Inductor devices – Winding with terminals – taps – or coil conductor end...
Reexamination Certificate
2001-05-01
2003-01-07
Mai, Anh (Department: 2832)
Inductor devices
Winding with terminals, taps, or coil conductor end...
C336S208000, C361S035000
Reexamination Certificate
active
06504465
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an electromagnetic coil assembly for use in an electromagnetic apparatus, such as an electromagnetic clutch for use in controlling the transmission of power from an automobile engine to a refrigerant compressor in an automobile air conditioning system. More particularly, it relates to the structure for a securing member, which secures a thermal protection device in the electromagnetic coil assembly.
2. Description of Related Art
Referring to
FIGS. 1 and 2
, an electromagnetic coil assembly
4
, which comprises a bobbin
1
and a coil
3
, is known in the art. Bobbin
1
has a toroidal shape having a spool portion, which has an exterior open edge. Coil
3
is formed of an electrical wire
2
, which is wound around the spool portion. An electromagnetic coil assembly
4
, for example, is used in an electromagnetic clutch
6
of a compressor
5
in an automobile air conditioning system, as shown in FIG.
3
. Electromagnetic coil assembly
4
may be provided with a thermal protection device
7
, eg., a thermal fuse or a thermal switch, which is sensitive to high temperatures in electromagnetic clutch
6
. Thermal protection device
7
isolates a power source, such as an automobile engine, to protect electromagnetic clutch
6
and compressor
5
when high temperatures due to friction between the parts in electromagnetic clutch
6
are generated.
Referring again to
FIGS. 1 and 2
, in electromagnetic coil assembly
4
, thermal protection device
7
has a pair of leads, a first lead
7
a
and a second lead
7
b
, extending from either end of thermal protection device
7
. An end of first lead
7
a
of thermal protection device
7
is connected to a wire end portion
2
a
of electrical wire
2
through a first caulking terminal
8
. An end of second lead
7
b
of thermal protection device
7
is connected to a third lead
9
, which is connected to the external power source (not shown), through a second caulking terminal
10
. Thermal protection device
7
, first lead
7
a
and second lead
7
b
, wire end portion
2
a
, and a beginning portion of third lead
9
are disposed on a first end surface
1
a
of bobbin
1
. A pair of projection portions, a first projection portion
12
a
and a second projection portion
12
b
, are formed on first end surface
1
a
. Moreover, a securing member
11
having a groove-shaped cross-section, which is integrally molded with bobbin
1
, is disposed on a first end surface la of bobbin
1
. Securing member
11
extends on first end surface
1
a
and crosses at a right angle to the radial axis of the spool portion of bobbin
1
. An open edge of a groove of securing member
11
formed opposite to first end surface
1
a.
When thermal protection device
7
, first caulking terminal
8
, and second caulking terminal
10
are disposed on first end surface
1
a of bobbin
1
; a wire portion, which consists of wire end portion
2
a
of electrical wire
2
through beginning portion of third lead
9
, is drawn along the circumference of first end surface
1
a
. First lead
7
a
of thermal protection device
7
is secured by first projection portion
12
a
from the exterior open edge of bobbin
1
. Thereafter, thermal protection device
7
is inserted into the groove of securing member
11
, and second lead
7
b
of thermal protection device
7
is secured by second projection portion
12
b
from the exterior open edge of bobbin
1
. Thus, thermal protection device
7
, first caulking terminal
8
, and second caulking terminal
10
are secured on first end surface
1
a
of bobbin
1
.
As shown in
FIG. 4
, in electromagnetic coil assembly
4
, the groove of securing member
11
is formed of a first side wall
11
a
, which is positioned radially outward on first end surface
1
a
, and a second side wall
11
b
, which is positioned radially inward on first end surface
1
a
. A height of first side wall
11
a
is the same as a height of second side wall
11
b
. Therefore, thermal protection device
7
is inserted into the groove of securing member
11
from a direction perpendicular to the groove, as shown in the arrow of FIG.
4
.
With respect to securing thermal protection device
7
, the insertion of thermal protection device
7
into the groove of securing member
11
from the perpendicular direction may not be done in a series of steps, which consist of drawing the wire portion along the circumference of first end surface
1
a
, and securing first lead
7
a
and second lead
7
b
by projection portion
12
a
and projection portion
12
b
. When thermal protection device
7
is inserted into securing member
11
from a direction above and perpendicular to the groove of securing member
11
, the steps of drawing the wire portion along the circumference of first end surface
1
a
may be interrupted. As a result, the efficiency of the process of securing thermal protection device
7
, first caulking terminal
8
, and a second caulking terminal
10
on first end surface of bobbin
1
may be reduced.
SUMMARY OF THE INVENTION
A need has arisen to provide an electromagnet assembly for use in an electromagnetic apparatus which has an improved efficiency in fixing a thermal protection device and caulking terminals to an end surface of a coil bobbin, when compared with a known electromagnet assembly.
In an embodiment of the present invention, an electromagnetic coil assembly for an electromagnetic apparatus comprises a bobbin, a coil, and a thermal protection device. The bobbin comprises a cylindrical tubular spool, and a pair of annular flanges projecting radially from the spool to form an exterior open edge. The coil is formed of an electrical wire. The electrical wire is wound around the spool between the flanges. The thermal protection device has a first and a second lead wire, each extending from one side thereof. The first lead wire is connected to one end of the electrical wire through a first connecting member. The second lead wire is connected to one end of a third lead wire of an electrical circuit through a second connecting member. The thermal protection device, the first lead wire, the second lead wire, the first connecting member, the second connecting member, one end of the electrical wire, and one end of the third lead wire are disposed on a first end surface of the bobbin. A securing member having a groove-shaped cross-section is securely disposed on the first end surface of the bobbin. The securing member extends on the first end surface and crosses at a right angle to a radial axis of the spool, such that the thermal protection device is inserted into a groove of the securing member. A height of a fist side wall of the securing member, which is positioned radially outward on the first end surface, is lower than a height of a second side wall of the securing member, which is radially inward on the first end surface.
Other objects, features, and advantages will be apparent to persons of ordinary skill in the art from the following description of the invention with reference to the accompanying drawings.
REFERENCES:
patent: 3585450 (1971-06-01), Lane
patent: 4132913 (1979-01-01), Lautner et al.
patent: 4181393 (1980-01-01), Lill
patent: 4404534 (1983-09-01), Janvrin
patent: 4419536 (1983-12-01), Doyle et al.
patent: 4429358 (1984-01-01), Miyagi
patent: 4432446 (1984-02-01), Okano et al.
patent: 4557544 (1985-12-01), Esser
patent: 4623754 (1986-11-01), Kikuchi et al.
patent: 4935713 (1990-06-01), Bekheet
patent: 5121093 (1992-06-01), Matsushita
patent: 5138293 (1992-08-01), Ishimaru
patent: 5225801 (1993-07-01), Ida et al.
patent: 5307038 (1994-04-01), Ishimaru
patent: 5320206 (1994-06-01), Maejima
patent: 5483405 (1996-01-01), Kaelin
patent: 5508671 (1996-04-01), Takashi
patent: 5689182 (1997-11-01), Togo et al.
patent: 5889455 (1999-03-01), Sakamoto
patent: 6053448 (2000-04-01), Sakamoto
patent: 6069547 (2000-05-01), Sakamoto
patent: 6091590 (2000-07-01), Sakamoto
patent: 2248969 (1992-04-01), None
patent: 56138529 (1981-10-01), None
patent: 2106007 (1990-04-01), None
Baker & Botts L.L.P.
Mai Anh
Sanden Corporation
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