Heat-accumulating heater

Abstract

A heat-accumulating heater includes a powdery paraffinic latent heat storage substance sealed in a bag-shaped container. The bag-shaped container includes a plurality of inner container members formed of sheets impermeable to the heat storage substance and water and permeable to air. The inner container members are each received in one of first substantially rectangular outer container members made of rubber that are connected to each other in a row so as to be bendable relative to each other. An air layer is present between each inner container member and the corresponding first outer container member, thereby preventing the inner container member from being pressed against the first outer container member. The first outer container members are in turn received in a second outer container member made of cloth.

Description

BACKGROUND OF THE INVENTION[0001]This invention relates to a heat-accumulating heater including a latent heat storage material and used for health and medical purposes such as in thermotherapy for heating part of a human body.[0002]Heat-accumulating heaters, which are also called hot compressions or hot packs, applies heat to the surface of a human body, thereby increasing the bloodstream and suppressing pain. Recent studies also revealed that they can increase the body muscle mass. Such heat-accumulating heaters can be used, for example, for rehabilitation after disease, care for the elderly, and maintenance of the body muscle mass before and after sports activities.[0003]Heat-accumulating heaters or hot packs are controlled under the pharmacy law in Japan as medical appliances. More specifically, they are classified as general medical appliances (class 1) or controlled medical appliances (class 2). These hot packs can be sold only after investigation as to their adaptability and v...

AI Technical Summary

Benefits of technology

[0017]With this arrangement, because the powdery paraffinic latent heat storage substance in the inner member is isolated from water outside the container by the sheet forming the inner container member, the paraffinic latent heat storage substance is always kept dry and its fluidity is never impaired by moisture. Because the air in the inner container member communicates with the exterior of the container, even when heating and heat release are repeated, the air pressures inside and outside the inner container member are kept equal. This prevents the paraffinic latent heat storage substance from being compacted due to a pressure difference between inside and outside the inner container member, thus preventing impairment of its flowability.

[0018]The outer surface of the inner container member is always exposed to the air between the inner and outer container members. This increases air permeability of the inner container member. The outer container member may not be air permeable if it is made of a material that allows completely airtight seal. But practically, in view of the cost, the outer container member is made of an air-permeable material. In order to positively ensure air permeability, vent holes of a suitable size may be formed in the outer container member.

[0021]With this arrangement, because the paraffinic latent heat storage substance is held in the inner container member so as to be freely flowable, and further held by the elastically deformable outer container member, the entire heater can be sufficiently elastically deformable under the pressure from e.g. skin. Thus, the heat-accumulating heater according to the present invention is soft to the touch.

[0022]The heat-accumulating heater according to the invention is flexible as a whole, and can be deformed along any contour of the affected area. This makes it possible to maximize the heat transfer area, and improve fitting and cushioning properties.

Problems solved by technology

Because hot packs are produced under strict quality control and technical control, technical glitches or quality deficiencies are rare compared to other ordinary products.

Thus, the heat storage material tends to shift in the container in the gravitational direction, thus making it difficult to cover a wide area of a human body with the heater, irrespective of the position of the human body.

But in this case, when the paraffinic latent heat storage substance is formed into powder particles and hermetically sealed in a container in the form of a small bag, and then the hot pack is used in an air-tightly sealed state while preventing absorption of moisture, heated and expanded air in the container tends to gradually leak from the container during repeated heating and heat release.

Thus, flexibility of the hot pack is lost, which makes it difficult to apply the hot pack on an affected area of a human body so as to be deformed along the contour of the affected area.

Images