Title of Invention

ELECTROMAGNETIC SWITCH AND ELECTRIC COMPONENT

Abstract An electromagnetic switch conducting on-off operation by an electromagnetic solenoid under the effect of a return spring, in which an end plate is coupled magnetically to a yoke main body made of a magnetic material engaged to an electromagnetic solenoid, a yoke main body 19 clamped to a terminal holder, a movable core is in contiguous with a movable contact, a fixed core opposed to a movable core at an axially intermediate portion of a central hole in the bobbin is abutted against and positioned and fixed to the end wall of the yoke main body, and a return spring is interposed between the fixed core and the movable core so as to urge and position the movable core 38 to the terminal holder upon deenergization, whereby the movable core size can be decreased to save electric power consumption, and the size control is facilitated.
Full Text FORM 2
THE PATENT ACT 1970 (39 of 1970)
&
The Patents Rules, 2 003 COMPLETE SPECIFICATION
(See Section 10, and rule 13)
1. TITLE OF INVENTION
ELECTROMAGNETIC SWITCH AND ELECTRIC COMPONENT
2. APPLICANT(S)
a) Name : HONDA LOCK MFG. CO., LTD.
b) Nationality : JAPANESE Company
c) Address : 3,700, AZA-WADAYAMA,
SHIMONAKA, SADOWARA-CHO, MIYAZAKI-SHI, MIYAZAKI JAPAN
3. PREAMBLE TO THE DESCRIPTION
The following specification particularly describes the invention and the manner in which it is to be performed : -

