US3771831A - Pavement cutting machine-cutter bearing assembly - Google Patents

Abstract

Pavement cutting machine having an improved cutter assembly wherein two rotary cutters are arranged end to end. Each cutter has a shaft with bearings at each end of the shaft, the bearings being supported by floating beams each operated by a hydraulic cylinder in order to force the cutter to the work or lift it. The outer end of each shaft has a pulley for a belt connected to an engine to rotate the cutter. The bearing at the outer end of the shaft and adjacent to the drive pulley is a non-expansion selfaligning type bearing arranged to tilt on a fixed axis or point while the bearing at the inner end of the shaft is an expansion self-aligning type bearing to permit horizontal movement of the bearing to thereby relieve stress on the bearings when the cutter shaft is tilted. The floating beams are arranged to pivot on a horizontal axis.

Description

Unite States Patent [191 Hatcher et al.

[4 Nov. 13, 1973 PAVEMENT CUTTING MACHINE-CUTTER BEARING ASSEMBLY [76] lnventors: Cecil W. Hatcher, 1235 Wilson Drive, West Covina; Gene Warner, 8230 Millergrove Drive, Whittier, V V mwbot QfQj hf; [22] Filed: July 31, 1972 [21] Appl. No.: 276,322

[52] US. Cl 299/39, 299/89, 308/19 [5]] Int. Cl. EOlc 23/09 [58] Field of Search 299/39, 89; 308/19 l [56] References Cited UNITED STATES PATENTS 8/1966 l-latcher 299/39 Primary Examiner-Ernest R. Purser Attorney-William E. Beatty [57] ABSTRACT Pavement cutting machine having an improved cutter assembly wherein two rotary cutters are arranged end to end. Each cutter has a shaft with bearings at each end of the shaft, the bearings being supported by floating beams each operated by a hydraulic cylinder in order to force the cutter to the work or lift it. The outer end of each shaft has a pulley for a belt connected to an engine to rotate the cutter. The bearing at the outer end of the shaft and adjacent to the drive pulley is a non-expansion self-aligning type bearing arranged to tilt on a fixed axis or point while the bearing at the inner end of the shaft is an expansion selfaligning type bearing to permit horizontal movement of the bearing to thereby relieve stress on the bearings when the cutter shaft is tilted. The floating beams are arranged to pivot on a horizontal axis.

3 Claims, 10 Drawing Figures 1 PAVEMENT CUTTING MACHINE-CUTTER BEARING ASSEMBLY CROSS-REFERENCE TO RELATED APPLICATION PAVEMENT CUTTING MACHINE, Ser. No. 119,476, filed Mar. 1, 1971 and now U.S. Pat. No. 3,703,316 by Cecil W. Hatcher, et a1.

BACKGROUND OF THE INVENTION 1. Field of the Invention The invention relates to a pavement leveling or grooving machine having a vehicle having a pavement cutter.

2. Description of the Prior Art The prior art includes the machine described and claimed in the patent application identified above and wherein one or two rotary cutter units are used. If two are used, one of the units is supported in advance of the other, with their cutter shafts overlapping at their inner ends. The cutting disks have a certain spacing depending on the use of the machine as a leveling or grooving device. A U-shaped movable frame is pivoted at its front end on a horizontal axis. The outer end of, each cutter unit is supported by the frame or by a floating beam carried by the frame and the same applies to the inner end of each unit. Hydraulic cylinders are provided for raising and lowering the frame andan additional hydraulic cylinder is provided for each of the 30 floating beams. If two cutter units are used, they can be adjusted to a tilt position to substantially fit either the convexity or the concavity of the pavement.

SUMMARY OF THE INVENTION It has been found that when using a cutter in tilt position as described above, undue stress is applied to the bearings for the cutter shaft, resulting at times in bearing failure.

