Electrotherapeutic sole and method for making the same

The present invention is to provide an electrotherapeutic sole and a method for making the same, wherein the electrotherapeutic sole is composed of nitrile-butadiene rubber (38%˜42% by weight), conductive carbon black (37%˜42% by weight), a softening oil (14%˜17% by weight), a processing aid (3%˜5% by weight), and an accelerant (1%˜2% by weight) and has a top portion protrudingly provided with a plurality of electrode protuberances that correspond in positions to the acupoints in a human sole; the electrotherapeutic sole is also provided with a socket, thereby an electrotherapeutic pulse output terminal inserted into the socket can send the electrotherapeutic pulses generated by an electrotherapeutic pulse generator sequentially through the socket and the conductive carbon black in the electrotherapeutic sole to the tips of the electrode protuberances to massage the corresponding acupoints in the human sole.

FIELD OF THE INVENTION

The present invention relates to an electrotherapeutic sole and a method for making the same. More particularly, the invention relates to an electrotherapeutic sole that is configured to connect with an electrotherapeutic pulse generator (e.g., a TENS/EMS device) and that does not require a complicated internal circuit in order to send the electrotherapeutic pulses generated by the electrotherapeutic pulse generator to the acupoints in the sole of a human foot.

BACKGROUND OF THE INVENTION

Acupoints, which constitute an important part of the Chinese meridian theories, refer to specific positions on the superficial meridians (i.e., pathways distributed in the human body to facilitate the circulation of life force, or qi, between body organs) that serve as confluences, relay stations, and entrances/exits of qi. When a person falls ill, the corresponding acupoints tend to have such pathological reactions as pain (when pressed), soreness, numbness, nodule formation, and/or swelling. A doctor, therefore, can diagnose a patient's disease according to the pathological reaction(s) taking place and may also treat the patient by stimulating the corresponding acupoints.

Conventionally, acupoints are stimulated by acupuncture or tui na. With the advancement of science and medicine, however, electrotherapy has been a major means of acupoint stimulation, given the fact that acupoints have proved to have low electrical resistance and high conductivity. For example, Dr. Richard Croon of Germany found a relationship between acupoints and the low-resistance points on the skin; Dr. Reinhold Voll, also of Germany, verified the existence of several low-resistance superficial channels in the human body that resemble the meridians in traditional Chinese medicine; and Dr. Yoshio Nakatani of Japan found a relationship between acupoints and ryodoraku, a specific form of acupuncture developed by the Japanese. Electrotherapy is a physical treatment involving electrical stimulation and is conducted as follows. To start with, electrode pads are attached to a patient's skin. Then, a series of current signals generated by an electrotherapeutic signal generator are sent through the electrode pads to the muscle groups under the skin to induce rhythmic yet involuntary partial contraction and relaxation of the muscle groups, thus stimulating the intended acupoints in a way similar to acupuncture.

Electrotherapy is non-invasive, non-pharmacological, and hence an ideal treatment for personal health maintenance at home. Transcutaneous electrical nerve stimulation (TENS) and electrical muscle stimulation (EMS), for instance, are two common methods of electrotherapy nowadays. TENS, which uses low-frequency pulse current to control pain, is based on the “gate control theory”, according to which epidermal nerves (e.g., the Aβ nerve fibers) can be stimulated with weak low-frequency current to generate signals that turn off the “gate” of the corresponding sensory nerves (e.g., the Aδ nerve fibers and the C nerve fibers), thereby stopping the conduction of pain and producing a painkilling effect. EMS, on the other hand, causes muscle contraction and relaxation by stimulating the corresponding motor nerves so that passive physical exercise is carried out for the intended treatment or training. By adjusting the current frequency of the electrotherapeutic signals generated by a TENS or EMS device, therefore, simulated acupuncture can be achieved to stimulate the target acupoints.

However, the inventor of the present invention has found that most of the aforesaid electrotherapeutic instruments use electrode pads as the elements required for transmitting electrotherapeutic signals, and that each time electrotherapy is performed, each target acupoint has to be attached with one electrode pad because the electrode pads generally have a small surface area and must be adhesively and securely attached to all the intended acupoints respectively in order to produce the expected electrotherapeutic effect. Accordingly, multiple electrode pads are needed when it is desired to conduct electrotherapy on several acupoints at the same time, and the electrode pads must be respectively and adhesively attached to the acupoints before the electrotherapy begins so that all the acupoints can receive the therapy at once. It would be very inconvenient if electrotherapy is applied to a plurality of acupoints by turns. The sole of a human foot, for example, has many acupoints and includes reflex areas for almost all the organs in the body. It is common practice, therefore, to manually massage the acupoints in the soles, with a view to stimulating the reflex areas, promoting blood circulation through the body organs, discharging the wastes or toxins in the organs, and thereby enhancing metabolism. But if it is desired to stimulate the acupoints in the soles by electrotherapy instead of manual massage, the electrode pads cause problems. Since each electrode pad covers only a small area, and different parts of a human sole vary greatly in curvature, a large number of electrode pads must be used; nevertheless, it is difficult to firmly attach the electrode pads to all the intended acupoints respectively.