SPECIFICATION
Electromagnetic Switch and Electric Component
BACKGROUND OF THE INVENTION
The present invention generally concerns an electromagnetic switch of moving a movable contact so as to be in
contact with and detached from fixed contacts by turning on or off a current to a coil thereby connecting or
disconnecting electrical conduction between a pair of fixed contacts.
The present invention further concerns an electromagnetic switch including an electromagnetic solenoid having
coils wound around a bobbin having a central hole and generating an electromagnetic force upon energization
for electrically conducting a movable contact to a pair of fixed contacts, and a return spring for exerting a spring
force for detaching the movable contact from the fixed contacts upon deenergization of the electromagnetic
solenoid.
the present invention further concerns an electric component in which a cap member is fitted to an open surface
of a case containing an electric part, and a liquid sealing material is cast to the upper surface of the cap member
to seal the engaging portion between the case and the cap member.
STATEMENT OF RELATED ART
An electromagnetic switch in which a plunger is inserted in a central hole provided in an electromagnetic solenoid
substantially over the entire axial length thereof and a plunger is drawn into the electromagnetic solenoid against
the spring force of a return spring upon energization thereby electrically conducting a movable contact with fixed
contacts has been.known, for example, in Japanese Utility Model Publication No. 27550/1989 (Patent Document
1).
For turning on and off a current circuit by a remote operation, an electromagnetic switch is adapted to move a
movable contact so that it can be in contact with or recede from the fixed contacts under the effect of an
electromagnet.
As an electromagnetic switch of this type, an electromagnetic actuator having an electromagnet and an armature
and tightly sealed in a case has been described in Patent Document 1.
As another example of the electromagnetic switch of this type, a plate terminal member integral with fixed
contacts is press-fitted into a slit formed in the base of a receptacle for connection with a plug of a wire harness
has been known, for example, in Japanese Patent Laid Open No. 349395/1994 (Patent Document 2)..
By the way, for the device disclosed in the Patent Document 1, it is necessary to draw the plunger by a strong
electromagnetic force exceeding the weight of the plunger itself and, in addition, overcoming the spring force of
the return spring depending on the attaching position of the electromagnetic switch. This increases consumption
power of the electromagnetic solenoid by so much and results in enlargement of the entire size scale of the
electromagnetic switch.
Then, it may be considered to make a movable contact in contiguous with a movable core that opposes fixed
contacts to thereby decrease the size of the movable core and reduce the electromagnetic force to be generated
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by the electromagnetic solenoid smaller. However, a dimensional control between the movable core and the
fixed core is important in this case.
SUMMARY OF THE INVENTION
The present invention has been achieved in view of the foregoing situation and it is an object thereof to provide
an electromagnetic switch capable of decreasing the size of a movable core which is in contiguous with a
movable contact and opposed to a fixed core thereby setting the electromagnetic force to be generated by the
electromagnetic solenoid smaller, and facilitating the dimensional control between the fixed core and the
movable core.
According to the existent structure described in the Patent Document 2. while the terminal plate is prevented
from slipping out of the base by the connection of a check pawl disposed on a base portion thereof to an opening
of the slit, the connection portion of the terminal plate to the slit may sometimes be slackened during repetitive
attachment and detachment of the plug.
The present invention has been achieved in order to overcome the disadvantage in the prior art described above
and a principal object thereof is to provide an electromagnetic switch improved such that the connection portion
of a terminal plate to a slit formed in a base is not slackened.
According to the existent structure described in the Patent Document 1, an O-ring has to be attached to an
engaging portion between a case and the cover for engaging a cover having fixed contacts secured thereon to
an open surface of the case and sealing the electromagnetic actuator in the case.
Accordingly, an attaching portion for the O-ring has to be formed to the case or the cover and, in addition, it takes
additional labors for mounting the O-ring.
While it has a|so been well-known to seal a case by casting a heat setting resin material such as an epoxy type
resin to an engaging portion between the case and the cover, the resin material has to be cast in a somewhat
excessive amount in this method in order that it prevails sufficiently to the portion to be sealed. Accordingly, it
needs a surplus material cost and also takes a long curing time. That is, any of the methods described above
was not satisfactory in view of economicity and productivity.
The present invention has been achieved also for solving such disadvantages in the prior art and an object
thereof is to provide an electric component in which an engaging portion between a case and a cap member is
sealed by a sealing method which is economical and of high productivity.
For attaining the foregoing object, the invention according to a first aspect provides an electromagnetic switch
including; an electromagnetic solenoid having coils wound around a bobbin having a central hole and generating
an electromagnetic force for electrically conducting a movable contact with a pair of fixed contacts upon
energization, and
a return spring for exerting a spring force of detaching the movable contact from the fixed contact upon
deenergization of the electromagnetic solenoid, in which an end plate made of a magnetic material opposed to
the other end of the bobbin is magnetically connected to a yoke main body made of a magnetic material, which
has an end wall at one end opposed to one end of the bobbin and engages the electromagnetic solenoid, so as
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to constitute a yoke together with the yoke main body, the other and of the yoke main body which is clamped and
fixed to a terminal holder made of a non- magnetic material having, being passed therethrough, a pair of coil
contact terminals connected with both ends of the coil and a pair of contact connection terminals integrally having
the fixed contacts, and sandwiching the end plate relative to the other end of the bobbin,
a movable core is in contiguous with the movable contact which can be in contact with or detached from both of
the fixed contacts, a fixed core which is at least partially inserted in the central hole and opposed to the movable
core in the intermediate axial direction of the central hole is abutted against the end wall of the yoke main body
and positioned and fixed, and a return spring is interposed between the fixed core and the movable core so as to
provide a spring force of pressing and positioning the movable core to the side of the terminal holder upon
deenergization of the electromagnetic solenoid.
According to the second aspect of the invention as described in the first aspect of the invention, the fixed core
integrally has a bar-shaped portion inserted in the central hole and opposed to the movable core, and a flange
portion extending outward in the radial direction from one end of the bar-shaped portion and sandwiched
between the end wall of the yoke main body and one end of the bobbin.
According to the third aspect of the invention as described in the second aspect of the invention, the yoke main
body is clamped and fixed to the terminal holder so as to exert a force pressing to the side of the end wall of the
yoke main body from the terminal holder to the end plate and the bobbin.
According to the fourth aspect of the invention as described in any one of first to third aspects of the invention in
any one of firs.t to third aspect, bottomed receiving holes are coaxially disposed at the opposing surfaces of the
movable core and the fixed core, respectively, and both ends of the coiled return spring partially received in the
receiving holes are abutted against the closed ends of both of the receiving holes.
According to the fifth aspect of the invention as described in any one of the first to fourth aspects, the
electromagnetic solenoid, the yoke, the fixed core, the movable core, and the return spring are contained in a
bottomed cylindrical case, the terminal holder that closes the open end of the case is engaged and fixed to the
case so as to form a concave portion facing outward in co-operation with the case, and a potting agent is filled in
the concave portion so as to bury a gap between the outer circumference of the terminal holder, and the case,
and a gap between each of the terminal holder, and the both of the coil connection terminals and both of the
contact connection terminals.
In another aspect, the invention provides an electromagnetic switch including a terminal base or holder made of
an insulative material, a terminal plate inserted to a slit formed in the terminal base or holder from the inside of
the terminal base, and an electromagnet (bobbin and coil) at a position facing the inner surface of the terminal
base, in which protrusions abutting against the base end of the terminal plate (fixed contact) are disposed to the
bobbin of the electromagnet at the surface facing the inner surface of the terminal base.
In a further aspect, the invention provides an electric component, for example, an electromagnetic relay in which
a cap member (terminal base) having terminals secured thereon is engaged to an open surface of a case for
containing an electric part such as an electromagnetic actuator, and a liquid sealing material (epoxy resin
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material) to the upper surface of the cap member to seal an engaging portion between the case and the cap
member, wherein an inclined surface which is made higher at a central portion and lowered toward the outside is
formed to the upper surface of the cap member surface. The liquid sealing material is cast particularly preferably
to the vicinity of the highest portion of the inclined surface.
According to the first aspect of the invention, since the fixed core and the movable cores are opposed in the
axially intermediate portion of the central hole formed in the bobbin of the electromagnetic solenoid, the size of
the movable core can be decreased. Accordingly, it is possible to set the electromagnetic force to be generated
from the electromagnetic solenoid smaller, to thereby decrease the electric power consumption of the
electromagnetic solenoid and decrease the entire size of the electromagnetic switch. Further, since the fixed core
is positioned and fixed being abutted against the end wall of the yoke main body and the movable core having
the return spring interposed with respect to the fixed core is urged to the terminal holder for sandwiching the end
plate constituting the yoke together with the yoke main body and the electromagnetic solenoid with respect to the
end wall by the return spring upon deenergization of the electromagnetic solenoid, the size control between the
fixed core and the movable core can be conducted easily by controlling the size between the end wall of the yoke
main body and the terminal holder.
Further, according to the second feature of the invention, the fixed core can be positioned and fixed stably by
sandwiching the flange portion provided to the fixed core between the end wall of the yoke main body and one
end of the bobbin, and this is advantageous in view of the magnetic circuit by enlarging the area of contact of the
yoke main body and fixed core.
According to the third aspect of the invention, since the yoke main body is clamped and fixed to the terminal
holder so as to exert a force of urging pressing to the side of the end wall of the yoke main body from the
terminal holder to the end plate and the bobbin, the positional accuracy for the bobbin, that is, for the coil is
improved.
According to the fourth aspect of the invention, since both ends of the coiled return spring partially received
respectively in the bottomed receiving holes disposed respectively to the movable core and the fixed core are
abutted against the closed end of both of the receiving holes, the adsorption area of the fixed core for adsorbing
the movable core can be set greatly while enabling the return spring to exert a sufficient spring load compared
with a case in which the return spring is interposed between the outer peripheral portions of the fixed core and
the movable core.
Further, according to the fifth aspect of the invention, water proofness in the case can be improved while
containing the electromagnetic solenoid, the yoke, the fixed core, the movable core, and the return spring in the
case.
According to the sixth aspect of the invention, since a force exerting on the terminal plate, for example,, upon
attaching the plug is received by the protrusions disposed to the bobbin, immersion and deformation of the
terminal plate can be prevented without complicating the anti-slip off shape of the terminal plate with no particular
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addition of another part. Accordingly, it can provide a great effect in view of improving the durability for repetitive
attachment and detachment without complicating the structure of the electromagnetic switch of this type.
According to the seventh to ninth aspects of the invention, since the liquid sealing material flows along the
inclined surface to a portion of the outer periphery that requires sealing, a minimum necessary amount of the
sealing material can be cast only to the portion to be sealed with no loss. Accordingly, this can provide a great
effect in view of improving both the economicity and the productivity in the manufacture of an electric component
such as an electromagnetic relay.
BRIEF DESCRIPTION OF THE DRAWINGS
Now, preferred embodiments of the invention are to be described by way of embodiments of the present
invention with reference to the appended drawings.
Fig. 1 is a vertical cross sectional view of an electromagnetic switch according to the first aspect of the invention;
Fig. 2 is a cross sectional view along line 2-2 in Fig 1;
Fig. 3 is an exploded perspective view of an electromagnetic switch with coils being omitted;
Fig. 4 is a cross sectional view along line 4-4 of Fig. 1;
Fig. 5 is an entire perspective view of an electromagnetic switch;
Fig. 6 is a perspective view for the appearance of a device according to another aspect of the invention in an
assembled state;
Fig. 7 is an upper plan view thereof;
Fig. 8 is a cross sectional view along line Ill-Ill in Fig. 7;
Fig. 9 is a cross sectional view along line IV-IV in Fig. 7; and
Fig. 10 is an enlarged view for the pointed top end of a protrusion used in the invention.
PREFERRED EMBODIMENTS OF THE INVENTION
At first, in Fig. 1 and Fig. 2, an electromagnetic switch according to the first aspect of the invention has a
magnetic solenoid 13 that generates an electromagnetic force for electrically conducting a movable contact 12
with a pair of fixed contacts 26a, 26a during current supply (upon energization), and a return spring 14 for
exerting a spring force for detaching the movable contact 12 from the fixed contacts 26a, upon deenergization of
the electromagnetic solenoid 13, which is used, for example, for a vehicle starter circuit.
Also referring to Fig. 3. the electromagnetic solenoid 13 is formed by winding coils 17 around a bobbin 16 made
of a synthetic resin having a central hole 15. The bobbin 16 integrally has a cylindrical portion 16a defining the
central hole 15, a circular first flange 16b outwardly extending in the radial direction from one end of the
cylindrical portion 16a, and a square second flange 16c outwardly extending in the radial direction of the
cylindrical portion 16a near the other end thereof such that the other end of the cylindrical portion 16a is slightly
protruded. Coils 17 are wound around the cylindrical portion 16a between the first and the second flanges 16b,
16c.
The electromagnetic solenoid 13 is surrounded with a yoke 18, and the yoke 18 has a yoke main body 19 made
of a magnetic material and engaged to the electromagnetic solenoid 13 and an end plate 20 made of a magnetic
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material and magnetically coupled to the yoke main body 19. The yoke main body 19 integrally has first and second side walls 19a, 19b for sandwiching the bobbin 16 on both sides thereof and an end wall 19c that connects respective one ends of the first and the second side walls 19a, 19b, opposes to one end of the bobbin 16, that is, the first flange 16b, and is formed substantially into a U-shaped configuration. Further, clamping arms 19d, 19d extending on both sides are integrally protruded so as to be bendable to the other end of the first side wall 19a, and a clamping portion 19a that can be bent inward is integrally protruded at the central portion on the other end of the second side wall 19b so as to form a rectangular opening 21 relative to the other end of the second side wall 19.
Further, the end plate 20 is located so as to sandwich the bobbin 16 relative to the end wall 19c and formed into a plate shape, and has an insertion hole 22 being formed for inserting a protrusion therethrough from the second flange 16c of the cylindrical portion 16a in the bobbin 16, and abutted against the second flange 16c of the bobbin 16. Further, the end plate 20 has a pair of first positioning holes 23, 23 for engaging a pair of first positioning pips 16d, 16d protruded to the second flange 16c of the bobbin 16 and a pair of second positioning holes 24, 24, each of a diameter smaller than the first positioning pin 16d, -- for engaging a pair of second positioning pins 16e, 16e protruded to the second flange 16c of the bobbin 16, respectively. Then, in a state of positioning the end plate 20 to the yoke main body 19 by engaging the first positioning pins 16d. -- to the first positioning holes 23, — and engaging the second positioning pins 16e, — to the second positioning holes 24, the end plate 20 is in contact with the inner surface on the other end of both of the side walls 19a, 19b provided to the yoke main body 19 engaged to the electromagnetic solenoid 13, by which the yoke main body 19 and the end plate 20 are coupled magnetically.
Further, a pair of engaging and holding portions 16f, 16f for engaging and holding engaging protrusions 27a, 27a disposed integrally to a pair of coil connection terminals 27, 27, respectively, to both ends of the coils 17 wound around the bobbin 16 respectively are protruded to the second flange 16c of the bobbin 16. Recesses 28 and 28 are formed to the end plate 20 on both sides of the second positioning holes 24 for arranging the fitting and holding portions 16f.
