US3217431A - Shoes for snowplows and the like - Google Patents

Description

Nov. 16, 1965 w HEINZRQTH ETAL 3,217,431

SHOES FOR SNOWPLOWS AND THE LIKE Filed March 21, 1963 INVENTORS. EMIL J. HANK J Merl 6. Sceales 3/ AT'IoRNEY United States Patent Ofl Fice 3,217,431 Patented Nov. 16, 1965 3,217,431 SHOES FOR SNOWPLOWS AND THE LIKE William H. Heinzroth, Canton, and Emil J. Hank, Minerva, Ohio, assignors to Good Roads Machinery Corporation, Minerva, Ohio, a corporation of Ohio Filed Mar. 21, 1963, Ser. No. 266,878 1 Claim. (Cl. 3742) This invention relates to shoes for supporting snowplows, graders, spreaders, and like devices a predetermined distance from the surface on which they are operating to decrease wear on the surface engaging parts of such devices.

In general, the invention is directed to a ground level flotation shoe assembly which resiliently supports a blade member, such as a moldboard of a snowplow, above the surface being operated upon. The shoes of such assemblies which slide over the supporting surface regulate the height of the blade or scraper from the ground, and under the present invention, each shoe assembly is of such a construction that the hinge line of rotation of the shoe is at or may be below the ground or surface level. The weight of the assembly is carried on bearing means located within the housing of each sliding shoe and a pin which secures each shoe to its respective shoe housing comes into play only when the entire shoe assembly is at a position Where the shoe is free of the ground or operating surface. In previous constructions, the pin in service carried the entire weight of the shoe assembly :and the blade with which it was employed.

By locating the hinge line or pivot axis of the shoe at or below ground level, the effective moment around the hinge line is less than the case where the hinge line is above the ground level so that the construction of the invention results in more uniform wear on shoes and consequent longer life.

Other objects and advantages of the invention will appear in the courses of the following description.

The drawing furnished herewith illustrates the best modes presently contemplated for carrying out the invention as hereinafter set forth.

In the drawing:

FIGURE 1 is a perspective view showing the shoe assembly of the invention secured to a snowplow;

FIG. 2 is a side elevational view of the shoe assembly shown secured to part of a snow-plow assembly with parts broken away and sectioned;

FIG. 3 is a side elevational view looking at the right side of FIG. 2 and with parts omitted;

FIG. 4 is a side elevational view showing the shoe pivoted in one direction due to the irregularities of the surface over which the shoe is operating; and

FIG. 5 is a view similar to FIG. 4 and showing the shoe pivoted in the opposite direction.

The drawing, for the purposes of illustrating the use of the shoe assembly of the invention, shows a moldboard or blade 1 of a snowplow. A semi-circular frame 2 is suitably secured to the rear of moldboard 1, and such frame is pivotally secured to the frame 3.which in turn is pivotally connected to the frame 4 on the prime mover 5. Thus, the semi-circular frame 2 and moldboard 1 may be moved together in a horizontal plane to horizontally locate the moldboard 1 in a number of different positions relative to its vertical axis. Means are employed to secure frame 2 to frame 3 when the moldboard is in the position desired but need not be described as it has no bearing on this invention.

A trip spring assembly 6 is connected between the frame 2 and the moldboard 1 to permit the moldboard to override obstructions in the path of travel with a spring, not shown, inside the trip spring cylinder efiecting return of the blade to normal service operation.

In order to lift the moldboard 1 and the accompanying parts so that the assembly may be transported free of a traveled surface, a hydraulic cylinder 7 is provided. The lower end of cylinder 7 is connected to a pair of plates 8 which are secured to the frame 4 on the prime mover and the upper end of the cylinder 7 is connected to the triangular shaped plates 9 which are pivoted to the upper ends of the vertical posts 10, the lower ends of such posts being secured to the frame 4. The outer ends of triangular plates 9 are connected to the frame 2 by the chain 11 so that when cylinder 7 is activated from the prime mover 5 through hydraulic lines, not shown, the plates 9 are pivoted rearwardly on posts 16 and lift the moldboard 1 and the assembled parts from the ground or other surface on which the unit is operating.

