Abstract: A hydraulic control apparatus for an automatic transmission, including a sequential shift control means for performing sequential shift control in a case where it is necessary to execute the second shift during execution of the first shift. The sequential shift control includes starting reduction of hydraulic fluid pressure in the third friction element when a parameter that varies in accordance with a degree of progress of the first shift has reached a predetermined value, and performing piston stroke control that includes outputting a high hydraulic pressure command as a hydraulic fluid pressure to the second friction element when the selector valve is switched from the second position to the first position, and subsequent to completion of outputting of the high hydraulic pressure command, outputting a low hydraulic pressure command that is lower than the high hydraulic pressure command.

Abstract: To provide a functional spectral filter through which, it is possible for an observer wearing the functional spectral filter to change his or her color sensitivity (ease of color distinction), and which is for designing a color scheme easy to be distinguished for a color deficient observer by using the filter. A functional spectral filter including a multilayer is formed in accordance with a thin film design (an optimization method) determined by use of a color vision theory so as to make color sensitivity into a desired pattern. With respect to combinations that two colors among a plurality of specified colors are combined, color differences in the respective combinations are made close to a color difference given in advance. Alternatively, with respect to specified combinations, the color differences are made small or the color differences are made large.

Abstract: To provide a functional spectral filter through which, it is possible for an observer wearing the functional spectral filter to change his or her color sensitivity (ease of color distinction), and which is for designing a color scheme easy to be distinguished for a color deficient observer by using the filter. A functional spectral filter including a multilayer is formed in accordance with a thin film design (an optimization method) determined by use of a color vision theory so as to make color sensitivity into a desired pattern. With respect to combinations that two colors among a plurality of specified colors are combined, color differences in the respective combinations are made close to a color difference given in advance. Alternatively, with respect to specified combinations, the color differences are made small or the color differences are made large.

Abstract: A hydraulic control apparatus for an automatic transmission, including a sequential shift control means for performing sequential shift control in a case where it is necessary to execute the second shift during execution of the first shift. The sequential shift control includes starting reduction of hydraulic fluid pressure in the third friction element when a parameter that varies in accordance with a degree of progress of the first shift has reached a predetermined value, and performing piston stroke control that includes outputting a high hydraulic pressure command as a hydraulic fluid pressure to the second friction element when the selector valve is switched from the second position to the first position, and subsequent to completion of outputting of the high hydraulic pressure command, outputting a low hydraulic pressure command that is lower than the high hydraulic pressure command.

Abstract: An automatic transmission has an electronic control unit and a hydraulic control unit. The electronic control unit outputs an engagement command pressure to a solenoid disposed in a hydraulic control unit to generate a shelf pressure to upshift the automatic transmission. The engagement command pressure is corrected downwardly when the maximum rate of the gear ratio change is larger than the rate of change of a thrust-up determination gear ratio, and upwardly when the maximum rate of the gear ratio change is smaller than the rate change of a prolongation determination gear ratio. By correcting the engagement command pressure using the maximum rate of the gear ratio change, a proper output shaft torque wave form can be obtained so that a fluctuation of an output shaft torque during a torque phase while upshifting has no strong influence on the acceleration of a vehicle to achieve a comfortable shift feeling.

Abstract: In a shift control apparatus for an automatic transmission, there is provided a target speed change permitting means which; at the time of a dual changeover shift which is a shift from an Nth speed achieved by bringing a first friction element and a second friction element to an engagement state, to an (N-?)th speed achieved by engaging a third friction element and a fourth friction element, and which has at least one intermediate speed, between the Nth speed and the (N-?)th speed, achieved by engaging the second friction element and the third friction element; checks a driver's shift intention again at the time of attainment of the gear ratio corresponding to the intermediate speed, and permits the target speed to be changed to the speed according to the driver's intention when the target speed is different from the (N-?)th speed.

Abstract: A system for controlling a torque reduction at shifting for an automatic transmission is provided with actual gear-ratio detecting means for detecting an actual gear ratio out of input rotation and output rotation of the automatic transmission, and torque-reduction amount computing means for calculating a torque-reduction amount out of a torque-reduction set gain set previously, which is a rate of change of the torque-reduction amount with respect to a change in gear ratio, and the detected actual gear ratio. With this, the start and completion timings of torque-reduction control can be optimized to prevent elongation of shifting. This results in enhancement in the shift quality and in the endurance reliability of a friction material for shifting.

Abstract: An automatic transmission comprises an electronic control unit and a hydraulic control unit. The electronic control unit commands an engagement command pressure to a solenoid disposed in a hydraulic control unit until the time engagement element pressure generated by the solenoid reaches to a shelf pressure, thereby an upshift of the automatic transmission is achieved. The engagement command pressure is corrected in a decrease direction when a maximum rate of change of a gear ratio is larger than a rate of change of a thrust-up determination gear ratio, and the engagement command pressure is corrected in a rise direction when the maximum rate of change of the gear ratio is smaller than a rate of change of a prolongation determination gear ratio. Thus, by correcting an engagement command pressure using the maximum rate of change of the gear ratio, a proper output shaft torque wave form can be obtained.

