CA2106275A1 - Trestle ladder - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE
TRESTLE LADDER

A trestle ladder comprised of a front side having a front top. The trestle ladder is also comprised of a rear side having a rear top. The rear top is hingedly connected to the front top.
The trestle ladder is also comprised of a foldable platform connected to the front side and the rear side. The platform is preferably spring loaded such that it folds up when the front side and rear side are brought together to be in a folded state. The trestle ladder is also comprised of a top bar connected to the rear top. Preferably, the platform includes a first portion having a first end connected to a front side of the ladder and a second end connected to a rear side of the ladder. The first portion has a folded state and an open state. The first portion defines a plane when it is in the open state. The platform preferably also includes a hinge mechanism connected to the first portion such that the first portion goes between the open state and the folded state by rotating about the hinge mechanism. The present invention also pertains to the folding platform, the top bar, and the hinge themselves.

Description

--` 21Q~27~

TRESTLE LADDER

OF THE INXENTION

~ he present invention is related to trestle ladders.
More specifica~ly, the present inventîon i~ related t~ ~ trestle la~der havang a ~pring-loaded ~olda~le platform with a pinchless hin~e and a top bar.

Tres~le lad~ers h~Ye a plat~orm upon which use~s cli~b to a~d ~tand on during operation. ~fter operation has ~een completed, the ladder is ~olded up and remo~ed. When the ladder is ~olded up, the platorm folds up also. In order for the platform to fold up spreaders a~e used but have the potential to pinch ~he use~ i~ a portion of his skin become caugh~ in ~he spreader. Furthermore, ~ on lar~e:trestle ladd~s ~o~er six ~eet ~all) due ~-o t~eir weight : 15 and their height it i~ sometimes dificuIt to fold up t~e platform as the ladder is folded up.

: ~ Addi~ionally, the top of the laddex has a support ~
~ fortify ~he stxuctural integrity o~ ~he ladder. ~his s~pport is ;: :sa~e~i~ea incor~ec~ly us~d ~ USQ~S a~ another s~ep ~f the }adder ~O and ~tepped on in some ~a~hion to ex~end the o~erational range ~f the user~

~ he present inYention involYeS ~ trestle ladd~ar ~ha~
a preferred embodiment has a platfo~m that au~omatic:ally ~olds up wi~h~the:às i~tan~ ~f springs when the ladd~r is olded up. ~n addition, ~h~ platform ha a pin~hles~ h~nge and a support ~ar at the la~der top to fur~h~r prov1de ~a~e~y to a u--r.

--` 2~e627~

~ h~ present in~en~ion pertain~ to a trestle ladder. ~he ~re~le ladder'-is co~prlsed of a fro~ ~ide having a fron~ ~op.
~he trestle ladder i~ also compri~ed o~ a rear side hav~ng a reax top. ~he rear ~p is hingedly ~onnected to thR fro~ ~Op. ~he tres~le lad~er i8 also ~omprised of a ~oldable platform connected to the ~ron~ side and the re~r side. The pla~oxm i~ pre~erably spring loaded such tha~ it ~olds up w~en the front side and rear : ~ide ar~ brough~ ~ogether to be in a folded state. P~e~e~a~ly, the plat~ox~ includes a first portion havin~ a first end connected to a fron~ side of the ladder and a second end aonnected to a rear side o~ the ladder. The ~irst portion has a folded state and an open state. The fiXst portion defines a plane ~hen it is in the open s~ate.
.
1~ ~he platform preferably also includes a hinge mechanism connec~ed to ~he f~rst portion such that the first portion goes between the open stat~ and the ~olded state ~y rotatinq abou~ ~he hinge mechanism. The hinge mechanis~ preferably in~lud~s a first ~and~se¢ond hinge. Each hin~e i5 compri~ed of a ~irst hinge side and~a second hin~e side. Each hin~e side has a central portion.
The aentral portion ls.comprised o~ a ~irst s~ct~on having a first height and a ~e~nd ~ection havin~ ~ second heigh~. Th~ second ~ hei~ht is 1QS~ than the first height. ~he aentral portion O~ the - ~ irst hinge~side mates with the cen~ral poxtion of the second hinge ~5~ side:~su~ that the firs~e¢tion o~ the ~irst hinge side ali~ns . al~ngsidc:~h~;~irst sec~ion of the ~econd hinge side and is : dispos~d~:ovex ~he second se~on of the~second hinge side and the :~ Pirst~section of ~he first hinge side is disposed over ~he second : :section of~the first hinge side. The~ firs~ section of each h~n~e 3:0 s~de is able to slide along the respecti~e second sec~ion when the ~ir~t and seaond hinge sides are mated and rotated relative to ea¢h 21 9~.~7~

o~her until the ~irst sections con~act e~¢h other which S~Op5 fur~he~ relativ~ xotation o~ the ~irst hinge side an~ the econ~
hinge side.

~he trestle ladde~ is also ~o~pxised of a top bar conneated to the rsar top. ~he to~ bar is prefer~bly co~prised of an elongate ~em~er having at lea~t a portion o* its s~rface ha~ing a radius of curvature in a ~irst end and a ~econd end. The top b~r is also preferably comprised of an attachmen~ portion disposed on either end of the memPer through which the elongate mem~er is aonnected to ~he ladder. The present invention also per~ains to the:folding pla~orm, the top bar, and the hin~e themselves.

