JP2009008158A - Solenoid valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a solenoid valve provided with pressure regulation capacity of directly supplying output hydraulic pressure to a hydraulic servo of a friction engagement element and capable of miniaturizing a hydraulic pressure control device. <P>SOLUTION: An inner valve part 30<SB>1</SB>is provided at a valve part 20<SB>1</SB>of a linear solenoid valve 1<SB>1</SB>, and an induction hydraulic oil path 21d establishing communication between a working hydraulic oil chamber 33 of the inner valve 30<SB>1</SB>and an output port Pout. A position of a second spool 31 is changed over between a case that output hydraulic pressure acting on the working hydraulic oil chamber 33 via the induction hydraulic oil path 21d is less than predetermined pressure and a case that the pressure is not less than the predetermined pressure. Since action of feed back pressure on a feed back hydraulic oil chamber 27 is turned on in a low hydraulic pressure output zone where a slip state of a friction engagement element is controlled and action of the feed back pressure is turned off in a high hydraulic pressure zone where fine control of the friction engagement element is not necessary, drive force performance necessary for the solenoid part 10 is reduced and the device can be miniaturized. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a solenoid valve that can electrically regulate and output an input hydraulic pressure, and more particularly, to a solenoid valve used in a hydraulic control device of an automatic transmission for a vehicle.

  2. Description of the Related Art Conventionally, for example, in a hydraulic control device for an automatic transmission for a vehicle, the hydraulic pressure generated by an oil pump is regulated to a line pressure corresponding to a throttle opening by a regulator valve, and the line pressure is applied to a frictional engagement such as a clutch or a brake. By selectively supplying to the hydraulic servo of the combined element, the friction engagement elements are selectively engaged to form a power transmission path, and the output torque of the drive source increases as the throttle opening increases Thus, the friction engagement element is configured not to slip.

  When the line pressure is supplied to the hydraulic servo of the friction engagement element for engagement or release and release is performed, the line pressure is simply supplied to or discharged from the hydraulic servo, so Since a shift shock due to release occurs, it is necessary to supply and discharge the hydraulic servo while adjusting the line pressure to a desired pressure. Therefore, an oil passage for supplying the line pressure to the hydraulic servo is provided with a control valve that can control the throttle amount of the line pressure relative to the hydraulic servo by moving the spool according to the input control pressure. The control pressure is generated with respect to the control valve by electrically controlling the linear solenoid valve by generating the control pressure with the linear solenoid valve using the modulator pressure with the line pressure suppressed below the predetermined pressure by the modulator valve. The hydraulic pressure supplied to the hydraulic servo is controlled by adjusting the line pressure using the control valve (see Patent Document 1 and FIG. 5).

JP 2003-74733 A

  By the way, in recent years, the automatic transmission has been developed in a multi-stage manner in order to improve the fuel consumption, and the number of friction engagement elements has increased accordingly. Therefore, in the hydraulic control device of the automatic transmission, when the control valves as described above are provided corresponding to each friction engagement element, not only the number of these control valves increases, but also the oil passage becomes complicated, The size of the hydraulic control device will be increased.

  For this reason, without using the control valve as described above, the line pressure is used as the input hydraulic pressure of the linear solenoid valve, and the output hydraulic pressure from the linear solenoid valve is directly applied to the hydraulic servo of the friction engagement element (other valves). It is conceivable to adjust the supply hydraulic pressure of the hydraulic servo using only the linear solenoid valve.

  However, in order to supply hydraulic pressure directly from the linear solenoid valve to the hydraulic servo in this way, the line pressure is overwhelmingly higher than the modulator pressure. There is a problem that it is necessary to greatly increase the driving force of the plunger of the linear solenoid valve, which leads to an increase in the size of the solenoid part and eventually an increase in the size of the hydraulic control device. .

  On the other hand, for example, a linear solenoid valve used in an automatic transmission requires fine control in a low hydraulic output region in order to prevent a shift shock during a shift, and on the contrary, engages a friction engagement element. In a high hydraulic output region for maintaining the state, there is a characteristic that high output is simply required. Therefore, feedback control is performed in such a low hydraulic output region, and feedback action is eliminated by turning off (cutting) the feedback pressure input in a high hydraulic output region, thereby increasing the size of the linear solenoid valve. It is conceivable to improve the output capability without doing so. However, in order to turn on / off the feedback pressure in this way, a switching valve or the like for turning on / off the feedback pressure is separately provided, which increases the number of valves and eventually enlarges the hydraulic control device. Invitation

  Accordingly, an object of the present invention is to provide a solenoid valve having a pressure adjustment capability capable of directly supplying output hydraulic pressure to a hydraulic servo of a friction engagement element and capable of reducing the size of a hydraulic control device. It is what.

According to the first aspect of the present invention (see, for example, FIGS. 1 to 6), the solenoid unit (10) that drives the plunger (11) according to the supplied electric power and the driving force of the plunger (11) are the first. By moving the first spool (21) against the urging force of the urging means (24), the opening amount between the input port (Pin) to which the input hydraulic pressure is input and the output port (Pout) is adjusted. A solenoid valve (1) having a feedback oil chamber (27) that feeds back an output hydraulic pressure output from the output port (Pout) in a direction to reduce the opening amount;
A feedback pressure introduction oil passage (22B, 21e, 39B) capable of introducing the output hydraulic pressure into the feedback oil chamber (27);
A second spool (31) movably disposed in a hollow portion (21A) formed in the first spool (21);
A second urging means (32) for receiving a reaction force by the first spool (21) and urging the second spool (31) to one side in the moving direction;
A hydraulic oil chamber (33) in which the input hydraulic pressure opposes the second spool (31) against the urging force of the second urging means (32);
An introduction oil passage (21d) formed in the first spool (21) and communicating the output port (Pout) and the hydraulic oil chamber (33) to introduce the output hydraulic pressure into the hydraulic oil chamber (33). )When,
A drain port (Pex2) capable of discharging the oil in the feedback oil chamber (27),
When the output oil pressure acting on the hydraulic oil chamber (33) via the introduction oil passage (21d) is less than a predetermined pressure (for example, P1), the second spool (31) has the feedback oil chamber ( 27) and the drain port (Pex2) are shut off, and the feedback oil chamber (27) and the feedback pressure introduction oil passage (22B, 39B) are communicated with each other via the introduction oil passage (21d). When the output oil pressure acting on the hydraulic oil chamber (33) is equal to or higher than a predetermined pressure (for example, P1), the feedback oil chamber (27) and the feedback pressure introduction oil passage (22B, 39B) are shut off. The feedback oil chamber (27) and the drain port (Pex2) are in communication with each other.
The solenoid valve (1) is characterized by that.

