close

Вход

Забыли?

вход по аккаунту

?

Патент USA US3092807

код для вставки
June 4, 1963
P. BECKMAN
3,092,798
HALF-BRIDGE TEMPERATURE COMPENSATING DEF'LECTION SENSOR
Filed July l0, 1961
ma
ï
26
26
¿9
/Z
/
9/
24
zok/
1NVEN T_OR.
Pa u/ Beckman
BY f /lîêë
for/7@
United States Patent ¥Oñïice
l
31,092,798
Patented June 4, 1963
2
3,092,798
terminal 2 of FIG. l may have its ends bent as at 17,
Paul Beckman, 944 Henrietta Ave.,
Huntington Valley, Pa.
Filed July 10, 1961, Ser. No. 122,848
5 Claims. (Cl. 338-2)
FIG. lA, to receive the filaments 4 and 7 without requir
ing such filaments to be bent at right angles as shown
in FIG. l.
A gage ofthe type shown in FIG. l may perform the
function »of determining bending strains in any desired
structure simply by placing the longitudinal axis of the
This invention relates to bonded electrical resistance
filament-type strain gages that are especially adapted to
gage on the neutral axis of the structure with the fila
ments disposed on the opposite side of such axis so that
the filaments are respectively subjected to tension and
HALF-BRIDGE TEMPERATURE COMPENSATING
DEFLECTION SENSOR
high temperature operation.
_
It is an object of my invention to provide an improved
gage of this type that is so constructed and arranged
that it can be manufactured relatively economically 1n
compression during bending. With the three leads 1,
5, and 8 connected in adjacent arms of a bridge the elec
trical outputs `off the two filaments when subjected to
tension and compression strains is additive as Well as
sub-miniaturized form while still obtaining a necessary 15 affording temperature compensation.
degree of accuracy and sensitivity combined with relative
ruggedness for a device of such minute size.
Other objects and advantages will be more apparent
The construction
of this gage with the relatively strong T-frame type of
center lead is highly conducive to providing a rugged
sub-miniaturized gage as well as insuring a relatively
to those skilled in the art from ‘the following description
economical construction for manufacture. The filaments
of the accompanying drawings in which:
20 4 and 7 are preferably of Well-known electrical strain
FIG. l is a greatly enlarged longitudinal sectional View
sensitive wire although obviously such filaments may
of one form of my improved gage;
have different cross-sectional configurations such as being
` FIG. lA is an enlarged detail of a modified terminal
end of the gage of FIG. l;
FIG. 2 is a T-frarne of modified form of gage;
FIGS. 3 and 3A respectively show strain gage and
flat in case the filaments are made -ot‘ well-known foil.
The gage shown in FIG. l is not, of course, limited in
its use for determining bending strains as it can be laid
on the surface of a test specimen for determining tension
temperature compensating filament and lead units, per
or compression strains therein. The gage assembly is,
se, ofthe FIG. 2 form of gage; -
of course, cemented to the test specimen in the usual
and >well-known manner by using usual ceramic cements
FIGS. 4 and 4A show the successive steps by which the
temperature compensating filament is supported in an un 30 for high temperature application.
The gage shown in FIG. 5` is of the half-bridge configu
ration, as is also broadly the case with FIG. l. However
in FIG. l if a gage is used for measuring just tension (or
their leads at one end bent preparatory to being ass-em
compression) strains, there is no temperature compensa~
35 tion, whereas in FIG. 6 temperature compensation is
bled on the T-frame of FIG. 2.
FIG. 6 shows the fully assembled and completed gage
obtained by having a strain-responsive filament 24) and
made from the parts shown in FIGS. 2 to 5A.
an untaut temperature compensating filament 2l. The
In FIG. 1 I have shown a T~shaped metal frame con
construction of this gage broadly includes the smc T-type
sisting of a center tube 1 and a lateral terminal in the
frame consisting of a metallic center tube lead 22 prefer
form of a cross tube 2 secured to the center tube by 40 ably liattened throughout its length and a laterally ex
silver soldering 3 or by spot welding. This center tube
tending -cross terminal support 23 welded, silver soldered,
taut state;
Y
4
'
FIGS. 5 and 5A show respectively the temperature
compensating filament and strain-sensing filament with
serves not only as the main frame member but also as
the center electrical lead. A strain-responsive electrical
resistance filament 4 has one end inserted into the tubular
terminal 2 which is thereupon swaged fiat to pinch the
filament for holding the same. The Iother end of the
filament is similarly inserted in a metallic tubular lead 5
and held thereto by swaging the end 6. A similar strain
responsive filament 7 is secured in the other end of the
or otherwise secured to the end Iof the center lead 22.
The two filaments 20 and 21 are of the same length as
shown in FIGS. 3 and 3A and the ends of each are in
serted in tubular leads 24, 2S, 26 and 27 whose ends are
then swaged fiat to hold the filaments. To produce the
untaut -condition of filament 21 the lead 26 is passed
through a tube of insulation 28 preferably of silica and
secured thereto near one end of the filament by a cap of
cross terminal 2 and to a lead 8. In this particular form 50 ceramic cement 29. The insulator tube 28 is sufficiently
of gage it is desirable to have the two filaments substan
shorter than the filament so that upon inserting the lead
tially equally spaced from and parallel to the longitudinal
27 into the end of insulator tube 28 the ñlament 21 takes
axis of the gage which in this case would be the axis of
an untaut wavy condition. The lead 27 and tube 28 are
tube 1 and also to provide an insulator that will prevent
