US3290631A

US3290631A - Latched closed electric solenoid switch

Info

Publication number: US3290631A
Application number: US301858A
Authority: US
Inventors: Bedggood Victor; Fagan Eric Arthur Adam
Original assignee: Albright Engineers Ltd
Current assignee: Albright Engineers Ltd
Priority date: 1963-07-18
Filing date: 1963-08-13
Publication date: 1966-12-06
Anticipated expiration: 1983-12-06

Description

Dec. 6, 1966 V, BEDGGQQD ETAL 3,290,631

LATCHED CLOSED ELECTRIC SOLENOID SWITCH Filed Aug. 13, 1963 5 Sheets-Sheet 1 Dec. 6, 1966 V, BEDGGQOD ET AL 3,290,631

LAICHED CLOSED ELECTRIC SOLENOID swIICH 5 Sheets-Sheet 2 Filed Aug. 13, 1963 Dec. 6, 1966 v BEDGGOOD ETAL 3,290,631

LATCHED CLOSED ELECTRIC SOLENOID SWITCH Filed Aug. 15, 1963 5 Sheets-Sheet 5 lll-7&5

United States Patent O LATCHED CLOSED ELECTRIC SOLENOID SWITCH Victor Bedggood, Maidens Green, Bracknell, and Eric Arthur Adam Fagan, Copthorne Common, Copthorne,

England, assiguors to Albright (Engineers) Limited,

Surbiton, England, a British company Filed Aug. 13, 196s, ser. No. 301,s5s Claims. (Cl. 335-168) This invention relates to electric solenoids. of the kind which include a single solenoid winding and the invention is particularly but not exclusively applicable to electric switches operable by means of such solenoids. Such solenoids having a variety of uses where it is required to impart movement to a particular component as a result of energisation of the solenoid winding Iby means of a direct or alternating electric current, the solenoid including an armature member which may be mounted coaxially within the winding, which armature when moved as a result of energisation of the winding imparts the necessary movement to the component. It is usual to provide a spring either associated with the armature or the component whereby the armature and also the component will return to its initial position when the winding circuit is broken. Such solenoids have many uses and are commonly employed in electric actuators or in the operation of electric switches,

In known solenoid operated electric switches of this type, energisation of the solenoid Winding effects closure of the main contacts of the switch and such contacts are held closed for as long as the winding is energised. The contacts are spring-biassed to the open position and return to the open position under the action of the associated spring upon de-energisation of the solenoid winding. Thus with such known arrangements, in order to retain the contacts in the closed position, the current supply to the solenoid winding must necessarily be maintained, resulting in a fairly heavy expenditure in energising current.

It is an object of the present invention to provide an electric solenoid including latching means operable each time the solenoid winding is energised and means for restoring the armature of the solenoid each time the winding is de-energised.

It is a further object of the present invention to provide an electric switch of the solenoid operated type wherein means are provided for retaining the contacts in the closed position independently of energisation of the single solenoid winding, the current through which is interrupted thereby decreasing current consumption to a very material extent. K

Thus, according to one aspect of the present invention, there is provided an electric solenoid of thesingle winding type having latching means associated with the armature thereof and operable by movement of the armature to effect latching and unlatching thereof in response to momentary energisation and subsequent momentary re-energisation respectively of the solenoid winding, means for effecting de-energisation of the solenoid winding after each momentary energisation thereof and restoring means for returning the armature to its initial position without actuation of the latching means upon each de-energisation of the-winding.

With such an arrangement, a component which has been moved as a result of an initial momentary energisaice tion of the solenoid winding will therefore remain in the new position until the winding is again energised to actuate the latching means in an unlatching sense.

In a preferred embodiment of the invention, the circuit containing the solenoid winding is automatically broken in response to actuation of the latching means following energisation of the winding, thus effecting de-energisation thereof. The solenoid is provided with associated changeover contacts which are actuated to interrupt the circuit to the solenoid winding in response to operation of the latching means, thereby effecting de-energisation of the solenoid winding, at the same time preparing a further circuit containing the solenoid winding, which when completed by operation of a switch, will connect the winding to a suitable current source to effect re-energisation thereof.

