Year: 1897

page_text: Date of Application, 30th Dec., 1897-Accepted, 26th Feb., 1898
Fig. 3 is a cross section taken on the line B-B Fig. 1.
Fig. 4 is a longitudinal section.
Fig. 5 is a front view.
In Figs. 2 to 5 the mandrel is removed.
Referring to the drawings whereon the same reference letters wherever repeated
indicate the same parts.
a is the usual tapered mandrel for expanding the rollers of which there are two
sets b, c. d is the body which is reduced, as shown, at the end and also at the
end 72. e, el, e² are sliding carriers which can move in radial slots f, f¹, f cut
in the part of the body. Fitted loosely in recesses 61 in these carriers are the
rollers b. As usual the rollers b are prevented from coming out of the carriers on
the outside by the tapered or reduced lips of the recesses b₁ as clearly shown at
Fig. 2 and they are prevented from falling out of place on the inside, when the
mandrel is withdrawn, by the screws g.
As will be seen, each carrier is made of an oblong shape with a nose piece e
and a tail piece 5. The tail pieces e slide in slots f³ of a corresponding shape cut
in the central part d of the body. The carriers which are larger than the central
hole of the body cannot, as a consequence, come out of place at the inside and in
order to prevent them coming out of place at the outside plates hare dovetailed
into the body part d. Fitted in the tail parts e5 of the carriers and bearing against
the undersides of the plates h are spiral springs which tend to force the carriers
inwards.
The large rollers c are prevented from coming out of their recesses c¹ cut in the
body d by the reduced lips at the outside and they are prevented from coming.
out of place on the inside by the tail pieces es of the carriers as clearly shown at
Fig. 3.
is a loose cape having two long projections 1 and two short projections *.
The object of this cape is as in ordinary expanders, to prevent the expander going
further than a given point into the tube. The end with the long projections ¹ is
used when the tubes are being expanded by the rollers 6 and the short projections
when the tubes are being expanded by the rollers c.
The cape which can be taken off and reversed when necessary is held in place
037

page_text: by a washer k secured to the body part & by a set pin or a pin through the washer.
and body as at 7.
As will be seen both the carriers e, e¹, e² with their rollers b and the rollers c are
arranged at a slight angle to the axial line of the body. This is for the purpose of
giving a screw action so as to make the expander self feeding.
If desired, the body part may also be fitted with carriers for the rollers c.
In Fig. 1 the tapered mandrel a is shown as inserted its full length into the
body so that the rollers are expanded or forced out. In Figs. 2 and 3 the rollers
are shown in their in or unexpanded positions.
The action of the device is as follows:
The body of the expander is inserted into the tube with the projection's j¹ of the
cape bearing against the tube plate, the tapered mandrel is then pushed into
its place until the rollers b press hard against the inside surface of the tube. The
mandrel is now turned to the right and owing to the screw action of the rollers it
is drawn inwards and therefore self-expands the tube.
By turning the mandrel to the left the rollers become released.
When the rollers c are to be used the cape is turned round so that its projec-
tions bear against the tube plate.
The benefits of this expander over ordinary expanders are that whereas ordinary
expanders will usually expand one size of tube only this expander will expand five
or more sizes of tubes the one shown being capable of doing seven sizes. While
it can do so many different sizes it is constructed so that no part of the carriers is
unsupported, being supported all round by the body and is therefore of a stronger
construction than other expanders with a similar object.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed we declare that what
we consider novel and desire to claim is: -
1. The construction or general arrangement and combination of parts of the tube
expander, substantially as hereinbefore described with reference to the drawings
annexed.
2. In a tube expander sliding carriers e for the rollers made substantially as
herein before described and shown on the drawings annexed.
Dated this 29th day of December 1807
H. D. FITZPATRICK,
70, Wellington Street, Glasgow, Agent.