Under Mattress For Reclining Furniture

Abstract

The invention relates to an under mattress for reclining furniture, the under mattress having two relatively pivotable sections which can be interlocked in a number of different adjustable positions. The locking device is stated to comprise pairs of interdigitated assemblies having recesses formed in edges thereof, and a manually operated pivoted pawl having a locking tooth engageable in aligned recesses of said pair. A mechanism for releasing the locking device from a freed position when the under mattress reaches a horizontal disposition is disclosed.

Description

BACKGROUND OF THE INVENTION

The present invention relates to an improvement in or modification of the under mattress for reclining furniture described and claimed in the specification of British Pat. No. 1,257,657.

The subject matter of the British Patent relates to an under mattress frame for reclining furniture which comprises a frame which is tiltably mounted in side portions of the reclining furniture, and which is subdivided into at least two sections which are relatively pivotable about an axis transverse to the longitudinal axis of the reclining furniture, the two sections being lockable by stop means, operable by a person resting on the under mattress, in a substantially horizontal stop position and one other stop position.

The under mattress according to the broadest claim of the British Patent is further limited in that the stop means has on each side of one frame section a pivotably mounted locking member, each locking member overlapping the adjacent frame section to positively engage with locking means provided on the latter in each stop position of the under mattress but to adjustably engage in positions of the under mattress intermediate the stop positions, whereby the two frame sections can assume any relative angular relationship between the two stop positions in response to movements of a person resting on the under mattress, the stop means automatically becoming locked when the two frame sections reach said substantially horizontal stop position.

Heretofore embodiments of under mattress in accordance with the invention have employed locking members which are largely located on the outsides of the reclining furniture (in order to prevent parts thereof from being obstructed by the mattress). Apart from aesthetic objections, this location readily causes damage

SUMMARY OF THE INVENTION

According to the present invention an under mattress for reclining furniture having a frame which is pivotally mounted in side portions of the reclining furniture and is subdivided into at least two sections which are relatively pivotable about an axis transverse to the longitudinal axis of the reclining furniture, the angular position of the two sections being lockable by a stop means operable by a person resting on the under mattress in a substantially horizontal stop position and at least one other stop position, is characterised in that the stop means comprises locking devices provided on each side of the frame at the ends of each section adjacent to the pivoting axis each locking device comprising a plurality of parallel spaced-apart arresting plates forming an assembly rigidly attached to its associated section of the frame, edges of the plates in each assembly being formed with a plurality of relatively aligned recesses, with leading portions of the corresponding assemblies of the two locking devices attached to the adjoining sections of the frame interdigitating on each side of the frame, whereby the assemblies forming each pair of interdigitated assemblies are relatively turnable when the two sections of the frame are relatively tilted, there being provided adjacent to the recessed edges of at least one pair of interdigitated assemblies a locking pawl which is manually tiltable about a pivot and having a locking tooth which points towards the recesses in the arresting plates, the pawl being resiliently urged into locking engagement with said recesses.

This new form of construction of stop means is not only more robust and functionally more reliable than the arrangement disclosed in the prior patent, it also makes for greater comfort. As will yet be described in greater detail with reference to the drawings, the user of an under mattress in accordance with a preferred embodiment of this invention can now choose between several different, for instance three different, angles of relative tilt of the two sections of the frame and still achieve the free floating angled reading position by performing a single manipulation, from which the fully extended sleeping position can be automatically obtained without effort simply by stretching out the body into sleeping position.

In a particular embodiment a strap loop may be attached to that end of the locking pawl which is remote from the locking tooth and adapted to be retained (e.g., frictionally) by a retaining element on one longitudinal side of the frame thereby to keep the locking pawl out of engagement.

The recesses in all the arresting plates may preferably be arranged on an arc of a circle about the axis of the hinge between the two sections of the frame.

