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Número de publicaciónUS3228020 A
Tipo de publicaciónConcesión
Fecha de publicación4 Ene 1966
Fecha de presentación19 Sep 1963
Fecha de prioridad19 Sep 1963
Número de publicaciónUS 3228020 A, US 3228020A, US-A-3228020, US3228020 A, US3228020A
InventoresJr Irvin Gassenheimer, Gassenheimer Irvin
Cesionario originalJr Irvin Gassenheimer, Gassenheimer Irvin
Exportar citaBiBTeX, EndNote, RefMan
Enlaces externos: USPTO, Cesión de USPTO, Espacenet
Room status indicating system
US 3228020 A
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Jan. 4, 1966 1. GASSENHElMER ETAL 3,223,020

ROOM STATUS INDICATING SYSTEM Filed Sept. 19, 1963 2 Sheets-Sheet 1 REEN IGHT MRJOHN DOE 9 MR$MRS L. SMITH FLASH ER R A: POWER MESS E SUPPLIES 36 FORY MAIDS KEY ME Al-E F3 TU g F 16. l 301 ML YSAC-i FOR (0L4 Fan mu. INVENTORS IRVIN GASSENHElMER BY IRVIN GASSENHEIMER, JR.

1966 1. GASSENHEIMER ETAL 3,228,020

ROOM STATUS INDICATING SYSTEM 2 Sheets-Sheet 2 Filed Sept. 19, 1963 ZOEEOU ZOEEOU A INVENTORS IRVIN GASSEN HE IMLER AND lRVI N GASSEN HE1MER,JR

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ATTORNEKS United States Patent 3,228,020 RQOM STATUS INDICATING SYSTEM Irvin Gassenheimer, 3138 Bankhead Ave., and Irvin Gassenheimer, Jr., 3517 Bridiewood Drive, both of Montgomery, Ala.

Filed Sept. 19, 1963, Ser. No. 310,085 8 Claims. (Cl. 340-286) The present invention relates to a signalling system and more particularly to a signalling system for hotels, motels and like establishments.

In the operation and supervision of hotels, motels or like establishments, it is desirable to :provide signals at various locations, particularly at the clerks desk, housekeepers station and individual rooms to indicate certain conditions, such as the presence of a chambermaid or other attendant in the room, the time when he or she has finished the work therein, the time when a guest has checked out of a room and the room requires attention, the time when the room is ready for occupancy, the time when the room is occupied and also when a message is received at the clerks desk for an individual guest.

Accordingly, it is an object of this invention to provide an improved signalling system for indicating at various locations, the room status and maid service requirements of individual rooms in a hotel or the like.

Another object of this invention is to provide an improved signalling system for indicating at various locations in a hotel or the like, the presence of an attendant in a room and the time when the attendant has completed his or her work.

A further object of this invention is to provide an improved signalling system for hotels and the like, which signals a guest to apprise him of a message at the clerks desk.

Yet another object of this invention is to provide an improved signalling system for hotels or the like which utilizes a minimum number of conductors and which is extremely simple in operation and economic in construction.

In carrying out the present invention, there is provided a control console located at the clerks desk or receiv ing station of a hotel or the like, which provides an instant indication of the status of each room in the establishment. The console is provided with a rack having a plurality of slots corresponding to the various rooms. Each slot has adjacent thereto a switch and visual indicating means which are operatively interconnected to other stations to provide the room status indication. Selective positioning of the switches energizes the indicating means at the control console to signal to the clerk and to the housekeeper the status of the individual rooms by energizing visual indicating means at preselected remote locations. The visual indicating means at the preselected remote locations comprise remote consoles having indicating means corresponding to the indicating means at the control console and selectively energized in accordance with the positioning of the switches. Each room is provided with an individual indicating means and control means for indicating at the other locations the presence of an attendant in the room and when the room is ready for occupancy.

In accordance with another feature of the invention, each room indicating unit is operatively interconnected to the remote location by only one pair of conductors for each room and one looping or common pair of conductors between rooms. Separate A.C. and DC. power sources are utilized and a rectifier electrically interconnected to the DC. circuit at each individual room indicating unit is utilized to prevent the DC. current from energizing the room indicator when the switch at the control unit is placed in one of its selective positions. A flasher is pro- 3,228,020 Patented Jan. 4, 1966 vided in the AC. circuit to provide a flashing signal at the room upon selective positioning of a switch at the control console in another of its positions, thus enabling the same conductors and same indicating means to be utilized for indicating and signalling the status of the rooms and when a message for 'a guest has been received.

