JPH08203730A - Solenoid - Google Patents

Abstract

PURPOSE: To make it possible to prevent an air current from being leaked when the air is fed to a fixed iron core by installing a clamped member to the fixed iron core where the clamped member is clamped between a clamping part installed to a coil frame by pressing the coil frame with a coupling force which forces a yoke to be coupled with a frame and a bottom plate. CONSTITUTION: A corner part on both sides of a notched part 6d is caulked with a tool, such as a caulking punch. A yoke 7 and a stopper 8 are coupled with a frame 6. Since a coupling force produced with the tool is directed at a bottom 6a of the frame 6, this coupling force pushes a coil frame 1 at the bottom plate 6a of the frame 6. The fixed iron core 3 is fixed with the bottom plate 6a of the frame 6 by clamping the clamped part 3b between the clamping part 1f of the coil frame 1 and the bottom plate 6a of the frame 6. At that time, a clearance S is installed to the coil frame 1 between the bottom plate 6a so as to keep off contact with the bottom plate 6a of the frame 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solenoid having a tubular fixed iron core and used for an electromagnetic valve such as a blood pressure monitor.

[0002]

2. Description of the Related Art As a first conventional example of this type of solenoid, there is one having a structure shown in FIGS. This is a cylindrical coil frame A in which a collar portion A ₃ is provided at both ends of a winding drum portion A ₂ having an axial hole A ₁ , and a coil B wound around the winding drum portion A ₂ of the coil frame A. And a frame C that has a bottom plate C ₂ with a through hole C ₁ and has a substantially U-shaped cross section that surrounds the coil B, and a through hole C ₁ of the frame C that is inserted through the frame C and is near the outer surface of the frame C. Coil frame A that is crimped and fixed and has one end opening D ₁
The tubular fixed core D formed so that the shaft hole A ₁ of the other end and the opening D _{2 of the} other end communicate with each other, and the yoke E connected to the frame C.
A movable iron core F that moves toward the fixed iron core D on the coil center axis so as to form a closed magnetic circuit via the frame C and the yoke E, and a return spring G that urges the movable iron core F in the return direction. , A stopper H for limiting the movement of the movable iron core F urged by the return spring G.

Next, the operation of this device will be described with reference to FIG. When coil B is not excited,
As shown in (a), the movable iron core F is urged by the return spring G and the movement of the movable iron core F is restricted by the stopper H, and one end of the fixed iron core D located in the shaft hole A ₁ of the coil frame A is moved. Since it faces the opening D ₁ with a facing distance, the one end opening D ₁ of the fixed iron core D ₁ is open. Therefore, the airflow sent from the other end opening D ₂ of the fixed iron core D passes through the one end opening D ₁ and a small gap between the inner edge of the axial hole A ₁ of the coil frame A and the movable iron core F. Is ready to pass.

Then, when the coil is excited, FIG.
As shown in, the movable iron core F is moved toward the fixed iron core D so as to form a closed magnetic circuit, and one end of the fixed iron core D is opened.
When D ₁ is closed, the airflow cannot pass through the slight gap between the inner edge of the axial hole A ₁ of the coil frame A and the movable iron core F.

As a second conventional example of this type of solenoid, there is one having a structure shown in FIG. This one is
A cylindrical coil frame A having flanges A _{3 at} both ends of a winding barrel A ₂ having an axial hole A ₁ , a coil B wound around the winding barrel A ₂ of the coil frame A, and a through hole. Coil B with bottom plate C ₂ provided with C ₁
The frame C, which has an approximately U-shaped cross section, and the screw hole C ₁ that penetrates the frame are fixed by screws and fixed at one end.
A tubular fixed core D formed so that the axial hole A ₁ of the coil frame A where D ₁ is located and the other end opening D ₂ communicate with each other, and the frame C
Fixed to the center axis of the coil so that a closed magnetic circuit is formed through the yoke E coupled to the frame C and the yoke E.
The movable iron core F that moves toward the direction, the return spring G that urges the movable iron core F in the return direction, and the stopper that limits the movement of the movable iron core F urged by the return spring G.
With H and. And this is the first
It operates similarly to the embodiment.

[0006]

In the solenoid of the first conventional example described above, the fixed iron core D is fixed to the frame C by a relatively easy process such as caulking, so that no assembly work is required. .

However, as shown in FIG.
Outer diameter L of the part of the heart D inside the frame C ₁And outside frame C
Outer diameter L of the part₂When the difference between and is small, caulking width L₃Is small
It will get worse. For example, outer diameter L₁Is 4 mm
Outer diameter L₂Is 3 mm, the through hole C of the frame C₁Opening
Dimension L between the end and the inner part of frame C of fixed core D
_FourEven if 0.2mm, crimping width L₃Is 0.3 mm
Only 0.3mm of caulking width L₃Ok
Therefore, it will have to be processed. Then, caulking
The inner diameter of the caulking punch, which is a tool used for
Outer diameter L of D₂It is very close to
If there is eccentricity, the fixed iron core D will be damaged and
The air flow sent to the fixed core D from the scratch may leak.
It

Further, in the solenoid of the second conventional example described above, since it is fixed to the frame C by being screwed, as in the first conventional example, the fixed iron core D is damaged when caulking. Not attached.

