Note: Descriptions are shown in the official language in which they were submitted.
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This invention relates to an electrocardiographic
electrode for deriving a weak voltage from a person and,
more particularly, to an electrocardiographic electrode
having a structure, in which a water-proof suction member
for covering the electrocardiographic electrode held in
close contact with a person's skin is strongly bonded to
the electrocardiographic electrode so that it will not be
detached therefrorn.
As is well known in the art, electricity generated
in a person is induced by the activity of the heart,
brain, muscles, etc.
Particularly, electricity induced in the heart is
derived and recorded as a weak voltage induced on a
person's skin using an external electrocardiograph. When
the electrocardiograph is used, its input section is
electrically coupled to the person. To this end,
electrocardiographic electrodes have to be held in close
contact with the person's skin.
An object of the invention is to provide an
electrocardiographic electrode, which can solve or
substantially reduce the above problems and permit an
accurate electrocardiogram to be reliably obtained.
According to the invention, there is provided an
electrocardiographic electrode to be held in close contact
with a person's skin for deriving a weak voltaqe from an
inner part of the person comprising a viscous base member
to be held in close contact with the person'e skin and
having a central openin~, a reinforcement member bonded to
the front surface of said viscous base member to close
said opening, a lead connector hook penetrating a central
portion of said reinforcement m~mber to be coupled to a
lead connector, and an electrode member secured to the
underside of said lead connector hook, said viscous base
member with said central opening being viscous hoth on the
front and rear sides so as to be held in close contact
with the skin and on the front side coupled to said lead
connector.
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Brief ~escription of the Drawinqs
Fig. 1 is a perspective view showing the front side
of an embodiment of an electrocardiographic electrode
according to the invention;
Fig. 2 is a perspective view showing the rear or
back side of the electrocardiographic electrode;
Fig. 3 is a view for explaining the use of the
electrocardiographic electrode; and
Figs. 4 to 6 are views for explaining a prior art
electrocardiographic electrode.
A prior art electrocardiographic electrode which is
held in close contact with a person's skin in use will now
be described with reference to Figs. 4 to 6. Fig. 4 is a
perspective view of electrocardiographic electrode 1. The
electrocardiographic electrode has a substantially
circular, viscous base member 2. The viscous base member
2 is an annular woven cloth member having a central
aperture or opening 3. Its rear side, which is held in
close contact with the person's skin M as shown in Fig. 6,
is viscous, (i.e. sticky). The opening 3 of the viscous
base member 2 is closed by an ele!ctrode support 4, which
is made of a hard synthetic resin and is formed on the top
or front side of the viscous base member 2. A magnetic
lead coupler 5 projects from the front surface of the
electrode support 4. An electrode member 6 is secured to
the lower or rear surface of the lead coupler 5. The
electrode member 6 is held in direct contact with the
person's skin M to derive a weak voltage ~rom the person's
heart.
Fig. 5 shows the rear side of the lead coupler 7.
A lead 10 is coupled to the lead coupler 7 for feeding the
heart's weak voltage derived by the electrode member 6
through the lead 10 to the electrocardiograph (not
shown). The lead coupler 7 has substantially the same
size as the electrocardiographic electrode and is made of
a hard resin. It has a recess 8 formed on the rear side.
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A magnetic electrode coupler 9 is accommodated in the
recess 8 and secured to the bottom thereof. One end of
the lead 10 is connected to the electrode coupler 9, and
its other end is connected to the electrocardiograph (not
shown~.
To obtain an electrocardiogram using the
electrocardiographic electrode 1 having the above
con~truction, the viscous base member 2 o~ the electrode 1
is bonded to a person~s skin M, as shown in Fig. 6. Then,
the lead coupler 7 is coupled to the electrocardiographic
electrode 1 with its magnetic electrode coupler 9
magnetically attracted to the lead coupler S o the
electrocardiographic electrode 1. In this state, a
heart's weak voltage derived by the electrode member 6 is
coupled through the lead 10 to an electrocardiograph ~not
shown) for recording.
While the electrocardiographic electrode 1 is held
in close contact with the patient's skin for obtaining a
patient's electrocardiogram, the lead coupler 7 coupled to
the electrode 1 is liable to be detached from the
electrode due to an unconscious movement, e.g., due to the
patient tossing-about in sleep. In such a case, noise is
produced so that an accurate electrocardiogram can no
longer be obtained.
Further, the patient sometimes unconsciously pulls
out the lead 10 e~tending from the lead connector 7. If
the lead 10 is pulled extremely strongly, again detachmen-t
of the lead coupler 7 from the electrocardiographic
electrode 1 results, so that an accurate electrocardiogram
can no longer be obtained.
Further, the patient may take a bath with
electrocardiographic electrodes held in close contact with
the skin. Also, an electrocardiogram is sometimes
produced while the patient is taking part in physical
exercise, e.g., swimming. In such a caæe, a water-proof
suction member is used to cover the electrocardiographic
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electrode together with the lead connector. However, the
water-proof suction member is liable to be detached by the
action of water so that an accurate electrocardiogram can
no longer be obtained.
