Patent AT59505B successfully refreshed from Google Patents.
Patent EP0242747A2 successfully refreshed from Google Patents.
EP0242747A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Probe for measuring workpieces and electrical connections therefor
Assignee: Renishaw PLC
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Filing: 1987-04-11
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Granted: —
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Expires: 2007-04-11
Abstract
Abstract The invention enables two-way communication to be established between a measuring probe on a machine spindle and the machine using only two wires between the probe and the machine. Communication from the probe to the machine is achieved by causing current changes in an electrical circuit within the probe (due to the probe circuit changing state when a workpiece is detected) to be sensed by a current sensing circuit on the machine to produce an output in the machine circuit indicative of workpiece detection. Communication from the machine to the probe is achieved by varying the voltage supplied to the probe circuit under the control of the machine controller, the change in voltage being sensed by components of the probe circuit to initiate different functions of the probe circuit e.g. re-setting the probe or changing the gain of a component.
Inventors
- 👤 Clifford William Archer
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-05 08:19
CPC Classifications
G; G01; G01B; G01B7/00; G01B7/002; G01B7/004; G01B7/008; G01B7/012
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
126 words
Measuring apparatus including a measuring probe for determining the co-ordinate position of the probe relative to a workpiece, the apparatus including an internal electrical circuit within the probe, an electrical circuit external to the probe, a power supply for the circuits and electrical connections between the circuits,characterised in that a first one of the circuits includes means responsive to a change in voltage initiated by the other of the circuits to produce an output for use within said first circuit, the other one of the two circuits includes means responsive to a change in current initiated by the first one of the two circuits to produce and output, for use within said other circuit whereby only two electrical connections between the two electrical circuits are necessary.
Claim 2
Dependent Claim
126 words
Measuring apparatus including a measuring probe for determining the co-ordinate position of the probe relative to a workpiece, the apparatus including an internal electrical circuit within the probe, an electrical circuit external to the probe, a power supply for the circuits and electrical connections between the circuits,characterised in that a first one of the circuits includes means responsive to a change in voltage initiated by the other of the circuits to produce an output for use within said first circuit, the other one of the two circuits includes means responsive to a change in current initiated by the first one of the two circuits to produce and output, for use within said other circuit whereby only two electrical connections between the two electrical circuits are necessary.
Claim 3
Dependent Claim
44 words
Measuring apparatus as claimed in claim 1 characterised in that the power supply comprises a DC supply in the external circuit, and the external circuit includes switch means whereby the voltage output of the external circuit is switchable between a plurality of different levels.
Claim 4
Dependent Claim
30 words
Measuring apparatus as claimed in claim 2 characterised in that the machine includes a control system and the switch means are operated under the control of the machine control system.
Claim 5
Dependent Claim
41 words
Measuring apparatus as claimed in claim 2 characterised in that the internal circuit includes components activated in accordance with the voltage applied thereto from the external circuit to control the functions of other components within the internal circuit of the probe.
Claim 6
Dependent Claim
57 words
Measuring apparatus as claimed in claim 1 characterised in that the internal circuit includes means for changing the current flowing therein when the probe contacts the workpiece and the external circuit includes a current sensing means which senses the change in current and produces an output signal which is passed to a control system of the machine.
Claim 7
Dependent Claim
102 words
Measuring apparatus as claimed in claim 5 and characterised in that the probe comprises a fixed part for attachment to the machine and a movable part supported in a rest position on the fixed part and which is displaceable therefrom against the action of bias means when the probe engages the workpiece, characterised in that the internal and external circuits combine to produce a first quiescent current level at a first predetermined voltage from the power supply when the probe is in said rest position, and to provide a second current level when the movable part is displaced from the rest position.
References Cited (Backward Citations)
No citation records indexed.
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