US901565A - Combined ladder, step-ladder, and scaffolding. - Google Patents

Combined ladder, step-ladder, and scaffolding. Download PDF

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US901565A
US901565A US40014507A US1907400145A US901565A US 901565 A US901565 A US 901565A US 40014507 A US40014507 A US 40014507A US 1907400145 A US1907400145 A US 1907400145A US 901565 A US901565 A US 901565A
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ladder
strap
bracket
members
ladders
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Hibbard H Thomson
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    • EFIXED CONSTRUCTIONS
    • E06DOORS, WINDOWS, SHUTTERS, OR ROLLER BLINDS IN GENERAL; LADDERS
    • E06CLADDERS
    • E06C7/00Component parts, supporting parts, or accessories
    • E06C7/42Ladder feet; Supports therefor

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  • This invention relates to certain improvements in ladders, whereby a ladder may be readily converted into a ste ladder, or may be employed as a portion 0 a scailolding.
  • the invention Involves certain improvements over the ladder disclosed and claimed in my previous patent, No. 864,044, dated August 20, 1907, and these improvements'involve means for varying the length of the base, means for holding the side bar in its adjusted position, means whereby the ladder may be converted into a step-ladder, and means whereby two lflCldGl'S may be connected toserve as the support of scallolding.
  • FIG. 1 is a perspective view of two of my improved ladders connected to form a seatfolding
  • Fig. l is a side elevation of a ladder havii'ig a jointed section, whereby it may be employed as a ste lrladder
  • Fig. 3 is a perspective view of means employed for rigidly connecting the base member to one of the side members
  • ⁇ l is a fragmentary end. vie-c oi the step-ladder in collapsed form; .llig.
  • FIG. 5 is a perspective view on an enlarged scale showing the im roved means for bolding the sections of t 1e side member in ad justcd position;
  • Fig. 6 is a detail showing the brace employed in connection with the hinge;
  • Fig. -7 is a perspective view of the clamp employed for securing the connecting bars to ladders in forming scaffolding; and
  • Fig. 8 is a pers ective View of one ofthesebars connecte to a ladder round.
  • step-ladder involving the major portion of the present invention constitutes an improvement over that disclosed innny'pre'vious patent, said ladderineludihg side members or rails lll and 11, one of which is extensible and both of which are connected at their lower ends to a base member 12.
  • One feature of my invention involves the means for varying the length of one of these side members and for holding the member in its adjusted position.
  • the side member is rendered adjustable by the employment of a leg 13 held parallel to the body portion of the side member 11 and slidable in respect thereto.
  • Any suitable means as, for instance, a strap 14, may be employed for holding the side member and extension leg together at one point, while at a distance therefrom I employ my improved extension means.
  • this means involves a metal strap or bar having one end 15 rigidly secured to the edge of the side member and extending across the edge of the leg.
  • the strap or bar is here bent to form a loop inclosing the ex tension leg, said loop havin a portion 16 extending across the face of t as log, a trans verse portion extending across the opposite edge, and a portion 17 lying intermediate the member and the leg and preferably secured to the frame. Adjacent the point at which the strap emerges from between the two, it is twisted to form an outwardly-extending bracket 18 lying in a plane at substantiall right angles to the general length of the lad der. The terminal portion of the bar is bent backward toward the side member to form a portion 19 lying substantially parallel to the portion 18 and constituting the remainder of the bracket, -The inner "end of the portion 19 is preferably rigidly connected to the portion 15.
  • a single strap which has both ends thereof connected to the side member, forms a loop inclosing the extension leg, and also forms a bracket extending outwardly therefrom.
  • This bracket constitutes a support for the locking member which preferably comprises a wire bent to form a loop 20 pivoted Within the bracket and between the portions 18 and 1-9 of the strap, and having one of the terminal portions extending through an aperture in the strap and into one of a series of apertures in the edge of the extension leg or in a plate 22 carried by said edge.
  • the opposite end of the wire extends through the bracket at its outer end and constitut'es a handle 23 for the operation of the locklngrnember.
  • the wire preferably carri es a's ring 24;, so disposed as to normally press eopposite end of the wire throng the strap and into the registering a erture of the extension. leg.
  • Thisa justing and locking means to-a la def does not inmarket if it is desired to form one side member of the same extensible.
  • the base member 12 is pivotally connected to one of the side members of the ladder and pivotally and slidably connected to the other member, but to strengthen and reinforce the same and render it more readily adapted for application to ladders already manufactured, I preferably secure said base to the side memhere by cutting a recess in one ofthe lower corners of each side member.
