Patent Application
20100132124
This invention generally relates to a pressure controlling system, apparatus and method for an inflatable pad and more specifically to a system, apparatus and method for determining an appropriate pressure of the inflatable pad.
Compared to the conventional bed, the inflatable pad may provide better support to the user and equally distribute the pressure through the whole mattress preventing specific portion from compressed, thus the inflatable pad has been broadly adopted for therapeutic use or healthy care. However, it is necessary to set specific internal pressure for every patient due to his special condition. The nurse needs to re-configure the inflatable pad for each patient, which leads to inefficiency and even affects the quality of medical treatment.
Many solutions are provided to solve the above problems. Huntleigh suggest to externally adding a thin bladder under the mattress. When a patient lies on the mattress, the body weight of the patient will compress the thin bladder and then the internal pressure of the mattress is adjusted according to the measured pressure of the thin bladder. For example, when the pressure in the thin bladder is decreased, the mattress is deflated to lower the internal pressure and vice versa. However, it may not accurately provide an appropriate internal pressure for each user, and an additional bladder means more expensive manufacturing cost.
Gaymer disclosed in U.S. Pat. No. 6,643,694 issued on Sep. 13, 2005 a customized mattress having a bladder inside. A conductive device is disposed on the bladder and when the bladder is deflated or inflated beyond limit, the conductive device is activated and a signal is transmitted to the controller to perform corresponding inflation or deflation. Although the internal pressure may be maintain within a predetermined range by means of Gaymer's proposal, it still fails to accurately provide an appropriate internal pressure for each user, and an additional bladder and complicated conductive device also cause expensive cost.
Hill-ROM disclosed in US Publication 2007/0272450 published on Nov. 29, 2007 an external bladder under mattress for measuring the body weight of the user. Before the use of the mattress, the pressure of the external bladder is increased to a basic pressure. When the patient lies on the mattress, the pump will continue to pressurize the bladder for a fix period. Users with different body weights will lead to different final pressure, by which the body weight will be calculated. Thereafter, the internal pressure of the mattress is configured based on the calculated body weight of the user. Although Hill-ROM's proposal may respectively calculate the internal pressure for each user, however, the calculated result is highly depending on the performance of the pump. Even for the same user, the calculation result will be different if the performance of the pump is changed due to such as manufacturing tolerance or aging problem. Further, once the manufacturer decides to use a new pump model, the entire process need to be performed again entirely. As the above descriptions, Hill-ROM does not provide an accurate result while the additional bladder also increases the manufacturing cost.
Therefore, it will be advantageous to provide a mattress without any additional bladder and an accurate control of the internal pressure of the mattress according to the characteristics of each user. Not only the manufacturing cost can be significantly lowered but the performance of medical treatment can also be improved.
One aspect of the present invention is to provide a system, apparatus and method for controlling an internal pressure of an inflatable pad without additional use of an external bladder or a customized mattress.
Another aspect of the present invention is to provide a system, apparatus and method for precisely controlling an internal pressure of an inflatable pad.
Yet another aspect of the present invention is to provide a system, apparatus and method for determining an appropriate pressure corresponding to users with different characteristics.
Further aspect of the present invention is to provide a easy installation, user friendly and cost efficient system, apparatus and method for controlling internal pressure of an inflatable pad.
A pressure controlling system is disclosed according to one aspect of the present invention. The system includes an inflatable pad and a control apparatus. The inflatable pad has a mattress for supporting a user. The apparatus includes a control valve, a sensor, a driving device and a controller. The control valve is switched between statuses to selectively perform inflation and deflation of the mattress. The sensor measures the internal pressure of the mattress. The driving device is coupled to the control valve to blow air into the mattress. The controller is coupled to the control valve for controlling the internal pressure at a predetermined pressure. Responsive to the present of a user, the controller deflates the mattress within a deflation period and records the internal pressure during the deflation period. A characteristic curve is obtained representing the variation of the internal pressure corresponding to the user and an appropriate pressure is determined based on the characteristic curve.
On the other aspect of the present invention, the mattress further includes at least one first cell and at least one second cell. The control valve further includes at least one first opening, at least one second opening, at least one first outlet opening, at least one second outlet opening and an inlet opening. The control apparatus further includes a hose having a first transport tube connecting the first opening and the first cell and a second transport tube connecting the second opening and the second cell. The inlet opening is coupled to the driving device and the control valve selectively allows the performance of inflation through the first opening and second opening and the performance of deflation through the first outlet opening and the second outlet opening.
Yet another aspect of the present invention, the sensor further includes at least one first sensing unit and at least one second sensing unit for respectively measuring an internal pressure of the first cell and an internal pressure of the second cell.
A method for controlling an internal pressure of a mattress of an inflatable pad according to another aspect of the present invention is disclosed. The method includes the steps of: controlling the internal pressure of the mattress to a predetermined pressure; upon the present of a user, deflating the mattress within a deflation period; recording a variation of the internal pressure during the deflation period; obtaining a characteristic curve corresponding the user; comparing the obtained characteristic curve to a database containing a plurality of characteristic curves corresponding to persons with a plurality of mass distributions; and determining an appropriate pressure corresponding to the user based on the comparison.
