WO1999057794A1

WO1999057794A1 - Station for recharging and automatic identification of plural types of batteries

Info

Publication number: WO1999057794A1
Application number: PCT/IT1998/000126
Authority: WO
Inventors: Mauro Paganini; Giorgio Paganini
Original assignee: P.M.G. S.N.C. Dei F.Lli Paganini Mauro E Giorgio
Priority date: 1998-04-30
Filing date: 1998-05-20
Publication date: 1999-11-11
Also published as: TW412877B; ITMI980929A1; IT1305609B1; AU7547798A; EP1075725A1

Abstract

Station (10) for recharging the batteries (70-72) used in portable electric tools, having one or more slots (31) each comprising a cavity (34), flush with the upper surface (32) of the station (10), for couplings (73) on the batteries (70-72), means consisting of electric contacts for said couplings and of microswitches inside the cavities (34) close to the electric contacts, manually operated keys, electronic cards with a microprocessor for identification of a battery's specific technology and of the rated voltage of the batteries (70-72) especially those of nickel-cadmium (70) and of nickel-metal-hydride (72) and for implementation, including a check on all necessary parameters, of optimum sequences of discharge, recharge and maintenance, specific to the technology of the battery (70-72) connected up.

Description

STATION FOR RECHARGING AND AUTOMATIC IDENTIFICATION OF

PLURAL TYPES OF BATTERIES

10

15 The invention concerns recharging of batteries used in portable electric tools generally.

At present the use of portable electric tools such as drills, screwers and many others is often hindered by problems arising from the variety of batteries available as well as by the difficulty of correctly recharging them

20 with due respect for times needed and of checking the batteries being recharged from one moment to the next bearing in mind the specific characteristics of the various brands on the market. The above invention eliminates or considerably lessens these difficulties, offering other important advantages besides as will now be explained.

25 Subject of the invention is a unit for recharging the various brands of batteries on sale for use with portable electric tools, such as nickel- cadmium, nickel-metal-hydride batteries, and others. This station presents one or more battery slots, substantially the same, each comprising a cavity, flush with a plate matching with the upper

30 surface of the station, that contains plugs for electrical connection to the battery to be recharged and comprising means associated to an electronic card connected to a microprocessor with which to identify the specific technical features and voltage rating of the battery, especially of nickel-cadmium and nickel-metal-hydride batteries, checking on all the necessary parameters for execution of an optimum sequence of discharge, recharge and maintenance, specific to the technology of the battery connected up. The means associated to the electronic card are electric contacts placed inside the cavity, to match with the electric contacts on practically all the batteries on the market, and microswitches placed inside the cavity to fit with the raised contacts on most of the batteries available, close to said electric contacts, for automatic identification of the specific technology and voltage rating of the battery when it is placed in position in a slot.

In one type of execution the means associated to the electronic card are keys, manual selectors and the like.

The electronic card, connected to a microprocessor, comprises circuits for identification of the technical features and voltage rating of the battery to be recharged, through information received from means such as the electric contacts in the slot and on the battery, such as the microswitches in the slot at the position of teeth on the battery connections or from information received following use of the selector and manual keys placed in the slots, and comprises discharge and recharge circuits automatically adjusted to the type of battery, this being done by microprocessors on receipt of the above information.

The microprocessor comprises software parts each programmed to handle the recharging process of a specific battery. Each program: - stores all parameters for optimum charge of a certain battery, such as discharge current, charge current, maintenance current, minimum discharge-charge switching voltage, maximum battery voltage, maximum charge time, minimum and maximum discharge temperatures, minimum and maximum charge temperatures, value of the slope of the charging curve, charging at constant current and at variable current, charging at constant voltage; - controls, from one moment to the next, values noted on the battery during charge with those programmed for a battery of the same type, so that recharging is done correctly and without damaging the battery;

- breaks the sequence if parameters are not observed due to a fault in the battery, and signals the fault and the break in sequence.

The microprocessors in the cards present at the various slots are connected to a card with visualization circuits that:

- visually process the data from the microprocessors, process all para- rmeters related to discharge and to charge of each battery connected;

- process messages concerning the type of battery inserted, instantaneous voltage of the battery, discharge current, charge current, main- tenance current, battery temperature, total time from start of sequence, time from start of charging sequence, battery capacity, battery whose charge current is suspended, run down battery, high temperature, short- circuited battery cells;

- process messages telling the operator what to do to extract a battery, discard a battery, allow a battery to continue.