The present invention accomplishes all of the foregoing in a reliable and eflicient manner. The system indicates the room status and maid service requirements of each room in a hotel, motel or like establishment and provides for more efiicient employment of personnel while making room status information immediately available at the clerks desk. In addition, there is provided a message signal system utilized to notify a guest of a message, thereby eliminating the employment of bellboys for the delivery of such messages or the repeated calls from the switchboard to an absent or sleeping guest.

It should now be apparent to those skilled in the art that the present invention in every way satisfies the objectives discussed above. Changes in or modifications to the embodiments illustrated above may now be suggested without departing from the present concept. Reference should be had to the appended claims to determine the scope of this invention, and while the specification concludes with claims particularly pointing out and distinctly claiming the subject matter regarding the invention, it is believed that the invention will be better understood from the following description taken in connection with the accompanying drawings.

FIG. 1 is a diagrammatic representation of the room status indicating system as applied to a motel in accordance with the present invention; and

FIG. 2 is a schematic circuit diagram of the present invention illustrating the electrical connection for three separate rooms.

Referring now to FIG. 1, the signalling system is illustrated generally in block form in conjunction with the operation of a motel and comprises three separate stations designated by the letters A, B, and C. Station A represents the position of the desk clerk, Station B represents the position of the housekeeper, and Station C represents the position of the rooms. At Station A, there is provided a control console designated generally by the numeral 10. The console is divided into two sections 11 and 12. Section 11 is provided with a plurality of switches which may be arranged vertically in a column 13. Adjacent the rows of switches are provided two columns, 14 and 15, of indicating means such as lamps which are selectively energized by the positioning of the corresponding switches. Each column of lamps has associated therewith lenses of different color which may be green for column 14- and red for column 15 and which may be conveniently identified by the letters G and R, respectively.

Thus, section 11 of the control console comprises a matrix of switches and indicating means comprising three vertical columns 13, 14 and 15 and a plurality of horizontal rows, each row including a switch 16, a green indicating means 17 and a red indicating means 18. Hereinafter, when reference is made to a green lamp or red lamp, it should be understood that the lamp need not be of such color, but that the color is provided by the.associated lens and, although the invention is to be described with reference to green and red indicating lamps, any other suitable colored indicators may be used or the indicators may be of one color. However, in the preferred embodiment, two colors are utilized to accentuate the indication. Each switch 16 controls the energization of of those lamps located in the corresponding row and is electrically interconnected in such a manner as to energize the lamps in various combinations. Each possible combination of energization of the lamps corresponds to a particular condition of the room.

Section 12 of the console is in the form of a rack having a number of slots 19 associated with each row, one for each room of a hotel, and which are identified by corresponding room numbers 300, 301, 302, etc. In the use of this part of the rack, the desk clerk, when a room is rented, fills out an appropriate identification card with the name of the occupant, his address and other desirable information as is normally done in the course of renting a room and places this card in the appropriate slot in the section 12 of the console 10. As seen in the drawing, the slots corresponding to rooms 303 and 304 have located therein cards corresponding to guests who have rented the rooms. It should be readily apparent that each control console may include one or more complete units such as sections 11 and 12 in a single housing. The number of such units will, of course, depend on the number of rooms available for occupancy.

At Station B, there is provided a remote console or hous keepers panel 20, having a plurality of sets 21 of indicating means such as lamps, each set corresponding to a row of lamps at the control console and arranged to be energized in correspondence therewith. Each lamp is provided with a suitable colored lens as hereinbefore described whereby selective positioning of switch 16 energizes the corresponding lights at the remote console to indicate to the housekeeper the particular status of the room so that, if necessary, the proper attendant may be dispatched to service the room.

A remote console 20 may be provided at one or more locations and on as many floors as desirable. In the preferred embodiment, each floor is provided with a remote console having a plurality of sets 21 of indicating means arranged in rows a, b, c, and d, with each row corresponding to a wing or physical location of a group of rooms. Thus, not only is the status of the room indicated, but the physical location of the room is also noted. This is particularly helpful in ascertaining the location of various servants around the motel in accordance with another feature of the invention to be hereinafter described.