Abstract: In a shift control system for an automatic transmission, shelf-pressure control means include means for increasing the engagement pressure of the friction elements at a first gradient as previously set after output of the shift command, wherein after output of the shift command and when start of the inertia phase is detected, a torque-reduction command is output to the torque-reduction control means, the engagement pressure at detection of the inertia phase is set as an initial shelf pressure to increase the shelf pressure at a second gradient set for each speed, and a torque variation part oil pressure is added only when detecting a variation in throttle opening, and wherein after start of the inertia phase and when completion of the inertia phase is detected, a torque-reduction completion command is output to the torque-reduction control means.

Abstract: There is provided a hydraulic control device for an automatic transmission, which is comprised of an engagement state determining section and a protection control section. If the engagement state determining section determines that each clutch, which is supplied with a line pressure via a regulating valve having a spool and has an oil pressure switch disposed in an oil channel, is held in an engaged state when gears are not changed, the protection control section sets a command pressure for the regulating valve to a protective oil pressure lower than the line pressure. This brings the regulating valve into a pressure-regulating state to cause lands of the spool to form apertures that reduce hydraulic vibration applied to the line pressure. This inhibits an oil pressure beyond an acceptable value from being applied to the oil pressure switch, and therefore improves the durability of the oil pressure switch.

Abstract: In a shift control system for an automatic transmission, shelf-pressure control means include means for increasing the engagement pressure of the friction elements at a first gradient as previously set after output of the shift command, wherein after output of the shift command and when start of the inertia phase is detected, a torque-reduction command is output to the torque-reduction control means, the engagement pressure at detection of the inertia phase is set as an initial shelf pressure to increase the shelf pressure at a second gradient set for each speed, and a torque variation part oil pressure is added only when detecting a variation in throttle opening, and wherein after start of the inertia phase and when completion of the inertia phase is detected, a torque-reduction completion command is output to the torque-reduction control means.

Abstract: In a shift control apparatus for an automatic transmission, there is provided a target speed change permitting means which; at the time of a dual changeover shift which is a shift from an Nth speed achieved by bringing a first friction element and a second friction element to an engagement state, to an (N−&agr;)th speed achieved by engaging a third friction element and a fourth friction element, and which has at least one intermediate speed, between the Nth speed and the (N−&agr;)th speed, achieved by engaging the second friction element and the third friction element; checks a driver's shift intention again at the time of attainment of the gear ratio corresponding to the intermediate speed, and permits the target speed to be changed to the speed according to the driver's intention when the target speed is different from the (N−&agr;)th speed.

Abstract: A system for controlling a torque reduction at shifting for an automatic transmission is provided with actual gear-ratio detecting means for detecting an actual gear ratio out of input rotation and output rotation of the automatic transmission, and torque-reduction amount computing means for calculating a torque-reduction amount out of a torque-reduction set gain set previously, which is a rate of change of the torque-reduction amount with respect to a change in gear ratio, and the detected actual gear ratio. With this, the start and completion timings of torque-reduction control can be optimized to prevent elongation of shifting. This results in enhancement in the shift quality and in the endurance reliability of a friction material for shifting.

Abstract: There is provided a hydraulic control device for an automatic transmission, which is comprised of an engagement state determining section and a protection control section. If the engagement state determining section determines that each clutch, which is supplied with a line pressure via a regulating valve having a spool and has an oil pressure switch disposed in an oil channel, is held in an engaged state when gears are not changed, the protection control section sets a command pressure for the regulating valve to a protective oil pressure lower than the line pressure. This brings the regulating valve into a pressure-regulating state to cause lands of the spool to form apertures that reduce hydraulic vibration applied to the line pressure. This inhibits an oil pressure beyond an acceptable value from being applied to the oil pressure switch, and therefore improves the durability of the oil pressure switch.

Abstract: The first and second weld areas of respective first and second metallic workpieces of aluminum or aluminum alloy are held in abutment against each other with a surface of the second metallic workpiece being positioned on a positioning guide of the first metallic workpiece. A recess is defined between the positioning guide and the second metallic workpiece. A high-density energy beam such as a laser beam is applied to the first and second weld areas thereby to develop a molten pool therein that grows toward the positioning guide until metallic oxide films formed on the first and second metallic workpieces are forced into the recess by the molten pool. As no metallic oxide films are present in a weld joint between the first and second metallic workpieces, the resultant welded structure is of a high mechanical strength.