According to a second aspect of the present invention (see, for example, FIGS. 1 and 3), the feedback pressure introducing oil passage is formed in a first sleeve member (22) fitted to the first spool (21). An oil passage (22B) in the sleeve, and a feedback input port (21e) formed in the first spool and communicating with the oil passage (22B) in the first sleeve.
The solenoid valve (1 ₁ , 1 ₂ ) according to claim 1.

The present invention according to claim 3 (see, for example, FIGS. 5 and 6) is interposed between the inner periphery of the hollow portion (21A) of the first spool (21) and the outer periphery of the second spool (31). A second sleeve member (39),
The feedback pressure introduction oil passage is formed in the second sleeve member (39), and from the second sleeve oil passage (39B) capable of communicating the hydraulic oil chamber (33) and the feedback oil chamber (27). Become,
The solenoid valve (1 ₃ , 1 ₄ ) according to claim 1.

According to the fourth aspect of the present invention (see, for example, FIGS. 1, 2, and 5), the biasing force of the first biasing means (24) when the solenoid part (10) is in a non-energized state. Is a normally closed type in which the input port (Pin) and the output port (Pout) are blocked by the first spool (21).
The solenoid valve (1 ₁ , 1 ₃ ) according to any one of claims 1 to 3.

According to the fifth aspect of the present invention (see, for example, FIGS. 3, 4, and 6), the biasing force of the first biasing means (24) when the solenoid part (10) is in a non-energized state. Is a normally open type in which the input port (Pin) and the output port (Pout) are communicated with each other by the first spool (21).
The solenoid valve (1 ₂ , 1 ₄ ) according to any one of claims 1 to 3.

The present invention according to claim 6 is used in a hydraulic control device for an automatic transmission capable of supplying an output hydraulic pressure output from the output port (Pout) to a hydraulic servo of a friction engagement element.
It exists in the solenoid valve (1) in any one of Claim 1 thru | or 5.

  In addition, although the code | symbol in the said parenthesis is for contrast with drawing, this is for convenience for making an understanding of invention easy, and has no influence on the structure of a claim. It is not a thing.

  According to the first aspect of the present invention, the second spool that is switched to a position where the feedback pressure introducing oil passage and the feedback oil chamber are communicated and blocked, and the second urging means that urges the second spool are provided. Since the first spool is provided with an introduction oil passage which is arranged in a hollow portion in one spool and introduces the output hydraulic pressure of the output port into the hydraulic oil chamber of the second spool, when the output hydraulic pressure is less than a predetermined pressure, It can be configured such that the feedback pressure is turned off when the feedback pressure is applied and the output hydraulic pressure becomes equal to or higher than a predetermined pressure.

  Thus, for example, without providing a control valve or the like, and without enlarging the solenoid portion, the solenoid valve has the ability to sufficiently regulate the output hydraulic pressure as the hydraulic servo supply hydraulic pressure of the friction engagement element. In addition, it is not necessary to separately provide a switching valve for turning on and off the feedback pressure, and the hydraulic control device can be reduced in size comprehensively.

  According to the second aspect of the present invention, the feedback pressure introduction oil passage includes a first sleeve oil passage formed in the first sleeve member fitted into the first spool, and a feedback input port formed in the first spool. Therefore, it is not necessary to provide an oil passage for guiding the feedback pressure to the feedback oil chamber in the hydraulic control device, and the hydraulic control device can be downsized. Further, for example, the first sleeve member oil passage can be formed by a simple process in which two holes are formed in the first sleeve member, and a groove for communicating these two holes is formed in the outer peripheral portion. In addition, the feedback input port can be formed by a simple process of simply drilling a hole at the corresponding position of the first spool, that is, the feedback pressure introducing oil passage can be configured by a simple process.

  According to the third aspect of the present invention, the feedback pressure introduction oil passage is formed in the second sleeve member and is formed of the second sleeve oil passage capable of communicating the hydraulic oil chamber and the feedback oil chamber. It is unnecessary to provide an oil passage for guiding the feedback pressure to the feedback oil chamber, and the hydraulic control device can be downsized. Further, for example, a second sleeve internal oil passage is formed in the second sleeve member, and the second sleeve member is interposed between the inner peripheral side of the hollow portion of the first spool and the outer peripheral side of the second spool. As a result, the feedback pressure introduction oil passage can be configured, that is, the assembly process can be simplified.

  According to the fourth aspect of the present invention, since the solenoid valve is of a normally closed type, it is possible to reduce power consumption when outputting the maximum output hydraulic pressure, for example, when maintaining the engagement state of the friction engagement element. The energy efficiency of the hydraulic control in can be improved, and the fuel efficiency of the vehicle can be improved.

  According to the fifth aspect of the present invention, since the solenoid valve is a normally open type, it is possible to reduce power consumption when the output hydraulic pressure is not output, for example, when maintaining the released state of the friction engagement element. The energy efficiency of the hydraulic control in can be improved, and the fuel efficiency of the vehicle can be improved.

  According to the sixth aspect of the present invention, the solenoid valve is preferably used in a hydraulic control device for an automatic transmission that can supply the output hydraulic pressure output from the output port to the hydraulic servo of the friction engagement element. it can.

<First Embodiment>
Hereinafter, a first embodiment according to the present invention will be described with reference to FIGS. 1 and 2. FIG. 1 is a cross-sectional view showing a normally closed type linear solenoid valve according to the first embodiment, and FIG. 2 is a diagram showing a relationship between current and output hydraulic pressure in the linear solenoid valve according to the first embodiment. .

