| Yamada Manufacturing Co., Ltd. Patent applications |
| Patent application number | Title | Published |
| 20120024243 | Engine cooling apparatus - The present invention provides an engine cooling apparatus that is capable of suppressing cavitation in a high rotation region while achieving an increase in a circulation flow rate of cooling water in a low/medium rotation region. The engine cooling apparatus includes: a main cooling water circuit that circulates the cooling water between an engine and a radiator; a branch portion provided between the engine and the radiator; a thermostat; temperature detecting means; a first bypass flow passage; a second bypass flow passage that connects the engine to the branch portion; a control valve; a bypass convergence portion; a water pump; valve opening control means; and engine rotation speed detecting means. | 02-02-2012 |
| 20110255970 | Impeller for water pump - A present invention's object is to maintain a discharge performance by making a discharge flow rate constant in a low rotation region of an engine rotation speed and to reduce the discharge flow rate in a high rotation region. The present invention consists of a housing case, an impeller base provided with plural holes and plural elliptical elongated holes, a vane body provided with a rotary shaft on an inner peripheral side and a rocking shaft on an outer peripheral side, a plate cam in which an elongated groove is formed on an outer peripheral side of a disc portion and a single torsion spring. The spring and the plate cam are housed in the housing case and the impeller base. The rotary shaft is inserted rotatably into the holes, and the rocking shaft is movably inserted into the elliptical elongated holes and the elongated groove. | 10-20-2011 |
| 20110254410 | Electric water pump - In a circuit substrate of an electric water pump, a Hall IC can be mounted on a circuit substrate at an optimum position in a stable and durable state. The electric water pump includes a motor housing, a stator constituted by a stator core covered by a resin insulator and a coil, a circuit substrate, a holder | 10-20-2011 |
| 20110203403 | Steering position adjustment device - A spring for assisting a tilt adjustment operation can be easily and rapidly attached to a fixed bracket and a movable bracket. Each of two flanges of a fixed bracket has a tilted flange plate and a locking piece. The locking piece has a guiding edge, a locking recess, an insertion recess, and a fixing hole. In a spring member, a first locking shaft portion is formed on the rear side of two coil portions, and a second locking shaft portion is formed rearward from the distal end of the first locking shaft portion. The first locking shaft portion is engaged with the locking recess, and the second locking shaft portion is engaged with the fixing hole. The distance between the first locking shaft portions of the spring member is less that the distance between the two guiding edges. | 08-25-2011 |
| 20110175335 | STEERING DEVICE - Provided is a steering device in which play of a bolt shaft and the like during telescopic adjustment can be prevented using a telescopic adjustment function enabling a driver to adjust a position of a steering wheel in a front-rear direction. The steering device includes a column pipe, an outer housing, a fixed bracket, a stopper bracket, a tightening member having a bolt shaft, a slide guide, an elastic stopper rubber material mounted on the slide guide, and an elastic pushing member in which torsional coil spring portions are formed at both axial ends of a pushing shaft portion. The bolt shaft is passed through a tightening hole of the outer housing and a support hole of the fixed bracket along shaft support portions of the slide guide, and the elastic pushing member is locked and fixed to the fixed bracket. | 07-21-2011 |
| 20110077092 | Unbalance correction device of propeller shaft - The present invention provides a device for correcting an unbalance of a propeller shaft, specifically an unbalance correction device of a propeller shaft capable of securing a considerable amount of correction, reducing the generation of noise and the like, and preventing the adverse effect of welding heat caused by welding and fixing the balance weight from exerting on a vibration absorbing rubber member. The unbalance correction device of a propeller shaft is configured from a propeller shaft to which a damper is mounted, and a balance weight in which a primary weight plate part and an auxiliary weight plate part are formed continuously and integrally along a longitudinal direction, and a protruding piece is protrusively formed on a concave arced surface on a rear surface side of the primary weight plate part and from each corner part at four locations. The primary weight plate part is disposed in a non-mounted area of the damper at an axial direction end of the outer shaft with a longitudinal direction of the balance weight coinciding with an axial direction of the outer shaft, and the balance weight is configured such that only the protruding piece comes in contact with and is welded to an outer peripheral side face of the outer shaft. | 03-31-2011 |