BI~IEFJ:~SC~IP?ION. OF ~E ~ INGS

In th~ accompan~ing drawings, the preferred e~bodiment o~
: . the::invention and Fre~erred methods of practicing the invention are illustrated in which:

.
: Figure la is a schemati~ representati~n ~f a trestle ladder~or the pre~en~ ~nvention. :
.
~ Figure lb is a sc~ematic representation of a per~pective v~ew o~ an upper portion o~ th~ txestle ladder~
:
~Q Figure 2a is an overhead ~iew o~ a ~op ba~.

: Figure 2b i~ an ~al ~iew of the top bar.

Figure 3a is an overhe~d schema~ia view of a platform of ~he present invention.
:
Figure 3b is a ~ide view o~ the pla~form.

~1 0~7~

~ i~ure 3c is a ~ront ~id~ ~iew o~ a firs~ element of ~e pl~tf orm .

Fi~re 3d is a right ide! view o~ the platform.

~ igure 3e is a right side ~iew of a -~econd element of the 5 plat~orm~

Figure ~ is a schematic rep~esen~ation ~f an axial view of a ~uar~ p~rt~on.

~lgure 5a is a side vertLcal view of a spring. ~ :

Figure 5b iS a side horizontal Yiew of a spring.

lo Figure 5a is an axial ~riew o~ a ~3pring.

: Figure 6a is a schematic representation of an axial view o~: a side of a hinge.

Figure 6~ i8 a ~:hem~ic ~epreQe~ntation o~ a side vi~w of a ~id~ of ~e hin~e.

~15 : ~ ~ FLg~lre 7 is ~ schematic ~presentak~on o~ an exploded view of:~ a :~pring in ~laSion to an L brac~e and a ~olding platfcrm.

Fi~ure ~a is a schematic rep~e~entation of a front and &i~e~:view of a trestle ladde~ wit:h spreaders.

:: Fls~ure~ ~b is a ~chematic representation of a ~ preader ~0 attaaheà to a ~restle ~adder.

::

,:

_; ` 210~27~

Ra~erring now to the drawing~ wherein like referene numerals refer ~o similar or identical parts throughout ~he several views, and more specifically to figure la thereo f, there is shown a ~chematic represen~a~ion o~ a perspea~ive view of a trestle ladder 1~. The trestle ladder 10 ha~ a front side lZ having ~
front top 14. ~he trestl~ ladder lO is al~o comprised of a reax side 16 having a rear top 18. ~he xear top 18 is hingedly connected to the front top 14. The tres~le ladder 10 ~ also comprised o~ ~ foldable platfor~ ~0 connected to the front side 12 and the rea~ side 16. The platfo~m 20 is preferably spring }oaded 5uch tha~ it folds up when the front ~ide 12 and ~he rear side 1~
ar~ braugh~ tog~ther ta be in ~ folded ~ta~e. Addi~ionally, the trestle ladder 10 is preferably comprised o~ a tap bar 22 15: preerably connected to the rear top 18, as shown in fiqure lb, : altho~gh it could be co~nected to the front top 14.

~he top bar 22 is prefera~ly comprised o~ an elongate membex 24 with at least a portion o~ its 5urface 26 having a radius o~curva~uXe, and a first end 28 and a second e~d 30, as ~h~wn in 2igure 2a,:whi~h is an overhead ~iew o~ the ba~ 22. The top bar 2~
~ also pre~erably aomprised o an attachment par~ion 32 disposed at either end of the elon~ate me~ber 24 through which the elongate ~ : member~24 i8 connected to the le~t rear top 18, as shown in figure : 2b,~: which~:is an end ~iew of the top bar 22. Preferably, the elon~a~e member 24 has a hollow cylindrical shape having an axis 34,:~wi~h the atta~h~Qn~ portion 32 at ei~her end extend~ng radially fr~m:the ~urface 26 of the elonga~e member 24 ~owards the axis:34 o~ the elongate me~eX. ~he attac~ment portion 32 at either end of ~he:~elongate member 24 preferably inaludes a stem 36 that exte~ds radially towards t~e axi5 34 and a tubular type portion~:38 having an axis connected to t~e:end 40 o~ the stem 36 opposite tbe end 42 ::

~: .

2~275 -6~

o~ the stem 35 conneated to the surface 26 of ~he elongate me~ber 24 ~uch ~hat the t~bular ~ype p~rtion'-~ axis is ali~ned wi~h and ove~lap~ 'che elongate member'~ axis 34. The ste~ 36 and tubular type portion 38-preferably extend axially fxom the firs~ end ~8 to ~he secon~ end 30 of ~he elon~ate ~ember 24. Prefera~ly, the ~ub~la~ type portion 38 ha~ a C ~hape. 5qrews 144, for ins~an~e, can en~er the tubulax type por~ion 38 throu~h the rear top 18 to ~iX the bar 22 to the rear top 18, a~ shown in figure 2~.

The folding platform 20, as shown in ~igure 3a, i~
preferably co~p~ised of a flrst portion 44 ~aving a ~irst end 46 connec~ed to the front side 12 of ~he ladder 10 and a second end 48 conn:ected to the rear side lh o~ the ladder 10. ~he firs~ portion 44 has a folded state and an open state~ The irst por~ion 44 defines a plane 50 when it i~ in the open state, as shown in figure 3b, which is a side view of the plat~orm 20 ~n ~he open st~te.
Preferably, the platform 20 automatically folds up as t~e front side 12 and the rear ~ide 1~ are brou~ht toqe~her to ~e in a folded s~ate. The plat~orm 20 is also pr~ferably prel~aded in a direa~ion towards the front top 14 and r~ar top 18 which causes the pla~form 20 to a~to~atically ~old up as the ~ront side 12 and rear sid~ 1¢
are brough~ ~ogether to ~e i~ a folded state.

