Tool set for tucking bedsheets

Abstract

The bedsheet-tucking tool kit consists of at least one bed-mattress lifter and at least one bedsheet tucker. The lifter has a handle and an insertable portion, the distal end of which tapers in the direction away from the handle. A stopper provided between the handle and the tapered portion limits insertion of the lifter to a position in which the bedsheet can fall behind the inserted portion. At its bottom, the lifter has a flared wing-like portion that maintains stability of the lifter in the inserted position. In order to increase friction between the bottom of the lifter and the boxspring mattress, a small portion of the bottom surface of the lifter is coated with a thin rubber-like coating. This protects the lifter from popping out from the inserted position. The handle may be coated with a rubber film. The tucking tool is made in the form of a spade with a rounded knob-like handle and a flat tucker blade.

Description

FIELD OF THE INVENTION

The present invention relates to the field of making beds, in particular to a set of tools for tucking bedsheets and blankets between a boxspring mattress and a bed mattress.

BACKGROUND OF THE INVENTION

Bedmaking can be a physically intensive task that is completed at home as well as in various industries, including hotel and healthcare industries. In these industries, bedmaking is a compulsory and a labor-consuming operation that often results in increased strain to the low back and upper extremities. The proposed tool set for tucking a bedsheet reduces the physical risk factors associated with making beds by reducing awkward posture of the spine, wrist, and shoulders. Use of this tool set also eliminates the lifting force required to raise the mattress in order to tuck in a bedsheet, replacing the lifting with a simple push/insertion of a tool. Eliminating the need to lift a mattress significantly reduces overall risk to a variety of musculoskeletal disorders.

If a bed consists of a boxspring mattress and a bed mattress, the conventional bedmaking procedure consists of the following operations. First, a bottom bedsheet is placed on the bed and is tucked between the boxspring mattress and the bed mattress. Tucking the bottom bedsheet requires lifting the bed mattress high enough to place one's hand between the boxspring mattress and the bed mattress. Next, the top bedsheet and blanket, or blankets, are placed on the mattress. Finally, the top bedsheet and blanket, or blankets, are tucked between the boxspring mattress and the bed mattress. The increase in amount of material to be tucked between the boxspring mattress and the bed mattress requires increased lifting of the bed mattress, thereby requiring increased pushing force to maneuver the material between the boxspring mattress and the bed mattress. The material on the corners is typically folded and then tucked.

Thus, it can be seen that the tucking of bedsheets and blankets takes a significant amount of time and physical effort in the bedmaking process and, to a great extent, defines the quality of the entire bedmaking process.

Moreover, if only one person is making a bed, the sequence of lifting the bed mattress and tucking the bedsheet and blankets must be repeated several times around the perimeter of the bed.

So far these operations have been and still are performed manually.

An attempt has been made to mechanize the bedsheet/cover-tucking operation by means of special tools. U.S. Pat. No. 4,745,650 issued in 1988 to F. Elliott describes a method of burping [this couldn't be correct] a water mattress and a tool for tucking a bedsheet between said water mattress and surrounding frame. The tool is flat and rectangular and is made of a self-lubricating plastic material approximately ¼ inch in thickness and with rounded edges to prevent damage to the mattress. First, the corners of the bedsheet are inserted under the bed mattress, and then the tool is used in a sliding motion along the edge of the mattress, thereby tucking the bedsheet under the bed mattress.

Also known in the art is a number of U.S. Patent Application Publications, i.e., No. 20080235878 published in 2008 (inventors: Carisa Harris-Adamson, et al); No. 20080052836 published in 2008 (inventors: Carisa Harris-Adamson, et al); No. 20080040859 published in 2008 (inventors: Carisa Harris-Adamson, et al); No. 20080040858 published in 2008 (inventors: Elizabeth Sakaldasis, et al); and No. 20080040856 published in 2008 (inventors: Elizabeth Sakaldasis, et al). The inventions of these patent applications are similar and differ only in small details. One of these applications, i.e., Patent Application Publication No. 20080040858, was granted U.S. Pat. No. 7,398,569 issued in 2008 to E. Sakaldasis, et al, and is titled “Apparatus and methods for lifting bed mattresses and/or tucking in bed covers.” The invention discloses various embodiments of apparatus and methods for their use, which are designed to aid in lifting bed mattresses and tucking in bed covers. In general, the kit consists of a lifting tool in the form of a vertically oriented and raised wedge portion and a vertical handle with a space formed between the handle and the wedge portion. A horizontal flat and flared portion is formed on the bottom of the raised portion. In this context, the terms “vertical” and “horizontal” are used with reference to the position of the tool during insertion between the horizontally positioned boxspring mattress and the horizontally positioned bed mattress for the purpose of lifting the latter before tucking the edge of the bedsheet between the mattresses with use of the tucking tool. The tucking tool is made in the form of a flat spade that flares outward, i.e, in the direction away from the vertically positioned handle.

