U.S. patent number 3,783,430 [Application Number 05/256,153] was granted by the patent office on 1974-01-01 for contactless switching apparatus.
This patent grant is currently assigned to Denki Onkyo Co., Ltd.. Invention is credited to Masasi Kuroyanagi, Seishiro Nishiba, Koichi Ogawa.
United States Patent |
3,783,430 |
Nishiba , et al. |
January 1, 1974 |
CONTACTLESS SWITCHING APPARATUS
Abstract
A contactless switching apparatus comprised of a magnetic strip
both ends of which are bent to form opposed terminal portions, a
magnetic piece which is fitted in said strip and is attracted at
its both ends by said bent terminal portions, a supporting member
which fixes either the strip or the magnetic piece to a base and
hold it at a position a certain distance away from the base, an
actuating means which actuates the rest, which is not fixed at the
base, of the strip and magnetic piece and galvano-magneto effect
devices which are provided at the ends of the fixed magnetic
member, wherein the magnetic field intensity applied to the device
is varied with movement of the movable magnetic member actuated by
said actuating means.
Inventors: |
Nishiba; Seishiro (Tokyo,
JA), Kuroyanagi; Masasi (Tokyo, JA), Ogawa;
Koichi (Yokohama, JA) |
Assignee: |
Denki Onkyo Co., Ltd. (Tokyo,
JA)
|
Family
ID: |
12632163 |
Appl.
No.: |
05/256,153 |
Filed: |
May 23, 1972 |
Foreign Application Priority Data
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|
|
|
May 24, 1971 [JA] |
|
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46/42300 |
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Current U.S.
Class: |
338/32H;
338/32R |
Current CPC
Class: |
H03K
17/97 (20130101); H03K 17/972 (20130101) |
Current International
Class: |
H03K
17/94 (20060101); H03K 17/97 (20060101); H03K
17/972 (20060101); H01c 007/16 () |
Field of
Search: |
;338/32R,32H ;323/94H
;324/45,46 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Albritton; C. L.
Attorney, Agent or Firm: James E. Armstrong et al.
Claims
What is claimed is:
1. A contactless switching apparatus comprising:
a. A magnetic strip having a pair of ends bent to form opposed
terminal portions,
b. a magnetic piece having a pair of ends, inserted between the
terminal portions of said magnetic strip, each of said ends
respectively opposing a different one of said terminal portions and
being separated therefrom by a gap, said magnetic piece and said
magnetic strip being reciprocally displaceable along a
predetermined path, one of said magnetic piece and said magnetic
strip being a fixed magnetic member and the other being a movable
magnetic member,
c. a base,
d. a supporting member attached between said base and said fixed
magnetic member to provide a space therebetween,
e. at least one galvano-magneto effect device within one of said
gaps formed between said magnetic strip and said magnetic piece,
wherein said galvano-magneto effect device is positioned in the
flux path between the magnetic strip and the magnetic piece,
f. a depressible push button actuating means adapted to displace
along said pre-determined path said movable magnetic member whereby
the magnetic flux density through said galvano-magneto effect
device is changed.
2. An apparatus according to claim 1, wherein said depressible push
button actuating means is provided with a mounting portion for
holding the movable magnetic member.
3. An apparatus according to claim 2, wherein the mounting portion
is comprised of a plurality of pins between which the movable
magnetic member is fixed.
4. An apparatus according to claim 2, wherein the mounting portion
is comprised of a pair of oppositely-arranged walls, the fixed
magnetic member being disposed in the space formed therebetween,
the walls having on the internal surfaces thereof recesses for
slidably engaging the supporting member.
5. An apparatus according to claim 2, wherein the mounting portion
is a peripherally enclosing wall forming an open-ended cavity in
the push button actuating means, the ends of the magnetic strip are
fixed at the lower end of the peripherally enclosing wall and the
magnetic piece is positioned in the open-ended cavity of the push
button actuating means.
6. An apparatus according to claim 3, wherein the mounting portion
is provided with a receiving member supporting the movable magnetic
member.
7. An apparatus according to claim 6, wherein the receiving member
is a block at the center of which is a groove receiving the
magnetic piece.
8. An apparatus according to claim 7, wherein through holes for
securing the pins of the push button actuating means are provided
at both sides of the groove and a cut-off window is provided at the
center of the bottom of the groove to slidably receive therein the
supporting member.
9. An apparatus according to claim 7, wherein through holes into
which the pins of the push button actuating means are fixed are
provided at both sides of the groove and recesses along which the
supporting member slides are provided at both sides of the center
of the groove.
