US2289499A

US2289499A - Adjustable ladder equalizer

Info

Publication number: US2289499A
Application number: US388880A
Authority: US
Inventors: Harry F Husted
Original assignee: HAR JO IND RES CORP
Current assignee: HAR JO IND RES CORP; HAR-JO INDUSTRIAL RESEARCH Corp
Priority date: 1941-04-16
Filing date: 1941-04-16
Publication date: 1942-07-14
Anticipated expiration: 1959-07-14

Description

July 14, 1942. H, F, HUsTEb 2,289,499

USTABL'JE LADDER EQUALIZER Filed April 16, 1941 3 Sheets-Sheet l T5 HFHua y 1942. H. F. HUSTED I 2,289,499

ADJUSTABLE LADDER EQUALIZER Filed April 16, 1941 3 Sheets-Sheet 2 I N o .EHusZea? f lt 49 I /IIIIIIIIII July 14, 1942. H. F. HUSTED 2,289,499

- v ADJUS-TABLE LADDER EQUALIZER I Filed April 16 1941 SSheets-Sheet 3 Patented July 14, 1942 ADJUSTABLE LADDER EQUALIZER Harry F. Husted, Shavertown, Pa., assignor to Har-Jo Industrial Research Corporation, Newark, N. J.

Application April 16, 1941, Serial No. 388,880

9 Claims.

This invention relates to an equalizer for ladders and is an improvement over the construction embodied in my prior Patent No. 1,542,775 which issued June 16, 1925.

An object of this invention is to provide as an attachment for ladders an equalizing means for engagement with the lower portion of a ladder in order to provide a means whereby the lower end of the ladder may be engaged with uneven ground with the ladder in a vertical position and the supporting means at the bottom of the ladder firmly contacted with the uneven ground.

Another object of this invention is to provide an equalizing structure of this kind which includes a means for automatically locking the equalizing structure in adjusted position.

A further object of this invention is to provide an equalizing structure of this kind including a pair of supporting members which are secured one to each side of the ladder and are connected together'so that movement of one of the supporting members will effect movement of the other supporting membenin the opposite direction.

A further object of this invention is to provide individual locking means for the two equalizing members and a flexible connection between the locking structure whereby both locking members may be released at one time in order to permit the equalizing members to be shifted relative to the side rails of the ladder.

A further object of this invention is to provide in an attachment of this kind an improved means for correlation with the locking structure in order to firmly lock the adjustable supporting members relative to the ladder.

A further object of this invention is to provide an improved base or foot for each supporting member, which is so constructed that it may be disposed at right angles to the supporting members or may be disposed in substantially parallel relation to the supporting members.

A further object of this invention is to provide in a foot or base structure for an attachment of this kind an improved gripping device, which is so constructed that when one portion thereof is worn the device may be adjusted to bring another portion thereof into operation and thus make it unnecessary to entirely replace the gripping element.

A further object of this invention is to provide a ladder equalizing means which is so constructed that it may be mounted on different types of ladders, and which may be adjusted to a particular ladder so that the upper portion of the equalizing means will not form an obstruction which might catch on a foot of the user, the upper portion of the equalizing means being positionable beneath a ladder rung and the rung protecting the equalizing means against contact with a foot.

To the foregoing objects and to others which may hereinafter appear, the invention consists of the novel construction, combination and arrangement of parts as will be more specifically referred to and illustrated in the accompanying drawings, wherein is shown an embodiment of the invention, but it is to be understood that changes, variations and modifications may be resorted to which fall within the scope of the invention as claimed.

