# Patent

## Title
Air mattress

## Abstract

Disclosed herein is an air mattress including at least two separate zones. A first and second groups of elongate, inflatable cells are disposed alternately within each of the at least two separate zones. An air pump is to supply pressurized air. At least two air distributors are serially connected with the air pump for respectively distributing the pressurized air to the at least two separate zones. Each air distributor is operable to supply the pressurized air to the first and second groups of cells within each of the at least two separate zones. A pressure reducer is serially connected between any adjacent two of the at least two distributors for reducing the pressure of the pressurized air to a downstream one of any adjacent two of the at least two distributors.

## Background
BACKGROUND
1. Field of Invention
The present invention relates to an air mattress with air pressure control.
2. Description of Related Art
Air mattresses are used with cots and beds to provide yieldable body support. The air mattresses are inflated with pumps, such as hand operated or bag pumps. Motor driven blowers and pumps have also been to supply air under pressure to air mattresses. The biasing or firmness characteristics of an air mattress is determined by the pressure of the air in the air mattresses. The air mattress firmness can be varied by supplying additional air or venting air from the air mattress. Control mechanisms have been used to adjust the inflation of the air mattress. Even better control mechanisms applied to the air mattresses are necessary when the air mattresses are designed for a patient who is confined on the air mattresses for an extended period of time.
SUMMARY
In one aspect of this invention, an air mattress includes at least two separate zones. A first and second groups of elongate, inflatable cells are disposed alternately within each of the at least two separate zones. An air pump is to supply pressurized air. At least two air distributors are serially connected with the air pump for respectively distributing the pressurized air to the at least two separate zones. Each air distributor is operable to supply the pressurized air to the first and second groups of cells within each of the at least two separate zones. A pressure reducer is serially connected between any adjacent two of the at least two distributors for reducing the pressure of the pressurized air to a downstream one of any adjacent two of the at least two distributors.
Thus, the air pump is serially connected with several air pressure control devices to control multiple zones of an air mattress so as to reduce necessary air pressure control devices.
It is to be understood that both the foregoing general description and the following detailed description are by examples, and are intended to provide further explanation of the invention as claimed.



BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention. In the drawings,
FIG. 1 illustrates a block diagram of an air mattress with air pressure control according to one embodiment of this invention;
FIG. 2 illustrates a diagram of an air pump set for an air mattress according to another embodiment of this invention;
FIG. 3 illustrates an air distributor module of the air mattress according to another embodiment of this invention;
FIG. 3A illustrates a side view of the air distributor module in FIG. 3;
FIG. 4A-FIG. 4D respectively illustrate four operation modes of the air distributor module in FIG. 3;
FIG. 5 illustrates an exploded view of a pressure reducer in FIG. 2; and
FIG. 5A and FIG. 5B respectively illustrate two operation modes of the pressure reducer in FIG. 5.



