initial portion of ~he cut made by the ~aw 10 do~s cause the blade 34 ~o cut at an angle wlth respect to ~he ~urface of the concrete 13, rather than cu~ting perpendicular to the concrete 13. The smaller the offset of the wheel 16 wi~h respec~ to the other wheels, the less ~hi6 ~ngle will be.
During thi~ initial cut on ehe edge of the conerete ~lab, the saw 10 could be operated by ~he handle 56 attached to the motor 32. After the 6aw 10 i~ extended to the edge of ~he operator 1 6 physical reach, the saw 10 can be opersted by an extendable handle 58.
Referring to FIGS. 2 ~nd 6, the handle SB is pivotally connected to the base plate 12 at pivot block 60. The pivot block 60 allows the extendab}e handle 58 to pivot about an axis ~ubstantially parallel to the rotational axis of blade 34. As the concrete saw 10 moves oneo ~he concre~e 13 and further ~way from the opera~or, ~dditional extensions can be attached to the extendable h~ndle 58 at ~oints 59 (FIG. 1) in order ~o ~ccommodate the necessary reach. The connection of extendable handles 58 at joints 59 an be by diverse means such a~ ~crew ~hreads or bayonet ~oun~s which are well known $n the art ~nd not described $n detail herein.
:The connection of the handle 58 to the base plate 12 provides a meanfi for propelling the 6aw 1~ without rest~icting the movement ar pivot ~etion of the blade 34 ~bout: the pivot ~Xi8 42. The u6e of ehe handle 56 30~ att~ched directly to the motor 32 restric~s pivoting of the blade 34, ~nd can cause ~n~dvertent damage to the ~: finish of ehe concrete surface when the blade 34 hits a rock entrained ln the concrete a~ previously de6cribed.
: During operat~on of the ~aw 10, ehe greatest drs~
o~curs ~t the blade 34 and skid plate 24. The pivot block 60 is preferably placed adjacent the blade 34 80 as to - 22 - -~ 3 ~ ~ 079 move the concrete saw 10 withou ~kewing the blade 34 and saw 10. If the blade 34 skews ~o that the blade 34 is not parallel to the line of travel of saw 10, then not only is the resulting groove in the concrete 13 wider than normal, but the skewing of blade 34 can cause immediate or residual cracking, spalling, or chipping in the surface of the concrete 13 immediately adjacent the ~roove. Thus, it is d~sirable to have the force pushing the concrete saw 10 applied ~o as to cause as }ittle skewing of the blade 34 as possible.
Referring to FIG. 5, for the illustrated e~bocliment, applicant has found that the center line of the extendable handle 58 can be along a line substantially parallel to the cutting blade 34, and spaced approximately 1.5 inches therefrom, toward the mokor 32.
Referring again to FIGS. 2 and 6, the concrete saw 10 has completed its cut, it may be desirable to retract the concrete saw 10, rather than retrieve the saw 10 from the other side of the slab of concrete. As described be}ow, mechanisms are provided to retract the blade 34 from the concrete 13, and to pivot the concrete saw 10 so as to disengage the skid plate 24 from sliding contact with the surface of the concrete 13.
The pivot ~lock 60 is ~paced apart from the base plate 12 by a boss 62 so that the pivot block 60 is above the surface of the base plate 12. On the boss 62 is mounted a selector brack~t 64 which comprises a piece ~f metal roughly resembling a sector gear in shape. The selector bracket 64 has a narrow edge extending in the direction of the extendable handle 58.
Into this edge are cut recesses or notche~ 66~ These notches 66 are shaped and located so that they can mate with a tip 68 o~ a plunger 70 of a solenoid 72. The solenold 72 is mounted on, and is subs~antially parallel to, the extendable handle 58.
In operation, ~he angle between the extendable handle 5 and the base plate 12 will vary depending upon the ~' .

~3~L~Q7~

length of the handle 5~ and the distance of the ~aw 10 fro~ the operator. The ~ngle ia greater a~ the 6~w 1 comes nearer to the operator.
A remotely actua~able means is provided to allow removal of the Raw 10 ~rom ~ slab o~ c:oncrète without dragging the 6kld plate 34 on the ~urface of the concrete 13. When it i5 desired to retract the Baw 1 O from the middle of a slab of concrete 13, the ~olenoid 72 is energi~ed ~o that the plunger 70 extends to cau~e tip 68 to engage with an adjacent notch 66. Depending upon the angle of the extended hendle 58, ~he tip 68 will engage differing Dotches 66. ~he engagement of the tip 68 with the notch 66 provides a linkage connection whereby the handle 58 may be ~hoved down towards the ground to exert a t 5 torque or moment onto the base plate 12. In eB8ence ~ the : notches 66 and plunger 70 serve to lock the handle 58 into ; a fixed po~ition with re~pect to ehe ~aw 10. The result ~ is that the ~aw 10 tilts onto the~two rear wheels 1~ and ; 20 as the handle 5B i~ pushed toward the ground, thus enabling the 6aw 10 to be rolled ~f of ehe concrete 13 ~lab ~ithout the skid plate 24 dr~gging on the concrete ~3.
~; ~ As seen from Fig. 6, the rear wheel 20 i8 also located approximately 1 f 8 to l /4 of an inch further away ~rom the concrete 13 than i8 the rear wheel 18 or the front wheel 14, 80 thst the wheel 2û doe~ not normally contact the ~urface o~ the concrete 130 The off~etting of the wheel 20 cau~e6~a tilt to the ba6e plate 12 when ehe ~aw 10 is pivoeed ~o that it ~an roll on the wheels 18 and ~0. The ba e plate 12 ~u~t not overhang the offset wheel 2() so that the offset of the wheel 20 causes a corner of ~che ba~e plfite 12 to dig into ehe concrete 13 ~hen the base plate 12 ia tllted onto the rear wheel~ 18 and 200 To provide as wide a suppor~c as po~Rible in order to help ~` 35 ~inimize thiG tilting, the rear wheel 20 iLB preferably placed as close to the plane of the saw blade 34 as :13~6079 -2~-possible, withou~ causing che groove cut by the blade 34 to clos~.
Conceivably, the wheel 20 could be pl2ced on the opposite ~ide of the groove than the other wheels~ It is also believed pos~ible ehat the three point~ of support for normal operatlon could comprise the ~wo rear wheels 18 and 20 and the 8kld plate 24, ~ith the ewo offset wheels ~eing the ~ront wheels ~4 and 16. In his ca~e, the tileing of the ba6e plate 12 would not occur during go retrieval of ~he saw 1~ since there would be no o~f~et between the rear wheel3 18 and 20, with both of those wheel~ being on ~ubstan~ially csplanar axi~, if not the 6ame axis.
Another remotely actuatable means is also provided to di~en8~ge the blade 34 from contact with the concrete 13. Referring to FIGS. 2 and 3, a second ~olenoid 74 can be used to pivot the blade 34 out of contact with the concrete 13 (FIG. 2) before ~he retraction of the ~aw 10, or at any tlme desired. Thi~ ~econd solenoid 74 is preferably locsted adjacent the spring 52 80 as to provide a force between the baGe plate 12 and the ~hield 4~ which cau~e~ the blate 34 to p~vot out of lt~ normal position ~hich i~ in coneact wi~h the concrete 13.
More ~pecifically, there is 8hown the 60lenoid 74 connected to the motor 32. The solenoid 74 has a plunger 76 extending downward towardx the ba8e plate 12. When the : ~oleno~d 74 is energi2ed, the plunger 76 extends to contact and pu~h against the base plate 12 with the result that ehe shield 40t motor 32i and:8aw blade 34 pivot about the 8haft 42 ~o ~s to rot~te the blade 34 a predetermined d~tance, preferably out of corltact with the concrete 13. Pleferably, ~he ~olenoid 74 l8 connected adj~cent the blade 34, perhaps att~ched to the shield 40, 80 a~ to place the force exerted by the ~olenoid 74 adjacent the :~ 35 greatest res~tance to disengaging ~he blade 34 from the concrete ~3~

