US1514378A - Interlocked fastening device particularly applicable to electrical apparatus - Google Patents

Description

, Nov. 4 1924.

4 1,514,378 H. J. FISHER ET AL INTERLOCKED FAS IENING DEVICE PARTICULARLY APPLICABLE TO ELECTRICAL APPARATUS Filed April 14, 1924 Patented Nov. 4, 1924.

HAaRY Joslirnrismanyor PHILA ELPHIA, AND JAMEs Mm-REY, OF EAST ENGLAND, AssIGno s To A. xn xnoulea OOMFANYIIMITED, crew-imam- TYNE," DURHAM, ENGLAND, 'A BRITISH 'COMZPANY.

INTERLOCKED TASTENI'NG DIivi cE r n-Trq LARLY 'A'PPLICAB'L A'PPA'R'ATTIS.

'lpgilica'tion fi'le'a April 14, 1924. Serial No. 76.1587.

To all whom it may comm; I

Be it' known that "fwe, HARRY JosriPH FISHE and James MI'RREY, subjects' ofjthe King of England, and'residing; respectively, 6 at Philadelphia, in thec'oun'ty of Durham, England, and East Boldon, in' 'the county 'of Durham, England, have invented certain new and useful Improvements inlfnterlocked Fastening Devices Pai'ticulaifly Applicable to Electrical Apparatus, of which the following is a specification. v r

This invention relates to a fastening device for securing two membersitogeth er of the type in which the device is interlocked with some Other'niechaniSI n in such an anner that the two members cannot be cau 'sed to'engage with one another'on'to disengage except when the other "iii'echa nism" is"'in some definite position. K t

The invention is more particularlyapplicable to electrical'apparatus, alndis p'riihztrily designed with the object ofl'pi oviding' an electrical plug and socket connection;"whrein the plug can only be, inserted in'the socket 'anism has been operated andban'not beiwithdrawn 'from the socket until after the switch or other mechanism has been'ret'urned to its initial position. 7 v

The fastening "device according' fto the present invention "comprises a bolt-"o1' rod pivoted to one of the twohneinbers itofbe secured together, and afdrum"or'sleeve movable longitudinally there-on, Apart the drum or a projection' thereon isso shaped as tolie in or out of'thepath of "an interlockingirodaccordingto the position of the drum on the bolt. heidru'rn' is caused to move alon 'thebolt inea-nsof a rotatable head or the like, wh1ch"'al'soengages "with e Qft wo members. n smh as "to these inehib'ers together in e'efiga hgP o 1 a V The "rotatable head may-hav two flanges :iiisiiitied to eng ge respectivel with the, two sides of a fslotted lugfon thefsecond ineniber sofas f ti) assist the engagement or separation f h 't l i b'e -v T e d ii n s h f again t idt'ation relative to the bolt and 'c'on= v'eiiientlyfits" projection "lies in the path of the interlocking r dije eepp when the two m m fi fimv' th' rt he. Wtdble head is preferably ftirfii'ed with a thread onjthe drum, between the druni and a'colla ij as to tendto variety; of purposes,

before a controllingswitchbrother "Inechv in such a manner drum lntoa position in lies in the path of the int he invention may 111 various ways and drawings illustrate by preferred arrangement" trical plug and Socket 0 ticularly intendedfor. us

places where it is of prevent the occurrence. of a spar E To Thou screw-thread engaging in a spr ng'fbeing provide? 1 fthebo niovelthe which its projection zl i f tgr d-n .t ,1 be carriedinto practlce' may be ailel sdfftl l c'mml yins em a a 'rli 'd t9 ankl i et pn I J' PQrPQ ral i sand. he r at m er nse to i b ase ing that the controlling ls w itch returned to the off-position before thef plugv is inserted in or withdrawn from the'so'cket. In

these drawings,

' Figure 1 shows the lpkie gb in horizontal section in the closed position, I

j Figure 2is a plan ofthe bolt in the open position, and

winged nuts which on the plug'C, position in the gure 3 is aside elevation ofthe bolt,