In the drawings:

Figure 1 is a detail front elevation of an equalizing structure constructed according to an embodiment of this invention, which is mounted on the lower end of a ladder, the ladder being shown in fragmentary form,

Figure 2 is a sectional view taken on the line 2-2 of Figure 1,

Figure 3 is a sectional view taken on the line 33 of Figure 2,

Figure 4 is a sectional view 44 of Figure 1,

Figure 5 is a sectional view taken on the line 55 of Figure 2,

Figure 6 is a sectional view taken on the line 6-6 of Figure 2,

Figure '7 is a fragmentary side elevation of one of the equalizing members with the foot portion thereof in substantially vertical position,

Figure 8 is a fragmentary vertical section of the clamping means for the foot,

Figure 9 is a sectional view taken on the line 99 of Figure 1,

Figure 10 is a vertical section taken through the lower portion of a ladder having a modified form of equalizing structure mounted thereon,

Figure 11 is a fragmentary front elevation of the structure shown in Figure 10,

Figure 12 is a sectional view taken on the line I2-I2 Figure 11, and

Figure 13 is a fragmentary sectional view taken on the line l3-l3 Figure 10.

Referring to the drawings, numeral I0 designates generally a ladder structure including side rails II and I2 and rungs I3. An equalizing structure is mounted on the lower ends'of the rails II and I2 and includes a pair of equalizing members, generally designated as I4 and I5. The two equalizing members I4 and I5 are of like construction and the description of one of these taken on the line devices will apply equally as well to the description of the other device.

The equalizing device I4 includes a substantially tubular guide member I6, which is formed at the lower end thereof with a right angularly disposed flange II engageable beneath the lower end of the rail I I. The guide I6 is provided with a cut-out I3 and the outer wall I9 of the guide I6 is formed with an opening 26 through which an attaching bolt 2| is adapted to engage. The head 22 of the bolt 2| is adapted to be countersunk in a recess 23, which is formed in the outer wall I 9. The guide member I3 also includes a vertically disposed flange 24 engageable on the rear side of the rail II, which is adapted to be secured by means of a bolt 25 or the like engaging through the flange 24 and the rail I.

An elongated slide member 26 is movable lengthwise of the guide member I6 and "is rectangular in transverse section. The slide member |'6 is adapted to be locked in vertically adjustedposition with respect to the guide I6 by means of a threaded locking shaft 21, which is threaded through a boss 28 carried by the. guide l6. The inner end of the shaft 2! is adapted to contact with the confronting face of the slide member 26, so as to bind slide member26 in the guide I6. In order to provide a means whereby the binding action of the slide 26 with respect to the guide I6 ma be facilitated, I have provided an elongated flat strip 29 which is provided with outwardly bent upper and

lower end portions

36 and 3| respectively. The flat strip 29 is in the form of a liner which may be of substantially soft metal, such as copper or the like, which will frictionally engage the confronting face of the slide '26 and will hold the slide 26 against movement relative to the guide I6 as the slide I6 is locked by means of the threaded shaft 2!.

The shaft 21 at its outer end has secured thereto a right angularly disposed lever or arm 32 which may be fixed to the shaft 21 by means of a set screw 33 or other suitable fastening means. The shaft 2'! is adapted to be normally urged to a slide locking position by means of a substantially heavy coil spring 34, which engages about the boss 28 and has one end thereof anchored, as at '35, to a lug 36 carried b the guide I6. The other end of the spring 34 is adapted to engage a lug 3'I which is carried by the arm 32.

An elongated flat bowed resilient strip 33 is connected at one end, as at 39, to the guide member I6 enga ing in a recess 46 formed in the rear wall I9 of the guide I6. The opposite end of the flat resilient strip 38 is adapted to be secured to the equalizing member I at the opposite side of the ladder. The upper end portion of the strip 38 is formed on an arc, as at 4|, and constitutes a guide for a flat resilient tie member 42. The tie member 42 is secured, as at 43, to the upper end of the slide member 26 and the opposite end of the strip 42 is secured as at 44 to the upper end of the slide member 45. The tie member 42 provides a means whereby when one of the slide members is moved upwardly with respect to its associated rail the other of the slide members will be moved downwardly in the same proportion. The bowed guide member 4| has secured thereto aplurality of clips or'reverted guide members 46, which engage at least partly about the under side of the tie strip 42 so as to constantly hold the strip 42 with the outer face thereof contacting with the under face of the resilient guide strip 4|,

The equalizing member I5 is constructed similar to the equalizing member I4 with the exception that the locking shaft I'Ia, which has secured tlrereto a shaft operating arm 32a, has the threads thereof pitched oppositely from the pitch of the threads on the shaft 21. A flexible connecting member 41 connects the two shaft operating arms 32 and 32a together and extends between the rails II and I2, as shown in Figure 1. In this manner the flexible connecting member 4! may be engaged by a, foot so as to press this member downwardly and thereby rock the two arms 32 and 32a toward each other in order to rotate the slide locking shafts El and 21a to a released position. When the two shafts 21 and 27a are in the released position, pressure may be applied from above to the ladder It so as to move one or the other of the

slide members

26 or 45 upwardl and at the same time the opposite slide member will move downwardly into contact with the ground or other uneven surface.

