US2744740A - Rotary cutter and shaft mounting for a pavement cutter - Google Patents

Description

y 1956 c. F. BALL 2,744,740

ROTARY CUTTER AND SHAFT MOUNTING FOR A PAVEMENT CUTTER Filed April 19, 1950 2 Sheets-Sheet 1 INVEN TOR: CHARLES F. BALL ATTORNEY FIG. I.

y 1956 c. F. BALL I 2,744,740

ROTARY CUTTER AND SHAFT MOUNTING FOR A PAVEMENT CUTTER Filed April 19, 1950 2 Sheets-Sheet 2 INVENTOR:

CHARLES F. BALL ATTORNEY United States Patent ROTARY CUTTER AND SHAFT MOUNTING FOR A PAVEMENT CUTTER Charles F. Ball,- Franklin, Pa., assignor to Joy Manufacturing Company, Pittsburgh, Pa., a corporation of Pennsylvania Application April 19, 1950, Serial No. 156,776

Claims. (Cl. 262-20) This invention relates to a pavement cutter, especially to a rotary type pavement cutter.

It often happens in street maintenance and repair work that it is necessary or desirable to remove a portion of the pavement. An improved pavement cutter of the selfmobile type having rotary cutting elements and which enables continuous cutting of the pavement along a closely controlled path, is shown and described in my co-pending application, Serial No. 249,195 filed October 1, 1951, which is a continuation-in-part of the present application.

The present invention is directed particularly to an improved arrangement for mounting the rotary cutters and their associated supporting shaft, and to this end the primary object of the present invention is directed. This and other objects are accomplished in a mobile pavement cutter which mounts one or two cutter wheels on a single shaft. The shaft is provided with two sprockets which are chain-driven by shafts driven through a differential. For smoothest operation of the machine insteelreinforced concrete, the driven sprocket wheels are preferably offset by half a tooth space. A motor such as any suitable internal combustion engine, and preferably one which supplies power to the mobile unit, is provided to drive the one or more cutter wheels.

In the drawings:

Fig. 1 is a plan view with parts in section showing the supporting frame of a pavement cutter assembly and the cutting elements and their supporting shaft;

Fig. 2 is an enlarged sectional view with parts in full of a detail of the cutter shaft showing the mounting of the latter on the frame;

Fig. 3 is a similar view showing the mounting of one of the cutting elements on the shaft; and

Fig. 4 is an enlarged cross-sectional view of the cutter shaft, splined insert and sleeve.

Referring now to the drawings and first to Fig. l, a frame indicated generally at 106 includes a pair of generally longitudinal extending parallel spaced arms 108 one end of each of which is rotatably mounted at each end of a' drive housing 107 which is supported on a main frame (not shown). As is shown in my above mentioned co-pending application Serial No. 249,195, the frame 106 and gear housing 107 may be mounted on the main frame of a mobile truck unit or the like. The two arms 108 are tied together with a cross member 109 to form a doublefork frame, said frame being thus journaled on the housing 107 at one end-i. e., the open end of one of the forks. The other end of the frame-i. e., the open end of the other forkis adapted to receive suitable antifriction bearings 110. A sleeve 111 is journaled in each bearing 110 as is best seen in Fig. 2. An internally splined insert 112 is keyed at its exterior by keys, one of which is shown at 113, to the sleeve 111. A cutter shaft 114 is splined externally to engage the internal splines of inserts 112 and is thus rotatable in the antifriction bearings 110 carried in the open end of one fork of the doublefork frame. A plate 115 is welded to one face of each am 108 at its long end to reinforce the arms and to 2,744,740 Patented May 8, 1956 serve as bearing retainers for bearings 110. Caps 116 screwed or bolted to the other faces serve as bearing retainers on those faces.

In order to avoid wear of the splines in insert 112 and on shaft 114, the outer ends (left end as seen in Fig. 2) of sleeves 111 are machined to fit closely the outer surfaces of the shaft splines. For the same purpose, a smooth collar or sleeve 117 fits the shaft splines closely and fits snugly in the sleeve 111 (at the right end as seen in Fig. 2). Thus the splines do not carry the gravitational load produced by the weight of the shaft 114 and the parts which it supports when the parts are not rotating. In the absence of the support of the shaft by the sleeve 117 and the smaller diameter portion of the sleeve 111 the splines would have their side faces supporting the entire load on the teeth with which they engage in the element 112 and would be carrying a load of which they are entirely freed under static conditions by the construction illustrated. During drive of the shaft there would be a concentration of load on the teeth in the three oclock position during clockwise rotation, in that both the driving load would be transmitted through the sides of the splines which are ahead in the direction of rotation, and also the gravitational load would largely be concentrated on these same surfaces on the splines because the teeth in the nine-oclocl: position would be transmitting a drive through their upper faces and this would be accompanied by a reduction, if not complete elimination, of the transmission of gravitational load through the opposite faces of these teeth. Thus it will be obvious that the provision of the sleeve 117 and the smaller diameter portion of the element 111, providing a journal for the outermost, interrupted surfaces of the shaft 114 will effect an important advantage, one however which is of major importance during actual drive because in the static position of the parts the mere existence of pressure between the side surfaces of the splines and the teeth which they contact on the member 112 will not produce a material wear problem.

The cutter shaft carries one or more rotary tools, here shown as cutter wheels 22 which may desirably be of M the type shown in Patent No. 2,665,893.

