Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
  • B63H—MARINE PROPULSION OR STEERING
  • B63H21/00—Use of propulsion power plant or units on vessels
  • B63H21/21—Control means for engine or transmission, specially adapted for use on marine vessels
  • B63H21/213—Levers or the like for controlling the engine or the transmission, e.g. single hand control levers

Definitions

• the invention relates generally to a control system for operating a propulsion system of a ship. This has at least one, but preferably two motors.
• adjustable clutches for forward and reverse driving a propeller shaft.
• a certain speed of the propeller shaft can be brought about either by varying the motor speed or the degree of slip of one of the clutches. To choose the direction of travel and
• Control station (main station), but preferably there are several control stations (main and secondary control stations).
• the control stations are arranged on the ship in such a way that from several existing ones
• control stations the most suitable can be selected as authorized to drive.
• control and sensor means are available. This can be electro-magnetic, for example
• Act 25 proportional actuators (control means) and, for example, optically acting speed sensors (sensor means).
• Propeller shaft are in driving connection.
• the drive group is assigned to three control devices (control means) for throttle servo, for gear shifting the gear (gear shift servo) and for actuating a control valve of a clutch (trolling valve servo).
• the control means listed are connected to an electronic control unit (CPU) via an electrical line connection. Another electrical connection exists between the control stations and the control unit.
• the propulsion system of a ship can be operated in such a way that an operating mode is selected from two possible operating modes.
• a first operating mode one of the clutches (forward or reverse travel) is completely closed.
• the driving speed is brought about by varying the engine speeds.
• an engine speed is maintained, while the speed of the ship is determined by the degree of slip of the clutches (trolling).
• Slip clutches for driving a ship for forward and reverse travel are known from DE-OS 21 20 639.
• a mode selection device in which a specific operating mode can be selected.
• the control lever of the control station is assigned a specific function.
• travel mode cruise control
• the clutch is closed for forward travel.
• the control lever is used to vary the engine speed to set a specific cruising speed.
• the mode selector the function assigned to the control lever changes. As long as this Mode is selected, the motor is operated at a certain, constant speed.
• Travel speed is varied via the control lever in such a way that the degree of slippage of the respective clutch of the transmission is chosen to be more or less large via the
• the degree of slip of the clutch thus varies the rotational speed of the propeller shaft.
• the known control system has control electronics to which an input and output unit, a display unit and control and sensor means are connected (see the Twin Disc “Twin Disc Power Commander” publication, imprint: 319MEC 5M-1-88).
• the control electronics consist of a main communication control unit and an auxiliary communication control unit.
• the port-side propulsion system is controlled via the main control unit, while the starboard-side propulsion system is monitored by the auxiliary control unit.
• the port-side control levers of the control stations main and secondary control station
• the starboard-side control levers of the control stations main and secondary control stations
• the main communication control unit is connected to the auxiliary communication control unit via line connections.
• the control and sensor means are each separately connected to the main control unit (port side) and the auxiliary control unit (starboard side) for ai «h.
• a mode selector and a display unit are assigned to each control lever.
• the known control systems which make it possible to operate a drive system using control electronics have the advantage that precise control of certain setpoints (for example the engine speed and propeller shaft speed) is possible.
• certain setpoints for example the engine speed and propeller shaft speed
• To connect a control station two connecting lines are required, which is the case when using, for example, a total of six control stations
• the present invention has for its object to improve a control system for operating a propulsion system of a ship of the type mentioned in such a way that the device-technical, electrical and electronic effort is kept smaller, that the operation is easier and the overall economy of the system is increased.
• the object on which the invention is based is achieved in that the propeller shaft speed and direction of rotation can first be set with the control lever. Since only the propeller shaft speed (with one direction of rotation) is set with the control lever, the operation of the control system is simplified in such a way that incorrect operation is impossible.
• Propeller shaft speed and direction of rotation is controlled by the control electronics - regardless of the operator - in such a way that certain operating parameters of the engine and / or the transmission are maintained.
• the operating parameters of the engine are primarily the speed, the fuel consumption, the measurable flue gas emissions, such as the NC share, or the soot concentration of the exhaust gases.
• the operating parameters of the gear unit to be observed are primarily the measured values from which the power loss of the gear unit can be determined.