Pla~form 20 preferably includes springs Which are connected to the platform 20 that preloa~ the platform 20. T~e ~ prin~s Qply a force to the ~olding plat~orm ~0 which causes the platform 20 ~o automatically ~old up as the front side 12 and ~ear side 16 aXe brough~ ~ogether to be in a folded sta~e. ~he sprin~s are pre~erably ~rs~on spring~ ~0349 which apply a tor~Ue at 30=5.1S0 in-lb. (Springs can be omit~ed from t~e pla~orm so that i~ i5 not prelo~ded.) There can be a ~ir~t front ~il 3pring 114 connected to a ~ t front side rail 86 and the underside o~ the plat~orm 2~, a ~cond ~ront rail pring 116 conneated ~o a 6econd ~ 2~Q~7~

front side rail 88 and t~e underside of the plat~orm 20, a first rear rail ~pring ll~ a~nnea~ed to a firs~ rear side rail 90 and to the und~rside ~f the pla~orm 20, and a second rear raîl spring 12 c~nnecSed t~ a-second rear side rail 92 and to the under~ide 83 o~
the platform 20, as depicted in figures la, 3b and 7.

Pre~erably, in 8, 9 and 10 foo~ tre~tle ladders 10, there are included spreaders 143 as shown in figures ~a and 8h. There i~
a spreade~ 143 connected to the fi~t ~ront xail ~ and ~he first rear rail 90, and a spreader 143 connected to the second front rail 88 and ~he ~ec~nd rqar rail g2, as is well known in the art. When a trestle ladder 10 ha~ spreaders 143, in order to place th~
trestle ladder 10 in a folded state, each spreader 143 is l~o~ened at its center 145 so it can pivot about its c~nter pin 14~ and end pins :149, and ~old ~p as ~he front side 12 and the rear side lfi are brought:together. In order to secure a trestle l~dder lo having spreadex~ in an open state, the oen~r 14S i5 tightened by clamping it $n a:stiff position. ~he spre~ders 143 are typically po6itioned ~etween ~he ~iddle s~eps of the ~restle ladder 10.
.
~ he folding plat~orm 20 pre~erably is comp~ ~ed of a ~0 hinge mechanism 5~ ¢onneated to the first portion 4~ such that the i~ por~i~n 44 ~oes between the open gtate and the folded ~ate :~ - by~rotating about the hing~ me~hanism 52. Pre~era~ly, the ri~st : ~ po~tion~44~deines an up6ide down V shape when in the folded state.
: ~ ~ e~;:hl~nge mechanism S2 i8 preferably not connected to ei~hox the fr~nt side ~2 or t~e xeax side lÇ of ~he ladder 10.

: : The fixst p~xtion 44 i~ preferably ~omprised of a:first : el~ment 54 having a first side 56 conneated to t~e ~ron~ side:12 o~
the ladder 10 and a second ~ide 58 connected to the hin~e me~hanlsm 52.~ The ftrst portion 44 i~ also comprised of a se¢ond ele~en~ ~0 30 ~having a first ide 2 aonno~ed to the re~r s1de i6 o~ the ladder ~` 210~27~

.

10 and a second side 64 ~onnected to the h~nge mec~anis~ 52 and oppo~ing the second side 58 of the first element 54. ~a~h element prePerably hs~ an opening 6~ which can ~e used to grip and pull 'the respective element when ~he first portion 44 is in the open state and ¢ause the first portion 44 to enter into the folded -~ta~e.

There is pxeferably a guard por~ion ~4 disposed ~etwean ~he first element 54 and second element 60, as shown ~n f igure 3c and figure 4. The portion ~4 prevents a por~ion o~ a personls ~ody, suah as the f ingers ~rom get~ing caught between the econd : 10 ele~ents ~nd po6sibly being in jured i~ ~he plat~orm 20 folds ~p.
The guard portion 94 has a stub 95 wh~ch extends from a guard element g7. The stu~ gS and guard element 97 prefera~ly extend the length of the second side 58. The stub ~5 ~its into the first element 54 and extends out an opening in ~he second side 58 of the : 15 firs~ element 54.
~ .
In ~n al~erna~i~e embodiment, when the first po~tion 44 is in an open state, the guard po~tion ~4 ~s pres~ressed ~y thQ
~e~o~d elem~nt 60 pressing down against it~ By the guard portion 94 ~being prestre~ed, it aause~ the first portio~ 44 to au~ma~i~ally enter the folded state when the first portion 44! no longer defines thQ pl~ne 50 ~nd ~he front ~ide ~2 and rea~ side 1~
:~r~ ~rouqht together. In this embodiment, ~o springs are neces~ary ~ina~ the pre t~essed guard portion 94 pro~ides the force to the ~irst port~on 44 the~prings ~ould otherwise provide.

Preferably, ea~h element 54, ~0 is comprised of a first m~er 6R and a second me~er 70 ~onn~cted together and hela ~n spaced~rèlationshtp With a bracket mechanism 72. Eaoh me~er h~s an ~nderside 8~ and a top side 83. The ~irs~ member 68 and the ~econd~member ~0 a~e aligned adja~ent each o~her and define the 30 r~spective opening 66, as shown in ~gure 3a. The first member 68 . . .