Preferably two locking pawls are provided and the or each locking pawl may be formed on its underside with a ramp at a distance from the axis of the hinge joining the two sections of the frame, which distance, when the or each pawl is disengaged, exceeds the distance from the axis of the adjacent upper edge of a bottom web of the frame in such manner that the upper edge will ride under the ramp of the or each disengaged locking pawl when the two sections of the frame are deflected into their fully extended position, and force the or each pawl upwards into locking position by overcoming frictional resistance employed to hold the pawl in its disengaged position.

BRIEF DESCRIPTION OF THE DRAWINGS

One embodiment of under mattress in accordance with the invention is illustratively shown in the accompanying drawings, in which:

FIG. 1 is a perspective view of an under mattress frame,

FIG. 2 is a side view of a constructional detail on a larger scale,

FIG. 3 is a view of the detail in FIG. 2 from below,

FIGS. 4 and 5 illustrate the manner in which the mattress frame functions by showing two different positions, and

FIG. 6 is another constructional detail.

DETAILED DESCRIPTION OF THE INVENTION

In the illustrated embodiment in FIG. 1 the mattress frame is a box frame generally indicated by 1 with a bottom formed by transverse wooden slats, of the kind known as laminated wood springs 2, suspended in any desired manner - but preferably as described in UK Patent Specification No. 1,257,657, between the longitudinal side members 3 and 4 of the box frame 1. The frame 1 is divided into two parts 1a and 1b (FIG. 3), which are hingeably connected together for relative tilting movement about an axis A--A.

Mounted on the outside of each longitudinal member 3 and 4 of part 1b of the frame is a supporting element 5 in the form of a roller which fits into a correspondingly shaped holder on the chassis, not shown, of the reclining chair. The other part 1a of the frame may be fitted on each side with a pin 6 (FIG. 1) for slidably engaging a horizontal slot in the inner surface of a chassis member facing the longitudinal members 3 and 4. However, the frame 1 could be mounted on the chassis in some other way (for instance by a pair of pins 6 and an arrangement for supporting the feet in a raised position) provided that one of the support means allows for the longitudinal displacement which occurs when the two parts 3 and 4 are relatively hingeably tilted or folded.

A locking device constructed in a manner illustrated in FIGS. 2 and 3 is associated with the hinge between the two parts of the longitudinal members 3 and 4 of the frame.

As already mentioned, the two parts of the longitudinal side members 3 and 4 are connected by two hinges 8 (FIG. 2) for relative tilting movement about the axis A--A. In the region of these hinges, several arresting plates 9a and 9b are attached alternately by pins 12 to the insides of two U-shaped metal sections 10a and 10b so that each arresting plate 9a attached to the section 10a projects into the space separating two arresting plates 9b. in the cooperating section. The hinge pins 8 pass through all the arresting plates 9a and 9b and their plates can thus be relatively rotated together with the parts 1a and 1b of the frame to which they belong.

The precise shape of the arresting plates is more particularly illustrated in FIG. 6. The end portion of each arresting plate facing a cooperating arresting plate is formed with a plurality of recesses 13 which are of exactly the same size and equally spaced in all the arresting plates. Hence all the recesses 13 in one group of plates 9a transversely align and the recesses 13 of both groups of plates 9a and 9b will register when the two groups of plates are in a number of predetermined relative angular positions.

However, all the arresting plates 9a on the one hand and all the arresting plates 9b on the other hand form rigid assemblies attached to the sections 10a and 10b by the pins 12. Holes 14 (FIG. 6) in the plates serve for the reception of the hinge pin 8 (FIG. 3) to permit the two groups of arresting plates 9a and 9b to be relatively rotated. The recesses 13 are located on circular arcs about the axis of the hinge (i.e., the axis of all the holes 14).

Furthermore, as can be seen by reference to FIG. 2, on each side of the frame 1 a locking pawl 15 (of. FIGS. 4/5) is fast on a shaft 16 pivotally mounted adjacent to the bottom edge of the U-shaped section 10a, the end of the pawl 15 being formed with an upwardly pointing locking tooth 17. The pawl 15 and its shaft 16 are so located that the locking tooth 17 is situated below the recesses 13 (FIG. 6) when the two parts 1a and 1b of the frame are relatively tilted. A spring is arranged to urge the locking tooth of the pawl into engagement with one of these recesses.