However, the kit containing the lift and tuck tools described above possesses a number of disadvantages. Because the handle is made in the shape of a vertical rod with a space between the handle and the raised wedge portion, the lifting tool is inserted too far between the boxspring mattress and the bed mattress so that the neighboring portions of the bedsheet fall down onto the handle and sometimes completely cover it, falling behind the lifting portion of the tool. This prevents the bedsheets from being properly tucked and causes them to pull out from under the mattress when the mattress lifter is removed. Additional lift-and-tuck motions are needed for raising the edges of the mattress and tucking the bed covers. Also, the wedge of the mattress lifter is too short, thereby decreasing the space between the boxspring mattress and the bed mattress and requiring extra lifting when blankets and covers are being tucked between the mattresses. The lifting capacity of the mattress lifter is insufficient to allow for placement of the tool on the side or end of the bed and for easier bedsheet tucking. Additionally, the platform on top of the wedge is too short for the mattress to rest on it. As a result, the tool often slides out from between the mattresses. The base of the tool is too narrow and often falls on its side during the bedsheet-tucking process. The bottom surface of the mattress lifter is very smooth and in some instances the tool slides out because of insufficient friction between the tool and the boxspring mattress. The solid handle is smooth, inconvenient to hold, and consumes a significant amount of material for manufacturing. The bedsheet tucker has a wide triangular blade with edges that are too angular, thereby causing tearing of the bedsheets. The cylindrical handle of the tucker is perpendicular to the surface of the blade, and the neck connecting the blade with the handle is too long, requiring increased effort to control and to guide the tucker and creating unnecessary moment during insertion.

OBJECTS AND SUMMARY OF THE INVENTION

It is an object of the invention to eliminate the disadvantages of the prior art and to provide a kit of tools for lifting a bed mattress and for tucking a bedsheet between mattresses, wherein the bed-mattress lifting tool has a stopper between the gripping portion of the handle and the lifting portion of the tool in order to limit the amount of insertion of the lifter to a position in which the cover does not fall behind the lifting portion. It is another object to provide a mattress lifter of the aforementioned tool kit wherein the wedge of the tool is longer and taller than conventional types, and the platform on top of the wedge is longer than conventional types so that the mattress can rest on it. It is another object to make the base of the mattress lifter wide enough to reduce resistance and to stabilize the mattress lifter during insertion between mattresses. It is a further object to coat part of the lower surface of the mattress lifter with a friction coating to prevent the mattress lifter from popping out. It is a further object to increase the lifting capacity of the mattress-lifting tool in order to facilitate the tucking operation with the tucking tool and for allowing placement of the mattress lifter on the side or end of the bed without requiring placement close to the corner. It is another object to shorten the neck of the tucker blade and to eliminate perpendicularity of the tucker handle. It is a further object to round the edges on the ends of the tucker blade to eliminate tearing of bedsheets. It is another object to change the vertical handle of the tucker to a smaller knob-like handle that can be used safely in a squatting or standing position. It is another object of the invention to provide a new and efficient method of tucking the cover/bedsheet between two mattresses by lifting the bed mattress simultaneously with several lifters and then tucking the cover/bedsheet between the mattresses sequentially with a single tucking tool without resorting to multiple mattress-lifting operations.

