Patent GB-989941-A (GB)
Title: Improvements in and relating to dry-shaving apparatus
IPC: B26B19/38
Filed: 1964-01-17
Abstract: 989,941. Dry shavers. PHILIPS ELECTRONIC & ASSOCIATED INDUSTRIES Ltd. Jan. 17, 1964 [Jan. 22, 1963], No. 2180/64. Heading B4B. A dry shaver having a shaving head 2 which is hinged to the housing 9 of the shaver by means of a shaft and which has at least one shear plate and a flat peripheral portion which, when the shaving head is in the closed position, engages the rim of that part of the housing which supports the shaving head is characterized in that the flat peripheral portion of the shaving head extends over the shaft to meet the rim of the housing so that the shaft lies on the inner side of the flat peripheral portion of the shaving head and in that the shaft is displaceable under the action of a spring over a limited distance in a direction at right angles to the axis of the shaft. As shown in Fig. 1, shaft 5 is supported by a member 11 which is accommodated in a cavity 12 behind the wall 13 of the housing 9, the member 11 being movable in the cavity under the action of a spring 10 which exerts a pressure on the member 11 in a direction away from the part 7 of the housing rim, the pressure being taken in the closed position of the shaving head, on the part 8 of the housing rim through a shoulder 17 forming part of a catch 18 engaged by a spring 19 to hold the shaving head in the closed position. The spring 19 is disengaged from the catch 18 by pressing a push button 20 and this allows a torsion spring (not shown) surrounding the shaft 1 to lift the shaving head sufficiently to free the shoulder 17 from the part 8 of the housing rim. The shaving head is then shifted to the right by the spring 10 until the member 11 abuts a wall 16. This movement is sufficient to bring the part 5 of the rim of the shaving head out of engagement with the part 7 of the housing rim so that the shaving head is free to swing into the open position (Fig. 2) under the action of the torsion spring. In this position, the chamber 4 beneath the head can be cleaned out by blowing. The inner end of the push button 20 is bifurcated, Fig. 1a, and when the shaving head is in the closed position, the catch 18 lies between the limbs of the bifurcation. These limbs push the spring 19 away from the catch 18 when the push button is pressed, and as soon as the spring is disengaged from the catch an inclined surface 28 on the push button between the limbs thereof abuts a corresponding surface 29 on the catch and co-operates to lift the shoulder 17 out of engagement with the housing rim. When the shaving head is again pressed down into the closed position, the inclined surface 29 slides across the inner edge of the part 8 of the housing rim and the head is thereby shifted to the left against the action of the spring 10 until the shoulder 17 snaps behind the rim part 8. The transverse part of the spring 19 slides upon inclined face 30 on the end of the catch 18 and snaps over the lip 31 of the catch to engage the upper surface 32 thereof and urge the shaving head into the fully closed position. In a modification, Fig. 3, the member 11 is mounted vertically in a groove 21 in the wall 13 of the housing and has a tag 24 which is urged downwardly by a spring 22. When the spring 19 is disengaged from the catch 18, the shaving head is immediately swung up into the open position by the torsion spring which surrounds the shaft 1. During this movement, the rim part 5 moves across the rim part 7 towards the inner edge thereof and at the same time the shaft 5 rises slightly taking with it the member 11 against the action of the spring 22.