Patent Application
20180311070
The present invention relates to a cooling pad for medically cooling regions of the body of a person thereby reducing the body temperature in said regions.
Cooling pads may be used in medical cooling processes for medically cooling various regions of the body of a person or patient in a non-invasive manner by placing the cooling pad onto or around the body part to be cooled. For example, a cooling pad may be employed to cool regions of the head or neck of a person who has suffered from stroke or to a concussion of the brain. Cooling pads may also be applied to cool the head of a person who is receiving chemo-therapy treatment in order to minimize the loss of hair which often is a result of the treatment.
A cooling pad typically consists of two superimposed sheets of flexible, fluid tight material that are sealed together along their edges. An inlet port is arranged in one end of the cooling pad for letting a flow of cooling fluid, e.g. liquid, into the pad and an outlet port is provided in another end allowing the flow of cooling liquid out of the pad.
A problem related to cooling pads is that the flow of cooling fluid may be unevenly distributed over the cooling pad and thereby resulting in a non-uniform and inefficient cooling effect.
This problem has been addressed in U.S. Pat. No. 4,138,743 which discloses a cooling pad to be applied on the head of a person. The cooling pad is divided into sections for cooling different portions of the head of the wearer of the pad, whereby each section comprises a plurality of flow passageways for distributing the cooling liquid over the respective section. However, due to the shape of the different sections of the cooling pad, the flow of liquid in the flow passageway may stagnate in certain regions of the cooling pad and result in a low cooling effect of the cooling pad.
U.S. Pat. No. 5,086,771 shows a further cooling pad having flow guiding means.
Thus, it is an object of the present disclosure to provide an improved cooling pad to be applied on portions of the body of person which solves or at least mitigates one or more of the problems of the prior-art. In particular, it is an object of the present disclosure to provide a cooling pad with increased cooling effect.
According to a first aspect of the present disclosure at least one of these objects is achieved by a cooling pad for use in a non-invasive medical cooling process for cooling at least one portion of the body of a person by means of a cooling fluid flowing through the cooling pad in use. The cooling pad comprises:
a bottom sheet and a top sheet of flexible and fluid tight material;
an outer wall extending along the edges of the bottom and top sheets;
an inlet opening for a flow of fluid and an outlet opening for a flow of fluid; characterized in,
at least one inner wall extending within the outer wall, wherein said inner wall is arranged such that a continuous flow channel for conveying fluid in a flow direction from the inlet opening to the outlet opening is formed between the outer wall, the inner wall and the bottom and top sheets, and;
at least one flow guide for guiding a portion of a flow of fluid in the flow channel towards one of the inner wall or outer wall, wherein said at least one flow guide is an elongate straight element and comprises a first end and a second end, and wherein the flow guide is arranged in the flow channel such that the second end is directed towards one of the inner wall or the outer wall of the flow channel and such that the second end is arranged downstream of the first end 41 with respect to the flow direction and such that the flow guide forms an acute angle with a centre axis extending through the flow channel.
The cooling pad of the present disclosure comprises a continuous flow channel which is formed between an outer wall extending along the edges of the cooling pad and an inner wall located within the outer wall. The flow channel thereby provides a unidirectional flow of fluid, i.e. a flow of fluid which essentially follows one single flow path from an inlet opening to an outlet opening of the cooling pad. Thereby are regions of stagnant fluid minimized in the cooling pad.
Typically, the flow of fluid in a flow channel is strongest in the centre of the channel and decreases towards the walls of the channel at which the flow may be stagnant. In the cooling pad according to the present disclosure the difference in flow rate across the flow channel is equalized by the provision of at least one flow guide which is extends oblique in downstream direction of the flow channel towards one of the walls. The flow guide thereby directs a portion of the strong flow of fluid in the centre of the flow channel towards the stagnant regions in the vicinity of the outer and inner walls. In summary, the provision of a unidirectional flow of fluid through the cooling pad and the equalizing effect provided by the flow guide on the flow of fluid across the flow channel results in that an even and effective cooling effect is achieved by the cooling pad according to the present disclosure. In addition thereto, the provision of the flow guide may further cause a turbulent fluid flow which also increases the cooling effect.
