Abstract: A driving circuit includes a control circuit and a boost converter circuit. The control circuit receives a sense voltage associated with a direct-current (DC) source voltage, and generates a control signal with a duty cycle that varies with the sense voltage in a monotonically increasing manner. The boost converter circuit receives the DC source voltage and the control signal, thereby providing a driving current for driving light emission of a light emitting component. The driving current has a magnitude positively correlated to the duty cycle of the control signal.

Abstract: A driving circuit includes a control circuit and a boost converter circuit. The control circuit receives a sense voltage associated with a direct-current (DC) source voltage, and generates a control signal with a duty cycle that varies with the sense voltage in a monotonically increasing manner. The boost converter circuit receives the DC source voltage and the control signal, thereby providing a driving current for driving light emission of a light emitting component. The driving current has a magnitude positively correlated to the duty cycle of the control signal.

Abstract: A lamp seat includes a metal substrate having opposite first and second surfaces, first and second conductive patterns formed on the first surface, and third and fourth conductive patterns formed on the second surface and connected respectively and integrally to the first and second conductive patterns. A heat-conductive first insulating layer is disposed between the metal substrate and each of the first, second, third and fourth conductive patterns. A heat-conductive second insulating layer is formed over the first insulating layer such that corresponding parts of the first and second conductive patterns are exposed outwardly of the second insulating layer for electrical connection with positive and negative electrodes of a light emitting diode, respectively.

Abstract: A battery receptacle includes an insulative casing, positive and negative electrodes, and an interface assembly. The positive and negative electrodes have end portions disposed on the casing. The negative electrode has an end portion disposed on the casing. The interface assembly is disposed on the casing, and includes an insulative body, anode and cathode terminals, a contact element, and an insulating protrusion. The anode terminal projects from the insulative body, and is in electrical contact with the end portion of the positive electrode. The cathode terminal is provided on a periphery of the insulative body. The contact element is in electrical contact with the cathode terminal, projects from the insulative body, and is in electrical contact with the end portion of the negative electrode. The insulating protrusion is provided on the insulative body, and abuts against the end portion of the positive electrode.

Abstract: A multiple-pair-terminal battery receptacle includes a casing, first and second anode terminals, first and second conductive members, and first and second cathode terminals. The first anode terminal is mounted on the casing. The first conductive member is disposed in the casing and is coupled to the first anode terminal. The second anode terminal is mounted removably on the casing and engages detachably the second end portion of the first conductive member. Each of the first and second cathode terminals is mounted on the casing. The second conductive member interconnects the first and second cathode terminals.

Abstract: A lamp seat includes a metal substrate having opposite first and second surfaces, first and second conductive patterns formed on the first surface, and third and fourth conductive patterns formed on the second surface and connected respectively and integrally to the first and second conductive patterns. A heat-conductive first insulating layer is disposed between the metal substrate and each of the first, second, third and fourth conductive patterns. A heat-conductive second insulating layer is formed over the first insulating layer such that corresponding parts of the first and second conductive patterns are exposed outwardly of the second insulating layer for electrical connection with positive and negative electrodes of a light emitting diode, respectively.

Abstract: A focus-adjustable LED flashlight includes: a tubular housing; an LED light-emitting unit coupled to the tubular housing; a sleeve unit coupled movably to the tubular housing; and a positive lens mounted in the sleeve unit and spaced apart from and aligned with the LED light-emitting unit along an axis of the tubular housing. The sleeve unit is movable relative to the tubular housing and the LED light-emitting unit along the axis of the tubular housing so as to adjust a distance between the positive lens and the LED light-emitting unit.

Abstract: A battery receptacle includes an insulative casing having top and bottom walls for accommodating a battery unit therebetween. A pair of first anode and cathode terminals are disposed on the top wall. An electrical contact and a pair of second anode and cathode terminals are disposed on the bottom wall. A positive-electrode connecting member interconnects electrically the first and second anode terminals, and is adapted to be in electrical contact with a positive electrode of the battery unit. The electrical contact is adapted to be in electrical contact with a negative electrode of the battery unit. A negative-electrode connecting member is connected electrically to the first and second cathode terminals and the electrical contact.

Abstract: A light emitting diode (LED) lamp includes a housing, and a heat conducting member made of a highly thermally conductive material. The heat conducting member includes a base plate that is mounted on the housing and that has one side opposite to the housing, and at least one heat conducting fin extending from the base plate away from the housing. The LED lamp further includes a light emitting diode unit mounted on the side of the base plate.

Abstract: A flashlight includes a battery housing, a lamp seat, a lamp unit, a heat-conductive casing, and a heat-dissipating plate. The lamp seat is mounted on one end of the battery housing. The lamp unit includes a substrate having a first side provided with a metal layer, and an LED lamp mounted on a second side of the substrate opposite to the metal layer. The heat-conductive casing is attached to the battery housing, and is disposed around the lamp seat and the lamp unit. The heat-dissipating plate is sandwiched between the lamp seat and the metal layer of the substrate, and is in contact with the heat-conductive casing. Heat generated by the lamp unit is dissipated via the metal layer, the heat-dissipating plate, and the heat-conductive casing.