A linear solenoid valve (solenoid valve) 1 ₁ according to the first embodiment, as shown in FIG. 1, consists roughly solenoid portion 10 and the valve unit 20 ₁ Tokyo, the valve portion 20 _one of which, for example, automatic It is installed so as to be fitted and embedded in the valve hole 99A of the valve body 99 in the hydraulic control device of the transmission.

  The solenoid unit 10 includes a plunger 11, a coil assembly 17, and a case 13 (hereinafter referred to as “yoke”) that functions as a yoke. The coil assembly 17 includes a bobbin 12b made of a nonmagnetic metal such as stainless steel (SUS) (not necessarily a metal but may be a nonmagnetic material such as a synthetic resin), a magnet wire (not shown), and electromagnetic soft iron. End portions 15 and 16 that are made of a ferromagnetic material such as a magnetic material and a terminal 14 that supplies a current to a coil 12a around which the magnet wire is wound around the bobbin 12b. The end portions 15 and 16 are disposed at both axial end portions of the bobbin 12b. Both the end portions 15 and 16 and the bobbin 12b are integrally formed by sintering bonding. The electromagnetic soft iron that constitutes the end part preferably contains pure iron of 95 [%] or more, preferably about 99 [%] or more (rounded to the first decimal place, 99 [%] or more). Moreover, although the both end parts 15 and 16 and the bobbin 12b are demonstrated as what is integrally formed by sintering coupling, you may form integrally by welding, brazing, adhesion | attachment, etc.

  The coil assembly 17 is formed in a cylindrical shape excluding the terminal 14 portion, and a hollow portion 17a having the same diameter in the axial direction is formed at the center of the assembly 17. The plunger 11 is slidably inserted into the hollow portion 17a. The plunger 11 has an outer peripheral surface having the same diameter in the axial direction and is longer in the axial direction than the coil 12a.

  The end portion 15 of the coil assembly 17 is formed with an edge portion 15 a that is tapered toward the plunger 11 and has a triangular shape in cross section at the inner peripheral side. An annular step portion 15b is formed at the root portion of the edge portion 15a of the end portion 15, and serves as a locking portion that is sintered and joined to the flange portion 12c of the bobbin 12b. On the other hand, a cylindrical portion 16a is formed on the bobbin 12b side of the end portion 16 and serves as a locking portion that is sintered and joined to the annular portion 12d of the bobbin 12b.

  That is, when the bobbin 12b and the end portions 15 and 16 are heated and sintered, the bobbin 12b made of, for example, stainless steel contracts, and the end portions 15 and 16 that are made of, for example, soft iron and do not substantially contract, and the bobbin 12b. Between the particles, the flange portion 12c is joined to the step portion 15b and the annular portion 12d is joined to the cylindrical portion 16a while being pressed against each other. As a result, the bobbin 12b and the end portions 15 and 16 are integrally formed with a high bonding strength.

  The edge portion 15a preferably has the right-angled triangular shape described above, but the inner diameter surface may be a curved surface or a multi-step inclined surface having different inclination angles. In short, magnetic saturation appears toward the tip of the edge portion 15a. Any tapered shape is acceptable.

On the other hand, a distal end 19a of a plug 19 described later is in contact with one end surface 11b of the plunger 11. Further, on the side of the other end surface 11c away from the valve unit 20 ₁ in the plunger 11, the coating or surface treatment of the non-magnetic material has been applied, the plunger 11 and the yoke 13 are disconnected magnetically. A projection 13c is formed on the inner central portion of the bottom portion of the yoke 13 toward the plunger 11, and the other end surface 11c is configured to partially abut against the yoke 13. Thereby, the plunger 11 is prevented from adsorbing to the bottom portion of the yoke 13. It should be noted that not only the plunger end surface (the other end surface 11c) but also a non-magnetic coating or surface treatment may be applied to the bottom of the yoke 13. In short, the magnetic poles of the yoke 13 and the plunger 11 are separated in the mounted state. I can do it.

  The plunger 11 has a plurality of through holes 11a and 11a penetrating between the one end surface 11b and the other end surface 11c, and oil in a space formed by being separated by a diaphragm 18 to be described later. When the plunger 11 is driven and moved, the plunger 11 passes and flows into a gap formed between the other end surface 11 c of the plunger 11 and the yoke 13. That is, the through holes 11a and 11a are configured so that resistance due to volume change is less likely to occur when the plunger 11 is driven.

The yoke 13 is made of a ferromagnetic material, is formed in a cup shape by plastic metal processing such as deep drawing or cold forging, and a part 13a is notched for the terminal 14. The material of the yoke 13 is desirably an electromagnetic soft iron containing pure iron of 95 [%] or more, preferably approximately 99 [%] or more (rounded to the first decimal place and 99 [%] or more). The yoke 13, the pay within the coil assembly 17 fitted, and by the leading end portion is fixed to an end portion of the sleeve portion of the valve portion 20 ₁ (first sleeve member) 22 to be described later, the solenoid unit 10 is assembled integrally with the valve portion 20. Also, during this assembly, the plug 19 is arranged in a manner to be interposed between the first spool 21 of the valve unit 20 ₁ described below with the plunger 11, is secured to the outer periphery of the plug 19 The diaphragm 18 is attached so as to be sandwiched between the sleeve portion 22 and the end portion 15.

On the other hand, the valve unit 20 _1, the entire sleeve portion 22 formed in a substantially sleeve-shaped, and is fitted into (movable relative to the longitudinal direction) slidably in a hollow portion 22A of the sleeve 22 A first spring (first biasing means) is provided between an end cap 23 secured to and secured to the sleeve portion 22 and a washer 25 secured to a tip portion of the first spool 21. ) 24 is contracted.

  The sleeve portion 22 includes, in order from the top in the figure, a drain port Pex1 for draining (discharging) output hydraulic pressure supplied to a hydraulic servo (not shown), an output port Pout communicating with the hydraulic servo (not shown), and a throttle opening degree. The input port Pin to which the line pressure adjusted in accordance with the pressure (including the range pressure supplied via a manual valve for switching the shift range) is input, and the drain port that can drain the hydraulic pressure of the feedback oil chamber 27 described later A drain port Pex3 that is opened so as not to hinder the movement of the first spool 21 is formed.

