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Publication numberUS1721521 A
Publication typeGrant
Publication dateJul 23, 1929
Filing dateApr 16, 1926
Priority dateApr 16, 1926
Publication numberUS 1721521 A, US 1721521A, US-A-1721521, US1721521 A, US1721521A
InventorsMarschke Reinhold B
Original AssigneeBerthold V Marschke
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Collapsible and disappearing stair
US 1721521 A
Abstract  available in
Images(3)
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Claims  available in
Description  (OCR text may contain errors)

y 23,.1929- I R. a. MARSCHKE 1,121,521

COLLAPSIBLE m) DISAPPEARING STAIR Filed April 16. 1926 3 Sheets-Sheet 1 given;

attomg R. B. mAscHKs 1,721,521

July 23, 1929.

COLLAPSIBLE AND DISAPPEARING STAIR 3 Sheets-Sheet 2 Filed April 16, 1926 Reinhqld/ B. Marsc'hke gmnhtoa July 23, 1929. R. B.-MARSCHKE 1,721,521

I COLLAPSIBLE AND DISAPPEARING STAIR Filed April 16. 1926 s Sheets-Sheet cs gwoeni oz T 13. R inhold B.Mar.sohke Patented July 23, 1929.

UNITED STATES PATENT OFFICE.

REINHOLD B. MARSCI-IKE, OF ST. PAUL, MINNESOTA, ASSIGNOR T0 BERTHOLD V. MARSCHKE, OF ST. PAUL, MINNESOTA.

COLLAPSIBLE AND DISAPPEARING STAIR.

Application filed April 16,

My invention relates to a. collapsible stair, the primary object of which is to provide a stair which is adapted to fold in a small compact state and to be included as a whole in a unit which is entirely put together at the factory and folded in a compact collapsed package which may be shipped very readily.

A feature of the invention resides in providing a stair which is adapted to operate practically automatically in unfolding and folding up. The unfolding of the stair is a simple operation by engaging a depending member and pulling down on the same, causing the stair sections to unfold and extend downward to the floor below. The stair unit being held and concealed in the ceiling of the room or hallway.

It is also a feature of my invention to provide a stair which is collapsible into com paratively small dimensions, compared to the length of the stair which is accomplished by the sectional construction of my stair. This feature together with the substantial construction which is designed to be sufficiently strong and rigid to support several grown persons at one time is very desirable.

My invention includes lever means associated with adjustable spring members which are adapted to assist in raising and folding the lower sections up to the upper section which includes a stairway having means of folding up after the person walking up the same, so that the lower sections of the stairway can be folded up while the person is still on the uppermost section, by pulling slightly upon the means for raising the lower sections. As these lower sections fold up I provide means for automatically trigping the brace which holds the upper section so that as soon as the lower sections have folded over onto the upper section the whole folded unit stair is drawn up to be entirely concealed in the ceiling supporting the same. I provide a ceiling panel which forms a part of the uppermost section of my stair beneath the treads of the same so that the folded stair unit is concealed by the panel which extends approximately in a plane with the ceiling in which the stair is supported. making a very neat and attractive concealed stairway.

1926. Serial No. 102,594.

My collapsible stair may be easily opened from the top by pressing downward upon the folded sections and stepping into the treads of the upper section, while the spring and lever means which assist in balancing the weight of the lower sections tends to release the lower sections into extended or un folded position, and one may engage the lever means with the hand to permit the lower sections to unfold gradually until the lowermost section extends down and engages with the floor below.

An object of my invention is an adjustable spring means for balancing the sectional portions of my stair so that the same will fold up easily and to provide a spring cushioning means to preventthe stair from snapping open when released from above. This is an important feature of my invention as it provides means for adjusting the spring tension for lifting the free ends of the stair unit. The adjustment of the tension is simple and the construction is inexpensive.

These features, together with other details of construction of my invention and objccts will be more fully and clearly defined in the specification and claims.

In the drawings forming part of my specification:

Figure 1 illustrates my collapsible and disappearing stair in operating position as it is being pulled down from the ceiling above.

Figure 2 illustrates a person ascending my stair.