Station C represents the individual rooms of the motel, each room of which is provided with a separate room unit or maids panel 30. Each panel 30 includes a keyoperated switch or jack 31 and a signal lamp 32 to indicate the status of the room and maid service requirements. When a maid is dispatched to the room by the housekeeper or enters the room during the course of her normal rounds, the lamp 32 is in its deenergized condition due to the blocking effect of diode 50. It should be readily apparent that diode 50 may be left out of the circuit in which case the lamp 32 will be energized to indicate to the maid when she enters that the guest has checked out of the room. Such an arrangement oiTers a distinct advantage in that it permits the maid to recognize skip-outs, theft of items from the rooms, or presence of the guest by evidence of luggage.

Each maid is provided with a special key 33 or plug which is inserted into the key-operated switch or jack 31, as the case may be. This energizes both the red and green lamps at the control cons-ole 10 and remote console 20 indicating the location of the maid and that the particular room is being serviced. When the maid leaves the room, the key 33 is removed from the switch 31 and the red lamps which were originally energized under the control of the switch at the control console, are deenergized. However, the green lamps remain energized through appropriate control means indicating the room is ready for occupancy.

For signalling to a guest occupying a room that a message has been received for him at the clerks desk, a flasher 60 is arranged in the AG. supply line and electrically interconnected to each room unit 30 and the signalling system. The flasher may be of conventional design as, for example, a 115-volt, 60-cycle, one (1) rpm. motor having a fiber cam operatively connected to the motor shaft causing the making and breaking of a pair of switch contacts. Such interruption may occur at periods set by the cut of the fiber cam and is preferably set for make and break of periods of 1 /2 seconds, respectively. When a message is received for a guest, selective positioning of the switch at the control station 10 corresponding to the room energizes the flasher causing the lamp 32 to flash at 1 /2 -second intervals, thus apprising the guest that a message for him has been received at the clerks desk. When the guest calls for the message, the clerk returns the switch to its proper position to extinguish the light.

All of the stations are interconnected through suitable conductors 35 and in accordance with the present invention, each room unit is connected by means of only one pair of conductors and one looping or common pair of conductors. Suitable AC. and DC. power may be pro= vided from any conventional power source 36 which is commercially available and well known in the art to provide a first and second source of operating current.

Before discussing the operation of the system, reference is to be had to the various combinations or conditions of energization of the indicating lamps for indicating the status of the rooms. While each combination may be chosen to represent a particular room status indication as desired, the following combinations, for purposes of discussion, have been chosen. Energization of only the red lamps indicates to the desk clerk, housekeeper and maid that the room requires attention. Energization of both the red and green lamps at the control console and remote consoles indicates that the maid is in a corresponding room. Energization of the green lamps only indicates the room is ready for occupancy and when all lamps are extinguished or in their deenergized condition, indicates the room is occupied. A flashing light at the room unit indicates that a message has been received at the clerks desk for the occupant of the room.

Referring now to FIG. 2, there is illustrated the details of the circuit for the present invention. For convenience, only the equipment associated with three rooms are illustrated, it being understood that the circuit of all rooms is the same. Where appropriate, the reference numerals used in conjunction with FIG. 1 are also used in FIG. 2 to designate similar components, and those components located within a console are enclosed by dashed lines representing the console.

Referring now to FIG. 2, the control console 10 includes, for each room, a three-position switch 16, a green lamp 17, a red lamp 18 and an operating relay 41. Switch 16 comprises a pair of ganged contact arms 42 and 43 arranged to be selectively positioned in three positions representing the status of the rooms. When a guest or occupant of the room checks out, the switch 16 is placed in the first or OUT position and contact arm 42 engages contact 44 to connect DC. power through contact 45 and armature 46 of relay 41 to one end of red lamp 18 in the control console 10, one end of red lamp 49 in the remote console 20 and one end of red lamp 32 through diode 50 in the room unit 30. Diode 50, which is connected in series with lamp 32 is biased to block BC. when switch 16 is placed in the OUT position so as to prevent energization of lamp 32. The other ends of the red lamps 18, 49 and 32 are permanently connected to ground so that upon positioning of switch 16 in the OUT position, these lamps will be immediately energized to indicate to the staff, by the steady glow of the red light, that the room has been vacated and requires attention. The other contact arm 43 of switch 16 establishes a connection across contact 48 to electrically connect one end of green lamp 17, one end of the operating coil of relay 41, one end of green lamp 50 in the remote console 20 and contact 55 of switch 31 in the room unit 30. The other ends of the green lamp 17, operating coil of relay 41 and green lamp 50 are permanently connected to ground. Sin e switch 31 is open, that is, the maids key has not yet been inserted, relay 41 and green lamps 17 and 50 remain deenergized and in their off condition.