~ 210527S

of the ~irst element 54 is dispos~d adjacent to the front ~ide 12 and ~he ~irs~ ~e~ber ~8 of the seo~nd elemen~ 60 i~ dispo~e~
adjacent the rear side 16. The second member 70 o~ the firs~
elemen~ 54 and of the second element 60 are disposed adja~en~ the hinge mechanism 52. Each ~e~er ~an be made of plastic, sheet metal, wood or pre~erably aluminum, or a co~bination thereof, co~ponent~ of the ladder 10 can also be made of t~e same.

The braoket mechanism 72 preferably includes a first ~racket 74 connected ~o a ~irst edge 76 o~ each member, for instan¢e ~i~ rivets, and a second ~raeket 78 connected to a second edge 80 o~ ea~h member, as shown in igures 3a and 3e. The hinge ~echanism 52 is prefera~ly ~o~prised of a first hinge 82 connea~ed to each first bracket 74 and a second hinge 84 connected to each : second bracket 78. The first bracket 74 of the first elemen~ 54 is ~onnected to the first front side rail R6 of the front side 12, the second brac~et 78 of the irst element 54 is connected to the second ~ront side rail ~8 of the ~ront side 12, the first bra~ket 74 of thQ sec~nd element ~0 is ~onnec~ed to the fiXs~ rear ~ide rail 90 of the rear side 1~, anq a sea~nd bracXet 78 o~ ~h~ second e:lement 60 is conne¢ted ~o the -~econd re~ side rail 92 of ~he re~r side 16. The second ~ront s~de rail 88 is in spaced relationsh~p and in parallel wi~h the ~irst ron~ side rail 86 an~ ~h~ second rear side rail g2 is in spaced ~elationship and in parallel with the fir~ rear side rail ~0~ Ea~h bracket i~ cqnnected to a 2S r~spective ~id~ ~ail p~eferably with L~braces 1~1.

With respect ~o ~prings 114, 11~, 118, 120, each ~pring has a central sprinq por~ion 122, as shown in fi~uree 5a, 5b and 5c. Each spring also has a ~ixst hoo~ 124 which ex`tend~ f~om a : first:~side 126 and at~aches to a r~spe~tive ~rac~e~. ~a~h sprin~
:30 additionally has a second hoo~ 128 whioh extend6 fxo~ a seco~d side 130 of the central spring portion la~ and at~aches to a respective 2~Q~27~

L-brace, pre~erably at ~he ~ottom ~f the L-brace 141, as shown in f~gure 7 ~ A bolt 129 ex~end~ through ~he L-~race 141, cen~ral spring portion ~ of ~he spring and the brac~et and holds them in operational p,o~ition.

Pre~era~ly, the hinge 82, 84 i-~ comprised of a ~irs~
hinge sid2 9~ and a second hinge ~ide 98, as ~hown in figures 3a and 3d. Each hinge side has a central portion 100, as ~hown in ~igures 6a and Cb. ~he central portion lO0 is comprised of a fi~st section 102 having a fi~st height and a second sec~io~ 104 ha~ing a se~ond height. The second height is preferably les~ than the first height. The central portion 100 of the fixst hinge ~ide ~6 mate~ with the cen~ral portion 100 of the ~econd hinge side 98 such tha~ the first section 102 of t~e first hinge side 96 align~
alon~ide the ~irst section 102 of the ~econd hinge side ~ and is disp~sed over the second section 104 o~ the second hinge side g8, and the first se~tion 102 of the second hinge side ~8 is di~posed over the second section 104 of ~he fi~st hlnge side 96. The ~irst s~c~ion 102 of each hinge side is ,a~le to ~lide alon~ the respective second sec~ion 104 when the ~lrst and second hinge sides are ma~ed and rotated relati~e to each other until th~ first ~ecti~ns ~on~t each other which stops f~r~her relative rotation a~ the ~irst hinge side g6 and seçond hi~e ~ide ~8.

~ ~ach cen~ral portion loa of each nin~e ~ide p~eferably `~ has a~circumference def~ned ~ an edge 106. The edse 106 of each ~5 ~en~ral por~ion lO0 aligns with and contacts ~he edge 106 of the other central portion 100 creating a closed oentral ~ection housing :108 with:the firs~ and seaond sections therein ~hen the first and second hinge sides are mated. Preferably, the ~irst seation 102 of each hin~e side is in the form of a bloak that extends f~om the second cection 104. ~The ~econd section 104 deines a surfa~e of the Fen~ral ~or~ion 100. Addlti~nally, ea~h hinge side has a wing 210~27~

110 whiah extends from the central portion 100~ The win~ 110 o the first hinge ~de 96 extends in parallel b~t oppositely with respect to the wing 110 of the ~econd hinge side 98 when th~ hin~e sides a~e mate~ such tha~ th~ winys 110 define a line 11~ with the S central section housing 108 ex~ending bel~w the linq 112, as Rhown in figure 3b.