Figure 3 shows the person having ascended the stairway to the upper section and releasing the lower sections so that they may be pulled up automatically bythe spring balancing and elevating means.

Figure 4 illustrates a perspective view of my stair unit in its compact and collapsed state with the lever and adjusting gear member disengaged from the spring members.

Figure 5 illustrates a front view of my stair, showing the same depending from the cealing above and engaging with the floor below.

Figure 6 illustrates a detail of my adjusting gear member.

Figure 7 is a section on the line 77 of Figure 6.

Figure 8 illustrates a detail portion of the lever attached to the gear and spring n1e1n ber.

Figure 9 is a detail of a port-ion of my stair operating means.

Figure 10 is another detail of a portion of my stair operating means.

Figure 11 is a detail of the adjustable releasing member carried by my stair supporting means.

Figure 12 illustrates a detail portion of one end of the lever arms which are adapted to hold the upper section in locked open position with its operating spring.

Figure 13 is another detail of the lever arm illustrated in Figure 12 from a different direction.

Figure 141 is a side view of one of the hinge members used to connect the lower sections together.

'Figure 15 is an edge view of the hinge illustrated in Figure 141.

My collapsible disappearing stair A is made up in a unit which is adapted to fold into a compact state and of small dimensions.

The unit A is formed with the upper stair section 10 having a series of treads 11 connected to the sides or stringer members 12.

The section 10 is adapted to be inclosed or supported within the casing portion 13 which is rigidly secured within the ceiling of a building and which is provided with a panel or casing 1 1 extending about the same so as to form a finished border about the inwardly extending casing portion which fits into the opening of the ceiling.

.The upper section 10 of my collapsible stair A is formed with a ceiling panel bottom 15 which closes the opening in the casing 13 when the stair A is folded within the casing so as to form a finished closure or ceiling panel.

The ceiling plate 15 closes the stair open ing so that when the stair is folded in the ceiling, the appearance from below is very neat and finished by the ceiling plate 15 and the casing about the same. My stair is provided with an upper section 10. an intermediate section 16 and a lower section 17. The upper section 10, together with the ceiling plate 15 are hingedly connected at 18 to the casing 13, so that the section 10 will drop through the casing when the stair A is opened. A cord member 19 is adapted to depend from the free end of the section 10 and ceiling plate 15 so that by engaging the cord 19, as illustrated in Figure 1 of the drawings, this cord permits the stair A to be lowered at any time from the ceiling.

The master stair section 10 is adapted to be hingedly connected by my peculiarly designed hinges B which connect the stringer members 21 of the intermediate portion 16.

The hinge B is made up of a pair of similarly shaped plate members 22 which overlap centrally and are pivotally connected together at The central overlapping por tions 24: of the hinge B have an arcuated shape on one side so as to place the pivot point 28 slightly above the inturned flanges 25 which are adapted to be connected along the edge of the stringers 12 and 21 and secured thereto. This construction places the pivot point 23 practically in line with the upper edge of the stringers of the stair A and permits the intermediate section 16 to fold over onto the edge of the stringers 12 ol the master section 10.

The lower section 17 of my stair A is adapted to be hingedly connected at 26 by similar hinges B which are secured along the under side of the stringers 21 of the section .16 and the stringers 27 of the section 17. This hinging of the lower section 17 with the hinges 13 connected beneath. the stringers, permits the lower section 17 to fold up against the bottom of the intermediate section 16 when the stair A is being collapsed, as illustrated in Figure 3 and in Figure 4-.

The casing 13 of my stair A is designed to supporta pair of fairly heavy clock springs 28 which are secured by the projecting ends 29 to the upper edge of one end of the casing 18, as illustrated in Figure 4 and as also illustrated in Figure These coil springs 28 are adapted to adj ustab-ly engage with the teeth 30 ot the gears 31 by the inturned inner ends 32 of the springs 28. Each inturned cnd 32 forms a hook which engages lirmly against the teeth 30 of the gear and as the spring contracts about the gear 31 the end 32 is held rigidly locked into engagement with the teeth 30 by the wraps of the coil spring about the same.

