JP2003074732A - Solenoid valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solenoid valve that can downsize a solenoid part while preventing deformation when winding a coil even if thinning the wall thickness of a cylindrical part of a solenoid bobbin. SOLUTION: This solenoid valve is comprised of a valve part 2 accommodating a spool valve 9 in a valve housing 4, and the solenoid part 3 for displacing the spool valve 9 at one end of the valve housing 4. A thick-walled projecting part 19 fitted into a clearance 16 between a solenoid core 14 and an inner cylinder 15 formed on the base end side of a case 12 is formed on the inner periphery of the cylindrical part 18c of the solenoid bobbin 18 wound with a solenoid coil 17 of the solenoid part 3. The strength of the cylindrical part 18c is secured by the thick-walled projecting part 19 to thin the wall thickness of the cylindrical part 18c of the solenoid bobbin 18.

Description

Description: BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The present invention relates to a solenoid valve in which a valve is operated by a solenoid. 2. Description of the Related Art An automatic transmission or the like mounted on a vehicle is provided with a solenoid valve, which is supplied with hydraulic oil controlled to a predetermined pressure and driven. ing. Although not shown in FIG. 3, this type of solenoid valve is provided with a valve section in which a spool valve 9 is accommodated in a valve housing 4 having a supply pressure introduction port and a control pressure derivation port, And a solenoid unit 3 for displacing the spool valve 9. The solenoid portion 3 includes a hollow solenoid core 14 held on the valve housing 4 side and a hollow solenoid core 14 in a cylindrical case 12 connected to one end of the valve housing 4 by a caulking piece 13.
An inner cylinder 15 formed on the base end side of the case 12 on the same axis as the solenoid core 14 with a gap 16 between the end face on the opposite side to the valve housing 4 side.
And a cylindrical portion 18 of a solenoid bobbin 18 made of a non-magnetic material such as a synthetic resin having flanges 18a and 18b at both ends.
c, a coil is wound around the outer periphery of the case 12 and the solenoid coil 17 is inserted into the space between the solenoid core 14 and the inner cylinder 15, and the shaft 21 is inserted through a hollow portion of the solenoid core 14. Plunger 2 connected to spool valve 9 and moving on the same axis as solenoid core 14 by excitation of solenoid coil 17
0. Note that in FIG.
Is a disk spring supporting one end of the plunger 20, and 23 is a cap. The solenoid valve mounted on the automatic transmission or the like of the vehicle is disposed in a limited small space, so that the size (diameter) of the solenoid unit 3 can be reduced. Required. To reduce the size, the diameter of the solenoid coil 17 is reduced by reducing the thickness of the cylindrical portion 18c of the solenoid bobbin 18, and the diameter D2 of the cylindrical case 12 can be reduced. When the thickness of the cylindrical portion 18c of the bobbin 18 is reduced, when the coil is wound around the cylindrical portion 18c while applying tension to the coil,
As shown by the imaginary line in FIG.
8c is deformed in the radial direction, and cannot be inserted into the space between the case 12, the solenoid core 14, and the inner cylinder 15. Therefore, simply reducing the thickness of the cylindrical portion 18c of the solenoid bobbin 18 means that the solenoid portion 3
There was a problem that miniaturization (small diameter) could not be obtained. An object of the present invention is to provide an electromagnetic valve which prevents deformation during coil winding even if the thickness of a cylindrical portion of a solenoid bobbin is reduced, and allows the solenoid portion to be downsized. SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a valve section in which a spool valve is housed in a valve housing, and operates the valve section provided at one end of the valve housing. An electromagnetic valve comprising a solenoid part, wherein the solenoid part is a hollow solenoid core held on the valve housing side in a cylindrical case, and the valve housing side of the solenoid core is A coil is wound around the inner cylinder formed on the base end side of the case on the same axis as the solenoid core with a gap between the end face on the opposite side and the outer periphery of the cylindrical portion of the solenoid bobbin. A solenoid coil inserted into a space between the solenoid core and the inner cylinder, and being moved on the same axis as the solenoid core by excitation of the solenoid coil. And a plunger that operates to actuate the valve portion, forming a thick convex portion for reinforcing the cylindrical portion which is fitted into a gap between the solenoid core and the inner cylinder at an inner peripheral portion of the cylindrical portion of the solenoid bobbin. It is characterized by having done. Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1, reference numeral 1 denotes an electromagnetic valve according to the present invention, which comprises a valve portion 2 in which a spool valve 9 is accommodated in a valve housing 4 and a solenoid portion 3 provided at one end of the valve housing 4 to displace the spool valve 9. Have been. The valve section 2 has a supply pressure introducing port 5, a control pressure deriving port 6, a drain port 7 and a discharge port 8 in the valve housing 4. A spool valve 9 restricts the supply pressure introducing port 5. It has a land 9a for controlling and a land 9b for controlling the throttle of the drain port 7, and is slidably fitted to the valve housing 4. The spool valve 9 is attached to a shaft 21 which is axially moved by a plunger 20 of a solenoid unit 3 described later by a spring 11 interposed between a plug 10 screwed to the other end of the valve housing 4 and a tip of the spool valve 9. Spool valve 9
Is biased in a direction in which the rear end thereof abuts. The solenoid part 3 includes a hollow solenoid core 14 held on the valve housing 4 side and a hollow solenoid core 14 in a cylindrical case 12 connected to one end of the valve housing 4 by a caulking piece 13.
