Patent · US Expired

Tool force sensor and method of making same

US4741231A · kind A · utility

26Cited by
13References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 14, 1986
Grant dateMay 3, 1988
Priority date
Expiry dateApr 14, 2006

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T82/2549
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A tool force sensor assembly (20) generates an electrical signal which is related to the change in force applied by a tool (24) to a workpiece (28) and is indicative of the wear condition or failure of the tool (24). The sensor assembly (20) is mounted in force transmitting relationship between a movable tool support (30, 36) and a nut member (44, 45) which is driven by screw shaft (40, 41). The sensor assembly (20) comprises a plurality of ring-shaped piezoelectric transducers (48) which are held in preselected, circumferentially spaced relationship to each other around the screw shaft (40, 41) by a retainer ring (56, 58) which is sandwiched between a pair of load distribution plates (52, 54). Fasteners (46) extend through each of the transducers (48) and mount the sensor assembly (20) between the nut member (44, 45) and the tool support (30, 36). An alternate form of the retainer ring (80) is formed by molding the transducers (48 ) within a layer of flexible molding material which allows the transducers (48) to seat properly against the load distribution plates (52, 54). A pair of the sensor assemblies (20) may be respectively mounted on the slide (30) and carriage (36) of a mach…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.