Powered wheeled computing workstation

Abstract

A wheeled workstation comprises: an electric power outlet; and a power housing. The power housing includes a housing body having an inverter compartment for housing an inverter; a battery compartment for housing a battery; and a partition within the housing body for separating the inverter compartment and the battery compartment with the battery compartment above the inverter compartment; wherein the power housing further includes a power inverter having an air intake and a fan for drawing air into the power inverter via the air intake; and wherein the inverter compartment surrounds the power inverter and forms an intake plenum from which it draws air such that the velocity of air passing through the plenum is substantially lower than the velocity of air passing through the air intake.

Description

[0001] Powered Wheeled Computing Workstation

[0002] Field of Invention

[0003] The present invention relates to a wheeled workstation which is arranged to be able to supply AC power to electric outlets on the workstation even while the workstation is not itself plugged into the Mains electricity supply.

[0004] Backg round

[0005] Wheeled workstations permit a person to move the workstation from one location to another, and any equipment on the workstation such as a computer, monitor, printer, dock, Wi-Fi access point and the like move with the workstation so that the person can carry out their work in multiple locations. Some of the equipment carried on the workstation requires an AC power source which is supplied by one or more AC power outlets on the workstation and which supplies AC power even when the workstation is not itself plugged in. While the workstation may be plugged into a Mains power supply when one is readily available, most of the time, it does not need to be plugged in because it includes a DC battery which is charged from the Mains electricity supply, but which supplies AC power to the equipment on the workstation via an inverter and the AC power outlet. This permits the person to move the workstation to locations where there is no Mains power supply but still use the equipment on the workstation, and to move from location to location without having to worry about plugging the workstation in at each location.

[0006] A workstation like this is particularly useful in hospitals where an administrator can move their workstation to the location of a patient in order to enter personal information about the patient into their computer, or where a clinician can move their workstation to the location of the patient to enter patient observations and to view the medical records of the patient using a computing device while at their bedside. A clinician might also have special monitoring, diagnostic or therapeutic equipment located on the wheeled workstation, such as a blood pressure monitor, ultrasound imaging equipment, or a patient vital signs monitor.

[0007] A workstation like this is also useful in industrial settings where a worker can move their workstation from one location to another in order to record information about an industrial process occurring in different places within the industrial setting. The workstation might carry specialist equipment which can be used in multiple locations by virtue of the fact that it is located on a wheeled workstation, or a label printer and scanner for use in managing inventory. Another use is for the workstation to give access to technical information, such as technical manuals. Although wheeled workstations of this kind have become popular, there are some significant problems with them. For example, the battery and the inverter tend to be very heavy, and so they are located together in the base of the wheeled workstation for reasons of stability. Since the inverter tends to get hot, it requires active cooling using a fan. To avoid objects or liquids being dropped or spilt into an inlet to the fan, the fan inlet faces downwards towards the ground within the base where dust and dirt tend to be ingested. A robust cleaning program is necessary to ensure that the fan inlet does not get blocked with dust and dirt causing the inverter to overheat. Not only does the overheating deleteriously affect the operation of the battery, but, since dirt and dust accumulates in the fan inlet and on the inverter, it is known for wheeled workstations of this kind to catch fire.

[0008] An aim of the present invention is to reduce the chances of overheating and to enable safer operation of such a wheeled workstation.

[0009] Summary of Invention

[0010] According to a first aspect of the invention, a wheeled workstation comprises: an electric power outlet arranged to supply AC power; and a power housing including a housing body having : an inverter compartment for housing an inverter; a battery compartment for housing a battery which is front-ventilated; and a partition within the housing body for separating the inverter compartment and the battery compartment with the battery compartment above the inverter compartment; wherein the power housing further includes a door arranged to close the front of the battery compartment such that it is spaced from the front of the battery compartment to define a passive air passage, and wherein there is an air vent at the top of the door and an air vent at the bottom of the door so as to permit ambient air to flow up through the passive air passage. This aspect of the invention permits passive airflow to be induced by heat within the battery compartment or within the passive air passage such that heat is carried away from the battery compartment.

