Signal transmission system for machine tools, inspection machines, and the like

• US 5,150,529 A
• Filed: 04/07/1989
• Issued: 09/29/1992
• Est. Priority Date: 04/12/1988
• Status: Expired due to Term

• Current Assignee: Renishaw PLC Gloucester Street Wotton-Under-Edge Gloucestershire GL12 7DN
• Original Assignee: Renishaw PLC
• Inventors: Collingwood, David
• Primary Examiner(s): Will, Thomas B.
• Application Number:
  US07/334,536
• Time in Patent Office: 1,271 Days
• Field of Search: 33/556-558, 33/559-561, 33/503, 33/832, 340/870.01, 340/870.11, 340/870.12, 340/680, 340/686, 340/825.23, 340/825.58, 340/825.70, 340/825.71, 340/825.72, 340/825.73 , 340/825.74, 340/825.75, 340/825.76, 340/539, 455/603, 455/617, 250/338.1, 250/339, 250/345, 250/349
• US Class Current: 33/503
• CPC Class Codes: G01B 21/047 Accessories, e.g. for positioning, for tool-setting, for measuring probes
• CPC Class Codes: G01B 2210/58 Wireless transmission of information between a sensor or probe and a control or evaluation unit
• CPC Class Codes: G08C 19/12 in which the signal transmitted is frequency or phase of ac
• CPC Class Codes: G08C 2201/40 Remote control systems using repeaters, converters, gateways
• CPC Class Codes: G08C 23/04 using light waves, e.g. infrared
• CPC Class Codes: Y10T 483/17 including machine tool or component

Abstract

Probes (18A,18B,18C) can be interchangably mounted in the spindle (12) of a machine tool. Each probe has an optical signal transmission system, in which an optical signal from a light emitting diode (26) is transmitted to a receiver module 28. Such an arrangement requires a battery in the probe. To conserve battery power, the probe is normally in a stand-by mode, but can be switched on by an optical signal transmitted from the module 28 to a receiving photodiode 32 on the probe. This switch-on signal is modulated at a different frequency for each probe. Each probe contains a filter for the signal received by the photodiode 32, responsive only to the frequency of modulation of its own switch-on signal. Probes which are not intended to be switched on therefore do not react to the switch-on signal of another probe, thus conserving battery power further.

Claims

1. A machine tool signal transmission system comprising:

a plurality of battery-powered wireless sensor signal transmitting means, each having receiving means for receiving a given switch-on signal and means for switching on the battery power upon receipt of that given switch-on signal, and

means remote from the sensor signal transmitting means for generating and transmitting a plurality of given switch-on signals, one given switch-on signal for each sensor signal transmitting means, each given switch-on signal having a unique characteristic for each sensor signal transmitting means,

said receiving means on each sensor signal transmitting means having means responsive to the unique characteristic of the given switch-on signal associated with that sensor signal transmitting means for switching on the battery power in response thereto, but not reacting to other given switch-on signals for other sensor signal transmitting means in said plurality of sensor signal transmitting means.

2. A signal transmission system according to claim 1, wherein the means for transmitting said given signals transmits the signals optically as an optical given signal.

3. A signal transmission system according to claim 2 wherein the unique characteristic is a given color of said optical given signal for each sensor means.

4. A signal transmission system according to claim 1, wherein said signal transmitting means includes means for switching off the battery power.

5. A signal transmission system according to claim 4, wherein said means for switching off comprises timer means for switching off the battery power after a predetermined time has elapsed.

6. A machine tool signal transmission system comprising:

a plurality of battery-powered wireless sensor signal transmitting means, each having receiving means for receiving a given switch-on signal and means for switching on the battery power upon receipt of that given switch-on signal,

means remote from the sensor signal transmitting means for generating and transmitting a plurality of given switch-on signals, one given switch-on signal for each sensor signal transmitting means, each given switch-on signal having a unique characteristic for each sensor signal transmitting means, wherein the unique characteristic is a given frequency of modulation of the given signal for each sensor signal transmitting means,

said receiving means on each sensor signal transmitting means having means responsive to the unique characteristic of the given switch-on signal associated with that sensor signal transmitting means for switching on the battery power in response thereto, but not reacting to other given switch-on signals for other sensor signal transmitting means in said plurality of sensor signal transmitting means.

7. A signal transmission system according to claim 6 wherein said means responsive to the unique characteristic is an electronic filter responsive to said given frequency of modulation.

8. A signal transmission system according to claim 6 wherein said means for generating and transmitting said given signals includes means for enabling a burst of a said given signal in response to receipt of an external signal comprising a burst of a frequency modulated signal.

9. A machine tool signal transmission system comprising:

a plurality of battery-powered wireless sensor signal transmitting means, each having receiving means for receiving a given switch-on signal and means for switching on the battery power upon receipt of that given switch-on signal, and

means remote from the sensor signal transmitting means for generating and transmitting a plurality of given switch-on signals, one given switch-on signal for each sensor signal transmitting means, each given switch-on signal having a unique characteristic for each sensor signal transmitting means,

said receiving means on each sensor signal transmitting means having means responsive to the unique characteristic of the given switch-on signal associated with that sensor signal transmitting means for switching on the battery power in response thereto, but not reacting to other given switch-on signals for other sensor signal transmitting means in said plurality of sensor signal transmitting means, wherein said signal transmitting means includes means for switching off the battery power, and wherein said means for switching off comprises means for receiving a further signal from said means for generating and transmitting said given signals.