GB2290622A - Radiant wave energy-coupled test meter - Google Patents

Abstract

A sensing probe assembly is provided for an electrical test meter of the type having microprocessor 1300 responsive to electrical signals for changing various aspects of the test meter display 1700 and operating mode functions. It comprises a first universally movable sensing probe 16 having a probe housing; a wave energy signal transmitter 1650 mounted on said probe housing; power supply coupling means 1604 mounted on said probe housing and electrically coupled to the wave energy signal transmitter 1650 for coupling a source of electrical energy thereto and a sensor 18 mounted to said probe housing for sensing a parameter of an external object. The sensor 18 is electrically connected to the wave energy signal transmitter 1650 for delivering thereto an electrical signal representative of a sensed value of the said parameter. The wave energy signal transmitter 1650 is electrically coupled to the power supply coupling means 1604 for transmitting externally of the probe housing in wave energy form, a signal representative of a sensed value of the said parameter, for receipt by a test meter unit 1000 having a wave energy receiver 1200 associated therewith. <IMAGE>

Description

RADIANT WAVEENERGY-COUPLED TEST METER HELD OF THE INVENTION This invention relates generally to test meter assemblies of the type having a hand held probe for sensing one or more parameters, and a meter unit capable of producing displays indicative of values of the sensed parameters for the benefit of a human operator. The displays may be audible or visual or both, at the operator's choice. More particularly, this invention relates to a test meter assembly of the type described, in which the probe is not directly coupled to the meter unit by an electrically conductive wire or cable, and data representative of the values of sensed parameters are delivered from the probe to the meter unit via wave energy such as light waves or radio waves.

This invention further relates to a means for improving the safety and convenience of test meters such as multimeters and pyrometers that incorporate voice enunciation in that there are no metallic conductors or connecting means between the test points and the test meter when it is desired to actuate the voice function.

Test meter assemblies having movable hand-held sensing probes are well-known and widely used in the fields of manufacturing, electronic trouble-shooting, research, development and the like. In the prior art, such meters have been consistently "tethered" or directly coupled to the movable probe by means of an electrically conductive wire or cable that provides an electrical coupling path from the sensors in the probe to the electronic circuits in the meter unit. Such a test meter assembly is clearly described and fully disclosed in United States Patent No. 4,949,274, issued August 4, 1990 and assigned to the assignee of this application. The specification and drawings of said patent will be referred to herein and they are, accordingly, incorporated by reference into this application.

The prior art practice of coupling a meter unit to a test/sensing probe by means of electrically conductive wires or cables unavoidably involves various considerations that directly or indirectly affect the safety and convenience of use of such test meter assemblies. Safety considerations include the possibility that an electrically conductive path between the probe and the meter unit may come into contact unintentionally with a source of electrical energy that might injure the operator or damage or destroy either the meter unit or the probe or both.The same conductive path can affect convenience of use of the assembly by imposing the need to assure that the conductor does not come into contact with any unintended source of energy, in addition to requiring assurance that the position of the conductor relative to other electrical equipment does not subject it to unintended magnetically-induced electrical current flow.

Accordingly, the invention seeks to provide a test meter assembly that does not expose an operator to the danger of unintended electrical current flow or applied voltage between the probe and meter unit.

The invention also seeks to provide a test meter assembly that is not subject to the possibility of stray electro-magnetic signal creation/transmission between the probe and the meter unit.

Still further, the invention seeks to provide a test meter assembly that delivers signals from the sensing probe to the meter unit via a non-conductive path.

According to the invention, there is provided a sensing probe assembly, for an electrical test meter of the type having a microprocessor responsive to electrical signals for changing various aspects of the test meter display and operating mode functions, said probe assembly comprising a first universally movable sensing probe having a probe housing; a wave energy signal transmitter mounted on said probe housing; first power supply coupling means mounted on said probe housing and electrically coupled to said wave energy signal transmitter for coupling a source of electrical energy thereto; a first sensor mounted to said probe housing for sensing a parameter of an external object; said sensor being electrically connected to said wave energy signal transmitter for delivering thereto an electrical signal representative of a sensed value of said parameter; said wave energy signal transmitter being electrically coupled to the said first power supply coupling means for transmitting externally of said probe housing in wave energy form, a signal representative of a sensed value of said parameter, for receipt by a test meter unit having a wave energy receiver associated therewith.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described in greater detail by way of example, with reference to the drawings in which Figure 1 is a partial block diagram of a test meter assembly showing the arrangement of circuit components for a preferred embodiment of this invention; Figure 2 is a side elevation view of a universally movable sensing probe in accordance with this invention; Figure 3 is a side elevation view of a detachable handle/plug subassembly for selectively coupling an external electrical supply to the probe of Figure 2, in accordance with this invention; Figure 4 is a side elevation view of a probe having an infrared transmitter and an infrared signal receiver associated with the test meter in accordance with this invention;; Figure 5 is a side elevation view of a probe having an optical fibre signal transmitter coupled by means of a length of optical fibre cable to an optical fibre signal receiver associated with a test meter in accordance with this invention; Figure 6 is a top plan view of a pair of coupled-together sensing probes useable in accordance with this invention; Figure 7 is a side elevation view of a probe having an acoustic transmitter and an acoustic signal receiver associated with the test meter in accordance with this invention; and Figure 8 is a top plan view of a probe having an electromagnetic signal transmitter located generally within a coil of electromagnetic wire for inducing signals therein in accordance with this invention.

