KR101016189B1 - Solenoid valve for transmission - Google Patents

Abstract

PURPOSE: A solenoid valve for a transmission is provided to secure a magnetic force strong enough for controlling a high pressure and high flow rate. CONSTITUTION: A solenoid valve for a transmission comprises a solenoid part and a valve part driven by the operation of the solenoid part. The solenoid part comprises a core(220), a yoke(270), and a plunger(240). The yoke is separated from the core and has a first width, a second width, and a third width on a longitudinal plane successively toward the core, wherein the first width is greater than the second width and the second width is greater than the third width. The plunger operates the valve part by being reciprocated with the core and the yoke.

Description

Solenoid Valve for Transmission {SOLENOID VALVE FOR TRANSMISSION}

The present invention relates to a solenoid valve for a transmission, and more particularly, to a solenoid valve for a transmission capable of directly controlling a clutch of an automatic transmission.

In general, internal combustion engines for automobiles require stronger torque and lower rotational speed when they start running, and higher rotational speeds than torque are needed to make the driving speed faster. Accordingly, the transmission is to reduce the rotational speed and increase the torque at the same time when starting using the gear to maintain the constant rotation of the engine, and to increase the rotational speed in order to increase the running speed. Such a transmission includes a manual transmission in which a person directly manipulates a clutch and an automatic transmission that directly performs a shift according to speed by hydraulic pressure.

On the other hand, in the conventional automatic transmission, solenoid valves of an indirect control type that indirectly controls the clutch by a low reduced control pressure have been mainly used. This solenoid valve of the indirect control type requires a complicated hydraulic circuit for the control of high flow rate and high clutch pressure to control the clutch. However, the solenoid valve adopting the conventional indirect control method has a disadvantage in that the hydraulic circuit becomes more complicated as the speed of the transmission increases, thereby increasing the size of the entire apparatus and increasing the manufacturing cost thereof. Accordingly, in recent years, research and development of a solenoid valve capable of simplifying the hydraulic circuit and miniaturizing the size of the entire apparatus and reducing the manufacturing cost thereof have been conducted.

It is an object of the present invention to provide a solenoid valve for a transmission capable of securing a sufficient magnetic force for controlling high pressure and high flow rate.

In addition, another object of the present invention is to provide a solenoid valve for a transmission that can increase the overlap.

In order to achieve the above object, the present invention provides a solenoid valve for a transmission comprising a solenoid portion and a valve portion operated by the operation of the solenoid portion, wherein the solenoid portion is spaced apart from the core and the core by a predetermined distance, and parallel to the longitudinal direction. A yoke having a first width, a second width, and a third width different from each other in a direction proximate to the core with respect to one surface thereof, and a plunger reciprocating by the core and the yoke to operate the valve portion. Provided is a solenoid valve for a transmission. The first width is greater than the second width, and the second width is greater than the third width. The yoke has a first surface and a ninth surface forming the first width, a fourth surface and a ninth surface forming the second width, and the third width based on a cross section in the longitudinal direction. A sixth and a ninth face, wherein a third face is formed between the first face and the fourth face, and a third face is a vertical face and an inclined face is formed between the fourth face and the sixth face. A fifth surface is formed, and at the end of the sixth surface, a seventh surface which is an inclined surface and an eighth surface which is connected to the end of the ninth surface and a vertical surface are formed.

It is preferable that the predetermined interval between the yoke and the core is 1.5mm to 2.5mm. The valve portion includes a hollow holder having one or more chambers and ports, and a spool in which the one or more annular grooves are formed and vertically reciprocates in the holder by the solenoid portion. The holder has a discharge chamber, a control chamber, a supply chamber and a feedback chamber 112 sequentially formed in the direction of the solenoid portion, and the spool has a width greater than that of the first annular groove and the first annular groove in the direction of the solenoid portion. The narrow second annular groove may be formed sequentially. However, the present invention is not limited thereto, and the holder is sequentially formed with a feedback chamber 112 in the direction of the solenoid portion, a supply chamber, a control chamber and a discharge chamber, and the spool has a first direction in the direction of the solenoid portion. The annular groove and the second annular groove wider than the first annular groove may be sequentially formed.