As a solution, shoe soles adapted for electrotherapy were developed, allowing a user's entire foot to stamp on such a sole. These soles are typically provided therein with additional electronic elements (e.g., conductive wires) or are coated with a conductive material such that the manufacturing process is exceedingly complicated. Moreover, when stamped on repeatedly for a long time, the electronic elements are prone to damage (e.g., the conductive wires may be broken), or the conductive material may peel off. In either case, the sole in question will lose its electrotherapeutic effect. Hence, the issue to be addressed by the present invention is to design a novel sole structure that not only has a simple production process, but also is structurally simple to ensure a lasting electrotherapeutic effect during long-term use.

BRIEF SUMMARY OF THE INVENTION

In light of the aforementioned drawbacks of the conventional electrotherapeutic soles, the inventor of the present invention incorporated years of practical experience in the industry into extensive research and repeated tests and finally succeeded in developing the electrotherapeutic sole disclosed herein and a method for making the same. The present invention is intended to provide a better electrotherapeutic sole that will be favored by the general public.

It is an objective of the present invention to provide an electrotherapeutic sole that includes a main body, a plurality of electrode protuberances, and a socket. The main body is a thin plate composed at least of nitrile-butadiene rubber (NBR) at a weight percentage of 38%˜42%; conductive carbon black at a weight percentage of 37%˜42%; a softening oil at a weight percentage of 14%˜17%; a processing aid at a weight percentage of 3%˜5%; and an accelerant at a weight percentage of 1%˜2%. The electrode protuberances are integrally formed with the main body, are distributed over a top portion of the main body, and correspond in positions to the acupoints in a human sole so that when the human sole stamps on the top portion of the main body, the tips of the electrode protuberances are pressed against the corresponding acupoints in the human sole. The socket is provided in the main body. One end of the socket is electrically connected to the electrotherapeutic sole while the opposite end of the socket is formed with an insertion hole. Once inserted into the insertion hole, an electrotherapeutic pulse output terminal can send the electrotherapeutic pulses generated by an electrotherapeutic pulse generator sequentially through the socket, the conductive carbon black in the electrotherapeutic sole, and the tips of the electrode protuberances to the corresponding acupoints in the human sole. Thus, a user only has to stamp on the electrotherapeutic sole, and an acupoint-stimulating effect similar to that achieved by acupuncture will be produced. Moreover, the electrotherapeutic sole can conduct electric current effectively even after long-term use.

Another objective of the present invention is to provide a method for making an electrotherapeutic sole, wherein the electrotherapeutic sole is configured as described above. The method begins by mixing NBR, at a weight percentage of 38%˜42%, thoroughly with conductive carbon black at a weight percentage of 37%˜42%, a softening oil at a weight percentage of 14%˜17%, a processing aid at a weight percentage of 3%˜5%, and an accelerant at a weight percentage of 1%˜2% to form a sheet. The sheet is then placed in the forming space of a forming mold and subjected to compression molding at a forming temperature of 171˜189° C. for 199˜221 seconds. Once the sheet cools down, the electrotherapeutic sole is completed. As the electrotherapeutic sole conducts electric current through the conductive carbon black, there is no need to install additional circuits, and this allows the conductive electrotherapeutic sole to be manufactured rapidly.

DETAILED DESCRIPTION OF THE INVENTION

Referring toFIG. 1andFIG. 2, the present invention provides an electrotherapeutic sole1and a method for making the same. The electrotherapeutic sole1can be used alone or placed in a piece of footwear (e.g., a slipper, sandal, aerobic shoe, or leather shoe) and is configured to be electrically connected to an electrotherapeutic pulse generator2(e.g., a TENS/EMS device). The electrotherapeutic sole1as shown inFIG. 1andFIG. 2is made of a mixture at least of nitrile-butadiene rubber (NBR), conductive carbon black, a softening oil, a processing aid, and an accelerant, wherein the NBR is at a weight percentage of 38%˜42%; the conductive carbon black, 37%˜42%; the softening oil, 14%˜17%; the processing aid, 3%˜5%; and the accelerant, 1%˜2%. In other embodiments of the present invention, additional ingredients may be included to modify the properties (e.g., elasticity, hardness, and/or electrical conductivity) of the electrotherapeutic sole1.

With continued reference toFIG. 1andFIG. 2, the electrotherapeutic sole1includes a main body11, a plurality of electrode protuberances13, and a socket15. The main body11is a thin plate having a thickness of about 1 mm. The electrode protuberances13are integrally formed with the main body11and are distributed over a top portion of the main body11in a way that corresponds to the way in which acupoints are distributed in a human sole. As most people's soles are not entirely flat but are concavely curved on the inner side (where the arch is), the electrode protuberances13in this embodiment vary in height, with those corresponding in position to the arch being the highest; consequently, the maximum thickness of the electrotherapeutic sole1reaches 4.5˜6.5 mm (which is a combined height of the main body11and the electrode protuberances13). The heights of the electrode protuberances13are so designed that when a user's sole stamps on the top portion of the main body11, the tips of the electrode protuberances13are pressed against the corresponding acupoints in the user's sole.