The gear 31 is adapted to be attached by the bolt 33 to the operating bar 3%. Lugs 35 (see Figure 6) are formed on the side of the gear 251 which are adapted to form shoulders between which the operating bar extends so that when the bolt 33 is in position to attach the operating bar 3-1 to the gear 31, the lugs will form shoulders be tween which the bar extends so as to permit the bar to rotate the gear in its operation.

Two operating bars 34: are provided in my stair A, one on either side of the stair. These bars connect to the gears 31 which are positioned within the coil springs 28 with the free end 36 of the bars 3% extending toward the hinging point 18 of the section 6 of my stair A.

The free ends 36 of the operating bars 3% are connected to the rods 38. The rods 38 are pivotally connected at 39 to the stringer members 21 of the section 16 just below the hinges B which connect the sections 10 and 16. hen the stair A is connected up with the operating bars 3 as illustrated and the rods 38 are connected to the stringers 21, the coil springs 28 are adapted to term balanc ing means which are adapted to wind up increasing the tension of the springs as the stair A is opened so that when the stair A is in open position. as indicated in Figures 2 and 5, the coil springs 28 are wound quite tight but are not sufiiciently tight to raise the stair from the floor below. In this position. the lower section 17 assists in forming a weight to hold the section 16 in alincment with the section and with the stair A depending ready for use. lVhen the stair A is folded the balancing springs 28 assist in lift ing the sections 16 and 17 and cause these sections to fold together, as is illustrated in Figure 3, it being apparent that as the person walks up the stairs A they can engage the free ends 36 of the bars 34 and lift slightly on the same to start the sections 16 and 17 folding. As soon as the sections are started toward folding position the springs 28 practically operate to fold the same against the section 10.

This means of balancing the lower sections 16 and 17 provides a construction whereby the lower sections are adapted to fold gradually and not with a snap or jerk, being guided, so as to speak, by the operator or per son walking up the stairs, and as the person steps off of the section 10 to the upper floor of the dwelling or building, the sections 16 and 17 will fold over onto the section 10. As the lower and intermediate sections fold over the springs 28 unwind and the weight of the lower and intermediate section is transferred over onto the upper section 10, throwing the maj or portion of the same over the center of the pivot point 39 and causing the lever arms and coil springs 28 to lift up on the free end of the section 10 to close the stair into the ceiling and draw the Ceiling plate up into closed position in the casing 13. This operates automatically and the last part of the folding operation is retarded sufticiently by the weight of the operators arm and handy on the free end of the lever 34 to prevent snapping or jerking in the folding operation of the stair A.

The section 10 provided with a pair of supporting rods 40 which are pivotally secured at 41 and which extend up to the inside of the casing 13 and are formed with a hook end 42 and a transverse shoulder portion 43, as illustrated in Figures 12 and 13.,

A large heavy staple 44 is secured into the sides of the casing 13 and is adapted. to be placed at an angle in relation to the hook 42 and the shoulder as illustrated in Figure 12, so that one side of the staple 45 forms a support and an engagement for the hook 42. This side 45 of the staple 44 also sup ports a spring 46 which is secured in the side of the casing at 47 and the free end 48 of which bears against the side of the rod 40. The other side 49 of the staple 44 forms a stop beneath which the shoulder end of the rod 40 engages when the stair A is opened and the rod 40 slides down through the staple until the hook 42 engages over the portion. 45 of the staple and is forced with the shoulder 43 under the portion 49 of the staple by the spring 46. This positions the free end of the rods 40 as illustrated in Figures 12 and 13 in operation with the staple 44 and thus the free end of the upper section 10 of the stair A is supported by the staple and is locked against folding up until the shoulder 43 is disengaged from the portion 49 of the staple. Thus means for lock ing the free end of the stair section 10 is provided.