In order to provide a means whereby the lower end of the

slide members

26 and 45 maybe firmly engaged with the ground or surface, I have provided a foot member generally designated as 48, which is secured to the slide member 26. The slide member 45 has a similar foot member 48a secured to the lower end thereof. The foot member 48 comprises a base plate '49 provided with downwardly extending marginal edges or flanges 53 forming a pocket or recess 5|. A rubber friction member '52 is adapted to be seated in the recess 5| and to project below the lower edges of the flanges 59 as shown in Figures 6 and 7. The friction member 52 is provided in the lower face thereof with a plurality of transversely disposed cutouts 53 forming a plurality of spaced apart gripping members '54. The rubber friction member 52 is provided with transversely extending fiber members 55, which coact with the resilient friction elements 54 in resisting sliding movement of the friction member 5| and also constitute a reinforcing means for the gripping members 54.

The plate 49 is provided with a pair of spaced apart parallel ears 56, which engage on opposite sides of the slide member 26 and a bolt 51 engages through the ears 56 and the lower end portion of the slide member 26, so as to thereby pivotally mount the foot member 48 on the lower end of the slide member 26. The slide member 26 at one end thereof is provided with an outwardly extending lug 56, which is formed with a pair of notches 59 in the opposite edges thereof, and a looped foot clamping member 66 is loosely mounted on the lower portion of the slide member 26 and is adapted, as shown in Figure 7, to engage the lug 58 and within the notches 59, so as to hold the foot member 48 in substantially a vertical position, A gripping member 6| is pivotally mounted on the-outer side of the plate 49 adjacent the end thereof oppositely from the lug 58, being pivotally mounted on a bolt or screw 62. A washer 63 is interposed between the head of the bolt or screw 62 and the outer face of the gripping member 6!. The gripping member'SI is formed with a plurality of 'triangularly-shaped teeth 64 and the gripping member 6| is so mounted on the foot 48 that several of the teeth 64 will project outwardly beyond the adjacent flange 50 of the plate 49, as shown in Figure 5. In this manner a relatively sharp friction member or grip element is provided at one end 'of the foot 48 so that if the surface to 'be engaged by the raised so as to bring the gripping member 6| into operative position.

The gripping member BI is held in its adjusted position with respect to the plate 49 by means of a triangularly-shaped locking member 65, which is formed integral with the outer side of the plate 49 and is adapted to engage in the valley between a selected pair of teeth 64. The lower end of the slide member 45 has rockably secured thereto a foot member 480. which is similar in every detail to the foot member 48 and. which may be locked in a raised position by means of a split locking ring 60a in the same manner as the ring 60 is adapted to lock the foot member 48 in the position shown inFigure '7 In the use and operation of this device the two equalizing members I4 and I5 are adapted to be secured to the lower ends of the ladder rails II and I2 with the equalizing members on the inner sides of these rails. The bottom flanges ll of the guide members III are adapted to take up any strain caused by weight of the ladder II) to thereby relieve the attaching bolts 2| and of considerable strain. In the event the equalizing member I4 is on the high side of the ground the flexible connecting member 41 may be pressed downwardly at substantially the middle so as to swing the arms 32 and 32a inwardly toward each other and move the locking shafts 2i and 2M to a released position. The weight of the ladder IE] on the slide member 25 will cause this member to move upwardly in the guide It and at the same time the slide member Q5 will be forced downwardly by the resilient tie member 22, which will move lengthwise of the guide II and to the left as viewed in Figure 1.