  Further, an opening portion is closed by a valve body 99 between the input port Pin and the drain port Pex2, that is, on the opposite side of the solenoid portion 10 with respect to the input port Pin, and will be described later. A feedback oil chamber 27 is formed in which the oil pressure input by the difference in the land diameter of the spool 21 acts as a feedback pressure. The sleeve portion 22 is drilled from the outer peripheral side at a position corresponding to an oil hole 22a drilled from the outer peripheral side toward the output port Pout and a feedback input port 21e of the first spool 21 described later. An oil hole 22c and a groove 22b communicating with the two oil holes 22a and 22c are formed, and the outer peripheral side of the groove 22b is closed by the valve body 99, so that feedback pressure to be described in detail later is fed back. A sleeve oil passage (feedback pressure introduction oil passage, first sleeve oil passage) 22B that can be introduced into the oil chamber 27 is configured.

  In the valve body 99, oil passages 99a, 99b, 99c, 99d, and 99e are formed at positions corresponding to these ports Pex1, Pout, Pin, Pex2, and Pex3, and communicated with these ports. That is, the oil passages 99a, 99d, and 99e are oil passages that discharge oil toward an oil pan (not shown), and the oil passage 99c communicates with a pressure regulating port of a regulator valve that regulates a line pressure (not shown). The oil passage 99b is an oil passage that communicates with the hydraulic oil chamber of the hydraulic servo of the friction engagement element (clutch or brake).

  The first spool 21 has two large-diameter land portions 21a and 21b and one small-diameter land portion 21c. A hole portion 21h is formed on the plunger 11 side of the large-diameter land portion 21a. Thus, the bottom surface of the hole portion 21h is in contact with the end portion 19b formed in the curved shape of the plug 19. That is, the first spool 21 is configured to be pressed and driven through the plug 19 by the plunger 11 of the solenoid unit 10 against the urging force of the first spring 24.

  The large-diameter land portions 21a and 21b are formed to have an outer diameter d1 larger than the outer diameter d2 of the small-diameter land portion 21c. Among the large-diameter land portions 21a, the solenoid portion 10 is not energized and When the 1 spool 21 is in a position biased by the first spring 24 without being pressed by the plunger 11, the output port Pout and the drain port Pex1 are communicated with each other when the plunger 11 is pressed and moved. The output port Pout and the drain port Pex1 are cut off.

  The large-diameter land portion 21b blocks the input port Pin and the output port Pout and presses the plunger 11 when the first spool 21 is in a position biased by the first spring 24 without being pressed by the plunger 11. When it is moved, the opening amounts of the input port Pin and the output port Pout are increased.

  The large-diameter land portion 21b and the small-diameter land portion 21c are formed so as to be positioned in the feedback oil chamber 27 even when the first spool 21 is moved. The feedback pressure input to the feedback oil chamber 27 acts in the same direction as the urging direction of the spring 24 due to the outer diameter difference (d1-d2) from the portion 21c, that is, the output port Pout and the input port Pin. It is comprised so that it may act in the direction where the opening amount of becomes small.

In the first spool 21, a hollow hole (hollow part) 21A is formed in the large-diameter land portion 21b and the small-diameter land portion 21c, and an internal valve is formed in the hollow hole 21A. part 30 ₁ is formed. Washer or inner valve portion 30 ₁ is slidably in a hollow hole 21A has a second spool 31 that is fitted into (movable relative to the longitudinal direction), which is fixed to the first spool 21 A second spring (second urging means) 32 is contracted between 25 and a hole 31 c formed at the tip of the second spool 31. The second spool 31 is formed with a first land portion 31a, a second land portion 31b, and a shaft portion 31d that connects both the land portions 31a and 31b, and the first land portion 31a and the hollow hole 21A. A hydraulic oil chamber 33 is formed between the bottom portion on the upper side in the figure. An oil hole 21d is formed in the first spool 21 from an oblique direction with respect to the end of the large-diameter land portion 21b, and the output port Pout communicates with the hydraulic oil chamber 33 through the oil hole 21d. It is, that the hydraulic oil chamber 33 is present linear solenoid valve 1 ₁ output hydraulic is configured to be guided.

  On the other hand, a position corresponding to the first land portion 31a of the second spool 31 in the large-diameter land portion 21b of the first spool 21 is always in communication with the oil passage 22B in the sleeve regardless of the movement position of the first spool 21. The feedback input port 21e is formed by drilling, and these constitute a feedback pressure introduction oil passage that guides the output hydraulic pressure of the output port Pout as a feedback pressure.

  An oil hole 21g is formed in the hollow hole 21A between the large-diameter land portion 21b and the small-diameter land portion 21c, and the first land portion 31a of the second spool 31 receives the feedback input. In a state where the port 21e is opened (a state where the second spool 31 is moved upward in the figure), the feedback pressure guided to the feedback input port 21e is caused by a gap between the hollow hole 21A and the shaft portion 31d. The oil is guided to the feedback oil chamber 27 through the formed oil passage 34 and the oil hole 21g.

  Further, a drain port 21f that always communicates with the drain port Pex2 of the sleeve portion 22 is located at a position corresponding to the second land portion 31b of the second spool 31 in the small-diameter land portion 21c regardless of the movement position of the first spool 21. In the state where the second land portion 31b of the second spool 31 opens the drain port 21f (the state where the second spool 31 is moved downward in the figure). The feedback pressure in the feedback oil chamber 27 is drained through the oil hole 21 g and the oil passage 34.

Next, a description will be given of the operation of the linear solenoid valve 1 ₁ Based on the configuration described above. When electric power is supplied from the terminal 14 to the magnet wire (hereinafter referred to as “electric power is supplied to the solenoid unit 10”), the bobbin 12b made of a non-magnetic material does not constitute a magnetic circuit, and thus is made of a ferromagnetic material. , A magnetic circuit that flows through the yoke 13, one end portion 15, the plunger 11, and the other end portion 16 is formed. Based on the magnetic circuit, one end surface 11b of the plunger 11 and the end portion 15 serve as a suction portion, and the plunger 11 is attracted to the end portion 15 and driven downward in the figure. Then, based on the stroke amount of the plunger 11, the first spool 21 moves against the first spring 24 through the plug 19, and the position of the first spool 21 with respect to the sleeve portion 22 is controlled.