` 11 3~079 Referring to ~IG. 2, solenoids 72 and 74, snd the motor 32 are connected ~o electrical wires 76 ~hich run along extendable handle 58 to a con~rol device-78 on the end of the handle 58 where they are controlled by the operator. Thu~ the ~olenolds 72 ~nd 74 and the motor 3 can be remo~ely ~ctuated by the operator of the ~aw 10.
If the wires 76 are not sufficien~ly long, then connectors known in the art and no~ described in detail herein, allow the use of exten~ion6 to the wires 76 as ~ore and more handle6 58 are added.
A ~ounting bracket 80 is plvotally connected to ~he pivot shaf~ 6.2. The mounting bracket 80 is ~hown as connectlng to the pivot shaft 42 ~t two locations on generally opposite ~ide6 of the ba6e plate 12, in order to provide a ~able connection to the saw 10 . Connected to the mounting bracket 80 i5 a tubular cylinder ~2 which is located 30 tha~ extends along a line parallel to the orientaeion of the saw blade:34. One end of the handle S8 extend6 through the cylindrical tube 82 ~uch that the : 20 ha~dle 58 can rotate within the tube 82. An end of the handle 58 pro~ec~s beyond the tube 82. VariouR devices, such as ~nap ring~ 84, allow the handle 58 t4 rotate ~ithin the cylindrical tube 82, but restrain motion of the handle 58 along the longitudinal axi6 of the handle 58 and cylindric~l tube 82.
Thus, the handle 58 can guide and propel the 6aw 10 tbrough the connection with the bracket 80 and pivot shaft 429 ~he pivotal eonnection between the bracket 80 and the pivot ~haft 42 allows the handle 58 to move up and down in 30 a vertically orientation with re~pect to the concrete 13.
In ehi~ alternate e~bodiment, a tl-shaped br~cket 88 has one 6ide connected top, and preferably lntegrally formed with &afety ehield 40. The open ends o~ ~he U-~haped bracket 88 ~re al~o pivotally connec~ed to the 35 pivot ~haft 42 6uch that the bracket 88, 6af ety 6hield 40, motor 32, and saw blade 34 are all connected so as to ~L311 6079 pivot about pivot ~haft 42. Thus, the U-~haped bracket ~8, and the mounting bracket 80. both pivot about th~
common ~haft, pivot 6haft 42.
A flexible member such as wire cord 90 ha~ a first end S connected to the U-shaped bracket 88, and a ~econd end connec~ed to that por~ion of the h~ndle 58 extending through the cylindrical tube ~2. As the handle 5~ is rotated in ~he cube 82, ~he cord 90 wrap~ around the end of the handle 58 &0 that the length of the cord 90 is 6hortened. Shortening ehe l~ngth of cord 90 pulls on ~he bracket 88 and pivots the ~aw blade 34 abou~ ~he ~ivot shaf~ 42 so tha~ the ~a~ blade 34 can be ~ithdrawn fro~
contact with the concrete 13, as ~llu~trated in FXG.
10?. Controlled ~hortening of the cord 90 can also be used to vary the depth of the groove cut ~n the concrete 13 by the 6aw blade 34.
The motor 32 i8 also connected to the base plate 12 by ~ean~ of a ~econd flexible me~ber ~uch a~ the 6econd wire cord 92. Preferable, the second cord 92 has a firs~ end 2~ connected to the front of ~he base plate 12, on ~he sRme end as the wheel 14 is located. The second end of the ~econd cord 92 i~ preferable connected to a projecting bracket 94 which from, and is connected to, the motor 32 as shown in FIG. 8.
The 6econd cord 92 i8 normally ~lsck when the aw blade 34 i~ at its desired cutting depth in the concrete 13, as illufitrated in FIG. 9. Preferable, ~he ~econd cord 92 i8 al~o ~lack when the fir8t cord 90 ~8 ~hortened 60 as to c~u~e the 6aw blade 34 to p~vo~ out of contact with the 3~ concre~e 13, a~ illustrated in ~IG~ 10 O ~urther pivoting of the ~aw blade 34 ~nd co~nected ~otor 32, causes ~he second cvrd 92 to ~ecome taut and exert ~ force on the front of the base pla~e 12.~ he force exerted by the ~eco~d cord 92 i6 6ufficient, the saw 1~ ~ill pivot on 35 the rear wheels 18 and 20 (FIG. 7), ~o that the 6~id plate 24 i6 moved out of contact with the ~urface of the ~' ' ~3~079 concrete 13, as shown in FIG. 11.
Thus, the handle 58 c&n be used to not only propel and guide the Baw 10 , but also ~o disengage the ~aw blade 34 from the concrete 13, and further to di~engage the 6kid S plate 24 from contact with the 6urface of the concrete 13, ~o ehat ~he ~aw 10 can be withdrawn fro~ the ~urface of the concrete t3 with mini~um danger of damaging the : ~urface of the concrete 13 by inadvertent 6craping of the skid plate 24.
10The s~w 10 in preferahly u~ed to cut soft concrete, not hardened concrete. The 6aw 10 can be used just ~fter the concrete 13 has been finished. A~ the time of ~ini6hing, the concrete 13 hes attained a workable plasticity that allows the concrete 13 to be worked and retain a surface ~inish, but the concrete 13 is not ~ufficiently hard to allow acceptable cutting ~y conventional saws or methods. The saw 10 can also eut concrete 13 ~hich has ~et for sever~l hours, and is believed to work with any conerete that i~ too soft, or not ~ufficiently hard, to be cut ~atisfactorily by conven~ivnal abrasive cutting mach~Des.
As prevlou6ly ~ent~oned, such conventionAl cutting machines can produce cuts of unacceptable or dubious accep ability from as li~tle as 12 hours after finishing if the day is extremely ho~, ~ay over 100 degrees fahrenheit. These conven~ional cu~ting ~achine~ typically are ~ot ~sed until the next day, (about 18 hours lseer) and even then typically produce unaccept~ble cuts. The 6aw 10 w~ll eypically be used be~ore the~e 12 hour and 18 hour figures. The 8~W 10 ~llows "~ame day" cutting of grooves with sceeptable ~urface finishes ~d~acent the cut 3rooves. It i8 belleved that the ~aw 10 could be used at or beyond the 12 and 18 hour figure~ and produce a cut :groove having a superior ~inish ad~acent the surface of the groove when compAred to the ~roove q~ality of conventionAl abra~ive ~achines~ Ho~ever, the wear on the ~' ~316~79 blade 34 would be greater than normal.
Ideally, ~he 6aw 10 would be us~d to cut grooves in the eoncrete 13 before the concre~e 13 has incurred its characteristic 6hrink ~hat occurs during æettin&, to an extent that eracks begin forming in the concrete 13.
More ~pecifically, ~he finishing of concrete typically proceeds through several ~ages. The fir~t stage i~ to pour the concrete, ~amp it and 'rbull float" the surface ~o level ehe 6urace. At this ~tage, the concrete is wet, and cannot be ~?lked upon without 6inking into ~he concrete.
If the concrete i8 grooved with an edger or grooving trowl, i~ i~ first done at ~hi~ stage, but muse be repeated later. The concrete i8 ~ypically not left with this coarRe of a finish, although such a rough finish may be adequate for road surfaces and such.
At this first stage the concrete has a hardness of which can not be measured by the conventional Swiss Hammer testR u6ed for concrete. The Swiss Ham~er relies on the rebound of a ~haft from the hardened surface of the concrete ~o ~easure hardness in pounds per ~quare inch, or p8io At this bull float stage, the concrete $6 80 soft that the plunger on the SWi8S ~ammer sinks ~nto the : concrete and rebounds.
The~saw 10 ~s believed to be able to cut the concrete at thi~ bull float ~age and form an acceptable groove, although the weight of the caw 10 will cause the 6kid plate 24 and wheel~ 14-20 to leave indentations ~n the surface of the wet concrete 13. If cut et thls ~age, the eoncrete 13 iR preferabIy a~ wed to have itB 6urface air 3~ dry ~o that the indentation6 fro~ the wei~ht of the saw 10 are mini~al or Don-existeDt.
The ~econd~ ~tage of fini~hing is called the "fresno"
~tage. Here the concrete has hardened, but ~till cannot ~:. be ~alked on without ~inking into the concrete, The fini~hing during this ~t~ge i~ done by long handled tools slnce the concrete will not support a person's weight.

