Tamper Bar For A Tamping Machine

Abstract

A two part tamper bar consisting of a tamper bar shank and a tamper bar foot removably secured to the shank. The shank is made from high carbon steel, heat treated, and the foot is made from tool steel. The foot has an integral truncated conical projection that is receivable in a conical recess in the end of the shank. Novel means removably connects the foot to the shank. The foot is rectangular in shape and has an integral semi-conical portion on one face whose greatest radius is the same as the radius of the shank end that lies adjacent to the foot and the center of the radius of the semi-conical foot portion coincides with the center of the shank end radius. The other or second face of the foot has its plane lying tangent to the circumference of the shank end and, therefore, the second face will lie flush with one portion of the shank end circumference and the semi-conical portion will lie flush with another portion of the shank end circumference.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention:

Tamper bars are used by all railroad companies for maintaining the railroad right-of-way roadbeds. A plurality of tamper bars are connected to and operated by a machine which tamps ballast between and under the railroad ties to strengthen and level the tracks or rails. Tamper bars as presently used by the railroads are a solid one piece or they are made in two pieces consisting of a shank and a foot. The foot is bolted to the shank. When the foot becomes worn through use, the tamper bar must be removed from the machine, returned to the supplier for replacement of the foot with a new foot and, finally, returned to the machine. This style of tamper bar again is costly to use due to the time it takes to remove the tamper bar shank with the worn foot from the machine and the replacement of another shank with a new foot bolted thereto.

I provide a two part tamper bar wherein a new foot can be substituted for the worn one without the necessity of removing the shank from the tamping machine. The foot is designed to protect the shank in that certain surfaces of the foot are shaped to lie flush with the adjacent surfaces on the shank. This arrangement will retard and resist any wear on the base of the shank. The semi-conical portion on the foot not only protects the shank end from wear, but it will also eliminate damage to a railroad tie should the operator of the tamping machine overshoot the distance when depressing the tamper bars as he moves from one location to another. The particular shape of the foot protects the shank and will practically eliminate the need for replacing the shank. Also, since a new foot can be substituted for a worn one without removing the shank from the machine, a tremendous saving in time for making the change results.

2. Description of the Prior Art

The patent to Heinrich Steinhage, U.S. Pat. No. 2,224,658, issued Dec. 10, 1940, discloses a shank with a bore extending inwardly from one end and receiving a rod that is integral with a foot. The foot has a wedge-shaped lower end for entering the ballast of rocks that support the railroad tracks. The top of the foot has a rectangular surface that is not with the shaped to lie flush adjacent outer surface of the lower end of the shank. No means is shown in the patent for securing the rod of the foot to the shank.

SUMMARY OF THE INVENTION

An object of my invention is to provide a two piece tamper bar in which the foot, when it becomes worn through use, can be removed from its supporting shank and a new foot substituted, this operation taking place at the machine, thus obviating the necessity of removing both shank and foot and sending them back to the shop for the substitution of a new foot and connecting it to the shank. The foot is made from tool steel which will withstand the shock and wear of the tamping operation to a greater extent than the shank which is made from high carbon steel, heat treated. Moreover, the side surfaces of the foot are shaped to lie flush with the adjacent outer surface of the shank and this will protect the shank from receiving the brunt of any blows delivered by the machine in moving the shank for driving the foot down into the ballast of the railroad bed.

A further object of my invention is to provide a two part tamper bar in which novel means is used for removably connecting the foot to the shank. This means can be operated where the machine is being used and thus permits a new tamper foot to be substituted for a worn one without the necessity of removing the tamper shank from the machine.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a side elevation of the tamper bar and shows the foot connected to the shank. Portions of the bar and foot are shown in section.

FIG. 2 is a view of the assembled tamper foot and shank when looking in the direction of the arrows 2--2 in FIG. 1.

FIG. 3 illustrates a right hand tamper foot.

FIG. 4 is an enlarged transverse section through the shank and is taken along the line 4--4 of FIG. 2.

FIG. 5 is a longitudinal section through a portion of the foot and shank on the same scale as FIG. 4 and is taken along the line 5--5 of FIG. 2. The lock screw for securing the foot to the shank is not shown in FIG. 5.

