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Publication numberUS3455065 A
Publication typeGrant
Publication dateJul 15, 1969
Filing dateDec 23, 1965
Priority dateDec 23, 1965
Publication numberUS 3455065 A, US 3455065A, US-A-3455065, US3455065 A, US3455065A
InventorsHashimoto Kazuo, Shiomi Hajime
Original AssigneeJapan National Railway, Kishaseizo Kk
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Grinding machine for railroad cars
US 3455065 A
Abstract  available in
Images(8)
Previous page
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Claims  available in
Description  (OCR text may contain errors)

July 15, 1969 l-IAJIME SHIQMI ET AL v 3,455,065

I GRINDING MACHINE FOR RAILROAD CARS Filed Dec. 19.55 8 Sheets-Sheet 1 H SHLoMI A4 0 K #ASHIMOTo INVENTORS Wm, M I/M A Tram/E rs July 15, 1969 HAJIME SHIOMI ET AL 3,455,065

GRINDING MACHINE FOR RAILROAD CARS Flled Dec. 23. 1965 8 sh t -sheet 2 BY UM July 15, 1969 HAJIME SHIOMI ETAL 3, ,06

GRINDING MACHINE FOR RAILROAD CARS Filed Dec. 23, 1965 8 e ts-Sheet s H Sf/IOMI AuD K //A.SHIMOT0 mvsmoxs BY M2 2 76m A TTJRfVErS y 1969 HAJIME SHIOMI ET AL 3,455,065

GRINDING MACHINE FOR RAILROAD CARS v 8 Sheets-Sheet 5 Filed Dec. 23, 1965 FIG. 7.

H. SHIOMI AND K. HASHIMoTo INVENTORS BYMMim/m Arm/vs Ks July 15,1969 mums SHIOMI ET AL 3, 5

GRINDING MACHINE FOR RAILROAD CARS Filed Dec. 23, 1965 8 sheets sheet 6 FIG. 8.

H Suzom o K HAsHIMoro INVENTORS BY Mum ATTOZNHS y 5, 1969 mums smom ET m. 3,455,065

GRINDING MACHINE FOR RAILROAD CARS Filed Dec. 23, 1965 8 Sheets-Sheet 7 FIG. I0.

IOI

I02 A 407 I03 "5 1 p09 J H6 I n ggqjzo H SHZOMI AND K, HAsHI/msra INVENTOR5 July 15, 19 9 Filed Dec. 23, 1965 HAJIME smom ETAL GRINDING MACHINE FOR RAILROAD CARS a Sheets-Sfieet a H- SHIoMI MD K f/ASl/IMdTd INVENTORS il/10354, iii/UM Arron/5x5 United States Patent US. Cl. 51104 9 Claims ABSTRACT OF THE DISCLOSURE A grinding machine for railroad car wheels. A fix d frame is mounted on a bed and roller supporting frames are movable up and down along sliding surfaces on the fixed frame and are also movable back and forth on said sliding surfaces. A plurality of wheel driving rollers adapted to receive wheel flanges of railroad car wheels are mounted on the top portion of each of the roller supporting frames, there being a pair of rollers at positions corresponding to the ends of a railroad car axle. The roller supporting frames can thus be moved up and down and back and forth in order to be correctly positioned beneath the wheel flanges so that the wheels can be properly supported for grinding by grinding means also mounted on the apparatus.

The present invention relates to a grinding machine for grinding railroad car wheels, which machine grinds the treads of the wheels with the wheel bearings used as a reference for the grinding, while the weight of cars is borne by supporting the journal boxes of railroad cars having their wheels mounted thereon on a supporting portion of the grinding machine. The present invention further relates to an improved feeding device for the grinding member which is advantageously used in the present machine.

Usually grinding of treads of railroad car wheels is carried out at the time of a regular inspection by removing the wheels from the car. Recently it has become necessary, because the speed of railroad cars has been increasing, to grind the wheel treads into proper shape more frequently in order to maintain the cars in good operating condition at all times.

In this case it is very efficient to perform such grinding with the wheels mounted on the car bodies, because this enhances efficiency in the utilization of the railroad cars. For this reason various types of under-floor type wheel truing machines are being used.