Also with reference to Fig. 4, the other end of the yoke main body 19, that is, each other end of both side walls 19a and 19b is clamped to a terminal holder 29 made of a non- magnetic material, for example, a synthetic resin for sandwiching the end plate 20 with respect to the other end of the bobbin 16. The terminal holder 29 integrally has a holder main portion 29a formed into a rectangular shape with its longitudinal direction being aligned with the direction of arranging both side walls 19a and 19b of the yoke main body 19, and a connection protrusion 29b having first and second abutting surfaces 30 and 31 that abut against the inner surface on the other end of both side walls 19a and 19b of the yoke main body 19 respectively.
The connection protrusion 29b has engaging concave portions 32 and 32 formed on both sides of the first abutting surface 30 for clamping and engaging the engaging arms 19d, - - protruded on both sides at the other end of the first side wall 19a in the yoke main body 19 respectively such that they are bent each at a right angle. Further, the connection protrusion 29b has an engaging concave portion 33 such that it is opened in the central
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portion of a second abutting surface 31 for engaging the clamping portion 19e protruded at the central portion of the other end of the second side wall 19b in a state it is bent inward. Further, a plurality of protrusions 34, —, for example, by the number of three are protruded to the connection portion 29b so as to abut against the end plate 20oftheyoke18.
Then, the terminal holder 29 is clamped and fixed to the other end of the yoke main body 19 by clamping and engaging the clamping arms 19b, — to the engaging concave portions 32, — and by clamping and engaging the calking portion 19e to the engaging concave portion 33. By clamping and fixing the protrusions 34, — are pressed against the end plate 20 while being crushed partially. That is, the yoke main body 19 is caulked and clamped to the terminal holder 29 so as to exert a pressing force to the side of the end wall 19e of the yoke main body 19 from the terminal holder 29 to the end plate 20 and the bobbin 16.
In the connection protrusion 29b of the terminal holder 29, a pair of fixed contacts 26a, 26a having arcuate connection portions 26b raised on the side opposite to the end plate 20 and set in parallel are positioned and arranged with a predetermined distance between each other, and the fixed contacts 26a, 26a are disposed integrally to the contact connection terminals 26, 26 passing through the terminal holder 29. Further, in a state where the terminal holder 29 is clamped and fixed to the other end of the yoke main body 19, top ends of the first and the second positioning pins 16d, — and 16e. — protruded each in pair from the second flange 16c of the bobbin 16 abut against both of the fixed contacts 26a, 26a, by which both of the fixed contacts 26a, 26a are positioned and fixed to the connection protrusion 29b.
Further, a pair of coil connection terminals 27, 27 passing through the terminal holder 29 integrally have positioning portions 27b, 27b which are abutted against and positioned at the connection protrusions 29b, and engaging protrusions 27a, — engaged and held to the engaging and holding portions 16f, — provided to the
second flange 16c of the bobbin 16 are protruded from the positioning portions 27b,
In the holder main portion 29a and the connection protrusion 29b, a receiving concave portion 35 opened to the end plate 20 is formed such that a portion of the open end is closed by both of the fixed contacts 26a, 26a, and the movable contact 12 that can be in contact with and recede from the connection portions 26b. 26b of both of the fixed contacts 26a, 26a is received in the receiving concave portion 35 such that it partially protrudes through a portion between both contacts 26a and 26a toward the electromagnetic solenoid 13. The movable contact 12 integrally has a bottomed cylindrical portion 12a that protrudes through a portion between the connection portions 26b, 26b of both of the fixed contacts 26a, 26b toward the electromagnetic solenoid 13, and a flange 12b that extends from the open end of the bottomed cylindrical portion 12a outward in the radial direction. When the flange 12b is in contact with the connection portions 26b, 26b of both of the fixed contacts 26a, 26a, both of the fixed contacts 26a, 26a are electrically conducted by way of the movable contact 12 and, when the flange 12b recedes from the connection portions 26b, 26b of both of the fixed contacts 26a, 26a, both of the fixed contacts 26a, 26a are electrically disconnected.
A guide protrusion 36 protruding from the central portion at the closed end of the receiving concave portion 35 is formed integrally in the holder main body 29a, and the guide protrusion 36 is inserted in the bottomed cylindrical
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portion 12a of the movable contact 12. A coiled spring 37 that surrounds the guide protrusion 36 is disposed under compression between the closed end of the bottomed cylindrical portion 12a and the closed end of the receiving concave portion 35, so that the movable contact 12 is resiliently biased by the spring 37, with the flange 12b thereof being directed to the side in contact with the connection portions 26b, 26b of both of the fixed contacts 26a, 26a. Further, the spring load of the spring 37 is set smaller compared with the spring load of the return spring 14.
The movable contact 12 is in contiguous with a movable core 38. The movable core 38 integrally has a bar-shaped movable core main body 38a one end of which is inserted in the central hole 15 in the electromagnetic solenoid 13 and a flange 38b that extends outwardly in the radial direction at the other end of the main body. The central portion at the other end of the movable core main portion 38a is coaxially abutted against the outer surface on the closed end of the bottomed cylindrical portion 12a formed in the movable contact 12, by which the movable core 38 is in contiguous with the movable contact 12.
A fixed core 39 at least partially inserted in the central hole 15 is opposed to the movable core 38 at the axially intermediate portion in the central hole 15, and the fixed core 39 is positioned and fixed being abutted against the end wall 19c of the yoke main body 19. That is, the fixed core 39 integrally has a bar-shaped portion 39a inserted in the central hole 15 and opposed to the movable core 38 and a flange 39b that extends outward in the radial direction from one end of the bar-shaped portion 39a. The flange 39b is put between the end wall 19c of the yoke main body 19 and one end of the bobbin 16.
Further, bottomed receiving holes 40, 41 are coaxially disposed respectively at the opposed surfaces of the movable core 38 and the fixed core 39, and both ends of the return spring 14 which is coiled in the shape and received partially in both of the receiving holes 40, 41 are abutted against the closed ends of both of the containing holes 40,41.
Then, upon energization of the electromagnetic solenoid 13, the movable core 38 is attracted to the fixed core 39 and the movable contact 12, which is resiliently biased by the spring 37 moves following after the movement of the movable core 38 as far as a position in contact with the connection portions 26b, 26b of both of the fixed contacts 26a, 26a. On the other hand, upon deenergization of the electromagnetic solenoid 13, the movable core 38 is moved by the spring force of the return spring 14 so as to press the movable contact 12 in the direction receding from both of the fixed contacts 26a, 26a against the spring force of the spring 37. A plurality of restriction protrusions 42, — that abut against the flange 12b of the movable contact 12 to restrict the movement of the movable contact 12 are protruded from the closed end of the receiving concave portion 35 so as to be arranged at the periphery of the guide protrusion 36. The movable core 38 is pressed and positioned to the restricting protrusions 42, -- of the terminal holder 29 by way of the movable contact 12 by the spring force of the return spring 14 upon deenergization of the electromagnetic solenoid 13.
Referring also to Fig. 5, the electromagnetic solenoid 13, the yoke 18, the fixed core 39, the movable core 38, and the return spring 14 are contained in a bottomed cylindrical case 44 having a substantially rectangular transverse cross sectional shape made of a non-magnetic material, for example, a synthetic resin.
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A portion of the case 44 on the side of the open end is formed as a large diameter cylindrical portion 44a having an outward-facing closed step 44b formed at the inner surface, and the holder main portion 29a of the terminal holder 29 engages the large diameter cylindrical portion 44a so as to abut against the step 44b. Further, engaging fingers 46, 46 integrally formed to the outer lateral surface of the holder main portion 29a resiliently engage engaging concave portions 45, 45 formed at two positions on the inner surface of the large diameter cylindrical portion 44a, and the terminal holder 29 that closes the open end of the case 44 is engaged and fixed to the case 44.
Further, the outer surface of the holder main portion 29a in the terminal holder 29 situates inward of the open end of the case 44 in the engaged state of the terminal holder 29 to the case 44, and the terminal holder 29 forms a concave portion 47 facing outward in co-operation with the case 44.
Further, a pair of coil connection terminals 27 -- and a pair of contact connection terminals 26 -- protrude outward from the holder main portion 29a of the terminal holder 29, and a pair of fixed wall portions 29c, 29c in parallel with each other and a pair of flexible wall portions 29d, 29d disposed between both ends of the fixed wall portions 29c, — are integrally protruded to the holder main portion 29a so as to surround both of the coil connection terminals 27, — and both of the contact connection terminals 26, —. Further, for resiliently distorting both of the flexible wall portions 29d, —, rectangular windows 48, -- are formed to the flexible wall portions 29d, -—. Then, both of the fixed wall portions 29c. — and both of the flexible wall portions 29d, — can fit and resiliently engage to an external connecter not illustrated, and both of the coil connection terminals 27, -- and both of the contact connection terminals 26, -- are connected to corresponding female terminals in the external connector respectively in a state connected with the external connector.
Then, upon connection with the female terminals of the external connector, both of the contact connection terminals 26, -- undergo a force of detaching the fixed contacts 26a integrally provided to the contact connection terminals 26 -- from the connection protrusion 29b of the terminal holder 29.
However, the top ends of the pair of the first positioning pins 16d, -- and the pair of the second pins 16e, --protruded at the second flange 16c of the bobbin 16 abut against the fixed contacts 26a, — on the side opposite to the terminal holder 29, detachment of the fixed contacts 26a, -- from the connection protrusion 29b can be prevented reliably.
Further, in the concave portion 47 formed with the terminal holder 29 and the case 44, a potting agent 49 such as an epoxy resin is filled so as to bury a gap between the outer circumference of the holder main portion 29a in the terminal holder 29 and the case 44, as well as a gap between the terminal holder 29 and both of the coil connection terminal 27 and both of the contact connection terminals 26, --.
In the holder main portion 29a, a raised portion 29e is formed to the central portion at the surface facing the side opposite to the case 44 so as to avoid lowering of the strength caused by the provision of the receiving concave portion 35, and the potting agent 49 is filled in the concave portion 47 except for the raised portion 29b. Further, the outer peripheral surface of the raised portion 29e is tapered and, when the potting agent 49 is dripped to the central area of the raised portion 29e with the raised portion 29e being upwarded, the potting agent 49 spreads
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so as to flow down on the outer peripheral surface of the raised portion 29e, so that the potting agent 49 fills the concave portion 47 except for the raised portion 29e.
Then, referring to the operation of this embodiment, since the movable core 38 is in contiguous with the movable contact 12 which can be in contact with or recede from a pair of the fixed contact 26a, 26a, and the fixed core 39 to be inserted at least partially in the central hole 15 of the bobbin 16 is opposed to the movable core 38 in the axially intermediate portion of the central hole 15, the size of the movable core 38 can be decreased. Thus, the electromagnetic force to be generated from the electromagnetic solenoid 13 can be set smaller, thereby capable of decreasing the power consumption by the electromagnetic solenoid 13 and decreasing the size of the entire electromagnetic switch.
Further, the end plate 20 opposing to the other end of the bobbin 16 is magnetically coupled, together with the yoke main body 19, to the yoke main body 19 which has, at one end thereof, the end wall 19c opposed to one end of the bobbin 16 and engages the electromagnetic solenoid 13 so as to constitute the yoke 18, the other end of the yoke main body 19 is clamped to the terminal holder 29 through which a pair of coil connection terminals 27, 27 in contiguous with both ends of the coil 17 and a pair of contact connection terminals 26,26 integrally having the fixed contacts 26a, — respectively are passed therethrough and which sandwiches the end plate 20 with respect to the other end of the bobbin 16, the fixed core 39 is abutted against and fixed and positioned at the end wall 19c of the yoke main body 19, and the return spring 14 is interposed between the fixed core 39 and the movable core 38 so as to exert a spring force of urging and positioning the movable core 38 to the terminal holder 29 by way of the movable contact 12 upon deenergization of the electromagnetic solenoid 13. Accordingly, the size control between the fixed core 39 and the movable core 38 can be conducted easily by conducting size control between the end wall 19c of the yoke main body 19 and the terminal holder 29. Further, since the fixed core integrally has the bar- shaped portion 39a inserted in the central hole 15 and opposed to the movable core 38 and a flange portion 39b extending outward in the radial direction from one end of the bar-shaped portion 39a and put between the end wall 19c of the yoke main body 19 and one end of the bobbin 16, the fixed core 39 can be stably positioned and fixed by sandwiching the flange portion 39b between the end wall 19c of the yoke main body 19 and one end of the bobbin 16, as well as the area of contact of the yoke main body 19 and the fixed core 39b can be increased to provide an advantage in view of the magnetic circuit.
Further, since, the yoke main body 19 is clamped and fixed to the terminal holder 29 so as to exert a pressing force toward the end wall 19c of the yoke main body exerts from the terminal holder 29 to the end plate 20 and the bobbin 16, the positional accuracy for the bobbin 16, that is, the coil 17 can be improved. Further, since the bottomed receiving holes 40, 41 are coaxially disposed at the opposed surfaces of the movable core 38 and the fixed core 39 respectively and both ends of the coiled return spring 14 partially received in the receiving holes 40, 41 respectively are abutted against the closed ends of both of the containing holes 40, 41, the adsorption area for of the fixed core 39 for magnetically adsorbing the movable core 38 can be set larger
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thereby enabling the return spring 14 to provide a sufficient spring load as compared with a case where the return spring 14 is interposed between the outer peripheries of the fixed core 38 and the movable core 38 Further, since the electromagnetic solenoid 13, the yoke 18, the fixed core 39, the movable core 38, and the return spring 14 are contained in the bottomed cylindrical case 44.
the terminal holder 29 for closing the open end of the case 44 is engaged and fixed to the case 44 so as to form a concave portion 47 facing outward in cooperation with the case 44, and the potting agent 49 fills the concave portion 47 so as to bury at least a gap between the outer periphery of the terminal holder 29 and the case 44, as well as a gap between the terminal holder 29 and both of the coil connection terminals 27, — and both of the contact terminals 26, —, the water proofness inside the case 44 can be improved while containing the magnetic solenoid 13, the yoke 18, the fixed core 39, the movable core 38, and the return spring 14 in the case 44. Then other aspects of the present invention are to be described specifically by way of another embodiment with reference to Fig. 6 to Fig. 10 of the appended drawings.
An electric component, specifically, an electromagnetic switch 1 according to the present invention includes, as shown in Fig. 6, an electromagnetic actuator section 102 and a connector section 103. The directionality to be described below is assumed to be directed to the surface of the drawing paper but this is only for the convenience of description and the directionality in actual use is not restricted thereto. As also shown in Fig. 7 to Fig. 9 together, the electromagnetic actuator section 102 is contained in a cuboidal case 104 made of an insulative material and opened at the upper surface, and includes a bobbin 105 and a coil 106 wound around bisected yokes 107a, 107b which are externally disposed to the coil 106, an armature 108 inserted in the central hole 105a of the bobbin 105 from the upper end of the bobbin 105, a core inserted into the central hole 105a of the bobbin 105 from the lower end of the bobbin 105, and a coiled compression spring 110 normally exerting a resilient force in the direction where the armature 108 and the core 109 recede from each other between the armature 108 and the core 109.
The bobbin 105 made of an insulative material has a flange 111 substantially of a square shape at an upper end thereof and a flange 112 substantially of a circular shape at the lower end thereof each formed integrally. Then, on the rear edge of the square flange 111, a pair of current supply terminal plates 113 each of an elongate plate shape extending vertically with the longitudinal direction thereof being along the axial line of the bobbin 105 are fixed by press-fitting the base ends thereof into backward-open horizontal holes formed in the rear edge portion of the square flange 111 although not illustrated. Respective ends of conductors constituting the coil are soldered to the base end of the current supply terminal plates 113.
The connector section 103 includes a receptacle 114 opened upward for receiving a plug (not illustrated) disposed to the terminal end of a wire harness and providing anti-slip off function, a terminal base 115 formed integrally with, the receptacle 114 on the lower end of the receptacle 114, switch terminal plates 117 having fixed contacts 116 formed integrally to the base end thereof secured to the terminal base 115, a movable contact plate 118 put between the lower surface of the terminal base 115 and the upper surface of the fixed contacts 116 vertically movably, and a coiled compression spring 119 always exerting a resilient force in the direction of
12

