Patent GB-875366-A (GB)
Title: New or improved cycle-driving mechanism
IPC: B62M1/24
Filed: 1956-09-05
Abstract: 875,366. Treadle-propelled cycles. COULSON, L. D. Dec. 4, 1957 [Sept. 5, 1956], No. 27180/56. Class 136(2). In a cycle driving-mechanism comprising a pair of pedals A<SP>1</SP>, A<SP>2</SP> mounted for reciprocating movement on non-swingable arms B<SP>1</SP>, B<SP>2</SP> which coact with guide means D to constrain the pedals to move approximately vertically in a substantially straight line, the pedals are drive coupled to driving wheels N<SP>1</SP>, N<SP>2</SP> (Fig. 1) having uni-directional clutch devices which act in applying a one-way drive to a member M, the clutch devices being so arranged that depression of either pedal turns the related driving wheel N<SP>1</SP> or N<SP>2</SP> to apply. a drive to the driven member M, the pedals being interconnected to cause one to rise as the -other descends, the driven member M being drive connected to a road wheel of the cycle. Chains Z\ Z<SP>2</SP>, Z<SP>3</SP>, Z<SP>4 </SP>connect the pedals to the driving wheels N<SP>1</SP>, N<SP>2</SP> (Fig. 10). The pedals are connected by the arms B<SP>1</SP>, B<SP>2</SP> to runners . C<SP>1</SP>, C<SP>2</SP> (Fig. 3) which are guided for vertical reciprocation in guides D secured to the cycle frame. The guides comprise two spaced apart inwardly opening outer channel-section members D<SP>1</SP>, with a centre I-section member D<SP>2</SP> interposed between them. The runners are fitted with bearings C' which engage both an outer member D<SP>1</SP> and one side of the inner member D<SP>2</SP>. A compression spring D<SP>3</SP> is provided at the lower ends of the guides for dampening sudden downward movement of a pedal. The chains Z\ Z<SP>4</SP> pass over sprocket wheels Y<SP>1</SP>, Y<SP>2</SP> mounted on the centre guide D. A link AA connects one end of the chain Z' with the chain Z<SP>3</SP>, the other end of chain Z<SP>4</SP> being joined to chain Z<SP>2</SP> by link AB. The links are designed so that the ends of the respective chains to which they are connected are turned through 90 degrees relative to each other to enable the. sections of chain to pass freely over. their respective sprocket wheels Y<SP>1</SP>, Y<SP>2</SP>, N<SP>1</SP>, N<SP>2</SP>. The opposite end of chain Z<SP>2</SP> is connected to the top runner C<SP>1</SP> and the opposite end of chain Z<SP>3</SP> is connected to  runner C<SP>2</SP>, the chain Z<SP>1 </SP>being joined to the bottom. of runners C<SP>1</SP>, C<SP>2</SP>. One driving wheel N<SP>1</SP> or N<SP>2</SP> is positively operated during the  depression of one pedal whilst the other driving wheel is idling. A uni-directional clutch mechanism L comprises the sprocket wheels N<SP>1</SP>, N<SP>2</SP> which have interposed between them the sprocket wheel M by which the drive from the two pedals on their associated sprocket wheels is transmitted as a continuous drive to the rear wheel of the cycle. The drive is transmitted from the sprocket wheel M by way ot a chain V to a sprocket mechanism X<SP>1</SP>, X<SP>2</SP> mounted on a swingable arm Q. The sprocket mechanism X<SP>1</SP>, X<SP>2</SP> is connected to the rear wheel of the cycle by a chain W (Fig. 10). The sprocket wheels N<SP>1</SP>, N<SP>2</SP> are carried by housings P<SP>1</SP>, <SP>p2</SP> accommodating the one-way drive mechanism, the housings being connected by way of cushioning members 5 to the sprocket wheel M-