10. An apparatus according to claim 1, wherein the magnetic strip
is fixed by the supporting member so that the terminal portions are
positioned to face the base and the magnetic piece is movably
positioned in the space between the magnetic strip and the
base.
11. An apparatus according to claim 1, wherein a cushion member is
provided at at least one of the magnetic strip and piece so that
the cushion member is positioned between the magnetic strip and
piece when the magnetic strip is attracted to the magnetic
piece.
12. An apparatus according to claim 1, wherein a guide frame is
provided at the base so that the direction of movement of the
movable magnetic member is controlled.
13. An apparatus according to claim 12, wherein the guide frame is
comprised of a pair of opposed guide plates, the mounting portion
of the push button actuating means is inserted into a space formed
between said guide plates and moves vertically therebetween with
the mounting portion keeping light contact with the internal
surfaces of the opposed guide plates.
14. An apparatus according to claim 12, wherein the guide frame is
comprised of a pair of opposed guide plates and a receiving member
is inserted into a space formed between said guide plates and moves
vertically while keeping light contact with the internal surfaces
of the guide plates.
15. An apparatus according to claim 12, wherein the guide frame is
comprised of a pair of conductive guide plates, lead wires of a
galvano-magnetro effect device are connected respectively to said
guide plates and the guide plates are connected respectively to an
electrical circuit provided at the base.
16. An apparatus according to claim 15, wherein the base includes a
printed circuit.
17. An apparatus according to claim 1, wherein the magnetic piece
is the movable magnetic member and composed of a magnet and the
magnetic strip is the fixed magnetic member.
Description
BACKGROUND OF THE INVENTION
The present invention relates to a contactless switching apparatus
employing a galvano-magneto effect device.
Conventional switching apparatuses of this type have been provided
with a magnetic path formed by combining the magnetic fixed yoke
and the magnetic movable yoke and the reluctance of the magnetic
path has been varied by shifting the movable yoke actuated with an
actuating means such as a push button. The intensity of the
magnetic field acting on the galvano-magneto effect device has been
changed with variation of this reluctance to generate the output
signal. Accordingly, conventional switching apparatuses are
disadvantageous in the following points.
Since a plural number of yokes are required, the parts required
increase in number, the production cost is high and assembly work
is troublesome and complicated. Since the magnetic path becomes
large in size, the entire apparatus cannot be compacted.
Generally, the actuating means of a conventional apparatus is
required to have a resetting spring. Therefore, the production cost
is high and the assembly work troublesome.
The present invention provides a switching apparatus which
eliminates the above disadvantages.
SUMMARY
A contactless switching apparatus comprising a high magnetic
permeability strip both ends of which are bent to form a pair of
terminal portions, a magnetic piece such as, for example, a
permanent magnet having magnetic poles at its both ends which is
fitted between the terminal portions of said strip so that both
ends of the magnetic piece are opposed respectively to said
terminal portions of the strip with a gap at each side, a
supporting member provided at one of said strip and magnetic piece,
an actuating means provided at either the strip or the magnetic
piece at which the supporting member is not provided, and a
galvano-magneto effect device such as, for example, a Hall effect
device or a magneto-resistance effect device which is fixed at at
least one end of the strip or the magnetic piece at the side where
said supporting member is provided so that the device is located in
said gap, wherein the supporting member is made and arranged so
that the magnetic member supported by said supporting member is
fixed at the base and the magnetic member is held with a specified
space between the magnetic member and the base, and said actuating
means is designed so that it may be isolated from the magnetic
member at the fixing side by shifting said magnetic member held as
above if desired, thereby the movable magnetic member provided with
the actuating means is secured while being attracted at both ends
by the fixing side magnetic member always held with the supporting
member, is released from the fixing side magnetic member against
the attracting force active on the fixing side magnetic member when
actuated by the actuating means while being kept parallel with the
fixing side magnetic member, and is reset to the home position by
attraction to the fixing side magnetic member when released from
the actuating means and said galvano-magneto effect device is
connected to the load which detects a galvano-magneto effect to
detect the variation of the output when the intensity of the
magnetic field applied to the device is varied by action of the
moving side magnetic member and the output of the device is
therefore varied.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention is illustrated in detail by the accompanying
drawings wherein:
FIG. 1 is a front view of the apparatus according to the present
invention,
FIG. 2 is a sectional view as seen along line 2--2 in FIG. 1,
FIG. 3 is a sectional view as seen along line 3--3 in FIG. 1,
FIG. 4 is isometric views of disassembled parts of the apparatus
shown in FIG. 1,
FIG. 5 is a front view showing another embodiment of the
apparatus,
FIG. 6 is a sectional view as seen along line 6--6 in FIG. 5,
FIG. 7 is a sectional view as seen along line 7--7 in FIG. 5,
FIG. 8 is an isometric view of a receiving member employed in the
apparatus shown in FIG. 5,
FIG. 9 is an isometric view illustrating another embodiment of said
receiving member,
FIG. 10 is an isometric view illustrating an embodiment of a push
button employed in the apparatus,
FIG. 11 is a horizontal sectional view of a switching apparatus
employing a push button shown in FIG. 10,
FIG. 12 is a front view illustrating another embodiment of the
apparatus,
FIG. 13 is a cutaway side view of the apparatus shown in FIG.
