JP4425761B2 - solenoid valve - Google Patents

Description

  The present invention relates to an electromagnetic valve that controls hydraulic pressure.

  2. Description of the Related Art Conventionally, an electromagnetic valve 101 as shown in FIG. 2 is used in a hydraulic path constituting an automatic transmission of an automobile.

  A solenoid 112 is accommodated in the casing 111 of the electromagnetic valve 101, and a core 113 is accommodated in the lower part of the solenoid 112. A plunger 114 is accommodated in the upper portion of the core 113, and the plunger 114 is configured to be attracted to the core 113 excited by the solenoid 112.

  A rod 121 extends downward from the plunger 114, and a small diameter portion 122 having a small diameter is formed at the tip of the rod 121. The small-diameter portion 122 is configured to penetrate the sheet member 124 provided in the nozzle 123, and a step portion formed at the base end of the small-diameter portion 122 opens to the upper surface of the sheet member 124. A discharge-side valve 126 that opens and closes the discharge-side opening 125 is configured.

  The input port 131 below the seat member 124 accommodates a ball valve 133 as an input side valve that opens and closes the input side opening 132 opened on the lower surface of the seat member 124, and the ball valve 133 is The rod 121 is configured to be urged downward by the small diameter portion 122. A drain port 134 is provided above the sheet member 124, and an output port 135 communicating with the outside is formed in the sheet member 124.

  Accordingly, when the solenoid 112 is not energized, the ball valve 133 is moved upward by receiving the original pressure from the input port 131 and the rod 121 is moved upward, so that the ball valve 133 is input to the seat member 124. While the side opening 132 is closed, the discharge side valve portion 126 is configured to open the discharge side opening 125, and the hydraulic pressure applied to the output port 135 is supplied to the output hole 136 and the discharge side opening. The drain port 134 can be discharged via the 125. Further, when the solenoid 112 is energized, the plunger 114 is attracted downward by the core 113, thereby biasing the ball valve 133 downward by the small diameter portion 122 of the rod 121, and the input side opening of the seat member 124. The hydraulic pressure from the input port 131 can be output from the output port 135 by closing the discharge side opening 125 by the discharge side valve portion 126 while opening 132.

  The solenoid valve 101 is configured to be supplied with an on / off signal to the solenoid 112, and configured to control the hydraulic pressure output from the output port 135 by duty-controlling the on / off signal. ing.

  However, in such a solenoid valve 101, when the solenoid 112 is not energized, the ball valve 133 closes the input-side opening 132 of the seat member 124, and the upper end of the rod 121 of the plunger 114 and the retaining valve A gap is formed between the stopper plate 141 and the stopper plate 141.

  Therefore, when the solenoid 112 is not energized, the plunger 114 has a state in which the upper end of the rod 121 is in contact with the stopper plate 141 and a state in which a gap is formed between the rod 121 and the stopper plate 141. And the distance from the plunger 114 to the core 113 changes each time. Then, the time from when the solenoid 112 is energized and the plunger 114 is sucked to when the input side opening 132 is opened is different each time, and the output pressure with respect to the duty ratio of the on / off signal applied to the solenoid 112 is different. There was a problem that changed.

  In order to prevent this, the structure which urges | biases a plunger with a coil spring is known (for example, refer patent document 1).

  By applying this technique, as shown in FIG. 3, a countersink hole 151 is provided at the end of the plunger 114, and a coil spring 152 is accommodated in the countersink hole 151 so that the plunger 114 is always attached downward. There are several ways to do this.

However, in this case, in order to prevent rattling of the plunger 114, it is necessary to increase the urging load by the coil spring 152, and the open / close failure due to the ball valve 133 operated by the hydraulic pressure from the input port 131 is likely to occur. was there. As a result, there is a concern about deterioration of output characteristics.
Japanese Patent No. 3442405

  The present invention has been made in view of such a conventional problem, and an object thereof is to provide an electromagnetic valve capable of further improving output characteristics.

