sofa bed

A sofa bed or sofa-bed (in the US often called a sofabed, hide-a-bed, bed-couch, sleeper-sofa, or pullout sofa) is a multifunctional furniture typically consisting of a sofa or couch that, underneath its seating cushions, hides a metal frame and thin mattress that can be unfolded or opened up to make a bed. A western-style futon differs from a sofa bed, although sofa beds using futon mattresses are common.

The far more portable camp bed is much older.

History

Leonard C. Bailey took out a patent for making the first "folding bed" on 18 July 1899. The metal bed frame was capable of being folded, bent mattress closed for use if needed. Later, it was known as a "hide-a-bed".

Rudolf Coopersmith filed a patent for the Davenport bed in 1905. Between 1905 and 1947 Coopersmith filed over 30 patents for mechanical parts of sofa beds, mattresses and mattress manufacturing machinery. In 1925 he took out a patent for the sofa bed, the precursor of the modern day pull out sofa.

William Lawrence Murphy took out a patent for making "In-A-Dor bed", which is known as a "Murphy bed" today. It is characterized by the folded space-saver into a wall closet.

In 1931, Bernard Castro made and sold the "Castro convertible" by using $400 from his savings. Castro’s design is considered to be the evolution of most sofa beds sold nowadays.

After mimicking the Japanese founders, the futon appeared in the United States around 1980. William Brouwer is the person who evolved the first sofa convertible frame style in the United States.

A "slide away bed" can refer to a type of sofa bed that slides to the wall to form a sofa, with the mattress hinged to form a seating surface and back support. The bed frame support is a telescoping frame that allows the bed platform to recess below the seating cushion. The primitive version of the Slide Away Bed was invented by Manning Lane, Warren J. Hauck and Roy O. Sweeney of Cincinnati, Ohio. The knock-down sofa bed with hinged mattress patent was filed on September 5, 1978, and issued on May 27, 1980.US Patent for Knock-down sofa bed with hinged mattress Patent (Patent # 4,204,287 issued May 27, 1980) - Justia Patents Search
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Mattress types

Although most sofa beds use a queen short mattress measuring , other common sizes include , , and . The average sofa bed mattress thickness is , thus being half as thick as a good standard mattress. Sofa mattresses can be produced out of many different materials, the majority on the market being made of springs or foam.

Spring sofa mattress

Although springs can make a satisfactory sofa bed mattress, the following aspects have to be considered regarding a spring sofa mattress:
* ''Free length'' represents the overall length of a spring when no load is applied.
* ''Solid height'' is the length of a compression, when the spring has been deflected enough to allow each adjacent coil to touch each other.
* ''Working length'' represents the difference between the free length and the solid height.
* ''Active coils'' is the number of coils that are free to deflect under load, i.e. the total number of coils minus the number of closed coils forming the ends is a measure of the spring quality. The more active coils a mattress has, the less working length it has, which means that the springs are the less likely to deteriorate.
* ''Hydrogen embrittlement'' represents the hydrogen absorbed in electroplating of carbon steels causing the spring material to become brittle, leading to cracking and spring failure. Plated springs are a problem, and unplated springs are more likely to rust. Plastic coating is an alternative, but is extremely expensive.
* The best springs are ''stress relieved'', which means that the springs were treated at a temperature so as to relieve stresses. Not going through such a procedure might cause mattress failure. Unfortunately, many mattress springs are not stress relieved because it is expensive.

Foam sofa mattress

Quality foam sofa bed mattresses compress as needed, the foam acting like an infinite number of springs. A high quality foam gives better support, molds to the body and snaps back to shape. Consider the following factors of a high quality sofa bed mattress:
* Density is a measurement of the kilograms (or pounds) of polyurethane foam per cubic meter (or cubic foot). High density foams can be made very soft, whereas low density foams can be made very firm.
* Indentation force deflection (IFD) is the measure of the foam’s support, representing the Newtons (or pounds of force) required to indent a foam sample by a specified percentage of its original thickness. Support is the foam’s ability to "push back" against your body weight, and prevent the foam from "bottoming out" on the frame or base.
* Foam durability, flex fatigue and compression set are other terms related to foam performance.

Pocket-coil mattress

Pocket-coil mattresses are generally higher in quality than spring or foam mattresses. Each coil is encased in its own pocket, allowing the mattress to keep its shape over time while also providing more sleep support. Pocket-coil mattresses are thicker than standard sofa bed mattresses, starting from and going up to for a premium product. The high-quality support provided eliminates the need for extra cushioning, allowing the mattress to become the seat of the sofa. This has resulted in a new style of sofa bed that does not require its mattress to be folded up and tucked inside.

Slide-away bed

A slide away bed' is a brand of sofa bed that slides to the wall to form a sofa. The mattress is hinged to form a seating surface and back support. The bed frame support is a telescoping frame that allows the bed platform to recess below the seating cushion.

History

The primitive version of the Slide Away Bed was invented by Manning Lane, Warren J. Hauck and Roy O. Sweeney of Cincinnati, Ohio.

See also

* Bunk bed
* Murphy bed
* Slide away bed
* Trundle bed

References

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Beds
Couches
Space-saving furniture