The front side 12 pre~era~ly incl~des steps 13~ whiCh are used to climb the ladde~ 10. Each s~ep 132 is connected to ~he first fron~ side rail 86 and ~he seaond f~on~ side rail 88. ~he rear side lfi preferably also includes steps 132~ Eaah step 132 i~
oonnecte~ to the ~irst rear ~ide rail 90 and the seaond rear ~ide rail 92. Each side ~ail prefera~ly has a foot 134 attached to i~s bottom end 136 to allow ~he rail ~o be~ter grip a surface upon whic~ it rests. There can also be braces 138. The ~ra~es 13~ are u ed to conneat s~ep~ 132 to respecti~e rails. The platform 20 is : also connected to each rail ~hrou~h a brace 138. Each L-brace 1~1 is disposed in a plane esse~tially perpendicula~ to a plane in which the braces 138 are disposed.
.
AdditiQnall~, the ladder 10 can inclu~e a irst top angle 140 and a se~ond top an~le 142. The first top angle ~40 is hlngedly connec~in~, far instance wi~h pin as~embly 14~, the ~irs~
fron~ side rail ~6 A~ it~ ~Op ~0 the first rear side rail 90 at i~s top, ~he seco~d top angle 142 is ~im11arly hingedly connecting th~
se~ond~front 6ide rail 88 at its ~op to the second rea~ side ra~-l ~2 at its top.

~ In ~he operation of the invention, a trestle lad~er 10~
a~ 6hown in ~igure la, is placed in a des~red position ~y ~he user.
The user then ~ecures the ~res~le:ladder 10 by moving the frant side 12 of the ladder 1o relati~e to the rear side 16 such that the ladder fo~ms an upeide down v and assu~es an open state. The ron~

` 2~0~27~

side 12 moves relati~e to the rear side 16 by the first ront rail 86 and se~ond front rail 88, which are in parallel and sp~ced relationship ~ith each other and conn~cted by steps 132, rotating abou~ first top an~le 140 and second top angle 142, respe~tively, as shown in figure lb. FurthermoXe, also ~onneoted to ~irst top angle 140 is first rear rail 90 and also conneated ~o the second ~op angle 1~2 i5 the second rear rail 9Z which is in parallel and spa~ed relationship with firs~ rail gO and aonnected ~hereto with steps 1~3. Since the fi~st front rail 86 and the e~ond ~ront rail 1`0 88 along ~ith steps 13~ form ~he front side 12 and first rear rail 90 and second rear rail 92 along with step~ 133 form the ~ear side 16, when the front side 1~ mo~e~ while ~he reax side 16 stays still or moYes less than the front side 12, ~here is rela~ive movement ~etween the ~ront side 12 and the rear side 16.
.
The upside ~own V shape assumed by the open ladder 10 is securely held in p~sition on the g~ound by way of feet 134 on the ~ottom 136 ~f ea~h rail. The fee~ 134 provide anti-skid contact betw~en the ladder and the ~ro~nd. Addi~ionally, ~he top angles only allow rela~ive rotation of the Pron~ and rear side~ a predetermined amount, as do~s the platform 20. Platform 20, whos~
pri~ary functi~n is to ~Uppor~ a usex a~ an elevated hei~ht abo~e the gr4und, additionally p~ovid~s ~urther support ~ the trestle ladder when i~ is in an open position by ~eing atta~hed ~o th~
~rall~ and preventing them from f~rther ~eparating.

: The platform 20 is ~omprised of a first element S4 and a seco~d element 60, a~ shown in igure~ 3a-3e. ~he ~irst element 54 is aomprised of a firs~ mem~er 68 and a ~e~ond member 70. ~he fixst m~mber 68 and s~cond member 70 are held together with a first bra~et 74 aIong a first ed~e 76 of each me~ber and a second ~racket 78 at~ched along a ~econd edge 8~ o~ each member. The firs~ bracket 74 and ~ec~nd bra~ket 78 are rivete~ to the ~irst ~; 2~0~27~

~ro~t r~ 6 and ~econd ~ront rail 88, r~spe~tively, along th~
~iræt side 56 of ~he fir6t membe~ ~8 o~ th~ first element S4.

Be~ween thè ~ir~t mem~er 68 and second member 70 i8 an open~ng ~ in which the user can grip ~he plat~o~m and pull it up when the user desires ~o fold up the ladder lo~ To facilitat~ the grlpping, ~he ~econd side 59 of ~he ~lr t member 6~ is curved t~
conto~r wi~h t~e user' hand when the usex rea~hes through the openi~g 66 to grab the pla~form 20.
.

First bracket 74 and second bracket 78 are attached to the wing~ ~lo of first hinge 82 and seaond hinge 84, respe~tively, a}ong ~he second ~ide 58 of the second member 70 of the firs~
element 54. Positioned along the sec~nd side 58 is a guard por~ion -: 94; to p~event a user's fingers or other body portion from gettin~: caught~between the seGond side 58 of the second me~Per 70 of eit~er : 15 the irst~element 54 or second ele~ent 60, as shown in figuxe 4.In~a:similàr ~ashion, the seqond element 60 of the ~la~form 20 i posit~ioned relati~e to the first rear rall 4Q, second rear rail 92 and ~irst hinge 82 and sec~d h~nge 84, As the ladder lo is un~olded, the first hinge side 9~ of ~20 :each hinge~ rotates xelat1ve to ~he second hin~e 5ide 98: until a :~: f~xs~ se~tion 102 of the fi~Rt ~ins~e side g6 abuts the first se~tior~ 102 of 'che second hinge ~ide 98, as shown in ~i~xes 6a and 6~ hen:~ eaoh first section 102 a~ut~ the othe~, the hinge cannot rotate any ~llrther and ess~ntially the ~inge loaks in place wi~
~espect~:to ~hat p~si~ion and in that direc~on of ~ovement. Also as~the~:platfo~m i8 cpened so that the ladder 10 Gan open, fir~t : spring~ 4, second spring 116, third spring 11~ and ~our~h spring 120 are~compressed against ~irst front ~ail 8~, se~ond ~ront rail ~ 88,~flrst rear rail ~0 and second r~ar rail ~2, respecti~ely. Each spring,~hich is a t~rsion spring, has a firs~ hook 124 which~

