GB1568084A - Devices constructed for use in electrical circuits and comprising two separable parts - Google Patents
Devices constructed for use in electrical circuits and comprising two separable parts Download PDFInfo
- Publication number
- GB1568084A GB1568084A GB687476A GB687476A GB1568084A GB 1568084 A GB1568084 A GB 1568084A GB 687476 A GB687476 A GB 687476A GB 687476 A GB687476 A GB 687476A GB 1568084 A GB1568084 A GB 1568084A
- Authority
- GB
- United Kingdom
- Prior art keywords
- parts
- contacts
- switch
- relative positioning
- another
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- G—PHYSICS
- G08—SIGNALLING
- G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
- G08B17/00—Fire alarms; Alarms responsive to explosion
- G08B17/10—Actuation by presence of smoke or gases, e.g. automatic alarm devices for analysing flowing fluid materials by the use of optical means
- G08B17/117—Actuation by presence of smoke or gases, e.g. automatic alarm devices for analysing flowing fluid materials by the use of optical means by using a detection device for specific gases, e.g. combustion products, produced by the fire
-
- G—PHYSICS
- G08—SIGNALLING
- G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
- G08B17/00—Fire alarms; Alarms responsive to explosion
-
- G—PHYSICS
- G08—SIGNALLING
- G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
- G08B17/00—Fire alarms; Alarms responsive to explosion
- G08B17/10—Actuation by presence of smoke or gases, e.g. automatic alarm devices for analysing flowing fluid materials by the use of optical means
- G08B17/11—Actuation by presence of smoke or gases, e.g. automatic alarm devices for analysing flowing fluid materials by the use of optical means using an ionisation chamber for detecting smoke or gas
- G08B17/113—Constructional details
Description
(54) DEVICES CONSTRUCTED FOR USE IN ELECTRICAL
CIRCUITS AND COMPRISING TWO SEPARABLE PARTS
(71) I, CHARLES WILLIAM MAX
TED, a British subject, of 20--22 Gipsy Hill,
Crystal Palace, London SE19 1NL, formerly of 77, church Road, London, SE19 2TA, do hereby declare the invention, for which I pray that a patent may be granted to me, and the method by which it is to be performed, to be particularly described in and by the following statement: - According to a first aspect of the invention, a device constructed for inclusion in an electrical circuit includes a first part, which includes two electrical contacts and an electrical switch, and a second part which includes at least one electrical circuit element, the second part electrically connecting one of said contacts to the other or causing it to be electrically connected to the other and the switch being open in a first relative positioning of the first and second parts, whereas the second part is wholly out of contact with the first part and said contacts are electrically connected to one another not by or due to the second part but by the now closed switch in a second relative positioning of the first and second parts, these parts being such that in a change from the first relative positioning to the second relative positioning, said contacts automatically cease to be electrically connected to one another by or due to the second part, leaving them opencircuited for a short time, and subsequently the switch automatically closes to electrically connect said contacts to one another.
The device may be a signalling device, that is to say one that receives an electrical signal and in response to it produces at the device or near it a sensible indication, for example a visible and/or an audible warning signal, or a device that develops an electrical signal, for example a voltage generated at the device or a çhange of impedance of the device, that is transmitted to a distant signalling means where it produces a sensible indication, for example a visible and/or an audible warning signal.
Examples of the latter kind of signalling device are a smoke detector and a heat detector see my Patent Application No. 44246/74 (Serial number 1,491,222) for examples af these.
Preferably the second part includes first and second bridged electrical contacts which engage respective ones of said contacts of the first part (i.e. first and second contacts) in the first relative positioning of the first and second parts and each of the first and second parts includes a third contact, these third contacts also engaging one another in the first relative positioning of the first and second parts, the first part having wiring terminals connected to its second and third contacts and said electrical circuit element being connected between the second and third contacts of the second part.Whether or not the device has these features, preferably the device is one in which the first part is in the form of a ring with a plate-like part extending across it on which the contacts of the first part are mounted, the second part having a skirt which fits into the ring and on which there are pins, with heads, which engage in elongate holes, wider at one end, in said plate-like part, the con struction being such that in the first relative positioning of the first and second parts the pins are in the narrow parts of the holes and the heads prevent the pins coming out of the holes since the heads cannot pass through these narrow parts and when one of the first and second parts is turned with respect to the other respective contacts of the first and second parts come out of contact with one another and later the pins lie in the wider parts of the holes, through which the heads of the pins can pass, so that the first and second parts can be pulled apart and when they are pulled apart the switch automatically closes.