~3~07~

The ~equential working of the concre~e ~urface with tools repea~edly brings ~oisture ~nd cement ~o the surface and allows a smoother finiih to be applied to the concrete 13. If grooves are formed in the concrete by use o~ a grooving ~rowl, the grooves must be r~egrooved at this ~tage, and after each successive f inishinl~ ~tep.
The concrete during thi6 fresno ~tage is 6till too soft to obtain an accurate hammer hardne6s. The ~urface of the concrete 13 iB s~oother than that of the firs~
tage. The ~aw 10 will cut $atisfactory grooves in the surface of concrete 13 finlshed to this ~tage.
~refera~ly, the surface of the concrete 13 will be allowed to ~ir dry ~o s to mini~ize the marks formed in the surface of the concrete 13 by the weight of the 6aw l0o Conventional concrete saws will not work sati~factorily at this fresno 8tage of ~inishing. The grooves will be ~agged at the edges. The concrete will be ~till be waQhed away by the water lubricant of the abr~sive cutting machlnes. Fur~her, the we~ght of conventional cutting machines will leave unacceptable indentatlons ln the 6urface of the concrete.
: m e third ~age of finiehing ~se6 power trowl~ or fini~hing machines to repeatedly ~mooth the 6urface of the concrete 13. At this st~ge the concrete 13 i~ hard enough 30 a per60n will not sink in deeply, but the ~urface of ehe concrete 13 will form indentations from the per~on's weight. The operator of the finish$ng ~achines iu6t walks BO thae the machine a~ooth~ out the indentations. This machine flni8hing i8 done ~everal time~, with the ooncrete ~urf~ce being allowed to: air dry between each finishing :~ operatlon. With each ~ini~hing, moi~ture and cement is redrawn ~o the ~urface o~ the concrete 13. The concrete : 13 become6 harder with every fini~hing.
: The saw 10 can cut the concrete 13 ~t thi~ ti~e and form good grooves. Preferably, the surface of the ~oncrete i~ allowed to air dry ~o the la~t layer of 131~079 moi~ture frolD ~he ~lnishing operation can evaporate. This air drying insures that the we~ght of the 8~1W 10 will not c~use the 6kid plate 24 and the wheels 14-20~ to mark the surface of the concrete 13. This air trying typically S takes from 15 minutes on a warm day, to one hour on a cold day .
It i6 believed that a conventivnal 6aw could not cut concrete ~t this ~tage ~nd produce ~n acceptable surface adjacent the cut groove becau~e of exce~ive ~palling and tO cracking. Further, the weight of Rn abrasive eut~ing machine would cause ~he ~heels of the machi~e to mark the ~urface of the concrete 13. A conventional hand saw with a concrece blade would not have thi~ significatlt weight problem, but such a saw would leave an unacceptable ~agged edge adjacent the cue groove, and its skid plate would mark ehe surface of the concrete 13.
The saw 10 in the illu~trated embod$~ent allow6 the u e of equipment and motors that are considerably li~hter and 1~8s powerful ~han previou~ly used. The saw 10 allows cutting of grooveæ at ~ time which wa~ not prev$ously : con~idered pr~ctica~ or fe~sibLe for cutting grooYes ~n :~ concrete, and wi~h a groove qu~lity that i~ unexpect~d for : the softne~s of the concrete.
The saw la in the illu6trated embodiment allows ~he use of equipment and ~otors that are con~lderable lighter ~nd less powerful than previou~ly used. The ~aw 10 all~w6 cutting of grooves ~t a time which ~a6 not previousl~ considered practical or feaæible ~or cutting ~rooves ~n con~rete, and with a gro~ve quallty that is unexpected for the softn~ss of the concrete.
: Several ee~ts ~ere conducted ln an atte~pt eO more precisely define the hardness of the concre~e 13 wh~ch can be cut by the saw 10 . A 6teel rod weighting 5.75 pounds, and having a diameter of 1.125 inche~, was dropped from a height of ~bout 23.75 inches from the sur~ace of the concrete 130 The rod had a flat end with the 23.75 ~' .

~3~07~

dimension being fro~ the ~urface of the concrete 13 to the flat end of the steel rod. The depeh of the indentation formed by rod ~n the concrete 13 was then ~ea6ured.
For an indentation of about .4 to .5 inches, the ~aw S 10 produced ~ good cut with no rQugh edges adjacent the cut groove. This test ~as conducted with the concrete 13 somewhere in the fresno stage. The wheels 14 through 2D, and the skid plate 24 did leave visible tracks on the surface of ehe concrete 13. Conventional saws would not 10 produce acceptable cuts a~ thi~ ~tage. The ~ater lubricant on ~n ~brasive water 6aw ~ashe~ away the concrete ~nd 180 ehe ag~,re,gate; If the w~er iB not useà, the cut groove fills up with concrete. A conventional rotary hand saw with a blade designed for cutting concrete produces a ~agged cut with partial blockage of the cut, as well as leaving gouges from the plate coneacting the conerete 13.
For a rod indentat~on of abou~ .3 to .4 inches, the ; saw 10 ~till produces a good cut, and the wheel~ 14 through 20 and the skid plate 24 leave ~ery sli&ht marks or Indentations in the 6urface of the con~rete 13.
Conventional ~aws do not work at thi~ hardne~. The water : lubricant from the abrasive saw washes away the concrete and the smaller aggreg~te, but does cut through the larger aggregate ~hich i8 bound by the cemene. A conventional rotary hand &aw with a blade desi~ned for cutting conerete ~till produces a ja~ed cut with partial blockage of the cut, and also leaves ~arks from ~he plate con~artin~ the concrete t3.
30When the rod make~ ~n indentation of about 1/~ of an ~nch, the saw 10 still makes ~ good cut, with a perceptible, but s~all ~ndentation in the concrete fro~
the wheels 14 through 20 and the ~kid plate 24.
: Convention~l saws do not ~o~k ~ince the wa~er lubricated abrasive 6~w ~t~ll wa~hes a~ay the concrete ad;acent the cut groove, and it~ ~heels leave noticeable indentations ~' ,~,, , 13~6~79 in ~he surface of the concrete 13. The mid to large xized aggregate adjacent the surface of the cut ~roove is chipped out of the way leaving cavities. If the water is not used, ~he cut groove fills up wi~h concret0. The conventional rotary hand ~aw ~till leaves a ~agged edge to the cut groove.
When the rod makes a perceptible round indentation of abo~t 113~ to 1/16 of an inch, the saw 10 produces a good quality cut with smooth edges, and almost no perceptible marks ro~ the wheels 14 through 20 and skid plate 24.
Even ~t thls ~tage, the hardness of the concrete i8 not sufficient to allow ~easur2ment by the Swiss Hammer.
Conventional saws ~till do not work at thi6 concrete hardness. The water lubricated abrasive saw leaves ~ cut with rounded edges, and cavitie~ where the aggregate and some surrounding cement are chipped away. If the water is not used, the edges ~re not ~o rounded, but the cavltie~
remain. The conventional ro~ary ~aw with ~ blade designed for cutting concr~te also haQ chipped and sou~h edges, wlth residual cracking around the aggregate adjacent ~he edge o the cut groove.
Conventionsl concrete ~aws, with a blade rotsting at about 1700 rpm, produce a minimally scceptable cut groove when the concrete 13 has reached a hardness well in excess of 1200 pound~ per ~quare inch (psi), as measured by a Swiss Ha~er. This hardne~s typically does not occur until the next day, as previously mentioned. At this hardness, there i6 some chipping and ~oughness a~ the : edge& of the cut groove, but the re~ulting cavities, crack~, and roughne~s are relatively ~msll, r~ng$ng from ~: the ~lze o~ the sand used in the concrete to about 1/8 of ~n ~nch and lar~er.
A conventional rotary 8aW with a blade de~igned to cut concrete, and with a rotational speed of ~bout 11,000 rp~, ~5 does not begln eo produce a cut groove with a quality that i~ ~pproaching ~n acceptable quality, until the concrete _, ...,, ,. ~

_33~ 7~
has reached a hardness of about 1200 psi or higher.
Again, there is some cracking, chipping and r~ughness at the edges of the cut groove, but the size of the cavities and roughness are relatively ~mall as described above.

