摘要:
A key switch used for a keyboard incorporated as an input device in electronic equipment. The key switch includes a support plate; a key top arranged above the support plate; a pair of link members interlocked to each other to support the key top above the support plate and direct the key top in a vertical direction; and a switch mechanism capable of opening and closing a contact section of an electric circuit in accordance with a vertical movement of the key top. The switch mechanism includes a membrane switch sheet carrying the contact section at a position corresponding to the key top and placed on the support plate. Each of the link members includes a sliding part slidably engaged with the support plate. The membrane switch sheet is provided with a through-hole in a region where the sliding part of each link member is engaged with the support plate, the sliding part of the link member being slidably placed on the support plate through the through-hole in the membrane switch sheet.
摘要:
A pointing device including: a base part; an operating part shiftably supported on the base part; a magnet carried on the operating part; magneto-electro transducers carried on the base part at a location close to the magnet; and a switch mechanism arranged between the base part and the operating part. The operating part includes a first member carrying the magnet and a second member connected to the first member in a mutually shiftable manner. The first member is provided with a rocking center and is rockably supported on the base part, so as to cause a relative displacement between the magnet and the magneto-electro transducers. The second member is capable of rocking together with the first member about the rocking center and of shifting relative to the first member in a motion different from a rocking motion, so as to actuate the switch mechanism.
摘要:
A gear-link type key switch including a pair of link members on a base panel, wherein the key switch has a constitution in that the pair of link members are not disengaged when a key top is attached to the link members. Furthermore, the key switch alleviates the need for an undesired attaching method because of its structure, when a key top is attached to the link members. In order to prevent the pair of link members from disengaging in an anteroposterior direction, wall members are provided on the base panel of the key switch. The wall members arranged on opposite sides of a contact section of the link members, abutting the outside of pivoting shafts, are made by cutting the plate member of the base panel and pulling up the cut plate member, and are an integral part of the plate member.
摘要:
A keyboard having: a base panel, a switch panel including a hole portion, a membrane sheet including a contact portion, a key top adapted to be depressed for switching the contact portion ON, and a housing supporting and guiding the key top to move freely in a vertical direction, including each a tube portion on an upper end side having a guide hole formed for inserting a stem formed integrally with the key top and a flange portion on an lower end side extending laterally around the tube portion in a size larger than the hole portion; wherein the housing is inserted into the hole portion from a back side of the switch panel, the flange portion being attached to the back side of the switch panel.
摘要:
A key switch unit includes a keycap elongated in a lengthwise direction; a switch mechanism; a supporting plate supporting the switch mechanism; and a key reinforcement mechanism engaging the keycap on its lower side for reinforcement. The key reinforcement mechanism includes a first wire member having a beam part extending over substantially an overall dimension of the keycap in the lengthwise direction; a second wire member having a beam part extending in the lengthwise direction between a region contacting the switch mechanism and a first lengthwise end of the keycap; and a third wire member having a beam part extending in the lengthwise direction between the region and a second lengthwise end of the keycap. The beam parts engage the keycap on its lower side. The first, second, and third wire members have respective end parts turnably supported on the supporting plate.
摘要:
A gear-link type key switch including a pair of link members on a base panel, wherein the key switch has a constitution in that the pair of link members are not disengaged when a key top is attached to the link members. Furthermore, the key switch alleviates the need for an undesired attaching method because of its structure, when a key top is attached to the link members. In order to prevent the pair of link members from disengaging in an anteroposterior direction, wall members are provided on the base panel of the key switch. The wall members arranged on opposite sides of a contact section of the link members, abutting the outside of pivoting shafts, are made by cutting the plate member of the base panel and pulling up the cut plate member, and are an integral part of the plate member. With this arrangement, it is impossible to carry out a key top attaching method which is undesirable from the structural view point and in which first, a first pair of pivot support sections provided on one side of the key top are engaged by the corresponding pivoting shafts provided on one side of the pair of link members, and then a second pair of pivot support sections provided on the other side of the key top are engaged by the corresponding pivoting shafts provided on the other side of the pair of link members.
摘要:
A carrier detection circuit of the present invention detects groups of pulses having a carrier frequency by using a detector, and integrates, by an integrator, a time in which the groups are detected, so as to generate a carrier detection level. Therefore, a transistor is only requested to have responsibility with respect to a frequency of a base band component, but not to the carrier frequency. This ensures a margin with respect to a response of the transistor, while allowing a feeble current to be used as charging and discharging currents for the capacitor. In this way, even if a capacitor in use has such a small capacity that the capacitor can be incorporated in an integrated circuit, the detection of the carrier is performed accurately. Meanwhile, by further providing a level change-over circuit, which increases an output of the detector relative to a reference integral value during a time in which the carrier is detected, it is possible to reduce malfunction caused by a light noise having swelling, in case an infrared ray remote control is used.
摘要:
In an optical communication-use receiving circuit of the present invention, the pulse width of the received pulse which is a binary signal corresponding to the signal optical pulse is specified by using an integration circuit and a trigger generating circuit. If the pulse width of the received pulse is not shorter than a predetermined value, a signal having a fixed pulse width is outputted as an output signal from a one-shot pulse generating circuit, so that a pulse having a constant pulse width corresponding to the specified communication speed is outputted. Accordingly, if the pulse width deriving from the signal optical pulse is larger than a certain value, the communication is deemed as a low-speed communication, and a pulse having a constant pulse width corresponding to the communication speed is outputted. As a result, it is possible to realize a small-size receiving circuit and a small-size electronic device which require no external switching-over terminal.
摘要:
A charge/discharge circuit creates a carrier detection level based on a received signal in a carrier detector circuit for detecting the presence or absence of a carrier in such applications as a receiver for an IR remote controller. The charge/discharge circuit operates to amplify a current, that is produced in n-type transistors QN1, QN2, QN3 and a reference current source, in a p-type transistor QP1. The amplified current is mirrored by a current mirror circuit to be supplied as an emitter current of a p-type transistor QP2. The charge/discharge circuit charges a capacitor with a small current, i.e., a base current of the p-type transistor QP2. The charge/discharge circuit includes a bias voltage source which produces such a bias voltage that the emitter-collector voltage of the p-type transistor QP1 becomes substantially equal to the emitter-collector voltage of the p-type transistor QP2. As a result, it is possible to limit an error of a charge current charged into the capacitor, which is caused by the emitter-collector voltage dependent change of the collector current and thus the base current, known as the Early effect.
摘要:
A keyboard having a backlight function, the keyboard includes a key top having a light permeating region, the key top being where one end of a link member is provided; a membrane sheet having a contact, the contact being conductive when the key top is pushed; a support panel made of metal, the support panel being where another end of the link member is provided; and a light guide plate where a light is guided from a light source. The key top, the membrane sheet, the support panel, and the light guide plate are stacked from a top side; the light guide plate is formed of a member having an elasticity higher than an elasticity of the support panel; and a part of an external edge part of the light guide plate, seen from the top side, projects outside the support panel.