Patent Application
20240318497
The present invention relates to door hardware, and more specifically to door hardware having ligature resistant characteristics, in that it is difficult for ropes, cords, wires, articles of clothing or other pieces of material (hereinafter referred to as “ligatures”) to be anchored to the door hardware, whether intentionally or unintentionally, to cause harm to persons having access thereto. Even more particularly, the present invention relates to a swinging door system of the type often found on bathroom stalls and the like that possesses such ligature resistant characteristics.
In many environments, such as, for example, although not limited thereto, medical facilities, prisons, schools, offices, government buildings, residences, and other institutions, there exists a population of people at risk of committing suicide. In many psychiatric hospitals, for example, patients have been known to attempt suicide, specifically hanging, while in the care of the institution.
These suicide attempts are known to have involved the use of doorknobs, hinges and other door hardware, particularly since an effort is often made to remove other ligature anchor points from the facilities. Institutions have many private rooms where such a suicide attempt may take place, such as bathrooms. Every private room cannot be watched at the same time without enormous staff resources. Therefore, private rooms, and specifically door hardware in these rooms, provide an area of opportunity for suicide attempts.
The problem of suicide attempts has been addressed in some institutions by simply removing all door hardware, and even the doors themselves. In some cases, door substitutes (such as, for example, curtains sewed with hook and loop fasteners) are employed instead of doors. While this may reduce the opportunity for suicide attempts, it likewise eliminates all privacy and security.
The Institute for Patient Centered Design (http://www.institutepcd.org/) identifies the four pillars of primary patient and family needs as: safety, patient empowerment and respect, connection to nature, and access to natural light. While a door may not have the same obvious impact as lighting and other design elements of a room, use of a door instead of a door substitute, or nothing at all, supports the concept of patient empowerment and respect, ultimately providing a safe opening solution that enhances the wellness journey.
Thus, what would be desirable instead would be door hardware that allows for a swinging door to operate in much the same way that traditional swinging doors operate (particularly, allowing for privacy and security), while at the same time obviating at least some of the traditional ligature anchor points.
These objectives have been achieved to a large extent by our own U.S. Patent Application Publication No. US 2022-0282565 A1, titled “Ligature Resistant Swinging Door System,” in which is provided a swinging door assembly that includes a frame mount, a door panel, and a pivot assembly operably connecting the door panel to the frame mount such that the door panel is pivotable in two opposite directions from a closed position to first and second opened positions. When the door panel is pivoted in the first direction by an angle less than a threshold angle, or is pivoted in the second direction by an angle less than the threshold angle, the door panel is biased toward the closed position by virtue of a weight of the door panel, and when the door panel is pivoted in the first direction by an angle greater than or equal to the threshold angle, or is pivoted in the second direction by an angle greater than or equal to the threshold angle, the door panel is no longer biased toward the closed position.
In U.S. Patent Application Publication No. US 2022-0282565 A1, however, it is disclosed that various different, but traditional, door panel configurations may be employed. As is known, however, these traditional door panel configurations are generally configured (i.e., materials and dimensions are selected) such that the door panels are substantially rigid. Indeed, conventional wisdom in the art has been for door panels to be carefully and particularly designed to be rigid, and it has long been thought that flexibility should be avoided. We have discovered, however, that a problem may arise in this case, in that no matter how small the gap is made between the free edge of the door panel and the corresponding edge of the door opening when the door is in the closed position (with ⅛″ being a common example), this gap may be used as ligature anchor point.
More specifically, a person intent on self-harm may tie a knot in a rope, cord, bed linen, piece of clothing, or the like, and then close the door thereon. Because traditional door panels are substantially rigid, the gap between the free edge of the door panel and the corresponding edge of the door opening may act as a ligature anchor point, such that a significant amount of force may be placed on the knotted rope, cord, bed linen, piece of clothing, or the like, thereby resulting in the potential for self-harm.
What would be desirable would be if this potential ligature anchor point, defined by the gap between the free edge of the door panel and the corresponding edge of the door opening when the door is in the closed position, could be obviated, such that relatively high forces could not be sustained by this potential ligature anchor point, thereby resulting in a reduced risk of substantial self-harm.