Other objects and advantages of the present invention will become apparent from the following descriptions, taken in connection with the accompanying drawings, wherein, by way of illustration and example, several embodiments of the present invention are disclosed.
The drawings constitute a part of this specification and include exemplary embodiments of the invention, which may be embodied in various forms. It is to be understood that in some instances, various aspects of the invention may be shown exaggerated or enlarged to facilitate an understanding of the invention.
Further details of the pressure controlling processes are described hereinafter for those who skilled in the art to clearly understand the embodiments of the present invention.
When the user is ready, the controller 320 controls the control valve 310 to deflate the mattress 210 within a deflation period and records a variation of the internal pressure during said deflation period. For an exemplary purpose, two methods, namely constant duration method and target pressure method, may be embodied during the deflation period depending on the design choices or practical preferences, which are not limited. For constant duration method (step 362), the controller 320 will use a constant duration of deflation period for every users, and records the internal pressure of mattress 210 at the end of the deflation period. Thereafter, a characteristic curve corresponding to said user is obtained (step 366). Please refer to
Alternatively in the target pressure method (step 364), the controller 320 will set a target value of the internal pressure instead of constant duration. The deflation period will end at the time the measured internal pressure equals to the target pressure. At that time, the duration of deflation period will be recorded and the characteristic curve corresponding to the user is obtained (step 366). Please refer to
Generally speaking, users with identical body weight may still have different body shapes, which will lead to different appropriate pressure of the mattress 210. For example, a user may have pear shape of his body and the weight distribution is concentrated at two ends of the inflatable pad 200. Even with the same body weight, however, another user may have an apple shape of his body and the weight distribution is then concentrated in the central portion of the inflatable pad 200. Moreover, height of a user also affects the weight distribution. Determining the internal pressure merely based on the body weight of the user may not provide an appropriate result, which actually fits the user with specific characteristics. Even though some conventional method tends to solve this problem by detecting user's characteristics with more complicated equipments, it leads to expensive cost and complicated operation process. According to particular embodiments of the present invention, users with different body shapes are distinguishable and a better effect compared to the conventional solutions may be provided. Further, simple design also reduces the entire cost according to the embodiments of the present invention. Please refer to
Although the embodiment of the present invention uses a driving device such as a pump to perform inflation of mattress 210, however, the appropriate pressure is determined by the characteristic curve obtained during the deflation process and is independent of the actual power of the pump. Even if the pumps are significantly different from each other due to manufacture tolerance or aging problems whatsoever, it only affects the time prior to the internal pressure reaching the predetermined pressure while the measurement and generation of characteristic curve will not be affected. Basically, the deflation process is mainly depending on the diameter of the outlet opening of the control valve 310. Those who skilled in the art may understand that the manufacture tolerance and aging problem occurred (if any) in the outlet opening of the control valve 310 are significantly minor as compared to those in the pump, and therefore the measurement result may be accurately obtained. As to the case that the manufacturer desires to use a new pump model with different diameter of opening, the database may be applied merely after some minor revisions, which is considerably easy, inexpensive and accurate. In a preferred embodiment of the present invention, the inner diameter of the outlet opening of the control valve 310 is between about 0.1 mm to about 30 mm. It should be noted that a bottleneck other than the outlet opening thorough the air flowing path may be controlled to achieve the substantially similar deflation process. For example, in an alternative embodiment, the diameter of outlet opening of the control valve 310 may be 40 mm while the inner diameter of the hose 335 may be controlled within the preferred range to obtain a substantially similar result. Those who skilled in the art shall understand the location of the bottleneck may be decided according to manufacturing selection in view of engineering and/or business considerations.
The sensor 325 further includes a first sensing unit 322 and a second sensing unit 324 respectively disposed on the first opening 312 and second opening 314 of the control valve 310 for respectively measuring the internal pressure of the first cell 211 and the second cell 212. Therefore, the embodiments of the present invention may determine appropriate pressure respectively for each cell. Each cell may be designated for its preferred pressure based on the characteristics of the user, which may lead to better result and more comfortable experience. In other words, the sensor 325 may include the sensing units each corresponding to one cell to determine the pressure therein in this embodiment. In another embodiment, the number of the sensing units needs not to be identical to that of the cells. For example, the sensor 325 may have only one sensing unit 322 connected to both the first cell 211 and the second cell 212. The sensing unit 322 may alternately measure the pressure of the first cell 211 and the second cell 212.
As mentioned above, it is disclosed a system, apparatus and method for controlling an internal pressure of an inflatable pad without additional use of an external bladder or a customized mattress. The user merely needs to connect the control apparatus to the mattress and the appropriate pressure of the mattress may be automatically and accurately determined. Furthermore, it is also easy for installation, user friendly and cost efficient, which may provide a really competitive solution compared to the prior arts.
Detailed descriptions of the preferred embodiments are provided herein. It is to be understood, however, that the present invention may be embodied in various forms. Therefore, specific details disclosed herein are not to be interpreted as limiting, but rather as a basis for the claims and as a representative basis for teaching one skilled in the art to employ the present invention in virtually any appropriately detailed system, structure or manner.