In a further embodiment of the invention, the latching means may be manually operable by means of a plunger or push button attached to the armature of the solenoid,

in the event of power failure in the energising circuit of the solenoid winding.

According to a further aspect of the present invention there is provided an electric switch including a single solenoid winding, the main contacts thereof being actuated to the closed position in response to energisation of the solenoid winding, latching means for retaining the main contacts in the closed position and associated changeover contacts located in the solenoid winding circuit and arranged to be actuated simultaneously with the operation of the latching means, such as to break the energising circuit to the solenoid Winding without opening of the main contacts of the switch.

The arrangement according to this aspect of the invention is such that in response to further energisation of the solenoid winding via the change-over contacts, the latching means is freed to allow the main contacts to be restored to the open position under the action of an associated spring.

The latching means is associated with the armature of the solenoid such that in response to successive energisation of the solenoid winding, the latching means is actuated to close and open the main contacts of the switch, and switch actuating means associated with the armature operating simultaneously with actuation of the latching means, effect opening and closing respectively of the circuit of the solenoid winding.

The electric switch-may also be manually operable through the medium of a plunger or push button attached to the armature of the solenoid, such that in the event, for example, of a power failure in the energising circuit, the main contacts and associated latching means and auxiliary contacts may be actuated by depression ofv the plunger or push button. Such a control for the switch would enable the switch to be used, for example, for the control of a lift, where the plunger, as a result of its coming into engagement with a fixed stop would actuate the main contacts of the switch to their open position to break the main electrical circuit.

However, the electric switch according to the present invention is particularly intended for operation from a remote point by means of one or more push buttons located in the solenoid winding circuit and intended to control the energisation thereof. For example, a rst normally-open push Ibutton is arranged, when actuated, to close the energising circuit to the solenoid and effect energisation thereof via the ON position of the auxiliary contacts, which are arranged within the switch casing or externally thereof. Energisation of the solenoid winding effects closure of the main contacts of the switch by movement of the armature; such movement also actuating the latching means and switching the auxiliary contacts to the OFF position, thereby effecting de-energisation of the solenoid winding. The main contacts of the switch remainclosed being held in this position by the latching mechanism, and further operation of the irst push button will not elect the main contacts of the switch or the solenoid winding in any way. A second normally-open push button is located in a line connecting the solenoid winding to a source of current, and this line also includes the contact of the auxiliary contact in its OFF position. Thus, if the second push button is actuated, the solenoid winding will again be energised to actuate the armature thereof and elfect release of the latching mechanism, opening of the main contacts of the switch and the restoration of the change-over auxiliary contact to the ON position, thus again de-energising the solenoid winding, since the first push button is in the normally-open position. The switch is thus in a position to be operated as previvously described, by depression of the lirst push button, to close the main contacts, actuate the latching mechanism and change-over the auxiliary contact thereby ensuring that whilst the main contacts are closed, no current is present in the solenoid winding circuit.

The twin push button type of control is particularly useful where one -of the two push buttons must necessarily be placed in a comparatively inaccessible position to prevent unauthorised operation. For example, the `first push button or push-on button as it will be hereinafter termed, might be always accessible, whereas the second push button or push-off button might be placed in a position in which it could not be operated except with special authority, thus preventing the switch being operated in a circuit breaking sense once the switch has been closed.

The invention will now be described by way of example only with particular reference to the acc-ompanying drawings and to the constructional features of an electric switch according to the invention, but it should be clearly understood that the invention is in no way limited to such an application, but, as previously indicated, has wider application to solenoids of the single winding type in general but it is considered that all the features of the solenoid will be clearly apparent from the constructional features of an electric switch operated by such a solenoid.

