US2948914A

US2948914A - Caster for a mechanic's creeper or the like

Info

Publication number: US2948914A
Application number: US594760A
Authority: US
Inventors: Jr Glenn Ludgate Fitkin
Original assignee: Individual
Current assignee: Individual
Priority date: 1956-06-29
Filing date: 1956-06-29
Publication date: 1960-08-16
Anticipated expiration: 1977-08-16

Description

1960 G. L. FlTKlN, JR 2,948,914

CASTER FOR A MECHANIC'S CREEPER OR THE LIKE Filed June 29, 1956 INVENTOR. 32 GLENN L. FIT/(Ml, (/12.

Y F167 B CASTER FOR A MECHANICS CREEPER OR THE LIKE Glenn Ludgate Fitkin, In, 3045 Hopewell Place, Toledo, Ohio Filed June 29, 19 56, Ser. No. 594,760

2 Claims. (Cl. 16- 45) This invention pertains to caster devices and more particularly to a caster for a mechanics creeper.

Such casters are normally made from castings because their particular shape does not readily permit other methods of production. However, these castings require of cast ones. This gives a finished creeper that is easier to handle and considerably cheaper to ship.

It is an object of my invention to provide an improved caster for utilization with mechanics creepers.

It is another object of my invention to provide a less expensive caster.

It is a third object of my invention to provide a caster whose dimensions and concentricity are more precisely maintained.

Still another object of my invention is to create a caster that is more durable and more attractive in appearance than conventional ones.

A further object of my invention is to produce a lighter weight caster.

For further consideration of what is novel and my invention, refer to the remainder of the specification, the following claims, and the accompanying drawing.

In the drawing:

Figure 1 is a perspective view of apparatus embodying my invention,

Figure 2 is an elevational view of a portion of the apparatus of Figure 1,

Figure 3 is a detailed, cross-sectional view of a portion of the apparatus of Figure 2,

Figure 4 is a cross-sectional view of a portion of the apparatus of Figure 3,

Figure 5 is a detailed, cross-sectional view of a portion of the apparatus of Figure 3,

Figure 6 is a detailed, cross-sectional view of alternate apparatus of that shown in Figure 3, and

Figure 7 is a detailed, cross-sectional view of another form of the apparatus of Figure 3.

Referring to the drawing, and more particularly to Figure 1, a creeper 10 consists of a platform 11 and casters 12. Four casters are provided at the corners of the creeper 11 although six are sometimes used with the additional two placed in the center of the longitudinal edges=for additional strength. Each comprises a revoluble member 16 and a tortuous rod 13, attached to the underside of creeper 11 by means of a tube 14 afiixed atent Exact concentricity is assured in q 'lce 2 to plate 15 which is screwed or otherwise appended to creeper 11.

Member 16 comprises a disc 17 and a tube 18. Disc '17, of circular cross-section, has rounded edge portions 21 and an essentially flat central portion 19. The mem ber 16 is designed to contact the floor surface on rounded portion 21 with the plane of rotation of the member being at an angle of approximately 45 to the surface. The rod 13 is of a well known shape that permits member 16 to contact the surface at a point in a vertical plane that extends through the axis of tube 14 and which also contains the line of direction of travel of the member. The point of contact is also substantially displaced from a vertical line through the axis of tube 14.

An annular wall 20 is provided in the center of disc 17 and the entire disc and annular wall may be stamped in finished form in one operation.

The annular wall 20 is sized to closely fit within the inner diameter of tube 18 so that the latter may be easily concentrically located with respect to disc 17. The annular wall also provides a greater surface area on which tube 18 may be attached to disc 17. This is preferably accomplished by brazing which produces a clean, strong weld. The disc -17 and tube 18 are properly positioned and placed in a cont-rolled, non-oxidizing atmosphere furnace. A piece of brazing metal, of appropriate size, is placed on the annular wall within tube 18. The furnace is then brought to proper temperature and the metal melts, forming a strong bond between the wheel member and the lower end of the tube. The operation may be carried out equally effectively in a continuous furnace. The controlled atmosphere maintains the caster in a bright condition that eliminates the usual requisite cleaning operation.

Tube 18 is sized by an upsetting operation to control the inner diameter at portion 22 adjacent disc 17 to assure proper fit with the annular wall. This also provides additional brazing area and additional strength for the member 16. The upsetting assures that the edge of end portion 22 will be in a plane perpendicular to the axis of the tube and thus assures that the axis of the tube will be perpendicular to the rotational plane of disc 17. The opposite end of tube 18 contains a chamfer 23 which facilitates the entry of end 24 of rod 13 which is held in tube 18 by means of a split ring 25 located in groove 26. This arrangement holds the shaft securely in tube 18 but allows for rotation of the tube and disc on the shaft. An additional groove may be placed on the inner diameter of tube 18 if desired. Rod 13 is positioned in the tube so that its end 24 contacts raised portion 34 of at the center of the annular wall 20 which results in minimum of area in contact and a minimum of friction.

Tube 18 is preferably made with a slot 27 extending longitudinally throughout its length. The slot is less then ten thousandths of an inch in width but need not be uniform. This slot is partially filled by capillary action with part of brazing metal 28 during the brazing operatron; however, a groove 29 remains at the inner surface of tube 18 to provide an access from the top of the tube for lubrication of the entire portion of rod 13 located Within the tube.