abutting the movable contact plate 118 and the fixed contact 116 to each other to a portion between the terminal base 115 and the movable contact plate 118. Then, by engaging the terminal base 115 to the open surface of the case 104, the constituent components of the electromagnetic actuator section 102 are sealed in the case 104. Two sets of slits 120,121 elongated in the forward-to- backward direction are formed to the terminal base 115 made of the insulative material for inserting therethrough the power supply terminal plates 113 and switch terminal plates 117 each of a shape similar with the current supply terminal plate 113 and formed slightly larger than the power supply terminal plate 113 respectively. A pair of switch terminal plates 117 are previously press fitted into one sets 121 of the slits described above while sandwiching the movable contact plate 118 with respect to the lower surface of the terminal base 115 Then, upon engaging the terminal base 115 having the switch terminal plates 117 assembled thereto to the open surface of the case 104, the current supply terminal plates 113 secured to the square flange 111 of the bobbin 105 passes through the slits and protrude to the inside of the receptacle 114 integrated with the terminal base 115.
The fixed contacts 116 formed at the base ends of the switch terminal plates 117 are bent each at a right angle from the switch terminal plates 117, elongated in the forward-to-backward direction, and extended at the rear end thereof to a portion between the base ends of a pair of the current supply terminal plates 113. Further, upward bent protrusions 122 are formed at the front end and the rear end of the fixed contacts 116, and the protrusions 122 are press-fitted into the holes 123 formed in the lower surface of the terminal base 115 thereby positioning the switch terminal plates 117 and providing anti-slip off function to them.
On the upper surface of the square flange 111 of the bobbin 105, two sets of protrusions 124,125 are protruded (at four positions) along the axial line of the bobbin 105. The protrusions 124,125 correspond to respective ends in the front-to-back direction of a pair of fixed contacts 116, and the top ends of the protrusions 125,125 abut against the respective ends in the front-to-back directions of respective fixed contacts 116 upon engaging the terminal base 101 having the switch terminal plates 117 assembled thereto to the open surface of the case 104. The top end of each of the protrusion 124,125 is pointed into a conical shape as shown in Fig. 10. When the pointed top end is urged to the fixed contacts 116, the pointed top end is crushed and the upper surface of the fixed contacts 116 is in press contact with the lower surface of the terminal base 115 by the reaction of deformation. This can provide reliable positioning and anti-rattling function with respect to the vertical direction of the switch terminal plate 117 even when production error or assembling error should be caused in each of the portions.
In a case where protrusions similar with the protrusions described above are arranged at least by the number of three each atan equal angle on the bottom face of the case 104 and adapted such that the protrusions abut against the yoke 107a upon assembling the terminal base 112 to the case 104, and the pointed top ends of the protrusions are crushed in the same manner as described above, rattling of the yoke 107a can be prevented. A raised convex portion 126 with the height being increased toward the center is formed at the central portion of the upper surface at the inside of the receptacle 114 of the terminal base 115 made of the insulative material. When an epoxy type resin material or the like is, cast from a nozzle N suspended toward the vicinity of the top
13