• the control electronics define an operating state in which the operating parameters of the engine and / or the gearbox are the closest to the predetermined values (resulting from characteristic curves or characteristic maps). In the event of a possible operating state, the
• the control system allows an optimal one Operation of a drive system taking various aspects into account. For example, it is possible to operate the drive system in a manner that optimizes fuel consumption at certain engine speeds. At speeds at which, for example, the fuel consumption of the engine does not play a decisive role, the drive system can be operated so that the power loss of the transmission is particularly low. If, for example, there is a risk during operation that the engine is stalled or that, for example, exhaust gases with a high proportion of
• a plurality of control stations are connected to a data bus which is connected to the control electronics.
• the control stations are in communication with one another and with the control electronics through the proposed use of a bus system and thus over a single line.
• any number of control stations can be connected to this single line. It can be seen that the hardware expenditure required is reduced to a minimum. Thanks to the data transfer via the data bus, all information is available at any control station at any time.
• the control electronics consist of an electronic control device to which the control stations are connected via the data bus and the control and sensor means via connecting lines. Except for an electrical one
• the control unit advantageously contains a programmable memory for storing characteristic operating parameters for the operation of the engine and / or the transmission. These operating parameters can be, for example, limit speeds of the engine and the transmission, consumption values of the engine, exhaust emission values, pressure values (filter pressure, clutch pressure, lubricating oil pressure) etc.
• the programmability of the memory means that the values can be varied, which makes it much easier to match the drive system to different engine and transmission types or with regard to other specifications.
• two ranges of propeller shaft speeds can be made available within the swiveling range of the control lever. It is beneficial to select the first range so that it is smaller than the entire range of possible propeller shaft speeds. The second range extends up to the maximum possible propeller shaft speed. With the proposed measure there is a spreading of the travel path leading to
• Each of the control stations has an input and output unit with command buttons. There is also a display field to which dialing buttons are assigned. A specific function can be requested with one dial key each.
• buttons are designed as illuminated buttons.
• an optical assignment to the operating value shown in the display panel is established automatically. The operator is therefore always safely informed about the type and size of the displayed value.
• buttons indicate whether the displayed operating values are values of the motor or the gear unit.
• a light button can be provided to indicate impermissible deviations from operating values (alarm function), the size and location being defined by the current light combination.
• Propeller shaft speed is. This operating mode is set by pressing a dedicated command key on the input and output unit. It is particularly expedient to always display a speed proportional to the engine speed in the display field during this operation.
• the propeller shaft speed is maintained by the control electronics via the control and sensor means to a predetermined value. This takes place as a function of at least one characteristic value of the motor, a clutch remaining closed at all times or its degree of slip being regulated.
• the control electronics Since the engine speed is displayed during this operating mode, it is particularly advantageous for the control electronics to calculate an engine speed corresponding to the respective propeller shaft speed at propeller shaft speeds which - taking into account the gear ratio - are below the normal engine idling speed. This calculated engine speed or the propeller shaft speed is then displayed in the display.
• an operating state can be set which serves to warm up the engine.
• This operating state is selected by actuating a command key on the input and output unit.
• the prerequisite is that the control lever is in neutral position.
• the transmission remains in neutral.
• the engine speed can be changed using the control lever.
• the proposed control system can be completed by a further function, when selected, a transfer or takeover of the function of the starboard control lever to the port control lever is carried out by the control electronics.
• the drive system can only be controlled using the port control lever. The transfer takes place when the starboard control lever reaches or passes the position that corresponds to the position of the port control lever.
• the proposed control system for operating a drive system works with a data bus and at least one electronic control unit.
• the entire drive system can no longer be controlled. In this way, incorrect operation or misinterpretation or functions can be ruled out, which could possibly occur if the electronics only partially failed.
• at least the control station which is normally authorized to drive, has a control lever which is connected to the control means of the engine (throttle valve) and the transmission (couplings for forward and reverse travel) via cable pulls.
• FIG. 1 shows the basic structure of a control system for operating a drive system
• FIG. 2 shows an input and output unit
• Control station in a highly simplified, schematic top view
• Fig. 3 shows the arrangement of FIG. 1 with control and
• Fig. 1 is the basic structure of a
• the ship propulsion system is composed of a starboard propulsion system 1, which is summarized overall by the dash-dotted line, and a port-side propulsion system 2 (also combined with dash-dotted lines).