The present invention also provides a feedback flow path formed in the feedback chamber 112 of the holder, a supply port formed at one end of the supply chamber of the holder, a control flow path formed in the control chamber of the holder, and formed at one end of the control chamber of the holder. And a discharge port formed at one end of the discharge chamber of the holder. In this case, the feedback flow path is connected to the control flow path, the feedback flow path is 0.5mm to 1.5mm in diameter, it is effective that the thickness is 1.5mm to 2.5mm.

In addition, the present invention may further include a filter mounted to at least one of the supply port and the control port. At this time, a filter mounting groove is formed in at least one of the supply port and the control port, and mounting jaws mounted on the filter mounting groove are formed at ends of the filter, respectively.

In addition, the present invention may further include a guide provided to surround the outer periphery of the core and the yoke so that the core and the yoke are integrated. In this case, steps are formed on the outer periphery of the core and the yoke, respectively, and the guide is provided on the steps.

The present invention may provide a solenoid valve for a transmission having a plunger and a core and a yoke having three widths separated from the core by 1.5 mm to 2.5 mm to secure sufficient magnetic force for controlling high pressure and high flow rate.

In addition, the present invention can provide a solenoid valve for a transmission that can form a feedback flow path has a diameter of 0.5mm to 1.5mm and a thickness of 1.5mm to 2.5mm to increase the overlap.

In addition, the present invention may be provided with a solenoid valve for a transmission that can prevent the deformation of the transmission solenoid valve and improve the durability even if an external force is applied by having a guide integrally configured with the core and the yoke.

In addition, the present invention can provide a solenoid valve for a transmission resistant to foreign matter by mounting a filter in at least one of the supply port and the control port of the holder.

1 is a cross-sectional view of a solenoid valve for a transmission according to a first embodiment of the present invention.
FIG. 2 is an enlarged cross-sectional view of region A of FIG. 1. FIG.
3 is a cross-sectional view of a solenoid valve for a transmission in accordance with a modification of the first embodiment of the present invention.
4 is a side view of a solenoid valve holder for a transmission according to a modification of the first embodiment of the present invention.
5 is a cross-sectional view of a yoke of a solenoid valve for a transmission according to a first embodiment of the present invention.
6 is a cross-sectional view of a core and a yoke of a solenoid valve for a transmission in accordance with a modification of the first embodiment of the present invention.
7 is a cross-sectional view showing the flow of pressure during operation of the solenoid valve for a transmission according to the first embodiment of the present invention.
8 is a cross-sectional view of a solenoid valve for a transmission in accordance with a second embodiment of the present invention.
FIG. 9 is an enlarged cross-sectional view of region B of FIG. 8;
10 is an output waveform diagram measured during operation of a transmission solenoid valve and a transmission solenoid valve according to the related art according to a second embodiment of the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

It will be apparent to those skilled in the art that the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, It is provided to let you know. Like reference numerals in the drawings refer to like elements.

1 is a cross-sectional view of a solenoid valve for a transmission according to a first embodiment of the present invention, Figure 2 is an enlarged cross-sectional view showing a region A of FIG. 3 is a cross-sectional view of a solenoid valve for a transmission according to a modification of the first embodiment of the present invention, and FIG. 4 is a side view of a solenoid valve holder for a transmission according to a modification of the first embodiment of the present invention. 5 is a cross-sectional view of a yoke of a solenoid valve for a transmission according to a first embodiment of the present invention, Figure 6 is a cross-sectional view of the core and the yoke of a solenoid valve for a transmission according to a modification of the first embodiment of the present invention. 7 is a cross-sectional view showing the pressure flow during operation of the solenoid valve for a transmission according to the first embodiment of the present invention.

As shown in FIG. 1, the transmission solenoid valve according to the first embodiment of the present invention includes a valve part 100 and a solenoid part 200 for driving the valve part 100.