  • the base member extends through, this recess and is held therein by strap 26 having itsends connected, respectively, to the edge and to the end of the side member.
  • the op osite corner of each side member is prefcrab y cut away to form an inclined face 27, so that the corner will not engage with the supporting surface and interfere with the operation of the base.
  • the base at its outer end' preferably carries straps 28 forming loops throu h which a bar 29 may be extended, if it is e- Billed to materially'increase the length of the base member.
  • I preferably provide a series of openings 30 adapted for the reception of a pin carried by the strap 2c of one of the side members.
  • the pin is inserted through the registering apertures to more rigidly hold the parts a ainst strain or accidental dis laccment.
  • he outer ends of the base mom er are preferably connected to the side members at points intermediate the building or when the sections are bent to or s this end into engagement with the
  • the upper sections are preferably stantially one-half the length of the so that when the ladder is bent, the .dnal end B l and the outer ends of the base eniber 12 form three points of support. Tao ladder may thus be firmly set up irrespective of the claraeter or inclination of the supporting surface.
  • fine of the side members of the ladder may have its length r sul; vdd e comes vvaried to bring the ladder to a substantiall upright position, and the ladder maybe fol e intermediate its ends and inclined until the point 34 engages with the ground.
  • I For holding the sections of the ladder in alinement or for holding the sections at an angle to each other to form the step-ladder, I preferably employ'a connecting brace made up of two bars 35 and 36 ivotally connected to the sections of the ladder at points ad'acent the hinge but upon the opposite'e go therefrom.
  • One of the bars, 36,- is provided with a slot 37 adapted for the reception of a pin 38 on the other bar, and also carries a pin 39 adapted for reception in a recess 40 in the bar 35.
  • the brace In the folding of'the sections to form a step-ladder, the brace is first extendedand later shortened, and when the sections assume the position'illustrate-d in Fig. 2, the pin 39 will again enter the recess 40 and prevent the ladder from spreading.
  • the hinge stra s 41'and 42 are referably extended from t e hinge pin to t e outer ends of the brace and are'rigid with their respective sections of the ladder.
  • the bars of the brace lie substantially parallel to thesehinge straps.
  • l may, 'if desired, emplo two of the ladders as sip orts for a scaifo ding.
  • This simpler mechanism involves merely two straps i4. carried by one section of a connecting while one of the sections carries a spring 45 having a pin 46 at its free end ada ted to extend through one of the straps an apertures in both of the sections of the connecting bar.
  • a substantially U-shaped metal clamp 47 is provided, adapted to receive the'end of the connecting bar, and the.
  • ends of the clamp are preferably of spring.
  • a bolt 4-8 is provided, having one end extending through one of the s ring 'ends of the clamp and terminating in a 00k 49 for the reception of the ladder round, and
  • the inner end of the rivet preferably extends inward a slight distance, whereby 1t may engage with the connecting bar to prevent the latter from slipping longitudinally.
  • Two or more of these connecting bars may be emloyed in connection with two ladders, as illustrated in Fig. 1, and the ladders thus converted into supports for a scaffolding.
  • a ladder comprising two side bars, one of said side bars composed of two members slidably connected together, a' strap encircling one of said members but unattached thereto, said strap being rigidly secured to the other member and havinga ortion thereof extending outwardly. to "orm a bracket, and a pm carried by said bracket and movable inrespect thereto and adapted to engage withthe member encircled by said and prevent longitudinal movement thereof. '2.
  • a bar composed of two members slidabl connected together, a metal strap comp etely encirclingone of said members and'rlgidly secured to the other member, said stra havinga portion thereof extending outwar ly to form a bracket and ha'vin an a e'rture therein adjacent the base said bracket and movable through said aper ,ture to prevent longitudinal movement of one member in respect to the other.
  • a ladder comprising two side bars, one of saidside bars composed of two members slidably connected together, a strap com- The end bearing letely encircling one of said members and aving its ends connected to the other member, a portion. of said strap constitutinga bracket, and a spring-pressed locking pin carried by said bracket and adapted to enigage with one of the members and prevent ongitudinal movement thereof.
  • a ladder comprising two side bars, one of said side bars being composed of two members slidably connected together, a metal strap completely encircling one of. said members and iavingits ends connected to the other of said members at one edge thereof, a portion of said band forming a bracket, and a s ring-pressed pin pivotally mounted u p011 sai bracket and having one end thereof adapted for engagement with the member encircled by the strap, and the other end of said pin being disposed at the outer end of the bracket and constituting a handle.