When a maid has been dispatched to a room that requires attention, the maid inserts the key 33 into the switch 31 thus establishing an electrical connection between movable contacts 55 and 57 and stationary or fixed contact 58 which is permanently connected to one terminal of the DC. source. Accordingly, all red and green lamps are now energized indicating the presence of the maid within the room. In addition, the operating coil of relay 41 is now connected across the DC. supply line through contact 55 of switch 31 and ground. Energization of relay 41 causes its armature 46 to switch to its other position and establish electrical connection with contact 47 which functions as a holding contact for relay 41 and supplies D.C. energization across the operating coil through contact arm 43 and contact 48 of switch 16.

When the maid has completed her work, the maid removes her key 33 from switch 31 which causes the red lamps to be extinguished, but leaves the green lamps in their energized condition. This condition results due to the transfer of armature 46 to its second position. While the maids key 33 was inserted into the switch 31, red lamps 18, 49 and 32 were energized through contacts 57 and 58 of switch 31; however, upon removal of the key 33, contacts 57 and 58 are opened, thus removing the energizing power from the contact terminals of the red lamps.

Upon registering a new guest in the room switch 16 is placed in its IN position. Contact arms 42 and 43 are centrally located between contacts 59 and 44, 60 and 48, respectively, thus returning relay 41 to its deenergized condition, deenergizing all lamps and restoring the system to a normal condition indicating that the room has been serviced and is presently occupied.

For indicating to a guest that a message has been received for the guest at the clerks desk, each room unit 30 is provided with the diode 50 which is connected in series with the red lamp 32. Switch 16 is selectively positioned in its third or MESSAGE position to establish electrical contact between contact arm 42 and contact 59 which is connected to a suitable A.C. supply. AC. power is thus provided to the ungrounded end of red lamp 32 at the room unit 30 through mechanical flasher 60 causing red lamp 32 to flash on and off. Red lamps 18 and 49 are also energized by the A.C. source to put the attendants on notice of the receipt of the message so that this information can also be relayed to the guest in the event the guest is not in the room. When the guest calls in to the clerks desk, switch 16 is returned to its IN position thus extinguishing all lamps and returning the system to its normal state.

In an alternate embodiment of the invention, provision is made for indicating at the control console and remote console 20 the rooms in which the maid is working to permit the housekeeper to supervise the quality of work. Accordingly, a resistor 61 is connected in circuit with the red lamp 32 of each room unit 30. When the maid enters the room, she inserts the key 33 into the switch 31 only halfway, thus establishing electrical contact between movable contact 55 and fixed contact 58 only. This causes the green light to be energized in the manner hereinbefcre described; however, the electrical circuit for the red lamps is completed through resistor 61 causing the red lights to burn only half-bright due to the reduced current flow. Upon completion of cleaning of the room, the maid pushes key 33 into switch 31 all the way. This serves to by-pass resistor 61 and complete the circuit for red lamps in the manner hereinbefore described causing red lamps to burn at full brightness. In this manner, the housekeeper as well as the front desk can tell exactly in which rooms the maids are presently working and the rooms which have been completed and left. The housekeeper may then inspect the rooms which have been completed, and upon finding them in a satisfactory condition, remove key 33 from switch 31, thus leaving only the green lamps 1'7 and energized.

The system has been described in connection with the operating circuits for one room; however, it should be readily apparent that the electrical circuits corresponding to each room are identical. The A.C. and DC. power sources, which may be a 12- or 24-volt A.C. and DC. source, are connected in parallel to similar contacts of the various switches for each room circuit. Each room unit 39 is interconnected by means of only one looping pair of conductors, one conductor connecting the ground side of red lamps and the other conductor connecting the fixed contacts of the key-operated switches.