• a starboard propulsion system 1 which is summarized overall by the dash-dotted line
• a port-side propulsion system 2 also combined with dash-dotted lines.
• Each of the drive armatures 1 and 2 is structured as follows:
• An engine 3 for example a diesel engine, is drivingly connected to a transmission 4.
• the gear 4 can be flanged directly to the motor 3 or the drive can take place via an intermediate shaft 5, as in the present case.
• a transmission output shaft 6 is rotatably connected to a propeller shaft 7 which drives a propeller 8.
• the control system has a plurality of control stations, of which a main control station 9 and two secondary control stations 10 and 11 are shown and highlighted by dash-dotted lines.
• each of the control stations 9, 10 and 11 consists of a console 12 with a control lever 13 on the starboard side and a control lever 14 on the port side, based on the direction of travel of the ship.
• the console 12 is connected to an input and output unit 16 via a connecting line 15.
• At least the main control station 9 has an input arrangement 17 which is connected via a cable 18.
• the secondary control stations 10 and 11 do not have such an input arrangement 17, it would in principle be readily possible to embroider them with such a device.
• control stations 9, 10 and 11 are basically constructed in the same way, matching components are identified with the same reference numbers.
• the connecting lines 19 are omitted if the data bus 20 directly through the
• Control stations 9, 10 and 11 out (looped).
• the data bus establishes the (only) connection between the control stations 9, 10 and 11 to control electronics 21.
• the control electronics 21 in the illustrated embodiment are assembled from an electronic control unit 22 and a programmable memory 23 (EEPROM).
• the programmable memory 23 is used to store characteristic operating parameters for the operation of the motor 3 and / or the gear 4.
• Connecting lines 24 and 25 lead from the control electronics 21 to the drive system 1 and 2 (the purpose of FIG Connecting lines 24 and 25 will be explained in more detail below).
• a line 26 leads to the control electronics 21 and connects the control electronics 21 to the vehicle electrical system 27.
• the starboard control lever 13 and the port control lever 14 can be pivoted from the neutral position shown, in which they are approximately vertically directed, towards the bow (ahead) or towards the stern (aster) of the ship.
• the control lever 13 on the starboard side is assigned to the starboard propulsion system 1 and the port control lever 14 is assigned to the port propulsion system 2.
• the operator sets a propeller shaft speed and direction of rotation of the starboard or port side propeller shaft 7.
• the starboard propulsion system 1 is operated such that the propeller shaft 7 is driven in the forward direction and at a speed which is dependent on the pivoting position of the control lever 13.
• control station 9 is normally authorized to drive.
• Control station 9 or 10 or 11 whose control levers 13 and 14 specify the propeller shaft speeds are considered to be authorized to drive.
• the travel authorization which is normally at the main control station 9, can be transferred to one of the secondary control stations 10 or 11 and vice versa (station transfer). The conditions under which this is possible are explained below.
• the position of the control levers 13 and 14 has at least up to a preselected propeller shaft speed no influence on the speed of the propeller shafts 7.
• the position of the control levers 13 and 14 has at least up to a preselected propeller shaft speed no influence on the speed of the propeller shafts 7.
• Propeller shaft speed by the control electronics 21 to a predeterminable minimum value depending on at least one characteristic value of the motor, which is preferably the motor speed.
• an input and output unit 16 is an essential part of a control station. This applies both to the main control station 9 and to the secondary control stations 10, 11 and further secondary control stations (not shown). 2 shows details of the design of an input and output unit 16. The connecting lines 15 and 19 and the cable 18 are connected to the input and output unit 16.
• the input and output unit 16 has a number of command keys 28, 29, 30, 31, 32, 33 and 34. It is expedient to design the command keys 28 to 34 as illuminated keys, since the switched function is optically assigned to the operator of the current display by an illuminated key.
• Command key 28 This command key defines the driving authorization of a control station. Pressing the command key 28 signals that the drive authorization (which is normally located at the main control station 9) is to be transferred or taken over. If the command key 28 of a (still) authorized station is actuated, this key, which is designed as a light key, starts to flash. At the other stations not authorized to drive, the command buttons 28 and the buttons 29 or 30 or 31 or 32 start to flash. This shows the takeover option by a station and the state of the ship. If the command is now to be taken over at a control station, the key 28 must be pressed. The flashing light of the illuminated button 28 changes to permanent light and the current speeds are displayed.