12,
FIG. 14 is a circuit diagram of the apparatus employing the
galvano-magnetro effect device, and
FIG. 15 is a circuit diagram of the apparatus employing the Hall
effect device.
DETAILED DESCRIPTION
Referring to FIGS. 1 to 4, there is shown a switching apparatus
comprised of actuating means 10 employing a push button made of a
non-magnetic material, a magnetic piece 20 such as, for example,
permanent magnet which is vertically moved by said actuating means,
magnetic strip 30 into which said permanent magnet is fitted,
supporting member 40 which supports said strip 30, galvano-magneto
effect device 50 provided at said strip, guide frame 60 for
movement of said magnetic piece, and base 70 such as, for example,
a printed board on which said supporting member 40 and guide frame
60 are mounted.
Guide frame 60 is formed with a pair of U-shaped guide plates 61
and 61' made of a conductive material and a pair of said guide
plates are mounted on base 70 so that a square space is formed
between the guide plates by oppositely arranging bent free end 611
and 611'.
Base 70 is provided with through holes 71 at positions where said
guide plates are mounted and the guide plates are provided with
claws 612 and 612' at positions corresponding to through holes 71,
thereby the guide plates are fixed at the base by inserting the
claws into through holes 71 and securing them.
Strip 30 is fixed at the space in guide frame 60 while being
supported by supporting members 40. Strip 30 is made of a high
permeability magnetic material and its both ends in the lengthwise
direction are bent to form terminal portions 31 which are opposed
each other. Strip 30 is inserted into the guide frame in the
position that said terminal portions face base 70.
Supporting members 40 are provided at both sides in the center
portion of strip 30 with the end portions of said supporting
members being inserted into through holes 72 provided at base
70.
Accordingly, strip 30 is held to oppose base 70 through a space
with a specified height.
Permanent magnet 20 is fitted into the underside of strip 30 so
that the permanent magnet can be slid vertically in a space between
supporting members 40.
Permanent magnet 20 is magnetized so as to have magnetic poles N
and S at its both ends and these pole ends are assembled with strip
30 so that the pole ends are opposed respectively to terminal
portions 31 of strip 30 with gap G at each side. Accordingly,
permanent magnet 20 is secured while its pole ends are usually
attracted to the terminal portions of strip 30.
Permanent magnet 20 is operated by push button 10. Push button 10
is provided with mounting portions such as, for example, four pins
11 which are extended to both sides of strip 30. Accordingly, strip
30 is housed in space 12 formed inside said pins 11.
Pins 11 are arranged so that they can slide along the internal
surfaces of guide plates 61 and 61' of guide frame 60 and therefore
movement of push button 10 is directionally controlled by guide
plates 61 and 61'.
Permanent magnet 20 is fixed at the lower ends of pins 11 of push
button 10 with a bonding agent. Therefore, push button 10 is kept
at the upper limit position due to that permanent magnet 20
attracts strip 30.
Galvano-magneto effect device 50 such as, for example, a
magnetro-resistance effect device is fixed at the inside surface of
at least one terminal portion 31 of strip 30 so that the device is
opposed to one magnetic pole of permanent magnet 20.
Leads 51 are respectively connected to two electrodes of device 50
and are further connected to guide plates 61 and 61'
respectively.
Since guide plates 61 and 61' are made of a conductive material,
the device can be connected to detection circuit such as, for
example, printed circuit 80 using the guide plates as the terminals
by soldering claws 612 and 612' to the printed circuit of base
70.
Circuit 80 can be formed as desired. For example, device 50 and
load 81 should be connected in parallel with supply V as shown in
FIG. 14 if the magneto-resistance effect device is employed as the
device, and load 81 should be connected to output terminal 52 of
the device as shown in FIG. 15 if the Hall effect device is
employed as the device.
In FIG. 14, if load 81 is a transistor, device 50 can be connected
to the base of the transistor to control the function of the
transistor with variation of the resistance of the device.
The switching apparatus as the embodiment of the present invention
is as described above. When push button 10 is depressed, magnet 20
is lowered away from strip 30. When magnet 20 is lowered, the
closed magnetic path formed by magnet 20 and strip 30 is opened.
