摘要:
A power steering apparatus having a hydraulic pump for outputting a pressurized fluid, an assist force generation mechanism hydraulically connected to the pump through a supply passage to generate an assist force in response to rotation of a steering wheel, wherein the assist force generation mechanism has a characteristic that the back pressure thereof increases when the steering wheel is rotated. The power steering apparatus further comprises a flow control valve having a spool which is moved in response to a pressure drop at a metering orifice disposed in the middle of the supply passage, so as to control the flow rate of the pressurized fluid to be constant. The spring chamber of the flow control valve is connected to a reservoir through a drain passage, and a drain valve is disposed in the drain passage for allowing the flow of pressurized fluid from the spring chamber to the reservoir when the back pressure of the assist force generation mechanism is low, and for prohibiting the flow of the pressurized fluid when the back pressure of the assist force generation mechanism increases.
摘要:
A power steering apparatus having a fluid source for discharging pressurized fluid, a power cylinder, a control valve responsive to operation of a steering wheel for supplying the power cylinder with pressurized fluid from the fluid source, and a reservoir. The control valve has a first control portion for controlling the flow of pressurized fluid from the fluid source to the reservoir, and a second control portion for controlling the flow of pressurized fluid to the power cylinder. The first control portion has two paths connecting the fluid source and the reservoir, each of the paths being formed with at least one variable orifice of a center-open type which opens when the control valve is in a neutral state. The second control portion has two supply paths communicating with the fluid source and a pair of chambers of the power cylinder, each of the supply paths being formed with a variable orifice of a center-close type which closes when the control valve is in the neutral state, and two drain paths communicating with the pair of chambers and the reservoir, each of the drain paths being formed with a variable orifice of a center-open type which opens when the control valve is in the neutral state.
摘要:
A power steering apparatus is composed a fluid source for discharging pressurized fluid, a power cylinder, a control valve responsive to operation of a steering wheel for supplying the power cylinder with pressurized fluid from the fluid source, and a reservoir. The control valve has a first control portion for controlling the flow of pressurized fluid from the fluid source to the reservoir, and a second control portion for controlling the flow of pressurized fluid to the power cylinder. The first control portion has four paths communicating with the fluid source and the reservoir, and each of the four paths is formed with a center-open variable orifice which opens when the control valve is in a neutral state. The second control portion has two supply paths communicating with the fluid source and a pair of chambers of the power cylinder, each of the two supply paths is formed with a semi-center-open variable orifice which opens when the control valve is in the neutral state, and two drain paths communicating with the chambers of the power cylinder and the reservoir, each of the two drain paths is formed with a center-closed variable orifice of which closes when the control valve is in the neutral state.
摘要:
A power steering apparatus comprises a fluid source for supplying pressurized fluid, a power cylinder having a pair of fluid chambers, a control valve, and a drain control mechanism. The control valve is composed of first and second control portions. The first control portion has four paths connecting the fluid source and the reservoir, and each of the four paths is formed with a variable orifice of center-open type. The second control portion has two supply paths communicating the fluid source with the fluid chambers of the power cylinder, each of the supply paths being formed with a variable orifice of center-open type, and two drain paths communicating the fluid chambers with the reservoir, each of the drain paths being formed with a variable orifice of center-closed type. The drain control mechanism is responsive to differential pressure between the fluid chambers of the power cylinder to control the communication of one fluid chamber under high pressure with the reservoir, and is responsive to a vehicle speed to control the communication of both fluid chambers with the reservoir.
摘要:
In a power steering apparatus having a control valve with a first control valve portion and a second control valve portion to enhance rigidity of a steering operation, an amount of an overlapping portion of an overlap variable orifice is designed larger than an amount of an unlapping portion of an untapped variable orifice in the control valve because of dispersion during manufacture. When the overlap variable orifice finishes overlapping, the unlapped variable orifice has already started unlapping. Therefore, since the overlap variable orifice and the unlapped variable orifice never become unlapping form simultaneously regardless of the dispersion, the control valve is capable of minimizing a difference of the flow between a plurality of the second control valve portion. As a result, the power steering apparatus relative to the invention prevents enlargement of noise caused by an unbalance of the flow between a plurality of the second control valve portions in the control valve.
摘要:
In a power steering apparatus comprising a pump, a reservior, a power cylinder having two opposite chambers, and a rotary control vale, the rotary control valve consists of a first control portion which communicates between the pump and the reservior, and a second control portion which communicates not only between the pump and the reservior but also with the power cylinder. In the first control portion, each of four underlapping variable orifices is so provided as to take the form of underlap in itself. In the second control portion, two underlapping variable orifices are provided on the side of the pump, and besides each of two overlapping variable orifices is so provided as to take the form of overlap in itself on the side of the reservior. In this manner, while a steering wheel is operated within a predetermined angle, an opening area of the overlapping variable orifice changes little. When the steering wheel is operated beyond the predetermined valve, the opening are increases sufficiently according to steering operation. As a result, a differential pressure between the chambers is prevented from originating at and around the neutral position of the steering wheel. Consequently, as for steering feeling, the rigidity of the steering operation at and around the neutral position is enhanced, and furthermore, a beginning point where the power assist is produced by operating the steering wheel from its neutral position is distinguished.
摘要:
A method for attaching a wire-identifying tab to an electric wire end, the tab comprising a marking portion having identification mark and being a cylinder having a slit extending axially over the full length of the tab, the method comprising the steps of engaging the tab with a pair of rigid sheets in contact with each other at their upper portions, from their one ends and in parallel with them, subsequently inserting the wire end into the tab while the pair of sheets are displaced apart from each other perpendicular to the tab, and finally disengaging the sheets from the tab, thus fitting an outer surface of the wire end in the tab. An apparatus used in the method comprises a wire receiving section, a tab receiving section, at least one of the sections moves relative to the other to come into or out of contact therewith, the wire receiving section including a wire end supporter and a terminal supporter disposed with a distance substantially equal to the tab, the tab receiving section including a pair of rigid sheets extending parallel with the wire received on the section, a tab-holding space formed above the sheets so as to hold the tab, an urging means disposed remote from said section so as to elastically press the marking portion, and a retracting means retracting the sheets out of the space.
摘要:
A crimping station of a motor-driven portable crimper (A) has a movable head driven by a motor (M) to reciprocate straight towards and away from a fixed anvil. An automatic switch will automatically stop the motor upon detection of the movable head retracted from or having approached the anvil, so that the head and other members stand still for a while relative to the fixed anvil to allow the wire end to be inserted readily into the contact and then the contact thus crimped can easily be withdrawn from the crimping station. A manual switch is operable to restart the motor and resume the crimping process. A blind plate attached to and outside the frame is disposed near the crimping station so as to inhibit a user from erroneously inserting wire ends to the contacts which have not arrived at the station.