DESCRIPTION OF THE EMBODIMENTS
Reference will now be made in detail to the present embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the description to refer to the same or like parts.
FIG. 1 illustrates a block diagram of an air mattress with air pressure control according to one embodiment of this invention. The air mattress 100 with air pressure control includes two separate zones (102 and 104) or more, within each zone of which a first and second groups of elongate, inflatable cells, e.g. cells U1 and cells U2 in the zone 102 or cells L1 and cells L2 in the zone 104, are alternately arranged. The zone 102 may be designed for supporting a patent's upper body while the zone 104 may be designed for supporting a patent's lower body. The air mattress firmness of the zone 104 may be lower than that of the zone 102 such that the patent's lower body, e.g. legs or feet can be of comfortable support. An air pump 106 supplies pressurized air to the air mattress 100 and the pressure of the air in the air mattress is varied by various air pressure control devices, i.e. 108, 110, 112 and 114, illustrated in the drawings. In particular, two air distributors (108, 114) are serially connected with the air pump 106 for respectively distributing the pressurized air to the two separate zones (102, 104). Each air distributor (108 or 114) is operable to supply the pressurized air to the first and second groups of cells (U1 and U2 or L1 and L2) within each of the at least two separate zones. If the air mattress is divided into three or more zones, three or more distributors are needed to control respective zones. A pressure reducer 112 is serially connected between two distributors (108, 114) for reducing the pressure of the pressurized air to the downstream distributor 114. If there are three or more distributors, a pressure reducer is serially connected between any adjacent two of the three or more distributors for reducing the pressure of the pressurized air to a downstream one of any adjacent two distributors. A regulator 110 may be serially connected between the pressure reducer 112 and the upstream air distributor 108. If there are three or more distributors, a regulator is serially connected between the pressure reducer and an upstream one of any adjacent two of the three or more distributors.
FIG. 2 illustrates a diagram of an air pump set for an air mattress according to another embodiment of this invention. An air pump 206 is to supply pressurized air. Two air distributors (208, 214) are serially connected with the air pump 206. A pressure reducer 212 is serially connected between two air distributors (208, 214) for reducing the pressure of the pressurized air to the downstream distributor 214. A regulator 210 may be serially connected between the pressure reducer 212 and the upstream air distributor 208.
The air distributor 208 has an inlet and four outlets. The inlet 208a of the air distributor 208 is connected to the air pump 206 to receive the pressurized air. Two outlets (208b, 208c) are to distribute the pressurized air to respective air-requiring targets, e.g. inflatable cells U1 and U2 in FIG. 1. An outlet 208e is connected to the regulator 210 or directly to the pressure reducer 212 (if the regulator 210 is not installed). An outlet 208d is to vent air out. The air distributor's operation mechanisms are illustrated and articulated in the embodiments of FIG. 4A through FIG. 4D.
The pressure reducer 212 has two pairs of inlets and outlets, i.e. inlet 212c, outlet 212b, inlet 212e and outlet 212d. A user may turn a knob 212a to switch the pressure reducer 212 between two pressure reducing ratios. The inlet 212c of the pressure reducer 212 is connected to the outlet 208e of the air distributor 208 (if the regulator 210 is not installed) or the regulator 210 whereas the outlet 212b of the pressure reducer 212 is connected to the downstream air distributor 214. The inlet 212e of the pressure reducer 212 is also connected to the downstream air distributor 214. The outlet 212d is to vent air out. The pressure reducer's detailed structures are illustrated and articulated in the embodiment of FIG. 5, and its operation mechanisms are illustrated and articulated in the embodiments of FIG. 5A and FIG. 5B.
The air distributor 214 has an inlet and four outlets. The inlet 214a of the air distributor 214 is connected to both the inlet 212e and outlet 212b of the pressure reducer 212. Two outlets (214b, 214c) are to distribute the pressurized air to respective air-requiring targets, e.g. inflatable cells L1 and L2 in FIG. 1. An outlet 214e is connected to a further air distributor or pressure reducer (if necessary), otherwise the outlet 214e may be sealed. An outlet 214d is to vent air out. The air distributor's operation mechanisms are illustrated and articulated in the embodiments of FIG. 4A through FIG. 4D.
The regulator 210 may be serially connected between the pressure reducer 212 and the upstream air distributor 208 to regulate down the pressure of all the pressurized air (supplied by the air pump 206) upstream the pressure reducer 212.
FIG. 3 illustrates an air distributor module of the air mattress according to another embodiment of this invention, and FIG. 3A illustrates a side view of the air distributor module in FIG. 3. The air distributor module 300 basically consists of two air distributors combined. Each air distributor consists of two disc-shaped halves, e.g. disc-shaped halves (302a, 304a) or disc-shaped halves (302b, 304b), rotatably interconnected with each other to form chambers therebetween for distributing air out through various outlets thereof. A rotatable shaft 301a is inserted through all the disc-shaped halves and driven by a motor 301. Rotatable disc-shaped halves (302a, 302b) are secured to the shaft 301a, e.g. using a pin 303 penetrating the shaft 301a such that the disc-shaped halves (302a, 302b) can be rotated simultaneously with the shaft 301a. Static disc-shaped halves (304a, 304b) are equipped with all inlets and outlets, and do not rotate relative to the motor 301, i.e. the static disc-shaped halves (304a, 304b) are not secured to the shaft 301a. A compression spring 306 is arranged between the disc-shaped half 302b and the motor 301 (and around the shaft 301a) to press the four disc-shaped halves together. Each interface between any adjacent two disc-shaped halves may be lubricated by a friction-reducing substance, for example, silicone so as to smoothen the rotating of disc-shaped halves (302a, 302b) as well as to keep each interface airtight sealed.
The advantages of combining two air distributors includes at least the following:

    
    
        (1) Only one motor 301 and one controller 310 (or timer) are necessary to control two air distributors, instead of one motor and one controller being conventionally used to control one air distributor; and
        (2) Disc-shaped halves (302a, 302b) can be easily controlled to rotate simultaneously because both of them are secured to the same shaft 301a. 
    
    


FIG. 4A-FIG. 4D respectively illustrate four operation modes of the air distributor module in FIG. 3. It should be noted that each Figure illustrates single one air distributor, i.e. two disc-shaped halves (302a, 304a). The rotatable disc-shaped half 302a is labeled with T1 and T2 to clearly indicate its orientation in four Figures. The chamber layout between two disc-shaped halves is roughly illustrated in dashed-lines.
In FIG. 4A, the disc-shaped half 302a is at the position with T1 at a right-hand side and T2 at a left-hand side. In this operation mode, an inlet 320a and three outlets (320b, 320c, 320e) are gas-interconnected, i.e. gas can be transferred through, to one another. That is, the pressurized air can be input through an inlet 320a and output through outlets (320b, 320c, 320e). The outlet 320e is connected to a regulator, a pressure reducer or another downstream air distributor. In this operation mode, an outlet 320d, which is to vent air out, is not gas-interconnected to the inlet 320a or three outlets (320b, 320c, 320e).
In FIG. 4B, the disc-shaped half 302a is at the position with T1 at a lower side and T2 at an upper side. In this operation mode, an inlet 320a and two outlets (320c, 320e) are gas-interconnected to one another whereas the two outlets (320h, 320d) are gas-interconnected to each other. That is, the pressurized air can be input through an inlet 320a and output through outlets (320c, 320e). The outlet 320e is connected to a regulator, a pressure reducer or another downstream air distributor.
In FIG. 4C, the disc-shaped half 302a is at the position with T2 at a right-hand side and T1 at a left-hand side. In this operation mode, an inlet 320a and three outlets (320b, 320c, 320e) are gas-interconnected to one another. That is, the pressurized air can be input through an inlet 320a and output through outlets (320b, 320c, 320e). The outlet 320e is connected to a regulator, a pressure reducer or another downstream air distributor. In this operation mode, an outlet 320d, which is to vent air out, is not gas-interconnected to the inlet 320a or three outlets (320b, 320c, 320e). The operation mechanism in FIG. 4C is the same as that in FIG. 4A.
In FIG. 4D, the disc-shaped half 302a is at the position with T2 at a lower side and T1 at an upper side. In this operation mode, an inlet 320a and two outlets (320b, 320e) are gas-interconnected to one another whereas the two outlets (320c, 320d) are gas-interconnected to each other. That is, the pressurized air can be input through an inlet 320a and output through outlets (320b, 320e). The outlet 320e is connected to a regulator, a pressure reducer or another downstream air distributor.
FIG. 5 illustrates an exploded view of a pressure reducer in FIG. 2. The pressure reducer 212 basically consists of a hollow cylinder 211, a cylinder core 213 and a knob 212a. A connection member 215 (a hollow cylinder) is used to rotatably connect the cylinder core 213 within the hollow cylinder 211. The connection member 215 is firmly fitted within an inner surface 212f of the hollow cylinder 211. The cylinder core 213 has its threaded portion 213a loosely meshed with a thread inner surface 215a of the connection member 215 such that the cylinder core 213 is rotatable relative to the connection member 215 and the hollow cylinder 211. Besides the threaded portion 213a, a lower unthreaded portion of the cylinder core 213 is also loosely fitted within the inner surface 212f of the hollow cylinder 211, i.e. there is a gap between the inner surface 212f and the lower unthreaded portion of the cylinder core 213.
The cylinder core 213 has two air channels (213b, 213c) whereas the hollow cylinder 211 has two pair two pairs of inlets and outlets, i.e. inlet 212c, outlet 212b, inlet 212e and outlet 212d. Each channel penetrates through the cylinder core 213 and has two openings on an outer surface of the cylinder core 213. Each air channel (213b, 213c) is employed to interconnect between each pair of inlet and outlet such that the air can be transferred through thereof.
The knob 212a is secured to a top end 213g of the cylinder core 213 to be rotated by a user so as to enable the air channel 213b or air channel 213c to be interconnected between a corresponding pair of inlet and outlet.