| 20110027112 | Water pump - The present invention provides a water pump capable of minimizing the runout of a shaft of an impeller even if a bearing supporting the shaft is provided only at one location. This water pump includes a pump cover, a motor case having a partition wall part, an impeller that is rotatably housed in a pump chamber, a shaft, a radial bearing, a rotor base formed with a shaft connecting part to which the shaft is press-fitted and fixed, an inner magnet that is fixed to an outer periphery of the rotor base, and a stator core mounted in the motor case. A substantially cylindrical bearing housing part is formed in partition wall part, the radial bearing is inserted and fixed to the bearing housing part, the radial bearing is disposed in the rotor base, and an axial direction overall length of the radial bearing is positioned within a substantial area of an axial direction overall length of the inner magnet. | 02-03-2011 |
| 20100242663 | Steering apparatus - The present invention provides a steering apparatus which has increased rigidity in a fixed state of the steering column after positioning performed by tilt and telescopic adjustment, and in which a play is inhibited and operation feeling of steering is improved. The steering apparatus includes a fixed bracket, an outer column, an arm unit, an inner column, a steering shaft, and a tightening tool. The outer column is constituted by a main holding body portion, a divided portion, and a tightening portion. The arm unit is constituted by a bifurcated arm portion that extends axially outward in a substantially bifurcated shape at the axial front side of the main holding body portion and a linking portion formed between the arms of the bifurcated arm portion. The inner column is held by the outer column. The steering shaft is pivotally supported by the linking portion. Two tightening plate-like pieces of the tightening portion are disposed inside two fixed side portions of the fixed bracket and tightenably connected by the tightening tool. | 09-30-2010 |
| 20100242662 | Steering apparatus - The present invention provides a steering apparatus that can provide good operation feeling in telescopic adjustment and can have a very simple configuration. The steering apparatus has a fixed bracket, a movable bracket, a sliding shaft support member, and a tightening tool. The sliding shaft support member is constituted by a main sliding unit made of an inelastic resin and buffer portions made of a rubber or an elastic resin. The buffer portions are fixedly attached to both sides of the main sliding unit in the front-rear direction, the upper and lower surfaces of the main sliding unit are in a state of sliding contact with both guide edges of a long hole for telescopic adjustment of the movable bracket, and the buffer portions can abut only on both stop end edges and do not come into contact with the two guide edges. | 09-30-2010 |
| 20100242280 | Method for manufacturing closed impeller - The present invention provides a method for manufacturing a closed impeller that has a simple configuration and enables fusion in a very accurate position. The method includes: forming a frustum-shaped front plate and a disk-shaped base plate formed therebelow, upper surfaces of a plurality of unit impeller blade plates made from a synthetic resin extending in radial directions which are formed as impeller blade tip surfaces, with sharp-pointed ridge-like protrusions having an acute upper end and a width less than a width of the impeller blade tip surface being integrally formed on the impeller blade tip surfaces. In the method, an inner surface of the front plate and the plurality of impeller blade tip surfaces are formed as parts of conical surfaces and formed so that the cone apex angles of the two conical surfaces are equal to each other. Then, the front plate is placed on the impeller blade and the ends of the sharp-pointed ridge-like protrusions and the inner surface of the front plate are brought into contact with each other. Small vibrations are then provided while applying an appropriate pressurizing force between the front plate and the impeller blade having the base plate attached thereto, the sharp-pointed ridge-like protrusions are melted, and the front plate is fused to the tip surfaces of the impeller blade. | 09-30-2010 |
| 20100078085 | Relief valve structure - To provide a relief valve structure for an oil pump, which is capable of appropriately controlling/switching the discharge pressure and flow rate of oil to an optimum condition in low, middle and high speed regions of an engine. The relief valve structure has: a relief valve having formed therein a valve flow path for communicating between a valve head part and an outer circumferential side part; a valve housing in which a valve passage accommodating the relief valve is formed; a relief flow-in part formed on an axial direction one end side of the valve passage and communicating with the valve passage; a first discharge part formed in the valve housing and communicating with the valve flow path by the movement of the relief valve; and a second discharge part that is opened by allowing the valve head part to pass therethrough. The second discharge part is positioned nearer to the relief flow-in part than the first discharge part. The shortest gap between an outer circumferential side part opening of the valve flow path and the first discharge part is the same as or shorter than the shortest gap between the valve head part and the second discharge part during an initial state of the relief valve. | 04-01-2010 |