Thus, in the drawings:

FIGURE l is a sectional elevationy of the switch assernbly;

FIGURE 2 is a similar view to that of FIGURE 1, showing the solenoid and armature construction of the switch assembly;

FIGURE 3 is a section taken along the line A-A of FIGURE 1 showing a cam-operated change-over contact construction;

FIGURE 4 is a section taken along the line B-B of FIGURE l;

FIGURE 5 is a diagrammatic representation of the latching means, main Contact and change-over contacts showing the main contacts open and change-over contacts in the ON position;

FIGURE 6 shows the main contacts closed and the change-over contacts in the ON position;

FIGURE 7 shows the main contacts closed and mechanically latched and the change-over contacts in the OFF position;

'FIGURE 8 shows the main contacts closed and the change-over contacts in the OFF position;

FIGURE 9 is a perspective exploded View of the cam member for operation of the change-over contacts and i the cam surfaces of the latching means; and

FIGURE 10 is a circuit diagram illustrating the manner in which t-he solenoid winding is connected via the ON and OFF positions of the change-over contacts and the push-on and push-off buttons respectively, to an energising source of current.

Referring to FIGS. 1 and 2, the switch assembly cornprises a U-shaped yoke 1 enclosing a solenoid winding 2 wound on a former 3, the yoke 1 being secured to a back plate 4 by means of screws 5, as shown. The armature of the solenoid is shown at 6 and has secured thereto, by means of screw 7, a manually-operable control knob 8. The armature 6 is slidably mounted in bearings 9 provided on la xed bearing support member 10 located intermediate the armature 6 .and former 3. The armature 6 is provided with an axial [bore 11 within which is located a sleeve 12 provided with a shoulde-r 13 arranged to cooperate with a corresponding shoulder 14 on the armature 6 such that the sleeve 12 is carried forward by the armature 6 when the knob 8 is depressed or the solenoid winding is energised. The end wall 15 of sleeve 12 is provided with a central aperture 16 and a rod 17 is located wit-hin sleeve 12 and surrounded by a coil spring 18 held between the end wall 15 and a further sleeve m'ember 19 slidable in sleeve 12. R-od 17 is provided at one end thereof with an extension 20 `of reduced cross-sec tional area projecting through aperture 16 in end wall 15 of sleeve 12, and at the lother end, rod 17 has a further portion 21 of reduced cross sectional area passing through a contact bush moulding 22 on which is mounted the main moving contact assembly 23 of the switch. The assembly 23 includes a contact support plate 24 provided on one surface thereof with a pair of moving

contacts

25, 26, the plate 24 being bolted to the rod 17 by a bolt 27. The bush moulding 22 is provided with a flange 28 Ibehind the shoulders of which is located a leaf spring 29 biassed into contact with plate 24. Washers 30 are located intermediate ange 28 and the end of rod 17 and a further washer 31 is provided between bolt 27 and bush 22.

The fixed contacts of the main contact assembly are shown at 32, 33 in FIG. 1 and are arranged to mate with

contacts

25, 26 respectively when the knob 8 is depressed or the solenoid winding 2 energised such as to move contact assembly 23 forward as will be hereinafter described.

Contacts

32, 33 are connected to

terminals

34, 35 respectively and a coil spring 36 is provided between washer 31 and an end wall 37 of the switch assembly.

The latching mechanism for retaining

contacts

25, 32; 26, 33; in the closed position and the cam-operated change-over contacts will now be described. As shown in FIGS. l and 2, a plurality of projections 3-8 extend from sleeve 19 and a-re each provided with a curved camming surface 39 arranged to co-operate with camming surfaces 40 formed on a latching member 41 (see also FIG. 9) slidably and rotatably mounted on rod 17 within housing 42 secured to back plate 4. The

camming surfaces

39, 40 are normally out of engagement as shown in FIGS. 1 and 2, or can be in engagement dependent upon choice of length of spring 18, but are arranged Ito engage upon depression o'f knob 8 or energisation of solenoid winding 2 'to effect rotation of latching member 41 and camming surfaces -40 `secured thereto in a manner hereinafter described. A fixed stop member 43 provided with an oblique surface 44 is secured within housing 45 secured to back plate 4, as shown, and as will be described, stop member 43 is norm-ally arranged within a slot 46 formed in the latching member 41 `to prevent rotation 4of latching member 41 which is provided with cut away portions 47 for a purpose explained hereinafter. A coil spring 48 is located around tube 17 between a shoulder on latching member 41 and washelr 30 and cam member 42 is provided with projections 419 and cut-away portions 50 (FIG. accurate projections 49 and cut-away portions 50 (FIG. 9), the former being arranged to engage with a stud 51 formed on a rocker arm 52 when

contacts

25, 32 and 25, 33 are closed, and the latter being arranged to engage ril n? with the stud 51 on the rocker arm 52 when the above contacts are in the open position shown in FIGS. 1 and 2.