DETAILED DESCRIPTION OF THE INVENTION The embodiment of the invention illustrated in part by the block diagram of Figure 1, herein, considered with reference to the drawings and the specification of U.S. Patent No.

4,949,247 (hereinafter referred to as : '247), will be seen to comprise a universally movable sensing probe 16 incorporating a radio frequency transmitting antenna 1600 together with a radio frequency transmitter 1650, and a meter unit 1000 incorporating a radio frequency receiver 1200, and a receiving antenna 1610 for receiving conventional radio wave signals from transmitting antenna 1600. The signals transmitted from antenna 1600 represent either control signals or values of parameters sensed by probe 16 in the manner disclosed in '274. Control signals or information about the sensed values may be transmitted in any conventional signal form such as analog or digital coded signals.

The choice of signal form requires only that suitable corresponding receiving components are associated with the radio frequency receiver 1200, to translate the received signals into suitable form for further processing, in the manner disclosed generally for operation of microprocessor 500, in the specification of '274.

Although a single probe 16 is shown in Figure 1, it should be understood that a second probe 16' may be coupled to the first probe 16 by a relatively short and manageable cable 17, in the event that it is desired to have the probes interact with each other; such interaction is particularly desirable and/or necessary for sensing of parameters requiring concurrent spaced apart sensing locations such as voltage or potential difference, or electrical resistance or current flow, for example. The coupled-together probes 16, 16' may be substantially identical to each other with respect to their sensing function, although only one of the probe units need be equipped with control switch means such as is described in the '274 patent, and with a transmitting antenna 1600 and related transmitter 1650.For sensing parameters such as voltage, amperes, ohms and the like, probes 16, 16' as shown in Figure 6, are provided with "contact" sensors 18, 18' in elongate stalk-like form, having sensing elements 19, 19' at their free ends, usually in the form of electrically conductive tips. Tip elements 19, 19' are electrically coupled to the circuit components within one of the probes 16, 16' in any well-known manner, to provide a signal suitable for transmission via antenna 1600, as described herein.

It is believed that the relationship between operation of a test meter assembly of this invention, and the invention disclosed in incorporated reference patent '274 will be understood readily by those having skill in this art. Suitable radio frequency transmitters and receivers are illustrated for example, by model numbers V-1001 and F-2003, respectively, available from Binsfield Engineering. Audio and visual display devices illustrated schematically by reference numeral 1700, in Figure 1 herein, will be understood to correspond generally to the function and operation of components such as LCD display 530, and speech synthesizer 540 and related components shown in Figure 6 of '274 and disclosed fully in the related text therein.

Probe 16 illustrated in Figure 2 herein, should be recognised to correspond functionally in all significant respects, to probe 16 disclosed in '274, subject to the addition of appropriate radio frequency transmitter 1650 together with suitable associated power supply means 1602 and/or 1603 (shown in Figure 3), to supply operating power for transmitter 1650.The power supply means 1602 or 1603 illustrated in Figures 2 and 3 herein, comprises one or more conventionally available storage batteries (not shown) which may be either rechargeable or non-rechargeable without affecting the scope or operation of this invention; and an electrical connection 1604, 1604'5 for coupling the probe, when desired, to an electrical source of operating or recharging electrical energy in any of the manners and forms now widely used and available for battery-powered portable electrical and electronic power equipment.