The above explains how the state of the sequence of each battery being charged can be seen from one moment to the next. When a battery to be charged is connected up, the discharge sequence starts automatically and continues until the minimum value of voltage set is reached; this permits the memory effect to be cancelled.

The electronic cards can be for discharging and charging but also for discharging only.

By proportionally adjusting current, the microprocessor checks that electric power does not exceed the maximum dissipatable threshold on the dissipator, fixed to the electronic card, to prevent overheating of the electronic circuits and of the internal structure of the station. During the charging stage the microprocessor constantly reports electric power, real performance of the circuit and real energy storage capacity by the battery connected up, thus permitting the user to evaluate the extent of battery wear and arrange for its replacement or recharge.

The electronic circuits can advantageously comprise an interface for a personal computer.

In one preferable type of execution the station is associated to others substantially the same so as to form a set of battery charging stations, connected to a computer to analyse statistics, trace diagrams and check on the overall state of the stations for their more efficient management. Data processed by the data-visualizing circuit are put onto a display. In a preferred type of execution said data are also sent to a printer.

In one type of execution data processed by the data visualizing circuit are sent to a personal computer.

If, at the end of a charging sequence, a battery put in for charging does not reach the minimum capacity that makes its continued use worthwhile, the visualizing circuit puts out a "battery exhausted" message together with the numerical value of said battery's capacity, so that the owner can decide if the time has come to replace it.

The statiion here described comprises a ventilation system to carry off heat generated by internal electronic circuits, and an internal thermostat which, if internal temperature exceeds the set value, turns off the charge circuit until the temperature returns to the accepted level. In a preferred type of execution there are slots for ten batteries. The invention offers evident advantages. Several batteries can be charged simultaneously, with automatic identifi- cation of their techncology, especially that of nickel-cadmium batteries and of nickel-metal-hydride batteries.

Identification of battery technology enables the microprocessors, installed on the electronic circuits of the charging station, to select all the parameters required for an optimum sequence of discharge, charge and maintenance as all such parameters needed for charging the various types of battery are recorded in said microprocessors. The central microprocessor can therefore supervise progress of the discharge and charge sequences of the battery put in, comparing it with the sample data stored. Automatic identification of any anomalies that may occur during the stages of discharge and charge, and despatch of related data to a display, printer or personal computer facilitates checking by the user. As discharge down to the minimum programmed voltage value, with can- cellation of memory, is done automatically when the battery is put in, the user can always have fully charged batteries available, with a capacity substantially the same as nominal.

The presence of a circuit that makes a proportional adjustment of current, preventing the maximum power available from being exceeded, ensures of the electronic circuits against overheating.

The presence in the charging station of circuits that measure the real storage capacity of energy by the battery put in, with transmission of related data to the display, enables the user to detect the extent of wear in the battery and to replace or recharge it as the case may be.

As several stations can be connected to a computer for real time knowledge of the state of a stock of batteries, firms can make far better use of their batteries than was possible before. Use of a printer to make printouts of data provides battery makers with documentary evidence of exhausted batteries that need replacement.

The described invention makes possible execution of a fully automatic and optimum sequence of discharging-charging and maintenance for any type of battery with visualization and documentation, from one moment to the next, of all data related to said sequence, and with indication of any anomalies, faults and other details needed for efficient management of a stock of batteries.

All this greatly increases efficiency, cuts down wasted time, reducing wear on batteries to the great benefit of users who need only connect up a battery periodically into the charging station to read data about its con- dition on a display, on a printout or even on a computer,

Characteristics and purposes of the disclosure will be made still clearer by the following example of its execution illustrated by diagrammatically drawn figures. Fig. 1 Battery discharge-recharge station, subject of the invention, for portable electric tools providing ten slots, and a device for visualizing the working parameters, with three batteries respectively of nickel-cadmium, nickel-metal-hydride and another type, being charged, perspective view. Fig. 2 The above station with door and lid opened. Fig. 3 Detail of one slot, front view, partially cut away.

Fig. 4 As above, with a nickel-cadmium battery being put in, side view.

Fig. 5 As above, plan view.