Referring to FIG. 3 a coil spring 53 is arranged between the rocker arm 52 and a terminal stud S4 secured to a plate 55 provided on the front surface of back plate 4 (FIGS. 1 and 2). A link 56 of electrically conducting material connects terminal stud 54 to the rocker arm 52 and a contact 57 is provided on the rocker arm 52 and arranged to rn-ate with a xed contact 58 provided on a terminal stud 59 mounted on the casing of the switch assembly.

Contacts

57 and 58 are closed when the stud 51 is in engagement with the cut-away portion 50 of cam member 42 as shown in FIG. 3 and are opened when stud 51 is in engagement with raised portions 49 of cam member 42. A further contact 60 is mounted on the end of a flexible arm 61 secured to rocker arm 52 and is arranged to mate with a contact 62 provided on a terminal Astud 63 mounted o the casing of the switch assembly,

contacts

60 and 62 being open when stud 51 is in engagement with a cut-away portion 50 of cam member 42 as shown in FIG. 3 and closed when the stud 51 is in engagement with a raised portion 49 of cam mem-ber 42. Thus

contacts

57, 58 are closed when

contacts

60, 62 are open, and vice versa and

contacts

57, 58; 60, 62 constitute the change-over contacts of the auxiliary switching means of the switch assembly. Terminal leads 64, 65-

connect studs

59, 63 to

terminals

66, 67 respectively and a further terminal point is shown at 68 in FIG. 4.

The operation of the main contacts in response to depression of knob 8 or energisation or de-energisation of solenoid winding 2, the latching of the main contacts in the closed position and the operation of the change-over contacts to effect de-energisation of the solenoid winding after the lat-ching Vmechanism has been actuated to retain the main contacts in the closed position, will now be described with particular reference to FIGS. l, 2 and 3 and in conjunction with the diagrammatic representations shown in FIGS. 5 to 8.

Assuming that the main contacts are open as shown in FIGS. l and 2, with the solenoid winding de-energized, depression of the knob or energi-sation of the solenoid winding will initially cause the armature to move axially forward, carrying with it the sleeve 12, the sleeve 19 secured thereto and the rod 17, allowing the contacts assembly 23 to move forward to close the

main contacts

25, 32; 26, 33. Since the fixed stop 43 is located within a slot 46 of the latching chamber 41, the latter is held against rotation during this initial movement of the armature 6 and contact assembly 23. The starting position is shown diagrammatically in FIG. 5 where the main contacts are shown Iin the open position with the stop member 43 located within the slot 46 of the latching member 41, and in this position, the change-over contacts are in the ON position necessary to effect energisation of the solenoid winding 2, i.e.

contacts

57, 58 are closed and contacts 60, `62 are open as shown in FIG. 3.

Following the closing of the main contacts, continued energisation of the solenoid winding or depression of knob y8, causes the armature 6 to continue its forward movement carrying with it the sleeve 19, the camming surfaces 39 of sleeve 19 co-acting with camming projections 46 of latching member 41 and pushing the latter axially until the stop member 43 is disengaged from slot 46 in lat-ching member 41. The

camming members

38, 40 are now in a position to effect rotation of latching member 41 and associated cam member 42; the forward movement having compressed coil spring 48 and flexed leaf spring 29. At this point, the change over contacts remain in the ON position with the main contacts held closed by the pressure exerted by the forward movement of the arm-ature. This intermediate position is shown in FIG. 6. The camming engagement of

surfaces

39 and 40 rotates the latching mem-ber 41 through 90, at which point the camming surfaces disengage and allow the latch- 5 ing member 41 to be restored under the bias of spring 4S to the position shown in FIG. 7 where the stop member 43 latches behind a cut away portion 47 of latching member 41 thus inhibiting rotation thereof. This position is shown in FIG. 7 where it will be seen that although the

