Abstract: A positioning structure of a clamper of a threading machine for a racket contains: a rack, an engagement protrusion, an operation member, and two springs. A fixing holder is erected on a support plate of the threading machine, and the rack includes multiple first teeth, the fixing holder includes an accommodation chamber with an opening. The engagement protrusion is received in the accommodation chamber and includes a toothed extension on which multiple second teeth are formed. The engagement protrusion further includes a recess and an abutting fence. The operation member includes a drive portion and a push portion. The two springs are mounted on a top of the engagement protrusion, and two ends of each spring abut against the engagement protrusion and the fixing holder respectively so that each spring forces the engagement protrusion to engage with the rack.

Abstract: A positioning structure of a clamper of a threading machine for a racket contains: a rack, an engagement protrusion, an operation member, and two springs. A fixing holder is erected on a support plate of the threading machine, and the rack includes multiple first teeth, the fixing holder includes an accommodation chamber with an opening. The engagement protrusion is received in the accommodation chamber and includes a toothed extension on which multiple second teeth are formed. The engagement protrusion further includes a recess and an abutting fence. The operation member includes a drive portion and a push portion. The two springs are mounted on a top of the engagement protrusion, and two ends of each spring abut against the engagement protrusion and the fixing holder respectively so that each spring forces the engagement protrusion to engage with the rack.

Abstract: A string clamping device of a threading machine for a racket contains: a clamp unit, a tightening unit, an adjustment disc, a connection column, and a fixing structure. The clamp unit includes a body, a locking seat, and two first springs. The body has multiple first paws, the locking seat has multiple second paws, and among the multiple first and second paws is defined a gap of the clamp unit. The tightening unit includes an abutting block and an operation handle, the body has a first protrusion with a first through orifice, and the adjustment disc includes multiple teeth, wherein between any two adjacent teeth is defined a recess. The fixing structure includes an affix member, a coupling shaft, a second spring, a screwing element, and a support part, wherein the affix member has a retaining portion, and the second spring contacts with a drive tab of the support part.

Abstract: A voltage adjustment system includes an adjust module, a control module, and a load module. The adjust module includes a voltage converting unit which includes a buck converter and an inductor. The control module includes a first resistor, a second resistor, and a variable resistance unit. The load module is electrically connected to the buck converter via the inductor. A connecting point between the inductor and the load module is grounded via the first resistor and the second resistor in series. A connecting point between the first resistor and the second resistor is grounded via the variable resistance unit. The variable resistance unit includes a thermal resistor located adjacent to the inductor. A resistance of the thermal resistor changes when a temperature of the inductor changes. An equivalent resistance of the variable resistance unit changes to adjust a voltage received by the load module.

Abstract: An over-current regulating system includes a protecting resistor, an amplifying circuit, and a comparing circuit. The protecting resistor is configured to be electrically coupled to a power supply unit. The amplifying circuit is electrically coupled to the protecting resistor and the comparing circuit and configured to amplify a voltage of the protecting resistor, and output the amplified voltage value to the comparing circuit. The comparing circuit is configured to determine whether the amplified voltage is greater than a first predetermined value when the comparing circuit is coupled to the power supply unit. When the voltage is greater than the first predetermined value, the comparing circuit outputs a controlling signal to reduce a work frequency of a load.

Abstract: An optical lens module includes a barrel holder, an optical lens barrel, a first thread, a second thread and a plurality of engaging protrusions. The first thread is formed on one of the barrel holder and the optical lens barrel. The second thread is formed on the other one of the barrel holder and the optical lens barrel. The engaging protrusions extend from the root of the first thread for contact with the crest of the second thread. Each of the engaging protrusions has an end surface disposed between the crest and the root of the first thread. A clearance is formed between the crest of the first thread and the root of the second thread and between the root of the first thread and the crest of the second thread.