The cooling fluid may be any cooling medium suitable for conducting the medical cooling of the person or patient, e.g. a cooling liquid or a cooling gas.
Further alternatives of the present disclosure are disclosed in the appended claims and the following detailed description.
The cooling pad according to the present disclosure will now be described more fully hereinafter. The cooling pad according to the present disclosure may however be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided by way of example so that this disclosure will be thorough and complete, and will fully convey the scope of the present disclosure to those persons skilled in the art. Same reference numbers refer to same elements throughout the description.
The cooling pad according to the present disclosure is hereinafter described with reference to a cooling pad configured for cooling portions of the head and neck of a person. However, it appreciated that the cooling pad according to the present disclosure alternatively may be configured for cooling other portions of the body of a person. For example, the cooling pad according to the present disclosure may be configured for cooling of the torso, or the back, or the legs, or the arms of a person.
The cooling pad 100 comprises a bottom sheet 10 and a top sheet 11 (which only partially is shown in
Thus, the cooling pad 100 further comprises at least one inner wall 21. The inner wall 21 is arranged within the outer wall 20, and between the bottom- and top sheets 10, 11 The inner wall 21 divides the opening in the outer wall 20 in an inlet opening 22 for introducing a cooling fluid into the cooling pad and an outlet opening 23 for discharging fluid from the cooling pad. The inner wall 21 further extends within the cooling pad, at predetermined distances from the outer wall 20, such that a continuous flow channel 200 is achieved between the outer and inner walls 20, 21, from the inlet opening 22 to the outlet opening 23.
The flow direction from the inlet opening to the outlet opening is indicated by the dashed arrow 205. The dashed arrow 205 also marks the centre of the flow channel 200, thus it constitutes the centre axis 205 of the flow channel. The centre axis 205 extends in the longitudinal center of the flow channel through out the length of the flow channel and divides the flow channel in longitudinal direction into two opposite halves which have the same width.
When the cooling pad has a complex shape, such as shown in
The cooling pad 100 of the embodiment shown in
Turning to
An advantage with the specific form of the cooling pad 100 according to the disclosure is that, when applied on to the head and neck of a person, it follows the form of the persons head very tightly and without wrinkles. This promotes heat transfer between the cooling pad and the head of the person.
Returning to
The flow guide 40 is oriented in the flow channel 200 such that its second end 42 is directed towards one of the outer wall 20 or the inner wall 21 and such that the second end 42 is positioned downstream first end 41. In other words, the flow guide 40 is oriented obliquely in respect to the flow of fluid in the flow channel 200 and will deflect the flow of fluid in downstream direction and towards the outer- or inner wall 20, 21.
The degree of oblique orientation of the flow guide 40 depends on the flow conditions in the flow channel and has to be determined for each particular case. However, the flow guide 40 forms an acute angle with the centre axis 205 of the flow channel. Preferably, the angle between the flow guide and centre axis is 30°-60°.
The flow guide 40 may be arranged such that it extends across the centre axis 205 extending through the flow channel 200 (not shown in
However, as shown in
The predetermined distance of the first end 41 of the flow guide 40 from the centre axis 205 is selected in dependency of the flow conditions that prevails in the flow channel 200.
The second end 42 of the flow guide is also positioned at a predetermined distance from the outer wall 20 or the inner wall 21. Also the position of the second end 42 of the flow guide 40 is determined in dependency of the flow conditions in the flow channel. It is preferred that the second end 42 of the flow guide is spaced apart from the outer- or inner wall in order to allow a flow of fluid adjacent to the outer- or inner wall.
The cooling pad may comprise a plurality of flow guides 40, arranged in the flow channel 200. By “plurality” of flow guides is meant 2 or more flow guides, such as 3, 4, 5, 10, 30, 50 or more. The plurality of flow guides 40 may be distributed in any suitable manner in the flow channel, for example one or both sides of the centre axis 205.