Fig. 6 Electric wiring diagram. Fig. 7 Electronic diagram for the discharge-charge cards.

Fig. 8 Electronic diagram for the visualizing card.

Fig. 9 Flow diagram for nickel-cadmium batteries.

Fig.10 As above, for nickel-metal-hydride batteries.

The station 10 shaped like a box 1 1 , with lid 12, front door 13 and four feet 17 has ten slots 31 on its top surface 30 for recharging batteries like

70-72 these being of nickel-cadmium, nickel-metal-hydride and of another type respectively.

The lid 12, fixed on by rear hinges 14, has a handle 15 and lateral struts

16 to hold the open lid up and free the hands to move the batteries; the lid can be closed by a lock not shown in the drawing.

Each slot 31 comprises an upper plate 32, with LEDs 47-49, the body 33, a substantially oval cavity 34,with channel 40 on one side to carry battery connections, like 73, contacts 35-38 and two microswitches 41 , 42.

Connections, such as 73, are oblong, of a constant rectangular cross section with curved shorter sides; they have electric contacts on the longer and shorter sides and lateral central rectangular ribs that stop short of windows, like 79, to give access to the electric contacts.

The ribs may be extended, according to the type of battery, to form one or two lateral teeth to permit identification of the battery. In Figs 3-5 the battery 70 is a nickel-cadmium 12-volt battery; its electric contacts 74, 75, 76 can be seen on one side at the end of a cental rib 77.

Said rib extends to become a tooth 78 at the side of contact 76.

The visualizing device 50 is placed on the top surface; it has a display 51 and button switches 52, 53 for the functions of "selection and position". The useful indications shown on the display include, in particular:

- 55 position number

- 56 battery voltage

- 57 discharge, charge or maintenance current - 58 battery temperature

- 59 time passed since the start of the operation

- 60 charging time

Devices placed on the door 13 include the voltage-on indicator 18 with internal thermostat 24, the high temperature indicator 19 and knob 20, to close the door, said knob being mechanically connected to the internal switch 29 to switch off current automatically when the door opens.

Inside the structure is a fan 25 close to the grating 26, an automatic switch 27 and thermostat 24. Centrally inside the structure are horizontal racks 80 to receive ten discharge-charge cards 120 and a data visualizing card 125.

Lower down is the power transformer 85, the transformer 86 and distribution terminals 87 with contactor, for an auxiliary circuit.

Fig. 6 shows the electric wiring diagram to supply current, through line 100 and the local mains network, to the transformer 85 preceded by the protective circuit 84.

Through the wires 1 10-112, electric current is supplied to the discharge and charge cards, like 120, preceded by the protective circuit 88.

Through wires 1 13, current is carried from said discharge-charge cards to the contacts in the slots 31 .

As seen in Figs 6-8, various types of batteries, including nickel-cadmium

70, nickel-metal-hydride 71 and other types of batteries 72 can be placed in said slots.

Through wire 115 electricity is carried to the data visualizing card 125 preceded by the protective circuit 90, and also feeds the display 50, the printer 65 and, through wire 114, the voltage-on indicator 18 and the cooling fan 25 preceded by the protective circuit 91.

Fig. 7 ilustrates the electronic diagram concerning two slots from among the ten in the charging station 10. The disicharge and charge cards 120 can be seen, connected to the slots 31 comprising the electronic temperature sensor 21 .

These cards comprise the following circuits:

- 130 temperature control with the electronic sensor 8

- 131 identification of the type of battery put into the slot - 132 identification of battery voltage connected up - 133 discharge adjusted to the type of battery - 134 charge adjusted to the type of battery - 135 temperature control through resistive sensor inside the battery