However, it is necessary to cut a thread groove in the through hole C ₁ of the frame C and the fixed iron core D, and further, after fixing the screw, apply a lock nut or an adhesive material to prevent the rotation of the screw. Takes time and effort.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a solenoid which does not require assembly work and which does not leak an air flow when air is fed to a fixed iron core. Especially.

[0011]

In order to solve the above-mentioned problems, according to a first aspect of the present invention, there is provided a tubular coil frame in which a collar portion is provided at both ends of a winding drum portion having an axial hole, A coil wound around the winding body of the coil frame, a frame having a bottom plate provided with a through hole and having a substantially U-shaped cross section that surrounds the coil, and a fixed end inserted through the through hole of the frame. A tubular fixed iron core formed so that the axial hole of the coil frame in which is located and the other end opening communicate with each other, and a yoke coupled to the frame,
A movable iron core that moves toward a fixed iron core on the coil central axis so as to form a closed magnetic circuit via the frame and the yoke;
In a solenoid having a return spring for urging the movable iron core in the return direction and a stopper for limiting the movement of the movable iron core urged by the return spring, the yoke is connected to the frame by a connecting force. When the coil frame is pressed, a sandwiched portion that is sandwiched between the sandwiched portion provided on the coil frame and the bottom plate is provided on the fixed iron core.

According to a second aspect of the present invention, in the first aspect, the sandwiching portion is provided on the collar portion.

According to a third aspect of the present invention, in the first aspect, a gap is provided between the coil frame and the bottom plate.

[0014]

According to the first aspect of the present invention, in the fixed iron core, the clamped portion of the coil frame is clamped between the clamped portion and the bottom plate when the coil frame is pressed by the coupling force with which the yoke is coupled to the frame. It is sandwiched between and fixed to the bottom plate of the frame.

According to the second aspect of the present invention, since the collar portion has a larger diameter than the winding drum portion, the holding portion having a larger diameter is provided than when the holding portion is provided on the winding drum portion. Therefore, the diameter of the sandwiched portion provided on the fixed iron core can also be increased.

According to the third aspect of the present invention, since the coil frame is provided with a gap between the coil frame and the bottom plate even when it is pressed by the coupling force that is coupled to the frame of the yoke, the coil frame is being pressed. Since there is no restriction on the contact with the bottom plate and the pressing, the pressing can be performed sufficiently.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIG. This solenoid has coil frame 1, coil 2,
Fixed iron core 3, O-ring 4, movable iron core 5, frame 6,
It is composed of a yoke 7, a stopper 8 and a return spring 9.

The coil frame 1 is formed of a molding material such as plastic into a tubular shape having one and the other flange portions 1c and 1d at both ends of a winding drum portion 1b having a shaft hole 1a. Coil 2 is wound around. Further, the one-side flange portion 1c has a small diameter portion 1e formed by cutting out an end portion.

The fixed iron core 3 is made of a magnetic material and is made of a hollow material 3a.
It is formed in a tubular shape having, and has a thick axis slightly closer to one end than the center. The thick shaft portion is a sandwiching portion having a convex cross-section that is protruded from the winding drum portion 1b toward the axial center of the shaft hole 1a.
The 1f serves as a clamped portion 3b that is clamped during assembly. The hollow part 3a of the fixed core 3 has an opening at one end.
A small diameter portion 3d is formed slightly closer to the center than 3c, and an arrangement portion 3e in which the O-ring 4 is arranged is formed between the small diameter portion 3d and the one end opening portion 3c. And this fixed iron core 3
When it is inserted into the through hole 6c of the bottom plate 6a of the frame 6, a pipe portion 3g is formed between the other end opening 3f and the insertion portion to which a hose (not shown) or the like is piped.

The movable iron core 5 is formed of a magnetic material in a substantially round bar shape, and one end portion in the axial direction serves as a thin shaft to form a step portion 5a.

The frame 6 is made of a magnetic material and has a bottom plate 6a and opposing plates 6b, 6b and is formed in a U shape. A through hole 6c is formed in the center of the bottom plate 6a, and both opposing plates 6
Notches 6d and 6d, which are slightly wider than the width of the yoke 7, are provided at the centers of the tips of b and 6b, respectively, as shown in FIG.

