Method, Component and Structure for Constructing a Dual-Use Staircase
A method of converting a traditional staircase into a dual-use staircase, for reducing the stepping height and knee stress in stairs climbing and descending, comprises: providing a plurality of lifting modules and a plurality of extending modules; connecting the plurality of lifting and extending modules in pairs to the original steps respectively; and optionally connecting a plurality of dividers in between said lifting and extending modules respectively. The dual-use staircase structure reduces the step rise by half, while keeping the total run about the same. It allows healthy people to walk in a full-step domain, while allowing people with knee concerns to walk on a half-step domain. The dual-use staircase may include dividers with lateral openings to facilitate reverse turning halfway during ascending or descending of the staircase.
The present application claims priority to U.S. Provisional Patent Application No. 61/316,448 filed on Mar. 23, 2010, the complete disclosure of which is incorporated by reference in its entirety.
FIELD OF THE INVENTIONThe invention is related to a method and structure of modifying an existing traditional staircase for easier climbing and descending with reduced stress on the knee.
BACKGROUND OF THE INVENTIONA traditional staircase with a hand rail on the left is illustrated in
It is well known that walking up or down stairs may cause knee stress and knee pain to certain people. Some healthy elder may comfortably walk around on a flat level, but starts feeling pain in stairs climbing or descending. There were reports showing that walking down a stair can cause more stress on the knee than going up, as the body weight, the step height and the gravity all working together to aggravate the stress on the knee.
There is a comfortable range of the depth and rise of each step for a staircase. The depth is related to the size (length) of a foot, the rise related to a vertical range for raising and dropping a foot with reasonable effort. Examples of typical range of staircase parameters for daily walking of healthy people are: about 6″ to 8¼″ for step rise, about 8¼″ to 11″ or more for step run or depth, less than 45 degrees preferably less than 40 or even 35 degrees) for inclination angle. There are also various guidelines specified in building codes of different countries, but typically within the above range. For some elders or persons with a knee concern, commonly used traditional staircases such as within the above common stairs parameter range still may cause stress and discomfort.
For a tight space the slope of a traditional staircase can become very steep, and the outer portion of an upper tread may substantially overlap with the inner portion of a lower tread. In this case, a toe or a foot may easily get caught at an intermediate step level while walking on the staircase. Especially, when climbing up, a foot needs to retreat first before stepping forward, and descending facing forward (in a typical back-to-the staircase manner) is even more difficult. This steep-slope stairs issue is pronounced at a slope larger than 50 or 60 degrees. It causes difficulty in stairs climbing or descending even for healthy people. And prior-art alternating tread stairs are known to address this issue.
U.S. Pat. Nos. 4,509,617 and 4,981,195 each described a stair having alternate half treads, supported by a central stringer and two parallel side stringers. The half treads on one side of the central stringer alternate with those on the other side of the central stringer. It may be regarded as a traditional staircase with alternatively retreated (or totally disappeared) half treads, such that when walking up or down, a foot will not easily get caught in an intermediate step level due to the openings created by the retreated or disappeared half treads. On the other hand, there are safety concerns of existing alternating tread stairs. A central stringer is a safety issue if making a turn halfway during ascending or descending, as a foot needs to be raised and dropped from one side to another, or a foot may slip over the top edge of the inclined central stringer. If without a central stringer, the sharp inner corners of the half treads further pose a safety threat. In addition, the walking pattern is more complex than traditional staircase. As a result, alternating tread stairs have limited use even for healthy people, primarily for tight-space or steep-inclination applications, such as attic, roof or equipment access, or where one would use a fixed ladder instead.
Neither the traditional-staircase nor the alternating-tread-staircase prior arts have described or suggested a simple method for constructing or modifying a main staircase between floors, suitable for daily use of the whole family members including those with knee concerns. A solution is thus needed for a dual-use staircase to allow a family member with knee concerns to walk in a gentle pace, while allowing other family members to walk in a rapid or regular pace, for daily stairs climbing and descending.
SUMMARY OF THE INVENTIONEasier stair climbing and descending can be achieved by: reducing the step rise of a traditional staircase, which results in less knee bending and hence reduced knee stress. The challenges include keeping the same tread depth and about the same total run.
To accommodate the needs of family members, with or without knee-stress concern in stair climbing or descending, an existing traditional staircase can be modified and converted to meet the needs of both.
Add-on parts can be provided to raise a first portion of a tread about half a rise, and to extend a second adjacent portion of the tread outwards about half a step depth. An array of said second portions from each step forms a full-step domain (FSD), with a commonly-used and comfortable step rise, step depth and stairs inclination angle, suitable for house members without knee issues to walk in regular pace. Another array of the first portions, combining with adjacent parts of the second portions, form a half-step domain (HSD), suitable for house members with knee concerns to walk in a half-rise, half-run, gentle pattern.
Alternatively, an original staircase can be fabricated with a pre-cut cavities, about half rise and half depth measured from a step nose (outer edge), for a portion of the width of each step. This allows easy modification of the staircase as a dual-use staircase for reducing stress in climbing and descending.