The valve unit 100 is mounted on a valve body (not shown) having a plurality of flow paths so as to be supplied to a clutch (not shown) while applying a predetermined control pressure to a fluid supplied from an external hydraulic supply source. The holder 110, the spool 120 is provided to be movable inside the holder 110, and the spring 130 and the pressure control screw 140 provided on the upper portion of the spool 120, respectively.

The holder 110 has a hollow shape in which the movement of the spool 120 is guided therein, and the discharge chamber 117a, the control chamber 113a, and the supply chamber 115a from the upper side to the lower side in the spool 120. ), The feedback chamber 112 is formed sequentially. Here, the discharge port 117b is formed at one end of the discharge chamber 117a, and the residual pressure is partially discharged through the discharge port 117b. One end of the control chamber 113a is formed with a control port 113b connected to the clutch (not shown) side of the transmission to adjust the clutch pressure. In addition, one end of the supply chamber 115a is provided with a supply port 115b that is connected to an external hydraulic supply source, and one end of the feedback chamber 112 is mounted on the valve body (the dashed line on the left side of FIG. 4). An opening 118 that is closed by the mounting surface of is formed. In addition, a first auxiliary discharge chamber 117a, which is a space in which oil remaining on the outer circumferential surface of the spool 120 temporarily remains, is formed at the top of the holder 110, and one end of the first auxiliary discharge chamber 111a is formed at the first end of the first auxiliary discharge chamber 111a. A first auxiliary discharge port 114a is formed to discharge the oil remaining in the auxiliary discharge chamber 111a to freely move the spool 120. In addition, a second auxiliary discharge chamber 111b is formed at a lower end of the holder 110, and at one end thereof, a second discharge of oil or other foreign matters buried on the outer circumferential surface of the spool 120 to the outside and also removes residual pressure. Auxiliary discharge port 114b is formed. Meanwhile, as illustrated in FIG. 4, a flow path for communicating the feedback chamber 112 and the control chamber 113a is formed at one outer circumferential surface of the holder 110. The flow path includes a feedback flow path 119 formed in the feedback chamber 112 and a control flow path 116 formed in the control chamber 113a. The solenoid valve according to the first embodiment of the present invention includes a valve body (see FIG. 4). When mounted on the right side dotted line part, it is sealed by the mounting surface of the valve body.

Meanwhile, the present invention may further include a filter 150 in at least one of the control port 113b and the supply port 115b of the holder 110, as shown in FIG. 3.

The filter 150 is for filtering foreign substances introduced into the control port 113b and the supply port 115b of the holder 110, and has a plurality of holes in the shape of an annular band. This embodiment illustrates that the first filter 150a is provided at the control port 113b and the second filter 150b is provided at the supply port 115b. In addition, as shown in FIG. 4, the filter mounting grooves R1 and R2 are formed in the control port 113b and the supply port 115b so that the first and second filters 150a and 150b are mounted and fixed. Each is formed. The first and second filters 150a and 150b are provided with mounting jaws bent at predetermined angles at the ends, and the mounting jaws are mounted in the filter mounting grooves R1 and R2. , 150b are mounted on the control port 113b and the supply port 115b to be fixed.

In the uppermost open area of the holder 110, a control pressure applied to the clutch side through the control port 113b is adjusted, and a pressure adjustment screw 140 capable of vertically adjusting is installed. In addition, between the pressure control screw 140 and the spool 120 is provided with a spring 130 for providing an elastic force in the lower direction of the spool 120 and at the same time buffer the spool 120 when moving up and down the spool 120. do.

The spool 120 is installed to be movable inside the hollow holder 110, and one or more annular grooves are formed on the outer circumferential surface thereof. The present embodiment illustrates the first annular groove 121a and the second annular groove 121b narrower than the first annular groove 121a sequentially formed in the direction of the solenoid portion 200 with such an annular groove. And the second annular groove 121b switches the flow of the fluid or opens and closes the supply port 115b, the control port 113b, and the discharge port 117b.