Accordingly, it is an object of the present invention to provide a swinging door system of the type often found on bathroom stalls and the like that allows for the door to operate in much the same way that traditional swinging doors operate (particularly, allowing for privacy), while at the same time obviating the need altogether for at least some of the traditional ligature anchor points.
It is a more specific object of the present invention to provide such a swinging door system that reduces the likelihood that the gap between the free edge of the door panel and the corresponding edge of the door opening, when the door is in the closed position, could be used as a ligature anchor point capable of supporting high enough forces to allow for substantial self-harm.
These and other objectives are achieved, in accordance with a first aspect of the invention, by providing a ligature resistant flexible swinging door assembly comprising a frame mount, a flexible door panel, and a pivot assembly operably connecting the door panel to the frame mount such that the door panel is pivotable in a first direction from a closed position to a first opened position and is pivotable in a second direction, opposite to the first direction, from the closed position to a second opened position. The door panel is formed from a flexible polymeric material having a modulus of elasticity between 250 and 470 ksi (1.79 and 3.24 GPa), a flexural yield strength between 5220 and 15000 psi (36 and 103 MPa), a flexural modulus between 141 and 450 ksi (0.971 to 3.10 GPa) and a flexural strain at yield between 7.00% and 7.20%. The door panel has a width of between 26 and 42 inches (66.0-106.7 cm) and a thickness of between 0.040 and 0.315 inches (1.0-8.0 mm).
In some embodiments, the door panel has a thickness of between 0.0625 and 0.250 inches (1.6-6.35 mm). In some embodiments, the door panel has a thickness of between 0.0938 and 0.1875 inches (2.38-4.76 mm). In some embodiments, the door panel has a thickness of between 0.1094 and 0.1563 inches (2.78-3.97 mm). In certain of these embodiments, the door panel has a thickness of about 0.1250 inches (about 3.18 mm). In other embodiments, the door panel has a thickness of about 0.1181 inches (about 3.0 mm).
In some embodiments, the door panel has a width of between 26 and 30 inches (66.0-76.2 cm), whereby the swinging door assembly is adapted to be installed in a door opening having a width of about 30 inches (about 76.2 cm). In some embodiments, the door panel has a width of between 32 and 36 inches (81.3-91.4 cm), whereby the swinging door assembly is adapted to be installed in a door opening having a width of about 36 inches (about 91.4 cm). In certain of these embodiments, the door panel has a width of about 34 inches (about 86.4 cm), whereby the swinging door assembly is adapted to be installed in a door opening having a width of about 36 inches (about 91.4 cm).
In some embodiments, the door panel has a thickness of between 0.1094 and 0.1563 inches (2.78-3.97 mm) and the door panel has a width of between 32 and 36 inches (81.3-91.4 cm), whereby the swinging door assembly is adapted to be installed in a door opening having a width of about 36 inches (about 91.4 cm).
In some embodiments, when the door panel is pivoted in the first direction by an angle less than a threshold angle, or is pivoted in the second direction by an angle less than the threshold angle, the door panel is biased toward the closed position by virtue of a weight of the door panel, and when the door panel is pivoted in the first direction by an angle greater than or equal to the threshold angle, or is pivoted in the second direction by an angle greater than or equal to the threshold angle, the door panel is no longer biased toward the closed position.
In certain of these embodiments, the first opened position is defined by the door panel being pivoted by about 90° in the first direction with respect to the closed position, and wherein the second opened position is defined by the door panel being pivoted by about 90° in the second direction with respect to the closed position. In certain of these embodiments, the threshold angle is about 60°.
In some embodiments, the pivot assembly comprises: a first pin disposed adjacent a top edge of the door panel and a second pin disposed adjacent a bottom edge of the door panel, the first and second pins allowing for the pivoting movement between the door panel and the frame mount; and a first biasing component associated with frame mount and a second biasing component associated with the door panel, each of the first and second biasing components comprising a flat portion and a beveled portion. When the door panel is pivoted in the first direction by an angle less than the threshold angle, or is pivoted in the second direction by an angle less than the threshold angle, the bias of the door panel toward the closed position is caused the weight of the door causing the beveled portions of the first and second biasing components to slide with respect to each other, and when the door panel is pivoted in the first direction by an angle greater than or equal to the threshold angle, or is pivoted in the second direction by an angle greater than or equal to the threshold angle, the flat portions of the first and second biasing components engage one another such that the door panel is no longer biased toward the closed position due to cooperation of the beveled portions of the first and second biasing components.