[0011] The air vent at the top of the door is preferably a gap between the top of the door and the housing because it does not require additional parts to be assembled. The air vent at the bottom of the door is preferably a gap between the bottom of the door and the housing because it does not require additional parts to be assembled.

[0012] In one arrangement, the battery compartment is open-fronted, but in another, the front of the battery compartment includes a ventilation grill. The passive air passage is advantageously defined by the door closing the front of the battery compartment being upright because warm and hot air naturally rises so as to induce the airflow up through the passive air passage. The door might include edges which close against the housing body.

[0013] The power housing may further comprise a heat sink plate disposed beneath the partition wherein the power housing further includes a power inverter mounted on the heat sink plate.

[0014] Advantageously, the heat sink plate has an depressed region or area corresponding to the battery position spaced from the partition to form an air gap, the heat sink including an inverter mount to which the power inverter is mounted to the heat sink plate.

[0015] Preferably, the partition includes a vent outside of the battery position for allowing hot air within the air gap to be released into the battery compartment.

[0016] The power housing may further include a power inverter having an air intake and a fan for drawing air into the power inverter via the air intake; and wherein the inverter compartment surrounds the power inverter and forms an intake plenum from which it draws air such that the velocity of air passing through the plenum is substantially lower than the velocity of air passing through the air intake. The intake plenum is preferably downwardly open whereby the air is drawn into the intake plenum from underneath. The power inverter might further include an air exhaust, and the inverter compartment forms an exhaust plenum into which it exhausts air such that the velocity of air passing through the plenum is substantially lower than the velocity of air passing through the air exhaust.

[0017] According to a second aspect of the invention, a power housing of a wheeled workstation comprises: an inverter compartment for housing an inverter; a battery compartment for housing a battery at a battery position within the battery compartment; a partition within the housing body for separating the inverter compartment and the battery compartment with the battery compartment above the inverter compartment; and a heat sink plate disposed beneath the partition with an area corresponding to the battery position spaced from the partition to form an air gap, the heat sink including an inverter mount to which a power inverter can be mounted to the heat sink plate. This has the advantage that heat is conveyed from the inverter to the housing body via the heat exchanger with the air gap insulating the battery from the heat exchanger. This improved cooling means that during discharge of the battery via the inverter, the inverter does not require its cooling fan to be switched on, which reduces the consumption of power from the battery and extends the battery life by several hours. The reduction in charging cycles also means that a battery will not require replacement so frequently.

[0018] The partition advantageously includes a vent outside of the battery position for allowing hot air within the air gap to be released into the battery compartment.

[0019] Preferably, the battery compartment is ventilated.

[0020] According to a third aspect of the invention, a power housing of a wheeled workstation comprises: an inverter compartment for housing an inverter; a battery compartment for housing a battery; and a partition within the housing body for separating the inverter compartment and the battery compartment with the battery compartment above the inverter compartment; wherein the power housing further includes a power inverter having an air intake and a fan for drawing air into the power inverter via the air intake; and wherein the inverter compartment surrounds the power inverter and forms an intake plenum from which it draws air such that the velocity of air passing through the plenum is substantially lower than the velocity of air passing through the air intake. This has the advantage that less dust and dirt is drawn into the air intake of the inverter.

[0021] Preferably, the intake plenum is downwardly open whereby the air is drawn into the intake plenum from underneath.

[0022] In the preferred embodiment, the power inverter further includes an air exhaust, and the inverter compartment forms an exhaust plenum into which it exhausts air such that the velocity of air passing through the plenum is substantially lower than the velocity of air passing through the air exhaust. This has the advantage that the exhausted air is less likely to disturb or entrain dirt or dust on the floor beneath the wheeled workstation.

[0023] According to a fourth aspect of the invention, a wheeled workstation comprises an electric power outlet arranged to supply AC power; and a power housing according to any of the first, second or third aspects of the invention.