An alternate form of member 16 is shown in Figure 6 with a recessed annular wall 30 formed in a member 16. Tube 31 in this case is sized, but not necessarily by means of an upsetting operation, to assure that the outer diameter thereof will be less than that of the recess with a clearance of no more than .00 being preferred. The tube is then .afiixed to the member by brazing according to the aforementioned operation. This design gives similar advantages to the form shown in Figure 3 3 and has a larger area of contact between the tube and disc for a given size tube.

In Figure 7, annular Walls 32 are formed in member 16". Here tube 33 must be subjected to a sizing operation that will maintain both its inner and outer diameters within specified limits. The two pieces are similarly brazed with an additional area of contact between them which is greater than that of Figure 6 by the depth of the recess multiplied by its inner periphery and is greater than that of Figure 3 by the depth multiplied by the outer periphery.

Member 16" has a central portion extending inwardly to form a shallow cone. This particular shape is somewhat stronger since the central portion is closer to being perpendicular to the surface on which the member rides. More important, however, is the fact that the rounded portion of the member which contacts the surface must be displaced considerably inwardly from the outer diameter of the member. If the member contacted the surface at, or adjacent to, the outer diameter, bending or chipping of the disc would be likely to occur.

The term annular wall as used herein, unless other- Wise qualified, includes any wall, either projected or recessed, that is centrally located at least on the side of the disc to which the tube is afiixed.

It may be seen that my invention provides a creeper caster that is less expensive, more durable, lighter in weight, more attractive, and more precisely made than conventional casters. It comprises a disc made of a single plate of circular shape and having rounded edges adapted to ride on a surface.

An annular wall is provided in the center of the disc to produce a means for locating a tube on the concave side of it and to afford a greater area for brazing the tube to the disc. The end portion of the tube adjacent the disc is sized and may also be upset to increase the thickness of the tube so that its strength is increased and a larger diameter is created for brazing. A slot is preferably made in the tube extending through its thickness and longitudinally over its length. This slot is partially filled during the brazing operation in whidh the tube is joined to the disc but leaves a groove on the inner surface or the tube to permit lubrication.

The description contained herein is the best known of carrying out my invention and is intended to be in a descriptive and not a limiting sense. The scope of my invention is limited only by the depending claims.

What =1 desire to obtain by Letters Patent is contained in the following claims.

I claim:

1. A caster for a mechanics creeper comprising: a stamped circular disc having a rounded edge portion near the outer periphery which is adapted to contact the surface on which the creeper rides at an angle of approximately 45, said disc having an integral, annular wall concentrically located at the central portion thereof, at least on the side of said disc toward which the edge portion is rounded; a tube permanently, concentrically attached to the same side of said disc, said tube having a diameter approximately the same as the diameter of said annular wall to fit therewith and be concentrically located with respect to said disc, the longitudinal axis of said tube being perpendicular to the plane of rotation of said disc, said tube forming a closed end, cylindrical recess with said disc, and said tube having a slot in a wall thereof extending throughout its length; brazing metal dis-posed between said tube and said annular wall and in said slot but leaving a groove at least on the inner surface of said tube; a rod having one end extending into said tube in closely fitting relationship and the other end of said rod being adapted to be attached to the underside of said creeper; and means for holding said rod in rotatable but non-slidable relationship with respect to said tube.

2. A caster for a mechanics creeper comprising: a stamped circular disc having a rounded edge portion near the outer periphery which is adapted to contact the surface on which the creeper rides at an angle, said disc having an integral, annular wall concentrically located at the central portion thereof, at least on the side of said disc toward which the edge portion is rounded, said annular wall extending substantially perpendicularly to the surface of said side; a tube permanently, concentrically attached to the same side of said disc, said tube having a thicker wall at one end thereof to provide a greater surface with which said tube can be joined to said disc, said tube otherwise having substantially constant inner and outer diameters, one of which is approximately the same as the diameter of said annular wall to fit therewith and be concentrically located with respect to said disc, the longitudinal axis of said tube being perpendicular to the plane of rotation of said disc, and said tube forming a closed end, cylindrical recess with said disc; joining metal located between the thicker end of said tube and said annular wall to permanently join said tube and said disc; a rod having one end extending into said tube in closely fitting relationship and the other end of said rod being adapted to be attached to the underside of said creeper; and means for holding said rod in rotatable but non-slidable relationship with respect to said tube.

References Cited in the file of this patent UNITED STATES PATENTS 386,082 Newhall July 10, 1888 1,085,090 Lachman Ian. 20, 1914 1,210,311 Higinbotham Dec. 26, *1916 1,259,269 Murray Mar. 12, 1918 1,268,980 Krurnholz June 11, 1918 1,292,812 Lachman Jan. 28, 1919 1,471,134 Ash Oct. 16, 1923 2,279,831 Lempert et a1 Apr. 14, 1942 2,332,089 Knight Oct. 19, 1943 2,589,847 Noelting et al. Mar. 18, 1952 2,714,809 Voss Aug. 9, 1955 FOREIGN PATENTS 278,881 Switzerland Nov. 15, -1