GB2176329A - Room service call systems - Google Patents

Abstract

Room service call systems to provide facilities of greater assistance to the staff than conventional bell-call systems. To avoid a member of staff having to move to a display panel indicating a particular room number when a call is initiated, which could mean the staff member moving away from the room concerned, the users are provided with call switches (5) to trigger associated coder units (3) which signal to a central control (1) which decodes each received signal to identify the relevant room number, generates a speech sequence and issues a verbal message via a distribution amplifier (6) to loudspeakers (4) distributed as required. Each loudspeaker may be normally inhibited, the inhibition being overridden when a staff member comes within range, the staff member carrying a signal generator for this purpose. The inhibition may be generally suspended when required. Means for staff to initiate messages may be provided. <IMAGE>

Description

SPECIFICATION Room service call systems The invention relates to room service call systems of the type used in hospitals, nursing homes and hotels, for example, where a signal can be initiated by pressing a switch or pulling an operating cord which initiates a signal indicating to the staff that attention is required in a particular room.

The majority of systems currently employed operate a central control panel which indicates the room number and issues an audible call signal tone or a visual calling lamp, or both.

Even if a plurality of satellite display panels are provided at strategic points, such systems still have the serious disadvantage that a nurse working in a particular corridor has to go to the nearest display panel, and this may actually involve her moving away from the room requiring attention.

One object of the present invention is to provide a system which avoids such disadvantages and offers the maximum of convenience to the staff with the minimum of disturbance to patients or other users.

According to a preferred embodiment of the invention, there is provided a room service call system in which a plurality of call switches are provided each attached via a respective coder unit on a common line to a central unit which includes means for decoding each received signal to identify the relevant coder unit and code message, means to generate a speech sequence identifying the room number or location of the particular coder unit that has been operated, and to generate an appropriate verbal indication of the action to be taken, said central control unit feeding this speech sequence via a distribution amplifier to a plurality of loudspeakers distributed about the building.

In a preferred embodiment, where calls are to be emitted throughout a rest period or night period, a number of the loudspeaker units may incorporate an inhibit switch arranged to suppress the audible output of normally audible signals in the absence of an over-riding release signal that is produced by a respective generator provided in staff members units, which generator transmits continuously as the staff member proceeds on the duty round, and the transmitted release signal being adapted to operate an inhibit-release switching stage in the call-signal path to the associated loudspeaker of any coder unit within range and so allow any call-up signal for service to be announced by the associated loudspeaker units, for the benefit of any staff members in the vicinity.

In this way it is possible to reduce the overall disturbance to the general number of patients, if an urgentiy sick patient calls for attention, or if a psychiatrically disturbed patient makes repeated non-urgent calls, because staff will be aware of the situation as soon as they move within range of a loudspeaker, but these loudspeakers will not be issuing all audible signals at any time throughout the night, or any other rest period, but only when there is a staff member within ear-shot.In this arrangement it is therefore possible to reduce patient-disturbance to an absolute minimum, whilst ensuring maximum efficiency, as there can be conveniently located basic staff-unit loudspeakers that are continually operative, whilst master controls can be provided to inhibit this suppressed mode of operation and issue a general call for the benefit of those patients requiring more urgent attention, and individual staff-units could be provided with reception means for an overall monitoring function to release a call relevant to their specific duties, upon transmission of a special signal from the central control unit, even if not within their immediate vicinity at any instant.

A further advantageous mode of operation is available, in which a selection of priority ratings are allocated, i.e. so that call-switch units allotted to patients may incorporate a key-switch operable only by a staff member, to produce a specific message or emergency call that recipients will know, by its content, to be a call initiated by a staff member, and not a patient. Individual key-switches may be provided at convenient points, for u se by the staff to produce any one of a plurality of special messages.Furthermore, where members of the staff carry a generator to transmit a release signal, as described above, then patients' call-switch units can be provided with an auxiliary staff-operated key-switch to initiate a selected synthesized message when operated by a transmission from the staff member s generator, which is designed to transmit a predetermined code recognisable in any respective key-switch that is within range, and thus enable a member of the staff to instantly trigger a staff call priority message from wherever that member of staff may be, within the working bounds of the system, thus eliminating the need for that staff member to leave a patient found to be in some difficulty, but away from his or her bed.Once again, the coding can be selective to determine the nature of the call, and the synthetic message content will be recognisable to all staff as a call triggered by a fellow member of the staff, and not by a patient. Thus valuable time may be saved in an emergency.