DESCRIPTION OF THE PREFERRED EMBODIMENT

In carrying out my invention I provide a shank A for a tamper bar that is adapted to be connected to a tamping machine, not shown, in the usual manner, see FIGS. 1 and 2. The shank is preferably made from high carbon steel and the lower portion of the shank has a slightly tapered cylindrical outer surface as indicated at 1. The lower end 2 of the shank A has a circular circumference and a recess 3 extends inwardly from this end and it has a conical wall 4. The axis of the recess 3 coincides with the axis of the shank.

A tamper foot, indicated generally at B in FIGS. 1, 2, 3 and 5, is preferably made of tool steel and it has a rectangularly-shaped blade 5 that has a blunt lower edge 6 designed to be forced into the gravel of a railroad ballast bed, not shown. The inner face 7 of the foot that normally is disposed near a railroad tie, not shown, when the shank and foot are being used has its lower portion bevelled at 8, see FIG. 1. The inner face 7 parallels an opposed outer face 9 and the rectangular blade 5 has an integral semi-conical portion 10 that is centered on the blade, see FIG. 2, and whose axis coincides with the axis of an integral truncated conical projection C that is designed to be removably received in the recess 3 in the shank and to be aligned with the axis of the recess.

There generally are three types of tamper bar feet. I show two of the three types in FIGS. 1, 2, 3 and 4. A center foot B is shown in FIGS. 1, 2 and 4 where the conical projection C and the semi-conical portion 10 are centered between the opposite sides 11 and 12 of the rectangular blade 5. A left hand foot B' is illustrated in FIG. 3 and here the conical projection C is disposed closer to the edge 12' than to the edge 11'. A right hand foot is not shown.

The taper on the truncated conical projection C for the foot 3 is the same as the taper of the wall 4 of the recess 3 in the shank A and the projection C is designed to seat in the recess before the end 13 of the projection reaches the inner end 14 of the recess. Also, the lower end 2 of the shank will be spaced above the upper edge 15' of the rectangular blade 5. Therefore, all of the striking force of the foot B, as it is forced into the gravel of the railroad bed, not shown, will be transmitted to the shank A through the conical surface of the projection C and the conical wall 4 of the shank recess 3. The preferred taper of the conical recess wall 4 and the conical outer surface of the projection C is preferably (0.050 inch), although I do not wish to be confined to this particular measurement.

The concial projection C for the tamper foot B is provided with an annular groove 15. The purpose of this groove will be explained when describing the operation of the device. The projection C also has a flat inclined portion 16, see FIGS. 1 and 3, against which the inner end of a lock screw 17 contacts for securing the foot B to the shank A. The lock screw 17 is received in a threaded opening 18 provided in the shank. The axis of the threaded opening 18 is perpendicular to the plane of the inclined flat portion 16 on the projection C. The lock screw 17 has a non-circular socket in its outer end for receiving a wrench, not shown, by means of which the lock screw can be screwed into locking position.

FIG. 1 further shows a pin 19 mounted in the shank A and the inner end of the pin is received in a longitudinally extending groove 20, provided in the conical projection C when the tamper foot B is connected to the shank, see also FIG. 3. The purpose of the guide pin 19 and the groove 20 is to properly align the tamper foot with the shank A so that when the shank is mounted in the tamper machine, the foot will be in the proper position.

OPERATION

From the foregoing description of the various parts of the device, the operation thereof may be readily understood. One of the features of my tamper bar shank A and the removable foot B is to shape the surfaces of the foot so that they will lie flush with the adjacent surfaces of the shank. In this way the lower end of the shank will be fully protected by the foot. Note in FIGS. 1 and 5, the upper end of the semi-conical portion 10 which is integral with the foot B, has a semi-cylindrical surface 10a whose radius is the same as that of the adjacent circular end 2 of the shank. Also, FIG. 4 shows that the face 9 of the foot B lies tangent to the adjacent circular end 2 of the shank. Therefore, the entire lower end 2 of the shank A will be protected from wear by the foot B. This feature eliminates approximately 90 percent of the wear or erosion to the lower portion 1 of the shank A, thus almost eliminating shank replacement.

