The illustrative embodiments may best be described by reference to the accompanying drawings where:
All figures are drawn for ease of explanation of the basic teachings of the present invention only; the extensions of the figures with respect to number, position, relationship, and dimensions of the parts to form the preferred embodiment will be explained or will be within the skill of the art after the following description has been read and understood. Further, the exact dimensions and dimensional proportions to conform to specific force, weight, strength, and similar requirements will likewise be within the skill of the art after the following description has been read and understood.
Where used in the various figures of the drawings, the same numerals designate the same or similar parts. Furthermore, when the terms “top”, “bottom”, “upper”, “lower”, “first”, “second”, “width”, “length”, “spacing”, “channel”, “groove”, “end”, “side”, “horizontal”, “vertical”, and similar terms are used herein, it should be understood that these terms have reference only to the structure shown in the drawings as it would appear to a person viewing the drawings and are utilized only to facilitate describing the illustrative embodiment.
A latch assembly for a safety rail system according to the preferred teachings of the present invention is shown in the drawings and generally designated 100. In particular, safety rail system 10 can be of a variety of forms including railings which are secured to a horizontal supporting surface. In the preferred form shown, safety rail system 10 is removably placed and/or relatively movable on the horizontal supporting surface. In most preferred forms, safety rail system 10 includes mounting plates 102 having relatively large masses such as cast or otherwise fabricated bases of the types shown in U.S. Pat. Nos. 3,020,023; 3,776,521; 4,787,603; 5,816,554; or 6,554,257. Thus, in such applications, it is generally desired to utilize safety rail system 10 for temporary purposes. However, in other applications, mounting plates 102 could be permanently secured to or relative to the horizontal supporting surface. Likewise, the railings can be removably mounted to the mounting plates 102 such as by being slidably received in post receptors 30 formed on mounting plate 102 shown or can be permanently secured to the mounting plates 102.
According to the preferred teachings of the present invention, safety rail system 10 includes a gate 106 including two spaced fixed members 108 and 110. In a preferred form, fixed members 108 and 110 are respectively in the form of a pivot post and a latch post shown as being slidably received in receptors 30 of different mounting plates 102. In the preferred form, fixed members 108 and 110 are cylindrical, in the most preferred form tubular, and are shown as having circular cross sections.
Gate 106 further includes a panel 112 moveable relative to fixed member 110 between an open position allowing access between fixed member 110 and panel 112 to allow passage and a closed position preventing access between fixed member 110 and panel 112 to prevent passage. It is noted that panel 112 and fixed member 110 have a spacing therebetween when panel 112 is in the closed position. In the most preferred form shown, panel 112 has a first side pivotably mounted to fixed member 108 such as by a pair of hinges 114 vertically spaced and extending between panel 112 and fixed member 108 for pivotably mounting panel 112 about a pivot axis extending parallel to but spaced from fixed member 108. Hinges 114 can be of any desired form as conventional including but not limited to of a commercially available type.
Gate 106 in the form shown includes a support wheel 116 suitably secured to a second side of panel 112 opposite to hinges 114. The purpose of support wheel 116 is to reduce the torque stress placed upon hinges 114. Thus, support wheel 116, if desired and provided, can be of any desired form as conventional including but not limited to of a commercially available type.
Panel 112 according to the teachings of the present invention can be of a variety of forms and types which functions to prevent access between fixed members 108 and 110 when in a latched condition. In the form shown, panel 112 includes a vertical hinge column or post 118 defining the first side of panel 112 and a vertical latch column or post 120 defining the second side of panel 112. Posts 118 and 120 are held in a spaced parallel relation such as by a plurality of horizontal bars 122 extending therebetween. It should be appreciated that bars 122 can be suitably secured with posts 118 and 120 such as by being integrally formed therewith such as by bending, by welding, or the like. Bars 122 can have a fixed length or can have an adjustable length such as being telescopic. Panel 112 can also include suitable enclosure provisions such as netting, sheeting, or the like extending between posts 118 and 120 and bars 122.
According to the preferred teachings of the present invention, latch assembly 100 includes an elongated catch 130 to slidably receive fixed member 110. Catch 130 is movably mounted to latch post 120 between a latched position and an unlatched position according to the preferred teachings of the present invention. Catch 130 is in the spacing between panel 112 and fixed member 110 when catch 130 is in the unlatched position. In the most preferred form, catch 130 is in the form of a channel having U-shaped cross sections. In particular, catch 130 includes first and second latch plates 132 held in a spaced parallel relation by an interconnecting abutment plate 134, with a groove being defined between plates 132. Each latch plate 132 includes a width extending in a direction parallel to the spacing between panel 112 and fixed member 110. Specifically, in the preferred form, the widths of plates 132 each are of a size to be received in the spacing between panel 112 and fixed member 110 in the closed position and in the preferred form considerably smaller than the spacing, particularly, in the order of less than 50% of the spacing and in the most preferred form less than 30% of the spacing. However, the width of plates 132 are of a size to present a substantial overlap with panel 112 and in the preferred form shown greater than a diameter of fixed member 110.