  When the electric power supplied to the terminal 14 is zero, that is, in a non-energized state, the plunger 11 is not stroke driven, and the first spring 21 and the plug 19 are driven by the urging force of the first spring 24. The plunger 11 is at the upper position in the figure. Then, the line pressure supplied to the input port Pin is interrupted by the large-diameter land portion 21b, and the output port Pout is communicated with the drain port Pex1 based on the position of the large-diameter land portion 21a. Supply hydraulic pressure) is drained.

  At this time, the hydraulic pressure in the hydraulic oil chamber 33 communicating with the output port Pout by the oil hole 21d is also zero, and further, the oil pressure is output via the oil path 22B in the sleeve, the feedback input port 21e, the oil path 34, and the oil hole 21g. The oil pressure in the feedback oil chamber 27 communicating with the port Pout is also zero.

  Next, when the supply of electric power to the solenoid unit 10 is started, the plunger 11 is stroked (driven) downward in the figure, and the plug 19 and the first spool 21 resist the urging force of the first spring 24 in the figure. Moved downward. Then, the drain port Pex1 is closed by the large-diameter land portion 21a, and the input port Pin and the output port Pout are opened and communicated with each other by the movement of the large-diameter land portion 21b to increase the opening amount. As a result, the line pressure of the input port Pin is supplied to the output port Pout while being narrowed based on the opening amount, and the output hydraulic pressure is output from the output port Pout to a hydraulic servo (not shown).

  At this time, if the power supplied to the solenoid unit 10 is less than the predetermined current value Ax shown in FIG. 2, that is, the output hydraulic pressure is less than the hydraulic pressure (predetermined pressure) P1, and the oil pressure is passed through the oil passage 21d. The output hydraulic pressure acting on the hydraulic oil chamber 33 is smaller than the urging force of the second spring 32, the relative position of the second spool 31 to the first spool 21 is on the upper side in the figure, and the second spool 31 Since the one land portion 31a opens the feedback input port 21a of the first spool 21 without closing it, the output hydraulic pressure of the output port Pout is fed to the feedback input port of the first spool 21 via the in-sleeve oil passage 22B. 21e, and further led to the feedback oil chamber 27 through the oil passage 34 and the oil hole 21g.

In this state, the driving force of the plunger 11, the biasing force of the first spring, and the feedback force of the feedback oil chamber act on the first spool 21, and respond to the increase in the current supplied to the solenoid unit 10. As the output hydraulic pressure rises and the feedback pressure rises in proportion to the output hydraulic pressure, the relationship between the output hydraulic pressure and the electric power has a gradient as shown by X1 _{N / C} (feedback ON state) in FIG. It is a gentle direct proportional relationship. Accordingly, it is necessary to finely control the output hydraulic pressure supplied to a hydraulic servo (not shown), for example, in the low hydraulic pressure region up to the engagement hydraulic pressure P1 at which the friction engagement element is completely engaged. Engagement control such as the slip state of the joint element can be performed with high accuracy.

  Subsequently, when the electric power supplied to the solenoid unit 10 becomes equal to or higher than the predetermined current value Ax shown in FIG. 2, that is, the output hydraulic pressure becomes equal to or higher than the hydraulic pressure (predetermined pressure) P1, and the operation is performed via the oil passage 21d. The output hydraulic pressure acting on the oil chamber 33 becomes larger than the urging force of the second spring 32, the relative position of the second spool 31 with respect to the first spool 21 is switched to the lower side in the figure, and the second spool 31 One land portion 31 a closes the feedback input port 21 a of the first spool 21. As a result, the output hydraulic pressure led to the feedback input port 21e of the first spool 21 via the in-sleeve oil passage 22B is cut off, that is, no feedback pressure is supplied to the feedback oil chamber 27. Further, the second land portion 31b of the second spool 31 opens the drain port 21f of the first spool 21, and the feedback oil chamber 27 communicates with the drain port Pex2 via the oil hole 21g, the oil passage 34, and the drain port 21f. In other words, the feedback pressure supplied in the feedback oil chamber 27 is drained to zero.

In this state, the feedback force on the first spool 21 does not act, and only the driving force of the plunger 11 and the urging force of the first spring act on the first spool 21. As a result, the relationship between the output hydraulic pressure and the electric power is a direct proportional relationship having a steep slope as compared with the above X1 _{N / C} as shown by X2 _{N / C} (feedback OFF state) in FIG. Therefore, fine control of the output hydraulic pressure supplied to the hydraulic servo (not shown) is no longer necessary. For example, in the high hydraulic pressure region from the engagement hydraulic pressure P1 to the engagement hydraulic pressure P2, the output hydraulic pressure is suddenly increased or decreased. Can be planned. The hydraulic pressure P2 is substantially the same as the line pressure, and is a pressure that takes into account a safety factor that prevents the frictional engagement element from slipping due to, for example, a sudden torque fluctuation that the driving wheel receives from the road surface. Full engagement pressure.

As described above, in the present linear solenoid valve 1 _1, it can be performed by the internal valve unit 30 ₁ by automatic switching based on the output hydraulic feedback pressure on and off, conventional in FIG As shown in the relationship Y _{N / C} between the output hydraulic pressure and the current, the current A2 required for setting the output hydraulic pressure to the full engagement pressure P2 can be reduced to the current A1. That is, the maximum driving force performance of the plunger 11 of the solenoid unit 10 can be reduced from the driving force corresponding to the current A2 to the driving force corresponding to the current A1, and accordingly, the coil assembly 17 of the solenoid unit 10 and the like. The size can be made compact.

Thus, for example, without providing a control valve for controlling the throttle amount of conventional such a line pressure, which by the linear solenoid valve 1 ₁ can be sufficiently free of performance pressure the hydraulic servo of the engaging pressure regulating However, it is not necessary to increase the size of the solenoid unit 10, and it is possible to eliminate the need for separately providing a switching valve or the like for turning on / off the feedback pressure. Can be miniaturized.