The solenoid part 200 is for operating the valve part 100, the bobbin 210 wound around the coil 220 to move the spool 120 of the valve part 100 up and down, and the outer circumferential surface of the bobbin 210. A case 230 enclosing the casing, a plunger 240 installed to move up and down in the inner diameter portion of the bobbin 210, and a rod 250 fixed to a central portion of the plunger 240 to be in contact with the lower end of the spool 120. And a core 260 disposed at one end of the plunger 240, a yoke 270 disposed at the other end of the plunger 240, and a terminal portion 280 connected to the yoke 270. It also includes a terminal 294 and a fork terminal 296 provided below the terminal portion 280.

The bobbin 210 has a hollow cylindrical shape, and a coil 220 is wound around its outer circumferential surface. A portion of the bobbin 210 is accommodated so that the core 260 and the yoke 270 are spaced apart from each other by a predetermined interval.

The plunger 240 is disposed between the core 260 and the yoke 270 and moves toward the core 260 by a magnetic field generated when power is applied to the coil 220. In this case, the core 260 is formed with a hollow portion of the first core 260 in which magnetic force is concentrated in a portion adjacent to the plunger 240, and one end of the plunger 240 is partially accommodated in the hollow portion of the first core 260. In addition, a second core 260 hollow portion having a diameter smaller than that of the first core 260 hollow portion is formed at an upper end of the hollow part of the first core 260, and an upper end of the rod 250 is formed at the hollow part of the second core 260 hollow part. This is movably accommodated.

The yoke 270 is formed in the hollow portion of the first yoke 270 adjacent to the plunger 240, and the other end of the plunger 240 is partially accommodated in the hollow portion of the first yoke 270. The lower portion of the first hollow portion is formed with a second hollow portion having a smaller diameter than the first hollow portion, the lower end of the rod 250 is accommodated in the second hollow portion to be movable.

As shown in FIG. 2, the yoke 270 is spaced apart from the core 260 by a predetermined interval. At this time, the core 260 and the yoke 270 is spaced at intervals of 1.5mm to 2.5mm, the magnetic force is reduced when the distance between the core 260 and the yoke 270 is larger than this, and when the power is off when small This will affect the return of the plunger 240.

In addition, the yoke 270, as illustrated in Figure 5, the core 260 and the region close the first to ninth surface have a (S ₁ to S _9), the first surface (S ₁₎ and a second side The first angle θ ₁ is formed at the boundary of S ₂ . In addition, a second angle θ ₂ is formed at the boundary between the second surface S ₂ and the third surface S ₃ , and is formed at the boundary between the third surface S ₃ and the fourth surface S ₄ . Three angles θ ₃ are formed. Further, a fourth angle θ ₄ is formed at the boundary between the fourth surface S ₄ and the fifth surface S ₅ , and is formed at the boundary between the fifth surface S ₅ and the sixth surface S ₆ . Five angles θ ₅ are formed. Boundary of the sixth side (S ₆ ) and the seventh side (S ₇ ), boundary of the seventh side (S ₇ ) and the eighth side (S ₈ ), and the eighth side (S ₈ ) and the ninth side (S ₉₎ The sixth to eighth angles θ ₆ , θ ₇ , and θ ₈ are formed at the boundaries of). At this time, the first surface S ₁ and the fourth surface S ₄ , the sixth surface S ₆ , and the ninth surface S ₉ are parallel to each other, and the third surface S ₃ and the eighth surface ( S ₈ ) are parallel to each other. Further, the first angle θ ₁ , the second angle θ ₂ , the fourth angle θ ₄ , the sixth angle θ ₆ , the seventh angle θ ₇ , and the eighth angle θ ₈ are Bent in a direction different from the third angle θ ₃ and the fifth angle θ ₅ , and the first angle θ ₁ , the second angle θ ₂ , and the fourth angle θ ₄ to the seventh angle S ₇ is formed at an obtuse angle, and the third angle θ ₃ and the eighth angle θ ₈ are formed at right angles. Also, this way, the yoke 270 has a first surface (S ₁₎ and a first surface a second surface extending from (S ₁₎ an inclined to a side bend (S ₂₎ and a second surface (S ₂₎ extension is a vertically bent to one side and the third surface in (S ₃₎ and a third surface (S ₃₎ extend from the fourth surface (S ₄₎ and a fourth surface (S ₄₎ bent side to the other extending from the the surface of inclined to one side and bending of claim 5 extending from the (S ₅₎ and the fifth surface (S ₅₎ a sixth surface (S ₆₎ and a sixth surface (S ₆₎ bent side to the other extending from the one side inclining the bending seventh surface extending in the (S ₇₎ and the seventh surface (S ₇₎ extended is perpendicularly bent to one side in the eighth surface (S ₈₎ and the eighth surface (S ₈₎ doedoe bent to one side It includes a ninth surface (S ₉ ) formed in parallel so that the first surface (S ₁ ) and the partial region overlap. With this structure, the first width P ₁ between the first surface S ₁ and the ninth surface S ₉ , and the product between the fourth surface S ₄ and the ninth surface S ₉ . The second width P ₁ and the third width P ₃ between the sixth surface S ₆ and the ninth surface S ₉ are different from each other. In this case, the first width P ₁ , the second width P ₂ , and the third width P ₃ are each of the first width P ₁ > the second width P ₂ > the third width P ₃ . Have a relationship.