Claims

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A method of cutting grooves in concrete while providing an acceptable finish, comprising the steps of:
finishing the concrete;
supporting the surface of the concrete being cut during the cutting by use of a support plate immediately adjacent the groove being cut, said support plate having an aperture therein;
placing a rotating cutting blade so it extends through said aperture in order to cut a groove in the concrete, the cutting blade having a cutting edge, a trailing edge, and sides;
controlling the spacing between the sides of the cutting blade and adjacent sides of said aperture so that the surface of the concrete is supported by said supporting step along a sufficient portion of said cutting blade to reduce the damage to the concrete surface at the groove as the concrete is cut; and cutting grooves in the concrete before the concrete has set enough to shrink and crack, said cutting being by an up-cut rotation of said cutting bladeand occurring before said concrete has hardened so that a 1.125 inch diameter steel rod with a flat end, and weighing about 5.75 pounds, would cause an indentation in the concrete of about 1/32 of an inch when the rod is dropped from a height of about 24 inches above the surface of the concrete.
2. A method as defined in Claim 1, wherein said controlling step comprises controlling the spacing between the sides of the cutting blade and the adjacent sides of the aperture so as not exceed 0.125 inches.
3 . A method as defined in Claim 1, wherein said controlling step comprises controlling the spacing between the sides of the cutting blade and the adjacent sides of the aperture do not exceed 0.0625 inches.
4. A method as defined in Claim 2 or 3, further comprising the step of: 35 resiliently urging the cutting blade against the concrete with a predetermined force.
5. A method as defined in Claim 3, further comprising the step of:
resiliently urging the cutting blade against the concrete with a predetermined force; and allowing the cutting blade to move away` from the exterior surface of the concrete when the cutting blade contacts an obstruction in the concrete, so that the cutting blade does not apply sufficient force to the obstruction to damage the concrete finish immediately adjacent the obstruction.
6. A method as defined in Claim 3, further comprising the steps of:
resiliently urging the cutting blade against the concrete with a predetermined force of about 3.0 pounds; and allowing the cutting blade to pivot away from the exterior surface of the concrete when the cutting blade contacts an obstruction in the concrete, so that the cutting Made does not apply sufficient fore to the obstruction to crack the concrete immediately adjacent the obstruction.
7. A method as defined in Claim 2 or Claim 3, wherein the cutting step occurs before the concrete reaches a hardness of about 1200 psi.
8. A method as defined in Claim 2 or Claim 3, wherein the cutting step occurs that same day as the concrete is finished.
9. A method as defined in Claim 2 or Claim 3, wherein the cutting step occurs before the concrete has a hardness such that a 1.125 inch diameter steel rod with a flat end, and weighing about 5.75 pounds, would cause an indentation in the surface of the concrete of about 1/32 of an inch when said rod is dropped from a height of about 24 inches above the surface of the concrete.
10. A method of cutting grooves in concrete comprising the steps of:
finishing the exterior surface of the concrete;

cutting a groove in said surface by a cutting device with a rotating blade having a cutting edge and sides, said cutting step occurring before said concrete has hardened so that a 1.125 inch diameter steel rod with a flat end, and weighing about 5.75 pounds, would cause an indentation in said concrete of about 1/32 of an inch when said rod is dropped from a height of about 24 inches above the surface of said concrete;
rollably supporting the rotating cutting so as to reduce the marking of said concrete surface at said groove during g cutting; and supporting said surface sufficiently close to and along a sufficient portion of said cutting blade to reduce the damage to the concrete surface at said groove as said groove is cut.
11. A method as defined in Claim 10, comprising the further step of:
mounting said cutting blade to allow said blade to move away from said surface in response to said blade contacting an obstruction in said concrete.
12. A method as defined in Claim 10, comprising the further step of:
resiliently urging said blade against said surface in order to cut groove.
13. A method as defined in Claim 10, comprising the further steps of:
resiliently urging said blade against said surface in order to cut said groove; and mounting said cutting blade to allow said blade to move away from said surface in response to said blade contacting an obstruction in said concrete.
14. A method as defined in Claim 10 or 13, wherein said supporting step further comprises:
supporting said surface within 0.125 inches of said cutting blade.
15. A method as defined in Claim 10 or 13, wherein said supporting step further comprises:

supporting said surface within 0.0625 inches of said cutting blade.
16. A method as defined in Claim 10, wherein said cutting step occurs when the concrete has a hardness of less than 1200 psi.
17. A method as defined in Claim 10, comprising the further step of:
supporting said surface within 0.0625 inches of said cutting blade; and wherein the cutting step occurs before the concrete reaches a hardness of about 1200 psi.
18. A method as defined in ally one of Claims 10-13, comprising the further step of:
supporting said surface adjacent said cutting blade; and wherein the cutting step occurs before the concrete has a hardness such that a 1.125 inch diameter steel rod with a flat end, and weighing about 5.75 pounds, would cause an indentation in the surface of the concrete of about .5 to 1/32 of an inch wherein said rod is dropped from a height of about 24 inches above the surface of the concrete.
19. A method as defined in Claim 16 or 17, comprising the further step of:
remotely disengaging said cutting means from said concrete.
20. A method as defined in Claim 10, comprising the further step of:
supporting said surface within 3/32 of an inch of said cutting blade; and wherein the cutting step occurs when the concrete has a hardness below which conventional: concrete saws produce an acceptable cut with minimal chipping at the edges, which hardness typically occurs at a hardness above 1200 psi.
21. A method as defined in Claim 10, comprising the further step of:
supporting said surface within 3/32 of an inch of said cutting blade: and wherein the cutting step occurs before the concrete has a hardness such that a 1.125 inch diameter steel rod with a flat end, and weighing about 5.75 pounds, would cause an indentation in the surface of the concrete of about 1/32 of an inch when said rod is dropped from a height of about 24 inches above the surface of the concrete.
22. A method of cutting grooves in concrete comprising the steps of:
finishing an exterior surface of the concrete;
cutting a groove in said surface with a rotating blade having an up-cut rotation and having a cutting edge and sides, said cutting occurring before said concrete has hardened sufficiently to allow cutting by a conventional abrasive concrete saw, while still producing an acceptable surface finish adjacent the cut groove, said cutting step occurring before the concrete has hardness such that a 1.125 inch diameter steel rod with a flat end, and weighing about 5.75 pounds, would cause an indentation in the surface of the concrete of about 1/32 to 1/2 of an inch when said rod is dropped from a height of about 24 inches above the surface of the concrete;
and supporting said surface within 1/16 to 1/8 of an inch of the sides of said cutting blade, along at least a substantial portion of said blade,to prevent damage to said surface as said groove is cut.
23. A method of cutting grooves in concrete comprising the steps of:
finishing an exterior surface of the concrete;
cutting a groove in said surface with a rotating blade having an up-cut rotation and having a cutting edge and sides, said cutting occurring before said concrete has hardened sufficiently to allow cutting by a conventional abrasive concrete saw, while still producing an acceptable surface finish adjacent the cut groove, said cutting step occurring before the concrete has a hardness such that a 1.125 inch diameter steel rod with a flat end, and weighing about 5.75 pounds, would cause an indentation in the surface of the concrete of about 1/32 to 1/2 of an inch when said rod is dropped from a height of about 24 inches above the surface of the concrete;
and supporting said surface immediately adjacent said sides of said cutting blade within 1/8 of an inch of the sides of said cutting blade, along at least a substantial portion of said blade, to prevent damage to said surface as said groove is cut.
24. A method as defined in Claim 22 or 23, wherein said cutting step occurs when the concrete has a hardness such that said steel rod causes an indentation of about and 1/32 of an inch.
25. A method as defined in Claim 22 or Claim 23, wherein said cutting step occurs when the concrete has a hardness such that said steel rod causes an indentation of about .3 to 1/32 inches.
26. A method as defined in Claim 22, or 23, wherein said cutting step occurs when the concrete has a hardness such that said steel rod causes an indentation of about .3 to .125 inches.
27. A method as defined in Claim 22 or Claim 23, wherein said cutting step occurs when the concrete has a hardness such that said steel rod causes an indentation of about 1/8 of an inch.
28. A method as defined in Claim 22 or Claim 23, wherein said cutting step occurs when the concrete has a hardness below 1200 psi.
29. A method as defined in Claim 22 or Claim 23, further comprising the step of:
pivoting the cutting blade away from the exterior surface of the concrete when the cutting blade contacts an obstruction in the concrete, so that the cutting blade does not apply sufficient force to the obstruction to crack the concrete immediately adjacent the obstruction.
30. A method of cutting grooves in concrete comprising the steps of:
finishing an exterior surface of the concrete;
cutting a groove in said surface with a rotating blade having an up-cut rotation and having a cutting edge and sides, said cutting occurring before said concrete has hardened sufficiently to allow cutting by a conventional abrasive concrete saw, while still producing an acceptable surface finish adjacent the cut groove, said cutting step occurring after said finishing, but before said concrete has a hardness such that a 1.125 inch diameter steel rod with a flat end, and weighing about 5.75 pounds, would cause an indentation in the surface of the concrete of about 1/32 of an inch when said rod is dropped from a height of about 24 inches above the surface of the concrete; and supporting said surface immediately adjacent said sides of said cutting blade within 1/8 of an inch of the sides of said cutting blade, along at least a substantial portion of said blade, to prevent damage to said surface as said groove is cut.
31. A method of cutting grooves in concrete comprising the steps of:
finishing an exterior surface of the concrete;
cutting a groove in said surface with a rotating blade having an up-cut rotation and having a cutting edge and sides, said cutting occurring before said concrete has hardened sufficiently to allow cutting by a conventional abrasive concrete saw, while still producing an acceptable surface finish adjacent the cut groove, said cutting step occurring after said finishing, but before said concrete has a hardness such that a 1.125 inch diameter steel rod with a flat end, and weighing about 5.75 pounds, would cause an indentation in the surface of the concrete of about .5 of an inch to 1/32 of an inch when said rod is dropped from a height of about 24 inches above the surface of the concrete; and supporting said surface immediately adjacent said sides of said cutting blade within 1/16 to 1/8 of an inch of the sides of said cutting blade, along at least a substantial portion of said blade, to prevent damage to said surface as said groove is cut.
32. A method of cutting grooves in concrete as defined in Claim 30 or Claim 31 wherein the finishing to said exterior surface of the concrete is to at least a bull float stage.

33. A method of cutting grooves in concrete as defined in Claim 30 or claim 31 wherein the finishing to said exterior surface of the concrete is to at least a fresno stage.
34. A method as defined in any one of Claims 30, 31, 32 or 33, comprising the further step of remotely disengaging said cutting means from said concrete.
35. A method as defined in any one of Claims 30, 31, 32 or 33, wherein said cutting step occurs before the concrete has a hardness such that said steel rod causes an indentation of about 1/8 of an inch.
36. A method as defined in any one of Claims 30, 31, 32 or 33, wherein said cutting step occurs before the concrete has a hardness such that said steel rod causes an indentation of about .3 inches.
37. A method as defined in any one of Claims 30, 31, 32 or 33, wherein said cutting step occurs before the concrete has a hardness such that said steel rod causes an indentation of between about 1/2 of an inch.
38. A method as defined in any one of Claims 30, 31, 32 or 33, further comprising the step of:
pivoting the cutting made away from the exterior surface of the concrete when the cutting blade contacts an obstruction in the concrete, so that the cutting blade does not apply sufficient force to the obstruction to crack the concrete immediately adjacent the obstruction.
39. A method of cutting grooves in concrete, comprising the steps of:
finishing an exterior surface of the concrete;
cutting a groove in the surface with a rotating blade having an up-cut rotation and having a cutting edge and sides, the cutting occurring before the concrete has hardened sufficiently to allow cutting by a conventional abrasive concrete saw, while still producing an acceptable surface finish adjacent the cut groove, the cutting step occurring when the concrete has a hardness such that a 1.125 inch diameter steel rod with a flat end, and weighing about 5.75 pounds, would cause an indentation in the surface of the concrete of about 1/32 to 1/2 of an inch when the rod is dropped from a height of about 24 inches above the surface of the concrete;
and supporting the surface immediately adjacent the sides of the cutting blade within 1/16 of an inch of the sides of the cutting blade, along a portion of the cutting blade sufficient to prevent damage to said surface as said groove is cut.
40. A method of cutting grooves in concrete, comprising the steps of:
finishing an exterior surface of the concrete;
cutting a groove in the surface with a rotating blade having an up-cut rotation and having a cutting edge and sides, the cutting occurring before the concrete has hardened sufficiently to allow cutting by a conventional abrasive concrete saw, while still producing an acceptable surface finish adjacent the cut groove, the cutting step occurring when the concrete has a hardness such that a 1.125 inch diameter steel rod with a flat end, and weighing about 5.75 pounds, would cause an indentation in the surface of the concrete of about 1/32 to 1/2 of an inch when the rod is dropped from a height of about 24 inches above the surface of the concrete;
and supporting the surface immediately adjacent the sides of the cutting blade within 3/32 of an inch of the sides of the cutting blade, along a portion of the cutting blade sufficient to prevent damage to said surface as said groove is cut.
41. A method of cutting grooves in concrete, comprising the steps of:
finishing an exterior surface of the concrete;
cutting a groove in the surface with a rotating blade having an up-cut rotation and having a cutting edge and sides, the cutting occurring before the concrete has hardened sufficiently to allow cutting by a conventional abrasive concrete saw, while still producing an acceptable surface finish adjacent the cut groove, the cutting step occurring when the concrete has a hardness such that a 1.125 inch diameter steel rod with a flat end, and weighing about 5.75 pounds, would cause an indentation in the surface of the concrete of about 1/32 to 1/2 of an inch when me rod is dropped from a height of about 24 inches above the surface of the concrete;
and supporting the surface immediately adjacent the sides of the cutting blade within 1/8 of an inch of the sides of the cutting blade, along a portion of the cutting blade sufficient to prevent damage to said surface as said groove is cut.
42. A method as defined in Claim 39, wherein the cutting step occurs when the concrete has a hardness such that said steel rod causes an indentation of about 1/32 of an inch.
43. A method as defined in Claim 40, wherein the cutting step occurs when the concrete has a hardness such that said steel rod causes an indentation of about 1/32 of an inch.
44. A method as defined in Claim 41, wherein the cutting step occurs when the concrete has a hardness such that said steel rod causes an indentation of about 1/32 of an inch.
45. A method as defined in Claim 39, wherein the cutting step occurs when the concrete has a hardness such that said steel rod causes an indentation of about .3 to 1/32 of an inch.
46. A method as defined in Claim 40, wherein the cutting step occurs when the concrete has a hardness such that said steel rod causes an indentation of about .3 to 1/32 of an inch.
47. A method as defined in Claim 41, wherein the cutting step occurs when the concrete has a hardness such that said steel rod causes an indentation of about .3 to 1/32 of an inch.
48. A method as defined in Claim 39, wherein the cutting step occurs when the concrete has a hardness such that said steel rod causes an indentation of about .3 to .125 of an inch.
49. A method as defined in Claim 40, wherein the cutting step occurs when the concrete has a hardness such that said steel rod causes an indentation of about .3 to .125 of an inch.

