Patent GB-622361-A (GB)
Title: Improvements in or relating to tyre protecting and preserving devices
IPC: B60S1/68
Filed: 1947-11-11
Abstract: 622,361. Wheel scrapers. CARLTON, W. C. Nov. 11, 1947, No. 29957. [Class 108 (ii)] A tyre protecting and preserving device comprising an extractor or deflector blade member, and means for yieldingly holding the extractor or deflector member in operative position relative to the tyre surface to be protected, also comprises means for damping movement imparted to the extractor or deflector member by irregularities in the tyre surface or vibration of the tyre and/or associated wheel mounting. In the arrangement according to Fig. 1, a serrated extractor or deflector blade 8 which may be in any of the forms described in Specification 618,855 is adjustably secured to a plurality of supporting arms 11 which are pivotally connected to a mounting bar 14, secured to or forming part of a supporting bar 16 which is adjustably secured to the wheel suspension system. A hydraulic damping device comprising a cylinder 22, Fig. 3, filled with oil or the like, piston 23, connecting rod 24 and spring 28, is mounted on a saddle 21 carried on an extension 14a of the mounting bar. The connecting rod is coupled through a bar 25 to the arms 11, whereby the blade 8 is urged against the tyre surface by the spring, the compression of which is adjustable by means of a cylinder 27. Bleed holes 29 in the piston allow oil to flow from one side of the piston to the other when the latter moves along the cylinder due to movement of the blade against the tyre surface. In another arrangement, Fig. 4, the damping device comprises a cylinder 22<SP>1</SP> mounted on the bar 14 and carrying a spring-loaded axle 30 connected between the supporting arms 11. A vane 36 on the axle is enclosed in a fluid-tight compartment 31b of the cylinder and co-operates with a fixed vane 35. Bleed holes 36a in the vane 36, control the rotation of the axle and hence the movement, of the blade 8 against the tyre surface. The loading torque of the spring 28<SP>1</SP> may be adjusted by angular adjustment of a plate 32, having lugs 33 engageable with slots 34 formed in the end of the cylinder 22<SP>1</SP>. Either of the foregoing damping devices may be applied to an arrangement, Fig. 5 (not shown), wherein the extractor or deflector blade is carried by elongated brackets secured by links to an extension of the supporting bar 16, as described in Specification 622,362. In another arrangement, Figs. 6, 7 and 8 (not shown), the damping device comprises a length of twisted wire cable surrounded by a coil spring firmly clamped to an eye bracket at one end of the cable and freely slidable along or clamped to a screwed shank at the other end thereof, this assembly also forming a supporting arm for the deflector blade. The eye-bracket is adjustably secured to a bracket carrying the deflector blade and the shank is secured to a mounting bar carried by a screwed rod which is adjustably clamped to a supporting- bar, whereby the supporting arm may be flexed. In alternative arrangements, Figs. 9 and 10 (not shown), the cable may be replaced by a inner helical spring or either construction may be encased in a flexible sheathing. When so encased, the arms may consist of coil springs only, or othersingle resilient and/or flexible members. In arrangements applicable to lightweight vehicles, e.g. cycles, an extractor or deflector blade 8<SP>1</SP>, Fig. 11, is attached to flexible supporting arms 11d which act to damp vibratory movement of the blade 8<SP>1</SP>. In order to prevent " bouncing " the blade may be widened to accommodate the curvature of the tyre. Alternatively or additionally, a skid device may be adapted to contact the surface of the tyre not in contact with the road. In a further arrangement, Fig. 14, a clearing bar 8<SP>11</SP> is connected by resilient metal arms 11e in the form of coiled springs-to a mounting bracket 51 so that the bar 811 rests on the tyre. The arms 11e may be sheathed as described above. Skid devices may also be provided.