The yoke 7 is formed of a magnetic material in a substantially square plate shape, and a through hole 7a is formed in the center thereof. As will be described later in detail, the yoke 7 is joined to the frame 6 by caulking together with the stopper 8.

The stopper 8 includes a central piece 8a and both facing pieces 8a.
Extending pieces 8c having a width approximately equal to the width of the yoke 7 are formed in a U-shape by b and 8b, and in the direction away from each other from the center of the tips of the facing pieces 8b and 8b.

The return spring 9 is formed by winding a spring wire in a cylindrical shape, and both ends of the return spring 9 are in pressure contact between the holding portion 1f of the coil frame 1 and the step portion 5a of the movable iron core 5, It is arranged in the shaft hole 1a of the coil frame 1.

Next, a procedure for fixing the fixed iron core 3 to the frame 1 will be described. First, the opening 3c at one end is the frame 6
The fixed iron core 3 is inserted into the through hole 6c such that the other end opening 3f is located inside the frame 6 and outside the frame 6. And
The coil frame 1 in which the coil 2 is wound around the winding barrel 1b is arranged in advance so that the sandwiched portion 3b of the fixed iron core 3 is located between the sandwiching portion 1f and the bottom plate 6a of the frame 6. At this time, the fixed iron core 3
The one end opening 3c is located in the shaft hole 1a of the coil frame 1. Then, the yoke 7 is bridged between the notches 6d, 6d of the frame 6 so that the movable iron core 5 is inserted into the through hole 7a. At this time, the yoke 7 is in contact with the one end flange portion 1d and the small diameter portion 1e of the coil frame 1, respectively. Then stopper
Similarly to the yoke 7, the bridge 8 is bridged between the notches 6d and 6d of the frame 6, and in this state, the yoke 7 and the stopper 8 are coupled to the frame 6. That is, the notch shown in FIG. 2 (a)
When the corners of both sides of 6d are swaged with a tool (not shown) such as a caulking punch, the yoke 7 and the stopper 8 are joined to the frame 6 as shown in FIG. At this time,
Since the coupling force f by the tool is directed to the bottom plate 6a of the frame 6, the coil frame 1 is also coupled to the frame 6 by this coupling force f.
Will be pressed toward the bottom plate 6a of the
Is clamped between the clamping portion 1f of the coil frame 1 and the bottom plate 6a of the frame 6, so that the fixed iron core 3 is fixed to the bottom plate of the frame 6.
It is fixed to 6a. At this time, the coil frame 1 is
Since it does not come into contact with the bottom plate 6a, a space S is provided between it and the bottom plate 6a.

Next, the operation of this device will be described with reference to FIG. When coil 2 is not excited,
As shown in (a), the movable iron core 5 is biased by the return spring 9 so that the movement of the movable iron core 5 is restricted by the stopper 8, and one end of the fixed iron core 3 located in the shaft hole 1a of the coil frame 1 is opened. Since it faces the portion 3c with a facing distance, the one end opening 3c of the fixed iron core 3 is in an open state. Therefore, the air flow sent from the other end opening 3f of the fixed iron core 3 can pass through the one end opening 3c and pass through a slight gap between the inner edge of the shaft hole 1a of the coil frame 1 and the movable iron core 5. It is in a state.

Then, when the coil is excited, FIG.
As shown in, the movable iron core 5 is moved toward the fixed iron core 3 so as to form a closed magnetic path, and one end of the fixed iron core 3 is opened.
3c is closed so that the airflow cannot pass through a slight gap between the inner edge of the shaft hole 1a of the coil frame 1 and the movable iron core 5.

In such a solenoid, the fixed iron core 3
The yoke 7 is coupled to the frame 6 by pressing the coil frame 1 with a coupling force f, so that the clamped portion 3b moves to the bottom plate 6a.
It is clamped by the clamping part 1f of the coil frame 1 between
Since it is fixed to the bottom plate 6a of 6, it does not require assembling as in the second embodiment in which it is screwed, and it does not need to be caulked near the fixed iron core 3 as in the first embodiment. As it is not damaged, the air flow will not leak when air is sent to the fixed iron core 3.

In the coil frame 1, the yoke 7 is the frame.
Since there is a space S between the bottom plate 6a and the bottom plate 6a even if the bottom plate 6a is pressed by the connecting force f that is coupled to the base plate 8, there is a limit to the contact with the bottom plate 6a during the pressing. Since it is not pressed, the holding portion 1f firmly holds the held portion 3b of the fixed iron core 3 and the fixed iron core 3 can be fixed in a stable state.

Further, the fixed iron core 3 is provided with a piping portion 3g and a frame 6
Since it is not directly fixed to the bottom plate 6a by caulking or the like, even if the diameter of the piping portion 3g is changed within a range where it can be inserted into the through hole 6c, it is not necessary to change the diameter of the through hole 6c. Each component such as the frame 6 can be shared with the fixed iron core 3 having the pipe portion 3g.