An inner cylinder 15 formed on the base end side of the case 12 on the same axis as the solenoid core 14 with a gap 16 between the end face on the opposite side to the valve housing 4 side.
And a cylindrical portion 18 of a solenoid bobbin 18 made of a non-magnetic material such as a synthetic resin having flanges 18a and 18b at both ends.
c, a coil is wound around the outer periphery of the case 12 and the solenoid coil 17 is inserted into the space between the solenoid core 14 and the inner cylinder 15, and the shaft 21 is inserted through a hollow portion of the solenoid core 14. Plunger 2 connected to spool valve 9 and moving on the same axis as solenoid core 14 by excitation of solenoid coil 17
0. Incidentally, in FIG.
Is a disk spring that supports one end of the plunger 20, 23 is a cap, 24 is a bearing bush of the shaft 21, and 25 and 26 are filters having a sealing function. When the control current applied to the solenoid coil 17 is zero, the plunger 20 is positioned at the leftmost rearward end in FIG. In this state, the space in front of the plunger 20 in the solenoid portion 3 is filled with oil for causing a damper function when the plunger 20 is suddenly sucked by applying a high control current to the solenoid coil 17. Accordingly, the present invention relates to the solenoid core 14
By forming a thick convex portion 19 for reinforcement of the cylindrical portion 18c fitted into the gap 16 at an inner peripheral portion of the cylindrical portion 18c of the solenoid bobbin 18 corresponding to the gap 16 between the cylinder bobbin 18 and the inner cylinder 15, The thickness t1 of the cylindrical portion 18c can be reduced. The operation of the embodiment of the present invention having the above configuration will be described. When the control current applied to the solenoid coil 17 is zero, the plunger 2
1 is located at the leftmost retreating end in FIG. 1 by a spring 11 that presses the spool valve 9, and the land portion 9 a of the spool valve 9 that throttles and controls the supply pressure introduction port 5 opens the supply pressure introduction port 5. Therefore, the fluid introduced from the supply pressure introduction port 5 is output from the control pressure derivation port 6 without controlling the pressure. When the plunger 20 is rapidly attracted by applying a high control current to the solenoid coil 17 from the above state, the oil sealed in the space in front of the plunger 20 in the solenoid portion 3 causes a damper action to be performed. Part 9a
Narrows the supply pressure introduction port 5 which is open, and
The b opens the drain port 7, reduces the supply pressure to a predetermined pressure, and outputs this from the control pressure derivation port 6 as a control pressure. When the current applied to the solenoid coil 17 is gradually increased from a low control current to a gradually high control current, the spool valve 9 strokes based on the applied current value, and the land 9a is opened to supply the supply pressure. The port 5 is squeezed in proportion to the applied current value, and the land portion 9b gradually opens the drain port 7, gradually reduces the supply pressure, and outputs the supply pressure from the control pressure derivation port 6 as the control pressure. At this time,
When the spool valve 9 starts to stroke, the land portion 9a,
9b, the supply pressure introduction port 5 and the control pressure derivation port 6 are both closed. In such a state, the longitudinal direction of each land 9a, 9b and the valve housing 4 (the direction in which the spool valve 9 moves) The control pressure supplied from the supply pressure introduction port 5 to the control pressure derivation port 6 and the drain port 7 is controlled by the respective wrap amounts in ()). The solenoid valve 1 according to the embodiment of the present invention, which performs the above-described operation, prevents deformation during winding of the coil even when the thickness t1 of the cylindrical portion 18c of the solenoid bobbin 18 is reduced. 3, the diameter D1 can be reduced, and the size can be reduced. That is, the solenoid core 14 and the case 1