The yoke 270 according to the present embodiment can secure a sufficient magnetic force for controlling the high pressure and the high flow rate by such a shape, and the overlap (inlet / outlet) is secured by securing a long stroke. ) Can be increased.

Meanwhile, the first and second bushings 292b are spaced apart from each other and separately pressed into the second core hollow portion of the core 260 and the second yoke hollow portion of the yoke 270. The first and second bushings 292b eliminate interference based on the degree of processing of the yoke 270, the core 260, and the plunger 240, thereby smoothing up and down reciprocation of the plunger 240 and the plunger 240. Minimize left and right flow and tilt. And the positioning member 290 is provided in the 2nd core hollow part of the core 260. As shown in FIG.

Meanwhile, in the present invention, the guide 215 may be added to integrate the core 260 and the yoke 270.

The guide 215 is formed in a hollow cylindrical shape so as to surround a portion of the core 260 and the yoke 270 together. In addition, as shown in FIG. 6 to mount the guide 215, a stepped portion for mounting the guide 215 is formed at the outer circumferences of the core 260 and the yoke 270.

As such, when the guide 215 is provided, the core 260 and the yoke 270 may be integrated to prevent deformation of the solenoid valve for transmission and improve durability when an external force is applied.

The rod 250 is fixed to the center of the plunger 240, and the upper end of the rod 250 is in contact with the lower end of the spool 120. The rod 250 moves while passing through the hollow portion of the second core 260 of the core 260 and the hollow portion of the second yoke 270 of the yoke 270.

In the transmission solenoid valve according to the first embodiment of the present invention having the above-described structure, as shown in FIG. 7, first, when power is applied to the coil 220 side, the core 260 and the yoke 270 and The plunger 240 is magnetized, whereby the plunger 240 moves to the core 260 side. At this time, the rod 250 fixed to the core 260 also moves together with the plunger 240. In addition, during the initial movement of the rod 250, the rise of the rod 250 and the plunger 240 proceeds gradually up to a specific current value so that the control pressure through the control port 113b is not applied to the clutch side. That is, since the external force is not applied except for the magnetic force while the rod 250 moves upward, no excessive control pressure is applied to the clutch side through the control chamber 113a and the control port 113b. Therefore, leakage of hydraulic pressure can be minimized. Thereafter, as the magnetic force increases while exceeding the specific current value, the rod 250 and the plunger 240 rise to open the supply port, thereby increasing the control pressure in the control chamber 113a. The elevated control pressure applies a part of the fluid to the feedback chamber 112 through the feedback flow path 119, and thus, by the feedback pressure in the feedback chamber 112 and the spring 130 force of the spring 130. Downward force is applied to the spool 120 side. In this case, upward force is applied to the spool 120 side by the magnetic force. That is, when the spool 120 moves upward, the pressure is balanced through the upward force and the downward force, and linear pressure control of the control pressure is achieved.