Abstract: A focus-adjustable LED flashlight includes: a tubular housing; an LED light-emitting unit coupled to the tubular housing; a sleeve unit coupled movably to the tubular housing; and a positive lens mounted in the sleeve unit and spaced apart from and aligned with the LED light-emitting unit along an axis of the tubular housing. The sleeve unit is movable relative to the tubular housing and the LED light-emitting unit along the axis of the tubular housing so as to adjust a distance between the positive lens and the LED light-emitting unit.

Abstract: A switch device of a flashlight includes a tubular switch housing disposed in a barrel, abutting against a coupling ring mounted fixedly in the barrel, and having an outer circumferential surface formed with an engaging groove corresponding to a positioning groove in the inner surface of the barrel. The engaging groove has a depth that gradually increases toward an open end of the barrel. A switch unit is housed in the switch housing, and includes an operating member extending outwardly of the barrel through an opening in the switch housing and a through hole in the barrel. A wedge member engages the positioning groove in the barrel and the engaging groove in the switch housing, and has a thickness that gradually increases toward the open end of the barrel so as to prevent movement of the switch housing in the barrel.

Abstract: A flashlight includes a battery housing, a lamp seat, a lamp unit, a heat-conductive casing, and a heat-dissipating plate. The lamp seat is mounted on one end of the battery housing. The lamp unit includes a substrate having a first side provided with a metal layer, and an LED lamp mounted on a second side of the substrate opposite to the metal layer. The heat-conductive casing is attached to the battery housing, and is disposed around the lamp seat and the lamp unit. The heat-dissipating plate is sandwiched between the lamp seat and the metal layer of the substrate, and is in contact with the heat-conductive casing. Heat generated by the lamp unit is dissipated via the metal layer, the heat-dissipating plate, and the heat-conductive casing.

Abstract: A switch device of a flashlight includes a tubular switch housing disposed in a barrel, abutting against a coupling ring mounted fixedly in the barrel, and having an outer circumferential surface formed with an engaging groove corresponding to a positioning groove in the inner surface of the barrel. The engaging groove has a depth that gradually increases toward an open end of the barrel. A switch unit is housed in the switch housing, and includes an operating member extending outwardly of the barrel through an opening in the switch housing and a through hole in the barrel. A wedge member engages the positioning groove in the barrel and the engaging groove in the switch housing, and has a thickness that gradually increases toward the open end of the barrel so as to prevent movement of the switch housing in the barrel.

Abstract: A battery receptacle includes an insulative casing, positive and negative electrodes, and an interface assembly. The positive and negative electrodes have end portions disposed on the casing. The negative electrode has an end portion disposed on the casing. The interface assembly is disposed on the casing, and includes an insulative body, anode and cathode terminals, a contact element, and an insulating protrusion. The anode terminal projects from the insulative body, and is in electrical contact with the end portion of the positive electrode. The cathode terminal is provided on a periphery of the insulative body. The contact element is in electrical contact with the cathode terminal, projects from the insulative body, and is in electrical contact with the end portion of the negative electrode. The insulating protrusion is provided on the insulative. body, and abuts against the end portion of the positive electrode.

Abstract: A flashlight includes a tubular housing, a module-receiving housing, an end closure, and a light emitting module. The tubular housing has opposite first and second ends. The module-receiving housing is connected to the first end of the tubular housing. The end closure is connected to the second end of the tubular housing, and is provided with a conductive urging member that extends into the tubular housing. The light emitting module is mounted in the module-receiving housing, and includes a heat dissipating member, a reflector, and a light emitting member. The heat dissipating member is in contact with the tubular housing so as to dissipate heat resulting from the light emitting member through the tubular housing.

Abstract: A flashlight includes a conductive casing, a lamp seat holder, a reflector, a dielectric body, and a lamp seat. The lamp seat holder defines a receiving space, and has an inner end inserted into one end of the casing and an outer end extending outwardly from the casing. The reflector has one end inserted threadedly into the outer end of the lamp seat holder. The dielectric body is fitted in the inner end of the lamp seat holder, and holds a pair of electrode elements. The lamp seat is disposed within the lamp seat holder between the dielectric body and the reflector.

Abstract: A flashlight includes a conductive barrel, a lamp unit, a connecting device and a tail cap unit. The connecting device includes a conductive ring, an insulator seat, a conductive biasing member and a positioning cap. The biasing member is disposed in a retaining hole in the insulator seat, and is prevented from removal from the retaining hole by the positioning cap.

Abstract: A flashlight includes a conductive barrel, a lamp unit, a connecting device and a tail cap unit. The connecting device includes a conductive ring, an insulator seat, a conductive biasing member and a positioning cap. The biasing member is disposed in a retaining hole in the insulator seat, and is prevented from removal from the retaining hole by the positioning cap.

Abstract: A flashlight includes a conductive barrel, a lamp unit and a tail cap switch. The tail cap switch includes a tail cap member, a push button member movable relative to the tail cap member, a conductive biasing member, and a contact blocking member to control the moving range of the push button member. In practice, the tail cap member is adjustable relative to the barrel to one of a normally closed position, a normally open position, and a switch on/off position between the normally closed position and the normally open position.