| 20090255488 | Cooling device for engine - A cooling device for an engine that can raise the temperature of cooling water within a short period of time during the warm-up operation and allows a simple structure. The cooling device has a radiator circulation flow channel for circulation via an engine, a radiator, and a thermostat; a heater circulation flow channel for circulation via the engine, a heater core, and the thermostat; a bypass circulation flow channel for circulation via the engine and the thermostat; an electronically controlled valve; and a pump. The radiator circulation flow channel, heater circulation flow channel, and bypass circulation flow channel merge in the thermostat and form a common flow channel between the thermostat and the engine. The pump is provided in the common flow channel. At the start of the warm-up period and during the warm-up operation, the circulation in the radiator circulation flow channel is substantially stopped by the thermostat, cooling water circulation is actuated in the bypass circulation flow channel, and an opening degree of the electronically controlled valve is gradually increased from a minimum as the cooling water temperature rises. At the end of the warm-up period, circulation is actuated in the radiator circulation flow channel and substantially stopped in the bypass circulation flow channel. | 10-15-2009 |
| 20090243229 | Packing material fitting structure - A packing material fitting structure that prevents the packing material from easily dropping out and facilitates mounting and fixing of the packing material in a packing material fitting place in a part such as a casing or a cover of an engine or a pump with sealing ability. The fitting structure is provided with a packing material having an annular main body portion and a plurality of projections each having a main protruding portion formed to protrude from the annular main body portion and an auxiliary protruding portion formed integrally in the vicinity of the main protruding portion, the projections being formed with an appropriate spacing in the longitudinal direction of the main annular main body portion. The fitting structure is also provided with a casing having formed therein an annular fitting groove for inserting the annular main body portion of the packing material. A cutout portion into which only the main protruding portion of the projection is inserted is formed in a groove wall portion of the fitting groove. An integral forming region of the auxiliary protruding portion and the annular main body portion has a width substantially equal to or larger than a width of the fitting groove. In the packing material, a projection formation location is pressed and fixed only by the cutout portion and both groove wall portions in the vicinity of the cutout portion. | 10-01-2009 |
| 20090185940 | Method for manufacturing trochoid pump and trochoid pump obtained - The present invention enables the manufacture of a trochoid pump having a crescent which has been considered theoretically impossible by employing an inner rotor of a trochoid pump. An inner rotor having a predetermined number N of teeth that is equal to or larger than 4 is formed in advance. In order to manufacture an outer rotor with a predetermined number (N plus a natural number equal to or larger than 2) of teeth, row circles that are identical to a drawn circle are disposed so as to bring the row circles into contact with the tooth bottomland of the inner rotor tooth profile, the inner rotor tooth profile is rotated by half a tooth about the center of the inner rotor and the outer rotor tooth profile is also rotated by half a tooth of the predetermined number (N plus a natural number equal to or larger than 2) of teeth about a virtual center of the outer rotor including the row circles, an established center is determined from the virtual center or the like at the time at which the contact state is assumed, a reference circle is drawn that has a radius from the established center to the row circles and that has the total predetermined number (N plus a natural number equal to or larger than 2) of the equidistantly spaced row circles to form the row circles as outer rotor tooth tips, thereby manufacturing the outer rotor tooth profile. | 07-23-2009 |
| 20090129950 | Oil pump resonator - The invention provides an oil pump resonator in which various vibrations caused by pulsations that change in response to changes in oil pressure on a discharge port side can be attenuated by a resonator that comprises only one chamber, whereby the volume occupied by the resonator can be minimized. An oil pump in an engine, for feeding oil from a suction port to a discharge port through rotation of a rotor fitted in a pump housing, includes: a discharge flow channel communicating with the discharge port; a resonator comprising an introduction channel formed in the discharge flow channel and a chamber communicating with the introduction channel; and a piston having a leading end face section that makes up an inner wall face of the chamber, and reciprocating in response to pulsation changes. The piston slides so as to reduce the volume of the chamber as the frequency distribution of the pulsations becomes higher. | 05-21-2009 |
| 20090104064 | Method for manufacturing trochoid pump and trochoid pump obtained - The present invention enables the manufacture of a trochoid pump having a crescent which has been considered theoretically impossible, by employing an inner rotor of a trochoid pump. An inner rotor having a predetermined number N of teeth that is equal to or larger than 4 is formed in advance. In order to manufacture an outer rotor with a predetermined number (N plus a natural number equal to or larger than 2) of teeth, row circles of a diameter slightly smaller than that of a drawn circle are disposed so as to bring the row circles into contact with the tooth bottomland of the inner rotor tooth profile, the inner rotor tooth profile is rotated by half a tooth about the center of the inner rotor and the outer rotor tooth profile is also rotated by half a tooth of the predetermined number (N plus a natural number equal to or larger than 2) of teeth about a virtual center of the outer rotor including the row circles, an established center is determined from the virtual center or the like at the time at which the contact state is assumed, a reference circle is drawn that has a radius from the established center to the row circles and that has the total predetermined number (N plus a natural number equal to or larger than 2) of the equidistantly spaced row circles to form the row circles as outer rotor tooth tips, thereby manufacturing the outer rotor tooth profile. | 04-23-2009 |
