US2522821A - Ladder bracket for scaffolds - Google Patents

Description

Sept. 19, 1950 c. F. HANSEN LADDER BRACKET FOR SCAFFOLDS Filed Nov. 12, 1946 2 Sheets-$heet l FIG.2

FIG.4

iNVENTOR CHARLES F. HANSEN ATTORNEY Sept. 19, 1950 c. F. HANSEN LADDER BRACKET FOR SCAFFOLDS 2 Sheets-Sheet 2 Filed Nov. 12, 1946 INVENTOR CHARLES F. HANSEN Patented Sept. 19, 1950 UNITED STATES PATENT OFFICE LADDER BRACKET FOR SCAFFOLDS Charles F. Hansen, Chicago, 111. Application November 12, 1946, Serial No. 709,188

5 Claims. 1

The present invention pertains to scaffold supports and more particularly to improvements in ladder jacks.

The primary object of the invention is to provide a scaffold support that is safe and reliable.

Another object is to provide a ladder jack having instrumentalities which preclude the possibility of becoming accidentally detached.

A further object of the invention is to provide a scaffold support of the ladder jack variety wherein a locking device is embodied which facilitates ready adjustment and assures the maintenance of such adjustment and thereby insures safety.

The invention features a lockin device comprising a spring biased locking element which cooperates with a bayonet type slot to render a ladder jack readily detachable and demountable and still insure safety and security in its attached or mounted position.

A further feature of the invention resides in the flexibility of the scaffold support or ladder jack by giving to said support a four-point suspension on the ladder siderails, as well as a twopoint suspension on the ladder rungs. The ladder jack according to the present invention is extensible and adjustable, within a predetermined range, to fit a ladder of any width and distance between rungs. Moreover, the strain and tension is taken up at a plurality of points and the risk of injury is reduced to a minimum. The scaffold support of the present invention will fit in any space between standards or side rails on a regular extension ladder. Also, the scaffold support can be used either as a bracket or as a hanger on outside or underside, respectively, of ladder.

Other objects and features of the invention will appear from the following description when taken in conjunction with the accompanying drawings, wherein,

Fig. 1 is a side elevation, partly in section, of the scaffold support or ladder jack according to the present invention;

Fig. 2 is a detail view of the pivotal connection of the arms of the ladder jack;

Fig. 3 is a perspective view of the spring-biased locking element of the invention in its operative position;

Fig. 4 is a top view of the locking element shown in Fig. 3;

Fig. 5 is a perspective view of the ladder jack arrangement of the invention mounted on a ladder in operative position;

Figs. 6, 7, and '8 are detail views of the upper anchor or suspension members, and

Figs. 9, 10, and 11 are detail views of the lower anchor or suspension members.

Having reference to Figs. 1 to 5 of the drawings wherein like reference characters indicate the same parts throughout the several views, a ladder H comprising side rails l2 and I3 and rungs l4 and I5, is illustrated in an inclined position in the manner of resting against a wall (not shown). Supported on the rungs Hi and i5 and braced by the standards or rails 12 and it is the ladder jack or scaiiold support accordin to the invention. a

The ladder jack, indicated generally as [6,. comprises a horizontal member I? adapted to be pivotally connected at I 8 to a notched member or adjustor l9. Although the member H is shown in Fig. 1 as fashioned with an upwardly directed curved portion adapted to fit into the space provided by the member l9 and its reverted end 2! and pivotally constrained by rivet it, every equivalent form of pivotal connection is, of course, contemplated.

Bar 19 is provided along its upper edge with a plurality of bayonet type slots 22 which are adapted to coact with a hasp-like member 23. Member 23 is provided with a pair of trunion supports 24 preferably integrally formed on said member 23. Trunnions 24 are adapted to be rotatably supported in a pair of brackets or clamps 25 secured to an upper anchor member, indicated generally as 26.