As described above, the solenoid valve for a transmission according to the present embodiment has a plunger and a core and a yoke having three widths separated from the core and the core by 1.5 mm to 2.5 mm to secure sufficient magnetic force for controlling high pressure and high flow rate. have.

Next, a solenoid valve for a transmission according to a second embodiment of the present invention will be described with reference to the drawings. Descriptions overlapping with the description of the solenoid valve for a transmission according to the first embodiment of the present invention described above will be omitted or briefly described.

8 is a cross-sectional view of a solenoid valve for a transmission according to a second exemplary embodiment of the present invention, and FIG. 9 is an enlarged cross-sectional view of region B of FIG. 8. 10 is an output waveform diagram measured during operation of a transmission solenoid valve and a transmission solenoid valve according to the related art according to a second embodiment of the present invention.

As shown in FIG. 8, the transmission solenoid valve according to the second embodiment of the present invention includes a valve part 100 and a solenoid part 200 for driving the valve part 100. At this time, the solenoid portion 200 of the transmission solenoid valve according to the second embodiment of the present invention is the same as the transmission solenoid valve according to the first embodiment of the present invention described above will be omitted. In addition, according to the present invention, since the solenoid part 200 may be commonly used in the production of the solenoid valve for the NH type and the NL type transmission according to each of the first and second embodiments of the present invention, a separate production line may be used. It may not be equipped to reduce the production cost. In addition, it is possible to improve the performance stabilization of the solenoid valve for the transmission produced by using the same component (solenoid portion).

The valve unit 100 according to the present embodiment is mounted on a valve body (not shown) having a plurality of flow paths so as to be supplied to a clutch (not shown) while applying a predetermined control pressure to a fluid supplied from an external hydraulic supply source. To this end, the hollow holder 110, the spool 120 is provided to be movable inside the holder 110, and includes a spring 130 and a pressure adjusting screw provided on the upper portion of the spool 120, respectively do.

The spool 120 is installed to be movable inside the hollow holder 110, and one or more annular grooves are formed on the outer circumferential surface thereof. This embodiment illustrates the first annular groove 121a and the second annular groove 121b wider than the first annular groove 121a as the annular groove.

The holder 110 has a hollow shape in which the movement of the spool 120 is guided therein, and the feedback chamber 112, the supply chamber 115a, and the control chamber 113a from the top to the bottom of the spool 120. ), The discharge chamber 117a is sequentially formed. Here, one end of the feedback chamber 112, the supply chamber 115a, the control chamber 113a, and the discharge chamber 117a includes an opening 118, a supply port 115b, a control port 113b, and an exhaust port 117b. Are respectively formed, and a first auxiliary discharge chamber 111a and a first auxiliary discharge port 114a formed at one end thereof are formed at an upper portion of the feedback chamber 112. In addition, a second auxiliary discharge chamber 111b and a second auxiliary discharge port 114b formed at one end thereof are formed below the discharge chamber 117a. In this case, as shown in FIG. 9, the feedback flow path 119 has a diameter R of 0.5 mm to 1.5 mm and a thickness T of 1.5 mm to 2.5 mm to increase the overlap. can do.

As shown in FIG. 10, the transmission solenoid valve according to the present embodiment having such a structure has a higher response speed than the conventional solenoid valve for transmission, and a transmission capable of removing the effect of undershoot. A solenoid valve can be provided. In addition, it is possible to prevent the instantaneous change of the clutch force to prevent the shift shock, it is possible to improve the durability of the automatic transmission.

As described above, the solenoid valve for a transmission according to the present embodiment has a plunger and a core and a yoke having three widths separated from the core and the core by 1.5 mm to 2.5 mm to secure sufficient magnetic force for controlling high pressure and high flow rate. The feedback passage 119 may have a diameter of 0.5 mm to 1.5 mm and have a thickness of 1.5 mm to 2.5 mm, that is, a length to increase the overlap.

Although described above with reference to the drawings and embodiments, those skilled in the art can be variously modified and changed within the scope of the invention without departing from the spirit of the invention described in the claims below. I can understand.

