US 3659678 A
A portable floor anchor which is designed for use in automobile body repair shops. The anchor can be moved about a garage floor on retractable wheels to a job where it is to be used. When the wheels are retracted, a special seal is brought into contact with the floor to create a vacuum chamber. This chamber is evacuated to hold the anchor in place by differential air pressure. A clevis, a pivoted pulling post or other pulling or attaching means are mounted on the anchor.
Description (OCR text may contain errors)
United States Patent Hall, Jr.
m1 3,659,678 May 2,1972
 PORTABLE FLOOR ANCHOR  inventor: Bertie Forrest Hall, Jr., Berkley, Mich. [731 Assignee: Raymond P. Wolgast, Clawson, Mich.
[221 Filed: Nov. 4, 1970 ] Appl. No.: 86,776
521 user. ..1aa/s, |so/ns 511 men. ..B60tlll4  FleldolSearch ..l80/il5,l25;188/5  References Cited UNITED STATES PATENTS 3,116,897 1/1964 Theedm'. "1 88/5 X FOREIGN PATENTS OR APPLICATIONS 1,159,866 2/1958 France.. 1 88/5 Primary Examiner Duane A. Reger Attorney-Hamess, Dickey 8: Pierce  ABSTRACT A portable floor anchor which is designed for use in automobile' body repair shops. The anchor can be moved about a garage floor on retractable wheels to a job where it is to be used. When the wheels are retracted, a special seal isbrought into contact with the floor to create a vacuum chamber. This chamber is evacuated to hold the anchor in place by differential air pressure. A cievis, a pivoted pulling post or other pulling or attaching means are mounted on the anchor.
7 Claims, 5 Drawing Figures PATENTEDNAY 21912 I 3.659.678
' \N INVENTOR.
SUMMARY OF THE INVENTION The use of vacuum operated floor anchors is a relatively new development in the automobile body repair field. According to this new technology a large vacuum pad or the like is provided with a depending annular seal which makes contact with the floor. The seal defines a vacuum chamber which'is evacuated by a vacuum pump to hold the anchor securely in place. The anchor may be used as a hold down device or as a mounting pad for a pivoting pulling port or the like.
Several problems have been encountered with the use of such vacuum pads. Garage floors are frequently rough and portions of the concrete may be chipped away. When the anchor is positioned on such a floor area leakage of air past the seal can pose a threat to the proper functioning of the unit. Furthermore, the anchor pad itself is relatively heavy and is subjected to rugged use. The seal supports the weight of the anchor as well as the force created by the vacuum. Accordingly, the seal must be able to withstand substantial forces applied thereto as well as some abrasion. Accordingly, it is an object of the present invention to provide a rugged, yet inexpensive portable floor anchor which is able to provide an effective seal on relatively rough surfaces and which has a durable and long wearing seal.
DESCRIPTION OF THE DRAWING FIG. I is a perspective view of a floor anchor constructed in accordance with the present invention, the anchor being illustrated in a typical usage;
FIG. 2 is a bottom plan view of the floor anchor of FIG. 1;
FIG. 3 is an enlarged sectional view with parts broken away of the structure illustrated in FIGS. 1. and 2, taken along the line 3-3 of FIG. 2; and
FIGS. 4 and 5 are sectional views similar to FIG. 3 but with the seal being deformed under varying loads.
DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 1 illustrates an anchor constructed in accordance with the present invention and shown in use as a tie down device for straightening an automobile frame 12. The anchor 10 has a clevis 14 through which a chain 16 passes. The chain 16 is shown extending around a portion of the frame 12 to hold such frame portion down when another portion of the frame is subjected to an upward force by a jack (not shown) or the like. The use of the anchor 10 illustrated in FIG. 1 constitutes only one of various uses to which the anchor may be put. It is to be understood that the invention is not limited to any particular use, but may be employed to advantage in performing a variety of jobs.
The anchor 10 includes a flat metal plate 18 having a plurality of upstanding radial ribs 20. The plate 18 is of circular shape and possesses flat upper and lower surfaces 22 and 24 respectively. Vulcanized to the bottom surfaces 24 about the peripheral margin thereof is a neoprene seal 26. The seal 26 is designed to rest on a garage floor 28 and thereby define a vacuum chamber 30. The chamber 30 comprises the space bounded by the seal 26 and located between the lower plate surface 24 and the floor 28. Air is evacuated from the vacuum chamber 30 through a vacuum port 32 which is connected to a Venturi type suction pump 34. The suction pump 34 is operated by compressed air received from a flexible hose 36.