In general, the bed-tucking tool kit of the present invention consists of at least one mattress lifter and at least one bedsheet tucker. The mattress lifter (hereinafter referred to as the “lifter”) is preferably a hollow plastic body molded from two halves connected to each other side by side. The lifter has a proximal end, which is located on the side of the user, and a distal end, which is on the side of the bed. The lifter consists essentially of two non-parallel parts, one of which is an insertable portion, the distal end of which is intended for insertion between the boxspring mattress and the top bed mattress, and the other is a handle that is formed on the proximal end of the lifter. The insertable portion comprises a vertically arranged plate of predetermined thickness, which is wide enough for the mattress to rest upon it. The plate-like insertable portion, which is located closer to the handle, has its top surface parallel to the bottom of the lifter, while the distal end of the vertically arranged plate tapers downward toward the tip of the plate. The intermediate part of the vertically arranged plate is provided with a flared portion that is located below the aforementioned top surface, the latter of which is parallel to the bottom and is arranged horizontally and in flush with the lower surface of the lifter. The flared portion is made in the form of two symmetrical wings that extend radially outward from the vertical plate and widening in a tapered manner toward the proximal end. An essential feature of the lifter that distinguishes it from the similar tool of the prior art is the provision of a stopper between the handle and the insertable portion of the vertical plate. The purpose of the stopper is to limit the extent of insertion of the lifter to a position in which the bedsheet can fall behind the lifting portion. The stopper can be made integrally with the gripping portion of the handle and is connected to it by a horizontal cross bar to form a closed configuration with an opening for the user's hand. In order to increase friction between the bottom of the lifter and the boxspring mattress, a small portion of the bottom surface of the lifter can be coated with a thin rubber-like coating. This protects the lifter from popping out from the inserted position. The vertical plate portion is high enough to provide a lifting capacity sufficient for unobstructed insertion of the tucking tool. The latter comprises a substantially spherical or otherwise rounded knob-like handle and flat tucker blade that is connected to the handle by a narrow neck and that widens in the direction away from the handle. The corners on the wide distal end of the triangular tucker blade are rounded. The invention also covers a new method of tucking a cover/bedsheet between two mattresses by lifting the bed mattress simultaneously with several lifters and then tucking the cover/bedsheet between the mattresses with a single tucking tool, thereby eliminating multiple mattress-lifting operations.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a three-dimensional view of the bed-tucking tool kit of the present invention consisting of a mattress-lifting tool and a bedsheet tucking tool.

FIG. 2 is a side view of the lifter of FIG. 1 in the direction of arrow A.

FIG. 3 is a top view of the lifter of FIG. 1 in the direction of arrow B in FIG. 2.

FIG. 4 is a three-dimensional view of the lifter of FIG. 1 in the position of insertion between a boxspring mattress and a bed mattress (the bedsheet is not shown).

FIG. 5 is a side view of the tucking tool of FIG. 1 in the direction of arrow C.

FIG. 6 is similar to FIG. 4 but shows the bedsheet and cover or blanket that is to be tucked/secured between the boxspring mattress and the bed mattress.

FIG. 7 is a top view of the bed with a plurality of lifters inserted into working positions for tucking the bedsheet with a single tucking tool, thereby eliminating multiple lifting of the bed mattress.

DETAILED DESCRIPTION OF THE INVENTION

As shown in FIG. 1, which is a three-dimensional view of a bed tucking tool kit of the present invention, the kit, which is designated by reference numeral 20, consists of at least one mattress lifter 22 and at least one bedsheet tucker 24.

Let us first consider the mattress lifter 22 (hereinafter referred to as “lifter”). FIG. 2 is a-side view of the lifter 22 in the direction of arrow A in FIG. 1, FIG. 3 is a top view of the lifter 22 in the direction of arrow B in FIG. 2, and FIG. 4 is a three-dimensional view of the lifter 22 inserted into the interface F between a boxspring mattress M1 and a bed mattress M2 (the bedsheet is not shown in FIG. 4).

Preferably, the lifter 22 is a hollow plastic body molded from two halves 22a and 22b connected, e.g., glued or thermally bonded, to each other side by side along a split line 22c (FIG. 1). The lifter 22 has a proximal end 26, which is located on the side of the user (not shown), and a distal end 28 (FIG. 1), which is on the side of the bed (FIG. 4).

The lifter consists essentially of two non-parallel parts, one of which is an insertable portion 30 (FIGS. 2 and 3), the distal end 28 of which is intended for inserting into the interface F between the boxspring mattress and the bed mattress (FIG. 4), and the other is a handle 32, which is formed on the proximal end 26 of the lifter 22. The insertable portion 30 comprises a vertically arranged plate 34 (FIG. 2) of predetermined thickness, which is wide enough for the bed mattress M2 to rest upon it.