| 20090066070 | Tilt telescopic steering device - An object of the present invention is to markedly increase the tilt holding force of a tilt telescopic column. A tilt telescopic steering device includes: a fixed bracket | 03-12-2009 |
| 20090044657 | Steering wheel position adjustment device - A steering wheel position adjustment device includes a movable bracket having adjusting long holes on both sides in a width direction of the movable bracket, a fixed bracket, a lock shaft penetrating through both of the adjusting long holes to support the movable bracket to the fixed bracket, a collar member which is rotatably supported within the movable bracket by the lock shaft and is capable of moving along, with the lock shaft, in a longitudinal direction and stopper shock-absorbing materials, which are attached to both side sections in the longitudinal direction of the adjusting long holes within the movable bracket, and each of which is formed thereon with an abutment surface against which the collar member abuts. | 02-19-2009 |
| 20090010791 | Internal gear pump - An internal gear pump which has a crescent disposed between an outer rotor and an inner rotor having a trochoidal tooth profile, and which reduces vibrations caused by pulsations generated when the fluid is discharged. The internal gear pump has an outer rotor having internal teeth formed therein, an inner rotor disposed on the inner peripheral side of the outer rotor and having formed therein external teeth that mesh with the internal teeth, and a crescent disposed in a clearance between the outer rotor and the inner rotor. Pitch spacings of the external teeth of the inner rotor are formed as non-equal spacings, and pitch spacings of the internal teeth of the outer rotor correspond to the pitch spacings of the external teeth of the inner rotor. | 01-08-2009 |
| 20080282832 | Tilt steering apparatus - A tilt steering apparatus comprises a tilt adjusting mechanism in which a tilt lock release is established only when an oscillation-free end of an operating arm portion of a tilt operating lever is positioned toward a steering wheel side. Even when the tilt operating lever is oscillated to the steering wheel side, the tilt operating lever is prevented from returning under its own weight, thereby preventing it from being difficult to operate. The tilt steering apparatus is configured from an oscillation latch portion formed on the circumference of an oscillation center portion of an oscillation base portion of the tilt operating lever to move reciprocally in the circumferential direction, a hook portion formed in the movable bracket, and a spring that extends between the oscillation latch portion and the hook portion elastically urged in the direction of contraction. The centerline of the spring is able to pass through the oscillation center portion of the tilt operating lever as appropriate. | 11-20-2008 |
| 20080253904 | Oil pump pressure control device - A device for reducing friction in a variable flow rate oil pump in which two discharge ports are provided and which uses three rotors while maintaining characteristics identical to the pressure characteristics of a common oil pump. The device is configured from a first discharge passage to an engine, a return passage that returns to an intake side of an outer circumferential side rotor, a second discharge passage to the engine, a return passage that returns to an intake side of an inner circumferential side rotor, and a pressure control valve whose valve main body is provided between a discharge port from the inner circumferential side rotor and the first discharge passage. The first discharge passage and second discharge passage are coupled, and a flow passage control is executed in each of: a low revolution range in a state in which only the first discharge passage and the second discharge passage are open; an intermediate revolution range in a state in which the first discharge passage and second discharge passage are open and a first intake side of the return passage is closed while a second intake side of the return passage is open; and a high revolution range in a state in which the second discharge passage is closed while the first discharge passage and the return passage are open. | 10-16-2008 |
| 20080226484 | Internal gear pump - To provide an internal gear pump capable of preventing small vibrations due to pressure differences at the outlet port side of a crescent disposed between the outer rotor and the inner rotor, so that fatigue failure does not occur in the crescent over a long time period, whereby the durability can be increased. The internal gear pump includes a rotor unit, in which an inner rotor is disposed within an outer rotor on the inner peripheral side and a crescent is disposed in the gap between the inner rotor and the outer rotor, the rotor unit being housed in a pump casing. Outer cells are formed by the crescent and the outer rotor. Inner cells are formed by the crescent and the inner rotor. Linking of the outer cells and the outlet port, and linking of the inner cells | 09-18-2008 |