The switch may be one in which one of two electrical contacts is urged resiliently to directly engage the other or it may be a microswitch or relay or a semiconductor switching device. If the switch is of the first kind or the second kind indicated above and the device has the features described above in the sentence beginning "whether", the switch is preferably opened by a push-member on or actuated by the second part.
As noted above, the second part of the device may include first and second bridged electrical contacts which engage respective ones of first and second contacts of the first part of the device in the first relative positioning of the first and second parts of the device.
Then the second part of the device itself electrically connects to one another the first and second contacts of the first part of the device. Instead of this, the second part of the device may only cause these contacts to be connected to one another. For example, the second part of the device may include an operating member which operates a jack switch in the first part of the device. In the first relative positioning of the first and second parts of the device, contact members A and
B of the jack switch (which constitute the above-mentioned contacts of the first part) are held in engagement with one another by the operating member and contact members
C and D of the jack switch (which constitute the above-mentioned switch of the first part) are held out of engagement with one another by the operating member.In the second relative positioning of the first and second parts of the device contact members A and B are out of engagement with one another and contact members C and D are in engagement with one another, not due to the operating member but due to the construction of the jack switch.
In an intermediate relative positioning of the first and second parts of the device, contact members A and B are out of engagement with one another and contact members C and D are held out of engagement with one another by the operating member. Contact members A and C are permanently electrically connected together and so are contact members B and
D so there is always a connection between contact members A and C, on the one hand, and contact members B and D, on the other hand, except for a brief period when the relative positioning of the first and second parts of the device is being changed from the first relative positioning to the second relative positioning or vice versa.
According to a second aspect of the invention, the first parts of a plurality of devices each according to the first aspect of the invention, for example in accordance with any example described above, are connected together in a chain such that in the event of one or more of the devices having the second part missing this does not prevent the transmission of electrical signals between the second part of any other device which is in the first relative positioning and a signalling means if such is connected to one end of the chain. If each device has the features described above in the sentence beginning "Preferably", the second and third contacts of the first part of one device are preferably connected to the first and
third contacts, respectively, of the preceding
device in the chain.
According to a third aspect of the invention,
there is provided a signalling means connected
to a device according to the first aspect of the
invention for example in accordance with any
example described above, or a chain of the first
parts of devices according to the second aspect
of the invention, the signalling means being so
constructed that on the device or one of the
devices changing from the first relative
positioning to the second relative positioning,
the consequent brief open-circuiting of said
contacts of the device brings about a signal
at the signalling means which persists long
after the switch of the device in question has
closed.
Two examples in accordance with the invention are described below with reference to
the accompanying drawings, in which: Figure 1 shows a circuit diagram of a fire
warning system,
Figure 2 shows a side view of a device
according to the first aspect of the invention,
Figure 3 shows a plan view of part of the
same device, and
Figure 4 shows a modification of what is
shown in Figures 2 and 3.
Figure 1 shows three smoke detectors 1, 2 and 3 forming part of a chain of many more than three identical smoke detectors at appropriate locations throughout a building.