When using the proposed system, any member of staff hearing the message instantaneously known the room number and can move directly in the required direction to give the most prompt attention.

Other advantageous features of the system will be described with reference to the drawings, in which: Figure la is a block schematic circuit dia gram of one preferred embodiment; Figure 1 b illustrates a portable signal generator as carried by members of the staff at any site at which the system is installed; Figure 2 is a simplified block schematic diagram of the central control unit of a more sophisticated embodiment of the invention; Figure 3 illustrates details of a coder unit for use in the system in Figure 2; and Figure 4 shows details of a speaker unit for use in this system.

The relatively simple system illustrated in Figure 1a is intended primarily for use in nursing homes, or residential establishments for the elderly, and will be referred to as a verbal nurse call (VNC) to emphasize that in normal use the system avoids the use of bells or signal lamps, and directly issues a synthetically-produced spoken message, for example, "Nurse Assistance-Room 10".

The central control unit 1 is connected via at least one signal line 2 to a cascade of coder units 3 and corridor loudspeakers 4.

Each coder unit has a call switch 5 attached thereto to initiate a pulse burst which, in a simple embodiment, may consist of two fourbit consecutive code groups, enabling ninetynine different room numbers to be utilised.

Each call switch may be a simple press-button or pull-cord or, where patients suffering from some serious disability or handicap are involved, a specially-adapted call sensing device may be used such as a pressure pad or a pneumatically-operated device. Obviously more than one call switch could be connected to a coder unit and/or more than one coder unit could be provided in a room, depending upon the particular problems that have to be taken into account in any particular installation.

As a further advantageous feature, the coder unit or the central control unit itself may be provided with means to detect repeated operation of a call switch and, in the event of a switch being operated more than three times within a given time period for example, the system responds by introducing the word "Urgent" into the verbal announcement, As will be described later, if an embodiment provides for priority ratings, the new urgent call would be automatically up-graded to take precedence over routine calls.

In order to avoid possible embarrassment or alarm, the use of a verbal message may be exploited to introduce coded announcements whose meaning will be significant to members of the staff but not alarming to the patients, residents, or the like. For example, if a specific monitoring device is used as a call switch to activate in the event of a cardiac arrest or lung collapse condition, the resultant verbal message can utilise a selected term, such as a given Doctor's name, in the verbal announcement, the staff being instructed to act with appropriately urgent response on hearing such a call without causing any general alarm.

The central control unit 1 preferably includen means to automatically repeat the announcement at regular intervals, until the call is cancelled via the coder unit by operation of an ATTENDENT RESET push-button that is provided on or adjacent the coder unit for that particular call switch. The central control unit is also provided with means to expand the signal sequence in the event of a second call arriving before a first call has been cancelled, in which case, both relevant room numbers will be stated in each announcement.

The room numbers are inserted in their numerical sequence, to make the announcements readily understandable, and the numbers omitted when attention has been prowided.

The coder units 3 may be provided with preset buttons, or key-switches, as represented by the push-button 3a in the illustrated embodiment, which enable the staff to prepare any selected coder unit to initiate a special verbal request, which may be particularly useful if the attention required involves the provision of special medication or equipment, For example, a patient receiving oxygen may be given a supplementary call switch 5 in addition to the switch provided for normal operation, which can be operated to initiate a verbal message such as "Fresh Oxygen Supply Required in Room 73".

At the central control unit 1 a two-digit display 1a can be provided, to be illuminated as a visual indication of the particular room initiating a call. When there are a plurality of calls in operation, the display device steps through them in sequence.