Therefore, the magnetic flux density applied to device 50 is
reduced to decrease the internal resistance of the device.
When push button 10 is released, magnet 20 is reset with attraction
onto strip 30 and the magnetic flux density applied to the device
increases to cause the internal resistance of the device to
increase. Accordingly, the output of the device varies with
operation of push button 10, thus making it possible to perform the
switching operation.
The apparatus can be constructed as described below. It is
desirable to attach cushion member 90 such as, for example, a
rubber plate to the surfaces of strip 30 and magnetic piece 20. For
example, as shown in FIG. 2, if rubber plates 90 and 90' are
provided at the upper and lower surfaces of strip 30, magnet 20 and
push button 10 are buffered in their movement, and the relative
position of the moving side magnetic member, that is, magnetic
piece 20 shown in the embodiment to the terminal portion of said
strip can be adjusted in accordance with the thickness of rubber
plate 90'. At least one of magnetic piece 20 and strip 30 are
preferred to have a magnet; for example, a magnet can be employed
in strip 30.
The magnetic piece which is actuated by actuating means 10 need not
be fixed directly to the actuating means. For example, as shown in
FIGS. 5 to 7, non-magnetic receiving member 100 can be attached to
the push button mounting portion such as, for example, pins 11 and
magnet 20 can be retained by this receiving member 100. The
embodiment of said receiving member 100 is shown in FIGS. 8 and 9.
The receiving member shown in FIG. 8 is a non-magnetic block
provided with groove 101 into the center of which the magnet is
fitted, through holes 102 into which pins 11 are inserted at both
sides of groove 101 and cut-off window 103 into which supporting
member 40 can be slid at the center bottom of the groove. This
receiving member is employed in the apparatus shown in FIG. 5.
The receiving member shown in FIG. 9 is such that both sides of the
center of groove 101 are chipped and supporting member 40 slides
along the chipped portions, thus forming slide recess 104. This
receiving member is used as that shown in FIG. 8.
The mounting portion of said push button 10 can be formed with a
pair of opposed walls 13 and 13' as shown in FIG. 10. In this case,
the fixing side magnetic member is provided in the space between a
pair of walls as shown in FIG. 11 and recesses 131 along which
supporting member 40 slides are provided at the internal surfaces
of walls 13 and 13'.
Either magnetic piece 20 or strip 30 can be fixed.
As shown in FIGS. 12 and 13, strip 30 is attached to push button as
the moving side and magnetic piece 20 can be fixed at base 70 with
supporting member 40. In this case, terminal portions 31 of strip
30 are projected upwardly because strip 30 moves vertically and
magnetic piece 20 is housed in cavity 14 formed in the push button
when the push button is lowered.
In this embodiment, the mounting portion is formed with peripheral
wall 15 inside which cavity 14 is formed and the peripheral wall is
arranged to lightly contact the guide plates to improve directional
control of movement.
In this type of the apparatus, since the push button is provided
with the strip, the total weight of the push button and strip is
reduced and the magnetic piece can be large and a large magnet can
be employed as the fixing side magnetic member.
In the above embodiments, each area of the terminal portions of the
strip and the end portions of the magnetic piece which form the gap
in which the device is located is preferred to be larger than that
of the device and the magnetic piece preferably projects from the
terminal portions as shown in FIG. 2 to improve the resetting
ability.
If the fixing side magnetic member is employed as the strip as
shown in FIG. 1, supporting member 40 can be made integral with the
strip but can be independent of the strip, depending on the case.
If the magnet is employed as the fixing side magnetic member, the
non-magnetic supporting member is generally employed.
Since the apparatus according to the present invention is as
described above, it provides the following advantages when
employed.
The resetting means such as, for example, a spring is not required
because the moving side magnetic member is secured by being
attracted to the fixing side magnetic member.
Because the magnetic path is formed by fitting the magnetic piece
into the strip, the magnetic path can be compact in size and since
the magnetic path can be formed with the magnetic piece and strip
only, the parts employed can be reduced in number and assembly work
is easy.
Because the magnetic path is opened and closed with mutual approach
and departure of the strip and the magnetic piece which are kept in
parallel, the stroke of the moving side magnetic member can be
small and the terminal portions of the strip and the end portions
of the magnetic piece approach each other or depart from each other
at the same time; therefore, the reluctance of the magnetic path
greatly varies and correspondingly the magnetic flux density
applied to the device.
The apparatus according to the present invention iss useful as the
contactless switching apparatus for which the demand will increase
more and more in the future for the advantages described above.
* * * * *