Ventilation and Cooling System for an Office Chair

Abstract

A ventilation and cooling system for an AERON office chair is disclosed. It consists of an air mover, a power supply unit and a control switch. The system attaches underneath the seat of the chair. Airflow from the air mover is directed towards the seat to dissipate the body heat of the chair's occupant. The increased airflow cools the posterior and crotch regions of the person occupying the chair.

Description

BACKGROUND OF THE INVENTION

The present invention is in the field of personal ventilation and cooling. Specifically, it is a ventilation and cooling system for an office chair.

Ventilation and climate control in office buildings is usually accomplished through centralized units that regulate the temperature of large volumes of air. This sort of regulation inevitably results in variations of the temperature over the space being regulated. On average, the variations are minor and can be ignored. However, there are instances in which sufficiently large temperature variations arise that require local adjustments of the ambient temperature. For example, the person under a vent feels the need to plug in a heater during the summer months when the air conditioning is in full blast. Or conversely, the heat generated by computers under the desks of modern office workers raises the air temperature near the floor making it uncomfortable for people to remain in their seats without some form of local ventilation.

The problem of achieving a comfortable body temperature for an office worker who spends the majority of the day seated is further compounded by insufficient body heat dissipation due to the trapping of body heat by the seating assembly. Conventional office chairs have seating and backrest surfaces that are made of multi-density foam padding with a covering such as cloth, leather or the like. These surfaces do not provide sufficient aeration to the body. The prior art contains examples of chairs with ventilation and cooling systems that attempt to address the problem. There are also a number of inventions that essentially amount to a chair cushion with cooling and/or heating functionality. Similar approaches are also evident in the prior art pertaining to the auto industry, where the trapping of body heat by the seating assembly can make the operator of the vehicle uncomfortable over prolonged periods of time. While it may be practical for an auto manufacturer to design a custom seat with ventilation and cooling features, which is then mass produced as a standard part of the vehicle, it is not practical to expect an employer to offer each employee the option to choose a bespoke chair that is outfitted with a ventilation system. Offices are usually equipped with standard chairs for the vast majority of employees. Relying on a specialized chair cushion for ventilation and cooling of an office chair is thus the only viable option for the vast majority of office workers. However, this approach has the drawback of potentially compromising the comfort and aesthetics of the chair.

The invention disclosed herein offers an alternative to bespoke office chair functionality or chair cushions. It is a ventilation and cooling system for a specific type of office chair that is in wide use today. The chair is manufactured by Herman Miller Inc. and sold under the trademark AERON. Invented in 1992 and disclosed in U.S. Pat. No. 6,386,634 and U.S. Pat. No. 6,059,368, the AERON office chair is arguably the most famous office chair of all time, with a spot in the permanent collection of the Museum of Modern Art. According to some estimates, as many as seven million AERON chairs have been sold. The seating and back support surfaces of this chair are made from a woven fabric membrane that is air permeable, as described in U.S. Pat. No. 6,035,901. Thus, an AERON office chair mitigates body heat build up by allowing the body to aerate through the surfaces of the chair. However, it cannot cool the occupant of the chair below the ambient air temperature. The invention described herein enhances the ventilation attributes of an AERON office chair by increasing the airflow through the seating surface of the chair to cool the posterior and crotch regions of the occupant. The system attaches easily to an AERON office chair without compromising any of its functionality, ergonomic benefits, comfort, aesthetics or mobility.

SUMMARY OF THE INVENTION

The present invention is a ventilation and cooling system for an AERON office chair comprising an air mover, a power supply unit and a control switch. The air mover attaches to two restraining links underneath the seat of an AERON office chair. Electrical power is supplied to the air mover by a power supply unit, which resides in a holster clipped to a horizontal support bar on the side of the chair. A control switch on the power cable connecting the power supply unit and the air mover is used to set the rate of airflow generated by the air mover. The system cools the crotch and posterior of someone seated in an AERON office chair by increasing the dissipation of body heat. When not in use on the chair, the system can provide standalone ventilation and cooling.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows the system mounted on an AERON office chair.

