Drafting machine

Claim 2

A drafting machine, comprising a rectangular drafting frame, a continuous and uninterrupted guide groove provided on a drawing surface of said frame and having portions parallel to each side edge thereof, said groove having smooth outer and inner side walls and making a smooth transition at corners of said frame by having smooth rounded corners thereat, a pair of spaced apart slide elements disposed in said groove, bridge means interconnecting said slide elements, at least one drawing instrument being connected to said bridge means, and said slide elements each having a rounded surface facing inwardly of said frame, whereby said instrument may be displaced longitudinally of said guide groove in a rectilinear movement along said portions thereof, and whereby said instrument pivots about a central axis of said bridge means located between said slide elements upon movement of said instrument along said rounded corners.

Claim 3

The machine according to claim 1, wherein said drawing instrument has a single elongated slot defining four edges together with the side edges of said drawing instrument, graduated scales being disposed on each of said edges.

Claim 4

A drafting machine, comprising a rectangular drafting frame, a continuous and uninterrupted guide groove provided on a drawing surface of said frame and having portions parallel to each side edge thereof, said groove having smooth outer and inner side walls and making a smooth transition at corners of said frame by having smooth rounded corners thereat, at least one slide element disposed in said groove, said slide element having a flat plane surface and an opposite domed surface respectively in smooth contacting engagement with said outer and said inner walls of said groove, at least one drawing instrument being connected to said slide element, whereby said instrument may be displaced longitudinally of said guide groove in a rectilinear movement along said portions thereof, and whereby said instrument pivots about a central axis of said slide element upon movement of said instrument along said rounded corners.

Claim 5

A drafting machine, comprising a rectangular drafting frame, a continuous and uninterrupted guide groove provided on a drawing surface of said frame and having portions parallel to each side edge thereof, said groove having smooth outer and inner side walls and making a smooth transition at corners of said frame by having smooth rounded corners thereat, at least one slide element disposed in said groove, said slide element having a flat plane surface and an opposite domed surface respectively in smooth contacting engagement with said outer and said inner walls of said groove, at least one drawing instrument being connected to said slide element, whereby said instrument may be displaced longitudinally of said guide groove in a rectilinear movement along said portions thereof, and whereby said instrument pivots about a central axis of said slide element upon movement of said instrument along said rounded corners.

Claim 6

The machine according to claim 3, wherein a protractor having an annular scale thereon is rotatably mounted on said slide element.

Claim 7

The machine according to claim 4, wherein a circular disc is rotatably mounted on said slide element, said disc having an indicator mark and further having a stop element thereon over which said drawing instrument extends for guiding same relative to said groove.

Claim 8

The machine according to claim 5, wherein an arrestor device is provided between said disc and said protractor for retaining said disc in a fixed angular position relative to said protractor.

Claim 9

The machine according to claim 5, wherein said stop element has at least two bearing surfaces thereon.

Claim 10

The machine according to claim 4, wherein said drawing surface has a depression thereon parallel to said groove, said depression having opposite flat sidewalls, and said protractor being disposed within said depression and having opposite flat sidewalls for guiding said protractor along said depression side walls.

Claim 11

The machine according to claim 3, wherein a knob is provided for connecting said drawing instrument to said slide element, said drawing instrument being slideable relative to said slide element.

Claim 12

A drafting machine, comprising a rectangular drafting frame, a continuous and uninterrupted guide groove provided on a drawing surface of said frame along each side edge thereof, a slide element slideably disposed in said groove, a drawing instrument pivotably connected to said slide element, a disc rotatably mounted on said slide element, said disc having a stop element thereon, and said drawing instrument having an opening therein snugly embracing said stop element, whereby said drawing instrument may be slid longitudinally of said groove and rotated angularly relative thereto.

Claim 13

A drafting machine, comprising a rectangular drafting frame, a continuous and uninterrupted guide groove provided on a drawing surface of said frame along each side edge thereof, a slide element slideably disposed in said groove, a drawing instrument pivotably connected to said slide element, a disc rotatably mounted on said slide element, said disc having a stop element thereon, and said drawing instrument having an opening therein snugly embracing said stop element, whereby said drawing instrument may be slid longitudinally of said groove and rotated angularly relative thereto.