e socket A has pivpu fn 's st #1 h 1 re ammg rawings) carry soas to clainp the socket A, These nuts each carry two flanges which engage with one side or the other oftheocorresponding, lug and thus assist in withdrawing the a plug from thesocket or in inserti U The bolt B, oted at B surrounded n it therein. 1

used fo1 t1e interlock is .pivto lugs A on the socketand is by a drum. Dwvhich is free, .to

move longitudinally on the bolt but is keyed or slotted as at D,

of a slotted lug'C vided for this bolt threadfin the drum 1).

vided between the drum fi 'p the jb f B Lin tend to move the driim towa ii 1 of the bolt, outer and, which preve r p f l silch a to prevent it from rotating relative to the bolt ll? ther ig; sipmins t i i i s E ram being detached completely from the drum D. The end B of the bolt is arranged never to project beyond the head E so that the operators hand is protected from damage.

The drum D has a lateral projection D which is moved into and out of the path of an interlocking rod G as the head E is rotated. Thus when the plug C is clamped into the socket A, as shown in Figure 1, this projection 1) lies out of the path of the interlocking rod G, which is therefore free to move. Vhen, however, the head E is unscrewed to withdraw the plug C from the socket A, the drum D travels along the bolt B and brings the projection D into the path of this red G.

The interlocking rod G may be connected to any desired mechanism such for example as a switch controlling the electrical circuit containing the plug and socket. Thus when the plug is clamped in the socket and the projection D is out of the path of the interlocking rod G, the switch may be operated. hen the switch is turned into the on position, this rod G moves into the path of the rojection D and prevents the head E from eing unscrewed far enough to withdraw the plug. In Figure 3 the rod G is shown in this position, whilst the off position of the end of the rod is indicated in chain line at G.

W'hen the plug G is clamped in the socket A, the outer flange E of the head E is held tightly against the lug C on the plug by means of the spring F, this spring being made strong enough to prevent the plug from being withdrawn except by unscrewing the head E. When it is desired to withdraw the plug from the socket, the switch must be turned oil? to remove the interlocking rod G from the path of the projection D on the drum D. The head E is then unscrewed and the drum I) moves down along the bolt B under the action of the spring F, the outer flange E' of the head E still remaining in contact with the slotted lug C. After the drum D has reached the end of its travel and its projection D lies in the path of the inter locking rod G, the head E begins to move as it is rotated until its inner flange E comes into contact with the other side of the slotted lug C. The winged nuts on the other retaining bolts are also unscrewed until their inner flanges engage with the lugs, and further rotation of the head and theiruts causes the plug to begin to move out of the socket. The bolts are then swung out about their pivots until the head and the nuts cease to engage with the slotted lugs and the plug can be completely removed. This position is shown in Figure 2. Since the projection D on the drum D now lies in the path of the interlocking rod G, it is impossible to operate the switch while the plug is out of the socket. No current can therefore be flowing through the circuit while the plu is being withdrawn from or inserted into t ie socket, and it is therefore impossible for a spark to occur. It is also impossible for the terminals of the socket to be exposed when the switch is on and thus for anyone to receive a shock by touching the live socket terminals.

To clamp the plug into position in the socket, it is first of all inserted therein and the bolts are swung in until the nuts and the head are in engagement with the slotted lugs. Tightening up these members then forces the plug right home into the socket (this action being assisted by the spring F) and clamps it into position. Further rotation of the head E moves the drum 1) along the bolt B until its projection D is a ain out of the path of the interlocking ro G. The switch can now be operated. and the plug cannot again be withdrawn until the switch is in the off position.

i It will be understood that the construction described is given only by way of example and the details of construction may be varied without departing from the scope of the invention. Thus for example the head may make a screw-threaded engagement with the bolt as well as with the drum, the necessary motion of the drum being caused owing to a difierence between the pitches of the two threads. Modifications may also be made to suit the requirements of any particular purpose to which the fastening device according to the invention is applied.