All these circuits are connected, in each card, to a microprocessor 140 for checking and execution, this in turn being connected to the LEDs 47-49 that indicate the state of battery sequence. The microprocessor 140 comprises a variety of software each part of which is suited to recharge of a specific battery, with prior storage of all parameters required for the best possible charge for a specific battery, such as discharge current, charge current, maintenance current, minimum change of voltage from discharge to charge, maximum voltage for the battery, maximim charge time, minimum and maximum discharge temperatures, minimum and maximum charge temperatures, value of the slope of charge curve, charge at a constant current, charge at a variable voltage, charge at a constant voltage, and checks from one moment to the next that values found in the battery during charge are the same as those programmed for a battery of the same type, also ensures that recharging is done correctly and without damaging the battery and stops the sequence if parameters are not observed due to some fault in the battery, then giving a warning of the fault and of stoppage. Acting on information received automatically when inserting the nickel- cadmium battery 70, from contacts 35-38 in the slot 31 , matching with the battery's contacts 74-76, and from closure of the microswitches 41 , 42 caused by the tooth 78 on the battery's connection 73, or due to action of a manually operated key 138 (see Fig. 7), the circuits 131 and 132 of each card 120 identify the type and voltage of the battery and transmit the information received from the microswitch 140 which operates the software for the battery put in and is therefore suited to recharging it.

Connections to the data visualizing card 125 are effected by the microprocessors of the various discharge-charge cards 120 through wires 111 and 1 15 as shown in Figure 8. 9

Said card 125 comprises the data transmission serial circuit 150 that connects with the main microprocessor 151 for processing all the characteristic parameters of the batteries being charged. This microprocessor 151 is connected to the devices already mentioned, such as the display 50, printer 65, keyboard 66 and RS 485 serial circuits 67 for connection to a first external computer and RS 232 serial 68 for connection to a second external computer. Figures 9 and 10 illustrate the two flow diagrams for nickel-cadmium and nickel-metal-hydride batteries respectively. All phenomena are clearly indicated in the squares.

Connections between the two diagrams shown in the two Figures are made clear by means of numbers marked on wires 155-158 common to both diagrams.

Claims

1 0Claims

1 . Recharging station (10) for various types of batteries (70-72) on the market, for portable electric tools, such as nickel-cadmium, nickel-metal- hydride batteries and others, characterized in that they have one or more substantially equal slots (31) each comprising a cavity (34) flush with a plate (32) matching with the upper surface (30) of the station (10) for insertion of couplings (73) with electric connections (74-76), of the battery (70-72) to be recharged and comprising means (35-38, 41 , 42, 138) associated to an electronic card (120) connected to a microprocessor (140), able to identify the specific technology and voltage rating of the battery (70-72), especially of nickel- cadmium (70) and nickel-metal-hydride (71 ) batteries and, by checking all the necessary parameters, operate the optimum sequences for discharge, charge and maintenance specific to the technology of the battery (70-72) connected up.

2. Station (10) as in claim 1 , characterized in that the means associated to the electronic card (120) are the electric contacts (35-38) placed inside the cavity (34) to match with the electric contacts (74-76) of the couplings (73) of substantially all batteries (70-72) on the market for the purpose of identifying the specific technology and voltage rating of the battery, when connection of couplings (73) of the battery (70-72) is automatically made.

3. Station (10) as in claim 1 , characterized in that the means associated to the electronic card (120) are microswitches (41 , 42) placed inside the cavity (34) at the raised ribs (77) on the couplings (73) of most types of battery (70-72) on the market, close to the electric contacts (38, 76), for automatic identification of the specific technology and of the rated voltage of the battery (70-72) at the moment when the couplings (73) of the battery (70-72) are connected.

4. Station (10) as in claim 1 , characterized in that the means associated to the electronic card (120) are electric contacts (35-38) placed inside the cavity (34) to match with all the electric contacts (74-76) on the couplings (73) of most types of 1 1

battery (70-72) on the market, and microswitches (41-42) placed inside the cavity (34) at the raised ribs (78) on the couplings (73) of most types of battery (70-72) on the market, close to said electric contacts (76), for automatic identification of the specific technology and of the rated voltage of the battery (70) when the battery (70-72) is connected.

5. Station (10) as in claim 1 , characterized in that the means associated to the electronic card (120) are keys (138), manual selectors (27) and the like.

6. Station (10) as in claims 1 to 5, characterized in that the electronic card (120) connected to a microprocessor (140) comprises circuits (131 -132) for identification of the specific technology and of the rated voltage of the battery (70-72) connected up, following information received from means such as the electric contacts (35-38, 74-76) placed in the slots (31) and in the battery (70-72), such as microswitches (41 , 42) placed in the slots (31) close to the teeth (78) on the couplings (73) of the battery (70) or received as a consequence of the use of keys (138), manual selectors and the like placed in the slot (31), and comprises discharge (133) and charge (134) circuits automatically adjusted to the type of battery (70-72) connected up, this being done by the microprocessor (140) on receiving said information.