` ~lQ527~

.

attaches to a r~spec~ive ~ra~et. ~entral spring por~ion 122 o~
ea~h sp~ing i~ then position~d betwee~ the bracket and the res~eative L-bra~e 141 which is riveted ~o the respective rail, w~ th a second llook 128 extending ~rom the central spring porti~n and atta~hing to ~he respective L-~rac~, as shown in ~$gures 5a-5c and figure 7. The compresged spring~ preloa~ the plat~orm 20 by pushing a~ainst the respectlYe L-bra~s 141 so the platfor~ 20 i~
ready to fold when ~he user begin~ to move the ~ron~ ~ide 12 towar~s the reax side 16. The platfor~ 20, when it i~ in a fully open position and forms the plane 50 essentially locks in place s~
the spring~ do not ~feat ~he platfor~ 20 and place it ln an unstable po5ition.

Once the trestle ladder is o~en and in place, ~he user ~hen cl~mbs up the s~eps 132 on the fron~ side 12 and stands on th~
lS platform 20. Any urge by ~he user to ~tand on or place weigh~ on the top kar 22 is elLminated since the top bar 22 is n~t flat but ~ounded and painted red to clearly indica1:e that i~ is ~ot m~ant ~o be stood on or have weigh~ placed on it. The ~op bar 22 i~
~nne~ted to the rear top ~8 ~y screws 144 that pa5s ~hrough each top angle and en~er the tubula~ portio~ 38 of ~he stem 3~ o~ the elon~a~e me~ber ~4 of the ~op ~a~ 22, as show~ in ~igures 1, ~a and 2b~

. After the user has aompleted hi~ work, he climb5 down the steps 132 of the ~ront side 12. He then grab~ ~he platform 20 2S through the opening 66 and pull~ up on the platfo~m 20. The ~ompr~s~Dd sp~ngs apply ~heir bUilt-up ener~y aqainst the underside 83 of ~he platfoxm 20, ~acilita~ng ~he ~los~re o~ the plat~or~ as thQ front side 12 and reax side 16 are Pro~g~t ~o~ethex,. ~e ~olded ladder lo i~ ~hen ;?ic~ced up by the u~er and 30 aarried ~o th~ neXt loaation where the use~ can repeat the aho~e opeXation.

`--; 210~27~

Wi~ respect to actual di~ensions of the various compc~nent~ of the prefer~ed e~odiment, they are a~; follow$:

Top Bar 2 2 A 13015"
B l. 250"

Plak~m 20 . Gua~d Portion 94 C 13 . 06~5" ~ 60 D l5.653" N l~l40"
E 7 . 826" o ~ 440ll F 7 . 4511' P .1~5"
G . 75" Q . 2~0" DIA
H l. 104" R l~ 370"
3 ~ ~5" S . 130" ~AD
J S . 791" ~ . 700" R~D
1~ X . 3125" U ~ 015" 3~AD
L . 5 ~

:` Sprlng ~Iinge Y . 875" ~C . 2S0"
~D ~ . 21~"
~ ~434" PIA AE .313"
~33 ~ 62S"
.1~91~ ~G 2 .~;28"
A~ .875" I~H~2~5" DIA
AB . 3125" ~I . 460" ~AD
2$ ~ 45"
~X 1. 0~
a~h .743" RAD
.8~5"
: ~ ` :
Although the inventi on ha been descrih~d ill detail in 30 the~ ~oregoinçF e~od~ten~ for ~he purpose o~ illus~ratiotl, it is t:~
~ e unders1:ood ~hak Such de~ail ~s s~lely for that purpQse and that ~ ~ variation~: can Pe made t:~erei~ by those stcilled in ~he àr~ wi~hou~
~leparting ~rom t~.e 6pirit and 8c:0pe of the invent:lon exc:ept as~ i~
aay b~ desaxlb~d~ y tne followin$~ claims.

.

. ~

Claims (49)

1. A folding platform for a ladder comprising:

a first portion having a first end connected to a front side of the ladder and a second end connected to a rear side of a ladder, said first portion having a folded state and an open state, said first portion defining a plane when in the open state; and a hinge mechanism connected to the first portion such that the first portion goes between the open state and the folded state by rotating about the hinge mechanism.

2. A platform as described in Claim 1 wherein the first portion defines an upside down V shape when in the folded state.

3. A platform as described in Claim 2 wherein the hinge mechanism is not connected to either the front side or the rear side.

4. A platform as described in Claim 3 wherein the first portion is comprised of a first element having a first side connected to the front side of the ladder and a second side connected the hinge mechanism; and a second element having a first side connected to the rear side of the ladder and a second side connected to the hinge mechanism and opposing the second side of the first element.

5. A platform as described in Claim 4 wherein each element has an opening which can be used to grip the respective element when the first portion is in the open state and cause the first portion to enter into the folded state.