From the foregoing description, it is apparent that there has been provided a highly efiicient and eifective sig nalling system for hotels, motels and like establishments which provides instantaneous room status indication at various locations and which can be used to signal a guest or occupant of the receipt of a message. Such a system lightens the burden of management and results in considerable economy due to savings in valuable time of operating personnel.

Although a particular embodiment of the subject invention has been described, many modifications may be made, and it is intended by the appended claims to cover all such modifications which fall within the true spirit and scope of the invention.

What is claimed is:

1. A hotel signalling system comprising a central panel, a remote panel, a plurality of room units, a source of A.C. current, a source of DC. current, each of said panels containing a plurality of pairs of lamps and each room unit containing a room lamp, each of said lamp pairs in one panel having a corresponding lamp pair in the other panel and a corresponding room lamp to form a plurality of individual signalling circuits, and each of said signalling circuits further including selector switch means having at least three positions and an output and connected to the source of A.C. current and the source of DC. current for selectively connecting said A.C. source of energization or said D.C. source of energization to said output or maintaining an open circuit condition between said sources and said output, a first lamp of each of said corresponding lamp pairs associated with the one signalling circuit connected to a first lamp energizing circuit, a second lamp of each of said same corresponding lamp pairs associated with the same one signalling circuit connected to a second lamp energizing circuit, first switch means connected to and operated in response to energization of said second lamp energizing circuit for opening a normally closed circuit between said selector switch means output and said first lamp energizing circuit, key switch means included in said room unit having at least three spaced contacts and responsive to the insertion of key means for shorting said contacts together, said first lamp energizing circuit connected to one of said contacts, said second lamp energizing circuit connected to another of said contacts, and the DC. source being connected to the remaining contact for energizing said lamp energizing circuits upon the shorting of said contacts.

2. A hotel signalling system as set forth in claim 1 wherein said selector switch means includes a normally open second switch means operative to close only in one of said selector switch means positions, said first switch means further including means responsive to energization of second lamp energizing circuit for closing a normally open circuit between the selector switch means output and a transfer contact for placing the source of energization present on the selector switch output upon the transfer contact, and a holding circuit connected between said transfer contact and said second lamp energizing circuit for maintaining said second lamp energizing circuit energized including in series said second switch means.

3. A hotel signalling system as set forth in claim 2 wherein said key switch means further includes a fourth spaced contact, a resistor connected across said one of said contacts and said fourth spaced contact of said key switch means for energizing said first lamp energizing circuit through said resistor upon partial insertion of said key means.

4. A hotel signalling system as set forth in claim 3 further including a flasher in series with the room lamp and the output of said selector switch means to cause said room lamp to be energized at intervals to provide a flashing signal when said A.C. source of energizat ion is connected to said output.

5. A hotel signalling system comprising a central panel, a remote panel, a plurality of room units, a source of AC. current, a source of DC. current, each of said panels containing a plurality of pairs of lamps and each room unit containing a room lamp, each of said lamp pairs and one panel having a corresponding lamp pair in the other panel and a corresponding room lamp to form a plurality of individual signalling circuits, and each of said signalling circuits further including selector switch means having at least three positions and an output and connected to the AC. current source and the DC. current source for selectively connecting the AC. current source of energization or the D.C. current source of energization to said output or maintaining an open circuit condition between said sources and said output, a first lamp of each of said corresponding pairs associated with the One signalling circuit connected to a first lamp energizing circuit, a second lamp of each of said lamp pairs connected to a second lamp energizing circuit, first switch means connected to and operated in response to energization of said second lamp energizing circuit for opening a normally closed circuit between said selector switch means output and said first lamp energizing circuit, said room lamp corresponding with said lamp pairs being connected to said first lamp energizing circuit through a diode in series therewith for preventing direct current from said DC. current source at said selector switch output from energizing said lamp and to allow energization of said lamp from said first lamp energizing circuit only by AC. current, key switch means included in said room unit having at least three spaced contacts and responsive to the insertion of a key means for shorting said contacts together, one contact of said key switch means connected to said room lamp at the portion of the series circuit between said room lamp and said diode for energizing both the room lamp and the first lamp energizing circuit, said second lamp energizing circuit connected to another of said contacts, and the DC. current source connected to the remaining contact for energizing said lamp circuits upon shorting of said contacts.

