US2431346A - Layout tool - Google Patents

Description

Nov. 25, 1947. TESCANUN 2,431,346

Filed Aug. 11, 1945 I THOMAS E SCANLIN grwa/Mxw v Patented Nov. 25, 1947 UNITED STATES PATENT OFFICE (Granted under the act of March 3, 1883, as amended April 30, 1928:; 370- 0. G. 7:):

2 Claims.

This invention relates to layout instruments for marking the proper cuts to be made in a shipor other structure in which shaft tubes or other cylinders are to be installed.

More particularly this invention is directed to a longitudinal member, such as a small pipe, mounted on a series of supports in a manner so that the center line of the pipe corresponds to the center line of the larger tube or cylinder to be installed. An adjustable scriber attached to the pipe as by a slip fitting T may be moved along the pipe and revolved about it. It will mark the desired straight or curved lines and arcs of circles on all intersecting surfaces on which a cut is to be made. The scriber, depending on the use to which it is to be put, will be straight or hooked at its end. It is adjustable and so can be made to equal the radius of the cylinder for which the markings are being made. A screw threaded sleeve may receive the hooked scriber end or it may be made in one piece.

The supports preferably comprise a number of perforated target plates slotted for ingress and egress of an aligning center line wire. The target plates are tack welded to braces after which the centerline wire is removed and the small pipe inserted through the aligned perforations.

Prior to these improvements, the practice was to cut the ships or other structure to a greater extent than required and then to use collars to close the out after installation of the cylinder. This practice requires considerable judgement and is expensive and wasteful in time and labor and where clearances are small is highly unsatisfactory.

As will be apparent from the description and drawing, the hooked scriber will be used for marking closed curves such as are formed by a cylinder when its center line intersects the deck at an angle greater .than 45 and for marking arcs on surfaces which form an angle greater than 45 with the-center line of the cylinder. The straight scriber will be used principally for straight lines and curves generated by cylinders whose center lines intersect the deck at angles less than 45.

The small pipe mentioned above will constitute a longitudinal pivot means so supported that its centerline will correspond with the centerline of the cylinder after installation. It will be understood that the term centerline as used in the claims includes the extension of the actual centerline of the installation.

It will be seen that the device will make accurate cutting marks on irregular surfaces as well as on a plurality of surfaces which are to be intersected by the installation.

An object of these improvements is to provide a simple yet efiicient instrument for marking cutting lines for the installation of a cylindrical unit.

Another object is to provide a longitudinallymoveable and rotatable marking device for movement longitudinally of and rotationally about centers corresponding to the center line of a unit l after installation.

Another object is to provide a pipe with a ion gitudinally moveable and rotatably mounted scriber, and aligned supports for the pipe.

Another object is to provide an improved method of marking portions of a structure for cutting.

These and other objects of invention will be manifest from a. consideration of the following description, claims and drawings in which:

Fig. I is a slightly distorted assembly view of my marking instrument in conjunction with acut-out portion of a structurepreviously cut along the markings made.

Fig. 2 is adetail assembly of the pipe, a pipe support. and scriber.

Fig. 3 is a detail view: of a target plate and centerline wire used in the erection of the improved device.

Referring to the drawing, Fig. 1 shows a surface such as a ships deck I0 having a cut-out portion I l to receive a shaft or cylinder (not shown). Deck supporting plates I2, I 3 and M with concave ends l5, l6 and I! provide supports for the installation. Both the deck and deck supportin plates present a structure resulting from cutting along the marks produced by the improved device. The cutting may be exactly to size and hence the collars previously used are dispensed with.

My improved device and its operation will be understood from its method of erection and the following description:

A centerline wire 20 is conveniently erected, drawn taut, and secured so as to be along the centerline of the shaft or cylinder when it is in installed position. Two or more perforated target plates 2| are slotted as at 22 to permit them to be centered by the wire 20. This centering may be done by the use of braces 23 and clamp 24 after which the legs may be tack welded as at 25 and 2B. The present improvements contemplate various forms of supports, the illustrated embodiment being preferred for long and relatively narrow marking requirements. When the supports are erected the wire 20 may be removed and a length of 1 /1 pipe 21 inserted as shown in Fig.

1. A T connection 28 engages the pipe by a sliding line of the pipe 21 will mark surfaces forming an obtuse angle with the plane of the centerline as shown in Fig. 1. It will be understood that the pipe may carry one or a plurality of scribers and is removable from the legs or braces 23. In both the straight end marker 39 and the hooked marker 32 the marking point is spaced from the centerline a distance equal to the radius of the shaft or cylinder to be installed. When the.

straight end marker 39' is moved along the pipe 27 it will scribe a line or mark along which the wall of an intersecting cylinder will cut the deck or surface. 7

In Fig. 1 three supportsAll, 4| and 42 are shown. To mark the portion between supports 46 and M, all that is necessary is to remove the pipe 21 'and transfer the straight end scriber so that it is moveable between these two supports. At the point the cylinder first will intersect the deck'a point contact is made which gradually widens out as the marker moves longitudinally and is caused to revolve by the deck or floor.

The pipe 27 will be on any convenient length but I have found that lengths of 12 foot 1 inch pipe is sufiicient for most installations aboard ship.

The hooked scriber 32 likewise moves longitudinally and rotatably if necessary to describe cutting arcs on supporting plates l2, l3 and i4.

Having described my invention in a preferred embodiment, I desire to be limited only by the scope of the appended claims.

This invention may be made or used by or for the Government of the United States for govern- What I claim is:

1. The method of setting up a supporting tubular railfor the longitudinally slidable pivot of a scriber of a layout tool comprising setting up a taut wire at the longitudinal center line of a cylindrical object which is to be installed partly through an obstructing surface, securing a plurality of legs to the obstructing surface at an angle normal to the taut wire, securing an apertured slotted rail supporting plate to each leg by sliding the slot in the plate about the taut wire to place the plate with the center of the aperture coinciding with the taut wire and affixing the plate to a leg, then removing the taut wire and V positioning the rail through the series of apertures with a scriber pivot between each successive pair of plates.

2. A layout tool comprising a plurality of V legs arranged to be secured to an obstructing any royalties thereon or therefor.

surface through which a cylindrical object is to be installed, an apertured plate arranged to be;

REFERENCES CITED The following references are of record in the file of this patent: V

UNITED STATES PATENTS Number 7 Name Date 1,660,616 James Feb. 28, 1923 1,991,117 Porteous et a1. Feb. 12, 1935 FOREIGN PATENTS Number Country Date 374,102 France Sept; 24, 1904

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