I This is overcome according to the present invention 40 by providing a bearing arrangement which allows relative movement of the element of one bearing with respect to the other bearing. Use is made of a nonexpansion aligning type bearingat the outer end of the cutter shaft adjacent to the drive pulley for that shaft, while employing an expansion aligning type bearing at the inner end of the cutter shaft. When the floating beam for the inner end of the shaft is operated to tilt the inner end of the cutter with respect to its outer end,

the drive pulley is also tilted but this action is so slight 50 that it does not interfere with the proper operation of the drive pulley, the drive pulley being adjacent to the non-expansion type bearing.

BRIEF DESCRIPTION OF THE DRAWINGS trailer assembly showing the bearings according to the present invention.

FIG. 5 is an enlarged fragmentary sectional view taken alone line 5-5 of FIG. 3 showing the bearing construction and with the normal horizontal position of the shaft.

FIG. 6 is a view similar to FIG. 5 but with the shaft tilted.

FIG. 7 is a sectional view taken on line 7-7' of FIG. 6 showing the mounting means for the expansion-type bearing.

FIG. 8 is a sectional view taken along line 8--8 of FIG. 7 showing further construction of the bearing of FIG. 7.

FIG. 9 is a sectional view taken on line 9-9 of FIG. 6 showing the mounting means for the non-expansion type bearing.

FIG. 10 is a sectional view taken along line l0-l0 of FIG. 9 showing further construction of the bearing of FIG. 9.

I DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawings, there is shown in FIG. 1 a tractor-trailer vehicle, generally indicated by the reference numeral 10, comprising a tractor, indicated by numeral 12, a cutter-trailer unit indicated by the numeral 14, and a final trailer unit 16. The complete mobile unit is provided with a typical Diesel or similar engine 18 for moving the vehicle, a vacuum system 20 for recovery of water and concrete cuttings, and a cutter power means 22. Cutter assemblies 24 and 26 and power means 22 are carried by a frame 28. Swivel means, such as a fifth-wheel, are provided to have towing connections between the units. These are shown'as 30 and 32. A water pump unit 34 provides water to the cutting operation. Forward steerable wheels 36 and back drive wheels 38 are provided on tractor 12. Tandem wheels 40 on frame 28, and wheels 42 on tractor -16. A trailertype ball hitch 44 is provided on frame 28 (see FIG. 3) for the purpose of supporting a frame assembly 46 and allowing tilting about axis a-a (as shown in FIG. 3). Frame assembly 46 generally has an end beam 47 and a U-shaped member 48. Hydraulic cylinders 50a and 50b are provided to raise frame member 48 about pivot points 520 and 52b. A pair of floating beams 54a and 54b are mounted on pivot points 580 and 58b on frame 46, and are actuated together or independently by hydraulic cylinders 56a and 56b. Downward-most movement of these floating beams is limited by U-shaped straps 60a and 60b mounted on the U-shaped frame 48.

Cutter assemblies 24 and 26 are mounted onto and between U-shaped frame 48 and floating beams 54a and 54b by pairs of bearings. As seen in FIGS. 3 6 an expansion type self-aligning bearing 62a and a nonexpansion type self-aligning bearing 64a support the cutter assembly 26. Similarly, an expansion type selfaligning bearing 62b and a non-expansion type selfaligning bearing 64b support cutter assembly 24. Bearings 64a and 64b are carried by pillow blocks like 66 on the opposite sides .of the U-frame 48 while bearing 62b is carried by a pillow block like 66 on the floating beam 54a while bearing 62a is supported on a pillow block like 66 -on floating beam 54b.

- 6 FIG. 4 is a partial perspective view of the grooving 5 Typically, as shown in FIGS. 5 and 6, the nonexpansion type bearings 64a and 64b each has a bearing housing like 164 and an inner-outer race construction within this housing as described later.

at 76a, 76b, 76c, and 76d as described and claimed in I 78a and an outer race 78b confining a set of rollers 79 therein. The internal spherical surface of the housing body is indicated by the reference numeral 80 and the mating outer surface of outer race 78b indicated by the numeral 81. The races can rotate with respect to each other, and can also tilt for self-alignment about a point P which is the center of surface 80. The inner race 78a is fixed to the shaft 70 by means of two retaining rings 85a, 85b positively fixed to the shaft by set screws 85c. Self-alignment is limited in scope by a lubricating- Iimiting pin 82 in housing opening 83 (see FIG. 6). A cap 84. is provided for access to lubricate.