50. A method as defined in Claim 41, wherein the cutting step occurs when the concrete has a hardness such that said steel rod causes an indentation of about 3 to .125 of an inch.
51. A method as defined in Claim 39, wherein the cutting step occurs when the concrete has a hardness such that said steel rod causes an indentation of about 1/8 of an inch.
52. A method as defined in Claim 40, wherein the cutting step occurs when the concrete has a hardness such that said steel rod causes an indentation of about 1/8 of an inch 53. A method as defined in Claim 41, wherein the cutting step occurs when the concrete has a hardness such that said steel rod causes an indentation of about 1/8 of an inch.
54. A method as defined in Claim 39, wherein the cutting step occurs when the concrete has a hardness below 1200 psi.
55. A method as defined in Claim 40, wherein the cutting step occurs when the concrete has a hardness below 1200 psi.
56. A method as defined in Claim 41, wherein the cutting step occurs when the concrete has a hardness below 1200 psi.
57. A method as defined in Claim 40, further comprising the step of pivoting the cutting blade away from the exterior surface of the concrete when the cutting blade contacts an obstruction in the concrete, so that the cutting blade does not apply sufficient force to the obstruction to crack the concrete immediately adjacent the obstruction.
58. A method as defined in Claim 41, further comprising the step of pivoting the cutting blade away from the exterior surface of the concrete when the cutting blade contacts an obstruction in the concrete, so that the cutting blade does not apply sufficient force to the obstruction to crack the concrete immediately adjacent the obstruction.
59. A method as defined in Claim 39, further comprising the step of pivoting the cutting blade away from the exterior surface of the concrete when the cutting blade contacts an obstruction in the concrete, so that the cutting blade does not apply sufficient force to the obstruction to crack the concrete immediately adjacent the obstruction.
60. A method of cutting grooves in concrete, comprising the steps of:
finishing an exterior surface of the concrete to at least a bull float stage;
cutting a groove in the surface with a rotating blade having an up-cut rotation and having a cutting edge and sides, the cutting occurring before the concrete has hardened sufficiently to allow cutting by a conventional abrasive concrete saw, while still producing an acceptable surface finish adjacent the cut groove, the cutting step occurring after the bull float finishing, but before the concrete with a hardness such that a 1.125 inch diameter steel rod with a flat end, and weighing about 5.75 pounds, would cause an indentation in the surface of the concrete of about 1/32 of an inch when the rod is dropped from a height of about 24 inches above the surface of the concrete; and supporting the surface immediately adjacent the sides of the cutting blade within 1/8 of an inch of the sides of the cutting blade, along a portion of the cutting blade sufficient to prevent damage to said surface as said groove is cut.
61. A method of cutting grooves in concrete, comprising the steps of:
finishing an exterior surface of the concrete to at least a bull float stage;
cutting a groove in the surface with a rotating blade having an up-cut rotation and having a cutting edge and sides, the cutting occurring before the concrete has hardened sufficiently to allow cutting by a conventional abrasive concrete saw, while still producing an acceptable surface finish adjacent the cut groove, the cutting step occurring after the bull float finishing, but before the concrete with a hardness such that a 1.125 inch diameter steel rod with a flat end, and weighing about 5.75 pounds, would cause an indentation in the surface of the concrete of about 1/32 of an inch when the rod is dropped from a height of about 24 inches above the surface of the concrete; and supporting the surface immediately adjacent the sides of the cutting blade within 3/32 of an inch of the sides of the cutting blade, along a portion of the cutting blade sufficient to prevent damage to said surface as said groove is cut.
62. A method of cutting grooves in concrete, comprising the steps of:
finishing an exterior surface of the concrete to at least a bull float stage;
cutting a groove in the surface with a rotating blade having an up-cut rotation and having a cutting edge and sides, the cutting occurring before the concrete has hardened sufficiently to allow cutting by a conventional abrasive concrete saw, while still producing an acceptable surface finish adjacent the cut groove, the cutting step occurring after the bull float finishing, but before the concrete with a hardness such that a 1.125 inch diameter steel rod with a flat end, and weighing about 5.75 pounds, would cause an indentation in the surface of the concrete of about 1/32 of an inch when the rod is dropped from a height of about 24 inches above the surface of the concrete; and supporting the surface immediately adjacent the sides of the cutting blade within 1/16 of an inch of the sides of the cutting blade, along a portion of the cutting blade sufficient to prevent damage to said surface as said groove is cut.
63. A method of cutting grooves in concrete, comprising the steps of:
finishing an exterior surface of the concrete to at least a fresno stage;
cutting a groove in the surface with a rotating blade having an up-cut rotation and having a cutting edge and sides, the cutting occurring before the concrete has hardened sufficiently to allow cutting by a conventional abrasive concrete saw, while still producing an acceptable surface finish adjacent the cut groove, the cutting step ocurring after the fresno finishing but before the concrete with a hardness such that a 1.125 inch diameter steel rod with a flat end, and weighing about 5.75 pounds, would cause an indentation in the surface of the concrete of about 1/32 of an inch when the rod is dropped from a height of about 24 inches above the surface of the concrete; and supporting the surface immediately adjacent the sides of the cutting blade within 1/8 of all inch of the sides of the cutting blade, along a portion of the cutting blade sufficient to prevent damage to said surface as said groove is cut.
64. A method of cutting grooves in concrete, comprising the steps of:
finishing an exterior surface of the concrete to at least a fresno stage;
cutting a groove in the surface with a rotating blade having an up-cut rotation and having a cutting edge and sides, the cutting occurring before the concrete has hardened sufficiently to allow cutting by a conventional abrasive concrete saw, while still producing an acceptable surface finish adjacent the cut groove, the cutting step occurring after the fresno finishing, but before the concrete with a hardness such that a 1.125 inch diameter steel rod with a flat end, and weighing about 5.75 pounds, would cause an indentation in the surface of the concrete of about 1/32 of an inch when the rod is dropped from a height of about 24 inches above the surface of the concrete; and supporting ;the surface immediately adjacent the sides of the cutting blade within 3/32 of an inch of the sides of the cutting blade, along a portion of the cutting blade.
65. A method of cutting grooves in concrete, comprising the steps of:
finishing an exertior surface of the concrete to at least a fresno stage;
cutting a groove in the surface with a rotating blade having an up-cut rotation and having a cutting edge and sides, the cutting occurring before the concrete has hardened sufficiently to allow cutting by a conventional abrasive concrete saw, while still producing an acceptable surface finish adjacent the cut groove, the cutting step occurring after the fresno finishing, but before the concrete with a hardness such that a 1.125 inch diameter steel rod with a flat end, and weighing about 5.75 pounds, would cause an indentation in the surface of the concrete of about 1/32 of an inch when the rod is dropped from a height of about 24 inches above the surface of the concrete; and supporting the surface immediately adjacent the sides of the cutting blade within 1/16 of an inch of the sides of the cutting blade, along a portion of the cutting blade sufficient to prevent damage to said surface as said groove is cut.
66. A method of cutting grooves in concrete, comprising the steps of:
finishing an exterior surface of the concrete to a power trowel stage;
cutting a groove in the surface, the cutting step using a rotating blade having an up-cut rotation and having a cutting edge and sides, the cutting occurring before the concrete has hardened sufficiently to allow cutting by a conventional abrasive concrete saw, while still producing an acceptable surface finish adjacent the cut groove, the cutting step occurring after the power trowel finishing, but before the concrete with a hardness such that a 1.125 inch diameter steel rod with a flat end, and weighing about 5.75 pounds, would cause an indentation in the surface of the concrete of about 1/32 of an inch when the rod is dropped from a height of about 24 inches above the surface of the concrete; and suppvrting the surface immediately adjacent the sides of the cutting blade within 1/16 of an inch of the sides of the cutting blade, along at least a portion of the cutting blade sufficient to prevent damage to said surface as said groove is cut and to produce an acceptable surface finish adjacent the cut groove.
67. A method of cutting grooves in concrete, comprising the steps of:
finishing an exterior surface of the concrete to a power trowel stage;
cutting a groove in the surface, the cutting step using a rotating blade having an up-cut rotation and having a cutting edge and sides, the cutting occurring before the concrete has hardened sufficiently to allow cutting by a conventional abrasive concrete saw, while still producing an acceptable surface finish adjacent the cut groove, the cutting step occurring after the power trowel finishing, but before the concrete with a hardness such that a 1.125 inch diameter steel rod with a flat end, and weighing about 5.75 pounds, would cause an indentation in the surface of the concrete of about 1/32 of an inch when the rod is dropped from a height of about 24 inches above the surface of the concrete; and supporting the surface immediately adjacent the sides of the cutting blade within 3/32 of an inch of the sides of the cutting blade, along at least a portion of the cutting blade sufficient to prevent damage to said surface as said groove is cut and to produce an acceptable surface finish adjacent the cut groove.
68. A method of cutting grooves in concrete, comprising the steps of:
finishing an exterior surface of the concrete to a power trowel stage;
cutting a groove in the surface, the cutting step using a rotating blade having an up-cut rotation and having a cutting edge and sides, the cutting occurring before the concrete has hardened sufficiently to allow cutting by a conventional abrasive concrete saw, while still producing an acceptable surface finish adjacent the cut groove, the cutting step occurring after the power trowel finishing, but before the concrete with a hardness such that a 1.125 inch diameter steel rod with a flat end, and weighing about 5.75 pounds, would cause an indentation in the surface of the concrete of about 1/32 of an inch when the rod is dropped from a height of about 24 inches above the surface of the concrete; and supporting the surface immediately adjacent the sides of the cutting blade within 1/8 of an inch of the sides of the cutting blade, along at least a portion of the cutting blade sufficient to prevent damage to said surface as said groove is cut and to produce an acceptable surface finish adjacent the cut groove.
69. A method as defined in any one of Claims 60-68, comprising the further step of remotely disengaging the cutting means for the concrete.
70. A method as defined in any one of Claims 60-68, wherein the cutting step occurs before the concrete has a hardness such that the steel rod causes an indentation of about 1/8 of an inch.
71. A method as defined in any one of Claims 60-68, wherein the cutting step occurs before the concrete has a hardness such that the steel rod causes an indentation of about .3 inch.
72. A method as defined in any one of Claims 60-68. wherein the cutting step occurs before the concrete has a hardness such that said steel rod causes an indentation of about 1/2 of an inch.
73. A method as defined in any one of Claims 60-68, further comprising the step of pivoting the cutting blade away from the exterior surface of the concrete when the cutting blade contacts an obstruction in the concrete, so that the cutting blade does not apply sufficient force to the obstruction to crack the concrete immediately adjacent the obstruction.
74. A method as defined in any one of Claims 60-68, further comprising the step of rollably supporting the cutting blade on the concrete surface.
75. A method of cutting grooves in concrete, comprising the steps of:
finishing an exterior surface of the concrete;
cutting a groove in the surface with a rotating blade having an up-cut rotation and having a cutting edge and sides, the cutting occurring before the concrete has hardened sufficiently to allow cutting by a conventional abrasive concrete saw, while still producing an acceptable surface finish adjacent the cut groove, the cutting step occurring when the concrete with a hardness such that a 1.125 inch diameter steel rod with a flat end, and weighing about 5.75 pounds, would cause an indentation in the surface of the concrete of about 1/32 of an inch when the rod is dropped from a height of about 24 inches above the surface of the concrete; and supporting the surface immediately adjacent the sides of the cutting blade sufficiently close to, and along a sufficient portion, the cuttingblade to prevent damage to the surface as the groove is cut and to produce an acceptable surface finish adjacent the cut groove.
76. A method as defined in Claim 75, comprising the further step of remotely disengaging the cutting means from the concrete.
77. A method as defined in Claim 76, further comprising the step of pivoting the cutting blade away from the exterior surface of the concrete when the cutting blade contacts an obstruction in the concrete, so that the cutting blade does not apply sufficient force to the obstruction to crack the concrete immediately adjacent the obstruction.
78. A method as defined in any one of Claims 75, 76 or 77, further comprising the step of rollably supporting the cutting blade on the concrete surface.
79. A method as defined in Claim 5, further comprising the step of:
resiliently urging the cutting blade against the concrete with a predetermined force; and allowing the cutting blade to move away from the exterior surface of the concrete when the cutting blade contacts an obstruction in the concrete, so that the cutting blade does not apply sufficient force to the obstruction to damage the concrete finish immediately adjacent the obstruction.
80. The method defined in Claim 22 or 23, comprising a further step of remotely disengaging said cutting means from said concrete.
81. A method of cutting grooves in concrete with a cutting device, comprising the steps of:
rotating a concrete cutting blade in an up-cut rotation in a slab of concrete to cut a groove in the surface of the concrete with the cutting blade, the rotating cutting blade having a cutting edge with sides;
supporting the surface of the concrete with a skid plate within 3/32 of an inch of at least said sides of said cutting edge of the rotating concrete cutting blade as the cutting edge leaves the surface of the concrete;
and movably supporting the cutting device on the surface of the concrete by wheels and by said skid plate to distribute the weight of said cutting device on the concrete surface to reduce the marking of the concrete surface at said groove.
82. A method as defined in Claim 81, wherein the concrete is specified to contain aggregate of a predetermined maximum size, and the rotating step comprises cutting the groove to a depth of about 1/2 the size of the largest specified size for the aggregate in the concrete.
83. A method as defined in Claim 81, wherein the concrete is specified to contain aggregate of a predetermined maximum size, and the rotating step comprises cutting the groove to a depth of between about 1/2 the maximum specified aggregate size and .125 inches.
84. A method as defined in any one of Claims 81, 82 or 83, wherein the rotating step occurs before the surface of the concrete has hardened to about 1200 psi.
85. A method as defined in any one of Claims 81, 82 or 83, wherein the rotating step occurs before the surface of the concrete visibly cracks.
86. A method of cutting grooves in uncured concrete with a cutting device, comprising the steps of:
cutting a groove in the surface of the concrete with a cutting device with a rotating concrete cutting blade having an up-cut rotation, the rotating concrete cutting blade having a cutting edge;
supporting the surface of the concrete during cutting by use of a skid plate having a slot positioned relative to the cutting blade such that the surface is supported within .125 inches of the cutting blade along a substantiallength of the cutting blade; and supporting the cutting device on the surface of the concrete during cutting by wheels and by said skid plate.
87. A method as defined in Claim 86, wherein the concrete is specified to contain aggregate of a predetermined maximum size, and the cutting step comprises cutting the groove to a depth of about 1/2 the size of the largest specified size for the aggregate in the concrete.
88. A method as defined in Claim 86, wherein the concrete is specified to contain aggregate of a predetermined maximum size, and the cutting step comprises cutting the groove to a depth of between about 1/2 the maximum specified aggregate size and .125 inches.
89. A method as defined in any one of Claims 86, 87 or 88, wherein the cutting step occurs before the concrete surface has hardened to about 1200 psi.
90. A method as defined in any one of Claims 86, 87 or 88, wherein the cutting step occurs before the concrete surface has visibly cracked.
91. A method of cutting grooves in uncured concrete with a cutting device, comprising the steps of:
finishing the exterior surface of the concrete;
cutting a groove in the surface of the concrete with a cutting device having a rotating concrete cutting blade and an up-cut rotation, the rotating concrete cutting blade having a cutting edge;
supporting the surface during cutting by use of a skid plate having a slot positioned relative to the cutting blade such that the surface is supported within .125 inches of the sides of the up-cutting cutting edge of the cutting blade; and supporting the cutting device on the surface of the concrete by wheels and by said skid plate.
92. A method as defined in Claim 91, wherein the concrete is specified to contain aggregate of a predetermined maximum size, and the cutting step comprising cutting the groove to a depth of between about 1/2 the maximum specified aggregate size and .125 inches.
93. A method as defined in Claim 91, wherein the concrete is specified to contain aggregate of a predetermined maximum size, and the cutting step comprises cutting the groove to a depth of between about 1/2 the maximum specified aggregate size and .125 inches.
94. A method as defined in any one of Claims 91, 92 and 93, wherein the cutting step occurs before the concrete surface has hardened to about 1200 psi.
95. A method as defined in any one of Claims 91, 92 or 93, wherein the cutting step occurs before the concrete surface has visibly cracked.
96. A method of cutting grooves in concrete with a cutting device having a rotating concrete cutting blade, comprising the steps of cutting a groove in the surface of the concrete with a cutting device having a rotating concrete cutting blade with an up-cut rotation, the rotating concrete cutting blade having a cutting edge, the cutting step occurring before the concrete surface adjacent the groove being cut has visibly cracked;
supporting the surface adjacent the up-cutting cutting edge of the rotating concrete cutting blade by use of a skid plate during said cutting step, the concrete surface being supported sufficiently close to and along a sufficient portion of said cutting blade to reduce the ravelling of the groove as said concrete is cut; and supporting the cutting device on the surface of the concrete by wheels and by said skid plate during said cutting step to distribute the weight of said cutting device on the concrete surface to reduce the marking of the concrete surface at the groove.
97. A method as defined in claim 96, wherein the concrete is specified to contain aggregate of a predetermined maximum size, and the cutting step comprises cutting the groove to a depth of about 1/2 the size of the largest specified size for the aggregate in the concrete.
98. A method as defined in Claim 96, wherein the concrete is specified to contain aggregate of a predetermined maximum size, and the cutting step comprises cutting the groove to a depth of between about 1/2 the maximum specified aggregate size and .125 inches.
99. A method as defined in any one of Claims 96, 97 or 98, wherein the supporting step comprises the step of supporting the cutting surface along a substantial length of the cutting blade.
100. A method of cutting grooves in concrete with a cutting device having a rotating concrete cutting blade, comprising the steps of:
cutting a groove in the surface of the concrete without applying fluid to the area being cut, the rotating cutting blade of said cutting device having a cutting edge and an up-cut rotation;
supporting the surface of the concrete adjacent the up-cutting cutting edge of the rotating cutting blade sufficiently close to and along a sufficient portion of said cutting blade to inhibit said surface along said groove from chipping and spalling; and movably supporting the cutting device on the surface of the concrete by using wheels during said cutting step to distribute the weight of said cutting device on the concrete surface to reduce the marking of the concrete surface caused by said step of supporting the concrete during cutting.
101. A method as defined in Claim 100, wherein the concrete is specified to contain aggregate of a predetermined maximum size, and the cutting step comprises cutting the groove to a depth of about 1/2 the size of the largest specified size for the aggregate in the concrete.
102. A method as defined in Claim 100, wherein the concrete is specified to contain aggregate of a predetermined maximum size, and the cutting step comprises cutting the groove to a depth of between about 1/2 the maximum specified aggregate size and .125 inches.
103. A method as defined in any one of Claims 100, 101 or 102 wherein the cutting step occurs before the concrete surface has visibly cracked.
104. A method as defined in any one of Claims 100, 101 or 102 wherein the cutting step occurs before the concrete surface has hardened to about 1200 psi.
105. A method as defined in any one of Claims 100, 101 or 102 wherein the supporting step supports the surface of the concrete along a substantial length of the cutting blade.