Each smoke detector includes a first part
having five electrical contact springs la to le in a circle and mounted on a ring-shaped body of electrically insulating material, the distance, measured around the circle, between each two adjacent contact springs being one-sixth of the circumference of the circle, except in the case of contact springs la and le, in which case the distance is one-third of the circumference.In each case the contact springs la and ib are permanently connected together within the
first part and there is also within the first part a switch 4 which, when closed, bridges the contact springs ib and ic. Each smoke detector further includes a second part having six electrical contact bosses 2a to 2f distributed at equal intervals around a circle, which is in fact of the same diameter as the circle on which the contact springs la to le lie, although on the drawing it looks smaller, the bosses being near the top of a housing containing the circuit elements of the smoke detector, for example according to Figure 4 of my Patent Application No. 44246/74 (Serial number 1,491,222). The contact bosses 2b and 2c and also the contact bosses 2d and 2e are permanently connected together within the second part of the device by metal laid on a flat base of electrically insulating material by printed circuit technique. When a skirt at the bottom of the housing of the second part is inserted in a recess in the ring shaped body of the first part and the second part is turned, the contact springs la to le are contacted by and press against the contact bosses 2a to 2e, respectively, and the switch 4 is open.
Two wires 5 and 6 connect a signalling means 7 to wiring terminals connected to the contact springs ic and id, respectively, of the first smoke detector 1 and two wires 8 and 9 connect wiring terminals connected to the contact springs ib and ld of the first smoke detector 1 to wiring terminals connected to the contact springs ic and id, respectively, of the second smoke detector 2, wiring terminals connected to the contact springs ib and id of the second smoke detector 2 being connected by wires 10 and 11 to wiring terminals connected to the contact springs ic and id of the third smoke detector 3, and so on along the chain of smoke detectors, the last of which has a monitoring component, for example a resistor or a Zener diode connected to wiring terminals connected to its contact springs lb and Id so as to complete a loop connected to the signalling means 7.
The contact springs ib and Ic of the first part of each smoke detector are normally electrically connected together by the second
part of the smoke detector, i.e. by the contact bosses 2b and 2c and the metal bridging them.
This is the above-mentioned first relative positioning of the two parts. If, say, the smoke detector 2 detects smoke, there is a substantial
reduction of resistance of a circuit element or set of circuit elements connected between its contact bosses 2c and 2d and thus between its contact springs lc and id, between the wires 8 and 9 and between the wires 5 and 6 since the contact spring lb is electrically connected to the contact spring lc by the contact bosses 2b and 2c and the metal bridging them.
In the same way, a fall in resistance between
the contact bosses 2c and 2d of any of the smoke detectors appears also between the wires 5 and 6. This fall in resistance brings about a visible and/or an audible signal at the
signalling means 7. If the switch 4 were not present in the first smoke detector, removal of the second part of that smoke detector from
the first part, for repair or replacement or as an act of vandalism, would render all the other smoke detectors inoperative in that they are no longer connected to the signalling
means 7 and likewise if there were no switch
4 in the second smoke detector 2, removal of its second part would render inoperative all
the smoke detectors except the smoke detector
1.By virtue of the switches 4, which auto
matically close when the second part of a
smoke detector is moved and taken right
away from its first part, the first and
second parts then being in the second
relative positioning mentioned above, the
contacts ib and ic of any smoke detector
are still bridged even when the second part ob the smoke detector is absent and so any drops in resistance between the contact bosses 2c and 2d of the smoke detectors have an effect at the signalling means 7.
Figure 2 shows that the second part of the smoke detector comprises a housing 12, which contains the circuit elements of the smoke detector, the housing having at its top a skirt 13 surrounding the circle of contact bosses, which are not shown but are cylinders that are vertical when the housing is positioned as shown in Figure 2. The first part of the smoke detector includes a ring 14 of electrically insulating material with a plate-like part 15 extending across it. On the lower side (considering
Figure 2) of this plate-like part are the contact springs, not shown, which are secured by screws 16. The plate-like part 15 has a hole 17 centrally through it and there are three further holes through it similar to one another irregularly distributed about the centre of the part 15.Each of these holes has a narrow part 18 and a wide part 19 through which can pass the head 20 of one of three pins 21 screwed into the skirt 13. The skirt 13 is positioned inside and close to the ring 14 with all the three pins 21 passing through the wide parts 19 of the holes and the heads 20 of the pins above, considering Figure 2, the plate-like part 15 and then the housing 12 is grasped and turned anti-clockwise (considering Figure 3) so that the pins 21 pass into the narrow parts 18 of the holes through the plate-like part 15, the heads 20 of the pins still lying above the plate-like part 15, considering Figure 2, so that the housing 12 is now fixed to the platelike part 15 with the contact springs on the first part of the smoke detector engaging the contact bosses in the second part.