In this embodiment, each coder unit 3 has a pulse-code generator 3b, which is set up to initiate a code unique to that room, or the particular switch if separate switches 5 are provided, in which case a separate designation may be incorporated in the synthesized message, such as "Nurse Assistance -Room 37-Blind Patient", or any other potentially useful information.

A standardised connection is desirable to keep costs to a minimum, and enable simple telephone cable to be used, so that three channels of communication are provided, for power supply, code relay, and speech output to the loudspeakers 4. Selected loudspeakers may be provided with a digital display 4a, controlled by a decoder similar to that provided in the central control unit. The speakers are connected in parallel to the output of a distribution amplifier 6, and although a common line has been shown, as a preferred arrangement, it will be appreciated that an additionai output line may be used to the speakers, or as a spur to selected speaker units remote from the rooms provided with coders.

The embodiment shown is also provided with a staff-call microphone 7 which can be operated by a member of the staff to make announcements whenever necessary. The operation of this microphone over-rides the normal operation of the central control unit, and the latter resumes its normal operation after the the microphone 7 has been switched off.

In order to provide for night use in situations where the verbal announcements could be disturbing, selected loudspeakers 4 may be muted, particularly those provided with a digital display, and/or the volume may be reduced to some extent, and an additional start tone inserted to attract the attention of the staff on duty. Additionally, or as an alternative for night use purposes, a special line may be run to speakers 8 provided in duty staff quarters, in which case each synthesized announcement may be preceded by an audible tone to attract attention, the means being provided in the central control unit 1.

Some loudspeaker outlet units may incorporate an inhibit switch 3b', used to suppress the audible output of normally audible signals at some or all patient-associated units in the absence of an over-riding release signal produced by a respective generator 9 (Figure 1 b) in any staff members portable unit, which generator transmits continuously as the staff member proceeds on the duty-round, the transmitted release signal being adapted to operate an inhibit-release switching stage in the call signal path to the associated loudspeaker and so allow any call-up signal for service to be announced by those loudspeaker units that are within range of the staff members release-signal generator.

In this way it is possible to reduce the overall disturbance to the general number of patients, if an urgently sick patient calls for attention, or if a psychiatrically-disturbed patient makes repeated non-urgent calls, because staff will be aware of the situation as soon as they move within range of a loudspeaker, but these loudspeakers will not be issuing audible signals at any time throughout the night, or any other rest period, but only when there is a staff member within ear-shot.In this arrangement it is therefore possible to reduce patient-disturbance to an absolute minimum, whilst ensuring maximum efficiency, as there can be conveniently located basic staff unit loudspeakers that are continually operative, whilst master controls can be provided to inhibit this suppressed mode of operation and issue a general call for the benefit of those patients requiring more urgent attention, and individual staff units could be provided with reception means for an overall monitoring function to release a call relevant to their specific duties, upon transmission of a special signal from the central control unit, even if not within their immediate vicinity at any instant.

In order to maintain a room service facility in the event of a failure of the verbal message synthesizer or its amplifier, an electronic alarm unit 1 b is provided in the central control unit which operates to generate a recognisable warning note whenever a call is initiated during the failure of the normal message-producing equipment, and thus the staff can still utilise the equipment by referring to the digital display in the manner of a conventional bellcall system.

It will be apparent that the circuit details of the units required can take many forms, and the means for producing the synthesized verbal message can itself be designed in several different ways. A set of tape loops having respective magnetically-recorded or opticallyrecorded words or phrases can be utilised, with appropriate selective switching to build up the required message at any time, or a reel of tape carrying the requisite speech on a track parallel to an indexing control track can be used, although this might require intermediate storage to avoid a disjointed message being transmitted in the event of the tape having to be wound through a relatively long section to locate the next word or phrase. Preferably the arrangement of a solid-state voice synthesizer will be u sed because of the greater reliability and reduced power consumption and size.

The use of some form of key or code-ope rated switch 3a to generate staff-initiated calls can be extended to utilise the inhibit switch 3b' operable by a signal from the generator 9 carried by a staff member.