  Further, the feedback pressure introducing oil passage can be constituted by an in-sleeve oil passage 22B formed in the sleeve portion 22 fitted to the first spool 21 and a feedback input port 21e formed in the first spool 21. Therefore, for example, it is not necessary to provide an oil passage for guiding the feedback pressure to the feedback oil chamber in the valve body 99 of the hydraulic control device, and the hydraulic control device can be downsized. Further, for example, the oil in the first three portions can be obtained by a simple process by simply forming two oil holes 22a and 22c in the sleeve portion 22 and forming a groove 22b in the outer peripheral portion for communicating the two oil holes 22a and 22c. The path 22B can be formed, and the feedback input port 21e can be formed by a simple process by simply drilling a hole at the corresponding position of the first spool 21, that is, the feedback pressure is introduced by a simple process. It is possible to configure an oil passage for this purpose.

Furthermore, the linear solenoid valve 1 _1, since the normally closed type, the power consumption when outputting the maximum output pressure P2 can be reduced from A2 to A1, for example, maintain the engagement state of the frictional engagement elements This can improve the energy efficiency for hydraulic control during the operation, and can improve the fuel efficiency of the vehicle.

<Second Embodiment>
Next, a linear solenoid valve 12 according to a _second embodiment of the present invention will be described with reference to FIGS. FIG. 3 is a cross-sectional view showing a normally open type linear solenoid valve according to the second embodiment, and FIG. 4 is a diagram showing a relationship between current and output hydraulic pressure in the linear solenoid valve according to the second embodiment. .

The linear solenoid valve 12 according to the _second embodiment is a partial modification of the linear solenoid valve 11 according to the _first embodiment. Parts having the same functions are denoted by the same reference numerals, and description thereof is omitted. Further, in FIG. 3, the linear solenoid valve 1 ₂ only shows, although not shown in the valve body 99, and is used being installed in the valve body 99 as in FIG.

The linear solenoid valve 12 according to the _second embodiment is configured by a normally open type as compared with the normally closed type linear solenoid valve 11 according to the _first embodiment, and has an end. The positional relationship is reversed with respect to the direction of movement of the first spool 21 (vertical direction in the figure) while leaving only the positions of the cap 23, the first spring 24, and the drain port Pex3. That is, the washer 25 fixed to the small-diameter land portion 21c of the first spool 21 is in contact with the end portion 19b of the plug 19, and is in contact with the first spring 24 in the hole portion 21h of the large-diameter land portion 21a on the opposite side. is arranged, and also within the valve unit 30 ₂ is reversed. The large-diameter land portion 21b is formed so as to open and communicate with the input port Pin and the output port Pout at the maximum when the large-diameter land portion 21b is in the upper position in the drawing. When the position is moved (stroked), the opening amount of the input port Pin and the output port Pout is gradually reduced, that is, is closed.

The linear solenoid valve 1 ₂ configured as described above, state power supplied to the terminal 14 is zero, i.e. In the de-energized, the plunger 11 is not a stroke drive, the first spring Due to the urging force of 24, the first spool 21, the plug 19, and the plunger 11 are positioned on the upper side in the drawing. Then, the line pressure supplied to the input port Pin is communicated with the output port Pout substantially as it is, and the output hydraulic pressure (hydraulic servo supply hydraulic pressure) becomes the hydraulic pressure P2 as shown in FIG.

  At this time, the output hydraulic pressure acting on the hydraulic oil chamber 33 via the oil passage 21d is larger than the urging force of the second spring 32, and the position of the second spool 31 is on the upper side in the figure, and the second spool 31 The first land portion 31 a closes the feedback input port 21 a of the first spool 21. As a result, the output hydraulic pressure led to the feedback input port 21e of the first spool 21 via the in-sleeve oil passage 22B is cut off, that is, no feedback pressure is supplied to the feedback oil chamber 27. Further, the second land portion 31b of the second spool 31 opens the drain port 21f of the first spool 21, and the feedback oil chamber 27 communicates with the drain port Pex2 via the oil hole 21g, the oil passage 34, and the drain port 21f. In other words, the feedback pressure supplied in the feedback oil chamber 27 is drained to zero.

  Next, when supply of power to the solenoid unit 10 is started, the first spool 21 is moved downward in the figure against the urging force of the first spring 24 by the plunger 11. Then, the opening amount of the input port Pin and the output port Pout is reduced by the movement of the large-diameter land portion 21b, and the line pressure of the input port Pin is reduced based on the opening amount, and the output port Pout The output hydraulic pressure is further reduced.

In this case, if the power supplied is less than the predetermined current value Ax shown in FIG. 4, the feedback pressure on the first spool 21 by the internal valve portion 30 ₂ does not act, with respect to the first spool 21 Is a state where only the driving force of the plunger 11 and the urging force of the first spring act. As a result, the relationship between the output hydraulic pressure and the electric power is a proportional relationship with a steep slope as indicated by X2 _{N / O} (feedback OFF state) in FIG. Therefore, fine control of the output hydraulic pressure supplied to the hydraulic servo (not shown) is unnecessary, for example, in a high hydraulic pressure region from the engagement hydraulic pressure P2 to the engagement hydraulic pressure P1, and the output hydraulic pressure is rapidly increased / decreased. be able to.

  Subsequently, when the electric power supplied to the solenoid unit 10 becomes equal to or greater than the predetermined current value Ax shown in FIG. 4, the output hydraulic pressure decreases, and the urging force of the second spring 32 is hydraulic oil via the oil passage 21d. The output hydraulic pressure acting on the chamber 33 becomes larger, the relative position of the second spool 31 with respect to the first spool 21 is the lower side in the figure, and the first land portion 31a of the second spool 31 is in the first spool 21. The feedback input port 21a is opened, and the second land portion 31b closes the drain port 21f. As a result, the output oil pressure of the output port Pout is guided to the feedback input port 21e of the first spool 21 via the oil passage 22B in the sleeve, and further to the feedback oil chamber 27 via the oil passage 34 and the oil hole 21g. .