• control levers 13 and 14 then have to be transferred to a position which corresponds to the position of the control levers 13 and 14 of the station previously authorized to drive. Only when this requirement is met is acceptance of the travel authorization acknowledged. This is done in such a way that the key that indicates the ship's driving status is constantly lit, while the analog keys of the other control stations go out.
• Command key 29 As already mentioned at the beginning, each of the control levers 13 and 14 is only available for the selection of the rotational speed of the propeller shaft 7 and 14 a limited swivel angle in the forward direction or reverse direction. However, this means that the sensitivity with which adjustment operations can be carried out is not always sufficiently high, as is desired per se.
• a certain range can be selected from the range of possible propeller shaft speeds from zero revolutions per minute to a maximum revolution per minute.
• This particular range of possible propeller shaft speeds is smaller than the entire range of possible propeller shaft speeds. Assuming that the range is more possible
• Propeller shaft speeds ranging from zero revolutions per minute to 6,000 revolutions per minute can be selected by pressing the command key 29, for example, a speed range from zero revolutions per minute to 2,000 revolutions per minute. For this speed range, the entire swivel path of the control levers 13 and 14 is then available for setting purposes. For practical needs, it may be sufficient to select only one speed range when driving forward. However, it is also possible to also provide the measure described for the reverse driving range. In other words, when the command key 29 is pressed, the lower speed range is spread out so as to increase the sensitivity of the setting. However, the same goal can also be achieved in a purely mechanical way.
• Command key 30 By pressing command key 30, the entire range of possible propeller shaft speeds is assigned to the swivel path of control levers 13 and 14. The ranges of possible propeller shaft speeds can also be coordinated such that the command key 29 is assigned a lower and the command key 30 the - subsequent - upper speed range.
• Command key 31 Preferably the function of the starboard side
• Control lever 13 can be transferred to the port-side control lever 14 by the control electronics, so that the control of the propulsion systems 1 and 2 takes place exclusively via the port-side control lever 14 (synchronous operation).
• This function is selected by pressing the command key 31.
• This button then flashes. The transfer is carried out automatically when the starboard control lever reaches or passes the position that corresponds to the position of the port control lever. The flashing light then goes on
• Command key 32 With the command key 32 an operating mode "Docking" of the drive system can be selected. In this operating mode, the position of the control levers 13 and / or 14 is at least up to a preselected propeller shaft speed without influencing the speed of the propeller shaft 7. The speed of both propeller shafts is regulated by the control electronics 21 to a predeterminable value.
• Command key 33 can be used to lower the predeterminable value of the propeller shaft speed (compare what was said above).
• Command key 34 By pressing the command key 34, the predeterminable value of the propeller shaft speed can be increased.
• the display field always shows a speed analogous to the engine speed. If the propeller shaft speed falls below the usual engine idling speed - taking into account the gear ratio - the control electronics calculate a corresponding, theoretical engine speed and display this in the display panel.
• the operating mode "docking" is left in the neutral position of the control levers 13, 14 by pressing another command key 29 or 30 or 31.
• the last set propeller shaft speed is stored in the memory 23 and automatically set again when this operating mode is called up again.
• At least the main control station 9 has an input arrangement 17.
• a further command button 35 is provided here, with which an operating state can be controlled which serves to warm up both motors 3.
• the control electronics 21 ensure that the gears 4 remain switched to the neutral position.
• the engine speed can be changed using the control levers 13 and 14 become.
• This operating state is exited when one of the remaining command keys 28 to 34 of the input and output unit 16 is actuated, the control levers 13 and 14 having to be in the neutral position.
• Each input and output unit 16 has numerical display fields 36 and 37.
• the display panel 36 is assigned to the port-side propulsion system 2 and the display panel 37 to the starboard-side propulsion system 1. They are preferably LCD displays.
• Dial keys 38, 39, 40 and 41 and 42, 43, 44 and 45 are grouped around display fields 36 and 37. Two further dial keys 46 and 47 are connected to the lower longitudinal side of display field 37. All dial keys 38 to 47 are designed as illuminated keys.