In some embodiments, a top edge of the door panel is defined by a continuous curve along an entire length thereof. In certain of these embodiments, the curve of the top edge of the door panel has a varying radius of curvature that increases from an end adjacent to the frame mount to an end opposite to the frame mount. In some embodiments, a bottom edge of the door panel is defined by a continuous curve along an entire length thereof. In certain of these embodiments, the curve of the bottom edge of the door panel has a varying radius of curvature that increases from an end adjacent to the frame mount to an end opposite to the frame mount.
In some embodiments, the door panel is formed from a material comprising polycarbonate. In some embodiments, the door panel is formed from a material comprising polyester.
In accordance with another aspect of the present invention, a ligature resistant flexible swinging door assembly comprises a frame mount, a flexible door panel, and a pivot assembly operably connecting the door panel to the frame mount such that the door panel is pivotable in a first direction from a closed position to a first opened position and is pivotable in a second direction, opposite to the first direction, from the closed position to a second opened position. The door panel is formed from a flexible polymeric material having a modulus of elasticity between 250 and 470 ksi (1.79 and 3.24 GPa), a flexural yield strength between 5220 and 15000 psi (36 and 103 MPa), a flexural modulus between 141 and 450 ksi (0.971 to 3.10 GPa) and a flexural strain at yield between 7.00% and 7.20%. The door panel is formed from a material comprising at least one of polycarbonate and polyester, has a thickness of between 0.1094 and 0.1563 inches (2.78-3.97 mm), and has a width of between 32 and 36 inches (81.3-91.4 cm), whereby the swinging door assembly is adapted to be installed in a door opening having a width of about 36 inches (about 91.4 cm).
In some embodiments, the door panel has a thickness of about 0.1250 inches (about 3.18 mm). In some embodiments, the door panel has a thickness of about 0.1181 inches (about 3.0 mm). In some embodiments, the door panel has a width of about 34 inches (about 86.4 cm).
In some embodiments, a top edge of the door panel is defined by a continuous curve along an entire length thereof. In certain of these embodiments, the curve of the top edge of the door panel has a varying radius of curvature that increases from an end adjacent to the frame mount to an end opposite to the frame mount. In some embodiments, a bottom edge of the door panel is defined by a continuous curve along an entire length thereof. In certain of these embodiments, the curve of the bottom edge of the door panel has a varying radius of curvature that increases from an end adjacent to the frame mount to an end opposite to the frame mount.
In accordance with a further aspect of the intention, a flexible door panel adapted for use in connection with a ligature resistant flexible swinging door assembly comprises a top edge defined by a continuous curve along an entire length thereof and a bottom edge defined by a continuous curve along an entire length thereof. The door panel is formed from a flexible polymeric material having a modulus of elasticity between 250 and 470 ksi (1.79 and 3.24 GPa), a flexural yield strength between 5220 and 15000 psi (36 and 103 MPa), a flexural modulus between 141 and 450 ksi (0.971 to 3.10 GPa) and a flexural strain at yield between 7.00% and 7.20%. More specifically, the door panel is formed from a material comprising at least one of polycarbonate and polyester, has a thickness of between 0.1094 and 0.1563 inches (2.78-3.97 mm), and has a width of between 32 and 36 inches (81.3-91.4 cm), whereby the door panel is adapted to be installed in a door opening having a width of about 36 inches (about 91.4 cm).
In some embodiments, the door panel has a thickness of about 0.1250 inches (about 3.18 mm). In some embodiments, the door panel has a thickness of about 0.1181 inches (about 3.0 mm). In some embodiments, the door panel has a width of about 34 inches (about 86.4 cm).
In some embodiments, the curve of the top edge of the door panel has a varying radius of curvature. In certain of these embodiments, the curve of the bottom edge of the door panel has a varying radius of curvature.
Other objects of the invention and its particular features and advantages will become more apparent from consideration of the following drawings and accompanying detailed description.