For example, the cooling pad may comprise , at least one pair of two flow guides 40, arranged side-by-side in the flow channel 200. The flow guides 40 are thereby arranged on opposite sides of the centre axis 205 of the flow channel and oriented such that the second end 42 of a first flow guide 40 is directed towards the inner wall 21 and the second end 42 of a second flow guide 40 is directed towards the outer wall 20. When a pair of two flow guides 40 are arranged side-by side in the flow channel, it is preferred that the each of the first ends 41 of the flow guides are at a predetermined distance from the centre axis 205 in order to allow a flow in the centre of the flow channel.
The cooling pad may comprise a plurality flow guides 40 that are arranged side-by-side on opposite sides of the centre axis 205 in the flow channel 200. It is thereby preferred that the flow guides 40 on one side of the centre axis 205 of the flow channel 200 are off-set axially along the centre axis 205 with respect to the flow guides 40 on the other side of the centre axis 205. This arrangement allows a portion of the strong flow in the center of the flow channel 200 to pass between the flow guides 40 while another portion of the flow is directed to the stagnant region close to the outer- and inner walls 10, 11 of the flow channel 200. The result is a homogenous fluid flow across the flow channel 200.
The flow guides 40 may be evenly distributed throughout the flow channel 200. However, the flow guides 40 are preferably arranged in selected regions of the flow channel 200 where a strong cooling effect is desired. For example, as shown in
The cooling pad 200 according to the present disclosure may manufactured by forming the outer- and inner walls 20, 21 and the flow guides 40 integrally with one of the bottom- or top sheets 10, 11 and then attaching the other one of the bottom- and top sheet 10, 11 fluid tight on top of the outer- and inner walls 20, 21 and on top of the flow guides 40. Integral forming may be achieved by moulding techniques such as injection moulding or form pressing. Fluid tight attachment may be achieved by gluing.
The bottom and top sheets 10, 11 are typically made of silicon. The bottom sheet 10, which typically comprises the outer and inner walls 20, 21 and the flow guides 40 has a thickness of 1.5 mm. The top sheet 11, which in operation is in contact with regions of the head and neck of a person is thinner than the bottom sheet 10 to promote heat transfer and has thickness of 1.10 mm. The outer wall 20, the inner wall 21 and the flow guides 40 are also made of silicon and may have a height of 4 mm. The cooling fluid may typically be a mixture of 80% water and 20% ethylene glycol.
An additional effect of the flow guides 40 and the inner wall 21 is that the number of adherence points between the top and bottom sheets is increased. Thereby, the risk for so-called “ballooning” of the top sheet 11 is greatly reduced. Ballooning may be caused when the flow of fluid is through the flow channel 200 is obstructed within the cooling pad which in turn causes the static pressure to rise in the flow channel. Since the top sheet is made of very thin silicon it yields easily to the increased pressure in the flow channel and causes the cooling pad to swell up like a water balloon. The resulting volume increase causes the poor flow rate and low cooling effect.
Although a particular embodiment has been disclosed in detail this has been done for purpose of illustration only, and is not intended to be limiting. In particular it is contemplated that various substitutions, alterations and modifications may be made within the scope of the appended claims.
For example, to further minimize the risk of ballooning even further it is possible to arrange contact points 50 between the top and bottom sheets 10, 11. The contact points 50 are typically round elements having the same height as the flow guides 40 and the outer and inner walls 20, 21. Of-course, the bottom and top sheets 10, 11 are also fluid tight attached to the contact elements 50.
Preferably, the outlet opening 23 has larger diameter than the inlet opening 22 in order to avoid increase of the static pressure in the cooling pad. Preferably, the diameter of the outlet opening is twice the diameter of the inlet opening.
Moreover, although specific terms may be employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation. Furthermore, as used herein, the terms “comprise/comprises” or “include/includes” do not exclude the presence of other elements. Finally, reference signs in the claims are provided merely as a clarifying example and should not be construed as limiting the scope of the claims in any way.
| Number | Date | Country | Kind |
|---|---|---|---|
| 1551499-5 | Nov 2015 | SE | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2016/078164 | 11/18/2016 | WO | 00 |