Three O-rings (217a, 217b, 217c) are respectively fitted into three grooves (213d, 213e, 2130 of the cylinder core 213. The O-ring 217b is located between the air channel 213b and air channel 213c. The air channel 213b is located between the O-ring 217a and the O-ring 217b while the air channel 213c is located between the O-ring 217b and the O-ring 217c (when three O-rings are respectively fitted into three grooves). Each O-ring is to airtight seal the gap between the inner surface 212f and the lower unthreaded portion of the cylinder core 213.
FIG. 5A and FIG. 5B respectively illustrate two operation modes of the pressure reducer in FIG. 5. These two Figures only illustrate the lower portion of the pressure reducer.
FIG. 5A illustrates a first position of the cylinder core 213 relative to the hollow cylinder 211 where the air channel 213b interconnects between the pair of inlet 212c in and outlet 212b, and the air channel 213c does not interconnect between the pair of inlet 212e and outlet 212d. Although the air channel 213c does not interconnect between the pair of inlet 212e and outlet 212d, the pair of inlet 212e and outlet 212d are stilled gas-connected, i.e. gas can be transferred through the gap between the cylinder core 213 and the hollow cylinder 211. That is, the airflow rate through the pair of inlet 212c and outlet 212b is greater than the airflow rate through the pair of inlet 212e and outlet 212d when the cylinder core 213 is at the first position relative to the hollow cylinder 211.
FIG. 5B illustrates a second position of the cylinder core 213 relative to the hollow cylinder 211 where the air channel 213c interconnects between the pair of inlet 212e and outlet 212d, and the air channel 213b does not interconnect between the pair of inlet 212c and outlet 212b. Although the air channel 213b does not interconnect between the pair of inlet 212c and outlet 212b, the pair of inlet 212c and outlet 212b are stilled gas-connected through the gap between the cylinder core 213 and the hollow cylinder 211. That is, the airflow rate through the pair of inlet 212e and outlet 212d is greater than the airflow rate through the pair of inlet 212c and outlet 212b when the cylinder core 213 is at the second position relative to the hollow cylinder 211.
Referring to FIG. 2, FIG. 5A and FIG. 5B, when the pressure reducer 212 is used in the pump set in FIG. 2, the inlet 212c is connected to an upstream air distributor or regulator, the inlet 212e and outlet 212b are both connected to the inlet 214a of the downstream air distributor 214, and the outlet 212d is to vent air out.
When a user rotates the knob 212a to switch the cylinder core 213 at the first position relative to the hollow cylinder 211 (where the air channel 213b interconnects between the pair of inlet 212c and outlet 212b), the pressurized air through the pair of inlet 212c and outlet 212b will be transferred to the downstream air distributor 214 in larger part and transferred through the pair of inlet 212e and outlet 212d in smaller part. Therefore, the pressure of the pressurized air is dropped down by the pressure reducer 212.
When a user rotates the knob 212a to switch the cylinder core 213 at the second position relative to the hollow cylinder 211 (where the air channel 213c interconnects between the pair of inlet 212e and outlet 212d), the airflow rate through the pair of inlet 212c and outlet 212b is smaller than the airflow rate through the pair of inlet 212e and outlet 212d. In this case, the downstream airflow is flowed back through the pair of inlet 212e and outlet 212d while the pressurized air is still transferred through the pair of inlet 212c and outlet 212b. Therefore, in this case (the cylinder core 213 at the second position relative to the hollow cylinder 211), the pressure of the pressurized air is dropped even down by the pressure reducer 212 compared with the case where the cylinder core 213 is at the first position relative to the hollow cylinder 211.
According to the discussed embodiments herein, the air pump is serially connected with several air pressure control devices to control multiple zones of an air mattress so as to reduce needed air pressure control devices. Besides, two air distributors are combined and driven by a single motor such that less motors and controllers are needed to operate the air mattress.
It will be apparent to those skilled in the art that various modifications and variations can be made to the structure of the present invention without departing from the scope or spirit of the invention. In view of the foregoing, it is intended that the present invention cover modifications and variations of this invention provided they fall within the scope of the following claims and their equivalents.