When the housing 12 was positioned with
its skirt 13 inside the ring 14, the upper edge
of the skirt pressed on the free end of a pin
22 (in this case a screw) which has a head 23 and passes through the plate-like part 15. This caused the head 23 of the pin to engage a
resilient actuating blade 24 of a microswitch
4, opening the microswitch. When the housing
is now turned clockwise, considering Figure 3,
and pulled away from the ring 14, firstly,
during the turning movement, all the contact
bosses on the second part of the smoke de
tector come out of contact with the contact
sprngs on the first part so that the contact
springs ib and lc are momentarily open
circuited and this open-circuit condition on
the wires 5 and 6 sets up a fault signal con
dition in the signalling means 7.Then the
skirt 13, during the pulling movement, comes
out of contact with the pin 22, which is pushed
downwardly, considering Figure 2, by the
actuating blade 24, which causes the micro
switch 4 to close. The fault signal condition
is maintained at the signalling means 7, in
dicating that one of the smoke detectors is out
of order, but all the other smoke detectors can influence the signalling means 7.
A disadvantage of what is shown in Figures 2 and 3 is that the microswitch is too big to be accommodated wholly within the ring 14.
A possible alternative is to have on the skirt 13 another screw which holds a spring-loaded contact 26 (Figure 4) of the switch 4 away from the other contact 27 of the switch until the housing 12 is moved away from the ring 14, allowing the switch 4 to close, the switch 4 being entirely within the ring 14.
Instead of smoke detectors, the chain of devices connected to the signalling means 7 could comprise only open-circuit heat detection devices, for example according to Figure 2 of my earlier patent application, or only alarm signalling units, for example according to
Figure 3 of my earlier patent application.
Instead there could be two or more differing kinds of signalling devices in the chain, for example some of each of the devices shown in Figures 2 to 4 of my earlier patent application. Another possibility is for all the devices 1 to 3, etc., in the chain to be firealarm bells or other fire-alarm devices energised from the signalling means 7. If the second part of one is removed, the others still function.
In another device which may be used in place of the device shown in Figures 2 and 3, the second part of the device includes an operating member which is in the form of a pin which passes through a hole in a printed-circuit board in the first part of the device and operates a jack switch in the first part of the device on the far side of the printed-circuit board. In the first relative positioning of the first and second parts of the device, with the pin fully inserted, contact members A and B of the jack switch (which constitute the above-mentioned contacts of the first part) are held in engagement with one another by the operating member and contact members C and D of the jack switch (which constitute the above-mentioned switch of the first part and are nearer the root of the pin than are the contacts A and
B) are held out of engagement with one another by the operating member.In the second relative positioning of the first and second parts of the device contact members
A and B are out of engagement with one another, not due to the operating member but due to the construction of the jack switch, which is such that contacts A and B are normally open and contacts C and D are normally closed. In an intermediate relative positioning of the first and second parts of the device, contact members A and B are out of contact with one another and contact members C and D are held out of engagement with one another by the operating member.
Contact members A and C are permanently electrically connected together and so are contact members B and D so there is always a connection between contact members A and
C, on the one hand, and contact members B and D, on the other hand, except for a brief period when the relative positioning of the first and second parts of the device is being changed from the first relative positioning to the second relative positioning, or vice versa.
The operating member (i.e. the pin) pro jects from one corner of a six-sided plate in the second part of the device and into one corner of the printed-circuit board, which is substantially diamond shaped. Another pin projects from the centre of the plate through a hole in the centre of the printed-circuit board. These two pins and the holes which receive them constitute locating means for assembling the two parts of the device. When assembled, five shorter and thinner pins, spaced in a ring around the central pin, project through holes in the printed-circuit board and make contact with the printed circuit on it.