[0024] According to a fifth aspect of the invention, a method of cooling an inverter of a power housing of a wheeled workstation of the first aspect of the invention, comprises inducing the flow of air up through the passive air passage such that heat is carried away from the battery compartment. According to a sixth aspect of the invention, a method of cooling an inverter of a power housing of a wheeled workstation of the second aspect of the invention, comprises the conveying of heat from the inverter to the housing body via the heat exchanger with the air gap insulating the battery from the heat exchanger.

[0025] According to a seventh aspect of the invention, a method of cooling an inverter of a power housing of a wheeled workstation of the third aspect of the invention comprises the drawing of cooling air from the intake plenum such that the velocity of air passing through the plenum is substantially lower than the velocity of air passing through the air intake.

[0026] Brief Description of the Drawings

[0027] The present disclosure will now be described by way of example only with reference to the accompanying drawings in which:

[0028] Figures 1 and 2 are isometric views of a wheeled workstation with a power housing in accordance with an embodiment of the present invention;

[0029] Figure 3 is a view of the power housing shown in Figure 1;

[0030] Figure 4 is an isometric view of the power housing of Figures 1 to 3 with its door removed; Figure 5 is a front view of the housing body of the power housing if Figures 1 to 4;

[0031] Figure 6 is a sectional side view of the power housing of the embodiment shown in Figures 1 to 5; and

[0032] Figure 7 is an underside view of the power housing shown in Figures 1 to 6.

[0033] Detailed Description

[0034] An embodiment of the present invention will now be described by way of example. Referring to Figures 1 & 2, a wheeled workstation 1 includes a wheeled base 2, an upright 3 extending from the wheeled base 2 on which a worktop 4 is carried on which equipment such as a computer (not visible), monitor 6, printer, dock, Wi-Fi access point diagnostic equipment and the like may be used. The workstation 1 also includes one or more AC power outlet (not visible) on or close to the worktop so that the equipment can be plugged to receive AC power to operate it. It is preferred that the upright 3 extending from the wheeled base 2 to the worktop 4 can be varied in its length in order to allow a user to adjust the height of the worktop 4. The wheeled workstation also includes a power housing 10 carried by the upright, which feeds electrical AC power to the AC power outlet. In an alternative embodiment, the power housing could be carried by the wheeled base 2. Referring now to Figures 3 to 7, all of which show the power housing 10, the housing 10 includes a housing body 11 having three compartments, one arranged above another. The bottom compartment is an inverter compartment 12, above which is located a battery compartment 13, above which is located an upper compartment 14. These compartments are separated by partitions. A lower partition 15 separates the inverter compartment 12 from the battery compartment 13. An upper partition 16 separates the battery compartment 13 from the upper compartment 14. The partitions are substantially level and are supported from, and form part of, the housing body 11. The lower partition 15 has a heat sink plate 17 bolted or otherwise attached to its underside, a central depressed region or part of which is spaced from the lower partition 15 to leave an air gap between them. The air gap is disposed beneath the lower partition 15 in a position corresponding to the area on which the battery stands - the battery area. The lower partition 15 includes an opening 19 which allows the air within the air gap 18 to communicate with the air within the battery compartment 13.

[0035] A power inverter 20 is bolted or otherwise attached to the underside of the heat sink plate 17 such that the heat sink plate conducts heat generated by the power inverter 20 to the housing body. It should be understood that the power inverter 20 is the component within the workstation which tends to generate the most heat, and so cooling it is a key part of this invention.

[0036] The battery compartment contains a battery 21 which stands on the lower partition 15, and is secured in place there by means which are not shown. In this case, the battery is a lithium iron battery, but the type of battery is not important here. The power inverter 20, the battery 21, and the AC power outlet (not shown) are all electrically connected, but these connections are not shown in this specification because it is the structure which is important to this invention rather than the electrical connections, which are known from existing products.