Each latch plate 132 further includes an extended length extending in a direction perpendicular to the spacing between panel 112 and fixed member 110 and multiple times greater than the width. Specifically, in the preferred form, the extended length is at least three times greater than the width and, in the most preferred form shown, is in the order of four times the width. Each plate 132 includes upper and lower ends extending along the width and defining the length therebetween. The upper and lower ends of plates 132 each include an outwardly extending flange 136 extending generally perpendicular to plates 132 and 134 along the width and perpendicular to the length. An aperture 138 is formed in plate 134 intermediate plates 132. The groove between plates 132 is generally equal to but slightly greater than the diameter of and for slideable receipt on post 110.
In the form shown, a linkage 140 includes first and second arms 142 held in a spaced parallel relation by spindles 144 extending generally perpendicular therebetween. Arms 142 and spindles 144 are suitably removably secured together such as by bolts 145 extending through arms 142 and spindles 144. Spindles 144 are spaced inwardly from the opposite ends of arms 142. The outer ends of first and second arms 142 are pivotally mounted to first and second latch plates 132, respectively, about a catch pivot axis extending approximately midway between the free edges of plates 132 and abutment plate 134 or of the width of plates 132 and at about one fourth of the length from the outwardly extending flanges 136 of the upper end towards the outwardly extending flanges 136 of the lower end. Arms 142 are pivotably mounted by any suitable manner that does not detrimentally protrude between plates 132 such as by hinge clip pins 146 extending through plates 132 and arms 142.
Arms 142 are further pivotably mounted to latch post 120 of gate 106 about a latch pivot axis spaced from and parallel to the catch pivot axis defined by pivot pins 146. In the most preferred form, spindle 144 opposite to catch 130 is rotatably received (and/or arms 142 are pivotable relative to spindle 144) in a passage formed in latch post 120 and defines the latch pivot axis. In the most preferred form, the ends of arms 142 opposite to catch 130 extend beyond post 120.
In the most preferred form, latch assembly 100 includes provisions to prevent arms 142 from pivoting at an obtuse angle downwardly relative to post 120. In the preferred form, an abutment 148 extending horizontally and generally perpendicular to post 120 against which the top surface of the free ends of arms 142 abut to prevent pivotal movement therebeyond.
In the preferred form shown, abutment 148 includes a downwardly extending U-shaped lip 150. In the most preferred form, apertures 152 are formed in the free ends of arms 142 outwardly of column 120. Corresponding apertures 154 are formed in lip 150. Thus, latch assembly 100 can be locked in a latched position by a latch member such as by a rod extending through all of apertures 152 and 154, by a padlock extending through aperture 152 in one of arms 142 and aperture 154 in one side of lip 150 or the like.
Now that the basic construction of latch assembly 100 according to the preferred teachings of the present invention has been set forth, a method of operation can be explained, and some of the advantages obtained thereby highlighted. In particular, for the sake of explanation, it will be assumed that gate 106 is open or in other words extends at an angle to a plane defined by fixed members 108 and 110 and that latch assembly 100 is not being engaged. Due to the mass of catch 130, arms 142 will pivot about the latch pivot axis with the outer ends of arms 142 moving downwardly until the inner ends of arms 142 abut with abutment 148 as shown in
When it is desired to latch gate 106, a user pivots linkage 140 relative to latch post 120 from the position shown in
With gate 106 in the plane of fixed members 108 and 110, the upward force upon latch assembly 100 can be released such that linkage 140 pivots relative to latch post 120 from the unlatched position shown in
In the latched position shown in
If desired, latch assembly 100 according to the teachings of the present invention can be prevented from being moved from the position shown in
It can be appreciated that the linkage 140 can be pivotally mounted to fixed member 110 instead of post 120 of panel 112. In this case, the catch 130 is releasably engaged with the post 120 of panel 112, and abutment 148 is provided on fixed member 110. Detailed arrangement of the corresponding elements and operation of the linkage 140 and the catch 130 according to the teachings of the present invention would be within the skill of the art.
Latch assembly 100 according to the teachings of the present invention includes relatively fewer moveable components that can be easily fabricated and assembled at low cost. Furthermore, operation of latch assembly 100 according to the teachings of the present invention is easy and reliable. Furthermore, latch assembly 100 according to the teachings of the present invention can be used with commercially available safety rail systems with or without minor modification of these commercially available safety rail systems.
Thus since the invention disclosed herein may be embodied in other specific forms without departing from the spirit or general characteristics thereof, some of which forms have been indicated, the embodiments described herein are to be considered in all respects illustrative and not restrictive. The scope of the invention is to be indicated by the appended claims, rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are intended to be embraced therein.
The present application claims the benefit of U.S. Provisional Appln. No. 60/812,728 filed on Jun. 12, 2006.
Number | Date | Country | |
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60812728 | Jun 2006 | US |