Next, a second embodiment of the present invention will be described below with reference to FIG. The members having substantially the same functions as those in the first embodiment are designated by the same reference numerals, and only the differences from the first embodiment will be described.

In the first embodiment, the holding portion 1f is provided on the winding drum portion 1b, whereas in the present embodiment, the holding portion 1f is provided on the other flange portion 1d. Specifically, the opening edge near the other flange 1d is cut out so that the opening of the shaft hole 1a has a large diameter, and the cutout portion serves as the holding portion 1f.

In such a solenoid, in addition to the effect of the first embodiment, since the diameter of the other flange portion 1d is larger than that of the winding drum portion 1b, the holding portion 1f is provided in the winding drum portion 1b. Since the sandwiching portion 1f having a larger diameter than that in the first embodiment can be provided, the sandwiched portion 3b provided in the fixed iron core 3 can also have a large diameter, so that the frame 6 of the fixed iron core 3 can be provided.
The area of the contact portion with and becomes larger, the magnetic resistance becomes smaller, and the magnetic characteristics become more stable.

In the first and second embodiments, the air gap S is provided between the coil frame and the bottom plate, but the fixed iron core 3
Is pressed firmly against the bottom plate 6a of the frame 6,
The space S may not be provided, and in that case, the degree of freedom in design is increased.

[0035]

According to the first aspect of the present invention, in the fixed iron core, the clamped portion of the coil frame is clamped between the clamped portion and the bottom plate by pressing the coil frame by the coupling force with which the yoke is coupled to the frame. Since it is sandwiched between and fixed to the bottom plate of the frame, it does not require assembling as in the second embodiment in which the screws are screwed, and the caulking process is performed near the fixed iron core as in the first embodiment. Since it does not happen, it will not be damaged and the air flow will not leak when air is sent to the fixed iron core.

According to the second aspect, in addition to the effect of the first aspect, since the diameter of the collar portion is larger than that of the winding drum portion, the collar portion is provided with a holding portion, Since the sandwiching portion having a larger diameter can be provided, the diameter of the sandwiched portion provided on the fixed iron core can also be increased, so that the area of the abutting portion of the fixed iron core with the frame is increased and the magnetic resistance is reduced. It becomes smaller and the magnetic characteristics become more stable.

According to a third aspect of the present invention, in addition to the effect of the first aspect, a gap is provided between the coil frame and the bottom plate even if the coil frame is pressed by the coupling force coupled to the frame of the yoke. Since there is no restriction on the contact with the bottom plate to be pressed while being pressed, it is pressed sufficiently, so that the holding part firmly holds the held part of the fixed iron core. , The fixed iron core can be fixed in a stable state.

[Brief description of drawings]

FIG. 1 is a sectional view of a first embodiment of the present invention.

FIG. 2 is a partial front view showing a state in which the above yoke is caulked and coupled to a frame.

FIG. 3 is a sectional view of a second embodiment of the present invention.

FIG. 4 is a cross-sectional view of a first conventional example.

FIG. 5 is a cross-sectional view showing a state in which the above fixed iron core is fixed to a frame.

FIG. 6 is a sectional view of a second conventional example.

[Explanation of symbols]

 1 Coil frame 1a Shaft hole 1b Winding barrel 1d Other flange 1f Clamping part 2 Coil 3 Fixed iron core 3c One end opening 3b Clamped part 3f Other end opening 5 Movable iron core 6 Frame 6c Through hole 6a Bottom plate 7 Yoke 8 Stopper 8 9 Return spring 9 S Air gap f Coupling force

Claims (3)

[Claims] 1. A tubular coil frame having flanges at both ends of a winding drum portion having an axial hole, a coil wound around the winding drum portion of the coil frame, and a bottom plate having a through hole. A frame having a substantially U-shaped cross section which surrounds the coil, and a shaft hole of the coil frame which is fixed by being inserted into a through hole of the frame and has an opening at one end and an opening at the other end are formed to communicate with each other. A tubular fixed iron core, a yoke connected to the frame, a movable iron core that moves toward the fixed iron core on the coil center axis so as to form a closed magnetic circuit through the frame and the yoke, and the movable iron core in the return direction. A solenoid provided with a return spring for urging and a stopper for restricting movement of a movable iron core urged by the return spring, wherein the coil frame is pressed by a coupling force with which the yoke is coupled to the frame. By the carp Solenoids, characterized in that the clamped portion sandwiched state between the clamping portion provided in the frame and the bottom plate is provided in the fixed iron core. 2. The solenoid according to claim 1, wherein the sandwiching portion is provided on the collar portion. 3. The solenoid according to claim 1, wherein a gap is provided between the coil frame and the bottom plate.