Abstract: A method and a bale wrapping device for wrapping a bale. The method includes receiving a bale at a bale moving ramp device of the bale wrapping device. The bale on the bale moving ramp device is moved through a bale wrapping frame. The breathable sheet of wrapping material is applied on the bale to wrap the bale as the bale passes through the bale wrapping frame, and a roller on the bale wrapping frame holds a roll of the breathable sheet of wrapping material.

Abstract: The present invention is directed generally to a buck converter that achieves zero voltage switching (ZVS). According to various embodiments, the buck converter comprises a ZVS circuit for storing reverse recovery current from the diode of the buck converter and using the energy from the reverse recovery current to discharge parasitic capacitance of the primary switch of the buck converter prior to turn-on of the primary switch such that the primary switch turns on with substantially zero voltage across the switch. The ZVS circuit may comprise a capacitor, an auxiliary switch connected in series with the capacitor, and an auxiliary inductor connected in parallel with the series-connected capacitor and auxiliary switch.

Abstract: A network device for interconnecting computer networks, the device including a bridge having a plurality of ports through which network communications pass to and from the bridge, the bridge also including a first interface enabling a user to partition the plurality of bridge ports into a plurality of groups, wherein each group represents a different virtual network, wherein the bridge treats all ports within a given group as part of the virtual network corresponding to that group and the bridge isolates the virtual networks from each other, whereby any communications received at a first port of the bridge are directly sent by the bridge to another bridge port only if the other bridge port and the first bridge port are part of the same group.

Abstract: A network device for interconnecting computer networks, the device including a bridge having a plurality of ports through which network communications pass to and from the bridge, the bridge also including a first interface enabling a user to partition the plurality of bridge ports into a plurality of groups, wherein each group represents a different virtual network, wherein the bridge treats all ports within a given group as part of the virtual network corresponding to that group and the bridge isolates said virtual networks from each other, whereby any communications received at a first port of the bridge are directly sent by the bridge to another bridge port only if the other bridge port and the first bridge port are part of the same group.

Abstract: A boost converter power supply circuit uses energy from a diode recovery current which flows in the blocking diode at diode commutation to discharge a capacitance associated with the main switch of the boost converter in order to achieve zero voltage switching. The diode recovery current energy is initially captured in an inductor, is then transferred to a capacitor, and is then transferred back to the inductor prior to the main switch being switched on. In accordance with another embodiment, a control circuit for controlling a boost converter to achieve power factor correction is disclosed which does not use a high gain input current feedback loop. The control circuit responds relatively quickly to output load changes, thereby overcoming disadvantages of prior art control circuits. Because the control circuit does not require an X-Y multiplier, the control circuit lends itself to realization in integrated circuit form.

Abstract: A two switch, DC/DC converter provides sufficient inductive energy storage at the termination of the "on" period of each switch to alter the charge on the intrinsic and stray capacitance of the combination of switches producing zero voltage across the alternate switch prior to its turn on. A short dead-band between the turn on pulses provided by the control circuit allows time for this transition. Thus the energy stored in the capacitance of the switches is returned to the source and load rather than being dissipated in the switching devices. This greatly improves the efficiency of the converter particularly when operating at high frequency. The unique topology of the converter provides other new and useful characteristics in addition to zero voltage switching capability such as operation as constant frequency with pulse-width-modulation for regulation, quasi-square wave output current, and the ability to integrate the magnetic elements with or without coupling.

Abstract: A two switch, DC/DC converter provides sufficient inductive energy storage at the termination of the "on" period of each switch to alter the charge on the intrinsic and stray capacitance of the combination of switches producing zero voltage across the alternate switch prior to its turn on. A short dead-band between the turn on pulses provided by the control circuit allows time for this transition. Thus the energy stored in the capacitance of the switches is returned to the source and load rather than being dissipated in the switching devices. This greatly improves the efficiency of the converter particularly when operating at high frequency. The unique topology of the converter provides other new and useful characteristics in addition to zero voltage switching capaibility such as operation at constant frequency with pulse-width-modulation for regulation, quasi-square wave output current, and the ability to integrate the magnetic elements with or without coupling.

Abstract: A circuit is provided for providing a regulated d.c. output of a substantially high output current magnitude from an unregulated single or polyphase a.c. input source. Regulation is provided by a single feedback circuit interacting with a plurality of ferroresonant transformers connected in parallel to a single phase source, singly on each phase or a polyphase source, or interconnected in the known Scott T connection on a three phase source. Regulation is accomplished with thyristor switches which are synchronized with the input phase of each transformer.