2 and the inner cylinder 15 formed on the base end side of
6. By using the gap 16 to form a thick convex portion 19 fitted into the gap 16 on the inner periphery of the cylindrical portion 18c of the solenoid bobbin 18, the thickness of the cylindrical portion 18c of the solenoid bobbin 18 can be reduced. This is also because the thick convex portion 19 acts as a strength member of the cylindrical portion 18c and prevents deformation of the cylindrical portion 18c due to tension during coil winding. The thick protrusion 19 formed on the inner periphery of the cylindrical portion 18c of the solenoid bobbin 18
6, the solenoid core 14 and the case 1
The solenoid coil 17 can be correctly inserted into a fixed position in the space between the case 12 and the solenoid core 14 and the inner cylinder 15 without interfering with the inner cylinder 15 formed on the base end side of the second cylinder 2. Does not interfere with the plunger 20 and does not affect the movement of the plunger 20 at all. As described above, according to the present invention, the solenoid between the solenoid core and the inner cylinder formed on the base end side of the case is formed on the inner periphery of the cylindrical portion of the solenoid bobbin around which the coil is wound. By forming the thick protrusion fitted into the gap, even when the thickness of the cylindrical portion of the solenoid bobbin is reduced, the thick protrusion acts as a strength member of the cylindrical portion, and when the coil is wound. The tension prevents deformation of the cylindrical portion, and by reducing the thickness of the cylindrical portion, it is possible to reduce the size (diameter) of the solenoid portion. In addition, since the thick protrusion formed on the inner periphery of the cylindrical portion of the solenoid bobbin is fitted into the gap between the solenoid core and the inner cylinder formed on the base end side of the case, the solenoid coil is moved to a predetermined position. When it is assembled, it does not interfere with other parts, can be correctly assembled at a predetermined position, and does not affect the operation of the solenoid.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional view of a solenoid valve according to the present invention. FIG. 2 is a sectional view of a solenoid bobbin used in the solenoid valve according to the present invention. FIG. 4 is a sectional view of a solenoid bobbin used in a conventional solenoid valve [Description of symbols] 1 solenoid valve 2 valve section 3 solenoid section 4 valve housing 5 supply pressure introduction port 6 control pressure derivation port 7 drain port 9 Spool valve 9a Land part (of supply pressure introduction port) 9b Land part (of drain port) 12 Case 14 Solenoid core 15 Inner cylinder 16 formed in the case Gap between solenoid core and inner cylinder 17 Solenoid coil 18 Solenoid bobbin 18a Flange 18b Flange 18c Cylindrical part 19 Thick convex part 20 Plunger

Claims (1)

Claims: 1. An electromagnetic valve comprising: a valve section in which a spool valve is accommodated in a valve housing; and a solenoid section provided at one end of the valve housing to operate the valve section. The solenoid section has a gap in a cylindrical case between a hollow solenoid core held on the valve housing side and an end face of the solenoid core opposite to the valve housing side. An inner cylinder formed on the base end side of the case on the same axis as the solenoid core, and a coil is wound around the outer periphery of the cylindrical portion of the solenoid bobbin and inserted into the space between the case, the solenoid core and the inner cylinder. And a plunger that moves on the same axis as the solenoid core by actuation of the solenoid coil to operate the valve portion. , Solenoid valves, characterized in that the formation of the convex portion of the thick of the cylindrical portion for reinforcement to be fitted in the gap between the solenoid core and the inner tube to the inner peripheral portion of the cylindrical portion of the solenoid bobbin.