The generator 9 shown in Figure 1 b has a square-wave oscillator 11, operated in pulsed fashion by a pulsing timer stage 12 and an output stage 13. In this embodiment the generator produces a 39,6 KHz square wave, and is pulsed to be on for 1 millisecond and off for 25 milliseconds, to achieve battery economy and enable the inhibit switch 3b' to be provided with logic analysis circuitry to distinguish staff call transmission from other transient sounds. A key 14 may be provided on the generator 9 to enable a modified transmission which can be detected to trigger a special call by remote operation.

An alternative embodiment will now be described with reference to Figures 2, 3 and 4.

This is a more sophisticated system than that described with reference to Figures 1a and 1 b, and is intended in particular for larger installations, and for locations where more complex facilities are required, but the basic elements 1 to 14 of the embodiment shown in Figures 1a and 1b are arranged in the same fundamental configuration, and where possible and relevant the features of this second embodiment will be identified by the reference numerals used for the corresponding feature of the first-described embodiment, In general termn the coding system may take any one of the several known forms commonly used for discrete stations on a common line. A multiconductor connection cable, a common data bus with parallel mode code transmission and analysis, or series mode coding can be used, alone or in a combination, as the situation may require.However, to keep installation costs to a minimum where a large building or complex has to be covered, it is advantageous to use a simple 6wire telecommunication type line 2 extending from the control unit 1, with the coder units 3 and corridor loudspeakers 4 attached across the line by respective junction boxes (not shown). Spurs may be employed where economy or convenience makes this arrangement desirable. With such a line, the central control unit 1 may take the form shown schematically in Figure 2. The line 2 continually feeds out a supply current, and sends synchronising clock signals whenever there are no audio signals being transmitted, and a return channel receives the coded trigger signals from the coder units 3, or from any corridor speaker 4 provided with remote or manually-operable staff-call detection means.A stabilised power supply 21 provides power for the control unit and the remote units, in normal operation, but a stand-by battery 22 is provided for use in the event of mains failure. It also supplies a stable low-level output for the logic circuits and synthesizer. A power amplifier output stage 23 of the distribution amplifier 6 supplies the messages produced from a solidstate synthesizer 24 under the influence of a logic array and EPROM in a decoder stage 25 that receives any incoming signals. The staff microphone 7 can be used for over-riding the normal operation and issuing general or emergency announcements and paging calls. The logic array and EPROM select required phrases and numbers, and stores them for repeated announcements in numerical sequence in each of a plurality of predetermined priority rankings.A master oscillator 26 controls the logic analysis and synthesizer operation, and feeds clock pulses to all remote units when speech is not being transmitted. This enables respective slave counters 31 in remote units to be held in synchronism with the master counter 26, and so enable any calling unit to be identified by the instant in each counting cycle that corresponds to the 7-bit address allotted, when it then responds by a coded clamping of selected pulses, thus providing an effective time-division-multiplex arrangement.The master counter is arranged in this embodiment to operate as a 12-stage binary counter with a 1 KHz oscillator drive, to step for a count of 2048 pulses, and then remain at the logic "high" state for a period of 30 milliseconds, which causes all counters to reset to zero, in case any transient interference has caused a slave counter to get out of step. The stored messages are repeated after a pause intro duced by a timer section of the logic array.

To provide for priority ranking the slave counters are each allocated a 4-bit address, and hold the line low during at least part of its address sequence, the period or periods identifying the priority, and the time in the overall cycle indicating the particular location of the call. Thus, it is possible to operate with a basic normal call priority, which can be upgraded to an "urgent" call if the patient repeatedly operates the relevant call switch, or a staff member takes the requisite action, as will be described. For any special emergency, a higher priority ranking is provided for initiation only by staff members, selecting the appropriate ones of the four clock positions are held low. Finally, a top priority is provided for use with monitoring equipment, to indicate conditions such as cardiac arrest, which in this case holds all four pulse periods low.

The identity or location of the calling unit, indicated by its position in the clock sequence can be adapted to the requirements of a particular installation, and to facilitate this each unit is provided in standard form with the necessary interconnections to be made on site.