  • each of said means comprising a substantially U-shaped clamp adapted to encircle the brace, and a bolt carried by said clam and having a hook at one end thereof a a ted to engage with a round ofthe ladder, am having means at the op osite end thereof for moving said bolt longitudinally tolock the round and brace to the clamp.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Ladders (AREA)

Description

- 1 H. H. THOMSON. COMBINED LADDER, STEP LADDER, AND-SGAPFOLD ING. APPLICATION IT'ED NOV. 1, 1907.
901,565. Patented Oct. 20, 1908.
2 SHEETS-SHEET 1.
W/TNESSES I INVENTOI? M35 1 J2Z5&ard V .z/zz mo'ora H. H. THOMSON. COMBINED LADDER, STEP LADDER, AND SGAFFOLDING. APPLICATION FILED NOV. 1, 1907.
901,565. Patented 0ct.20,190s.
WITNESSES ATTORNEYS HIBBARD H. THOMSON, OF LAWRENCE, KANSAS.
COMBINED LADDER, STEP-LADDER, AND SCAFFOLDING.
Specification of Letters IPatent.
Patented Oct. 20, 1908.
Application filed November 1, 1907. Serial No. 400,1A5.
To (115 whom it may concern:
Be it known that I, HIBBARD H. Tnonson, a citizen of the United States, and a resident of Lawrence, in the county of Douglas and State of Kansas, have invented a new and 1m )roved Combined Ladder, Step-Ladder, and Scaffolding, of which the following is a full, clear, and exact description.
This invention relates to certain improvements in ladders, whereby a ladder may be readily converted into a ste ladder, or may be employed as a portion 0 a scailolding.
The invention Involves certain improvements over the ladder disclosed and claimed in my previous patent, No. 864,044, dated August 20, 1907, and these improvements'involve means for varying the length of the base, means for holding the side bar in its adjusted position, means whereby the ladder may be converted into a step-ladder, and means whereby two lflCldGl'S may be connected toserve as the support of scallolding.
The invention consists in certain features of construction and con'ibinations of parts, all of which will be fully set forth hereinafter and particularly pointed out in the claims. 4
Reference is to bc had to the accompany.- ing drawings, forniing a partof this specification, in which similar characters of reference indicate oorresp onding parts in all the figures, and in which Figure 1 is a perspective view of two of my improved ladders connected to form a seatfolding; Fig. l is a side elevation of a ladder havii'ig a jointed section, whereby it may be employed as a ste lrladder; Fig. 3 is a perspective view of means employed for rigidly connecting the base member to one of the side members; Fig-5. {l is a fragmentary end. vie-c oi the step-ladder in collapsed form; .llig. 5 is a perspective view on an enlarged scale showing the im roved means for bolding the sections of t 1e side member in ad justcd position; Fig. 6 is a detail showing the brace employed in connection with the hinge; Fig. -7 is a perspective view of the clamp employed for securing the connecting bars to ladders in forming scaffolding; and Fig. 8 is a pers ective View of one ofthesebars connecte to a ladder round.
As previously stated, the step-ladder involving the major portion of the present invention constitutes an improvement over that disclosed innny'pre'vious patent, said ladderineludihg side members or rails lll and 11, one of which is extensible and both of which are connected at their lower ends to a base member 12.
One feature of my invention involves the means for varying the length of one of these side members and for holding the member in its adjusted position. .The side member is rendered adjustable by the employment of a leg 13 held parallel to the body portion of the side member 11 and slidable in respect thereto. Any suitable means, as, for instance, a strap 14, may be employed for holding the side member and extension leg together at one point, while at a distance therefrom I employ my improved extension means. As shown, this means involves a metal strap or bar having one end 15 rigidly secured to the edge of the side member and extending across the edge of the leg. The strap or bar is here bent to form a loop inclosing the ex tension leg, said loop havin a portion 16 extending across the face of t as log, a trans verse portion extending across the opposite edge, and a portion 17 lying intermediate the member and the leg and preferably secured to the frame. Adjacent the point at which the strap emerges from between the two, it is twisted to form an outwardly-extending bracket 18 lying in a plane at substantiall right angles to the general length of the lad der. The terminal portion of the bar is bent backward toward the side member to form a portion 19 lying substantially parallel to the portion 18 and constituting the remainder of the bracket, -The inner "end of the portion 19 is preferably rigidly connected to the portion 15. It will thus be noted that a single strap is employed which has both ends thereof connected to the side member, forms a loop inclosing the extension leg, and also forms a bracket extending outwardly therefrom. This bracket constitutes a support for the locking member which preferably comprises a wire bent to form a loop 20 pivoted Within the bracket and between the portions 18 and 1-9 of the strap, and having one of the terminal portions extending through an aperture in the strap and into one of a series of apertures in the edge of the extension leg or in a plate 22 carried by said edge. The opposite end of the wire extends through the bracket at its outer end and constitut'es a handle 23 for the operation of the locklngrnember. The wire preferably carri es a's ring 24;, so disposed as to normally press eopposite end of the wire throng the strap and into the registering a erture of the extension. leg. To ap 1y thisa justing and locking means to-a la def does not inmarket if it is desired to form one side member of the same extensible.
