Patent Application
20060105681
The present invention relates generally to an apparatus for grinding an out-of-round trunnion or tire for a rotary kiln and, more particularly, to a self-adjusting assembly for grinding an out-of-round trunnion or tire into round.
Tubular rotary kilns are commonly used in the manufacture of cement and pulverized lime and in drying other solid and granular materials. The kilns are supported and rotate on trunnion roller mountings that cooperate with a tire surrounding the shell of the kiln.
Wear on the trunnion rollers is an inevitable consequence of the friction that occurs between the kiln tire and the trunnion rollers. At some point, either the kiln tire or the trunnion rollers will become out-of-round (usually concave). There are several negative consequences to an out-of-round kiln tire or trunnion roller. First, as the wear continues, the contact surface on the kiln tire and the trunnion roller decreases, and the kiln becomes difficult to control. Second, since the trunnion roller turns approximately three times for every revolution of the kiln tire, the surface of the trunnion roller will become harder than the surface of the tire as a result of work hardening. When the hardness relationship between the kiln tire and the trunnion roller is out of balance, spalling occurs on the surface of the kiln tire. Third, if the surfaces of the kiln tire and the trunnion rollers wear to the point that the kiln is not free to move uphill or downhill on the surface of the trunnion roller, the kiln will move in the direction of the kiln thrust. Thus, the shaft of the trunnion roller is forced against a thrust collar or thrust plate and high-heating temperatures will result. Fourth, wear on the surface of the tire or trunnion roller ultimately reduces the operating efficiency of the kiln, and, thus, unnecessarily increases the consumption of energy.
A need exists for a machine to be used on-site to address both the wear of kiln tires and trunnion rollers to place them back in round.
It is the object of the invention to provide an apparatus for grinding an out-of-round kiln tire or trunnion roller for a rotary kiln back into round. In accordance with this and other objects of the invention, there is provided a mounting bracket for straddling a trunnion roller when the apparatus is grinding an out-of-round kiln tire, a grinding wheel assembly, a means for positioning the grinding wheel assembly in tangent relation to the out-of-round trunnion or tire, and a means for tracking an outside diameter of the out-of-round trunnion roller or kiln tire. The mounting bracket includes a base weldment, a linear mill mount coupled to the base weldment and an assembly for urging the means for tracking an outside diameter against the out-of-round tire trunnion roller or kiln tire. Said means for urging includes an air cylinder operatively coupled to an air cylinder mount which is attached to the linear mill mount. The air cylinder is urged against a channel which is secured to the linear mill mount. The grinding wheel assembly comprises a grinding wheel, a drive assembly for rotating the grinding wheel and a housing for shielding the drive assembly. The means for positioning the grinding wheel assembly so that it is in tangent with the out-of-round trunnion roller or kiln tire includes a cross feed member for translating the grinding wheel head assembly along a first axis, a saddle for the grinding wheel assembly and a means for positioning the saddle at an angle. The means for positioning the saddle at an angle includes a bottom assembly for translating the saddle along a second axis and a top assembly for translating the saddle along a third axis. The means for tracking the diameter of the out-of-round trunnion roller or kiln tire includes a roller which is operatively coupled to the grinding apparatus.
The above and other objects and advantages of the invention will be more readily apparent from the following detailed description when considered with the accompanying drawing wherein;
a is a partial exploded view showing the grinding wheel head assembly and the positioning assembly;
b is an exploded view of the tracking assembly and a partial exploded view of the positioning assembly;
c is an exploded view of the positioning assembly and mounting brace;
A grinding apparatus for grinding an out-of-round trunnion roller or kiln tire is shown in
The base weldment 20 supports a linear mill mount 28 which in turn supports the positioning means.
The linear mill mount 28 urges the grinder assembly 10 toward the out-of-round trunnion roller of kiln tire. An air cylinder 30 passes through an air cylinder mount 32 which is coupled to the linear mill mount 28. The air cylinder 30 has a threaded end 36. The threaded end 36 intersects with threaded end bracket 40. The threaded end bracket is fastened to a base plate 42 by a pair of cylindrical rails 38 that arc, in turn, secured to linear mill mount 28 by a first grouping of pillow blocks 40(a), 40(b), 40(c) and 40(d). The means for positioning the grinding wheel head assembly so that the grinding wheel is tangent to the out-of-round trunnion roller or kiln tire comprises a cross feed member, a saddle and a means for positioning the saddle at an angle. The cross feed member designated by numeral 41 in
The positioning means serves two functions. First, as previously described, it aligns the grinder head assembly 14 with the trunnion roller or kiln tire. Second, it positions the grinder head assembly 14 so that it is in tangent with the trunnion roller or kiln tire. To that end, the positioning means has a bottom assembly, a top assembly and a pivoting assembly for adjusting the tilt angle of the grinder head assembly 14 so as to be tangent to the trunnion roller or kiln tire. The bottom assembly comprises a lower plate 62 having a pair of width side edges 64a and 64b and a pair of length side edges 66. A u-shaped groove 68 or channel is formed in the center of the top surface of lower plate 62. A pair of lower plate bars single edge slides 70 are fastened along the length edges 66 of lower plate 62. Lower bracket plate 72 is coupled to the first width end 64(a). A second feed screw 74 is disposed in the unshaped groove 68 and is journaled for rotation in the lower bracket plate 72. A second feed nut 76 is operatively coupled to the second feed screw 74 such that rotation of the second feed screw 74 translates the second feed nut 76 along the second feed screw 74. Second feed nut 76 is coupled to angle plate saddle 78 which slides along the lower plate single edge slides 70 when the second feed screw 74 is rotated. The lower plate 62 is mounted on the cross feed saddle 58 such that when the cross feed saddle is translated across base plate 42 by feed screw 52 the bottom assembly moves with it.