Dividers, preferably arranged with a number of lateral (or sideway) openings, serve as a blocking barrier to avoid a person walking in the FSD from wandering into the HSD, while allowing a comfortable turn halfway during climbing or descending in the HSD based a lateral opening design.
The present invention provides a viable alternative solution for reducing knee stress in stairs climbing and descending without adopting a more expensive and power-consuming solutions like elevator, escalator or chair lift.
Accordingly, a first objective of the invention is to provide a method and structure, for converting an existing traditional staircase, such that the stepping rise and knee stress can be reduced while keeping the total run about the same.
A second objective of the invention is to allow co-existing of a full-step domain and a half-step domain, in a dual-use staircase, such that persons without any knee problem may comfortably and efficiently walk in the full-step domain, while persons with knee concerns may walk in a gentle half-step domain.
A third objective of the invention is provide an improved divider structure for the dual-use staircase structure, to avoid persons walking in the full-step domain wandering into the half-step domain, and to allow a person walking in the half-step domain making a comfortable turn halfway during climbing or descending.
A first preferred embodiment for converting a traditional staircase 110 into a dual-use staircase 100 is illustrated in
The traditional staircase 110 includes a plurality of N original steps 111 of a full width W1, each original step has an original tread 111b, an original depth (or first depth) D1 and an original rise (or first height) H1. A first portion of the stepping surface of the ith original tread 111b is raised for a raised height H5 and thus forming a first adjusted tread 125 of a first partial width WS1, for i=1 to N−1. A second portion of the stepping surface of the jth original tread 111b is extended outwards for an incremental depth D5 and thus forming a second adjusted tread 135 of a second partial width WS2, for j=1 to N. As shown in
The raised height H5 is within 35% to 65% (preferably about half) of the first height H1 of an adjacent original step; and the incremental depth D5 is within 35% to 65% (preferably about half) of the first depth D1 of an adjacent original step. Similarly, the raised height H6 is within 35% to 65% (preferably about half) of the first height H1 of the first-stage original step.
According to the first preferred embodiment, the methods of forming the first adjusted treads 125 and second adjusted treads 135 can be achieved by employing add-on parts including a plurality of lifting and extending modules as described in more details below.
As shown in
As illustrated in
Preferably, the extending modules are wider than the lifting modules. The lifting module has a smaller width, sufficient for one foot of a first person to comfortably stepping on with a hip clearance to the hand rail. The extending module has a larger width, suitable for another foot of the first person and another person to step on simultaneously. Preferably, WS1 be in the range of 9.5 inch to 12 inch, alternatively in the range of 8¼ inch to 14 inch, with WS2>2×WS1. Accordingly, the first partial width WS1 is less than 40% of the full width W1 of an original step. Thus, with the hand rail still within reach, the array of second adjusted treads forms a full-step domain (FSD) for healthy people to walk up and down the stair in a regular pace. The array of first adjusted treads and the adjacent small portions of the second adjusted treads form a half-step domain (HSD), suitable for people with knee concerns to climb or descend with substantially reduced stepping height.
As an example, for walking up in the HSD, the left foot will step on a lifting module then the right foot will step on an adjacent portion of a next higher extending module. It can be easily seen, from the left step to the right step there is only half a rise and half a run stepping as compared to walking on the original staircase. Since the stress on a human knee can increase rapidly with the step rise and vice versa, the dual-use staircase thus greatly reduces the knee stress by cutting both the rise and stepping size in half. This is particularly beneficial for persons with knee-stress concerns or elders with limited motion capability. Once getting used to the new, dual-use staircase, walking up and down the stairs can become a comfortable and gentle exercise rather than a stressing routine.
A plurality of dividers 140 connected in between extending modules 130 and lifting modules 120 respectively are also shown in
The first and second adjusted treads 125 and 135 can be formed over a traditional staircase based on common raised floor architecture, and supported and connected by, for example, frames, frameworks, posts, floor levelers, etc. However, this involves custom fit works that may be time consuming since each original step 111 may not have identical dimensions even within the same original staircase. Alternatively, it can be built with pre-fabricated parts, preferably with adjustable dimensions and adjustable interconnecting positions.
As shown in
Similarly, the extending modules may have height and depth adjustability. As shown in
Also illustrated in
As illustrated in
As shown in
A second implementation method for constructing a dual-use staircase involves cutting a half-height/half-depth cavity for a small portion (width) of a step. As will be illustrated in more details in
Furthermore, preferably the add-on parts as described use inter-locking attachment design including, for example, concealed fastening, grooves or rails for snapped-on, slide-in or screw-tight attachment. Preferably, the lifting and extending modules of multiple or all steps are interconnected together for overall strength and sturdiness of the dual-use staircase. The foot levelers of the main supports of lifting or extending modules can be glued to the existing treads of a conventional staircase with strong bonding while allowing later removal. It is also preferred that the add-on parts and interconnection fixtures allow later removal for easy restoration of a dual-use staircase to its original state.