FIG. 2 is a closeup of the air mover, power supply unit, control switch, power cable and holster.

FIG. 3 is an exploded view of the air mover.

FIG. 4 a shows the rotation of the air mover's mounting brackets to point the airflow in a given direction.

FIG. 4 b is a view of the air mover as mounted on the restraining links of the chair with arrows to indicate rotation of the air mover to point the airflow in a preferred direction.

FIG. 5 a is a view of the power supply unit inside the holster.

FIG. 5 b is a view of the power supply unit outside the holster.

FIG. 5 c is a view of the power supply unit's output side.

FIG. 5 d is a view of the power supply unit's input side.

FIG. 6 is a block diagram of the electrical circuits in the system.

DETAILED DESCRIPTION OF THE INVENTION

An AERON office chair 12 having a seat frame 22 and an air permeable, elastic membrane as a seat surface 30 is shown in FIG. 1. In a preferred embodiment of the present invention, an air mover 14 attaches to restraining links 28 underneath the seat frame 22 of the chair. The air mover 14 is connected to a power supply unit 16 residing in a holster 18 clipped to a horizontal bar 26, located on either the left or right hand side of the chair. Placing the power source unit on the chair eliminates the need for a power cable extending from the air mover 14 to a remote power jack, which would restrict the lateral or rotational movements of the chair. A control switch 20 adjusts the rate of airflow generated by the air mover 14. The airflow from the air mover 14 ventilates the space beneath the seat frame 22 and cools the occupant of the chair by dissipating body heat through the air permeable membrane of the seat surface 30.

A significant advantage of the present invention is the ease of installation. It can be accomplished without the use of any tools, thus making the system suitable for installation in an office setting. A close-up of a detached system is displayed in FIG. 2. The air mover 14 attaches to an AERON office chair by means of two clevis mounting brackets 34. The curved ends of these brackets are designed to clip securely onto the restraining links 28, previously shown in FIG. 1. Electrical power is delivered via a power cable 21 terminated in a Type A Universal Serial Bus (USB) plug 32, which is plugged into the power supply unit 16. The control switch 20 that sets the rate of airflow generated by the air mover 14 is connected through the power cable 21. The holster 18 is designed with dimensions that allow it to attach to the chair by means of clipping to the horizontal bar 26, also previously shown in FIG. 1. When attached to the chair, the holster is easily accessible, enabling the occupant seated in the chair to replace the power supply unit 16 without needing to get up from the chair. In an alternative application, the system can be used for standalone ventilation and cooling.

An exploded view of the air mover is shown in FIG. 3. In the preferred embodiment, the body of the air mover is comprised of an axial fan 40 encased between a fan housing 36 and a cover plate 38, each having symmetrically spaced cutouts of quarter circles with progressively larger diameters that serve as openings for the air to be drawn in and expelled out by the axial fan 40. The dimensions of these cutouts are such as to maximize the airflow from the axial fan, while preventing injury from accidental contact with the fan blades. The fan housing 36 and cover plate 38 are held together by means of four screws 42 and four nuts 44. In other embodiments, a blower may be used instead of the axial fan 40, with a blower housing and a top plate. The two clevis mounting brackets 34 are joined to the fan housing 36 through tapered holes 48 by means of two pivot screws 46.

Each clevis mounting bracket 34, joined to the fan housing 36 by a pivot screw 46, turns independently as indicated by the arrows and dashed lines in FIG. 4A. This gives the occupant of the chair the ability to direct the airflow toward a desired area of the seat by means of pivoting the air mover 14 while the clevis mounting brackets 34 remain fixed to the restraining links 28, as shown by the arrows in FIG. 4B. Thus, more air can be directed to flow towards the front of the seat to cool the crotch area or towards the back of the seat to cool the posterior.

