US2978547A - Electric circuit controllers - Google Patents

Description

J. G. NASH 2,978,547 ELECTRIC CIRCUIT CONTROLLERS 2 SheetsSheet 1 April 4, 1961 Filed 001;. 22, 1958 s T w w QM NR R H \w WN MN ww fiwY Q fi m JJ; 3 P pl. ikmiiin l QM m m k ww mwfi m j l m m n R mw ww M T R Rm ww WWRNNQN %\1 A. NN

April 4, 1961 J. G. NASH 2,978,547

ELECTRIC CIRCUIT CONTROLLERS Filed Oct. 22, 1958 2 Sheets-Sheet 2 United States Patent ELECTRIC CIRCUIT CONTROLLERS James Gentle Nash, Harrow,,England,iassignor to McCorquodale & Company Limited, London, England, aBritish company FiledOct. 22, 1958, Ser. No.- 768,920 Claims priority, application Great Britain Oct. 23, 1957 11 (Cl-120 Thisinvention concerns controllers: for electriccircuits which operate on a timecycle to open and/or close a circuit automatically at specified intervals.

The invention has for its object the provision of. a circuit controller-which enables sensitive control to be efiEected when the time cycle is of relatively long duration. Thus, for example, the invention finds application to controllers which are required to actuate acircuit once in half-an-hour, the instant of actuation beingaccurate to within a few seconds.

According to this invention a circuit controller comprises a frame, at least one stationary switch contact carried by the frame, a helical element rotatably mounted in said frame and axially adjustable thereof from an initialposition to. co-act with the switch contact for making and breaking a circuit, means for rotatably driving thehelical element, a screw-thread coupling between theelementand the frame, having the same helical pitch as said element,

for moving the element axially of the frame away from said initial position with rotation of the element and means for releasing said screw-thread coupling for returning the helical element axially of the frame to said initial position.

A practical construction of circuit controller according to this invention will now be described, by way of example only, with reference to the accompanying drawings whereof:

Fig. 1 is a plan view'of the circuit controller,

Fig. 2 is a section on th'e'line II--II of Fig. 1,

' Fig. 3 is a section on the line IIIIII of Fig. 1,

Fig. 4 is a view in the direction of the arrow 4 of Fig. 1 showing a part of the controller to a larger size, and

Fig. 5 is a section on the line V-V of Fig.4.

Referring to the drawings: the circuit controller comprises a frame upon one end of which there is mounted an electric motor 11 Which drives a carrier member in the form ofa shaft 12 through reduction gearing, generally indicated at 1'3. The carrier shaft 12 extends lengthwise of the frame 10 between uprights 14. The carrier shaft 12 is rotatably mounted in the uprights andv a plurality of bobbins, generally indicated 'at 15 in Fig. l are mounted upon the shaft 12 for rotation therewith.

A bar 16 extends between the uprights 14 and is pivotallysecured thereto at 17, 18. A row of stationary switches 19 is carried by the bar '16, one switch;19being provided for each bobbinlS. As moreparticularly shown in. Figs. .2 and 5 the switch 19 comprises fingers 20 and contacts 21, one of which is carried by each finger. The lower finger 20 also carries an actuator 22 which coacts with the bobbins 15 as later described.

The'switches19 are suitably'connected to the circuits which are to be controlled.

Each'bobbin 15 is formed with, a helicalgroove 23 and of the "thread 24 is a pair of springgroove 23. The pitch of the 15 is the same.

An arm 25 is pivoted, at 26; to an upright 1'4'and the arm 25 isdrawn downwardly. (see Fig. 3) by a spring 27 secured to the frame 10. The arm 25 is formed with a part-circular lead screw to engage the threaded part 24 of the shaft 12 and a hand lever 28 is provided to release the lead screw from the shaft 12 by raising the arm 25.

The bar 16 is carried by a bracket 29, see Fig. 2, which has alug 30,by which the bar 16 is pivoted, at 18, to the upright 14; The other end of the bar 16 is similarly secured to the upright 14 at 17. In this instance, however, the lug 30 is carried .around one edge of the upright 14to form an arm 31 which, as shown more particularly in.Fig. 3, is connectedby a spring 32 to thearm 25. The arm 31 is also connected by a spring 33 to a crossbar grooves 23 for each bobbin 34 which forms a part of the frame 10.

the bobbin are of metal and are soldered or brazed together. In an alternative arrangement each helical member 37 may constitute a resilient clip which is sprung into the helical groove 23 to grip the bobbin 15. With this arrangement the member 37 must extend more than halfway round the circumference of the bobbin 15. As is apparent from Fig.

short when they are soldered or brazed to the bobbin 15.