The base member 12 is pivotally connected to one of the side members of the ladder and pivotally and slidably connected to the other member, but to strengthen and reinforce the same and render it more readily adapted for application to ladders already manufactured, I preferably secure said base to the side memhere by cutting a recess in one ofthe lower corners of each side member. The base member extends through, this recess and is held therein by strap 26 having itsends connected, respectively, to the edge and to the end of the side member. The op osite corner of each side member is prefcrab y cut away to form an inclined face 27, so that the corner will not engage with the supporting surface and interfere with the operation of the base. The base at its outer end'preferably carries straps 28 forming loops throu h which a bar 29 may be extended, if it is e- Billed to materially'increase the length of the base member. Instead-of providing a slotin the basemember to accommodate for a varia-- ticn in the length of one of the side members, I preferably provide a series of openings 30 adapted for the reception of a pin carried by the strap 2c of one of the side members.
After the extension lee has been ad'usted to t 1 o tne oesn'ed position, the pin is inserted through the registering apertures to more rigidly hold the parts a ainst strain or accidental dis laccment. he outer ends of the base mom er are preferably connected to the side members at points intermediate the building or when the sections are bent to or s this end into engagement with the The upper sections are preferably stantially one-half the length of the so that when the ladder is bent, the .dnal end B l and the outer ends of the base eniber 12 form three points of support. Tao ladder may thus be firmly set up irrespective of the claraeter or inclination of the supporting surface. fine of the side members of the ladder may have its length r sul; vdd e comes vvaried to bring the ladder to a substantiall upright position, and the ladder maybe fol e intermediate its ends and inclined until the point 34 engages with the ground.
For holding the sections of the ladder in alinement or for holding the sections at an angle to each other to form the step-ladder, I preferably employ'a connecting brace made up of two bars 35 and 36 ivotally connected to the sections of the ladder at points ad'acent the hinge but upon the opposite'e go therefrom. One of the bars, 36,- is provided witha slot 37 adapted for the reception of a pin 38 on the other bar, and also carries a pin 39 adapted for reception in a recess 40 in the bar 35. With the ladder in its erected position, the bars of the brace are brought into the same straight line and the pin enters the recess 40. In the folding of'the sections to form a step-ladder, the brace is first extendedand later shortened, and when the sections assume the position'illustrate-d in Fig. 2, the pin 39 will again enter the recess 40 and prevent the ladder from spreading.
For reinforcing the ladder adjacent the' hinge and brace, the hinge stra s 41'and 42 are referably extended from t e hinge pin to t e outer ends of the brace and are'rigid with their respective sections of the ladder. When the ladder is collapsed to the position shown in Fig. 4, the bars of the brace lie substantially parallel to thesehinge straps.
Inasmuch as my improved ladder is adapted for firm and steady supportu on any kind of a surface, and as the roun s of the ladder may be brought to a horizontal posi tion irrespective of the character of said sup-- porting surface, l may, 'if desired, emplo two of the ladders as sip orts for a scaifo ding. i
For holding the la rs rigid in respect to each other and in an upright position, I- referablyro'vide two or more connecting ars 43, eac of which is extensible and ada ted to be rigidly connected to a round of the adder. Any suitable means may be employed for varying the length of each of the bars, for
instance, that employed for varying the' length of. the side member of the ladder, or the simpler mechanism illustrated in Fig. 8,.
This simpler mechanism involves merely two straps i4. carried by one section of a connecting while one of the sections carries a spring 45 having a pin 46 at its free end ada ted to extend through one of the straps an apertures in both of the sections of the connecting bar.
For rigidly securing each end'of the connecting bar to the round of a ladder and to render the same readily adjustable, I prefer-- ably provide the mechanism'illustrated in Figs. -7 and 8. A substantially U-shaped metal clamp 47 is provided, adapted to receive the'end of the connecting bar, and the.
ends of the clamp are preferably of spring.
metal and movable slightlytoward and from er and inclosing the other section,
each other. A bolt 4-8 is provided, having one end extending through one of the s ring 'ends of the clamp and terminating in a 00k 49 for the reception of the ladder round, and
i carrying at the other end a cam lever 50 for nally out of engagement with this end of the clamp to facilitate the insertion of the round and the connecting bar. said slot is ireferably reinforced by bendin the termina portion back upon itself, sai
terminal portion being riveted inplace.