In the alternate embodiment of this invention represented by the partial block diagram of Figure 4, probe 16 is coupled to meter unit 1000 by an infrared transmitter 1650A associated with the probe and by an infrared receiver 1200A associated with meter unit 1000. Transmitter 1650A and receiver 1200A function in a conventional and well-known manner to transmit information signals via radiant infrared wave energy from probe 16 to meter unit 1000. Suitable infrared transmitters and receivers are illustrated for example, by model numbers 110-100 and 110-200, respectively, of the 110 Series of infrared transmitting and receiving equipment manufactured by Novalynx.It is recognised that infrared signal transmission is, in effect, a line-of-sight phenomenon; accordingly for applications in which it may not be convenient to maintain a suitable line orientation when the transmitter is mounted on a movable probe, the probe may be coupled to a substantially stationary transmitter by means of a relatively short length of flexible cable which will not be subject to the problems associated with substantially longer conductive cables that carry primary information signals between the probe and a meter unit in prior art test meter devices. The stationary transmitter then may be aimed directly and accurately at the relatively stationary receiver associated with the meter unit 1000.

In the further embodiment of this invention represented by the partial block diagram of Figure 5, probe 16 is coupled to meter unit 1000 by an optical fibre cable 1800 which carries light wave signals from optical transmitter 1650B associated with the probe to an optical signal receiver 1200B associated with meter unit 1000. Transmitter 1650B and receiver 1200B function in a conventional and well-known manner to transmit information signals using light wave energy propagated along optical fibres from probe 16 to meter unit 1000. Suitable infrared transmitters and receivers are illustrated for example, by model numbers 5843 and 5844, respectively, of the line of optical fibre transmitting and receiving equipment manufactured by Dymec, Inc.It will be apparent to those having skill in this art, that optical fibre cable may be manufactured with sufficient length, diameter and degree of flexibility necessary to permit convenient use and manipulation of hand-held probe 16 for its intended application in various test environments.

In the still further alternate embodiment of this invention represented by the partial block diagram of Figure 7, probe 16M is coupled to meter unit 1000M by an acoustic signal transmitter 1650M associated with the probe and by an acoustic signal receiver 1200M associated with meter unit 1000M. Transmitter 1650M and receiver 1200M function in a conventional and well-known manner to transmit information signals via radiant sound wave energy from probe 16M to meter unit 1000M. Suitable acoustic signal transmitters are illustrated for example, by OMEGA model HHM1 or model PTVC-756 Portable Transaction Voice Computer in the voice synthesis mode as manufactured by Voice Connection/CCSI of 8258 Kingslee Road, Bloomington, MN 55438 and suitable acoustic signal receivers are illustrated for example by model IntroVoice V as manufactured also by Voice Connection/CCSI.

In the further and final alternate embodiment of this invention represented by the partial block diagram of Figure 8, probe 16P is coupled to meter unit 1000P by an electromagnetic signal transmitter 1650P associated with the probe and by an electromagnetic signal receiver 1200P associated with meter unit 1000P. Transmitter 1650P and receiver 1200P function in a conventional and well-known manner to transmit information signals via radiant electromagnetically-coupled wave energy from probe 16P to meter unit 1000P. Suitable electromagnetic signal transmitters are illustrated for example by, an audio amplifier of sufficient wattage, say for example a Bogen model CTS1 100, with its output electrically connected to approximately 12 turns of insulated 18 gage copper wire wound in the form of a loop placed around the zone to be energized.

The impedance of the loop would be matched to the output impedance of the amplifier for maximum efficiency. Suitable electromagnetic signal receivers are illustrated for example, by a pick up coil such as a standard telephone pick up, such as Radio Shack model No. 44-533, with its coil oriented in the same plain as the transmitting loop and located within the energized zone of the same. The output of the telephone coil would be connected to the low level microphone input of a standard audio amplifier similar to the Bogen amplifier used for the transmitter. The output signal of the receiving amplifier would be a duplication of the input signal to the transmitting amplifier.In this embodiment of the invention, electromagnetic signals are created in a magnetic loop 1651P which is circumscribed by a larger loop or coil of magnetic wire or suitable conductor 1201P which serves as a receiving means in which electromagnetic signals representative of the signals present in the transmitting loop 1651P are duplicated by electromagnetic induction, in a well known manner. It will be apparent to those having skill in this art that the relative positions of the transmitting loop 1651P and the receiving loop 1201P may be interchanged if desired, and the outermost loop may be arranged to substantially surround a desired work area so that the probe may be moved about freely within the work area without adversely affecting the desired coupling of the electromagnetic signals from the probe to the test meter.

Probe unit 16, illustrated in Figure 2, incorporates power supply means 1602, 1603, as previously mentioned. Alternative separable power supply means in the form of battery holder 1602 and external electrical connector 1604 are shown in Figure 2. A standard and readily available power switch, not shown may be included in a well-known manner in the internal circuitry of the probe, to assure that battery supply 1601 and external electrical supply through connector 1604 do not interfere with each other when power is received from the external supply. The means for connecting an external source of electrical energy to connector prongs 1604 is illustrated clearly in Figure 3 of the drawings herein.The detachable handle 1660, configured to be gripped conveniently by a human operator if desired, incorporates an electrical cable for convenient connection to an external source of electrical power (not shown), and a mating electrical connector half 1605 mounted on the handle for electrical and mechanical coupling to the cooperating connector half on the probe 16 represented by connector prongs 1604.