Claim 14

A drafting machine, comprising a rectangular drafting frame, a continuous and uninterrupted guide groove provided on a drawing surface of said frame and having portions parallel to each side edge thereof, said groove having smooth outer and inner side walls and making a smooth transition at corners of said frame by having smooth rounded corners thereat, at least one slide element disposed in said groove, said slide element being elongated and bearing against said side walls of said groove at spaced bearing points on said slide element, at least one drawing instrument being connected to said slide element, and said slide element having a rounded surface facing inwardly of said frame, whereby said instrument may be displaced longitudinally of said guide groove in a rectilinear movement along said portions thereof, and whereby said instrument pivots about a central axis of said slide element upon movement of said instrument along said rounded corners.

Claim 15

A drafting machine, comprising a rectangular drafting frame, a continuous and uninterrupted guide groove provided on a drawing surface of said frame and having portions parallel to each side edge thereof, said groove having smooth outer and inner side walls and making a smooth transition at corners of said frame by having smooth rounded corners thereat, at least one slide element disposed in said groove, said slide element being elongated and bearing against said side walls of said groove at spaced bearing points on said slide element, at least one drawing instrument being connected to said slide element, and said slide element having a rounded surface facing inwardly of said frame, whereby said instrument may be displaced longitudinally of said guide groove in a rectilinear movement along said portions thereof, and whereby said instrument pivots about a central axis of said slide element upon movement of said instrument along said rounded corners.

Claim 16

A drafting machine, comprising a rectangular drafting frame, a continuous and uninterrupted guide groove provided on a drawing surface of said frame and having portions parallel to each side edge thereof, said groove having smooth outer and inner side walls and making a smooth transition at corners of said frame by having smooth rounded corners thereat, at least one slide element of magnetic material being disposed in said groove, and a magnetized rod being disposed within said groove for attracting said slide element and retaining it within said groove, at least one drawing instrument being connected to said slide element, and said slide element having a rounded surface facing inwardly of said frame, whereby said instrument may be displaced longitudinally of said guide groove in a rectilinear movement along said portions thereof, and whereby said instrument pivots about a central axis of said slide element upon movement of said instrument along said rounded corners.

Claim 17

A drafting machine, comprising a rectangular drafting frame, a continuous and uninterrupted guide groove provided on a drawing surface of said frame and having portions parallel to each side edge thereof, said groove having smooth outer and inner side walls and making a smooth transition at corners of said frame by having smooth rounded corners thereat, at least one slide element of magnetic material being disposed in said groove, and a magnetized rod being disposed within said groove for attracting said slide element and retaining it within said groove, at least one drawing instrument being connected to said slide element, and said slide element having a rounded surface facing inwardly of said frame, whereby said instrument may be displaced longitudinally of said guide groove in a rectilinear movement along said portions thereof, and whereby said instrument pivots about a central axis of said slide element upon movement of said instrument along said rounded corners.

Claim 18

A drafting machine, comprising a rectangular drafting frame, a continuous and uninterrupted guide groove provided on a drawing surface of said frame and having portions parallel to each side edge thereof, said groove having smooth outer and inner side walls and making a smooth transition at corners of said frame by having smooth rounded corners thereat, at least one slide element disposed in said groove, at least one drawing instrument being connected to said slide element, a protractor being fixedly mounted over said slide element by means of bearings engaging a side edge of said drafting frame, and said slide element having a rounded surface facing inwardly of said frame, whereby said instrument may be displaced longitudinally of said guide groove in a rectilinear movement along said portions thereof, and whereby said instrument pivots about a central axis of said slide element upon movement of said instrument along said rounded corners.

Claim 19

A drafting machine, comprising a rectangular drafting frame, a continuous and uninterrupted guide groove provided on a drawing surface of said frame and having portions parallel to each side edge thereof, said groove having smooth outer and inner side walls and making a smooth transition at corners of said frame by having smooth rounded corners thereat, at least one slide element disposed in said groove, at least one drawing instrument being connected to said slide element, a protractor being fixedly mounted over said slide element by means of bearings engaging a side edge of said drafting frame, and said slide element having a rounded surface facing inwardly of said frame, whereby said instrument may be displaced longitudinally of said guide groove in a rectilinear movement along said portions thereof, and whereby said instrument pivots about a central axis of said slide element upon movement of said instrument along said rounded corners.