• a light button 48 is connected to the upper long side of the display panel 37. This button lights up when there are impermissible deviations in certain operating parameters of the motors 3 and / or the gearbox 4 (alarm function). This button is used to acknowledge the alarm or to advance the display if several alarms are active at the same time.
• dialing keys Since the arrangement of the dialing keys which are assigned to the display field 36 is carried out in an analogous manner, these dialing keys are provided with the same reference numbers.
• the selector buttons are assigned the following operating parameters, which relate to the starboard propulsion system 1:
• Select key 38 revolution of the motor 3 per minute;
• Select button 39 cooling water temperature of the motor in ° C or ° F;
• - Selection button 40 lubricating oil pressure of engine 3 in bar or psi;
• Dial button 41 charging voltage in volts.
• Select button 42 speed of the propeller shaft 7 per minute
• Select button 43 temperature of the gear 4 in ° C or ° F;
• Selector button 44 clutch pressure in bar or psi and - selector button 45: filter pressure in bar or psi.
• dial keys 38 to 47 in interaction with the display fields 36 and 37 will be explained using two examples:
• the selection button 41 assigned to the display field 36 is pressed. This button lights up. The level of the charging voltage is shown numerically in the display field. Since it is a characteristic value of the motor, the selection button 46 assigned to the display field 36 also lights up.
• the selection key 42 assigned to the display field 37 is actuated.
• the key begins to light up and the display shows the number numerically Number of revolutions per minute is displayed. Since it is a characteristic value of the transmission, the dial button 47 also lights up.
• the input and output unit 16 is also equipped with a horn 49 with which an acoustic alarm can be given.
• the input arrangement has further illuminated keys 50, 51 and 52. Their functions are as follows:
• the control electronics make certain state data available.
• This state data can be displayed in the display fields 36 and 37.
• the display of the status data is selected by pressing the light button 50 and the light buttons 46 or 47, via which
• Command keys 33 and 34 can be set a specific code number.
• Illuminated key 51 By actuating the illuminated key 51, the status data which were set via the above-described selection of the code number are displayed or the parameter values set are programmed.
• the Ein ⁇ tellung or programming of the control electronics eif ⁇ gL by pressing the illuminated push-button 50 on the keys 33 and 34 is set to a specific code number in the display field 36 or 37 and acknowledged by operating the illumination key 51st
• the control electronics 21 is now in the programming mode and does not allow driving more to.
• the operating parameters or setting values are entered in programming mode in the manner described. Each operating parameter is assigned its own code number (identifier).
• FIG. 3 The diagram of the control system for operating the propulsion systems 1 and 2 shown in FIG. 3 essentially corresponds to that according to FIG. 1.
• the existing control and sensor means of the starboard propulsion system 1 are now explained on the basis of these diagrams. Since the control and sensor means for the port-side propulsion system 2 are designed to match, the same reference numerals are used for corresponding components.
• control stations 9, 10 and 11 are connected to the data bus 20 via the connecting lines 19.
• the data bus is connected to the control electronics 21. From the control electronics 21, connecting lines 24 and 25 lead to the drive system 1 and to the drive system 2. More precisely, the connecting line 24 leads to control and sensor means 53 (indicated overall by the dash-dotted outline) of the motor 3 and to control and sensor means 54 (also summarized by the dash-dotted outline) of the transmission 4.
• the control and sensor means 53 of the motor 3 are composed as follows:
• a connecting line 55 leads from the connecting line 24 to a temperature sensor 56 which monitors the temperature of the cooling water, to a pressure sensor 57 for measuring the lubricating oil pressure and to a converter 58 which converts digital input signals into analog electrical output signals.
• the converter 58 is connected to an actuator 59 of the motor 3.
• Actuator 59 serves to adjust the component which is provided for the fuel supply to the engine 3. This can be, for example, a throttle valve or the delivery rate regulator of an injection pump of a diesel engine.
• the speed of the motor 3 is detected with the aid of a speed sensor 60.
• the design of the sensors used is not restricted to a specific type.
• the speed sensor 60 can act, for example, optically, magnetically or inductively.
• control and sensor means of the motor consisting of the temperature sensor 56, the pressure sensor 57, the converter 58 and actuator 59 and the speed sensor 60, they are characteristic
• the position of the throttle valve or the delivery rate regulator of the injection pump of a diesel engine, in conjunction with the speed of the engine, is a measure of the fuel consumption. The remaining values allow further conclusions to be drawn about the system status.