In order to solve the above problems, in the solenoid valve of the present invention, the plunger is sucked by the core excited when the solenoid is energized, and the through-hole provided in the seat member by the discharge side valve provided in the shaft portion of the plunger when closing the discharge-side opening of the drain port side of the hole, before Symbol input side valve which has been closing the input side opening of the input port side of the through hole, with the shaft portion passing through the through hole The input side opening is moved to output the original pressure from the input port from the output port through the output hole communicating with the through hole. On the other hand, when the solenoid is not energized, the original pressure from the input port is output. The input side valve is closed by the input side valve that is retracted, and the plunger is moved away from the core via the shaft portion, and the discharge side valve provided on the shaft portion is moved. Move backwards A solenoid valve configured to open a side opening and discharge the pressure of the output port from the drain port, and to control the output pressure from the output port by duty-controlling an on / off signal applied to the solenoid; The input side valve is fixed to the shaft portion, and the input side valve that has received the original pressure is retracted and is in contact with the seat member, in a direction away from the core of the plunger provided in the shaft portion. The amount of movement to was regulated.

  That is, when the solenoid is de-energized, when the input side valve retracts due to the original pressure from the input port and closes the input side opening of the seat member, the shaft is moved along with the input side valve. The plunger is moved away from the core.

  At this time, the input side valve is fixed to the shaft portion, and the input side valve is in contact with the seat member in a direction away from the core of the plunger provided in the shaft portion. The amount of movement is regulated.

  For this reason, the input side valve and the shaft portion are configured to be independently movable, and when the solenoid is not energized, the distance from the plunger to the core changes each time as compared with the conventional case. The time from the opening to the input side opening is always kept constant.

  As described above, in the solenoid valve according to the present invention, the distance from the plunger to the core when the solenoid is not energized can be kept constant without using a biasing member that always biases the plunger. .

  For this reason, compared with the conventional case where the distance from the plunger to the core changes each time, the response time from energization of the solenoid to opening of the input side opening can be kept constant. Therefore, fluctuations in the output pressure with respect to the duty ratio of the on / off signal applied to the solenoid can be prevented, and the output characteristics can be further improved.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing an electromagnetic valve 1 according to the present embodiment, and the electromagnetic valve 1 controls the hydraulic pressure by a hydraulic circuit of an automatic transmission, for example.

  A bobbin 13 of a resin molded product 12 is accommodated in the casing 11 of the electromagnetic valve 1, and a coil 14 is wound around the bobbin 13 to form a solenoid 15. A core 16 is provided in the lower part of the inner space of the solenoid 15, and a plunger 17 sucked by the core 16 is accommodated in the upper part of the core 16 so as to be movable up and down.

  A folded portion 21 formed by folding the end portion of the casing 11 is fitted in the outer peripheral portion of the plunger 17, and the folded portion 21 constitutes a yoke. A closing lid 22 is provided on the end side of the folded portion 21, and the end of the solenoid 15 is closed by the closing lid 22.

  A cylindrical shaft portion 31 is provided at the center of the plunger 17, and the shaft portion 31 is fixed to the plunger 17 by a fixing member 32. The shaft portion 31 extending downward from the plunger 17 is inserted through a central hole 33 provided in the core 16 so as to be movable up and down, and a large-diameter hole 34 is provided below the central hole 33. A valve chamber 35 is formed. The valve chamber 35 communicates with a drain port 37 provided in the resin molded product 12 through a lateral hole 36.

  In the portion of the shaft portion 31 located in the valve chamber 35, a large-diameter portion larger in diameter than the general portion is provided, and a discharge side valve 41 is formed. A sheet member 42 is disposed below the discharge side valve 41, and the sheet member 42 is insert-molded into a nozzle 43 formed by the lower end portion of the resin molded product 12.

  The sheet member 42 is provided with a through hole 51 penetrating in the vertical direction and an output hole 52 penetrating in the horizontal direction, and the output hole 52 is configured to cross and communicate with the through hole 51. Has been. The output hole 52 communicates with an output port 53 formed in the nozzle 43 and is configured to output a controlled output pressure from the output port 53.

  The shaft portion 31 extending downward from the discharge side valve 41 passes through the through hole 51 in a loosely fitted state, and the upper portion of the through hole 51 is provided in the shaft portion 31. A discharge side opening 55 that is opened and closed by the discharge side valve 41 is configured.

  Further, the shaft portion 31 extending downward from the seat member 42 is provided with a small-diameter small-diameter portion 61, and a cylindrical input-side valve 62 is externally fitted to the small-diameter portion 61. It is press-fitted. A push nut 63 as a retaining member is fixed to the small diameter portion 61, and the input side valve 62 is sandwiched between the step portion 64 formed by the small diameter portion 61 and the push nut 63. It is fixed. The lower part of the through hole 51 constitutes an input side opening 66 communicating with an input port 65 formed in the nozzle 43, and the input side opening 66 is provided in the input portion provided in the shaft portion 31. The side valve 62 is configured to be opened and closed.