106. A method of cutting grooves in concrete with a cutting device having a rotating concrete cutting blade, comprising the steps of:
cutting a groove in the surface of the concrete with a rotating concrete cutting blade without applying fluid to the area being cut, the rotating concrete cutting blade having a cutting edge and an up-cut rotation, the cutting occurring before the concrete has visibly cracked;
supporting the surface of the concrete adjacent the up-cutting cutting edge of the rotating cutting blade, the support being sufficiently closeto the cutting edge and surrounding a sufficient portion of the cutting blade so as to inhibit the concrete surface from chipping or spalling during cutting;
and movably supporting the cutting blade relative to the cutting device to allow movement of the blade out of the concrete if the blade encounters aggregate in the concrete.
107. A method as defined in Claim 106, comprising the further step of movably supporting the cutting device on the surface of the concrete by using wheels during said cutting step.
108. A method as defined in Claim 106, wherein the concrete is specified to contain aggregate of a predetermined maximum size, and the cutting step comprises cutting the groove to a depth of about 1/2 the size of the largest specified size for the aggregate in the concrete.
109. A method as defined in Claim 106, wherein the concrete is specified to contain aggregate of a predetermined maximum size, and the cutting step comprises cutting the groove to a depth of between about 1/2 the maximum specified aggregate size and .125 inches.
110. A method as defined in Claim 106, wherein the cutting step occurs before the concrete surface has hardened to about 1200 psi.
111. A method as defined in any one of Claims 106-109 wherein the supporting step supports the surface of the concrete along a substantial length of the cutting blade.
112. A method of cutting grooves in concrete with a cutting device having a rotating concrete cutting blade, comprising the steps of:

cutting a groove in the surface of the concrete with a rotating concrete cutting blade without applying fluid to the area being cut, the rotating concrete cutting blade having a cutting edge and an up-cut rotation;
supporting the surface of the concrete adjacent at least the up-cutting cutting edge of the rotating cutting blade; and movably supporting the cutting device on the surface of the concrete by using wheels during said cutting step, said two supporting steps provided three locations at which the cutting device is supported on the surface of the concrete.
113. A method as defined in either of Claims 102 or 112, wherein the cutting step occurs before the concrete surface has formed visually perceptible cracks.
114. A method as defined in Claim 112 or 113, wherein the step of supporting the surface of the concrete supports the surface of the concrete along a substantial length of the cutting blade.
115. A method of cutting grooves in the surface of concrete, comprising the steps of:
cutting a groove in the surface of uncured concrete with a rotating cutter of a cutting device; and supporting said device on said concrete surface during said cutting by using wheels and a skid plate.
116. A method as defined in Claim 115, wherein the supporting step further comprises the step of supporting the surface of the concrete adjacent the cutter to inhibit chipping and spalling of the concrete surface as it is cut.
117. A method as defined in Claim 116, wherein the supporting step further comprises the step of supporting the surface of the concrete adjacent the cutter along a substantial portion of the concrete which is in contact with the cutter during cutting.
118. A method as defined in any one of Claims 115, 116 or 117, wherein the cutting step occurs before visually perceptible cracks form in the concrete.
119. A method as defined in any one of Claims 115, 116 or 117, wherein the concrete is specified to contain aggregate of a predetermined maximum size, and the cutting step comprising cutting the groove to a depth of between about 1/2 the maximum specified aggregate size and .125 inches.
120. A method of cutting grooves in the surface of concrete comprising the steps of:
rotating a cutting edge of a concrete cutting blade in the surface of uncured concrete to cut a groove in the concrete; and supporting the cutting blade during said cutting by wheels and by a skid plate sliding on the concrete adjacent the cutting blade.
121. A method as defined in Claim 120, wherein the supporting step further comprises the step of supporting the surface of the concrete within .125 inches of the sides of the cutting edge of the cutting blade during cutting.
122. A method as defined in Claim 121, wherein the supporting step further comprises the step of supporting the surface of the concrete surface adjacent the cutting blade along a substantial length of the cutting blade.
123. A method as defined in any one of Claims 120, 121 or 122, wherein the cutting step occurs before visually perceptible cracks form in the concrete.
124. A method as defined in any one of Claims 120, 121 or 122, wherein the concrete is specified to contain aggregate of a predetermined maximum size, and the cutting step comprising cutting the groove to a depth of between about 1/2 the maximum specified aggregate size and .125 inches.