IMPROVEMENTS IN PARALLEL VICES
Year: 1882

page_text: LETTERS PATENT to William Maxwell MacBrair of Sheaf Island Works
Sheffield in the County of York Vice & Engineer's Tool Manufacturer for an
PROVISIONAL SPECIFICATION left by the said William Maxwell MacBrair
at the Office of the Commissioners of Patents on the 12th August 1882.
WILLIAM MAXWELL MACBRAIR of Sheaf Island Works Sheffield in the County
of York Vice & Engineer's Tool Manufacturer IMPROVEMENTS IN PARALLEL VICES
My Invention relates to the class of Bench Vices having parallel action in
movement, and has for its object to simplify and improve the construction, to reduce
the cost and to render them available to a greater extent than at present-In
construction I proceed as follows-I cast the Heads or Jaws in Steel or any of the
varieties of cast iron, & the forged gripping faces (made of steel) I either weld or
attach by screws or pour the molten metal upon & so cause them to adhere firmly-
To the front or moving Jaw I fix firmly a sliding bar of maleable iron of any
convenient section or shape
I also shape the Jaws so as to receive a Box having a screw thread formed or
fixed internally at its further end, leaving the front part free from strain & acting
as a cover to the Screw which is attached to the front or Moving Jaw; the whole
vice being arranged & constructed to distribute the strain over the several parts.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said William Maxwell MacBrair in the Great Seal Patent Office on
the 8th February 1883.
WILLIAM MAXWELL MACBRAIR of Sheaf Island Works Sheffield in the County
IMPROVEMENTS IN PARALLEL
of York Vice and Engineers Tool Manufacturer
VICES
My Invention relates to the class of Bench Vices having parellel Action in
movement and has for its object to simplify and improve the construction to reduce
the cost and to render them available to a greater extent than at present In
construction I proceed as follows: I cast the Heads or Jaws in steel or any of the
varieties of cast metal and the forged gripping steel faces I either weld on attach
by screws or pour the molten metal upon and so cause them to adhere firmly. To
the front or moving Jaw I fix firmly a sliding bar of maleable iron of any
convenient section or shape. I also shape the Jaws so as to receive a solid Box
having a screw thread formed or fixed internally at its further end leaving the
front part free from strain and acting as a cover to the screw which is attached to
the front or moving Jaw-The whole vice being arranged and constructed to
distribute the strain over the several parts-And in order that my said Invention
may be properly understood I now proceed more particularly to setforth the mode
or manner in which the saine is or may be used or practically carried into effect,
reference being had to the accompanying sheet of drawings and to the letters and
figures marked thereon: that is to say:-
Fig 1 is a side Elevation (of a Vice constructed according to this Invention)
Fig 2 is a Back Elevation (of the same) Fig 3 is a Front Elevation-Fig 4 is.
a Plan view Fig 5 is a Transverse Section on the line A B of Fig 4-Like Letters
indicate like parts in all the figures
A is the front or moveable Head of the Vice having the gripping steel Jaw J
secured thereto in one of the Modes specified. The front part is made to project
and cover the collar of the Screw C and in the cavity so formed a Steel Spring
Washer S is introduced to maintain a close contact of the said Collar with the screw
pin F for opening the Vice-And the lower part of the said Head is formed with a
hole in which the bar D is securely fitted and attached-A1 is the Back or fixed
Head and carries a similar steel gripping Jaw J corresponding to that on A while
the lower portion of Head is extended backwards the full length of the base
plate E securing a firm attachment and forming a box in which the Bar D moves
freely. The Box B is secured to the Back Jaw and is formed with a solid collar,
screw threads are formed or fixed internally extending from the front of the said
collar to near the hinder end of box, the front portion being left plain of larger
diameter to act as cover to the Screw when Vice is in use the whole of the moving
parts being thus protected from the easy admission of filings and dirt which usually
prove so detrimental to vices of the Ordinary Construction
Having now described and ascertained the nature of my Invention and shewn
how the same may be carried into practical effect, I would have it understood that
I do not confine myself to the precise details as herein illustrated as these details
may be varied without departing from the spirit of my Invention
But what I claim and desire to secure by Letters Patent is
1st The formation substantially as specified of Vice Heads in Cast Metal having
the steel gripping Jaws attached thereto in the molten state or afterwards by
welding or screws.

page_text: 2nd The construction and arrangement of the Screw, Screw Box and steel
spring washer substantially as specified and for the purposes setforth
In witness whereof I the said William Maxwell MacBrair have hereunto set
my hand and seal this Seventh day of February One thousand eight
hundred and eighty three
WILLIAM MAXWELL (L.S.) MACBRAIR