1,099,511. Construction locks. B. E. ETTER. Jan. 21, 1965 [Aug. 21, 1964], No. 2808/ 65. Heading E2A. A locking device is characterised by plate means, a housing 45 mounted on the plate means, a control bar 179 movably mounted in the housing, movable locking means mounted in the housing and adapted to prevent movement of the control bar, a dial 91 movably mounted on the plate means, a spring 87 movably connecting the plate means to the dial to resist the movement of the dial in one direction, the spring yieldably holding the dial m a predetermined position and returning the dial to said predetermined position whenever a displacing force on the dial has been removed, the dial and the movable locking means being connected so that the predetermined movement of the dial in a plurality of separate movements in one direction will position the movable locking means to permit movement of the control bar, an operating handle 289 movably connected to said plate means and having a latch bolt assembly 209 connected thereto, said control bar preventing the handle from actuating the latch bolt assembly when said movable locking means prevents movement of said control bar, and means for resetting the movable locking means. In the construction shown the plate means consists of two plates 15, 17, the plate 15 being intended for mounting on the exterior surface of a door and the plate 17 being intended for mounting on the interior surface of the door; the plates are maintained in engagement with the door and with each other by screws such as 19, which engage tubular members 25, 27, 29 which are secured to the inner surface of plate 15. The plate 15 is provided with the out-away portions 31, 33 in its outer surface to receive the dial 91 which is of the telephone type and also the return spring 87 for the dial, the spring embracing a head portion 85 of a primary arm 79; the head portion extends through the plate 15 to secure the dial and the spring is engaged between a notch 89 in the head portion 85 and a lug 35 in the recess 33. A finger stop 105 is mounted in a slot 107 on plate 15 to limit finger movement during dialling. Secured to the plate 15 behind the dial by means of rods 39, 41 and 43 and nuts, is the housing 49. the open end of which adjacent the plates 17, is closed by a cover 171. The primary arm 79 is contained within the housing with its head portion projecting through a hole 57 in the base portion 47 and through the plate 15 and a shaft 81 of the primary arm extends along the axis of the housing and its free end portion is journalled in the cover 171 and also carries a secondary arm 155; the primary and secondary arms each have an outwardly extending arm portion 157, 83 and between these a square shaft 161. is carried on which is slidably mounted a ratchet driving finger 165 which is biassed towards the secondary arm by a spring 169. Mounted on the shaft 81 are four ratchet assemblies each of which includes a ratchet support disc 123 having a central portion 125, an integral portion 127 extending downwardly, there from and a sleeve member 129 extending outwardly from its front side and on a reduced diameter end portion of which a ratchet wheel 109 of the assembly is freely rotatable; the four ratchet wheels constitute the movable locking means. The shaft 81 passes through the sleeve members 129. Each assembly also includes a ratchet wheel return spring 121 one end portion of which engages a boss 119 of the ratchet wheel and the other end portion of which engages a hole 135 in the disc 123; return rotation of the ratchet wheels is limited by the engagement of the boss 119 with a lug 133 on the disc 123. Movement of the discs relative to the housing is prevented by the rod 43 passing through the slots 137 in each disc portion 127. Each assembly has a pawl 145 mounted on portion 127, which is biassed by a spring 151 and which engages teeth 113 of the ratchet wheel to prevent return movement of the ratchet wheel under the bias of the spring when it has been moved to a required position by the dial. The ratchet wheels are moved one at a time by the driving finger 169 upon appropriate rotation of the dial for each wheel. The driving finger is initially in a reset position between ratchet wheel 109 and primary arm 79 with surface 167 engaging ratchet lug 115 of wheel 109; the rotation of dial 91 causes finger 165 to rotate wheel 109 in a clockwise direction as shown in Fig. 5 and when the dialled position has been reached the dial return spring returns the dial and hence the driving finger to the initial position and since the ratchet wheel cannot return owing to the pawl 145, the driving finger is removed from engagement with the lug 115 and the spring 169 moves it into engagement with the lug 115 of the next ratchet wheel, the sequence being repeated until all the ratchet wheels have been moved to their dialled positions. If the correct numbers have been dialled the series of notches 117, one in each ratchet wheel, are then in alignment and the control bar 179 can then be moved to the left as shown in Fig. 5; movement has previously been prevented by engagement of lugs 181, 182, 184, 186 of the control bar with the surfaces of the ratchet wheels. The control bar is moved by a control disc 61 which has a notch in its rear surface which engages the end portion of the bar, the edges of the notch moving the bar longitudinally when the disc is rotated; when the bar is prevented from movement by abutment of the lugs against the ratchet wheels rotational movement of the control disc is also prevented by engagement of the notch and bar 179. The control disc is pivotally and slidably mounted on a tubular projection of the housing and it is coupled to the handle 289, which is an exterior handle is pivotally mounted on a bracket 249 carried by the front plate 15 with the end portion of the handle projecting through the front plate. If the end portion of the exterior handle is moved upwardly when the ratchet wheels are in the releasing positions in which the notches 117 are in alignment, the control disc is rotated through linkwork and a member 315 of the link work engages a crank 203 mounted on a spindle 199 to rotate the spindle; the spindle in turn withdraws a latchbolt of the latchbolt assembly 209 through a follower 208 which is mounted on a square section of the spindle 199. When the ratchet wheels are in looking positions rotation of the control disc 61 is prevented as - described above An outward movement of the exterior handle only compresses a spring in the linkage between the handle and the control disc so that the spindle 199 cannot be rotated. Downward movement of the end portion of the exterior handle moves a reset lever 361 which engages the ratchet driving finger 165 and moves it along the shaft 161 to its original position; as the finger 165 is moved between the primary arm 79 and the ratchet wheel nearest to it, a cam surface 371 on the lever 361 engages a cam surface 195 on a pawl tripping cam 187 and rotates the cam so that each of the pawls 145 is moved to release the ratchet wheels which then return to their original positions under their spring bias so causing the control bar 179 to engage the notch in the control disc and prevents its rotation; The control disc is normally held in engagement with the face of the housing by a cam 71 which is slidably mounted on the housing, the cam 71 however can be moved downwardly by an interior disengaging handle 267 rotatably mounted on the plate 17 and when this is done the control disc can slide away from the face of the housing and hence away from the end portion, of the control bar 179 so that the control disc can then rotate even though the ratchet wheels are in locking positions the exterior handle can then be used to withdraw the latch bolt. An interior handle 233 is rotatably mounted on the plate 17 and rotation of the handle in one direction rotates the spindle 199 to withdraw the latch bolt; this is possible since the crank 203 is only in abutment with the member 315 and its arm can move away from the member. Rotation of the interior handle 233 in the opposite direction does not rotate the shaft 199 but instead causes the movement of the reset lever 361 which moves the driving finger to its original position and releases the pawls from the ratchet wheels. In a modification instead of providing a rotatable dial as shown, a dial bar is provided which is movable vertically and which has teeth on one edge which engage a pinion connected to the primary arm to rotate it; the arrangement otherwise is identical with that previously described.