Patent ID: 7201161

Claim:
A compound spring-loaded archery bow comprising: a rigid bow frame comprising a rigid central riser, a rigid upper limb, and a rigid lower limb; the rigid central riser with a handgrip and an arrow rest; the central riser having an upper end portion and a lower end portion; the rigid upper limb extending upward from the upper end portion of the central riser; the rigid lower limb extending downward from the lower end portion of the central riser; an upper cam means mounted on an upper end portion of the rigid upper limb and a lower cam means mounted on a lower end portion of the rigid lower limb; a bowstring secured to extending between the upper and lower cam means which actuates the upper and lower cam means when the bowstring is drawn; the bowstring having an initial undrawn position; the rigid upper limb being a tubular member and containing an upper spring assembly for applying tension to the bowstring through the upper cam means when the upper cam means is actuated by drawing the bowstring from the initial undrawn position; the upper spring assembly comprising an upper compression coil spring and an upper connector means connecting the upper compression spring to the upper cam means so that when the upper cam means is actuated by drawing the bowstring, the upper compression spring of the upper spring assembly is increasing compressed as the bowstring is drawn to exert forces of increasing magnitude on the bowstring to increase the tension in the bowstring; the upper cam means has a preset unactuated position where the upper spring assembly does not exert forces on the bowstring through the cam means; the rigid lower limb being a tubular member and containing a lower spring assembly for applying tension to the bowstring through the lower cam means when the cam means is actuated by drawing the bowstring from the initial undrawn position; the lower spring assembly comprising a lower compression coil spring and a lower connector means connecting the lower compression spring to the lower cam means so that when the lower cam means is actuated by drawing the bowstring, the lower compression spring of the lower spring assembly is increasing compressed as the bowstring is drawn to exert forces of increasing magnitude on the bowstring to increase the tension in the bowstring; the lower cam means has a preset unactuated position where the lower spring assembly does not exert forces on the bowstring through the cam means; and synchronization means interconnecting the upper and lower cam means so that the upper and lower cam means are actuated to substantially the same degree when the bowstring is drawn from the initial undrawn position.