6. A platform as described in Claim 5 wherein each element is comprised of a first member and a second member connected together and held in spaced relationship with a bracket mechanism, which are aligned adjacent each other and define the respective opening, said first member of the first element disposed adjacent to the front side and said first member of the second element disposed adjacent the rear side, said second member of the first element and of the second element disposed adjacent the hinge mechanism.

7. A platform as described in Claim 6 wherein the bracket mechanism includes a first bracket connected to a first edge of each member and a second bracket connected to a second edge of each member.

8. A platform as described in Claim 7 wherein the hinge mechanism is comprised of a first hinge connected to each first bracket and a second hinge connected to each second bracket.

9. A platform as described in Claim 8 wherein the first bracket of the first element is connected to a first front side rail of the front side, the second bracket of the first element is connected to a second front side rail of the front side, the first bracket of the second element is connected to a first rear side rail of the rear side, and the second bracket of the second element is connected to a second rear side rail of the rear side.

10. A platform as described in Claim 9 wherein each member is made of extruded aluminum, plastic or stamped sheet metal.

11. A platform as described in Claim 10 wherein each member has an underside and a top side, and including a first front rail spring connected to the first front side rail and the underside of the platform, a second front rail spring connected to the second front side rail and the underside of the platform; a first rear rail spring connected to the first rear side rail and to the underside of the platform; and a second rear rail spring connected to the second rear side rail and to the underside of the platform which cause the platform to be preloaded in a direction towards its top side.

12. A platform as described in Claim 11 wherein each spring has a central spring portion, a first hook which extends from a first side of the central spring portion and attaches to a respective bracket, and a second hook which extends from a second side of the central spring portion and attaches and presses against a respective L-brace of the ladder.

13. A platform as described in Claim 12 including a guard portion disposed between the first element and second element.

14. A platform as described in claim 10 including a guard portion disposed between the first element and second element such that when the first portion is in an open state, the guard portion is prestressed to cause the first portion to enter the folded state when the first portion no longer defines the plane.

15. A hinge comprising:

a first hinge side, and a second hinge side, each hinge side having a central portion, said central portion comprised of a first section having a first height and a second section having a second height, said second height less than said first height, said central portion of said first hinge side mating with said central portion of said second hinge side such that the first section of the first hinge side aligns alongside the first section of the second hinge side and is disposed over said second section of said second hinge side and said first section of said second hinge side disposed over said second section of said first hinge side, said first section of each hinge side able to slide along the respective second section when the first and second hinge sides are mated and rotated relative to each other until the first sections contact each other which stops further relative rotation of the first hinge side and second hinge side.

16. A hinge as described in Claim 15 wherein each central portion of each hinge side has a circumference defined by an edge, said edge of each central portion aligning with and contacting the edge of the other central portion creating a closed central section housing with the first and second sections therein when the first and second hinge sides are mated.

17. A hinge as described in Claim 16 wherein the first section of each hinge side is in the form of a block that extends from the second section, said second section defining a surface of the central portion.

18. A hinge as described in Claim 17 wherein each hinge side has a wing which extends from the central portion, said wing of said first hinge side extend in parallel but oppositely with respect to said wing of said second hinge side when said hinge sides are mated such that the wings define a line with the central section housing extending below the line.

19. A top bar for a ladder comprising:

an elongate member having at least a portion of its surface having a radius of curvature and a first end and a second end; and an attachment portion disposed at either end of the member through which the elongate member is connected to the ladder.

20. A top bar as described in Claim 19 wherein the elongate member has a hollow cylindrical shape having an axis, with the attachment portion at either end extending from the surface of the elongate member towards the axis of the elongate member.

21. A top bar as described in Claim 20 wherein the attachment portion at either end of the elongate member includes a stem that extends radially towards the axis and a tubular type portion having an axis, connected to the end of the stem opposite the end of the stem connected to the surface of the elongate member such that the tubular type portions's axis is aligned: with and overlaps the elongate member's axis, said stem and tubular type portion extending axially from the first end to the second end of the elongate member.

22. A top bar as described in Claim 21 wherein the tubular type portion forms a C shape.

23. A trestle ladder comprising:

a front side having a front top, said front side having a first front side rail, and a second front side rail in spaced relationship and in parallel with the first front side rail;

a rear side having a rear top, said rear side having a first rear side rail, and a second rear side rail in spaced relation hip and in parallel with the first rear side rail, said rear side rear top hingeably connected to said front side front top such that the front side and the rear side can fold about their top to become parallel with each other, and unfold about their top to form an upside down V shape; and a folding platform attached to the front side and rear side which automatically folds up as the front side and rear side fold about their top.

24. A trestle ladder as described in Claim 23 wherein the platform is ]preloaded in a direction towards the front and rear top which causes the platform to automatically fold up as the front side and rear side fold about their top.

25. A trestle ladder as described in Claim 24 wherein the platform includes springs which are connected to the platform that preload the platform.

26. A trestle ladder as described in Claim 25 wherein there is a first front rail spring connected to the first front side rail and the underside of the platform; a second front rail spring connected to the second front side rail and the underside of the platform; a first rear rail spring connected to the first rear side rail and to the underside of the platform; and a second rear rail spring connected to the second rear side rail and to the underside of the platform.

27. A trestle ladder as described in claim 26 wherein each spring has a central spring portion, a first hook which extends from a first side of the central spring portion and attaches to the platform, and a second hook which extends from a second side of the central spring portion and attaches and presses against a respective side rail.