The bobbin 15 is arranged for anti-clockwise,rotation.

as shown in Fig. 5 and the leading edge of each rod 37 is charnfered, as at 38, and similarly the edge of the actuator 22 which is first engaged by theedge 38 is also chamfered, as at 39.

In the open-circuit position of the switches 19 the actuators 22 lie partlywithin the as the bobbins 15 rotate to bring, the rods 37 beneath the actuators 22 the latter will be raised to close the contacts 21 and. complete the circuit. The trailing edge of each rod 37 has a vertical face 40 and the back face 41 of the actuator 22 is similarly formed. Thus, when the rod 37' shaft 12 through pins 44 which slide in slots 45 in the.

shaft 12.

The shaft 12 carries a disc 46 pair of contact rollers 47, 48 49. The switch roller 47 is nearer to the disc 47 than is the switch roller 48. 1

The switch which is controlled by the roller 47 is provided, in the particular instance being described, to actuate a warning device e.g. a lamp which notifies the operator that the process which is being electrically controlled has been completed. Thereafter the motor 11 continues to drive the shaft 12 until the switch roller 48 is actuated. The switch controlled by the roller 48' then opens the circuit to the motor 11 so that the controller is rendered inoperative.

' In use the shaft tion as shown in Fig. l andthe arm 25- is in engagement with the threaded part 24 of the shaft.. The switches'l9 are open, all of the rods-37 being spaced from the actuators 22. A, circuit to. the motor 11 which. is opposite a 5 the members. 37 may be relatively grooves 23. Consequentlywhich actuate switches 12is in its extreme left hand posiis: closed. and as a consequence the shaft 12 is rotated. Because of the engagement of the screwthread coupling 24, 25 the shaft is moved axially to the right, as seen in Fig. 1, while his rotated. Since the pitch of the screwed part 24 is the same as the pitch of the grooves 23 ofthe bobbins- ,the switches 19 willremain aligned with the grooves 23. In other words, the groove 23 of each bobbin 15- will move beneath its actuator 22 so that the groove 23 is always vertically beneath the actuator-this is the, relative positionshown in Fig. 4.

When a rod 37 is brought beneath an actuator 22 the corresponding switch .19 is closed to control the associated circuit. The circuits will be controlled in a predetermined sequence dependent upon the relative positions of the rods 37. When each bobbin 15 has been moved so that the associated actuator 22 has travelled from the left hand end of the bobbin to the right hand end thereof the sequence of circuit. controls will have been completed. It is at this instance that the shaft 12 will have been carried towards theright to such an extent that the disc 46 engages the switch roller 47 to complete the circuit, through the switch 49, to the warning device. Thereafter further rotation of the shaft 12 continues until the switch roller 48 is actuated. The motor 11 is then stopped. It is arranged that this occurs at the instant when the assembly comprising the shaft 12 and the bob- 4 i switch for opening the motor circuit, and means for actuating said switch upon a predetermined axial movement of the cylindrical element from its initial position.

3. A circuit controller according to claim 2 wherein a further switch is provided and means for actuating the further switch upon an axial movement of the cylindrical element less than said predetermined movement to complete a circuit to a warning device.

4. A circuit controller as claimed in claim 1 in which the rod member constitutes a resilient clip which is sprung into the helical groove in the cylindrical body.

5. A circuit controller according to claim 1 wherein the rod member is pre-formed to be of part-circular shape and the member and the cylindrical body are of metal and are soldered or brazed together.

6. A circuit controller comprising a frame, at least one switch contact carried by the frame, a helically grooved cylindrical body rotatably mounted in said frame and axially adjustable from an initial position relative to the frame, a rod'member secured in and extending along the groove to co -act with the switch contact for making and breaking'a circuit when said cylindrical body I is axially adjusted from its initial position, driving means for rotatably driving the cylindrical body, a screwbins 15 are in the same angular position to that in which they started. The operator then raises the hand lever 28 to disengage the arm 25 from the threaded part 24 whereupon spring 42 urges the assembly 12, 15 back to its original position. A collar 50 engages the left-hand upright 14 of Fig. 1 when the assembly 12, 15 has been returned by the spring 42 to its original position. When the lever 28 is raised the, bar 16 is rocked so as to lift the switches 19 and the actuators 22 clear of the bobbins 15. It is arranged that this occurs slightly before the arm 25 disengages the threaded part 24 to permit axial movement of the assembly 12, 15.