The anchor 10 is designed to be moved about the floor 28 on three wheels 38 which are carried by toggle clamp I third annular lip 46. The three lips 42, 44 and 46 are concentric, with the first lip 42 being disposed in the radially outermost position. The lip 42 will be seen to be inclined radially outwardly and includes a frusto-conical outer surface 48 and a 5 frusto-conical inner surface 50. Both the surfaces 48 and 50 are radially outwardly and downwardly inclined in converging relationship due to the greater angle of taper of the surface 50. The lip 42 terminates in an annular crest or edge 52 which engagesthe floor 28. The lip 44 has an outer frusto-conical wall 54 and an inner frusto-conical wall 56 which converge downwardly toward one another to meet at a crest or lower edge 58. The outer wall 54 is downwardly and radially inwardly inclined while the inner wall 56 is downwardly and radially outwardly inclined. Spaced radially inwardly of the lip 44 is the lip 46, which is provided with an inner frusto-conical surface 60 and an outer frusto-conical surface 62 both of which are downwardly and radially outwardly inclined. The surfaces 60 and 62 converge toward and blend at a crest or lower edge 64. The crest 64 is disposed in a horizontal plane which is beneath the horizontal plane of the crest 58 but is substantially above the horizontal plane of the crest 52.
FIG. 3 depicts the as molded," unstressed shape 'of the seal 26. FIG. 4 shows the position which the seal 26 assumes when it supports the weight of the plate 18 and the structure mounted thereon, but without the chamber 30 being evacuated. FIG. 5 shows the fully deformed position of the seal 26 when air is evacuated from the chamber 30. From these views it will be apparent that the lip 42 is the first portion of the seal 26 to engage the floor when the wheels 38 are retracted. It will be seen that as the loading on the pad is progressively increased the seal 26 is distorted radially outwardly to bring a greater portion of the surface 50 into contact with the floor 28. Eventually, the lip 46 is brought into contact with the floor mechanisms 40 mounted on the upper surface 22 of the plate 18. The toggle clamps 40 may be actuated to retract and lower the wheels 38. When the wheels 38 are lowered the seal 26 is raised off the floor 28. When the wheels 38 are retracted the seal 26 is brought into engagement with the floor 28 and supports the weight of the anchor 10 thereon.
The present invention is distinguished by the construction of the seal 26. The seal 26 has a triple lip construction incorporating a first annular lip 42, a second annular lip 44 and a and as air is evacuated from the vacuum chamber 30 the radially inner surface 60 of the lip 46 is brought into contact with the floor. The deflection of the lip 46 is also limited by its engagement with the surface 56 of the central lip 44. The lips 42 and 46 are readily deflectable in order to provide substantial area contact of the seal 26 with the floor 28. On the other hand, the central lip 44 is not readily deflectable and serves as a shoulder to limit the overall deformation or compression of the seal. The lip 44 provides the seal with desirable structural strength and prevents over-deflection of the seal, while the lips 42 and 46 provide extended area contact with the floor 28 to prevent air leakage despite irregularities or roughness of the floor.
The seal 26 is desirably constructed of neoprene having a 35 to 40 durometer rating. One representative embodiment of the invention utilizes a plate 18 having a diameter of 30 inches. This anchor pad provides a vacuum chamber covering a floor area of approximately 720 square inches. The vacuum which is drawn in the chamber 30 is equal to approximately 27 inches of mercury. The overall loading on the anchor pad is, therefore, approximately 9,400 pounds. It will thus be apparent that a substantial force is applied to the seal 26 which places great demands on the seal. The configuration of the seal 26 has been found to provide an ideal combination of durability and high sealing effectiveness.
What is claimed is:
1. A floor anchor pad including a rigid base member, a floor engaging annular resilient seal secured to a lower surface of said base member, said base member being operable to close the space bounded by said seal at the upper end thereof, said base member having an opening through which air is evacuated from said space, said seal having a plurality of concentric depending annular lips, a first one of said lips being downwardly and radially outwardly inclined and being relatively readily compressible under loading to bring a progressively greater surface area thereof into engagement with the I floor and a second one of said lips having its lower end spaced 2. The structure set forth in claim 1 including a third lip disposed radially inwardly of said second lip and said first lip being disposed radially outwardly of said second lip.
3. The structure set forth in claim 1 in which said first lip has converging radially inner and outer side walls each of which is inclined downwardly and radially outwardly, said radially inner side wall having a greater angle of taper than the radially outer side wall.
4. The structure set forth in claim 2 in which said second lip has radially inner and outer side walls which are inclined convergingly downwardly and in which said radially outer side wall is inclined radially downwardly and inwardly and in which said radially inner side wall is inclined downwardly and radially outwardly.
5. The structure set forth in claim 2 in which said third lip is inclined radially outwardly and has a radially outer side wall engageable with the radially inner side wall of said second lip.
6. The structure set forth in claim 2 in which the lower edge of said third lip is disposed in a horizontal plane located between the horizontal planes of the lower edges of said first and second lips.
7. The structure set forth in claim 1 in which said seal is made of a neoprene material having a durometer rating of between 35 and 40.
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