JP4011149B2 - solenoid valve - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electromagnetic valve used for a hydraulic circuit in an automatic transmission of an automobile, for example.
[0002]
[Prior art]
Conventionally, as this type of solenoid valve, for example, there is one shown in FIG. That is, the electromagnetic valve 51 includes a drive unit A in which the solenoid 2 is accommodated and a spool-like valve body 3 made of a magnetic material is slidably accommodated, and a nozzle 4 extending from the drive unit A. is doing. The nozzle 4 is fitted in a block (not shown) constituting a hydraulic circuit, and an inflow port 5 is formed inside the nozzle 4. A bobbin 6 is integrally formed with the nozzle 4 by a synthetic resin and wound with the solenoid 2 around the drive unit A, and a cylindrical guide member for holding the valve body 3 therein. 7 is fitted. A metal plate 8 is inserted between the bobbin 6 and the nozzle 4 so as to be exposed at the end face of the driving unit A from which the nozzle 4 extends. The metal plate 8 has an inflow port 10 communicating with the inflow port 5 and the outflow ports 9, 9 provided on the bottom side of the bobbin 6, and the metal plate 8 constitutes a valve seat. Further, the metal plate 8 is provided with a plurality of holes 11 around the inflow port 10, and the bobbin 6 and the nozzle 4 are connected through the holes 11. The periphery of the bobbin 6 and the base end portion of the nozzle 4 are covered with a metal cover 12 having a thickness of about 1 mm, and the step portion 13 of the cover 12 that is in contact with the metal plate 8 is indicated by an arrow in FIG. Thus, laser welding is performed on the metal plate 8 from the outside. Thus, the metal plate 8 forms a magnetic circuit together with the solenoid 2 through the cover 12. A plate-like yoke 14 that constitutes a magnetic circuit together with the metal plate 8 and the like, and a stopper plate 15 that determines the upper limit of movement of the valve body 3 are caulked and fixed by a cover 12 on the upper end side of the drive unit A. Yes.
[0003]
In such a solenoid valve, when the solenoid 2 is not excited, the valve body 3 moves in the direction of releasing the inlet 10 by the hydraulic pressure on the inflow port 5 side, while the solenoid 2 is excited. The hydraulic pressure on the inflow port 5 side is controlled by moving the inlet 10 in the closing direction. That is, it operates as a normally open type solenoid valve.
[0004]
[Problems to be solved by the invention]
However, in the conventional solenoid valve 51, when the metal plate 8 and the stepped portion 13 are laser-welded, it is necessary to ensure high adhesion between the two, but the cover 12 is pressed to reduce the cost. In general, it is difficult to ensure high flatness in the step portion 13 of the cover 12. For this reason, there are many cases where a slight gap is formed between the metal plate 8 and the step portion 13 during laser welding, and the amount of penetration L into the metal plate 8 side during the laser welding described above is not stable, As a result, there is a problem that it is difficult to ensure stable quality. Of course, such a situation can be avoided by separately processing the step portion 13 to ensure high flatness when the cover 12 is manufactured. However, this causes a new problem of high cost.
[0005]
This invention is made | formed in view of this conventional subject, and it aims at providing the solenoid valve which can stabilize the quality for every product, without causing high cost.
[0006]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, in the invention of claim 1, a drive part in which a solenoid is accommodated and a valve body is slidably accommodated, and a port extending from the drive part and communicating with the valve chamber A nozzle that forms a magnetic circuit together with the solenoid, and a cover that covers the drive unit and the base end of the nozzle. in step portion of the cover to interview the exposed surface of the extending direction of the nozzle before Symbol plate said plate and laser welded solenoid valve, the stepped portion of the cover, on the exposed surface of said plate It was assumed that a boss portion that protruded oppositely and was laser-welded to the plate was formed.
[0007]
In this configuration, the cover is welded to the plate via a boss formed on the stepped portion. Here, since the area of the boss part is smaller than the area of the step part, even when the step part is formed by deep drawing at the time of manufacturing the cover, when the boss part is brought into close contact with the plate during welding with the plate, the cover High adhesion can be ensured between the plate and the plate as compared with the case where the entire region of the step portion is in close contact with the plate.
[0008]
In the invention of claim 2, a plurality of the boss portions are provided on the stepped portion of the cover, and each of the boss portions is equally arranged in a circumferential direction centering on the nozzle. In such a configuration, since the entire area of the boss portion that contacts the plate during welding is further reduced, higher adhesion can be ensured between the cover and the plate when the boss portion is brought into close contact with the plate.
[0009]
In the invention of claim 3, the boss part is formed thinner than the other part of the cover. In such a configuration, even if the laser output used for welding is the same, the coupling region between the plate and the boss portion can be expanded.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view showing a normally open type electromagnetic valve 1 used in a hydraulic circuit of an automatic transmission in an automobile, similar to that shown in FIG. That is, the electromagnetic valve 1 includes a drive unit A in which a solenoid 2 is accommodated and a valve body 21 made of a magnetic material is slidably accommodated, and a nozzle 4 extending from the drive unit A. . In the following configuration, the same parts as those shown in FIG. 6 are denoted by the same reference numerals, description thereof will be omitted, and different parts will be described. The valve body 21 contacts and separates from the metal plate 8 and has a valve portion 22 at one end for opening and closing the inlet 10 opening to the metal plate 8, and an oil flow path inside the guide member 7 on its peripheral surface. A plurality of oil grooves 23 are provided. In the solenoid valve 1, the hole 15 a that opens in the stopper plate 15 serves as a discharge port. Therefore, when the solenoid 2 is not excited and the valve body 21 releases the inlet 10, The inflowing oil is discharged from the hole 15a to the outside through the oil groove 23.
[0011]