28. A trestle ladder comprising:
a front side having a front top;

a rear side having a rear top, said rear top hingedly connected to said front top;

a folding platform connected to the front side and the rear side, said platform spring-loaded such that the platform folds up when the front side and the rear side are brought together to be in a folded state; and a top bar connected to the rear top.

29. A trestle ladder as described in Claim 28 wherein the platform includes:

a first portion having a first end connected to a front side of the ladder and a second end connected to a rear side of the ladder, said first portion having a folded state and an open state, said first portion defining a plane when in the open state; and a hinge mechanism connected to the first portion such that the first portion goes between the open state and the folded state by rotating about the hinge mechanism.

30. A trestle ladder as described in Claim 29 wherein the hinge mechanism includes a first and second hinge, each hinge is comprised of a first hinge side, and a second hinge side, each hinge side having a central portion, said central portion comprised of a first section having a first height and a second section having a second height, said second height less than said first height, said central portion of said first hinge side mating with said central portion of said second hinge side such that the first section of the first hinge side aligns alongside the first section of the second hinge side and is disposed over said second section of said second hinge side and said first section of said second hinge side disposed over said second section of said first hinge side, said first section of each hinge side able to slide along the respective second section when the first and second hinge sides are mated and rotated relative to each other until the first sections contact each other which stops further relative rotation of the first hinge side and second hinge side.

31. A trestle ladder as described in Claim 30 wherein the top bar is comprised of:

an elongate member having at least a portion of its surface having a radius of curvature and a first end and a second end; and an attachment portion disposed at either end of the elongate member through which the elongate member is connected to the rear top.

32. A trestle ladder as described in Claim 31 wherein said front side having a first front side rail, and a second front side rail in spaced relationship and in parallel with the first front side rail; a rear side having a rear top, said rear side having a first rear side rail, and a second rear side rail in spaced relationship and in parallel with the first rear side rail

33. A trestle ladder as described in Claim 32 wherein the spring-loaded platform includes springs which are connected to the platform that preload the platform.

34. A trestle ladder as described in Claim 33 wherein there is a first front rail spring connected to the first front side rail and the underside of the platform, a second front rail spring connected to the second rear side rail and the underside of the platform; a first rear rail spring connected to the first rear side rail and to the underside of the platform; and a second rear rail spring connected to the second rear side rail and to the underside of the platform.

35. A trestle ladder as described in Claim 34 wherein the front side includes steps, each step connected to the first front side rail and the second front side rail; and the rear side includes steps, each step connected to the first rear side rail and the second rear side rail.

36. A trestle ladder as described in Claim 35 wherein each side rail has a foot attached to its bottom end to allow the rail to better grip a surface upon which it rests.

37. A trestle ladder as described in claim 36 including braces and L-braces said platform connected to each rail through a brace and an L-brace.

38. A trestle ladder as described in Claim 37 including a first top angle and a second top angle, said first top angle hingedly connecting the first front side rail at its top to the first rear side rail at its top, said second top angle hingedly connecting the second front side rail at its top to the second rear side rail at its top.

39. A trestle ladder as described in Claim 38 wherein the hinge mechanism is not connected to either the front side or the rear side.

40. A trestle ladder as described in Claim 39 wherein the first portion is comprised of a first element having a first side connected to the front side of the ladder and a second side connected to the hinge mechanism; and a second element having a first side connected to the rear side of the ladder and a second side connected to the hinge mechanism and opposing the second side of the first element.

41. A trestle ladder as described in Claim 40 wherein each element has an opening which can be used to grip the respective element when the first portion is in the open state and cause the first portion to enter into the folded state.

42. A trestle ladder as described in Claim 41 wherein each element is comprised of a first member and a second member connected together and held in spaced relationship with a bracket mechanism, which are aligned adjacent each other and define the respective opening, said first member of the first element disposed adjacent to the front side and said first member of the second element disposed adjacent the rear side, said second member of the first element and of the second element disposed adjacent the hinge mechanism.

43. A trestle ladder as described in Claim 42 wherein the bracket mechanism includes a first bracket connected to a first edge of each member and a second bracket connected to a second edge of each member.

44. A trestle ladder as described in Claim 43 wherein the first hinge is connected to each first bracket and the second hinge is connected to each second bracket.

45. A trestle ladder as described in Claim 44 wherein each member has an underside and a top side, and including a first front rail spring connected to the first front side rail and the underside of the platform, a second front rail spring connected to the second front side rail and the underside of the platform; a first rear rail spring connected to the first rear side rail and to the underside of the platform; and a second rear rail spring connected to the second rear side rail and to the underside of the platform which cause the platform to be preloaded in a direction towards its top side.

46. A trestle ladder as described in Claim 45 wherein each spring has a central spring portion, a first hook which extends from a first side of the central spring portion and attaches to a respective bracket, and a second hook which extends from a second side of the central spring portion and attaches and presses against a respective L-brace of the ladder.

47. A trestle ladder as described in Claim 46 including a guard portion disposed between the first element and second element.

48. A trestle ladder as described in Claim 47 wherein each central portion of each hinge side has a circumference defined by an edge, said edge of each central portion aligning with and contacting the edge of the other central portion creating a closed central section housing with the first and second sections therein when the first and second hinge sides are mated.

49. A trestle ladder as described in Claim 48 wherein the elongate member has a hollow cylindrical shape having an axis, with the attachment portion at either end extending from the surface of the elongate member towards the axis of the elongate member.