The semi-conical integral portion 10 for the tamper foot B eliminates possible damage by the tamper shank or tamper foot to the railroad tie. Should the downward motion of the tamper foot strike the railroad tie, the semi-conical portion 10 will be the nearest to the tie and it will tend to deflect the foot and also the shank away from the tie rather than break or splinter the tie. The alignment pin 19 assures positive alignment of the foot B to the shank A, thus permitting the foot to be removed from the tamper shank and replaced by a new one at the tamping machine site in the field without the customary removal of the tamper bar from the machine.

The lock screw 17, see FIG. 1, serves as a positive locking action for securing the foot B to the shank A. Another feature of my invention is the annular groove 15 in the conical projection C for the foot. When the foot tapered projection C is inserted into the tapered recess 3 in the shank A, the constant tamping action will cause a "coining" action to the conical bore 4 of the recess 3 as the projection C wears into the wall 4, see FIG. 5. The annular groove 15 divides the conical wall of the projection C into two bearing surfaces 21 and 22, one on each side of the groove. These two surfaces 21 and 22 on the projection C tend to "coin" the mating surface portions on the conical wall 4 of the recess 3, and the portion of the conical wall that is disposed opposite to the annular groove 15 will not be "coined" and, therefore, will remain of the same diameter thus creating an annular inwardly extending rib 23 which will extend into the groove and tend to lock or secure the two mating sections together, i.e., the conical projection C and the recess 3. An epoxy resin, not shown, may be used on the lock screw 17 to insure that it will remain tight and not loosen due to vibrations in the operation of the tamping machine.

Claims

I claim:

1. A tamper bar comprising:

a. a vertical shank having a recess extending inwardly from its lower end, the recess having a conical wall; and

b. a foot having a conical projection extending above an upper edge of said foot and adapted to be removably receivable in said recess, the size of the conical wall of the projection and the size of the conical wall of said recess being such as to prevent the inner end of the conical projection from contacting with the inner end of said recess, said conical projection also spacing the upper edge of said foot below the adjacent end of said shank when said conical projection is snugly received in said conical recess;

c. said foot having a lower blunt edge with the inner and outer surfaces of said foot extending between said upper and lower edges, the portions of these inner and outer surfaces of the foot that lie adjacent to said shank being shaped so as to lie flush with the adjacent surface portions of said shank.

2. The combination as set forth in claim 1: and in which

a. the conical projection on said foot having a flat inclined portion; and

b. a lock screw removably mounted in a threaded opening whose axis is perpendicular to the plane of said flat inclined portion;

c. whereby said lock screw can be screwed into said threaded opening for contacting with said flat inclined portion for holding said conical projection of said foot from accidental removal from said shank recess.

3. The combination as set forth in claim 1: and in which

a. said conical projection of said foot having an annular groove spaced from the end of said projection;

b. whereby said groove is designed to receive any annular rib-like projection formed by the "coining" action created by the successive strokes by said shank delivered to said foot through the conical wall of said shank recess contacting with the adjacent conical surfaces of said projection disposed on both sides of said annular groove, the annular rib-like projection thus formed tending to hold said conical projection in said shank recess.

4. The combination as set forth in claim 1: and in which

a. the outer surfaces of said foot that lie adjacent to said shank are stream-lined with the adjacent outer surface of said shank include the outer surface of a blade-shaped portion of said foot whose plane is tangent to the circumference of the circular end of said shank, the opposite parallel surface of said blade-shaped portion having an integral semi-conical portion whose greatest radius equals the radius of the shank circular end, the axis of said semi-conical portion coinciding with the axis of said conical projection of said foot and also coinciding with the axis of said shank recess.

5. A tamper foot comprising:

a. a blade-like portion having parallel outer and inner surfaces and upper and lower edges;

b. said inner surface having an integral semi-conical portion whose apex lies in the plane of said inner surface and whose upper end lies flush with the upper edge of said blade-like portion; and

c. an integral conical projection extending upwardly from the upper edge of said blade-like portion and from the upper end of said integral semi-conical portion.

6. The combination as set forth in claim 5: and in which

a. the inner surface of said blade-like portion being bevelled toward said outer surface from a point coinciding with the apex of said integral semi-conical portion and extending to the lower edge of said blade-like portion.