## Claims

1. An air mattress comprising:
at least two separate zones;
a first and second groups of elongate, inflatable cells disposed alternately within each of the at least two separate zones;
an air pump for supplying pressurized air;
at least two air distributors serially connected with the air pump for respectively distributing the pressurized air to the at least two separate zones, each air distributor being operable to supply the pressurized air to the first and second groups of cells within each of the at least two separate zones; and
a pressure reducer serially connected between any adjacent two of the at least two distributors for reducing the pressure of the pressurized air to a downstream one of any adjacent two of the at least two distributors.

2. The air mattress of claim 1, wherein the first and second groups of cells are disposed adjacent to each other and generally in parallel with each other.

3. The air mattress of claim 1, further comprising a regulator serially connected between the pressure reducer and an upstream one of any adjacent two of the at least two distributors.

4. The air mattress of claim 3, wherein an upstream one of the at least two distributors comprises an air inlet and three air outlets, the air inlet is connected to the air pump, two of the three air outlets are respectively connected to the first and second groups of cells, the remaining air outlet is connected to the regulator.

5. The air mattress of claim 1, wherein an upstream one of the at least two distributors comprises an air inlet and three air outlets, the air inlet is connected to the air pump, two of the three air outlets are respectively connected to the first and second groups of cells, the remaining air outlet is connected to the pressure reducer.

6. The air mattress of claim 1, wherein each of the at least two distributors comprises two disc-shaped halves rotatably interconnected with each other.

7. The air mattress of claim 1, wherein any adjacent two of the at least two distributors are interconnected with each other.

8. The air mattress of claim 7, further comprising a motor having a rotatable shaft to connect any adjacent two of the at least two distributors.

9. The air mattress of claim 8, wherein each of the at least two distributors comprises a static disc-shaped half and a rotatable disc-shaped half rotatably interconnected with each other, the rotatable disc-shaped half is secured to the rotatable shaft.

10. The air mattress of claim 9, further comprising a compression spring disposed around the rotatable shaft and between the motor and the rotatable disc-shaped half.

11. The air mattress of claim 1, wherein the pressure reducer comprises:
a hollow cylinder comprising a first pair of inlet and outlet and a second pair of inlet and outlet; and
a cylinder core being loosely fitted within the hollow cylinder, and comprising a first air channel and a second air channel, wherein the cylinder core is rotatable between a first position and a second position relative to the hollow cylinder,
when the cylinder core is at the first position relative to the hollow cylinder, the first air channel interconnects between the first pair of inlet and outlet, and the second air channel does not interconnect between the second pair of inlet and outlet,
when the cylinder core is at the second position relative to the hollow cylinder, the second air channel interconnects between the second pair of inlet and outlet, and the first air channel does not interconnect between the first pair of inlet and outlet.

12. The air mattress of claim 11, further comprising a knob secured to the cylinder core and sticking out of the hollow cylinder.

13. The air mattress of claim 11, wherein the pressure reducer further comprises:
a first O-ring disposed between the hollow cylinder and the cylinder core, and between the first and second air channels.

14. The air mattress of claim 13, wherein the pressure reducer further comprises:
a second O-ring and a third O-ring both disposed between the hollow cylinder and the cylinder core,
wherein the first air channel is disposed between the first O-ring and the second O-ring,
wherein the second air channel is disposed between the first O-ring and the third O-ring.

15. The air mattress of claim 14, wherein the cylinder core comprises three grooves to be respectively fitted by the first, second and third O-rings.

16. The air mattress of claim 11, further comprising a connection member firmly fitted within part of the hollow cylinder and has a threaded inner surface.

17. The air mattress of claim 16, wherein the cylinder core comprises a threaded portion to be loosely meshed with the threaded inner surface of the connection member.