What we claim as our invention and desire to secure by Letters Patent is 1. In a fastening device ad: ted to secure two members together and to interlocked with some other mechanism, the combination with the two members, of a bolt pivoted to one of the members, a rotatable head adapted to engage with the second member in such a manner as to clamp the two members together in the engaging position, a drum so connected to the head and the bolt as to move longitudinally along the bolt when the head is rotated, and an interlocking rod operated by the mechanism with which the fastening device is to be interlocked, the arrangement being such that a part of the drum lies in or out of the path of the interlocking rod acgording to the position of the drum on the olt.

2. In a fastening device, the combination of the two members which are to be secured together by the device, a bolt pivoted to one of the members, a slotted lug on the second member, a rotatable head having two flanges adapted to engage respectively with the two sides of the slotted lug so as to assist in the engagement or separation of the two members when the head is rotated a drum movable longitudinally on the bolt but held against rotation relative thereto, means whereby the drum is caused to travel along the bolt when the head is rotated, an interlocking. rod operated by some other mechanism with whichthe fastening device is to be interlocked, and a projection on the drum which lies in the path of the interlocking rod except when the two members are clamped together.

3. In a fastening device adapted to secure two members together and to be interlocked with some other mechanism, the combination with the two members, of a bolt pivoted to one of the members, a rotatable head adapted to engage with the second member in such a manner as to clamp the two members together in the engaging position, a drum movable longitudinally on the bolt but held against rotation relative thereto, the drum being provided with a screwthread engaging with a corresponding thread on the head whereby the drum is caused to travel along the bolt, when the head is rotated, an interlocking rod operated by the mechanism with which the fastening device is to be interlocked, and a projection on the drum which lies in the path of the interlocking rod exceptwhen the two members are clamped together.

4;. In a fastening device, the combination of the two members which are to be secured together by the device, a bolt pivoted to one of the members, a slotted lug on the second member, a rotatable head having two flanges adapted to engage respectively with the two sides of the slotted lug so as to assist in the engagement or separation of the two members when the head is rotated, a drum movable longitudinally on the bolt but held against rotation relative thereto, the drum being provided with a screwthread engaging with a corresponding thread on the head whereby the drum is caused to travel along the bolt when the head is rotated, and an interlocking rod operated by some other mechanism. with which the fastening device is to be interlocked, the arrangement being such that a part of the drum lies in or out of the path of the interlocking rod according to the position of the drum on the bolt.

5. In afastening device, the combination locking rod.

of the members, a slotted lug on the second member, a rotatable head having two flanges adapted to engage respectively with the two sides of the slotted lug so as to assist in the engagement or separation of the two members when the head is rotated, a drum movable longitudinally on the bolt but held against rotation relative thereto, the drum being provided with a screwthread engaging with a corresponding thread on the head whereby the drum is caused to travel along the bolt when the head is rotated, an interlocking rod operated by some other mechanism with which the fastening device is to be interlocked, a projection on the drum which lies in the path of the interlocking rod except when the two members are clamped together, and a spring which tends to move the drum into a position in which its projection lies in the path of the intertion with the two members, of a bolt pivoted to one of the members, a rotatable head adapted to engage with the second member in such a manner as to clamp the two members together in the engaging position, a drum movable longitudinally on the bolt but held against rotation relative thereto, the drum being provided with a screwthread engaging with a corresponding thread on the head whereby the drum is caused to travel along with the bolt when the head is rotated, an interlocking rod operated by the mechanism with which the fastening device is to be interlocked, a projection on the drum its projection lies in the path of the interlocking rod according to the position of the drum on the bolt, and a spring which tends to move the drum into a position in which its projection lies in the path of the interlocking rod.

In testimony whereof we have signed our names to this specification.

HARRY JOSEPH FISHER. JAMES MIRREY.

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