WHAT I CLAIM IS:
1. A device constructed for inclusion in an electrical circuit including a first part, which includes two electrical contacts and an electrical switch, and a second part which includes at least one electrical circuit element, the second part electrically connecting one of said contacts to the other or causing it to be electrically connected to the other and the switch being open in a first relative positioning of the first and second parts, whereas the second part is wholly out of contact with the first part and said contacts are electrically connected to one another not by or due to the second part but by the now closed switch in a second relative positioning of the first and second parts, these parts being such that in a change from the first relative positioning to the second relative positioning, said contacts automatically cease to be electrically connected to one another by or due to the second part, leaving them open-circuited for a short time, and subsequently the switch automatically closes to electrically connect said contacts to one another.
2. A device according to claim 1 in which the second part includes first and second bridged electrical contacts which engage respective ones of said contacts of the first part (i.e. first and second contacts) in the first relative positioning of the first and second parts and each of the first and second parts includes a third contact, these third contacts also engaging one another in the first relative positioning of the first and second parts, the first part having wiring terminals connected to its second and third contacts and said electrical circuit element being connected between the second and third contacts of the second part.
3. A device according to claim 1 or 2 in
**WARNING** end of DESC field may overlap start of CLMS **.
Claims (15)
1. A device constructed for inclusion in an electrical circuit including a first part, which includes two electrical contacts and an electrical switch, and a second part which includes at least one electrical circuit element, the second part electrically connecting one of said contacts to the other or causing it to be electrically connected to the other and the switch being open in a first relative positioning of the first and second parts, whereas the second part is wholly out of contact with the first part and said contacts are electrically connected to one another not by or due to the second part but by the now closed switch in a second relative positioning of the first and second parts, these parts being such that in a change from the first relative positioning to the second relative positioning, said contacts automatically cease to be electrically connected to one another by or due to the second part, leaving them open-circuited for a short time, and subsequently the switch automatically closes to electrically connect said contacts to one another.
2. A device according to claim 1 in which the second part includes first and second bridged electrical contacts which engage respective ones of said contacts of the first part (i.e. first and second contacts) in the first relative positioning of the first and second parts and each of the first and second parts includes a third contact, these third contacts also engaging one another in the first relative positioning of the first and second parts, the first part having wiring terminals connected to its second and third contacts and said electrical circuit element being connected between the second and third contacts of the second part.
3. A device according to claim 1 or 2 in
which the first part is in the form of a ring with a plate-like part extending across it on which the contacts of the first part are mounted, the second part having a skirt which fits into the ring and on which there are pins, with heads, which engage in elongate holes, wider at one end, in said plate-like part, the construction being such that in the first relative positioning of the first and second parts the pins are in the narrow parts of the holes and the heads prevent the pins coming out of the holes since the heads cannot pass through these narrow parts and when one of the first and second parts is turned with respect to the other respective contacts of the first and second parts come out of contact with one another and later the pins lie in the wider parts of the holes, through which the heads of the pins can pass, so that the first and second parts can be pulled apart and when they are pulled apart the switch automatically cloees.
4. A device according to any preceding claim in which the switch is one having two contacts one of which is resiliently urged to engage the other directly.
5. A device according to any one of claims 1 to 3 in which the switch is a micro-switch.
6. A device according to claims 3 and 4 or claims 3 and 5 in which the switch is opened by a push-member on or actuated by the second part.
7. A device according to any one of claims
1 to 3 in which the switch is a relay or a semiconductor switching device.
8. A device according to any preceding claim which is such as to receive an electrical signal and in response to it produce at the device or near it a sensible indication.
9. A device according to any one of claims
1 to 7 which develops an electrical signal for transmission to a distant signalling means for producing there a sensible indication.