[0037] The battery compartment 13 is shown in Figure 4 to be closed by a removable panel with a ventilation grill. In Figures 5 & 6 the battery compartment 13 and the upper compartment 14 are open-fronted in order to allow access to the battery 21. The upper compartment 14 is open-fronted to allow easy access to it for storage of items, such as a computer, AC power outlets and any other thing. In contrast, the inverter compartment includes a front panel 22 extending downwardly from the lower partition 15 in order to ensure that the power inverter is surrounded on all sides. An outwardly directed lip 23 is located at the bottom of the front panel 22. The front of the power housing is closed by a housing door 25 which is hinged at a pivot 26, towards its bottom end, with the housing body 11. In Figure 2, the housing door 25 is shown partially open, but it will be realised from that, once it is closed, it will be generally upright with the top edge 27 of the housing door 25 close to the housing body 11. The housing door 25 can be locked closed to prevent unauthorised access to the contents of the power housing 10. When closed, there is an air gap between the top edge 27 of the housing door 25 and the top of the housing body 11, and the bottom of the housing door 25 is open. The housing door 25 is spaced from the compartments to form a passive air passage 32 which allows the passage of air upwards behind the door but in front of the three compartments to effect passive cooling for the battery 21 and any items stored within the upper compartment 14. It should be appreciated that a user might place electrical items within the upper compartment 14 which might generate heat. Any heat from the battery 21 or from the contents of the upper compartment 14 will rise into the passive air passage, and rise through the passive air passage 32. This will establish a convection air current which induces an airflow into the passive air passage 32 from the open bottom of the housing door 25, upwards through the passive air passage 32 and out through the gap between the top edge 27 of the housing door 25 and top edge of the housing body 11.

[0038] From Figure 1, it can be seen that the power inverter 20 is located within the inverter compartment 12, with plenty of space around it for cooling and for the flow of air. The power inverter 20 includes an air intake 35 which draws air from the space at one end of the power inverter 20, which is described here as an intake plenum 30 because, although the air within the intake plenum 30 is at ambient pressure, the power inverter 20 draws air into the air intake at a relatively high velocity compared with the velocity of the airflow through the plenum so that any dust or dirt beneath the plenum 30 is unlikely to be entrained in the airflow. To achieve this relatively lower airflow through the intake plenum, the cross-sectional area of the intake plenum perpendicular to the direction of the airflow is at least double the cross-sectional area of the air intake 35, and preferably at least three times the cross-sectional area. The power inverter 20 also includes an air exhaust 36 which includes a fan which draws air through the power inverter from the intake plenum 30 and the air intake 35, and blows it out through the air exhaust 36 and into a space around the air exhaust 36 described here as an exhaust plenum 31. The exhaust plenum 31 has a relatively large volume such that the air exhausted downwardly out of the exhaust plenum is exhausted at a lower velocity than the velocity of the air exhaust through the air exhaust, thereby minimising the amount of dust and dirt which might be disturbed on the ground below. To achieve this relatively lower airflow through the exhaust plenum, the cross-sectional area of the exhaust plenum perpendicular to the direction of the airflow is at least double the cross-sectional area of the air exhaust 36, and preferably at least three times the cross-sectional area.

[0039] The structure described has a number of improved features. Firstly, separating the power inverter from the battery by locating them on opposite sides of a partition significantly reduces the extent to which the power inverter 20 heats the battery 21. It should be understood that the power inverter 20 has two operating functions. It's first function is to receive mains AC power when the workstation is plugged in, and to generate DC electricity which is used for charging the battery 21. This is when the power inverter 20 gets hottest because this is when it is handling the most current. The hotter the battery is, the slower it charges, the greater it deteriorates during charged and discharging, and the lower its capacity when it is charged. Its second function is to take DC power from the battery 21 and to send AC electricity to the AC power outlet for use by a user who is using electrical equipment on the workstation, particularly when the workstation is not plugged in to the Mains AC power. Heat is generated by the power inverter 20 during this operation as well as during battery charging, but it tends to be less than the heat generated during charging. Heating of the battery during the charging operation and the discharging operation is minimised : by locating the power inverter 20 and the battery 21 in different compartments separated by the lower partition 15; by surrounding the inverter compartment 12 by including a front panel 22 to reduce the amount of hot air from the inverter compartment 12 passing up through the passive air passage 32; by mounting the power inverter 21 on a heat sink plate 17 in order to transfer heat to the housing body 11 which dissipates that heat; and by creating an air gap 18 between the heat sink plate 17 and the lower partition 15 with abattery area corresponding to the area of the lower partition 15 on which the battery stands so that the battery is insulated from the heat sink a passive air passage 32 behind the housing door 25 allowing any heat from the battery 21 and battery compartment 13 to be convected away by passing up through the passive air passage 32, that convected airflow being considerably enhanced by the induced airflow.

