U.S. patent number 3,730,489 [Application Number 05/236,070] was granted by the patent office on 1973-05-01 for hard chrome plated vibrating board of an ultrasonic-wave washer.
This patent grant is currently assigned to Hakamada Kinzoku Kogyo Kabushiki Kaisha. Invention is credited to Katsumi Morita.
United States Patent |
3,730,489 |
Morita |
May 1, 1973 |
HARD CHROME PLATED VIBRATING BOARD OF AN ULTRASONIC-WAVE WASHER
Abstract
A vibrating board for an ultrasonic-wave washer fitted to an
opening formed in the bottom of a washing tank to form a vibrating
bottom of said tank with a plurality of tremblers fixed thereto at
its under surface of the board which contacts a washing liquid in
said tank is plated with a hard chrome. Moreover, at least four
corners of the vibrating board are formed thinner than the
substantial central area of the board to which the tremblers are
attached from the below. Such construction of the vibrating board
can avoid an erosion on the board, eliminated a breakdown of the
tremblers and ensure a reliable transmission of an ultrasonic-wave
to the liquid, and thus prolongs the durable years of the vibrating
board.
Inventors: |
Morita; Katsumi
(Higashikatsushika-gun, JA) |
Assignee: |
Hakamada Kinzoku Kogyo Kabushiki
Kaisha (Edogawa-ku, Tokyo, JA)
|
Family
ID: |
22888014 |
Appl.
No.: |
05/236,070 |
Filed: |
March 20, 1972 |
Current U.S.
Class: |
366/113; 68/3SS;
134/184; 134/1; 310/26 |
Current CPC
Class: |
B08B
3/12 (20130101) |
Current International
Class: |
B08B
3/12 (20060101); B01f 011/02 () |
Field of
Search: |
;259/DIG.44,1R,72
;134/1,184 ;68/3SS ;220/64 ;310/8.3,26 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Price; William I.
Assistant Examiner: Coe; Philip R.
Claims
What is claimed is:
1. A vibrating board for an ultrasonic-wave washer fitted to an
opening formed in the bottom of a washing tank and comprising a
table portion protruding in said tank and carrying a plurality of
tremblers thereunder, a surface of said table portion contacting a
washing liquid in said tank being plated with a hard chrome; and a
flange portion integrally formed with said table portion and fixed
to the bottom of the tank.
2. A vibrating board for a ultrasonic-wave washer as claimed in
claim 1, wherein the thickness of the finished plating layer of the
hard chrome is about 20 - 30 .mu..
3. A vibrating board for an ultrasonic-wave washer as claimed in
claim 1, wherein at least four corners of the table portion and the
flange portion are formed thinner than a central area of the table
portion carrying the tremblers thereunder.
4. A vibrating board for an ultrasonic-washer as claimed in claim
3, wherein the thickness of the thinner area is about three-fourth
of that of the thicker area.
Description
This invention relates to a vibrating board for an ultrasonic-wave
washer, and more particularly to an improvement in a vibrating
board attached to the bottom of a washing tank of the
ultrasonic-wave washer especially usable for dish washing.
In such an ultrasonic-wave washer, an ultrasonic-wave is applied to
a washing liquid in the tank through vibration of a vibrating board
made of a stainless steel etc. to which a plurality of tremblers
are attached from the back. In a conventional ultrasonic-wave
washer of the type, an erosion which occurs on the vibrating board
accompanying a strong ultrasonic-wave generated in the liquid can
be hardly prevented at the present technical level in this field.
The erosion has a tendency to give a larger damage to the board,
the stronger the vibration is.
Usually, the vibrating board is made of a 18-8 stainless steel for
avoiding an erosion which, however, has sometimes a trouble of
breaking the tremblers during operation due to a difference in
coefficients of thermal expansion between said 18-8 stainless steel
and a ferrite forming the tremblers. Heretofore, in order to solve
the problem, a double coating of an aluminum plate over the under
surface of the board or other measures have been adopted. It is
most preferable to employ a titanium for the double coating, which,
however, is extremely expensive.
In analysis, the erosion on the vibrating board is found to be a
kind of evaporation of metals. When a metal hard to evaporate is
applied to the surface contacting the liquid, the advance of the
erosion can be checked to a considerable extent. Further, if the
contact face is uniformly made as smoothly as a mirror-face,
adhesion of foams to the contact face can be eliminated and a
favorable contact with the liquid assuring a good transmission of
the ultrasonic-wave can be obtained.
For further overcoming the erosion, there is an idea that the
vibrating board should be thick enough to withstand the erosion. In
this case, however, the thicker the board is, the more
deterioration of the ultrasonic-wave is observed. The stainless
steel employed for the vibrating board has a large flexural
rigidity in its property which makes it impossible to transmit a
reliable vibration to the washing liquid when the vibrating board
is made thick enough to prevent the erosion. On the other hand,
when the board is made thinner, the vibrating board easily yields
to erosion.