The plate-like insertable portion 30, which is located closer to the handle 32, has its top surface 30a parallel to the bottom 36 (FIG. 2) of the lifter 22, while the distal end 28 of the vertically arranged plate 34 has a tapered portion 30b inclined downward toward the tip 30c (FIGS. 2 and 3) of the plate 34. The intermediate part of the vertically arrange plate 34 between the distal end 28 and the proximal end 26 (FIG. 2) is provided with a flared portion 38 (FIG. 3) formed at the bottom of the plate portion 34 flush with the lower surface 36 (FIG. 2) of the lifter 22. The flared portion 38 is made in the form of two symmetrical extending wings 38a and 38b extending radially outward from the vertical plate 34 and widening towards the proximal end 26 (FIG. 3).

An essential feature of the lifter 22 that distinguishes it from the similar tool of the prior art is the provision of a stopper 40 (FIGS. 1, 2, and 4) between the handle 32 and the insertable portion 30 of the vertical plate 34. The purpose of the stopper 40 is to limit the extent of insertion of the lifter 22 to a position in which the bedsheet (not shown in FIGS. 1 to 4) may fall behind the insertable portion 30.

The stopper 40 can be made integrally with the handle 32 and is connected to it by a horizontal cross bar 42 to form a closed configuration with an opening 43 for the user's hand (FIGS. 1, 2, and 4). In order to increase friction between the bottom 36 of the lifter 22 and the boxspring mattress M1 (FIG. 4), a small portion of the bottom surface of the lifter can be coated with a thin rubber-like coating 44. This protects the lifter 22 from popping out from the inserted position.

The vertical plate portion 34 is high enough to provide a lifting capacity sufficient for unobstructed insertion of the tucking tool 24 (FIG. 1) which will now be described in more detail. The tucking tool 24 is intended for tucking the edge of a bedsheet, cover, and/or blanket into the interface F between the mattresses M1 and M2 (FIG. 4). As mentioned above, the bedsheet, cover, and blanket are not shown in FIG. 4. The tucking tool 24 (FIG. 1) comprises a substantially spherical or otherwise rounded knob-like handle 46 and a flat and substantially triangular tucking blade 48 that is connected to the handle by a narrow neck 50 and widens in the direction away from the handle 46. The corners 52 and 54 on the wide side 56 of the triangular tucking blade 48 are rounded.

As shown in FIG. 5, which is a side view of the tucking tool 24 in the direction of arrow C in FIG. 1, the plane of the blade 48 passes approximately through the center O of the spherical handle 46. The handle is not necessarily spherical as shown in FIG. 1 but may have, e.g., an oval shape of the type shown in FIG. 5 and designated by reference numeral 46a, or any other configuration convenient for gripping and manipulation.

The operation associated with the use of the tool kit 20 shown in FIG. 1 will now be described with reference to FIG. 6, which is similar to FIG. 4 but shows the bedsheet, cover, or blanket 58 that is to be tucked/secured between the boxspring mattress M1 and the bed mattress M2. First, the descending ends of the bedsheet 58 are raised to expose the interface F between the mattresses M1 and M2; next, the user (not shown) grasps the handle 32, inserts the distal end 28 of the lifter 22 into the interface F between the mattresses, and pushes the lifter 22 forward until the stopper 40 contacts the sides of the mattresses M1 and M2 (FIG. 6). Since the pusher 22 has a sufficient vertical dimension, the upper mattress M2 is raised above the lower mattress M1 with formation of a gap G between both mattresses on the sides of the pusher 22. The length L of the insertable portion 30 and the width W of the pusher (FIG. 3) are sufficient for reliably supporting the upper mattress M2, while provision of the flared portion 38 maintains the pusher 22 in a stable position with vertical orientation of the plate-like portion 34. The friction coating 44 on the bottom of the lifter 22 (FIG. 2) prevents the lifter from recoiling in the backward direction. Following this, if necessary, a part of the bedsheet can be slightly shoved with one hand between the boxspring mattress M1 and the bed mattress M2, or the descending edge of the bedsheet 58 is tucked into the gap G formed between the mattresses M1 and M2 by the lifter 22 without preliminary guidance. In this step, the tucking blade 48 is moved forward until the knob-like handle 46 contacts the side surfaces of the mattresses M1 and M2. The above-described lifting and tucking operations are repeated at each corner of the bed until the corners of the bedsheet and blanket are tucked. Use of the tool kit 20 of the invention accelerates the process, improves operational conditions of the user, and allows for quick processing of a bed with only three to four raising-tucking steps within only 30 sec. to 1 min.

