Abstract: This invention describes the use of a polycarbonate-siloxane block copolymer in the fabrication of various components, especially those subject to repeated impact, for devices such as baseball and softball bats. This material has been shown to possess excellent impact fatigue resistance, a benign mode of failure, and an ability to maintain its shape following impact that was not observed in any other tested polymers.

Abstract: A baseball or softball bat configured to allow the removal and replacement of a barrel assembly of the bat for enabling selection of a barrel having particular performance characteristics or simply if the barrel is damaged. Alternatively, the barrel assembly may be selectively changed to meet certain regulation requirements. In particular, the barrel assembly or other bat component can also include a ballast for selectively providing the ball bat with a particular weight. The ballast can be provided as a tube of thin film in the barrel assembly. The thin film ballast tube also forms a tamper resistant shield to inhibit modification of components inside the barrel section. In one aspect, one or more components of the ball bat can be provided as a kit. In one aspect, the kit may be a barrel assembly kit. In another aspect, the ball bat can be made by forming and assembling the components.

Abstract: A baseball or softball bat configured to allow the removal and replacement of the barrel section of the bat if the barrel is damaged or simply for enabling selection of a barrel having particular performance characteristics. Alternatively, the barrel may be selectively changed to meet certain regulation requirements. In one aspect, one or more components of the ball bat can be provided as a kit. In another aspect, the ball bat can be made by forming and assembling the components simply and inexpensively. Exemplary embodiments include a center tube or handle, a transition, and a barrel some or all of which can be separably combined during assembly.

Abstract: A ball bat configured to allow the removal and replacement of a barrel assembly for enabling selection of a barrel having particular performance characteristics or if the barrel is damaged. The barrel assembly may be selectively changed to meet certain regulation requirements. A bat component can also include a ballast for selectively providing the ball bat with a particular weight. The ballast can be provided as a tube of thin film in the barrel assembly. The thin film ballast tube also forms a tamper resistant shield to inhibit modification of components inside the barrel section. One or more components of the ball bat can be provided as a kit. The kit may be a barrel assembly kit. The ball bat can be made by forming and assembling the components simply and inexpensively. Some or all of the components can be separably combined during assembly.

Abstract: A baseball or softball bat configured to allow the removal and replacement of a barrel assembly of the bat for enabling selection of a barrel having particular performance characteristics or simply if the barrel is damaged. Alternatively, the barrel assembly may be selectively changed to meet certain regulation requirements. In particular, the barrel assembly or other bat component can also include a ballast for selectively providing the ball bat with a particular weight. The ballast can be provided as a tube of thin film in the barrel assembly. The thin film ballast tube also forms a tamper resistant shield to inhibit modification of components inside the barrel section. In one aspect, one or more components of the ball bat can be provided as a kit. In one aspect, the kit may be a barrel assembly kit. In another aspect, the ball bat can be made by forming and assembling the components simply and inexpensively.

Abstract: A baseball or softball bat configured to allow the removal and replacement of the barrel section of the bat if the barrel is damaged or simply for enabling selection of a barrel having particular performance characteristics. Alternatively, the barrel may be selectively changed to meet certain regulation requirements. In one aspect, one or more components of the ball bat can be provided as a kit. In another aspect, the ball bat can be made by forming and assembling the components simply and inexpensively. Exemplary embodiments include a center tube or handle, a transition, and a barrel some or all of which can be separably combined during assembly.

Abstract: A baseball or softball bat configured to allow the removal and replacement of a barrel assembly of the bat for enabling selection of a barrel having particular performance characteristics or simply if the barrel is damaged. Alternatively, the barrel assembly may be selectively changed to meet certain regulation requirements. In particular, the barrel assembly or other bat component can also include a ballast for selectively providing the ball bat with a particular weight. The ballast can be provided as a tube of thin film in the barrel assembly. The thin film ballast tube also forms a tamper resistant shield to inhibit modification of components inside the barrel section. In one aspect, one or more components of the ball bat can be provided as a kit. In one aspect, the kit may be a barrel assembly kit. In another aspect, the ball bat can be made by forming and assembling the components simply and inexpensively.

Abstract: A method of tuning a bat includes estimating a ball-bat interaction time, Ti, of an impact between a ball and the bat and tuning at least one desired mode of vibration in the bat produced by the impact. The desired mode of vibration is tuned by selecting properties of the bat so that the desired mode of vibration has a period approximately equal to 4/3 Ti. When a mode of vibration is so tuned, the energy the vibration transfers to a batted ball is optimized. A tuned bat has one or more of the desired modes that is approximately equal to 4/3 Ti, giving the bat a desirable bat performance factor and a desirable level of durability. Typically, the first hoop mode of vibration is given first priority during tuning of the bat. However, other modes of vibration, such as an axial bending mode of vibration may also be tuned to have a period approximately equal to 4/3 Ti.

Abstract: A method of tuning a bat includes estimating a ball-bat interaction time, Ti, of an impact between a ball and the bat and tuning at least one desired mode of vibration in the bat produced by the impact. The desired mode of vibration is tuned by selecting properties of the bat so that the desired mode of vibration has a period approximately equal to 4/3 Ti. When a mode of vibration is so tuned, the energy the vibration transfers to a batted ball is optimized. A tuned bat has one or more of the desired modes that is approximately equal to 4/3 Ti, giving the bat a desirable bat performance factor and a desirable level of durability. Typically, the first hoop mode of vibration is given first priority during tuning of the bat. However, other modes of vibration, such as an axial bending mode of vibration may also be tuned to have a period approximately equal to 4/3 Ti.

Abstract: A method of tuning a bat includes estimating a ball-bat interaction time, Ti, of an impact between a ball and the bat and tuning at least one desired mode of vibration in the bat produced by the impact. The desired mode of vibration is tuned by selecting properties of the bat so that the desired mode of vibration has a period approximately equal to 4/3Ti. When a mode of vibration is so tuned, the energy the vibration transfers to a batted ball is optimized. A tuned bat has one or more of the desired modes that is approximately equal to 4/3Ti, giving the bat a desirable bat performance factor and a desirable level of durability. Typically, the first hoop mode of vibration is given first priority during tuning of the bat. However, other modes of vibration, such as an axial bending mode of vibration may also be tuned.

Abstract: A spoke system includes at least three rim pivots, at least three hub pivots, and plural shafts each extending along a substantially linear path between a rim pivot and a hub pivot, each path being substantially aligned with the center of a rim pivot and the center of a hub pivot. Each shaft includes an integral rim end forming a loop around a rim pivot and an integral hub end forming a loop around a hub pivot. The present invention also includes a tensioning system for biasing the inner vertices away from the outer vertices, thereby tensioning the continuous spoke. The path of each shaft may be substantially aligned with the center of a rim pivot and the center of a hub pivot so that a tension along the length of the shaft will not produce a moment about the rim pivot or the hub pivot.