[0040] As a result of this cooling, during the second function of generating AC electricity from the battery, the inverter is able to operate without requiring the operation of the fan 36, which increases battery life. Additionally, the battery has a much longer life before it needs replacing, and charges more quickly, because it is operating with much less thermal stress. Another improved feature is the use of the air intake plenum 30 to minimise the amount of dust and dirt entrained in air leading to the power inverter 20. A lesser benefit is from the large volume exhaust plenum 31 which reduces the flow of air exiting the inverter compartment 12 towards the ground. Various further modifications to the above-described examples, whether by way of addition, deletion or substitution, will be apparent to the skilled person to provide additional examples, any and all of which are intended to be encompassed by the appended claims. For example, the embodiment described includes an upper partition 16 which defines the upper compartment 14. In a modified embodiment, the upper partition and upper compartment may be deleted, resulting in a two-compartment housing body which can be more compact. Such a modification remains within the scope of this invention.

Claims

Claims1. A wheeled workstation comprising : an electric power outlet arranged to supply AC power; and a power housing including a housing body having : an inverter compartment for housing an inverter; a battery compartment for housing a battery which is front-ventilated; and a partition within the housing body for separating the inverter compartment and the battery compartment with the battery compartment above the inverter compartment; wherein the power housing further includes a door arranged to close the front of the battery compartment such that it is spaced from the front of the battery compartment to define a passive air passage, and wherein there is an air vent at the top of the door and an air vent at the bottom of the door so as to permit ambient air to flow up through the passive air passage.

2. A wheeled workstation according to claim 1 wherein the air vent at the top of the door is a gap between the top of the door and the housing.

3. A wheeled workstation according to claim 1 or claim 2, wherein the air vent at the bottom of the door is a gap between the bottom of the door and the housing.

4. A wheeled workstation according to any one of the preceding claims wherein the battery compartment is open-fronted.

5. A wheeled workstation according to any one of claims 1 to 3, wherein the front of the battery compartment includes a ventilation grill.

6. A wheeled workstation according to any of the preceding claims, wherein the passive air passage defined by the door closing the front of the battery compartment is upright.

7. A wheeled workstation according to any of the preceding claims, wherein the door includes edges which close against the housing body.

8. A power housing according to any one of the preceding claims, further comprising a heat sink plate disposed beneath the partition; andwherein the power housing further includes a power inverter mounted on the heat sink plate.

9. A wheeled workstation according to claim 8, wherein the heat sink plate has a depressed region, corresponding to a battery area where the battery stands, spaced from the partition to form an air gap, the heat sink including an inverter mount to which the power inverter is mounted to the heat sink plate.

10. A wheeled workstation according to claim 9, wherein the partition includes a vent outside of the battery position for allowing hot air within the air gap to be released into the battery compartment.

11. A wheeled workstation according to any one of the preceding claims wherein the power housing further includes a power inverter having an air intake and a fan for drawing air into the power inverter via the air intake; and wherein the inverter compartment surrounds the power inverter and forms an intake plenum from which it draws air such that the velocity of air passing through the plenum is substantially lower than the velocity of air passing through the air intake.

12. A wheeled workstation according to claim 11, wherein the intake plenum is downwardly open whereby the air is drawn into the intake plenum from underneath.

13. A wheeled workstation according to claim 11 or 12, wherein the power inverter further includes an air exhaust, and the inverter compartment forms an exhaust plenum into which it exhausts air such that the velocity of air passing through the plenum is substantially lower than the velocity of air passing through the air exhaust.

14. A method of cooling an inverter of a wheeled workstation of any one of claims 1 to 13, comprising inducing the flow of air up through the passive air passage such that heat is carried away from the battery compartment.

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