JPS5492701

Patent Translate
Powered by EPO and Google
Notice
This translation is machine-generated. It cannot be guaranteed that it is intelligible, accurate,
complete, reliable or fit for specific purposes. Critical decisions, such as commercially relevant or
financial decisions, should not be based on machine-translation output.
DESCRIPTION JPS5492701
DESCRIPTION OF THE PREFERRED EMBODIMENTS 1. Pick-up 1 according to the invention In a
pick-up having an armature movably mounted in a space defined by a fixed member and passed
by magnetic field lines, said armature or rigidly coupled thereto Pickup characterized in that the
part is at least partially intercalated by a liquid comprising in its suspension some 10
ferromagnetic particles which are sufficient to keep the suspension in said space.
2, the scope of claims
3. Detailed Description of the Invention The present invention relates to a pickup having an
armature movably mounted in a space defined by a fixed member and being passed by magnetic
field lines. In many pick-up constructions the armature is supported by a piece of rubber in the
form of a pad in the case of a flat armature or by a piece in the case of a bushing in the case of a
rod-like armature. The rubber member is for the dual purpose of establishing a restoring force
that allows the amateur to return to a properly defined neutral position after deflection and for
damping the amateur's vibration to provide a smooth frequency response. To work. However, the
specific properties required to optimize the decay effect EndPage: 1 are different from what is
desired with regard to pickup compliance and follow-up ability, so that in part 5 contradictory
considerations I can not but accept the compromise of The object of the present invention is to
provide a pickup of the type mentioned, in which the armature receiver is provided with a
separate damping stage IO stage which is independent of the element, so that no compromise is
required. This object is achieved according to the invention by means of a pickup device, in
which case the armature or the part rigidly connected to it is [enough to hold the five
suspensions in the space mentioned above] The ferromagnetic particles are at least partially
intercalated by the liquid contained in the suspension. In such a structure, the ferrofluid
constituted by the suspension 20 supports the vibration of the movable device, the nature of the
01-05-2019
1
element is other properties of the pickup such as compliance and compliance. It can be chosen to
optimize. The damping effect can be adjusted as desired by appropriately selecting the viscosity
of the ferrofluid. In a conventional pick-up where the armature is relatively flat and windingoriented, said space is formed by an air cap between the faces of two opposite poles, According
to the invention, the suspension can bridge the air gap between the faces of said poles as
appropriate. According to another embodiment of the pickup according to the invention, the
space is in this case defined by a tubular magnet with pole pieces at the end, the space being
substantially filled with the suspension ing. The invention will be further described below with
reference to the drawings. In FIG. 1, the permanent magnet 10, the rear yoke 11, the generally
cylindrical pole piece 12 and the front yaw 13 form a magnetic circuit 1, which further
comprises one end of the pole piece 12 and the back side of the lower end of the front yoke. And
an air gap 14 defined in the interval 5.
A magnetic, flat, square or square armature 15 fixed to the inner end of the stylus arm 16 and
equipped with a winding (not shown) is pivotally mounted in the air gap. The stylus 10 extends
through a step 17 in the front yoke 13 and has a stylus at its outer end. In the bore 18 in the free
end of the pole piece 12, the sleeve 19 is held firmly by means of a screw 20 which is screwed
into a threaded bore 15 extending radially from the bore 18. The nickel coating 21 of the wire
22 is fixed to the inside of the sleeve 19. The nickel coated wire extends inwardly of the inner
end of the stylus arm 16 and is fixed 20 h thereupon. A cover disc 23 made of plastic or elastic
material is attached to the end face of the pole piece 12, and between the disc 23 and the
armature 15 is a central hole for storing the nickel-coated wire 21.22. The rubber pad 24 is
compressed by the tension of the wire 22. In a small area 25 close to the inner surface of the
armature 15, the nickel coating 21 is interrupted to provide a pivot point so that the armature
can pivot in any direction. In the air gap, some ferrofluid 26 consisting of a colloidal suspension
of irregularly shaped small ferromagnetic particles in a liquid carrier such as a synthetic
hydrocarbon is responsible for the cohesion of adhesion forces. By the magnetic field. Due to
magnetic leakage, the ferrofluid extends along the sides of the pole piece for a limited distance as
shown. The fluid 26 provides damping of the vibration of the moveable device consisting of the
armature 15 and the stylus arm 16, so a rubber pad 24 without internal damping effect can be
used. EndPage: 2 The degree of damping obtained is dependent on the viscosity of the ferrofluid,
which can be chosen according to the practical requirements. The embodiment shown in FIG. 2
preferably comprises a tubular, permanent magnet 30 in the form of a samarium 5-mocobalt
alloy, the lower part of which is a flat lower surface which forms an angle with the axis 32 of the
magnet. It is cut off leaving 31. Attached to each section of the magnet are yaws 33 and 34,
respectively, made of iron or other magnetically conductive material. The yoke 33 is a so-called
cylindrical body having an annular flange 35 at one end, one side of this annular flange being 15
isomorphic to the adjacent end face of the magnet 30 and engaging therewith. The yoke 33
further comprises a frusto-conical axial projection 36 which extends from the circular inner edge
of the magnet 300 into the cavity 37 defined by the magnet.
01-05-2019
2
A movable device similar to that shown in FIG. 1, consisting of an armature 20, a stylus arm and
a nickel-coated Biano wire 21.22, in a manner similar to that described above with respect to FIG.
That is, it is supported by the annular rubber pad 24, the hole 18 in the yoke and the screw 20.
The stylus arm 16 extends through an opening 38 in the front yoke 34. The front yoke 34 is
disc-shaped and has an inner annular surface which conforms to and engages the adjacent end
face of the magnet 30. The front yoke as well as the rear yokes 3.5 have a frusto-conical inwardly
extending abutment A9 which together with the first projection 36 define an air gap in which the
armature is described above It is pivotally mounted by means of The cavity 37 is filled with a
ferrofluid 40 of the type described above. The damping fluid is retained within the cavity
regardless of the aperture 38 by the combination of the action of the magnetic field on the
suspended particles and the effect of the fluid calendar on the adjacent solid member. The
invention is illustrated in the drawings and is not restricted to the specific embodiments
described above. For example, the damping effect is caused by a wing fixed in the stylus arm and
movable in five separate spaces which are passed by magnetic field lines, or in the case of a
magnetic pick-up by a wing fixed to a rod-like moving magnet I can do it. Also, taking into
account the fact that the armature is released from the function of damping, the rubber pad 024
should be eliminated by making the piano line 22 sufficient to carry the pickup. It is possible.
Many other variations are possible within the scope of the present invention.
4. Brief Description of the Drawings 5 FIGS. 1 and 2 show vertical longitudinal sections of
respective embodiments of the pickup according to the invention. [Description of sign of main
part] Magnet 10; 30.0 pole piece 12 yoke 11. 13; 33. 34 space (air gap) 14: 37 amateur 15
suspension 26; 40 stylus arm 16 agent Masao Okabe Yasui −-15, ・ ++ ノ 一 パ パ 轡 轡 一 轡 一
義 上 義-],---"EndPage: 3
01-05-2019
3