surface of the convex portion 126. with the convex portion 126 being upwarded, the epoxy type resin material
127 is caused to flow along the inclined surface C of the convex portion 126 to the lower portion of the inclined
surface C that is, to the outer periphery of the terminal base 115 and flows into an engaging portion between the
terminal base 115 and the case 104 to completely seal the engaging portion. Further, since the slits 120,121
through which the terminal plate 113, 117 are inserted respectively are formed at the lowest surface of the
terminal base 115, a gap between each of the terminal plates 113,117 and each of the slits 120,121 is also
closed by the epoxy type resin material 127.
As described above, by guiding the flow of the liquid sealing material to a predetermined direction along the
inclined surface C lowered to the outside, a portion to be sealed can be sealed reliably by a minimum amount
even in a case of using a sealing material of a relatively high viscosity. For the profile of the convex portion 126,
while a flat pyramidal shape or conical pyramidal shape may be considered, it may suffice so long as the inclined
surface C lowered to the outside is formed.
When a plug of a wire harness is connected to the receptacle 114 of the electromagnetic switch 101 assembled
as described above and a current is supplied from the current supply terminal plate 113 to the coil 106, the coil
106 is excited to generate a magnetic flux passing through the core 109 and the armature 108 by way of the
yoke 107. Then, the armature 108 is attracted to the core 109 against the resiliency of the coiled compression
spring 110, to eliminate the pressing force of detaching the movable contact plate 118 from the fixed contacts
116. Thus, the movable contact plate 118 moves together with the armature 108 by the resiliency of the coiled
compression spring 10 and abuts against a pair of the fixed contacts 116 to electrically contact both of the fixed
contacts 116 to each other.
Upon connecting the plug to the receptacle 114, while a downward force, that is, a force of enforcing the switch
terminal plates 117 in ward of the case 104 exerts on the switch terminal plates 117, since the fixed contacts 116
integrated with the switch terminal plates 117 abut against the protrusions 124, 125 protruded to the upper
surface of the bobbin 105 and the downwarding force exerting on the switch terminal plates 117 is received at
the protrusions 124,125, there is no worry that the switch terminal plates 117 are slackened.
The constitution of the electromagnetic switch as the preferred embodiment to the invention has an effect of
preventing the terminal plate from slackening and it is applicable equally also to an electromagnetic relay, etc. to
be inserted into the receptacle of a substrate.
The constitution of the electric component as the preferred embodiment according to the invention has an effect
of sealing a portion between the case and the cover, .which is applicable equally, for example, to an
electromagnetic relay or a transformer.
While the embodiments of the present invention have been described, the invention is not restricted to the
embodiments described above but various design changes are possible without departing the invention
described in the scope of the claim for patent.
14