As shown in FIGS. 6, 7, and 8, bearing 62b has inner race 86a and outer race 86b with rollers 87 confined therein. Exterior spherical surface 88 of outer race 86b allows self-alignment of the bearing within a cylindrical opening 89. This allows horizontal movement of the inner-outer races within the housing as the floating beam 540 is raised to a higher position by the hydraulic cylinder 56a. As shown in FIG. 6, the bearing races can still support the shaft 70 without binding, which formerly resulted in bearing failures. The angle designated 100 in FIG. 6 shows the upward movement allowed for shaft 70 from the horizontal axis b-b. Bearing 62b has a reduced diameter 90 providing a stop-shoulder for the excessive movement of bearing races 86a, 86b. A limit lube-pin 92 is provided in opening 94 as in the other bearing 64b. Retaining rings 92a and 92b are'provided for retaining the bearing to the shaft by means of set screws 92c. Additionally, a cap 95 allows access for lubrication.

Bearing 62b for shaft 70 is fixed to a pillow block 66b by bolts 96b as shown in FIG. 7. Bearing64b also for shaft 70 is fixed to pillow block 66a. The two bearings for shaft 71 are similarly fixed to their pillow blocks 66c and 66d. Pillow blocks 66a and 66d are suitably fixed to the side members of the U-frame 48. The pillow block 66b is suitably fixed to floating beam 65a for the inner end of shaft 70. Pillow block 660 is suitably fixed to floating beam 54b for the inner end of shaft 71.

Each hearing has a housing in two parts 110, 1 l 1 (see FIG. 7) secured together with bolts like 112.

As shown in FIG. 3, guide flanges 102a and 102b are provided on frame 28 for the purpose of vertically guiding frame assembly 48 from excessive sideways movement. These guide flanges confine a guide pin 104 which is fixed to frame 48.

Auxiliary wheel assemblies 106a and 106b are also provided on the floating beams 54a and 54b to more effectively control depth cutting of the cutting heads.

Stress on the bearings for each shaft is relieved when the shaft is tilted as shown in FIG. 6.

The invention may be applied to a single cutter or to a plurality of cutters. In operation, the bearing supports permit the cutter shaft to assume a tilt position out of true horizontal position to fit the slope or contour of the pavement. In assuming the tiltposition, the distance between the bearings at the opposite ends of the cutter is increased, while undue stress on the bearings is reduced or prevented at this time by the bearing arrangement of the present invention.

We claim:

1. Cutter assembly comprising a rotary cutter havinga shaft, a first support having a first bearing for a first end of said shaft, a second support having a second bearing for a second end of said shaft, means supporting said first and second supports for pivotal movement on a horizontal axis, a drive pulley on a first end of said shaft adjacent said first bearing, means for operating said drive pulley, and separate and independent means for operating said supports, the improvement wherein said first bearing has a housing body having an internal spherical surface, said body having an inner race and an outer race confining a set of rollers, the outer surface of said outer race having a spherical surface mating with the internal spherical surface of said housing body, said races tilting for self-alignment about a fixed point which is the center of said spherical surfaces, said second bearing having a housing body having an internal cylindrical surface housing a roller bearing for said shaft, said roller bearing having an external spherical surface supported for longitudinal movement and tilt movement by said cylindrical surface for expansion of said second bearing withrespect to said first bearing.