When the lever 28 is released the arm 25 is brought by spring 27 into re-engagement with the part 24. The apparatus is then in the same position as when the control commenced. This is the initial position of the helical elements 37 as referred to above.

The circuit controller may then be started by connecting the-motor 11 to a source of electrical supply.

The bobbins 15 may be easily andcheaply manufacturedto a standard design, the duration of the controltime and intervals of actuation being varied by vary threaded coupling between the cylindrical body and the frame, having the same helical pitch as the groove in said body, for moving the body axially away from said initial position with rotation of the'body, andmeans forreleasing said screw threaded coupling for returning the cylindrical body to said initial position.

7. A circuit controller comprising a frame, a carrier member, a screw-threaded coupling between the carrier member and the frame, driving means for rotatably driving the carrier member thereby axially to adjust the carrier member relative to the frame, a plurality of switch contacts on the frame, for each switch contact a helicallygrooved cylindrical body fixed on said carrier member and a rod member secured in and extending along the groove in the body to co-act with the switch contact for: making and breaking a circuit when the body is axially adjusted away from an initial position by rotation of said. carrier member, the grooves in the cylindrical body having the same helical pitch as said coupling.

8. A circuit controller comprising a frame, a carriermember, a screw threaded coupling between the carrier member and theframe, driving means for rotatably. driving the carrier member thereby axially to adjust the carrier member relative to the frame, a plurality of switch ing the length of the helical elements 37 and the distance between successive, spaced elements. 7

While in the particular arrangement described the helicalelements 37 raise the actuators 22 to close the contacts 21 and complete a circuit it may be arranged that the elements 37 adjust the actuators 22 to separate the v contacts 21 and'open the circuit.

1 In yet another arrangement the helical elements 37 may form part of the'cir'cuit which is to be controlled, the actuators 22 constituting conductor brushes which engage the elements 37. The conducting brushes are then-suitably insulated from the elements 37.

.I claim:

l. A circuit controller comprising a frame, at least one switch contact carriedv by the frame, a helically grooved cylindrical body rotatably mounted in said frame and axially adjustable from an initial position relative to the frame, a rod member secured in and extending along the groove to co-act with'the switchco'ntact for making and breaking .a circuit when said {cylindrical body is axially adjusted from itsinitial position, driving means for rotatably driving 'the cylindrical body, and a-screw 1211A circuit controller as claimed inclaim '1 in which the...driving meansis anelectric motor, and there isa contactsonthe frame, for each switch contact a helically grooved cylindrical body fixed on said carrier member and a rod member secured in and extending along the. groove in the bodyto co-act with the switch contact for making and breaking a circuit when the body is axially adjusted away from an initial position by rotation of said carrier member, the grooves in. the cylindrical body having the same'helical pitch as said coupling, means urging the carrier member axially to'carry the cylindrical bodies each to their initial position, and. manual release means for manually releasing the screw threaded coupling to allow axial movement of said carrier member to move the cylindrical bodies to their initial position.

9. A circuit controller as claimed in claim 8, wherein the manual release means is connected with the switch contacts to move'them away from the rod members as:

the. coupling is released.

.110. A'circuit controller comprising a frame, at least' one switch'contact carried by the frame, a helical element rotatably mounted in said frame and axially adjustable from aninitial position relative to the frame to co--.

act with the switch contact for making and'breaking a,- circuit, driving means for rotatably driving-the helical element, a screw-threaded coupling between the element. and the frame, having the same helical pitch as said element, for moving the element axially of the frame,

away from said initial position with rotation of the" element, means tor -releasing the screw threaded coupling" 5 to permit the return of the helical element to its initial position, and means connecting said releasing means with the switch contact to move the contact away from the helical element as the coupling is released.

11. A circuit controller comprising a frame, a helically grooved carrier member mounted for rotation and axial movement relatively to the frame, a screw-threaded coupling between the carrier member and the frame means for manually releasing the screw threaded coupling to allow axial movement of the carrier member relatively to the frame, driving means for rotatably driving the carrier member thereby axially to adjust the carrier member relative to the frame, a switch contact carried by said frame, and a helical rod member fixedly carried in the helical groove of the carrier member to 15 5 said coupling.

References Cited in the file of this patent UNITED STATES PATENTS 10 2,172,623 Pitney Sept. 12, 1939 2,641,661 Puerner June 9, 1953 v 2,818,473 Geder Dec. 31, 1957 FOREIGN PATENTS 571,328 Germany Feb. 27, 1932

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