Abstract: A system for charging and discharging batteries includes a battery module, an adapter, a charger, and an electronic device electrically connected to the charger and the battery module. The battery module includes a first cell battery, a second cell battery, and a first switch electrically connected to the first and second battery cells. The adapter receives an AC voltage, and converts the AC voltage to a DC voltage. The charger receives the DC voltage, and charges the battery module accordingly. The electronic device is electrically connected to the charger and the battery module. When the charger charges the battery module, the first switch is switched to electrically connect the first and second battery cells with the charger in series. When the battery module discharges to the electronic device, the first switch is switched to electrically connect the first and second battery cells with the electronic device in parallel.

Abstract: A voltage adjustment system includes an adjust module, a control module, and a load module. The adjust module includes a voltage converting unit which includes a buck converter and an inductor. The control module includes a first resistor, a second resistor, and a variable resistance unit. The load module is electrically connected to the buck converter via the inductor. A connecting point between the inductor and the load module is grounded via the first resistor and the second resistor in series. A connecting point between the first resistor and the second resistor is grounded via the variable resistance unit. The variable resistance unit includes a thermal resistor located adjacent to the inductor. A resistance of the thermal resistor changes when a temperature of the inductor changes. An equivalent resistance of the variable resistance unit changes to adjust a voltage received by the load module.

Abstract: An over-current regulating system includes a protecting resistor, an amplifying circuit, and a comparing circuit. The protecting resistor is configured to be electrically coupled to a power supply unit. The amplifying circuit is electrically coupled to the protecting resistor and the comparing circuit and configured to amplify a voltage of the protecting resistor, and output the amplified voltage value to the comparing circuit. The comparing circuit is configured to determine whether the amplified voltage is greater than a first predetermined value when the comparing circuit is coupled to the power supply unit. When the voltage is greater than the first predetermined value, the comparing circuit outputs a controlling signal to reduce a work frequency of a load.

Abstract: A lens barrel includes a barrel wall disposed about a longitudinal axis, an external thread continuously formed on the barrel wall and having a continuous crest, and two parting lines that are longitudinally formed on the external thread and that are symmetrical about the longitudinal axis. A projection of the crest of the external thread on a plane orthogonal to the longitudinal axis has a maximum diameter and a minimum diameter. A difference between the maximum and minimum diameters is between 0.04 mm and 0.18 mm. Each of the two parting lines is disposed on portions of the external thread that define the minimum diameter.

Abstract: A keyboard includes a key portion, an inputting detecting module, and a lighting controlling module. The key portion includes a plurality of key caps aligned in a regular fashion. Each of the plurality of key caps includes a letter identifier and a first assistant identifier and a second assistant identifier printed thereon. The inputting detecting module detects a current input of a letter of the alphabet, a first assistant identifier, or a second assistant identifier, of the keyboard. The lighting controlling module is connected to the inputting detecting module. The lighting controlling module lights the particular identifier, either letter, or first assistant identifier, or second assistant identifier, on the key cap when the inputting detecting module detects such an input by the keyboard.

Abstract: A power supply circuit is configured to supply a working voltage for an electric load. The power supply circuit includes a controller and a power supply module connected to the controller. The power supply module includes a first output channel and a second output channel both of which are connected to the electric load. A current sensor is connected to the controller and configured to sense a current output from the first output channel. Either the first output channel or the second output channel is deactivated by the controller when the current sensed by the current sensor is less than a predetermined current value. Both of the first output channel and the second output channel are activated when the current sensed by the current sensor is greater than the predetermined current value.

Abstract: A charging and discharging system for a battery includes an adapter, a charging controller, a converting module, and a battery. The adapter receives an AC voltage, converts the AC voltage to a DC voltage, and electrically connects the charging controller to the converting module. When the adapter is supplying power, the charging controller can switch on and switch off the converting module, and the converting module accordingly connects and disconnects the adapter to or from the battery. When the adapter is not supplying power, the battery provides power for the electronic device. Therefore, the battery is electrically isolated from the adapter and can be protected from a sudden power surge when the adapter is powered on.