These machines utilize as the reference for the grinding operation a system such as one which holds the center hole of axle for the wheels, one which supports the wheel at its circumference by means of rollers, and a bearing base system to support a journal box on a fixed part of the machine, etc.

Among these systems, the bearing base systems have a good efficiency and are easy to operate, and high precision grinding can be carried out because the wheels are ground almost under their running conditions.

The present invention has as one object the provision of a wheel grinding machine by which the advantages of this last mentioned system are enhanced to the maximum degree. One purpose of the present invention is to provide an apparatus which can make a rough adjustment in determining the position of the wheels of a railroad car which is rolled, either by being self-propelled or drawn, into the maintenance shop track for the purpose of having the wheels ground. The apparatus consists of a fixed rail connected to a track up to the position of grinding machine and a movable rail, the car being positioned on the track in such manner that the center between front and 3,455,065 Patented July 15, 1969 rear Wheel axles will come to the center of the grinding machine, and the car can be lifted off the rail by supporting the flange portion of the wheels in wheel driving rollers which are attached to a roller supporting frame, as the frame is raised vertically by, for example, hydraulic cylinders.

Another object of the present invention is to provide a wheel inner face adjusting apparatus which makes a minute adjustment in the position of wheels with respect to the dimension between the inner faces of the left and right wheels in the direction perpendicular to the rail, i.e. in the direction of the axle, by holding the adjusting rollers on one side of the car in a fixed or base position by, as an example, cylinders containing hydraulic oil, and pushing the inner face of a 'Wheel mounted in the rollers on the other side of the car outwardly a distance equal the difference from the standard of the dimension between the inner faces the two-Wheels, and at the same time moving the said wheel driving rollers in the direction of the axle.

A still further object of the present invention is to provide an apparatus which will support the axle firmly on its journal box on the supporting part of a member on the said movable rail which is pushed outwardly during the grinding operation, and while the driving rollers are always in contact with the circumference of wheel following its eccentricity and distortion and with the wheel bearings used as a reference for grinding, and thereby giving an effective rotating force to the wheel, will adjust the position of the grinding tool, thus conducting proper and improved grinding. Another object of the present invention is to provide an improved feeding device for the machine member to be used in the grinding machine.

A preferred embodiment of the grinding machine of the present invention in the form of a wheel grinding machine of the fixed under-floor type which grinds railway car wheels with grinding wheels will be explained in reference to the accompanying drawings, in which FIG. 1 is a plan view showing an embodiment of the present invention;

FIG. 2 is a longitudinal sectional view taken along line 22 in FIG. 1;

FIG. 3 is an end elevation view of the embodiment of FIG. 1;

FIGS. 4, 5 and 6 are the schematic views showing the positions of the wheels and the grinding machine in relation to each other;

FIG. 7 is a schematic view showing the relationship between the wheels and their driving rollers;

FIG. 8 is a detailed sectional view of a wheel driving roller;

FIG. 9 is a schematic end view showing the action of the rollers regulating the positions of the rear faces of the wheels;

FIG. 10 is a side view, partly in section, of the feed system for the machining devices used in the present invention; and

FIG. 11 is a cross-section taken along line 1111 of FIG. 10.

As is shown in FIG. 1, the machine is made in two parts which are integral, i.e., part A for the front wheels and part B for the rear wheels, both parts having an identical construction and parts, and the distance between the centers of parts A and B being the same as between two axles of a bogie.

In FIG. 1, FIG. 2 and FIG. 3, a bed 1 is fixedly placed on a foundation, and columns 2 are mounted at four places 2 on each side. And a fixed frame 3 is mounted on the bed 1, and roller supporting frames 4 go up and down along sliding surfaces 8 which are provided on the sides of the frame 3. Grinding wheel heads '5 have grinding wheels 6 attached thereto, which heads go up and down within the columns 2. The position of the heads can be adjusted to correspond to the direction of axle. The tops of columns 2 are covered with crossframes 7.

As shown in FIG. 1, wheel driving rollers 9 and a driving mechanism 10 which drives and rotates the rollers are firmly mounted on the roller supporting frames 4 such that two sets of rollers on each end of an axle or a total of four rollers per axle are placed in an appropriate position at the same distance from the vertical central axis of roller supporting frames 4.

