Innerspring mattress with plastic foam cover

3,200,418

COVER

Sheets-Sheet 1

Aug. 17, 1965 _w LEBENS

INNERSPRING MATTRESS WITH PLASTIC FOAM Filed Nev. 2, 1961

<img file="US3200418A_D0001.tif" />

<img file="US3200418A_D0002.tif" />

Aug. 17, 1965

W. LEBENS

3,200,418

INNERSPRING MATTRESS WITH PLASTIC FOAM COVER

Filed Nov. 2, 1961

Sheets-Sheet 2

<img file="US3200418A_D0003.tif" />

<img file="US3200418A_D0004.tif" />

INVENTOR.

3,200,418

Patented Aug. 17, 1965

United States Patent Office ing the innerspring mattress structure of known construction, on both sides of which a thin intermediate layer 2 of rubberized fibrous material, such as animal hair, coir fiber, palm fiber, sisal fiber is positioned which is fur5 ther covered with a layer 5, 5 of resilient .foam material, such as plastic foam. The width of the overlapping edges of plastic foam sheet 5 is substantially equal on all sides. The angular Slot provided at each corner of the foam sheet 5 will form after bending the respective over70 lapping edges an even corner of the mattress.

The slightly overlapping edges of intermediate layer 2 are bent under the spring frame 3, as shown in FIG. 2, and held in position by clips 4. As the upholstering of the innerspring structure is carried out on both sides, it j 5 -gives an obvious way for a mattress of both-sided use. When 'intermediate layer is in position, it is comparatively an easy operation to glue plastic foam sheets ‘5, 5 to said layer thereby maintaining foam sheet 5 in a fixed position without imparting any loss to the elasticity of the 2θ actual mattress.

The mattress filling machine 6 in FIG. 3 is used to complete the filling operation of the mattress by compressing and filling said mattress into its ticking 15.

Since other types of mattress filling machines may be 20 used for the filling operation of mattresses, the description herewith given relating to the side-wall type filling machine is only exemplary to illustrate one form of filling procedure embodying the invention.

When the preparatory upholstering work of the inner3Q spring structure is completed, then the mattress is ready for the filling into its ticking. The filling machine employed for this purpose is shown in FIG. 3 of known type having parallel folding side walls 7 together with locking devices being actuated by lever 8, a rotatable press cover 10 comprising counter weight 16 for balancing said cover, driving mechanism (not shown) for the actuation of filling spoon 11, the shape of which is suited to the size of the mattress and a locking device 18 and 17 for keeping press cover 10 in position during the filling operation.

As shown in FIG. 4 the opened side walls 7 of the filling machine 6 form a trough-like space into which the mattress can be easily inserted. By closing side-wall 7 in direction of arrow B, the overlapping edges of lower plastic foam sheet 5 will be bent into position and simul45 taneously the overlapping edges of upper plastic foam sheet 5 are bent manually in direction of arrow A to hold in position said edges by closed side walls 7, as shown in FIG. 3. The rear end of the overlapping edges facing the filling spoon 11 is effected in the same manner as the sides 5θ· by manually bending said edges in contact with the filling spoon 11.

It is a distinctive feature of the present invention for filling mattresses that to make possible the smooth conveying of mattress into its ticking and to reduce the 55 friction between the plastic foam sheet and the enclosing inner surfaces of the filling machine, there is provided a thin layer 12 of material of antifriction nature, such as cotton w'ool, synthetic fiber or a powder of the same nature, as shown in FIG. 4, covering the whole outer sur60 face of plastic foam sheet 5.

It is now possible by this arrangement that the mattress even under compression will be carried neatly into its ticking 15, in direction of arrow D as shown in FIG. 5. The conventional type mattresses employing a thick layer 65 of upholstering over the surface to be contact with the ticking have the disadvantage that after certain time of use the thick layer will lose its elasticity and will show an unporous layer with the further disadvantage, as previously described.

Before closing press cover 19, gate 14 is raised to the height of the mattress to which gate the mattress is advanced and thereby the front overlapping edges of the

3,200,418

INNERSPRING MATTRESS WITH PLASTIC FOAM COVER

Wilhelm Lebens, Leuchtenburg, Germany

Filed Nov. 2,1961, Ser. No. 150,118 5

Claims. (CI. 5-—351)

The present invention relates to means and method of making an improved mattress, in particular to innerspring mattress having a cover layer of resilient material for ₁₀maintaining long lasting form and a desired degree of elasticity of the mattress.

It has been known to manufacture mattresses of plastic foam or other resilient lightweight materials. Such known mattresses had the disadvantage of being not po- 15 rous enough to maintain a desired degree of ventilation after compression and further on account of their limited range of elasticity, an additional spring mattress of higher elasticity range had to be used.

It has also been known to cover both sides of the 20 mattress with a plastic foam layer being approximately the size of the top and bottom parts of the mattress and to maintain the layer in position. Attempts have been made to shape the layer in the form of a cap enclosing the innerspring structure of the mattress, however, the 25 disadvantage remained in the costly and complicated process of manufacture. Another disadvantage could be found in the known type of matttresses using plastic foam covers that in maintaining the foam sheet in position on the spring frame of the mattress, the edges of the foam 30 sheet were bent and glued together whereby a further disadvantage existed in that the vertical movement of the springs and thereby the inwardly bending edges of the foam cover were clamped in the springs and so causing a rapid wear-out of the mattress. 35

The present invention aims to obviate the above mentioned disadvantages whereby a novel combination of an innerspring mattress together with a sheet of resilient foam material is utilized.