Generally, the present invention provides a swinging door system of the type often found on bathroom stalls and the like that allows for the door to operate in much the same way that traditional swinging doors operate (particularly, allowing for privacy), while at the same time obviating at least some of the traditional ligature anchor points (including the gap between the free edge of the door panel and the corresponding edge of the door opening when the door is in the closed position), that allows the door to easily swing in both directions, but to be biased toward a closed position (at least in certain positions), without the need for springs or similar possible ligature points and that is both aesthetically pleasing and that can be retrofit to existing doorways (such as existing patient bathroom doorways), to facilitate the updating of existing facilities
Exemplary embodiments of the present invention will now be described with reference to the drawings.
Referring first to
The swinging door assembly (10) is disposed in a door opening (18), which may be of substantially any known type. For example, the door opening could take the form of an opening provided in a wall (with or without a door frame), the door opening could be formed by frame elements and/or panels (such as the case with bathroom stalls), etc. The frame mount (12) is rigidly affixed to one side of the door opening (18) by screws, bolts or the like, as is commonly known.
The door panel (14) and the door opening (18) are sized such that when in the door is in the closed position (shown in
Similarly, the swinging door assembly (10) of the present invention could be used with door opening having any of various heights. Similar to the above with respect to the gap provided on the side of the door panel (14), it is preferable, though not required, for there to be provided gaps above and below the door panel (14), again to obviate potential ligature anchor points. On the other hand, of course, the gaps should not be so large that privacy is impeded. In the example shown, the height (H) of the overall swinging door assembly (10) is 72 inches, while the height (B) of the gap between the door panel (14) and the floor of the door opening (18) is 10 inches.
As can be seen, the gap between the top of the door panel (14) and the top of the door opening (18) is irregular in shape due to the fact that the top edge (20) of the door panel (14) is irregular in shape. As will be recognized, if the top edge (20) of the door panel (14) was horizontal, or included a portion that was horizontal, ligatures may be looped over the top of the door panel (14), thereby providing an undesirable ligature anchor point. Thus, the top edge (20) of the door panel is preferably inclined and/or curved, such that any ligature looped over the top of the door would slide down and off the door panel (14) if weight was applied thereto. In the embodiment of
While a straight, or partially straight, top edge (20), with a sufficient incline with respect to horizontal, may provide adequate results depending on the situation, it has been found that configuring the top edge (120) of the door panel (114) as a continuous curve along an entire length thereof provides significantly improved results, both from anti-ligature and aesthetic standpoints. A door panel (114) having a top edge (120) configured as such is shown specifically in
It is also preferred that the top edge (120) of the door panel (114) has a rounded and/or bull-nose configuration along its thickness so as to further promote the sliding down and off the door panel (114) any ligature looped over the top of the door if weight was applied thereto. A rounded and/or bull-nose configuration may also provide enhanced aesthetic appeal.
As is shown in
It should be recognized that in addition to reducing the ability of the bottom edge (121) of the door panel (114) to be used as a ligature anchor point, configuring the bottom edge (121) of the door panel (114) as a continuous curve along an entire length thereof as shown in
As with the top edge (120), it is also preferred that the bottom edge (121) of the door panel (114) has a rounded and/or bull-nose configuration along its thickness so as to further promote the sliding down and off the door panel (114) any ligature looped under the door if weight was applied thereto. A rounded and/or bull-nose configuration may also provide enhanced aesthetic appeal.
The door panel (14) may be provided with any of various finishes to enhance the aesthetic appeal of the swinging door assembly (10). For example, the door panel (14) may be clear, colored (e.g., black), frosted, mirrored, tinted, finished as simulated wood, or as required otherwise. Preferably, the material and finish provide a relatively low coefficient of friction, at least along the top edge (20) of the door panel (14) to further enhance the slipping of potential ligatures off the door panel (14) if weight is applied thereto. If desired, the material and finish may demonstrate relatively low static or anti-static properties.
If desired, the swinging door assembly (10) may optionally be provided with a ligature resistant privacy element (22), but otherwise preferably features no exposed hardware, aligning with modern interior design initiatives. For example, the ligature resistant privacy element (22) may take the form of a crescent pull and/or a ligature resistant thumb turn or the like (such as disclosed in U.S. Pat. No. 8,584,494, for example). Again, however, such is not necessary for operation of the swinging door assembly (10), as discussed more fully below.