  The input side valve 62 is configured so that the plunger 17 fixed to the shaft portion 31 is in a state where the input side valve 62 is in contact with the opening edge of the input side opening 66 and closes the input side opening 66. It functions as a stopper that regulates the amount of movement in the direction away from the core 16.

  As a result, as shown on the right side in the figure, when the solenoid is energized 71, the plunger 17 is attracted by the core 16 excited by the solenoid 15, and the discharge side valve 41 provided on the shaft portion 31 of the plunger 17. The discharge side opening 55 of the seat member 42 is closed, and the input side valve 62 that has closed the input side opening 66 is moved downward to open the input side opening 66, and the input port The hydraulic pressure supplied from 65 can be outputted from the output port 53 through the output hole 52 communicating with the through hole 51.

  On the other hand, as shown on the left side in the figure, when the solenoid is not energized 75, the input side opening 66 is closed by the input side valve 62 that receives the hydraulic pressure from the input port 65 and retreats upward. The plunger 17 is moved in a direction away from the core 16 via the shaft portion 31, and the discharge side valve 41 provided on the shaft portion 31 is moved upward to open the discharge side opening portion 55. The pressure applied to the output port 53 can be discharged from the drain port 37.

  The coil 14 of the solenoid 15 of the solenoid valve 1 is configured to receive an on / off signal via a connection terminal 81. Duty control for varying the on time and off time of the on / off signal is performed. By doing so, the output pressure from the output port 53 can be controlled.

  In the present embodiment according to the above configuration, when the solenoid is not energized 75, the input side valve 62 is retracted upward by receiving the original pressure from the input port 65, and the input side opening 66 of the seat member 42 is retracted. When the valve is closed, the plunger 17 moves away from the core 16 through the shaft portion 31 that moves together with the input side valve 62.

  At this time, the input side valve 62 is fixed to the shaft portion 31, and the plunger 17 provided on the shaft portion 31 is in a state where the input side valve 62 is in contact with the seat member 42. The amount of movement in the direction away from the core 16 can be regulated.

  For this reason, the input side valve 62 and the shaft portion 31 are configured to be independently movable, and when the solenoid is not energized 75, the distance from the plunger 17 to the core 16 changes each time compared to the conventional case. Thus, the time from energization of the solenoid to the opening of the input side opening 66 can be kept constant.

  Thus, without using a biasing member that constantly biases the plunger 17, the distance from the plunger 17 to the core 16 when the solenoid is not energized 75 is kept constant, and from energizing the solenoid to opening the input side opening 66. The response time can be kept constant at all times, so that fluctuations in the output pressure with respect to the duty ratio of the on / off signal applied to the solenoid 15 can be prevented, and the output characteristics can be further improved.

It is sectional drawing which shows one embodiment of this invention. It is sectional drawing which shows the conventional solenoid valve. It is sectional drawing which shows another prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Solenoid valve 15 Solenoid 16 Core 17 Plunger 31 Shaft part 37 Drain port 41 Discharge side valve 42 Seat member 51 Through-hole 52 Output hole 53 Output port 55 Discharge side opening 62 Input side valve 65 Input port 66 Input side opening

Claims (1)

When the plunger is sucked by the core excited when the solenoid is energized, and the discharge side opening provided on the drain port side of the through hole provided in the seat member is closed by the discharge side valve provided on the shaft portion of the plunger , serial input-side valve which has been closing the input side opening of the input port side of the through hole, moving to open the input-side opening in the shaft portion passing through the through hole, from the input port While outputting the original pressure from the output port through the output hole communicating with the through hole,
When the solenoid is de-energized, the input side valve is closed by the input side valve that is retracted by receiving the original pressure from the input port, and the plunger is moved in a direction away from the core via the shaft, Retreating the discharge side valve provided in the shaft portion to open the discharge side opening, and configured to discharge the pressure of the output port from the drain port,
In an electromagnetic valve that controls an output pressure from the output port by duty-controlling an on / off signal applied to the solenoid,
The input side valve is fixed to the shaft portion, and the input side valve that has received the original pressure is moved backward and is in contact with the seat member, and is separated from the core of the plunger provided in the shaft portion. A solenoid valve characterized by restricting the amount of movement in the direction.

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