Thus the standard choices are a single sequence from 1 to 125; or a sequence from 101 to 163 followed by 201 to 262; or three sub-sequences, 101 to 141, 201 to 241, 301 to 342; or finally a five-sectioned sequence, 101 to 125, 201 to 225, 301 to 324, 401 to 424 and 501 to 524. Although the room number is advantageously used, it will be appreciated that the logic array and EPROM can be adapted to translate a "system number" into the correct relevant room number or location, if local requirements make such an arrangement necessary.

Figure 3 schematically illustrates details of the coder units 3 with call switch 5 and a local speaker which is rendered operative when that unit call switch is operated so that the patient is reassured. The code generator 3b comprises a slave counter and a coding link array, as described above, to provide a response at that time in the master counter cycle when its allotted number is present, and to clamp the one or more selected pulses to indicate the priority. Secondary call switches 5', monitoring and/or special code buttons may be provided, as described for the first embodiment. A receiver 3c enables any staff generator 8 to release the inhibiting circuit or its loudspeaker, and can automatically trigger a remote call if the staff member takes the necessary action, Figure 4 schematically represents the details of a corridor speaker 4, with a digital display 4a, its inhibit stage 4b and receiver 4c, which is provided to detect any staff generator signal and render the speaker unit operative. An emergency key 4d enables staff to manually trigger any appropriate message in predetermined circumstances for any given installation.

Claims (14)

1. A room service call system in which a plurality of call switches are provided each at tached via a respective coder unit on a common line to a central unit which includen means for decoding each received signal to identify the relevant coder unit and code message, means to generate a speech sequence identifying the room number or location of the particular coder unit that has been operated, and to generate an appropriate verbal indication of the action to be taken, said central control unit feeding this speech sequence via a distribution amplifier to a plurality of loudspeakers distributed about the building.

2. A system as claimed in Claim 1, in which said central unit includes means to react to each incoming call and insert the associated room number in its numerical sequence in an announcement containing the room numbers still requiring attention.

3. A system as claimed in Claim 1 or Claim 2, in which said central unit includes means to utilise specific names or words to convey coded sequences to the staff.

4. A system as claimed in any preceding Claim, in which said central unit includes means to automatically include an urgency indication in the event of any given call not receiving attention within a predetermined period of time.

5. A system as claimed in any preceding Claim, in which a said coder unit has a plural ity of call switches attached thereto, and incorporates means to indicate which patient-call switch has been operated.

6. A system as claimed in any of Claims 1 to 4, in which a said coder unit has a plurality of call switches attached thereto, each code to indicate a different service requirement for one patient.

7. A system as claimed in any preceding Claim, in which a said coder unit is provided with monitoring means to automatically initiate a call on detecting a significant change in the condition of a patient.

8. A system as claimed in any preceding Claim, in which means are provided to reduce the volume of the announcements and insert an alarm tone to attract the attention of duty staff for use during rest periods.

9. A system a s claimed in any preceding Claim, in which said central unit is connected via one or more separate lines to night duty outlets provided in duty staff quarters, each outlet emitting an alert tone prior to emission of the verbal message.

10. A system as claimed in any preceding Claim, in which at least one digital display panel is provided indicating the room numbers requiring attention, one at a time in numerical sequence.

11. A system a s claimed in Claim 10, in which safety means are provided to operate in the event of any breakdown in the means for producing the verbal messages which respond to any call by triggering an electronically-generated warning tone followed by display of the relevant room number or numbers of the or each digital display.

12. A system as claimed in any one of Claims 1 to 11, in which at least one loudspeaker outlet unit incorporates inhibit-switch means which suppress the output of a call unless operated by a release signal transmission from a portable generator carried by each staff member.

13. A system as claimed in any one of Claims 1 to 12, in which there is at least one key-switch, alone, or combined with, a patient s call-switch and operable by a predetermined key-member or control signal sequence to trigger the generation of a speech nequence message whose content indicates that it is staffinitiated.

14. A room service call system substantially as described with reference to the accompanying drawing.