Turning now to
When the door panel (14) is pivoted in the first direction (D1) by an angle less than a threshold angle (αT), or is pivoted in the second direction (D2) by an angle less than the threshold angle (αT), the door panel (14) is biased toward the closed position by virtue of a weight of the door panel (14), as more fully described below. On the other hand, when the door panel (14) is pivoted in the first direction (D1) by an angle greater than or equal to the threshold angle (αT) such that it reaches a first threshold position (T1) (illustrated by dashed lines), or is pivoted in the second direction (D2) by an angle greater than or equal to the threshold angle (αT) such that it reaches a second threshold position (T2) (illustrated by dashed lines), the door panel (14) is no longer biased toward the closed position, but instead will remain in its then current position absent some external force being applied thereto, also as more fully described below.
Preferably, though not necessarily, the first opened position (O1) is defined by the door panel (14) being pivoted in the first direction (D1) by an angle (αO) of about 90° with respect to the closed position, and the second opened position (O2) is defined by the door panel (14) being pivoted in the second direction (D2) by an angle (αO) of about 90° with respect to the closed position.
It has been found that excellent results are achieved when the threshold angle (αT) is about 60°. However, this particular angle may be easily modified, if desired, as discussed below.
Turning now to
In general, the pivot assembly includes a first pin (30) disposed adjacent the top edge of the door panel (14) and a second pin (32) disposed adjacent a bottom edge of the door panel (14), the pins (30, 32) cooperating with corresponding sleeves (34, 36) provided as part of the frame mount (12). For this purpose, each of the sleeves is provided with a recess (38, 40) (best seen in
Although two pins (30, 32) are discussed, as best seen in
As best seen in
Referring now specifically to
The selective bias (the functional operation of which is discussed above in connection with
The first biasing component (50) associated with the frame mount (12), which is best seen in
As best seen in
Referring now to
Like the first biasing component (50), the second biasing component (52) also comprises a flat portion (60) and a beveled portion (62) angled with respect to the flat portion (60) at one end thereof. In the illustrated exemplary embodiment, the beveled portion (62) of the second biasing component (52) is inclined with respect to the flat portion (60) thereof by an angle of about 45° in order to complement the configuration of the flat portion (56) and the beveled portion (58) of the first biasing component (50).
It should be noted, however, that the particular configuration illustrated—i.e., the angle between the flat portions (56, 60) and the beveled portions (58, 62) of the first and second biasing components (50, 52), as well as the illustrated size of the flat portions (56, 60) of the first and second biasing components (50, 52)—is what leads to the exemplary threshold angle (αT) discussed above of about 60°. However, it should be recognized that by modifying the angle between the flat portions (56, 60) and the beveled portions (58, 62) of the first and second biasing components (50, 52), and/or by varying the illustrated size of the flat portions (56, 60) of the first and second biasing components (50, 52), the threshold angle (αT) may also be modified.
Turning now to
When the door panel (14) is pivoted in the first direction by an angle less than the threshold angle (αT), or is pivoted in the second direction by an angle less than the threshold angle (αT), a bias is created on the door panel (14) toward the closed position (shown in
On the other hand, when the door panel (14) is pivoted in the first direction by an angle greater than or equal to the threshold angle (αT), or is pivoted in the second direction by an angle greater than or equal to the threshold angle (αT), the flat portions (56, 60) of the first and second biasing components (50, 52), respectively, engage one another such that the door panel (14) is no longer biased toward the closed position due to cooperation of the beveled portions (58, 62) of the first and second biasing components (50, 52). Instead, once the threshold angle (αT) is reached in either direction, and up until the fully open angle is reached in either direction (αO), the flat portions (56, 60) of the first and second biasing components (50, 52), both being generally horizontal (i.e., perpendicular with respect to the force of gravity), merely slide with respect to one another.
The friction created between the flat portions (56, 60) of the first and second biasing components (50, 52) due to the weight of the door panel (14) will cause the door panel (14) to be urged to maintain its then current position between the threshold position (T1, T2) and the respective fully open position (O1, O2) in either direction. However, the amount of said friction being relatively small, the door panel (14) can be freely swung further open (if not already fully opened) or back toward the closed position, such that once the angle of the door panel (14) is less than the threshold angle (αT) in either direction, the door panel (14) will again be biased toward the closed position.