We Claim:
1. An electromagnetic switch including; an electromagnetic solenoid (13) having coils (17) wound around a
bobbin (16) having a central hole (15) and generating an electromagnetic force for electrically
conducting a moveable contact (12) with a pair of fixed contacts (26a) upon energization, and a return
spring (14) for exerting a spring force of detaching the movable contact (12) from the fixed contacts
(26a) upon deenergization of the electromagnetic solenoid (13), in which a yoke main body (19) made
of a magnetic material and having an emd plate (19c) made of a magnetic material and opposed to the
other end of the bobbin (16) engages the electromagnetic solenoid (13), and an end wall (20) opposed
to one end of the bobbin (16) made of a magnetic material is magnetically coupled to the yoke main
body (19) so as to constitute a yoke (18) together with the yoke main body (19), the other and of the
yoke main body (19) which is clamped and fixed to a terminal holder (29) made of a non-magnetic
material having a pair of coil contact terminals (27) connected with both ends of the coil (17) and a pair
of contact connection terminals integrally having the fixed contacts being passed therethrough
respectively and sandwiching the end plate (20) relative to the other end of the bobbin (16),
a movable core (38) is in contiguous with the movable contact (12) which can be in contact with or detached from both of the fixed contacts (26a), a fixed core which is at least partially inserted in the central hole (15) and opposed to the movable core (38) in the intermediate axial direction of the central hole (15) is abutted against and positioned and fixed to the end wall (19c) of the yoke main body (19), and the return spring (14) is interposed between the fixed core (39) and the movable core (38) so as to provide a spring force of pressing and positioning the movable core (38) to the side of the terminal holder (29) upon deenergization of the electromagnetic solenoid (13).
2. An electromagnetic switch according to claim 1, wherein the fixed core (39) integrally has a bar-shaped portion (39a) inserted in the central hole (15) and opposed to the movable core (38), and a flange portion (39b) extending outward in the radial direction from one end of the bar-shaped portion (39a) and sandwiched between the end wall (19c) of the yoke main body (19) and one end of the bobbin (16).
3. An electromagnetic switch according to claim 2, wherein the yoke main body (19) is clamped and fixed to the terminal holder (29) so as to exert a force, pressing to the side of the end wall (19c) of the yoke main body (19) from the terminal holder (29) to the end plate (29) and the bobbin (16).
4. An electromagnetic switch according to any one of claims 1 to 3, wherein bottomed receiving holes (40, 41) are coaxially disposed at the opposing surfaces of the movable core (38) and the fixed core (39), respectively, and both ends of the coiled return spring (14) partially received in the receiving holes (40, 41) are abutted against the closed ends of both of the receiving holes (40,41).
5. An electromagnetic switch according to any one of claims 1 to 4, wherein the electromagnetic solenoid (13), the yoke (18), the fixed core (39), the movable core (38), and the return spring (14) are contained in a bottomed cylindrical case (44), the terminal holder (29) that closes the open end of the case (44) is
15

