US3099333A

US3099333A - Step structure

Info

Publication number: US3099333A
Application number: US215046A
Authority: US
Inventors: Peter R Hollaender
Original assignee: Individual
Current assignee: Individual
Priority date: 1962-08-06
Filing date: 1962-08-06
Publication date: 1963-07-30
Anticipated expiration: 1980-07-30

Description

July 30, 196 P. R. HOLLAENDER 3,099,333

STEP STRUCTURE Filed Aug. 6, 1962 2 Sheets-Sheet 1 Iii]. I? M I I 2 f I /z /6 HI lim o z INVENTOR.

BY M WWW y 1953 i P. R. HOLLAENDER 3,099,333

STEP STRUCTURE Filed Aug. 6, 1962 2 Sheets-Sheet 2 IN VENTOR United States Patent 3,099,333 STEP STRUCTURE Peter R. Hollaender, 22% Raeburn Drive, Cincinnati 23, Ohio Filed Aug. 6, 1962, Ser- No. 215,046 3 Ulaims. (Cl. 132--90) This invention relates to steps of the type used in manholes, brlck or concrete walls, chimneys and similar structures. These steps are U-shaped and the ends of the arms are configurated to provide anchors which are embedded in a wall structure, for example, leaving the cross bar exposed. In the prior art, these steps, for the most part, have been made of cast iron or steel. One serious fault with these steps is that they rust in damp locations, in manholes in particular, and they eventually become unsafe and have to be replaced. Despite replacement costs these steps have been universally accepted because of their low initial cost.

It is recognized that certain aluminum alloys are better materials than cast iron or steel for many purposes, because they do not deteriorate appreciably. However, to substitute these alloys for the cast iron or steel in the step constructions of the prior art would make the initial cost prohibitive for most installations.

The primary objective of the present invention has been to provide a step made of such alloys that can be sold at a price competitive with the steps of the prior art.

The typical step of the past has been cast as an integral unit. Using a sand mold of the size to be handled readily, two steps could be cast at a time in one flask. This was done by forming the cavities such that the open sides of the U configurations faced one another with the leg sections of one straddling a leg section of the other. In the usual foundry one man could turn out approximately 200 steps per day. Using the same size flask one man can turn out approximately 400 steps per day of the type of this invention. In other words, the step of this invention doubles the productive capacity of a man and, as a result, production costs are cut to a point where they offset the diiference in cost between steel and aluminum.

To fulfill the primary objective of the invention, I have broken each step into three parts, two arms and :a cross bar, .and have provided a unique, exceedingly strong means for rapidly assembling them at the job site. Broken down in this way, the pieces making up four complete steps may be cast simultaneously in a flask of the same size capable of turning out only two of the integral steps of the prior art. Additional savings are afforded in shipping charges, because the steps are lighter in weight than those of the past, and they may be shipped in smaller cartons than those required in the past.

Other objectives and advantages of the invention will be readily apparent to those skilled in the art from the following detailed descriptions of the drawings in which:

FIGURE 1 is :a diagrammatic representation of the drag part of a flask showing the way in which two steps of the prior art are arranged for casting.

FIGURE 2 is a diagrammatic representation of the drag part of a flask showing how the parts of four steps of this invention may be arranged for casting.

FIGURE 3 is a perspective view showing a step of this invention in assembled condition.

FIGURE 4 is a front elevational view of the step of FIGURE 3 with parts broken away for illustration purposes.

FIGURE 5 is a fragmentary perspective view showing the forward end only of a leg section and one end only of the cross bar section of the step in the process of assembly. In this view the parts are shown inverted.

Referring now to FIGURE 1, a drag section of a flask is shown diagrammatically at 10. Two manhole steps Patented July 30, 1963 of the prior art are indicated generally at 1111. Each step consists of two arms 12-1'2, which are arranged in spaced parallel relationship and which are joined by an integral cross bar. In order to provide anchorage for the step in a brick or concrete wall, the ends of the arms are turned up as shown at 1414. Due to the integral nature of the steps only two may be cast at a time in a flask of the size shown in FIGURE 1.

Referring now to FIGURE 2 the drag section 10 of a flask which is identical in size to the one shown in FIG- URE 1 is illustrated, but in this instance, the parts of four steps made in accordance with the principles of this invention are illustrated. Each step is broken down into a cross bar 15 and a pair of arms 1616. These individual components may be arranged in different ways within the drag. As shown, four cross bars 15 .are disposed side-by-side going cross-wise of the drag and seven arms are shown side-by-side extending lengthwise of the drag with the eighth arm being placed across the ends of the four cross bars.

Reference is now made to FIGURE 3 which shows an assembled step of this invention. The cross bar, which constitutes the tread part of the step, may have the upper surface thereof grooved, as shown at 17, to provide an antiskid surface. The two ends of the cross bar are turned up as 'at 1818 to provide flanges which prevent a persons foot from slipping off the ends of the step. The underside of each of the ends of the cross bar is configurated to provide .a saddle 19 consisting of two side walls, the inner one being designated 29 and an outer one designated 21. As shown, the outer wall 21 is a continuation of the turned up end 18 on top of the cross bar. The saddle defines a U-shaped channel 22 which opens at the underside of the bar and which is rectangular in transverse section. As shown in FIGURE 4, the tread part of the cross bar may be thinned down between the ends, leaving front and rear flanges depending from the forward and rear edges thereof.