To further facilitate use of probe 16 as a testing, sensing and monitoring instrument, the body of the probe is provided with an internally threaded socket element 1680 for securing the probe body to a standard tripod or similar support in a well-known manner.

The specification and drawings herein set forth clearly and fully describe preferred embodiments of this invention, but it should be readily apparent to those having skill in this art that other forms, embodiments and variations thereof may be conceived and constructed without departing from the scope of the following claims.

Claims (13)

1. A sensing probe assembly, for an electrical test meter of the type having a microprocessor responsive to electrical signals for changing various aspects of the test meter display and operating mode functions, said probe assembly comprising a first universally movable sensing probe having a probe housing; a wave energy signal transmitter mounted on said probe housing; first power supply coupling means mounted on said probe housing and electrically coupled to said wave energy signal transmitter for coupling a source of electrical energy thereto; a first sensor mounted to said probe housing for sensing a parameter of an external object; said sensor being electrically connected to said wave energy signal transmitter for delivering thereto an electrical signal representative of a sensed value of said parameter; said wave energy signal transmitter being electrically coupled to the said first power supply coupling means for transmitting externally of said probe housing in wave energy form, a single representative of a sensed value of said parameter, for receipt by a test meter unit having a wave energy receiver associated therewith.

2. A sensing probe assembly in accordance with Claim 1, further comprising a second sensing probe having a second sensor mounted thereon; an electrical cable electrically connecting said first sensing probe to said second sensing probe; said second sensor being electrically coupled to said wave energy signal transmitter via said electrical cable for producing a signal indicative of an electrical condition existing between one external object in contact with the said first sensor and a second external objection contact with said second sensor.

3. A sensing probe assembly in accordance with Claim 1 or 2, further comprising microprocessor means electrically coupled between said sensor means and said wave energy signal transmitter means for generating digital signal representative of said sensed parameters to be delivered to said signal transmitter for transmission externally of said sensing probe.

4. A sensing probe assembly in accordance with Claim 3, further comprising manually operable control switch means coupled to said microprocessor means for generating signals to be transmitted externally of said sensing probe to control the operation of a test meter having a wave energy receiver associated therewith.

5. A test assembly in accordance with any preceding Claim, wherein said first power supply coupling means is a storage battery receptacle.

6. A sensing probe assembly in accordance with any one of Claims 1 - 5, wherein said first power supply coupling means is a separable electrical connector half capable of being mechanically and electrically coupled to a mating connector half that is electrically coupled to an external source of electrical energy.

7. A sensing probe assembly in accordance with any one of Claims 1 -5, wherein ii first power supply coupling means is one-half of a separable electrical connector, and said first universally movable sensing probe further includes a detachable handle member having a mating-half of a separable electrical connector mounted thereto for mechanically and electrically engaging said one-half of said separable electrical connector; said detachable handle portion having connection means thereon for electrically connecting to a source of electrical energy.

8. A sensing probe assembly in accordance with any preceding Claim, wherein said transmitter generates radio frequency wave form signals for aerial transmission to said receiver, and said receiver is a radio frequency receiver.

9. A sensing probe assembly in accordance with any one of Claims 1 - 7, wherein said transmitter generates infrared light wave signals for aerial transmission to said receiver and said receiver is an infrared light wave signal receiver.

10. A sensing probe assembly in accordance with any one of Claims 1 - 7, wherein said transmitter generates optical light wave signals for transmission via optical fibre cable; said receiver is an optical light wave receiver, and said sensing probe assembly further comprises an optical fibre cable coupled to said transmitter for accepting light wave signals there from and coupled to said receiver for delivering optical light wave signals thereto.

11. A sensing probe assembly in accordance with any one of Claims 1 - 7, wherein said transmitter generates audio frequency wave signals for transmission via said wave energy signal transmitter mounted on said probe.

12. A sensing probe assembly in accordance with any one of Claims 1 - 7, wherein said transmitter incorporates a closed conductive loop for transmitting electromagnetic waves capable of creating an induced electromagnetic signal within a separate conductive loop when such a separate loop is positioned substantially coaxially with said closed conductive loop.

13. A sensing probe assembly for an electrical test meter substantially as described herein with reference to the drawings.