engaged and fixed to the case (44) so as to form a concave portion (47) facing outward in co-operation with the case (44), and a potting agent (49) is filled in the concave portion so as to bury a gap between the outer circumference of the terminal holder (29) and the case (44), and a gap between the terminal holder (29) and both of the coil connection terminals (27), and both of contact connection terminals (26).
6. An electromagnetic switch including a terminal holder or base (115) made of an insulative material, a terminal plate (117) inserted to a slit (121) formed in the terminal holder or base (115) from the inside of the terminal base (115), and an electromagnet fixed to a position facing the inner surface of the terminal base (115), in which protrusions (124,125) abutting against the base end of the terminal plate (117) are disposed to the surface of a bobbin (105) of the electromagnet facing the inner surface of the terminal base (115).
7. An electric component in which a cap member is engaged to the open surface of a case (104) containing an electric part and a liquid sealing material (127) is cast to the upper surface of the cap member to seal an engaging portion between the case (104) and the cap member, wherein an inclined surface C which is made higher at the central portion and lowered toward the outside is formed to the upper surface of the cap member.
8. An electric component according to claim 7, wherein a cap member having a terminal (115) secured thereto is engaged to the open surface of the case (104) containing an electromagnetic actuator (102), and a liquid sealing material (127) is cast to the upper surface of the cap member to tightly seal the engaging portion between the case (104) and the cap member.
9. An electric component according to claim 7 or 8, wherein the liquid sealing material (121) is cast in the vicinity of the highest portion of the inclined surface C.
Dated this 21st day of June, 2006.