Dimensions of the tools in the tool kit 20 of the invention are as follows.

Overall length L (FIG. 2): 270 to 300 mm (as compared to 250 of the
                           conventional tool disclosed in U.S. Pat.
                           No. 7,398,569);
Length L1 of insertable    160 to 170 mm;
portion (FIG. 2):
Width W (FIG. 3):          27 to 35 mm (compared with 26 for the
                           conventional tool disclosed in U.S. Pat. No.
                           7,398,569);
Width W1 of flared         70 to 90 mm (compared with 65 for the
portion 38 (FIG. 3):       conventional tool disclosed in U.S. Pat. No.
                           7,398,569); and
Height H of lifting        65 to 90 mm (compared with 60 for thel
portion of lifter 22       conventiona tool disclosed in U.S. Pat. No.
(FIG. 2):                  7,398,569).
The width of the tucking tool from the neck to the end of the blade ranges from 20 to 180 mm.
The lifter 22 and the tucker 24 can be molded from various plastic materials such as polypropylene, or the like.

In addition to the above-described tools, the invention also relates to a new method of tucking the bedsheet into the interface between two mattresses by using the above-described tools. The method comprises the step of lifting the bed mattress in a plurality of points around the bed perimeter; and the step of tucking the bedsheet between the mattresses sequentially with a single tucking tool, thereby eliminating multiple mattress-lifting operations. This method is illustrated in FIG. 7, where reference numeral 60 designates a bed, and references numerals 62a, 62b, . . . 62n designate lifters of the type shown and described above, which are inserted into the interface F (FIG. 4) between mattresses prior to tucking the bedsheet, blanket, or any other mattress-covering item 64 by means of a singe tucker 66 into the gap G (FIG. 4) formed with mattresses M1 and M2 with the use of lifters. The number of lifters used in this operation may vary from two to five, or the like. It is understood that this number, as well as earlier-presented tool dimensions, are given only as an examples.

Thus, it has been shown that the present invention provides a mattress-lifting and bedsheet-tucking tool kit, wherein the mattress-lifting tool has a stopper portion between the gripping portion of the handle and the lifting portion of the tool for limiting the extent of insertion of the lifter to a position in which the cover does not fall behind the lifting portion. The lifter of the aforementioned tool is longer and taller than the conventional tool of this type. The platform on top of the wedge is longer so that the mattress can rest on it. The base of the lifter is wide enough to reduce resistance and to stabilize the lifter during insertion of the lifter between the mattresses. A part of the lower surface of the lifting tool is coated with a friction coating to prevent the lifter from popping out. The entire tool is monolithic with structural reinforcements and is molded with recesses for saving material, making the tool lighter and making the handle more convenient for gripping. The lifting capacity of the mattress-lifting tool is increased in order to facilitate the tucking operation with the tucking tool and for allowing placement of the lifter on the side or end of a bed without requiring placement close to the corner. The neck of the tucker blade is shortened, and the tucker handle is made coaxial with the blade plane. The edges on the ends of the tucker blade are rounded to facilitate insertion and to prevent tearing of bedsheets. The vertical handle of the tucker is replaced with a smaller knob-like handle that can be used safely in a squatting or standing position. The invention also provides a new and efficient method of tucking the bedsheet into the interface between two mattresses by lifting the bed mattress simultaneously with several lifters and then tucking the cover/bedsheet between the mattresses sequentially with a single tucking tool, thereby eliminating multiple mattress-lifting operations.

Although the invention has been shown and described with reference to specific examples, it is understood that these examples should not be construed as limiting the invention and that any changes and modifications can be made with regard to materials, shapes, and other features of the illustrated embodiments without departure from the scope of the patent claims. For example, the tools can be made from wood or metal, the stopper can be made in the form of a vertical rod or plate without connection with the gripping part of the handle, the body of the lifter may have through-holes in the plate-like portion for weight reduction, etc. The material to be tucked is not limited by the bedsheet and, may comprise a cover, a blanket, or the like.