The shaft 16 extends across the width of the frame 1 and is common to both of the pawls. The shaft can be easily inserted into appropraite holes and also replaced and can be secured in working position by a pin 18 (FIG. 3) which engages a longitudinal slot and a hole extending at right angles thereto. The pin 18 is itself prevented from falling out by an elastic push-on sleeve 19.

Each pawl 15 is rigidly connected to an actuating arm 20 which is loaded by a spring 21 schematically indicated in FIG. 2 of the drawing. The lever carries a metal friction plate 22 which can be pulled by means of a strap loop 23 into the peripheral groove 24a of a friction roller 24 and jammed in position. Since the peripheral groove 24a has a cross section which inwardly narrows, the friction plate 22 can be wedged in the roller groove simply by pulling the strap loop upwards as indicated by an arrow 25. In the resultant position of the arm 20 the locking tooth 17 is not in engagement (cf. FIG. 5) and the two parts of the frame can freely swing about their interconnecting hinge.

However, if the locking pawl 15 is in the position shown in FIG. 2 the two parts 1a and 1b of the frame will be locked together in their fully extended flat position (FIG. 1). If the reclining person wishes to sit up, for instance in order to read, he or she need merely pull up the strap 23, causing the locking tooth 17 to be withdrawn from the corresponding recess 13. The two parts of the frame are then no longer interlocked and the desired relatively angled position can be selected simply by suitably shifting the weight of the body. When the strap loop 23 is released the locking tooth 17 is urged by the spring 21 to engage the recess with which it happens to register and the frame will be locked in the corresponding angular position.

In the described and illustrated embodiment the frame can be locked in three different angular positions. The snap engagement of the locking tooth 17 occurs whenever the recesses 13 of the two groups of arresting plates 9a and 9b are in alignment. The correct locking position can be easily found by slightly rocking the two parts of the frame.

When the friction plate 22 has been pulled into the peripheral groove of the retaining roller 24 so that it jams, then the two parts of the frame will be in an angularly freely floating position and can be relatively inclined or flattened out as may be desired until the resting person goes to sleep and the fully extended position is reached.

However, the arrangement so far described still has one drawback. This is that the continued engagement of the two friction members 22 and 24 in the fully extended flat position for sleeping might result in subconscious movements of the sleeping person causing the two parts of the frame to swing about their hinge and to assume an uncomfortable angle. In a preferred embodiment of the described arrangement this cannot occur because each locking pawl 15 is formed on its underside with a ramp 26 which in the locking position shown in FIG. 5 is slightly further away from the hinge 8 than corresponds to the distance marked 1 in FIG. 4 between the hinge 8 and the surface 27 of the bottom web of the U-section. Therefore, when the two parts of the frame approach their fully extended position the leading edge 28 of the section 10b will engage the ramp 26 from underneath and force it upwards, thereby pulling the friction plate 22 out of the peripheral slot 24 in the retaining roller by overcoming the frictional resistance to the separation of these two parts. By an appropriate choice of materials, for instance by pairing a metal plate 22 and a nylon roller 24, the desired effect can be readily achieved. This ensures that the parts of the frame will automatically lock when they are fully extended.

As illustrated in FIG. 6 the first tooth 29 on each arresting plate 9a/9b is a little larger than the other teeth between the recesses 13. This ensures that when the frame is in the free floating position and the friction plate has been jammed as in FIG. 5, the locking tooth 17 of the locking pawl 15 will strike the tooth 29 when a minimum angle .alpha. between the two parts of the frame has been reached and thus prevent a further inadmissible and undesirable folding of the frame.

The described arrangement combines the advantages of being effortlessly operated, of automatically locking itself in the fully extended position, and of employing a mechanism which is uncomplicated and well secreted.