The arms 15-46 of each step are identical. In each instance, the inner end of a arm has a flattened knob 23 cast as an integral part thereof, the knob serving as an .anchor when the step is embedded in a wall. In this instance, the knob extends both above and below the arm. Obviously, other configurations may be given the inner end of the arm including one in which the arm turns up only and one in which the arm turns down only. As best shown in FIGURE 5, the forward end of each arm is configurated to provide a seat 24 defined by a pair of flanges, designated 25 at the outer end, and designated 26 spaced inwardly from the outer end, which flanges extend all of the way around the periphery of the arm. These two flanges 25- and 26 are spaced apart a distance equal to the width of .a saddle part of the cross bar. The seat areas of the arms are rectangular in transverse section as shown.

The component parts of the step are assembled at the construction site utilizing set screws such as the one shown .at '27 in FIGURE 5. For this purpose the outer wall 21 at each end of the cross bar is drilled and tapped. Preferably, the outer face of each seat 24 has an indentation 28 therein which receives the inner end of the set screw 27. As shown, the set screw is that type having a hexagonal cavity 29 at its outer end designed to receive an Allen head wrench (not shown). It may be seen therefore, that the saddles of the cross bar are adapted to receive the seats of the arms in slip fit relation and the set screws then tightened against the indentation 28. This securely locks the .arms to the cross bar. In order to finish off the assembly two aluminum plugs such as the one shown at 30 in FIGURE 5 may be driven into the treaded bore to cover the outer end of said screw.

The preferred alloy utilized in the casting of the step of this invention is set forth in ASTM Spec. GM70B and Federal Spec. QQA 601B, Class 26. This alloy is highly corrosion resistant and exceedingly strong. If desired those portions of the arms which are to be embedded within a wall may be coated to further increase the corrosion resistance of the metal. This coating is shown by the stippling in FIGURE 3 and preferably it extends out to a point 31 on each of the arms. This brings the coating well out from the surface of a wall to which the step is attached.

In the claims the step of this invention is designated a manhole step. This designation is not intended as a limitation upon the use of the step.

Having described my invention, I claim:

1. A manhole step comprising a pair of cast aluminum arms and a cast aluminum cross bar, said arms being identical and each being configurated at the inner end thereof to provide a Wall anchor, a seat portion at the outer end of each arm defined by spaced peripheral flanges, said seat portion being rectangular in transverse section, a saddle at the underside of each of the ends of said cross bar, said saddle defining a downwardly opening channel which is rectangular in transverse section and of a size to receive a seat portion of an arm in slip fit relation, there being a bore drilled and tapped through the outer side of each of said saddles, and .a set screw engageable in each of said bores to lock said saddles in said seats.

2. A three part manhole step comprising a pair of identical, cast aluminum arms and a cast aluminum cross bar, each of said arms configurated at the inner end thereof to provide a Wall anchor, a seat at the outer end of each arm that is rectangular in transverse section, a saddle at the underside of each end of said cross bar defining a downwardly opening channel which is rectangular in transverse section and of a size to receive a seat of an arm in slip fit relation, there being a bore drilled and tapped through the outer side of each saddle, and a set screw engageable in each of said bores to lock said saddles to said seats.

3. A three part manhole step as set forth in claim 2 in which the wall of the saddle that is drilled and tapped is substantially thicker than said set screw is long whereby the set screw is recessed in said bore, and a plug of .aluminum of a size to fill the outer portion of said bore.

References Cited in the file of this patent UNITED STATES PATENTS 845,803 Manross Mar. 5, 1907 1,588,566 Wismer June 15, 1926 1,855,442 Cunningham Apr. 26, 1932 2,215,129 Morris Sept. 17, 1940

Claims

1. A MANHOLE STEP COMPRISING A PAIR OF CAST ALUMINUM ARMS AND A CAST ALUMINUM CROSS BAR, SAID ARMS BEING IDENTICAL AND EACH BEING CONFIGURATED AT THE INNER END THEREOF TO PROVIDE A WALL ANCHOR, A SEAT PORTION AT THE OUTER END OF EACH ARM DEFINED BY SPACED PERIPHERAL FLANGES, SAID SEAT PORTION BEING RECTANGULAR IN TRANSVERSE SECTION, A SADDLE AT THE UNDERSIDE OF EACH OF THE ENDS OF SAID CROSS BAR, SAID SADDLE DEFINING A DOWNWARDLY OPENING CHANNEL WHICH IS RECTANGULAR IN TRANSVERSE SECTION AND OF A SIZE TO RECEIVE A SEAT PORTION OF AN ARM IN SLIP FIT RELATION, THERE BEING A BORE DRILLED AND TAPPED THROUGH THE OUTER SIDE OF EACH OF SAID SADDLES, AND A SET SCREW ENGAGEABLE IN EACH OF SAID BORES TO LOCK SAID SADDLES IN SAID SEATS.