• the recorded characteristic operating parameters are continuously communicated to the control electronics 21.
• the control and sensor means of the gearbox 4 are constructed as follows:
• a temperature sensor 61 measures the temperature of the transmission (by measuring the temperature of the oil filling).
• a pressure sensor 62 is used to detect the clutch pressure.
• Another pressure sensor 63 detects the filter pressure.
• a converter 64 interacts with a clutch pressure regulator 65. The converter 64 converts digital signals into analog electrical output signals. In this way, the clutch pressure actuator 65 is adjusted so that the clutch pressure can be varied. The consequence of this is a different degree of slip of the oil-hydraulic actuatable clutches for forward and reverse travel.
• a converter 66 is assigned to a clutch 67 for forward travel. As already mentioned, the clutch 67 is constructed as a multi-plate clutch and can be actuated oil-hydraulically. The coupling can be opened or completely closed. Due to the controllability of the clutch pressure, the degree of slip can be varied as desired, so that, for example, the speed of the propeller shaft 7 can fall far short of the engine speed - also taking into account the transmission ratio of the gear 4.
• a converter 68 is used to actuate a clutch 69 for reverse travel.
• the control and sensor means of the transmission 4 are completed by a speed sensor 70 with which the speed of the propeller shaft 7 is detected.
• the sensors used moreover, it applies that they are not restricted to a specific type. The person skilled in the art can select suitable sensors from the large number of possible types.
• the control and sensor means 54 of the transmission 4 consisting of the temperature sensor 61, the pressure sensors 62 and 63, the converter 64 and clutch pressure plate 65, the converter 66 and the clutch 67 for forward travel, the converter 68 and the clutch 69 for the Reverse travel and the speed sensor 70 for detecting the speed of the propeller shaft 7, characteristic operating parameters of the transmission 4 can be detected or changed.
• These characteristic operating parameters include, for example, the input and output speed of the transmission, the power loss of the transmission and the level of the clutch pressure. From the characteristic operating parameters, important conclusions can be drawn about the system state of the transmission 4. The recorded operating parameters are continuously communicated to the control electronics 21.
• the characteristic operating parameters of the motor 3 and the transmission 4 communicated to the control electronics 21 are predetermined by the latter.
• the operating parameters of the motor 3 and the transmission 4 can be linked to one another in order to be able to draw conclusions about the system state of the drive systems 1 and 2.
• the control system described for operating the propulsion systems 1 and 2 is equipped with an emergency control in order to be able to control the ship to at least a limited extent if the electronics fail.
• an emergency control in order to be able to control the ship to at least a limited extent if the electronics fail.
• control electronics 21 With the control levers 13 and 14, the operator adjusts the speeds of the propeller shafts 7.
• the set speed is regulated in a special way by the control electronics 21:
• control electronics 21 freely define an operating state without any influence on the part of the operator. This can either correspond to an operating state in which the speed of the propeller shaft 7 is brought about by changing the speed of the motor 3 when the clutch 67 or 69 is closed. However, the control electronics 21 can also bring about an operating state in which the speed of the propeller shaft 7 is brought about at a predetermined speed of the motor 3 by changing the degree of slip of the clutch 67 or 69. The control electronics 21 selects and determines the operating state in which the
• a transition area plays a role, which is characterized by the fact that the coupling 67 or 69 is maintained. In this transition area, the coupling (67 or 69) is in the zone between a slipping and a closed state. Under these circumstances, the clutch tends to rattle (slip stick), which besides the jerky opening and closing especially through pounding noises. In order to eliminate this undesired behavior, it can be advantageous to leave the clutches 67 and 69 open in this transition region with a constant degree of slip and to increase the engine speed.

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• 1991
  • 1991-04-12 WO PCT/EP1991/000702 patent/WO1991016235A2/de active IP Right Grant
  • 1991-04-12 DE DE59107968T patent/DE59107968D1/de not_active Expired - Lifetime
  • 1991-04-12 EP EP91907418A patent/EP0524992B1/de not_active Expired - Lifetime
• 1992
  • 1992-10-13 US US07/937,903 patent/US5336120A/en not_active Expired - Lifetime

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