Fixed rails 11 and 11 are provided for rolling a railroad car to the position of the wheel grinding machine, being connected to rails 12 and 12' which in turn are fixed to the floor of a plant, and extend to the top of columns 2 across a pit 13. A fixed rail 45 is also installed between the columns 2 of parts A and B. Members 14 are mounted on the cross-frames 7, having a movable rail 34 thereon, and they are so constructed that they can go back and forth for a predetermined distance in a direction perpendicular to the rail 45 under the action of hydraulic cylinders 15. In its forward position, the movable rail is aligned with fixed rails 11, 11' and 45 to form a continuous rail onto which a railroad car can be rolled. The member 14 is so made that at its withdrawn or rear position (FIG. 1), a journal box supporting block 16, which is integral with the top of the member 14 on which the movable rail is mounted, is positioned just underneath the journal box of an axle to carry the weight of the car body, and supports the bottom of journal box of the axle at the time of grinding, and at the same time making it possible to use the axle as a reference point for grinding.

Wheel inner face adjusting rollers 17, 17' on part A and 18, 18' on part B are provided one being installed on both the left and right sides of both parts, and hydraulic cylinders 19, 19' are mounted on the top of the fixed frame 3 and move the said rollers forward and backward in a direction parallel to the axle.

As seen in FIGS. 2 and 3, the up and down movement of the roller supporting frames 4 is carried out by hydraulic cylinders 20, the upper ends of which are connected to two places on the bottom of the frames 4 by pin joints 21, and the lower ends of which are hingedly connected to the fixed frame 3 by pins 21'. Racks 23 and pinions 24, which engage with the racks, are provided beneath pistons 22 of the hydraulic cylinders 20, and since the axles of the pinions of the two cylinders are connected to each other by a universal coupling shaft 25, each of the pistons 22 of the two hydraulic cylinders moves up and down simultaneously at the same speed. However, the direction of the up and down movement of the roller supporting frames 4 is restrained so as to be on a circular arc of radius L, the center of which is the connecting pin 27 on the fixed frame 3 by means of hydraulic cylinder 26 having one end connected to the fixed frame 3 at the pin 27 and the end of the piston rod connected to the roller supporting frame 4 by a pin 27a, the distance between pins 27 and 27a being L. When hydraulic fluid is forced into the cylinder on both sides of a floating piston 28 in the hydraulic cylinder 26, the floating piston 28 locks the piston 29 in place. In this condition, the roller supporting frames 4 carry tion under the action of hydraulic cylinder 20, and the out up and down movement in an almost vertical direcdimension L is so pre-determined that the up and down movement of the vertical center axis of the roller supporting frames is along substantially the vertical center line of the one half of the grinding machine. However, when hydraulic oil is drawn out of the cylinder from both sides 30 of the floating piston 28, the direction of movement of the roller supporting frames 4 can swing a distance as great as the stroke 31 of the floating piston 28 since the lower end of hydraulic cylinder 20 is pinjointed so as to rotate freely.

The operation of grinding the wheels with the apparatus of the present invention which is constructed as described above, will now be explained, analyzing it step by step.

First, a railroad car is rolled into the plant and stopped at a position such that the center of the bogie is almost at the midpoint between the parts A and B of the grinding machine, i.e. the position shown by bogie 32 and wheels 33 and 33' in FIG. 2. In this condition, fixed rail 11, 11, fixed rail 45 and movable rail 34 constitute part of the maintenance shop track, and grinders 6 and wheel driving rollers 9 are held in a position below the level of the rail. The movable rail 34 is also in the longitudinal central plane taken at the center of grinding machine when it is in its forward position and in the relationship with the wheel shown in FIG. 4, and both the wheel driving rollers 9 and grinders 6 are located below the level of rail 34.

Next, as shown in FIG. 2 when the roller supporting frames 4 are lifted by hydraulic cylinder 20 and at the same time hydraulic fluid is introduced into the cylinder 26 on both sides 30 of floating piston 28 from a hydraulic pump through a control valve to produce the above mentioned locked status, the direction of movement of the roller supporting frames 4 is along a circular arc of the radius L around the center of pin 27. Therefore, the direction of upward movement of the vertical center axis of each roller supporting frame 4 is substantially along the vertical center line of each of the halves A and B of the apparatus.