As shown inFIG. 1andFIG. 2, the socket15is provided in the main body11at a position corresponding to the arch of a human sole (i.e., the area indicated by1A inFIG. 1). The socket15has one end electrically connected to the main body11and the opposite end formed with an insertion hole150. The insertion hole150corresponds in position to a lateral edge of the main body11and is configured to be inserted by an electrotherapeutic pulse output terminal21. As conductive carbon black is a semiconductor and has relatively low electrical resistance, the electrotherapeutic sole1is rendered conductive when conductive carbon black is evenly distributed in the electrotherapeutic sole1. Once a user inserts the electrotherapeutic pulse output terminal21of the electrotherapeutic pulse generator2(e.g., a TENS/EMS device) into the insertion hole150, stamps on the top portion of the electrotherapeutic sole1, and turns on the electrotherapeutic pulse generator2, the electrotherapeutic pulses generated by the electrotherapeutic pulse generator2will pass sequentially through the electrotherapeutic pulse output terminal21, the socket15, the conductive carbon black in the electrotherapeutic sole1, and the tips of the electrode protuberances13to the corresponding acupoints in the user's sole, thereby stimulating, or massaging, the acupoints. It should be pointed out that while the socket15in this embodiment is integrally formed with the main body11and corresponds in position to the arch of the human sole, it is feasible in other embodiments of the present invention to design the socket15as a separate unit to be placed at an arbitrary position in the main body11, and the position of the insertion hole150may also be adjusted according to design requirements, provided that the socket15has one end connected to the main body11and the opposite end formed with the insertion hole150for electrical connection with the corresponding electrotherapeutic pulse output terminal21.

The method for making the electrotherapeutic sole1is detailed below with reference toFIGS. 1˜3. First of all, the aforesaid materials (namely the NBR, the conductive carbon black, the softening oil, the processing aid, and the accelerant) are thoroughly mixed to form a sheet (step301). The sheet in this embodiment has a hardness of 57˜63° A (Shore A) and a thickness of 4.5˜6.5 mm. After that, the sheet is placed in the forming space40of a forming mold4(step302). As shown inFIG. 4, the forming mold4includes an upper mold4A and a lower mold4B, and the corresponding areas of the upper and lower molds4A and4B are each concavely provided with at least one sole-molding cavity40A,40B. The sole-molding cavities40A and40B form the forming space40when the upper mold4A and the lower mold4B are put together. In addition, the sole-molding cavity40A of the upper mold4A is concavely provided with a plurality of sunken portions401, and the sole-molding cavity40B of the lower mold4B has a flat bottom wall. In other embodiments of the present invention, however, the constituent parts of the forming mold4may be modified and be different from those described above. The configuration of the sole-molding cavity40B in the lower mold4B may also be modified according to production or design requirements. For example, in cases where the bottom side of the electrotherapeutic sole1is required to be anti-slip, the sole-molding cavity40B may have a wavy or other suitable configuration in order for the bottom side of the electrotherapeutic sole1to have the corresponding configuration.

Referring again toFIGS. 1˜4, the sheet is subjected to compression molding by the forming mold4at a forming temperature of 171˜189° C. for 199˜221 seconds, or until the sheet takes the shape of the forming space40(step303). After the compression molding process, the compression-molded sheet is allowed to cool to complete the electrotherapeutic sole1of the present invention (step304). The electrotherapeutic sole1has a hardness of 57˜63° A (Shore A) and a thickness of 4.5˜6.5 mm. The electrode protuberances13are formed where the sheet corresponds to the sunken portions401, and the bottom portion of the electrotherapeutic sole1has a flat surface due to the configuration of the sole-molding cavity40B in the lower mold4B. Besides, the socket15and the insertion hole150are automatically formed on the electrotherapeutic sole1thanks to the shape of the forming space40of the forming mold4. Since different types of electrotherapeutic pulse output terminals21may vary in configuration (e.g., in length, it is feasible in other embodiments of the present invention to form the desired insertion hole150, or more particularly to adjust the shape and depth of the insertion hole150, by drilling the cooled compression-molded sheet as appropriate, in order for the corresponding electrotherapeutic pulse output terminal21to be securely inserted into the insertion hole150and send the electrotherapeutic pulses generated by the electrotherapeutic pulse generator2(e.g., a TENS/EMS device) through the socket15to the conductive carbon black in the electrotherapeutic sole1and then to the tip of each electrode protuberance13. Now that the electrotherapeutic sole1depends on the conductive carbon black distributed therein, rather than additional electronic circuits conventionally required to be provided in the electrotherapeutic sole, as pathways of current conduction, the electrotherapeutic sole1is exempt from electronic component damage after long-term use, which damage, however, is typical of the conventional electrotherapeutic soles; in other words, the electrotherapeutic sole1of the present invention is expected to have a longer service life than its prior art counterparts.

While the invention herein disclosed has been described by means of specific embodiments, numerous modifications and variations could be made thereto by those skilled in the art without departing from the scope of the invention set forth in the claims.