,inside diameter of which is splined and which is keyed at 121' on its external diameter to the hub. Splined inserts 112 and 119 are preferably identical. The hub 118 is preferably not clamped to the shaft, but is held against axial displacement along shaft 114 by means of suitable spacers. As assembled in Fig. l, the outer faces of the hubs 118 bear against the inner faces of seals 120, sleeves 111, and collars 117, and the space along the shaft 114 between the inner faces of hubs 118 is filled up by a plurality of spacer sleeves 121 and 122.

Driven sprocket wheels 124 and 126 are secured on and rotate with shaft 114 by being keyed to the sleeves 111 by keys 128. A nut 130 is screwed to the outer end of each sleeve 111 and engages the outer face of its adjacent sprocket wheel 124 or 126. Openings 132 are provided in nut 130 to be engaged by a spanner wrench.

An end cap or plate 134 is bolted to the lower end of shaft 114 (as seen in Fig. l) and a similar end cap 136 is bolted to the upper end of the shaft. End cap 134 is larger in diameter than the shaft and accordingly engages the outside face of sleeve 111 to prevent relative axial movement of sleeve 111 and shaft 114 in one direction.

At the upper end of Fig. 1, it will be noted that shaft 114 has its end 138 projecting considerably beyond the sleeve 111. This extension of shaft 114 is provided in order that a cutter wheel may be mounted on the extension to cut the pavement close to the curb. A sleeve 140 is provided to take up the space between end cap 136 and the outer face of sleeve 111.

gages the outer face of sleeve 111 at the other end of the.

shaft, the shaft is held against displacement crosswise of the pavement cutter.

As will be understood by those skilled in the .art, shaft 114 can be removed without disturbing the bearings 110' and driven sprocket wheels 124 and'126. Thus, cap 136 can be removed, whereupon the shaft 114 can be pulled out to the bottom as seen in Fig. 1. Sleeves 121, 122, and 140, and the cutter wheels 22 drop out and can be reassembled in any desired new orientation, with one cutter wheel at either end of the shaft, for example. Furthermore, it may be noted here that spacer sleeves 121 and 122' are preferably made in the form of split collars, in order that they may be removed without removing shaft 114 and reassembled with the cutter Wheels (either one or both) slid along the shaft in a new arrangement. It will also be evident to those skilled in the art that the shaft 114 can be removed or only partially removed from either end. It may be pointed out that shaft 114 will not usually be pulled'out all the way, but

just enough to remove one cutter wheel or both, as may be desired.

The right end (as seeen in Fig. .1) of each arm 108 is 'provided with ball connections 143 which may desirably form part of a ball and socket joint to connectthe frame 106 to a hydraulically actuated mechanism, which is not shown as it forms no part of the present invention, but which is included as a part of the structure of my aforementioned co-pending application Serial No. 249,195.

Drive for the cutter shaft 114 is taken from any suitable power source, not shown, through a shaft 92 (Fig. 1). The shaft 92 in turn drives out-put shafts 182 and 184 on which'are mounted sprockets 172 and 174 respectively through a conventional differential, not shown, which may be housed in the drive housing 107. Drive is translated from the out- put shafts 182 and 184 to drive sprockets 124 and 126 of the cutter shaft 114 by means of chains 176 and 178. Additional sprocket wheels 202 one of which is preferably mounted on each arm 108 v to cooperate with adjustable sleeve take-up devices 204 tojkeep the drive chains tight are provided. 1

While there is in thisapplication specifically described one form which the invention may assume in practice, it will be under'stood that this form of the same is shown for purposes of illustration, and that the invention may be modified and embodied in various otherforms without departing from its spirit or the scope of'the appended claims.

I claim: I

1. In a cutting machine, a frame having alined open- Bearing and having a smooth bore of a given diameter insert, and at least one key ings, a bearing in each opening, a sleeve journaled in each and a larger diameter bore, an internally splined insert in the larger diameter bore of each sleeve, at least one key in engagement with the insert and the sleeve to hold them against relative rotation, a shaft having external splines closely fitting the given diameter smooth bore of the sleeve and engaging the internally splined inserts, drive means supported on and keyed to the sleeves, and a rotary cutter mounted on the shaft.

2. A machine as in claim 1, .in which .said cutter is mounted on the shaft by means of an internally splined in engagement with the insert and the cutter. 1

3. A machine as in claim 2, in which a second rotary cutter is non-rotatably mounted on the shaft, and removable spacers on the shaft between the cutters.

4. In combination, a frame having alined openings, .a bearing in each opening, a sleeve journaled in each hearing and having a smooth bore of a given diameter and a larger diameter bore, an internally splined insert in the larger diameter bore of each sleeve, at least one key in engagement with the insert and the sleeve to hold them against relative rotation, a shaft having external splines closely fitting the given diameter smooth bore of the sleeve and engaging the internally splined inserts, and drive means supported on and keyed to the sleeves.

5. In combination, a supporting frame, a bearing mounted in the frame, a sleeve journaled in the bearing and having a smooth bore of a given diameter and a larger diameter bore, an internally splined insert .in the larger diameter bore of the sleeve, means in engagement with the insert and the sleeve to hold them against relative rotation, a drive shaft havingexternal splines closely fitting the given diameter smooth bore of the sleeve and engaging the internally splined insert, and drive means supported on and drivingly engaging the sleeve.

References Cited in the file of this patent UNITED STATES PATENTS Crump Oct. 23, 195.1

Images