' The inner end of the rivet preferably extends inward a slight distance, whereby 1t may engage with the connecting bar to prevent the latter from slipping longitudinally. Two or more of these connecting bars may be emloyed in connection with two ladders, as illustrated in Fig. 1, and the ladders thus converted into supports for a scaffolding. A
' strap suitable plank 52 forming the platforms of the scaffolding, may be supported upon the ladder rounds.
Having thus described my invention, I
claim as new and desire to secure by Letters ing a substantially U-shaped clamp ada ted Iatent: a a c 1. A ladder, comprising two side bars, one of said side bars composed of two members slidably connected together, a' strap encircling one of said members but unattached thereto, said strap being rigidly secured to the other member and havinga ortion thereof extending outwardly. to "orm a bracket, and a pm carried by said bracket and movable inrespect thereto and adapted to engage withthe member encircled by said and prevent longitudinal movement thereof. '2. -In'a ladder, a bar composed of two members slidabl connected together, a metal strap comp etely encirclingone of said members and'rlgidly secured to the other member, said stra havinga portion thereof extending outwar ly to form a bracket and ha'vin an a e'rture therein adjacent the base said bracket and movable through said aper ,ture to prevent longitudinal movement of one member in respect to the other.
A ladder, comprising two side bars, one of saidside bars composed of two members slidably connected together, a strap com- The end bearing letely encircling one of said members and aving its ends connected to the other member, a portion. of said strap constitutinga bracket, and a spring-pressed locking pin carried by said bracket and adapted to enigage with one of the members and prevent ongitudinal movement thereof.
4. A ladder, comprising two side bars, one of said side bars being composed of two members slidably connected together, a metal strap completely encircling one of. said members and iavingits ends connected to the other of said members at one edge thereof, a portion of said band forming a bracket, and a s ring-pressed pin pivotally mounted u p011 sai bracket and having one end thereof adapted for engagement with the member encircled by the strap, and the other end of said pin being disposed at the outer end of the bracket and constituting a handle.
.5. In combination, two ladders, each hav ing two side bars, means for adjusting the length of one of said side bars to each ladder, whereby the ladder ma assume a vertical position irrespective of t e inclination of the su orting surface, connecting braces for holding said-ladders rigid in respect to each other, and means for connecting said braces to said ladders, each of saidjmeans compris- 6. In combination, two ladders, connecting braces for holding said ladders rigid in respect to each other, and means forconnecting said braces to said ladders, each of said means comprising a substantially U-shaped clamp adapted to encircle the brace, and a bolt carried by said clam and having a hook at one end thereof a a ted to engage with a round ofthe ladder, am having means at the op osite end thereof for moving said bolt longitudinally tolock the round and brace to the clamp. of em ybrac etand a locking pin carried by In testimony whereof I have signed my name to this specification in the presence of two subscribin witnesses.
'- IBBARD H. THOMSON.
Witnesses:
' FRA K E.'BANKS,.
CHAS. R. POE.
US40014507A 1907-11-01 1907-11-01 Combined ladder, step-ladder, and scaffolding. Expired - Lifetime US901565A (en)

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3282376A (en) * 1964-12-28 1966-11-01 William W Merriman Mobile platform
US20040003966A1 (en) * 2002-07-08 2004-01-08 Yeoman Wayne J Scaffolding system
US20040222041A1 (en) * 2002-01-07 2004-11-11 Haverfield Corporation Helicopter lineman's ladder
US20060207832A1 (en) * 2004-02-26 2006-09-21 The Boeing Company Ladder Support Apparatus and Methods

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3282376A (en) * 1964-12-28 1966-11-01 William W Merriman Mobile platform
US20040222041A1 (en) * 2002-01-07 2004-11-11 Haverfield Corporation Helicopter lineman's ladder
US6994186B2 (en) * 2002-01-07 2006-02-07 Haverfield Corporation Helicopter lineman's ladder
US20040003966A1 (en) * 2002-07-08 2004-01-08 Yeoman Wayne J Scaffolding system
US20060207832A1 (en) * 2004-02-26 2006-09-21 The Boeing Company Ladder Support Apparatus and Methods
US7328772B2 (en) * 2004-02-26 2008-02-12 The Boeing Company Ladder support apparatus and methods

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