As will be noted by comparing
In order to accommodate the above-described vertical movement of the door panel (14), including the first and second pins (30, 32), the first and second pins (30, 32) are axially slideable within sleeves (34, 36). In particular, the sleeves (34, 36) are dimensioned so as to provide sufficient room at the tops/bottoms of the recesses (38, 40) in order to accommodate the necessary amount of axial movement of the door panel (14) with respect to the frame mount (12) as the beveled portions (58, 62) of the first and second biasing components (50, 52) slide with respect to each other.
Turning now to
It would be much more desirable if the door panel (14) was made of a flexible material, such that it would not be possible for a ligature (200) positioned as shown in
Of course, it must be recognized that the door panel (14) should not be so flexible that it's functioning as a door panel is impeded. For example, if the door panel (14) is too flexible, it may deform under its own weight (particularly over time), such that the privacy function of the door is impacted.
We have discovered that in order to achieve the optimum confirmation, a number of considerations must be taken into account, including, but not limited to, the material from which the door panel (14) is formed, the width of the door panel (14)—as dictated by the width of the door opening (18) and the thickness of the door panel (14). Each of these considerations, and the cooperation thereof, impacts the behavior of the door panel (14) both in everyday use, and when/if an attempt is made to use the door panel (14) as a ligature anchor point.
In a broadest sense, optimum results have been found to be produced when the following conditions are met:
It has even more specifically been found that excellent results were achieved when the door panel is formed from a material including polycarbonate and/or polyester, with polycarbonate being the most preferred given the dimensional and environmental considerations discussed herein.
It should be recognized that materials having the above-discussed properties, and even the specific exemplary materials themselves, may have previously been used in connection with door panels. However, if such was the case, conventional wisdom would dictate that the thickness and width of the door panel be selected so as to prevent flexing (i.e., so as to be rigid) in all cases, which is exactly the opposite of our invention.
With respect to a thickness of the door, while thicknesses of between 0.040 and 0.315 inches (1.0-8.0 mm) have been found to provide excellent results, it is more preferred for the thickness to be between 0.0625 and 0.250 inches (1.6-6.35 mm), it is even more preferred for the thickness to be between 0.0938 and 0.1875 inches (2.38-4.76 mm), and it is most preferred for the thickness to be between 0.1094 and 0.1563 inches (2.78-3.97 mm). Specific examples providing excellent results were achieved using materials having a standard thickness of about 0.1250 inches (about 3.18 mm) or about 3.0 mm (about 0.1181 inches).
These thicknesses have been found to be appropriate, as noted above, in connection with door panels having a width of between 26 and 42 inches (66.0-106.7 cm). More particularly, the above-discussed thicknesses have been found to provide excellent results when used in connection with swinging door assemblies used in connection with a standard sized nominal door opening of about 30 inches (about 76.2 cm). In such situations, the door panel (14) may have a width of between 26 and 30 inches (66.0-76.2 cm), most typically about 28 inches (about 71.1 cm) in order to accommodate the frame mount (12), the pivot assembly (16) and the gap (A). As another preferred example, the above-discussed thicknesses have been found to also provide excellent results when used in connection with swinging door assemblies used in connection with a standard sized nominal door opening of about 36 inches (about 91.4 cm). In such situations, the door panel (14) may have a width of between 32 and 36 inches (81.3-91.4 cm), most typically about 34 inches (about 86.4 cm) in order to accommodate the frame mount (12), the pivot assembly (16) and the gap (A).
In a very specific example of a preferred exemplary embodiment, the door panel (14) has a standard thickness of about 0.1250 inches (about 3.18 mm) or about 3.0 mm (about 0.1181 inches) and has a width of about 34 inches (about 86.4 cm), such that the swinging door assembly is adapted to be installed in a door opening having a width of about 36 inches (about 91.4 cm).
The present invention thus provides door hardware that allows for a swinging door to operate in much the same way that traditional swinging doors operate (particularly, allowing for privacy and security), while at the same time obviating at least some of the traditional ligature anchor points.