The member I? has secured thereto by rivets 27 a trunnion portion 28 which is provided integrally therewith with a pair of trunnions 22 adapted to be rotatably supported by a pair of clamps 3| secured to a lower anchor member, indicated generally as 32. It is, of course, understood that the bar I! and portion 28 may be made of one piece, such that the trunnions 22 are formed integral with the bar ll. Moreover, it is contemplated that the means of pivotally supporting the scaffold supporting members 23 and 28 to the anchor members 26 and 32 may take other well known forms.

Member 231s provided with an elongated slot 33 of sufiicient length 34 to freely admit the full width of bar l9. Interposed between the lower edge of bar l9 and the adjacent face of portion 23 is a locking element 35 pivotally mounted on portion 23 by means of a shouldered rivet 36 to permit free rotation of said locking element. Encircling the shoulder of rivet 36 and disposed between the locking element 3.5 and portion 23 is a coiled spring 3! one end of which grips or embraces the edge of portion 23 and the other end similarly embraces the proximate edge of locking element 35 whereby element 35 is normally biased in a counterclockwise direction, as viewed in Fig. 4, against a stop 31 fastened to member 23.

Looking element 35 is provided with a vertically directed flange 38 adapted to be locked under predetermined operating conditions, between stop 31 and bar I9. Instead of the stop 31, the locking element 35 may be provided with a depending flange 39 adapted to overhang and engage the member 23.

The upper anchor member 26 is shown in detail in Figs. 6, 7, and 8, and comprises a sheath 4| adapted to encase or surround a pair of extensible members 42 and 43 which are slidably retained in sheath 4| by bolts 44 and slots 45. The sheath 4| terminates along one of its bottom edges in conformations 46, 41, and 48. Conformations 46 and 48 encase the outside of the ladder I'llIlg I4 while the conformation engages the inside of rung I4. With this arrangement of conformations, the conformations 46 and 48 serve to sustain part of the load imposed on the scaffold plank while the conformation 4'! acts together with conformations 46 and 48 to retain the anchor member 26 upon the rung I4 against accidental displacement. The extensible members 42 and 43 are conformed with ends 52 adapted to wrap partly around the standards I2 and I3 of the ladder II to sustain the load imposed on scaffold 5|.

The lower anchor member 32, shown in Figs. 9, 10, and 11 comprises a sheath |4| adapted to slidably accommodate extensible members I42 and I43 which are constrained to predetermined endwise movement by slots I45 and bolts I44. Sheath |4| is provided with conformations I46, I ll, and I48 adapted to cooperate with rung 5 of ladder II so that the load on scaffold 5| is imparted through bar or member I! to conformations I46 and I48. Conformation I41 acts to-- gether with conformation I46 and I48 to retain the anchor member 32 upon the rung I5 against accidental displacement.

The clamps 25 and 3| have not been shown in Figs. 6 to 11 because it is contemplated that the form of retainers and bearings for the trunnions 24 and 29 may be varied to include all equivalent forms. The member I9 may be made considerably longer and may contain a greater number of slots 22 to enhance its adjustment possibilities. Moreover, the clamps 25 may be so designed as to support the trunnions 24 closer to the upper edge of the anchor member 26 so that the member l9 may readily extend over the top edge of the anchor member. If this is not desired then the anchor member may be notched or slotted to permit passage of the member or bar I9 therethrough.

In the operation of the scaffold support according to the present invention, the anchor members 26 and 32 are placed upon the rungs I4 and I5, respectively, with the extensible members 42, 43, I42, and I43 properly adjusted to the width of the ladder and the conformations 52 and I52 embracing the standards I2 and I3. The locking element 35 is swung to the position indicated 35" in Fig. 4, and the bar I9 is threaded through slot 33 to determine which notch 22 is to be engaged by members 23 so as to hold member IT in a horizontal position which will properly support the scaffold planks 5|. After this has been determined, the members l1, l9, and 23 are swung to the dotted positions l1, l9, and

23' shown in Fig. 1, whereat the flange 38 of looking element 35 will clear the bottom edge of member I9 and will be biased by spring 37 to the position against stop 3?. With the element 35 in this position the bar I9 is locked against withdrawal because the restricted opening 55 of slot 33 is less than the width of the member I9. Now, when the ladder jack I6 is lowered to the solid line position shown in Fig. 1, the member I9 is locked against withdrawal, as shown in Fig. 3, and may be released only upon assumption of the abnormal position indicated by the dotted lines in Fig. 1 and manually swinging the looking element 35 to the dotted position 35" indicated in Fig. l.