In the closing operation of the stair A the lock C which is formed by the staple 44 and the construction and parts associated with the free end of the rods 40, is adapted to be automatically unlocked as the lower sections 16 and 17 fold upward. This is accomplished by the adjustable stop shoulders 50 which are attached to the lower portions of the rods 38. The set screws 51 of the shoulder members 50 are adapted to set these shoulders rigidly attached to the rods 38 as illustrated in Figure 11. The set screw 51 bites against the rod 38, while the yoke por tion 52 which is formed of band-like material engages about the rod 38 and is formed with overlapping inturned end portions hrongh which the set screw 51 passes and engages in the nut 54 which provides the necessary thread engagement for operating the threaded setscrew 51 into and out of engagementwith the rod 38. The lower ends of the rods 40 are offset as illustrated in Figure 10 adjacent the pivot points 41 so that the rods 38 can slide in close proximity to the rods 40 and beneath the same as illus trated in Figure 3.

Thus as the sections 16 and 17 fold in the closing of the stair A, the shoulders 50 strike against the rods 40 just before the sections 16 and 17 fold over onto the section 10, auto matically releasing the lock C on the ends of the rods 40 and causing the operating levers 34 with the coil springs 28 to draw upwardly on the free end of the section 10 and close the stair tight in the casing. l have found my stair to operate so smooth and free owing to the balancing by the spring means 28 and the proper proportioning of the parts and positioning of the operating and supporting rods and lever means that my stair A folds smooth and without a jar or jerk detrimem ml or objectionable to an article of this kind. In fact, the operation is so perfect as to be properly timed in the folding so that a person can walk up the stairs as illustrated in Figure 3, and start the folding of the lower sections after them by lifting slightly on the free ends of the levers 34 and 36 even with one hand on one side, and by the time the person steps off of the section 10, the

lower sections will fold over onto the same and the stair will automatically close tightly and neatly into the casing 13. At this point the balancing and lifting springs 28 are practically released owing to the leverage of the arms 34.

I have provided an adjustable spring operating means so as to adjust the tension of the springs 28 by the gear spring engaging member 31 which is secured to the levers or bars 34. The adjustment is simple as it is only necessary to disengage the gear 31 from the hook end 32 and move the lever 34 to a position so that the hook 32 will engage a tooth which will cause the spring 28 tobe wound tighter when the free end 36 is con- .nected to the rod 38. Thus I provide adjustable tension means for balancing and raising the stair A. This is a very desirable feature of my invention.

In the lifting operation of the lower sections the shoulder 50 is adapted to strike against the arm or rod 40 and automatically release the same from the staple lock C, permitting the upper section to start to fold just as the lower sections slip over onto the section 10. This operation is properly timed by the setting of the shoulders on the rods 38. It is apparent that as soon as the sections 16 and 17 fold over onto the section 10, then the arms 34 will operate with a closing force propelled by the springs 28 to tightly close the ceiling plate 15.

It is desirable in providing a stair of this nature that it be sufficiently compact to be used in a small house or bungalow where the hole is of limited dimensions, that the sections operate in a manner to take up the smallest amount of room in folding; and when folded, and yet provide. a sufficient length of stairs not too steep and to reach the floor properly. At the lower end of the section 17 I provide wheels 55. These wheels permit the lower section 17 to unfold in a manner so that as the free end of the section strikes the floor, the wheels will adjust the sections into the proper position to permit the stair to straighten out, particularly the sections 16 and 17 in relation to each other.

Thus I provide in my stair a unit stairway divided into sections or proportions most desirable to fold properly and to permit the stair to be operated automatically in closing and opening so that a person can come down from the floor above by starting the stair into unfolding position, or the person can walk up the stair and fold the same up after them.

In the connecting up of the operating bars 34 with the intermediate stair section 16 it is important that the location of the pivot point 39 be at a certain posit-ion in relation to the hinging point or connection 23. This permits the proper balancing of the stair A and-it is very essential that the location of this pivot point 39 be in the proper position. I have located the most efficient point for positioning of the end 39 so that my stair will operate to the best advantage.

As the stair A folds the load of the end sections 16 and 17 is transferred to a point closer to the bearing or hinging point 18 of the upper section 10 so that as the springs 28 expand and the tension of the same becomes less, the heavy load of lifting the stair is transferred from the sections 16 and 17 and placedover onto the section 10, so that the folded stair A may be lifted readily and automatically even though thesprings 28 decrease in tension in the closing of the stair. This is an important feature of my invention as it takes off the heavy strain of the springs 28 when the stair is closed and when no great tension is necessary. I have found that this particular construction and arrangement of parts is very important in the proper operation of my stair A. so that the same may operate most eificiently.