main contacts

25, 32; 26, 33 remain closed, the changeover contacts have been actuated to the OFF position to effect deenergisation of the solenoid winding 2. This has been effected by the rotation of cam member 42 bringing a raised portion 49 thereof into contact with stud 51 to effect actuation of rocker arm 52, thereby `moving contact 57 away from contact 58 and closing contacts 6), 62. Since the change-over contacts are located in the solenoid winding circuit, the opening of

contacts

57, 58 will effect deenergisation of the solenoid winding 2, but since the stop member 43 is located within the cutaway portion 47 of latching member 41, the

main contacts

25, 32; 26, 33, are held latched in the closed position as shown in FIG. 7, without requiring that the solenoid remain energised as in prior known arrangements.

Referring to FIG; 10, the change-over contacts are shown at A and B, with the moving contact thereof in the A or ON position, which is connected to a terminal of a current source via the push-on button 69 previously referred to. On depression of push-on button 69, the solenoid winding 2 will be energised via the ON position (A) of ythe change-over contacts and lead 70, to effect closure of the

main contacts

23, 32, 33 and operation of the latching mechanism as above described, such that the change-over contacts are changed to the OFF or B position, to disconnect the solenoid winding from the energising source of current. Further depression of push-on button 69 will not affect the switch contacts in any manner. A further push button 71 (the push-off button hereinbefore -referred to) is located in the line connected to the a terminal of the current source. Thus, when the change-over contacts have been actuated to the OFF (B) position, the solenoid winding 2 may be reenergised by depression of push-off button 71 to open the main contacts and restore the change-over contacts to the ON position as will be hereinafter described.

Energisation of solenoid winding 2 or depression of knob 8 when the contacts are in the position shown in FIG. 7, will cause the armature to move forward again carrying with it sleeve 19 whose camming surfaces 39 will engage camming surfaces 40 of latching member 41. Initially the rotation of latching member 41 will be inhibited since the stop member 43 is latched within the cut-away portions 47 of latching member 41 but the continued forward movement of sleeve 19 will cause the lat-ching member 41 to be pushed forward by the engagement of camming surfaces 39, K40, and eventually disengage the stop member 43 from the cut-away portions 47 of latching member 41. This position is shown in FIG. 8 and the latching member 41 will now be Ifree to rotate by engagement of the respective camming surfaces carrying with it the cam `member 42, bringing a cut away surface 50 thereof opposite the stud 51 (FIG. 3). The

contacts

57, 58; `60, 62, will be restored to their initial positions shown in FIG. 3 and the latching member 41 will be restored to the position shown in FIG. 5 under the action of springs 29 and 48 where the stop member 43 once again engages in the slot 46 in the latching member 41 to inhibit rotation thereof. In this position of the switch, the main contacts have been opened and the change-over contacts restored to the ON position (position A of FIG. l0), such that the solenoid winding can be re-energised on depression of push-on button 69, if necessary, to once again close the main contacts of the switch.

Such a switch as has been hereinbefore described can be used as an isolation switch or alternatively as a limit switch in addition to its other various applications and as previously explained can be energised and released electrically or can be manually operated if the power source fails.

Such a switch is suitable for D.C. or A.C. operation and in the case of A.C. being used such a switch, due to the fact that the winding is only energised for a short period, avoids the noise inherent in such switches due to pulsations of the energising current setting up chattering of the armature. The switch cannot be released by means of subsequent actuation of the push-on button once the change-over contacts have been changed to the OFF position and the main contacts mechanically latched and cannot be energised ON by means of the push-off button. If necessary the switch may be energised electrically and released manually -or vice versa or energised and released electrically by means of one or more external controlling circuits.

It will be appreciated that the invention is susceptible of considerable modification and is not to be deemed limited to the particular features described by way of example only,

For instance, although the features of an electric switch have been particularly described and the operation thereof from a remote point by means of the push-on and push-off buttons, it will be clear that the solenoid when used to effect actuation of any component associated with the armature thereof, can be similarly operated from a remote point by means of such buttons in conjuction with change-over contacts located in the winding circuit.