ABSTRACT
An electromagnetic switch conducting on-off operation by an electromagnetic solenoid under the effect of a return spring, in which an end plate is coupled magnetically to a yoke main body made of a magnetic material engaged to an electromagnetic solenoid, a yoke main body 19 clamped to a terminal holder, a movable core is in contiguous with a movable contact, a fixed core opposed to a movable core at an axially intermediate portion of a central hole in the bobbin is abutted against and positioned and fixed to the end wall of the yoke main body, and a return spring is interposed between the fixed core and the movable core so as to urge and position the movable core 38 to the terminal holder upon deenergization, whereby the movable core size can be decreased to save electric power consumption, and the size control is facilitated.
To
The Controller of Patents
The Patent Office
Mumbai
17

Documents:

1114-MUM-2006-ABSTRACT(13-9-2010).pdf

1114-mum-2006-abstract(granted)-(3-12-2010).pdf

1114-mum-2006-abstract.doc

1114-mum-2006-abstract.pdf

1114-MUM-2006-CANCELLED PAGES(13-9-2010).pdf

1114-MUM-2006-CLAIMS(AMENDED)-(13-9-2010).pdf

1114-mum-2006-claims(granted)-(3-12-2010).pdf

1114-mum-2006-claims.doc

1114-mum-2006-claims.pdf

1114-MUM-2006-CORRESPONDENCE(13-9-2010).pdf

1114-mum-2006-correspondence(29-9-2006).pdf

1114-mum-2006-correspondence(ipo)-(6-12-2010).pdf

1114-mum-2006-correspondence-received.pdf

1114-mum-2006-description (complete).pdf

1114-mum-2006-description(granted)-(3-12-2010).pdf

1114-MUM-2006-DRAWING(13-9-2010).pdf

1114-mum-2006-drawing(granted)-(3-12-2010).pdf

1114-mum-2006-drawings.pdf

1114-mum-2006-form 1(20-9-2006).pdf

1114-mum-2006-form 18(13-7-2006).pdf

1114-mum-2006-form 2(granted)-(3-12-2010).pdf

1114-mum-2006-form 2(title page)-(13-7-2006).pdf

1114-mum-2006-form 2(title page)-(granted)-(3-12-2010).pdf

1114-mum-2006-form 26(29-9-2006).pdf

1114-mum-2006-form 3(13-7-2006).pdf

1114-MUM-2006-FORM 3(13-9-2010).pdf

1114-mum-2006-form-1.pdf

1114-mum-2006-form-2.doc

1114-mum-2006-form-2.pdf

1114-mum-2006-form-3.pdf

1114-mum-2006-form-5.pdf

1114-MUM-2006-PETITION UNDER RULE 137(13-9-2010).pdf

1114-MUM-2006-REPLY TO EXAMINATION REPORT(13-9-2010).pdf

1114-MUM-2006-SPECIFICATION(AMENDED)-(13-9-2010).pdf


Patent Number 244376
Indian Patent Application Number 1114/MUM/2006
PG Journal Number 50/2010
Publication Date 10-Dec-2010
Grant Date 03-Dec-2010
Date of Filing 13-Jul-2006
Name of Patentee HONDA LOCK MFG.CO.,LTD.
Applicant Address 3,700, AZA-WADAYAMA, SHIMONAKA, SADOWARA-CHO, MIYAZAKI-SHI, MIYAZAKI,
Inventors:
# Inventor's Name Inventor's Address
1 YUJI SHIRAGATA 3,700, AZA-WADAYAMA, SHIMONAKA, SADOWARA-CHO, MIYAZAKI-SHI, MIYAZAKI,
PCT International Classification Number H01H50/02
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 2006-026070 2006-02-02 Japan
2 2005-213912 2005-07-25 Japan
3 2005-213921 2005-07-25 Japan