Abstract: A power supply detection circuit includes a controller including a power module for supplying an input voltage to a to-be-tested power supply unit, a controlling module, a signal module, and a detection module, a resistor, and a MOSFET. A first end of the resistor connects an output end of the power supply unit. A second end of the resistor connects to the MOSFET. The MOSFET connects to the signal module. The detection module connects the output end. The control module controls the signal module to generate a pulse signals. The MOSFET is turned on to connect the resistor to the power supply unit to generate a fast-rising current when the pulse signal is in a high level. The detection module detects an output voltage of the output end, to confirm whether the output voltage is equal to the input voltage. This patent further discloses a power supply detection method.

Abstract: An optical touch-control includes: four light-guide modules cooperating to define a touch-control zone, each of the light-guide modules including a light-guide strip that has a light-entry surface oriented toward a respective one of first and second ones of corners defined by the light-guide modules, and a light-exit surface that is oriented toward the touch-control zone; two light-emitting modules disposed in the first one of the corners and two light-emitting modules disposed in the second one of the corners, each of the light-emitting modules being oriented toward the light-entry surface of a corresponding one of the light-guide modules, light that enters each of the light-guide modules via the light-entry surface thereof exiting from the light-guide module via the light-exit surface thereof; and three image acquisition modules disposed respectively in the first and second ones of the corners and a remaining one of the corners, and oriented toward the touch-control zone.

Abstract: A lens barrel includes a barrel wall disposed about a longitudinal axis, an external thread continuously formed on the barrel wall and having a continuous crest, and two parting lines that are longitudinally formed on the external thread and that are symmetrical about the longitudinal axis. A projection of the crest of the external thread on a plane orthogonal to the longitudinal axis has a maximum diameter and a minimum diameter. A difference between the maximum and minimum diameters is between 0.04 mm and 0.18 mm. Each of the two parting lines is disposed on portions of the external thread that define the minimum diameter.

Abstract: A system for charging and discharging batteries includes a battery module, an adapter, a charger, and an electronic device electrically connected to the charger and the battery module. The battery module includes a first cell battery, a second cell battery, and a first switch electrically connected to the first and second battery cells. The adapter receives an AC voltage, and converts the AC voltage to a DC voltage. The charger receives the DC voltage, and charges the battery module accordingly. The electronic device is electrically connected to the charger and the battery module. When the charger charges the battery module, the first switch is switched to electrically connect the first and second battery cells with the charger in series. When the battery module discharges to the electronic device, the first switch is switched to electrically connect the first and second battery cells with the electronic device in parallel.

Abstract: An exemplary power supply system for feeding electric power to an electronic device is provided. The power supply system includes an internal battery installed inside the electronic device and an external battery connected to the internal battery through a first switch. When the internal battery is above a set energy level, the first switch is turned off and the internal battery outputs electric power to the electronic device. When the internal battery falls below the first set energy level, the first switch is turned on and the external battery outputs electric power to the electronic device. A power supply method based upon the power supply system is also provided.

Abstract: This invention relates to a mobile electronic device and a power management method of a battery module thereof. The mobile electronic device includes a battery module, a charging/discharging module, and a control module. The charging/discharging module is coupled with the battery module. The control module is coupled with the battery module and the charging/discharging module. When the power supply is coupled with the mobile electronic device and the system time is not within a maintenance period, the control module controls the charging/discharging module to maintain capacity of the battery module within a first capacity range. When the power supply is coupled with the mobile electronic device and the system time is within the maintenance period, the control module controls the charging/discharging module to maintain the capacity of the battery module within a second capacity range.

Abstract: A positioning device for holding member of a sport racket stringing machine includes a rack which is engaged with the top board of the stringing machine and has multiple one-way ratchet teeth. The holding member has a chamber and a contact member is movably located in the chamber and inclinedly engaged with the ratchet teeth of the rack to position the holding member. A spring is connected between the body and the contact member to urge the contact member to contact the rack. The operation member is pivotably connected to the chamber. The operation member has a driving portion and a positioning portion with a curved operation portion connected therebetween. The operation portion is pivotably connected to the body. The top end of the contact member extends between the driving portion and the positioning portion and the driving portion pivots the contact member to move the holding member.