Claims

1. A tool set for tucking bedsheets containing a mattress lifter and a tuck tool for tucking a flexible object into an interface between a first object and a second object, wherein the mattress lifter comprises an elongated body having a proximal end facing the side of the user and a distal end facing the flexible object, the mattress lifter having a handle on the proximal end, a tapered portion on the distal end, and a stopper in an intermediate position between the lifter handle and the tapered portion to limit the length of insertion of the tapered portion into the interface between the first object and the second object in order to expose the interface and prevent covering thereof with the flexible object, and wherein the tuck tool comprises a handle with a triangular blade that widens in the direction away from the tucker handle.

2. The kit of claim 1, wherein the mattress lifter comprises a flat body that has a top surface and a bottom surface, a width, and a length, and is further provided with a flared portion that is flush with the bottom surface in the form of symmetrical wings having a triangular shape tapering toward the distal end of the mattress lifter.

3. The kit of claim 1, wherein the handle of the mattress lifter and the stopper are connected with a cross bar to form a closed configuration with an opening for the user's hand.

4. The kit of claim 1, wherein the first object is a boxspring mattress, the second object is a bed mattress, and the flexible material is selected from a bedsheet or blanket.

5. The kit of claim 2, wherein the first object is a boxspring mattress, the second object is a bed mattress, and the flexible material is selected from a bedsheet or blanket.

6. The kit of claim 3, wherein the first object is a boxspring mattress, the second object is a bed mattress, and the flexible material is selected from a bedsheet or blanket.

7. The kit of claim 1, wherein the triangular blade of the tuck tool has rounded corners on the distal end.

8. The kit of claim 2, wherein the triangular blade of the tuck tool has rounded corners on the distal end.

9. The kit of claim 6, wherein the triangular blade of the tuck tool has rounded corners on the distal end.

10. The kit of claim 7, wherein the handle of the tuck tool is coaxial with the triangular blade of the tuck tool.

11. The kit of claim 8, wherein the handle of the tuck tool is coaxial with the triangular blade of the tuck tool.

12. The kit of claim 9, wherein the handle of the tuck tool is coaxial with the triangular blade of the tuck tool.

13. The kit of claim 2, wherein at least a part of the bottom surface of the mattress lifter is coated with a friction coating.

14. The kit of claim 6, wherein at least a part of the bottom surface of the mattress lifter is coated with a friction coating.

15. The kit of claim 8, wherein at least a part of the bottom surface of the mattress lifter is coated with a friction coating.

16. The kit of claim 1, wherein the width of the mattress lifter ranges from 27 to 35 mm, and the length of the distal end of the tuck tool to the stopper ranges from 160 to 170 mm.

17. The kit of claim 16, wherein the width of the flared portion ranges from 70 to 90 mm.

18. The kit of claim 6, wherein the width of the mattress lifter ranges from 27 to 35 mm, and the length of the distal end of the tuck tool to the stopper ranges from 160 to 170 mm.

19. The kit of claim 9, wherein the width of the flared portion ranges from 70 to 90 mm.

20. The kit of claim 1, wherein the width of the mattress lifter ranges from 27 to 35 mm, and the length of the distal end of the tuck tool to the stopper ranges from 160 to 170 mm.

21. The kit of claim 1, wherein the shape of the tuck tool handle is spherical, oval, or elliptical.

22. The kit of claim 1, wherein the width of the tuck tool from the neck to the end of the blade ranges from 20 to 180 mm.

23. The kit of claim 10, wherein the width of the tuck tool from the neck to the end of the blade ranges from 20 to 180 mm.

24. The kit of claim 6, wherein the handle is coated with a rubber layer.

25. A method of tucking the cover/bedsheet into the interface between a first mattress and second mattress supported by a bed in which the second mattress supports the first mattress, the bed having a perimeter, comprising the following steps: providing a plurality of mattress lifters, each comprising an elongated body having a tapered distal end insertable into the interface between two mattresses, and at least one tuck tool comprising a handle and tucking blade widening in the direction away from the handle;lifting the first mattress in a plurality of points around the bed perimeter by means of a plurality of mattress lifters; andtucking the cover/bedsheet between the first mattress and the second mattress sequentially with said at least one tucking tool and around the bed perimeter.