In this state, the driving force of the plunger 11, the biasing force of the first spring, and the feedback force of the feedback oil chamber act on the first spool 21, and respond to the increase in the current supplied to the solenoid unit 10. Since the output hydraulic pressure decreases and a feedback pressure proportional to the output hydraulic pressure acts, the relationship between the output hydraulic pressure and the electric power is the above X1 as indicated by X1 _{N / O} (feedback ON state) in FIG. It becomes a direct proportional relationship with a gentler slope than _{N / O.} Accordingly, it is necessary to finely control the output hydraulic pressure supplied to a hydraulic servo (not shown), for example, in a low hydraulic pressure region lower than the engagement hydraulic pressure P1 where the friction engagement element is completely engaged, Engagement control such as the slip state of the joint element can be performed with high accuracy.

As described above, in the present linear solenoid valve 1 _2, it can be performed by the internal valve portion 30 ₂ by automatic switching based on the output hydraulic feedback pressure on and off, conventional in FIG As shown in the relationship Y _{N / O} between the output hydraulic pressure and the current, the current A2 required to make the output hydraulic pressure zero can be reduced to the current A1. That is, the maximum driving force performance of the plunger 11 of the solenoid unit 10 can be reduced from the driving force corresponding to the current A2 to the driving force corresponding to the current A1, and accordingly, the coil assembly 17 of the solenoid unit 10 and the like. The size can be made compact.

Thus, for example, without providing a control valve for controlling the throttle amount of conventional such a line pressure, which by the linear solenoid valve 1 ₂ can be sufficiently free of performance pressure the hydraulic servo of the engaging pressure regulating However, it is not necessary to increase the size of the solenoid unit 10, and it is possible to eliminate the need for separately providing a switching valve or the like for turning on / off the feedback pressure. Can be miniaturized.

Further, the linear solenoid valve 1 _2, since the normally open type, the power consumption when the output hydraulic pressure to 0 (non-output) can be reduced from A2 to A1, for example, a released state of the friction engagement elements The energy efficiency of the hydraulic control when maintaining the above can be improved, and the fuel efficiency of the vehicle can be improved.

<Third Embodiment>
Next, a linear solenoid valve 13 according to a _third embodiment of the present invention will be described with reference to FIG. FIG. 5 is a sectional view showing a normally closed type linear solenoid valve according to a third embodiment.

The linear solenoid valve 13 according to the _third embodiment is a partial modification of the linear solenoid valve 11 according to the _first embodiment. Parts having the same functions are denoted by the same reference numerals, and description thereof is omitted. Further, in FIG. 5, the linear solenoid valve 1 ₃ only shows, although not shown in the valve body 99, and is used being installed in the valve body 99 as in FIG.

Linear solenoid valve 1 ₃ according to the third embodiment is different from the linear solenoid valve 1 ₁ according to the first embodiment, by changing the configuration of the internal valve portion 30 _3, the feedback pressure introduction oil The passage is changed from an oil passage 22B in the sleeve (see FIG. 1) to an oil passage in the inner sleeve (feedback pressure introduction oil passage, second oil passage in the sleeve) 39B. That is, the internal valve unit 30 _3, inner sleeve member that is fitted and fixed to the inner peripheral portion of the hollow hole 21A has a (second sleeve member) 39, the inner peripheral surface 39A of the internal sleeve member 39 The second spool 31 is slidably inserted. The internal sleeve member 39 includes a feedback input port 39b, oil holes 39c communicating with the oil holes 21g, and drain ports 39d, each of which is an oil hole formed in a direction perpendicular to the longitudinal direction. In addition, an oil passage 39a that connects the feedback input port 39b and the hydraulic oil chamber 33 is formed. That is, the feedback pressure introduction oil passage that guides the output hydraulic pressure led to the hydraulic oil chamber 33 to the feedback oil chamber 27 in a state where the second spool 31 is located in the upper portion in the figure by the oil passage 39a and the feedback input port 39b. It is composed.

  Thus, when the output hydraulic pressure is less than the hydraulic pressure P1, the first land portion 31a of the second spool 31 opens the feedback input port 39b, and the output hydraulic pressure led to the hydraulic oil chamber 33 is It is led to the feedback oil chamber 27 through 39a, the feedback input port 39b, the oil passage 34, the oil hole 39c and the oil hole 21g. When the output hydraulic pressure is equal to or higher than the hydraulic pressure P1, the first land portion 31a of the second spool 31 closes the feedback input port 39b, and the second land portion 31b opens the drain port 39d. The oil pressure in the feedback oil chamber 27 is drained through the oil hole 21g, the oil hole 39c, the oil passage 34, the drain ports 39d, 21f, and Pex2.

  In this way, the feedback pressure introduction oil passage is formed in the inner sleeve member 39, and is formed of the inner sleeve oil passage 39B that allows the hydraulic oil chamber 33 and the feedback oil chamber 22 to communicate with each other. It is unnecessary to provide an oil passage for guiding the feedback pressure to the feedback oil chamber 27, and the hydraulic control device can be downsized. Further, for example, the inner sleeve member 39 is processed to form an inner sleeve oil passage 39B, and the inner sleeve member 39 is connected to the inner peripheral side of the hollow hole 21A of the first spool 21 and the outer peripheral side of the second spool 31. It is possible to configure the feedback pressure introducing oil passage only by assembling so as to be interposed between them, that is, to simplify the assembly process.

  Since other configurations, operations, and effects are the same as those in the first embodiment, the description thereof is omitted.

<Fourth embodiment>
Next, a linear solenoid valve 14 according to a _fourth embodiment of the present invention will be described with reference to FIG. FIG. 6 is a sectional view showing a normally open type linear solenoid valve according to a fourth embodiment.

In addition, since the linear solenoid valve 14 according to the _fourth embodiment is a partial modification of the linear solenoid valve 12 according to the _second embodiment, mainly the changed portion will be described. Parts having the same functions are denoted by the same reference numerals, and description thereof is omitted. Further, in FIG. 6, the linear solenoid valve 1 ₄ show only, although not shown in the valve body 99, and is used being installed in the valve body 99 as in FIG.

