GB2075247A

GB2075247A - Battery charging means

Info

Publication number: GB2075247A
Application number: GB8014780A
Authority: GB
Original assignee: Coal Industry Patents Ltd
Current assignee: Coal Industry Patents Ltd
Priority date: 1980-05-02
Filing date: 1980-05-02
Publication date: 1981-11-11
Also published as: GB2075247B

Abstract

Rechargeable battery equipment including at least one rechargeable battery cell (13) comprises a set of electrical output contacts (36, 37) for feeding electrical power from the battery to external equipment and a set of electrical input contacts (53, 54) for feeding electrical power to the rechargeable battery cell during recharging, electrically uni-directional conducting means (25, 26) ensure electrical power cannot be fed from the battery cell via the set of electrical input contacts. <IMAGE>

Description

SPECIFICATION Rechargeable battery This invention relates to rechargeable battery equipment.

In particular, although not exclusively, the present invention relates to rechargeable battery equipment for use with electrically powered equipment, for example electrically powered sensing instruments, in use, the battery equipment being fixedly attached to the associated electrically powered equipment.

It is known for such rechargeable battery equipment to comprise one set of external electrical contacts which in normal operation use constitute output contacts for feeding power to the electrically powered equipment and which during recharging constitute input contacts for feeding recharging power into battery means of the battery equipment.

A disadvantage of such a prior known rechargeable battery equipment is that in order to recharge the battery it is necessary to disconnect the battery equipment from the electrically powered equipment in order to expose the one set of external electrical contracts. This is a time consuming operation particularly as it is common practice to lock the battery equipment to the electrical equipment.

An object of the present invention is to provide an improved rechargeable battery equipment which overcomes or reduces the above mentioned problem.

According to the present invention rechargeable battery equipment comprises rechargeable battery mans, a set of electrical output contacts for feeding electrical power from the battery to external equipment, a set of electrical input contacts for feeding electrical power to the rechargeable battery means during recharging, and uni-directional conducting means for ensuring electrical power cannot be fed from the battery means to the set of electrical input contacts.

Preferably, the uni-directional conducting means comprises a diode arrangement.

Preferably, a switch prevents electrical power being fed to the electrical output contacts during recharging.

Conveniently, the switch is arranged to be operated by an external trigger provided on recharging equipment.

Preferably, vent means are provided to the battery means.

Conveniently, a fuse means are provided between the battery means and the two sets of electric contacts.

Advantageously, an external guide arrangement is provided for guiding the battery equipment into a recharging position on the recharging equipment.

Preferably, the guide arrangement and the electrical input contacts are provided on a side of the battery equipment and the switch is provided adjacent to the base of the battery equipment.

Preferably, a further guide arrangement is provided for guiding the external electrically powered equipment during assembly of the battery and powered equipment.

Advantageously, lock means are provided for locking the external electrically powered equipment to the battery equipment.

By way of example only, one embodiment of the present invention will be described with reference to the accompanying drawings, in which :- Figure 1 is a side view of rechargeable battery equipment constructed in accordance with the present invention; Figure 2 is an inverted plan of Figure 1; Figure 3 is a plan of Figure 1; Figure 4 is a section along line IV -IV of Figure 3; Figure 5 is a scrap view of a detail of Figure 4 drawn on an enlarged scale; Figure 6 is an incomplete section along line VI - VI of Figure 3; Figure 7 is a section along line VII - VII of Figure 3; and Figure 8 is a circuit diagram of the rechargeable battery equipment of Figure 1.

Figures 1 to 7 show the rechargeable battery equipment to comprise a tough, open topped outer casing 10 having two outwardly extending guides 12 constituting a slide arrangement on one side of the casing for guideable engagement with a cooperating slide arrangement provided on recharging equipment (not shown).

Within the casing 10 there is provided rechargeable battery means comprising two battery cells 13 and 14 which are connected in series by a wire (not shown) attached to tags 15 and 16 and each of which is vented to atmosphere via a resilient annular support 17 mounted on a perforated electrical insulating disc 18 and two perforated filter discs 19 in communication with vent holes 20 (omitted from Figures 4 and 5) formed in the base of the casing 10.

The vent holes provide exhaust passages preventing pressurisation due to discharge of gases formed during recharging and are necessary because the casing is filled with potting compound as will be explained later in the specification.

The battery equipment also comprises a printed circuit board 22 mounted in slides 24 and provided with two diodes 25 and 26 and an electrical fuse 28 having a screw cap 29 beneath a paraffin wax plug 30. The circuit board has electrical connection points 1 to 6 which are connected to wires 32 and which will be discussed in more detail later in the specification with reference to Figure 8.

A resiliently biassed switch 35 mounted adjacent to the base of the casing 10 is arranged to be activated by an upstanding trigger (not shown) provided on the recharging equipment. The switch is electrically mounted between the battery means and a set of electrical output contacts or sockets 36,37 provided on a panel board 38 secured at the top of the casing 10 by screws 39 and ensures that during recharging of the battery the positive socket is electrically disconnected from the battery. The switch includes an activating plunger 41 which is urged against a spring loading by engagement with the trigger and which is protected against external conditions by a resilient boot 42 and a thimble 43 engageable by the trigger when the battery equipment is placed on the recharging equipment.An upstanding guide peg 44 (shown only in Figures 3 and 7) serves to guide an electrically powered instrument (not shown) during its assembly with the rechargeable battery equipment, the powered equipment has electrical contact plugs for engagement with the sockets 36,37 and a recess for guideably accepting the upstanding peg.