It is, therefore, an object of the present invention to provide a
vibrating board for an ultrasonic-wave washer which is superior in
its erosion resisting property and free from damages in tremblers,
since the vibrating board has little difference in a coefficient of
thermal expansion from the tremblers made of a ferrite.
It is another object of the present invention to provide a
vibrating board for an ultrasonic-wave washer which can transmit a
vibration of the vibrating board uniformly and effectively to a
washing liquid and overcome a flexural rigidity of the board, even
though employing a thick material enough to withstand the
erosion.
Essentially according to the present invention, there is provided a
vibrating board for an ultrasonic-wave washer fitted to an opening
formed in the bottom of a washing tank and comprising a table
portion protruding in said tank and carrying a plurality of
tremblers thereunder, a surface of said table portion contacting a
washing liquid in said tank being plated with a hard chrome; and a
flange portion integrally formed with said table portion and fixed
to the bottom of the tank.
Various, further, specific objects, features and advantages of this
invention will be described by way of example with reference to the
accompanying drawings illustrating a preferred embodiment of this
invention, in which;
FIG. 1 is a longitudinal sectional view of a washing tank of an
ultrasonic-wave washer provided with a vibrating board according to
this invention;
FIG. 2 is a sectional view of the vibrating board;
FIG. 3 is a perspective view of a vibrating board having all the
four corners of a table and a flange portion thereof planed
thinner; and
FIG. 4 is a sectional view taken on a line IV--IV of FIG. 3.
Referring now to FIG. 1, a washing tank 1 has a large opening 1b in
its bottom 1a. A vibrating board 2 of 18-8 stainless steel is
attached to the washing tank from outside in such a manner that a
table portion 2a of the vibrating board 2 protrudes in said tank 1
through said opening 1b. Said vibrating board 2 is fixed to the
bottom 1a of the washing tank 1 by way of its flange portion 2b,
through a packing member 3 provided therebetween, with bolts and
nuts 4.
Tremblers 5 are fixed to the under surface of the table portion 2a
of the vibrating board 2.
As shown in FIG. 2, the vibrating board 2 consists of a base plate
21 of 18-8 stainless steel and a plated layer 22 of a hard chrome
in the thickness of 20 - 30 .mu..
Further in order to overcome a trouble of erosion, the vibrating
board may preferably be made of a thick material. However, as
stated hereinbefore, the stainless steel employed for the vibrating
board has a large flexural rigidity in its property which makes it
impossible to transmit a reliable vibration to the washing liquid,
when the material is made rather thick. This problem can be settled
by making at least the four corners of the table portion 2a and the
flange portion 2b thinner than the central area of the table
portion as illustrated in FIGS. 3 and 4. In this case, the four
corners of the table 2a and the flange portion 2b of the vibrating
board 2 are planed thinner prior to pressing so as to be about
one-fourth thinner than the central area of the table portion 2a
which is thick enough to withstand erosion. The thickness of the
thicker central area of the table portion 2a is preferably 1.2 -
1.6 mm though it varies depending on the capacity of the washer and
the number of the tremblers. Alternatively, the entire
circumference of the table portion 2a except the central area and
the entire flange portion 2b may be formed thinner.
After planing is completed, a step is made in the vibrating board 2
to form the table portion 2a and the flange portion 2b in the
process of pressing.
The present vibrating board with at least the four corners of the
table portion and the flange portion thereof planed thinner than
the central area of the table portion 2a to which the tremblers 5
are attached can offer a powerful sound field in the liquid in the
washing tank and, at the same time, can eliminate a breakdown by
erosion, since the substantial portion of the board is formed
thick. If two washing tanks having the same capacity but provided
with different vibrating board, namely, the conventional one and
the present one are operated employing the same ultrasonic-wave
oscillator, the present vibrating board can produce far stronger
sound field than the conventional board. Therefore, in order to
produce a determined sound field, the output power of the
oscillator can be smaller in combination with the present vibrating
board advantageously from the economical point of view.
As set forth hereinabove, the vibrating board for an
ultrasonic-wave washer according to this invention has various
advantages that the plating of a hard chrome over the surface
thereof can highly elevate an erosion resisting property of 18-8
stainless steel and eliminate damages in tremblers since a
stainless steel plated with a hard chrome has little difference in
a coefficient of thermal expansion from the tremblers made of a
ferrite. Moreover, the surface of the vibrating board is formed so
smoothly with a hard chrome plating that a favorable transmission
of the ultrasonic-wave can be assured.
Further advantages of the present invention are that the thicker
substantial area of the vibrating board can fully avoid an erosion
on the board, thus prolonging its span of life and that,
notwithstanding, the present vibrating board can offer a powerful
sound field in the tank with its thinner circumferential area.
* * * * *