Detailed Description of the Preferred_Embodiment
An embodiment of the invention will now be
described with reference to the accompanying drawings.
Fig. 1 is a perspective view showing the front side of an
embodiment of an electrocardiographic electrode according
to the invention, and Fig. 2 is a perspective view showing
the rear side of the electrocardiographic electrode of
Fig. 1. The electrocardiographic electrode is designated
as 11.
The electrocardiographic electrode 11 has a viscous
base member 12. The viscous base member 12 is an annular
member having a central aperture or opening 13. The
detailed structure of the viscous base member 12 will be
described later.
The central opening 13 of the viscous base member
12 is closed by a disk-like reinforcement member 14 which
is bonded to the top or front surEace of the viscous base
member 12. As shown in FigO 1, the reinforcement member
14 has a smaller diameter than the viscous base member 12
and is made of vinyl chloride.
A lead connector hook 15 is made of metal and
penetrates the center of the reinforcement member 14. The
lead connector hook 15 has a lead coupler l5a projecting
from its top. A flat electrode member 16 made of Ag-AgCl
is connected to the bottom of the lead connector hook 15,
as shown in Fig. 2. A lead connector 17 with a lead 18 J
as shown in Fig. 3, is coupled to the projecting lead
coupler 15a. The other end of the lead 18 is connected to
an electrocardiograph (not shown).
An electrode member cover 19, as shown in Fig. 2,
is bonded to the electrode member 16. The cover 19
consists of a water-containing gel layer prepared from
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glutine, agar, polyacrylamide, etc. It has considerable
viscosity and al50 has electric conductivity.
The electrode member cover 19 is held in close
contact with the skin to feed a weak voltage induced on
the skin to the electrode member 16. Without the
electrode member cover 19, i.e., if the electrode member
16 is held in direct base contact with the skin, the weak
voltage can not be accurately measured due to the contact
resistance offered by the skin surface. Heretoore, it
has been the practice to apply beforehand cream or the
like to the skin to reduce the contact resistance, and the
electrode member 16 is held in contact with the cream for
the measurement of the weak voltage. To apply cream
whenever measurement of the weak voltage is done, however,
is cumbersome and inefficient. The water-containing gel
layer noted above, bonded to the electrode member 16,
performs a similar role to the cream and eliminates the
inconvenience of applying cream each time measurement is
made. The water-containing gel layer acting as the
electrode member cover 19 may be replaced with
polyurethane foam layer impregnated with jelly.
The viscous bass member 12, as shown in Figs~ 1 and
2r is disk-like and made by using foamed polyurethane, an
independently foamed butadiene rubber sheet non-woven
cloth and a woven cloth. The viscous base member 12
manufactured using the independently foamed butadiene
sheet has excellent cushioning properties and a light soft
touch, so that the electrocardiographic electrode can be
conveniently held in close contact with a person's skin.
As shown in Fig. ~, the rear surface 12b of the
viscous base member 12 is made viscous in order to obtain
close contact of the electrocardiographic electrode 11
with the person's skin M as shown in Fig. 3~ Further, the
viscous base member 12 is viscous not only on the rear
side 12b but also on the front side 12a, as shown in
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Fig. 1, so that a water-proof suction member ZO as shown
in Fig. 3 can be bonded to it.
The lead connector 17 is made of a metal, and it
has an engagement hole 17a formed substantially in its
central portion. The lead coupler 15a of the lead
connector hook 15 of the electrocardiographic electrode 11
is coupled to the engagement hole 17a.
The electrocardiographic electrode 11 having the
above construction is used as follows. First, the rear
surface 12b of the viscous base member 12 of the
electrocardiographic electrode 11 is held in close contact
with a person's skin M, as shown in Fig. 3. Then, the
lead connector 17 is coupled to the electrocardiographic
electrode 11 by fitting its engagement hole 17a on the
lead connector 15a of the lead connector hook 15 of the
electrocardiographic electrode 11 in close contact with
the person's skin M. Thereafter, the water-proof suction
member 20 is fitted to cover the lead connector 17 and
electrocardiographic electrode 11 coupled together. At
this time, the inner surface 20a of the water-proof
suction member 20 is held in close contact with the front
surface 12a of the viscous base member 12. Since the
front surface 12a of the viscous base member 12 is
viscous, the inner surface 20a of the water-proof suction
member 20 is bonded to the surface 12a. Thus, the
water-proof suction member 20 is firmly bonded to and
never detached from the electrocardiographic electrode 11.
As has been described in the foregoing, according
to the described embodiment, the viscous base member is
made viscous on both the font and rear sides, so that the
water-proof suction member can be held firmly bonded to
and never detached from the electrocardiographic
electrode. It is thus possible to obtain an
electrocardiograph of a patient while the patient is
taking a bath or exercising.
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Further, the e~fect of preventing the detachment of
the water-proof suction member from the
electrocardiographic electrode can be obtained very simply
and inexpensively by merely making both the front and back
surfaces of the viscous base member viscous.