The linear solenoid valve 14 according to the _fourth embodiment includes an internal valve portion 30 ₂ (see FIG. 3) in the linear solenoid valve 12 according to the _second embodiment described above, and the third embodiment. those configured similarly to the inner valve portion 30 3 of the linear solenoid valve 1 _{3 (see} FIG. 5) according to. In other words, the linear solenoid valve 14 according to the _fourth embodiment is configured as a normally open type as compared with the normally closed type linear solenoid valve 13 according to the _third embodiment. Yes, with the positions of the end cap 23, the first spring 24, and the drain port Pex3 remaining as they are, the positional relationship is reversed with respect to the moving direction (vertical direction in the drawing) of the first spool 21.

  Thus, when the output hydraulic pressure is less than the hydraulic pressure P1, the first land portion 31a of the second spool 31 closes the feedback input port 39b, and the second land portion 31b opens the drain port 39d. The oil pressure in the feedback oil chamber 27 is drained through the oil hole 21g, the oil hole 39c, the oil passage 34, the drain ports 39d, 21f, and Pex2. When the output oil pressure is equal to or higher than the oil pressure P1, the first land portion 31a of the second spool 31 opens the feedback input port 39b, and the output oil pressure guided to the hydraulic oil chamber 33 is the oil passage. It is led to the feedback oil chamber 27 through 39a, the feedback input port 39b, the oil passage 34, the oil hole 39c, and the oil hole 21g.

  Since other configurations, functions, and effects are the same as those in the second embodiment, description thereof is omitted.

  In the embodiment described above, the linear solenoid valve in which the solenoid unit 10 linearly drives the plunger 11 has been described as an example of the solenoid valve. However, the present invention is not limited thereto, and any solenoid valve can be used. In particular, the configuration of the solenoid unit 10 is not limited to the configuration of the present embodiment.

  In the above embodiment, the solenoid valve is used as a hydraulic control device for an automatic transmission to regulate the hydraulic pressure of the hydraulic servo of the friction engagement element. The solenoid valve may be used in any device as long as the solenoid valve is used in a device that requires the above.

Sectional drawing which shows the normally closed type linear solenoid valve which concerns on 1st Embodiment. The figure which shows the relationship between the electric current and output hydraulic pressure in the linear solenoid valve which concerns on 1st Embodiment. Sectional drawing which shows the normally open type linear solenoid valve which concerns on 2nd Embodiment. The figure which shows the relationship between the electric current and output hydraulic pressure in the linear solenoid valve which concerns on 2nd Embodiment. Sectional drawing which shows the normally closed type linear solenoid valve which concerns on 3rd Embodiment. Sectional drawing which shows the normally open type linear solenoid valve which concerns on 4th Embodiment.

Explanation of symbols

1 Solenoid valve (Linear solenoid valve)
10 Solenoid part 11 Plunger 20 Valve part 21 First spool 21A Hollow part (hollow hole) of the first spool
21d Introducing oil passage 21e Feedback pressure introducing oil passage, feedback input port 22 First sleeve member (sleeve portion)
22B Feedback pressure introducing oil passage, first sleeve oil passage (sleeve oil passage)
24 First urging means (first spring)
27 Feedback oil chamber 31 Second spool 32 Second urging means (second spring)
33 Hydraulic oil chamber 39 Second sleeve member (inner sleeve member)
39B Feedback pressure introduction oil passage, second sleeve oil passage (inner sleeve oil passage)
Pin input port Pout Output port Pex2 Drain port P1 Predetermined pressure

Claims (6)

A solenoid portion that drives the plunger in accordance with the supplied electric power, and an input port to which input hydraulic pressure is input by moving the first spool against the urging force of the first urging means by the driving force of the plunger A valve portion having a feedback oil chamber that adjusts the opening amount between the output port and the output hydraulic pressure output from the output port in a direction to reduce the opening amount.
A feedback pressure introduction oil passage capable of introducing the output hydraulic pressure into the feedback oil chamber;
A second spool movably disposed in a hollow portion formed in the first spool;
A second biasing means for receiving a reaction force by the first spool and biasing the second spool toward one side in the moving direction;
A hydraulic oil chamber in which the input hydraulic pressure opposes the second spool with respect to the biasing force of the second biasing means;
An introduction oil passage that is drilled in the first spool and communicates the output port with the hydraulic oil chamber to introduce the output hydraulic pressure into the hydraulic oil chamber;
A drain port capable of discharging the oil in the feedback oil chamber,
The second spool shuts off the feedback oil chamber and the drain port when the output oil pressure acting on the hydraulic oil chamber via the introduction oil passage is less than a predetermined pressure, and the feedback oil chamber The feedback oil chamber and the feedback pressure introduction oil passage when the output oil pressure acting on the hydraulic oil chamber via the introduction oil passage is greater than or equal to a predetermined pressure is a position that communicates with the feedback pressure introduction oil passage. And the position where the feedback oil chamber communicates with the drain port,
A solenoid valve characterized by that. The feedback pressure introduction oil passage is formed in a first sleeve oil passage formed in a first sleeve member fitted to the first spool, and is formed in the first spool and communicates with the first sleeve oil passage. A feedback input port,
The solenoid valve according to claim 1. A second sleeve member interposed between the inner periphery of the hollow portion of the first spool and the outer periphery of the second spool;
The feedback pressure introduction oil passage is formed in the second sleeve member, and includes a second sleeve oil passage that can communicate the hydraulic oil chamber and the feedback oil chamber.
The solenoid valve according to claim 1. When the solenoid portion is in a non-energized state, the input port and the output port are blocked by the first spool by the biasing force of the first biasing means.
The solenoid valve according to any one of claims 1 to 3. When the solenoid portion is in a non-energized state, the input port and the output port are communicated with each other by the first spool by the biasing force of the first biasing means.
The solenoid valve according to any one of claims 1 to 3. Used in a hydraulic control device of an automatic transmission capable of supplying an output hydraulic pressure output from the output port to a hydraulic servo of a friction engagement element;
The solenoid valve according to any one of claims 1 to 5.

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