Further, as shown in FIG. 2, the stepped portion 13 of the cover 12 that is in contact with the exposed surface 8 a of the metal plate 8 on the extending direction side of the nozzle 4 has an annular shape that protrudes toward the metal plate 8 in a substantially hat shape. A boss portion 25 is formed. The thickness T1 of the boss portion 25 is set to about 0.7 mm, and the thickness T2 of the other general portions is set to about 1 mm as in the prior art (see FIG. 3). That is, the boss portion 25 is formed thinner than other general portions. And the metal plate 8 and the cover 12 are laser-welded from the outside using the boss | hub part 25 as shown by the arrow in FIG.
[0012]
In the electromagnetic valve 1 having the above configuration, the area of the boss portion 25 is smaller than the area of the entire step portion 13. For this reason, even if the step 13 is formed by deep drawing at the time of manufacturing the cover 12, when the boss 25 is brought into close contact with the metal plate 8 during welding, the gap between the cover 12 and the metal plate 8 is Compared to the conventional case where the entire region of the stepped portion 13 is brought into close contact with the metal plate 8, high adhesion can be ensured. Therefore, the amount of penetration L (see FIG. 3) into the metal plate 8 when performing laser welding can be stabilized more than before, and stable quality can be ensured in the solenoid valve 1 with less variation in coupling strength between the two. It becomes possible to do. At the same time, high adhesion can be secured, and as a result, the bonding strength between the cover 12 and the metal plate 8 can be improved.
[0013]
Moreover, in the present embodiment, since the boss portion 25 is formed thinner than the other portions of the cover 12 (step portion 13), even if the laser output used for welding is the same, The coupling region S (see FIG. 3) between the metal plate 8 and the boss portion 25 can be widened. Therefore, the coupling strength between the cover 12 and the metal plate 12 can be further improved without increasing the laser output.
[0014]
On the other hand, the boss portion 25 formed on the step portion 13 of the cover 12 is not necessarily formed in an annular shape as described above. For example, as shown in FIGS. 4 and 5, a plurality of boss portions 25. 4 may be equally arranged in the circumferential direction centered on 4. According to such a configuration, the entire area of the boss portions 25 that contact the metal plate 8 during welding is further reduced. Therefore, when the boss portions 25 are brought into close contact with the metal plate 8 , the cover 12 and the metal plate Higher adhesion can be ensured. Therefore, by further reducing the variation in the coupling strength between the two, more stable quality can be ensured in the solenoid valve 1. Further, in this case, as described above, if the boss portions 25... Are formed thinner than the other general portions of the cover 12, the boss portions 25. The area can be expanded. Accordingly, it is possible to prevent a reduction in the bonding strength between the cover 12 and the metal plate 8 due to a decrease in the overall area in contact with the metal plate 8 during welding.
[0015]
【The invention's effect】
As described above, in the first aspect of the present invention, the boss protruding toward the plate is formed on the step of the cover that is in contact with the plate exposed at the end face of the drive unit, and the step is deep when the cover is manufactured. Even if it has been formed by drawing, it is possible to ensure higher adhesion between the cover and the plate during welding. Therefore, the amount of penetration into the plate side when performing laser welding can be stabilized, and it is possible to ensure a stable quality in the electromagnetic valve with little variation in the bonding strength between the two. At the same time, high adhesion can be ensured, and as a result, the bond strength between the cover and the plate can be improved.
[0016]
In the invention of claim 2, a plurality of boss portions are provided on the step portion of the cover, and each boss portion is arranged uniformly in the circumferential direction centering on the nozzle, and the boss portions are in close contact with the plate. In some cases, higher adhesion can be secured between the cover and the plate. Therefore, by further reducing the variation in the coupling strength between the cover and the plate, it is possible to ensure more stable quality in the solenoid valve.
[0017]
Further, in the invention of claim 3, even if the boss part is formed thinner than the other part of the cover and the laser output used for welding is the same, the coupling between the plate and the boss part Made it possible to expand the area. Therefore, the coupling strength between the cover and the plate can be further improved without increasing the laser output.
[0018]
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an embodiment of the present invention.
FIG. 2 is a perspective view showing a bottom portion of the cover in a cut state.
FIG. 3 is an explanatory diagram corresponding to a part A in FIG. 1;
FIG. 4 is a plan view showing another cover.
FIG. 5 is a plan view showing another cover.
FIG. 6 is a cross-sectional view showing a conventional technique.
FIG. 7 is an explanatory diagram corresponding to part B in FIG. 6;
[Explanation of symbols]
1 Solenoid valve 2 Solenoid 4 Nozzle 5 Inflow port (port)
8 Metal plate (plate)
12 Cover 13 Step part 21 Valve body 25 Boss part A Drive part L Amount of penetration S (to metal plate) S Bonding area

Claims (3)

A drive unit in which a solenoid is accommodated and a valve body is slidably received, a nozzle that extends from the drive unit and forms a port that communicates with the valve chamber, and an end surface of the drive unit from which the nozzle extends while exposed to a plate constituting a magnetic circuit together with the solenoid, and a cover covering the drive portion and the base end of the nozzle, interviews on the exposed surface of the extending direction side of the nozzle before Symbol plate In the electromagnetic valve in which the step of the cover is laser welded to the plate,
Solenoid valve, characterized in that the stepped portion of the cover, a boss portion to which the are plate and laser welding with projecting toward the exposed surface of the plate is formed. The electromagnetic valve according to claim 1, wherein a plurality of the boss portions are provided on a step portion of the cover, and each of the boss portions is equally arranged in a circumferential direction centering on the nozzle. The electromagnetic valve according to claim 1 or 2, wherein the boss portion is formed thinner than the other part of the cover.

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