6. A hotel signalling system as set forth in claim 5 wherein said selector switch means includes a further noranally open second switch means operative to close only in one of said selector switch means positions, said first switch means further including means responsive to energization of said second lamp energizing circuit for closing a normally open circuit between the selector switch means output and a transfer contact for placing the source of energization present on the selector switch output upon the transfer contact, and a holding circuit connected between said transfer contact and said second lamp energizing circuit for maintaining said second lamp energizing circuit energized including in series said second switch means.

7. A hotel signalling system as set forth in claim 6 wherein said key switch means further includes a fourth spaced contact, a resistor connected across said one of said contacts and said fourth spaced contact of said key switch means for energizing said first lamp energizing circuit through said resistor upon partial insertion of said key means.

8. A hotel signalling system as set forth in claim 7 further including a flasher connected in series with the room lamp and the output of said selector switch means to cause said room lamp to be energized at intervals to provide a flashing signal when said A.C. source of energization is connected to said output.

References Cited by the Examiner UNITED STATES PATENTS 841,168 1/1907 Muschenheim. 998,391 7/1911 Powell. 1,327,837 1/ 1920 Muschenheim 340286 1,340,145 5/1920 Blair. 2,042,667 6/ 1936 Latzko. 2,980,890 4/ 1961 Staten 340-286 X NEIL C. READ, Primary Examiner.

Citas de patentes
Patente citada Fecha de presentación Fecha de publicación Solicitante Título
US841168 *8 Sep 190615 Ene 1907Frederick MuschenheimAnnunciator for hotel letter-boxes.
US998391 *4 Abr 191118 Jul 1911Edwin L PowellIndicator for hotels and other places.
US1327837 *12 Ene 191813 Ene 1920Blasdale Frederick WElectrical indicator
US1340145 *24 Jul 191918 May 1920BlairIndicating device
US2042667 *15 Mar 19302 Jun 1936Bbc Brown Boveri & CieLiving diagram
US2980890 *10 Mar 195918 Abr 1961Transvox CorpSignaling systems
Citada por
Patente citante Fecha de presentación Fecha de publicación Solicitante Título
US3353172 *9 Sep 196414 Nov 1967Call Boy Systems IncClock controlled hotel signalling system
US3594774 *31 Dic 196820 Jul 1971Dawson Herman LPlural module circuit signaling system
US3594784 *14 Abr 196920 Jul 1971Femminella John ACommercial laundromat signaling system
US3599199 *6 Dic 196810 Ago 1971Bunting Sterisystems IncSystem for simultaneously indicating a unit status at a plurality of stations
US3631536 *10 Jun 196828 Dic 1971Mosman John ARegister system memory modules
US3643222 *17 Ene 196915 Feb 1972Hitachi LtdRemote supervisory system
US3668682 *20 Nov 19706 Jun 1972Texas Oil Electric CoNurse call and alarm system for nursing homes and the like
US3732558 *9 Feb 19718 May 1973Headway CoHighway sign system
US3742141 *19 Oct 197026 Jun 1973Terra CorpHotel/motel room status system
US3754227 *27 Dic 197121 Ago 1973Andersson SHotel signalling system
US4194181 *28 Nov 197718 Mar 1980Efficiency Systems, Inc.Hotel room status monitor and power control system
US4254404 *13 Sep 19783 Mar 1981Kramor Industries Ltd.Paging and servicing system
US4378551 *5 Dic 198029 Mar 1983Motorola, Inc.Radio signal receiving apparatus with a security circuitry
US4758819 *7 Feb 198619 Jul 1988Aica Kogyo Co., Ltd.Keysensor
US5032834 *12 Feb 199016 Jul 1991Sara E. KaneStatus display system
US814910424 Jun 20093 Abr 2012David A CrumRoom management system
US20120242492 *25 Mar 201127 Sep 2012Tov 1 LLCSeat occupancy detection and display system
Clasificaciones
Clasificación de EE.UU.340/286.8, 340/313, 340/332, 340/4.6
Clasificación internacionalG08B5/36
Clasificación cooperativaG08B5/36
Clasificación europeaG08B5/36