The moldboard 1 is normally provided at its leading edge with a replaceable cutting blade 12 and in most uses of the snowplow it is desirable to raise the cutting blade 12 from the surface or ground being operated on so that the weight of the plow assembly is not carried by the cutting blade with a consequent decrease in the useful life of cutting blade 12. This is accomplished by providing casters, or shoes behind the moldboard 1 on which the Weight of the assembly is taken and which provide a clearance between moldboard 1 and its cutting blade 12 and the ground surface.

In the illustration of the shoe assembly of the invention in the drawing, there is shown a resilient and adjustable connection of the shoe assembly to the snowplow unit previously described. Such assembly comprises, in general, a shoe housing formed of the stem 13 and the foot portion 14, a shoe 15 disposed below the foot portion 14, and connected thereto by pin 16, and a housing 17 to receive'the stem 13 of the shoe housing.

The housing 17 is generally cylindrical and is secured to the vertically spaced plate members 18 through which housing 17 vertically extends. The plate members 18 are secured to the semi-circular frame 2 and form a part thereof. The top of housing 17 is closed by the cap nut 19 which is rigidly secured within housing 17. The lower end of the housing 17 is open to slidably receive the stem 13 of the shoe housing.

Stem 13 and foot portion 14 of the shoe housing are hollow and may be cast or of welded construction. Stem 13 is divided generally centrally by partition 20 which has a central opening therethrough.

A bolt 21 extends upwardly through a vertical opening in partition 20 and through a complementary vertical opening provided centrally in cap nut 19. The opening in partition 20 is of a smooth bore while the opening in cap nut 19 is threaded. Bolt 21 at the neck portion is unthreaded but is threaded at the upper end complementary to the threads in cap nut 19. The threaded section of bolt 21 extends upwardly from partition 20 a substantial distance and the head 22 of bolt 21 abuts the bottom surface of partition 20.

In order to accomplish resilient support of the shoe housing and vertical adjustment thereof, the inside of the stem 13 of the shoe housing is provided with a coil spring 23 assembled around bolt 21 and which is confined between the partition 20 and the ball bearing unit 24 assembled around bolt 21 above coil spring 23. The ball bearing unit 24 is held in its predetermined position by the castellated nut 25 which is threaded onto bolt 21 above bearing unit 24. The nut 25 is fixed in the desired position by cotter pin 26. The assembly described permits the stem 13 to rotate within housing 17 with the coil spring 23 rotating on the ball bearing unit 24. The position of the stem 13 and the foot portion 14 of the shoe housing with respect to housing 17 is regulated by rotating bolt 21 to the desired. position by means of handle 27.

The hollow foot portion 14 of the shoe housing is provided at the upper end with the circular flange 28 which may abut the lower end of housing 17. In order to provide bearing surfaces for the shoe 15, the bearing blocks or inserts 29 extend horizontally within the respective ends of the foot portion 14. The shoe is received within the foot portion 14 of the shoe housing and the upper surface 30 of shoe 15 rests against the bearing blocks 29 in service and slides over such blocks.

The shoe 15 is of a solid construction and in order to provide for ready movement of shoe 15 on bearing blocks 29 the upper surface 30 of the shoe is of a semicircular shape, and the bearing blocks 29 are formed with their bearing surfaces complementary to the upper surface 30 of the shoe 15.

The lower portion 31 of shoe 15 is of a generally rectangular shape and is flat on the bottom to readily slide over a surface. The outer ends 32 of the shoe 15 extend upwardly angularly outwardly to give the shoe the general appearance and action of a sled runner and thereby provide for more efiicient movement of the shoe 15 over the surfaces on which it is operating.

In order to provide a loose connection between the foot portion 14 of the shoe housing and the shoe 15, and yet permit relative movement between shoe 15 and pin 16, the shoe 15 generally centrally thereof and adjacent the upper edge, has an elongated slot 33 which is disposed in alignment with an aperture 34 extending horizontally through the foot portion 14 of the shoe housing.