A locking mechanism 45 is provided for fixedly locking together the assembled battery and powered equipment, the locking mechanism comprising a resiliently biassed locking spool 47 urged upwards as seen in Figure 4 by one coil spring 49 and having an engagement lip 50 for lockage engagement with a recess (not shown) provided on the powered equipment and a trianguler end formation 51 for engagement by a key (not shown) to lock or unlock the assembly.

A set of two electrical input contacts 53 and 54 are provided on one side of the casing 10 for electrical engagement during the recharging procedure by electrical output contacts (not shown) provided on the recharging equipment.

Figure 8 shows the electrical circuit diagram for the rechargeable battery equipment of Figures 1 to 7.

The set of electrical input contacts 53 and 54 are electrically connected to the diodes 25 and 26 via points 3 and 2 of the printed circuit board 22, the diodes being further connected to the battery cells 13 and 14 via points 6 and 4. The fuse 28 is mounted in the line connecting the diode 25 to the point 6.

The set of electrical output contacts or sockets 36 and 37 are connected to the battery cells 13 and 14 via points 5 and 1, point 5 being shorted to point 4 and point 1 being connected to the line connecting the diode 25 to the fuse 28.

The switch 35 is inserted in the line connecting point 1 to the output contact or socket 37.

Upon the rechargeable battery equipment being assembled as shown in Figures 1 to 7 and electrically connected as shown in Figure 8, the casing 10 is filled with a potting compound up to a level indicated at X in Figures 4 and 6, care being taken to ensure the battery cell vent passages to the base of the casing are not blocked by the compound and that no leakage of compound occurs through the base.

The battery and powered equipment then are assembled by holding the powered equipment over the battery equipment and engaging the peg 44 in the associated recess to guide the two equipments during assembly. The powered equipment is engaged on the lipped recess provided all around the upper rim of the casing 10 and the spool 47 of the locking mechanism 45 turned in a clockwise direction as indicated in Figure 2 to securely lock the two sets of equipment in the assembled position. In the assembled position the output contacts or sockets 36 and 37 are electrically engaged with associated input contacts provided on the powered equipment.

The rechargeable battery equipment can be recharged without disconnecting the powered equipment by simply engaging the guides 12 in associated vertical slides provided on the recharging equipment and sliding the assembled equipment downwards until the external input contacts 53 and 54 provided on the side of the casing 10 electrically make contact with electrical output contacts provided on the recharging equipment. The battery cells 13 and 14 then are recharged by a recharging current flowing via points 3 and 2 and the diodes 25 and 26.

As shown in Figure 8 the recharging current flows, from the positive input contact 53 via point 3, diode 25, fuse 28 and point 6 to the rechargeable battery cells 14 and 13. The return line to the negative input contact is via point 4, diode 26 and point 2.

Upon the battery equipment being located on the recharging equipment with the input contacts in engagement with the recharging contacts, the trigger provided on the recharging equipment contacts the thimble 43 and resilient boot 42 to activate the plunger 41 of the switch 35 against its spring loading to break the line from point 1 to the positive output contact 37. Consequently, throughout the recharging procedure which typically may take several hours the output from the battery equipment to the powered equipment is turned off.

However, upon the battery cells 13 and 14 being fully recharged and the assembled equipment being removed from the recharging equipment, the switch 35 disengages the trigger and the plunger 41 moves under its spring loading to re-close the outfeed line to recommence feeding electrical power to the electrically powered equipment via the set of output contacts 36 and 37.

The diode arrangement 25 and 26 ensures that the electrical flow in the recharging circuit is unidirectional and ensures that no electrical power can be fed from the battery cell 13 and 14 via the exposed input contacts 53 and 54.

From the above description it will be appreciated that the present invention provides rechargeable battery equipment which can be recharged without being disconnected from electrically powered equipment and which cannot feed electrical power from the battery cells via the exposed recharging input contacts. Such a condition makes the equipment suitable for use in potentially explodable conditions, for example, in an underground coal mine, where live electrical contacts cannot be tolerated.

Claims

1. Rechargeable battery equipment comprising rechargeable battery means, a set of electrical output contacts for feeding electrical power from the battery to external equipment, a set of electrical input contacts for feeding electrical power to the rechargeable battery means during recharging, and unidirectional conducting means for ensuring eiectrical power cannot be fed from the battery means to the set of electrical input contacts.

2. Equipment as claimed in claim 1 in which the unidirectional conducting means comprises a diode arrangement.

3. Equipment as claimed in claim 1 or claim 2 and including a switch arranged to be operated during recharging to prevent power being fed to the external contacts.

4. Equipment as claimed in claim 3 in which the switch is adapted to be operated by an external trigger on engagement of the equipment with recharging means.

5. Equipment as claimed in any proceding claim and including vent means to the battery.

6. Equipment as claimed in any preceding claim and including a fuse in series with the rechargeable battery means.

7. Equipment as claimed in any preceding claim and including guide means on or incorporated in a housing of the equipment for guiding the equipment into correct alignment with other equipment.

8. Equipment as claimed in any preceding claim and including lock means for securing the equipment to other equipment.

9. Rechargeable battery equipment substantially as hereinbefore described with reference to the accompanying drawings.