Thus, even when the center of the wheel is not exactly at the center of the grinding machine, durin the process of lifting the wheels slightly off the rail as shown in FIG. 5, the horizontal component 36 of the axle weight 35 so moves the wheel that the wheel is placed and fitted between the two rollers 9, and accordingly a correct position of both the front and rear wheels is established and thus a rough adjustment in positioning the car is carried out. In this case, it is necessary that the fluid pressure in the hydraulic cylinders 20 and 26 be suflicient to withstand the horizontal component generated by the axle weight and the relationship of forces among the wheels 33, 33' and rollers 9 as shown in FIG. 7.

Thereafter, the wheel inner face adjusting rollers 17, 17 shown in FIG. 1 are moved outwardly by introducing hydraulic fluid into the roller driving cylinders 19, 19. This is done as shown in FIG. 9 by sending hydraulic fluid into cylinders 19, 19 from pumps P through control valves 37 and 38 respectively. In this case, the hydraulic pressure in the driving cylinder 19 is made somewhat higher than that in cylinder 19. When the roller 17' pushes the inner face of the wheel to a point such that the piston 39' reaches a prescribed stop position 40, the position of the inner face of one of the wheels thus established becomes a base position and the piston 39 of cylinder 19 having the lower pressure therein moves outwardly causing roller 17 to move a distance equal to the difference between the actual distance and the standard dimension between the inner faces of the two wheels. The accurate positioning of the wheels in the direction of the axle thus carried out. While this is being done, the wheel driving rollers 9 engages the flanges 43 of wheels as shown in FIG. 8, and the rollers 9 can move freely in the axial direction on roller axles 44 for a distance corresponding to gaps 46, 46' during the wheel positioning action mentioned above.

After the minute adjustment in the positions the wheels in the direction of the wheel axle is being made as explained above, the member 14 carrying movable rail 34 is moved backward until the journal box supporting block 16 is just beneath the journal box 47 of the wheel, and the wheel driving rollers 9 are rotated by activating the driving mechanism 10. The roller supporting frames 4 are lowered by means of the hydraulic cylinder 20, while the wheel is being rotated by the rotating force supplied by the rollers, so that the wheel is smoothly positioned with the bottom of its journal box 47 supported by the journal box supporting block 16, and the axle of the wheel is firmly supporting the weight of the car body.

Next, as shown in FIG. 2, the floating piston 28 in the hydraulic cylinder 26, which governs the direction of movement of roller supporting frame 4, is made free to move by pumping the hydraulic fluid out of the cylinder, and at the same time the fluid pressure on the bottom of piston 22 within hydraulic cylinder 20 is reduced to such a degree that the said pressure is suflicient to exert enough friction between driving rollers 9 and the wheels to drive the wheels against a grinding force. Then the roller supporting frames 4 are again raised so that the rollers 9 engage with the flanges 43 on the wheels. The four wheels now receive an effective driving force while the proper amount of contact pressure is always maintained for following the eccentricity and distortion of the wheels. Then, as shown in FIG. 3, the grinding wheels 6 are raised so as to grind the wheels while their position is being adjusted in the direction of the axle.

As explained above the present invention provides effective means to position the wheels and to drive the same. As to the machining member, the present invention can be used for tools other than a grinding wheel shown in the above example, for example turning tools or milling tools.

It is also possible, since the positioning of wheels is done, using an inner face of one side wheel as a basis, to measure and to remote control the dimensional deviation of the distance between the inner faces of opposing wheels through the movement of the wheel opposite the wheel used as the basis. At the same time the invention has the advantage that the positioning of the tool can be carried out automatically depending on the measured dimensional deviation mentioned above.

A detailed explanation of the feeding device for the machining member of the present machine follows.

As seen in FIGS. 10 and 11 of the drawings, a tool post 101 is mounted on a column 102 on a sliding face 103 provided on the side of the column 102 and is in contact with side guide portion 105, 105' on the front portion 104, 104'. As shown in the drawing, cutting tool posts 101 and column 102 are precisely fitted together, and holders 106, 106 hold the guide faces together.

Auxiliary column 107 is positioned on the column 102 as shown in FIG. 10, and a cross frame 108 connects the column 102 and auxiliary column 107. An auxiliary guide face 109 is provided on auxiliary column 107 opposed to the sliding surface 103. A slight gap is maintained between the guide face 109 and the face 110 of the cutting tool post 101 which contacts the guide face 109.