FIG. 5A through 5D are views of the power supply unit 16 and holster 18. In FIG. 5A, the power supply unit 16 is shown inserted in the holster, while in FIG. 5B the power supply unit 16 is shown outside the holster 18. FIG. 5C is a view of the output side of the power supply unit 16. In the preferred embodiment, the electrical power is delivered on a Type A USB jack through the output port 50. The input side of the power supply unit 16 is shown in FIG. 5D. In the preferred embodiment, a USB mini jack is used to recharge the unit through the input port 52. When the power supply unit 16 is connected to an external power source to recharge it, a light emitting diode (LED) emits red light that is visible through the charging status indicator port 54. Once the power supply is fully charged, green light is visible through the charging status indicator port 54. In the preferred embodiment, the power supply unit is recharged by connecting it to a five volt direct current (DC) source. In other embodiments, an alternating current (AC) source can be used for charging. The power supply unit is designed to be portable, with dimensions that allow it to fit comfortably inside a person's hand. The reason for this is explained in a subsequent paragraph.

FIG. 6 is a block diagram of the circuits used in the preferred embodiment of the present invention. The dashed line delineates the circuits of the power supply unit 60A. A lithium ion battery 60E, protected from over-discharge with a battery protection circuit 60F, produces 3.7 volts on average while discharging. The battery power is applied to a step-up voltage regulation circuit 60G to convert the 3.7 volts average discharge voltage of the battery into five volts of regulated power. The regulated voltage is supplied at the output connector 60H. A fully charged battery in the preferred embodiment stores 8.9 Watt-hours of energy, which is sufficient to power the air mover of the preferred embodiment for eight hours. When the battery charge is exhausted, the power supply unit of the preferred embodiment can be recharged through the input connector 60B by connecting it to any five volt DC power source, such as a USB port on a computer. At the initiation of the charging cycle, a LED 60C emits red light, indicating that the battery is charging. The charging of the battery is via either a constant current or a constant voltage, which are controlled by the charging circuit 60D. When the battery is fully charged, the LED turns green. The amount of electrical power available at the load 62 can be reduced through the control switch circuit 64, which in turn reduces the airflow generated by the air mover. When the power at the load 62 is reduced beyond a certain minimum point, the air mover turns off.

A load 62 can also be connected directly to the output connector 60H, bypassing the control switch circuit 64. The utility of this will be readily apparent to the modern day office worker who is usually equipped with handheld communication and computing devices. Examples of such devices are smartphones and tablet computers sold under the IPHONE, IPAD, BLACKBERRY, SAMSUNG GALAXY and other trademarks. The power supply unit in the preferred embodiment of the present invention is designed to deliver the voltages required to charge these types of devices on its output connector 60H. Thus, instead of using the power supply unit to operate the air mover, an office worker can use it to recharge portable electronics. To make the power supply unit convenient to transport, it was designed with physical dimensions that allow it to fit comfortably in a person's hand.

In summary, the invention disclosed herein is a system for providing personal comfort, by ventilating and cooling the occupant of an AERON office chair. The system mounts conveniently underneath the seat of the chair. The air mover dissipates body heat from the occupant's posterior and crotch regions through the air permeable seating surface of the chair. A power supply unit containing a long lasting, lithium ion battery and various electronic circuits delivers electrical power to the system's air mover. The power supply unit of the system is portable and can be used to charge handheld communication or computing devices, such as smartphones or tablet computers. Given the popularity of AERON office chairs, the present invention has the potential to provide a number of office workers with additional comfort in the workplace.

Claims

1. A ventilation and cooling system for an AERON office chair comprising: an air mover attached to the chair;a power supply unit;a control switch.

2. The system as recited in claim 1, wherein the airflow from the air mover can be pointed in a preferred direction.

3. The system as recited in claim 1, wherein the power supply unit resides on the chair.

4. The system as recited in claim 1, wherein the power supply unit is rechargeable.

5. The system as recited in claim 1, wherein the power supply unit is capable of charging handheld communication and computing devices.

6. A method for cooling a person seated in an AERON office chair by increasing the dissipation of the person's body heat as follows: attaching an air moving device to the chair;providing the means to power and control the air moving device;directing airflow from the air moving device at the person seated in the chair.