What We claim is:

1. An electric solenoid of the single winding type having a movable armature and latching means movable in response to movement of said armature to effect latching and unlatching thereof in response to momentary energization and subsequent momentary re-energization respectively of the solenoid winding, means for effecting de-enerigization of the solenoid winding after each momentary energization thereof and restoring means for returning the armature to its initial position without actuation of the latching means upon each de-energization of the winding, wherein the latching means includes a stop member, fixedly mounted `within a casing of the solenoid, camming means arranged to move with movement of the armature, a rotatable latching member provided with camming surfaces anda slot within which the stop member is normally located to inhibit rotation of the latching member, which latter member is provided with a plurality of cut-away portions, the arrangement being such that in response to energisation of the solenoid winding, the armature moves forward carrying forward the camming means which coact with the camming surfaces of the latching member, initially pushing the latching member forward until the latter is disengaged from the stop member, following which rotation of the latching member is effected by cooperation of the camming means and camming surfaces of the latching member, until the stop member latches within a cut-away portion of the latching member to inhibit rotation thereof.

2. An electric switch comprising a solenoid Winding and having an armature to be .actuated in response to solenoid winding energization, contact means movable by said armature to a closing position, latching means responsive to movement of said armature and comprising elements to effect latching of said contact means in closing position and to effect subsequent unlatching of said contact means, in response, respectively, to momentary energization and -subsequent momentary re-energization of the solenoid winding, de-energizing means actuated by said latching means to effect de-energization of the solenoid winding after each momentary energization thereof, return means for returning the armature to an initial position subsequent to de-energization, a cam member restrained to reciprocal movement movable by said armature, wherein the latching means comprises a fixed stop member and a rotatable latching member connected to said contact means and provided with camming surface and having a slot within which the stop member is initially located to prevent rotation of said latching member,

said latchin-g member being provided with at least one cutaway portion having edges engageable by said cam member, whereby energization of the solenoid winding actuates the armature to cause the cam member to engage the camming 4surface of the latching member to initially translate the latching member until the slot thereof is disengaged from the stop member, followed by rotation of the latching member effected by coaction of said cam member and the camming surface of the latching member until the stop member engages within said cut-away portion of the latching member to preclude further rotation thereof, bias means for effecting partial return translation of said latching member so that said stop member has partial entry into said slot, said latching member being held against full reverse translation by engagement of said latching member in said cut-out portion whereby to latch said contact means in closing position, said solenoid winding being then de-energized, and said armature being then in said initial position, whereby a subsequent energization of said `solenoid winding actuates said armature to effect engagement of said cam member with said cam surface to initially translate and then rotate said latching member, said latching member to effect release of said latching member from said stop member and permit full reverse translation of said latching member.

3. An electric switch as set forth in claim Z, said deenergizing means comprising a pair of switches, said actuating means comprising a cam connected to said latching member, whereby when one switch is open the other is closed, responsive to rotation of said latching member, said switches being connected to effect respective current paths to said solenoid winding so that energization of said solenoid winding can be initially effected via one switch whence rotation of said latch member opens said one switch to de-energize said `solenoid winding and closes the other switch to condition said solenoid winding for reenergization via said other switch.

4. An electric switch comprising a solenoid winding, main contacts actuatable in response to energization of said solenoid winding to a closing or opening position, actuatable latching means operatively connected to said main contacts and comprising members for retaining a closing position of said main contacts upon energization of said solenoid winding, a pair of switches each connected in series with said solenoid winding, means connected to said latching means for actuating said switches by actuation of said latching means to either opening or closing position of said main contacts whereby one switch is closed and the other open at either of said positions, so that said solenoid winding may be initially energized through one of said switches by said latching means when said latching means is in initially non-latching position and said solenoid winding is de-energized by opening of said switch by said latching means when said latching means is subsequently in latching position, the other of said switches being then closed to condition said solenoid winding for re-energization.

