Patent GB-1267849-A (GB)
Title: A case with a cover latching device for an electrically operated device
Inventor: DUPUIS G-L
IPC: H01H9/22
Filed: 1969-12-23
Abstract: 1,267,849. Safety cover lock for the casing of electrical apparatus. BURROUGHS CORP. 23 Dec., 1969 [6 Jan., 1969], No. 62687/69. Headings E2A and E2B. [Also in Division H2] A case with a cover latching device for an electrically operated apparatus, the case having a first aperture formed in a base portion thereof through which the connectors of an electrical supply cord are connectable with the apparatus, the cover latching device comprising: (a) slidably coupleable first latching means interiorly fixed at single complementary sides of the cover and the base portion, and (b) rockably coupleable second latching means interiorly fixed at single complementary sides of the cover and the base portion opposite the sides at which the first latching means is attached, the second latching means being cooperable with the first latching means to lock the cover of the case to the base portion, the second latching means including an apertured slide cooperably associated with the first aperture of the base portion to permit the connections of the electricity supply cord with the electrically operated apparatus when the cover is locked in place by the first and second latching means, and being also blockingly associated with the first aperture of the base portion to prevent the connection of the electricity supply cord with the apparatus when the cover is displaced or removed from the base portion. The rockably coupleable latching means at the back side of the casing comprises two cam hooks 51 and 53 both of which are connected to the slideable member 69 via the double shouldered screws 55 attached to the base and sliding in slots 70 on 69 and studs 63 on the cam hooks cooperating with slots 75 on 69, and foot members 43 having studs 47 which engage the arcuate slot 61 of the cam segment 59. To attach the cover 21 to the base portion 23 a pair of transverse rods 27 of the bifurcated members 25 are slid into a pair of slots 39 at the front side of the casing, the cover 21 as shown in Fig. 4 is tilted in an anticlockwise direction so that the studs 47 of the second latching means contact the arcuate slot 61 causing the cam hooks 51, 53 to rotate clockwise and anticlockwise respectively which causes the slideable member 69 to move leftwards in Fig. 7. At the point in the rotation of the cam hooks 51, 53 where the spring 65 moves below the horizontal plane of the shouldered screws 55 contraction of the spring completes ths rotation of the cam hooks and engages the studs 47 under the locking surfaces 62 of the cam hooks. In this position when the cover 21 is locked to the base 23 the slot 77 in the slideable member 69 coincides with the slot 79 in the base 23 and thus an electrical supply plug can be inserted therethrough. To remove the cover 21 from the base 23 the electrical plug must be removed and the tab 81 which is accessible from outside the base 23 is moved rightwards in Fig. 8, moving the studs 47 out of contact with the locking surfaces 62 at which point removal of the cover 21 is the reverse process of its assembly.