2. In a cutter assembly having a U-frame having opposite sides and a pair of floating beams intermediate said sides, separate means supporting the outer ends of said sides and said beams for pivotal movement on a transverse horizontal axis and on a longitudinal axis, a rotary cutter having a first shaft, bearings supporting opposite ends of said shaft in one side of said U-frame and one of said floating beams, another rotary cutter having a second shaft, bearings supporting opposite ends of said second shaft in the other said beams and in the other side of said U-frame, a pulley on each of said shafts adjacent to 'a side of said U-frame, and means for operating said drive pulleys, fluid pressure operated means operating said frame and each of said beams, the improvement wherein the bearing in each side of said U-frame has parts with mating spherical surfaces relatively movable on a fixed center, and wherein each bearing in one of said beams has a housing body having an internal cylindrical surface housing a roller bearing for said shaft, each said roller bearing having an external spherical surface and each roller bearing being supported for longitudinal movement and tilt movement by its said cylindrical surface.

3. Cutter assembly comprising a rotary cutter having a shaft, a bearing at each end of said shaft, means for rotating said shaft, a movable support for each of said bearings, -separate fluid pressure operated means for operating each of said supports to hold said cutter in active position on a pavement, said cutter tilting out of true horizontal position to fit the contour of the pavement, and one of said bearings having members having a slidable coupling to relieve the stress between said bearings when the distance between said bearings increases as said shaft assumes a tilt position, said one bearing having a housing body having an internal cylindrical surface housing a roller bearing for said shaft, said roller bearing having an external spherical surface supported for longitudinal movement and tilt movement by said cylindrical surface.

Claims (3)

1. Cutter assembly comprising a rotary cutter having a shaft, a first support having a first bearing for a first end of said Shaft, a second support having a second bearing for a second end of said shaft, means supporting said first and second supports for pivotal movement on a horizontal axis, a drive pulley on a first end of said shaft adjacent said first bearing, means for operating said drive pulley, and separate and independent means for operating said supports, the improvement wherein said first bearing has a housing body having an internal spherical surface, said body having an inner race and an outer race confining a set of rollers, the outer surface of said outer race having a spherical surface mating with the internal spherical surface of said housing body, said races tilting for self-alignment about a fixed point which is the center of said spherical surfaces, said second bearing having a housing body having an internal cylindrical surface housing a roller bearing for said shaft, said roller bearing having an external spherical surface supported for longitudinal movement and tilt movement by said cylindrical surface for expansion of said second bearing with respect to said first bearing.

2. In a cutter assembly having a U-frame having opposite sides and a pair of floating beams intermediate said sides, separate means supporting the outer ends of said sides and said beams for pivotal movement on a transverse horizontal axis and on a longitudinal axis, a rotary cutter having a first shaft, bearings supporting opposite ends of said shaft in one side of said U-frame and one of said floating beams, another rotary cutter having a second shaft, bearings supporting opposite ends of said second shaft in the other said beams and in the other side of said U-frame, a pulley on each of said shafts adjacent to a side of said U-frame, and means for operating said drive pulleys, fluid pressure operated means operating said frame and each of said beams, the improvement wherein the bearing in each side of said U-frame has parts with mating spherical surfaces relatively movable on a fixed center, and wherein each bearing in one of said beams has a housing body having an internal cylindrical surface housing a roller bearing for said shaft, each said roller bearing having an external spherical surface and each roller bearing being supported for longitudinal movement and tilt movement by its said cylindrical surface.

3. Cutter assembly comprising a rotary cutter having a shaft, a bearing at each end of said shaft, means for rotating said shaft, a movable support for each of said bearings, separate fluid pressure operated means for operating each of said supports to hold said cutter in active position on a pavement, said cutter tilting out of true horizontal position to fit the contour of the pavement, and one of said bearings having members having a slidable coupling to relieve the stress between said bearings when the distance between said bearings increases as said shaft assumes a tilt position, said one bearing having a housing body having an internal cylindrical surface housing a roller bearing for said shaft, said roller bearing having an external spherical surface supported for longitudinal movement and tilt movement by said cylindrical surface.

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