7. Station (10) as in claim 1 , characterized in that the microprocessor (140) comprises a variety of software each piece programmed to implement recharge of a specific battery (70-72) with prior storage of all parameters required for optimum charge of a specific battery (70-72), such as discharge current, charge current, maintenance current, minimum change of voltage from discharge to charge, maximum battery voltage, maximum charge time, minimum and maximum discharge temperatures, minimum and maximum charge temperatures, value of the slope of the charge curve, charge at constant current, charge at variable current, charge at constant voltage, checking moment by moment, by means of specific circuits (133-134), equivalence between values found on the battery (70-72) during charge and those set for a battery of the same type so that recharge is done correctly and 12

without damaging the battery (70-72) and suspending the sequence if parameters are not observed due to failure in the battery (70-72), giving indication of the failure and of sequence suspension.

8. Station (10) as in claim 1 , characterized in that all the microprocessors (140) for the cards (120), each in its slot (31), are connected to a card (125) with data visualizing circuits (151) that visually process data from the microprocessors (140), especially all parameters concerning discharge and charge of each battery (70-72) connected, that process messages about the type of battery (70-72) connected, instantaneous voltage (56) of the battery, discharge current (57), charge current (57), maintenance current, battery temperature (58), total time from start of sequence (59), time from start of charge sequence, value of battery capacity, run down battery, exhausted battery, high temperature, short-circuted battery cells, and that process messages telling the operator what to do for extracting a battery, for eliminating a battery, for allowing it to continue, and so on, permitting constant visualization (51) of the state of the sequences of batteries (70- 72) being charged.

9. Station (10) as in claim 1 , characterized in that as soon as a battery (70-72) is connected up for charging, the discharge sequence is automatically started and continued to the minimum programmed value of voltage so that anything stored is cancelled.

10. Station (10) as in claim 1 , characterized in that the electronic cards (120, 125) are for discharge and charge.

1 1 . Station (10) as in claim 1 , characterized in that the electronic cards (120, 125) can be for discharge only.

12. Station (10) as in claim 1 , characterized in that the microprocessor (140) adjusts current proportionately, in that electric power does not exceed the maximum threshold that can be dissipated on the dissipator fixed to the electronic card (88) for 13

protection of electric circuits and of the inside of the structure (11) of the station (10) against excessive overheating.

13. Station (10) as in claim 1 characterized in that, during charging, the microprocessors (140, 151) keep a constant check on electric power, on real performance of the sequence and on real capacity for storing energy by the battery (70-72) connected up, thus also permitting the user to decide on the state of wear of the battery and whether it is to be discharged or recharged.

14. Station (10) as in claim 1 , characterized in that the electronic circuits comprise an interface (67, 68) for a personal computer.

15. Station (10) as in claim 1 , characterized in that it is associated to others substantially the same to form a complex of battery charging stations, connected to a personal computer so that in real time statistics can be analysed, diagrams drawn and the state of the entire complex known for its most efficient overall management.

16. Station (10) as in claims 1 and 8, characterized in that data processed by the data visualizing circuits (125) are shown on a display (50).

17. Station (10) as in claims 1 and 8, characterized in that data processed by the data visualizing circuits (125) are passed on to a printer (65).

18. Station (10) as in claims 1 and 8, characterized in that data processed by the data visualizing circuits (125) are sent on to a personal computer.

19. Station (10) as in claims 1 and 8, characterized in that if, at the end of a charging sequence, a connected battery (70-72) does not reach the minimum value of capacity to make worthwhile its continued use, the data visualizing circuit (125) processes an "exhausted battery" message at the same time stating the numerical value of capacity of the battery concerned so permitting the operator to decide if it is advisable to replace it. 14

20. Station (10) as in claim 1 , characterized in that it comprises a system of ventilation (25) for carrying away heat generated by the internal electronic circuits, and an internal thermostat (24) that switches off the charging circuits (120) if internal temperature exceeds the established level, and keeps them turned off until temperature values return to normal.

21 . Station (10) as in claim 1 , characterized in that there are ten slots (31).

22. Station (10) as in claim 1 , characterized in that there are four slots (31 ).

23. Station (10) as in claim 1 , characterized in that there is one slot (31 ).