IMPROVEMENTS IN APPARATUS FOR TESTING THE STRENGTH OF CEMENT AND OTHER SUBSTANCES to be as follows:
Year: 1884

page_text: PROVISIONAL SPECIFICATION.
I, HENRY FAIJA, of 4 Great Queen Street, Westminster, in the County of
Middlesex, Civil Engineer, do hereby declare the nature of said invention for
"IMPROVEMENTS IN APPARATUS FOR TESTING THE STRENGTH OF CEMENT AND
OTHER SUBSTANCES to be as follows:—
"
:
My invention has for object to produce a simple compact and efficient machine
whereby the strength of cement and various other solid substances may be readily
tested. In a machine according to my invention for such purposes the lever
through which the strain is exerted upon the material to be tested is worked
through a spring balance that indicates the strain.
'
Such a machine according to one arrangement comprises a base plate with a
suitable standard or frame that carries a lever or steel yard having a balance weight
at its shorter end to balance the longer arm and parts connected thereto. To this
end is connected one of the clips for holding a briquette or piece of material to be
tested, a second clip is secured to a projection or bracket by adjustable means such
as a screwed bolt. with nut-The longer arm of the lever is connected to a spring
balance with indicator which in turn is connected to a band or chain that passes
around a pulley, or drum on the same axis as a spur wheel (it may have inclined
teeth) or worm wheel which is driven by a pinion or worm operated by a crank
handle.
.
A bifurcated bracket with spring cushion is provided to guide and. arrest the
descent of the longer arm of the lever when the piece of material under test
breaks.
It will be evident that with this arrangement the spring balance will indicate
the breaking strain of the briquette or piece of cement or other material tested.

page_text: COMPLETE SPECIFICATION.
I, HENRY FAIJA of 4 Great Queen Street, Westminster, in the County of
Middlesex, Civil Engineer, do hereby declare the nature of my invention for
"IMPROVEMENTS IN APPARATUS FOR TESTING THE STRENGTH OF CEMENT AND
OTHER SUBSTANCES," and in what manner the same is to be performed, to be
particularly described and ascertained in and by the following statement:-
My invention has for object to produce a simple compact and efficient machine
whereby the strength of cement and various other solid substances may be readily
tested. In a machine according to my invention for such purposes the steel yard
or lever through which the strain is exerted upon the material to be tested is
worked through a spring balance that indicates the strain. The gear for actuating
the steel yard or lever through the spring balance is so contrived that the operating
handle can be readily thrown out of gear so as to enable the spring balance
indicator to be rapidly returned to zero. A, recoil spring or springs is or are
provided for receiving the shock due to the sudden release of the steel yard or lever
and recoil of the spring balance on breakage of a piece of material tested.
Referring to the accompanying sheet of drawings, Fig 1 represents in side
elevation and Fig 2 in end elevation a machine embodying my improvements.
a is an upright or standard on which the steel yard rests and which has
a projection b that carries the lower clip. It has also a projecting arm c on the
end of which a recoil spring d is fixed. The two clips e, e which hold the test
piece are respectively fixed, the upper one to the steel yard k, by means of double
links f hanging on a knife edge and the lower one by means of the link g which
fits loosely in a square hole in band which is screwed on the end to receive the
nut wheel h. The wheel h works against the lower side of b and the arrangement
allows of the adjustment of the distance apart of the clips to suit the test piece j.
The steel yard k has at one end a balance weight m and at the other on the knife
edge n is hung the spring balance o. By means of a chain or rope p the spring
balance is attached to a drum part wheel or segment q. These work on a centre or
axle in the uprights r. r, which are fixed to the standard a. The segment q is actuated
by the worm 8. The strain may be conveniently put on the test piece by turning
this worm, or the power required to apply the strain and the speed at which the
strain is applied may be reduced by the combination of the wheel and pinion t
and u the handle w being on the same spindle as the pinion u. When this gearing
is adopted I make the spindle y on which the pinion u is keyed to slide in its
journals so that the pinion u may be put out of gear with the wheel t by pushing the
spring or equivalent stop piece on one side. The object of this is that whereas
the strain may be put upon the test piece slowly the balance indicator can on the
other hand be returned to zero quickly by throwing the pinion out of gear and
turning wheel t by handle cc.
The action of the machine is as follows:-
The handle w is turned until the segment q is in the position shewn in Fig 1,
ן.
20

page_text: edges i the wheel his screwed down the thread so that the clips e. e may be brought
together and the piece to be tested ; put in between the jaws of the clips e. e. The
link g bringing with it the lower clip is then brought down by screwing the wheel h
against b until the steel yard k is level. The handle w is then turned and the spring
balance gradually pulled down until the strain tears the test piece asunder. The
loose pointer shows on the dial of the balance the strain at which the test piece
broke; immediately the test piece is broken the end of steel yard k carrying the
spring balance falls, and is caught by the projecting ends of the knife edges n
resting on the spring d.
The drawings show a machine with clips arranged to test cement, and the test
piece is an ordinary cement test piece or briquette of 1" section. The spring
balance is tested and scaled up to 100 lbs and the proportion of the steel yard k is
as 10 to 1, so that the ultimate strain possible is 1000 lbs, but it is evident that
with differently arranged clips the machine can be arranged to test the strength of
any material, and that by adopting another balance or different proportion of
leverage in the steel yard k much greater or more delicate strains can be dealt
with.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is
1. In a machine for testing the strength of cement and other substances the
combination with a steel yard or lever through which the strain is to be exerted
upon material to be tested of a spring balance and means for operating the steel
yard or lever through such spring balance so that the latter shall indicate the
breaking strain of the material tested substantially as described.
2. In a machine for testing the strength of cement and other substances the
combination of a steel yard or lever through which the strain is to be exerted upon
material to be tested, a spring balance, means for operating said steel yard or lever
through said spring balance, and a recoil spring (or springs) for receiving the shock
due to the sudden release of the steel yard or lever and recoil of the spring balance
on breakage of a piece of material tested substantially as described.
3. The machine for testing the strength of cement and other substances constructed
arranged and operating as shewn in the drawings and described with reference
thereto.
00
3000