Saddle 78 is mounted to a top assembly. The top assembly includes a rectangular upper plate 80, which has a first width end 82(a) and a second width end 82(b), and two length-side edges 84 and a u-shaped groove or channel 86 that extends inward from the first width end 82(a) on the top surface of upper plate 80 proximate the center thereof. Upper plate slide edges 88 are fastened to the upper plate length-side edges 84 and upper bracket plate 90 is bolted to the first width edge 82(a) of the plate 80. Third feed screw 92 is journaled for rotation within the u-shaped groove 86. The third feed screw 92 is secured to the upper bracket plate 90 by a jam nut 96 and an oil impregnated bearing 98, with a thrust bearing 100 hex nut 102, bearing lock nut 106 and bearing lock washer 104 completing the assembly. (Second feed screw 74 is secured to the lower plate bracket 72 in an identical manner.) A third feed nut 94 is threaded onto third feed screw 92.
A control saddle 108 is mounted on the upper plate 80 and is translated across the length dimension of the upper plate by the cooperation of the third feet nut 94 with a mating recess (not shown) formed in the undersurface of the control saddle 108. The bottom assembly and the top assembly are connected to one another by a pivot assembly. The pivot assembly includes jack leg brackets 110. Each jack leg bracket 110 has a first end 112 and a second end 114. Each of the second ends 114 of the two jack leg brackets 110 is secured to the side edges of the angle plate saddle 78. They are secured by a hinge pin 118 which passes through the second end 114 and is locked into place by a washer 116 and a nut 120. The first ends 112 of the jack leg brackets 110 are secured to the rectangular upper plate 80 in a similar manner.
In addition, the lower plate 62 and the upper plate 80 are secured to one another by hinge member 111 (
The exploded view of the grinding head assembly 14 shown in
The drive assembly has a motor 144 whose shaft 147 is coupled to a first taper lock sheave 146. The motor shaft 147 passes through oblong aperture 136 of the sheave side shield and is coupled to first taper lock sheave 146 and it is secured by tapered bushing 148. Running parallel to the motor 144 is arbor 150 which passes through pillow blocks 160a and 160b and circular aperture 138 in the sheave cover shield 134. A second sheave 154 is attached to first end of the arbor 150 and is held there to by second tapered bushing 156. A plurality of endless belts 158 wrap around first sheave 146 and second sheave 154 such that rotation of motor shaft 147 is transferred to the arbor 150 by rotation of the sheaves 146, 154 and the belt 158.
The arbor 150 is supported and journaled in pillow blocks 160(a) and 160(b). Disposed at the second end 154 of the arbor 150 is grinding wheel hub 161. The hub 161 is bolted to a flange 163 on the second end of the arbor along with the grinding wheel 124. Thus, the motor rotates the arbor 150, which in turn rotates the grinding wheel 124. The entire assembly is supported by the grinder motor base plate 162.
When fully assembled, the sheave cover 130 covers the first and second sheave 146 and 154, the first and second tapered bushing 148 and 156, as well as the belt 158. The sheaves are separated from the motor 144 and pillow blocks 160(a) and 160(b) by the sheave side shield 134. Pillow block cover 132 covers the pillow blocks 160(a) and 160(b) as well as the portion of the arbor shaft extending between the pillow blocks. The remainder of arbor 150 is covered by the moveable shield 140 and the hub 160 and outside diameter of the grinding wheel 124 are covered by the upper and lower grinding wheel shield 142(a) and 142(b). Base plate 162 is mounted to the spacer 60 that fastens to the saddle member 108 (
A tracking assembly tracking an outside diameter of an out-of-round trunnion roller or kiln tire is a first and second contact wheel 18a and 18b. The contact wheels 18a and 18b are held by roller brackets 164. The roller brackets 164 are coupled together by adjustable pivot arm 166. A roller arm 168 is coupled to the bottom side of the base plate 42 by locking tube 170. The roller brackets 164a and 164b are coupled together by adjustable roller pivot arm 172. The adjustable roller pivot arm 172 is coupled to the roller pivot bracket 176. The roller pivot bracket 176 is in turn coupled to the roller arm 168 so that the roller pivot bracket 176 pivots as the contract wheels 18a, 18b track the trunnion roller or kiln tire.
In order to machine an out-of-round trunnion roller, the grinding apparatus 10 is placed adjacent to the trunnion roller. The air ram 30 urges the tracking wheel 18, along with the entire assembly against a trunnion roller. The grinder head assembly 14 is placed in tangent to the trunnion roller and as the trunnion roller is rotated, the grinding wheel 12 grinds the out-of-round trunnion until it is back into round.
The grinding apparatus 10 can also be used to grind a kiln tire as well. To machine a kiln tire the grinding apparatus 10 is positioned to straddle a trunnion roller. Travel stop block 200 is rigidly mounted to linear mill mount 20. Travel stop block has a travel block aperture 202. A jacking plate 204 is fastened to the bottom of base plate 42. Jacking plate 204 has a jacking plate aperture 206. The travel block aperture 202 is aligned with jacking plate aperture 206 and are bolted together by bolt 208. When the jacking plate 204 is fastened to travel stop block 200 the grind apparatus 10 will not track. The tracking rollers 18a and 18b are removed, and the air ram is not energized. The grinder head assembly 14 is placed in tangent to the kiln tire, and as the kiln tire rotates, the grinding wheel 124 grinds the kiln tire until it is made round.
This invention has been describe herein in considerable detail and in order to comply with the Patent Statutes and to provide those skilled in the art with the information needed to apply the novel principles and to construct and use such specialized components as are required. However, it is to be understood that the invention can be carried out by specifically different equipment and devices, and that various modifications, both as to the equipment and operating procedures, can be accomplished without departing from the scope of the invention itself.