10. A device according to claim 1 in which the second part of the device includes an operating member which operates a jack switch in the first part of the device and in the first relative positioning of the first and second parts of the device contact members
A and B of the jack switch (which constitute the above-mentioned contacts of the first pan) are held in engagement with one another by the operating member and contact members
C and D of the jack switch (which constitute the above-mentioned switch of the first part) are held out of engagement with one another by the operating member, whereas in the second relative positioning of the first and second parts of the device contact members
A and B are out of engagement with one another and contact members C and D are in engagement with one another, not due to the operating member but due to the construction of the jack switch, and in an intermediate relative positioning of the first and second parts of the device contact members
A and B are out of engagement with one another and contact members C and D are held out of engagement with one another by the operating member, contact members A and C being permanently electrically connected together as are contact members B
and D so there is always a connection between contact members A and C, on the one hand,
and contact members B and D, on the other hand, except for a brief period when the relative positioning of the first and second parts of the device is being changed from the first relative positioning to the second relative positioning or vice versa.
11. A device for inclusion in an electrical circuit, substantially as described above with reference to Figures 1 to 3 of the accompanying drawings or Figures 1 to 3 with the modification shown in Figure 4.
12. Apparatus comprising a plurality of devices each according to any preceding claim with their first parts connected together in a chain such that in the event of one or more of the devices having the second part missing this does not prevent the transmission of electrical signals between the second part of any other device which is in the first relative positioning and a signalling means if such is connected to one end of the chain.
13. Apparatus according to claim 12 in which the devices are in accordance with claim 2 and the second and third contacts of the first part of one device are connected to the first and third contacts, respectively, of the preceding device in the chain.
14. A system comprising a signalling means connected to a device according to any one of claims 1 to 11 or to apparatus according to claim 12 or 13, the signalling means being so constructed that on the device or one of the devices changing from the first relative positioning to the second relative positioning, the consequent brief open-circuiting of said contacts of the device brings about a signal at the signalling means which persists long after the switch of the device in question has closed.
15. Apparatus comprising a chain of devices connected together and each comprising first and second separable parts, the apparatus being substantially as described above with reference to Figures 1 to 3 of the accompanying drawings or Figures 1 to 3 with the modification shown in Figure 4.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB687476A GB1568084A (en) | 1977-04-25 | 1977-04-25 | Devices constructed for use in electrical circuits and comprising two separable parts |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB687476A GB1568084A (en) | 1977-04-25 | 1977-04-25 | Devices constructed for use in electrical circuits and comprising two separable parts |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| GB1568084A true GB1568084A (en) | 1980-05-21 |
Family
ID=9822367
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB687476A Expired GB1568084A (en) | 1977-04-25 | 1977-04-25 | Devices constructed for use in electrical circuits and comprising two separable parts |
Country Status (1)
| Country | Link |
|---|---|
| GB (1) | GB1568084A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2462749A1 (en) * | 1979-07-27 | 1981-02-13 | Hochiki Co | FIRE DETECTOR AND FIRE ALARM SYSTEM USING SUCH A DETECTOR |
| GB2134680A (en) * | 1983-02-02 | 1984-08-15 | Sound Diffusion Plc | Monitored line alarm systems |
| GB2137390A (en) * | 1983-03-07 | 1984-10-03 | Emhart Ind | Sensor assembly |
| GB2254946A (en) * | 1991-04-19 | 1992-10-21 | Manher Amlani | Alarm system |
-
1977
- 1977-04-25 GB GB687476A patent/GB1568084A/en not_active Expired
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2462749A1 (en) * | 1979-07-27 | 1981-02-13 | Hochiki Co | FIRE DETECTOR AND FIRE ALARM SYSTEM USING SUCH A DETECTOR |
| GB2134680A (en) * | 1983-02-02 | 1984-08-15 | Sound Diffusion Plc | Monitored line alarm systems |
| GB2137390A (en) * | 1983-03-07 | 1984-10-03 | Emhart Ind | Sensor assembly |
| GB2254946A (en) * | 1991-04-19 | 1992-10-21 | Manher Amlani | Alarm system |
| GB2254946B (en) * | 1991-04-19 | 1995-01-04 | Manher Amlani | Alarm system |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PS | Patent sealed | ||
| PCNP | Patent ceased through non-payment of renewal fee |