100: valve portion 110: holder
111a: first auxiliary discharge chamber 111b: second auxiliary discharge chamber
112: feedback chamber 112 113a: control chamber
113b: control port 114a: first auxiliary exhaust port
114b: second auxiliary discharge port 115a: supply chamber
115b: supply port 117a: discharge chamber
117b: discharge port 118: opening
119: feedback euro 120: spool
121a: first annular groove 121b: second annular groove
130: spring 140: pressure adjustment screw
150: filter 150a: first filter
150b: second filter 200: solenoid portion
210: bobbin 215: guide
220: coil 230: case
240: plunger 250: rod
260: core 270: yoke
280: terminal portion 290: positioning member
292a: first bushing 292b: second bushing
294: terminal 296: fork terminal
R1, R2: Filter mounting groove

Claims (13)

In the solenoid valve for a transmission comprising a solenoid portion and a valve portion operated by the operation of the solenoid portion,
The solenoid portion core,
A yoke spaced apart from the core at a predetermined interval and sequentially having a first width, a second width, and a third width different from each other in a direction close to the core with respect to a plane parallel to a longitudinal direction;
And a plunger reciprocating by the core and the yoke to operate the valve unit. The method according to claim 1,
The first width is greater than the second width, the second width is greater than the third width, the solenoid valve for a transmission. The method according to claim 2,
The yoke is based on the cross section in the longitudinal direction,
First and ninth surfaces defining the first width,
Fourth and ninth surfaces defining the second width, and
A sixth side and a ninth side forming the third width,
Between the first surface and the fourth surface is formed a second surface and a third surface perpendicular to the inclined surface,
Between the fourth surface and the sixth surface is formed a fifth surface which is an inclined surface,
The solenoid valve for a transmission, characterized in that the sixth surface is formed at the end of the sixth surface is connected to the end of the seventh surface and the ninth surface inclined surface and the vertical surface. The method according to claim 1,
A predetermined interval between the yoke and the core is a solenoid valve for a transmission, characterized in that 1.5mm to 2.5mm. The method according to claim 1,
The valve unit has a hollow holder formed with one or more chambers and ports;
The at least one annular groove is formed and the solenoid valve for a transmission, characterized in that it comprises a spool vertically reciprocating in the holder by the solenoid portion. The method according to claim 5,
The holder is sequentially formed in the discharge chamber, the control chamber, the supply chamber and the feedback chamber in the direction of the solenoid portion,
The spool has a solenoid valve for a transmission, characterized in that the first annular groove and the second annular groove narrower than the first annular groove are sequentially formed in the direction of the solenoid portion. The method according to claim 5,
The holder is sequentially formed in the feedback chamber, the supply chamber, the control chamber and the discharge chamber in the direction of the solenoid portion,
The spool is a solenoid valve for a transmission, characterized in that the first annular groove and the second annular groove wider than the first annular groove in the direction of the solenoid portion is formed sequentially. The method according to claim 6 or 7,
A feedback flow path formed in the feedback chamber of the holder;
A supply port formed at one end of the supply chamber of the holder;
A control flow path formed in the control chamber of the holder;
A control port formed at one end of the control chamber of the holder, and
A solenoid valve for a transmission comprising a discharge port formed at one end of the discharge chamber of the holder. The method according to claim 8,
The feedback flow path is connected to the control flow path,
The feedback flow path is a solenoid valve for a transmission, characterized in that the diameter is 0.5mm to 1.5mm, the thickness is 1.5mm to 2.5mm. The method according to claim 8,
The solenoid valve for a transmission, characterized in that it further comprises a filter mounted to at least one of said supply port and said control port. The method according to claim 10,
At least one of the supply port and the control port is formed with a filter mounting groove,
The solenoid valve for a transmission, characterized in that the mounting jaw is formed on the end of the filter is mounted to the filter mounting groove, respectively. The method according to claim 1,
The solenoid valve for a transmission, characterized in that it further comprises a guide provided to surround the outer periphery of the core and the yoke to be integral with the core and the yoke. The method of claim 12,
Steps are formed on outer peripheries of the core and the yoke, respectively.
The guide is a solenoid valve for a transmission, characterized in that provided on the step.

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