I provide a spreader bar which extends across between the ends of the arms 34. This spreader bar 60 is formed with offset portions 62 which form the shoulder means for .operative position and in a manner to hold the same equally spaced apart.

In accordance with the patent statutes I have described the principles and particular features of my invention, together with the best embodiment thereof in the drawings, and while these illustrations show a particular form and construction, I desire to have it understood that these are only illustrative of a means of carrying out my invention and that the same can be applied to other uses than those above set forth within the scope of the following claims.

I claim: 7

1. A collapsible disappearing stair including, three stair sections connected together in a manner to fold onto each other to provide a unit, a ceiling plate secured to one of said sect-ions, a locking and supporting means secured to said ceiling plate section to lock and support the free end of the same, and means for lifting and balancing the other sections in a manner to permit a person to walk up said stair unit and fold the same after him, said folding operation being started by a slight pull on said lifting and balancing means.

2. A collapsible disappearing stair including, a casing frame adapted to be supported in the ceiling of a building, stair sections pivotally secured and adapted to fold onto each other in a manner to be contained within said casing when collapsed, and lifting and balancing means for said stair comarising an adjustable clock-like spring member adapted to engage a tooth member in a manner to adjust the tension of said spring member to vary the lifting and balancing of said stair.

3. A folding disappearing stairway including, a casing adapted to surround said stairway in collapsed position to support the same in a ceiling of a building, a master section of a length approximately equal to the length of said casing, a second section of a length slightly less than said master sec tion, a third section of a length slightly less than said second section, adjustable spring lifting means, means for supporting and holding the free end of said master section depending from said casing in operative position, and means on said lifting means for releasing said master supporting means to permit said lifting means to automatically close said stairway.

4. An operating device for a collapsible and disappearing stair having a master sec tion, including, spring members, lever members adjustably connected to said springmembers, lifting rods connected to said lever members, supporting rods adapted to support and lock the free end of the master section of the stair, and adjustable shoulder means on said lifting rods adapted to automat-ically release the supporting members of said master stair section to permit the stair to fold automatically.

5. A device for lifting and closing a foldable stairway including, clock-like springs, one end of each of which is secured to the casing surrounding said stairway, the other end of which is freely disposed centrally of said spring, a gear adjuster adapted to engage the inner end of said spring, a lever rod connected to said gear, a lifting rod connected to said lever rod, said lifting rod being connected with said stair, whereby the stair may be folded by said lifting device by a slight starting pull on the free end of said operating lever, and said lever can be adjusted in relation to said spring to give more or less tension and lifting power for changing position in relation to said gear.

6. A folding and disappearing stair comprising, a master section, a casing for surrounding and inclosing said master section, an intermediate section, an end section, roller-bearings on the free end of said end section, adjustable lifting spring means connected to said intermediate section, supporting and locking means on the free end of said master section, and adjustable shoulder means for automatically releasing said supporting and locking means, the releasing of the free end of said master section being timed to take place simultaneously with the folding of the intermediate and end sections onto said master section.

7. A collapsible stair structure including a support, a trinity of stair sections hingedly connected together to form a unit, the initial section being hinged to the support, adjustable balancing means mounted upon the support and connected with the free end of the initial section for lifting the same, means mounted upon the support for locking the initial section in a lowered position and means connected with the initial section and the support for automatically releasing said locking means when the stair unit is in the act of folding.

REINHOLD B. MARSCHKE.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2446434 *Aug 17, 1945Aug 3, 1948SncanAppliance for the access into streamline-shaped vehicles
US2536966 *Jun 13, 1947Jan 2, 1951Roy Teller ClarenceLadder or ramp for boats
US4738054 *Nov 18, 1985Apr 19, 1988Milcor IncorporatedCeiling access door assembly
US6662901Jul 18, 2000Dec 16, 2003Franklin J. ApplLadder control apparatus
Classifications
U.S. Classification182/78, 182/19
International ClassificationE04F11/06, E04F11/02
Cooperative ClassificationE04F11/064
European ClassificationE04F11/06A1