In prior devices of the type herein shown there are not found the safety features of the (present invention which overcome the dangers encountered by workers of the trade, and which dangers are recognized by framers of municipal and state codes for the safety and security of trade workers. With prior structures one may butt his shoulder against the lower member of the scaffold ack and pivot the scaffold jack upwardly to cause collapse and dislodgement of the scaffold, which eventuality is not possible with the structure according to the present invention.

Although the present invention has been described in connection with a specific embodiment thereof it is understood that all modifications are contemplated which come Within the range and scope of the appended claims.

What is claimed is:

1. In a ladder bracket, a scaffold supporting member, anchoring means having rail straddling and rung straddling instrumentalities comprising facilities for pivotally supporting said member, suspension means pivotally articulated to said member and comprising a hasp element and an adjustor, said adjustor provided with notches cooperable with said hasp element, other anchoring means having rail straddling and rung straddling instrumentalities comprising facilities for pivotally supporting said hasp element, said hasp element provided with a slot adapted to freely receive said adjuster, and spring-loaded locking means pivotally carried on said hasp element effective cooperable with said notches under certain predetermined conditions to restrict said slot, whereby said hasp element and said adgustor are interlocked.

2. In a ladder bracket, a scaffold supporting member, anchoring means having rail straddling and rung straddling instrumentalities and comprising facilities for pivotally supporting said member, suspension means pivotally articulated to said member and comprising a first element having slot facilities and a second element having notch facilities, other anchoring means having rail straddling and rung straddling instrumentalities comprising facilities for pivotally supporting said first element, locking means pivotally carried on said first element and effective under certain predetermined operating conditions for restricting said slot facilities for interlocking said first element and said second element, and means associated with said locking means to prevent release of said locking means under said operating conditions.

3. In a ladder bracket, a scaffold supporting member, anchoring means having rail straddling and rung straddling instrumentalities comprising facilities for pivotally supporting said member, means pivotally articulated to said member and comprising a hasp element and an adjustor, said adjustor threadable through a slot in said hasp element and provided with notches cooperable with said hasp element, other anchoring means having rail straddling and rung straddling instrumentalities comprising facilities for pivotally supporting said hasp element, a slot restricting instrumentality pivotally mounted on said hasp portion, said slot restricting instrumentality adapted to partially cover said slotted opening in said hasp to prevent, within predetermined limits, detachment of said hasp portion and said adjustor, a stop on said hasp element for limiting rotation of said instrumentality, and a flange integral with said instrumentality intenposable between said stop and said adjustor for locking said instrumentality against rotation within said predetermined limits.

4. In a ladder bracket, a scaffold supporting member, anchoring means comprising facilities for pivotally supporting said member, means pivotally articulated to said member and comprising a hasp element and an adjustor, said adjustor threadable through a slotted opening in said hasp element and provided with notches cooperable with said hasp element, other anchoring means comprising facilities for pivotally supporting said hasp element, and an instrumentality pivotally mounted on said hasp element and adapted to partially cover said slotted opening in said hasp, whereby said hasp element when resting in one of said notches is prevented, under certain operating conditions, from becoming detached from said adjustor.

5. In a ladder bracket, a scaffold supporting member, anchoring means comprising facilities for pivotally supporting said member, means pivotally articulated to said member and comprising a hasp element and an adjustor, said adjustor threadable through a slot in said hasp element and provided with notches cooperable with said hasp element, other anchoring means comprising facilities for pivotally supporting said hasp element, a slot restricting instrumentality REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 767,768 Sackman Aug. 16, 1904 1,143,678 Winans June 22, 1915 1,441,847 Goodwin Jan. 9, 1923 1,477,738 White Dec. 18, 1923 1,906,275 Kramer May 2, 1933 FOREIGN PATENTS Number Country Date 303,250 Great Britain Jan. 3, 1929

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