5. A solenoid switch comprising a solenoid winding, an armature, main contact means, means for moving said main contact means into a closing position by said armature upon energization of said solenoid winding, a latch member reciprocally movable by said armature when moving said main contact means is moved to .a closing position, latch means coacting with said latch member to latch it in a predetermined position to which it has been reciprocated, said latch member being connected to said main contact means to hold said main contact means in lclosing condition at that time, said latching member being rotatively mounted, and means for effecting rotation of said latching member substantially at the time said main contact means have been moved to closing position, means for releasing said latching member for reverse reciprocal movement to permit opening of said main contact means and for effecting rotation of said latching member substantially at that time, and a pair of switches operable by said latching member and in response to rotation thereof, and being connected to said solenoid Winding, one switch being closed to condition said solenoid for energization when said main IContact means is in open position, and the other switch being closed to condition said solenoid Winding for energization when said main contact means are in closing position, and means whereby said switches are alternatively operated to open and closed positions by sequential rotational movement of said latching member.

References Cited by the Examiner UNITED STATES PATENTS Durdin 200-111 Wescott 200-111 Wilms et al. 200-104 X Bordelon 20G-87 X Zipper 317-192 X Keirans 20D- lll X Whinery 200-137 X BERNARD A. GLHEANY, Primary Examiner.

T. D. MACBLAIN, Assistant Examiner.

UNITED STATES PATENT OEEICE CERTIFICATE OF CORRECTION Patent No 3 ,V290 ,631 December 6, 1966 Victor Bedggood et al.

r appears in the above numbered pat- It is herebj)T certified that erro tters Patent should read as ent requiring correction and that the said Le corrected below.

In the heading to the printed specification, line 5, for "assignors to Albright (Engineers) Limited, read assignors of one-half to Albright (Engineers) Limited,

Signed and sealed this 24th day of October 1967.

(SEAL) Attest:

EDWARD J BRENNER Commissioner of Patents Edward M. Fletcher, Jr.

Attesting Officer

Claims

1. AN ELECTRIC SOLENOID OF THE SINGLE WINDING TYPE HAVING A MOVABLE ARMATURE AND LATCHING MEANS MOVABLE IN RESPONSE TO MOVEMENT OF SAID ARMATURE TO EFFECT LATCHING AND UNLATCHING THEREOF IN RESPONSE TO MOMENTARY ENERGIZATION AND SUBSEQUENT MOMENTARY RE-ENERGIZATION RESPECTIVELY OF THE SOLENOID WINDING, MEANS FOR EFFECTING DE-ENERGIZATION OF THE SOLENOID WINDING AFTER EACH MOMENTARY ENERGIZATION THEREOF AND RESTORING MEANS FOR RETURNING THE ARMATURE TO ITS INITIAL POAITION WITHOUT ACTUATION OF THE LATCHING MEANS UPON EACH DE-ENERGIZATION OF THE WINDING, WHEREIN THE LATCHING MEANS INCLUDES A STOP MEMBER, FIXEDLY MOUNTED WITHIN A CASING OF THE SOLENOID, CAMMING MEANS ARRANGED TO MOVE WITH MOVEMENT OF THE ARMATURE, A ROTATABLE LATCHING MEMBER PROVIDED WITH CAMMING SURFACES AND A SLOT WITHIN WHICH THE STOP MEMBER IS NORMALLY LOCATED TO INHIBIT ROTATION OF THE LATCHING MEMBER, WHICH LATTER MEMBER IS PROVIDED WITH A PLURALITY OF CUR-AWAY PORTIONS, THE ARRANGEMENT BEING SUCH THAT IN RESPONSE TO ENERGISATION OF THE SOLENOID WINDING, THE ARMATURE MOVES FORWARD CARRING FORWARD THE CAMMING MEANS WHICH COACT WITH THE CAMMING SURFACES OF THE LATCHING MEMBER, INITIALLY PUSHING THE LATCHING MEMBER FORWARD UNTIL THE LATTER IS DISENGAGED FROM THE STOP MEMBER, FOLLOWING WHICH ROTATION OF THE LATCHING MEMBER IS EFFECTED BY COOPERATION OF THE CAMMING MEANS AND CAMMING SURFACES OF THE LATCHING MEMBER, UNTIL THE STOP MEMBER LATCHES WITHIN A CUT-AWAY PORTION OF THE LATCHING MEMBER TO INHIBIT ROTATION THEREOF.