then secured together by a ceramic cap 29’. In the next
any possibility of the filaments being electrically shorted 55 step as shown in FIGS. 5 and 5A the terminals 24 and
by contacting the metallic center tube. l accomplish
26 are reversely bent as at 31 and 32 preferably at a slight
this by providing a tube of insulation 11 enclosing the
angle as shown. These bent leads are then hooked
tubular lead 1 from a point adjacent the cross terminal
over the cross terminal support 23 and welded or other
2 to a point 12 preferably beyond the other end of the
wise suitably secured thereto as shown in FIG. 6. The
filament, while the desired uniform spacing of the fila 60 bent ends 31 and 32 may then be cut ofi if desired. The
ments at the lead end of the gage is obtained by insulat
ing tubular spacers 13 and 14 through which the laterally
leads 25, 27 and 22 are then held in spaced relation as
shown while a ceramic coating 34 completely encases
the entire structure.
disposed leads 5 and 8 extend. These spacers are prac
tically in contact with center insulating tube 11 and are
It will, of course, be understood that various changes
of such size that the filaments 4 and 7 are positioned 65 in details of construction and arrangement of parts may
be made by those skilled in the art without departing
substantially parallel to each other and to the gage axis.
from the spirit of the invention as set forth in the ap
All insulator tubes are preferably made of silica. The
pended claims.
entire structure thus far described is enveloped or en
I claim:
cased in a coating of usual ceramic cement 15 that covers 70
l. An electrical resistance-type strain gage having a
and thus binds together portions 16 of all leads so that
everything is firmly fixed together. If desired, the cross
frame comprising a longitudinally extending metallic
center lead and a separate metallic frame member
3,092,798
mechanically and electrically connected to one end of
the center lead and extending laterally thereof, said lateral
frame having a tubular portion extending along one side
tot the center lead substantially in the same longitudinal
direction as the center lead, an electrical strain-responsive
filament connected directly into said axially extending
tubular portion and extending substantially parallel to
tions of the other leads, tubular spacers disposed over
said adjacent portions of said other leads to maintain
them a predetermined distance from the center lead so
that the filaments are substantially parallel to each other,
and said coating of insulation extends entirely over said
spacers and over a portion of the center lead adjacent
to said spacers as well as over a portion of the lateral
said center lead, a lead connected to the other end of
leads, and a ceramic coating covering the cross member,
metallic center lead, a cross member secured to oneend
of said «center lead to form a T-shape frame, a pair of
iilaments disposed substantially parallel to said center
filaments and leads to form a unitary structure thereby
said filament and being disposed adjacent to said center
lead, and a casing of cement enveloping the filament and 10 to form a unitary structure.
4. A strain gage comprising a longitudinally extending
leads to hold them together as a unit.
metallic center' lead, a cross member secured lto one end
2. A strain gage comprising a longitudinally extending
of said center lead to form a T-shape frame, a pair of
filaments disposed substantially parallel to said center 15 lead «on opposite sides thereof and connected at one of
lead on opposite sides thereof and connected at one of
their ends to said cross member, leads connected to the
their ends to said cross member, leads connected to the
other ends of said filaments and disposed adjacent to and
other ends of said filaments and disposed adjacent to and
laterally of the center lead, said cross member being of
laterally of the center lead, said center lead and cross
member being of tubular form and the ends of the cross
tions of the other leads, and a ceramic coating covering
iilaments extend along a straight line into such lbent ends
of the cross member, and a ceramic center covering the
tubular form into Whose ends the filaments are disposed 20 member are ben-t to extend in the same direction as the
longitudinal axis of the center lead and toward the leads
and held therein, an insulator tube extending over said
at the other end of the center lead so that the ends of the
center lead from the cross member to the adjacent por
the cross member, filaments and leads to form a unitary
structure.
3. A strain gage -comprising a longitudinally extending
25 cross member, filaments and leads to form a unitary
structure.
5. The combination set forth in claim 2 further char
acterized by the provision of a terminal connected to the
ends of the filament adjacent to the T~shape frame, and
filaments disposed Substantially parallel to said center
lead on opposite sides thereof and connected at one of 30 said terminals being reversely bent over the cross-member
metallic center lead, a cross member secured to one end
of said center lead to form a T-shape frame, a pair of
their ends to said cross member, leads connected to the
other ends of said filaments and disposed adjacent to and
laterally or" the center lead, said cross member being of
«tubular form into Whose ends the iilaments are disposed
and held therein, an insulator tube extending over said
center lead from the cross member to the adjacent por
of the T.
References Cited in the file of this patent
UNITED STATES PATENTS
2,840,675
2,948,872
Giovanni ____________ __ June 24, 1958
Beckman _____________ __ Aug. 9, 1960
Документ
Категория
Без категории
Просмотров
0
Размер файла
330 Кб
Теги
1/--страниц
Пожаловаться на содержимое документа