A pressing roller 111 of circulating roller type and a piston 112 which contacts the roller are provided in the auxiliary column 107, and are positioned in a cylinder 113 which is positioned within the auxiliary column 107. A pipe 114 is connected to the cylinder 113 and hydraulic pressure or air pressure is supplied therethrough from a pump.

A screw 115 for vertical feeding of the cutting tool post is positioned beneath the cutting tool post 111. This is driven by an appropriate power source 116, such as an electric motor or hydraulic motor, etc. through reduction gears 117, 117'.

In addition, adjacent to screw 115 is a hydraulic ram 118 contacting the underside of the cutting tool post 101 and having its lower end in a balancing cylinder 119 provided in the column 102. A pipe 120 is attached to this cylinder 119, and hydraulic pressure is supplied through the pipe 120 from a pump so that the cutting tool post 101 is urged upwardly the amount of hydraulic pressure being such that it balances the dead load of the cutting tool post, plus most of the vertical component of the cutting force. On the other hand, the hydraulic pressure which works on cylinder .113 is controlled so that it presses the cutting tool post toward the column 102, overcoming the horizontal component of the cutting force. Since the amount of force against which the screw 115 must act is reduced to a very small amount because of the pressure exerted by the balancing cylinder 119, when the cutting tool post is lifted or lowered by the feed screw 115, the pressure on the contact surface of screw is low, so that wear resistance is enhanced and a high degree of accuracy can be maintained for a long period of time. At the same time, since twisting of load is small, the rigidity of the driving portion is increased, and thus accurate cutting can be expected. It will also be effective to provide a plurality of balancing cylinders to take into account the weight distribution on each portion of the cutting tool post 101 and the direction and amount of the cutting force.

Furthermore, because the pressing cylinder 112 presses the cutting tool post 101 through the roller 111, the friction therebetween is small and because the gap between the sliding faces 109 and can be made extremely small, the raising and lowering of the cutting tool post 101 can be done accurately.

By providing a plurality of pressing cylinders 112 as shown in FIG. 11 and by selecting appropriate positions and forces thereof and considering the effect of the horizontal component of the cutting force, the moment which works on guide portions 105 and 105 can be eliminated.

The holders 106 and 106' prevent the cutting tool post 101 from inclining when the hydraulic or air pressure is lost at the pressing cylinder 112.

As explained above, the present device not only provides means for accurate cutting and grinding by accurate raising and lowering of the cutting tool post, but it also minimizes the twisting of the pressing-up screw, so that the rigidity of these driving portions is enhanced, and the contact face pressure on the screw is lower.

It is thought that the invention and its advantages will be understood from the foregoing description and it is apparent that various changes may be made in the form, construction and arrangement of the parts without departing from the spirit and scope of the invention or sacrificing its material advantages, the form hereinbefore described and illustrated in the drawings being merely a preferred embodiment thereof.

What is claimed is:

1. A grinding machine for railroad car wheels comprising a bed adapted to be fixed on a foundation, 2. fixed frame having sliding surfaces and mounted on said bed,

and roller-supporting frames movable up and down along said sliding surfaces, hydraulic cylinders connected to the supporting frames for raising and lowering them, said hydraulic cylinders having their upper ends pin connected to the bottom of the supporting frames and their lower ends pin connected to the fixed frame, said roller supporting frames being slidable on said sliding surfaces on said fixed frame for swinging movement in a direction perpendicular to the axle, frame shifting means connected to said roller supporting frames for shifting said roller supporting frames horizontally during the up and down movement of supporting frames, and a plurality of wheel driving rollers adapted to receive wheel flanges thereon and mounted on the top portion of each of said rollersupporting frames, there being a pair of rollers at positions corresponding to the ends of a railroad car lbogie axle, whereby a car can be moved up and down by the supporting frames, and the position of a vertical central axis through a respective roller supporting frame can be adjusted so that it lies substantially along a perpendicular line, and the Wheel driving rollers contact the flanges of the car wheels to impart an effective rotating force thereto.