When the foot ida is in contact with the depression or lower surface of the ground the flexible member 4"! may be released thereby permitting the shafts 21 and Na to be rotated by their respective rotating springs 34 to a slide locking position. Preferably the inner ends of the shafts 28 are convex, as at 65, and the pressure of the shafts 21 and 21a against the adjacent sides of the

slide members

26 and 45 respectively tightly hold the opposite sides of these slides against relatively soft holding strip 29. The friction members 52 carried by each foot are adaptedto be removably mounted within the recess or pockets ill by means of a plurality of clips or clamping members 61 which engage through recesses 68 formed in the plate 49 and the free ends of the clips 61 are bent inwardly toward each other as shown in Figure 6. The clips 6! engage with the transverse recesses 53 of the friction members 52, as shown in Figure 2.

Referring now to Figures 10 to 13 inclusive, the numeral Illa designates generally a ladder structure including side rails Ila and rungs [3a. An equalizing structure generally designated as I la is mounted on each side rail I Ia on the inner side thereof and adjacent the lower end thereof. The equalizing structure Ma comprises a tubular guide member Iila which is substantially rectangular in transverse section and within which an elongated slide member 26a is slidably mounted. The guide member I6a has the outer wall thereof pivotally secured as by a pivot member 69 to an angle-shaped attaching member generally designated as 10. The attaching member 10 includes a plate II which is adapted to engage against the inner face of the rail Ila and also includes a right angular outer or forward flange I2 secured as by a fastening device 13 to the forward side of the rail Ila. The attaching member 10 also includes a bottom flange 14, which is adapted to engage the lower end of the rail Ila so as to relieve the bolt I3 of strain in the support of the ladder Illa from the slide members 2611.

The pivot member 69 is constructed in the form of a rivet which firmly holds one portion of the guide Ifia on the attaching plate member 10 but permits pivotal adjustment of the guide member IGa on the attaching member 7.0. The guide member I Ed has formed integral therewith a plate I5, which is formed with an elongated slot or opening I6. A transversely extending bolt TI is adapted to engage through the rail Ila and the bolt TI is formed with a reduced threaded stud "I8 loosely engaging in the slot I6. The stud I8 extends through an opening I9 formed in the plate II. A nut is adapted to be threaded onto the stud I8 so that the plate 16 may be locked in its adjusted position with respect to the attaching member Ill. Preferably the position of the plate "i5 is such that the slide member 26a will be inclined inwardly and upwardly as shown in Figure 10. The slide member 26a is adapted to be locked against movement by means of a threaded shaft ill), which is threaded through a boss 28a formed integral with the guide.

plementary splines in the arm 321) the arm 3212 can be adjusted to any desired position with respect to the shaft 26b.

One end of a bowed or U-shaped guide strip 38a is fixed, as at 33a, to the plate "i5 and extends upwardly in the direction of a rung I3a so that the arcuate portion 4Ia of the guide strip 38a will be disposed substantially beneath the rung I3a. In this manner the upper portion Ala of the guide strip 38a will be so positioned that it will not be engaged with a foot of the user of the ladder or form an obstruction which might catch on the foot of the user. A bowed resilient slide strip 42a is secured, as at 43a, to the upper ends of the slide members 26a and has the outer face thereof disposed in sliding contact with the inner face of the bowed guide member 380.. A plurality of guide clips 46a are fixed to the guide strip 38a and engage about the slide member 42a so as to hold the slide strip 42a in sliding contact with the guide strip 38a.

With a construction as shown in Figures 10 to 13 inclusive the equalizing means may be attached to different types of ladders embodying side rails of different widths and the resilient bowed guide and slide strips may be adjusted as shown in Figure 10 so that the upper arcuate portions thereof will be positioned directly beneath a ladder rung. In this manner the upper arcuate portions of these strips will not catch on the foot of the user. In other respects the structure shown in Figures 10 to 13 inclusive is similar to that shown in Figures 1 to 9 inclusive.