It is an object of the present invention to provide for 40 a mattress of the innerspring mattress type having a cover layer of resilient. material which is simple in construction and economical to manufacture.

It is another object to provide for a mattress combining the advantages of the innerspring mattress with those 45 of the foam mattress type.

It is also an object of the invention to provide for a mattress of the character indicated that is light in weight and at the same time maintaining the elasticity of the innerspring mattress and softness of a plastic foam mat- 50' tress without effecting the elasticity of the mattress itself.

These and other object and advantages of the present invention will be more clearly understood when considered in conjunction with the accompanying drawings in which 55

FIG. 1 is a perspective view of a mattress embodying the invention,

FIG. 2 is an enlarged part-sectional view showing the fixing of the intermediate layer, as is shown in FIG. 1,

FIG. 3 is a perspective view of a mattress filling ma- 60 chine,

FIG. 4 is a cross-sectional view of the mattress showing the overlapping edges of the plastic foam sheet prior to bending by side-walls of the filling machine, 'FIG. 5 is a cross-sectional view of the mattress in its compressed form prior to filling into its ticking,

FIG. 6 is an enlarged cross-sectional view of a mattress after having been filled into its ticking, and

FIG. 7 is an enlarged part-sectional view of 'the mattress with modification embodying the invention.

Referring first to FIG. 1 the mattress there illustrated comprises spring frame 3 and springs 1, together form3,200,418 plastic foam sheet are bent in position in similar manner as the side edges shown in FIG. 5. After pulling down press cover 10, which is easily shut by means of a handwheel 21, in FIG. 3, gate 14 is lowered to give free way for the advancing mattress which is moved forward by 5 filling spoon 11. Before commencing the actual filling a ready sewn ticking is pulled over the front end of closed press cover 18 and bottom guide walls 9, as shown in FIG. 5. By withdrawing gate 14 in direction of arrow C the overlapping front edges of plastic foam sheet S will oc- ₁₀cupy their initial horizontal position, however, on advancement of the mattress further in contact with the ticking IS, said overlapping edges will be folded into their bent-in position prior of opening gate 14. Thus, it may be observed that the mattress is carried neatly into its tick- jg ing by the filling spoon 11 without ramming or stuffing. Since the advancing mattress is carried by the filling spoon 11 right into its ticking 15 and by terminating the movement of said filling spoon only when the ticking is fully filled, it will maintain a tight form of the mattress on 20 account of the relieved compression of the innerspring structure leaving the filling machine 6.

When filling is completed, the spoon 11 returns to its initial position and the machine stops automatically. A work-bench 19 is provided for accepting the advancing 25 and completely filled mattress. After the filling operation the rear end of the mattress is sewn together thereby maintaining the bent-in edges in their intended position.

FIG. 6 is a cross-sectional view of an innerspring mattress with plastic foam covering according to the invention 30 showing the respective layers in position as described above. The height chosen for the innerspring structure will be in accordance with the required depth of the bed, which in most cases is 16 cm. The rubberized intermediate layer 2 covering innerspring structure may have 35 a thickness of 3-4 mm. providing a sufficient overall strength for evenly distributing the adjacently acting individual spring forces of the innerspring structure. The metal frame and the continuously wound coil springs may have an anti-rust coating to maintain a clean interior and 40 elasticity of the mattress. Since the individual spring forces have been evenly distributed by intermediate layer 2, the covering plastic foam sheets, 5, 5 may have a reduced thickness in the range of 25-30 mm. The intermediate layer 2 preferably may have a weight of 450-500 45 g./m.². If this weight is increased, the result will be a mattress with higher stiffness and if it is reduced, a mattress with less stiffness will result.

The layer 12 provided for the easy conveying of mattress into its ticking may have a thickness of 1 mm. or 50 less. It may be omitted, if the outer surface of resilient foam material 5 is provided i.e. with an impregnated layer of antifriction nature for the smooth sliding of said mattress.

The width of the overlapping part of the plastic foam sheet 5 is chosen in such a manner that after bending the top and bottom foam layer, there is a gap d provided all around the sides of the mattress, which gap further means a space in which the up and down movement of the plastic foam cover edge can take place without any jamming or clamping by springs 1 of the innerspring structure.

In FIG. 7 there is shown in part-section an innerspirng mattress with plastic foam cover being identical with that of FIG. 6 and in addition showing ticking 15α into which the mattress is compressed and filled in the manner . ⁴ as described and by retaining the original ticking 15 which in this arrangement is made to be easily changeable for replacement or for cleaning. This embodiment as shown in FIG. 7 is particularly advantageous for medical purposes whereby the mattress can be used on both sides which is hygenic in use. After use the outer ticking 15 may be pulled off, and the inner ticking 15α together with the innerspring structure may be put into a disinfectant bath provided the metal parts are made of rust-proof material or have an anti-rust coating. In general the material for the inner cover ticking 15α may be of nettle fiber and the material for the outer ticking 15 may be of any durable textile, preferably being of reinforced cotton nature.