Claims

What is claimed is:

1. In an under mattress for reclining furniture having a frame which is pivotally mounted in side portions of the reclining furniture and is subdivided into at least two sections which are relatively pivotable about an axis transverse to the longitudinal axis of the reclining furniture, the angular position of the two sections being lockable by a stop means operable by a person resting on the under mattress in a substantially horizontal stop position and at least one other stop position, the improvement wherein: said stop means comprises locking devices provided on each side of said frame at the ends of each section thereof adjacent to said pivoting axis, each device comprising a plurality of parallel spaced-apart arresting plates forming an assembly rigidly attached to its associated section of said frame, edges of said plates in each assembly being formed with a plurality of relatively aligned recesses, with leading portions of the corresponding assemblies of the two locking devices attached to the adjoining sections of said frame interdigitating on each side of said frame, whereby the assemblies forming each pair of interdigitated assemblies are relatively turnable when the two sections of said frame are relatively tilted, there being provided adjacent to the recessed edges of at least one pair of interdigitated assemblies a locking pawl which is manually tiltable about a pivot and having a locking tooth which points towards the recesses in said arresting plates, said pawl being resiliently urged into locking engagement with said recesses, the end of said pawl remote from its locking tooth being attached to a member which is adapted to be frictionally retained by a retaining element on a longitudinal side member of said frame to thereby maintain said locking pawl out of engagement with said recesses, said retaining element comprising a friction roller provided with a peripheral slot which narrows in the radially inward direction.

2. An under mattress frame according to claim 1, in which the friction roller is made of a synthetic plastics material.

3. An under mattress according to claim 1 in which the recesses of all the arresting plates are located on circular arcs about the axis of the hinge joining the two sections of the frame together.

4. An under mattress according to claim 1 in which two locking pawls are provided which are fast on a common shaft extending across the frame.

5. In an under mattress for reclining furniture having a frame which is pivotally mounted in side portions of the reclining furniture and is subdivided into at least two sections which are relatively pivotable about an axis trnsverse to the longitudinal axis of the reclining furniture, the angular position of the two sections being lockable by a stop means operable by a person resting on the under mattress in a substantially horizontal stop position and at least one other stop position, the improvement wherein: said stop means comprises locking devices provided on each side of said frame at the ends of each section thereof adjacent to said pivoting axis, each locking device comprising a plurality of parallel spaced-apart arresting plates forming an assembly rigidly attached to its associated section of said frame, edges of said plates in each assembly being formed with a plurality of relatively aligned recesses, with leading portions of the corresponding assemblies of the two locking devices attached to the adjoining sections of said frame interdigitating on each side of said frame, whereby the assemblies forming each pair of interdigitated assemblies are relatively turnable when the two sections of said frame are relatively tilted, there being provided adjacent to the recessed edges of at least one pair of interdigitated assemblies a locking pawl which is manually tiltable about a pivot and having a locking tooth which points towards the recesses in said arresting plates, said pawl being resiliently urged into locking engagement with said recesses, the end of said pawl remote from its locking tooth being attached to a member which is adapted to be frictionally retained by a retaining element on a longitudinal side member of said frame to thereby maintain said locking pawl of engagement with said recesses, said locking pawl being formed on the underside thereof with a ramp at a distance from said axis of the hinge joining said two sections of said frame, which distance, when said pawl is disengaged, exceeding the distance from said axis to an adjacent upper edge of a bottom web of said frame, whereby said upper edge will ride under said ramp when said two sections of said frame are deflected into their fully extended position, and force said pawl upwards into locking position by overcoming the frictional resistance to release of said clamping member by said retaining element.

6. An under mattress according to claim 5, in which the recesses of all the arresting plates are located on circular arcs about the axis of the hinge joining the two sections of the frame together.

7. An under mattress according to claim 5, in which two locking pawls are provided which are fast on a common shaft extending across the frame.