What I claim is:

1. An equalizing supporting means for a ladder comprising a pair of tubular guide members, means for securing said members to the opposite sides of the ladder, a slide member in each guide member, a bowed guide strip secured at the free ends thereof to said guide members and extending ipwardly therefrom, a resilient bowed tie member fixed at the ends thereof to the upper ends of said slide members and slidable relative to said guide strip, a gripping foot pivotally carried by the lower end of each slide members, a slide locking member threadably carried by each tubular guide member, yieldable means constantly urging said locking members to a locking position, and a flexible common operating member for said locking members loosely suspended therebetween whereby to simultaneously rotate both locking members to a released position, release of said locking members permitting movement of said slides in opposite directions whereby one foot may be positioned in a different horizontal plane from the other foot to compensate for uneven foot engaging surfaces.

2. An equalizing supporting means for ladders comprising a pair of vertically movable slide members, guide means for said members, means securing said guide means to the sides of the'ladder, means connecting said slide members together for simultaneous movement in opposite directions, a threaded holding member for each slide carried by said guide means, means normally urging each holding member to a slide locking position, a ground gripping foot carried by each slide at the lower end thereof, and a flexible common releasing member for said holding members.

3. An equalizing supporting means for ladders Y comprising a pair of vertically movable slide members, guide means for said members, a bowed guide strip secured at the free ends thereof to said guide members, a bowed tie member secured to said slide members and slidably engaging said guide strip, a foot at the lower end of each slide member, a slide locking member threadably carried by said guide means, a friction element carried by said guide means and engageable with a slide on the side thereof opposite from a locking member, means normally urging said locking members to a slide locking position, and a flexible common releasing member connected with said locking members.

4. An equalizing supporting means for ladders comprising a pair of vertically movable slide members, a guide for each member, means securing said guides to the opposite sides of the ladder, a foot at the lower end of each slide, a movable locking member carried by each guide, means urging a locking member to a normally locked position for looking a slide relative to a guide, and a flexible releasing member connected with each locking member and loosely suspended therebetween.

5. An equalizing supporting means for ladders comprising a pair of vertically movable slide members, a guide for each member, means securing said guides to the opposite sides of the ladder, 2. foot at the lower end of each slide, a rotatable locking member carried by each guide, yieldable means normally rotating a locking member to a slide locking position, and a flexible common releasing member for rotating said looking members to a released position, said releasing "der, afoot at the lower end of each slide, a

threaded locking member carried by each guide,

the threads of one looking member'being oppositelypitched from the threads of the other locking member, yieldable means normally rotating a locking member to a slide locking position, and a flexible common releasing member for rotating said locking members to a released position.

7. An equalizing supporting means for ladders comprising a pair of vertically movable slide members, a tubular guide for each member, an attaching plate for each guide means pivotally securing a guide to a plate, means securing said plate to a ladder side, an arched guide strip connecting said guides together, an arched slide strip connected to said slide members and slidably engaging said guide strip, means engaging a plate and a guide for lockin said guide relative to said plate whereby said guide and slide strips may be positioned beneath a ladder rung, a threaded locking member carried by each guide and engageable With a slide member for looking a slide member against movement relative to a guide, the threads or" one locking member being oppositely pitched from the threads of the other locking member, yieldable means normally rotating a locking member to a slide locking position, and a common releasing member for rotating said looking members to a released position.

8. An equalizing supporting means for ladders comprising a pair of vertically movable slide members, a guide for each member, means securing said guides to the opposite sides of the ladder whereby said guide members may be angularly adjusted relative to the ladder sides, a foot at the lower end of each slide, a rotatable locking member carried by each guide, yieldable means normally rotating a locking member to a slide locking position, and a common releasing member for rotating said locking members to a released position.

9. An equalizing supporting means for ladders comprising a pair of vertically movable slide members, guide means for said members, a bowed guide strip secured at the free ends thereof to said guide members, a bowed tie member secured to said slide members and slidably engaging said guide strip, an attaching plate for each guide, means pivotally securing a plate to a guide whereby said guide means may be angularly adjusted relative to the length of the ladder sides, means locking a plate relative to a guide, a foot at the lower end of each slide member, a slide locking member movably carried by said guide means, means normally urging said locking members to a slide locking position, and a common releasing member connected with said locking members.

HARRY F. HUS'IED.