The elongated extent of slot 33 lies generally in a plane corresponding to the semi-circular plane in which the surface 30 of shoe 15 extends. The walls of the foot portion 14 are enlarged downwardly below aperture 34 as at 35 to reinforce the aperture.

Pin 16 extends through slot 33 and aperture 34 with the head of the pin abutting against one wall of the foot portion 14 and the fastening means 36 for securing the pin 16 in place abutting the opposite wall.

Pin 16 is disposed loosely within slot 33 with a clearance thus being provided between pin 16 and slot 33 in the shoe 15, as shown in an exaggerated manner in FIG. 2 of the drawing. The clearance described positively insures that the Weight of the supported snowplow does not bear on the pin 16, but rather, in service only bears directly on the shoe 15. Thus, the only function of pin 16 is to hold the shoe 15 and foot portion 14 of the shoe housing together when the entire shoe assembly is free of the ground or other operating surface.

FIGS. 4 and 5 illustrate the action of the shoe 15 when passing over an uneven surface 37 tending to tilt the shoe. Thus, in FIG. 5, the shoe 15 has tilted upwardly at the forward end. However, the shoe cannot turn over because it is of a sufficient width, as shown in FIG. 3, to engage the walls of the foot portion 14, as shown in FIG. 5 of the shoe housing. been tilted in the opposite direction.

The hinge line, or pivot axis 38 of rotation of shoe 15, is located at or below the ground or surface level in that shoe 15 rotates on the axis 38 which is described by the center of the circle of which bearing inserts 29 are a part. As the diameter of the circle of which bearing In FIG. 4, the shoe 15 has 4 inserts 29 are a part is increased beyond that shown in FIG. 2, the hinge line or pivot axis 38 of shoe 15 will move below the ground level. Thus, when the shoe, for example, as in FIG. 4, engages an uneven surface, the low hinge line prevents the shoe from tending to tilt or tip over with consequent decrease of wear on the engaging end of the shoe. Instead, the shoe, due to the decrease of the effective moment around the hinge line tends to level off and move downwardly toward the obstruction with a consequent pivoting of the shoe and movement of the slot therein forwardly with respect to the pin 16. An opposite action is reflected in the shoe in FIG. 5 where an uneven surface is being passed over by the rear portion of the shoe.

Various modes of carrying out the invention are contemplated as being within the scope of the following claim particularly pointing out and distinctly claiming the subject matter which is regarded as the invention.

I claim:

A flotation shoe assembly having a housing adapted to be secured to portable apparatus and support said apparatus on a surface with the hinge line of the assembly being at or below ground level which comprises:

(a) a solid sliding shoe having a generally flat bottom merging into upwardly inclined end portions with a semi-circular upper surface and having a single generally centrally located elongate-d slot in the upper portion thereof extending in a plane complementary to the upper surface of the shoe,

(b) a shoe housing having a cylindrical stem projecting centrally upwardly therefrom into said housing and secured thereto and a foot portion with the foot portion having an aperture extending therein in line with the slot in said shoe,

to) circumferentially spaced bearing inserts provided within the bottom side of the foot portion to receive the shoe and support the shoe housing directly on the shoe, with the bottom surface of the bearing inserts being of a shape conforming to the upper surface of the shoe so that the shoe is adapted to move freely over said bearing inserts, and

(d) a pin extending through the aperture in the foot portion of the shoe housing and said pin having a diameter less than the width of the slot such that the pin extends loosely through the slot in the upper portion of the shoe to hold the shoe and shoe housing together when the shoe assembly is raised from the supporting surface and without affecting the bearing of the shoe housing directly on said shoe when the shoe is in service on the supporting surface.

References Cited by the Examiner UNITED STATES PATENTS 435,666 9/1890 Rempio 280-26 572,847 12/1896 Wesle 28026 727,472 5/1903 Snell 280-26 933,510 9/1909 Wesle 28026 2,460,348 2/1949 Henry 37148 X 2,778,126 1/ 1957 Shannon 37-42 BENJAMIN HERSH, Primary Examiner.

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