The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 29, 1994
Filed:
Jul. 31, 1992
Daniel M Mills, Riverview, MI (US);
Richard Ogletree, Southfield, MI (US);
Thomas J Lindem, Rockford, IL (US);
Ford Motor Company, Dearborn, MI (US);
Abstract
A multiple-axis machine for positioning a rotary-driven spindle, such positioning being by use of linear motors. The machine has a support for defining multiple axes, with (i) a rigid vibration-dampening bed defining at least an X-axis; (ii) at least one hollow column defining a Y-axis and having one end adjacent and movable along the bed and the other end extending away from said bed; (iii) a slide adapted for movement along the Y-axis of the column; (iv) a cage rigidly fixed to the slide for defining a Z-axis way; and (v) a hollow ram slidable within the cage and along the Z-axis way and carrying the spindle. The machine has bearing assemblies interposed between the column one end and the bed, between the column and slide, and between the cage and ram to provide for respective relative movements along the axes, the bearing assemblies being preloaded to provide an interference fit of 10-20% of the maximum bearing loading. Linear motor assemblies are interposed between the column one end and bed, between the column and slide, and between the cage and ram, the linear motor assemblies are selectably actuatable to impose a linear thrust force upon any or all of the column, slide, or ram for respective movement along the axes. The ratio of the natural frequency of the support and bearing assemblies to the bandwidth of the control velocity loop is slightly greater than one.