Claims
1. A method of converting a traditional staircase into a dual-use staircase, the traditional staircase having a plurality of N original steps, each original step having a first tread, a first depth and a first height, comprising:
- raising a first portion of the first tread for a first raised height and thus forming a first adjusted tread of the ith original step, for i=1 to N−1;
- extending a second portion of the first tread outwards for a first extended depth and thus forming a second adjusted tread of the jth original step, for j=1 to N; wherein
- said first adjusted treads being lined up and forming a first array of stepping surfaces;
- said second adjusted treads being lined up and forming a second array of stepping surfaces; and
- the first array being adjacent to the second array.
2. The method of claim 1, further comprising:
- raising an adjacent portion of a stepping surface of a lower-level floor for a second raised height; wherein
- the adjacent portion being adjacent to the first adjusted tread;
- the second raised height being within 35% to 65% of the first height of the first original step; and
- the first raised height of the ith original step being within 35% to 65% of the first height of the (i+1)th original step; wherein
- 0<i<N.
3. The method of claim 1, wherein
- the first extended depth of the jth original step being within 35% to 65% of the first depth of the (j−1)th original step; wherein
- 0<j<N+1.
4. The method of claim 1, wherein
- the step of forming the second adjusted tread including disposing another tread partially overlapping the first tread and extending outwards for the first extended depth.
5. A method of converting a traditional staircase into a dual-use staircase, the traditional staircase having a plurality of original steps, each original step having a first tread, a first depth and a first height, comprising:
- providing a plurality of lifting modules for connecting to the original steps respectively, wherein each lifting module having a second height less than the first height;
- providing a plurality of extending modules for connecting to the original steps respectively, wherein each extending module having a third height matching the first height within a 5% tolerance and having a third depth less than the first depth; and
- connecting the plurality of lifting and extending modules in pairs to the original steps respectively.
6. The method of claim 5, wherein
- each second height being within 35% to 65% of the first height of an adjacent original step; and
- each third depth being within 35% to 65% of the first depth of an adjacent original step.
7. The method of claim 5, wherein
- each lifting module including at least one of a first main support, a first height adjuster, a stacking layer or their combinations for adjusting said second height.
8. The method of claim 5, wherein
- each extending module including at least one of a second main support, a depth adjuster, an extendable part or their combinations for adjusting said second depth.
9. The method of claim 5, wherein
- the original steps having a full with W1;
- the lifting modules having a first partial width WS1;
- the extending modules having a second partial width WS2; and
- WS1<(W1×40%).
10. The method of claim 5, wherein
- the original steps having a full with W1;
- the lifting modules having a first partial width WS1;
- the extending modules having a second partial width WS2; and
- (WS1+WS2)<(W1×60%).
11. The method of claim 5, further comprising:
- connecting a plurality of connector bases to said original steps respectively; and
- connecting each connector base to at least one of said extending modules, lifting modules or their combinations.
12. The method of claim 11, wherein
- the step of connecting each connector base to at least one of said extending modules, lifting modules or their combinations including using at least one of pins, pin holes, tongues, grooves, or their combinations for the connection.
13. The method of claim 5, further comprising:
- connecting a plurality of dividers in between said extending and lifting modules respectively.
14. The method of claim 13, wherein
- the plurality of dividers being lined up and forming at least one lateral opening.
15. A method of converting a traditional staircase into a dual-use staircase, the traditional staircase having a plurality of original steps, each original step having a first tread with an outer edge, a first depth, a first width and a first height, comprising:
- forming a cavity in each original step from a portion of the outer edge with dimensions of a second height downwards, a second depth inwards and a second width in a lateral direction;
- connecting a plurality of annex modules to said original steps next to the cavities respectively; wherein a third top surface of each annex module aligns with a second top surface of an adjacent cavity; and further comprising
- forming a second tread over each aligned second and third top surfaces.
16. The method of claim 15, wherein
- for each original step, the second height being within 35% to 65% of the first height; and
- the second depth being within 35% to 65% of the first depth.
17. The method of claim 15, wherein
- said second treads being lined up in an array; and
- for each original step, the second width being less than 40% of the first width.
18. A set of components for converting a traditional staircase into a dual-use staircase, the traditional staircase having a plurality of original steps, each original step having a first tread, a first depth and a first height, comprising:
- a plurality of lifting modules for connecting to the original steps respectively, wherein each lifting module having a second height less than the first height of an adjacent original step;
- a plurality of extending modules for connecting to the original steps respectively, wherein each extending module having a third height matching the first height within a 5% tolerance, and having a third depth less than the first depth, of an adjacent original step; wherein
- the plurality of lifting and extending modules being formed for connecting to each other in pairs and for connecting to the original steps respectively.
19. The set of components as in claim 18, further comprising:
- a plurality of connector bases for connecting said pairs of lifting and extending modules to the original steps respectively.
20. The set of components as in claim 18, further comprising:
- a plurality of dividers for connecting in between said lifting and extending modules respectively.
Type: Application
Filed: Mar 23, 2011
Publication Date: Sep 29, 2011
Inventor: Shi-Tron Lin (Irvine, CA)
Application Number: 13/070,435
International Classification: E04F 11/022 (20060101);