2. A grinding machine for railroad car wheels as claimed in claim 1 in which said frame shifting means comprise further hydraulic cylinders each having one end pivotally connected to the upper end of a supporting frame at the portion thereof facing the center of the grinding machine, and the other end pivotally connected to the upper end of the fixed frame at about the center of the grinding machine, the distance between the two pins being fixed when said cylinders are filled with hydraulic fluid.

3. A grinding machine for railroad car wheels as claimed in claim 1 in which said first mentioned hydraulic cylinders connected to said roller supporting frames are coupled to each other for synchronous up and down movement.

4. A grinding machine for railroad car wheels as claimed in claim 1 further comprising wheel machining means on said bed whereby when the car is lifted up the wheels can be accurately machined by said machining means as they are rotated.

'5. A grinding machine as claimed in claim 4 further comprising a feeding device for the machining means which comprises a machining means support column having a sliding surface thereon, an auxiliary column spaced from said support column, a cutting tool post between the said support column and said auxiliary column and which moves up and down along the sliding surface of the support column, the auxiliary column having a plurality of pressure cylinders therein having rollers thereon engaging said post for pressing the cutting tool post toward the support column, and a screw threaded rod and a plurality of balancing cylinders engaging the bottom of the cutting tool post.

6. A grinding machine for railroad car wheels as claimed in claim 4 and further comprising wheel spacing adjusting means mounted between the wheel driving rollers at the top of the said fixed frames and engageable with the inner faces of the railroad car wheels to regulate the distance between inner faces of a pair of wheels at both ends of an axle, whereby at the same time the wheels are cut by the said machining means, the distance between the inner faces of the pairs of wheels at the ends of the axles are regulated by the said adjusting means.

7. A grinding machine for railroad car wheels as claimed in claim 6, wherein the wheel spacing adjusting means comprises a pair of hydraulic cylinders, and means for controlling the hydraulic pressure in one of the pair of hydraulic cylinders so that it is greater than that in the other cylinder.

8. A grinding machine for railroad car wheels as claimed in claim 6 and further comprising a wheel machining means supporting column on which said Wheel machining means is mounted and axle supporting members, cross frame on which said axle supporting members are mounted, and further columns provided on said bed spaced from both sides of said fixed frame and on which said cross frames are mounted, said axle supporting members being movable in the direction of the length of a wheel axle, whereby the grinding is done by the said machining means the ends of the axles rest on the said axle supporting members and the railway car is supported on the axles.

9. A grinding machine for railroad car wheels as claimed in claim 8 and further comprising machining means mounting members on which the wheel machining means are mounted and which are movable up and down between the columns provided on both sides of the supporting frames.

References Cited UNITED STATES PATENTS 2,622,374 12/ 1952 Stanley 5 1-1 04 2,762,171 9/1956 Schmidt 51-104 2,823,493 2/ 1958 Stanley 51-404 3,018,588 1/1962 Long 51-104 OTHELL M. SIMPSON, Primary Examiner

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US2622374 *Apr 24, 1950Dec 23, 1952Alpha Engineering & Machine WoWheel truing device
US2762171 *Apr 21, 1953Sep 11, 1956Whiting CorpApparatus for forming wheel peripheries
US2823493 *Jul 9, 1956Feb 18, 1958Standard Railway Equipment MfgWheel truing machine
US3018588 *Feb 15, 1960Jan 30, 1962Raymond A WalshWheel truing device
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3598017 *Mar 10, 1969Aug 10, 1971Stanray CorpWheel truing machine
US4276793 *Jul 5, 1979Jul 7, 1981Wirtz Arthur TMethod and apparatus for truing a metal wheel, especially of a railroad locomotive or other rolling stock
US5209021 *Aug 30, 1991May 11, 1993Amsted Industries, Inc.Apparatus and method for sprue removal and grinding of railroad wheels
US5319892 *Dec 31, 1992Jun 14, 1994Amsted Industries IncorporatedMethod for sprue removal and grinding of railroad wheels
US6062950 *Sep 16, 1998May 16, 2000Bridgestone/Firestone, Inc.Dual wheel tire grinder
WO2000015388A1 *Sep 7, 1999Mar 23, 2000Bridgestone Firestone IncDual wheel tire grinder
Classifications
U.S. Classification451/258
International ClassificationB24B5/00, B24B5/46
Cooperative ClassificationB24B5/46
European ClassificationB24B5/46